Patent GB-569485-A (GB)
Title: Automatic control of cyclically-operated machines
IPC: D06F33/04
Filed: 1943-08-21
Abstract: 569,485. Valves for controlling cyclicallyoperated machines. WATSON, LAIDLAW, & CO., Ltd., and INGLES, W. L. B. Aug. 21, 1943, Nos. 13675 and 17963. [Class 135] [Also in Group II] The invention deals with the automatic control of cyclically - operated machines performing a successive series of operations in predetermined sequence using compressed air or other fluid acting on plungers, the sequence being controlled by adjustable cams on a cam-shaft which open valves a ... e in sequence. The invention is described in connection with a centrifugal machine or machines, for the treatment of sugar or other crystalline substances, but may be applied to washing machines. In Fig. 1, 1 indicates a driving motor for the centrifugal basket, 2 an exciter, 3 a ventilating fan, 4 a compressed air supply pipe and 5 an air exhaust pipe. The valve a controls the air supply to plungers 12 and 13 which operate a sugar plough 11 in the basket, an automatic byepass valve 14 being included in the circuit. The valve a also controls the plunger 15, to raise or lower the basket spindle. The valve b controls a panel 16 on which 17 is a button to operate the basket charging, 18 a full speed button and 19 a stop button. Valves c, d, e control plungers operating classifying, steaming and water washing apparatus, the plungers being numbered 21, 22, 23 respectively. The cam-shaft 37, Fig. 5, is driven by a motor 6 through a clutch controlled by a plunger 8. An independent valve 24, interlocked with the button 18, may be used to control charging of the basket. A stop valve 25, is closed to prevent a second charge from entering the basket, after the latter has been stopped and re-set. A plunger 26 is used to operate a brake, 27 is a magnetic valve, normally closed, but opened when the electric supply to the motor 1 fails, to allow a fluid supply to the plunger 26 and a clutch plunger 8. The brake may be operated by hand through a valve 28. Fig. 27 shows the piping and plunger arrangement to move the plough 11 and bottom bearing 15. When the latter is raised, fluid flows into the cylinder 13 to cause the plough blade to engage in the sugar wall in the basket 47. The fluid then flows to the cylinder 12 to force the plough 11 downwards, whereupon the blade removes the sugar from the wall of the basket. The fluid flow is then reversed and a valve 14 opened to allow exhaust fluid to escape. To start up the plant, the fan 3, air compressor and the cycle control motor 6 are first put into motion. The switch 17 is operated to bring the basket up to charging speed, 300 r.p.m., the valve 24 opened and then closed when the basket is full. The button 18 (full speed) is then pressed and locked in position by bringing the valve handle 24 to neutral position, and when a cam f opens the air valve, the basket is brought up to full speed (1600 r.p.m.) and the cam-shaft automatically controls the further operation by valves a ... e. An emergency brake 28 is operated to stop a machine; this automatically stops the motor 1, and the controls are returned to zero by means of an air byepass acting with the plunger 26. A magnetic valve 27 opens if an electrical defect develops before -the basket has reached full speed and allows air to pass to the plungers 26 and 8 and bring the controls to zero. Steam may be directed to the outside of the basket. When applied to a washing machine or machines, the cams may control the admission and outflow of hot or cold water, the admission of soap, bleach or steam, and other operations.