US2264720A - Safety switch - Google Patents

Description

Dec. 2, 1941. J. w. SAMZELIUS SAFETY SWITCH Filed April 27, 1940 WITNESSES:

John W. ScwzzeZz'z/s.

Patented Dec. 2, 1941 UNiTED SAFETY SWITCH Pennsylvania Application April 27, 1940, SerialNo. 332,045

Claims.

In safety switches of some types, the switch blades are actuated by a one-piece crank and operating handle, the crank portion being disposed inside of the cabinet and the handle portion on the outside. In the past, the usual practice has been to insert the crank by snaking the bends through a hole in the side of the cabinet. Such a method is not entirely satisfactory because of the time required to make the assembly and also because of the fact that the hole in the handle side of the box must be larger than is desirable to make a good bearing for the crank.

An object of my invention, generally stated, is to provide a safety switch which shall be simple and efficient in operation and which may be economically manufactured and installed.

A more specific object of my invention is to simplify the assembling of a one-piece crank and operating handle in a safety switch cabinet.

Another object of my invention is to provide a combined mounting for the crank and latch for the cover of a safety switch cabinet.

A further object of my invention is to provide a relatively tight cabinet for an electric switch.

Still another object of my invention is to provide a combined bearing plate and stop member for the crank and handle of a safety switch.

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

In accordance with my invention, a relatively deep slot, into which the crank is dropped, is provided in the handle side of a safety switch cabinet. The side wall is slit at right angles to the slot at two places on each side of the slot and the portions between these slits are bent inwardly in a short S-bend to form guides for a spring steel strip having a slot for the crank near one end and a catch for the lid near the other end, which is hooked over the crank and pushed downwardly in the guides as the crank goes down into the slot in the side wall of the cabinet.

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

Fig. 1 is a view, in side elevation, of a safety switch cabinet embodying my invention, a portion of the cover being broken away for clearness;

Fig. 2 is a sectional view, taken along the line II--II of Fig. 1;

Fig. 3 is a view, in side elevation, of a portion of a side wall of the cabinet shown in Fig. 1;

Fig. 4 is a view, in elevation, of a combined latch and crank mounting utilized in the structure shown in Fig. 1; and

Fig. 5 is a View, in perspective, of a combined stop and bearing plate also utilized in the cabinet structure.

Referring to the drawing, and particularly to Fig. 1, the structure shown therein comprises a cabinet It for enclosing a switch mechanism (not shown). Thecabinet It is provided with a cover II which may be hinged to the cabinet at one side in the usual manner.

In accordance with the usual practice, a onepiece operating crank 12 having a handle .portion I3 disposed exteriorly of the cabinet is provided for actuating the switch mechanism. As explained hereinbefore, the usual practice has been to mount the operating crank I 2 in holes provided in opposite side walls of the cabinet Iii, the side walls thereby supporting the operating crank and serving as bearings for the crank member. However, as explained hereinbefore, considerable difiiculty is usually experienced in assembling the crank member in the cabinet unless one of the holes is made considerably larger in diameter than the crank, in which case it does not provide a suitable bearing for the crank.

In order to overcome the foregoing difiiculty, I have provided a slot I4 in one side wall of the cabinet H3. The slot I4 is approximately the same width as the diameter of the crank and a bearing aperture I5 is provided at the bottom of the slot.

As shown in Fig. 3, two slits 5 are made in the side wall on each side of the slot M at right angles to the slot and, as shown in Fig. 2, the material between each pair of slits is bent inwardly in a short S-bend to form guide mem! bers H.

A latching strip 18, which is preferably comprised of spring steel and is of suificient width to cover the slot i4, is disposed between the guide members I! and the inside of the side wall of the cabinet 1'0. As shown in Fig. 4, the strip 18 is preferably provided with a slot [9 in one side near the lower end of the strip. The slot I9 is approximately the same width as the diameter of the crank l2 and a bearing aperture 2! is provided at the bottom of the slot l9. If desired,

the slot I9 may be vertically disposed in the bottom end of the strip 18, or a hole hold of sufficient diameter to permit the strip to be threaded over the crank, may be utilized. However, the structure shown in the drawing is preferable for assembly purposes, as will be explained more fully hereinafter.

