Electrical current measurement and rapidly locating and positively identifying cathodes having abnormal electrical conditions associated therewith in an electrolytic copper refining process tankhouse

Claim 2

Apparatus for measuring electrical current passing through at least one conductor which comprises at least one electrical current measuring instrument, the measuring instrument comprising: a. supporting means; b. a normally open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, pivotally mounted, automatically closeable and automatically openable jaws at least when the instrument is in a generally vertical orientation with the jaws below the supporting means, the jaws when closed substantially encompassing the conductor for the current measuring; c. means moveable on the supporting means of (a) and supporting the normally open sensing head jaws; d. means pivotally mounting the jaws on the last-mentioned moveable supporting means; e. means connecting outer end portions of the pivoted jaw mounting means with the supporting means; f. means maintaining the jaws in an open position when contacting means hereafter specified is not forcefully applied against a solid surface; and g. contacting means attached to the last-mentioned moveable supporting means, forceful application of the contacting means against a solid surface effecting movement of the moveable supporting means in a direction resulting in the closing of the jaws to substantially encompass the conductor and withdrawal of the forceful application of the contacting means from against the solid surface resulting in movement of the moveable supporting means in a different direction to effect the opening of the jaws at least when the instrument is in a generally vertical orientation with the jaws below the supporting means; h. the sensing head adapted to be operatively associated with means for measuring the electrical current passing through the conductor.

Claim 3

An instrument for measuring electrical current passing through a conductor, which comprises: a. supporting means; b. a normally open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, pivotally mounted, automatically closeable and automatically openable jaws at least when the instrument is in a generally vertical orientation with the jaws below the supporting means, the jaws when closed substantially encompassing the conductor for the current measuring; c. means moveable on the supporting means of (a) and supporting the normally open sensing head jaws; d. means pivotally mounting the jaws on the last-mentioned moveable supporting means; e. means connecting outer end portions of the pivoted jaw mounting means with the supporting means; f. means maintaining the jaws in an open position when contacting means hereafter specified is not forcefully applied against a solid surface; and g. contacting means attached to the last-mentioned moveable supporting means, forceful application of the contacting means against a solid surface effecting movement of the moveable supporting means in a direction to result in the automatic closing of the jaws to substantially encompass the conductor and withdrawal of forceful application of the contacting means from against the solid surface resulting in movement of the moveable supporting means in a different direction to effect the automatic opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means; h. the sensing head adapted to be operatively associated with means for measuring the electrical current passing through the conductor.

Claim 4

An instrument for measuring electrical current passing through a conductor, which comprises: a. supporting means; b. a normally open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, pivotally mounted, automatically closeable and automatically openable jaws at least when the instrument is in a generally vertical orientation with the jaws below the supporting means, the jaws when closed substantially encompassing the conductor for the current measuring; c. means moveable on the supporting means of (a) and supporting the normally open sensing head jaws; d. means pivotally mounting the jaws on the last-mentioned moveable supporting means; e. means connecting outer end portions of the pivoted jaw mounting means with the supporting means; f. means maintaining the jaws in an open position when contacting means hereafter specified is not forcefully applied against a solid surface; and g. contacting means attached to the last-mentioned moveable supporting means, forceful application of the contacting means against a solid surface effecting movement of the moveable supporting means in a direction to result in the automatic closing of the jaws to substantially encompass the conductor and withdrawal of forceful application of the contacting means from against the solid surface resulting in movement of the moveable supporting means in a different direction to effect the automatic opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means; h. the sensing head adapted to be operatively associated with means for measuring the electrical current passing through the conductor.

Claim 5

An instrument for measuring direct electrical current passing through a conductor, which comprises: a. supporting means; b. a normaLly open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, automatically closeable and automatically openable jaws when the instrument is in a generally vertical position with the jaws below the supporting means, the jaws when closed substantially encompassing the conductor for the current measuring; c. moveable yoke means including an inverted generally U-shaped yoke member moveable on the supporting means and supporting the normally open sensing head jaws; d. hinge means including a substantially centrally disposed, with reference to a upper portion of the hinge means, pivot pin hingedly mounting the jaws on the movable yoke means yoke member; e. link means pivotally interconnecting and linking outer end portions of the hinge means with a lower portion of the supporting means; f. means maintaining the jaws in an open position when contacting means hereafter specified is not forcefully applied against the conductor; and g. contacting means of a substantially non-electrically conductive material attached to a lower portion of the yoke means yoke member and extending beyond the yoke member end, forceful application of the contacting means against the conductor effecting movement of the yoke member in a direction to result in closing of the jaws to substantially encompass the conductor, and withdrawal of forceful application of the contacting means from against the conductor resulting in movement of the moveable yoke member in an opposite direction when the instrument is in a generally vertical orientation with the jaws below the supporting means, to effect opening of the jaws; h. the sensing head adapted to be operatively associated with means for measuring the electrical current passing through the conductor.

Claim 6

An instrument for measuring direct electrical current passing through a conductor, which comprises: a. supporting means; b. a normaLly open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, automatically closeable and automatically openable jaws when the instrument is in a generally vertical position with the jaws below the supporting means, the jaws when closed substantially encompassing the conductor for the current measuring; c. moveable yoke means including an inverted generally U-shaped yoke member moveable on the supporting means and supporting the normally open sensing head jaws; d. hinge means including a substantially centrally disposed, with reference to a upper portion of the hinge means, pivot pin hingedly mounting the jaws on the movable yoke means yoke member; e. link means pivotally interconnecting and linking outer end portions of the hinge means with a lower portion of the supporting means; f. means maintaining the jaws in an open position when contacting means hereafter specified is not forcefully applied against the conductor; and g. contacting means of a substantially non-electrically conductive material attached to a lower portion of the yoke means yoke member and extending beyond the yoke member end, forceful application of the contacting means against the conductor effecting movement of the yoke member in a direction to result in closing of the jaws to substantially encompass the conductor, and withdrawal of forceful application of the contacting means from against the conductor resulting in movement of the moveable yoke member in an opposite direction when the instrument is in a generally vertical orientation with the jaws below the supporting means, to effect opening of the jaws; h. the sensing head adapted to be operatively associated with means for measuring the electrical current passing through the conductor.

