US3247571A - Crimping machine - Google Patents

Description

April 26, 1966 c. R. MENTZERY 3,24

ORIMPING MACHINE Original Filed Jan. 27. 1960 4 Sheets-Sheet 1 A ril 26, 1966 c. R. MENTZER CRIMPING MACHINE 4 Sheets-Sheet 2 Original Filed Jan. 27, 1960 April 26, 1966 c. R. MENTZER 3,

' CRIMPING MACHINE Original Filed Jar x. 27. 1960 4 Sheets-Sheet 5 April 26, 1966 c, R, MENTzER 3,247,511

CRIMPING MACHINE Original Filed Jan. 27, 1960 4 Sheets-Sheet .4

United States Patent 3,247,571 CRIMPIYG MACHINE Charles R. Mentzer, Harrisburg, Pa., assignor to AlHP Incorporated, Harrisburg, Pa.

Original application Jan. 27, 1960, Ser. No. 5,044, now Patent No. 3,091,275, dated May 28, 1963. Divided and this application May 14, 1963, Ser. No. 280,272

2 Claims. (Cl. 29--33) This application is a division of my co-pending application Serial Number 5,044, filed January 27, 1960, for Crimping Machine, now Patent Number 3,091,275.

This invention relates to apparatus for stripping varnish type insulation from the ends of wires and crimping connectors onto the stripped ends.

Varnish type insulations for wires such as Formvar insulation (polyvinyl formal resins) and Kel-F insulation (trifiuorochloroethylene) are frequently used for coil windings, motor leads, etc. where a relatively thin and high dielectric strength insulation is required. Wires associated with components of this type are often relatively fine, e.g., in the range of AWG 24-44. These varnish type insulations do not respond to conventional insulation stripping operations but are commonly removed chemically by the action of a suitable solvent. The necessity for chemical stripping in the past has precluded the provision of a stripping means on crimping machines for varnish-insulated wires.

In the particular instance where a relatively fine wire is being crimped onto a connector, an additional problem arises because of the fineness of the Wire and the difiiculty of accurately positioning it with respect to the connector. For example, an AWG 40 wire has a diameter of 3 mils and a connector which would be adapted to receive such a wire would be correspondingly small. It is thus difficult for the operator forming a crimped connection between such a Wire and connector to position the wire accurately with respect to the connector during the crimping operation. The difficulty of positioning such fine wires in a crimping apparatus is complicated if the wire end is slightly curved as is frequently the case with a wire recently removed from a coil.

An object of the present invention is to provide an improved apparatus for stripping varnish type insulation from the ends of wires and crimping a connector onto the stripped end. A further object is to provide a stripping and crimping apparatus for wires having varnish type insulation and including means for assisting in locating the wire relative to the connector to which it is being crimped. A further object is to provide a stripping and crimping apparatus having means for trimming the projecting end of the wire after the connector has been crimped to the wire.

These and other objects of the invention are achieved in a preferred embodiment thereof comprising an anvil for supporting a terminal and a crimping die which is movable towards and away from the anvil, to crimp a connector onto a wire. A pair of abrasive stripping drums are mounted adjacent to the anvil on parallel spaced apart axes. These drums are in tangential contact with each other so that the wire can be positioned with its axis extending between the die and anvil and between the line of contact of the stripping drums. The drums will then tend to pull the wire inwardly and will abrasively remove the varnish type insulation. Since the wheels pull the Wire and place it under a slight tension during the stripping "ice alignment with the terminal so that during a subsequent crimping operation, the terminal will be crimped onto this stripped portion. The preferred embodiment of the invention also has a trimming blade disposed between the stripping drums and the anvil which can be actuated after the crimping operation has been completed thereby to trim the projecting portion of the wire which extends towards the abrasive drums.

In the drawing:

FIGURE 1 is a perspective view of one form of crimp ing apparatus containing the insulation stripping and trimming features of the present invention.

FIGURE 2 is a sectional side view showing the forward portion of the apparatus of FIGURE 1.

