Vacuum switch cam operating mechanism with contact loading compression spring

Claim 2

In an electric circuit breaker having at least three interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; opErating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into and out of engagement with their associated stationary contacts; an elongated cam bar supported for reciprocal movement in a direction transverse to the direction in which said movable contacts are movable; a plurality of identical cam slots formed in said cam bar, one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam track portion inclined at an oblique angle to the direction of cam bar reciprocation, each cam slot also including a cam track portion at each end of said inclined portion, said cam slots each operatively receiving a cam follower; a pivoted yoke for each cam follower and operatively connected to each cam follower for guiding the lower end of said contact in such a manner that in the closing movement said movable contacts move in an arcuate path of travel that terminates on a line that includes the axes of the contacts when said contacts are in closed position to thereby provide a wiping engagement between the contact faces of said contacts; and, a contact loading compression spring for each of said contacts, said loading compression spring being supported in position to provide for predetermined high pressure engagement between the movable contact and an associated stationary contact irrespective of the amount of over travel of an associated cam follower, whereby movement of said cam bar in one direction will effect simultaneous movement of all of said movable contacts in the same direction into engagement with their associated stationary contacts and upon movement of said cam bar in the opposite direction all of said movable contacts will move simultaneously in the same direction to open positions.

Claim 3

An electric circuit breaker in accordance with claim 1 wherein each of said cam followers include a roller disposed in an associated one of said cam slots and said cam bar has a plurality of guide grooves therein elongated in the direction of reciprocation of said cam bar, and wherein said circuit breaker also has means including guide grooves and guide rollers disposed in said guide grooves for guiding said cam bar in its direction of reciprocation and preventing movement thereof in all directions transverse to its direction of reciprocation.

Claim 4

In an electric circuit breaker having at least three vacuum interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; operating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into and out of engagement with their associated stationary contacts, said operating means including contact loading compression spring means for transmitting contact closing motion of each of said cam followers to each of said movable contacts, and means for deflecting each of said contact loading compression spring means to a predetermined loading and for providing a positive connection between said associated cam follower and said associated movable contact when said cam follower is moved in contact opening direction and each being adjustable to vary said predetermined loading; an elongated cam bar supported for reciprocal movement in a direction transverse to the direction in which said movable contacts are movable; a plurality of identical cam slots formed in said cam bar one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam track portion inclined at an oblique angle to the direction of cam bar reciprocation, each cam slot also including a cam track portion At each end of said inclined portion, said cam slots each operatively receiving a cam follower; a pivoted bell crank lever having an arm pivotally connected to said reciprocable cam bar; preloaded contact opening spring means engaging an arm of said bell crank lever and further loaded when said cam bar is reciprocated in a direction to close said contacts of said plurality of vacuum interrupters; and, latch means adapted to releasably engage an arm of said bell crank lever for holding said bell crank lever and said cam bar in a position wherein said contacts of said plurality of interrupters are closed, whereby the forces of said plurality of contact loading compression spring means and of said contact opening spring means are additive to open said plurality of vacuum interrupters.

Claim 5

In an electric circuit breaker having at least three vacuum interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; operating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into and out of engagement with their associated stationary contacts, said operating means including contact loading compression spring means for transmitting contact closing motion of each of said cam followers to each of said movable contacts, and means for deflecting each of said contact loading compression spring means to a predetermined loading and for providing a positive connection between said associated cam follower and said associated movable contact when said cam follower is moved in contact opening direction and each being adjustable to vary said predetermined loading; an elongated cam bar supported for reciprocal movement in a direction transverse to the direction in which said movable contacts are movable; a plurality of identical cam slots formed in said cam bar one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam track portion inclined at an oblique angle to the direction of cam bar reciprocation, each cam slot also including a cam track portion At each end of said inclined portion, said cam slots each operatively receiving a cam follower; a pivoted bell crank lever having an arm pivotally connected to said reciprocable cam bar; preloaded contact opening spring means engaging an arm of said bell crank lever and further loaded when said cam bar is reciprocated in a direction to close said contacts of said plurality of vacuum interrupters; and, latch means adapted to releasably engage an arm of said bell crank lever for holding said bell crank lever and said cam bar in a position wherein said contacts of said plurality of interrupters are closed, whereby the forces of said plurality of contact loading compression spring means and of said contact opening spring means are additive to open said plurality of vacuum interrupters.

