GB903624A - Improvements in and relating to plants for the stacking of sheet metal - Google Patents

Abstract

903,624. Stacking metal sheets. UNGERER, F. July 19, 1960 [Jan. 29, 1960; March 22, 1960], No. 25113/60. Addition to 888,350. Class 100 (1). [Also in Group XXX] A plant for the stacking of sheet metal in accordance with the parent Specification is modified in that the suction heads 7-11 are capable of being connected by a throw-over valve 52 alternatively to a source 54 of suction and to a source 56 of pressure at least equal to that of the ambient atmosphere and are controllable by a device containing an impulse generator, a delayed-action relay 44 and a control member 46 therefor connected to the throwover valve, the time lag of the delayed-action relay being adjustable. In the schematic circuit of Fig. 3, a radiation receiver 42 is shown connected to a control device 45 which is connected both to the delayed-action relay 44 and to a timing relay 51, each of which relays is connected to an actuating member 50 for the valve 52. The radiation receiver is mounted above the lower run of the perforated conveyer 3 and a radiation emitter 43 is mounted below the lower run of the conveyer. The relay 44 is manually adjustable through the control member 46 so as to accommodate variations in the length and weight of the sheets being stacked, and is automatically adjustable by means of a governor 48 driven from the conveyer 3 to accommodate variations in the speed of the conveyer. The relay 51 is adjustable manually. In operation, the leading edge of a sheet 16 picked up by the conveyer 3 intercepts the radiation beam from the emitter 43 and this causes the radiation receiver 42 to emit an impulse, which is, however, suppressed by the control device 45. When the trailing edge of the sheet passes over the emitter 43 the receiver 42 emits a second impulse which is transmitted by the control device 45 to the delayed-action relay 44. After an appropriate interval, determined by the adjustment of the relay 44, the latter relay operates the actuating member 50 and the member 50 actuates the valve 52 so as to disconnect the heads 7-11 from the suction source 54 and connect them to the pressure source 56 whereby the sheet is deposited on a table 18 of the type described in the parent Specification. The second impulse from the receiver 42 is also transmitted to the timing relay 51 which, after an appropriate delay to allow the sheet to fall clear of the conveyer, operates the actuating member 50 a second time so that suction is applied to the heads 7-11 once again. The governor 48 may be replaced by a revolution counter or a speedometer.