Claim 7

An instrument for measuring direct electrical current passing through a bar conductor, which comprises: a. an elongate handle; b. a normally open tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle, the jaws when closed substantially encompassing the conductor for the current measuring; c. a moveable yoke assembly including an inverted generally U-shaped yoke member moveable on the handle and supporting the normally open sensing head jaws; d. hinge means hingedly mounting the jaws on the inverted generally U-shaped yoke member, said hinge means including hinge plates secured to upper portions of the jaws by a substantially centrally disposed, with reference to the hinge means, pivot pin extending through the passageways of axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member; e. link means pivotally interconnecting and linking outer end portions of the hinge means hinge plates with a lower portion of the handle; f. the weight of instrument parts including the sensing head jaws and the moveable yoke assembly maintaining the jaws in an open position when shoes hereafter specified are not forcefully applied against the conductor; g. means limiting the extent of opening of the jaws but allowing them to open sufficiently wide to enable said jaws to be positioned about the conductor; and h. shoes of a substantially non-electrically conductive material attached to a lower portion of the inverted generally U-shaped yoke member and extending beyond the yoke member end, forceful application of the shoes against the conductor effecting movement of the moveable yoke assembly in a direction to produce moments of force aBout the centrally disposed pivot pin thereby resulting in closing of the jaws to substantially encompass the conductor and withdrawal of the forceful application of the shoes from against the conductor resulting in movement of the moveable yoke assembly in an opposite direction thereby resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; i. the sensing head adapted to be operatively as-sociated with means for measuring the electrical current passing through the conductor.

Claim 8

An instrument for measuring direct electrical current passing through a bar conductor, which comprises: a. an elongate handle; b. a normally open tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle, the jaws when closed substantially encompassing the conductor for the current measuring; c. a moveable yoke assembly including an inverted generally U-shaped yoke member moveable on the handle and supporting the normally open sensing head jaws; d. hinge means hingedly mounting the jaws on the inverted generally U-shaped yoke member, said hinge means including hinge plates secured to upper portions of the jaws by a substantially centrally disposed, with reference to the hinge means, pivot pin extending through the passageways of axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member; e. link means pivotally interconnecting and linking outer end portions of the hinge means hinge plates with a lower portion of the handle; f. the weight of instrument parts including the sensing head jaws and the moveable yoke assembly maintaining the jaws in an open position when shoes hereafter specified are not forcefully applied against the conductor; g. means limiting the extent of opening of the jaws but allowing them to open sufficiently wide to enable said jaws to be positioned about the conductor; and h. shoes of a substantially non-electrically conductive material attached to a lower portion of the inverted generally U-shaped yoke member and extending beyond the yoke member end, forceful application of the shoes against the conductor effecting movement of the moveable yoke assembly in a direction to produce moments of force aBout the centrally disposed pivot pin thereby resulting in closing of the jaws to substantially encompass the conductor and withdrawal of the forceful application of the shoes from against the conductor resulting in movement of the moveable yoke assembly in an opposite direction thereby resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; i. the sensing head adapted to be operatively as-sociated with means for measuring the electrical current passing through the conductor.

Claim 9

An instrument for measuring direct electrical current passing throug a bar conductor, which comprises: a. an elongate handle; b. a normally open, tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle, the jaws having generally arcuate inner surfaces, said jaws when closed substantially encompassing the conductor for the current measuring; c. moveable yoke means including an inverted generally U-shaped yoke member moveable on the handle and supporting the normally open tong-like jaws; d. hinge means hingedly mounting the jaws on the moveable yoke means yoke member, said hinge means including hinge plates secured to upper portions of the jaws, and a substantially centrally disposed, with reference to the hinge means, pivot pin extending through axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member; e. links pivotally connected to and linking outer end portions of the hinge means hinge plates with outer end portions of a crossbar affixed in a slot in a lower portion of the handle; f. the crossbar affixed in the slot in the lower portion of the handle; g. the weight of instrument parts including the sensing head jaws and the moveable yoke means maintaining the tong-like jaws in an open position when shoes hereinafter specified are not forcefully applied against the conductor; h. means limiting the extent of opening of the jaws but allowing them to open sufficiently wide to enable said jaws to be positioned about the conductor; and i. shoes of a substantially non-electrically conductive material attached to a lower portion of the inverted generally U-shaped yoke member and extending beyond the yoke member end, forceful application of the shoes against the conductor effecting movement of the yoke member in a direction to produce moments of force about the centrally disposed hinge pin thereby resulting in closing of the jaws to substantially encompass the conductor, and withdrawal of forceful application of the shoes from against the conductor resulting in movement of the yoke member in an opposite direction due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; j. the sensing head adapted to be operatively associated with means for measuring the direct current passing through the conductor.

Claim 10

An instrument for measuring direct electrical current passing throug a bar conductor, which comprises: a. an elongate handle; b. a normally open, tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle, the jaws having generally arcuate inner surfaces, said jaws when closed substantially encompassing the conductor for the current measuring; c. moveable yoke means including an inverted generally U-shaped yoke member moveable on the handle and supporting the normally open tong-like jaws; d. hinge means hingedly mounting the jaws on the moveable yoke means yoke member, said hinge means including hinge plates secured to upper portions of the jaws, and a substantially centrally disposed, with reference to the hinge means, pivot pin extending through axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member; e. links pivotally connected to and linking outer end portions of the hinge means hinge plates with outer end portions of a crossbar affixed in a slot in a lower portion of the handle; f. the crossbar affixed in the slot in the lower portion of the handle; g. the weight of instrument parts including the sensing head jaws and the moveable yoke means maintaining the tong-like jaws in an open position when shoes hereinafter specified are not forcefully applied against the conductor; h. means limiting the extent of opening of the jaws but allowing them to open sufficiently wide to enable said jaws to be positioned about the conductor; and i. shoes of a substantially non-electrically conductive material attached to a lower portion of the inverted generally U-shaped yoke member and extending beyond the yoke member end, forceful application of the shoes against the conductor effecting movement of the yoke member in a direction to produce moments of force about the centrally disposed hinge pin thereby resulting in closing of the jaws to substantially encompass the conductor, and withdrawal of forceful application of the shoes from against the conductor resulting in movement of the yoke member in an opposite direction due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; j. the sensing head adapted to be operatively associated with means for measuring the direct current passing through the conductor.

