US2508692A - Switch - Google Patents

Description

Patented May 23, 1950 UNITED STATES PATENT OFFICE 3 Claims.

This invention relates to, and it is an object to provide, an improved electric switch of manually actuated type; such switch being especially designed for industrial or commercial use, and particularly in connection with reversible electric motors of the type which require a three-wire control circuit.

Another object of this invention is to provide an electric motor reversing switch which include a novel contact assembly arranged to be actuated by a. finger lever, to establish a circuit between a common lead wire and either of the remaining pair of lead wires, selectively, of a threewire circuit.

A further object of the invention is to provide an electric motor reversing switch which includes a finger lever movable from a central or off position to selective on positions on either side of said central position, whereby to reversibly actuate the motor; the switch bein constructed so that by the simple substitution of one for another removable part of the contact assembly, the

switch .can be made to automatically "hold" in one or both on positions, or to automatically return to the central or off position when hand released from one or both of said on positions. The switch is thus readily adaptable to different uses.

A further object of the invention is to produce a simple and inexpensive device, and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the followin specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views:

Figure l is :a, longitudinal sectional elevation of the improved switch.

Figure 2 is a transverse section on line 2-2 of Fig.1.

Figure 3 is a plan view of the contact plunger, detached.

Figure 4 is a, longitudinal sectional elevation, embodying a modified type of contact plunger.

Figure 5 is a longitudinal sectional elevation embodying a still further modified type of contact plunger.

Referring now more particularly to the character of reference on the drawings, and at present to Figs. 1-3 inclusive, my improved switch comprises a body I of dielectric material; said bddy including, at the back thereof, a, removable cap 2 forming a chamber 3 between the body I and the back wall of said cap.

Intermediate its ends and centrally of its sides the body i is formed with a slot 4 which extends through said body from front to back. A finger lever 5 is pivoted in the slot 4 on a removable cross pin 6, the outer end of said lever projecting beyond the front of the body I for finger engagement.

At its inner end and rearwardly of the cross pin 6 the lever 5 is formed with a fork l which engages in opposed notches 8 cut in opposite sides of a longitudinally extending, elongated contact plunger 9 slidably seated at opposite ends in opposed alined bores I i! and l l formed in the body I on opposite sides of the slot 4. It will be seen that with swinging movement of the finger lever 5 in one direction or the other, the fork '1 will cause a corresponding but opposite movement of the elongated contact plunger 9.

A pair of cylindrical contacts, indicated at l2 and 53 respectively, project into the body I from the chamber 3 and intersect the bores l0 and II respectively at points adjacent the ends thereof; the contact plunger 9 being of such length that when the finger lever 5 is in a central position, i. e. at right angles to said plunger, the ends of the latter are disposed adjacent but short of the contacts 12 and l3. The contact I2 is removable, whereby to permit of removal of the contact plunger 9 from the body through an end opening in the bore l0 which is normally closed by a screw plug 54. With swinging movement of the finger lever 5 in one direction the plunger 9 will engage the contact l2, while movement of the finger lever in the other direction will cause such plunger to engage the contact I3.

A contact pin I5 slidably engages through the body from the back to the bore Ill and there constantly rides against the adjacent portion of the plunger 9. At its outer or rear end the contact pin l5 extends somewhat beyond the back of the body I and is fixed in connection with a leaf spring I 6 which extends in the .chamber 3 to connection with a terminal I! mounted on a, cross plate I 3 intersecting the slot 4 at the back of said body. The terminal i1 is connected with the common lead wire I9 of a three-wire cable 20 incorporated in the control circuit for a reversible electric motor (not shown). The other two wires of the cable 26 are indicated at 2| and 22, and said other wires are connected to the .cylindrical contacts l2 and I3, respectively, by means of screws 23 threaded into said contacts from within the chamber 3.

