US1760571A - Safety switch box - Google Patents

Description

May 27, 1930.

p. T. WADSWORTH 1,760,571

.SAFETY SWITCH BOX Filed Dec. 9, 1925 2 Sheets-Sheet 1 May 27, 1930. D. 'r. WADSWORTH SAFETY SWITCH BOX Filed Dec. 9, 1925 2 Sheets-Sheet 2 amulet Davi (1T Mdsugorfh, "1W

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Patented May 27, 1930 NITED stars DAVID T. WAIDSWORTH, OF GOLD SPRINGS, KENTUCKY, ASSIGNOR TO THE WADSWORTH ELECTRIC MANUFACTURING COMPANY, OF GUVIHGTON, KENTUCKY, A CORPORA- TION OF KENTUCKY SAFETY SWITCH BOX Application filed December This invention relates to safety switch boxes and has for an object the provision of a compact and inexpensive device.

Another object is to provide a device of the class described having a novel and simple mechanism for controlling access to the fuse chamber thereof and one which always bears a safety relation with the condition of the switch.

Another object is to provide a device of the kind referred to in which the switch control lever or crank constitutes a locking means for a sliding door for the fuse chamber.

Another object is to provide a device having the enumerated advantages in which there is embodied a sliding door control which is positive, simple and economical in material and labor.

These and other objects are attained by the means described herein and disclosed in the accompanying drawing, in which:

Fig. 1 is a fragmental perspective view of a device of my invention, showing a sliding door and switch operating handle in an operative position.

Fig. 2 is a similar view showing the sliding door and switch operating handle in an open position.

Fig. 3 is a fragmental side elevation, looking to the left of Fig. 2.

Fig. 4 is an enlarged fragmental cross section taken on line 4-4 of Fig. 1.

Fig. 5 is a cross sectional view taken on line 55 of Fig. 4, parts being broken away.

Fig. 6 is a front elevational view of a combined switch operating and door locking crank of my invention.

Fig. 7 is a view looking toward the left on Fig. 6.

A switch box or cabinet 10 is provided with a cover 11 which may be hingedly mounted thereon. The cover 11 has a suitable aperture 12 therein of such size and shape as to provide access to the fuse sockets 13 but to none of the other parts enclosed within the box. As

shown in the drawings, the fuse sockets may be disposed in a box like compartment 14 which separates them from the lead-in, load and test terminals, as well as the switch members. A slidable door l5is mounted for re- 9, 1325. Serial No. 74,418.

ciprocation upon the inner face of the cover 11 by means of flanged strips 16, the outer edges of which overhang the side edges of the slidable door. A suitable lug 17 is carried by one face of the slidable door 15 and extends through the aperture 12 thereby providing a simple means for manipulating said slidable door. The lug 17 may be perforated and a second perforate lug 18 mounted upon the cover 11 so that the fuse compartment may be locked against unauthorized access if desired. A notch 12 in the cover 11 accommodates lug 17 when the slidable door 15 is dropped to its lowermost limit of movement. The cover 11 maybe locked and sealed by means of a suitable latch member 170 engaging integral outwardly struck lug 180 carried by the side of the cover 11.

The locking means is provided for the slidable door 15 so as to render the fuse sockets inaccessible when the switch blades, such as 19, are in engagement with contacts 20'thereby closing a circuit controlled by the switch. The slidable door cannot be opened so long as the switch remains closed.

The means for accomplishing the locking of the slidable door and for providing the several safety features referred to, are embodied in a novel switch crank or throw lever shown in Figs. 6 and 7. The crank member, indicated generally by reference numeral 21, is economically formed of a single section of metal rod and comprises a handle portion 22 and bearing portions 23 and 24, adapted to pass through suitable perforations 25 in opposite side walls 26 of the box whereby the crank is mounted for rocking movement with handle portion 22 disposed exteriorly of said box. The bearing portion 24 isdisposed at one extreme end of the crank and is in longitudinal alignment with the bearing portion 23. Arms 26, 27 and 28 serve to position the switch rod29 and lock bar 80 in parallelism with the bearings 23 and 24 and in offset relation thereto. From the foregoing, it will be apparent that whenv the crank is moved about its pivotal mounting, the rod 29 and bar 30 will move through arcs described by arms 26 and 28 respectively. The switch blades 19 are connected to the switch rod 29 of flange 33 is by means of insulating members 31 suitably slotted at for receiving said rod. By referring to Figs. f and 7, it will be apparent that when the handle 22 is pulled forward (as in Fig. 2) the rod 29 will be raised to the position shown in full lines in Fig. 4, and bar 30 will assume a lowered position some what removed from the sliding door 15. The slidable door 15 carries a flange 33 which extends for a distance into the cabinet. lVhen the slidable door is in position for closing the aperture 12 i d cover 11, the lower end .sposed above lock bar 30 rank 21, which time the switch ades 19 engage contacts 20. At this time, e handle portion 22 assumes a vertical position. lVhen fuses are to be renewed or placed in fuse sockets 13, the handle 22 is pulled forward until it abuts a suitable stop such as 35 (see Fig. 3). This movement litits rod 29 through an arc and carries switch blade 19 clear of contacts 20. The switch is new open and the lock bar 30 has been moved arcuately downward and out of the path of the flange 33 on slidable door 15. The slidable door is now free to drop clear of aperture 12 so that the fuse sockets 13 are exposed.