The strip I 8 is of sufficient length to extend through a suitable slot 22 in the cover H and is provided with a barb 23 for engaging the cover to retain it in the closed position on the cabinet. Since the strip is preferably comprised of spring steel, the catch 23 may be easily released from the cover by pressing on the upper end of the strip.

In order to assemble the crank [2 in the cabinet, it is merely necessary to hook the slot l9 over the crank I2 and start the strip 18 between the guide members I! and the inside of the cabinet wall. The strip may then be forced downwardly between the guides by pressing down on the handle portion 13 of the crank [2. It will be seen that the strip I8 not only closes the slot M to form a relatively tight cabinet, but also provides a bearing surface for the crank I2 since the apertures l5 and 2| are concentrically disposed when the crank is in its operating position. Furthermore, the strip l8 functions as a latch for retaining the cover in the closed position and since the strip is made separately from the remainder of the cabinet, it may be composed of a high grade of spring steel, thereby providing an efficient latch member.

In order to fasten the strip I8 and the operating crank in position, a pair of holes 24 are provided in the strip 18 and material may be forced from the side wall of the cabinet into these holes by means of a center punch or other suitable tool. If desired, the strip may be secured in position by spot welding or methods.

If it is desired to provide additional bearing surface for the crank l2, a bearing plate 25 may be secured to the outside of the side wall of the cabinet. As shown in Fig. 5, the bearing plate 25 is provided with a bearing aperture 26 which is concentric with the apertures l5 and 2! when the plate is secured to the cabinet as shown in Fig. l. The plate 25 may be secured to the cabinet by spot welding or by screws or rivets inserted in holes 21 provided in the bearing plate.

In order that the handle portion l3 of the operating crank shall be stopped at predetermined position, namely, the off and on positions of the switch mechanism, ears 28 are provided on the bearing plate. As shown, the ears 28 are perpendicular to the surface of the cabinet side wall and are so disposed that they stop the movement of the handle at the desired positions. A hole 29 is provided in each one of the ears 28 to permit a padlock or other suitable locking device to be utilized for locking the handle [3 in either the oif or the on position. A hole 3| may be provided near the top of the latching strip I8 to perother well-known mit the cover II to be locked in the closed position, if desired.

From the foregoing description, it is apparent that I have provided a safety switch cabinet which may be manufactured economically and which greatly facilitates the assembly of the switch structure and its operating mechanism. Furthermore, the cabinet is relatively tight in construction, thereby excluding dirt and moisture from the cabinet as well as reducing the fire hazard caused by arcs drawn on the inside of the cabinet.

Since numerous changes may be made in the above described 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 drawing, shall be interpreted as illustrative and not in a limiting sense.

I claim as my invention:

1. In an enclosed switch structure, in combination, a switch cabinet having a slot in one side wall thereof, a switch actuating member disposed in the slot, guide members formed integrally with said side wall, and means disposed in said guide members for covering said slot and retaining said actuating member at the bottom of said slot.

2. In an enclosed switch structure, in combina tion, a switch cabinet having a slot in one side wall thereof, a switch actuating member disposed in the slot, a guide member formed integrally with said side wall at each side of said slot, and means disposed between said guide members for covering said slot and retaining said actuating member at the bottom of said slot.

3. The combination with a switch cabinet having an openable cover and an actuating crank, of a spring strip having a bearing aperture therein for the crank and a catch thereon for releasably latching the cover on the cabinet, and guide means for said strip formed integrally with the cabinet.

4:. The combination with a switch cabinet having an openable cover and an actuating crank, of a spring strip having a bearing aperture therein for the crank and a catch thereon for releasably latching the cover on the cabinet, guide means for said strip formed integrally with the cabinet, and means for securing said strip to the cabinet thereby retaining the crank in it operating position.

5. In a switch cabinet having an openable cover and a slot in one side wall, in combination, a one-piece operating crank disposed in said slot, a resilient strip having a bearing aperture therein for the crank and a catch thereon for releasably latching the cover on the cabinet, said strip being disposed to substantially close said slot, and a bearing plate secured to the cabinet and having stops thereon for engaging said crank in predetermined positions.

JOHN \V. 'SAMZELIUS.

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