Patent GB-716357-A (GB)
Title: Multiple assembling machine for electric blasting initiators
IPC: F42B3/198
Filed: 1952-10-01
Abstract: 716,357. Assembling blasting detonators. ATLAS POWDER CO. Oct. 1, 1952 [Oct. 2, 1951], No. 24561/52. Class 9(1)  Machine for inserting plug and matchhead assemblies in electric blasting caps comprises a member through which extend a plurality of channels, feed mechanisms being provided to insert the plug assemblies and the blasting shells respectively into the opposite ends of the channels where plugging mechanisms effect relative positioning of the shells and assemblies and insertion of the plugs in the shells. Spools or bundles of wires 11 are placed on a tray 10 described in Specification 716,358, wires from each spool being led through a clamping member 13 to a movable guide 15 having arms 16 telescopically mounted in the side walls of the tray and held in the forward position by springs 17. To position the tray 10 in the machine. the tray is provided with front and rear skids, while a lug 24 extending downwardly from each arm 16 determines the extreme forward position of the guide 15, Fig. 39. On the machine frame 40 is slidably mounted a crosshead 41 carrying a yoke 42 mounted to move longitudinally. Slidable on the yoke is a feed table 43, Fig. 1. Plug and match assemblies 44 are connected to the lead wires 11 and the tray 10 is inserted into the machine at A on to the table 43, while loaded shells 45 in a holder are fed to the cross-head 41 at B, Fig. 1, conveyers (not shown) being provided to feed the trays to the machine and to convey them away. The skids of each tray ride over rollers 51 at each side of the feed table 43, the rollers 51 being lower than the table to prevent movement of the trays transversely to the table. The feed table is fastened to a frame 54 with depending tongues engaged in grooves in the yoke 42 so that the table can be moved towards the crosshead. A locking plate 58 is mounted on slides 57 secured between cross-bars of the feed table and may be brought forward to prevent lateral movement of the tray 10 with respect to the feed table. An extension 59 of the plate 58 engages the lug 24 while a resilient latch 63 provides additional locking means for the tray. The tray 10 is ejected from the machine by the subsequent tray fed from the conveyer and as the tray 10 is ejected the rear skid contacts a roller 64 mounted on a lever 65. This lever is pivoted on the frame 40 and has a portion 67, actuating a micro-switch, when the roller is forced downwards by the skid, to allow air to enter a pneumatic cylinder 71, Fig. 5, thus moving the locking plate 58 forwardly with respect to the feed table 43. Forward movement of the plate 58 closes a microswitch 75 in series with three micro-switches 131, 132, 135. When these four switches are closed, air enters a cylinder 76 attached to the framework 40, so driving the feed table forwardly. As the tray 10 is placed on the feed table, a shell holder 80 with openings 81 containing filled shells 45, Fig. 21, is inserted in the machine, openings 82, 83 being provided to position the holder. A conveyer 85 feeds the holders to the machine with the shells 45 vertical, an operator then placing them horizontally on the table 84 between adjustable guide plates 86, 87. The forward guide plate 86 is secured to the table 84, which is locked by means of hand wheels 89 on slides 88. The rear guide plate 87 is bolted to a bracket secured to the slides 88. To adjust the guides according to the size of shell, the hand-wheels 89 are loosened and the table 84 moved to the correct position on the slides. Slidable on the guide 86 is a push rod 93 for inserting the holders in the machine, this rod being adjusted by means of a handle 96. As the rod is moved to the right or left a rod 97 beneath the table 84 moves to engage a hinged plate 98 and so open a switch 99, the rod 97 being held out of engagement with the plate when the push-rod 93 is at the extreme left-hand side of the machine by pressure against an adjustable finger 104 fastened to the rod 97. Thus the switch is held open and operation of the machine is prevented while the holders are inserted. The switch 99 is in series with a switch 106 at the rear of the machine and when the both switches are closed a safety screen 107 of sheet metal descends over the machine, Fig. 5. An inspection window 108 is provided in the screen which is raised pneumatically by means of a cylinder 112 connected to a cable 113. A counterweight 116 mounted in slides 117 is secured to the cable at the forward end of the machine. The rod 93 moves the holder 80 into a slot in a carriage 120 adjustable on the crosshead 41 where a plate 122 prevents lateral movement of the holder relative to the carriage. The carriage 120 is adjustable on the yoke 42 to accommodate. various sizes of shells, Pivoted on the carriage is a positioning bar 125, Figs. 1 and 13, associated with means to lock the holder 80 in place and prevent operation of the machine