GB843247A - New or improved method of and means for starting diesel engines - Google Patents

Abstract

843,247. Starting diesel engines. DAIMLERBENZ A. G. June 18, 1958 [July 5, 1957], No. 19534/58. Classes 7(2) and 7(5). In a method of starting a four-stroke cycle diesel engine especially with direct injection of fuel into a piston trough, the exhaust passage 6 is closed by a valve 8 disposed as closely as possible beyond the cylinder head whereby the air charge in the cylinder is compressed against the closed valve during the exhaust stroke, the air partly remaining in the cylinder under high pressure and partly flowing back into the induction port during the overlapping opening of the induction and exhaust valves 3, 4, so that during the next intake the cylinder becomes charged with air of higher temperature instead of with cold air and there is a rapid building up of the compression end temperature. The valve in the exhaust passage may be one which is normally used for exhaust braking. In engines having a very small valve overlap a cross connection between the closed exhaust passage and the induction passage or between the induction and exhaust ports in the cylinder head is opened on starting by a cam and valve. On the cam shaft a starting cam may be provided and the cam shaft may be displaceable so that the starting cam can be brought into operative position. The starting cam may be designed to effect a reduction of the maximum compression pressure. Upon bringing the fuel injection into operation the cam shaft may be automatically shifted. A portion of the induction pipe and/or a portion of the exhaust pipe may be heated by a flame unit or electrically.