US2244482A - Compression joint tool - Google Patents

Description

June 3, 1941. D. L. BAXTER ErAL COMPBESSION JOINT TOOL Filed July 9, .1958 `2 Sheets-Sheet INVEN-roRs D,| .BAxTER BY J.P.BE|S

ATTORNEY Patented June 3,J 1941 commission .vom Toor.

Donald L. Baxter, Rutherford, N. J., and John I.

Reis, Hempstead, N.

Y., assignors to The Western UnionTelegraph Company, N. Y., a corporation of New York New York,

Application July 9, 1938, 'Serial No. )218,470

('Cl. 14n-'113) 7 Claims.

This invention relates to a compression joint tool for compressing electrical connectors, and more particularly to an improved tool for compressing line wire sleeve connectors into intimate clamping contact with the line Awires inserted therein.

For many years it was the practice to splice copper line wires by means of thin-walled copper connectors, commonly called sleeves, into which the line wires were inserted, the sleeves and wires then being given several complete twists by means of tools called sleeve twisters. These connectors had various disadvantages in that the sleeve twisters injured the wire at the point where they gripped the sleeve and consequently the mechanical strength of the wire at the joint was appreciably less than that of the rest of the span, and the sleeves did not set so closely around the wires as to prevent corrosion of the wires and the inside of the sleeves, which corrosion in time caused a marked increase in the electrical resistance of the joints. For these reasons the sleeves were not suitable for high frequency communication circuits which require constant low resistance joints.

In order to overcome the foregoing disadvantages of the twisted sleeve connectors, connectors have been devised which comprise sleeves or tubes into which the Wires are pushed from the opposite ends of the sleeves, the tubes then being rolled, pressed or squeezed by the operator, usually a lineman, until they are in intimate clamping contact with the wires. One type of such connector is shown in the patent to D. L. Baxter, No.-2,062,9B6, issued December l., 1936. The line wire joints, however, are usually made in the field by linemen, oftenunder difficult conditions and without close supervision, and the emcacy of the completed jointsstill depends in large measure upon the skill and degree or careexercised by the linemen when applying pressure to the connecting sleeves. Ii insuilicient pressure is applied the joint does not have the necessary me- Permissible variations of tolerance in sleeve and wire rthan has heretofore been possible.

A further object is -a compression joint tool which, when used with double tube sleeves, produces substantially equal pressures simultaneously on both tubes of the sleeves. An additional object is a tool of the character `described in which'the efficiency of the tool may connection with the accompanying drawings, in

which:

Fig. l is a View in elevation oi the compression joint tool;

Fig. 2 is a view of the tool taken at right angles to Fig. 1, with certain parts broken away;

Fig. 3 is an enlarged view with certain parts broken away, showing the respective positions of various parts when compressing a, sleeve connector;

Fig. 4 shows the positions of certain parts of the tool prior to its engagement with the connecting sleeve and line wires;

Fig. 5 is a view showing a straight line wire lioint made with the compression tool of Figs. 1 to i; and

Fig. 6 is a cross sectional View of a. sleeve connectar utilizing keying particles, showing the line Wires inserted, prior to compression of the sleeves.

Referring to Figs. l to 3, the tool comprises two levers I2 and I3, having outer lever arms in the form, of jaws I2a and Ita with identical pressing grooves` or dies It which receive the tubes oi the sleeve for compressing the sleeve into intimate clamping contact with the line wires inserted therein. The levers l2 and ,I3 are pivotally secured at their iulcrums back of the pressing grooves by curved "straps I5 and closely tting studs I6 that pass through the straps with a light tapping or push t and through the 1evers I2 and I3 with a push t, the studs being t. prevented from coming out by nuts Il, Fig. 2,

screw-threaded on the studs. Washers I8, having keying portions Ia which engage in keyways I'Sa in the studs I6, shown by dotted lines in Fig. 3, are inserted between the nuts and the adjoin-= ing strap t'o facilitate 'pivotal movement of the levers I2 and I3, and to prevent `such pivotal force applied at the handles.

movement from being communicated to the nuts The lever ends of the jaws, i. e., the inner arms of levers I2 and I3, are pivotally connected at 25, to a pair of toggle-jointed handles 2| and 22. The handle 22 has two lugs or ears 22a integral therewith which lugs are spaced apart to receive a lug or ear 2Ia integral with the handle 2|. The lugs 2| a and 22a are pivotally connected by a closely iitting bolt or stud 23, the bolt beingV prevented from turning by a shoulder 28 on the handle 22 which engages the hexagonal head on one end of the bolt. A nut (not shown, but like the nut 29 in Fig. 2) is screw-threaded on the other end of the bolt to keep it from coming out. The lugs and bolt form a tongue-andclevis joint that comprises the knuckle of a toggle between the handles 2| and 22 and the levers I2 and I3.