if the holder is empty. The bar 125 extends over a roller 127 mounted on a bellcrank lever 128 which is caused to pivot, and so raise the bar 125, by the insertion or a holder 80 in the carriage, Fig. 13. The bar 125 carries plungers 129, 130 which enter the openings 82, 83 in the holder to lock the holder in position. The plunger 130 when in the opening 83 bears against the shell in an opening 81 below. If there is no shell in the opening the plunger drops into the opening 81 and a normally closed switch 132 is opened, while if the plunger 129 contacts a shell an open switch 131 is closed, thus indicating the presence of shells in the holder. When the switches 75, 131 and 132 are closed the shells and plug assemblies are correctly placed and lowering of the screen 107 closes a switch 135 and air enters the cylinder 76. After a capping operation, insertion of a second holder in the carriage 120 raises the bar 125 and allows withdrawal of the first holder. The ejected holder is gripped between an upper driven roller 136 and lower idle rollers 137 covered with soft material to pull the holder free of the machine and deliver it to a conveyer. These rollers are supported on a framework 139 together with a motor 138 driving the roller 136, Fig. 1. As air enters the cylinder 76 the feed table 43 moves forwards and the plug assemblies 44 are directed by the guide 15 into funnels 140 in a block 141, the guide being positioned by pins 142 extending into openings in the guide, Figs. 1, 29, 41. A dash-pot 144, Fig. 6, carried by the bracket 73 and regulated by a valve 147' slows the forward movement of the feed table. If the plug assemblies are not properly positioned in the funnels, the operator may retract the feed table 43 by closing a switch 148. A micro-switch 149 is then closed momentarily, and the screen 107 raised to give access for alignment of the plug assemblies. To complete the assembling operation the operator closes a switch 151 in series with switches 251, 252. When switches 151, 251, 252 are closed, air enters a cylinder 152, Figs. 2, 3, 5, and brings holding means into contact with the rear ends of the plugs, the feed table 43 and yoke 42 being in their forward positions. On the piston rod of cylinder 152 is a rack 153 held in engagement with a pinion 156, Fig. 1, by a roller 157. The pinion is mounted on a transverse shaft 158 carrying cams 159 which engage rollers, Fig. 5, mounted on a plate 162 resiliently supported by springs. The plate 162 abuts the funnel block 141 and has openings 164 aligned with the funnels 140, so that when the cams 159 are rotated by upward movement of the rack 153, the plate 162 moves downwardly to grip the plugs between the upper surfaces of openings 164 and the lower surface of funnels 140; Fig. 29. Simultaneously, air enters the cylinder 71 to return the locking plate 58 to its rearward position. On actuation of cylinder 152 a rod attached to a bell-crank lever is moved forwardly to close a switch 168 and so actuate a cylinder 169, which is pivoted on a bracket 171 at the base of the machine. The cylinder 169 is connected by a toggle 173 to a clevis 177 adjustably connected to the yoke 42, so that as air enters the lower end of cylinder 169 the toggle 173 rotates counter-clockwise and raises the forward end of each clevis 177 to force the yoke 42 rearwardly. By this means the loaded shells are inserted in the funnels 140 and two pins 182 extending through the side arms of the yoke 42 are brought against the guide 15 and force it rearwardly relative to the block 141 and the tray 10. On loosening bolts 124 the carriage 120 may be moved relative to the yoke 42 by rotating screws 185 which carry gears 189 meshing with gears 188 at the end of adjusting screws 186, Fig. 1. Each screw 186 is threaded into a latch block 187 which blocks remain stationary relative to the crosshead when the screws 185 are rotated, since the screws 186 rotate by an equal amount in the opposite direction. Each screw 185 carries a sprocket wheel 191 over which passes a chain 192, so that as one screw 185 is rotated the opposite screw 185 is rotated by the same amount. As the yoke 42 moves rearwardly a switch-operating member 203 on a rod carried by a depending bracket 201 closes a switch 204, Figs. 5 and 6. Air then enters a cylinder 205 and a cam plate 206 moves rearwardly. The plate 206 has a horizontal part 207 with a vertical member 208 at each side in which is a cam track 211 receiving a cam follower 212, Figs. 6 and 13. A second cam follower 213 engages a cam track on the lower surface of members 208. The followers 212, 213 move from lower to upper limit positions as the plate 206 is moved rearwardly. Vertical movement of the cam plate 206 relative to the machine is prevented by rollers 215, 216. As the cam plate 206 moves rearwardly a switch 219 is closed and air enters the upper end of cylinder 152 to force the rack 153 downwards and disengage the cams 159 from the plate 162 thus releasing the plug assemblies. Simultaneously the