Patent GB-478129-A (GB)
Title: Improvements relating to liquid measuring and dispensing apparatus
IPC: G01F15/07
Filed: 1936-07-10
Abstract: 478,129. Valves. AVERY-HARDOLL, Ltd., and FRASER, J. July 10, 1936, Nos. 19118/36, 19120/36, and 6004/37. [Class 135] [Also in Group XVIII] An apparatus for dispensing measured quantities of liquid fuel &c., and having a flow meter, is provided with means under the direct control of the operator for reducing at will the rate of flow of the delivery to or below a predetermined amount and with means under the control of the indicating mechanism for automatically etfecting the cessation of delivery at certain predetermined positions of the indicating mechanism subsequent to the change in the rate of flow. Three embodiments of the invention are described. In the first embodiment, the liquid is delivered through the flow meter and the usual hose to the passage A, Fig. 1 of the nozzle valve, delivery commencing when a lever 26 is raised to depress a valve-stem 24 the head 23 of which, after a short downward movement against the resistance of a weak spring 23a depresses a plunger 28 urged by a strong spring 29 against a main flow valve 21. On the commencement of delivery, a cam disc 4 driven by the flow meter shaft 3 rocks a bell-crank 8a after the delivery of each unit, e.g. half gallon, this bell-crank making and breaking an electric circuit including a solenoid 11 which thus actuates a plunger 12 operating a counting mechanism 15 and also a rocking lever 16 governing a valve 17. During the delivery of the last unit of the required quantity, information as to which is furnished by the counter 15, the operator releases the lever 26 sufficiently to allow the valve 21 to close, further flow, of a dribble character, taking place through the port 18 past the valve 23 and through ports 28c in the plunger 28 until, at the completion of delivery of the final unit of the required quantity, the valve 17 closes the port 18 and cuts off delivery. An adjustable pawl 5 determines the position of the cam 4 when zeroizing. A gong operated by the counting mechanism may warn when delivery is to be effected by the automatic dribble control. In the second embodiment of the invention the delivery from the flow meter (not shown) is supplied to a passage 32, Fig. 3, provided with a piston valve 38 leading to a main delivery pipe 33 coupled to the main hose 34, and with a further valve 37 leading to a small pipe 35 which is coupled to a small hose 36 within the hose 34. The valve 37 has a stem 37a which is slidable within the stem of the piston valve 38 under the influence of a spring 42, within limits determined by a cross pin 41. The hose 34 opens into the passage A of the nozzle valve 55, the hose 36 opening into a separate passage controlled by a valve 56. The valves 55, 56 are governed by a bar 57 pivoted to a rod 58 controlled by the hand lever 61 and unequally loaded by springs 59, 60. On raising the lever 61 the valves 55, 56 are released and the pressure of the liquid raises the valve 38 and opens the valve 55 leading to the discharge nozzle. The raising of the valve 38 also results in the lifting of the valve 37 and this movement rocks, through linkage 43, 44 a boll-crank 45 whereby a catch 52 pivoted in a lever 47 and adjustably set relatively thereto by a screw 51, is advanced so as to be hold by a fixed stop 46a. During delivery of the final unit of the required quantity the operator releases the lever 71 sufficiently to close the valve 55 whereupon the valve 38 falls and closes the pipe 33. Dribble flow continues thereafter past the valves 37, 56 until at the completion of delivery of the final unit, a pin 48, on a disc 49 driven by the flow meter shaft, lifts the lever 47 and strips the catch 52 thereby allowing the valve 37 to close to cut off delivery. A gravity pawl 53 acts as a zeroizing stop for a pin 49a on the disc 49. In the third embodiment of the invention a hollow piston valve 65, Fig. 4, has a skirt portion 65a closing the pipe 63 from the flow meter, the valve having ports 65b closed by a lightly loaded valve 71, so that when pressure develops in the pipe 63, the valve 65 is depressed and the valve 71 lifted to allow delivery to take place through the ports 65b and the discharge pipe 64c. When the rate of flow is reduced by the operator partially closing the nozzle valve prior to the delivery of the final unit the difference of pressure in the pipes 63, 64c is diminished thereby allowing the valve 71 to close the ports 65b whereupon the piston valve 65 rises and seats on the base of the pipe 64c further flow continuing by way of an adjustably restricted passage 63a and port 69a through a pipe 67 and thence through ports 73c to the pipe 64c, a valve 63a being held slightly open during this dribble flow by a lever 78 governed by the meter shaft 87. At the first lifting of an arm 84 by a stop 88 on the meter disc 86 after the partial release of the nozzle valve lever to reduce the rate of flow, a stop 84a on the arm 83 is tripped from a catch 82b whereupon the arm 83 slides forward until arrested by the engagement of a stop 83a with the catch, this position corresponding to such a disposition of the lever 81, plunger 80 and arm 78 that the valve 73a is held slightly open to permit the dribble flow. Thereafter flow continues until a pin 85 on the meter disc 86 again actuates the arm 84, to trip the stop 83a and thus allow the valve 73a to close. The nozzle valve may be controlled by a lever 92, Fig. 5, pivoted on a hand lever 93 bearing on an abutment 94 so that the operator may feel when he moves the valve from a partially open position corresponding to dribble flow, to a fully open position.