The handle 2| also has two lugs or ears 2lb which receive the lower end of the lever I2, and

the handle 22 has two lugs or ears 22h which receive the lower end of the lever I3. Studs 25 pass through circular openings in these lugs, and as shown in Fig. 2 each stud has closely fitting portions 25a and 25h that engage circular openings in the lug,` 2lb or 22h through which the stud passes. The studs also have eccentric portions 25c that closely engage circular openings.` in the levers I2 and I3. The extent of throw or pivotal movements of the levers may be adjusted, by rotating the studs 25 and hence the eccentric portions 25e to different positions relative to the levers I2 and I3, to accommodate the closure of the tool to variations in the tolerances of the different sizes of the tool elements; to adjust the amount and distribution of pressure exerted on the sleeve connectors by the dies I4; and to compensate for wear in the bearing surfaces of lthe various parts.

The studs have hexagonal heads, as shown, and shoulders 2l formed on the handles 2| and 22 engage the heads and maintain the studs 25 in their adjusted positions, it being understood that the studs must be pulled out until their heads clear the shoulders 21 in. order to turn the studs and eccentric portions 25o to the desired positions. Nuts 29 prevent the 'studs from coming out, washers 30 being inserted between the nuts and adjoining ears 2 Ib and 22h.

After -tne nuts on the various bolts and studs have been properly tightened, they are punched to lock the nuts in position, indicated 'by the small dotted circles v in Fig. 3. Preferably,` and as shown, the handles 2| and 22 are provided-with grips 3| of rubber or other suitable insulating material.

The construction provides a form of secondary toggle pressure in the dies I4 as a result of the pivotal mounting and shape of the jaws l2a and |3a and the operation of the primary toggle. In Figs. 1 and 2, the various parts of vvthe tool are drawn to scale; these figures in the application drawings show the tool actual size, and in the patent drawings approximately twothirds actual size. The closing of the handies by the operator forces the lever ends of the jaws with a force under direct leverage of approximately 2500 pounds when a. force of .25 pounds is e plied at the handles, and in addition to the direct leverage the spacing of the die impressions I4 relatively close to the center line :r joining the two studs I6 induces an additional mechanical advantage by a reverse toggle action which augments the pressure at the die impressions to over 4000 pounds, this being a gain of over and making it substantially in excess of that obtained by simple leverage. Preferably, the distance from the lowermost portion of the dies I4 to the center line a: is less than one-sixth of the distance between the centers of the studs f I E. It is possible to further increase the die pressure by moving the position of the die im`V pressions still closer to the above mentioned center line, although the die members should be kept far enough away from the center line to obtain a few thousandths of an inch adjustment when the eccentric studs 25 are rotated to obtain such adjustment.

Referring again to Fig. 3, a spring 35 and roller 36 mounted in recessed portions I2b and I3b of the levers I2 and I3 are provided to coordinate the action of the two jaws I2a and I3a and also the dies I4, I4, the position of the spring 35 (slightly compressed) and its supporting roller 36 being below the center line a: when the tool is closed, as at this position the sleeve S itself, being under compression around the wire w, acts to coordinate the jaws and hold them in alignment. When the tool starts tov close, the roller and spring, now under partial compression and rolding the jaws in perfect alignment whle'empty, move downwardly from the position shown in Fig. 4,' the spring compresses further and the fit of spring and roller is tightest when they are in the center line position which is the critical point where the sleeve is first gripped by the dies. As the compression of the sleeve progresses it 'takes up the duty of keeping the jaws in alignment, and when the tool is fully closed, as shown in Fig. 3, thel roller hasV passed over the center line, and the jaws are held in alignment both by the sleeve and the compression left in the spring.

