GB1572966A - Push-button operated electrical installation switch - Google Patents

Description

(54) PUSH-BUTTON OPERATED ELECTRICAL INSTALLATION SWITCH (71) We, BROWN, BOVERI & CIE AKTIENGESELLSCHAFT, of D 6800 Mannheim-Käfertal, Kallstadter Strasse 1, Federal Republic of Germany, a German Company, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The invention relates to an electric pushbutton switch, and particularly concerns such a switch in which the cover is penetrated by a display or indicating element which can be illuminated by a lamp provided in a socket of the appliance and in which a key element passing through the cover is controlled by a spring-loaded movable contact which is connected to a supply terminal and is movable against a counter-contact.

Devices of this kind are used particularly for operating the lighting in stair corridors, or they may serve as luminous bells. Their construction usually comprises a socket for the lamp, a cover and a push-button switch in which the push button in the form of a cap is mounted on the lamp penetrating the cover and is provided with a spring contact upon depression of which the fixed socket contacts are bridged to close a circuit. The lamp illuminating the push button is provided for the purpose of facilitating detection of the push-button switch in the dark.

German Patent Specification No. 834414 discloses a device of a similar construction, in which the push-button operated spring contact, instead of being mounted on the push button, is provided in the form of a singlearmed lever constituting a supply contact which is mounted on the socket and connected to two terminals and which, upon operation of the push button, is pressed against a second, fixed contact constituting a discharge contact which is connected to another terminal. In that known appliance, she push-button operated spring contact is a U-shaped leg spring through the clearance between the two arms of which a glow lamp is passed which then penetrates the cover and over which the inverted push-button serving as a key button is placed. Upon completion of its operation, the push-button is returned to its original position by the spring force of the leg spring.

This device is suitable for light push switches in which the circumference of the push-button does not substantially exceed the circumference of ihe glass bulb of the lamp and in which the clearance between the two legs of the leg spring does not substantially exceed the diameter of the lamp so that the push-button operating the leg spring can engage and depress both legs thereof. This construction cannot, however, readily be applied to other installations.

According to the invention there is provided an electric push-button switch comprising a socket, a support member for the socket, a lamp in the socket, a cover, an area of the cover being capable of transmitting light from the lamp, a push-button passing through cover spaced from the light transmitting area of the cover, said push-button having a depending push rod which is guided for movement between the socket and the support member, two electrical contacts on the socket which are enclosed by said support member, one of said contacts being engaged by the push rod and movable thereby to make or break electrical contact with the other one of said contacts when the push-button is depressed and spring means for returning the push-button from the depressed position when the push-button is released.

The one contact may be of angle shape. This enables one arm of the contact to be engaged, and moved, by the push rcå.

Likewise, the second contact may have an arm which is engageable by the movable arm of the one contact. This ensures a relatively simple construction.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 shows a section through the light switch along the line IIII of Figure 2, and Figure 2 shows a plan view of the light switch.

Referring to the drawings, the light switch shown in Figure 1 comprises a socket 1, a lamp 2, a cover plate 3, a cover frame 4, a light transmitting bottom plate 5, a light transmitting top plate 6 and a push-button arrangement 7.

The lamp 2 is a glow or incandescent lamp and is mounted centrally in the socket 1 of the light switch at a position sufficiently low to ensure that, in concealed or recessed installadons, the lamp just penetrates a supporting ring 8. The bottom plate 5 and the top plate 6, both of which are translucent, are mounted in a cover comprising the cover plate 3 and the cover frame 4. The cover plate 3 is penetrated by the translucent top plate 6 which has a substantially plane surface. An indicating or display plate 9 carrying, for example, a translucent inscription or a symbol, is inserted between the top plate 6 and the bottom plate 5; a coloured indicating plate may also be provided.

It will be noted from Figure 2 that the, in use, lighted area provided by the plates 5, 6 occupies a substantial area in the cover plate 3 and thus prevents accomodation of a pushbutton arrangement at a cenual position, since the size of the push button exceeds the size of the illuminated area serving as a light signal.

Also the various elements of the contact device to be operated by the push button cause obsuuction which prevent central location of the push-button. For these reasons, the pushbutton arrangement. 7 is provided laterally of the top plate 6 of the light signal. The pushbutton arrangement 7 comprises a push rod 10 carrying a push button 11; after its operation, the push button and the push rod are both returned to their original positions by two return springs 12 of coil-spring construction. The push rod 10, which penetrates the bottom plate 5, is guided between the socket 1 and a socket support 13, which is connected to the socket 1, by a momentary-contact or key device.

