GB503872A - Improvements in flow meters for liquids - Google Patents

Abstract

503,872. Flow - meters for liquids ; ratchet gearing. SERCK, H. O. Oct. 16, 1937, No. 28232. [Class 102 (i)] [Also in Group XXIV] A flow-meter for fuel or other liquid comprises a pump having a variable displacement, means to vary the said displacement in accordance with the pressure of liquid in the discharge line, and means to indicate and/or record the amount of liquid pumped. Fig. 1 shows a single piston 1 which is reciprocated from an eccentric 3 by a lever 2 having a fulcrum 4 which is movable by a spring-loaded control piston 6 sliding in a cylinder 6 under the action of the pressure of the liquid delivered by the pump against the action of a spring 6a. The reciprocatory movement of the piston 1 is converted into uni-directional rotation of an indicating hand 12 by means of a rack 7, a quadrant 8, friction and retaining pawls 9, 10 and a wheel 11. The momentary consumption may be measured by means of a Venturi instrument in the discharge line beyond the piston 5. Fig. 2 shows two pistons 15, 16 reciprocated within cylinders 13, 14 by a fixed-fulcrum lever 25, the crank-arm of which has its pin 24 slidably engaged in a slot in a reciprocating member 17 pivoted about a fulcrum pin 18 journalled in a spring-loaded bell-shaped control piston 19, liquid being dis. tributed to the cylinders by a rotary slide valve 21. Movement of the bell 19 may operate a pointer over a scale to indicate the flow of liquid per unit of time. The bell-shaped piston 19 may be replaced by a metal bellows. The alternate reciprocatory movements of the pistons 15, 16 may be converted into unidirectional rotation of a spindle 30, Fig. 6, carrying a counter, by connecting their upper ends with the free ends 35, 36 of two steel or inextensible ribbons 26, 27 passing round rollers 28, 29 on the spindle 30 and interconnected by a wire 33 passing round a roller 34, a spring 37 serving to maintain the ribbons taut. The counter may be combined with speedometer or dynamometer mechanism so as to indicate consumption per mile or per horsepower, and the indicating means may be combined with moving charts and styles for giving permanent records. Figs. 9-12 (not shown) illustrate the combination. of a pump such as that shown in Fig. 2 with converting means such as that shown in Fig. 6. Fig. 7 shows a modification in which each piston is connected to a rack 39 in engagement with a pinion ring 41 having elastic spokes 42 arranged at an angle on a hub 43, the shaft of which carries the counter. Fig. 14 shows a further modification comprising racks 68, 69 engaging pinions 70, 71 free on a spindle 75 which is connected to a coaxial hollow spindle 72 by means of a pin 76, the hollow spindle 72 carrying friction discs 78 and being moved longitudinally by a cam 73 and lever 74, each time the pistons reach their extreme positions, to couple the discs 78 with the pinions 70, 71.