US2338305A - Electric control switch - Google Patents

Description

Jan. 4, 1944. SIMMON ELECTRIC CONTROL swucn 4 Sheets-Sheet 1 Filed June 2, 1942 INVENTOR: Alfred Sim/non h/mz WWW 'A'ITORNEY.

Jan. 4, 1944.

A. SIMMON- 2,338,305

ELECTRIC CONTROL SWITCH Filed June 2, 1942 4 Sheets-Sheet 2 Fig.- 2

INVENTCR: Alfred Sim/110m BY Wm. WM

ATTORNEY.

Jan. 4, 1944. I $|MM0N 2,338,305

ELECTRIC CONTROL SWITCH Filed June 2, 1942 4 Sheets-Sheet 3 INVENTOR:

Alfred Simmon ATTORNEY.

Jan. 4, 1944. SIMMQN 2,338,305

ELECTRIC CONTROL SWITCH Filed June 2, 1942 4 Sheets-Sheet 4 INVENTOR:

Alfred Sim/non BY Wm 2. Wm

' ATTORNEY.

Patented Jan. 4,' 1944 ELECTRIC CONTROL swrrcn Alfred Simmon, Jackson Heights, N. Y., assignor to Simmon Brothers Inc., Long Island City, N. Y., a corporation of New York Application June 2, 1942, Serial No. 445,422

3 Claims.

merely allowing a fixed time for certain'operations and simply initiating the next operation after the lapse of an appropriate length of time. For the main tools, the first expedient is usually more satisfactory since in this way one is certain that one tool has performed its function before the next tool starts its work. On the other hand, for many minor operations such a system would be unnecessarily cumbersome, and it is then preferable to control these operations by some sort of time switch. Minor operations of this character are, for example, the actuation of the collet in order to feed new stock, the release of a blast of compressed air in order to blow away chips, and 'many others.

The particular purpose of this invention is to provide a simple switch which performs both before mentioned functions. This is accomplished preferably by providing a rotating drum which is driven intermittently 'by an electric motor, this rotating movement being controlled by a solenoid actuated escape mechanism.

In the drawings in which a preferred embodiment, of an electric control switch embodying the principles of the invention is shown,

Fig. 1 is an isometric view of the, switch with its escape mechanism shown at the rear end of its operating drum instead of at the front for better illustrating the operation and in which the housing and other supporting members are omitted for sake of clearness;

Fig. 2 is an elevational end view of the switch and its support; 7

Fig. 3 is a sectional view, partly in elevation, along the plane of line 33 in Fig. 2; and

Fig. 4 is a rear elevational view of the same.

All parts are shown more or less diagrammatically.

Like characters of reference denote similar parts throughout the several views and the following specification.

With reference to the drawings, the main element of the control device is a rotating drum H which is driven through a train of gears 12 by a small motor l3. This motor must be of such design that it can be stalled for relatively long periods of time without overheating, such type being generally referred to as a torque motor. In other words, the drum is not continuously rotated but is merely urged by the motor to rotate in the direction indicated by the arrow.

A suitable number of holes are drilled and tapped into the circumference of the drum so that buttons H can be mounted therein wherever necessary by means of screws Ila. These buttons actuate small switches 15, so-called micro-switches, which control the various circuits of an automatic machine or an automatic machine tool.

In Fig. 1, I have shown seven switches i5 which may, for example, control respectively the following circuits of a typical automatic machine tool: Switches #1 and #2, motor forward direction; switches #3 and #4, motor reverse direction; switch #5, reciprocating movement of the tool-supporting turret; switch #6, reciprocating transverse movement of an additional tool holder; and switch #7, collet release in order to feed new stock. It will be understood that this is merely an example and that any other number of circuits may be controlled in the same manner if necessary. In Figs. 2, 3, and 4, nine micro-switches l5 are shown which, however, are arranged in two rows of four and five, respectively, in order to conserve space. The operation of the device is, of course, in no way affected by this different physical arrangement. The sequence of operations is controlled by the location of the buttons M on drum H and it is a particular advantage of this invention that their locations and thus the sequence of operations can be changed quickly and conveniently.

As mentioned above, the rotation of the drum is controlled by an escape mechanism which consists of two levers ii and I8 which are linked by a connecting rod I9. These levers are urged in one direction by a spring 20 and in the other direction by solenoid 2!. This solenoid in turn is controlled by one or several limit switches of the automatic machine tool so that it will be actuated as soon as one tool finishes its opera tion. Levers H and I8 have suitable abutments Fla and 18a projecting at right angles therefrom the drum is permitted to make a fraction of a revolution. In this particular instance provisions are made to mount twenty pins so that the drum would advance 18 degrees for each current impulse received by the solenoid.

However, it is not necessary that these pins are equally spaced and one or several of them may be omitted whenever desirable. I'have, for example, shown gaps of this type in Figs. 1 and 2.

It will be clear that whenever the last pin preceding such a gap passes through the escapement that then the drum will continue to rotate for the length of the gap and that during that time a number of timed operations may be automatically performed. The timing of these operations depends, of course, upon the length of the switch depressing buttons l4 and upon the speed with which the drum rotates. This control switch will therefore Operate as a step relay as long as pins 23 are provided at regular intervals, but whenever larger gaps occur between pins, the device will work as a time switch causlng timed operations to occur automatically.

To complement the device, in Figs. 2, 3 and 4 are also shown a main switch 24 and a small transformer 25 which are necessary for the operation of a machine tool to be controlled by" the device forming the subject of this invention. These parts, however, are conventional and do not form a part of the invention proper.

It is understood that various changes in the form, proportion and minor details of construc-' tion may be resorted to without departing from the principles or sacrificing any of the advantages of the invention, as defined in the appended claims.

What I claim as new is:

1. In an electric control switch, a revolving drum, stops on said drum, an escape mechanism adapted to engage said stops, said mechanism having two iulcrumed levers, each-lever havin a projection, a cross bar connecting said projections, a solenoid operatively connected to one of said levers, each of said levers having projecting abutments in spaced relation to each other to straddle one of said stops, the abutment of one of said levers being in position for engaging one of said stops while the abutment on the other lever is out of line of engagement with said stop when actuated by said solenoid, and vice versa.

2.In an electric control switch, a revolving drum, stops on said drum, an escape mechanism adapted to engage said stops, said mechanism having two levers fulcrumed at their centers and having each a. projection therefrom, a cross bar connectingsaid projections, a solenoid operatively connectedto-one of said levers, each of said levers having projecting abutments in spaced relation to each other to straddle one of said stops, the abutment of the solenoid connected lever being out of line of engagement with one of said stops while the said other lever is engaging said stop, and vice versa.

3. In an electric control switch, a revolving drum, stops on said drum, an escape mechanism adapted to engage said stopspsaid mechanism solenoid, and vice versa.

ALFRED SIMJVION.

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