Sliding contact mechanical/electrical displacement transducer

Claim 2

Apparatus as in Claim 1 wherein said sensor means comprises an insulative coating disposed over said one surface area.

Claim 3

Apparatus as in Claim 2 wherein said sensor means comprises a substrate having a first surface area, said carrying member being in slidable contact with said first surface area, and an array of detecting means disposed at the first surface for detecting the proximity of the field-producing element relative to the detecting means and thus the displacement of said object.

Claim 4

Apparatus as in Claim 3 wherein said sensor means further comprises means for supplying a voltage to said field-producing element to produce an electric field emanating therefrom, and wherein said detecting means each comprises a field-effect transistor having a source region, a drain region, a channel region positioned between the source region and drain region on the first surface under the path of movement of the conductive element, said insulation coating overlying the source region, drain region and channel region, said field-effect transistor thereby producing an output signal when the field-producing element is moved to within a certain proximity of said field-effect transistor.

Claim 5

Apparatus as in Claim 4 wherein said substrate is composed of silicon, wherein said insulation coating is composed of material selected from the group consisting of silicon nitride, silicon dioxide, and diamond film.

Claim 6

Apparatus as in Claim 3 wherein said field-producing element is magnetized, and wherein said detecting means each further comprises a split-drain magnetic field-effect transistor having a source region, two drain regions, and a channel region positioned between the source region and two drain regions at the first surface under path of movement of the field-producing element, said split-drain magnetic field-effect transistor thereby producing an output signal when the field-producing element is moved to within a certain proximity of said magnetic field-effect transistor.

Claim 7

Apparatus as in Claim 6 wherein said substrate is composed of silicon, and wherein said conductive element is composed of magnetized material.

Claim 8

Apparatus as in Claim 3 wherein said sensor means further comprises an array of conductive strips of material disposed on the first surface and extending under the path of movement of the field-producing element, said insulative coating overlying the array of conductive strips, and means for supplying an electrical voltage to said field-producing element, and wherein said detecting means each comprises a field-effect transistor having a gate region coupled to a corresponding conductive strip so that the field-effect transistor produces an output signal when the field-producing element is positioned within a certain proximity of the conductive strip.

Claim 9

Apparatus as in Claim 3 wherein said sensor means further comprises electret means for producing an electric field said electret means being disposed on the first surface to extend under the path of movement of the field-producing element, wherein said field-producing element is grounded, and wherein said detecting means each comprises a field-effect transistor having a source region, a drain region, and a channel region positioned between the source region and drain region under the electret means, said field-effect transducer thereby producing an output signal when the field-producing element is positioned within a certain proximity of the field-effect transistor to deflect away from the channel region of the field-effect transistor the electric field normally impinging thereon from the electret means.

Claim 10

Apparatus as in Claim 9 wherein said electret means comprises a strip of polytetrafluoroethylene containing electrons and disposed over at least the channel region of each field-effect transistor and under the path of movement of the field-producing element.

Claim 11

Apparatus as in Claims 3, 4, 6, 8, or 9 wherein said array of detecting means is formed generally in a partial circle on the substrate, wherein said object is disposed to rotate above the substrate, and wherein the carrying member is disposed to move in sliding contact over the array of detecting means when the object is rotated.

Claim 12

Apparatus as in Claim 3 wherein said array of detecting means is disposed generally in a line on the first surface in the direction of movement of the field-producing element, each of said detecting means including means for producing a signal indicative of the field-producing element being within a certain proximity of said each detecting means.

Claim 13

Apparatus as in Claim 12 wherein said sensor means further comprises additional detecting means disposed on the first surface, along with said array of detecting means, at selected intersections of an imaginary grid, for producing signals representing digital values indicative that the field-producing element is positioned within a certain proximity of certain combinations of detecting means.

Claim 14

Apparatus as in Claim 2 wherein said carrying member and field-producing element comprise a flexible foil tab coupled at one end to said object, the other end of which is disposed in slidable contact with said insulative coating to slide thereover as the object is moved.

Claim 15

Apparatus as in Claim 2 wherein said sensor means comprises a substrate having a first surface area, and a generally circular array of detecting elements disposed at the first surface area for producing signals when the field-producing element is within a certain proximity of said detecting elements, and wherein said carrying member comprises a disk means disposed to rotate in sliding contact with the insulative coating as the object is moved to thereby carry the field-producing element in a path which traverses the array of detecting elements.

Claim 16

Apparatus as in Claim 15 wherein said field-producing element comprises a resilient strip of material depending downwardly from the disk means so that the lower end of the strip contacts and slides over the insulative layer in said path as the desk means is rotated.

Claim 17

Apparatus as in Claim 15 wherein said field-producing element comprises an elongate conductor disposed radially on the underside of said disk means to transverse over said path as the disk means is rotated.

Claim 18

Apparatus as in Claim 17 wherein said disk means includes downwardly projecting protuberances which contact and slide over the first surface area as the disk means is rotated, so that said conductor is maintained out of contact with the first surface.

Claim 19

Apparatus as in Claim 18 wherein said substrate further includes circularly disposed grooves for receiving said protuberances to allow sliding therein as the disk means is rotated.

Claim 20

Apparatus as in Claim 15 wherein said field-producing element comprises a strip of material formed in a partial circle on the underside of said disk means to pass over said path as the disk means is rotated.

Claim 21

Apparatus as in Claim 20 wherein said sensor means further comprises means for developing a capacitance between the substrate and said strip of material so that said strip of material produces an electric field which impinges on the detector elements over which the strip of material passes, and wherein said detecting elements each comprise field-effect transistors for producing output signals when the electric field produced by the strip of material impinges on the field-effect transistors.

