GB519646A - Improvements in or relating to fuel pumps - Google Patents

Abstract

519,646. Fuel pumps. HANDELSAKTIEBOLAGET VIDAR. Sept. 26, 1938, No. 28046. Convention date, Sept. 28, 1937. [Class 102 (i)] [Also in Group XXVII] In a fuel pump for internal combustion engines in which fuel is separately delivered to different outlets from a common chamber at different times during each delivery stroke of the plunger or the like, and in which some of the engine cylinders are disconnected during low and/or idle running, the pump is provided with by-pass pipes which may be selectively opened to by-pass fuel from the pressure lines not required. In the form shown, fuel passes through a central inlet 8 into the pump chamber 23 and is delivered by plunger 3 through delivery ports 10aa, 10bb, passages 10a, 10b, spring-loaded valves 13a, 13b with compensating chambers 43, 44, to outlets 14a, 14b. There are four such deliveries, and at the same level as the four delivery ports are four relief ports 20a, 20b, 20c, 20d leading to a common overflow 30. The pump cylinder 2 is also provided with auxiliary overflow ports 20bb, 20dd communicating with a common auxiliary overflow passage 30c controlled by a plug valve 30d. When the latter is opened, two of the four engine cylinders will receive no fuel, independently of the rotational setting of the plunger 3 by a control rack. Fig. 6 shows the valve 30d controlled by a solenoid 71a which is energized when a throttle valve 72 in the engine air intake 73 is closed. by hand or automatically as by a governor. In one modification, a vacuum automatic control is provided, and in another the fuel is returned from the overflow passage to the suction line 8.