US1914493A - Electrical switch - Google Patents

Description

June 20,- 1933. E. R. EVANS ELECTRICAL SWITCH Filed May 1, 1930 I m I I Patented June. 20, 1933 Pars EARL B. EVANS, OF WASHINGTON, DISTRICT OF COLUMBIA ELECTRICAL SWITCH Application filed May 1, 1930. Serial No. 448,960.

My invention relates to electrical switches and more particularly to manually-operated enclosed switches.

One obj ect of my invention is to provide a switch adapted for use as a wall swltch but having no projecting levers or actuating buttons as in the ordinary wall switch.

Another object of my invention is to provide a switch having a flexible or deformable cover plate operatively connected to contact or circuit-closing mechanism of the mercury 3r liquid-flow type.

A further object of my invention is to provide a wall switch of improved constructlon embodying a tight, dust-proof casing of attractive appearance.

A. still further object of my invention is to provide an improved switch of the liquidcontact type.

A switch embodying the invention is illustrated by way of example in-the accompanying drawing, in which Fig. 1 is a front view of a switch of the wall type;

Fig. 2 is a sectional view on the line 22 of Fig. 3; and i Fig. 3 is a front View of the switch with the cover plate removed.

The wall switch shown in the drawing comprises a box 1, of porcelain or the like, which is closed by a cover plate 2 of metal, bakelite or other suitable material. The cover plate 2 is preferably imperforate or substantially imperforate and forms with the box 1 a tight, dust-proof container for the switch mechanism. The cover plate 2 is also flexible or deformable and is arranged to cooperate with the switch mechanism to operate the same upon fleXure of the cover plate, as indicated in dotted lines in Fig. 2. An integral button portion 3 may be formed in the cover plate 2, as shown, to indicate the point at which pressure should be applied to actuate the switch.

The boX 1 is provided with a liner 4 to which the cover plate 2 is secured by screws 5. Various other means may be employed for holding the casing, switch mechanism and cover plate in assembled relation without departing from the scope of the invention.

The preferred switch mechanism embodies a mercury contactor 10 of the liquidflow type in order to provide noiseless operation and obtain mechanical simplicity; although any suitable or usual switch mechanism may be employed. The mercury contactor 10 is of the usual construction and embodies a tube of vitreous material con taining contacts adapted to be bridged by a body of mercury or other liquid conductor, the tube being pivoted upon the projecting lugs 11 and 12 of the lining 4. The tube 10 is preferably encircled by a clamping band or ring 13 having projecting pivotal pins 14 engaging the lugs 11 and 12. The clamping band 13 is further provided with integral cam members 15 and 16 adapted to cooperate with the actuating member 17, and is held in position by the screw or bolt 18. The actuating member 17 is secured to the cover plate 3 and is adapted to engage the cam members 15 and 16 to open and close the circuit including conductors 2O alternately upon successive depressions of the cover plate, the weight of the mercury in the tube 10 tending to hold the contactor in its actuated position in each instance.

The cover plate 2 may be either fiat or of any desired configuration and size, provided a portion thereof may be flexed or deformed to actuate the switch mechanism. Since no projecting buttons. or toggle levers are employed, the switch is attractive in appear ance and may be colored or ornamented to conform to the wall decoration where it is used. The use of liquid-contact switch mechanism is preferred because of the small energy required to operate such mechanism and because of its noiseless operation. Various modifications in the structure of the respective elements of the switch described and shown herein and in the connection between the cover plate and contactor particularly, may be made without departing from the scope of the invention as defined in the appended claims.

What I claim is:

1. An enclosed electrical switch embodying a box-like enclosure of insulating material, a flexible substantially imperforate plate member in front of the enclosure for said switch,'a switch element of the liquidflow type pivoted adjacent said plate member and means for operating said switch element in response to the flexure of said plate.

2. An electrical switch embodying a hollow enclosure, a thin imperforate cover plate therefor, a tiltable mercury switch element and means cooperating with said cover plate and switch element to open and close the circuit alternately upon successive depressions of the cover plate.

3. An electrical switch embodying a casing and a tiltable mercury contact device in said casing, the casing including a yielding plate member provided with cam operating means for tilting the contact device.

4. An enclosed switch having a casing provided with a deformable wall, a tiltable mercury contactor in said casing and means for tilting said contactor to operate the same upon deformation of said wall.

5. A wall switch comprising a casing adapted to be mounted in a wall, an imperforate front cover-plate secured thereto, said cover-plate being so thin that it is read: ily deformable by the pressure of the fingers, a movable switch element of the liquid-flow type mounted in said casing and means cooperating with said switch element for actuating the same upon a movement of aportion of the cover-plate.

6. A wall switch comprising a casing adapted to be mounted in a wall, a front cover-plate of thin, flexible insulating material secured thereto and switching means of the liquid-flow type in said casing operatively associated with said cover-plate.

7. A wall switch comprising a hollow insulating enclosure adapted to be mounted in a wall, a front cover-plate therefor of thin, flexible material, a switch-operating member projecting from the back of said coverplate and operated by flexure of said coverplate, and switching means of the liquidflow type in said enclosure in the path of movement of said switch-operating member to be actuated thereby.

In testimony whereof I aflix my signature.

EARL R. EVANS.

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