US2289463A - Circuit maker and breaker - Google Patents

Description

H. A. SCHLOSSER July 14, 1942.

CIRCUIT MAKER AND BREAKER Filed March 31, 1941 Patented Juli, 1942 UNITED STATES PATENT OFFICE Application March 31, 1941, Serial No. 386,162

4 Claims.

This invention relates to circuit makers and breakers, and the present application is a continuation-impart of my prior application, Serial No. 259,671, filed March 3, 1939, entitled Automatic direction switch, now matured into Patent No. 2,241,164, of May 6, 1941.

In the art of electric signaling there are many circuit systems which have associated means for effecting intermittent opening. and closing of a circuit as a function thereof. The present invention has particular utility in this fleld, but is applicable to any system requiring the intermittent make and break of an electrical circuit.

An object of the invention is to provide a circuit maker and breaker of the fluid pressure type, having self-contained means for effecting sustained automatic operation thereof to cause intermittent opening and closing in rapid succession of an electrical circuit with which it is associated.

Another object is to provide, in a fluid pressure circuit maker and breaker, control means biased to" inoperative position and movable therefrom by manual operation, and actuator mechanism that is set in automatic operation by switch means to and from the initial position.

Related objects include the provision of a novelquick-acting actuator means in operativeassociation with the fluid pressure responsive element of a fluid pressure circuit maker and breaker, and a novel structural arrangement of control valve and circuit switch. In the drawing: a

Figure l is a schematic representation of a practical embodiment of the invention.

Figure 2 is substantially a central vertical sectional view through the circuit maker and breaker shown in elevation in Figure 1.

V Figure 3 is a section taken on the line 33 of Figure 2.

Figure 4 is a section similar to Figure 2, but showing a difierent position of certain of the parts, assumed in operation.

In detail, the invention comprises a chamber enclosed by two half-sections of casing 5 and 6 having mating edge flanges connecting by securing elements 1, with a flexible diaphragm 8 clamped therebetween and dividing the chamber into two non-communicating portions. One casing section is provided with a central socket 9 that seats spring means II which bears against the diaphragm under a compression urging it in the direction of the opposite section.

A draw bar I I is secured at its inner end to. the diaphragm center and extends laterally therefrom on the side opposite that against which the spring bears. The bar projects through the adjacent casing wall, which is apertured to permit its free movement therethrough, and at its outer end is pivotally connected to an ear stud 12 on a strut l3 that extends transversely between and connects a pair of parallel throw levers. M. The lower ends of the levers have a knife-edge fulcrum bearing in rigid support members I5 carried by and projecting from the adjacent casing section, and at their upper ends the levers are connected by a transverse top bar i6. Preferably, but not necessarily, the levers l4, strut I3, and top bar iii are of integral construction and occupy a common plane. The assembly of levers, strut, and top bar constitutes, in effect, a unitary throw member which is a lever pivoted at its lower end to a fixed part of the casing assembly, and which is capable of oscillation in a vertical plane under propulsion by the draw bar.

That portion of the I diaphragm chamber through which the draw bar ll operates is at all times open to the atmosphere through the draw bar aperture in the casing wall, so that fluid pressure therein is constant. The chamber at the other side of the diaphragm is, however, subjected to pressure that is variable in accordance with operating movement of valve means under both automatic actuation and remote manual control.

The valve means includes a casting i1 rigidly attached to the casing assembly and extending laterally therefrom centrally of its bottom edge to provide a tubular valve casing having an axial, cylindrical bore l8 entirely there- 'through. At one end the valve casing abuts'the edge flange of the variable pressure chamber, and at its other end is formed with an internally threaded socket to receive the threaded nipple I9 of a pipe coupling 20. The bore 21 of the pipe coupling is reduced relative to" the valve tion of the apparatus parts the inner end of-the valve plug 2'2 seats firmly against the end of the nipple l8 and closes ofl communication between v the bores 18 and 2|, while the variable pressure chamber is in open communication with the atmosphere through a conduit 25 which estab lishes communication between the chamber in terior through the casing section '6 to the bore ll! of the valve casing and a lateral-port 23 leading therefrom to the exterior of the valve casing.

The points at which the conduit 25 and port 26 communicate with the bore 18 are spaced apart axially of the bore a distance sufllcient so that when the valve 22 is at its extreme open position, shown in Figure 4, the port 26 will be fully closed and the pipe bore 2| will be in unobstructed communication with the conduit 25 from the variable pressure chamber. when the valve isfully closed, as shown in Figure 3, a diametrically reduced portion stem registers with the conduit 25 and port 26 for communication therebetween. while'the conduit is cut oil from any communication with the pipe bore 2|. Preferably, the port 23 is controlled by a needle valve 23.

