GB978301A - Improvements in or relating to the automatic batching of bulk materials - Google Patents

Abstract

978,301. Automatic weight control. SCHWEIZERISCHE INDUSTRIE-GES. April 14, 1961 [April 20, 1960], No. 13436/61. Heading G3R. Equalisation of the differences in weight which occur in volumetric batching is effected by changing the volume of the batching chamber automatically whenever the weight of a predetermined number of filled containers exceeds, or drops below, a predetermined limit value. As shown, a container 7 is first filled from a hopper 1 by way of a batching chamber 2 the volume of which may be varied by a servomotor 3 and is then weighed on a machine 8 which supplies a voltage, representative of the weight of the container, to two analysing units 9 and 10. The unit 9 produces a signal when the container weight exceeds a certain upper limit, and the unit 10 produces a signal when the weight is below a certain lower limit. These signals are applied respectively to storage units 11 and 12 which each serve to actuate the servo-control 14 when a certain adjustable number of signals per unit of time is exceeded, whereby the servomotor 3 is started up to adjust.the volume of the batching chamber 2. A timing relay 13 determines the amount of the adjustment. Thus, units 11 and 12 may be adjusted to actuate the control 14 if, for example, ten or more of the filled containers are outside the upper or lower weight limit during a filling cycle of one hundred containers. If, say, eight containers are outside the limits, the servoarrangement does not respond. If, however, twelve containers out of the hundred are too heavy, the unit 11 actuates the control 14 so that the motor 3 acts to reduce the volume of chamber 2. If, on the other hand, more than ten containers are too light, then unit 12 actuates the servo-arrangement to increase the volume of the chamber 2. The units 11 and 12 may summate the signals qualitatively instead of quantitatively.