US2047294A - Clamping device - Google Patents

Description

July 14, 1936. J. E. SIMEK CLAMPING DEVICE Filed June 28, 1935 INVENTOR. JOSEPH E. SIMBK.

A TTORNEY.

Patented July 14, 1936 UNITED STATES PATENT oFFIcE CLAMPING DEVICE. Joseph E. Simek, Omaha, Nebin.

Application: June 28, 1935, Serial No. 28,856: 4' Claims. (01. 247-21) This invention: relates to the art of clamping devices and particularly such clamping devices of the type disclosed in my'application fonpatent' flied January 28; 1935; Serial Number 32816, now

Patent No. 2,031,861, Feb; 25-,1'9'36,'ior use on electric switch boxes.

In its-preferred embodimentthe' invention is a device for attachment to swit'ch boxes and the like and particularly to switch boxes of 0011* venti'onal type and construction;

To fullyexplain the advantages of my invention I shall refer briefly to the construction and method of attachment of switch boxesnow in use.

Such boxes" are provided with an: outwardly ex'-- tending flange at each endsecuredto the box by suitable screws, said flanges being provided with screw holes in which are received screws for securing the boxtothe lath of a wall. The boxes are also provided with knock out portions which" 29" maybe knocked out to provide openings the box for conduits and wires. To adaptsuclr boxes for use with my clamping device; additional knock-out portionsareprovided oblong in shapeand extending parallel with the flangesand ad 5 jacent thereto. Such additional knock-outs in V volve but a nominal' increase in the cost of manu facturing the boxes. The boxesmay therefore be attached in the usual manner with screws-or the oblong knock-out portions may be removed and 30 my clamp attached andused in securing the box in a wall;

It is therefore the object of my invention to provide a clamp attachment forswitclr boxes that maybe attached thereto and used thereon without material alterations in construction, size,

shape,'or manufacture of switch boxes nowin-use;

Another object of my invention is to providea device that may be attached to substantially any type of switch box having the conventional 40 outwardly extending flange, and being provided with a suitable knock-out slot adjacent the flange.

Still another object isto provide a clamping device that may be set' to clamp the boxin' walls 01 various thickness, such as lath, lath and plaster, metal lath, or wall-board.

Further objects of my invention relate, to structural details for attaining simplicity of construction, durability, and inexpensiveness of manufacture.

Other objects will appear in the following detailed description taken in connection with the accompanying drawing wherein:

Figure 1 is a front elevation of my invention with the clamping member in its upward position.

Figure 2 is a side elevation of same.

Figure 3 is aplan view of same.

Figure 4 is airont elevation of my devicewith the clamping member in' its lower position,

Figure 5 is a side elevation of my device at 5' tached to aswitch box and clampingly receiving:

a lath between the clamping member and flange of the box;

Figure 6 is a plan view of the same, a portion of alath being shown in dotted lines. 10"

Figure '7 is a plan view of a modified embodi'-- ment of my invention.

Figure 8 is a partial vertical section through a switch box to which the modified embodimentshown in Figure 7 is attached, said view being 1& taken on line 8-8 of Figure 7;

Referring more particularly to the drawing, reference numeral I'O' indicates a substantially U-shap'ed plate having a downwardly extending, triangular ear or flange H to which a clamping 2o 7 member I2 is pivotally secured by arivet i3. The

provided with slotsfor a-djustably receiving screws 30' IT therein, said-screws being provided in the ends of' the box for securing the flanges thereto.

For use with my clamping device each end of the box is provided with a knockrout portion, oblong in shape, and when said knock-out por- 35- tions are removed, each end of the box is provided with an oblong slot [8 adjacent the respective'flange and extending parallel therewith.

To attach my clamping device to a box' end having the oblong knock-out portion, said knock- 40 out portion is removed, the screws l1 loosened and arms IQ of the U-shaped plate inserted beneath the horizontal portions lb of the flange l5,

7 and the length of the arms l9 and the depth of the slots in the horizontal portions l6 determine the amount of variation in the spacing the flange I5 and clamping member to each other, as well as their respective positions on the box.

For thin wall-board the flange and clamping member are set relatively close together but where it is desired or necessary to secure the box in a thick wall comprising lath, or lath and plaster, the flange I5 and clamping member I2 are spaced further apart to accommodate the lath or lath and plaster.

