Patent GB-605601-A (GB)
Title: Machine for cutting bungs from sheet material
IPC: B23Q1/48
Filed: 1945-12-31
Abstract: 605,601. Drilling-machines; drills and cutters. SPORING, P. A., PURSE, J. W., and TELEGRAPH CONDENSER CO., Ltd. Dec. 31, 1945, No. 35246. [Class 83 (iii)] [Also in Group VIII] A machine for cutting bungs from sheet material such as rubber is constructed with a table 13 upon which the sheet is mounted, with a cutter 6 formed as a hollow cylinder having a cutting edge, and with automatic means for moving the table 13 after each bung is cut by an amount sufficient to bring an uncut area beneath the cutter at the succeeding cutting operation. The cutter 6 is mounted similarly to a drill and is depressed to effect the cutting operation by a rack 8 operated by a pinion 7 rotatable against the action of a spring by a chain 24 connected to a lever 25 oscillated by a cam on a shaft 22 which controls the main actions of the machine. The table 13 is supported by a carriage 15 which is moved longitudinally stepwise on rods 14 while a number of bungs are cut, and then the carriage is moved transversely on rods 17 and the longitudinal motion is reversed to enable another row of bungs to be cut preferably in a position staggered in respect to the prior row. The stepwise motion is effected by a rack 57 on carriage 15 engaged by a pinion 55 having an adjustable lost-motion connection with its driving-shaft 51 which is driven by bevel gearing from a shaft 30 which is rotated intermittently by ratchet mechanism operated from an adjustable crank-pin-on the shaft 22. When the carriage 15 is given a transverse movement the shaft 30 is moved axially to bring a different bevel gear into engagement with the gear 50 so as to reverse the drive to the shaft 51. The transverse movement is controlled by the engagement of the carriage 15 with adjustable lugs 59 on a rod which operates a lever 67 which normally holds from rotation a drum 62 and gear 63 due to frictional connection with shaft 22. The lever 67 normally engages a raised portion between two slots 64, Fig. 7, on the drum 62, but is freed by a lug 59 and permits rotation of gear 63 for one revolution. The gear 63 operates a shaft with an adjustable crank-pin for operating rotatable mechanism to advance a shaft 86 having a pinion which engages a rack fixed to the carriage 15, and thus the carriage is moved to bring a fresh row of material into operative position. The cutter, Fig. 8, is formed of a cylinder 122 with a hollow conical cutting core 123, and is carried by a spindle 124 connected to the spindle 5. A pointed central pin 125 may be provided for forming a central aperture in the bung, and the cut bung is finally stripped from the cutter by a block 126 movable relatively to the cutter. The block 126 is filled with a pin 128 movable in slots 127 in the cutter and rollers 129 are fitted on the pin 128 and by engaging a fixed plate 131 cause the stripping action. The bungs are received in an aperture in an arm 133 which is swung to carry the bungs to a receptacle into which they are delivered upon opening of a spring-pressed plate 143 which normally closes the aperture. The machine is stopped automatically by the transverse motion of the carriage 15 after the last row of bungs is cut, by engagement of an adjustable arm 119 on the carriage with a trip bar 109 formed with a catch 117 which normally holds a clutch lever 118 in active position. The bar 109 may be operated by hand to stop the machine at any time.