Studs 39 integral with the handles 2| and 22 limit the extent of over-travel of the primary toggle structure, as indicated by the line y' in Fig. 3, the dot-and-dash line y indicating the dead center position of the toggle. It will be noted that as the handles are operated, the toggle structure passes from its open position, shown in Fig. 4, to its dead center position, shown in Fig. 1 and indicated by the line y in Fig. 3, which is the position of predetermined maximum pressure of the tool, and then from y to its nal apart by primary toggle action therebyattaining in. a tool having the parts proportioned as shown, a separating force or pressure on the lever ends of approximately twentytimes the Thus, with a tool which has an overall length of less than `twelve inches, the force applied atthe ha'ndles serves to brina the die endsof the jaws together over-travel position y', as shown in Fig. 3, at

lwhich time the pressure exerted on the sleeve connector begins to decrease since the pivotal action of levers I2 and I3 about their fulcrums I6 is reversed at this time, and therefore the pressure exerted by the tool cannot exceed the f' predetermined maximum pressure obtained in the dead center position of the toggle.

The shape and thickness of the levers I2 andv I3, Figs. 1 and 2, are such as to cause a slight but predetermined deection of the jaws under load, as is indicated by the dot-and-dash line z in Fig. 3, which deection takes place well within theelastic limits of the materials used. This deection of the lever produces parallelism of the jaws I2a and I3a when the jaws are stressed to the pressure required to make a suitable joint,

the tool to make a satisfactory press in either 4 a single or multiple sleeve connector with one movement of the handles, and enables a satisi'actory joint to be made with greater variations oi tolerance in sleeve and wire than has heretoiore been possible.X The tool produces an accurately predetermined maximum pressure on `the sleeve and wire when compressing a joint,l

which pressure is independent of the speed of working the tool or amount of eii'ort exerted by the operator, and by previous adjustment to give the desired pressure when all three pivots 2l,r

25, 25 of thetoggle are in a straight line, i. e., at dead center, the tool operates correctly at all times irrespective of the skill of the operator so long as dead center is reached or passed by the toggle action. The selection of materials and hardness of the parts is such that the smallest and least expensive pieces are subject to the mostjwear, and are, therefore, the easiest to replace, thus securing economical maintenance of the tool at -all times. The provision of a. press iit of the studs I6 into the levers I2 and I3 divides the movable bearing load between the studs and the two straps I5, thereby utilizing the largest available bearing surface, increasing the usable life oi the tool and permitting a lighter and more compact design, yet providing a tool adequatefor the severe service required, which tool is light and properly balanced for use by linemenJ and `therefore may be operated at awkward angles in close quarters.

Fig. shows the completed joint in which the multiple tube sleeve connector s has been compressed at s', s' into intimate clamping contact with the line wires w, w to provide a gas tight joint of constant, low electrical resistance and of mechanical strength sufcient to permanently hold the strain on the line wires. If desired, as shown in Fig. 6, keying particles lc composed of metal harder than that of the sleeve and line wires, may be employed. The keying particles may be applied to the sleeve 'in the manner disclosed in a copending application of Dickie and Wheeler, Ser. No. 49,814, rlled November 14, 1935, now Patent No. 2,149,209, issued February 28.

disposed complementary die portions for receive.l

ing said conductor, means extending between said levers for pivotally securing said levers at their fulcrums, said means causing the die portions to approach each other and compress the conductor received therein when the inner lever arms are rotated in a direction to cause the die portions to approach each other, two handles each having a fulcrum and a first lever arm, means pivotally connecting the fulcrums of said handles to said inner lever arms respectively,`

said handles each having a second lever arm, and means pivotally connecting the second lever arms of the handles together to form an vovertravel toggle joint between the :lulcrums oi the handles, said levers and toggle joint acting to multiply the force exerted on the handles .and cause a predetermined amount of pressure invariably to be exerted on the conductor by the die portions when the handles are operated to their working position for compressing the conductor, said toggle joint preventing pressure from being exerted on the conductor in excess of said predetermined amount by passing to itsv over-travel position as the handles are operated.

