US2221607A - Reinforcement for contact members - Google Patents

Description

I INVENTOR. MW WM Mm W Sczmzelz'u's.

REINFORCEMENT FO R CONTACT MEMBERS Filed July 16, 1938 WITNESSES:

REINFORCED [EN]? FOR CONTACT MEMBERS John W. Samzclius, Pittsburgh, Pa., assignor to Westinghouse Electric & Manufacturing Com- Patented Nov. 12, 1940 pany, East Pittsburgh, Pa., a corporation of Pennsylvania Application July 16, 1938, Serial No. 219,516

6 Claims.

My invention relates, generally, to electrical contact members and, more particularly, to contact members or switch jaws designed for ,use with knife blade switches and fuses of the knife (Cl. 200-166) I partially in sectionxof a modification of the invention;'

Fig. 6 is a view, inside elevation, of one of the reinforcing members utilized in the modified blade type. stnfizture shown in Fig.5; V 5

For certain applications, it isdesirableto-sup- Fig. '7 is a view in side elevation of one ofthe plement the inherent pressure. of the jaws with looking plates for the modified structure; auxiliary pressure producing or reinforcing Fig. 8 is a view in 'plan' of a pair of the locking means in order to increase the contact pressure plates, and

between thecurrent conducting parts, Further- Fig. 9 is a view, in plan, of a pair of the locking 10 more, by providing auxiliary reinforcing means, plates with a tool for inserting the plates through thejaws may be made from copper without the the openings in the reinforcing members and the danger of the jaw becoming distorted to the exswitch jaw. tent of losing its resiliency. The use of copper Referring now to the drawing, andparticujaws is desirable because of its high conductivity larly to Fig. l, the structure shown therein comand relative cheapness as compared with other prises a jaw In, which is of substantially a materials. Heretofore, considerabledifficulty U-shape, having an enlarged base portion H, has been experienced in satisfactorily securing suitable for securing to a base plate (not shown), the auxiliary reinforcing means in position on and a pair of spaced fingers l2 for engaging the the contact members. i blade of a knife switch or a fuse of the knife- 20 An object of the present, invention, generally blade type (not shown). As explained hereinstated, is to provide a reinforced contact membefore, the jaw I0 is preferably made from copber which shall be simple and efiicient in operaper, although other suitable materials may be tion and which may be readily and economically utilized if desired. v

manufactured and installed. In order to'increase the contact pressure be- 25 A more specific object of the invention is to tween the fingers l2 and the. switch blade, a provide a reinforcing. memberfor a flexible jaw reinforcing member or spring [3 is provided for which may be removed readily from the jaw. each one of .the fingers l2. The reinforcing Another object of the invention is to provide a members l3 are preferably made from spring means for retaining resilient reinforcing-memsteel, or other suitable material, having a high 30 bers in position on contact 'jaws which will perresiliency. As shown in Fig. 1, they are so mit easy adjustment of the spring tension on shaped at the bottom that they conform with the the jaws. I shoulders it of the jaw l0.- Each reinforcing Other objects of the invention will be explained member I3 is provided with an inverted T-shaped fully hereinafter or will be apparent to those .opening is as shown in Fig. 2. ,If desired, the 35 skilled in the art. opening I5 may be made with the top of the T In accordance with one embodiment of the disposed uppermostinstead of inverted, present invention, the spring reinforcing mem- 1 The T-shaped opening I5 are provided for the bers for a switch or fuse jaw are retained in purpose of admitting a ocking piece It, having e 40 position bya locking piece of such a shape that enlarged ends or heads ll as shown inFig. 3, 4 it may be readily inserted in the reinforcing and a filler piece 18 that prevents the locking members and the jaw members through openings piece Hi from dropping down into the wide porin these members and then releasably held in the tion of the T-shaped hole in the spring I3 when looking position in which it engages the reinassembled, as shown in Fig. 1. The locking piece.

forcing members. I6 is preferably made from cold-{rolled sheet 45 For a fuller understanding of the nature and steel, spring steel or other suitable, material by objects of the invention, reference may be had to a punching operation. The filler piece I8 is likethe following detailed description, taken in conwise a punching fromany soft and durable steel junction with' the accompanying drawing, in that permits the ends to be bent over and thus which: i held in place, as shown in Fig. 1'. The one end Figure 1 is a view, partially in end elevationof the filler piece is preferably bent at l9, as and partially in section, of a reinforced jaw shown in Fig. 4, before the piece is inserted in constructed in accordance with my invention; the openings 15. I

' Fig. 2 is a view, in side elevation, of one of the It is apparent that the wide portion of the reinforcing members; T-shaped opening [5 must be large enough to Fig. 3 is a view, in plan, of a locking member; admit the head I! of the locking piece Hi. It

Fig. 4 is a view, in plan, of a filler member is also apparent that the narrow portion of the which is utilized to retain the locking member hole l5 must be slightly larger than the body in the locked position; of the locking piece l6 but smaller than the head e0 Fig. 5 is a. view, partially in end elevation and IT in order that the shoulders of the locking piece will engage the spring I3 when the locking piece is raised into the narrow portion of the opening I5.

