US2674772A - Clamp - Google Patents

Description

H. L. JACOBS April 13, 1954 CLAMP Filed Sept. 19, 1951 INVENTOR HENRY L. JACOBS Patented Apr. 13, 1954 UNITED STATE-S PATENT OEFFlC'E CLAMP Henry Lyman Jacobs, Wilmington, Del-., assignor to Baldwin-Lima -'Hamilton Corporation, a corpo'ration ofPennsylvania Application September 19, 1951,"SerialNo. 247,27.6

(Cl.i24125) '2 Claims. I

'This invention relates generally to clamping devices for cables, particularly electric cables with heavyin'sulated covering, and it is an obiect'of my'inven'tion'to provide "aclamp that will possess a high degree'of lateral and'vertical self- .adjustment to clamp and support "a group of individual parallel cables.

Another object is to provide an improved "clamp that will "exert clamping pressure on a group of cables from four directions by the application of an operating force from but one direction.

A further object is to provide a screw type clamp that eliminates bending or splitting of the cable clamping bars.

Other objects and "advantages will be more apparent totho'seskille'd'inthe art from the following description 'of'theaccompanying' drawings in'which:

Fig. 1' is aperspectivepf mynovel clampwith "an'end portion'thereof'brokenaway to show an elongated hole through a wedge-shaped spacer member;

Fig. '21s a side elevation of the clamp showing two tiers of cables, each tier containing four cables, clamped together by the device, and an end thereofbeing broken -awayto show passage of a stud through the clamping members; and

Fig. 3 is a side elevation of a modification of my clamp.

In the particular embodiments of the invention I have shown, in Figs. 1 and 2, a metal plate I forming either a separate base or a part of locomotive frame, to which are welded or otherwise secured two perpendicular threaded studs 2 and 3. Two identical cable support bars 4 and 5, preferably made of a hard wood, are provided with perpendicular holes I to receive threaded studs 2 and 3. The support bars have thick ends provided with inclined outwardly converging, substantially flat cam surfaces 8 and 9, through which holes I extend, these surfaces preferably being approximately at an angle of 30 with clamping surfaces II) which are intermediate of the cam surfaces 8 and 9.

Positioned between the opposed pairs of inclined surfaces 8 and 9 are wedge-shaped lateral clamping members I2 having holes I3 laterally elongated. Each member I2 has a cable-engaging surface I4 and two converging surfaces I5 and I6 in sliding engagement with inclined surfaces 8 and 9.

With the four clamping elements mounted on the studs 2 and 3 as shown in Figs. 1 and 2, to form substantially a rectangular cable aperture I I, the lateral clamping elements I 2 are "freeto slide laterally inwardly as the top and bottom elements are-drawntogether 'by nuts I? on the studs. Cables 'I8,-or'the like, 'havingusually a resilient outer covering and running through cable aperture I I are thus vertically and laterally clamped between surfaces Ill and Id. "The relative lengthsof the inclined surfaces-omelementsd, 5 and I2 are'such'thatpressure can-be exerted both'laterally and-verticallyon th'e cables before the bars come into-'contactwith' the'latera'l wedges. 7

As converging surfaces I5 and I6 are always in engagement with inclined surfaces Sand- 9, there is no possibility that excessive pressure on'supportbar 4 will bend or split the bar, as frequently happens in using some of the conventional clamps. So long as wedge-shaped members I2 can move inwardly no excessive pressure can be exerted by the screw means and when members I2 reach theirlimit bycontact with the cables they function as a spacer toform a solid foundation against any excessive pressure that may thereafter be exerted by the screw means.

WhileFig.'2 shows two tiers of *cablesdispose'd between support bars 4 and 5' and between "wedges I2, it is to be understood that the length or cableengaging surface I ll 'of the support bars may be altered to provide for'more or less cables in each tier. Similarly, by merely altering the height of spacer member I2 and the lengths of studs 2 and 3, the number of tiers of cables may be increased or decreased as required.

In Fig. 3 I show a modification of my screw clamp to provide for cases where there is but one tier of cables. As in the preferred form, there are two parallel support bars I9 and 20, only one of which, however, is provided with inclined surfaces 2I corresponding to inclined surfaces 8 and 9 of the preferred form. Also, each wedge member 22 has but one inclined surface 23 in sliding engagement with an inclined surface 2| of bar I9. Another side 24 of member 22 slidingly engages cable-engaging surface 25 of bar 20, while the third side 26, at right angles to side 24, is also a conduit-engaging surface. An elongated hole 21 is similarly disposed through each wedge. Thus, when pressure is exerted on the clamping members by means of studs 28 and nuts 29, bars I9 and 26 move toward each other while spacer members 22 move inwardly along surface 25 of bar 20 and inclined surfaces 2| of bar I9.

In installations where the clamp is to be used against a metal surface, base plate I may be dispensed with and the studs welded perpendicularly direct to the metal surface. The screw clamp described herein has the further advantage of better sealing the aperture of a wall through which the cables may pass against dirt, sand and other wind-borne particles in that sides 30 of the parallel support bars and sides 3| of the spacer members are fiat and in the same plane, enabling the clamp to be placed directly against the wall or floor over the aperture through which the cables pass.

It is seen from the above description that I have provided a screw clamp that is self-adjusting to fit diameter variations in cables, and other conduits, that exerts clamping pressure from four directions against the cables by the application of pressure from but one direction, that prevents the bending or splitting of the cable support bars through the application of excessive pressure, and that seals the aperture in a flat surface through which the cables pass. The self-adjustment arises from the feature that the cable aperture always remains fundamentally of rectangular shape regardless of whether it is opened or closed to various extents to accommodate cables of one diameter for one installation or of another diameter for another installation.

It will, of course, be understood that various changes in details of construction and arrangement of parts may be made by those skilled in the art without departing from the spirit of the invention as set forth in the appended claims.

I claim:

1. A clamp for a plurality of cables or conduits 'of substantially the same diameter, comprising,

the support bars thereby forming a rectangular opening with the parallel cable engaging surfaces of the support bars being disposed intermediate of the lateral clamping elements and of the cam surfaces 8 and 9, said lateral clamping elements and said support bars having outwardly converging complementary slidably engageable substantially flat surfaces whereby the support bars when moved toward each other effect a clamping force on each individual cable or conduit in a direction normal to the support bars and also effect movement of the lateral clamping elements toward each other to exert a lateral clamping force on the layer of cables or conduits in a di rection aligned with the plane of their axes, thereby subjecting all of the cables or conduits individually to substantially the same clamping pressure in the plane of said layer and to substantially the same clamping pressure in the direction normal to said plane, and bolts extending substantially normal to the flat surfaces of the support bars and through said bars outwardly of said intermediate surfaces so as to effect said clamping pressures upon tightening of said bolts.

2. The combination set forth in claim 1 further characterized in that the lateral clamping elements have inclined surfaces on opposite sides respectively engageable with complementary inclined surfaces on each of the support bars at each end thereof, said surfaces converging toward each other at a point beyond the ends of the support bars, and the support bars extending over both of the inclined surfaces of the clamping elements.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 558,165 Evans Apr. 14, 1896 591,796 De Wolf Oct. 12, 1897 1,522,013 Goodall Jan. 6, 1925 2,097,470 Richardson Nov. 2, 1937 2,348,096 Schack May 2, 1944 2,548,401 Sherwood Apr. 10, 1951 FOREIGN PATENTS Number 7 Country Date 233,963 Great Britain May 21, 1925 474,756 Germany Apr. 11, 1929 208,239 Switzerland Jan. 15, 1940

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