A movable contact 14 in the form of a single-armed spring contact which is connected to a terminal 15 is provided at the back of the socket 1. A counter < :ontact 16 is connected to a diametrically opposed second terminal 17. During operation of the pushbutton, a short arm 16a of the angular countercontact 16 contacts a contact stud or rivet 14a of the touch contact 14. Since the pushbutton 11 is of an elongate web-like con struction (see Figure 2) the surface area available for its operation is larger than before and the push button 11 thus matches the shape and the cover of the light signal.

This arrangement makes it possible to convert an existing non-push-button light switch into a push-button light switch simply by using the structural parts already available, it being merely necessary to insert the push-button or key device and to provide a socket support for the socket.

WHAT WE CLAIM IS: 1. An electric push-button switch comprising a socket, a support member for the socket, a lamp in the socket, a cover, an area of the cover being capable of transmitting light from the lamp, a push-button passing through the cover spaced from the light transmitting area of the cover, said push-button having a depending push rod which is guided for movement between the socket and the support mem- ber, two electrical contacts on the socket which are enclosed by said support member, one of said contacts being engaged by the push rod and movable thereby to make or break electrical contact with the other one of said contacts when the push button is depressed and spring means for returning the push-button from the depressed position when the pushbutton is released.

2. A switch according to Claim 1, in which said one contact comprises a spring of angle shape.

3. A switch according to Claim 2, in which said other contact has an arm for electrical contact with said arm of angle shape.

4. A push-button switch for an electrical installation, substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. Referring to the drawings, the light switch shown in Figure 1 comprises a socket 1, a lamp 2, a cover plate 3, a cover frame 4, a light transmitting bottom plate 5, a light transmitting top plate 6 and a push-button arrangement 7. The lamp 2 is a glow or incandescent lamp and is mounted centrally in the socket 1 of the light switch at a position sufficiently low to ensure that, in concealed or recessed installadons, the lamp just penetrates a supporting ring 8. The bottom plate 5 and the top plate 6, both of which are translucent, are mounted in a cover comprising the cover plate 3 and the cover frame 4. The cover plate 3 is penetrated by the translucent top plate 6 which has a substantially plane surface. An indicating or display plate 9 carrying, for example, a translucent inscription or a symbol, is inserted between the top plate 6 and the bottom plate 5; a coloured indicating plate may also be provided. It will be noted from Figure 2 that the, in use, lighted area provided by the plates 5, 6 occupies a substantial area in the cover plate 3 and thus prevents accomodation of a pushbutton arrangement at a cenual position, since the size of the push button exceeds the size of the illuminated area serving as a light signal. Also the various elements of the contact device to be operated by the push button cause obsuuction which prevent central location of the push-button. For these reasons, the pushbutton arrangement. 7 is provided laterally of the top plate 6 of the light signal. The pushbutton arrangement 7 comprises a push rod 10 carrying a push button 11; after its operation, the push button and the push rod are both returned to their original positions by two return springs 12 of coil-spring construction. The push rod 10, which penetrates the bottom plate 5, is guided between the socket 1 and a socket support 13, which is connected to the socket 1, by a momentary-contact or key device. A movable contact 14 in the form of a single-armed spring contact which is connected to a terminal 15 is provided at the back of the socket 1. A counter < :ontact 16 is connected to a diametrically opposed second terminal 17. During operation of the pushbutton, a short arm 16a of the angular countercontact 16 contacts a contact stud or rivet 14a of the touch contact 14. Since the pushbutton 11 is of an elongate web-like con struction (see Figure 2) the surface area available for its operation is larger than before and the push button 11 thus matches the shape and the cover of the light signal. This arrangement makes it possible to convert an existing non-push-button light switch into a push-button light switch simply by using the structural parts already available, it being merely necessary to insert the push-button or key device and to provide a socket support for the socket. WHAT WE CLAIM IS:

1. An electric push-button switch comprising a socket, a support member for the socket, a lamp in the socket, a cover, an area of the cover being capable of transmitting light from the lamp, a push-button passing through the cover spaced from the light transmitting area of the cover, said push-button having a depending push rod which is guided for movement between the socket and the support mem- ber, two electrical contacts on the socket which are enclosed by said support member, one of said contacts being engaged by the push rod and movable thereby to make or break electrical contact with the other one of said contacts when the push button is depressed and spring means for returning the push-button from the depressed position when the pushbutton is released.

2. A switch according to Claim 1, in which said one contact comprises a spring of angle shape.

3. A switch according to Claim 2, in which said other contact has an arm for electrical contact with said arm of angle shape.

4. A push-button switch for an electrical installation, substantially as hereinbefore described with reference to and as shown in the accompanying drawings.