Hand held compressed air powered insulated wire stripper

Abstract: A hand held insulated wire stripper uses compressed air power, instantaneously, to grip an insulated wire and to cut the insulation thereof. Thereafter, the insulation is stripped from the wire and ejected. The forces created by the compressed air power originate horizontally and then via cam surfaces and levers are redirected vertically to close gripper and cutter subassemblies. Upon release of the compressed air power, the forces of springs return the components to their starting positions. An insulated wire is inserted, then the compressed air power is turned on, and while it is on, the gripping, cutting, stripping, ejecting, and withdrawal of the stripped wire is all undertaken.

Description: This invention relates to a hand held compressed air powered insulated wire stripper. By 'hand held' there is meant, in this specification, apparatus intended to be hand held; this phrase does not necessarily mean that the apparatus is actually being held in a hand. Although several models of insulated wire stripping machines are available, which rest on a bench or on their own support, to receive ends of an insulated wire thereafter subsequently and automatically to strip the insulation off a wire conductor to expose a specified length of wire end, there is possibly only one model of a hand held insulated wire stripper, which automatically strips the insulation off a wire conductor. The insulated wire stripper referred to as a pneumatic wire stripper, requires the concurrent operator's actions of releasing the lever of a compressed air valve, while simultaneously and gently withdrawing the insulated wire, now with the end thereof stripped, from within this pneumatic wire stripper. These necessary concurrent actions, on the part of the operator, prevent the so called mushrooming of the strands of a stripped end conductor. Most of the hand held insulated wire strippers require the operator to squeeze together his or her fingers to close a plier action type insulated wire stripper. This is a tiresome daily activity, therefore there is a need for a compact hand held insulated wire stripper to be used more extensively, which will be used without requiring any stressful finger squeezing operations. Instead, the operator's fingers and hand will only be used to support the insulated wire stripper, and to move a control of an automatically operating insulated wire stripper to initiate and to continue a wire stripping function. Patent Specification CH-A-336470 discloses a pneumatic wire stripper wherein in operation air is introduced between two pistons to cause a first piston to slide on a piston rod and, by means of cams, cause gripping of an inserted wire to be stripped; the other piston then moves away from the first piston to cause stripping cutters coupled to the piston rod to be cammed inwardly to cut the insulation and then move along rails to strip the insulation from the wire. Upon removal of the applied air pressure the components all return under spring power to their original positions so as to be ready to effect a further gripping, cutting and stripping operation. According to the invention there is provided a hand held compressed air powered insulated wire stripper, comprising: a hollow outer housing; a hollow inner housing which slides inside the hollow outer housing; an open top inner slide for sliding movement within the hollow inner housing; a cutter actuator lever pivotally positioned on the open top inner slide; an insulation cutter subassembly mounted on both the open top inner slide and the cutter actuator lever for cutting action upon movement of the cutter actuator lever; an insulated wire gripping subassembly mounted on the hollow inner housing to grip an end of an insulated wire during the cutting of the insulation thereof; a back plate secured to the hollow outer housing and to be secured to a cylinder of a compressed air actuator; an extended portion of a piston secured to a piston of the compressed air actuator and positioned and guided by the back plate; a two piece flexible coupler assembly interconnecting the extended portion of the piston and the cutter actuator lever at the rear portion thereof, to move the insulation cutter subassembly via the action of the lever arm, to cut the insulation off an end of an insulated wire, upon the initiation of a retracting movement of the extended portion of the piston, and upon the continued retracting movement of the extended portion of the piston, thereafter retractably to move both the cutter actuator lever, while remaining in the position to keep the cutter subassembly in the cutting position, and the open top inner slide, as a subassembly, relative to the hollow inner housing thereby to strip the cut insulation off an end of the originally insulated wire end, while the insulated wire gripping subassembly mounted on the hollow inner housing continues to grip the inserted end of the insulated wire; a positioning cam subassembly extending from the back plate subassembly to the insulated wire gripping subassembly on the hollow inner housing, to actuate the insulated wire gripping subassembly to grip an inserted end of insulated wire, upon the initiation of a retracting movement of the extended portion of the piston, and to continue the gripping during the entire stripping movement; and a releasible override stop subassembly to keep the open top inner slide in a commencing position within the hollow inner housing during the gripping of an insulated wire end and the cutting of the insulation of the insulated wire end, and then to be overridden during the stripping of the insulation from the wire. Such a hand held automatically operated insulated wire stripper can be sized for convenient and comfortable holding in one hand of an operator. After his or her other hand and fingers are used to insert a length of an insulated wire through a designated wire size entry to reach an adjustable positioned stop, the operator, using a finger on the hand holding the insulated wire stripper, moves a control to cause the insulated wire stripper automatically to function to strip the insulation off the wire without damaging the wire. Even if the wire is coated, the coating will not be damaged. While the operator continues to hold the control in the position to which he or she moved it to cause the stripping action, the operator quickly pulls out the insulated wire, now having a stripped end. There is then no possibility of the end of the stripped portion of the wire being hit by spring returned parts, causing any unwanted mushrooming of a wire end. This overall insulated wire stripper includes a compressed air actuator, having an internal coiled return spring, and a compressed air control valve. The wire stripping portions also include an internal coiled return spring. At the commencement of a wire stripping operation these coiled return springs, acting together, have all of the components of this hand held compressed air powered wire stripper positioned to receive an end of an insulated wire. After an end of an insulated wire is inserted to contact a preset adjustable position stop by the operator using his or her other hand, then this hand held insulated wire stripper is ready for the commencement of the automatic stripping of the insulation from the wire end without damaging the wire, and without damaging any coating on the wire. Moving of the compressed air control valve directs compressed air into a cylinder of the compressed air actuator and against a piston therein. A previously extended portion of this piston is