GB871258A - Weight checking apparatus - Google Patents

Abstract

871,258. Sorting by weight. FOOD MACHINERY & CHEMICAL CORPORATION. June 16, 1958 [June 17, 1957], No. 19203/58. Class 143 A weight checking apparatus comprises means for continuously moving articles across a weighing platform resiliently preloaded to a position which is maintained for all articles below a predetermined weight and associated with a transducer producing different electric signals according to whether the platform is depressed from the initial position or not and an article segregating mechanism operated through actuating circuit means in accordance with one of the signals to effect segregation of articles of each of the weights. In the form shown, articles of oblong form are fed on to a flexible conveyer 31 on the machine, passing under a star wheel which ensures regular spacing, and are carried across a platform 32 supported by two. V- shaped frames 79, 80 converging on a plate 83 and by two springs 69 (only one shown) bearing on the underside of the platform and a further spring 68 bearing on the underside of the plate 83. A pillar 89 carried by the plate 83 is urged upward by a spiral spring 95, means being provided to vary the tension of the spring for adjusting the weight at which the platform will be depressed. The pillar 89 also carries a rigid support arm 161 on the opposite end of which is mounted the movable core of a transformer 34 having an oscillator in the primary circuit and two opposed secondary windings so that movement of the core due to downward movement of the platform produces an unbalance in the voltages induced in the secondary windings which is used to produce a current which may operate a recording instrument and may be read on a measuring instrument. It is however primarily used to bias the grid of one of a pair of thyratron tubes so that this is prevented from firing. The second tube is connected in the circuit of a photoelectric cell 38, Fig. 6, which is normally illuminated by a lamp 269, the rays of which are cut off by the interposition of an article on the conveyer, thereby putting the tube in a state to fire. The tubes are so arranged that neither will fire unless both are in a conductive state, and this occurs only during the passage of an article of insufficient weight to depress the platform. In that event, the circuit operates a solenoid 293 to move an arm 296 into the path of the article whereby it is turned through 90 degrees from the position in which its long axis is transverse to the direction of travel. As they leave the conveyer 31, the articles traverse two parallel sets of rollers 297, 298 spaced apart so that articles turned through 90 degrees will drop between these into a reject shoot 39.