GB461826A - Improvements in or relating to machines for making tablets - Google Patents

Abstract

461,826. Moulding tablets in rotarymould-table machines. STOKES MACHINE CO., F. J., WESTIN, C. J., and DONAGHY, A. Sept. 30, 1935, No. 26996. [Class 87 (ii)] In a rotary tablet-compressing machine which has a stationary table 13, Fig. 4, and a rotating head 15 with flanges at various levels in which vertically disposed pairs of punches 20, 21 are disposed to co-operate with corresponding moulds 22 in a mould table 30 of the head 15, a stationary grid 27 being mounted above the mould table 30 for feeding powder to be compressed into the moulds 22, a suction nozzle or nozzles 84, 85 are provided for removing dust on or about said flanges: In the construction shown, the head 15 is mounted on a spindle 14 and is rotated by a worm engaging a worm wheel 16 on the head. The upper and lower punches 20, 21 of each pair co-operate with moulds 22 through a stationary upper cam track 23, Fig. 2, and compressing roller 25 and a lower track 24 and roller 26. In the cycle of operations, the punch 21 on leaving cam 24 is lowered to open the mould and the powder fills in, the punch rising again on meeting a weight-adjusting cam 40 which removes excess of powder, next both punches strike rollers 25, 26 and the powder is compressed to a tablet, the tablet is then raised out of the mould and leaves by a discharge shoot 37. The feeding grid 27 receives powder from a hopper 29, and is subdivided by walls 127, Fig. 3, having staggered apertures 128, the material being moved back and forth over the moulds above which a surplus is always maintained, the surplus in the mould and excess powder placed in the grid being removed by a scraper 129 attached to the grid and pressed on to the mould table by a spring 130. The grid 27 is supported slightly above table 30 by adjustable bolts 32, the space between being varied according to the nature of the material being compressed. To enable the grid 27 to be readily adjusted and removed, each bolt 32 screws into a cap 25 which is externally threaded to screw into a support 36 on fixed table 13. Thread 32<a> on bolt 32 is of the same or finer pitch than, and is cut the same hand as the thread 35a on the exterior of cap 35. The bolt 32 is secured in a lug 33 on the grid by a lock-nut 34. This supporting means enables the grid to be removed from position and replaced without altering its adjusted position relatively to the moulds. Dust from table 30 and from a flange 81a of the bearing 81 for the lower punches, which underlies and is less in diameter than table 30, falls on an inclined portion 82 of a housing surrounding the machine, and is removed. Specification 461,854 is referred to.