US3174323A

US3174323A - Crimping tool

Info

Publication number: US3174323A
Application number: US143151A
Authority: US
Inventors: William R Over
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1960-06-14
Filing date: 1961-10-05
Publication date: 1965-03-23
Anticipated expiration: 1982-03-23
Also published as: DE1515360A1; GB918515A; GB940689A; CH407274A; NL122121C; NL265848A; DE1503135B2; BE604940A; US3053112A; DE1515360B2; DE1503135A1; NL283693A; BE623126A; CH385945A; NL130349C

Description

March 23, 1965 w. R. OVER 3,174,323

CRIMPING TOOL Filed Oct. 5. 1961 3 Sheets-Sheet l March 23, 1965 w. R. OVER CRIMPING TOOL 3 Sheets-Sheet 2 Filed 061;. 5. 1961 March 23, 1965 W. R. OVER CRIMPING TOOL Filed Oct. 5. 1961 3 Sheets-Sheet 3 United States Patent 3,174,323 CRIWHNG TQDL William R. fiver, Union Deposit, Ea, assignor to AMP Incorporated, Harrisburg, Pa. Filed Oct. 5, 1961, Ser. No. 143,151 tClaims. (Cl. 72-412) This invention relates to power actuated tools for crimping loose-piece electrical connectors onto Wires.

Many types of electrical connectors are supplied in loose-piece form, that is the connectors are separated from each other rather than being in the form of a strip or belt. When a loose-piece connector is crimped onto a .wire by means of a hand tool, the operator is faced with the problem of manipulating the tool, the wire and the connector during the crimping operation. Since the operator can hold only two of these items at one time, it is common practice to first insert the wire into the uncrimped connector and then, with one hand, position this uncrimped connector-wire combination between the dies of the tool which is held in the operators other hand. This procedure is not entirely satisfactory for the reason that when the connector is loosely supported on the wire prior to crimping, extreme care must be exercised to ensure that the end of the wire will remain properly located with respect to the connector until the crimping operation is carried out. Furthermore, when the operator follows this procedure he must precisely position the connector between the crimping dies notwithstanding the fact that he does not have direct manual control over the connector during this interval but controls its location only by moving the wire on which it rests.

Some manually held crimping tools incorporate devices for locating and holding the connector on the tool with respect to the dies so that the operator can take the tool in one hand and position the connector in the tool with the other hand in the connector holder. He then has one hand free to grasp the wire and insert it into the uncrimped connector and hold the wire in its proper position while he actuates the tool. These connector holding and locating devices cannot, however, be provided on all types of manually held crimping tools, and are frequently impractical because of the fact that they are not universal, i.e. they cannot be used with different types of connectors.

It is an object of the present invention to provide an improved power assisted crimping tool for crimping loosepiece connectors. A further object is to provide a power assisted crimping tool having means for'holding and loeating [an uncrimped connector on the tool thereby to permit the tool operator to use one hand for holding the tool and the other hand for inserting the wire into the uncrimped connector. A still further object is to provide a power assisted crimping tool having a reciprocable ram with a manually operated take-up device for the ram. A still further object is to provide a connector holding and locating means which grips the ferrule portion of the connector rather than the tongue or other functional end of the connector.

These and other objects of the invention are achieved in a tool comprising a cylindrical housing having a reciprocable ram therein. A normally broken toggle in the housing has one end pivotally connected to the ram and the other end pivoted to a stationary pivot pin .so

that upon straightening of the toggle the ram is moved from aninitial retracted position to:an extended position. A camming block has a surface engageable withthe knee joint of the toggle tostraighten the toggle and (to impart the workingor crimping stroke ,to the ram. The toggle and ram are not directly connected :to the cam ,so that the ram can be moved in the direction of its working 3,174,323 Patented Mar. 23, 1965 stroke independently of the cam. This independent motion of the ram is imparted thereto by means of a slidable finger piece on the tool housing and constitutes the quick take-up arrangement by means of which the movable die on the ram is moved towards the fixed die. In use, the ram is initially moved by this separate finger piece until an uncrimped terminal positioned between the crimping dies is gripped between the dies and the cam is thereafter actuated to impart the final increment of movement to the ram to crimp the terminal. It then becomes necessary to return the ram to its initial position for the next operating cycle of the tool. This is accomplished by me ans of a ram return means comprising a plate which has a flange or shoulder engageable with the ram after it has completed its working stroke to crimp the terminal. This plate is resiliently biased in the direction opposed to the direction of the working stroke of the ram and is moved in the direction of the working stroke by the cam itself. The arrangement is such that when the resiliently biased plate is moved by the cam, it engages the ram and during the return stroke returns the ram to its initial position. At the end of the return stroke, the plate is automatically disengaged from the ram thereby releasing it for movement through the finger piece during the next operating stroke of the tool. In the drawing:

FIGURE lis a perspective view of a tool in accordance with the invention.

