Improvements in windscreen washers

949,036. Windscreen washers. TRICO-FOLBERTH Ltd. June 10, 1960 [June 11, 1959; April 12, 1960], Nos. 20057/59 and 13062/60. Heading A4F. [Also in Divisions F1 and F2] A windscreen washer system comprises a vacuum actuated diaphragm pump 4, Fig. 1 (see Division F1) mounted in a reservoir 2 and having a non-return valve 30 in a vacuum supply pipe 28 and/or a control valve 26 in a delivery pipe 22 together with a valve for admitting air to the pump vacuum chamber 6. The pump diaphragm 10 is moved on its suction stroke by vacuum, e.g. from an engine inlet manifold, and on its delivery stroke by a spring 12, on admission of air to chamber 6. The pump inlet valve has a projection engageable by the diaphragm towards the end of its delivery stroke to open the valve and produce an abrupt cut-off at nozzles 24. Admission of air to the vacuum source during delivery is restricted by a constriction 48 in pipe 28 or, alternatively, prevented by a control valve incorporated in valve assembly 26. In the embodiment of Fig. 2, valve assembly 26 comprises rubber tubes 34, 36 closable by plungers 40, 42 under the control of a rod 44 operable by hand, either directly as shown, or through a rack and pinion or solenoid. In the embodiment of Fig. 3, the valve assembly comprises a spring-loaded disc 62 forming the air admission valve, and a spring- loaded diaphragm 50 forming the delivery valve. Diaphragm 50 closes a pump pressure connection 52 at its centre and when moved leftwards by a knob 72 is held in its open position, together with disc 62, by the pump pressure in connection 52 until the pressure falls or knob 72 is moved rightwards.