thereby partially withdrawn into the cylinder against the force of the coiled compression spring within the cylinder. Also another coiled compression spring surrounding this extended portion of the piston is compressed, upon this withdrawing of a partial length of this initially extending portion of this piston. The extending end of the extending portion of the piston is indirectly flexibly coupled, to an inner slide of this wire stripper via a cam surfaced portion of a coupler, and cam surfaced portions of a spring returned lever, pivotally mounted on the inner slide. The sliding of this inner slide is directionally controlled by an inner housing which surrounds the inner slide. The insulation cutter assembly, which also strips away the insulation, is mounted at the front of this inner slide. The lower cutter blade portion is non movably held in this inner slide. The upper blade portion is movably held via supporting pins to a lever which is in turn pivotally mounted to the inner slide using a pivot pin or shaft. A return spring acting between this lever and the inner slide keeps the insulation cutter assembly open. When the compressed air is initially turned on, the retracting movement of the extending piston portion, via the flexible coupling and the cam surfaced portions thereof, causes the pivoting of this lever and the movement of the upper blade downwardly to cause the controlled cutting of the insulation. Before this cutting of the insulation and during this cutting of the insulation, the insulated wire has been gripped upon the closing together of an upper gripper portion and a lower gripper portion. The opening and closing of the insulated wire gripper is directly undertaken upon the relative movement of respective sets of upper and lower cam pins. They are held in place by a cam pin block which is secured to the back plate of the insulated wire stripper. These gripper portions are positioned just inside a front cover of the inner housing, against a shoulder thereof, and this cover has respective entries for respective size wires. The lower gripper portion is held captive between the front cover, the shoulder of the inner housing and the lower cam pins. The upper gripper portion is slidably held captive between the front cover, the shoulder of the inner housing, and the upper cam pins. During the initial insulated wire gripping period and also during the initial simultaneous cutting of the insulation period, the inner slide is releasibly held captive to the inner housing. Together they move rearwardly for a short distance nearer the cam pin block and the back plate, until the gripper and the cutter are both firmly bearing respectively against the insulated wire and the wire. These firmly bearing positions of the gripper and cutter are reached before a disassembly limit structure could ever become effective. This disassembly limit structure includes a limit structure surrounding a slot in the inner housing contacts a projecting stop screw, which is positioned in the cam pins holding block adjacent the back plate of the wire stripper. The inner slide is released from the inner housing, when the compressed air pressure increases sufficiently, to overcome the initial positioning force of a leaf spring secured to the inner housing, which initially positions a portion of a transverse control pin in a transverse control pin receiving groove in the inner slide. When the leaf spring force is overcome, the control pin is moved clear of the inner slide and completely into a transverse receiving opening in the inner housing, which initially received a portion of this transverse control pin. The inner slide, when thereafter independently retracting with the extending portion of the piston, carries the forced together insulation cutter portions so they strip the cut insulation from the wire. The wire is not damaged, nor is any coating on the wire damaged during these cutting and stripping operations. When the inner slide is released, its momentum and its continuous pulling by the retracting piston ensures its full retraction. At the completion time of the retraction of the inner slide, the piston is also fully retracted in the cylinder of the compressed air actuator. Also at this time, the force holding the gripper together and the force holding the cutter together are simultaneously released. The cam of the coupler at this time is no longer transmitting a force, via the cam of the lever. Therefore, the return spring positioned in the lever, pivotally moves the lever to the horizontal starting position thereof. Via the pin interconnections, this lever movement causes the opening movement of the cutter back to the starting open position thereof. Also during this full return time, while the compressed air pressure is still being applied, there are no forces being applied by the relative positioning of the cam pins to keep the gripper closed. When the retracting air pressure is still turned on, and the gripper and the cutter are freed for opening movement or have so opened, the operator quickly pulls out the stripped end of this previously overall insulated wire, thereby eliminating any possibility of the wire end later becoming mushroomed, upon the return motions of any components of this insulated wire stripper. A downwardly pivoting, self returning, ejector is pivotally mounted on the inner slide. After the insulation is cut and stripped from the wire, this ejector is contacted by a cam screw secured to the inner housing, and caused to pivot to eject the cut insulation clear of this insulated wire stripper. An outer housing is secured to the cam pin mounting block adjacent the back plate and partially extended over the inner housing. The operator places his or her hand about this outer housing. Also the pressurized air control valve is mounted on this outer housing for convenient manipulation by the person's fingers of his or her holding hand. The person's other hand is used to insert the insulated wire and to withdraw the insulated wire, after the end thereof has had the insulation stripped clear of the wire and this insulated wire stripper. The overall compactness of this hand held compressed air powered insulated wire stripper, and its comparatively lighter weight, and its automatic functioning, ensures that this hand tool will be comfortably and efficiently used to carefully strip insulated wires. Preferably, the front plate entries, the number of the gripper opening portions, and the number of the insulation cutter opening portions, are all multiple in number and aligned parallel to one another, and each sized differently, so an operator may use this insulated wire stripper to strip the insulation off differently sized insulated wires. The insulated wire grippers and insulation cutters are conveniently removable, and other ones for different insulated wire sizes can conveniently be interchanged to meet changing insulated wire size specifications. A preferred embodiment of the hand held compressed air powered insulated wire stripper is illustrated in the accompanying drawings, wherein: Figure 1 is a perspective view of a hand held compressed air powered insulated wire stripper according to the invention, assembled and ready to receive a compressed air supply and then to receive an end of an insulated wire; Figure 2 is a perspective exploded view of most of the parts of the insulated wire stripper; Figure 3 is a partial vertical sectional view taken in a vertical longitudinal plane located nearer a side of this insulated wire stripper, showing the opened insulated wire gripper subassembly, and the cam pins, before any