FIGURE 2 is a central longitudinal sectional view of the tool of FIGURE 1 showing the positions of the parts at the beginning of the operating cycle.

FIGURE 3 is a view similar to FIGURE 2 but showing the positions of the parts after the manually actuated quick take-up device has been operated to move the ram upwardly for a portion of the stroke.

FIGURE 4 is a fragmentary side vview similar to FIG- URE 2 but showing the return plate and the latch plate by means of which the ram is retracted.

FIGURES 5 and 6 are views similar to FIGURE 4 but showing the relative positions of the parts at successive stages of the operating cycle.

FIGURE 7 is a view taken along the lines 7--7 of FIGURE 6.

FIGURE 8 is a perspective view of a return plate which forms part of the invention.

FIGURE 9 is a perspective view of a latch plate which cooperates with the return plate to effect retraction of the ram; and

FIGURE 10 is a perspective view of a terminal of a type adapted to be crimp'ed by the tool of FIGURE 1.

The embodiment of the invention disclosed herein is provided on .a power actuated manually held crimping tool of the general type disclosed and claimed in thecopending application of Martin L. .Klingler, Serial No. 36,023, filed June 14, 19.60 for Compressing Tool, which became Patent Number 3,053,112. Tools of this type oversized opening 8 is provided in the cylinderhead .6

and a ram formed .in two threaded together extensible parts 19, .12, eXtends through this opening. The exter- :nal surface of head ,6 has a pair of .upstandingears 14- which receive the lower arm 18 of a generally C-shaped frame 16. The lower arm .18 has an opening therein which conforms to the cross sectional shape of the ram and guides the ram along a rectilinear path to move the a crimping dies relatively towards and away from each other. The movable crimping dies 28 are mounted on the ram 12 by means of a die holder 24 and the fixed crimping dies 30 are mounted on the upper arm 20 of frame 16 by means of a die holder 26. Dies of the type shown are adapted to crimp the cylindrical ferrule portion 32 of a terminal onto the end 36 of a wire 38. This connector has a functional erid which comprises a ring tonque 34 in the disclosed embodiment but which may take any one of a variety of alternative forms.

The lower end 10 of the ram is pivotally connected to a toggle comprising a pair of

links

40, 42 having their ends commonly connected on a pivot pin 44. The

links

40, 42 each comprise two parallel side bars integrally joined at their ends. The two links have their common ends fitting within each other at the common pivotal axis 44. A cam follower or roller 46 surrounds pivot pin 44 for cooperation with a camming block as described below. The lower end of the toggle linkage, that is the lower end of the link 40, is pivotally mounted on a pin 48 which is mounted in the sidewalls of the cylinder head extension. The upper end of the link 42 is pivotally connected at 50 to the lower end of the ram section 10. It will be apparent that when the toggle is broken the ram is in its retracted position and that when the toggle is straightened the ram is in its extended position. Straightening of the toggle thus imparts the working stroke to the ram during which the connector is crimped.

A block 52 is disposed between the opposed sidewalls 5 of the cylinder head extension and has an arcuate camming surface 54 on its side which faces the pivot pin 44. Upon relative upward movement of this block, the toggle is straightened by the face 53 of the cam and then by the cam surface 54 thereby to impart the crimping force or thrust to the ram. The lower end of block 52 is centrally slotted at 56 and a link 58 extends into this slot and is pivoted thereto at 59. This link extends through an oversized opening in a separator plate 62 and is pivoted at its opposite end to a piston 60 contained within the lower part of the housing 2. The piston is normally biased downwardly toward the lower end of the housing by means of a spring 66 which is interposed between plate 62 and the recess in the piston 60. The separator plate 62 referred to above bears against the lower end of'the

cylinder head extension

5, 7 and is maintained in position by the force of the spring 66.

