US3027441A - Electric switch - Google Patents

Description

March 27, 1962 .1. H. MULLEN ETAL ELECTRIC SWITCH 2 Sheets-Sheet 1 98 2 7 42 3 5 9 2 1 22 F 6 at m e H m e l 3 m 3 March 27, 1962 MULLEN ETAL ELECTRIC SWITCH 2 Sheets-Sheet 2 Filed Sept. 6, 1957 Flg 4 Fug 5 INVENTORS John H. Mullen 8| WITNESSES Hire Patent house Electric (Iorporation, East Pittsburgh, Pa., a corporation of Pennsylvania Filed Sept. 6, 1957, Ser. No. 682,486 2 Claims. ((31.200-167) This invention reiates, generally, to electric switches and, more particularly, to switches of a type generally known as selector switches.

Selector switches are utilized in control systems to control the operation of electric motors and other electrical apparatus. It is desirable to utilize indicating lights in conjunction with the switches to provide an indication of the functioning of apparatus located remotely from the switchboard or control panel containing the selector switches. Heretofore, the indicating lights have been mounted separately from the selector switches, thereby increasing the amount of space required for mounting the switches and the lights. Furthermore, there was a possibility of an operator becoming confused in determining which light corresponded to a particular switch when a plurality of lights and switches were mounted on the same panel.

An object of the invention is to provide a combined selector switch and indicating light unit.

Another object of the invention is to provide a rotary selector switch of a snap-acting type.

A further object of the invention is to provide a rotary selector switch which is sealed against the entrance of foreign matter into the switch mechanism.

Still another object of the invention is to provide an improved control system utilizing a combined selector switch and indicating light.

Other objects of the invention will be explained fully hereinafter or will be apparent to those skilled in the art.

In accordance with one embodiment of the invention, a spring-return snap-acting switch is actuated by a rotatable cam driven by a combined indicating light and operating unit. The lens for the light functions as the operating member for rotating the cam which retains the switch in the position to which it was last actuated.

For a better understanding of the nature and objects of the invention, reference may be had to the following detailed description, taken in conjunction with the accompanying drawing, in which:

FIGURE 1 is a view, partly in section and partly in elevation, of a combined selector switch and indicating light embodying the principal features of the invention;

FIG. 2 is a view, in bottom plan, of the operating unit for the switch;

FIG. 3 is a view, in bottom plan, of the switch and terminal unit for the structure shown in FIG. 1;

FIG. 4 is a diagrammatic View of a control system utilizing a combined selector switch and indicating light unit;

FIG. 5 is a diagrammatic view of a reversing system utilizing a combined selector switch and indicating light unit in conjunction with two push-button switch units; and

FIG. 6 is a diagrammatic view of another control system utilizing two of the combined selector switch and indicating light units.

Referring to the drawings, and particularly to FIG. 1, the structure shown therein comprises a supporting sleeve 10, preferably composed of a cast metal, and having a flange 11 at the inner end thereof for engaging the inner side of a supporting member or panel 12. A sealing disc 13, preferably composed of rubber or the like, is inter- "ice posed between the flange 11 and the inner surface of the panel 12. The outer end of the sleeve 19 is threaded externally for receiving a clamping ring 14 which is adapted to secure the sleeve to the panel 12 when the clamping ring is drawn down tightly. A metal washer 15 may be provided between the clamping ring 14 and the outer surface of the panel 12.

The supporting sleeve 10 is provided with a transversely extending web 16 having an opening 17 therein. A housing 18 is rotatably disposed in the sleeve 10. The lower end of the housing 18 extends through the opening 17 in the web 16. The upper end of the housing 18 is enlarged and threaded internally to receive a lens 19 which may be utilized to rotate the housing 18, as will be described more fully hereinafter. A sealing washer 21 is provided between the lower end of the lens 19 and a ledge 22 on the housing 18. A set screw 23 extends through the side of the housing 18 to engage a flattened portion or groove in the side of the lens 19 to retain the lens in the housing.

A lamp receptacle 24 is disposed inside the housing 1% and a lamp bulb 25 is disposed in the receptacle 24. The bulb 25 is protected by the lens 19. The receptacle 24 is retained in the housing 18 by a projection 26 which extends through an opening in the bottom of the housing 18 and also extends through an opening in a cam member 27 which is attached to the bottom of the housing 18 by riveting the projection 26 where it extends through the cam 27. The cam 27 also engages the bottom of the sleeve 10 to retain the housing 18 in the sleeve.

