US3091275A

US3091275A - Crimping machine

Info

Publication number: US3091275A
Application number: US5044A
Authority: US
Inventors: Charles R Mentzer
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1960-01-27
Filing date: 1960-01-27
Publication date: 1963-05-28
Anticipated expiration: 1980-05-28
Also published as: GB912066A; DE1210060B; NL121618C; CH411082A

Description

y 8, 1963 c. R. MENTZER 3,091,275

CRIMPING MACHINE Filed Jan. 27, 1960 e Sheets-Sheet 1 INVENTOR. CHARLES R. HENuER May 28, 1963 c. R. MENTZER 3,

CRIMPING MACHINE Filed Jan. 27, 1960 s Sheets-Sheet 2 INVENTOR. CHARLES R. NENTZER y 8, 1963 c. R. MENTZER 3,091,275

CRIMPING MACHINE Filed Jan. 27. 1960 6 Sheets-Sheet 3 4 INVENTOR.

E 1; CHARLES R. NENTZER y 8, 1963 c. R. MENTZER 3,091,275

CRIMPING MACHINE Filed Jan. 27, 1960 6 Sheets-Sheet 4 INVENTOR. CHARLES R. NENTZER m ym im May 28, 1963 Filed Jan. 2'7, 1960 C. R. MENTZER CRIMPING MACHINE 6 Sheets-Sheet 5 INVENTOR. CHARLES R. MENTZER M W M May 28, 1963 c. R. MENTZER CRIMPING MACHINE 6 Sheets-Sheet 6 Filed Jan. 27, 1960 INVENTOR. Camus RMENTZER 3,091,275 CRIMPING MACIWE Charles R. Mentzer, Harrisburg, Pa., assignor to All 1P Incorporated, Harrisburg, Pa. Filed Jan. 27, 1960, Ser. No. 5,044 Claims. (Cl. 153-1) This invention relates to machines for crimping connectors or terminals onto the ends of wires.

An object of the invention is to provide an improved apparatus for feeding a succession of terminals or connectors to a crimping station and crimping the leading.

connector onto a wire. A further object is to provide a crimping apparatus having an improved wire stripping and positioning means. A still further object is to provide a crimping apparatus which is particularly adapted to apply relatively small connectors onto extremely small diameter conductors. A still further object is to provide an improved apparatus for crimping open-U type connectors and having means for bending the sides of the connector inwardly and for subsequently crimping the connector by application of a compressive force to the inwardly bent sides.

These and other objects are achieved in a preferred embodiment of the invention comprising a bell crank lever pivoted at its apex and having a crimping die secured to the end of one of its arms. The other arm of the bell crank has a resilient connection with a reciprocable rod so that as the rod moves in a first direction, the crimping die is moved relatively towards a fixed crimping anvil. Mounted on each side of the bell crank by means of a lost motion connection are a pair of levers having bending arms on their ends. These bending arms, upon arrival at the crimping die, are adapted to move relatively towards each other thereby to bend the upstanding sidewalls of a U-shaped connector inwardly and to fold these sidewalls over a wire disposed within the connector. The bending arms of these levers then move apart and the crimping die descends and applies a compressive force to the connector to complete the crimping operation. The preferred embodiment is adapted to feed and to crimp connectors in strip form and to this end provides a feeding means actuated by the above mentioned reciprocaole rod so that a single connector, the leading connector of a strip, is fed to the crimping anvil during each cycle of operation. In order to shear this leading connector from the strip and to trim the wire portion which extends beyond the connector after crimping, there are provided shears movable in planes adjacent the crimping anvil and actuated by the Ieciprocable rod which actuates the bell crank. In order to strip the end of the wire there are provided a pair of abrasive wheels adjacent the crimping anvil so that when the operator positions the Wire in the uncrimped terminal with its end extending beyond the connector, the end is caught in these wheels and the insnlation removed therefrom. The operator can then withdraw a portion of the wire from the wheels so that a stripped section thereof rests within the connector and this stripped section is crimped and held by the connector.

