Abstract: The invention relates to a valve which is intended for internal combustion engines and which comprises a valve-head (2) which has formed thereon a circular abutment surface for sealing coaction with a valve seat (9). The valve-head (2) has connected therewith a valve-stem (3) by means of which the valve is moveably journalled in a valve-guide (10). According to the invention, the valve-head (2) has a relatively small wall-thickness, and the valve-stem (3) has provided thereon a collar (16) which on the side thereof distal from the valve-plate (2) has an abutment surface (17) for abutment with a fixed abutment surface.

Abstract: The present invention relates to a method for controlling the working cycle of a four-stroke internal combustion engine which is supercharged by at least one exhaust-driven turbo-compressor (4), and also to an arrangement for carrying out the method. Each cylinder of the engine is provided with an inlet valve (2) to which the compressor (5) of the turbo-compressor (4) delivers air through an inlet pipe (6), and also with an outlet valve (3) from which gases are passed from the cylinder to the turbine (7) of the turbo-compressor (4) through an outlet pipe (8). According to the invention each cylinder is further provided with a pressure control valve (9) which is connected to the outlet pipe (8) by a pressure control line (10), between the outlet valve (3) and the turbine (7) of the turbo-compressor (4).

Abstract: This invention relates to a method and an arrangement for controlling the working cycle of an internal combustion engine (1) which is supercharged by at least one exhaust-driven turbo-compressor (4,5). Each cylinder of the engine has an inlet valve (2) to which air is supplied from the turbo-compressors (4,5) through an induction or inlet line (12), and an outlet valve (3) from which the exhaust gases are passed through an outlet line (13) to the turbo-compressors (4,5). Each cylinder is also provided with a separate pressure control valve (19) which is connected to the induction system by a pressure control line (20) and which is intended to open when the piston, during the compression stroke, is located in a distance from the bottom-dead-center position (C) of the piston, and is intended to close when the piston, during the compression stroke, is located at a second predetermined position (D) in the cylinder at a greater distance from the bottom-dead-center position (C) of the piston.

Abstract: The invention relates to a valve mechanism for controlling a disc valve (1) of an internal combustion engine and comprises a control shaft (2) which is driven by the engine crankshaft, and a push rod (3) which is driven by the control shaft (2) and which for the purpose of transmitting reciprocating movement is connected to one arm (14) of a two-arm rocker (4) which is pivotable about a rocker shaft (15) and the other arm (16) of which rocker transmits these movements to the valve (1). The valve mechanism according to the invention is characterized in that the control shaft (2) is intended to act upon the push rod (3) in both directions of movement thereof; in that the first arm (14) of the rocker (4) extends essentially at right angles to the push rod (3) and the second arm (16) of the rocker extends essentially parallel with the longitudinal geometric axis of the valve (1); and in that a lifting arm (5) is provided for transferring rocker movement to the valve (1).

Abstract: A method for controlling the working cycle of a four-stroke internal combustion piston engine with supercharging and direct fuel injection into each cylinder and with at least one inlet valve and one exhaust valve for each cylinder. The method involves opening the exhaust valve for a second time during each working cycle, in addition to holding the valve open during the exhaust expulsion stroke. According to the invention the exhaust valve is opened and closed for the second time during the compression stroke, the valve being opened when the piston is located in a first predetermined position at a distance form the lower dead center piston position and being closed when the piston is located in a second predetermined position at a distance from the lower dead center piston position greater than the first predetermined position.

Abstract: The invention relates to a valve spring device for a valve in an internal combustion engine. The valve has a valve disc (4) cooperating with a valve seat (5) to control the flow in an engine duct (3), and a valve spindle (6) extending from the valve disc (4). The valve spring device comprises at least one spring (10,11) which is arranged to act between an abutment surface (12) of the engine and an actuating device (8) joined to the valve spindle (6) to bias the valve disc (4) towards the valve seat (5). According to the invention the spring (10,11) consists of a relatively weak helical compression spring. The actuating device (8) is arranged around the valve spindle (6) and is axially displaceable and sealingly guided to form a chamber (15), which at one end is limited by the abutment surface (12) and at the other end is limited by the actuating device (8). The chamber (15) is in communication (24- 27) with the engine duct (3) in which the valve (4,6) is arranged to control the flow.