1,195,073. Compacting metal powders. J. HALLER. 7 Nov., 1967, No. 50582/67. Heading B5A. [Also in Division F2] General arrangement, Fig. 1.-A metal powder compacting press comprises a die table 34, supporting a die 42, and lower and upper platens 56, 58 which respectively carry a series of concentric lower plungers 48, 50, 52 and a core rod 54, and concentric upper plungers 60, 62; the platens being secured to the outer plunger. The die table 34 is supported by the piston-rods 36, of four hydraulic cushioning devices 30 which permit lowering of table 34 at a predetermined loading pressure and by means whereof the table 34 is returnable to a starting level 35 in abutment with stops 40. The table 34 and platens 56, 58 are slidable on two guide rods 32. The die plungers are independently actuatable in either direction by the engagement, at threaded extensions of each thereof, of a worm rotated nut, the drive to each nut being provided by outlet shafts from lower and upper reversing gear-box units 14, 16 respectively embodying reversing magnetic clutches (see Division F2). The die is filled with metal powder from an open ended box (66) (Fig. 2, not shown) which slidingly reciprocates across the die table 24 into and out of filling alignment therewith by a motor driven screw and nut mechanism. The core rod 54 is actuated independently of the plungers at a threaded lower extension thereof by the engagement of a nut rotated by a worm drive from a reversible electric motor 190. Moulding operation, Fig. 8.-With the die table 34 at its uppermost starting level 35 and the upper and lower plungers retracted, the die is filled. The upper plungers 60, 62 enter the cavity whilst core rod 54 moves above the die surface 46 to enter the bore of the inner upper plunger 62. Continued movement of upper plungers 60, 62 forces down the die table 34 as the cushioning devices 30 yield. With the upper outer plunger 60 stationary the upper inner plunger 62 continues movement as inner lower plunger 52, moves upwardly to complete the compression operation. To eject the moulding, the upper platen 58 and plungers 60, 62 are retracted and the cushioning devices 30 are actuated to lower the upper surface of the die table 34 to that of the outer lower plunger 48, the lower plungers 48, 50, 52 and rod 54 remaining stationary. The lower outer and intermediate plungers 48, 50 and rod 54 are then lowered simultaneously as inner lower plunger 52 is moved upward to the level of the die table surface 46 for removal of the moulding. The die table 24 is returned to starting position 35 where the lower intermediate and inner punches 50, 52 and core rod 54 are moved downward to their die filling position. Press disassembly.-The lower and upper gear-box assemblies 16, 14 are mounted on slideways in the machine frame whereby they may be removed for attention. The powered material compacting assembly comprising upper (264) (Fig. 12, not shown) and lower (262) platens and the intermediate die table (260) is mounted at the guide rods (242) to upper and lower pairs of rectangular section blocks (240 and 238). The upper pair of blocks (240) are each provided with upper surfaces inclined towards each end from the mid point thereof. The blocks are located in the press frame adjacent flat horizontal frame surfaces and are each looked in position by two wedges (256), Fig. 16 (not shown), which are forced into position between the horizontal press frame and adjacent inclined block surfaces by jacking screws (252) threaded into the ends of the block (240). Modified compacting assembly. Fig. 12 (not shown).-In a modified arrangement a single upper plunger (272) is employed and the die table (260) is attached to a pair of hydraulic cylinders (300) which are displaceable with respect to stationary piston (314) and rod (244) assemblies comprising the cushioning device. The upper platen (264) is provided with stop surfaces (280) which, on descent of the platen, engage adjustable stop surfaces (284) of the die table (260) whereby pressure is raised within the device to prevent continued descent of the platen and table. A downward extension (322) of each cushioning cylinder is provided with spaced radially extending stop lobes (326) which are rotatable into or out of alignment with registering stop lobes (328) fixed with respect to the machine, whereby the die table cushioning device may be rendered inoperative if desired. Moulding operation of modified assembly, Fig. 18.-For the filling operation, the core rod 350 is positioned level with the top of the die table 260, the lower punches 344, 346, 348 are positioned at their maximum depth and the upper punch 272 retracted. The upper punch 272 then enters the die cavity and core rod 350 is moved above the die table top surface. The lower plungers 344, 346 and 348 are then moved upwardly whilst the upper plunger 272 continues downward movement as the cushioning device permits lowering of the die table 260 until the stop surfaces (284) thereof engage the stop surfaces of the upper platen (264) when the compacting operation is completed. To eject the moulding, the upper plunger 272 is retracted, and the core rod 350 retracted level with the die table surface 337; the lower plungers 344, 346, 348 then move upwardly and maintaining alignment until the upper ends of plungers 344, 348 are level with the die table surface 337, permitting removal of the moulding. The die table 260 then returns to the filling position whereupon the lower plungers are retracted.