Claim 11

An instrument for measuring direct electrical current passing through a bar conductor which comprises: a. an elongate handle; b. a normally open tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor bar for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, generally arcuate, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle, the jaws when closed substantially encoMpassing the conductor for the current measuring; c. a moveable yoke assembly including an inverted generally U-shaped yoke member moveable on the handle and supporting the normally open tong-like jaws; d. hinge means hingedly mounting the jaws on the inverted generally U-shaped yoke member, said hinge means including two hinge plates secured to upper portions of the jaws and a substantially centrally disposed, with reference to the hinge means, pivot pin extending through the passageway of two axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member; e. links pivotally interconnecting and linking outer end portions of the hinge means hinge plates with outer end portions of a crossbar affixed in a slot in the lower portion of the handle; f. the crossbar affixed in the slot in the lower portion of the handle; g. the weight of instrument parts including the sensing head jaws and moveable yoke assembly maintaining the jaws in an open position when the shoes hereinafter specified are not forcefully applied against the conductor; h. means limiting the extent of opening of the jaws but allowing them to open sufficiently wide to enable said jaws to be positioned about the conductor; and i. shoes of a substantially non-electrically conductive material attached to a lower portion of and extending beyond the end of the inverted generally U-shaped yoke member, forceful application of the shoes against the conductor effecting movement of the moveable yoke assembly in a direction to produce moments of force about the centrally disposed pivot pin thereby resulting in closing of the jaws to substantially encompass the conductor, and withdrawal of the forceful application of the shoes from against the conductor resulting in movement of the moveably yoke assembly in an opposite direction due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a vertical orientation with the jaws below the handle; j. the sensing head adapted to be operatively associated with means for measuring the direct electrical current passing through the conductor.

Claim 12

An instrument for measuring direct electrical current passing through a bar conductor which comprises: a. an elongate handle; b. a normally open tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor bar for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, generally arcuate, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle, the jaws when closed substantially encoMpassing the conductor for the current measuring; c. a moveable yoke assembly including an inverted generally U-shaped yoke member moveable on the handle and supporting the normally open tong-like jaws; d. hinge means hingedly mounting the jaws on the inverted generally U-shaped yoke member, said hinge means including two hinge plates secured to upper portions of the jaws and a substantially centrally disposed, with reference to the hinge means, pivot pin extending through the passageway of two axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member; e. links pivotally interconnecting and linking outer end portions of the hinge means hinge plates with outer end portions of a crossbar affixed in a slot in the lower portion of the handle; f. the crossbar affixed in the slot in the lower portion of the handle; g. the weight of instrument parts including the sensing head jaws and moveable yoke assembly maintaining the jaws in an open position when the shoes hereinafter specified are not forcefully applied against the conductor; h. means limiting the extent of opening of the jaws but allowing them to open sufficiently wide to enable said jaws to be positioned about the conductor; and i. shoes of a substantially non-electrically conductive material attached to a lower portion of and extending beyond the end of the inverted generally U-shaped yoke member, forceful application of the shoes against the conductor effecting movement of the moveable yoke assembly in a direction to produce moments of force about the centrally disposed pivot pin thereby resulting in closing of the jaws to substantially encompass the conductor, and withdrawal of the forceful application of the shoes from against the conductor resulting in movement of the moveably yoke assembly in an opposite direction due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a vertical orientation with the jaws below the handle; j. the sensing head adapted to be operatively associated with means for measuring the direct electrical current passing through the conductor.

Claim 13

An instrument for measuring direct electrical current passing through a bar conductor which comprises: a. an elongate handle; b. a normally open, tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor bar for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, generally arcuate, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle which, when closed, substantially encompass the bar conductor for the current measuring; c. a moveable yoke assembly including a yoke sleeve moveable on the handle lower portion, a narrow width slot in a lower portion of said yoke sleeve, the slot being of larger width than that of the thickness of a crossbar affixed in a slot in the lower portion of a lower section of the handle, and an inverted generally U-shaped yoke member secured to an upper portion of the yoke sleeve, said yoke member being moveable on the handle together with said yoke sleeve; d. the crossbar affixed in the slot in the handle lower portion and disposed in the yoke sleeve slot; e. hinge means hingedly mounting the jaws on the inverted generally U-shaped yoke member, the hinge means including hinge plates secured to upper portions of the jaws and a substantially centrally disposed, with reference to the hinge means, pivot pin extending through the passageways of axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member; f. links pivotally Interconnecting and linking outer end portions of the hinge means hinge plates with outer end portions of the crossbar of (d); g. the weight of instrument parts including the sensing head jaws and moveably yoke assembly maintaining the jaws in an open position when the shoes hereafter specified are not forcefully applied against the conductor; h. means limiting the extent of opening of the jaws but allowing them to open sufficiently to enable said jaws to be positioned about the conductor; and i. shoes of a substantially non-electrically conductive material attached to a lower portion of and extending beyond the end of the inverted generally U-shaped yoke member, forceful application of the shoes against the conductor bar due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly effecting movement of the moveable yoke assembly in a direction to produce moments of force about the centrally disposed pivot pin thereby resulting in closing of the jaws to substantially encompass the conductor bar and withdrawal of the forceful application of the shoes from against the conductor bar resulting in movement of the moveable yoke assembly in an opposite direction due to the weight of instrument parts including the sensing head jaws and the moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; j. the sensing head adapted to be operatively associated with means for measuring the direct electrical current passing through the bar conductor.

Claim 14

An instrument for measuring direct electrical current passing through a bar conductor which comprises: a. an elongate handle; b. a normally open, tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor bar for current measuring purposes, said sensing head having normally open, conductor receptive, hinged, generally arcuate, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle which, when closed, substantially encompass the bar conductor for the current measuring; c. a moveable yoke assembly including a yoke sleeve moveable on the handle lower portion, a narrow width slot in a lower portion of said yoke sleeve, the slot being of larger width than that of the thickness of a crossbar affixed in a slot in the lower portion of a lower section of the handle, and an inverted generally U-shaped yoke member secured to an upper portion of the yoke sleeve, said yoke member being moveable on the handle together with said yoke sleeve; d. the crossbar affixed in the slot in the handle lower portion and disposed in the yoke sleeve slot; e. hinge means hingedly mounting the jaws on the inverted generally U-shaped yoke member, the hinge means including hinge plates secured to upper portions of the jaws and a substantially centrally disposed, with reference to the hinge means, pivot pin extending through the passageways of axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member; f. links pivotally Interconnecting and linking outer end portions of the hinge means hinge plates with outer end portions of the crossbar of (d); g. the weight of instrument parts including the sensing head jaws and moveably yoke assembly maintaining the jaws in an open position when the shoes hereafter specified are not forcefully applied against the conductor; h. means limiting the extent of opening of the jaws but allowing them to open sufficiently to enable said jaws to be positioned about the conductor; and i. shoes of a substantially non-electrically conductive material attached to a lower portion of and extending beyond the end of the inverted generally U-shaped yoke member, forceful application of the shoes against the conductor bar due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly effecting movement of the moveable yoke assembly in a direction to produce moments of force about the centrally disposed pivot pin thereby resulting in closing of the jaws to substantially encompass the conductor bar and withdrawal of the forceful application of the shoes from against the conductor bar resulting in movement of the moveable yoke assembly in an opposite direction due to the weight of instrument parts including the sensing head jaws and the moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; j. the sensing head adapted to be operatively associated with means for measuring the direct electrical current passing through the bar conductor.

