GB190802166A - Improvements in Reversible Petroleum and Compressed Air Motors. - Google Patents

Abstract

2166. Berliet, M. Jan. 30. Gas or explosive-vapour engines.-An engine working on a four-stroke cycle is provided with compressed-air admission valves worked from an adjustable cam-shaft for starting, for running with increased power, and for running backwards as a compressed-air engine, the cams for these valves being of special form. A six-cylinder engine is described having three cranks at 120 degrees. A half-speed cam-shaft, not shown, controls the admission and exhaust valves for normal working, and a second cam-shaft 10 controls the compressed-air admission valves 23 of the six cylinders. The shaft 10 is adjustable axially by means of a lever 29, and has three positions. At starting, the lever 29 is brought into the position 32, and cams 33 operate the valves 23 to admit compressed air to all the cylinders on the power out-stroke, the air being discharged on the return stroke through the exhaust valves. On the next out-stroke, carburetted air may be drawn in, and on the following cut-stroke, compressed air is admitted after the explosion, giving increased power. With the lever 29 in the position 31, the valves 23 are not lifted. In the position 30, the cams 39 are brought into action to admit compressed air on alternate revolutions for backward running, the air being discharged through the carburetted-air admission valves. The cams 33, 39 have the profile shown in Fig. 4, the part a-b being in practice ineffective when the engine has attained its normal speed.