US3457381A - Interlock between switch and cable connector for electrical apparatus - Google Patents

Description

July 22, 1969 w. A. M MORRIS 3,457,381 INTERLOCK BETWEEN SWITCH AND CABLE CONNECTOR FOR ELECTRICAL APPARATUS Filed March 21, 1967 United States Patent US. Cl. 200-50 2 Claims ABSTRACT OF THE DISCLOSURE An interlock between a switch and cable connector to prevent removal of the cable connector when the switch is in closed position. A switch handle is located on the exterior of an electrical apparatus and the cable connector is similarly mounted near the switch handle. The cable connector is provided with a clamping device which rotates between an unlocked position to a locked position in which it engages a pair of lugs on the exterior of the electrical apparatus. When the clamping device is in its locked position, the switch handle will be in interference contact with the clamping device when the switch is closed, preventing movement of the clamping device to the unlocked position.

Background of invention This invention relates to interlocks and more particularly, to an interlock between a switch and a cable connector for use in electrical apparatus.

There is presently a well-defined, growing trend in electrical distribution from overhead, open wire electrical distribution to underground, buried wire distribution. With this growing trend, many utilities are evolving new operating procedures to develop safe, efiicient operating practices for underground servicing. At the same time, equipment manufacturers are attempting to build distribution equipment which may be used with these new operating procedures. Many types of distribution apparatus are now provided with plug-in cable connectors which may be removed by the lineman when servicing the equipment. The removal of the connector provides a positive, visually verifiable opening of the circuit to or from the electrical apparatus. While many of these connectors are provided with design capabiilty of interrupting current when unplugged or disconnected, many utilities prefer, for safety reasons, to electrically open the cir cuit before the connector is removed. To provide this desirable open circuit feature, many types of electrical apparatus using plug-in cable connectors are also provided with switching means to open the circuit from the apparatus to the cable before the cable connector is removed. In order to be sure that the switch is in open circuit position before disconnecting the cable, it is believed desirable to provide an interlock between such cable and connector.

It is therefore, one object of this invention to provide a novel interlock between a cable connector and a switch of an electrical apparatus to prevent removal of the cable while the switch is in the closed position.

A further object of this invention is to provide a novel interlock using the cable connector locking device in conjunction with the switch handle.

Summary of invention Briefly, in one form, the interlock of this invention comprises a cable connector removably mounted on an electrical apparatus and having a rotatable clamping ring for locking the cable connector to a pair of lugs on the electrical apparatus, when the clamping ring is rotated to a locked position. A switch operating member is also mounted on the electrical apparatus and movable between a switch opened and a switch closed position. When the switch operating member is in the switch closed position, it has a portion in interference contact with the clamping ring when the clamping ring is in locked position preventing rotation of the clamping ring.

The invention which is sought to be protected will be particularly pointed out and distinctly claimed in the claims appended hereto. However, it is believed that this invention and the manner in which its various objects and advantages are obtained, as well as other objects and advantages thereof, will be better understood from the following detailed description of a preferred embodiment thereof, particularly when considered in the light of the accompanying drawing.

Brief description of drawing FIGURE 1 is a perspective view of one form of interlock between a cable connector and a switch according to this invention;

FIGURE 2 is a top view of a modified form of interlock, similar to that shown in FIGURE 1, partially in section and with parts eliminated to more clearly show the operation of the interlock;

FIGURE 3 is an exploded view of the portion of the interlock relating to the cable connector;

FIGURE 4 is a detailed sectional view of one portion of the interlock of the cable connector; and

FIGURE 5 is a side view of one of the locking lugs showing a preferred form thereof.

escription of preferred embodiment This invention relates to an interlocking means between a switch and a cable connector in which the switch operating mechanism is in interfering relation with the clamping device of the cable connector, when the switch is in closed position. The preferred embodiment set forth herein discloses the present specific construction believed most suitable for obtaining its various objects and advantages. Obviously, changes may be made in various structural details without departing from the scope of the defined invention.

Referring now to the drawing in which like numerals are used to indicate like parts throughout and referring particularly to FIGURE 1, the preferred form of interlock of this invention is shown as applied to an L-shaped cable connector 10 which is connected to a stud or bushing member (not shown) mounted on a wall portion or cover 12 or an electrical apparatus, such as, for example a distribution transformer. As will be understood, the stud or bushing (not shown) is connected to the electrical element of the apparatus and receives electrical power from the cable connector 10. Cable connector 10 is provided with a flanged member 14 on the lower part thereof as shown. The flange member 14 is secured to cable connector 10 by a bail 16. Rotatably mounted on flange member 14 is a ring member 18 which is the clamping ring to secure cable connector 10 to the stud of the electrical apparatus.

