Swageless turnbuckle assembly

Abstract

A cable gripping apparatus comprising a plurality of jaw members, each jaw member being tapered on an outer surface thereof from a larger first end to a smaller second end, said plurality of jaw members being configured to receive and grip a cable therebetween. A cylindrical collar having external threads and a tapered internal bore is receivable of the tapered jaw members in the tapered internal bore. A cylindrical turnbuckle body having a threaded bore is receivable of the threaded cylindrical collar entirely within the turnbuckle bore. The cylindrical collar, plurality of jaw members, and cable gripped therewithin define collectively a collar sub-assembly receivable within the turnbuckle bore. When the turnbuckle body is rotated, the collar sub-assembly is moved axially within the threaded bore of the turnbuckle body, thus changing the tension in the cable.

Claims

1. A cable gripping and tensioning apparatus comprising: a) a plurality of jaw members, each jaw member being tapered on an outer surface thereof from a larger first end to a smaller second end, said plurality of jaw members being configured to receive and grip a cable therebetween; b) a cylindrical collar having first and second free ends and having external threads between said first and second free ends and a tapered internal bore therein receivable of said plurality of tapered jaw members in said tapered internal bore; and c) a turnbuckle body having a threaded bore receivable of said threaded cylindrical collar within said threaded bore, wherein said plurality of jaw members further comprise a circumferential groove formed in said outer surface thereof and receivable of an O-ring, wherein tension exerted on said cable urges said plurality of jaw members into locking contact within said tapered internal bore of said cylindrical collar, wherein said threaded bore of said turnbuckle body is longer than said threaded cylindrical collar such that both of said first and second free ends of said threaded cylindrical collar may be contained simultaneously within said threaded bore of said turnbuckle body, wherein tension in said cable can be varied by axial movement of said collar within said turnbuckle body at any time while said cable is secured in said collar by said jaw members, wherein said cylindrical collar, said plurality of jaw members, and a cable gripped therewithin define collectively a collar sub-assembly receivable within said threaded turnbuckle bore, and wherein rotation of said turnbuckle body causes said collar sub-assembly to be moved axially within said threaded bore of said turnbuckle body to vary tension in said cable.

2. A cable gripping apparatus in accordance with claim 1 further comprising ridges in said inner bore of said collar configured to engage said outer surface of at least one of said jaw members.

3. A cable gripping apparatus in accordance with claim 1 wherein said plurality of jaw members cooperatively define an axial bore therewithin.

4. A cable gripping apparatus in accordance with claim 3 wherein said axial bore is provided with features to assist in gripping said cable.

5. A cable gripping apparatus in accordance with claim 1 further comprising at least one pawl formed in said collar and configured to engage a portion of at least one of said jaw members.

6. A method for changing tension in a cable deployed between two fixed points, comprising the steps of: a) providing a cable gripping and tensioning apparatus including a plurality of jaw members tapered on an outer surface thereof and configured to receive and grip a cable therebetween, a cylindrical collar having first and second free ends and having external threads and a tapered internal bore receivable of said tapered jaw members, and a turnbuckle body having a threaded bore receivable of said threaded cylindrical collar entirely within said threaded bore; b) securing a first end of said cable to one of said fixed points; c) securing an end of said turnbuckle body to the other of said fixed points such that said turnbuckle body is axially rotatable; d) inserting the second and opposite end of said cable axially into said jaw members within said turnbuckle body; and e) rotating said turnbuckle body to cause said jaw members to grip said cable and said cylindrical collar to move axially within said turnbuckle body, thereby changing tension in said cable.

Description

DESCRIPTION OF THE DRAWINGS

(1) The foregoing and other objects, features, and advantages of the invention, as well as presently preferred embodiments thereof, will become more apparent from a reading of the following description in connection with the accompanying drawings in which:

(2) FIG. 1 is an exploded perspective view of a first embodiment in accordance with the present invention;

(3) FIG. 2 is a longitudinal cross-sectional view of a portion of the embodiment shown in FIG. 1, showing a cable inserted into the jaw members, and the jaw members inserted into the collar;

(4) FIG. 3 is a detailed cross-sectional view taken from Circle 3 in FIG. 2, showing the relationship among the O-ring, collar, and jaw members;

(5) FIG. 4 is an assembled perspective view of the present invention, including a sealing cap not previously shown;

(6) FIG. 5 is a longitudinal cross-sectional view of the embodiment shown in FIG. 4;