When the finger lever is swung in a direction to engage the plunger 9 with the contact [2, the circuit is closed through wires l9 and 2|, while movement of the finger lever in the opposite direction to engage the plunger with contact l3 closes the .circuit between wires [9 and 22.

When the finger lever 5 is in center position the switch is off relative to the bore contacts l2 and I3, and the. plunger 9 is then held. in a corresponding positionclear of said contacts by a spring-pressed detent 2-4 disposed in a bore in the body opposite the contact pin 15, such detent engaging in a socket in the plunger.

In the embodiment of Fig. 1 the switch is arranged so that when the circuit. is closed through wires l9 and 2| by swinging the finger lever 5 in a direction to engage the plunger with contact l2, the switch is automatically maintained in such closed position by reason of the provision of a further socket 25 in the plunger, and into which socket 2Sthe spring-pressed detent 24 then engages; To'return the switch to its neutral or oil position'itis' necessary to manully actuatethe fingerlever 5.

However; whenthe switch'is' closed in the opposite direction. i. e. with'plunger. 9 engaging contact l3,'it'is automatically returned to off positionwhen the lever 5 is released. This is accomplished by the provision of a compression spring 21 surrounding the plunger 9 between the fork l and the body I in the direction of said contact I3."

Thus, with the switch arranged as in Fig. 1, it

will automatically remain closed for the circuit comprising wires l9 and 21', butwill automatically open when the lever is released for the circuit comprising wires 19 and 22'.

In'the embodiment shown in Fig. 4 the general assembly of the switch remains the same, but here the switch is provided with. a plunger 28 which includes solely a single socket 29, for the reception of the spring-pressed detent 24 when the swi'tchis in off position. In this embodiment compression springs 30 and 3i surround the plunger 28 on opposite sides. of the fork 1, whereby the switch automatically returns to off position fromeither on position when manually released' In the embodiment of Fig. 5, the general assembly of the switch still remains the same, but here the plunger 32 includes threev detent receiving sockets in longitudinally spaced relation adapted to receive the detent 24, said sockets beingindicated at 33, 34, and 35. When the detent seats in notch 33 the switchis. in off position, as is obvious, while the sockets 34 and 35 serve to releasably lock. the switch in on position relative to-the contacts I2 and I3, respectively. In this embodiment no return springs are used, and the switch will remain in either on position until manually returned to off position.

The embodiments of Figs. 1, 4, and 5 are adapted, as is obvious, to various switching requirements, depending on the-nature of the use to which the controlled motor-is tO-be put.

As is evident, the switch may be readily converted from one type to the other, merely by the substitution of different plungers, and in certain instances the addition or renewal of one or more of the compression springs. The remainder of the assembly remains unchanged.

From the foregoing description it will be readily seen that there has been produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new and useful and upon which Letters Patent is desired:

1. A switch comprising a dielectric body pro-- vided with a slot cut into the'face thereof, the body being. also provided with a .pair. of alined bores extending respectively to opposite sides or the slot, a pair of fixed electric contact members,v each such contact member. projecting into one.

with the third contact member and normally out of engagement with both'of the pair of contact members; and means movable in the slot and connected with the plunger and operable. to selectively move the plunger'intoengagement with one or the otherof said-pair of-contact members.

2. A switch, as in claim' 1 in which. the. plunger is provided with a notch in its surface..- and an element slidabl mounted in the body and yieldably engageable with the plunger when the latter is in a predetermined position in the bores.

3. A switch as in claim 1 in which the plunger operating means is a finger lever pivoted in the slot, the inner end of the lever being in operative engagement with the plunger, and a spring interposed between such lower end of the lever and the opposite side of the slot;

MANUEL O. SOUZA.

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

UNI-TED STATES PATENTS Number Name Date 1,808,316 Osigan June 2, 1931 1,812,410 Meurer June 30, 1931 1,949,568 Gotham Mar. 6, 1934 2,242,167 Bentley May 13, 1941 2,413,135 Baumgardner Dec. 24, 1946

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