FIGURE 3 is a fragmentary view on an enlarged scale showing the insulation stripping drums and their relationship to the crimping anvil and the trimming blade.

FIGURE 4 is a view taken along the lines 44 of FIGURE 3 and showing a Wire gripped between the stripping drums.

FIGURE 5 is a view similar to FIGURE 4 but showing the position of the wire after it has been partially withdrawn from the stripping drums.

FIGURE 6 is a fragmentary perspective view showing the wire trimming blade and the terminal strip severing blade.

FIGURE 7 is a fragmentary perspective view illustrating the manner in which the connector strip severing blade is actuated.

FIGURE 8 is a perspective view of a short section of plastic strip having connectors mounted on its surface.

The invention is herein'disclosed in conjunction with a crimping apparatus which is fully described in the aboveidentified Patent Number 3,091,275. The structure and operation of the apparatus as regards the crimping die and anvil, and the strip feeding means will be described below only to the extent necessary for an understanding of the present invention.

The disclosed embodiment comprises a frame having a base plate 2, and a cover plate 6 with spaced apart vertical support members 4 extending between the two plates. A front panel 8 mounted on the forward end of the apparatus has an upper surface 10 over which the strip S is fed. Advantageously, flanges 12 are provided on each side of surface 10 to guide the strip along its feed path. Feeding of the strip is accomplished by means of a reciprocable feed finger 14, the actuation of which is described in the above-identified Patent Number 3,091,275. A spring 16 is provided in spaced relationship from surface 10 to hold the strip against the feed surface and to prevent retractile movement during retraction of the feed finger.

An anvil surface 18 is provided on the upper surface 10 of panel 8 which is opposed to a crimping die 20 on the end of a depending bar 21. At its upper end this bar is secured to one arm 22 of a bell crank, the other arm 24 of which extends downwardly as viewed in FIG- URE 2 and between the frame members 4. This bell crank is pivotally mounted adjacent to its apex at 26 between a pair of upstanding cars 28 which extend from cover plate 6.

The lower end of arm 24 is enlarged as shown at 30 and has an oversized opening through which a rod 32 extends. The righthand end of rod 32 is, in turn, threaded to the end of a piston rod 34 of a piston cylinder 36. A nut 40 is threaded onto the lefthand end of the rod 32 and a coil spring 42 is interposed between this nut and a Washer 44 which bears against the lower end of hell crank arm 24.

The arrangement described above is such that upon rightward movement of piston rod 34 as viewed in FIG- URE 2, the bell crank is rotated in a counterclockwise direction about its pivotal axis 26 and the crimping die 20 moves into engagement with the open-U type terminal disposed on anvil surface 18. The amplitude of the stroke of the bell crank can be adjusted by means of a stop block 46 having an upstanding shoulder 48 which is engaged by the lower end of arm 24 when the desired limit of the stroke is reached. Block 46 can be moved rightwardly or leftwardly in FIGURE 2 by means of an adjusting screw 50 to vary a stroke of the bell crank.

The particular type of crimping apparatus shown includes a pair of bending arms 52 on opposite sides of the bar 21 which are adapted to initially bend the sidewalls of the connector inwardly and prior to final crimping which takes place when the die 20 bottoms against the connector. The arms 52 have inwardly directed lower ends 54 for engagement with the connector sidewalls and are secured at their upper ends to spring plates 60 which extend rearwardly as viewed in FIGURE 1 on each side of the bell crank. The plates 60 have a resilient tendency to move relatively towards the sides of the bell crank and are maintained in the positions of FIG- URE 1 by pins 56 which extend through the plates 68 and bear against the sides of the bar 20. Intermediate their ends these plates 60 are clamped against the sides of the bell crank by means of a pin 64 which extends through circular openings in the plates and through an arcuate slot 66 inthe bell crank. Spring washers 62 are interposed between the heads of pin 64 and the sides of the plates 60 so that relative movement of the plates and therefore the bending arms 52 with respect to the bell crank and the crimping die 20 is permitted within the limits defined by the slot 66. The plates 60 each have a depending portion 61 through which the pin 26 loosely extends. Theplates 60 extend rearwardly beyond the bell crank and have a block 68 secured to their ends so that they move with respect to the bell crank as a single unit. The upper surfaces of the block 68 is adapted to be engaged by the lower end of a screw 70 which is mounted in the cross member 72 of a U-shaped frame 73 secured as indicated at 74 to the top plate 6.