Movement of the block 52 is controlled by two pairs of

links

68, 70 mounted on each side of the block and externally of the sidewalls 5 on the cylinder head exten sion. The links 68 are pivotally connected at one end to the pin 48 on which the lower end of the toggle is pivotally mounted. Links 63 are pivotally connected to the block-52 by means of a pin 72 which extends through the block and through the recess or slot 56. The links 70 are pivotally mounted on fixed pins 76 in the opposed sidewalls 5. It will be noted that the pins 76 do not extend through the cylinder head extension since this space between sidewalls 5 must be left unobstructed for the movement of the

ram toggle

40, 42. The opposite ends of the links 70 are pivotally connected to a pivot pin 74 which extends through the upper end of the block 52. It will be apparent from the foregoing that upon upward movement of the piston 60, the block 52 travels along an arcuate path from the position of FIGURE 3 and the cam surface 54 is brought into engagement with the cam follower 46 to impart the crimping force to the rann Advantageously, a rack bar 78 is held against the lefthand side of block 52 as viewed in the FIGURES 4-6 by means of a plate 80 secured to this side of the block. The rack bar has teeth intermediate its ends for engagement with a pawl 82 pivoted on pin 72 in slot 56 of the block. This pawl is biased downwardly as viewed in the drawing in a counterclockwise direction by means of a spring 84 and the end of the pawl is so shaped as to permit it to be reversed with respect to the teeth on the rack bar in either of two

depresisons

86, 88 in the bar on each side of the teeth. The arrangement is such that after movement of the block along its arcuate path has commenced during a crimping stroke, the direction of movement of the parts can not be reversed until the stroke has been completed thereby preventing partial crimping of a connector as is explained in the aboveidentified Klingler Patent Number 3,053,112.. It is desirable to provide a leaf spring 90 in the cylinder head extension with an end bearing against the link 40 so that the

toggle

40, 42 will be partially broken by this spring during the return stroke of the tool when the cam follower has been freed from pressure.

It will be apparent from the foregoing description that the block 52 and the toggle for the

ram

10, 12 are not directly connected to each other and that final straightening of the toggle is accomplished only by the cam surface 54. Means are provided for substantially, but not fully, straightening this toggle and driving the ram upward through a substantial portion of its stroke to grip the terminal barrel 32 between the crimping dies. This means comprises a finger piece 92 slidably mounted in a guide slot 96 on the surface of housing 2. This finger piece extends through aligned slots 94 in the housing and the cylinder head extension wall 7 and is secured to the lower end of ram 10 by means of a fastener 93. When the tool is held in the hand, this finger piece can be pushed upwardly by the thumb of the operator to drive the ram upwardly through a portion of the cycle until the ferrule portion of the terminal is gripped between the dies. Thereafter, the end of the wire is positioned in the terminal, the air supply system is actuated by trigger 9 and compressed air is admitted into the lower endof the housing 2 to drive the piston 60 upwardly. As the block 52 moves along its arcuate path, the cam surface 54 straightens the toggle linkage on the ram and imparts the crimping force to the dies.

When the compressed air is exhausted from the lower end of the housing, the pistonand block 52 move relatively downwardly under the influence of spring 66. The ram is automatically returned to its retracted position by means of a pair of plates 98 having generally

parallel sides

100, 102 and having an ear 104 struck out from their upper ends as viewed in the drawing. A triangular notch 106 is provided at the opposite ends of the plate and a toe 108 extends from one side of. this opposite end while an extension 110 projects fromthe other end adjacent to the ear 104. A cam surface 112 extends obliquely from the side of extension 110 to surface 100. These plates are positioned against the outside surfaces of the

links

68 and 70 with the ears at the upper end of the toolfacing outwardly from the sidewalls. Latch plates 114 are pivotally mounted on each side of these plates on the pivot pin 50, these latch plates having elongated slots 116 therein to permit movement relative to the fixed pivot pins 48, 76. A shoulder 117 is provided in each latch plate adjacent to the pin 50- for engagement with the ears 104 of the return plates 98 in a manner described below.

The return plates are held in position by means of springs 118 which are secured at one end .to brackets 120 on separator plate 62 and at their opposite ends 122 to the ears 104. The apices of the notches 106 are adapted to be engaged by pins 124 which are provided on the links In use, parts will normally be in the position of FIG- URES 2 and 4 with theram in-its retracted position. The operator first holds or positions the ferrule portion 32 of the terminal againstthe fixed die 30 and moves the finger piece upwardly until the ferrule of the terminal is gripped between the dies 28,: 30 as shown in FIGURE 1. FIGURES 3 and 5 show the relative positions of the parts within the housing 2 after this upward movement of the finger piece by the operator. The operator can then release his grip upon the terminal 32.