In the drawing:

FIGURE 1 is a perspective view of a preferred embodiment of the invention;

FIGURE Q is a perspective view showing a strip of connectors and showing a crimped connector on the ends of a pair of wires;

FIGURE 3 is a perspective view showing a bell crank lever and a crimping means thereon and the pneumatic piston-cylinder which actuates the bell crank which forms part of the preferred embodiment;

FIGURE 4 is a sectional view showing the preferred embodiment at the beginning of a crimping cycle;

$391,275 Patented May 28, 1963 FIGURES 5 and 6 are views similar to FIGURE 4 but showing the progressive stages of the crimping cycle and illustrating the movement of the parts during the cycle;

FIGURES 7, 8, 9 and 10 are frontal views of the crimping die and the bending arms and illustrating the relative positions of these parts during the crimping cycle;

FIGURE 11 is a frontal view showing the feed mechanism and the crimping area;

FIGURE 11A is a view taken along the line 11-41 of FIGURE 11;

FIGURE 12 is a view taken along the line 12-12 of FIGURE 11;

FIGURE 13 is a perspective view showing the strip shearing means and the wire shearing means;

FIGURE 14 is a fragmentary perspective view showing the actuating linkage for the two shearing means; and

FIGURE 15 is a view taken along the lines 15--15 of FIGURE 5.

The disclosed embodiment of the invention is adapted to crimp connectors in strip form as shown in in FIGURE 2 onto the ends of wires. The strip of FIGURE 2 comprises a tape of plastic material 86, such as Mylar (polyethyleneterephthalate) to which connectors 88 are attached, as by an adhesive, at regularly spaced intervals. The particular connector disclosed is a simple trough-like open-U terminal having one of its sidewalls relatively higher than the other sidewall and is particularly intended to join an extremely fine (e.g. 0.002" diameter) coil wire to a lead wire which is relatively much 'heavier. In use, the two wires are placed within the connector and the sidewalls are folded over each other and crimped. Thereafter, the plastic tape is cut and, in the case of connections between coil wires and lead wires, the tape is positioned against the coil. The cut section of tape with the crimped connection thereon is then secured to the coil by means of an additional piece of adhesive tape.

The preferred embodiment of the invention is mounted in a frame comp-rising a base 2 having a pair of parallel spaced apart webs or flanges 4, 6 which support a top plate 8. This top plate does not rest directly on the tops of the webs but is hinged thereto as shown at '10 and is resiliently urged downwardly in the front portion of the machine against a stop 14 by means of a coil spring 12. It will be understood that a counterpart hinge to the hinge 10 is provided on the opposite side of the machine from the side shown in FIGURE 1. Top plate 8 is cut away as shown at 16 and a bell crank 18 is positioned in this cut away section and between the webs 4, 6. This bell crank is pivotally mounted at its apex on a pin 20 which is supported by ears 22 which extend from a support block 24 (FIGURE 3) contained between and secured to the webs 4, 6.

A first arm 26 of the bell crank has a crimping die 28 secured to its end and a second arm 30 has an enlarged end 32 through which passes a rod extension 33 of a piston rod 34 which, in turn, extends from a pneumatic piston cylinder 36. The end of arm 36 of the bell crank is held between a bar 38 'on piston rod extension 33 and a washer 40. This washer is resiliently biased against bar 38 by means of a coil spring 42, on the end of the rod extension which is retained in place by a nut '44. This arrangement permits the rod 34 and extension 33 .to move rightwardly during a portion of its stroke independently of bell crank arm 30 as is explained below. In order to prevent rightward or counterclockwise movement of the :arm 3% beyond the desired point, there is provided a stop 46 on the base 2 which is adjustably clamped by means of a fastener 43 extending through the :base and into a threaded opening in the stop block. An adjusting screw 50 extends through the front plate of the apparatus and into a threaded opening in the stop block 46. This 3 adjusting screw is threaded through the front plate at 52 so that upon loosening of fastener 48 and rotation of screw 52, the stop can be adjusted towards and away from the front of the apparatus thereby to vary the stroke of the bell crank.

