Patent GB-782728-A (GB)
IPC: G01F11/28
Abstract: 782,728. Coin-freed liquid-measuring apparatus. AKTIEBOLAGET LJUNGMANS VERKSTADER. Dec. 6, 1955 [Dec. 7, 1954], No. 35013/55. Classes 27 and 106(5) A coin-freed apparatus for delivering measured quantities of fluid such as petrol has a measuring chamber 1 of adjustable volume 'filled by a pump, a rotary valve 7 which is released by insertion of a coin so that it can be moved from an initial position in which the inlet 6 from the pump is closed and the delivery outlet 29 is open to a second position in which the inlet is open and the outlet closed and means controlled by the pump pressure prevailing in the measuring chamber when filled for restoring the valve to its initial position Delivering liquids. When the valve shaft 9 is rotated from its initial position by a handle 13, a cam disc 15 on the shaft opens a valve 14 and compressed air is supplied above a piston to drive down a pump piston so that petrol is displaced from a cylinder in a tank below the measuring apparatus. The petrol passes through the valve 7 and a stack pipe 8 and, when the chamber is almost filled, it closes a float valve 18, thus leaving only two grooves 19 hy which petrol can pass to a small chamber 90. Above the chamber 90 is mounted a glass bell 20 having an adjustable float 21 which closes a valve 22 when the. petrol reaches a predetermined level in the bell 20. The chamber 90 is connected to a housing 24, Fig. 5, having a diaphragm 25 which reacts to the rise in pressure and releases a pawl 28 from the cam disc 15, thus allowing a pring 52 to return the valve 7 to the delivery position. The quantity delivered is varied by a displacer 2 which surrounds the stack pipe 8 forming both the inlet and outlet of the measuring chamber and is fixed to a spindle 3 having a pin 4 engaging a helical surface 5 so that rotation of the spindle by a wheel 32 raises or lowers the displacer in relation to the mouth of the stack pipe. In a modification, the surface of a displacer 64, Fig. 12, is shaped to a curve which allows for the correct variation in measured volume with variation in price, e.g. so that, for a change in price per litre from 56 tn 57 price units, the variation is 31.4 c.c. but, for a change from 84 to 85 price units, the variation is only 14 c.c. The displacer is splined to the stack pipe 8 and screwed to a spindle 65 which is rotated by a knob 67. Gearing 66 drives a sleeve 70 carrying a graduated price disc 31 which is rotated one step for each revolution of the spindle. Coin action. A coin falling down a shoot 10 comes to rest between a release disc 30 and a pin 61 on a pawl 12 and, on rotation of the handle 13 and therefore of the disc 30 from initial position, raises the pawl 12 clear of a partlytoothed ratchet wheel 49. When the handle reaches the delivery position, the pawl 28 engages the cam disc 15 to hold the valve 7 in delivery position and the handle and ratchet wheel are rotated back to initial position by a spring 54. A pawl 48 ensures that the handle is rotated fully to either of its two positions. The ratchet wheel drives the cam disc through a tappet 57 and the shaft 9 drives the valve 7 through a driving disc 33 and a tappet 51 projecting into a groove 62, the length of which determines the angle of rotation of the valve. A pin 59 on the cam disc prevents another inserted coin from passing through the apparatus during the delivery operation