It will be apparent that upon counterclockwise motion of the bell crank the lower ends 54 of the arms 52 will first reach the vicinity of the channel-shaped connector on the anvil surface and that the upper surface of the block 68 will engage the lower end of the screw 70 thereby preventing further arcuate movement of the plates 60 and the arms 52. Thereafter the bell crank will continue to rotate and the crimping die will move relatively towards the lower ends of the arms. During such movement, a pair of grooves 58 on the sides of the bar 21 will move relatively past pins 56 and plates 60 will be permitted to move relatively towards the sides of bar 21. As a result, the lower ends of the arms 54 move towards each other and fold the sidewalls of the connector over each other as explained in US. Patent 3,091,275. As the grooves 58 move relatively past the pins 56, the plates 60 are cammed apart and the arms move out of engagement with the connector so that the crimping die 20 can move against the folded over sidewalls of the connector and finish the crimping operation.

When the bell crank returns to its initial position (FIGURE 1) the plates 60 are also returned to their initial position relative to the bell crank by means of a stop 69 which is engaged by a depending screw 67 in the block 68. In other words, when the bell crank swings in a clockwise direction as viewed in FIGURE 2, the lower end of the screw first engages the stop 69 and the block 68 and arms 60 are prevented from further rotary movement. Thereafter, the bell crank continues to rotate and the grooves 58 move relatively past the pins 56 until the crimping die is above the ends of 54 of the arms 52 as shown in FIGURE 1.

Referring particularly to FIGURES 3-5, a pair of abrasive insulation stripping drums 76, 78 are mounted on parallel spaced apart axes adjacent to the upper surface 10 of the panel 8, the position of these drums being such that their line of tangency is on the same level as, or slightly below, the level of the surface of anvil 18. Stripping drums 76, 78 are advantageously composed of an abrasive and resilient material so that the varnish type insulation will be grounded from the surface of the wire without grinding of the wire itself. A preferred form of stripping drum comprises a plurality of Fiberglas disks mounted on the shafts 80, 82 in side-by-side relationship. Each disk is composed of a multiplicity of laterally extending Fiberglas strands so that the varnish type insulation is softened by the heat generated by the rolls and is then brushed from the surface of the wire.

The shaft on which the upper drum 76 is mounted extends rotatably through a bearing in a plate 86 which is mounted at 88 on a bracket extending from cover plate 6. The shaft 82 on which the drum 78 is mounted extends through a bearing on a fixed plate 9! on the upper surface of plate 6. The stripping drums are driven by means of a belt 98 which extends over pulleys 94, 96 on the ends of the shafts 88, 82 and over an idler pulley 104 on a block 106 which, in turn, is mounted on plate 86. The belt 98 is continuously driven by a pulley 108 on the output shaft on a motor 102 mounted on the upper surface of the plate 6.

As shown in FIGURE 8, the connectors are mounted in spaced apart relationship on a strip of plastic tape which is fed by the feed finger 14. The tape is fed through an opening in a strip cutting blade .108 which extends through a slot in the surface 10 of the panel 8. On its lower end, the blade 188 is secured to a plate 110 which bears against a triangular plate 112 on panel 8. Intermediate its ends, the plate 110 has a notch which receives the rounded end of a lever 114. The opposite end of lever 114 is secured to an oscillatory shaft 116 which extends parallel to the panel 8 and through the frame member 4. On its end, the shaft 116 is provided with a clevis 118 in which the end of a rod 120 is pivoted. This rod extends rearwardly through bearing blocks 119, 122 on the external surface of the frame member 4. A collar 126 is mounted on the rod 120 intermediate its ends and a coil spring 124 surrounds the rod and bears against the block 122 and the collar 126 normally to bias this rod leftwardly as viewed in FIGURE 1.