compressed air is admitted; Figure 4 is a partial vertical sectional view taken in the same vertical longitudinal plane, as shown in Figure 3, showing the closed insulation wire gripper subassembly, and the cam pins, after the compressed air has been admitted; Figure 5 is a partial vertical sectional view, taken in a vertical longitudinal plane located along the longitudinal centerline of this insulated wire stripper, showing the opened insulated wire gripper subassembly, and the opened insulation cutter subassembly, and also indicating this open position of the lever, which eventually moves the upper insulation cutter; before any compressed air is admitted, and the return springs are all effective in creating this starting arrangement of the gripper subassembly and the insulation cutter subassembly; Figure 6 is a partial vertical sectional view, taken in the same vertical longitudinal plane as shown in Figure 5, showing the closed gripper subassembly, and the closed insulation cutter subassembly, the latter, closed by the operation of the lever, and also showing the inner slide and the inner housing still releasibly held together, as previously shown in Figures 3, 4, and 5, and thereby also indicating the inner slide is stopped from retracting any farther within the inner housing, even though the compressed air has been admitted; Figure 7 is a partial vertical sectional view, taken in the same vertical longitudinal plane as shown in Figures 5 and 6, showing how the released inner slide has moved back within the inner housing, and the closed insulation cutter subassembly has moved to strip the cut insulation from the wire, when the build up of compressed air pressure has exceeded the holding power of a flat spring, originally keeping a transverse locking pin in place; Figure 8 is a partial vertical sectional view, taken in a vertical longitudinal plane located very near an inner side of this insulated wire stripper, showing a slide returning motion control slotted structure of the inner housing, made of aluminum, positioning a vertical steel stop rod, to make contact, as necessary, with a steel stop pin threaded into the slide, thereby avoiding any possible excessive return motion of the slide, which otherwise could dislodge the gripper subassembly; Figure 9 is a near front elevational view of the insulated wire stripper with some portions removed, to show how an end of an insulated wire has been entered into the center one of the three differently sized openings of an opened insulated wire gripper subassembly, having an upper gripper portion and a lower gripper portion before the compressed air has been turned on; Figure 10 is a near front elevational view of the insulated wire stripper, with some portions removed, similar to Figure 9, but showing, however, how the insulated wire gripper subassembly has closed to grip the inserted end of the insulated wire, which has been inserted in centerline located entry-, after the compressed air has been turned on; Figure 11 is a near front elevational view of the insulated wire stripper, with some portions removed, to show the insulation cutter subassembly in the open position, before the compressed air has been turned on; Figure 12 is a near front elevational view of the insulated wire stripper, with some portions removed, to illustrate the insulation cutter subassembly in the closed position, after the compressed air has been turned on, and for clarity, the inserted insulated wire is not shown. Figure 13 is a partial vertical sectional view taken along the longitudinal center plane of the insulated wire stripper to show the entry of the end of the insulated wire passed through the opened insulated wire gripper subassembly and beyond through the opened insulation cutter subassembly to contact the adjustable position stop, before the compressed air has been turned on; Figure 14 is a partial vertical sectional view, similar to Figure 13, taken along the longitudinal center plane of the insulated wire stripper, showing how the insulation of the inserted end of the insulated wire has been cut, upon the movement of the lever, in turn moving the upper cutter downwardly, and illustrating also how the insulation ejector, when incorporated into this insulated wire stripper, is positioned to be ready to eject the cut insulation, after the compressed air has been turned on; Figure 15 is a partial vertical sectional view, somewhat similar to Figures 13 and 14, taken along the longitudinal center plane of the insulated wire stripper, illustrating how the slide has been moved, carrying the insulation cutter subassembly, to strip the insulation from the wire, and also showing how the insulation ejector, has been moved, via the contacts with the cam pins, to eject downwardly the cut and stripped away portion of the insulation, after the compressed air has been turned on long enough to create a force to overcome the releasible locking subassembly of the slide to the inner housing; Figure 16 is a partial vertical sectional view taken along the longitudinal plane, nearer the side of the insulated wire stripper, to show how the top and bottom cam pins are positioned, when the insulated wire gripper subassembly is opened to receive an end portion of an insulated wire, before the compressed air is turned on; Figure 17 is a partial vertical sectional view, somewhat similar to Figure 16, taken along the longitudinal plane, nearer the side of the insulated wire stripper, to show how the top and bottom cam pins are positioned, when the insulated wire gripper subassembly is closed to grip an end portion of an insulated wire, after the compressed air is turned on; Figure 18 is a front view of the upper cutter of the insulation; Figure 19 is a side view of the upper cutter of the insulation; Figure 20 is a front view of the lower cutter of the insulation; Figure 21 is a side view of the lower cutter of the insulation; Figure 22 is a top view of the inner slide; Figure 23 is a side view of the inner slide; Figure 24 is a bottom view of the inner slide; Figure 25 is a vertical sectional view of the inner slide, taken along the center thereof; Figure 26 is a front view of the inner slide; Figure 27 is a rear view of the inner slide; Figure 28 is a top view of the inner housing; Figure 29 is a side view of the inner housing; Figure 30 is a bottom view of the inner housing; Figure 31 is a vertical sectional view of the inner housing, taken in the central portion thereof; Figure 32 is a front view of the inner housing; Figure 33 is a rear view of the inner housing; Figure 34 is a top view of the outer housing; Figure 35 is a side view of the outer housing; Figure 36 is a bottom view of the outer housing; Figure 37 is a vertical sectional view of the outer housing, taken in the central portion thereof; Figure 38 is a front view of the outer housing; Figure 39 is a rear view of the outer housing; Figure 40 is a bottom view of the lever which holds and moves the upper cutter of the insulation cutter subassembly; Figure 41 is a sectional view of this lever taken on line 41-41 of Figure 40; Figure 42 is a front view of this lever; Figure 43 is a side view of the cam return pin which is to be connected to the extended piston portion of the compressed air cylinder; Figure 44 is the front view of this cam return pin; Figure 45 is a rear view of this cam return pin; Figure 46 is a top view of the slide and lever control cam to be located between the cam return pin and the lever which moves the upper cutter of the insulation cutter subassembly; Figure 47 is a side view of this slide and lever control cam; Figure 48 is a sectional