Claim 6

An electric circuit breaker in accordance with claim 3 and including a trip solenoid provided with an armature movable when said solenoid is energized from a released position wherein said latch means can latch said bell crank lever to a trip position wherein said solenoid trips said latch means to free said bell crank lever, said armature having a portion accessible from the exterior of said trip solenoid, a pivoted switch operating handle engaging said accessible portion of said armature and being adapted to move said armature from said released position to said trip position, and spring means engaging said accessible portion of said armature for normally holding said armature in said released position and thereby preventing inadvertent opening of said vacuum switch contacts when said operating handle is engaged with a hot stick.

Claim 7

In an electric circuit breaker, in combination; a supporting base; a plurality of vacuum interrupters mounted in spaced relation on said base in a plane transverse to said base and each having a stationary contact, movable contact, and means including a cam follower for operating said movable contact into and out of engagement with said stationary contact; elongated reciprocable cam bar means having a plurality of cam slots therein each of which has a cam track portion oblique to the direction of cam reciprocation receiving one of said cam followers for simultaneously actuating said movable contact operating means of said plurality of vacuum interrupters; means affixed to said supporting base for guiding and supporting said cam bar for reciprocation in said plane transverse to said base; a mounting plate, said cam bar guiding means supporting said mounting plate in said plane transverse to said base; bell crank lever means pivoted on said mounting plate and having one arm operatively connected to said reciprocable cam bar; switch opening spring means affixed at one end to an arm of said bell crank lever means and at the other end to said mounting plate and being further loaded when said cam bar is reciprocated in the switch closing direction; latch means pivotally supported on said mounting plate for latching said bell crank lever when said cam bar is in switch closing position; and trip solenoid means affixed to said mounting plate for releasing said latch means to free said bell crank lever means when said trip solenoid is energized.

Claim 8

In an electric circuit breaker, in combination; a supporting base; a plurality of vacuum interrupters mounted in spaced relation on said base in a plane transverse to said base and each having a stationary contact, movable contact, and means including a cam follower for operating said movable contact into and out of engagement with said stationary contact; elongated reciprocable cam bar means having a plurality of cam slots therein each of which has a cam track portion oblique to the direction of cam reciprocation receiving one of said cam followers for simultaneously actuating said movable contact operating means of said plurality of vacuum interrupters; means affixed to said supporting base for guiding and supporting said cam bar for reciprocation in said plane transverse to said base; a mounting plate, said cam bar guiding means supporting said mounting plate in said plane transverse to said base; bell crank lever means pivoted on said mounting plate and having one arm operatively connected to said reciprocable cam bar; switch opening spring means affixed at one end to an arm of said bell crank lever means and at the other end to said mounting plate and being further loaded when said cam bar is reciprocated in the switch closing direction; latch means pivotally supported on said mounting plate for latching said bell crank lever when said cam bar is in switch closing position; and trip solenoid means affixed to said mounting plate for releasing said latch means to free said bell crank lever means when said trip solenoid is energized.

Claim 9

An electric circuit breaker in accordance with claim 5 and including a closing solenoid supported on said mounting plate and having a plunger operatively connected to an arm of said bell crank lever means for actuating said cam bar to switch closing position when said closing solenoid is energized.

Claim 10

An electric circuit breaker in accordance with claim 6 wherein said trip solenoid is provided with an armature movable when said trip solenoid is energized from a released position wherein said latch means can latch said bell crank lever means to a trip position wherein said trip solenoid armature trips said latch means to free said bell crank lever means, said trip solenoid armature having an accessible portion; a switch operating handle pivotally supported on saId mounting plate and being adapted to move said trip solenoid armature from said released position to said trip position; and, spring means engaging said accessible portion of said trip solenoid armature for normally holding said armature in said released position, thereby preventing inadvertent opening of said vacuum interrupter contacts when said operating handle is engaged with a hot stick.

Claim 11

An electric circuit breaker in accordance with claim 5 wherein said cam bar guiding and supporting means includes a plurality of aligned pairs of cam guide legs projecting from the side of said supporting base opposite that on which said vacuum interrupters are mounted and with the legs of each said pair being spaced apart and disposed on opposite sides of a plane transverse to said base and of said cam bar and affixed adjacent their ends to said mounting plate.