Claim 15

The instrument of claim 7 wherein the sensing head normally open, conductor receptive tong-like jaws each comprise a non-magnetic core, and at least one electrically conductive wire coil on each core, the coils each having a multiplicity of windings and being electrically connected in series and adapted to be operatively electrically connected to the direct current measuring means.

Claim 16

The instrument of claim 8 wherein the wire of each coil is coated with a thin layer of an electrically insulating material.

Claim 17

The instrument of claim 9 wherein each tong-like jaw has an electrically insulating, corrosion resistant, mechanical attack-and abrasion-protecting non-magnetic layer of a material possessing such properties in said layer over the coil windings of each jaw.

Claim 18

The instrument of claim 10 wherein the bar conductor is a cathode bar in an electrolytic copper refinery tankhouse, and the tong-like jaws are so dimensioned as to readily pass between the cathode bar and immediately adjacent cathode bars to enable closing of the jaws about the first-mentioned cathode bar with the plane of said jaws being substantially normal to a major axis of the first-mentioned cathode bar.

Claim 19

The instrument of claim 11 wherein the material of the electrically insulating, corrosion resistant, mechanical attack-and abrasion-protecting, non-magnetic layer is a synthetic resin having such properties in said layer.

Claim 20

The instrument of claim 12 wherein the synthetic resin is an epoxy resin.

Claim 21

The instrument of claim 10 further characterized by having means effecting the automatic opening of the sensing head jaws and maintaining of said jaws in an open position when the shoes are not forcefully applied against the conductor when the instrument is in a generally vertical orientation with the jaws above the supporting means or in a generally horizontal orientation with the jaws lateral of the supporting means, as well as in a generally vertical orientation with the jaws below the supporting means.

Claim 22

The instrument of claim 14 wherein the automatic jaws opening effecting and jaws open position maintaining means is a helical spring disposed about a lower portion of the handle between and bearing against a shiftable collar locked on the handle lower portion and against the moveable yoke sleeve, the collar being locked at a desired position on the handle lower portion to provide a desired Degree of compression in the helical spring and a consequent desired degree of biasing of the moveable yoke sleeve sufficient to effect the automatic opening of the jaws and the maintaining of the jaws in the open position when the shoes are not forcefully applied against the conductor.

Claim 23

The instrument of claim 11 wherein generally horizontal and substantially parallel crossbars are attached to a lower portion of the legs of the inverted generally U-shaped yoke member, the crossbars each extending an appreciable distance laterally beyond the side edges of each leg, a lowermost edge of each crossbar when the instrument is in a generally vertical orientation with the jaws below the handle being above a lower edge of each shoe.

Claim 24

The instrument of claim 10 wherein the means limiting the opening extent of the jaws is a shiftable collar locked in a desired location on the yoke sleeve, and a cushion washer of resilient material is disposed between the shiftable collar locked on the yoke sleeve and the crossbar affixed in the slot in the handle lower portion and disposed in the yoke sleeve slot.

Claim 25

The instrument of claim 11 wherein the sensing head coils are operatively electrically connected to the direct current measuring means, said current measuring means comprising an ammeter-containing meter unit also containing circuit means.

Claim 26

The instrument of claim 18 wherein the ammeter-containing meter unit is mounted on the instrument handle.

Claim 27

The instrument of claim 19 wherein the ammeter-containing meter unit is mounted on a top portion of the instrument handle.

Claim 28

The instrument of claim 20 wherein the meter unit has a short length of tube of larger diameter than that of a top portion of the instrument handle secured to a back side plate of a casing of the meter unit, the meter unit being removably mounted on a top portion of the instrument handle by means of said tube being disposed over the top portion of the handle.

Claim 29

The instrument of claim 7 wherein attrition-preventing plates are secured to confronting end faces of the tong-like jaws.

Claim 30

An instrument for measuring direct current passing through a bar conductor which comprises: a. an elongate supporting tube including an upper tubular section, a lower tubular section, and flexible joint means uniting the lower portion of the upper section with the upper portion of the lower section; b. a normally open, tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor bar for current measuring purposes, said sensing head having normally open, hinged, tong-like automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle which, when closed, substantially encompass the conductor for the current measuring; c. a moveable yoke assembly including a yoke sleeve moveable on the supporting tube lower section, a narrow width slot in a lower portion of said sleeve, the slot being of larger width than the thickness of a crossbar affixed in a slot in the lower portion of the supporting tube lower section and disposed in the yoke sleeve slot, and an inverted generally U-shaped yoke member secured to an upper portion of the yoke sleeve, said yoke member being moveable on the supporting tube lower section with the yoke sleeve; d. the crossbar affixed in the slot in the supporting tube lower tubular section and disposed in the yoke sleeve slot, said crossbar having an aperture in each opposite end portion; e. hinge means including a substantially centrally disposed, with reference to the hinge means, pivot pin extending through passageways of two axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member, and the hinge plates secured to upper portions of the tong-like jaws, each hinge plate having two spaced apart, axially aligned annulaR members secured to a generally downwardly extending outer end portion of said hinge plate; f. fastening members securing the hinge plates to the upper portions of the tong-like jaws; g. a shiftable collar slideable on the yoke sleeve, and means locking the collar at a predetermined location on the sleeve, said collar limiting the extent of opening of the tong-like jaws by abutting against the crossbar after a predetermined distance of downward movement of the yoke sleeve and the inverted generally U-shaped yoke member secured thereto; h. link arms each having a longitudinally slotted end portion with transverse axially aligned apertures through the slotted end portion and an aperture in the opposite end portion thereof, each link arm pivotally connected to the crossbar by receiving an apertured end portion of the crossbar in its slotted end portion in such manner that the crossbar apertures and link arm slotted end portion apertures register, and pivot pins through the registering apertures of the crossbars and of the slotted and apertured linkage arm end portions, and each link arm also pivotally connected at its opposite apertured end portion to each hinge plate outer end portion by a pivot pin through registering apertures of the hinge plate axially aligned annular members and of said opposite apertured end portion of the link arm, said opposite apertured end portion of the link arm being positioned between the spaced axially aligned annular members of the hinge plate outer end portion; i. the weight of instrument parts including the sensing head jaws and moveable yoke assembly maintaining the jaws in an open position when the shoes hereafter specified are not forcefully applied against the conductor; and j. shoes of substantially non-electrically conductive material attached to a lower end portion of the inverted generally U-shaped yoke member legs and extending beyond the lower ends of said yoke member legs, the shoes contacting the bar conductor upon downward lowering movement of the instrument whereby due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly, the shoes, inverted generally U-shaped yoke member and yoke sleeve move upwardly to produce moments of force about the centrally disposed pivot pin thereby resulting in movement of the jaws to a closed position substantially encompassing the bar conductor and withdrawal of forceful application of the shoes from the bar conductor by an upward lifting movement of the instrument resulting in movement downwardly of the shoes, yoke sleeve and the inverted generally U-shaped yoke member due to the weight of instrument parts including the sensing head jaws and moveably yoke assembly thereby resulting in movement of the jaws to their normally open, conductor receptive position when the instrument is in a generally vertical orientation with the jaws below the supporting tube; k. the sensing head adapted to be electrically connected to an ammeter-containing unit also containing circuit means for measuring the current passing through the conductor.

