GB1167094A - Sheet Metal Press. - Google Patents

Abstract

1,167,094. Stamping. P. E. F. JACQUEMARD. 3 Oct., 1967 [14 Nov., 1966], No. 44967/67. Heading B3Q. A press comprises a plate 46 carrying the upper part 53 of a die and hooks 64 pivoted on the plate for engaging the under side of a lower plate 60, thus locking together the parts 53, 54, 59 of the die while a workpiece is calibrated hydraulically therein. An upper plate 41 mounted on the press-ram 40 has piston-andcylinder units 43 supporting the plate 46, a central unit 51 for operating a plunger 49 and outer units 70 for operating the hooks 64. A retaining ring 56 for holding together the sections of the divided die 54 is carried by a base 58 supported on an air cushion, the base section 59 of the die resting on a seating 61 on the lower plate 60. Operation.-The blank 78, filled with water, is lowered in the die 54 until this is clamped in the ring 56. Further lowering of the ram carries the upper die 53 against the flange of the blank and the base of the blank against the lower die 59. The blank is then deformed to fit the dies, Fig. 2 (not shown). At this stage, plate 46 stops and further downward movement of the ram 40 and plate 41 forces oil out of the cushion cylinders 43 and closes the hooks 64 on to the plate 60. During deformation, water from the blank raises a piston 48 surrounding the plunger 49. The blank is calibrated hydraulically by the plunger 49, the volume being controlled by cams (80), Fig. 3 (not shown). When the ram 40 is raised, the assembly moves upwards until base 58 is stopped by the table 76. Continued movement releases the hooks 64 and withdraws the die 54 from clamp ring 56. A plate 55 carrying the die 54 may be swung clear of the ram by a fluid-pressure control to facilitate loading.