GB817436A - Improvements relating to starting mechanism for internal combustion engines - Google Patents

Abstract

817,436. Starting. RODICK, A. J., POUNDER, C. C., and REBBECK, Sir F. E. April 15, 1957, No. 12170/57. Class 7(5) In an internal - combustion engine which is set in motion for starting by the admission of compressed air to the engine cylinder combustion spaces through a starting valve assembly which includes a starting valve opened by starting air and closed by a closing air pressure in a pipe line controlled by a pilot valve which is under control of the engine starting and stopping control gear, means for locking the starting mechanism comprises a pneumatic interconnection between the pilot valve and an interlock valve which opens the pipe line to atmosphere when pre-start conditioning apparatus is correctly set for starting the engine thus releasing the closing air pressure and permitting the starting valve to open when the engine control gear is in the start position the interlock valve being controlled by the pre-start conditioning apparatus to pressurize the pipe line and lock the starting valve against opening when the apparatus is not correctly set for starting the engine. The supply of starting air may be prevented if the engine turning gear has been inadvertently left in the engaged position and/or there is a fault in the lubricating and/or cooling systems. When the interlock valve is under control of the engine lubricating and/or cooling system, the interlock valve may be actuated by fluid pressure in the system. As shown with the turning gear 2, 3 in working position the stem of valves A<SP>1</SP>, A<SP>2</SP> is displaced so that the valve A<SP>1</SP> is open and the valve A<SP>2</SP> is closed. If an attempt is made to start the engine by admitting starting air from the reservoir 5 to the starting system and moving the engine control gear to start position the cam 4 will be moved to the position shown in which the pilot valve member 10 is raised off its seat and air under pressure from the reservoir 5 will be admitted to the top of the piston 17 of the starting valve assembly by way of pipe E, interlock valve assembly A and passage 23, pipe D, pilot valve assembly B and pipe F so that the pressure on the top of the piston 17 will hold the starting valve closed on its seat and starting air cannot pass through the pipe 6 to the engine cylinders. When the turning gear is disengaged the valves A<SP>1</SP>, A<SP>2</SP> will be displaced to the right and the pressure in the pipe F is released thus allowing the starting valve to open. In the stop position the valve 10 is lowered and starting air will again hold the starting valve closed.