GB823171A - Machine for automatically cutting out button roundels from sheet material - Google Patents

Abstract

823,171. Button-drilling machines. BOEHME & CO. Sept. 2, 1957 [Jan. 7, 1957], No. 27601/57. Class 83 (3). An automatic machine for drilling buttonblanks from sheet - stock 43 with a hollow drill 15 comprises means for traversing the work intermittently in a horizontal direction, reversing the direction of traverse, and indexing the work downwardly at the ends of the horizontal strokes. The stock 43 is gripped by a clamp 23 on a carriage 25 having rollers 24 engaging a rail 18 fixed to a tubular saddle 19 which is guided, by a roller-guide on rails 28, for movement on a post 17 upstanding from the machine-base 1. An endlesschain 22 on the saddle 19, and connected to the carriage, is driven by a reversing electric-motor 20, driving through a reduction worm-gear 42 and a clutch which slips when the carriage is held by engagement between one of a pair of dogs 30 on the saddle and a pair of toothed-bars 26 on the carriage. An electromagnet 31, energized by a switch 39 operated by adjustable cams 8 on a cam-shaft 5, lifts the dogs 30, permitting the carriage to be traversed horizontally by one tooth of the operative-bar 26 before a switch 38, operated by the armature of the magnet on reaching the top of its stroke, de-energizes the magnet, thus allowing the dogs to be returned by springs (Fig. 3, not shown). Stops 36 on the carriage operate, at each end of the carriagestroke switches 37 controlling reversal of the motor 20. The teeth of one bar 26 are staggered by half a tooth relatively to those of the other bar, permitting full use of the stock. A further electromagnet (not shown), withdraws a dog from a stationary, vertical toothedrack 27 and allows the saddle 19 to fall by one tooth of the rack against the restraining force of a partial balance-weight 32. The camshaft 5 is driven by an electric motor, through an infinitely variable belt-gear 3 and a wormgear 4, which may be rotated by a hand wheel 41, and has a cam 6 for feeding the drillspindle 13 against the force of a return-spring. A non-rotatable-tube 16 in the drill 15 is formed with teeth to engage the stock, which is steadied by guides 33, 34. The spindle is rotated by an electric motor 9, driving through a V-belt 10 and a belt 12 on a long pulley, and the machine is stopped automatically (not described), at the end of the last row of blanks.