US2496118A - Electric switch - Google Patents

Description

ELECTRIC SWITCH Filed May 2l, 1947 Mil-MVM Patented Jan. 31, A195@ William Earl Brown, Anderson, 4General Motors Corporation, corporation of `Delaware Ind., assignor to Detroit, Michl., la

Application May`21, 1947, 'Sei'alNa 749,474 .5 Claims. (Cl. 200e-156) The present invention relates to electric switches and more `particularly :of the push and pull type `by which to and fro motion of the plunger causes a switch to close a circuit.

An object of the .present invention is to provide a switch :in which an actuating plunger drives a switch operating ratchet wheel two steps in the same direction of rotation in response to two successive opposite movements of the plunger.

Another object of the present invention is to provide an indexing mechanism that will have a positive action but at the same time can be actuated with the minimum of eiiort. The indexing mechanism yis such that it will "maintain the plunger of the switch inleither `of vits actuated positions lregardless of `shocks or vibrations that may be applied to the switch housing or the control structure. i

Another object of the present invention is to provide an improved switch mechanism by which each movable contact .of several is moved to four successive on positions and then to two successive c positions, Vbut `alwayshavingtwo of the several :movablecontacts in on position at the same time. This-distributes the contact-duty among theseveral movablecontacts so `that they are capable of use for long periods without replacement.

Further objects and advantages of the `present invention will be 'apparent from the following description, reference being `had to the accompanying -drawings wherein a preferred embodiment of :the present-invention is clearly shown.

In the drawings:

Fig. 1 is a -planfview of the switch embodying the present invention.

Fig. 2 is a sectional view taken on line :2-2 of Fig. `1.

Fig. 3 is a view similar to Fig. l1 with the tex minal plate and the movable contact of the switch removed with the plunger in one of its positions.

Fig. 4 is `a view similar to Fig. "3 but showing the plunger in `another position.

Figs.l5and 6 are sectional -views taken on lines 5-5 `and 6-B, respectively, -of Fig. `3.

Fig. 711s a plan view of a movable contact used in this switch.

Fig. 8 is a diagrammatic Aview of the switch, the elements being :projected upon a single plane to illustrate the relation of the cooperating parts.

Referring to the drawings 2D designates a switch ,casing having an upwardly rextending sleeve 2l, a partition f2.2 and a.housing `23 *having 2 an open s ide closed :by a .closure or block 2&4 `of insulatingmaterial. The open end of `the housing is :recessed toprovide alperipheral shoulder and a .peripheral iange 26. Theplosureis `held against the shoulder by deforming `the flange 426` at .several places Vagainst the outer surfaces of the cover. It is to be understood that other means may be used `to `secure the block to the housing. For example, 4the housing 23 could be formed with tangs andi/bent over exterior surface of the closure `2li to `force the closure against the rimof the housing.

The bottom wall -ot `the housing 23 and the closure 2li Vare provided rwith recesses in direct alignment witheach other to support a rod or shaft 28. The shaft loosely supports a driving or ratchet `wheel stamped from sheet metal. In this instance the wheel is formed with six equally spaced openings 3l, each opening having two `straight side edges 3m which act as ratchet teeth.

A plunger 32 stamped from heavy sheet metal is formed `with an enlarged portion 33 and a reduced `portion 34 to form afshoulder 35. The reduced portion 34 extends through an aperture `36 formed inthe `partition 22. This Aopening is complementary tothe contour of the reduced portion and assists in guiding the plunger 32 into steady straight line movements of the plunger. The enlarged Yportion 3.5 of the plungerhas a slot 3l which straddles the shaft 28. The slot is also adapted uto'straddle aaprojection or lug 38 formed on the interior of the `bottom wall 27 of the nous ing 23. The lug '38 will extend into the slot 3l upon downward movement of the plunger to assist in .guiding the plunger 32 in its straight line movement. The enlarged `portion 33 of the plunger :32 is `provided with two projections ll and Al one` o n each side of the slot 31. The projections Vit() and ,lll aretapered as shown in Fig. 5 and Figf. The `taper1of the `projection l0 is oppositeto that of theprojectioni to be described.