2. A compression joint tool for compressing a wire sleeve connector, comprising two levers each having a fulcrum and outer and inner lever arms, the outer lever arms comprising jaws having oppositely disposed complementary dies for receiving a sleeve connector, means extending between said levers for pivotally securing said l levers at their i'ulcrums, said means causing the dies to approach each other and compress the sleeve connector when the inner lever arms are rotated away from each other, two handles each having `a fulcrum and a rst lever arm, means pivotally connectinw the fulcrums or said handles to said inner lever arms respectively, said.V

handles each having a second lever arm, and means pivotally connecting the second lever arms of the handles together to form an overtravel toggle joint between the fulcrums of the handles, said levers and toggle joint acting to enormously multiply the pressure exerted on lthe handles by an operator and cause a predetermined amount of pressure invariably to be exerted on the sleeve connector by the dies, when the handles are lbrought towards each other by the operator, to compress the connector Iinto intimate clamping contact with a wire inserted therein, said toggle joint preventing pressure from being exerted on the sleeve connector in excess of said predetermined amount by passing to its over-travel position as the handles are brought together by the operator.

3. A compression joint tool for compressing a wire sleeve connector, comprising two levers each having a fulcrum and outer and inner lever arms; the outer lever arms comprising jaws having oppositely disposed complementary dies for receiving a sleeve connector, means extending between said levers for pivotally securing said levers at their fulcrums, said means causing the dies to approach each other and compress the sleeve connector when the inner lever arms are rotated away from each other, two handles each having a fulcrum and"a ilrst lever arm, means pivotally connecting the fulcrums of said handles to said inner lever arms respectively, said handles each having a second lever arm extending substantially at a right langle to said rst lever armand means pivotally connecting the second lever arms of the handles together to form an over-'travel toggle joint acting to enormously multiply the pressure exerted on the handles by an operator and cause a predetermined amount of pressure invariably to be exerted on the sleeve connector by the dies, when thetoggle reaches or passes dead center as the handles are brought towards each other by the operator, to compress theconnector into intimate clamping contact with a wire inserted therein, said toggle joint preventing pressure from being exertedon the sleeve connector in excess of said predetermined amount by passing between said levers for pivotally securing said levers at their fulscrums, said means causing the dies to approach each other and compress the sleeve connector when` the inner lever arms are rotated away from each other, two handles each having a fulcrum and a rst lever arm, means pivotally connecting the fulcrums of said handles to said inner l'everms respectively, said handles .each having a second lever arm, means pivotally connecting the second leverarms of the handles together to form atoggle joint between the tulcrums of the handles, said levens and toggle joint acting to enormously multiply the pressure exertedn the handles by an operator and cause a predetermined amount of pessure to be exerted on the sleeve connector by the dies to compress the connector into intimate clamping contact with a wire inserted therein,

and resilient means positioned in and acting on said jaws for maintaining the dies in alignment relativ',` to each other.

5. A compression joint tool for compressing a wire sleeve connector, comprising two levers each having a ulcrum and outer and inner lever arms, the outer lever arms comprising jaws having oppositely disposed complementary dies for receiving and compressing a sleeve connector, means pivotally securing said levers at their fulcrums, said means causing the dies to compress the sleeve connector when the inner lever arms are rotated in a direction to cause the jaws to approach each other, means including handles 'for rotating said inner lever arms, said jaws having apertured portions, and resilient means positioned in said apertured portions and acting on said jaws for maintaining the dies in alignment relative tog-each other.

6. A compression joint tool for compressing a wire sleeve connector, comprising two levers each having a fulcrum iand outer and inner lever arms, the outer lever arms comprising jaws havspring member engaging said apertured portions anda member positioned within said compressible spring member for limiting the extent of deformation of the spring member.

7. A compression joint tool for compressing a wire sleeve connector, comprising two levers each having a fulcrum `and outer and inner lever arms, the outer lever arms comprising jaws having oppositely disposed complementary dies for receiving and compressing a sleeve connector, means including a tie member extending between said levers Afor pivotally securing the levers at their fulorums, said dies being positioned relatively close to the center line passing through said iulcrums, said jaws having complementary apertured portions, a compressible tubular spring member positioned in said apertured portions and acting on said jaws to maintain the dies in alignment relative toteach other, and a circular member positioned within said tubular spring member for. limiting the extent of deformation of the spring member as the jaws are brought into clamping engagement with a sleeve connector.

DONALD L. BAXTER. p JOHN P. REIS.

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