Claim 12

An electric circuit breaker in accordance with claim 8 wherein said cam bar has a plurality of cam grooves therein elongated in the direction of cam bar reciprocation each of which is adjacent one of said pairs of cam guide legs, and said cam bar guiding and supporting means includes said cam grooves, a roller in each of said cam grooves, and a roller support member extending through each said pair of cam guide legs and revolvably supporting one of said rollers with the corresponding cam groove.

Claim 13

An electric circuit breaker in accordance with claim 9 wherein each said movable contact operating means includes yoke means pivotally mounted at one end on one of said roller support members and operatively connected at the other end to one of said cam followers for guiding said movable contact in a manner to insure substantial face-to-face engagement between contacts when in closed positions.

Claim 14

An electric circuit breaker in accordance with claim 10 wherein each said movable contact operating means also includes an elongated, longitudinally reciprocable, insulated contact operating rod operatively connected at one end to the associated movable contact and precompressed contact loading compression spring means for transmitting switch closing cam follower motion to the other end of said contact operating rod.

Claim 15

In an electric circuit breaker having at least three interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; operating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into and out of engagement with their associated stationary contacts; an elongated cam bar supported for reciprocal movement in a direction transverse to the direction in which said movable contacts are movable; a plurality of identical cam slots formed in said cam bar one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam track portion inclined at a oblique angle to the direction of cam bar reciprocation, each slot also including a cam track portion at each end of said inclined portion, said cam slots each operatively receiving a cam follower; an elongated, longitudinally reciprocable, insulated contact operating rod for each axially movable contact, said operating rods being operatively connected to an adjacent end of an associated movable contact; precompressed contact loading compression spring means for transmitting switch closing cam follower motion to the other end of each of said contact rods; a U-shaped stirrup bracketing each of said cam followers and an associated contact operating rod, each of said U-shaped stirrups having the legs thereof operatively coupled to an associated cam follower, said contact loading compression spring means being adapted to react at its opposite ends against the cross piece of said U-shaped stirrup and against said other end of said associated contact operating rod; adjustable bolt means affixed to said other end of each of said contact operating rods for precompressing said contact loading compression spring means against the cross piece of said U-shaped stirrup and for varying the stroke of said contact operating rod resulting from switch closing motion of said cam follower; and, a pivoted member for each of said cam followers operatively connected to an adjacent end of an associated insulated contact operating rod for guiding the movement of the adjacent lower end of an associated movable contact in an arcuate path of travel that terminates on a line that includes the axes of said contacts when said contacts are in closed position to thereby provide a wiping engagement between the contact faces of said contacts.

Claim 16

In an electric circuit breaker having at least three interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; operating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into and out of engagement with their associated stationary contacts; an elongated cam bar supported for reciprocal movement in a direction transverse to the direction in which said movable contacts are movable; a plurality of identical cam slots formed in said cam bar one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam track portion inclined at a oblique angle to the direction of cam bar reciprocation, each slot also including a cam track portion at each end of said inclined portion, said cam slots each operatively receiving a cam follower; an elongated, longitudinally reciprocable, insulated contact operating rod for each axially movable contact, said operating rods being operatively connected to an adjacent end of an associated movable contact; precompressed contact loading compression spring means for transmitting switch closing cam follower motion to the other end of each of said contact rods; a U-shaped stirrup bracketing each of said cam followers and an associated contact operating rod, each of said U-shaped stirrups having the legs thereof operatively coupled to an associated cam follower, said contact loading compression spring means being adapted to react at its opposite ends against the cross piece of said U-shaped stirrup and against said other end of said associated contact operating rod; adjustable bolt means affixed to said other end of each of said contact operating rods for precompressing said contact loading compression spring means against the cross piece of said U-shaped stirrup and for varying the stroke of said contact operating rod resulting from switch closing motion of said cam follower; and, a pivoted member for each of said cam followers operatively connected to an adjacent end of an associated insulated contact operating rod for guiding the movement of the adjacent lower end of an associated movable contact in an arcuate path of travel that terminates on a line that includes the axes of said contacts when said contacts are in closed position to thereby provide a wiping engagement between the contact faces of said contacts.

