US2220698A - Terminal clamp - Google Patents

Description

F. B. ADAM ETAL TERMINAL- CLAMP Nov. 5, 1940.

Original Filed May 11, 1936 4 SheetsSheet l INVENTOR.

FREDERICK .B. ADAM l/E'NR) M. -57"/E'&l-IT'Z BY 0307 4% ATTORNEY.

Nov. 5, 1940. F. B. ADAM ETAL TERMINAL CLAMP Original Filed May 11, 1936 4'Shets-Sheet 2 mwm m c W? 1B&% My Rr f W SW 2 w w ATTORNEY.

Nov. 5,. 1940.

F. B. ADAM ET AL TERM INAL CLAMP Original Filed May 11, 1936 4 Sheets-Sheet 3 Nov. 5, 1940. F.'B. ADAM ET AL 2,220,698

TERMINAL CLAMP Original Filed May 11, 1936 V 4 Sheets-Sheet 4 INVENTOR. FPEDER/CK B. flax-v1 HENRr M. 87-15-62 17-2 A TTORNE Y.

Patented Nov. 5, 1940 UNITED STATES TERMINAL CLAMP Frederick B. Adam, St. Louis County, and Henry M. Stieglitz, St. Louis, Mo., assignors to Frank Adam Electric Company, St. Louis, Mo., a corporation of Missouri Application May 11, 1936, Serial No. 79,050 Renewed April 4, 1940 15 Claims.

This invention relates to clamps for knife blade and ferrule type fuses and other terminal connections.

Most connections with the knife blade terminals of a fuse or other device are made with clips. These clips depend upon the spring of the material from which they are made to cause tight contact between the knife blade terminal and the clip. It is practically impossible to make .a simple clip which will maintain tight contact with the knife blade terminal and yet allow easy removal or insertion of the knife blade terminal. If the clip is designed to allow the knife blade terminal to be easily inserted into or removed :from the clips, the contact between the clip and knife blade will not be tight enough to prevent undesirable heating at the terminals, while if the clip is designed to tightly clamp the knife blade terminal, it will be diflicult to insert or remove the knife blade terminal.

It is an object of this invention to provide a clamp which may be applied to the standard fuse clips now in use to allow easy insertion.

and removal of the fuse and yet insure good contact between a knife blade terminal of a standard fuse and the fuse clip.

Another object of this invention is-to provide a clamp which may be applied to standard capacity fuse clips even-after installation of the fuse block or switch.

Another object of this invention is to provide a current carrying knife blade terminal support which will replace the commonly employed clip and which is equipped with a clamp to cause the knife blade terminal support to make good contact with a knife blade terminal which may be clamped thereto.

Another object of this invention is to provide a knife blade terminal support which may be formed on a part of another current carrying part and when equipped with a suitable clamp will form a knife blade terminal support which allows a knife blade terminal to be inserted therein or thereon easily and yet after operation of the clamp insures good contact between the knife blade terminal and the support.

Another object of this invention is to provide a clamp which may be used inside of a cartridge fuse of the renewable type to secure the fuse link to the fuse terminal, and to provide the clamp with a means to prevent the assembly of the fuse link in the casing until the clamp is closed.

Further objects and advantages of this invention will appear from the following detailed description of various forms thereof. We do not desire our invention to be limited thereby, but to be defined by the appended claims.

In the drawings,

Fig. 1 is a perspective view of a fuse holder embodying our invention, 7

Fig. 2 is a perspective view of one of the knife blade terminal supports shown in Fig. 1,

Fig. 3 is a perspective view of one of the cam striker plates shown in Fig. 1,

Fig. 4 is a perspective view of one of the U shaped slotted members assembled in Fig. 1,

Fig. 5 is a perspective view of one of the cams with handle attached shown assembled in Fig. 1,

Fig. 5a is a perspective view of a modified form t; of cam.

