Patent GB-746090-A (GB)
Title: Improvements in or relating to fuel supply apparatus for internal combustion engines
IPC: F02M63/00
Filed: 1954-01-15
Abstract: 746,090. Fuel injectors, regulating. CUMMINS ENGINE CO., Inc. Jan. 15, 1954 [Feb. 25, 1953], No. 1231/54. Classes 7(3) and 7(6) [Also in Group XXVI] A fuel injector is provided with a fuel supply passage 131, Fig. 11, which supplies fuel through an orifice 144 to an injection space 141 for injection by a plunger 145 and excess fuel flows, through a return passage 150, 155 containing a restriction 151. In a multicylinder engine the supply passage 131 is connected to a common supply line 42, Fig. 5, fed from a tank 10 by a gear pump 12 through a filter 15, pressure control valve 16, manual control valve 22, and governor operated valve 32. The valve 16 comprises a spring- loaded sleeve which is actuated by the fuel delivery pressure from the pump 12 to maintain a predetermined variation of pressure with engine speed. The manual control valve 22 comprises a rotatable plug with a passage 23 therethrough having one end always in communication with the passage 21 and the other end registering with the end of the passage 24 during normal running to control the flow therethrough but passing out of register therewith at idling, the fuel then being supplied through passages 25, 26 and 27. The passages 24, 27 lead to openings 35, 34 controlled by the valve 32. Figs. 3 and 5, which is actuated by a centrifugal governor 91 carried by a cage 93 rotated from the shaft 57 driving the gear pump 12. The governor is loaded by an idling spring 112, Fig. 3, and a maximum speed spring 110. At idling a shoulder 40 on the valve 32 cooperates with the passage 34 to prevent the idling speed exceeding a, predetermined value and at normal running the passage 34 is closed by the valve 32, the fuel then passing through the opening 35 to the fuel delivery port 36 connected to the delivery pipe 42. If the speed exceeds a predetermined maximum the spring 110 yields to permit the valve 32 to move to the right to close the passage 35 and open the delivery passage 36 to a drain passage 46, whereby the fuel supply is cut off and the pressure in, the delivery pipe 42 and injectors relieved through the drain 46 which leads into the interior of the body 51, Fig. 3, containing the pump 12, pressure regulating valve 16, manual valve 23 and governor-operated valve 32. The fuel drained into the body 51 passes out through a passage to the return pipe 44. The supply passage 131, Fig. 11, in each injector leads to an annular chamber 134 from which the fuel flows into the injector space 141 when an orifice 144 is uncovered by a mechanically actuated plunger 145 which on its downstroke forces the fuel from the space 141 through spraying orifices 153. The chamber 134 is connected to the return passage 150 from which the fuel flows through the orifice 151, an annular space in the plunger 145 and a port 153 to the upper port 155 of the return passage which is connected to the return pipe 44. The port 153 is normally closed by a collar 157 on the plunger and is opened shortly before the orifice 144 is opened, whereby fuel is circulated through the chamber 134 and the return pipe to remove any air from the chamber 134 before the orifice 144 is opened. In a modification, the plunger controls a port in the supply passage 131 instead of in the return passage.