Claim 17

In an electric circuit breaker having at least three vacuum interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; operating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into an out of engagement with their associated stationary contacts; an elongated cam bar supported for reciprocal movement in a direction transverse to the direction in which said movable contacts are movable; a plurality of identical cam slots formed in said cam bar one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam truck portion inclined at an oblique angle to the direction of cam bar reciprocation, each cam slot also including a cam track portion at each end of said inclined portion, said cam slots each operatively receiving a cam follower; an elongated, longitudinally reciprocable, insulated contact operating rod for each axially movable contact, said operating rods being operatively connected to an adjacent end of an associated movable contact; precompressed contact loading compression spring means for transmitting switch closing cam follower motion to the other end of each of said contact rods; a U-shaped stirrup bracketing each of said cam followers and said other end of an associated contact operating rod; individual bolt means extending through the legs of each of said stirrups and through said associated cam follower for coupling said stirrups to said cam followers, wherein said contact loading compression spring means react at one end against the cross piece of associated stirrups and at the opposite end against said other end of an associated contact operating rod; individual bolt means affixed to said other end of each of said contact operating rods and extending through an associated contact loading compression spring means and through a clearance aperture in the cross piece of an associated stirrup for adjusting the position of said operating rod relative to the cross piece of its associated U-shaped stirrup to thereby provide means for varying the preloading of said contact loading compression spring means and the stroke of said contact operating rod as desired; and, a pivoted member for each of said insulated contact operating rod operatively connected to an adjacent end of an associated cam follower for guiding the movement of the adjacent lower end of an associated movable contact in an accurate path of travel that terminates on a line that includes the axes of said contacts when said contacts are in closed position to thereby provide a wiping engagement between the contact faces of said contacts.

Claim 18

In an electric circuit breaker having at least three vacuum interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; operating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into an out of engagement with their associated stationary contacts; an elongated cam bar supported for reciprocal movement in a direction transverse to the direction in which said movable contacts are movable; a plurality of identical cam slots formed in said cam bar one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam truck portion inclined at an oblique angle to the direction of cam bar reciprocation, each cam slot also including a cam track portion at each end of said inclined portion, said cam slots each operatively receiving a cam follower; an elongated, longitudinally reciprocable, insulated contact operating rod for each axially movable contact, said operating rods being operatively connected to an adjacent end of an associated movable contact; precompressed contact loading compression spring means for transmitting switch closing cam follower motion to the other end of each of said contact rods; a U-shaped stirrup bracketing each of said cam followers and said other end of an associated contact operating rod; individual bolt means extending through the legs of each of said stirrups and through said associated cam follower for coupling said stirrups to said cam followers, wherein said contact loading compression spring means react at one end against the cross piece of associated stirrups and at the opposite end against said other end of an associated contact operating rod; individual bolt means affixed to said other end of each of said contact operating rods and extending through an associated contact loading compression spring means and through a clearance aperture in the cross piece of an associated stirrup for adjusting the position of said operating rod relative to the cross piece of its associated U-shaped stirrup to thereby provide means for varying the preloading of said contact loading compression spring means and the stroke of said contact operating rod as desired; and, a pivoted member for each of said insulated contact operating rod operatively connected to an adjacent end of an associated cam follower for guiding the movement of the adjacent lower end of an associated movable contact in an accurate path of travel that terminates on a line that includes the axes of said contacts when said contacts are in closed position to thereby provide a wiping engagement between the contact faces of said contacts.

Claim 19

In an electric circuit breaker, in combination; a supporting base; a plurality of vacuum interrupters mounted in spaced relation on said base in a plane transverse to said base and each having a stationary contact, a mOvable contact, and means including a cam follower for operating said movable contact into and out of engagement with said stationary contact; elongated reciprocable cam bar means having a plurality of cam slots therein each of which has a cam track portion oblique to the direction of cam reciprocation receiving one of said cam followers for simultaneously actuating said movable contact operating means of said plurality of vacuum interrupters; means affixed to said supporting base for guiding and supporting said cam bar for reciprocation in said plane transverse to said base; a mounting plate, said cam bar guiding means supporting said mounting plate in said plane transverse to said base; bell crank lever means pivoted on said mounting plate and having one arm operatively connected to said reciprocable cam bar; switch opening spring means affixed at one end to an arm of said bell crank lever means and at the other end to said mounting plate and being further loaded when said cam bar is reciprocated in the switch closing direction; latch means pivotally supported on said mounting plate for latching said bell crank lever when said cam bar is in switch closing position; trip solenoid means affixed to said mounting plate for releasing said latch means to free said bell crank lever means when said trip solenoid is energized, said trip solenoid being provided with an armature movable when said trip solenoid is energized from a released position wherein said latch means can latch said bell crank lever means to a trip position wherein said trip solenoid armature trips said latch means to free said bell crank lever means, said trip solenoid armature having an accessible portion; a switch operating handle pivotally supported on said mounting plate and being adapted to move said trip solenoid armature from said released position to said trip position, said switch operating handle having a lever arm operatively connected to said cam bar, wherein manual operation of said handle in one direction reciprocates said cam bar to switch closing position and operation thereof in the opposite direction actuates said trip solenoid armature to said trip position to release said latch means; spring means engaging said accessible portion of said trip solenoid armature for normally holding said armature in said released position, thereby preventing inadvertent opening of said vacuum interrupter contacts when said operating handle is engaged with a hot stick; and, a closing solenoid supported on said mounting plate and having a plunger operatively connected to an arm of said bell crank lever means for actuating said cam bar to switch closing position when said closing solenoid is energized.

