Centered Ferrule For Holding End Loops In Wire Rope

Abstract

A ferrule for holding end loops in wire rope comprises a swageable sleeve having on one end an opening for a single course of rope and on the other end an opening for a double course thereof. The centers of both openings lie on the longitudinal axis of the sleeve. The sleeve is bulged outwardly in the region adjacent the smaller opening to provide a pocket for receiving the dead end of the rope. The smaller opening is defined by a collar having a length predetermined to maintain the live course of the rope in a substantially centered condition. A pair of longitudinal ribs on the inner sidewalls define guideways for guiding the rope within the ferrule.

Description

This invention relates to ferrules for holding end loops in wire ropes and cables.

End loops in wire ropes commonly are formed by passing one end of the rope through a ferrule or sleeve. The section of the rope which has been passed through the ferrule is reversely bent to form a loop, and the dead end passed back into the ferrule in the opposite direction. The ferrule then is swaged upon the two courses of rope received in the ferrule.

In this procedure, it is difficult to thread a stiff and unyielding wire rope through the ferrule openings. It also is difficult to form the end loop in such a manner that during its use the pull is distributed evenly on both sides. Still further, it is difficult to interlock the contiguous courses of wire rope and ferrule to the degree required for heavy duty use of the rope.

It is the general object of the present invention to provide a ferrule which overcomes the foregoing problems in that it guides the wire rope during threading, centers the rope with respect to the ferrule, creates a strong interlock between the ferrule and rope courses, prevents kinking of the rope, and provides equal holding power on both sides.

In its broad aspect, the centered ferrule which accomplishes the above purposes comprises a swageable sleeve of generally elliptical cross section. The sleeve has on one end an opening dimensioned to pass a single course of rope only and on the other end an opening dimensioned to pass two courses of rope arranged side by side in end-loop-forming relation. The center portions of both openings lie substantially on the longitudinal axis of the sleeve.

The sleeve preferably is bell shaped in contour to form a dead end recess on the end adjacent the smaller opening, a central are frictionally gripping the rope courses, and a terminal are adjacent the larger opening which serves a rope-guiding function.

The opening adjacent the smaller end is defined by a collar having a length predetermined to maintain the live course of the rope in a straight, substantially centered condition with respect to the longitudinal axis of the ferrule. This prevents kinking of the rope during swaging and insures even distribution of load during use of the rope.

In the drawings:

FIG. 1 is a longitudinal sectional view of the herein described centered ferrule;

FIG. 2 is a front end view of the ferrule;

FIG. 3 is a transverse sectional view taken along line 3--3 of FIG. 1;

FIGS. 4 and 5 are longitudinal sections illustrating the ferrule in its association with a wire rope threaded therethrough to form an end loop; and

FIG. 6 is a view in elevation of a wire rope end loop including the presently described centered ferrule after swaging.

As shown in the drawings, the ferrule of my invention comprises a sleeve indicated generall at 10 and made of a swageable metal such as steel. The sleeve is designed to receive a wire rope or cable 12 formed into a loop including a running course 12a and a standing course 12b terminating in a dead end.

The ferrule is of a sufficient length to accommdate contiguous courses of wire rope having a length sufficient to form an interlock of the desired strength after swaging.

The ferrule is flat. It has a thickness "T," as defined by two of its side walls 14 sufficient to accommodate a singel course only of wire rope. It has a width "W," as determined by the other two of its sidewalls 16, sufficient to accommodate two courses thereof, i.e., the running course and standing course in contiguous relationship to each other.

The ferrule is open at both of its ends. In one of its ends it has an opening indicated generally at 18. This is of sufficient diameter to accommodate a single course only of the wire rope. It is defined by a collar 20 of sufficient length to center the live course of the wire rope in the first instance and to maintain it centered during swaging and use. The opening 22 at the other of its ends is sufficiently large to accommodate two courses of the rope, side by side.

Side walls 14 of the ferrule preferably are flat. However, side walls 16 are arcuate and bell-shaped in outline to divide the interior into three distinct regions. The region adjacent small opening 18 is bulged outwardly to provide pockets 24, one on each side. These are of sufficient size to permit insertion of the dead end of the wire rope substantially into abutment with the end wall of the ferrule. This insures the development of maximum strength in the interlocked bond between the ferrule and wire rope. The importance of this is illustrated by the fact that in logging applications the ability to inset the dead end of the wire rope by an additional distance of only 1/8 inch increases the holding strength of the loop by 2,000 pounds or more.

The bell-shaped contour of the ferrule also creates a waist, or restricted central area 26. This is sufficiently restricted to create a friction fit between the wire rope and the inner walls of the ferrule in this region. Such a condition is desirable since it maintains the rope in proper position within the ferrule, as the assembly is being inserted into the press preliminary to swaging.