and grasp the wire 38 in his other hand and position its stripped end 36 in the ferrule of the terminal. The operator then actuates the air supply system by depressing trigger 9 to drive the block 52 along its arcuate path and impart the final increment of motion to the ram for its working stroke thereby to crimp the terminal. During this working stroke of the ram, the plates 98 are pushed relatively upwardly bythe drive pins 124 until the projecting ears reach the shoulders 117. The plates then move laterally until these areas abut the shoulders on each of the latch plates 114 as shown in FIGURE 6. The motion of the plates 98 during this portion of the cycle is partially controlled by the spring 118. The brackets 120 to which the lower ends of these springs are secured are not centrally located on the separator plate 62 but are slightly displaced from the center plane of the tool. The plates are thus biased relatively towards the latch plates 114 and as soon as the ears 104 encounter the shoulder 117, the plates are moved laterally until these ears abut the shoulders. This lateral movement of the plates 93 is thus brought about by a limited clockwise swinging of the plates (as viewed in FIGURES 5 and 6) about the pins 124- which serve as pivotal axes.

After completion of the crimping operation, the lower end of the cylinder is exhausted and the piston 60 returns to its retracted position under the influence of the spring 66. Upon retraction of the piston 6% the camming block 52 is also retracted and returned to its original position and the pins 124 move downwardly from the position of FIGURE 6 to the position of FIGURE 4. When the pins 124 move downwardly and away from the plates 98, these plates are free to move downwardly under the influence of the springs 118 and the interengagement of the ears 104 of plates 98 and shoulders 117 of the latch plates 114 causes the plates 98 to pull the latch plates 114 downwardly from the position of FIGURE 6 to the position of FIGURE 4. The ram 12 is also moved downwardly since it is connected to the plates 114 by the pin 50. During the final portion of the downward movement of

plates

93 and 114, the camming surfaces 112 of the plates 98 move against the pins 76 causing the plates 93 to swing counterclockwise about their lower ends. This swinging motion of the plates 98 brings about the disengagement of the ears 104 from the shoulders 117 of the latch plates so that the plates 98 can'return to their initial position (FIGURE 4) with the pins 124 seated in the apices of the notches 1%. It will be under stood that the finger piece 92 is pulled downwardly with the ram during this return stroke.

I claim:

1. In a compressing tool comprising, a housing, a cam in said housing, said cam being pivotally secured to one end of a link means, said link means being pivotally secured to said housing at its opposite end, means for moving said cam along an arcuate path defined by said link means, a toggle mechanism in said housing having one end pivotally mounted on a fixed axis and having a knee joint in engagement with said cam, a ram, the other end of said toggle being pivotally secured to said ram whereby, upon movement of said cam, said toggle is straightened out and said ram is moved, the improvement comprising: a finger piece for moving said ram and strightening said toggle independently of said cam thereby to provide a quick take-up for said ram, and ram return means acting on said ram independently of said cam to return said ram after crimping, said ra-m return means comprising a plate resiliently biased in the direction of return movement of said ram, said plate having means for engagement with said link means during movement of said cam in the direction of movement of the Working stroke of said ram, and said plate having hook means for engagement with said ram after the conclusion of movement of said plate in the direction of movement of the working stroke of said ram.

2. In a compressing tool comprising, a housing, a cam in said housing, said cam being pivotally secured to one end of a link means, said link means being pivotally secured to said housing at its opposite end, means for moving said cam along an arcuate path defined by said link means, a toggle mechanism in said housing having one end pivotally mounted on a fixed axis and having a knee joint in engagement with said cam, a ram, the other end of said toggle being pivotally secured to said ram whereby, upon movement of said cam, said toggle is straightened out and said ram is moved in a working stroke, the improvement comprising: a finger piece for moving said ram and straightening said toggle independently of said cam thereby to provide a quick take-up for said ram during said working stroke, and resiliently biased ram return means engageable with said ram after completion of said working stroke to return said ram to its initial position independently of said cam, said resiliently biased ram return means being disengageable from said ram after said return stroke to permit use of said finger piece without restraint by said ram returns means in the next working stroke.

3. In a compressing tool comprising, a housing, a ram in said housing, a normally broken toggle having one end pivotally connected to said ram whereby, upon straightening of said toggle said ram is moved from an initial retracted to an extended position, cam means engageable with said toggle to straighten said toggle and impart said working stroke to said ram, the improvement comprising: a slidable finger piece for moving said ram independently of said cam thereby to provide a quick take-up for said working stroke of said ram, and ram return means engageable with said ram at the end of said working stroke to return said ram to said initial position, said ram return means being resiliently biased in the direction of the return stroke of said ram and being disengageable from said ram at the end of said return stroke thereby to permit movement of said ram by said finger piece without restraint by said ram return means during the next operating cycle of said tool.

