GB1295257A - - Google Patents

Abstract

1295257 Moulding helical gears ATELIERS R LAURENT SA 28 Nov 1969 [29 Nov 1968] 58352/69 Heading B5A In a press for moulding helical gears from metal powders between a pair of opposed helically toothed plungers 5 and 19 engaging within corresponding teeth of a die 18, the lower plunger 19, through which extends cores 11 and 13 to define an axial bore and bores parallel thereto, is fixed at a base 10 thereof, and via a carrier 14, to a fixed platen 15; the upper plunger 5 is mounted for rotation along a helical path relative to the die 18 during relative axial compressing movement therein; and the die 18 is mounted at a die casing 9 for rotation relative to the lower plunger 19, during relative axial displacement by abutment of rods 4, of the upper plunger assembly, with a platen 7 by which the die 18 is rotatably carried. The die 18 is rotated during axial movement relative to the plunger 19 by interengaging helical teeth 24, 25 of the carrier 14 and die casing 9, and the plunger 5 is rotated, during axial movement relative to the die 18, by its helically toothed engagement, at 21, 20, which an annulus 3 when this is upwardly displaced, by a corresponding amount, by abutment with the die casing 9 at dependent annulus sleeves within which slidably locate guide rods 6 connecting the casing 9 and annulus 3 for rotation together. The platen 7 is connected by rods 8, extending through the fixed platen 15, to a platen 16 which fixedly carries the cores 13 so that their upper edges are constantly spaced by less than 1 mm., e.g. 0À2 mm., from the face of the plunger 5 throughout the pressing movement thereof. The core 11 is independently displaceable through the platen 16, 15 and 17, to locate within a bore of the plunger 5. The platen 7 is moved downwardly against thrust rods 12 which pass through the fixed platen 15 and are mounted to a platen 17 which is vertically reciprocable to raise the platen 7 to its initial position.