view of this slide and lever control cam, taken on line 48-48 of Figure 46; Figure 49 is a front view of this slide and lever control cam; Figure 50 is a rear view of this slide and lever control cam; Figure 51 is a top view of the adjustably positioned insulated wire stop holder; Figure 52 is a vertical cross section of the adjustably positioned insulated wire stop holder, taken on section line 52-52 of Figure 51; Figure 53 is a front view of the adjustably positioned insulated wire stop holder; and Figure 54 is a perspective view, with portions cut away, to illustrate how the insulated wire gripper cam pins at their forward ends interfit with the upper and lower insulated wire grippers, and how these cam pins at their rear ends are formed and are positioned in the cam pin block to prevent their rotation, and also the inserted end of an insulated wire is illustrated. A preferred embodiment of a hand held compressed air powered insulated wire stripper 60 is illustrated throughout the figures of the drawings. In Figure 1 this embodiment 60 is shown assembled ready to be connected to a source of compressed air, not shown, via a compressed airline 62, and ready to receive an end 64 of an insulated wire 66. Multiple insulated wire entries 68 are utilized of different sizes to receive respectively differently sized insulated wires 66, such as the three entries 68 illustrated in Figure 1. The operator will place one of his or her hands about an outer housing 70 of this insulated wire stripper 60, in a convenient position, so a finger of this hand will be conveniently used to actuate a depressible lever 72 on a compressed air valve 74, which is secured to this outer housing 70. The operator will use his or her other hand conveniently and quickly to move the end 64 of an insulated wire 66 through one of the entries 68, into and out of this hand held compressed air powered insulated wire stripper 60. The operator's efforts are limited to these less tiring holding, lever moving, and wire guiding, movements, than those movements undertaken, when using hand powered wire strippers. In Figure 2, essentially all of the components of this hand held compressed air powered insulated wire stripper 60 are illustrated spaced apart, with guide lines indicating their subsequent assembly movements with respect to one another. How these components are related to one another, after assembly, in respect to illustrated longitudinal sections thereof, is illustrated in Figures 1 to 7. The Assembling of the Inner Slide, Cutter Actuator Lever, and Cutter Subassembly, etc. As shown in Figures 2 and 5, an inner slide 76 receives a cutter actuator lever 78, via a mounting pin 80 and positioning holes 81. Between this lever 78 and the inner slide 76, a return force coiled spring 82 is positioned in a hole 83 in the lever 78 to keep the lever 78 in a horizontal position. When so positioned, an upper cutter portion 84 of a cutter subassembly 86 is held in its opened raised position, via connecting pins 88, used in securing this upper cutter portion 84 to an operating end 90 of the lever 78. As shown in Figures 2 and 5, a lower cutter portion 92 is positioned for non movement in a front receiving groove 94 of the inner slide 76. Also there are guiding grooves 96, 98, in the front of the inner slide 76, to guide the up and down, or opening and closing, movements of the upper cutter portion 84, upon movement of the cutter actuator lever 78. These cutter portions 84 and 92 are illustrated in Figures 18 to 21. As shown in Figures 7, 14, and 15, the length of the insulation 65 to be removed from an insulated wire 66 to expose the inner wire 67 per a specified length is adjustably preselected by mounting a wire stop subassembly 91 on the inner slide 76, below the forward portions of the cutter actuator lever 78. This subassembly 91 has a plastic body 93, which is secured by fasteners 95 to the inner slide 76, and which positions a metal stop screw 97 to receive the inserted end 64 of an insulated wire 66. After this wire stop assembly 91 has been installed on the inner slide 76, and subsequently, when the inner slide 76 has been inserted within an inner housing 146, then later, when wire stop adjustments are to be made, they are undertaken, after removing a cover plate, not shown, which has been placed over an access opening 101 in the inner housing, using threaded fasteners, not shown, and threaded holes 111 in the inner housing 146. As shown in Figures 2, 5, 41, 43, and 47 the cutter actuator lever 78 has a downwardly facing cam surfaced end structure 100 for interacting with an upwardly facing cam surfaced coupling structure 102 of a two piece flexible coupler assembly 104. One piece 106 of these two pieces, has the cam structure 102 and a collar receiver 108. The other piece 110 has a collar end 112 to be movably received in the collar receiver 108, and an internally threaded end 114 for threaded attachment to a threaded extending piston rod end 116 of a piston rod 118, which moves a piston 117 within a cylinder 120 of a compressed air actuator 122. Another return force coiled spring 121, is placed about this threaded extending piston rod end 116 eventually to be confined between the coupling structure 102 and the front of the compressed air actuator 122. This spring 121 and yet another return coiled spring 123, positioned within the cylinder 120 of the compressed air actuator 122, together axially and longitudinally move back, to their starting positions, the many axially or longitudinally moving components of this insulated wire stripper 60, after an insulation stripping procedure has been completed. As shown in Figures 5, 6, 7, 14, and 15, during either the insulated wire stripping motions or during the return motions, any contact between the one piece 106 of the flexible coupler assembly 104 and the rear end 105 of the inner slide 76, is cushioned by using a resilient shock absorber 107 extending outwardly and rearwardly from a receiving recess 109 on this rear end 105 of the inner slide 76. During this assembling of the inner slide 76, the cutter actuator lever 78, the cutter subassembly 86, etc., the installation of a positive action stripped insulation ejector subassembly 206 is often and preferably undertaken, as later described. The Assembling of the Gripper Closing and Opening Cam, Pins, the Gripper Cam Pins Retaining Block, and the Back End Plate As illustrated in Figures 2, 3, 4, and 54, there are four gripper cam pins extending from the front of this hand held compressed air powered insulated wire stripper 60 to the front locale of the compressed air actuator 122. There are two alike and spaced above, which are called the gripper closing cam pins 124. Then there are two alike and spaced below, which are called the gripper opening cam pins 126. They all have like pin head back ends 128, each having a flat side to contact a transverse positioning bar 129 to keep them from turning, which are positioned in four alike gripper cam pin receiving recesses 130, arranged about a gripper cam pin receiving block 132. Thereafter a back end plate 134 is secured to this gripper cam pin receiving block 132 to hold in place the pin head back ends 128 of all of the four gripper cam pins 124, 126. As shown in Figures 5 and 54, this gripper cam pin receiving block 132 has a central opening 136 slidably to receive the threaded extending rod end 116 of the piston rod 118. Both this gripper cam pin receiving block 132 and the back end plate 134 have threaded fastener receiving holes 138 to receive fasteners 140, which are used to secure them together. In addition the gripper