Claim 31

An instrument for measuring direct current passing through a bar conductor which comprises: a. an elongate supporting tube including an upper tubular section, a lower tubular section, and flexible joint means uniting the lower portion of the upper section with the upper portion of the lower section; b. a normally open, tong-like sensing head capable of utilizing a magnetic field created by the current passing through the conductor bar for current measuring purposes, said sensing head having normally open, hinged, tong-like automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the handle which, when closed, substantially encompass the conductor for the current measuring; c. a moveable yoke assembly including a yoke sleeve moveable on the supporting tube lower section, a narrow width slot in a lower portion of said sleeve, the slot being of larger width than the thickness of a crossbar affixed in a slot in the lower portion of the supporting tube lower section and disposed in the yoke sleeve slot, and an inverted generally U-shaped yoke member secured to an upper portion of the yoke sleeve, said yoke member being moveable on the supporting tube lower section with the yoke sleeve; d. the crossbar affixed in the slot in the supporting tube lower tubular section and disposed in the yoke sleeve slot, said crossbar having an aperture in each opposite end portion; e. hinge means including a substantially centrally disposed, with reference to the hinge means, pivot pin extending through passageways of two axially aligned sleeves each affixed to an inner end portion of a different hinge plate and through registering orifices in the inverted generally U-shaped yoke member, and the hinge plates secured to upper portions of the tong-like jaws, each hinge plate having two spaced apart, axially aligned annulaR members secured to a generally downwardly extending outer end portion of said hinge plate; f. fastening members securing the hinge plates to the upper portions of the tong-like jaws; g. a shiftable collar slideable on the yoke sleeve, and means locking the collar at a predetermined location on the sleeve, said collar limiting the extent of opening of the tong-like jaws by abutting against the crossbar after a predetermined distance of downward movement of the yoke sleeve and the inverted generally U-shaped yoke member secured thereto; h. link arms each having a longitudinally slotted end portion with transverse axially aligned apertures through the slotted end portion and an aperture in the opposite end portion thereof, each link arm pivotally connected to the crossbar by receiving an apertured end portion of the crossbar in its slotted end portion in such manner that the crossbar apertures and link arm slotted end portion apertures register, and pivot pins through the registering apertures of the crossbars and of the slotted and apertured linkage arm end portions, and each link arm also pivotally connected at its opposite apertured end portion to each hinge plate outer end portion by a pivot pin through registering apertures of the hinge plate axially aligned annular members and of said opposite apertured end portion of the link arm, said opposite apertured end portion of the link arm being positioned between the spaced axially aligned annular members of the hinge plate outer end portion; i. the weight of instrument parts including the sensing head jaws and moveable yoke assembly maintaining the jaws in an open position when the shoes hereafter specified are not forcefully applied against the conductor; and j. shoes of substantially non-electrically conductive material attached to a lower end portion of the inverted generally U-shaped yoke member legs and extending beyond the lower ends of said yoke member legs, the shoes contacting the bar conductor upon downward lowering movement of the instrument whereby due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly, the shoes, inverted generally U-shaped yoke member and yoke sleeve move upwardly to produce moments of force about the centrally disposed pivot pin thereby resulting in movement of the jaws to a closed position substantially encompassing the bar conductor and withdrawal of forceful application of the shoes from the bar conductor by an upward lifting movement of the instrument resulting in movement downwardly of the shoes, yoke sleeve and the inverted generally U-shaped yoke member due to the weight of instrument parts including the sensing head jaws and moveably yoke assembly thereby resulting in movement of the jaws to their normally open, conductor receptive position when the instrument is in a generally vertical orientation with the jaws below the supporting tube; k. the sensing head adapted to be electrically connected to an ammeter-containing unit also containing circuit means for measuring the current passing through the conductor.

Claim 32

An instrument for measuring electrical current passing through a conductor, which comprises: a. supporting means; b. a normally open, sensing head capable of utilizing a magnetic field created by the current through the conductor for current measuring purposes, said sensing head having normally open, pivotally mounted, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means of a non-retentive magnetic material, the jaws when closed substantially encompassing the conductor for the current measuring; c. means moveable on the supporting means of (a) and supporting the normally open sensing head jaws; d. means pivotally mounting the jaws on the last-mentioned moveable supporting means; e. means connecting outer end portions of the pivotal jaw mounting means with the supporting means; f. means maintaining the jaws in an open position when a contacting means hereinafter specified is not forcefully applied against the solid surface; and g. contacting means attached to the moveable yoke assembly, forceful application of the contacting means against a solid surface effecting movement of the moveable supporting means in a direction to result in the automatic closing of the jaws to substantially encompass the conductor and withdrawal of the forceful contacting means application from against the solid surface resulting in movement of the moveable supporting means in a different direction when the instrument is in a generally vertical orientation with the jaws below the supporting means to effect the automatic opening of the jaws; h. the sensing head adapted to be operatively associated with means for measuring the electrical current passing through the conductor.