In attaching the box the clamping device is secured thereto with the clamping member in proper spaced relation to the flange I5. The clamping member is moved to a position inwardly of the box through slot I8, as shown in Figure 4. The box is then inserted in a wall-hole prepared for its reception and the clamping member I2 moved outwardly of the box to clamp lath 20 between said clamping member and flange I 5 as shown in Figure 5. By using a clamping device for each end of the box, said box is securely held in position in the wall.

Radially extending teeth 2| are peripherally provided on the clamping member and are adapted to permit the clamping member to be readily moved outwardly of the box, when clamping a lath or the like, but to resist movement in the opposite direction.

Should it be necessary to remove the box, the clamping member may be forced inwardly of the box, against the resistance of the teeth, a forwardly extending ear 22 being provided on the clamping member oppositely its pivotal axis. Preferably the clamping member is inclined slightly forwardly to cause the teeth to cut into the lath or wall-board and to produce a yielding pressure of the clamping member against said lath or wall-board.

The transversely extending portion of plate In is of suflicient width to close the rear part of the oblong slot I8 to prevent plaster or other foreign matter from entering the box at this point. Said transversely extending portion of the plate may also be provided with slots 23 extending forwardly from the rear edge thereof for receiving screws, as may be provided in some boxes, to attach the plate to the box.

The modified embodiment of my invention shown in Figures 7 and 8 is provided with a transversely extending plate IIO having an ear III to which a clamping member H2 is pivotally secured by a rivet II3. At one side of the plate I I is a longitudinally extending member I24 provided with a longitudinal slot I25 for adjustably receiving a screw I26 with which standard switch boxes are provided. At the opposite side of plate I ID a forwardly extending portion I 21 is provided, said portion I21 having an ear I28 turned under to slidably receive the adjacent box edge at the respective side of the slot I8. The ear I28 permits the plate II 0 to be slidably moved forwardly or rearwardly, provided the screw I26 has been loosened, but holds the plate end against upward movement.

In attaching the modified embodiment of my invention to a box the screw I26 is removed, the ear I28 inserted under the slot edge of the box and the screw replaced through the slot I25 in the longitudinally extending member I24. The clamping device is adjusted on the box relative to the flange I and the screw tightened. The box is clamped to lath or wall-board or the like in the same manner as is the preferred embodiment of my invention.

While I have shown my invention in combination with a switch box it is to be understood that it may be used on other types of boxes or on frames having flanges and slots in suitable association.

Having thus described my invention what I claim is:

1. The combination of a switch box having an outwardly extending flange and an opening therein adjacent to and parallel with said flange, with a clamping device comprising a plate secured to said box above the opening therein, a flange on said plate extending inwardly of the opening in a plane parallel with the outwardly extending flange of the box, and a clamp member pivotally mounted on the inwardly extending flange and adapted to be moved pivotally through the opening in the box in spaced relation with the outwardly extending flange.

2. The combination of a switch box having an outwardly extending flange and a slot therein adjacent to and parallel with said flange, with a clamping device comprising a plate having a pair of longitudinally spaced parallel arms extending laterally from one side thereof, a flange on the plate on the side having the arms, said flange being at substantially right angles to the plate and extending longitudinally thereof between the arms and extending inwardly through the slot in the box, a disk eccentrically pivoted to the flange, teeth on the side of the disk facing the outwardly extending flange on the box and pointed in one direction of movement of said disk to permit the clamp member to be readily moved into clamping association with the outwardly extending flange of the box and to resist movement of the clamp member in the opposite direction, said disk being movable through the slot, and means for securing the arms to the box.

3. The combination of a switch box having an outwardly extending flange and a slot therein adjacent to and parallel with said flange, with a clamping device comprising a plate, means for adjustably securing the plate to the box relative to the outwardly extending flange, said plate being above the slot, a flange on the plate extending inwardly of the slot in a plane substantially parallel with the outwardly extending flange of the box, and a disk eccentrically pivoted to the inwardly extending flange of the plate and adapted to be moved pivotally through the slot in spaced relation with the outwardly extending flange of said box.

4. A structure as set forth in claim 3 including teeth on the disk on the side thereof facing the outwardly extending flange of the box, said teeth being pointed in one direction of movement of the disk.

JOSEPH E. SIMEK.

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