Claim 20

In an electric circuit breaker, in combination; a supporting base; a plurality of vacuum interrupters mounted in spaced relation on said base in a plane transverse to said base and each having a stationary contact, a mOvable contact, and means including a cam follower for operating said movable contact into and out of engagement with said stationary contact; elongated reciprocable cam bar means having a plurality of cam slots therein each of which has a cam track portion oblique to the direction of cam reciprocation receiving one of said cam followers for simultaneously actuating said movable contact operating means of said plurality of vacuum interrupters; means affixed to said supporting base for guiding and supporting said cam bar for reciprocation in said plane transverse to said base; a mounting plate, said cam bar guiding means supporting said mounting plate in said plane transverse to said base; bell crank lever means pivoted on said mounting plate and having one arm operatively connected to said reciprocable cam bar; switch opening spring means affixed at one end to an arm of said bell crank lever means and at the other end to said mounting plate and being further loaded when said cam bar is reciprocated in the switch closing direction; latch means pivotally supported on said mounting plate for latching said bell crank lever when said cam bar is in switch closing position; trip solenoid means affixed to said mounting plate for releasing said latch means to free said bell crank lever means when said trip solenoid is energized, said trip solenoid being provided with an armature movable when said trip solenoid is energized from a released position wherein said latch means can latch said bell crank lever means to a trip position wherein said trip solenoid armature trips said latch means to free said bell crank lever means, said trip solenoid armature having an accessible portion; a switch operating handle pivotally supported on said mounting plate and being adapted to move said trip solenoid armature from said released position to said trip position, said switch operating handle having a lever arm operatively connected to said cam bar, wherein manual operation of said handle in one direction reciprocates said cam bar to switch closing position and operation thereof in the opposite direction actuates said trip solenoid armature to said trip position to release said latch means; spring means engaging said accessible portion of said trip solenoid armature for normally holding said armature in said released position, thereby preventing inadvertent opening of said vacuum interrupter contacts when said operating handle is engaged with a hot stick; and, a closing solenoid supported on said mounting plate and having a plunger operatively connected to an arm of said bell crank lever means for actuating said cam bar to switch closing position when said closing solenoid is energized.