Claim 33

An instrument for measuring electrical current passing through a conductor, which comprises: a. supporting means; b. a normally open, sensing head capable of utilizing a magnetic field created by the current through the conductor for current measuring purposes, said sensing head having normally open, pivotally mounted, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means of a non-retentive magnetic material, the jaws when closed substantially encompassing the conductor for the current measuring; c. means moveable on the supporting means of (a) and supporting the normally open sensing head jaws; d. means pivotally mounting the jaws on the last-mentioned moveable supporting means; e. means connecting outer end portions of the pivotal jaw mounting means with the supporting means; f. means maintaining the jaws in an open position when a contacting means hereinafter specified is not forcefully applied against the solid surface; and g. contacting means attached to the moveable yoke assembly, forceful application of the contacting means against a solid surface effecting movement of the moveable supporting means in a direction to result in the automatic closing of the jaws to substantially encompass the conductor and withdrawal of the forceful contacting means application from against the solid surface resulting in movement of the moveable supporting means in a different direction when the instrument is in a generally vertical orientation with the jaws below the supporting means to effect the automatic opening of the jaws; h. the sensing head adapted to be operatively associated with means for measuring the electrical current passing through the conductor.

Claim 34

The instrument of claim 24 wherein the sensing head is operatively associated with the current measuring means and said current measuring means comprises a permanent magnet needle rotatably mounted on a pivot disposed in a cavity formed in at least one of the non-retentive magnetic jaws, said magnet needle being restrained in a position substantially normal to induced flux lines in the jaw, interaction between the induced flux of the jaw and the permanent magnet needle flux causing the magnet needle to turn on its pivot an extent proportional to the amount of electrical current through the bar conductor.

Claim 35

An instrument for measuring direct electrical current passing through a bar conductor which comprises: a. supporting means; b. a normally open tong-like sensing head capable of utilizing a magnetic field created by the current through the conductor for current measuring purposes, said sensing head having normally open, hinged, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means, of a non-retentive magnetic material, the jaws when closed substantially encompassing the conductor for the current measuring; c. moveable yoke means including an inverted generally U-shaped yoke member moveable on the supporting means and supporting the normally open sensing head jaws; d. hinge means including a substantially centrally disposed, with reference to the hinge means, pivot pin hingedly mounting the jaws on the moveable yoke means yoke member; e. links pivotally interconnecting and linking outer end portions of the hinge means with a lower portion of the supporting means; f. means maintaining the jaws in an open position when shoes hereafter specified are not forcefully applied against the solid surface; g. means limiting the extent of opening of the jaws but allowing them to open sufficiently wide to enable the jaws to be positioned about the conductor; and h. shoes of a substantially non-electrically conductive material attached to a lower portion of the yoke means yoke member and extending beyond the yoke member end, forceful application of the shoes against a solid surface effecting movement of the yoke member in a direction to produce moments of force about the centrally disposed hinge pin thereby resulting in closing of the jaws to substantially encompass the conductor bar and withdrawal of forceful application of the shoes from against the solid surface resulting in movement of the yoke member in an opposite direction due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a generally vertical position with the jaws below the supporting means; i. the sensing jaws adapted to be operatively associated with magnetic flux-utilizing current measuring means for measuring the electrical current passing through the conductor.

Claim 36

An instrument for measuring direct electrical current passing through a bar conductor which comprises: a. supporting means; b. a normally open tong-like sensing head capable of utilizing a magnetic field created by the current through the conductor for current measuring purposes, said sensing head having normally open, hinged, tong-like, automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means, of a non-retentive magnetic material, the jaws when closed substantially encompassing the conductor for the current measuring; c. moveable yoke means including an inverted generally U-shaped yoke member moveable on the supporting means and supporting the normally open sensing head jaws; d. hinge means including a substantially centrally disposed, with reference to the hinge means, pivot pin hingedly mounting the jaws on the moveable yoke means yoke member; e. links pivotally interconnecting and linking outer end portions of the hinge means with a lower portion of the supporting means; f. means maintaining the jaws in an open position when shoes hereafter specified are not forcefully applied against the solid surface; g. means limiting the extent of opening of the jaws but allowing them to open sufficiently wide to enable the jaws to be positioned about the conductor; and h. shoes of a substantially non-electrically conductive material attached to a lower portion of the yoke means yoke member and extending beyond the yoke member end, forceful application of the shoes against a solid surface effecting movement of the yoke member in a direction to produce moments of force about the centrally disposed hinge pin thereby resulting in closing of the jaws to substantially encompass the conductor bar and withdrawal of forceful application of the shoes from against the solid surface resulting in movement of the yoke member in an opposite direction due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a generally vertical position with the jaws below the supporting means; i. the sensing jaws adapted to be operatively associated with magnetic flux-utilizing current measuring means for measuring the electrical current passing through the conductor.

Claim 37

The instrument of claim 26 wherein the sensing head is operatively assOciated with the current measuring means and said current measuring means comprises a permanent magnet needle rotatably mounted on a pivot disposed in a cavity form ed in at least one of the non-retentive magnetic jaws, said magnet needle being restrained in a position substantially normal to induced flux lines in the jaw, interaction between the induced flux of the jaw and the permanent magnet needle flux causing the magnet needle to turn on its pivot an extent proportional to the amount of electrical current through the bar conductor.

Claim 38

An instrument for measuring direct electrical current passing through a bar conductor which comprises: a. an elongate handle; b. a normally open tong-like sensing head capable of utilizing a magnetic field created by the current through the conductor for current measuring purposes, said sensing head having normally open, hinged, tong-like automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means, of a non-retentive magnetic material, the jaws when closed substantially encompassing the conductor for the current measuring; c. moveable yoke means including an inverted generally U-shaped yoke member moveable on the elongate handle and supporting the normally open sensing head jaws; d. hinge means hingedly mounting the jaws on the moveable yoke means yoke member, said hinge means including hinge plates secured to upper portions of the jaws, and a substantially centrally disposed, with reference to the hinge means, pivot pin extending through at least one sleeve affixed to inner end portions of the hinge plates and through registering orifices in the inverted generally U-shaped yoke member; e. links pivotally interconnecting and linking outer end portions of the hinge means hinge plates with outer end portions of a crossbar affixed in a slot in a lower portion of the handle; f. the crossbar affixed in the slot in the handle lower portion; g. the weight of instrument parts including the sensing head jaws and the moveable yoke means maintaining the tong-like jaws in an open position when shoes hereinafter specified ar not forcefully applied against the conductor; h. means limiting the extent of opening of the jaws but allowing them to be opened sufficiently wide to enable the jaws to be positioned about the conductor; and i. shoes of a substantially non-electrically conductive material attached to a lower portion of the inverted generally U-shaped yoke member and extending beyond the yoke member end, forceful application of the shoes against the conductor due to the weight of instrument parts including the sensing head jaws and moveable yoke means effecting movement of the yoke member in a direction to produce moments of force about the pivot pin thereby resulting in closing of the jaws about the conductor and withdrawal of forceful application of the shoes from the conductor resulting in movement of the yoke member in an opposite direction due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; j. the sensing head adapted to be operatively associated with means for measuring the direct current passing through the conductor.