The third region is the enlarged terminal region 28 adjacent opening 22. In this region there are present outwardly flared interior surfaces which assist in guiding the wire rope into the ferrule.

Further to assist in guiding the wire rope into the ferrule and to maintain the courses in proper relation to each other preliminary to swaging, there are provided a pair of central, longitudinally extending interior ribs 30. These divide the interior of the ferrule into two longitudinal passageways, each of which is designed to receive one of the rope courses.

In the application of the ferrule, wire rope 12 is threaded through small opening 18 and out through larger opening 22 on the other end of the ferrule. It is then bent back into itself and the dead end inserted into the ferrule as far as it will go, FIG. 4. As noted, it can be inserted almost completely to the end of the ferrule because of the clearance afforded by pockets 24.

During the threading operation section 28 of the ferrule assists in guiding the rope, as do longitudinal ribs 30.

The assembly in its FIGS. 4 and 5 conditions next is inserted in the swaging press. This is fitted with cylindrical dies which are slightly undersized. It applies sufficient pressure to deform the ferrule into a cylindrical contour matching the dies. This is illustrated in FIG. 7. During the swaging operation, collar 20 serves the important function of maintaining wire rope 12 centered with respect to the ferrule. In view of this fact, and in view of the symmetry of the ferrule, tilting of the ferrule to one side or the other is avoided. Also, during use of the rope in heavy duty applications, the load is applied equally to both sides of the loop thereby correspondingly enhancing its performance.

Claims

Having thus described my invention in preferred embodiments, I claim:

1. A ferrule for holding end loops in wire rope, comprising

a. a swageable sleeve of generally elliptical cross section having on one end an opening dimensioned to pass a single course of rope only and on the other end an opening dimensioned to pass two courses of rope arranged side-by-side in end-loop-forming relation,

b. the center portions of both openings lying substantially on the longitudinal axis of the sleeve,

c. the two opposite side walls defining the thickness of the sleeve being substantially flat,

d. a pair of central, longitudinally extending ribs on the inner surfaces of the two opposite side walls defining the thickness of the sleeve disposed on the longitudinal central plane of the sleeve and terminating inwardly of the opening on said one end of the sleeve and dividing the interior of the sleeve into two adjacent longitudinal passageways each dimensioned to receive one of the respective rope courses side-by-side within the sleeve,

e. the two opposite side walls defining the width of the sleeve being outwardly bulged in the region adjacent the opening on said one end of the sleeve, thereby providing inner pockets dimensioned selectively to receive the dead course of rope in the region adjacent the opening on said one end of the sleeve,

f. the opening on said one end being defined by the collar of length predetermined to maintain the live course of the rope in a substantially centered condition during use of the rope.

2. The ferrule of claim 1 wherein the two opposite side walls defining the width of the sleeve are shaped inwardly to provide a central area of restricted cross section dimensioned to receive the courses of rope side-by-side in frictional engagement with the inner walls of the sleeve, whereby to retain the ferrule thereon preliminary to swaging.

3. The ferrule of claim 1 wherein the two opposite side walls defining the width of the sleeve are outwardly flared in the region adjacent the opening on said other end of the sleeve, thereby providing a guiding area facilitating entry of the rope into the ferrule.

4. A ferrule for end loops in wire rope, comprising:

a. a swageable sleeve of generally elliptical cross section having on one end an opening dimensioned to pass a single course of rope only and on the other end an opening dimensioned to pass two courses of rope arranged side-by-side in end-loop-forming relation,

b. the center portions of both openings lying substantially on the longitudinal axis of the sleeve,

c. the two opposite side walls defining the thickness of the sleeve being substantially flat,

d. a pair of central, longitudinally extending ribs on the inner surfaces of the two opposite side walls defining the thickness of the sleeve disposed on the longitudinal central plane of the sleeve and terminating inwardly of the opening on said one end of the sleeve and dividing the interior of the sleeve into two adjacent longitudinal passageways each dimensioned to receive one of the respective rope courses side-by-side within the sleeve,

e. the two opposite side walls defining the width of the sleeve being bell-shaped in contour and providing

1. inner pockets dimensioned selectively to receive the dead course of rope in the region adjacent the opening on said one end of the sleeve,

2. a central area of restricted cross section dimensioned to receive the courses of rope side-by-side in frictional engagement with the inner walls of the sleeve, and

3. an outwardly flared area adjacent the opening on said, other end to guide the rope courses as they are threaded through the same,

f. the opening on said one end being defined by a collar of length predetermined to maintain the live course of the rope in a substantially centered condition with respect to the longitudinal axis of the ferrule.