GB382429A - Improvements relating to weighing machines - Google Patents

Abstract

382,429. Automatic-feed weighers. SIMON, Ltd., H. and BRIAN, J. C., Bird Hall Lane, Cheadle Heath, near Manchester. Oct. 29, 1931, No. 29986. [Class 143.] Relates to an automatic weighing machine, such as a grain weigher, of the kind wherein a counterbalancing device assists the movement of the steelyard or equivalent part of the weighing mechanism prior to the dribble feed, and a compensating device is employed to compensate for the falling material at final cut-off. The invention consists in the provision of means which bring the counterbalancing and compensating devices into operation successively and which withdraw the counterbalancing device from the steelvard to enable the latter to return to its initial position before the compensating device comes into operation. In effecting a weighing operation the mechanism is first set in the position shown in Figs. 2 and 4 by raising a handle 17, Fig. 4, the movement admitting compressed air from a valve fitting 32 to open the main valve c, Fig. 1, of the feed hopper a. When the major portion of the charge has entered the weigh hopper b the steelyard e, assisted by the counterbalancing lever f, Fig. 2, rises, displaces a trip lever j, and allows an arm o to fall into the position shown in Fig. '3, a roller q displacing the counter-' balancing lever f clear of the steelyard e, and a lever s freeing the compensating lever g so that it may exert an upward pressure on the steelyard to compensate for the falling grain at final cut-off. In addition, the falling arm o acting through the spindle p causes the parts shown in Fig. 4 to be turned to the position shown in Fig. 5, thus operating the valve in the fitting 32 to admit compressed air to the cylinder 33, Fig. 1, and close the main valve c. During the closing movement, a member on the main valve, operating through a link and catch mechanism opens the dribble feed valve d, which is then held open by a catch. When the requisite quantity of grain has entered the weigh pan, the steelyard e moves upwards and disengages a catch lever z, Fig. 3, from a weighted lever 2 which then falls upon a member 5a and causes an arm 8 to fall and operate a valve 11. Compressed air passes to a cylinder 41, Fig. 1, and liberates the dribble feed valve d to cut off the feed. A part 9 on the falling lever 8 displaces the compensating lever g to leave the steelyard free and allow the operator to check the accuracy of the weighing. The fall of the arm 8 at the completion of the weighing also displaces a lever 45, Figs. 4 and 5, and permits the operator to raise a handle 44 in order to discharge the contents of the weigh hopper by opening an air valve on the spindle 37.