US3502835A - Momentary electric switch for gas range burner - Google Patents

Description

March 24, 1970 K; BATCHELLER I 3,502,835

Q ITCH FOR GAS BANG B Filed NOV. 16, 1967 IN E TOR.

KENT J. BATC LLER ATTORNEYS United States Patent 3,502,835 MOMENTARY ELECTRIC SWITCH FOR GAS RANGE BURNER Kent J. Batcheller, Westwood, Mass., assignor to Joseph Pollak Corporation, Dorchester, Mass., a corporation of Massachusetts 1 Filed Nov. 16, 1967, Ser. No. 683,588 Int. Cl. H01h 3/32, 3/42 US. Cl. 200-454 1 Claim ABSTRACT OF THE DISCLOSURE This invention relates to an electric switch which closes momentarily when a shaft associated with it is turned through a considerable angle in one direction but does not close when the shaft is turned back to its starting position. The switch is designed particularly for use in connection with a valve by which gas is turned on and off for a range burner. The ordinary practice for gas burners which are subject to intermittent use is to provide a small pilot flame which ignites the gas flow when it is turned on. Pilot lights steadily consume gas for no other purpose and are also apt to go out as for example when there is an interruption in the supply of gas from the mains. Electric devices are available which are capable of producing a series of rapid sparks between electrodes when a circuit including the electrodes is closed. The sparking device can be made to provide a brief burst of sparks or a longer series of sparks, say, for a substantial fraction of a second, in response to a momentary closing of the circuit containing the spark-producing device. For this purpose a switch is provided which closes momentarily when a shaft is turned through part of a revolution in a direction to open a gas valve, but does not close at all when the shaft is turned back to its starting position.

For a more complete understanding of the invention reference may be had to be following description thereof and to the drawing, of which:

FIGURE 1 is a perspective view of a gas valve with an electric switch connected to it for operation thereby; and

FIGURES 25 are elevational views of the switch, showing the parts in various positions of operation.

An electric switch embodying the invention is shown in connection with a valve of the stopcock type such as is often used on gas ranges to control the flow of gas to the burners. The valve is operated by a stem or shaft 12 on which a suitable handle 14 can be mounted. The shaft 12 extends axially through a disk 16 to turn the disk on its axis when the shaft 12 is turned.

The disk is housed in a shallow casing 18 having side walls 20, 22, 24, 26 of uniform height. The casing has a square exterior shape as shown on the drawing. The walls 20 and 24 are widened at their mid points to receive screws 27, 28 by which a cover plate 30 is removably attached to the casing. As indicated in FIGURE 1, this cover plate may be transparent.

The disk 16, as shown, is approximately circular in shape and is of insulating material, at least at its periphery. Its thickness is silghtly less than the height of the casing walls. Its periphery includes a notch forming a ice radial shoulder 32 and a flat 34 about a quadrant away from the shoulder.

Within the casing are two conductors 40, 42 at least one of which is preferably a flexible strip of Phosphor bronze for resilience and current-carrying efficiency. As shown, both conductors are strips of metal bent to shape and arranged edgewise to the bottom of the casing, the width of the strips being slightly less than the height of the casing walls. The wall 26 of the casing is interrupted at 44 and 46 for the admission of connecting wires, but it also has an interior extension 48 with recesses 50 and 52 in which are fitted end portions 54 and 56 of the conductors 40 and 42 respectively. The end portion 54 of the conductor 40 is curved to fit into the recess 50 but has a straight terminal extending across the gap 44 so that when a connecting wire 60 is thrust through the gap 44 into the casing it flexes the end portion 54 of the conductor 40 and is gripped thereby. In like manner the curved end portion 56 of the conductor 42 has a terminal projecting across the gap 46 to be engaged by a connecting wire 62 when the wire is thrust through the gap 46. The free end portion 64 of the conductor 40 is located in the path of the free end portion contact area 66 of the conductor 42. Near the end portion 66 of the conductor 42 is a shoulder 68 which may be formed by reversely bending the conductor as shown. Between the shoulder 68 and the fixed end portion 56 of this conductor is an intermediate portion 70 which is in the form of an open loop so formed as to cause the portion of the conductor 42 adjacent to the shoulder 68 to press resiliently against the periphery of the disk 16 so that when the disk 16 is turned clockwise to an angular position a little beyond that shown in FIGURE 2, the shoulder 68 snaps into position to be engaged by the shoulder 32 of the disk when the latter is turned in the counterclockwise direction which, in this case, is the direction for turning on the gas, i.e., opening thegas valve. By means not shown on the drawing, the counterclockwise rotation is limited to the position shown in FIGURE 5, this being slightly more than a half-turn from the starting or off position.

When the disk 16 is turned counterclockwise from the off position, the shoulders 32 and 68 become engaged. Further movement of the disk in that direction flexes the conductor so that its end portion 66 moves to the left into rubbing contact with the end portion 64 of the conductor 40. If, as shown, the disk is approximately circular in shape, the flat 34 is arranged to permit free flexing of the conductor 42 when the shoulder 32 pushes the end portion 66 of the conductor into contact with the conductor 40 to close the switch momentarily. The end portions 64 and 66 are so arranged that as the rotation of the disk continues, the contact area 66 is cammed outward from the disk so that the shoulder 68 rides over the shoulder 32, breaking the contact between the conductors 40 and 42 as indicated in FIGURE 4. The conductor 42 then snaps back to the position shown in FIGURE 5 but still presses against the periphery of the disk 16.

When the disk is thereafter turned clockwise to turn off the gas, i.e., close the gas valve, the conductor 42 is not flexed toward the left and no closing of the switch results.

I claim:

1. An electric switch comprising a housing, a disk rotatably mounted in said housing, said disk having a peripheral notch forming a radial shoulder, first and second conductors in said housing each consisting of a strip of resilient metal bent to shape, each said conductor having one end secured to said housing and the other eiid free, the first said conductor having a contact area at its free end, a reverse bend near said free end forming a shoulder normally bearing on the shoulder on the disk, and a loop connecting said reversely bent portion with the secured end whereby said loop is flexed when the disk is rotated in the direction to advance said shoulders, the free end portion of said second conductor being located in the path of the contact area of the first conductor, camming means for disengagement of the shoulder on the first conductor and the shoulder on the disk, said camming means pushing said contact area of the first conductor outward from said free end of the second conductor, said loop unfiexing and retracting said contact area of the first conductor away from said free end of the second conductor when the shoulder on the first conductor is disengaged from the shoulder on the disk by said camming means.

References Cited UNITED STATES PATENTS 2,037,148 4/1936 Reeves 200-460 XR 2,431,197 11/1947, Platt et a1 20068 XR 3,120,589. 2/1964 Westberg ZOO-453.13

ROBERT S. MACON, Primary Examiner R. A. VANDERHYE, Assistant Examiner US. Cl. X.R.

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