Abstract: The present disclosure relates to a thermostat fault diagnosis method. The method includes: a current environment temperature and a boundary temperature and initial opening temperature corresponding to the current environment temperature are acquired; engine thermal equilibrium state data determined based on coolant temperature change data in an engine are acquired; a current coolant temperature is acquired; and according to the engine thermal equilibrium state data and a relationship between the current coolant temperature and the boundary temperature and initial opening temperature, it is judged whether a thermostat is faulty.

Abstract: The present disclosure relates to a thermostat fault diagnosis method. The method includes: a current environment temperature and a boundary temperature and initial opening temperature corresponding to the current environment temperature are acquired; engine thermal equilibrium state data determined based on coolant temperature change data in an engine are acquired; a current coolant temperature is acquired; and according to the engine thermal equilibrium state data and a relationship between the current coolant temperature and the boundary temperature and initial opening temperature, it is judged whether a thermostat is faulty.

Abstract: A method for calculating Atkinson cycle intake flowrate of an internal combustion engine includes determining an intake stopping point and an engine crank angle corresponding to a piston position of the internal combustion engine at the intake stopping point; calculating mass and partial pressure of an exhaust gas and a fresh gas within a cylinder from the engine crank angle; obtaining a mass ratio of a quantity of gas pushed out of the cylinder by a piston to a total quantity of gas within the cylinder at the intake stopping point during a period of time starting from the intake stopping point until intake valve closure; and calculating intake flowrate of the fresh gas within the cylinder at the intake valve closure from the mass ratio obtained. Also disclosed is a system for calculating Atkinson cycle intake flowrate of an internal combustion engine.

Abstract: A continuously variable valve lift system includes a driving swing arm, a camshaft, a valve structure, a control shaft and an adjusting swing arm. The valve structure includes a roller rocker arm and a valve connected to the roller rocker arm. The driving swing arm has a driving arc surface. The driving arc surface contacts with the roller rocker arm to drive the valve to perform a reciprocating movement. The driving swing arm is sleeved on the control shaft and is capable of swinging around the control shaft. The control shaft is provided with a mounting part. The adjusting swing arm is connected to the mounting part and is capable of swinging relative to the mounting part. The adjusting swing arm is disposed between the camshaft and the driving swing arm. Two sides of the adjusting swing arm are contacted respectively with the camshaft and the driving swing arm.

Abstract: A continuously variable valve lift system includes a driving swing arm, an adjusting member, an adjusting swing arm and a camshaft. The driving swing arm is provided with a first connecting part, the adjusting member is provided with a second connecting part, and the adjusting swing arm is provided with a third connecting part, wherein two sides of the second connecting part abut against the first connecting part and the third connecting part, respectively, the second connecting part abuts against the third connecting part to form a spiral surface therebetween, and the adjusting member is further capable of sliding along an axial direction of the middle shaft, and the camshaft contacts with the adjusting swing arm.

Abstract: A combustion control method and a combustion control system with variable excess air coefficient for gasoline engine are provided. The combustion control method with variable excess air coefficient for gasoline engine comprises steps as follows: monitoring engine operating condition; determining current engine load condition based on the engine operating condition, wherein the engine load condition comprises part load, high load, and full load conditions; and selecting an appropriate excess air coefficient combustion mode in accordance with the current engine load condition; wherein the engine uses lean combustion mode with excess air coefficient of 1.6˜2.0 when the current engine load condition is the part load condition; the engine uses combustion mode with excess air coefficient of 1 when the current engine load condition is the high load condition; and the engine uses combustion mode with excess air coefficient of 0.8˜0.9 when the current engine load condition is the full load condition.

Abstract: A method for calculating Atkinson cycle intake flowrate of an internal combustion engine includes determining an intake stopping point and an engine crank angle corresponding to a piston position of the internal combustion engine at the intake stopping point; calculating mass and partial pressure of an exhaust gas and a fresh gas within a cylinder from the engine crank angle; obtaining a mass ratio of a quantity of gas pushed out of the cylinder by a piston to a total quantity of gas within the cylinder at the intake stopping point during a period of time starting from the intake stopping point until intake valve closure; and calculating intake flowrate of the fresh gas within the cylinder at the intake valve closure from the mass ratio obtained. Also disclosed is a system for calculating Atkinson cycle intake flowrate of an internal combustion engine.

Abstract: An air intake duct includes an air intake duct body (11) which includes an air intake part (111) and a connecting part (112) connected with the air intake part (111). A first channel is formed inside the air intake part (111), a second channel intercommunicating with the first channel is formed inside the connecting part (112), one side of the connecting part (112) is provided with a connecting surface (112a) which inclines towards an axis of the air intake duct body (11), the connecting surface (112a) is inclined and extended from a connection joint of the connecting part (112) and the air intake part (111) to an end portion of the connecting part (112), and the first channel has a larger cross section area than the second channel.

Abstract: A continuously variable valve lift system includes a driving swing arm, a camshaft, a valve structure, a control shaft and an adjusting swing arm. The valve structure includes a roller rocker arm and a valve connected to the roller rocker arm. The driving swing arm has a driving arc surface. The driving arc surface contacts with the roller rocker arm to drive the valve to perform a reciprocating movement. The driving swing arm is sleeved on the control shaft and is capable of swinging around the control shaft. The control shaft is provided with a mounting part. The adjusting swing arm is connected to the mounting part and is capable of swinging relative to the mounting part. The adjusting swing arm is disposed between the camshaft and the driving swing arm. Two sides of the adjusting swing arm are contacted respectively with the camshaft and the driving swing arm.

Abstract: A continuously variable valve lift system includes a driving swing arm, a camshaft, a valve structure, a middle shaft, an adjusting member and an adjusting swing arm. The driving swing arm, the adjusting member and the adjusting swing arm are sleeved on the middle shaft and are respectively capable of swinging around the middle shaft. The first connecting part, the second connecting part and the third connecting part are arranged sequentially along a circumferential direction of the middle shaft. The second connecting part is located between the first connecting part and the third connecting part, and two sides of the second connecting part abut against the first connecting part and the third connecting part, respectively. The second connecting part abuts against the third connecting part to form a spiral surface therebetween. The adjusting member is further capable of sliding along an axial direction of the middle shaft.