Fig. 5b is a perspective view of a modified form of cam and key,

Fig. 6 is a perspective view of a positioning strap shown assembled in Fig. 1, 20

Fig. 7 is a vertical sectional view of the device as viewed along line 1-1 of Fig. 1,

Fig. 8 is an enlarged sectional view taken along line 8-8 of Fig. 7, with the handle in holding position,

Fig. 9 is a view similar to Fig. 8, but the handle is in open position,

Fig. 10 is a sectional Ill-I0 of Fig. 9,

Fig. 11 is a side view of a conventional clip type fuse-holder equipped with one form of clamp a embodying our invention,

Fig. 12 is an enlarged side view partly in sectionof one of the clamps as applied to a con-, a ventional fuse clip,

Fig. 13 is a plan view of the clamp shown in Fig. 12,

Fig. 14 is a sectional view taken along line H-H of Fig. 12 with the clamp handle in holding position, 40

Fig. 15 is a view similar to Fig. 14 except that the clamp handle is in open position,

Fig. 16 is a view along line IS-J6 of Fig. 15,

Fig. 17 is a perspective view of the cam lever of the clamp shown in Fig. 11,

Fig. 18 is a perspective view of the U member of the clamp shown in Fig. 11,

Fig. 19 is a perspective view of the sub-plate of the clamp shown in Fig. 11, 50

Fig. 20 is a perspective view of a form of our inventiondesigned to hold a ferrule type fuse,

Fig. 21 is a perspective view of an assembled cartridge fuse utilizing one form of our clamp view taken along line to secure the fuse link to the fuse terminal, 55

Fig. 22 is a cross sectional view taken along line 2222 of Fig. 21,

Fig. 23 is a cross sectional view taken along line 23-23 of Fig. 21,

Fig. 24 is a perspective view of a modified form of our clamp as applied to a fuse terminal connection, and

Fig, 25 is a cross sectional view taken along line 2525 of Fig. 24.

Several types of clamps are shown in the drawings. One type employing a slotted bar member as a knife blade terminal receiving contact is shown in Figs. 1 to 10. Referring now to the drawings, the numeral 20 indicates a base to which a bar member 22 provided with a slot 23 may be secured by a bolt 24 passing through a hole 26 in the base and screwed into a threaded hole 28 of the slotted bar member. The base as shown may be of any insulating material such as fibre or slate and may be an individual block or a part of a panel or other electrical apparatus. The slotted bar member may be provided with a wire terminal connection or lug or may be a part of some other electrical conductor or apparatus. A lug 30 is shown secured to the bar member by a nut 32. A clamp may be assembled on the bar member from a main clamping member 34 which is provided with slots 36 in the opposite sides thereof as shown. These slots allow the main clamp member to be placed over the slotted bar member as shown in Fig. 1, causing one side of the main clamp member to be positioned adjacent to an edge of the bar member. The numeral 38 denotes a striker plate which is formed substantially as shown and fits over an edge of the bar member as shown in the drawings. A cam member 40 may have a handle 4! formed integral therewith to provide a cam lever. The cross section of this cam member is shown in Figs. 8 and 9 40' where it can be seen that the cam member may be made from a rod with one side thereof flattened off or by other suitable means. The cam member may be positioned between the striker plate and the side of the main clamp member ad- 45 jacent the bar member. The slots in the main clamp member are so formed that the cam member may be supported therein and have one side in contact with the included or adjacent side of the main clamp member while the other side is 50 in contact with the striker plate. The striker plate may be omitted, if desired, and contact made against one edge of the bar member instead. Figs. 8 and 9 show that with the cam member in position as shown in Fig. 8, the slot 55 in the bar member is made narrower than when the cam member is in the position shown in Fig. 9. When the knife blade terminal 42 of a fuse 43 or other apparatus is inserted in the slot of the bar member, a very great clamping action is exerted thereon when the cam is in the position shown in Fig. 8.

A stop 44, which may be supported by one of the main clamp members, may be provided to properly position the knife blade terminals in the slots of the bar members.

