GB935011A - Improvements in batch weighing machines - Google Patents

Abstract

935,011. Automatic feed weighers. EASTERN GAS BOARD. Jan. 5, 1960 [Nov. 6, 1958], No. 35688/58. Class 143. A coke weigher, in which the feed to a weigh hopper 10 is by an inclined shoot 2 vibrated by a motor 3 and closable at its lower end by an upwardly swing- ing gate 18, is so controlled that the feed automatically stops when a predetermined weight has been dispensed and cannot be restarted until this load has been discharged and the weigh hopper's discharge gate 12 reclosed. Preferably the base of the shoot 2 is perforated so that undersize coke will pass into a reject hopper 6. Gate 18 is opened by a solenoid-operated fluid pressure ram 25 and closed by a counter-weight 22, but may be latched open by means contained in holding unit 32. This means comprises a lever 39 pivoted at one end to the arms 33 which support the gate and having at the other end a depression 40, Fig. 3, which is engaged by the free end of a pivoted lever 41 when the gate 18 is fully open. Discharge gate 12 is fully controlled by a ram 34. The whole apparatus is controlled by electrical relays (Fig. 5, not shown) whereby the following sequence of operations is ensured. Provided the hopper 10 is unloaded and its gate 12 closed, actuation of a push-button switch starts motor 3 and operates ram 25 to open the gate. When the gate is fully open the movement of lever 41, Fig. 3, into its latching position causes a cam 48 on this lever to act on a microswitch 49 and de-energize the solenoid of ram 25, which returns to its initial position. When the hopper 10 is nearly fully charged, a contact in the weigher 13 energizes a solenoid 43, Fig. 3, by which pivoted lever 41 is released from its engagement with arm 39, so that the feed gate closes. This closure takes place against the resistance of a dashpot 29, Fig. 2 (not shown), and the operation is adjusted so that final closure of the gate occurs when the precise required load has been fed. A switch operated by the closing gate also stops motor 3. A foot switch 38, Fig. 1, will discharge the load by opening gate 12, but is effective only if feed gate 18 has completely closed. Reclosure of discharge gate 12 may be made to effect automatic restarting of the feed.