Claim 22

Apparatus as in Claim 3 wherein said array of detecting means is disposed generally in a line on the first surface area in the direction of movement of the field-producing element, and wherein said carrying member includes downwardly projecting protuberances which contact and slide over the first surface area as the carrying member is moved.

Claim 23

Apparatus as in Claim 22 wherein said protuberances comprise a pair of generally parallel rails, and wherein said substrate includes a pair of generally parallel grooves formed in said first surface area for receiving said pair of rails to allow sliding therein.

Claim 24

Apparatus as in Claim 23 wherein said protuberances comprise at least three space-apart, downwardly projecting nipples.

Claim 25

Position determining apparatus comprising an article whose position is to be determined, a force field developing means disposed to selectively move over a surface loci of points as the article is moved, and sensor means defining a surface area coincident with said loci of points such that said force field developing means moves in sliding contact with said surface area, for producing signals whose magnitudes are proportional to the proximity of the force field developing means to respective points of said loci of points, and thus indicative of the position of the article.

Claim 26

A displacement transducer for converting position of an object into an electrical signal representation comprising a sensor having a surface area defined thereon for developing an electrical signal whose value is dependent upon the location over the surface area of an emitter element having a certain electrical/magnetic characteristic, an insulation layer overlying the surface area, and an emitter element having said certain electrical/magnetic characteristics, and disposed in contact with said insulation layer to slide thereover as the object is moved.

Claim 27

Rotary displacement measuring apparatus comprising an axle whose rotary displacement is to be measured, said axle mounted to rotate about its long axis, means mounted on the axle to extend laterally therefrom and rotate as the axle is rotated, and for producing a force field emanating downwardly therefrom, a plurality of sensors arranged generally in a circle under the path of movement of the force field producing means for producing signals whose magnitudes vary with variation in proximity of the force field to the sensors, and an insulative coating overlying said sensors, said force field producing means being disposed in sliding contact with said insulative coating.

Claim 28

Apparatus as in Claim 27 wherein said force field producing means comprises a disk mounted generally at its center to the axle, and an emitter element formed on the underside of the disk to produce a force field directed downwardly, and wherein said sensors are arranged generally in series in said circle.

Claim 29

Apparatus as in Claim 28 wherein said emitter element comprises a resilient tab extending downwardly from the disk to contact and slide over the insulative coating.

Claim 30

Apparatus as in Claim 28 wherein said emitter element comprises a conductive strip of material disposed to extend radially outwardly on the underside of the disk

Claim 31

Apparatus as in Claim 27 wherein said force field producing means comprises a semicircular plate having a generally straight side and a semicircular side, and mounted generally at the center of its straight side to the axle such that when the axle is rotated, the semicircular side of the plate moves in a circle about the axle, and wherein said sensors are arranged to extend in partial circles, some concentrically with at least portions of others.

Claim 32

Apparatus as in Claim 27 wherein said force field producing means comprises mounting means attached to the axle, emitter means for producing a force field emanating downwardly therefrom, and spring means for resiliently coupling the emitter means to the mounting means so that the emitter means is disposed in sliding contact with said insulative coating, said spring means allowing relative movement of the emitter means toward and away from the mounting means.

Claim 33

A displacement transducer for measuring movement of an object, said transducer comprising a pair of substrates disposed in facing, contacting relationship, one of which is coupled to said object to move and slide over the other substrate when the object moves, a plurality of force field emitters spaced apart longitudinally along the facing surface of a first substrate, each for producing a force field whose intensity is greater with closer proximity to said each emitter, a multiplicity of force field detector elements spaced apart longitudinally along the facing surface of a second substrate so that for a certain range of movement of said first substrate relative to the second, each detector element at some point over the range will be the only element positioned directly opposite an emitter, said detector elements adapted to produce a signal indicating the intensity of a force field in which it is positioned, means responsive to the signals produced by said detector elements for indicating magnitude of movement of the detector elements relative to the emitters, and an insulative coating disposed on the facing surface of one of the substrates.

Claim 34

A transducer as in Claim 33 wherein said force field emitters are charged electrical elements, and wherein said detector elements are field-effect transistors.

Claim 35

A transducer as in Claim 33 wherein said force field emitters are permanent magnets, and wherein said detector elements are split drain magnetic field-effect transducers.

Claim 36

A linear displacement transducer for measuring the movement of an object comprising a base plate, a substrate disposed on the base plate and including sensor means located at a surface area of the substrate for detecting the location of a field producing element at the surface area, an insulative layer disposed over said surface area, an emitter plate disposed in sliding contact with insulative layer, said emitter plate including a field-producing element, and carrying means having a central section on which the emitter plate is mounted and to which the object is coupled, and at least two laterally resilient legs, each extending from an opposite side of the central section in opposite directions from one another, the free ends of the legs being pivotally attached to the base plate so that the central section, and thus the emitter plate and field-producing element, may be moved relative to the substrate when the object is moved.

Claim 37

Apparatus for measuring strain in an object comprising a base plate, a substrate disposed on the base plate and including sensor means located at a surface area of the substrate for detecting the location of a field producing element at the surface area, an insulative layer disposed over said surface area, an emitter plate disposed in sliding contact with insulative layer, said emitter plate including a field-producing element, and attachment means comprising first and second T-shaped elements, each having a long leg and a cross leg disposed perpendicularly to the long leg, each short leg pivotally connecting a respective side of the emitter plate to the base plate so that the long legs extend in the same direction generally parallel to one another for pivotal attachment at their free ends to the object, the strain in the object causing the long legs to move toward or away from one another to thereby cause the emitter plate to move and slide over the substrate.