The main clamp member 34 may be positioned on the bar member 22 by a spring 45 which can be inserted in anarrow slot 46 in the bar member.

Two of the slotted bar members with the assembled clamps may be positioned on a base to hold a standard knife blade type fuse 43 as shown in Fig. 1. The successive steps of inserting a fuse in the bar member are illustrated in Fig. 7. The 75 cam members are first placed in the position shown in Fig. 9. The upper blade terminal of the fuse is then inserted as far as it will go into the upper slotted bar member as shown in position A. The fuse is then swung through position B and then into position C where the lower knife blade terminal of the fuse is allowed to drop through the slot in the lower slotted bar member and be positioned by the stop 44. The cam members are then rotated to the position shown in Fig. 8 and the fuse is clamped tightly in place. The clamping action of the bar member on the knife blade terminal is very great and thus prevents any heating of the fuse terminals. The clamp and slotted bar are very simple and thus easily and cheaply made and assembled. 'The slotted bar member is superior to the usually employed clip because it may form a part of a conductor or other apparatus part as a single piece member. The use of a clamping means enables a bar member or conductor bar to have a fuse terminal clamped thereto with the axis of the fuse extending perpendicular to the plane of the conductor or bar member as shown. This makes it possible to use the same bar member to which the fuse is clamped as a conductor bar either formed on or directly connected with other apparatus parts. Such use is impossible with clips, for a separate member must be used for the clips in each connection.

A type of clamp which may be applied to the commonly employed type of clip is shown in Figs. 11 to 19, where the numeral 50 indicates a clip of the conventional type secured by a bolt 52 and nut 54 to a base 55. A conductor bar 56 is clamped under the clip and has a lug 51 secured thereto by a bolt 58 and nut 59. The above method of assembling the clips and conductors is merely given as one example of a suitable clip assembly to which our clamp may be applied. The clamp about to be described may be applied to old clip installations and does not necessitate the removal of the clips from the base or panel to which they are secured. The clamp may be assembled on the clip from a main clamp member or U member 62 provided with recesses 64 in opposite edges of one side thereof, a sub-plate 66 provided with flanges 68 on two opposite sides with recesses or openings 10 and H therein and lugs 12 on two other opposite sides, and a cam member 14 which may have a handle 16 formed integral therewith. The cam member may be formed from a rod with one side thereof flattened as shown and a portion ll of reduced area may be provided to fit into the recess 10 which may be smaller than the recess ll of the sub-plate. When assembled on a fuse clip the cam member is supported in the recesses of the sub-plate and separates the sub-plate from one side of the main clamp member while the flanges of the sub-plate interfit with the recesses 64 of the main clamp member. When assembled around a clip as shown in the drawings, the lugs 12 serve to position the sub-plate and thus the clamp on the clip. When the cam member is rotated to the position shown in Fig. 14 of the drawings, the sides of the clip are brought closer together than when it is in the position shown in Fig. 15 of the drawings and thus produce a clamping action on a knife blade terminal 18 when inserted in the clips. If the clips are spaced as in Fig. 11 to hold a knife blade type fuse 19, the fuse may be inserted in the clips in the usual manner with the clamps in open position as in Fig. 15 and then upon rotation the cams to the position shown in Fig. 14 by a handle or other means, the fuse terminals are tightly clamped in the clips, thus avoiding heating of the fuse terminals and yet allowing easy removal of the fuse terminals from the clips when the clamps are opened.

