Patent GB-913662-A (GB)
Title: Improvements in hydraulic speed regulators
IPC: F02M59/32
Filed: 1959-03-02
Abstract: 913,662. Fuel injection pumps. BESSIERE. P. E. March 2, 1959 [March 1, 1958], No. 7183/59. Class 102(1). [Also in Group XXIX]. An hydraulic governor comprises a reciprocating positive displacement pump driven at a speed representing the regulating factor; as shown the pump is an engine-driven fuel-injector pump, having an inlet 17 fed from a transfer pump, not shown, and an outlet 18 to the cylinder 20 of an auxiliary reciprocating pump, the piston 21 of which is spring-loaded; the cylinder 20 has an outlet 22 to the fuel injectors, not shown. The cylinder spaces 20a, 20b on either side of the piston 21 are connected by a duct 26, the latter embodying a variable throttle 27 and a spring-opened shut-off valve 8a which is closed by the liquid pressure generated as the piston 15 ascends, With the valve 8a closed the piston 15 forces liquid through the outlet 18 to raise the piston 21 and causes fuel injection to take place: As the piston 21 uncovers an exhaust conduit 31, the surplus liquid is discharged into a conduit 1. When the piston 15 returns, the valve 8a is opened and the auxiliary piston 21 descends thereby forcing the liquid in space 20a through the duct 26 and throttle 27 into the space 20b ready for the next delivery duct. The length of the return movement of the auxiliary piston 21 is determined by the degree of restriction offered by the throttle, the quantity of liquid passing therethrough to the space 20b decreasing as the speed of the pump piston 15 increases. The conduit 1 opens to a chamber 2 containing an accumulator piston 9 loaded by an adjustable spring 10, the chamber 2 in turn leading to exhaust 3, the degree of opening of which, determined by an adjustable spring-loaded piston 12, ensures that the effective accumulator pressure is speed responsive. Conduit 1 also leads past a valve 8 integral with valve 8a to an adjustably spring-loaded member 4 connected to the throttle 27. When the conduit is supplied by the pump piston 15 the valve 8 is closed and the pump charges the accumulator but when the piston 21 again closes off the conduit 1, the valve 8 opens and the accumulator pressure both acts on the member 4 and piston 12, and a part of the accumulator liquid flows out of the exhaust 3, 4. As the speed of the pump 15 increases so the charging time of the accumulator increases and the pistons 4, 9, 12 move further to the right until they reach a steady position related to the new pump speed. The member 4 may operate the fuel injection pump rack, an electrical resistance or a valve, instead of the throttle 27. In a modification, Fig. 2 (not shown), the movable part of the throttle is formed on the member 4 and the accumulator is charged by the auxiliary piston 21. In another modification, Fig. 3 (not shown), an air cushion accumulator replaces the piston accumulator of the previous embodiments and the inlet 17 is supplied from another air cushion accumulator both of which later are successively charged by the piston of a transfer pump, which piston is cam actuated and integral with but of larger diameter than the pump piston 15. Specifications 837,087 and 885,297 are referred to.