US2242271A - Connecting device - Google Patents

Description

May 20, 1941.

B. E. SPIRO CONNECTING DEVICE Filed May 11, 1940 VIIII/I/II/I/l/II/A minim /7 Inventor: Benjamin E. Spiro,

is Attorn ey.

Patented May 20, 1941 CONNECTING DEVICE Benjamin E. Spiro, Philadelphia, Pa., assignor to General Electric Company, a corporation of New York Application May 11, 1940, Serial No. 334,567

8 Claims.

My invention relates to improvements in connecting devices for conducting electric currents and more particularly to connecting devices which are readily operable to establish and disestablish acurrent conducting connection between two spaced conductors. The principal object of my invention is to provide an easily and quickly operable connecting device which has a relatively simple and economical structure requiring a minimum of space and providing a maximum of assured conductivity even under heavy currents. This and other objects of my invention will hereinafter appear in more detail.

In the so-called low voltage alternating current networks or distribution systems, it is customary to use devices known as network protectors. These embody a circuit interrupting unit, such as a circuit breaker, which is connected in the lines to the network on the low voltage side of a transformer whose high voltage winding is connected in the high voltage feeder. This circuit breaker is used to open the lines to the network load under predetermined conditions. In order to provide backup protection in case the circuit breaker fails to clear a fault on the high voltage side of the network, fuses are provided in the low voltage lines between the network and the circuit breaker terminal adjacent the network. By removal of these fuses the network protector may be isolated from the low voltage network. However, certain parts of the protector including control circuits, electrical actuating means, the circuit breaker movable contacts, and other parts, remain electrically connected to the transformer. Obviously these parts of the protector will be alive as long as the transformer is energized. Since it is sometimes desirable or necessary to make adjustments or repairs on installed protectors, it is important that such work may be done with safety and dispatch under' the most favorable working conditions possible. This means that the protector must be isolated from both the high and low voltage sides of the distribution system.

In accordance with my invention, I provide a readily operable connecting means which may be inserted in the low voltage lines between the low voltage side of the distribution transformer and the protector. Also, in accordance with my invention, I provide a safe and simple means whereby this connector may be operated to dis-establish the circuit between the protector and the transformer on the low voltage side thereof even though certain parts of the protector are alive. Since these network protectors are usually installed in locations where space is a controlling factor, I provide, in accordance with my invention, a connecting means which requires a minimum amount of space and yet provides ample current conducting capacity even under overload conditions without reduction of such capacity in consequence of any magnetic effects attendant upon such heavy currents. Further, in accordance with my invention, I provide a connecting means such that the whole protector unit may be withdrawn from or returned to its enclosing case in the event that adjustments or repairs are too extensive to make in the field or further to allow a ready substitution of one protector unit for another.

My invention will be better understood from the following description when considered in connection with the accompanying sheet of drawings, and its scope will be pointed out in the appended claims.

Fig. 1 illustrates in perspective, with parts broken away for clearness, a connecting device embodying my invention and shown in the connecting position; Fig. 2 is a sectional view on a plane through the lines 2-2 of Fig. 1 looking in the direction of the arrows touching these lines; Fig. 3 is a sectional view on the line 33 of Fig. 2 looking in the direction shown by the arrows with the connecting device in the disconnecting position; and Fig. 4 is a circuit diagram illustrating an application of my invention to a low voltage alternating current network.

As shown in the drawing, I provide means for establishing a current conducting connection between the ends of two spaced conductors 6 and I which, as shown, are tubular members of rectangular shape since these are particularly useful in network protector units to obtain desired cooling effects. It will be obvious to those skilled in the art that the conductors 6 and I may be tubular members having other shapes, flat bus bars and the like or anything else suitable for the purpose of conducting the desired currents. While I have shown the corresponding faces of the conductors 6 and I substantially coplanar, this is not essential to the carrying out of my invention, as will hereinafter be obvious. As illustrated, my current conducting connection comprises two connecting elements, such as a bridging contact 8 and a second bridging contact which, in order to allow for inaccuracies in alignment of the conductors 6 and 1, may comprise a plurality of bridging elements 9, l0 and II. In order that the bridging elements 9,10 and II may be operated as a unit, I provide a support, such as a backing plate IE, to which the contacts 9, Hi and H are secured by suitable means, such as screws [3 so that these contacts may move relatively to each other and to the backing plate. For this purpose the plate 52 is slidably mounted on the screWs 13 which are bottomed in the bridging contacts 9, is and I l and suitable resilient means, such as spring washers i i, are provided between the plate [2 and the bridging contacts. These resilient means may be mounted on the screws, as shown.