In Fig. 20 is shown a form of fuse terminal connection similar to the one shown in Figs. 1' to 10, but adapted to accommodate a ferrule type fuse. The slotted bar member 22 is provided with a circular opening 80 of suitable dimensions to accommodate the desired size of ferrule type fuse terminal. The clamp and slotted bar member cooperate to clamp a ferrule type fuse in the same manner as the clamp and slotted bar member shown in Figs. 1 to 10 act upon a knife blade 4 terminal. E

Referring now to Figs. 21 to 23, the numeral 82 designates the knife blade terminal of a renewable type fuse cartridge provided with a circular member 84 designed to support a casing 86. A fuse link 88-is tightly clamped to the inner ends 90 of the knife blade terminals by a clamp 92 comprising a main clamp member 94 of steel or suitable material provided with ears 95 and openings 96 therein, a striker plate 91 provided with openings 98 and a cam member 99 provided with a flattened side I00 and supported in openings 96 in the main clamp member 94. A handle portion I02 of the cam member is so positioned as to be perpendicular to the plane of the fuse terminal when open and parallel thereto when in the clamped position as shown in Figs. 22 and 23. It is thus impossible to place the assembled link and terminals in the fuse casing until the clamps are tightened. This insures that the fuse cartridge cannot be placed in an electrical circuit until the fuse link makes proper contact with the fuse terminals. Improper operation of the fuse, because of heating caused by loose connection of the fuse link to the fuse terminals, is thus prevented.

A modified form of terminal clamp is shown in Figs. 24 and 25 where the numeral I04 indicates a base with a bar member I06 secured thereto by a bolt I08. A knife blade terminal H0 of a fuse III or other apparatus may be clamped to the bar member by a clamp assembled from a main clamp member H2 shaped substantially as shown and provided with openings H4, a striker plate H5 shaped as shown and provided with openings H6 and a cam member H8 having a flattened side H9 and a handle I20. The main clamp member may be secured to the bar member by a screw I22 threaded into a hole I24 in the 'bar member I06. The clamp is shown in closed position. It may be opened by rotating the cam by means of the handle until the flattened side of the cam member lies against the striker plate which allows the clamp to open for removal or insertion of the knife blade terminal.

The cam member in any of the clamps described may be rotated by other means than an attached handle as for instance a key 4Ia (Fig. 51)) designed to fit over a properly formed portion on the end of the cam member as shown in Fig. 5b. Fig, 5a shows a cam which may be rotated by a screw driver.

The small space required for the above described clamps makes it possibleto use them in conventional installations where no extra space is provided for screw drivers or other tools which might be needed with other types of clamps.

While we have illustrated and described several of the possible forms of our invention, we do not W desire it to be limited thereby, but to be defined by the following claims.

when inserted in the slot therein.

'2. A terminal connection comprising a bar member provided with a slot adapted to allow the insertion of a knife blade terminal therein,

a U member having two opposite and one in- 15 eluded sides provided with openings in the opposite sides thereof through which the bar member passes, a striker platepositioned against one Y edge of the bar member and a cam member positioned between the included side of the U mem- 20 ber and the striker plate and adapted to cause the bar member to exert a clamping action on a knife blade terminal when inserted in the slot therein, and a stop member supported on the U member and adapted to properly position a 25 knife blade terminal when inserted in the slot in the bar member.

8. A terminal connection comprising .a bar member provided with a slot therein adapted to allow the insertion of a knife blade terminal 30 therein, a clamp member embracing the bar member and a cam member positioned between a side of the clamp member and the bar member and adapted to cause the bar member to' exert a clamping action on a knife blade ter- 5" minal when inserted in the slot in the bar member.

4. Ai terminal connection comprising a bar member provided with a slot therein adapted to allow the insertion of a knife blade terminal 40 therein, a U member having two opposite and one included sides provided with openings in the opposite sides thereof through which the bar member passes and a cam member positioned between the included side of the U member and 45 the bar member and adapted to cause the bar member to exert a clamping action on a knife blade terminal when inserted in the slot in the bar member, and a stop member supported on the U member and adapted to properly position -50 a blade terminal when inserted in the slot in the bar member.

5. A terminal connection comprising a bar member provided with a slot therein adapted to allow the insertion of a knife blade terminal 55 therein, a main clamp member embracing the bar member and having one side thereof substantially parallel to one edge of the bar member, a striker plate positioned against one edge of the bar member and a cam member positioned 60 between the striker plate and the side of the main clamp member substantially parallel to an edge of the bar member and adapted to cause the bar member to exert a clamping action on a blade terminal inserted in the slot in the barmember when said cam member is suitably positioned.