A pair of bending arms 56 are disposed on each side of crimping die 28 and are secured at their upper ends to the ends of levers 58. These levers are clamped intermediate their ends against flat surfaces 62 on the opposite sides of the bell crank by means of spring washers 63 and a bolt 64 which extends through circular openings in the levers and an arcuate slot 66 in the bell crank. This arrangement permits 'aboth relative motion oat the bell crank with respect to the levers and movement of thebell crank independently of the levers. The levers additionally are pivotally mounted on pin 20 and have end portions 61 which extend rearwardly beyond the bell crank and are secured to a block 60 so that they move in unison. A stop 68, which is adapted to contact block 60 and prevent counterclockwise motion of the levers beyond a predetermined point, is supported by means of a U-shaped bracket 70 which is secured to the webs 4, 6 of the (frame. An additional stop 72 is provided to prevent clockwise motion of the levers beyond a predetermined point and this stop is engaged by an adjustable screw 73 which extends through block 69. Stop 72 in turn is supported on a cross bar 74 which is secured to the support block 24.

As best shown in FIGURE 7, the bending arms extend parallel to the sides of the crimping die and are inwardly directed at 80. These arms normally extend beyond the crimping die and have lower parallel extensions 81 inwardly curved at their tips :as shown at 32 and having heels 3.3 to limit their movement towards each other. In use, these arms are required to move relatively towards each other during counterclockwise motion of the bell crank in order to :bend the sidewalls of the terminal inwardly. To this end the levers themselves have a resilient bias inwardly towards the bell crank but are held in the positions shown in FIGURE 7 by virtue of screws 78 in the levers which bear against the opposite sides of the crimping die. Recesses 76, which function as camming surfaces, are provided on the sides of the crimping Edie which are opposed to the levers. As the bell crank rotates, block 60 contacts stop 68 and further movement of the levers and bending arms towards the anvil is prevented. Thereafter, the bell crank continues to move in a counterclockwise direction as viewed in FIGURE 4 and the crimping die moves downwardly towards the interval relative to the levers. During this dwell of the levers, the screws 78 move into recesses 76 as shown in FIGURES 7 and 8, and the ends 81 of the bending arms also move inwardly towards each other to bend the sidewalls of the terminal towards each other. Upon further movement of the crimping die, the bending arms are cammed apart by the cam surfaces 76 of the crimping die so that crimping die can be pressed against the terminal to complete the crimp. It will be understood that the levers 58 should be clamped by the spring washers 63 against the flat surfaces 62 on the bell crank with sufii cient force to ensure the movement of the levers and the bell crank as a unit during the initial stages of the stroke, however, the clamping pressure should not be unduly high in order to permit the relative motion, shown in FIGURES 7-10, between the levers and the bell crank.

Referring now to FIGURES 1, 11 and 12, the feed mechanism for feeding the terminal strip comprises a feed finger 90 which is adapted to push the strip from a source (not specifically shown) along a channel 84 on the upper edge of the front plate 54 of the machine frame. This finger is pivoted at 92 to one arm 96 of a bell crank lever and has a torsion spring 94 fitted into a slot in its base which normally biases the finger in a clockwise direction as viewed in FIGURE 11. The bell crank to which the finger is attached is pivotally mounted at 98 on a pin which in turn is mounted in front of plate 54. The other arm 1% of the bell crank is normally biased downwardly in FIGURE 11 by means of a coil spring 102 secured at its end to the base of the machine fname. The apex of the bell crank provides a flat face to which is secured a leaf spring 104, the end of which is engaged by a cm 166 mounted rotatably on a pin 133 extending from the base 2 of the frame. As shown in FIGURE 12, upon clockwise movement of this cam 1%, the end of the leaf spring 194 will be moved leftwardly in FIGURE 11 resulting in clock-wise motion of the bell crank 0n pivotal axis 98. This motion imparts a rightward movement to feed finger to feed the strip of terminals rightwardly towards the crimping anvil. Cam M96 is actuated by means of a bar secured to an extension 112 on the previously mentioned bar 33. It will thus be apparent that upon motion of the piston rod towards the front of the apparatus and leftwardly in FIGURE 4, the cam 106 will be rotated in a clockwise direction and this will cause clockwise movement of the bell crank and rightward movement of the feed finger. On the return stroke of the piston rod 34, spring 102 is effective to cause counterclockwise motion of the bell crank and retract the feed finger so that it will be positioned behind the next adjacent terminal on the strip to feed this next terminal to the crimping anvil at the end of the forward stroke.

