US3253308A

US3253308A - Compression anchoring device

Info

Publication number: US3253308A
Application number: US386886A
Authority: US
Inventors: John F Jost
Original assignee: Fargo Mfg Co Inc
Current assignee: Fargo Mfg Co Inc
Priority date: 1964-08-03
Filing date: 1964-08-03
Publication date: 1966-05-31
Anticipated expiration: 1983-05-31

Description

y 1966 J. F. JOST COMPRESSION ANCHORING DEVICE 2 Sheets-Sheet 1 Filed Aug. 5, 1964 INVENTOR Joya! F. :rosr

BY K ATTORNEYS May 31, 1966 Filed Aug. 5, 1964 J. F. JOST 3,253,308

COMPRESSION ANCHORING DEVICE 2 Sheets-Sheet 2 XNVENTOR ATTORNEYS United States Patent 3,253,308 QOMPRESSION ANCHORING DEVICE John F. lost, Newington, Conn., assignor to Fargo Mfg. Company, Inc, Poughkeepsie, N.Y., a corporation of New York Filed Aug; 3, 1964, Ser. No. 386,886 14 Claims. (Cl. 24-126) This invention relates generally to devices known as dead ends which are used for anchoring a cable to a firm supporting surface and more particularly to that group of dead ends known as compression dead ends.

It often becomes necessary to firmly anchor the end of a cable, such as a messenger cable, to a supporting structure in a firm and permanent manner. The anchoring device must he easy to handle and economical to manufacture.

The invention herein disclosed has as its principal object the [furnishing of a new compression dead end which is relatively inexpensive, having few parts and which is simple to use.

It is another object of the present invention to provide a compression dead end which can be supplied as a unit and which will not require the use of special tools or unusual manipulations in the field.

A further object of this invention is to provide such a structure which will hold 'a cable end securely and firmly with-out danger of slippage assuring permanent alignment of the cable and uniform gripping action.

A compression anchoring device embodying the in vention and the manner of using the same is described herein with references to the drawings, in which:

FIG. 1 is an exploded perspective view of a compression dead end constructed in accordance with the teachings of this invention;

FIG. 2 is a longitudinal cross-sectional view taken along the line 2-2 in the direction of the arrows as indicated in FIG. 1 showing the dead end with a cable end inserted therein;

FIG. 3 is a partially sectional view taken along the line 33 in the direction of the arrows in FIG. 2;

FIG. 4 is a partially sectional view taken along the line 44 in the direction of the arrows as indicated in FIG. 3;

FIG 5 is a longitudinal cross-sectional view of an alternate embodiment of the invention in which the jaw member is not unitary but formed of (several individual jaw segments;

FIG. 6 is a partially sectional view taken along the line 66 in the direction of the arrows as indicated in FIG. 5;

FIG. 7 is a longitudinal view of an alternate form of dead end constructed in accordance with the teachings of this invention;

FIG. 8 is a longitudinal view of another alternate form of the invention constructed in accordance with the teachings herein;

FIG. 9 is a top view of another form of dead end constructed in accordance with the teachings of this invention;

FIG. 10 is a side view of the dead end shown in FIG. 9; and

FIG. 11 is a partially sectional view taken along the line 1111 in the direction of the arrows in FIG. 10.

The unit shown in FIGS. l through 4 consists essenti'ally of gripping member 10, flexible bail 11 and segmented jaw member 12. The members of the assembly can be formed from high-strength alloys of the same metal as is cable 13, the end of which is to be received within jaw member 12.

Jaw 12 includes four-jaw segments 14 separated by slots 15 and having a common base portion 16. Each of the jaw segments presents in its inner surface serrations or gripping teeth 17.

The base portion may be formed with openings 18 defining the inner ends of slots 15. The surface of the side walls forming the base portion is otherwise uninterrupted. In this manner an extremely resilient mounting is furnished for the jaw segments 14 while maintaining the strength of the gripping assembly.

In the preferred form of the invention the jaw segments 14 are four in number with each extending throughout an arc of slightly less than in the normal open position of the jaws as seen best in FIGS. 2 and 3. The outer surface of each jaw segment is provided over its greater portion with an incline or taper 19 providing a gradually decreasing outside diameter terminating in radially outwardly directed boss 20 at the end of the jaw away from base 16.

Gripping member 10 is provided with bore 21 having a diameter slightly greater than the outside diameter of jaw 12 immediately adjacent boss 20 with the segments in their normal position. In this position gripping member 10 cannot be removed or separated from the jaw 12 because of boss 20 and the increasing diameter of jaw 12 terminating in an outside diameter at base 16 greater than the diameter of the bore in gripping member 10. In the normal position of the jaw segments, as shown in FIGS. 2 and 3, thespace defined between the series of serrations or teeth 17 presents a diameter adequate to receive the end of cable 13. It is noted, however, that since the outside diameter of the jaw segments increases as the base is approached, movement of gripping member 10 to the right in FIG. 2 relative to jaw 12 will result in a constricting or pressing together of jaw segments 14 with a corresponding decrease in the distance between serrations or. teeth 17, resulting in the teeth being forced against and encompassing and embracing the body of cable 13 therewithin.