6. A terminal connection comprising a bar member provided with a slot therein adapted to allow the insertion of a knife blade terminal therein, a main clamp member having opposite sides provided with openings through which the bar member passes and another side substantially parallel to one edge of the bar member, a striker plate positioned against one edge of the bar mem- 7 -ber and a cam member positioned between the striker plate and the side of the main clamp member substantially parallel to an edge of the bar member and adapted to cause the bar member to exert a clamping action on a knife blade termi'hal when inserted in the slot in the bar member when said cam member is rotated to the proper position.

7. A terminal connection comprising a bar member provided with an opening therein adapted to allow the insertion of a terminal therein, a clamp member provided with an opening therein through which the bar member passes and a cam member positioned between the clamp member and the bar member and adapted to cause the bar member to exert a clamping action on a terminal inserted in the opening in the bar member when said cam member is suitably positioned.

8. A terminal connection comprising a bar member provided with an opening therein adapted to allow the insertion of a terminal therein, a clamp member provided with an opening through which the bar member passes and a cam member positioned between the clamp member and the bar member and adapted to cause the bar member to exert a clamping action on a terminal inserted in the opening in the bar member when said cam member is suitably positioned, and a stop member supported by said clamp member and adapted to position a terminal when inserted in the slot in the bar member.

9. A fuse terminal connection comprising a bar member provided with. an opening therein adapted to allow the insertion of a ferrule type fuse terminal therein, a main clamp member embracing said bar member and a cam member positioned between the bar member and the main clamp member and adapted to cause the bar member to exert a clamping action on a ferrule fuse terminal when inserted in the opening in the bar member.

10. A fuse terminal connection comprising a supporting base, a flat bar member extending at right angles therefrom, provided with an opening therethrough at right angles to the face of the bar member adapted to allow the insertion of a fuse terminal therein, a slot through the bar member extending from the opening to an outer edge of the bar member, a clamp member positioned on the bar member and a clamp actuating member positioned to actuate the clamp member and move portions of the bar member on opposite sides of the slot together to clamp a fuse terminal in the opening.

11. A fuse terminal connection comprising a bar member adapted to make contact with a ferrule fuse terminal with the axis of the fuse perpendicular to the face of the bar member a main clamp member positioned on said bar member and a cam member effective to cause a ferrule fuse terminal to be clamped against the bar member when said cam member is suitably positioned.

12. A fuse terminal connection comprising a supporting base, a fiat bar member extending at right angles therefrom, a slot through the bar member at right angles to the face of the bar member adapted to allow the insertion of a fuse terminal therein, a clamp member positioned on the bar member and means to actuate the clamp member to move the portions of the bar member on opposite sides of the slot together to clamp a fuse terminal therebetween. V

13. A fuse terminal connection comprising a supporting base, a flat bar member extending at right angles from the supporting base, an opening through the bar member at right angles to its face, a slot extending from the opening to the outer edge of the bar member, and clamp means to move the portions of the bar member on opposite sides of the slot together to clamp a fuse terminal in the opening.

14. A fuse terminal connection comprising a supporting base, a flat bar member extending at right angles from the supporting base, a slot therethrough at right angles to the face of the bar member, said slot being adapted to receive the terminal of a fuse, and means to move the portions of the bar member on opposite sides of the slot together to clamp a fuse terminal therebetween.

15. A fuse terminal connection comprising a supporting base, two spaced apart flat bar members extending at right angles from the base and positioned with their faces parallel and opposed to each other, a slot through each bar member at right angles to the face thereof, each slot being adapted to receive the terminal of a fuse, and means to move the portions of the bar member on each side of the slot together to clamp a fuse terminal therebetween.

FREDERICK B. ADAM. HENRY M. STIEGLITZ.

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