GB1518972A - Weighing machines - Google Patents

Abstract

1518972 Proportioning by weight R W CULLEY 7 Oct 1976 [16 July 1975] 29811/75 Heading G1W A machine for proportioning materials by weight prior to mixing thereof comprises a plurality of weighing units, each unit comprising a hopper 10 and a weighing container 4 movable between a filling position, a holding position and a discharge position, the container being carried by a counterbalanced member 1, overbalance of which under the weight of material in the container, releases the container for movement from the filling position to the holding position, the containers being releasable from the holding position only when all the containers are in the holding position. Each container 4 comprises a drum having four compartments 9, and rotatably mounted on lever 1 which is pivoted on a rod 12 and carries an adjustable counterweight 5. With the container empty, it is raised to an uppermost filling position shown in Fig. 1 by the counterweight. In this position its angular orientation is defined by a fixed bar 19 engaging two of the four studs 18 on the side of the drum, the orientation being such that the uppermost compartment 9 is asymmetrical with respect to the vertical so that material in the compartment tends to turn the container clockwise. Material flows from the hopper into the container until its weight is sufficient to pivot lever 1 into engagement with stop 13. This pivoting movement acts via a linkage 15 on a shutter 11 of hopper 10 to close the hopper outlet, and also disengages studs 18 from bar 19 so that the container rotates until one of four members 21 on the container engages a latch bar 22. In this position, shown in Fig. 2, one of four light tubes 25 coincides with the path of a light beam 28. The weighing units of the machine are aligned side by side, Fig. 4 (not shown), and when all the units have achieved the state shown in Fig. 2, light from source 26 passes through the light tubes 25 to a detector which acts via a solenoid to move the latch bar 22 which is common to all the units, out of the paths of members 21. The containers then simultaneously rotate to the discharge position and discharge into a common receptacle, Fig. 3 (not shown). When a container is empty, it is moved to the uppermost position, with the next compartment 9 in the filling position, by the action of counterweight 5. The shutters of the supply hoppers and the release of the drums from the holding position may be effected manually.