(7) FIG. 6 is a side elevational view of a portion of a second embodiment in accordance with the present invention;

(8) FIG. 7 is a longitudinal cross-sectional view of the second embodiment taken along the line A-A in FIG. 6;

(9) FIG. 8 is a detailed cross-sectional view of a portion of the second embodiment shown in FIG. 7;

(10) FIG. 9 is a side elevational view of a portion of a third embodiment in accordance with the present invention;

(11) FIG. 10 is a longitudinal cross-sectional view of the third embodiment taken along the line A-A in FIG. 9;

(12) FIG. 11 is a detailed cross-sectional view of a portion of the third embodiment shown in FIG. 10;

(13) FIG. 12 is a side elevational view of a portion of a fourth embodiment in accordance with the present invention;

(14) FIG. 13 is a longitudinal cross-sectional view of the fourth embodiment shown in FIG. 12; and

(15) FIG. 14 is a detailed cross-sectional view of a portion of the fourth embodiment shown in FIG. 13.

DETAILED DESCRIPTION OF THE INVENTION

(16) FIGS. 1 through 14 illustrate various embodiments of the present invention in which a novel attachment and tensioning apparatus 10 for use with, e.g., a cable railing system, is shown.

(17) Referring now to FIGS. 1 through 5, a first embodiment 10 in accordance with the present invention comprises a plurality (two shown) of jaw members 12,14 having a larger first end 16 and a smaller second end 18. Optionally, jaw members 12,14 include a circumferential groove 20 for receiving an optional O-ring 22. O-ring 22 serves to hold jaw members 12,14 in close proximity to each other for ease of installation of the jaw members into tapered bore 32 of cylindrical collar 30. Jaw members 12,14 cooperate to define an internal bore 24 with optional features 26 therein to assist in gripping cable 28. Cylindrical collar 30 includes external male threads 34. A turnbuckle body 40 is provided with internal female threads 42 in bore 44 that match threads 34. Collar 30 is threaded into turnbuckle body 40 and is adapted to be received completely inside of turnbuckle body 40.

(18) In a first method of operation, optional O-ring 22 is placed in groove 20 of jaw members 12,14. Cable 28 is placed into collar bore 32. Jaw members 12,14 are placed on cable 28 and inserted into collar bore 32, defining a collar sub-assembly 31 that itself is threaded into bore 44 of turnbuckle body 40.

(19) In a second method of operation, jaw members 12,14 are inserted into collar bore 32, and collar 30 is threaded into turnbuckle body 40. The apparatus is now ready to receive an end of cable 28.

(20) The first and second methods of operation arrive at the same status wherein the cable is being gripped by the jaw members within the collar within the turnbuckle body. To adjust the length and tension of cable 28, turnbuckle body 40 is rotated either clockwise or counterclockwise such that collar sub-assembly 31 is moved axially within turnbuckle body 40. Collar sub-assembly 31 is held completely within turnbuckle body 40.

(21) Optionally, cap 50 may be installed onto cable 28 via a central aperture in the cap prior to either of the above assembly procedures and then threaded into turnbuckle body 40 to seal cable attachment and tensioning apparatus 10.

(22) Referring now to FIGS. 6 through 8, in a second embodiment 231 of a collar sub-assembly in accordance with the present invention, collar 230 includes internal ridges 250 that grip jaw members 12,14 to hold them in place and prevent them from sliding axially out of collar 230 during assembly.

(23) Referring now to FIGS. 9 through 11, in a third embodiment 331 of a collar sub-assembly in accordance with the present invention, collar 330 includes a circumferential groove 360 matable with a corresponding groove 320 in jaw members 312,314. When jaw members 312,314 are inserted into collar 330, O-ring 322 is seated within groove 320/360 to hold jaw members 312,314 in place during assembly.

(24) Referring now to FIGS. 12 through 14, in a fourth embodiment 431 of a collar sub-assembly in accordance with the present invention, collar 430 includes a pawl 470 and the jaw members 412,414 include an external ridge 472. Pawl 470 engages with external ridge 472 when jaw members 412,414 are inserted into collar 430 to prevent jaw members 412,414 from sliding axially out of collar 430 during assembly.

(25) From the foregoing description, it will be apparent that there has been provided an improved method and apparatus for attaching and tensioning a cable. Variations and modifications of the herein described method and apparatus, in accordance with the present invention, will undoubtedly suggest themselves to those skilled in this art. Accordingly, the foregoing description should be taken as illustrative and not in a limiting sense.