A compression spring 28 surrounds the housing 18 between a shoulder 29 and a metal washer 31. A sealing disc or washer 32 is provided around the housing 18 between the metal washer 31 and the web 16 of the sleeve to prevent oil or other material from passing through the opening 17. The spring 23 compresses the sealing disc 32 and biases the housing 18 outwardly. However, as previously explained, the outward movement of the housing 18 is limited by the cam 27 which engages the bottom of the sleeve 10. Inward movement of the housing 18 is prevented by the shoulder 29 which bears upon a ledge 33 on the sleeve 1%. Thus, the housing 18 is free to rotate in the sleeve but cannot move longitudinally in the sleeve, and cannot operate the switch by being pushed inwardly.

One leg of an L-shaped bracket 34 is attached to projections 35 on the bottom of the sleeve 11 by screws 36. A terminal block 37 is attached to the one leg of the bracket 34. The terminal block 37 is provided with terminal connecting screws 38 for making electrical connections to the block. If desired, a transformer may be provided in place of the terminal block, thereby changing a voltage applied to the lamp 25, and the connections may be made to the terminals of the transformer.

An enclosed switch 41 is attached to the other leg of the bracket 34 by means of screws 42. The switch -1 is preferably of a double-throw spring-return snap-acting type such as, for example, the switch described in Patent No. 1,960,020. The switch 4 1 is provided with an operating plunger 43 which is engaged by the cam 27 to actuate the switch when the housing 18 is rotated. As shown in FIG. 2, the cam 27 has a sloping surface which depresses the operating plunger 43 when the cam is rotated with the housing 18, which, in turn, is rotated by means of the lens 19.

The switch 41 is provided with contact members which control the energization of the lamp 25, as will be described more fully hereinafter. As shown, a terminal 44 of the switch 41 is connected to one terminal block 37 by means of a conductor 45. The lamp receptacle 24 is connected to the terminal block 37 by conductors 46.

As previously explained, the switch 41 is actuated by rotating the housing 18 which contains the lamp 25.

When the housing 18 is rotated a predetermined distance, the plunger 43 of the switch is depressed by the cam 27. The housing is retained at the predetermined angular position by means of a ball detent 47 which is pressed into an opening 48 in the sleeve it) by means of a spring 49. When the housing 18 is rotated in the reverse direction, the plunger 43 of the switch 41 is raised to its uppermost position by means of the spring-return mechanism within the switch 41.

As shown in FIG. 4, the combination indicating light and selector switch may be utilized in a control system to control energization of the actuating coil for a contactor M, which contactor may be utilized to control the operation of an elecric motor (not shown). When the indicating light is rotated the switch is operated to establish a circuit through contact members 51 and 52 of the switch, thereby connecting the coil of the contactor M across line conductors L1 and L2. As shown, the lamp is also connected across the line conductors L1 and L2 through the contact members 51 and 52 of the switch. Thus, the lamp 25 is energized simultaneously with the coil of the contactor M. Therefore an indication of the energization of the coil of the contactor is provided, which is consequently an indication that the motor controlled by the contactor M is running.

As shown in FIG. 5, one of the combination indicating light and selector switch units may be utilized in conjunction with two push button switches to control the operation of a reversing system for an electric motor. As shown, the system comprises a forward contactor F, a reverse contactor R, a forward push button switch 53, a reverse push button switch 54, and the combined indicating light and selector switch. Assuming that the contact member 51 of the selector switch is actuated to engage the contact member 52 of the switch, the forward contactor F may be energized by depressing the forward push button 53 to establish a circuit through contact members 55 of the forward switch. Thus, the coil of the forward contactor F is energized through a circuit which extends from the line contactor L1 through the contact members 51 and 52 of the selector switch, a conductor 56, contact members 57 of the reverse push button 54, contact members 55 of the forward push button 53, an auxiliary contact Ra of the reverse contactor R, and the coil of the contactor F to the line conductor L2. A holding circuit for the coil F is established through auxiliary contact members Fa on the contactor F. Thus, the push button switch 53 may be released after the contactor F is once closed.

The direction of operation of the motor controlled by the contactors may be reversed by actuating the selector switch to the off position, thereby deenergizing the forward contactor F, after which the selector switch is actuated to the on position, and the reverse push button 54 is depressed. When the button 54 is depressed an energizing circuit is established for the coil of the contactor R from the conductor 56 through contact members 58 of the forward push button 53, contact members 59 of the reverse push button 54, auxiliary contact members Fb of the contactor F and the coil of the reverse contactor R to the line conductor L2. A holding circuit for the coil of the contactor R is established through auxiliary contact members Rb, thereby permitting the push button 54 to be released after the contactor R is closed. The motor may be stopped by returning the selector switch to the oif position.

It will be noted that the indicating light 25 is energized through the contact members 51 and 52 of the selector switch when these contact members are closed to establish an energizing circuit for either the forward contactor F or the reverse contactor R depending upon the selective operation of the push buttons 53 and 54. Thus, the light 25 provides an indication of the energization of the reversing contactors which control the operation of the motor.