The body of the valve plug 22 is of insulating material except for an annular band 29 of electro-conductive material disposed around its periphery intermediate the ends, preferably adjacent the inner end of the valve. The band 29 retained in their sockets by the positive upward pull exerted by a pair of contraction springs 4| connected at their upper ends to the throw lever top bar 16 and at their lower ends to the later-' ally projecting ends of a cross bar 42 rigidly secured to the lever 31. At its lower end the actuator lever 31 is bifurcated to straddle the valve 21 of the valve provides a valve carried means for electrically 1 bridging a pair of diametrically opposed ball and spring contacts and 3| mounted in the usual manner in bushings of insulating material disposed through the body of the valve casing. The

- contacts are part of an electrical circuit C, in-

dicated generally as also including translating means L and a current source B.

The organization shown in Figure 1 illustrates a practical application of the'invention in which B is the battery, of an automobile, L is a stop light, and the valve stem 23 has a cable connection 32 with a brake pedal 33; a spring connector. 34 being interposed in the cable.- The pipe coupling 2ll\connects with a tubing line 35 to a vacuum tank 36 in which suction is maintained by operation of the motor, not shown. Figures 1 and 3 show the initial, inoperative position of the parts, with the valve 22 closed and retained against its seat by suction in the line 35 and pipe coupling bore 2|.

When the pedal 33 is. advanced to brake applying position apull is exerted on the cable 32 to shift the valve stem and move the valve 22 from its seat to fully open position as shown in Figure 4, uncovering the mouth of the conduit 25 and subjecting the variable pressure chamber to suction by reason of vacuum in the tank 36 and line 35. As the valve moves to open position, the bridging member 29 is brought into registry with the contacts 30 and 3| to close the circuit C and light the lamp L.

Immediately upon the setting up of a vacuurn behind the diaphragm 8, a sudden pull is exerted on the draw bar I I by the corresponding fiexingof the diaphragm into the casing .section 6, and the spring 10 is compressed. The movement' of the drawbar correspondingly rocks the throw levers I4 into the position shown in'Figure 4. Movement ofthe throw-lever means brings into play a snap action lever 31 which operates to return the valve 22 to initial closed position and break the circuit, as will be described. v

The lever 31 constitutes a valve actuator, and comprises a flat bar having at its upper end a guide finger 38 that plays between the outer ends of a pair of parallel supports 39 rigidly secured to the casing section 5 and'extending laterally therefrom. fur-therprovided with knife edge shoulders 43 which pivot in fulcrum sockets in the under The upper end of the bar is stem 23 with suflicient clearance to permit free swing of the lever over and along the valve stem andto provide arm portions 43 adapted to engage a cross pin abutment 44 carried by the valve stem. The lever 31 oscillates in a vertical plane; its extent of outward swing being limited by a stirrup member 45 attached to the casin assembly, and its inward swing being limited by the throw lever strut l3.

It will be noted that the pivot oi the actuator lever 31 is above the pivot point of the throw lever l4 and laterally offset relative thereto outwardly from the casing; also, that motive power is applied to the lever 31 from the springs 4| at a pointabove the fulcrum of the throw lever. In the rocking of the throw-lever assembly, its top bar I6 passes above the fulcrum of the actuator lever in the supports 39, so that, as it passes deadcenter, the pull of the springs rocks the actuator lever 31 with a quick snap action.

In operation, when the valve 22 moves to open position its stem abutment 44 moves correspondingly until it engages the inner face of the lower end portion of the actuator lever 31 which, being held by the stirrup 45 arrests further movement of the valve. Duringopening travel of the valve the circuit will have been first closed and then opened acrossv the contacts 30 and 3|. When the valve reaches fully open position to establish a vacuum behind the diaphragm as explained, the pull of the draw bar I I rocks the throw lever assembly which, in turn, rocks the actuator lever 31 with a quick snap action that kicks the valve stem abutment 44 inwardly and thus returns the valve to initial closed position; during which movement the circuit will once again have been made and broken. The force exerted by the actuator lever is suflicient to overcome the tension of the spring connector 34 in the brake pedal cable, but when the lever comes to rest the pull of the spring, as it contracts, pulls the valve back again to open position, which again opens and closes the circuit. It will be understood that I exerted by the actuator lever 31 in returning the valve to closed position.

As soon as the valve returns to initial closed position, the exhausted variable pressure chamber is opened to the atmosphere through the conduit 25 and port 26, so that pressure at both sides of the diaphragm becomes equal. The equalization of pressure permits expansion of the spring It to push the draw bar outwardly, whereupon the throw lever assembly is rocked to snap the actuator lever 31 back against the stirrup 45 in its initial position, freeing it from the valve stem abutment 44. The valve immediately starts to open, under pull of the spring 34, and in moving to open position it again makes and breaks the of the valve continues rapidly and automatically so long as the brake pedal 33 is held in brake. applying position, and the stop light L is thus caused to flash on and oil by the continuous making and breaking of the circuit. This con-,

dition endures until the brake pedal is released,

whereupon the parts reassume their initial positions, with the valv 22 closed and the circuit broken. The valve is normally retained in closed position against its seat by the urge of suction acting in the line 35 to bias the valve closed position.

