Patent GB-763466-A (GB)
Title: Improvements in or relating to an internal combustion engine
IPC: F01M13/02
Filed: 1953-12-22
Abstract: 763,466. Treating charge; ventilating crank chambers; regulating. GEFFROY, R. R. L. Dec. 22, 1953 [Dec. 24, 1952], No. 35628/53. Classes 7 (2) and 7 (6). A motor vehicle engine comprises air filtering means 14, Fig. 3, for the intake air and valve means R<SP>1</SP> which opens only when the vehicle drives the engine to connect the intake manifold 8 to atmosphere through the filter 14. A pipe 23 leads to a chamber 25 in the air filter 14 connected to the carburetter inlet 13, which filter is of the oil-bath type and causes a small substantially constant pressure drop in the air flowing therethrough. Under normal running conditions air enters the crankcase through an air filter 21 and orifice 22 on the oil filter tube 20 and the crankcase gases are drawn off through passage 23 to the carburetter inlet. When the throttle valve 10 is closed and the vehicle tends to drive the engine, the valve R<SP>1</SP> is opened and the crankcase gases are sucked through pipe 28 into the intake manifold. The valve R<SP>1</SP> may be actuated by the intake manifold suction, but in Fig. 3 it is actuated by an electromagnet 57 which is under the control of relay 76 which may be energized either by a switch P actuated by the accelerator pedal 83 or by a relay P which is included in the circuit of an automatic gear change system 61, 62. The switch I<SP>2</SP> is closed whenever the pedal 83 is depressed to open the throttle valve, whereby the relay 76 is energized and its contact member C breaks the circuit of the electromagnet 57 to keep the valve R<SP>1</SP> closed and closes the circuit of the ignition coil 70. The relay 66 is energized when the engine is idling or running below a predetermined low speed which also causes closing of the circuit of relay 76 to break the circuit of electromagnet 57, keeping the valve R<SP>1</SP> closed. When the engine is acting as a brake on the vehicle, the throttle valve 10 being closed, the switch I<SP>2</SP> is opened and the relay 66 is de-energized so that the circuit of relay 76 is broken and the contact C closes the circuit of the electromagnet 57 and the valve R<SP>1</SP> is opened, the circuit of the ignition coil 70 being simultaneously broken. The valve R<SP>1</SP> may be replaced by a valve R<SP>2</SP>, actuated by intake manifold suction under the control of a valve 95 which is actuated by an electromagnet 99 which replaces the electromagnet 57 of Fig. 3. In a further modification, Fig. 6, the whole of the air for the engine is drawn through the crankcase, the oil filter pipe 20a constituting the air inlet and the pipe 23a connecting the crankcase to the carburetter inlet having incorporated therein a cooler 102 for condensing oil vapour. A branch pipe 27a connecting the crankcase to the inlet manifold includes a valve R<SP>3</SP> similar to that of Fig. 5, the control valve of which is operated by three levers, connected respectively through links 107, 108, 109 to a manual gear change lever 104, the accelerator pedal 83 and the clutch pedal 105, so that the valve R<SP>3</SP> is kept closed under normal running and idling conditions and opened when the vehicle is driving the engine. An ignition cut-out switch may also be operated when the valve R<SP>3</SP> is opened.