4. A compressing tool for electrical connectors comprising, a housing, a ram in said housing movable, during a working stroke, from a retracted position to an extended position and, during a return stroke, to said retracted position, a movable crimping die on said ram, a fixed crimping die cooperable with said movable die to crimp an electrical connector, a finger piece slidable along said housing in the direction of movement of said ram, said finger piece being connected with said ram whereby, upon movement of said finger piece, said ram is moved thereby to provide a quick take-up of a substantial portion of said working stroke of said ram, power means in said housing acting on said ram for moving said ram through the terminal portion of said working stroke, and resiliently biased ram return means for returning said rain to said initial position, said ram return means being automatically engageable with said ram upon completion of said working stroke and being automatically disengageable from said ram upon completion of said return stroke whereby said ram is free to be moved by said finger piece without restraint by said ram return means during the next operating cycle of said tool.

5. In a compressing tool comprising a housing, a cam in said housing, said cam being pivotally secured to one end of a link means, said link means being pivotally secured to said housing at its opposite end, means for moving said cam along an arcuate path defined by'said link means, a toggle mechanism in said housing having one end pivotally mounted on a fixed axis and having a knee joint in engagement with said cam, a ram, the other end of said toggle being pivotflly secured to said ram whereby, upon movement of said cam, said toggle is straightened out and said ram is moved, the improvement comprising: a plate disposed beside said cam, resilient means normally biasing said plate in a direction opposite to the direction of movement of said ram when said toggle is straight- 7 ened, means acting between said link means in said plate for moving said plate in the direction of movement of said link means during straightening of said toggle, latch means on the leading end of said plate engageable with said ram at the conclusion of arcuate movement of said link means and after said toggle has been straightened whereby said toggle is broken and said ram is retracted under the influence of said resilient means, said latch means being automatically disengageable from said ram after return of said ram to its initial position and after breaking of said toggle, and a finger piece for moving said References Cited in the file of this patent UNITED STATES PATENTS 2,467,020 Fischer Apr. 12, 1949 2,887,916 Freedom May 26, 1959 3,053,112 Klingler Sept. 11, 1962

Claims

1. IN A COMPRESSING TOOL COMPRISING, A HOUSING, A CAM IN SAID HOUSING, SAID CAM BEING PIVOTALLY SECURED TO ONE END OF A LINK MEANS, SAID LINK MEANS BEING PIVOTALLY SECURED TO SAID HOUSING AT ITS OPPOSITE END, MEANS FOR MOVING SAID CAM ALONG AN ARCUATE PATH DEFINED BY SAID LINK MEANS, A TOGGLE MECHANISM IN SAID HOUSING HAVING ONE END PIVOTALLY MOUNTED ON A FIXED AXIS AND HAVING A KNEE JOINT IN ENGAGEMENT WITH SAID CAM, A RAM, THE OTHER END OF SAID TOGGLE BEING PIVOTALLY SECURED TO SAID RAM WHEREBY, UPON MOVEMENT OF SAID CAM, SAID TOGGLE IS STRAIGHTENED OUT AND SAID RAM IS MOVED, THE IMPROVEMENT COMPRISING: A FINGER PIECE FOR MOVING SAID RAM AND STRIGHTENING SAID TOGGLE INDEPENDENTLY OF SAID CAM THEREBY TO PROVIDE A QUICK TAKE-UP FOR SAID RAM, AND RAM RETURN MEANS ACTING ON SAID RAM INDEPENDENTLY OF SAID CAM TO RETURN SAID RAM AFTER CRIMPING, SAID RAM RETURN MEANS COMPRISING A PLATE RESILIENTLY BIASED IN THE DIRECTION OF RETURN MOVEMENT OF SAID RAM, SAID PLATE HAVING MEANS FOR ENGAGEMENT WITH SAID LINK MEANS DURING MOVEMENT OF SAID CAM IN THE DIRECTION OF MOVEMENT OF THE WORKING STROKE OF SAID RAM, AND SAID PLATE HAVING HOOK MEANS FOR ENGAGEMENT WITH SAID RAM AFTER THE CONCLUSION OF MOVEMENT OF SAID PLATE IN THE DIRECTION OF MOVEMENT OF THE WORKING STROKE OF SAID RAM.