As shown in FIG. 6, two of the combined indicating light and selector switch units may be utilized in a system for controlling the operation of a motor having different operating speeds. Thus, the switches may control the energization of the contactor F1 which causes the motor to be operated at a fast speed and a contactor S which causes the motor to be operated at a slower speed. When the contact member 51 of one of the selector switches engages .the contact member 52 and a contact member 61 engages a contact member 62 of the other selector switch, the coil of the contactor F1 is energized by being connected across the line conductors L1 and L2.

At this time a light 64 which is rotated to operate the contact member 61 of the selector switch is energized. Also a light 65 which is utilized to operate the contact member 51 is energized. The light 64 may be colored green and the light 65 may be colored red. Thus, when both the red and green lights are on, they indicate that the motor is running at a fast speed.

If it is desired to operate the motor at a slower speed, the contact member 61 of the one selector switch is actuated to engage the contact member 63, thereby energizing the coil of the contactor S, which, as explained previously, establishes a circuit for causing the motor to operate at a slower speed. At this time the contactor F1 and the green light 64 are both deenergized. The red light 65 remains energized, thereby indicating that the motor is running at the slow speed. The motor may be stopped by actuating the contact member 51 of the first selector switch to the off position, thereby deenergizing both contactors and both indicating lights.

It will be noted that in each of the control systems it is not necessary to provide separate indicating lights to obtain an indication of the functioning of the devices controlled by the selector switches. The lamp which is utilized to operate the selector switch, by rotating the housing containing the lamp, functions as the indicating light for providing an indication of the energization of the device controlled by the switch. Therefore, the amount of space required to mount the control and indicating apparatus for a control system is reduced. Furthermore, the possibility of an operator becoming confused in selecting the proper switch to control the operation of a motor is reduced since the indicating light itself is utilized to operate the switch associated with the light. Also, the combined indicating light and switch unit is so constructed that it is sealed against the entrance of foreign material. Thus, if the switch unit is mounted on one wall of a cabinet, the switch mechanism is protected against the entering of foreign material into the mechanism.

Since numerous changes may be made in the abovedescribed construction, and different embodiments of the invention may be made without departing from the spirit and scope thereof, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

We claim as our invention:

1. A combined selector switch and indicating light comprising a supporting sleeve having a transverse web with an opening therein, a housing rotatably disposed in said opening, a spring surrounding said housing and biasing the housing outwardly, a lamp receptacle in said housing, a lamp bulb in said receptacle, a lens disposed in the housing over said bulb, an opening in the lower end of the housing, a cam engaging the lower end of the housing and having an opening therein aligned with the opening in the housing, a projection on the bottom of said receptacle extending through said aligned openings in the housing and the cam, retaining means on said projection engaging the cam to retain the receptacle in the housing, said cam engaging the web of the sleeve to retain the housing in the sleeve against the biasing force of said spring, said cam being rotatable with said housing, a spring-return switch supported by the sleeve, an operating plunger in said switch actuated by said cam when said housing is rotated, and contact members in said switch for controlling the energization of said lamp.

2. A combined selector switch and indicating light comprising a supporting sleeve having a transverse web with an opening therein, a housing rotatably disposed in said opening, an internal ledge in said sleeve, a shoulder on the housing bearing on said ledge, a sealing Washer surrounding the housing around the opening in said web, a spring surrounding the housing between said washer and the shoulder on the housing, said housing being biased outwardly by said spring, a lamp receptacle in said housing, a lamp bulb in said receptacle, an opening in the lower end of the housing, a cam engaging the lower end of the housing and having an opening therein aligned with the opening in the housing, a projection on the bottom of said receptacle extending through said aligned openings in the housing and the cam, retaining means on said rojection engaging the cam to retain the receptacle in the housing, said cam engaging the web on the sleeve to retain the housing in the sleeve against the biasing force of said spring, a spring-return switch supported by the sleeve, an operating plunger on said switch actuated by said cam when said housing is rotated, and contact members in said switch for controlling the energization of said lamp bulb.

References Cited in the file of this patent UNITED STATES PATENTS 2,043,054 Marty et al June 2, 1936 2,109,790 Batcheller Mar. 1, 1938 2,113,366 Batcheller Apr. 5, 1938 2,242,165 Batcheller May 13, 1941 2,262,458 Harrison Nov. 11, 1941 2,276,607 Bruno Mar. 17, 1942 2,278,629 Winning Apr. 7, 1942 2,339,196 Robbins Ian. 11, 1944 2,449,213 Frederick Sept. 14, 1948 2,452,916 Fleisehmann Nov. 2, 1948 2,462,594 Beal Feb. 22, 1949 2,803,816 Alden Aug. 20, 1957 2,841,663 Anderson July 1, 1958 2,914,705 Krystyan et a1 Nov. 24, 1959

Images