US2404644A

US2404644A - Control of electric devices

Info

Publication number: US2404644A
Application number: US500357A
Authority: US
Inventors: Lowe Bernard
Original assignee: Individual
Current assignee: Individual
Priority date: 1943-08-28
Filing date: 1943-08-28
Publication date: 1946-07-23
Anticipated expiration: 1963-07-23

Description

July 23, 1946. B. LOEWE NOW BY JUDICIAL CHANGE OF NAME v B. LOWE CONTROL OF ELECTRIC DEVICES Filed Aug. 28, 1945 I INVENTOR. fimmzzn 50m? Patented July 23, 1946 CONTROL OF ELECTRIC DEVICES Bernhard Loewe, Yonkers, N. Y., now by judicial change of name Bernard Lowe Application August 28, 1943, Serial No. 500,357

2 Claims.

The object of the invention is an improvement in the control of electric devices.

It is a purpose of the invention to provide for such devices a novel type of foot switch control using for the switch proper an ordinary standard type encased hand operable switch, e. g. a switch of the kind on sale in all department and hardware stores, and using for the foot operation of said hand switch an actuator device adapted to be combined with said hand switch.

Other purposes and advantages of the invention will become apparent from the following description in connection with the accompanying drawing showing some embodiments of the invention by way of example.

In said drawings Figure 1 is a vertical longitudinal through one form of the new actuator;

Figure 2 is an elevation of the tumbler cam of the actuator shown in Figure 1.

The device shown in Figure 1 works according to the known principle that the switch is closed by one depression of the actuator and remains closed until it is opened by a subsequent or second depression of the actuator.

Th device uses as the switch unit proper the commercial standard type encased tumbler hand switch 25 to be connected with the actuator transmission by mere overlapping i. e. without requiring any alteration of the tumbler 26, holes, notches, etc., in the latter.

The hand type switch 25 is attached, preferably in an easily detachable manner, to a base plate 36 to which is secured at 3!v a treadle 38 held in elevated position by a U-shaped leaf spring 39.

For transmitting the movement of the treadle 38 to the tumbler 26a pusher or bar 40 is pivoted at 4| to the treadle and is normally held centered in the position shown by the springs 42 and 43.

A projection 44 of this bar engages into a slot 54 of a tumbler cam designated generally by the number 46 and shown separately in elevation in Figure 2.

This cam is rigidly attached to the tumbler 26 by overlapping being clamped onto said tumbler by means of one or more side bars 41 and clamping screws 48 engaging in threaded holes 49 of the cam. Thus for all purposes the cam 46 may be considered as a tumbler directly secured immovably to the tumbler shaft 50.

The cam 46 has a central part provided with a notch 52 adapted to fit over the tumbler 26. The part 5| having the form of an inverted V with a rounded apex 53 is surrounded by the slot 54 of similar shape.

section In the positions of the parts as shown the circuit is supposed to be open.

Upon depressing th treadle 38 the projection 44 engages the incline 55 of the cam part 5| and is thereby deflected to the left, tensioning the spring 43 and reducing somewhat the tension of the spring 42. When the projection 44 reaches the left end 56 of the slot 54 the cam and the tumbler rigidly connected therewith is swung anticlockwise whereby the circuit is closed.

As soon as the treadle 38 is released it rises whereby the projection 44 is raised in the slot 54. As soon as the projection 44 reaches the upper part of the cam and slot the spring 43 draws the bar 4|] to the right side of the apex 53.

The circuit thus remains closed.

When the treadle 38 is depressed again the projection 44 now rides down the right side 51 of the cam part 5| until it reaches the right end 58 of the slot 54 whereupon it rocks clockwise the cam and tumbler around the axle back to the position shown in Fig. 1 thereby opening the circuit.

By the just described movement the spring 42 has been tensioned and the spring 43 has been slackened.

When the treadle 38 is released again it rises, the projection 44 rises in the slot 54, and the bar 4|! is pulled back by the spring 42 to the left side position shown in Figure 4.

It is to be noted that the pivot 4| connecting the push bar 40 with the treadle 38 does not move down and up in a straight vertical line, but moves in an arc of a circle as indicated by the arrow 59. This curved movement would cause trouble if the cam 46 would be symmetric like similar cams used in push button switches, i. e. if the cam parts and 51 were absolutely equal.

To avoid such trouble said cam 46 is slightly asymmetric, just enough to compensate for the curvature of the arrow 59.

Of course, in all modifications of th object of the invention any suitable or well known means, if deemed desirable, may be used for relieving the tumbler shaft from part of the actuating pressure.

Instead of the simple two-pole tumbler switch shown any other standard type hand switch with two or more poles may be used, of course with corresponding self-evident alterations of the actuating mechanism.

What I claim is:

1. As an article of manufacture an actuator for closing and opening by successive strokes of downwardly directed foot pressure a standard type encased hand operable switch, said actuator comprising, in combination, two main parts, one of which is a base, and the other of which is a treadle attached to said base, said treadle adapted to be swung downward by foot pressure and upward by elastic force, and transmission means connected with at least one of said main parts, said transmission means comprising a bar pivoted to said treadle and an asymmetric cam, in the form of a V, adapted to be swung in two different 10