The length of the stroke of the feed finger can be adjusted by means of stop screws 113 threaded through the opposite sides of channel 114. As shown best in FIG- URE 11A, bell crank arm 96 comes to rest against these stops at the limits of its stroke in both directions. It should be added that the leaf spring 104 on the bell crank renders it unnecessary to adjust the position of cam 106 when the stroke is changed. If this cam overtravels (continues to rotate after the edge of the bell crank arm comes to rest against the righthand stop 113 in FIGURE 11A), the leaf spring will merely be resiliently stressed to a slight extent.

It is desirable to provide some type of hold down device for lightly pressing the strip of terminals into the channel shaped feed path on the upper face of the front plate 54. To this end, there is provided an L-shaped bracket secured to channel 114 and having a leaf spring 122 on its end which extends downwardly toward the terminal feed path and parallel to the path as shown in FIGURE 11.

A shear, for shearing the strip of plastic material 86 V at a point adjacent the crimping anvil, is provided in the form of a shear blade 124 having an opening in its end through which the strip is adapted to pass. This shear blade extends through a slot in the front plate and is mounted on a slide member 126 which is held against a bracket 128 on the front plate of the frame, the face of the front plate being recessed for the accommodation of this slide. The slide is reciprocated by means of a lever 130 (FIGURE 14) which in turn is secured to a rod 134 extending parallel to, and in back of, the front plate. Rod 134 has a clamping block 136 on its end which is slotted at 138 for the reception of the flattened end 140 of a control rod 142 to which it is pivotally connected. Control rod 142 is slidably supported in bearing blocks 144 on the outside surface of web 4 to permit motion'parallel to the motion of the piston rod 34. Rod 142 is retracted during the last portion of the rightward stroke of the piston rod as viewed in FIGURE 4 by means of an arm or extension 145 on plate 38-. This plate engages a collar 147 secured to the rod 142 and pushes it rightwardly, during the final stages of the stroke, against the compression of a spring 149 interposed between the one bearing block 144 and the collar 147. It will be appreciated that only a very slight amount of movement of this rod is needed to actuate the shear 124.

Advantageously, means are provided to trim the portion of the wire which extends beyond the terminal after it has been crimped. In the preferred embodiment such means is provided in the form of a wire shear 152 which extends through a slot in the front plate and is disposed within the recess in the front plate. This wire shear is secured at its end to a hub 152 pivotally mounted on a pin 153 and has an arm 154- extending downwardly therefrom and leftwardly as viewed in 13. This arm is slotted at its end for the accommodation of a cam follower 156 which is adapted to be engaged by a cam 15% on blade holder 126. A leaf spring 16% mounted on support 129 normally biases -arm 154 in a clockwise direction as viewed in FIGURE 13 but permits counterclockwise motion of the arm. Thus, upon downward motion of the blade holder 126, hub 152 is rotated in a counterclockwise direction against the force of spring 160 and the shearing edge of the blade 152 passes relatively downwardly into the slot through which it extends and severs the end of the wire.

