GB1242728A - Improvements in or relating to compacting machines - Google Patents

Abstract

1,242,728. Moulding powder. BIRMING- HAM SMALL ARMS CO. Ltd. 2 Jan., 1970 [13 Dec., 1968; 15 March, 1969], Nos. 59302/68 and 137.23/69. Heading B5A. A powder press comprises a vertically movable die 12 and opposed punches 2 and 11, the lower punch being carried on a part 10 of a frame 4, 5 which is moved -upwardly by reaction forces when the upper punch is driven downwardly; the upper punch is attached to a ram 1 movable in a cylinder 3 attached to the frame 4 vertically guided by rollers 7 on a fixed frame 6, The die structure 12, 13, 14, 24 is moved vertically relative the frame 4 and punch 11 by a piston and cylinder 17, 18, the piston terminating a column 24 of the die structure and the cylinder being attached to the part 5. A stop 15 limits upward movement of the die structure, and removable stops 16 and 19 its movement relative the lower punch. The frame 4, 5 is raised and lowered by an actuator 23, and a dashpot 22 provides a minimum and maximum resistance to the frame during its upward and downward movements respectively. In operation, after a product has been formed and removed from the die cavity by the upward movement of the lower punch and a transverse movement of a powder filling shoe across the face of the die, the lower punch is lowered by retraction of the actuator 23 and powder is drawn into the die cavity from the filling shoe; the die is lowered by operation of the piston and cylinder 17, 18 until it engages the stop 16 causing some powder to be returned to the shoe which then moves across the die surface to level the powder with that surface. A space is then provided above the powder surface by raising the die, and the stop 16 is replaced by stop 19. Compression of the powder is then effected by the punches and the die is moved down by the cylinder 18; the upper punch is raised followed by the raising of the die and lower punch which eventually ejects the compact.