Claim 21

In an electric circuit breaker, in combination; a supporting base; a plurality of vacuum interrupters mounted in spaced relation on said base in a plane transverse to said base and each having a stationary contact, a movable contact, and means including a cam follower for operating said movable contact into and out of engagement with said stationary contact, each said movable contact operating means includes yoke means pivotally mounted at one end on one of said roller support members and operatively connected at the other end to one of said cam followers for guiding said movable contact in essentially straight line axial motion as it is actuated between open and closed positions, each said movable contact operating means also includes an elongated, longitudinally reciprocable, insulated contact operating rod operatively connected at one end to the associated movable contact and precompressed contact loading compression spring means for transmitting switch closing cam follower motion to the other end of said contact operating rod; each said movable contact operating means also includes a U-shaped stirrup bracketing said contact loading compression spring means and having the legs thereof operatively connected to said cam follower, and wherein Said contact loading spring means react at one end against the cross piece of said U-shaped stirrup and at the opposite end against said other end of said contact operating rod; elongated reciprocable cam bar means having a plurality of cam slots therein each of which has a cam track portion oblique to the direction of cam reciprocation receiving one of said cam followers for simultaneously actuating said movable contact operating means of said plurality of vacuum interrupters; means affixed to said supporting base for guiding and supporting said cam for reciprocation in the plane transverse to said base; said cam bar guiding and supporting means includes a plurality of aligned pairs of cam guide legs projecting from the side of said supporting base opposite that on which said vacuum interrupters are mounted and with the legs of each said pair being spaced apart and disposed on opposite sides of the plane transverse to said base and of said cam bar and affixed adajcent their ends to said mounting plate; said cam bar has a plurality of cam grooves therein elongated in the direction of cam bar reciprocation each of which is adjacent one of said pairs of cam guide legs, said cam bar guiding and supporting means includes said cam grooves, a roller in each of said cam grooves, and a roller support member extending through each said pair of cam guide legs and revolvably supporting one of said rollers within the corresponding cam groove; a mounting plate, said cam bar guiding means supporting said mounting plate in the plate transverse to said base; bell crank lever means pivoted on said mounting plate and having one arm operatively connected to said reciprocable cam bar; switch opening spring means affixed at one end to an arm of said bell crank lever means and at the other end to said mounting plate and being further loaded when said cam bar is reciprocated in the switch closing direction; latch means pivotally supported on said mounting plate for latching said bell crank lever when said cam bar is in switch closing position; and, a trip solenoid affixed to said mounting plate for releasing said latch means to free said bell crank lever means when said trip solenoid is energized.

Claim 22

In an electric circuit breaker, in combination; a supporting base; a plurality of vacuum interrupters mounted in spaced relation on said base in a plane transverse to said base and each having a stationary contact, a movable contact, and means including a cam follower for operating said movable contact into and out of engagement with said stationary contact, each said movable contact operating means includes yoke means pivotally mounted at one end on one of said roller support members and operatively connected at the other end to one of said cam followers for guiding said movable contact in essentially straight line axial motion as it is actuated between open and closed positions, each said movable contact operating means also includes an elongated, longitudinally reciprocable, insulated contact operating rod operatively connected at one end to the associated movable contact and precompressed contact loading compression spring means for transmitting switch closing cam follower motion to the other end of said contact operating rod; each said movable contact operating means also includes a U-shaped stirrup bracketing said contact loading compression spring means and having the legs thereof operatively connected to said cam follower, and wherein Said contact loading spring means react at one end against the cross piece of said U-shaped stirrup and at the opposite end against said other end of said contact operating rod; elongated reciprocable cam bar means having a plurality of cam slots therein each of which has a cam track portion oblique to the direction of cam reciprocation receiving one of said cam followers for simultaneously actuating said movable contact operating means of said plurality of vacuum interrupters; means affixed to said supporting base for guiding and supporting said cam for reciprocation in the plane transverse to said base; said cam bar guiding and supporting means includes a plurality of aligned pairs of cam guide legs projecting from the side of said supporting base opposite that on which said vacuum interrupters are mounted and with the legs of each said pair being spaced apart and disposed on opposite sides of the plane transverse to said base and of said cam bar and affixed adajcent their ends to said mounting plate; said cam bar has a plurality of cam grooves therein elongated in the direction of cam bar reciprocation each of which is adjacent one of said pairs of cam guide legs, said cam bar guiding and supporting means includes said cam grooves, a roller in each of said cam grooves, and a roller support member extending through each said pair of cam guide legs and revolvably supporting one of said rollers within the corresponding cam groove; a mounting plate, said cam bar guiding means supporting said mounting plate in the plate transverse to said base; bell crank lever means pivoted on said mounting plate and having one arm operatively connected to said reciprocable cam bar; switch opening spring means affixed at one end to an arm of said bell crank lever means and at the other end to said mounting plate and being further loaded when said cam bar is reciprocated in the switch closing direction; latch means pivotally supported on said mounting plate for latching said bell crank lever when said cam bar is in switch closing position; and, a trip solenoid affixed to said mounting plate for releasing said latch means to free said bell crank lever means when said trip solenoid is energized.

Claim 23

An electric circuit breaker in accordance with claim 15 wherein each said movable contact operating means includes bolt means affixed to said other end of said contact operating rod and extending through a clearance aperture in said cross piece of said stirrup for adjusting the deflection of said contact loading spring means and the stroke of said contact operating rod resulting from contact closing motion of said cam follower.