Extremely fine wires on which the instant machine is adapted to operate are frequently coated with a varnish type insulation which must be removed in the vicinity of the crimp, and these wires are difficult to position within the terminal, particularly if the terminal is relatively small as in the instant circumstances. In order to both strip and position the wire, there is provided a pair of stripping

wheels

162, 164 in front of the bell crank and directly behind the anvil portion of the channel 84. These stripping wheels are mounted on the ends of

shafts

166, 168 which are rotatably supported in

blocks

170, 172. Block 170 is pivoted at its rearward end to block 172 and the two blocks are held apart as shown in FIGURE 1 by the wheels themselves. Thus as the wheels progressively wear down in use, the block 17% moves downwardly relative to the block 172 to maintain the spacing between the wheels. It should be added at this point that the purpose of providing a hinged mounting for the upper plate 8 is to permit adjustment of this plate so that the wheels will be positioned with their line [of tangency in the plane of the crimping anvil. A pulley 176 on the end of shaft 168 is connected by means of a belt 178 to the pulley 18% on the end of a shaft extending from a motor 182 so that these wheels are continuously rotated during use. It will be apparent that the upper one of the wheels is turned only by virtue of its frictional contact with the lower wheel although if desired, a direct drive for both of these stripping wheels can be provided.

The stripping wheels 162, 164- may be of any desired type suitable for the wire being used. One type of stripping wheel which is particularly adapted for extremely fine wire is composed of a plurality of fibre glass discs, each disc being made up of a plurality of radially extending strands. Stripping wheels of this type will remove all of the varnish type insulation on an extremely fine wire without damaging the wire itself.

In use, the operator will generally wish to strip the end of an extremely fine wire and crimp this fine wire along with a relatively larger diameter lead wire in a terminal. To accomplish this, the operator first inserts the end of the fine wire over the anvil portion of the front plate until its end is engaged by the stripping wheels. These wheels tend to draw the wire inwardly of the machine and in doing so will remove the varnish type insulation. It is necessary for the operator to feed a length of fine wire sufficient to extend from the line of tangency of the wheels to the terminal positioned on the anvil. After this length of wire has been drawn between the wheels, the operator withdraws the fine wire by pulling on it until a stripped portion is positioned over the uncrimped terminal on the anvil. It is an advantage that during the entire operation this extremely fine wire is held taut by the wheels thereby facilitating the operation of positioning it relatively over the uncrimped terminal. After the wire has been stripped and positioned over the terminal in this manner, the second wire, usually a larger diameter lead wire, is positioned 6. within the terminal and the operator actuates the pneumatic piston cylinder. Thereafter, the piston rod moves rightwardly as viewed in FIGURE 4 and the bell crank is rotated in a counterclockwise direction. The bending arms move downwardly and then inwardly as the sequence of operation shown in FIGURES 7-9 is followed and the upstanding sidewalls of the terminal are bent partially inwardly towards each other. After this inward bending of the sidewalls, the arms move outwardly again and the crimping die presses the terminal against the anvil to firmly set these sidewalls and secure the terminal onto the wire end. After the terminal has been crimped, and the end of the bell crank has come to rest against stop 46, the piston rod 34 continues to move rightwardly and is permitted to .do so by virtue of the

resilient coupling

42, 4%) between the arm of the bell crank and the piston rod. During this final portion of the rightward stroke, the rod 142 is moved rightwardly thereby to actuate the Wire shear and the strip shear. During this period the wire will be held by the abrasive wheels so that it can be sheared in a precise location relative to the strip. After the piston rod 34 reaches the end of its rightward stroke it immediately returns and causes the bell crank to rotate in a clockwise direction thus raising the crimping and the bending arms. During this reverse stroke, the stop 72 is effective to prevent movement of the

levers

61, 58 beyond a predetermined position and the crimping die moves relatively upwardly with respect to the pin 76 (FIGURE 7). As a result the bending arms and the crimping die at the end of the stroke are positioned in a relative position shown in FIGURE 7. During the final portion of the forward stroke of the ram, cam- 106 (FIGURE 12) is rotated as described above to feed the next adjacent terminal up to the crimping anvil area of the front plate.