cam pin receiving block 132 has a threaded hole 142 to receive a retaining pin 144, used in keeping the inner housing 146 controllably and slidably positioned relative to this gripper cam pin receiving block 132. Also this receiving block 132 has threaded holes 148 to receive fasteners, not shown, used in securing the outer housing 70 to this receiving block 132. The two gripper closing cam pins 124, positioned above, have forward cam ends 154 arranged on a bias. The two opening cam pins 126, positioned below, have forward cam ends 156 arranged as a slot with one forward slot side arranged on a bias. The cammed ends serve in controlling the closing and opening movements of a gripper subassembly 158. There are cooperating cam surfaces 155, 157 on an upper gripper portion 166. The Assembling of the Previously Assembled Gripper Closing and Opening Cam Pins, the Gripper Cam Pin Retaining Block, and the Back End Plate, With the Compressed Air Actuator, and Also Assemling the Two Piece Flexible Coupler Assembly With the Threaded Extending Piston End of the Piston of the Compressed Air Actuator At this stage of the overall assembly of this hand held compressed air powered insulated wire stripper 60, the back end plate 134, via a central threaded hole 135 thereof, is threaded onto a threaded central front fitting 119 on the cylinder 120 of the compressed air actuator 122. Also the two piece flexible coupler assembly 104, via the internally threaded end 114 of its other piece 110, is threaded on the threaded extending piston end 116 of the piston 118 of the compressed air actuator 122. These interconnections serve to complete the joining of the compressed air actuator 122 to the wire stripping components of this hand held compressed air powered insulated wire stripper 60. The Assembling of the Previous Assemblies Centering on the Assembly of the Previously Assembled Inner Slide, Cutter Actuator Lever and Cutter etc., and the Previously Assembled Gripper Closing and Opening Cam Pins, the Gripper Cam Pin Returning Block and the Back End Plate, etc, by Using the Inner Housing, etc. After assembling the inner slide 76, the cutter actuator lever 78, and the cutter subassembly 86, etc., and after assembling the gripper closing and opening cam pins 124, 126, the gripper cam pin retaining block 132, and the back end plate 134, etc. and securing portions of each respectively to the compressed air actuator, these respective assemblies are fitted together. Subsequently, the inner housing 146 is slidably placed over these assembled earlier assemblies. Then the retaining pin 144 is passed, in part, through a relative travel limiting motion slot structure 159 of the inner housing 146, and secured to the gripper cam pin retaining block 132, to retain them together, while also keeping the gripper cam pins 124, 126, well positioned within this inner housing 146. Assembling of the Gripper Subassembly and the Front Plate having Multiple Insulated Wire Entries As illustrated in Figures 2, 3, 4, 13, 14, 15, and 54, just inside a front end 160 of the inner housing 146 is a front shoulder 162 to position the insulated wire gripper subassembly 158. A bottom or lower insulated wire gripper portion 164 remains in position inside the inner housing 146 near the bottom thereof. The top or upper insulated wire gripper portion 166 via the cams 155, 157 thereof, is moved up to open and move down to close this gripper subassembly 158, upon the respective interactions of the forward cammed ends 154 of the two upper gripper closing cam pins 124, and the forward cammed ends 156 of the lower gripper opening cam pins 126, during the relative motions between the inner housing 146 holding the gripper subassembly 158, and these gripper cam pins 124, 126, secured to the gripper cam pin receiving block 132. After the placement of the gripper subassembly 158 in the front end 160 of the inner housing 146, a front plate 168, having the multiple insulated wire entries 68, respectively to receive and guide insulated wires of different sizes, is secured to the front end 160 of the inner housing 146, using fasteners 170 passing through holes 172 in the inner housing 146 and into threaded holes 174 in the front plate 168. Assembling the Outer Housing in Conjunction With Assembling the Releasible Override Stop Subassembly Which Initially Keeps the Inner Slide Connected to the Inner Housing At this subsequent stage of assembling this hand held compressed air powered insulated wire stripper 60, a releasible override stop subassembly 175 is installed during a period both before and after the placement of the outer housing 70, which will extend over a portion of the inner housing 146. As illustrated in Figures 2 to 8, the bottom sides and bottom of both the inner slide 76 and the inner housing 146 have respective transverse partial receiving slots 176, 178 which are aligned, when these components 76 and 146 are initially positioned to receive the inserted end 64 of an insulated wire 66. When these slots 176, 178 are aligned, and the outer housing 70 has been installed and secured to the gripper cam pin retaining block 132 by using fasteners, not shown, inserted into the threaded holes 148, a transverse control pin 180 is placed in these partial transverse receiving slots 176, 178. This placement of the transverse control pin 180 is initially maintained by a cantilevered flat spring 182 secured at one end thereof, to the bottom of the inner housing 146, by using threaded fasteners 184 passing, in part, through holes 186 in this spring 182 and into threaded holes 188 in the inner housing 146. The bottom of the outer housing 70 has a cut out portion 190 to accommodate the insertion of the transverse control pin 180 and the secure placement of the cantilevered flat spring 182, and the relative movement of this spring 182 within this cut out portion 190, during the relative movement of the inner housing 146 within the outer housing 70. This cut out portion 190 is covered by a cover 193, which is secured by fasteners 195. During the released functional period of the releasible override stop subassembly 175, which commences after the gripping and cutting of the inserted end 64 of the insulated wire, and which continues on through the stripping of the insulation 65 from the wire 67, the free end 191 of this cantilevered flat spring 182 deflects sufficiently to allow the transverse control pin 180 completely to drop clear of the transverse partial receiving slot 176 of the inner slide 76, while remaining, in part, in the transverse partial receiving slot 178 of the inner housing 146, as illustrated in Figures 6 and 7. Assembly of Compressed Air Control Valve and Operating Lever Thereof and Compressed Airlines The compressed air control valve 74 having the finger depressible lever 72 is secured to the outer housing 70 by using fasteners 192 threaded into threaded holes 194 of the outer housing 70 as shown in Figures 1 and 35. One compressed airline 62 extends between this control valve 74 and a source of compressed air, not shown, which will be located in a factory area or other area, where this insulated wire stripper 60 will be used. Another compressed airline 62 extends between this control valve 74 and a compressed air inlet port structure 196 on the cylinder 120 of the compressed air actuator 122. There is a discharge or exhaust air port, not shown, on the opposite end of the cylinder 120 to complete an overall compressed air system 200. The operation of this overall compressed air system 200 commences after the insertion of an end 64 of an insulated wire 66 to contact the wire stop assembly 