Patent GB-716359-A (GB)
Title: A wire insertion machine, in particular for blasting initiator wires
IPC: F42B3/198
Filed: 1953-04-14
Abstract: 716,359. Mounting wires in resilient plugs. ATLAS POWDER CO. April 14, 1953 [May 9, 1952], No. 10133/53. Class 108(3) [Also in Group XXI] A machine for inserting pairs of lead wires in resilient plugs as a stage in the assembly of electric blasting detonators is shown in Fig. 1. A wire jig 10, as described in Specification 716,358 supporting the wires is fed to a machine at A, Fig. 2, and placed on a feed table 42. Resilient plugs .43 in. a holder 44, Fig. 30, are inserted in the machine at B. At each side of the feed table 42 are rollers 45 on which ride skids attached to the base of the jig 10, as the jig is fed into the machine. The jig entering the machine at A forces the jig already in position, which carries assembled wires and plugs, off the table 42 on to a conveyer (not shown). As the jig 10 leaves the table it passes over a roller 46 mounted on an arm 47 which then rotates to close a switch 52, Fig. 1. Closing of the switch 52 operates a pneumatic cylinder 53, Fig. 8, to move a locking plate 54 into engagement with a lug 17, projecting downwardly from the incoming jig. The plate 53 and a spring- pressed latch 57 at the feed end of the table prevent lateral movement of the jig relative. to the feed table, while longitudinal movement is prevented by the skids 22, 23. The feed table 42 is mounted on a frame 60 which can move longitudinally along spaced tracks 61 having grooves 62 to receive tongues extending from the frame 60. The frame 64 carrying the locking plate 54 is moved longitudinally on tubular slides 65 by the piston rod 66 of the cylinder 53, Figs. 2 and 8. A bracket 68 depending from the frame 64 carries a roller 69 which holds a switch 72 open when the locking plate 54 and feed table 42 are in their rearmost position. Secured to the feed table frame 66 is the piston rod 74 of a double-acting cylinder 73. In series with the switch 72 is an operating switch 76 and a switch 91 which is closed when the plug holder is correctly positioned. As the trav 10 is moved forwardly by the piston 74 index holes 77 in the guide 15 holding the wires are brought into engagement with pins 78, Fig. 15 (not shown), the locking plate 54 and guide 15 are then held stationary while the feed table moves to its forward limiting position for insertion of the wires in the plugs. The plug holders, which are placed on a feed table 81, Fig. 2, have openings 82 to receive the plugs, each opening having recesses into which the plug expands as needles and tubes enter the plugs. A push block carried by a guide rail 83 bears against a plug holder 44 placed between the rail and, a face plate 85 on the feed table to insert the holder into the machine through an opening 86, Fig. 1. Aligned with the opening 86 is a lifting plate 88 which receives the holder as it is inserted. The holder 44 depresses a plunger 92 to close the switch 91 which is in series with switches 72 and 76 so that the feed table 42 may move forwards when switch 76 is closed. For purposes of adjustment a manually operated switch 94 is provided adjacent the switch 76, Fig. 4. By operating the switch 94 the stroke of cylinder 73 is reversed and the feed table retracted to allow of adjustment of the wires in the plugs. To complete the insertion operation a manual switch 95, Fig. 4, is closed to cause a camshaft to rotate, Figs. 2 and 6. In series with switch 95 is a switch 97 which is closed by a finger 98 depending from the feed table frame 60, when the feed table reaches its limiting forward position, Fig. 8. In Fig. 3 (not shown) an electric motor 100 is connected by a belt drive to the camshaft 96, a gear reducer 105, and a clutch-operating member 106 being interposed in the drive between a brake drum 111 and a pulley 102 on the high-speed shaft 104 of the gear reducer. The switch 95 controls a double-acting cylinder 114 which moves the member 106 along the high-speed shaft 104 to engage either the puley 102 or the brake drum 111 with the shaft 104 respectively to rotate and stop the camshaft 96. Before insertion of the wires, the plugs 43 are expanded by tubes 130 carried by blocks 147, Figs. 34 and 8. A cam 132 mounted on the shaft 96 engages a follower on an arm 135, mounted on a transverse shaft 136 which is connected by turn buckles 140 to a tube crosshead 139. The crosshead is slidably mounted on the machine frame, so that as the cam 132 begins to rotate the crosshead moves to the right of Fig. 1 carrying with it a plate 145 slotted to receive the blocks 147, Fig. 8, and thus the tubes 130 are withdrawn from the plugs 43. The plugs and wires are assembled in a split funnel plate 155, Figs. 4 and 34, made in two parts 153, 154 which separate when the tubes 130 are withdrawn from the plugs to allow withdrawal of the plugs. The parts 153. 