Assuming now that the slidable door 15 is open ant. someone endeavors to close the switch, he will immediately find that the switch handle 22 cannot be moved, since, the lock bar 30 will strike the top edge of the flange 33. As soon as the door 15 is raised to completely close aperture 12, the handle 22 may be pushed back to a substantially vertical position (see Fig. 1) and rod 29 will carry the blades 19 into engagement with the contacts and at the same time, the lock bar 30 will assume a position as shown in dotted lines in Fig. 4, in abutment with the end 34 of flange 33, thereby precluding clownward movement of the slid able door.

Should the slidable door 15 be forced open without first having moved the switch handle to the open position, the end 34: of flange 33 will move the lock bar 30 and rod 29 so as to automatically open the switch.

Should an authorized person open the cover 11 and permit the slidable door 15 to drop, he will be unable to again close the cover 11 until the switch 192O is opened or door 15 is raised to a closed position. This feature makes it impossible to leave the box in an unsafe condition through inadvertence. Lihus the box when closed and sealed also precludes improper taking of the electric current from the fuse sockets 33 because, due to the interlocking relation of parts, the switch must be in the off position before the door 15 can be opened. The fuses are so connected as to be without current when the switch is open.

The mechanism just described eliminates the need of separate locking devices since the switch operating crank functions as a locking means as well as a switch operating means. This makes possible the provision of a more compact switch box structure and at the same time leaves the interior of the box conveniently accessible for authorized workmen.

WVhat I claim is:

1. In a device of the class described the combination with a switch box having an apertured cover, of a slidable door mounted for reciprocation upon the cover for opening and closing the aperture in said cover, a straight flange mounted on and terminating substantially within the body lines of the slidable door, a switch in the box, a crank journaled in the box for opening and closing the switch, said crank having an offset portion for movement into and out of the path of the flange as the switch is opened and closed by the crank.

2. In a device of the class described the combination of a switch box, an apertured cover for the box, a flanged door slidably mounted upon the cover for opening and closing the aperture in said cover, a pivotally mounted switch in the box and a crank comprising an integral rod journaled at the sides of the box and bent to provide a throw rod for moving the switch and a lock bar for movement into and out of the path of the flange on the sl-idable door, said lock bar being in substantial abutment with one end of the flange when the switch and door are closed.

3. In a device of the class described the com ation of a switch box comprising a cabinet, pivotally mounted switch blades and fuses within the cabinet, a flanged slidable door controlling access to the fuses and a crank pivotally mounted within the box and having an offset portion operatively connectcd with the switch and a second offset portion adapted to move into and out of the path. of the flange, movement of the crank in one direction serving to close the switch and lock the slidable door, and movement of said crank in the opposite direction serving to open the switch and permit opening of the slidable door whereby to render accessible the fuses in the cabinet, the flange on the door and the second mentioned ofl'set portion of the crank bearing such relation that forcible opening of the slidable door will move the crank about its pivotal mounting for opening the switches.

at. In a switch box structure a box having an apertured cover, a slidable door control.- ling the aperture in said cover, a straightedged flange on said cover, a switch, an externally operable crank for opening and closing the switch and having an integral offset portion adapted when the door is closed to abut the end of the flange, said offset portion being adapted, when the slidable door and switch are open to abut the edge of the flange ill) for precluding closing movement of the switch, and latching means for rigidly securing the apertured cover to the box to preclude opening of the cover by the crank.

5. In a switch box structure the combination of a box having an apertured cover, means for rigidly latching the cover to the box, a slidable door controlling the aperture in the cover, a straight-edged flange on said door and terminating Within the body lines of the door, a switch in the box, and an externally operable crank for the switch provided with an offset portion therein which when the switch and slidable door are open abuts the edge of the flange thereby precluding closing of the switch.

6. In a device of the class described the combination of a switch box having an apertured cover, a slidable door controlling the aperture in the cover, a depending straightedged flange on the door terminating substantially at the opposite ends of the door, a switch in the box and a manually operable crank for the switch having an ofiset portion thereon adapted to abut an end of the flange when the switch and door are closed.

7. In a device of the class described the combination of a switch box', an apertured cover for said box, a flanged slidable door for opening and closing the aperture in the cover, a movable switch member in the box and a switch operatingbail having an integeral bend therein constituting a lock bar for abutting an end of the flange on the slidable door when said door and switch member are in closed position.

8. In a device of the class described, the combination of a switch box having an apertured cover, a slidable door controlling the aperture in the cover, an angularly disposed fiange on the door with its ends substantially coincident with opposite ends of the door, a switch in the box and an operating bail with a bend therein for abutting one end of the flange when the door and switch are closed.

9. In a device of the class described the combination of a switch box having an apertured cover, a flanged slidable door controlling the aperture in the cover, a hingedly mounted switch member and an operating bail oscillatable in the box and having bent portion for throwing the switch memher and a second bent portion for abutting an of the flange when the door and switch are closed.

In testimony whereof, I have hereunto subscribed my name this 3rd day of December, 1925.

DAVID T. I/VADSWORTH.

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