The salient overall advantage of the invention is that it is particularly adapted to crimp extremely small connectors onto the ends of extremely fine wires which can not be handled by the heretofore known types of crimping devices. Several features of the invention contribute to the ability of this preferred embodiment to handle such wires. As mentioned above, the abrasive Wheels hold the wire so that it can be precisely positioned relative to the terminal, an operation which would otherwise be extremely difiicult because of the delicacy of the wires and the small size of the uncrimped connectors. The preferred embodiment is also adapated to feed and to shear terminals of the particular type shown in FIGURE 2 which are extremely small and are secured to a plastic strip. The shearing means operates while the terminal is clamped securely by the crimping die and the crimping ram on the end of the bell crank provides means to bend the sides of the terminal inwardly as well as to crimp the sides after they have been partially bent together. It will be appreciated that the extremely small terminals required for fine wires can not be bent inwardly and downwardly by a single die as is common practice with terminals for larger sized wires.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only. The actual scope of the invention is intended to he defined in the following claims when viewed in their proper perspective against the prior art.

I claim:

1. Apparatus for crimping open-U type electrical terminals in strip form onto wires, said apparatus comprising. an anvil, means for feeding a succession of terminals in strip form to said anvil, a bell crank pivotally mounted at its apex, at crimping die on one arm of said bell crank whereby upon rotary motion of said bell crank said crimping die is moved relatively towards and away from said anvil, a strip shearing blade disposed adjacent said anvil and movable in a plane extending transversely of the plane of said strip and past said strip at a location between the leading terminal of said strip on said anvil and the next adjacent terminal to sever said leading terminal from said strip, actuating linkage for said blade, a reciprocable rod, lost motion means for engaging said rod with said actuating linkage during the terminal portion of the stroke of said rod in one direction, a resilient connection between said rod and the other arm of said bell crank, and a stop for said bell crank arm to prevent movement thereof after crimping of saidterminal whereby, upon movement of said rod in said one direction said bell crank is first rotated to crimp said terminal, and said strip shearing blade is then actuated while said crimping die dwells to sever said strip.

2. Apparatus for crimping open-U type terminals in strip form comprising, a bell crank pivotally mounted at its apex, a crimping die mounted on one arm of said bell crank, a fixed crimping anvil or cooperation with said crimping die, means for feeding a succession of terminals in strip form to said anvil, a shear disposed adjacent said anvil for shearing the leading terminal from said strip, a reciprocable rod, said rod being resiliently coupled to the other arm of said bell crank whereby upon movement of said rod in a first direction, said bell crank is rotated and said crimping die is moved relatively towards said anvil, a stop for said bell crank to prevent movement of said crimping die beyond a predetermined position relative to said anvil while permitting continued movement of said rod in said first direction after said bell crank has come to rest against said stop, and means acting between said terminal feeding means and said rod for actuating said terminal feed means during return movement of said rod in a direction opposite to said first direction.

3. Apparatus for crimping open-U type terminals in strip form comprising a bell crank pivotally mounted at its apex, a crimping die mounted on one arm of said bell crank, a fixed crimping anvil for cooperation with said crimping die, means for feeding a succession of terminals in strip form to said anvil, a strip shear disposed adjacent said anvil for shearing the leading terminal from said strip, a Wire shear disposed adjacent said anvil for shearing excess wire extending from said terminal, a reciprocable rod, said rod being resiliently coupled to the other arm of said bell crank whereby upon movement of said rod in a first direction, said bell crank is rotated and said crimping die is moved relatively towards said anvil, a stop for said bell crank to prevent movement of said crimping die beyond a pre determined position relative to said anvil While permitting continued movement of said rod in said first direction, means acting between said rod and both of said shears 'for actuating said shears during movement of said rod in a first direction after said bell crank has come to rest against said stop, and means acting between said terminal feed means and said rod for actuating said terminal feed means during return movement of said rod in a direction opposite to said first direction.