Claim 24

An electric circuit breaker in accordance with claim 16 wherein each said cam slot in said cam bar also has cam track portions at each end of said oblique cam track portion extending parallel to the direction of reciprocation of said cam bar.

Claim 25

In an electric circuit breaker having at least three interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; operating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into and out of engagement with their associated stationary contacts, said operating means includes contact loading compression spring means for transmitting contact closing motion of each of said cam followers to each of movable contact; means for deflecting each of said contact loading compression spring means to a predetermined loading and for providing a positive connection between said associated cam follower and said associated movable contact when said cam follower is moved in a contact opening direction and each being adjustable to vary said predetermined loading; said means for deflecting said contact loading compression spring means is adjustable when said pair of contacts are open to vary the predetermined loading of said contact loading compression spring means and thus change the stroke through which said contact operating means is actuated by said cam follower in a manner that the closing of said pairs of contacts of said plurality of vacuum interrupters can be synchronized at a single point in each of said movable contact operating means; each said movable contact operating means includes an elongated, insulated, axially reciprocable contact operating rod operatively connected at one end to said movable contact, a U-shaped stirrup embracing said contact loading compression spring means and the other end of said operating rod and said cam follower and having the legs of said U-shaped stirrup coupled to said cam follower, and wherein said contact loading compression spring means reacts at one end against the cross piece of said U-shaped stirrup and at its opposite end against said other end of said operating rod; an elongated cam bar supported for reciprocable movement in a direction transverse to the direction in which said movable contacts are movable; and, a plurality of identical cam slots formed in said cam bar one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam track portion inclined at an oblique angle to the direction of cam bar reciprocation, each cam slot also including a cam track portion at each end of said inclined portion, said cam slots each operatively receiving a cam follower.

Claim 26

In an electric circuit breaker having at least three interrupters in parallel vertical array, said interrupters each having a pair of separable contacts one of which is stationary and the other of which is axially movable into and out of engagement with said stationary contact; operating means including a cam follower operably connected to each of said axially movable contacts for actuating all of said contacts simultaneously in the same direction into and out of engagement with their associated stationary contacts, said operating means includes contact loading compression spring means for transmitting contact closing motion of each of said cam followers to each of movable contact; means for deflecting each of said contact loading compression spring means to a predetermined loading and for providing a positive connection between said associated cam follower and said associated movable contact when said cam follower is moved in a contact opening direction and each being adjustable to vary said predetermined loading; said means for deflecting said contact loading compression spring means is adjustable when said pair of contacts are open to vary the predetermined loading of said contact loading compression spring means and thus change the stroke through which said contact operating means is actuated by said cam follower in a manner that the closing of said pairs of contacts of said plurality of vacuum interrupters can be synchronized at a single point in each of said movable contact operating means; each said movable contact operating means includes an elongated, insulated, axially reciprocable contact operating rod operatively connected at one end to said movable contact, a U-shaped stirrup embracing said contact loading compression spring means and the other end of said operating rod and said cam follower and having the legs of said U-shaped stirrup coupled to said cam follower, and wherein said contact loading compression spring means reacts at one end against the cross piece of said U-shaped stirrup and at its opposite end against said other end of said operating rod; an elongated cam bar supported for reciprocable movement in a direction transverse to the direction in which said movable contacts are movable; and, a plurality of identical cam slots formed in said cam bar one for each movable contact, said cam slots being disposed along a common axis, said cam slots having identical configurations including a cam track portion inclined at an oblique angle to the direction of cam bar reciprocation, each cam slot also including a cam track portion at each end of said inclined portion, said cam slots each operatively receiving a cam follower.

Claim 27

An electric circuit breaker in accordance with claim 18 and including bolt means affixed at one end to said contact operating rod and extending through said contact loading compression spring means and also through a clearance hole in said cross piece of said U-shaped stirrup for deflecting said contact loading springs to a predetermined loading and for providing a positive connection between said cam follower and said contact operating rod when said cam follower is actuated in a contact opening direction and permitting relative movement therebetween when said cam follower is actuated in a contact closing direction, said bolt means being adjustable to vary the deflection of said contact loading springs and the contact closing stroke of said contact operating rod.

Claim 28

An electric circuit breaker in accordance with claim 19 wherein each said movable contact operating means includes pivoted yoke means operatively connected to said cam follower for guiding said other end of said contact operating rod in substantially straight line motion axially of said movable contact as said cam follower is actuated by said cam bar.