GB200877A - Improvements relating to automatic weighing machines - Google Patents

Abstract

200,877. Garratt, C. F. March 22, 1922. Automatic-feed weighers. - In an automatic weighing-machine employing horizontally movable main and dribble feed valves, a vertical main shaft beneath the valves is provided at its upper end with means for opening and closing the main valve, and an automatic clutch is provided for engaging and disengaging the valve-operating shaft to and from a continuously rotating source of motion, means actuated from the dribble feed valve being provided for controlling the clutch and the discharge door of the weigh pan. An electric motor 3 drives a shaft 4 passing through the vertical valve-operating shaft p which is driven by the engagement of a toothed clutch member 5 on the shaft 4 with a pivoted catch 7 on the shaft p. Assuming the catch 7 to be in engagement with the clutch member 5, the shaft p rotates, and bv means of an arm q draws back the main valve h into the open position shown. The dribble feed valve l slides in guides beneath the main valve and is carried back when the main valve opens. The material from the hopper b runs freely into the weigh pan d until the continued rotation of the arm q moves the main valve again into the closed position. The size of the feed orifice j is adjustable to regulate the quantity of material thus delivered. At the end of the closing movement of the main valve the catch 7 comes in contact with a lever 8 and is thus liberated from the clutch member 5, and the shaft p is consequently arrested. Material flows through a dribble aperture k, the dribble valve l being retained by a catch t. When the weight has been made up the weigh beam c tips and closes the circuit of an electromagnet w which releases the catch t and allows the dribble valve to close under spring action. A projection 13 on the dribble valve rocks a lever 9 and (1) opens the discharge gate e of the weigh pan by means of a rod 14 and spring- controlled striker 16, (2) withdraws the lever 8 so as to allow the clutch parts 5, 7 to re-engage and again rotate the shaft p to commence another cycle of operations. The discharge gate e automatically closes under its counterweight. To prevent tilting of the beam as the main feed is delivered, a projection on the main feed gate engages an abutment on the rear of the beam. A stop 28 limits the return movement of the beam. Stirring devices. A uniform flow from the supply hopper is maintained by. a stirrer 18 driven by bevel wheels from the shaft 4. A change-speed gear 20 may be provided to vary the speed to suit different requirements. An additional stirrer 25 may be provided within the hopper.