As can be seen from FIGURE 1, clamping ring 18 rides on the flange 20 of flange member 14 and engages a pair of lugs 22, 24 when in the clamped or locked position shown. A handle portion 26 is provided on the clamping ring 18 having an opening 28 to enable operation of the clamping ring 18 by means of a hook stick or the like, as will be readily understood. The handle portion 26 also locks or clamps under the lug 24 as shown. In a similar manner, the opposite side of clamping ring 18 has a locking portion 30 which hooks or clamps under the lug 22. Thus clamping ring 18 may be rotated on flange 20 of-the flange member 14 to lock or clamp the cable connector in the position as is shown. Bail 16 is also provided with an opening 32 to enable the cable connector 10 to be placed on or removed from the bushing (not shown) on wall portion or cover member 12 of the electrical apparatus. As will be understood, a hook stick or similar tool may engage bail 16 through opening 32 to enable cable connector 10 to be removed from or placed on the stud or bushing of the electrical apparatus.

The relationship of flange member 14, bail 16 and clamping ring 18 are best shown in the exploded perspective view of FIGURE 3. As is shown, flange member 14 has a flange 20 and slots 34, only one of which is shown, on the opposite sides thereof. The ball member 16 has hooked portions 36 which hook into the slots 34, in the manner best shown in FIGURE 4. Bail 16 is also provided with a slide member 38 which cooperates with a raised portion 40 on cable connector 10 to secure bail 16 to cable connector 10, as is best shown in FIGURE 1. It will of course, be apparent that the slide member 38 could be readily fastened by rivets or other means to the portion 40 of cable connector 10 if desired. Further, it will be understood that flange member 14 may contact raised members, such as member 42 on the lower portion of the cable connector 10, or it may be of sufficient length to meet the enlarged portion 44 of cable connector 10. As will be understood, bail member 16 securely holds the flange member 14 on the lower portion of the cable connector 10 such that the clamping ring 18 may lock the cable connector 10 to the wall portion or cover member 12 of the electrical apparatus. However, to enable the opening 32 of bail member 16 to be used to remove the cable connector from the wall portion or cover 12 of the electrical apparatus it is necessary that the flange member 14 be mounted such that it cannot ride up to any extent on the lower portion of cable connector 10.

The log members 22 and 24 are mounted on the wall or cover 12 of the electrical apparatus in any desired manner, a weldment being shown at 46 in FIGURE 1. In the preferred form, the lugs 22 and 24 are L-shaped with one portion of the L being welded or otherwise secured to the wall portion or cover member 12, as is shown. The preferred shape of lug members 22 and 24 is best shown in FIGURE 5. As can be seen from FIGURE 5, the open end of the L-shaped lug member 24 is provided with a tapered portion 48 which tapers toward the open portion of the lug member. As will be understood, as the clamping ring 18 is turned under lug members 22 and 24, the handle 26 and the locking extension will contact the tapered portion 48 and slide the handle 26 and locking portion 30 down under the open portion of lugs 22 and 24, thus securely tightening the cable connector 10 to the stud or bushing (not shown) which is mounted on the wall member or cover 12.

Also provided on wall member or cover 12 is a switch handle 50 which is provided with an opening 52 which may be used with a hook stick or the like for opening and closing the switch member 50. As will be understood, the switch member 50 is the operating member or handle for a switch which is located within the electrical apparatus below the wall portion or cover member 12. Operation of the switch member 50 will open or close the switch within the electrical apparatus in a manner which is well understood by those skilled in the art. This opening and closing as mentioned can be performed by a hook stick or the like which is hooked into the opening 52 of the switch member 50.

FIGURE 1 shows one form of switch handle 50 which may be used with the interlock of this invention, while FIGURE 2 shows a modified form of switch handle 50; equally useful in this invention.

