Patent GB-516241-A (GB)
Title: Improvements in automatic control mechanism for the supply and discharge of liquids
IPC: G05D9/12
Filed: 1938-06-22
Abstract: 516,241. Automatically controlled valves ; washing-machines. AUTOMATIC CONTROLS, Ltd., and CURRIE, J. A. June 22, 1938, No. 18559. [Class 135] [Also in Group VIII] - ' In automatic mechanism for controlling the supply of liquids to a washing-machine or other container comprising supply-valves controlled by a rotary cam - drum or like member driven through a coupling which is released by means of a ram when a supply-valve is opened, and is re-engaged when the liquid reaches the desired level, an electrical liquid-level device controls an electromagnetic valve for releasing the pressure in the ram to allow ie-engagement of the coupling. The mechanism ensures that the liquid reaches the desired level independently of changes of pressure in the supply. The washing- machine. a shown in the figure is associated with a rotary cam-drum b controlling relay-valves, such as described in Specification 264,396 for permitting fluid to flow through pipes c' 'to the operating-cylinders d' of hot and cold water supply-valves d and of other valves referred to below. The cam-drum is driven through a friction-coupling b<2> which is disengaged by means of a wedge, fork or the like operated by a ram g communicating through a pipe c<3> with a cylinder h which contains a shuttle-piston h' and communicates with the operating-cylinders d'. The pipe c<3> is in communication with a valve i operated by an electromagnet i'. The washing-machine communicates through a pipe a' with a liquid-level regulating device j, such as is described in Specification 502,378, comprising electrodes j<1> of graded lengths provided with contact-studs co-operating with a rotary contactarm k<1> in circuit with the electromagnet i'. When the cam-drum permits fluid to flow to either of the operating-cylinders d<1>, the associated supplyvalve d is opened, the ram g releases the coupling b<2>, the cam-drum is stopped, and hot or cold water flows into the washing-machine. When the water reaches the desired level, the selected electrode j' completes the circuit of the electromagnet i<1>, the valve i opens, the coupling is reengaged, the cam-drum is re-started, and the supply-valve closes. When a mixture of hot and cold water is required, the control-drum is arranged to open both supply-valves d. The switch-arm k' may be set manually, but is preferably set automatically by a ratchet-device m<1> operated by a ram n which is connected to the operating-cylinder e<1> of the discharge-valve e of the machine. Alternatively, the ram is connected to a relay-valve actuated by the camdrum. Solutions of soap, blue &c. are delivered in measured quantities from tanks o ...r having supply-valves o<1> ... r' and discharge-valves o<2> .. r<2> operated by cylinders s under control of relay-valves operated by the cam-drum. The cylinders s of the valves o' ... r<1>are connected to valves t which are actuated by electromagnets under control, in the above-described manner, of liquid-level regulating devices u, some of these being automatically set by means of ratchetdevices v operated by rams in connection with the ram n. A valve f, operated automatically or manually, for flushing the machine is connected to an injector w for flushing the regulating- device j. Steam is admitted to the machine through an automatic valve x. The cam-drum may be axiaLly movable to select either of two sets of cams thereon. Specification 332,426, [Class 135], also is referred to.