GB841202A - Improvements in internal combustion engine fuel injection systems - Google Patents

Abstract

841,202. Fuel ignition systems. BESSIERE, P. E. Oct. 8, 1956 [Oct. 13, 1955; Nov. 24, 1955; Jan. 20, 1956], No. 30635/56. Classes 7(3) and 7(6). [Also in Group XXVIII] A fluid-pressure operated member in a fuel injection system, e.g. a cylinder pressureoperated piston 2, Fig. 1, integral with a pump piston 3 feeding fuel to an injector 11, is loaded against operation by the fluid pressure by an electromagnet. In Fig. 1 an electromagnet 12 is energized to hold an armature 13 in contact with its polepieces, which armature acts through distance pieces 15 on the piston 2 to prevent movement thereof until the cylinder pressure acting on piston 2 is sufficient to overcome the pull of the magnet whereupon pistons 2 and 3 move upwards rapidly and injection takes place, the amount of fuel injected being controlled by an adjustable stop 6 controlling the travel of the piston 3. The time of injection is controlled by adjusting the current through the electromagnet 12 by a rheostat 17 controlled manually or by a centrifugal governor. Alternatively the electromagnet may be de-energized at the moment when injection is to take place, the circuit containing a rotary engine driven switch which is adjustable to vary the time of injection. In Fig. 4 a fuel injection valve 106 is resiliently connected through a spring 127 to an armature 129 attracted by an electromagnet 130, the valve 106 seating at 107 in a nozzle 105 carried by a piston 102 actuated by cylinder pressure and forming with a stationary plunger 111 an injection pump having a pressure space 113 supplied with fuel from an inlet 114 through passages 118, 117 and 119, excess fuel escaping from the pressure space through a passage 122 and being sucked out of space 103 by a suction pump through passage 123. At the start of compression the electromagnet 130 is energized to cause armature 129 to hold the valve 106 to its seat. The piston 102 lifts slightly under pressure until the ports 119, 121 are closed but further movement is then prevented by the fuel trapped in space 113 until electromagnet 130 is de-energized, which permits valve 106 to rise from its seat, the piston 102 then completing its stroke and forcing the fuel from space 113 through the orifice 108. Passages 132 in the armature 129 prevent damping of the motion thereof by air trapped underneath and fuel leaking past the valve 106 escapes through a passage 138. In Fig. 5 the upward movement of an injection pump piston 203 actuated by cylinder pressure is opposed by electromagnet 234 and a by-pass valve 237 serving to determine the end of injection by releasing the pressure in the pump pressure space 209 is held closed and opened respectively by electromagnets 220a, 240, the electromagnets 234, 220a, and 240 being energized under the control of rotary enginedriven switches. In Fig. 7 an electromagnet 335 holding a by-pass valve 334, connected to the pressure supply pipe 311a of an injector 312, closed is de-energized to permit valve 334 to open and terminate injection.