The wheel 30 is provided with a tongue l2 bent at an angle Vto the plane of the wheel and ntsfinto a slot 43 of a movablecarrier i4 of nonconducting material and is loosely supported on theshaft 2.8. The tongue `l2 drives the movable carrier around the shaft 28. The face of the movable carrier 44 adjacent `the closure supports a bridging 1member 45, see Fig. "7, having three arms 46 extending radially from a central portion till. Each arm is `provided with a detent portion 49. The contact 45 is `also :provided with a plurality of tongues :each of :which extend into .suitable openings `5| Vprovided by the carrier, to anchor 3 the bridging member thereon. The detents 49 formed on the arms are so shaped to receive rounded heads of conducting rivets or distributing terminals 55, 56, 51 and 58 carried by the block 24 and rounded bosses 59 formed on the inner face of the closure 24. The rivets are arranged consecutively in a circular row and hold conducting plates in recesses provided on the outer face of the block 24. The rivets 55, 56, 51 and 58 are connected to conducting plates suitably supported on the exterior face of the cover or block 24. In this instance the rivets 55 and 56 extend through the closure 24 and through suitable openings in a conducting plate 59a. The rivets 55 and 56 are pinned over to hold a plate 59a firmly in a recess in the exterior face of the closure 24. The plate 59 mutually connects the two rivet terminals 55, 56 and is connected with the current supply. The rivets 51 and 58 respectively extend through the closure 24 and through v openings in independent conducting plates 69 and 6| and riveted over to hold their respective plates firmly in recesses provided on the exterior face of the closure 24. The terminals 51 and 58 are the current distributing terminals.

It will be noted that the rivet heads 55, 55, 51, 58 and the bosses 59 are arranged successively in a circular row to provide six positions to which the movable contact can be rotated. The term'inals 55, 55, 51 and 58 cooperate with the arms 49 to establish circuits alternately between the current supply terminals 55, 56, and the current distributing terminals 51 and 58.

A compression spring 10 intersposed between the movable carrier 44 and the ratchet wheel 39 operates in two directions. When the closure 24 is assembled to the housing 23 the spring 19 will be compressed. The spring urges the carrier 4|) and Contact 45 toward the closure and the ratchet wheel 39 against the enlarged portion 33 of the plunger 32. The spring 19 provides the necessary pressure to eiect good contact engagement between the movable contact and the rounded head of the terminals and yet permits relative axial movements of the wheel 36 and movable Contact 45 on the shaft 28.

Referring to Fig. 2, it will be observed that in this instance that the plunger 32 must be actuated manually to either of its positions. The plunger is prevented from moving -accidentally from either of its actuated positions due to vibrations or jars by the detents 49 provided by the bridging member V45. The detents 49 set rmly on the rivets in any position. If desired an indexing mechanism may be provided to assist in preventing accidental movement of the plunger 32. One form of the indexing mechanism which may be used comprises a bearing member or ball 89 which is urged into one or the other of detents 8| provided in reduced portion 34 of the plunger 32, by a spring 82. The spring 92 is housed within a passage 83 provided in the partition 22 and held therein by a screw plug 84.

The reduced portion 34 of the plunger is attached at its upper end to a cap 85. In this instance the reduced portion 34 is riveted at 86- to the cap 35. The cap 85 telescopes the upper end of the sleeve 2| and thus assists in guiding the plunger in its reciprocable movements.

The operation of the switch is as follows: When the operator applies pressure to the cap 85, as viewed in Fig. 3, the plunger will move downwardly in a straight line through the co' operation of slot 31 and projection 38, plungerv portion 34 and opening 35, and the sleeve 2| and with another opening 3|.

the cap 85. When the plunger has moved a certain distance the projection 4D will engage one of the straight edges Sla to drive the wheel 39 in a clockwise direction. After the plunger has moved its full downward stroke the wheel 39 and contact 45 will be rotated one step equal to one-sixth of a revolution. As the plunger is moved downwardly the projection 4|- will engage a narrow strip of metal between two adjacent openings 3| to rock slightly the wheel toward the carrier. When that happens the spring will be compressed until the projection 40 registers When the plunger has reached its extreme downward movement as shown in Fig. 4, the plunger 32 is manually actuated to move the plunger from the position shown in Fig. 4 to that shown in Fig. 3, the projection 4| will engage a straight edge 3|a to move the Wheel 30 another step in the clockwise direction which is equal to one-sixth of a revolution. During the last mentioned step of rotationV the projection 40 will slide over another'- narrow strap between two adjacent openings 3|.3

The projection 40 will cause the wheel to tilt slightly until the projection 40 registers with another opening 3|.

plunger 32 is reached.

It will be observed by reference to Fig. 7, that;

two of the contact arms 49 of the movable contacts engage stationary contacts and the otherl When the plunger 32 is actuated in either direction thearm engages one of the bosses 59.

movement of the movable contact 48 and the Wheel 3B will be in the direction of the arrow! A. Thus each contact arm will have four con` secutive on positions and two consecutive oi`i By this arrangement the duty of thecontaot arms is distributed so that they will positions.

have longer life.