Bore 21 in member 10 can be tapered if desired to provide greater bearing :area'on taper l9 and to avoid cutting in on taper 19 by the leading edge of bore 21. Also, member 10 could be a portion of a supporting structure.

In the constricted condition of the jaws a force applied longitudinally to cable 13 in the direction of the arrow indicated by the letter A in FIG. 2 would tend to move jaw 12 to the left relative to gripping member 10 increasing the constriction and increasing the inwardly directed radial forces developed in the jaws and hence increasing the gripping ability of teeth 17 to maintain the cable end in position between the jaw teeth.

In the embodiment disclosed herein a flexible bail 11 is provided having enlarged head portions 22 connected :at its ends through intermediate neck portions 23. Neck portions 23 have a greater outside diameter than the bail but less than the head portions. The gripping member is provided with a hole 24 receiving one end of the bail with its head 22 on side 10:: of the gripping unit. The gripping unit is also provided with a keyway 25 having a central hole 26 of substantially the same diameter as hole 24, being slightly greater than neck 23, and the slot 25 is sufliciently wide to permit insertion of the bail therein but not wide enough to allow passage of neck 23 therethrough. The one end of the hail wire therefore is removable from the gripping unit to facilitate quick permanent installations.

The dead end disclosed is installed by threading the detached end of the bail wire through the supporting surface, suchas a bracket or rack. The detached end is then attached to the gripping unit and the messenger cable 13 extended through the gripping unit for connection to a neutral or ground conductor. The normal force such 3 as that applied as indicated in FIG. 2 by the arrow A would tend to cause the dead end to more firmly grip cable 13 since an equal and oppositely directed force indicated by the arrow B in FIG. 1 applied to the flexible hail occurs.

In the embodiment disclosed in FIGS. 1-4 the fastening portion is a flexible \bail. However, a stiff bail or other similar means can be employed.

Segmented jaw member 12 while shown as a single machined piece could be made of several rigid segments, such as segment 14, loosely held together with a collar at common base 16.

In the embodiment shown in FIGS. and 6, a dead end 27 is provided having a jaw member formed of four separate and individual jaw segments 28 aligned at one end by circular aligning collar 29 adjacent boss 39 and having the jaw member base formed by aligning pins 31, each of which projects from an individual jaw segment into a receiving hole 32 in an adjacent segment. The aligning collar 29 is provided wtih inner fiange 29'C which projects within the bore of the jaw member preventing complete collapse of the segments inwardly, and outer flange 29" preventing movement of the jaw members completely radially outwardly, and a boss gripping flange 29" which encompasses boss 30. The end of the jaw member is held loosely within the aligning collar, and does not interfere with the operation of the jaw member. Aligning collar 29 can be formed of any suitable material such as metal or plastic. In the embodiment shown there are four segments having an outside surface with a tapered portion 33 and an untapered portion 34 with internal gripping teeth 35 in the zone of taper 33. A spring 36 is shown between gripping member 37 and collar 29. A cup 38 for receiving the end of a cable and aiding its movement over the teeth is provided.

This configuration can be varied and more or less segments used. The taper can be modified and the use of spring 36, cup 38 and teeth, 35 can be eliminated in certain applications.

A modification of the invention is shown in FIG. 7 wherein dead end 39 is of the same general configuration as the dead end shown in FIGS. 1-4, however, the outer surface of each jaw segment in FIG. 7 is provided with a variable taper consisting of shallow tapered portion 40 and untapered portion 41. The gripping member in FIG. 7 is indicated by the numeral 42.

The variable taper on the jaw rather than the straight taper shown in the previous figures allows a snug rather than a loose fit of the gripping member 42 when the conductor is being inserted and also allows a tighter more secure fit when the grippping member is in the shallow tapered portion 40.

Another embodiment of the invention is shown in FIG. 8 wherein dead end 43 is illustrated consisting of shallow taper portion 44 and untapered portion 45 and wherein the gripping member is indicated by the numeral 46. A stationary collar 47 at the end of the unit is shown adjacent boss 48. With this arrangement the compression on the longer jaw is distributed since the end of the jaw is held by the separate collar 47 which is maintained in position by suitable means such as swaging. The gradually increasing squeeze from the mouth end to the maximum position under the movable gripping member allows for this even distribution of compression.

In FIGS. 9-11 another form of the invention is shown in which there is illustrated a dead end 50 utilizing a split jaw composed of

segments

51 and 52. The jaw is fiat and can be molded from a plastic material or stamped from sheet stainless steel providing the necessary resiliency for developing suitable compression forces on oval cable 53 by movement of gripping member 54 on the tapers or inclined surfaces 51a and 51b of

jaw segments

51 and 52, respectively. Bail 55 is shown in these figures to complete the illustration.