Since the pivotal connection between the end of the rod 120 and the clevis 118 is below the axis of oscillatory shaft 116, it is apparent that rightward movement of the rod 120 from the position of FIGURE 7 will cause the shaft 116 to be rotated in a counterclockwise direction as viewed in FIGURE 7 thereby to cause the lever 114 to pull the severing blade 108 downwardly. Such rightward movement of the rod 120 is brought about during the final portion of the crimping operation by means of an extension 128 on a bar 130 which is mounted on the rod 32. The extension 128 projects through an opening in frame member 4 and is adapted to engage the collar 126 as it moves rightwardly from the position shown in FIGURE 1.

The disclosed embodiment also provides a wire trimming blade 132 which is movable across the axis of a wire extending towards and into the drums 76, 78. This blade 132 is provided on the end of a bar 134 which extends through a slot on the surface 10 and beside the bar 119. At its lower end the plate 132 is secured to a block 136 having an arm 137 which projects towards the side of the bar 110. Block 136 is pivoted at its upper end 137 so that upon counterclockwise rotation of this block about its pivotal axis the blade 132 will move relatively into its slot on the surface 10 to sever a wire. Such movement of the block 136 is brought about by a camming block 140 on the side of the bar 110 which engages a cam roller 138 on the end of arm 137 of the block 136. A leaf spring 142 is secured to the righthand triangular plate 113 and bears against the block 136 to normally bias it to the position shown in the drawing.

In use, the parts will normally be in the position shown in FIGURES 1 and 2 and the motor 102 will be running continuously so that the drums 76, 78 will be rotating continuously. An uncrirnped connector will be positioned on the anvil surface 118 from the previous operating cycle as explained in the above identified Fatent Number 3,091,275. The operator first inserts the wire from the left in FIGURE 2 until its end is between the two plates 86, 90. He then moves the wire leftwardly until it passes between the drums 76, 78 at which time the wire will be pulled taut between the operators fingers and the drums. The wire is then moved further leftwardly in FIGURE 1 while it is held between the continuously rotating drums until it is in alignment with the uncrimped connector at which time the operator withdraws a portion of the wire from between the drums so that a stripped section of wire is disposed above and in alignment with the uncrimped connector (FIGURES and 5). As shown in FIGURE 5, the drums continue to clamp the wire and hold its righthand end portion when it is finally positioned with respect to the terminal for the crimping operation. This holding of the righthand end of the wire and the tension imparted to the wire between the drums and the operators fingers assists in positioning or locating the wire accurately over the uncrimped connector. After the wire has been positioned as shown in FIGURE 5, a suitable switch, usually a foot switch, is actuated to admit air into the lefthand end of the piston cylinder 36 thereby to cause piston rod 34 to move rightwardly as viewed in FIGURE 2. Such movement of the piston rod causes the bell crank to rotate about its pivotal axis and moves the bend-ing arms and the crimping die into engagement with the connector as described above. At the end of the crimping operation, the extension 128 of the 'bar 130 engages the collar 126 of the rod 120 to cause oscillation of the shaft 116 and downward movement of'the strip cutting blade 108. At the same time the severing knife 132 moves relatively downwardly and severs the projecting end of the wire which extends beyond the crimped connection.

Changes in construction will occur to those skflled in the art and various apparently diiferent 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 be defined in the following claims when viewed in their proper perspective against the prior art.

I claim:

1. Apparatus for stripping the end of an electrical conductor and applying a terminal to said end comprising, an anvil for supporting said terminal, said anvil having a front side and a back side, a crimping die movable towards and away from said anvil to crimp said terminal onto a wire disposed between said die and anvil, a pair of abrasive insulation stripping drums in tangential contact with each other, said drums being rotatable on parallel axes extending beside said back side of said anvil, and severing means disposed between said drums and said anvil, said severing means being movable transversely of the axis of said wire whereby, upon manual insertion of an insulated wire from said front side of said anvil between said die and anvil and feeding said wire between said drums, said wire is stripped, and upon manual retraction of said wire, and positioning a stripped portion of said Wire between said anvil and said die and in alignment with a terminal on said anvil, said terminal is crimped onto said wire by said die, and upon actuation of said severing means, the portion of said Wire extending from said anvil to said drums is trimmed.

