Patent GB-865600-A (GB)
Title: Improvements in or relating to machine tools
IPC: B26D1/00
Filed: 1959-10-23
Abstract: 865,600. Splitting-machines. REICHERT, K. Oct. 23, 1959 [Oct. 30, 1958], No. 35947/59. Class 31 (1). [Also in Group XXIII] In a machine comprising a band cutter 20 for cutting plates from a block 91 of foamed material and in which the feed of the cutter, or work, is controlled by a revolution counter 87, Fig. 3, having an adjustable selecting register driven by a shaft 60 of the feed mechanism in such a manner that the feed motion of the cutter, or work, is stopped by an arrester mechanism when the pre-selected number of revolutions has been performed, the traversable work-table 44, or cutter, is provided with adjustable shoes 51, 51a co-operable with limit switches 52, 53 and 54 which act, inter alia, to reverse the direction of rotation of the shaft of the feed mechanism and to release the arrester mechanism after a predetermined period of time. The pulleys for the band cutter are mounted on slides 16, 17 which are fed by means of screwed spindles 27 driven by a feed shaft 30 controlled, according to the position of a lever 32, either by a hand wheel 31 or by mechanical feed means. Limit switches 39, 40, Fig. 1, control the upper and lower positions of the slides 16, 17. The table 44 is traversed by means of a rack 45, Fig. 2, co-operating with a pinion 46 driven by a motor 49. The mechanical feed means for the cutter are controlled by means comprising a rotary magnet 58, Fig. 3, which drives a lay shaft 60 geared to the feed shaft 30. The shaft 60 has mounted thereon arrester plates 67, 68 provided with peripheral cams with which cooperate spring-influenced pawls 71, 72 fulcrumed on a shaft 73. The pawls are arranged respectively to arrest the shaft 60 in each direction of rotation thereof and in such a way that in both directions of rotation, the shaft will be arrested in the same position. Shaft 73 also carries a spring-influenced deflectable lever 76 connected to a plunger 79 which works in a solenoid 81. The shaft 60 drives the counter 87 which comprises a principal counter with a register 88 and a setting register which is coupled with the principal counter and upon which the desired numbers can be manually set up in such manner that the running principal counter, upon reaching the manually pre-set number, actuates a switch for stopping the counter drive. The setting register is equipped with an electrical device which automatically zeroizes the principal register when the counter drive stops. Before the machine is started up, the setting register of the counter is adjusted to the required number, say n, of revolutions. The magnet 58 is then energized and motor 49 switched on in that direction of rotation which will cause the table 44 to return to the right-hand position shown in Fig. 1 in which the shoe 51 will operate switch 52. This causes solenoid 81 to be energized to release the arrester plates 67, 68. The magnet 58 will therefore start turning shaft 60. The cutter is fed down towards the work until shaft 60 has completed n revolutions. The principal register will now read n and the setting register zero. The counter switch then closes and, on the one hand, interrupts the circuit to solenoid 81 and, on the other hand, causes motor 49 which had been stopped by switch 52 to be re-started in the opposite direction. Thirdly, the counter switch will zeroize the principal register and restore the setting register to n. The working operation is now performed by the traverse of table 44 into its other end position. In this position, shoe 51a operates limit switches 53, 54 which cause the magnet 58 to reverse. Switch 54 re-energizes solenoid 81 holding this circuit for a given period of time by means of a time relay in switch box 55. During this period, the cutter and its supporting slides will be raised. At the end of the time determined by the time relay, solenoid 81 is again de-energized and shaft 60 again arrested, motor 49 being started up in the direction of rotation which causes the return of table 44 to its right-hand end position in Fig. 1. During this traverse, the cutter will not contact the face of block 91 from which a section has just been cut off. As soon as shoe 51 re-operates switch 52, the magnet 58 reverses and the reenergization of solenoid 81 releases shaft 60 which will therefore revolve until the shaft is again arrested and the exact position reached for making a new cut. If it is desired that the machine should perform the return traverse before the cut-off part of the work is removed, the delay time of the time relay is prolonged sufficiently to ensure that the cutter will clear the separated part which is still on the work.