Thus, among others, the several objects in the invention as specifically aforenoted are achieved. Obviously, numerous changes in construction might be resorted to without departing from the spirit of the invention as defined by the claims.

I claim:

1. A compression anchoring device for holding the end of a cable including in combination a jaw member, a plurality of jaw segments of said jaw member, a jaw base joining said segments at one end with each of said segments normally spaced from adjacent segments, a jaw bore provided by said segments, an outer surface of each of said segments, an outwardly directed boss formed on each said outer surface on the remaining end thereof, a tapered portion of each of said outer surfaces providing a decreasing outside dimension of said jaw member in the direction of said boss, a gripping member, a bore of said gripping member receiving said jaw segments between said boss and said jaw base, and said bore of said gripping member being formed with a bore dimension greater than the outside dimension of said jaw member adjacent said boss and less than the outside dimension of said jaw member adjacent said jaw base whereby the dimension of said jaw bore is determined by the relative longitudinal position of said gripping member.

2. A compression anchoring device for holding the end of a cable in accordance with claim 1 in which an untapered portion of each of said outer surfaces is provided between said tapered portion and said boss forming a variable tapered outer jaw segment surface.

3. A compression anchoring device for holding the end of a cable in accordance with claim 1 in which a collar is provided through which said jaw segments project, said collar determining the maximum outside dimension of said jaw member whereat the collar is positioned.

4. A compression anchoring device for holding the end of a cable in accordance with claim 3 in which said collar is stationary and adjacent said boss.

5. A compression anchoring device for holding the end of a cable in accordance with claim 1 in which the jaw member is molded of a relatively resilient plastic.

6. A compression anchoring device for holding the end of a cable in accordance with claim 1 in which the jaw member is resilient and stamped from sheet stainless steel.

7. A compression anchoring device for holding the end of a cable including in combination a jaw member, a plurality of jaw segments of said jaw member circularly arranged, a cylindrical jaw base joining said segments at one end with each of said segments normally spaced from adjacent segments, a jaw bore provided by said segments, an outer surface of each of said segments, an outwardly directed boss formed on each said outer surface on the remaining end thereof, a tapered portion of each of said outer surfaces providing a decreasing outside diameter of said jaw member in the direction of said boss, a gripping member, a bore of said gripping member receiving said jaw segments between said boss and said jaw base, and said bore of said gripping member being formed with a bore diameter greater than the outside diameter of said jaw member adjacent said boss and less than the outside diameter of said jaw member adjacent said jaw base whereby the diameter of said jaw bore is determined by the relative longitudinal position of said gripping member.

8. A compression anchoring device for holding the end of a cable in accordance with claim 7 in which a longitudinal channel is provided between each of said segments terminating in a separate respective enlarged opening in said jaw base.

9. A compression anchoring device for holding the end of a cable in accordance with claim 8 in which all of said enlarged openings are identical and spaced equally from adjacent openings on a circumference of said jaw base.

10. A compression anchoring device for holding the end of a cable in accordance with claim 1 in which means are provided for fastening said gripping member to a rigid member whereby force applied to said cable within said jaw bore in the longitudinal direction from said jaw base to said boss tending to withdraw said cable from said jaw bore will urge said gripping member relatively toward said jaw base tending to increase the radial forces maintaining said cable in said jaw bore.

11. A compression anchoring device for holding the end of a cable in accordance with claim 10 in which transverse serrations are formed on the surface of each of said segments forming the jaw bore.

12. A compression anchoring device for holding the end of a cable in accordance with claim 11 in which a flexible cylindrical bail is provided for fastening said gripping member to a rigid member with at least one end removably attached to said gripping member.

13. A compression anchoring device for holding the end of a cable in accordance with claim 11 in which a stiff bail is provided for fastening said gripping member to a rigid member with at least one end removably attached to said gripping member.

14. A compression anchoring device for holding the end of a cable in accordance with claim 12 in which first and second holes are provided in said gripping member of substantially equal diameter, and said bail is provided with first and second heads at the ends thereof respectively said heads having greater diameters than said holes with said bail having a diameter less than said holes whereby said bail can be disposed within said holes, and a slot extending from one of said holes to the edge of said gripping member, said slot being sufficiently wide to permit insertion of the bail therein while not wide enough to allow passage of said head therethrough, whereby the end of said bail can be readily removed and operatively attached to said gripping member.

References Cited by the Examiner UNITED STATES PATENTS 876,138 1/1908 Stein. 1,601,255 9/1926 Marra. 1,729,862 10/1929 Becker. 1,757,570 5/1930 Hoerr 248-56 2,210,096 8/ 1940 Pennell 24-126 2,217,978 10/1940 Becker. 2,535,623 12/ 1950 Becker.

WILLIAM FELDMAN, Primary Examiner. B. A. GE'LAK, Assistant Examiner.