GB931047A - Apparatus for the measured delivery of liquid - Google Patents

Abstract

931,047. Filling tanks. AVERY-HARDOLL Ltd. Nov. 21, 1961 [June 9, 1961], No. 41624/61. Class 21. [Also in Group XXIX] In a receptacle filling device a main valve is closed automatically to stop the flow of liquid into a receptacle when it reaches a desired level, the valve being held open by the action, on a piston associated with it, of liquid pressure derived at least in part from a jet of liquid, constituting part of the liquid flowing through the device, and directed on to a pitot tube the bore of which is connected to a chamber in which the piston is mounted, the jet being disturbed when the liquid reaches the desired level in the receptacle to reduce the pressure produced in the pitot tube and to allow the main valve to close. The device includes a first auxiliary valve opened to admit liquid under pressure from the upstream side of the main valve to the piston chamber, and a second auxiliary valve opened to permit the flow of fluid forming the jet, wherein the valves are caused to open successively by operation of a single control lever and the first auxiliary valve is closed automatically during the period starting with the formation of the jet of liquid and terminating with the opening of the main valve. Operation of the control lever 4a rotates a lever 6 against the action of a spring 5 thus rotating a second lever 8 to open the first auxiliary valve 10 to allow liquid under pressure to pass down a duct 21 to act on the rear face of a valve member 23 pushing it into abutting relationship with a face 19a of the piston 19 against the action of a spring 24 and then forwarding the piston slightly to the right as shown in Fig. 2. This opens ducts 2b to allow liquid to enter a nozzle 12 and spurt as a jet on to the pitot tube 18. The pressure in the pitot tube builds up and forces the valve member 23 away from the flange 19a and further forces the piston 19 and valve member 2 to the right to open the main valve. As the main valve begins to open the valve member 10 escapes from the lever 8 and closes under the action of a spring 11, the valve member 2 continues moving to the right under the action of the pressure built up in the pitot tube. The extent to which the valve opens is determined by the position in which the lever 4a is held and thus the position of the lever 8. The jet causes air to be drawn up a pipe 16 connecting a port 1c to a vacuum tapping. The flow of liquid continues until the level of liquid in the receptacle to be filled has reached the port 1c. Liquid is then drawn up the pipe 16 and fills the cavity 13 thus reducing the pressure in the pitot tube. This reduces the pressure on the left hand face of the piston 19 and allows the valve member 2 to move to the left to close the main valve under the action of a spring 31 and the flow of liquid through the nozzle. Specifications 724,064 and 727,639 are referred to.