In order to simplify the tools'required to perform the punching operations, the holes through the copper fingers I2 should be made rectangular in shape and a size corresponding to the maximum dimensions of the T-shaped holes in the springs I3. The location of the holes should be such that the locking piece I6 serves as a stop for the fuse or switch blade when inserted between the fingers I2.

When assembling the springs, the only tool required is a simple fixture or a pair of pliers to compress the springs I3 while the locking piece I6 and the filler piece I8 are being inserted through the springs I3 and the fingers I2 of the jaw III. After the members are assembled in their proper positions, the one end of the filler piece may be bent over easily with a screw driver or a hammer to retain the filler piece in position.

If it is desired to remove the springs in order to refinish the contact surfaces of the fingers after they have been in service, this may be done easily by utilizing a pair of pliers to straighten out the filler piece and then compress the springs I3 while the filler piece and the locking piece are being removed. Also, adjustment of the spring tension can .be made easily at any time in the field by inserting U-shaped washers .of a desired thickness between the heads of the locking piece I6 and the springs I 3.

In the modification of the invention shown in Figs. to 9, inclusive, in which similar parts are designated by the same reference character as in Figs. 1 to 4, inclusive, two locking pieces are utilized instead of one locking piece and one filler piece. The locking pieces are made from curved spring steel, as shown in Fig. 8. They may be inserted edgewise through the spring members in order that the high edges will serve as a stop for the fuse or switch blade.

As shown in Fig. 6, the opening I5 is widest at the center and narrow at each side, thereby providing shoulders for the heads of both locking pieces I6. The assembly in this case is easily maderby inserting one end of each locking piece in a small block 2|, as shown in Fig. 9. The

free ends are then pinched together with a. pair of pliers and the block inserted through the spring and jaw assembly, the springs being com:

pressed in an assembly fixture or by means of an-- other pair of pliers. Releasing the pliers which hold one end of the locking pieces and removing the block from the other end will permit the curved locking pieces to engage the springs and keep them under the proper tension as determined by the length of the locking pieces. The two locking pieces are identical and can be punched and formed cold from spring steel without annealing or heat treatment.

From the foregoing description, it is apparent that -I have provided a contact structure which may be manufactured cheaply and may be readily assembled. Furthermore, the locking members'which I have provided are of a durable construction and will, therefore, stand the severe vibration and rough usage,to which switch and fuse structures are frequently subjected. The structure may be easily disassembled and reassembled in the field if desired, thereby facili-' tating'the'repairing or renewing of worn parts. 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. The combination with a jaw having a base and spaced resilient fingers for engaging a movable member therebetween, of a spring for reinforcing each of said fingers, r removable locking piece for retaining the springs in position on the fingers, and'a removable member coextensive with said locking piece for releasably retaining the locking piece in position.

2. The combination with a jaw having a base and a pair of spaced resilient fingers for engaging a movable member therebetween, of a pair of oppositely disposed springs for reinforcing said fingers, a removable locking piece for engaging both of said springs for releasably retaining the springs in position on the fingers, and a removable member coextensive with said locking piece for releasably retaining the locking piece in position.

3. The combination with a jaw having a base and a pair of spaced resilient fingers for engaging a movable member therebetween, of a pair of oppositely disposed springs for reinforcing said fingers, each of said springs having an opening therein with a restricted portion, a removable locking piece disposed in the restricted portion of said opening and having enlarged heads disposed to engage both of said springs for releasably retaining the springs in position on the fingers, and means for retaining the locking piece in the restricted portion of said opening.

4. The combination with a jaw having a base and a pair of spaced resilient fingers for engaging a movable member therebetween, of a pair of oppositely disposed springs for reinforcing said fingers, each of said springs having an opening therein with a restricted portion, a removable locking piece disposed in the restricted portion of said opening to engage both of said springs for releasably retaining the springs in position on the fingers, and a removable member for releasably retaining the locking piece in the restricted portion of said opening.

5. The combination with a jaw having a base and a pair of spaced resilient fingers for engaging a movable member therebetween, of a pair of oppositely disposed springs for reinforcing said fingers, each of said springs having a T-shaped opening therein, a removable locking piece disposed in the narrow portion of said opening to engage both of said springs for releasably retaining the springsin position on the fingers,

and a removable filler piece disposed in the'wide portion of said opening to retain the locking piece in said narrow portion.

6. The combination with a jaw having a base

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