Patent GB-944312-A (GB)
Title: Improvements in a starting system for free-piston internal combustion engines
IPC: F02B71/02
Filed: 1961-07-24
Abstract: 944,312. Starting free piston engines. SOC. CIVILE POUR L'ETUDE D'ENGINS A PISTONS LIBRES E. P. L. July 24, 1961 [Aug. 9, 1960], No. 26661/61. Headings F1K and F1Q. A device for bringing the pistons of an engine with free pistons connected to compressor pistons into the starting position comprises a supply pipe for allowing compressed air to be passed to at least one of the compressor pistons in order to return it to its starting position, a control valve, and a starting valve actuable by a cam mechanism operatively connected to the compressor pistons, the arrangement being such that when the control valve is opened compressed air is admitted by the starting valve to the compressor cylinder until the compressor piston therein reaches its starting position whereupon the cam causes interruption of the admission of compressed air. As shown compressed air arrives from a compressed air source (not shown) through a pipe 18 as far as a control valve 19. In position I of the valve (Fig. 3) the air passes through a pipe 20 to a controlled (admission) valve 21 and forces down an inner movable component thereof 22 against the action of a spring 23 which component brings a roller 24 into contact with a cam 26. Under the action of the cam 26 and the roller 24 the rod 25 pushes the valve head 29 upwards against the action of a spring 31 thus opening a seating 32. Thus free passage is given to the air entering the pipe 20 and this air passes into a pipe 35. From the slide valve 36 a pipe 37 conducts air to the inner face of the control piston 38 of an inlet valve and opens it allowing compressed air to enter the space 15. The same pipe 37 also carries air to the closing piston 40 of the valve 17 thus preventing escape of air from the space 15. The same pipe 37 also carries air to the outer face of the control piston 41 of a discharge valve 42 and also holds it closed. Finally, the same pipe 37 also carries air to the inner face of the control piston 43 of a valve 44 and opens this valve. The compressor piston 3 actuating the motor piston 1 moves outwards under the pressure of the air in the space 15. When the pistons reach their starting position the face 50 of the cam 26 enables the rod 25 to descend and the valve 29 closes the air passage to the pipe 35. The rod continues to descend and the pipe 35 is connected to atmosphere through a passage 30. The slide 36 moves towards the right under the force of the compressed air and the pipe 37 iconnected to atmosphere by a port 36a. The slide in its right-hand position puts the pipe 51 in communication with the pipe 53 and the diss charge valve 42 is opened. The moving parts stop. The control valve is turned through 90 degrees and the slide 36 moves towards the left and the discharge valve then closes. At starting the receiver 57 or 57<SP>1</SP> is filled with compressed air and at the same time cut off valves 58, 58<SP>1</SP> are closed by compressed air entering at 61 or 61<SP>1</SP>. When the pressure in the receivers is built up to the desired value the appropriate starting valve is opened by directing compressed air to the control piston 59 or 591.