IMPROVEMENTS IN OR RELATING TO APPARATUS FOR CUTTING LENGTHS OF RUBBER OR RUBBER-LIKE MATEFROM STRIPS OR SHEETS

摘要

988,694. Cutting rubber. DUNLOP RUBBER CO. Ltd. Sept. 22, 1961 [Oct. 5, 1960].. No. 34079/60. Heading B4B. [Also in Division B7] An apparatus for severing a length of rubber from a strip and supplying it to a tyre building former comprises a rotatable cutter 11, Fig. 1, having a helically disposed blade 14 coacting with a fixed blade 10, a guide channel 27 for feeding the strip tangentially to the cutter, and means to rotate the cutter. The strip is fed into the channel 27 by a knurled feed roller 41 over freely rotatable rollers 33-35 carried by side members 6, 7 of a frame 1 movable about a pivot 2 by a pneumatically operated rod 3. A sprocket wheel 44, rotatable in each direction by a chain connected at each of its ends to one of a pair of pneumatically operated piston rods controlled by a switch 69 actuated by a feeder roller 71, is drivably connected to the feed roller 41 through a ratchet 45 and to the cutter 11 through gearing 46, 49 and a ratchet 50. A pressure roller 72 on a bell-crank 73 is urged by a spring 78 into contact with the strip when the frame is in its lower position and moved out of contact therewith by the action of a pin 76 when the frame is raised. In operation, with the frame in its lower position, strip is fed by the roller 41 to a roller 29. The frame is then raised to release the pressure roller 72 and bring the roller 29 into contact with the tyre carcass on the former which is then rotated and draws the strip on to the carcass. When the leading edge of the strip contacts the roller 71 the switch 69 is operated to actuate one of the pneumatically operated piston rods to rotate the cutter which severs the required length of strip to form the tread. The former is then again rotated to draw the remaining length of tread strip on to the carcass. The frame is finally returned to its lower position and the other pneumatically operated piston rod is actuated to rotate the roller 41 and recommence the cycle. The roller 41 and the cutter 11 each make one complete revolution during each cycle of operations and are angularly located by spring-loaded stops 52 and 53 respectively. The sequence of operations may be carried out automatically after the inititation by an operator. The former may be rotated while the cutter is operating to obtain a diagonal cut.