154 are connected to push rods 163, 164, Fig. 4, constrained to move in opposite directions by a cam 168 on the shaft 96, Figs. 1 and 2. which engages a follower on an arm 173 connected by a rod 175 to the push rods. Operation of the machine is stopped if the funnel -plate is not fully closed by two switches 178, 179 (not shown) which, when closed. cause disengagement of the clutch. On opening of the funnel plate 155 ejector rods 181. Figs. 1 and 2, advance to force the jig 10 rearwardly and so withdraws the wires with the plugs mounted thereon from the holder 44. At the same time the cam 132 moves the tubes 130 forwardly to help remove the plugs from the holder. A cam 182 on the shaft 96 engages a follower on an arm 183 fixed to a shaft 185 connected to the rods 181 by arms 186, Fig.. 1, so that as the shaft 96 rotates the rods move forwards. Attached to the cam follower arm 183 is a bracket 188 hinged to a. rod 189, so that as the arm 183 rotates counter-clockwise, the rod 189 moves to the right, Fig. 1, closing a switch 192 which actuates the cylinder 53 to retract the locking plate 54 and free a guide on the jig. Further movement of the rod 189 closes a switch 194 to actuate the cylinder 73 and so retract the feed table 42. The cam 132 then causes retraction of the tubes 130 and cam 168 brings about the closure of the funnel plate. The plate 88 is then raised to place a loaded holder 44 in alignment with the funnel plate, the loaded holder on the plate forcing the other holders upwardly by an amount equal to the height of one holder, Fig. 8. On the shaft 96 is a cam 196 driving the plate 88 through arm 197, links 202 and a rod 203 mounted in the plate frame 204, Figs. 1 and 6. The frame 204 slides in vertical guides 205, Fig. 6. As the plate rises the holder 44 bears against cam surfaces 211, 211 of latches 212, 212 forcing the latches to retract, springs 214, 214 being provided to return the latches, when the plate 88. is lowered, to support the holders. After a holder 44 is aligned with the funnel plate 155, pairs of needles 215 are moved forwards to pierce the plugs, Figs. 2, 8 and. 34. The needles which normally extend through the tubes 130 are secured in a block 216 fastened to a crosshead 217 actuated by a cam 218 on the shaft 96.. As the needles enter the plugs. Fig. 39, the cam 132 moves the crosshead 139 to the left, Fig. 1, so that the tubes 130 move with the needles until both the needles and plugs enter the openings in the funnel plate 155. By the end of the forward stroke of the needles and tubes, the plugs are transferred from the needles to the tubes. the forward end of each tube coming to rest against shoulders 233 in the funnel plate so that continuous paths are provided through the plate and tubes for insertion of the wires At the same time pusher rods 234. Fig. 8, transfer the uppermost empty holder 44 from the machine to a conveyer 235 which carries the holderto a discharge shoot (not shown) and is driven by a motor 235b, Fig. 4. Further rotation of the cam 218 causes retraction of the needles, leaving the plugs on the tubes 130 and cam 182 causes retraction. of the ejector rods 181, 181. At the end of the stroke of rods 181, the rod 189 closes a switch 239, Fig. 1, to reverse the stroke of cylinder 114 and hence operate the brake 111 to halt the camshaft 96. This completes the cycle of operations leaving a loaded plug holder aligned with the funnel plate with tubes inserted in the plugs. by closing the switch 76 the operator starts a new cycle in which the feed table is advanced and the wires carried by the jig are inserted in the tubes 130. The operator then closes switch 95 to rotate the camshaft 96. Thereupon the tubes 130 are withdrawn from the plugs and the plugs transferred to the wires. The plate 155 divides and the tubes 130 and ejector rods 181 advance to force the jig 10 rearwardly, thus removing the plugs from the holder. The tubes 130 are then retracted and the plate 88 moves a loaded plug holder in to alignment with the funnel plate to begin the assembly of a new set of plugs and wires. The double-acting pneumatic cylinders are controlled by pairs of solenoid-operated valves, the solenoids being connected to circuits similar to those described in Specification 716,357, [Group XXI]. Specification 656,008 also is referred to.