91, and the finger movement of the control lever 72 of the compressed air control valve 74. This operation then continues during the gripping of the insulated wire 66, the cutting of the insulation 65, the stripping of the insulation 65 from the wire 67, and the removal of the insulated wire 66, with the then stripped end 64 thereof, from this hand held compressed air powered insulated wire stripper 60. Thereafter, upon the reverse movement of the control lever 72, the two coiled springs 121, 123 arranged axially and longitudinally, respectively, about the extending end 116 of the piston rod 118, and within the cylinder 120 of the compressed air actuator 122, become very effective to return the moving components of this insulated wire stripper 60 back to their starting positions, as the compressed air is exhausted via a port, not shown, in the compressed air control valve 74. Before and during this return time, the return force coiled spring 82 has returned the cutter actuator lever 78 to the starting position thereof, raising the upper cutter portion 84 of the cutter subassembly 86. Also before and during this return time, the gripper cam pins 124, 126 have accommodated the raising of the upper or top gripper portion 166 of the gripper subassembly 158. Moreover, during this return time, as the transverse partial receiving slots 176, 178, respectively, of the inner slide 76 and the inner housing 146 are again aligned, the cantilevered flat spring 182 effectively moves the transverse control pin 180, to be partially inserted in each of these transverse partial receiving slots 176, 178. Utilization of a Positive Action Stripped Insulation Ejector Although gravity is often effective in causing a piece 204 of stripped insulation 65, sometimes referred to as a slug 204, to drop out of this hand held compressed air powered insulated wire stripper 60, the incorporation of a positive action stripped insulation ejector subassembly 206 is undertaken, as shown in Figures 14 and 15. A cantilevered ejector 208, formed from a spring wire material 210, is secured at one back end thereof to the inner slide 76, by inserting a bent end, having two downwardly bent spaced legs, not shown, into snap in receiving holes, not shown, of the inner slide 76. A depending end 216 of this cantilevered ejector 208 is downwardly passable through an opening, not shown, in the inner slide 76. Depending and projecting ejector cam screws 220 are threadably inserted down through threaded holes 222 in the inner housing 146, to contact the cantilevered ejector 208 during the extended retracting movement of the inner slide 76 relative to the inner housing 146, after the release of the releasible override stop assembly 175 has occurred. At the conclusion of this relative movement, the depending end 216 of the cantilevered ejector 208 has been quickly and sufficiently lowered to contact and forcibly to eject the piece 204, or slug 204, of stripped insulation 65 completely out of this hand held compressed air powered insulated wire stripper 60. When this positive action stripped insulation subassembly is installed, the installation is undertaken, commencing when the assembling is undertaken of the inner slide 76, cutter actuator lever 78, and cutter subassembly 86. After this assembling is completed and the inner housing 146 has been placed over the inner slide 76, the ejector cam screws 220 will be positioned in the inner housing 146. How the Insulated Wire Gripping, Cutting, and Stripping Components Move After the Time an Insulated Wire End Has Been Inserted and the Compressed Air Valve Has Been Opened As shown in Figure 1, an insulated wire end 64 of an insulated wire 66 is being directed into a selectable insulated wire entry 68. After passing through the selected insulated wire size entry 68, the insulated wire 66 is advanced, until the inserted end 64 thereof contacts the metal stop screw 97 of the wire stop assembly 91, as shown in Figure 14. At this commencing time, there is no compressed air being utilized, and all the return springs 82, 121, and 123, have effectively positioned all the movable components into their initial positions. As illustrated in Figures 3, 5, and 16, the gripper subassembly 158 has been opened, as the two gripper opening cam pins 126, via their forward cammed ends 156, have raised the top or upper gripper portion 166, sufficiently above the stationary bottom or lower gripper portion 164, to provide adequate clearance for the passing of the end 64 of the insulated wire 66. The forward cammed ends 154 of the two gripper closing cam pins have accommodated this opening of the gripper subassembly 158, upon the spring biased full return of both the inner housing 146 and the inner slide 76 to their respective starting positions. At this time the upper cutter portion 84 of the cutter subassembly 86 is being held in the raised position thereof, above the lower cutter portion 92, by the cutter actuator lever 78, as shown in Figure 5. This insertion of the end 64 of the insulated wire 66 is quickly undertaken at all times, even if the wire is not straight, because the entry 68, the gripper opening, and the cutter opening are designed conveniently to receive an insulated wire end 64 which is partially curved and/or partially irregularly curved. The length of the inserted portion of the insulated wire 66 is comparatively kept quite limited by the placement of both the gripper subassembly 158, and the cutter subassembly 86 very near the insulated wire entry 68, which is flush with the front of this insulated wire stripper 60. When the various single insulated wires 66 of a bundle are separated out to be individually stripped, the separated length of each single wire is comparatively kept short, because of this excellent forward placement of the gripper subassembly 158 and the cutter subassembly 86. When the man or woman using this hand held compressed air powered insulated wire stripper 60 has assured himself or herself that the wire end 64 has contacted the wire stop assembly 91, then he or she depresses the lever 72 of the compressed air control valve 74, and the force created moves the piston 117 back through the interior of the cylinder 120 of the compressed air actuator 122, against the force of the two return springs 123 and 121. At the outset of this overall return movement of the many respective retractable components, the inner slide 76 and inner housing 146 are secured together by the transverse control pin 180. They move together relative to the two gripper closing cam pins 124 and the two gripper opening cam pins 126 which are held stationary in the gripper cam pins receiving block 132. During this initial relative movement their respective forward cammed ends 154, 154 cooperate, as shown in Figures 16 and 17, to move the top or upper gripper portion 166 of the gripper subassembly 158, via the cams 155 thereof, into firm contact with the insulated wire 66, which in turn is moved into firm contact with the lower or bottom gripper portion 164, as illustrated in Figure 16. Also during this initial return time, when the inner slide 76 and the inner housing 146 are secured together by the transverse control pin 180, the cutter actuator lever 78 is caused to pivot, against the force of the return spring 82, to move the upper cutter portion 84 down against the insulation 64 of the insulated wire 66, which in turn is moved down against the lower cutter portion 92. The relative motion between these upper cutter and lower cutter portions 84, 92 is limited by their design, as illustrated in Figures 18 to 21, so only the insulation 65 will be