| 摘要 |
1320252 Forging machines NATIONAL MACHINERY CO 3 June 1971 [26 June 1970] 18851/71 Heading B3H A multi-die forging machine comprises a main frame 10, an auxiliary frame 18 pivoted to the main frame about an axis 21 and a slide 22 movable on the auxiliary frame 18 and carrying workpiece gripper assemblies to transfer workpieces between the dies. The frame 18 is pivoted against the action of a fluid spring 124 by a cam 111, Fig. 4, on a cam-shaft 26 which also has a set of cams 82, Fig. 5, which each vertically reciprocate an operating rod of each of the gripper assemblies 23, Fig. 6, respectively by means of a pivoted forked member 102 which acts on the rod and moves it through a rotatable sleeve 31 against the bias of a fluid spring 41. The gripper assemblies are mounted on trunnions 24 of the slide 22. The sleeves 31 each carry a pair of pivoted fingers 47, 49 actuated by the downward movement of the rod which contacts extension arms 77, 78 of the fingers. The upper part of each sleeve carries a gear segment 39, which engages a fixed rack (57), Fig. 1 (not shown), on the auxiliary frame 18 so that the finger assembly is rotated as the slide moves to reverse a workpiece before it enters the next die. Each sleeve 31 can be locked against rotation if desired and the segments are then rotated to an inoperative position. An alternative gripper assembly, Fig. 8 (not shown), has wider spaced fingers 161, 162 for larger workpieces. The fingers are urged towards each other by a fluid spring 163 and have no means of rotation. The slide is reciprocated by a separate cam drive 131, Fig. 9a, through a rack and pinion 143 and an overload clutch 142, 144 to a crank arm 147 connected by a rod 156 to the slide. The rack and pinion are housed at one end of a fluid spring 138 which is pivoted to the machine frame at the other end 141. The spring and the rack and pinion can thus be moved away from the clutch 142, 144 against spring 148 bias if overload occurs due to jamming of the slide. The slide is easily removed for replacement by simply pivoting the frame 18 upwards. In operation the cam drive 131 for the slide and the cam-shaft 26 for the auxiliary frame 18 and the operation of the fingers are synchronized with the machine cycle so that between forging strokes the fingers grip a workpiece ejected from the die, the frame 18 pivots to move the workpiece away from the die and the slide is moved to bring the fingers in line with the next die. The frame 18 then pivots to bring the workpiece nearer to the die and the fingers open. The fingers may rotate the workpiece during transfer. |