In accordance with my invention, I provide means for supporting the bridging contacts 3, 3, I and H on one of the conductors, such as 'l, for transl-atory movement in line with the ends of the conductors. Further, in accordance with my invention, this means is rotatably mounted: on the conductor and extends across the space between the ends of the conductors 6 and l andis of a character to eifect translatory movement from rotary movement. As shown, this rotatable means comprises a shaft which is journaled in the bridging contact 8, the bridging contact it! and the backing plate 12 and is retained in place by suitable means such as a washer 4 and cotter pin 5. For efiecting translatory movement in consequence of rotary movement of the shaft 15, I provide thereon a suitable cam is which, as illustrated, is of cylindrical form eccentrically supported on and rotatable with the shaft. For supporting the cam on the conductor i in order to obtain the desired movement, the supporting means, which I provide, comprises top and bottom yoke members i1 and I8, respectively, which are suitably secured to the conductor 1 as by screw members l9. In order to limit the angular movement of the cam. l6 so as definitely to position the bridging contacts across the ends of the conductors 6 and I and to lower the contacts to the position shown in Fig. 3, the yoke members I"! and I8 may be provided with suitable openings 2%] and 2| which, in the construction shown, permit a half revolution of the cam by acting as abutments for a projection on the cam, such as a pin 22, which may also serve to secure the cam to the shaft 15.

Further, in accordance with my invention, I provide means for moving the bridging contacts 8, 9, l0 and H lengthwise of the shaft I5 so as to move the contacts toward and away from the conductors 6 and l and also to hold the contacts in position against these conductors. As shown, these means are bolt members, such as screws 23, which turn freely in the backing plate I2 and the bridging contacts 9 and I I but engage cooperating threads in the bridging contact 8. In order to maintain the bridging contacts in substantial alignment with the ends of the conductors G and l, the screws 23 are arranged to be guided by the Vertical sides of the yoke member I1. As shown more clearly in Fig. 2, the sides of the yoke member ii are slightly inclined towards each other but provide an inside width across the top equal to the distance. across the outsides of the screws 23 so as to insure the corvrect alignment of the bridging contacts when they are to be moved to the current conducting position. With the sides of the yoke ii inclined, as shown, so as to be wider at the bottom, any friction or binding in the lowering of the bridging contacts to the position shown in Fig. 3 is substantially eliminated.

Since for disconnectin purposes the screws 23 are only to be locsenedand not removed, I provide means for preventing unintentional with-- drawal of these screws in order that the guiding effect of the yoke I! may not be lost and also that the screws themselves may not be lost or fall onto conducting parts with the possibilities of causing short-circuits or dropping into operating mechanism to jam the same. As illustrated, this means comprises the retaining washer 23 which may be held in place on the threaded end of the screw 23 outside of the bridging contact 8 by any suitable means, such as a cotter pin 24.

Assuming the parts positioned, as shown in Fig. 1 and that it is desired to isolate one of the conductors 6 from the other conductor 7, then a suitably insulated wrench, examples of which are well known to the art, is used to back off the screws 23 whereby to release the pressure of the contacts 8, 9, I0 and II against the conductors 6 and I. The wrench is then applied to the bolt headed end of the shaft l5 to turn this shaft counterclockwise, as viewed in Fig. 2, and the parts are positioned, as shown in Fig. 3, with the pin 22 up against the shoulder of the opening 2|. The parts may be returned to the connecting position by reversing the operation just described.

The bridging contacts 8 are preferably provided with cylindrical contacting surfaces so that a high pressure line contact may be obtained when the bridging contacts are in the connecting position and clamped tight. It will be observed that, since the bridging contact 8 is parallel to the bridging contacts 9, H1 and H and since the current is passing through these in the same direction when they are in the connecting position, the magnetic force due to the current tends more firmly to hold the bridging contacts in the conducting position. This is important since, in case of heavy current flow, as occurs under certain conditions of heavy load as well as faults, any movement of the bridging contacts relatively to the associated conductors would tend to cause damage by arcing and otherwise.

In Fig. 4, which illustrates a part of a low voltage alternating current network system, a high voltage feeder comprising conductors 25' is connected to the low voltage conductors 2% through transformer 2?, connecting devices 28 embodying my invention, the circuit breaker 29 of the network protector and the fuses 30. With this arrangement, it will be apparent that the protector, which comprises the circuit breaker 29, may be isolated from the network low voltage conductors 26 by removal of the fuses 30 and from the low voltage side of the transformer by operating the disconnecting devices 28 to the disconnected position shown in Fig. 3. For this purpose the disconnecting device 28 may be supported on the conductor on the transformer side, as shown, although this is immaterial so far as my invention is concerned.

