ENGINE WITH VARIABLE VOLUME PRECHAMBER OPERATING IN CYCLE WITH MIXED COMBUSTION Russian patent published in 2023 - IPC F02B19/06 

FIELD: internal combustion engines.

SUBSTANCE: engine with a variable-volume pre-chamber, operating in a mixed combustion cycle, contains a variable-volume pre-chamber (6), isolated from the working (2) cylinder by the pre-chamber valve (7), and from the fuel supply system by the fuel supply valve (5). When the piston (1) moves from the bottom dead centre (BDC) towards the top dead centre (TDC) in the working cylinder (2), the air is adiabatically compressed. The plunger (8), moving from TDC towards BDC, increases the volume of the prechamber (6). A portion of fuel is supplied to the prechamber (6), and as a result of adiabatic expansion, the fuel passes from a liquid state to a vapour-gas state. When the plunger (8) reaches the BDC position, the prechamber valve (7) opens and the pressure in the working cylinder (2) is equalized. In the prechamber (6) the formation of a fuel mixture occurs. When the piston (1) moves to the TDC position in the working cylinder (2), adiabatic air compression continues. When the plunger (8) moves from the BDC position towards the TDC in the prechamber (6), adiabatic compression of the fuel mixture is carried out to a temperature that ensures its ignition and combustion of part of the fuel. When the piston (1) is positioned at TDC, the volume formed by the walls of the piston (1), the walls of the working cylinder (2), the walls of the prechamber (6) and the walls of the plunger (8) is minimal. As a result of an increase in pressure in the working cylinder (2) and the prechamber (6), the piston (1) moves from the TDC position towards the BDC. The plunger (8) displaces from the prechamber (6) the mixture of unburnt fuel, air and combustion products formed in it into the working cylinder (2). Heat is removed from the prechamber (6) to the working cylinder (2), where the remaining fuel burns out, accompanied, at constant pressure, by moving the piston (2) towards BDC, and the plunger (8) towards TDC. At the end of fuel combustion, further expansion of combustion products occurs adiabatically. When the plunger (8) reaches TDC, the prechamber valve (7) isolates the prechamber (6) from the working cylinder (2). As the piston (1) passes BDC, exhaust gases are displaced from the working cylinder (2) through the open exhaust valve (4) into the surrounding atmosphere. The cycle in cylinder (2) is carried out in four piston strokes - intake, compression, power stroke, exhaust gases and two revolutions of the crankshaft. The area of the plunger (8) is smaller than the area of the piston (1). The cycle in the prechamber (6) is carried out in two strokes of the plunger (8) - adiabatic expansion and working stroke and in one revolution of the crankshaft. The next cycle of the prechamber (6) is used during the four-stroke cycle of the adjacent working cylinder (10).

EFFECT: increasing the specific engine power and torque.

3 cl, 14 dwg