Claim 39

An instrument for measuring direct electrical current passing through a bar conductor which comprises: a. an elongate handle; b. a normally open tong-like sensing head capable of utilizing a magnetic field created by the current through the conductor for current measuring purposes, said sensing head having normally open, hinged, tong-like automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means, of a non-retentive magnetic material, the jaws when closed substantially encompassing the conductor for the current measuring; c. moveable yoke means including an inverted generally U-shaped yoke member moveable on the elongate handle and supporting the normally open sensing head jaws; d. hinge means hingedly mounting the jaws on the moveable yoke means yoke member, said hinge means including hinge plates secured to upper portions of the jaws, and a substantially centrally disposed, with reference to the hinge means, pivot pin extending through at least one sleeve affixed to inner end portions of the hinge plates and through registering orifices in the inverted generally U-shaped yoke member; e. links pivotally interconnecting and linking outer end portions of the hinge means hinge plates with outer end portions of a crossbar affixed in a slot in a lower portion of the handle; f. the crossbar affixed in the slot in the handle lower portion; g. the weight of instrument parts including the sensing head jaws and the moveable yoke means maintaining the tong-like jaws in an open position when shoes hereinafter specified ar not forcefully applied against the conductor; h. means limiting the extent of opening of the jaws but allowing them to be opened sufficiently wide to enable the jaws to be positioned about the conductor; and i. shoes of a substantially non-electrically conductive material attached to a lower portion of the inverted generally U-shaped yoke member and extending beyond the yoke member end, forceful application of the shoes against the conductor due to the weight of instrument parts including the sensing head jaws and moveable yoke means effecting movement of the yoke member in a direction to produce moments of force about the pivot pin thereby resulting in closing of the jaws about the conductor and withdrawal of forceful application of the shoes from the conductor resulting in movement of the yoke member in an opposite direction due to the weight of instrument parts including the sensing head jaws and moveable yoke assembly thereby resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; j. the sensing head adapted to be operatively associated with means for measuring the direct current passing through the conductor.

Claim 40

The instrument of claim 28 wherein the sensing head is operatively associated with the current measuring means and said current measuring means comprises a permanent magnet needle rotatably mounted on a pivot disposed in a cavity formed in at least one of the non-retentive magnetic jaws, said magnet needle being restrained in a position substantially normal to induced flux lines in the jaw, interaction between the induced flux of the jaw and the permanent magnet needle flux causing the magnet needle to turn on its pivot an extent proportional to the amount of electrical current througH the bar conductor.

Claim 41

An instrument for measuring electrical current passing through a conductor, which comprises: a. supporting means; b. a normally open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having hinged, normally open, conductor receptive automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means, the jaws when closed substantially encompassing the conductor for the current measuring; c. an immovable inverted generally U-shaped first yoke including first yoke members secured at their generally horizontal upper end portions to a lower portion of the supporting means, and at their generally vertical lower end portions to outer end portions of hinge means mounting the jaws; d. an immovable inverted generally U-shaped second yoke including second yoke members secured at their generally horizontal upper end portions to the generally horizontal upper end portions of the first yoke members or to a lower portion of the supporting means at points of securing spaced from that of the first yoke members, said second yoke members having generally vertical intermediate portions and generally vertical lower end portions below the hinge means, said second yoke members having spaced, opposite, open-ended slots in a lower portion thereof, the second yoke members open-ended slots registering with an aperture through the hinge means; e. the hinge means mounting the sensing head jaws, said hinge means having the aperture extending therethrough; f. a substantially centrally disposed, with reference to the hinge means, pivot pin disposed in the aperture through the hinge means, the pivot pin also extending through and moveable in the slot of said second yoke members and through spaced, opposite, orifices in lower generally vertical portions of third yoke members of a moveable third yoke; g. a moveable inverted generally U-shaped third yoke including the third yoke members having the spaced, opposite orifices in the lower generally vertical portions thereof, said third yoke being unsecured at its generally horizontal upper end portion and the generally vertical lower portion of said third yoke being spaced laterally outwardly of the second yoke and substantially parallel to the second yoke generally vertical intermediate and lower end portions; h. means securing said third yoke and hence said second yoke on the pivot pin; i. means maintaining the jaws in an open position when shoes hereafter specified are not applied against the conductor; and j. shoes attached to a lower portion of said third yoke members and extending beyond lower ends thereof, forceful application of the shoes against the conductor resulting in closing of the jaws to substantially encompass the conductor and withdrawal of forceful application of the shoes from against the conductor resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means; k. the sensing head adapted to be operatively associated with means for measuring the current passing through the conductor.

Claim 42

An instrument for measuring electrical current passing through a conductor, which comprises: a. supporting means; b. a normally open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having hinged, normally open, conductor receptive automatically closeable and automatically openable jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means, the jaws when closed substantially encompassing the conductor for the current measuring; c. an immovable inverted generally U-shaped first yoke including first yoke members secured at their generally horizontal upper end portions to a lower portion of the supporting means, and at their generally vertical lower end portions to outer end portions of hinge means mounting the jaws; d. an immovable inverted generally U-shaped second yoke including second yoke members secured at their generally horizontal upper end portions to the generally horizontal upper end portions of the first yoke members or to a lower portion of the supporting means at points of securing spaced from that of the first yoke members, said second yoke members having generally vertical intermediate portions and generally vertical lower end portions below the hinge means, said second yoke members having spaced, opposite, open-ended slots in a lower portion thereof, the second yoke members open-ended slots registering with an aperture through the hinge means; e. the hinge means mounting the sensing head jaws, said hinge means having the aperture extending therethrough; f. a substantially centrally disposed, with reference to the hinge means, pivot pin disposed in the aperture through the hinge means, the pivot pin also extending through and moveable in the slot of said second yoke members and through spaced, opposite, orifices in lower generally vertical portions of third yoke members of a moveable third yoke; g. a moveable inverted generally U-shaped third yoke including the third yoke members having the spaced, opposite orifices in the lower generally vertical portions thereof, said third yoke being unsecured at its generally horizontal upper end portion and the generally vertical lower portion of said third yoke being spaced laterally outwardly of the second yoke and substantially parallel to the second yoke generally vertical intermediate and lower end portions; h. means securing said third yoke and hence said second yoke on the pivot pin; i. means maintaining the jaws in an open position when shoes hereafter specified are not applied against the conductor; and j. shoes attached to a lower portion of said third yoke members and extending beyond lower ends thereof, forceful application of the shoes against the conductor resulting in closing of the jaws to substantially encompass the conductor and withdrawal of forceful application of the shoes from against the conductor resulting in opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the supporting means; k. the sensing head adapted to be operatively associated with means for measuring the current passing through the conductor.