4. Crimping apparatus for crimping open-U type connectors comprising, a fixed anvil, a crimping die movable relatively towards and away from said anvil, a pair of bending arms disposed on opposite sides of said crimping die and having tip portions normally extending beyond said die towards said anvil, portions of said arms being held frictionally against the sides of said crimping die whereby said arms are normally movable with said die but said die is movable relative to said arms when said arms are held against movement, said arms being resiliently biased inwardly towards said die, stop means for preventing movement of said arms during a terminal portion of the stroke of said die towards said anvil, and camming means acting between said die and said arms, said camming means functioning to permit said arms to move by virtue of their resilient tendencies, relatively inwardly and their tips to move relatively towards each other during said terminal portion of said stroke, and said camming means causing said arms subsequently to move apart whereby, during said stroke, said bending arms bend the sidewalls of said terminal inwardly, and said crimping die thereafter bends said sidewalls downwardly Ito crimp said terminal onto a wire.

5. Crimping apparatus for crimping open-U type connectors comprising, a fixed anvil, 'a crimping die movable relatively towards and away from said anvil, a pair of bending arms carried by, and disposed on opposite sides of, said crimping die, said die being movable relative to said arms upon application of a holding force to said arms, said arms normally extending beyond said crimping die and being resiliently biased inwardly towards said die, means for applying a :holding force to said arms during a terminal portion of the stroke of said die towards said anvil, and cam means for permitting said arms to move inwardly towards each other and for subsequently moving said arms apart during said terminal portion of said stroke whereby said bending arms inwardly bend the sidewalls of a terminal positioned on said anvil and said die thereafter bends said arms downwardly over the base of said terminal.

References Cited in the file of this patent UNITED STATES PATENTS

Claims

4. CRIMPING APPARATUS FOR CRIMPING OPEN-U TYPE CONNECTORS COMPRISING, A FIXED ANVIL, A CRIMPING DIE MOVABLE RELATIVELY TOWARDS AND AWAY FROM SAID ANVIL, A PAIR OF BENDING ARMS DISPOSED ON OPPOSITE SIDES OF SAID CRIMPING DIE AND HAVING TIP PORTIONS NORMALLY EXTENDING BEYOND SAID DIE TOWARDS SAID ANVIL, PORTIONS OF SAID ARMS BEING HELD FRICTIONALLY AGAINST THE SIDES OF SAID CRIMPING DIE WHEREBY SAID ARMS ARE NORMALLY MOVABLE WITH SAID DIE BUT SAID DIE IS MOVABLE RELATIVE TO SAID ARMS WHEN SAID ARMS ARE HELD AGAINST MOVEMENT, SAID ARMS BEING RESILIENTLY BIASED INWARDLY TOWARDS SAID DIE, STOP MEANS FOR PREVENTING MOVEMENT OF SAID ARMS DURING A TERMINAL PORTION OF THE STROKE OF SAID DIE TOWARDS SAID ANVIL, AND CAMMING MEANS ACTING BETWEEN SAID DIE AND SAID ARMS, SAID CAMMING MEANS FUNCTIONING TO PERMIT SAID ARMS TO MOVE BY VIRTUE OF THEIR RESILIENT TENDENCIES, RELATIVELY INWARDLY AND THEIR TIPS TO MOVE RELATIVELY TOWARDS EACH OTHER DURING SAID TERMINAL PORTION OF SAID STROKE, AND SAID CAMMING MEANS CAUSING SAID ARMS SUBSEQUENTLY TO MOVE APART WHEREBY, DURING SAID STROKE, SAID BENDING ARMS BEND THE SIDEWALLS OF SAID TERMINALS INWARDLY, AND SAID CRIMPING DIE THEREAFTER BENDS SAID SIDEWALLS DOWNWARDLY TO CRIMP SAID TERMINAL ONTO A WIRE.