Patent GB-401434-A (GB)
Title: Improvements in and relating to valve control mechanism for liquid levels
IPC: D06F33/04
Filed: 1932-07-15
Abstract: 401,434. Ball - and - float valves. CRAWSHAW, C. B. H., 223, Meols Cop Road, Southport, Lancashire. July 15, 1932, Nos. 20003 and 30717. [Class 135.] A float-operated valve control mechanism, especially for use in laundry machines, of the kind which, by means of co-operating stops on a rising and falling member and on a rotatable cylinder which is re-set during the falling movement of the float, closes a fluid supply valve on the attainment of a pre-determined series of different levels of the fluid, is arranged to operate without relay means between the float and the valve. In the form shown in Figs. 1 and 2, vertically and laterally spaced pins 29 on a frame 30 which rises and falls with the float engage correspondingly laterally spaced pins 28 on a cylinder 22 rotatably mounted on a bracket 19 pivoted at 24. A spring 27 engages pins 23 on the cylinder 22 and acts as a ratchet allowing only anti-clockwise rotation of the cylinder. On the float rising to a predetermined level, one of the pins 29 engages the corresponding pin 28 on the cylinder 22 which, as it cannot rotate clockwise, is lifted and turns the bracket 19 about its pivot 24. A crank arm 26 engages the bracket and is thus turned, so causing a cam 17 to raise the arms 15, 16 of a toggle joint, which allows the valve supplying the liquid to close. When the liquid is run off the float sinks and a pivoted gravity pawl 34 at the top of the frame 30 engages one of the pins 23 and so rotates the cylinder 20 to bring another of the pins 28 into position to be engaged by the corresponding pin 29 when the float next rises, the liquid supply being thus cut off at a different level. In a modification, the cylinder 22 is mounted on a fixed bracket, and operates the valve trip gear through a ratchet device when turned by the upward movement of the float. Figs. 8 and 9 show another form of apparatus comprising a cylinder 40 secured at the top to a bush 42 having projecting arms 43 engaging in a stirrup (not shown) attached to the valve trip mechanism. The upper part 49 of the float rod 31 is squared and passes up through the cylinder and through a square hole in a bush 44 rotatably mounted in the bush 42, the top end of the rod carrying pivoted gravity pawls 56 engaging between teeth 55 on a cylindrical member secured in the bush 42. As the float rises, a stop 50 on the float rod engages one of a number of pins projecting internally at various heights in the cylinder 40, which is thus raised, so raising the stirrup from which it is suspended and actuating the trip gear to close the valve. On descent of the float, the gravity pawls 56 engage the inclined surfaces of two of the teeth 55 and, sliding down them, cause the rod 31 to rotate to the next operative position so that on ascending the stop 50 engages another pin 59. Spring-pressed balls 61 entering recesses 60 in the rotatable bush 44 through which the rod 49 passes maintain it in the adjusted angular position. In a modification, the cylinder 40 is attached to the float and is rotated on each downward movement by similar gravity pawl mechanism, the pawls being mounted on the lower end of the non-rotatable valve rod.