Abstract: A thermostatic mixing valve is described having separate valves for hot and cold water each with a stepping motor to adjust their positions and connected to a microprocessor using a temperature sensor in a mixing chamber to read the mixed temperature and step the motors individually to adjust the valve positions as required.

Abstract: A mixing tap for a kitchen sink or like comprises a functional assembly of water ways in a body with control valves enclosed in a shroud for aesthetic considerations. The shroud is generally tubular with a second part and these two parts meet about an axis of the control valve normal to the axis of the spouts 22 so that a seamless smooth exterior can be provided on the spout.

Abstract: A water tap has a closure member in the form of a rubber or like cup 34 located in a chamber in carrier 32. The base of the cup extends across the port 28 which is to be closed when the tap is in "off" condition and the base of the cup has a hole 38 registered with the port in that off condition. Hence water can flow into the cup and the water pressure in the cup acts to hold the cup on the seat whereas pressure in the port acts against the base of the cup in the opposite direction but on a smaller area of cup. Hence the higher the water pressure the better the seal.

Abstract: A motorized valve, FIG. 2, is provided with a solenoid operated clutch which is energized when the valve is in operation and which can be de-energized, for example on power failure to allow the valve to be instantaneously driven to a closed position. The valve has a motor with a non-circular shaft driving the screw of a screw and nut mechanism in which the nut carries the valve closure element, and the clutch comprises a plurality of balls carried by a cage and held in engagement with the screw by a clutch ring which is held in the operative position by the solenoid. De-energization of the solenoid allows the ring to be spring-driven allowing the balls to disengage from the groove and allowing the screw to be displaced out of the cage by the driving spring.