The switch thus described may be mounted on a suitable support 9| such as the dash board 9B is screw-threaded upon the outer portion the shoulder 93 will bear against the underside of the support to hold iirmly the switch to the sup-V port 9|.

The present switch mechanism has been described by which each movable contact of sev-4 eral is moved to four successive on positions and then to two successive ofi positions but' always having two of the movable contacts in on positions at the same time.

needed in which case, of course, the switch would be of the off-on type. Further, if desired, a

return spring could be inserted between the par- Thus when the capis pushed in against the action of the spring thel spring would return the cap to its outermost position upon release of the force which pushed tition 22 and the cap 85.

the cap inwardly.

While the embodiment ofthe present invention as herein disclosed, constitute a preferred'I form, it is to be understood that lother forms' When the shoulder 35 eny gages the under side of the upper Wall 99 of thel housing 23 limit of outward movement of the It will be: obvious to persons skilled in the art that it will'4 be equally easy to use the present switch mechanism where only two stationary terminals are might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. A switch comprising in combination; a casing; a closure for the casing carrying stationary contacts; a stud supported by the casing and closure; a manually operated actuator slidably supported by the housing perpendicular to the axis of the stud, said actuator having a slot through which the stud projects to guide the actuator in straight line movements; a disc rotatably supported on the stud; ratchet provisions provided by the actuator on each side of the slot and capable oi extending into openings provided by the disc to move the disc step-by-step in one direction of rotation only upon opposite movements oi the actuator; a carrier mounted for axial and rotary movements on the stud and carrying a bridging member adjacent the stationary contacts; means provided by the disc for driving the carrier whereby the carrier rotates with the disc at all times; spring means disposed between the carrier and disc tending to urge them apart and maintain the ratchet provision effective; and means for yieldingly holding the actuator in any one of its actuated positions.

2. In combination; a casing; a closure for the casing; a rod within the casing having one end supported in the casing and having the other supported in the closure; a slotted plunger reciprocably mounted in the casing with the slot of the plunger straddling the rod; an actuator rotatably supported on the rod and provided with a series of openings arranged in a circular row; ratchet provision provided by the plunger on each side 1 of the slot, each provision extending into an opening whereby the plunger rotates the actuator in one direction only by two successive opposite movements of the plunger; and spring means for urging the actuator against the plunger for maintaining the ratchet provisions effective.

3. In an electric switch, having six positions arranged in a circular row, four of said positions including stationary contacts arranged consecutively with two of the adjacent contacts being mutually connected; a rotary disc carrying a contact having three fingers with one of the fmgers always engaging one of the mutually connected contacts and another linger engaging one of the other contacts, an actuator driving the disc, said actuator rotatably mounted with respect to the carrier and having ratchet openings arranged in a circle; a reciprocatory plunger provided with two projections adapted to extend into respective openings of the disc on opposite sides of the center of the actuator to impart two movements in the same direction of rotation to the actuator CJI by two opposite movements of the plunger; and spring means for urging the actuator against the plunger to maintain the ratchet provision effective.

4. A switch comprising, stationary contacts arranged in a circular row; a movable contact rotatably supported relative to the stationary contacts; means mounted for axial and rotary movements relative to the movable contact and having means loosely connected to said movable contact for driving same; a reciprocable rod; ratchet provisions between the rod and the driving means cooperating to rotate the driving means in steps intermittently, said ratchet provisions being so arranged that the driving means will be moved one step in one direction of rotation only upon full actuation of the rod in either direction; and resilient means disposed between the contact and the driving means for urging the movable contact toward the stationary contacts and the driving means against the rod and thereby maintain the ratchet provisions effective.

5. An electric switch including, a switch casing; a closure for the casing carrying stationary contacts arranged in a circular row; a stud supported by the casing and the housing; bridge means supported on a carrier rotatably and axially movable on the rod; a manually operated plunger extending into the casing and having a slot straddling the stud whereby the plunger is guided in straight line movement; a disc rotatably and axially movable on the stud; ratchet provisions between the plunger and the disc of which a part is provided on each side of the slot and a circular row of abutments is provided by the disc; means associated with the disc having a slidable spline connection with the carrier whereby the disc and carrier rotate together at all times while permitting axial movements relative to each other; resilient means carried by the stud functioning to urge the carrier toward the closure and at the same time press the disc against the plunger whereby one part or the other of the ratchet provisions provided by the plunger will cooperate with one abutment of the disc to rotate the latter in one direction of rotation only upon manual operation of the plunger in either direction.

WILLIAM EARL BROWN.

REFERENCES CITED The following references are of record in the ile of this patent:

UNITED STATES PATENTS Number Name Date 2,283,630 Hill May 19, 1942 2,324,844 Hutt July 20, 1943

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