Claim 43

The instrument of claim 30 wherein the sensing head normally open, tong-like jaws each include a non-magnetic core, and at least one conductive wire coil on each core, the coils each including a multiplicity of windings and connected in series and to a current measuring means.

Claim 44

The instrument of claim 31 wherein the wire of each coil is coated with a layer of electrically insulating material.

Claim 45

The instrument of claim 32 wherein each jaw has an electrically insulating, corrosion resistant, mechanical attack and abrasion-protecting non-magnetic layer of a material possessing such properties in said layer over the coil windings of each jaw.

Claim 46

The instrument of claim 33 wherein the materiAl of the electrically insulating, corrosion resistant, mechanical attack and abrasion-protecting, non-magnetic layer is a synthetic resin having such properties in said layer.

Claim 47

An instrument for measuring direct electrical current passing through a conductor, which comprises: a. an elongate handle; b. a normally open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having hinged, normally open, automatically closeable and automatically openable, jaws when the instrument is in a generally vertical orientation with the jaws below the handle, the jaws when closed substantially encompassing the conductor for the current measuring; c. an immovable inverted generally U-shaped first yoke including first yoke members secured at their generally horizontal upper end portions to a lower portion of the supporting means, and at their generally vertical lower end portions to outer end portions of hinge means mounting the jaws; d. an immovable inverted generally U-shaped second yoke including second yoke members secured at their generally horizontal upper end portions to the generally horizontal upper end portions of the first yoke members or to a lower portion of the supporting means at points of securing spaced from that of the first yoke members, said second yoke members having generally vertical intermediate portions and generally vertical lower end portions below the hinge means, said second yoke members having spaced, opposite, open-ended slots in a lower portion thereof, the second yoke members open-ended slots registering with registering apertures through the hinge means hinge plates hereafter specified; e. the hinge means mounting the sensing head jaws, said hinge means comprising the hinge plates secured to an upper portion of the jaws and having the registering apertures extending therethrough; f. a substantially centrally disposed, with reference to the hinge means, pivot pin disposed in the apertures through the hinge plates, the pivot pin also extending through and moveable in the slot of said second yoke members and through spaced, opposite, orifices in lower generally vertical portions of third yoke members of a moveable third yoke; g. a moveable inverted generally U-shaped third yoke including the third yoke members having the spaced opposite orifices in the lower generally vertical portions thereof, said third yoke being unsecured at its generally horizontal upper end portion and the generally vertical lower portion of said third yoke being spaced laterally outwardly of the second yoke and substantially parallel to the second yoke generally vertical intermediate and lower end portions; h. means securing said third yoke and hence said second yoke on the pivot pin; i. the weight of instrument parts including the sensing head jaws and the third yoke maintaining the jaws in an open position when shoes hereafter specified are not forcefully applied against the conductor; j. shoes of a substantially non-electrically conductive material attached to a lower portion of said third yoke members and extending beyond lower ends thereof, forceful application of the shoes against the conductor resulting in upward movement of the substantially centrally disposed pivot pin in the second yoke slot aperture thereby resulting in the automatic closing of the jaws to substantially encompass the conductor and withdrawal of the forceful application of the shoes from against the conductor resulting in downward movement of the pivot pin in the second yoke slots thereby resulting in the automatic opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; and k. means operatively associated with the sensing head for measuring the current passing through the conductor.

Claim 48

An instrument for measuring direct electrical current passing through a conductor, which comprises: a. an elongate handle; b. a normally open sensing head capable of utilizing a magnetic field created by the current passing through the conductor for current measuring purposes, said sensing head having hinged, normally open, automatically closeable and automatically openable, jaws when the instrument is in a generally vertical orientation with the jaws below the handle, the jaws when closed substantially encompassing the conductor for the current measuring; c. an immovable inverted generally U-shaped first yoke including first yoke members secured at their generally horizontal upper end portions to a lower portion of the supporting means, and at their generally vertical lower end portions to outer end portions of hinge means mounting the jaws; d. an immovable inverted generally U-shaped second yoke including second yoke members secured at their generally horizontal upper end portions to the generally horizontal upper end portions of the first yoke members or to a lower portion of the supporting means at points of securing spaced from that of the first yoke members, said second yoke members having generally vertical intermediate portions and generally vertical lower end portions below the hinge means, said second yoke members having spaced, opposite, open-ended slots in a lower portion thereof, the second yoke members open-ended slots registering with registering apertures through the hinge means hinge plates hereafter specified; e. the hinge means mounting the sensing head jaws, said hinge means comprising the hinge plates secured to an upper portion of the jaws and having the registering apertures extending therethrough; f. a substantially centrally disposed, with reference to the hinge means, pivot pin disposed in the apertures through the hinge plates, the pivot pin also extending through and moveable in the slot of said second yoke members and through spaced, opposite, orifices in lower generally vertical portions of third yoke members of a moveable third yoke; g. a moveable inverted generally U-shaped third yoke including the third yoke members having the spaced opposite orifices in the lower generally vertical portions thereof, said third yoke being unsecured at its generally horizontal upper end portion and the generally vertical lower portion of said third yoke being spaced laterally outwardly of the second yoke and substantially parallel to the second yoke generally vertical intermediate and lower end portions; h. means securing said third yoke and hence said second yoke on the pivot pin; i. the weight of instrument parts including the sensing head jaws and the third yoke maintaining the jaws in an open position when shoes hereafter specified are not forcefully applied against the conductor; j. shoes of a substantially non-electrically conductive material attached to a lower portion of said third yoke members and extending beyond lower ends thereof, forceful application of the shoes against the conductor resulting in upward movement of the substantially centrally disposed pivot pin in the second yoke slot aperture thereby resulting in the automatic closing of the jaws to substantially encompass the conductor and withdrawal of the forceful application of the shoes from against the conductor resulting in downward movement of the pivot pin in the second yoke slots thereby resulting in the automatic opening of the jaws when the instrument is in a generally vertical orientation with the jaws below the handle; and k. means operatively associated with the sensing head for measuring the current passing through the conductor.