GB727658A - Improvements in or relating to fuel pressure regulating device for fuel feeding system - Google Patents

Abstract

727,658. Regulating ; carburetting apparatus ; vaporizers. KROW, C. J. Oct. 24, 1951 [Oct. 25, 1950; June 26, 1951], No. 24841/51. Classes 7(3) and 7(6). A fuel pressure regulating device for a fuel feeding system comprises a casing having a chamber, a wall having its outer peripheral portion sealed in fluid tight relation to the casing to divide the chamber into a pair of chamber portions, a vent for one of the chamber portions, the wall having a flexible portion separating the chamber portions and movable in response to a difference in pressure in the chamber portions, a hollow fuel inlet member carried by and extending into the casing, sealing means for connecting the inlet member with the wall the inlet member having a valve port opening into the space between the sealing means and the wall, a port closing element carried by the wall and movable in response to flexing of the flexible portion to control fuel flow through the port, a fuel passageway through the wall connecting the valve port with the other chamber portion and a continuously open fuel outlet passageway leading out of the casing from the chamber portion. The device may be attached to conventional gasoline carburetters. In Fig. 1 an inlet 19 is connected to a high pressure liquid petroleum fuel tank. The fuel passes to a high pressure regulator 22 where its pressure is reduced to about 5-9 lbs./sq. in. (see also Fig. 2) and the fuel is vaporized by heat supplied by engine coolant admitted to a member 124. The vaporized fuel passes by way of a passage 121 controlled by a member 122 into a space 120 and from there to a space 61 and a heated outlet conduit 28 to a manifold block 30. From the manifold block two conduits lead to an induction passage 83. One 36 supplies fuel for idling to the downstream side of a throttle valve 38, the amount being controlled by a valve 40 and the other 32 supplies main fuel to the induction passage under control of a valve 34. The high pressure regulator comprises a valve 136 operated by an adjustably spring loaded diaphragm 144. The fuel passes to the passage 121 through a passage 142 controlled by a valve 164. An annular space 62 in a lower dish-shaped member 56 is vented to atmosphere. At starting a gasoline carburetter 2 may be used. When the engine has started a valve 10 is closed and a valve 42 is opened to initiate the supply of liquid petroleum. The engine coolant enters at 44 and passes to the member 124 and through spaces 66, 64 and through a jacket 74 of the hose 28 to return connection 46. Fig. 3 shows an embodiment in which a bellows 214 is employed. The inlet 230 is supplied from a regulator 22 or from a conduit supplying vaporous fuel at low pressure. An outlet 226 leads to a manifold block 30. The bellows 214 may be replaced by a cup-shaped diaphragm member and the diaphragm 204 may be urged downwardly by an adjustably loaded spring. In a modification a heating chamber is employed in association with a casing member such as the member 200. In another modification the idling conduit 36 passes directly to the chamber 222 and a flow restricting valve can be placed in this conduit. The idling fuel supply may be led to a fitting between the carburetter and the engine induction pipe a valve being provided in the fitting to control the flow of fuel. The fuel may be drawn either from the chamber 222 or from the manifold block. Fig. 7 shows another embodiment comprising bellows 424, 416 located in a casing 430 surrounded by a heating chamber 438. In a modification of this embodiment the inner bellows 416 is deleted and is replaced by a diaphragm which extends between the upper ends of the bellows 424 and the member 412. In Fig. 10 fuel enters a high pressure regulator 760 at 762 and leaves it at 764 on its way to an inlet 738 of a low pressure regulator comprising a diaphragm which operates a plate like member 746 which carries a valve seating member 750 which controls the flow of fuel through the low pressure regulator. An outlet 716 is connected to the conduit 76 (Fig. 2). The fuel on its way to the inlet 762 is heated in a coil 768 by engine coolant. The regulator 760 projects into the heating chamber 706. A plunger 758 permits manual control of the fuel. In Fig. 11 the fuel passes through a heater coil 852 heated by engine coolant to a valve 840 controlled by a diaphragm 844. From the valve it passes to an outlet 880 by way of a passage 824 and is controlled by a valve member 868 which co-operates with a seating 860. The valve member is controlled by a diaphragm 810. The outlet 880 serves to transmit the fuel to the conduit 28 for supply to the engine as described in Fig. 1. Engine coolant enters the chamber 802 by a connection 857 and leaves by an outlet 858 preferably passing to a further heating chamber 884. The fuel used may be propane or butane.