cut, as shown in Figure 15, and the wire 67, often coated, will not be scraped, nicked, nor scratched. The cutter actuator lever 78 is caused to pivot as the down facing cam surface 100 thereof, is contacted by the upward facing cam surface 102 of the one piece 106 of the two piece flexible coupler assembly 104, during the retractable movement thereof. The other piece 110 of this coupler assembly 104 is threaded to the piston rod 118, which is integral with the piston 117, being moved inside the compressed air actuator 122, under the force of the compressed air. This quick sequence, being essentially instantaneous, of the insulated wire 66 being gripped, and the insulation being cut is completed, when the inner slide 76 remains in place with respect to the inner housing 146, via the positioning of the transverse control pin 180. Then very soon thereafter, the releasible override stop subassembly 175, via the build up of the overall compressed air pressure, is overridden. The pulling force reaching the inner slide 76 becomes great enough, so the inner slide 76 moves, causing the transverse control pin 180 to be moved out of the transverse partial receiving slot 176 of the inner slide 76, against the retaining force created by the cantilevered flat spring 182, as illustrated in Figure 7. This pulling force reaches the inner slide 76, via the piston 117, the piston rod 118, the coupler assembly 104, and the cutter actuator lever 78. The insulation 65 is quickly removed from the wire 67. Then the momentum of the inner slide 76 causes the inner slide 76 to partially overtake the retracting motion of the coupler assembly 104, as shown in Figure 7. Then at this time, the relative positions of the respective cam 100 on the inner slide and the cam 102 on the coupler assembly 104, make it possible for the operator to withdraw the insulated wire 66 from this insulated wire stripper 60, while the compressed air control valve 74 is still opened, as the lever 72 is still being depressed. Following the stripping of the insulation, the insulation ejector subassembly 206 is effective in ejecting the piece or slug 204 of insulation 65 from within this insulated wire stripper, as illustrated in figure 15. When the insulated wire 66 has been withdrawn, with the end 64 then stripped, the operator moves his or her finger clear of the lever 72 of the compressed air control valve 74. Thereafter, the axial and longitudinally directed forces of the springs 121 and 123 serve to return the moving components to their starting spaces. These springs 121 and 123 are timely and sequentially assisted by the force of the spring 82 pivoting the cutter actuator lever, to continue the opening of the cutter subassembly 86, and by the force of the cantilevered flat spring 182 returning the transverse control pin 180 into the locking position thereof, between the inner slide 76 and the inner housing 146. When the inner housing 146 returns to the starting position thereof, the relative positioning of the gripper subassembly 158, carried by the inner housing 146, with respect to the respective forward cam ends 154, 156 of the respective two gripper closing cam pins 124, and the two gripper opening cam pins 126, completes the opening of the gripper subassembly 158, previously commenced upon the withdrawal of the insulated wire 66. When compressed air enters the front end of the compressed air cylinder 120 of the compressed air actuator 122, the piston 117 is forced toward the rear of the cylinder 120. The piston rod 118 of this actuator 122, via the coupling 104, applies a force on the cutter actuator lever 78. This lever 78, via the mounting pin 80, is connected to the inner slide 76. Therefore this force is also trying to move the inner slide 76 toward the rear of this insulated wire stripper. However, at this starting time, the inner slide 76 is temporarily locked, with the transverse control locking pin 180 to the inner housing 146, and therefore the inner slide 76 cannot move backward independently. At this starting time, since the inner slide 76 is unable to move backward, the force being applied to the cutter actuator lever 78, causes the lever 78 to pivot and thereby to close the cutter subassembly 86, and at this moment cut the insulation 65. After the insulation 65 is cut, the insulation 65 can only be removed from the wire 67, when the insulated wire 66 is held firmly in the gripper subassembly 158, and the inner slide 76 moves, independently of the inner housing 146, toward the rear, while the insulation cutter subassembly 86 remains closed. Regarding the closing of the insulation gripper subassembly 158, the inner housing 146 is always loosely connected to the gripper cam pins receiving or holding block 132, via the retaining pin 144 confined within the relative travel limiting motion slot structure 159. This loose connection permits this cam pin holding block 132 and the compressed air cylinder 120, which is connected to this cam pin holding block 132, to move together. In one embodiment of this wire stripper 60, this movement extends for 4.8 mm (three sixteenths of an inch) inside the inner housing 146. This relative motion, or floating motion, of 4.8 mm (three sixteenths of an inch), also permits the like relative motion of the assembled cam pins holding block 132 and cam pins 124, 126, within the inner housing 146. During this relative motion or floating motion, the gripper subassembly 158 is actuated. The cam portions 154 and 156 on the respective cam pins 124 and 126 interacting with the cam portions 155, 157 on the upper gripper portion 166 will actuate the gripper subassembly 158. When the assembly of the cam pins 124, 126 and the cam pin receiving block 132 moves relatively deeper into the inner housing 146, the gripper subassembly 158 is closed to grip the insulated wire 66. Conversely, when this assembly of the cam pins 124, 126 and the receiving block 132 moves relatively back in the inner housing 146, the gripper subassembly 158 is opened to release the insulated wire 66. This movement in either direction, in one embodiment, is confined within a length of 4,8 mm (three sixteenths of an inch) within the inner housing 146. When the compressed air pressure is applied, after the insertion of the end 64 of the insulated wire 66, then during the starting moments, the inner slide 76 and the inner housing 146 are locked together, via the releasible override stop assembly 175 having the transverse control pin 180 in the locking position thereof. As a consequence, then these locked together inner slide 76 and inner housing 146 are kept from moving backward. Yet the air actuator 122 connected to the back end plate 134, in turn connected to the cam pin holding block 132, in turn connected to the cam pins 124, 126, as an assembly, in effect, moves forwardly to cause the closing of the gripper subassembly 158. Essentially simultaneously, when this gripper subassembly 158 is being closed during this 4,8 mm (three sixteenths of an inch) relative or floating movement, the piston 117 is trying to move to the rear during this 4.8 mm (three sixteenths of an inch) relative or floating movement. But because of holding power of the releasible override stop assembly 175, at this initial operating time, the piston 117, via the extending rod portion 116, and the two piece flexible coupler assembly 104, is only able to pivot the lever 76 to cause the desired simultaneous closing of the cutter subassembly 86 to cut the insulation 65. After this simultaneous gripping of the insulated wire 66, and the simultaneous cutting of the insulation 65, the larger force created