It is to be understood that; within th scope of the invention as claimed, the structural details and arrangement of parts herein disclosed may be varied as desired. The illustrated pedal 33' is representative of any means manually operative to accomplish work; the diaphragm is rep-- resentative of any fluid pressure responsive means; the valve 22, chamber assembly. vacuum line and tank may be any means for establishing of the pressure responsive means to effect automatic operation of the valve and switch; and the cable 32 with spring 34 is a remote control connection between the member 33 and the means for establishing fluid pressure differences.

I claim:

1. Electrical circuit control means comprising a member movable in response to difference in a pressure. other than atmospheric whereby to flex said diaphragm, said valve having an operating stem, an actuator leverfulcrumed on the casing structure to oscillate longitudinally oi the valve stem, an operating member secured to said diaphragm for movement therewith as it.

flexes, quick throw means connecting said operating member and lever for oscillation of the lever on movement of the operating member, and cooperative means on said lever and valve stemengageable to shift the valve stem in one direction. during oscillation of the lever, said a valve having an electro-conductive portion, and

fluid pressure at opposite sides thereof, means], biased to a normal position establishing a presj sure balance'at opposite sides of the member and being movable to a limit position establishing a pressure difference between opposite sides of the member whereby to cause movement of the member, a circuit switch connected with said means to open and close as said means is moved, a. manual control member movable to work position, an operating connection between said control member and the pressure establishing means for moving said means to its limit position on movement of the control member to work po: sition, said operating connection including a resilient member, mechanism connected to and operative by movement of the pressure responsive member to engage and restore said pressure establishing means to its normal position against tension imposed by said resilient member, and means operative upon balancing of pressure on the pressure responsive member to release said mechanism to permit said resilient member to again move the pressure establishing means to its limit position.

2- A circuit maker and breaker comprising a diaphragm flexible in accordance with variations in fluid pressure on opposite sides thereof, a

casing enclosing said diaphragm to form nonoommunicating chambers on opposite sides thereof, one chamber being open to the atmosphere, a conduit leading from the other chamber, a valve controlling said conduit and being shiftable to one position opening said conduit to the atmosphere and to another position closing said conduit to the atmosphere and placing said conduit in communication with a source of fluid pressure other than atmospheric thereby permitting the establishment in its chamber of normally separated circuit contacts adapted to be bridged by said conductive portion during movement of the valve.

3. Electrical circuit control means comprising 'a source of fluid pressure, a fluid pressure operated device, valve means controlling communication between said source of fluid pressure and said pressure operated device, acontrol member manually movable to operative and inoperative positions, a mechanical connection including a spring member between said control member 'and said valve means adapted, upon movement of said control member to operative position to open said valve means to actuate said'pressure operated device, a linkage between said pressure operated device and said valve means operative, upon actuation of said pressure operated device, to return said valve to closed position against the opposition of said spring member and to relieve the pressure from said pressure operated device whereupon said spring member causes reopening of said valve means and the opening and closing of said valve means continues so long as said control member remains in operative position, said valve means includin an electrical circuit control operative to make and break an electrical upon each opening and I closing of said valve means.

4. Electrical circuit control means comprising a casing, a flexible diaphragm dividing the interior thereof into two non-communicating chambers, a valve casing on the diaphragm casing and having an axial bore in communication with a fluid pressure line, a valve slidable in said bore to open and close the fluid pressure line, a conduit establishing communication between a chamber at one side of the diaphragm and the valve casing bore, said valve casing having a port opening from its bore to the atmosphere, said valve when in open position placing the conduit in communication with the fluid pressure line through the bore and when in closed. position placing the conduit in communication with said port through the bore, a. stern for op-- erating said valve and projecting beyond an end of the valve casing, a support on the diaphragm casing, an actuator lever pivoted at one end on said'support, the other end of said lever having a portion loosely straddling the valve stem, an abutment on' the stem engageable by said lever portion to move the valve and stem with the lever as it moves in, one direction, a draw bar secured to the diaphragm, a snap throw lever pivoted at one end on the casing, said draw bar having pivotal connection with the snap lever intermediate its ends, and spring means connecting the free end portion of the snap' lever with an intermediate portion of the actuator lever, said valve including means for making and breaking a circuit as the valve is moved.

HENRY A. SCI-ILOSSER.

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