While I have shown and described my invention in considerable detail, I do not desire to be limited to the exact arrangements shown, but seek to cover in the appended claims all those modifications that fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Means for establishing a current conducting connection between the ends of two spaced conductors comprising two bridging contacts and means for supporting and elfecting movement of said contacts to bridge the space be tween said conductors rotatably mounted on one of said conductors and extending across the space between the ends of the conductors, said rotatably mounted means including means for effecting translatory movement from rotary movement, and means for effecting translatory movement of said contacts toward said conductors adapted to hold the contacts in current conducting relation with the conductors.

2. Means for establishing a current conducting connection between the ends of two substantially collinear spaced conductors comprising a plurality of bridging contacts and means for supporting said bridging contacts on one of said conductors for translatory movement longitudinally thereof comprising a member rotatably supported on said bridging contacts substantially perpendicular to the line of said conductors and a cam eccentrically mounted on and movable with said rotatable member, and means for moving said contacts lengthwise of said rotatable member and holding them in position against said conductors.

3. Means for establishing a current conducting connection between the ends of two substantially collinear spaced conductors each presenting two substantially parallel faces comprising a plurality of bridging contacts and means for supporting said bridging contacts on one of said conductors for translatory movement longitudinally thereof comprising a member rotatably supported on said bridging contacts and a cylindrical cam eccentrically mounted on and movable with said rotatable member, and means for moving said bridging contacts transversely to and holding them in position against the parallel faces of said conductors.

4. Means for establishing a current conducting connection between the ends of two approximately aligned tubular spaced conductors comprising a plurality of bridging contacts and means for supporting one of said contacts on one side of said conductors and another of said contacts on the opposite side of the conductors for translatory movement lengthwise of the conductors comprising means extending transverse- 1y of said conductors and rotatably supported thereon and on one of said contacts in the opening between the ends of the conductors, said rotatable means including means for changing rotary movement into translatory movement, and means for moving said contacts transversely to said conductors adapted to hold the contacts in current conducting relation with the conductors.

5. Means for establishing a current conducting connection between the ends of two spaced conductors comprising two bridging contacts and means for supporting and effecting movement of said contacts to bridge the space between said conductors rotatably mounted on one of said conductors and extending across the space between the ends of the conductors, said rotatably mounted means including means for effecting translatory movemerit from rotary movement, means for effecting translatory movement of said contacts to- Ward said conductors adapted to hold the contacts in current conducting relation with the conductors, and means for maintaining said contacts in substantial alignment with the ends of said conductors during the movements of the contacts.

6. Means for establishing a current conducting connection between the ends of two approximately collinear rectangularly shaped tubular spaced conductors comprising a plurality of biidging contacts and means for supporting one of said contacts on one side of said conductors and another of said contacts on the opposite side of said conductors for translatory movement lengthwise of the conductors comprising a shaft journaled in said contacts and extending transversely of said conductors in the opening between the ends thereof, a cylindrical cam eccentrically mounted on said shaft and rotatable therewith, bearing means for said cam mounted on one of said conductors, means for limiting the angular movement of said cam, and screw means for moving said contacts lengthwise of said shaft to engage said conductors adapted to hold the contacts in current conducting relation with two outer opposite sides of said conductors.

7. Means for establishing a current conducting connection between the ends of two approximately collinear rectangularly shaped tubular spaced conductors comprising a plurality of bridging contacts and means for supporting one of said contacts on one side of said conductors and another of said bridging contacts on the other side of said conductors for translatory movement lengthwise of the conductors comprising a shaft journaled in said contacts and extending transversely of said conductors in the opening between the ends thereof, a cylindrical cam eccentrically mounted on said shaft and rotatable therewith, bearing means for said cam mounted on the end of one of said conductors, means for limiting the angular movement of said cam, means cooperating with said bearing means to prevent movement of said contacts transversely to said shaft, and screw means for moving said contacts lengthwise of said shaft to engage said conductors adapted to hold the contacts in current conducting relation with two outer opposite sides of said conductors.

8. Means for establishing a current conducting connection between the adjacent ends of two conductors comprising bridging contacts, and supporting means for said contacts mounted on one of said conductors and interposed between said ends of said conductors, said supporting means including means for effecting longitudinal and transverse movement of said contacts relatively to said conductors.

BENJAMIN E. SPIRO.

Images