during the following increased air pressure operating period, eventually overcomes the holding power of the releasible override stop assembly 175, originally holding the inner slide 76 inside the inner housing 146, whereby the inner slide 76 is pulled back upon the power of the compressed air actuator 122. During this preliminary movement of the released inner slide 76, the cutter subassembly remains closed and the insulation 75 is stripped from the wire 67, while the insulated wire 66 remains tightly held in the gripper subassembly 158. The stripped away insulation 204 is cleared from this insulated wire stripper 60, upon the operation of the insulation ejector subassembly 206. At the end of the rearward motion of the piston 117, the inner slide 76, via the limited longitudinal freedom provided by the two piece flexible coupler assembly 104, is able, via its momentum, to move back farther a small distance. When this occurs, the return force spring 82 positioned in the cutter actuator lever 78 raises the front operating end 90 of this lever 78 to open the cutter subassembly 86. Also at this operational moment in time, there is no force being applied, via the cam pins 124, 126, to keep the gripper subassembly 158 closed, therefore the operator of this insulated wire stripper 60, easily pulls on the insulated wire 66, to clear the finished stripped wire 67 from within this stripper 60. This clearing of the stripped wire 67 is undertaken before the compressed air control valve 74 is operated to stop the supply of compressed air and open the vent, and consequently also before the inner slide 76 returns to the starting position. After the stripped wire 67 is removed, and after the lever 72 on the compressed air control valve 74 is released, the force of the spring 123 inside the cylinder 120 of the compressed air actuator 122, and the force of the additional spring 121 positioned about the extended end 116 of the piston rod 118, combine to cause the return of the inner slide 76 to the starting position thereof. Upon reaching this starting position, the inner slide is again locked to the inner housing 146 by the releasible override stop assembly 176. To avoid any possibility of an overrun by the returning inner slide 76, a steel cam stop pin 224, during assembly of this insulated wire stripper 60, is passed through a slide returning motion control slotted structure 226 of the inner housing 146, made of aluminum, and positioning a vertical steel stop rod 228. Then this stop pin 224 is threaded into place in the inner slide 76, as shown in Figure 8. As necessary, on the return of the inner slide 76, the steel cam stop pin 224 will contact the vertical steel stop rod 228, at the forward end of the slotted structure 226, to control the inner slide returning motion, thereby avoiding possible excessive return motion of the inner slide 76, which otherwise could dislodge the gripper subassembly 158. At this return time to the starting position of the inner slide 76, the cam pins 124, 126 have opened the gripper subassembly 158. Also, the cutter actuator lever 68 has opened the cutter subassembly 86, and the insulated wire stripper 60 is ready to receive another end 64 of an insulated wire 66 to have a piece 204 of insulation 65 stripped from the wire 67. The overall compactness of this hand held compressed air powered insulated wire stripper 60, and its comparatively lighter weight, and its automatic functioning, eliminating the need for hand squeezing motions, can ensure that this hand held tool 60 will be comfortably and efficiently used carefully to strip insulated wires 66.

Claims: A hand held compressed air powered insulated wire stripper, comprising: a hollow outer housing (70); a hollow inner housing (146) which slides inside the hollow outer housing (70); an open top inner slide (76) for sliding movement within the hollow inner housing (146); a cutter actuator lever (78) pivotally positioned on the open top inner slide (76); an insulation cutter subassembly (86) mounted on both the open top inner slide (76) and the cutter actuator lever (78) for cutting action upon movement of the cutter actuator lever (78); an insulated wire gripping subassembly (158) mounted on the hollow inner housing (146) to grip an end of an insulated wire (66) during the cutting of the insulation thereof; a back plate (134) secured to the hollow outer housing (70) and to be secured to a cylinder (120) of a compressed air actuator (122); an extended portion (116) of a piston secured to a piston (117) of the compressed air actuator (122) and positioned and guided by the back plate (134); a two piece flexible coupler assembly (104) interconnecting the extended portion (116) of the piston and the cutter actuator lever (78) at the rear portion thereof, to move the insulation cutter subassembly (86) via the action of the lever arm (78), to cut the insulation (65) off an end (64) of an insulated wire (66), upon the initiation of a retracting movement of the extended portion (116) of the piston, and upon the continued retracting movement of the extended portion (116) of the piston, thereafter retractably to move both the cutter actuator lever (78), while remaining in the position to keep the cutter subassembly (86) in the cutting position, and the open top inner slide (76), as a subassembly, relative to the hollow inner housing (146) thereby to strip the cut insulation (204) off an end of the originally insulated wire end (67), while the insulated wire gripping subassembly (158) mounted on the hollow inner housing (146) continues to grip the inserted end of the insulated wire (66); a positioning cam subassembly (124, 126) extending from the back plate subassembly (134) to the insulated wire gripping subassembly (158) on the hollow inner housing (146), to actuate the insulated wire gripping subassembly (158) to grip an inserted end of insulated wire, upon the initiation of a retracting movement of the extended portion (116) of the piston, and to continue the gripping during the entire stripping movement; and a releasible override stop subassembly (176, 178, 180, 182) to keep the open top inner slide (76) in a commencing position within the hollow inner housing (146) during the gripping of an insulated wire end (66) and the cutting of the insulation (65) of the insulated wire end, and then to be overridden during the stripping of the insulation from the wire. A hand held compressed air powered insulated wire stripper according to claim 1, wherein the compressed air actuator (122) has the cylinder (120) thereof secured to the back plate subassembly (134) and the piston (117) thereof secured to the extended position (116) of a piston. A hand held compressed air powered insulated wire stripper according to claim 1, wherein the compressed air actuator (122) has the cylinder (120) thereof secured to the back plate subassembly (134) and the piston (117) thereof secured to the extended portion (116) of a piston, and has a return spring (123) of sufficient strength to return the piston (117) thereof and all moving components of the insulated wire stripper (60) to initial insulated wire end receiving positions thereof. A hand held compressed air powered insulated wire stripper according to claim 1, including a retaining pin subassembly (144) operable between the inner housing (146) and the back plate subassembly (134) to prevent any unwanted disassembly of the inner housing (146) from the back plate subassembly (134).

Inventors: BUCHMAYER ERNST, BUCHMAYER, ERNST
Applicants: BUCHMAYER ERNST, BUCHMAYER, ERNST
Application year: 1991
Main classification: H02G1
IPC codes: H02G1