GB292238A - Improvements in or relating to apparatus for the measurement of liquids - Google Patents

Abstract

292,238. Fraser, J., and British Petroleum Co., Ltd. March 15, 1927. Measuring devices.-A measuring chamber fitted with a piston communicates with a transparent chamber so that the delivery of liquid from the former is accompanied by a visible diminution of liquid in the latter. In the form shown, a rotary pump 7 operated by the crank handle 8 through bevel gear and lost motion or resilient connections is adapted in one direction of rotation to draw liquid from a cylinder 1 and pass it into a transparent chamber 10. A piston 6 is thereby raised and the cylinder is charged from storage through a pipe 2 fitted with a non-return valve 4. The chamber 10 is provided with an air vent valve 12 and with an overflow pipe 11 leading back to storage through pipes 14, 15. If the chamber 10 is not completely filled when the piston has reached its upper limit, continued pumping will draw liquid through a spring-loaded non-return valve 17 the head of which may also have a ball valve permitting escape of air from below the piston. The measuring chamber 1 having thus been filled as denoted by the level in chamber 10 the pump may be reversely driven so as to depress the piston and discharge the measured volume through a non-return valve 5 and a pipe 3. This valve 5 is preferably arranged so as to press heavily on its seating by means of toggle links 25 controlled by a spring 24, a direct-acting spring 26 also being provided if desired. To prevent communication between the suction and discharge pipes 2, 3, the latter pipe communicates with an upstanding annulus 21, a spring-controlled seating 22 on which is engaged by the piston in its lowest position to cut off communication. To relieve excess pressures in the apparatus a by-pass 36 fitted with non-return valves 38, 39 may be provided. In a modification the pump is of the reciprocating-piston type. Stroke, varying.-The upper limit of travel of the piston is determined by a stop 18 threaded into its support 31 and rotatable by a worm and spindle 34 to vary its height. To provide for delivery of a portion only of the standard volume a distance member loosely mounted on a thrust rod may be interposed between the piston and the stop. A similar result may be obtained by inserting a stop 29 in the path of the arm 30 forming a part of the gear for operating the counting or indicating mechanism from the rack and pinion 27, 28.