As is shown in FIGURE 1, switch member 50 is movably mounted on Wall portion or cover member 12 in the vicinity of the cable connector 10. As will be obvious, the switch member 50 movable between an open and a closed position. In the open position, as shown in FIG- URE l, the switch member 50 does not interfere with the clamping ring 18, such that the clamping ring may be readily rotated about flange 20 of flange member 14 to unclamp or unlock the cable connector 10 from the lugs 22, 24 on the wall portion or cover member 12. However, when the switch member 50 is moved to its closed position, as will be apparent, an extended portion 54 having a locking notch 56 will move into interfering contact or position with the locking portion 30 of clamping ring 18. This portion is best shown in the modified form of interlock shown in FIGURE 2 of the drawing.

Referring now to FIGURE 2, which is a top view of the interlock with a portion of the flange member 14 in section, and the cable connector 10 eliminated, it can be seen that with the clamping ring 18 in locked position under lugs 22 and 24, that the locking portion 3 0 of the clamping ring 18 is in interfering position with portion 56' of switch member 50 when the switch member is in the closed position as is shown in FIGURE 2. Of course, it will be apparent to those skilled in the art, that the switch member 50 may be provided with the extension 56' which will provide interference contact with the locking portion 30 of clamping member 18. However, if desired, the notched portion 56, shown in FIGURE 1, may be provided on the extending portion 54 of switch member 50. Notch 56 may make contact with the extended locking portion 30 of clamping ring 18 thereby allowing the top part 54 of the extension of handle 50 to cover the remainder of the locking member 30. Obviously, in either case, the notch 56 or portion 56' will provide an interference contact with the locking portion 30 of clamping ring 18, preventing the clamping ring from being moved to an unlocked position when the switch member 50 or 50" is in the closed position. As switch member 50 or 50 is moved to the open position, which is best shown in FIG- URE 1, the interference contact is removed, thereby a1- lowing clamping member 18 to be rotated to be disengaged from the lugs 22, 24 to allow removal of the connector 10. When a locking notch 56 is used, as in FIG- URE 1, it may be desirable to provide a cut-out portion tion 58 to prevent interference between handle 50 and locking portion 30 When the handle 50 is rotated to open position.

While there have been shown and described the present preferred embodiment of the invention, it will be apparent to those skilled in the art that various changes may be made in constructional details without departing from the spirit and scope of the invention, particularly as it is defined in the appended claims.

What is claimed as new and which it is desired to secure by Letters Patent of the United States is:

1. An interlock between a switch and cable connector for an electrical apparatus comprising:

(a) a fixed portion of the electrical apparatus,

(b) a movable switch handle mounted on the exterior of said fixed portion,

(0) a removable cable connector mounted on the exterior of said fixed portion in the vicinity of said switch handle,

(1) a flange member secured to said cable connector,

(2) a clamping ring rotatably mounted on the flange of said flange member,

(3) a bail member connected to said cable connector and to said flange member for securing said flange member to said cable connector,

(d) a pair of upstanding locking lugs secured to said fixed portion in locking position with respect to said clamping ring whereby when said clamping ring is in a first position, it is free of said lugs and when rotated to a second position, said clamping ring locks with said lugs,

and said switch handle movable to two positions, said switch handle when in a first position preventing said clamping ring from moving from said second to said first position and when said switch handle is in a second position, allowing said clamping ring to move from said second to said first position.

2. An interlock between a switch and cable connector for an electrical apparatus comprising:

(a) a fixed portion of the electrical apparatus,

(b) a movable switch handle mounted on the exterior of said fixed portion,

(c) a removable cable connector mounted on the exterior of said fixed portion in the vicinity of said switch handle,

(1) a flange member secured to said cable connector,

(2) a clamping ring rotatably mounted on the flange of said flange member,

(d) a pair of upstanding locking lugs secured to said fixed portion in locking position with respect to said clamping ring whereby when said clamping ring is in a first position, it is free of said lugs and when rotated to a second position, said clamping ring locks with said lugs,

and said switch handle movable to two positions, said switch handle when in a first position preventing said clamping ring from moving from said second to said first position and when said switch handle is in a second position, allowing said clamping ring to move from said second to said first position, and said clamping ring having a portion extending beyond said locking lugs, said extending portion being in interfering relation with said switch handle when said clamping ring is in said second position and said switch handle is in said first position.

References Cited UNITED STATES PATENTS 2,397,595 4/1946 Conlan ZOO-50.2

ROBERT K. SCI-IAEFER, Primary Examiner ROBERT A. VANDERHYE, Assistant Examiner US. Cl. X.R. 200-51

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