2. Apparatus for stripping a varnish-type insulation coating from the end of an electrical conductor and crimping a connector onto the stripped end comprising, a pair of abrasive insulation stripping drums rotatable on parallel spaced-apart axes, said drums being in tan= gential contact with each other, a crimping anvil having a connector supporting surface and having a front side and a back side, said axes extending beside said back side of said anvil with the line of tangency of said drums lying substantially in the plane of said connector supporting surface, a conductor cutting blade between said drums and said surface and movable transversely of said line of tangency, a crimping die movable relatively towards and away from said surface, means for feeding a strip of terminals towards said crimping anvil to position the leading terminal of said strip on said surface of said anvil, strip severing means adjacent to said anvil and upstream, relative to the direction of strip feed, from said anvil for severing said leading connector from said strip, and actuating means for sequentially moving said die towards said anvil, moving said cutting blade transversely of said line of tangency, and actuating said severing means whereby, a conductor manually h ld on said front side of said anvil and having its end gripped between said abrasive drurns can be manually located in alignment with said leading connector and pulled towards said front side of said anvil to locate a stripped portion of said conductor in alignment with said leading connector, and said leading connector is crimped onto said stripped portion upon movement of said die towards said surface of said anvil, and the portion of said conductor extending from said anvil to said drums is trimmed by said cutting blade, and said leading connector is severed from said strip by said strip severing means.

References Cited by the Examiner UNITED STATES PATENTS 1,523,529 1/1925 Hultman 29-335 2,170,672 8/1939 Anderson 819.51 X 2,225,200 12/1940 Ames 81-9.51 X 2,873,511 2/1959 Folkenroth 29- 33.10 2,929,083 3/1960 Davis 81-9.51 X 3,115,695 12/1963 Schwalm 2933.10

RICHARD H. EANES, JR., Primary Examiner.

Claims (1)

1. APPARATUS FOR STRIPPING THE END OF AN ELECTRICAL CONDUCTOR AND APPLYING A TERMINAL TO SAID END COMPRISING, AN ANVIL FOR SUPPORTING SAID TERMINAL, SAID ANVIL HAVING A FRONT SIDE AND A BACK SIDE, A CRIMPING DIE MOVABLE TOWARDS AND AWAY FROM SAID ANVIL TO CRIMP AND TERMINAL ONTO A WIRE DISPOSED BETWEEN SAID DIE AND ANVIL, A PAIR OF ABRASIVE INSULATION STRIPPING DRUMS IN TANGENTIAL CONTACT WITH EACH OTHER, SAID DRUMS BEING ROTATABLE ON PARALLEL AXES EXTENDING BESIDE SAID BACK SIDE OF SAID ANVIL, AND SEVERING MEANS DISPOSED BETWEEN SAID DRUMS AND SAID ANVIL, SAID SEVERING MEANS BEING MOVABLE TRANSVERSELY OF THE AXIS OF SAID WIRE WHEREBY, UPON MANUAL INSERTION OF AN INSULATED WIRE FROM SAID FRONT SIDE OF SAID ANVIL BETWEEN SAID DIE AND ANVIL AND FEEDING SAID WIRE BETWEEN SAID DRUMS, SAID WIRE IS STRIPPED, AND UPON MANUAL RETRACTION OF SAID WIRE, AND POSITIONING A STRIPPED PORTION OF SAID WIRE BETWEEN SAID ANVIL AND SAID DIE AND IN ALIGNMENT WITH A TERMINAL ON SAID ANVIL, SAID TERMINAL IS CRIMPED ONTO SAID WIRE BY SAID DIE, AND UPON ACTUATION OF SAID SEVERING MEANS, THE PORTION OF SAID WIRE EXTENDING FROM SAID ANVIL TO SAID DRUMS IS TRIMMED.

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