GB1257891A - - Google Patents

Abstract

1,257,891. Compression moulding apparatus. COMMISSARIAT A L'ENERGIE ATOMIQUE and SOC. DE FABRICATION D'ELEMENTS CATALYTIQUES. 23 April, 1970 [30 April, 1969], No. 19435/70. Heading B5A. [Also in Divisions G1 and G6] A weighing machine automatically supplying contant weight batches of power to the die of a press comprises a spoon 44 carried by a flexible arm 42 having a strain gauge 62 mounted thereon and includes means for pouring the powder into the spoon, stopping the flow when the required weight is obtained, inverting the spoon to discharge its contents, and returning the apparatus to its original state in readiness for a repeated cycle. The flexible arm 42 is preferably carried by a sleeve 34 coupled with a jack 13 system for translational movement, the rotational movement required for the tipping of the spoon being effected by a skew groove 38 in the cylinder 40 along which the sleeve 34 is guided by a guidepin 36. A pin 46 mounted in the head 26 and guided parallel to the axis of the jack 13 by a bore formed in the stirrup piece 24 carries a funnel 52 by means of an electromagnetic vibrating mechanism 54. In operation, powder flows from a hopper (76), actuated by a vibrating distributer (74), into the spoon 44 until the predetermined weight is attained (which may be registered on a recorder (70)) when the strain gauge trips a relay which causes the distributer to stop and the jack to initiate forward movement of the head 26 and hence the spoon 44 and funnel 52. During this forward movement the punches (82), (84) move to extract the pellet previously formed in the die. When the sleeve 34 reaches the position at the start of the skew groove 38, the pin 46 carrying the funnel 52 is restrained by a stop 60 acting on the boss 58 hence over the period of pivotal movement of the spoon the funnel remains fixed in position over the die-hole. The powder is deposited and the switch 30 is closed by the lug 28 which initiates the return of the jack, and hence the spoon and funnel to their original positions. At this stage the punch (82) descends to compress the powder in the die. The device may be used for forming pellets of uranium oxide or mixed uranium and plutonium oxide. The weights specified may be maintained with a degree of precision higher than 1% and a rate of production of seven pellets a minute.