Valve rocker arm assembly, variable air distribution mechanism and engine

A variable valve train mechanism, comprising a valve rocker arm, a camshaft and an engine valve, wherein the valve rocker arm is a valve rocker arm assembly comprising:

• an oil inlet hose;
• a rocker arm shaft, wherein an oil drain channel, an oil return groove and a first oil path are provided in the rocker arm shaft, and the oil drain channel is in communication with the oil return groove through the first oil path;
• a first rocker arm, which is rotatably connected to the rocker arm shaft;
• a second rocker arm, which is rotatably connected to the rocker arm shaft, wherein the first rocker arm and the second rocker arm are located in a same rotation plane, the second rocker arm is provided with a piston chamber, an oil inlet path, an oil drain path and a piston, the piston is slidably arranged in the piston chamber, an extension end of the piston is configured to extend out of the piston chamber and push the first rocker arm, one end of the oil inlet path and one end of the oil drain path both are in communication with a space of the piston chamber located at a bottom of the piston, another end of the oil inlet path is connected to the oil inlet hose, and another end of the oil drain path is alternately connected with or disconnected from the oil return groove as the second rocker arm swings during a swing cycle of the second rocker arm;
• a unidirectional communication device, which is provided in the oil inlet path and/or the oil inlet hose, and an oil-guiding direction of the unidirectional communication device is toward the piston chamber;
• and
• a control valve, which is connected with the oil drain channel and is configured to actively control communication between the oil drain channel and the oil return groove;
• one end of the first rocker arm of the valve rocker arm assembly is in driving connection with the engine valve, and one end of the second rocker arm of the valve rocker arm assembly is in driving connection with the camshaft.

An engine comprising a valve train mechanism, wherein the valve train mechanism comprises a valve rocker arm assembly, a camshaft and an engine valve, and the valve rocker arm assembly comprises:

• an oil inlet hose;
• a rocker arm shaft, wherein an oil drain channel, an oil return groove and a first oil path are provided in the rocker arm shaft, and the oil drain channel is in communication with the oil return groove through the first oil path;
• a first rocker arm, which is rotatably connected to the rocker arm shaft;
• a second rocker arm, which is rotatably connected to the rocker arm shaft, wherein the first rocker arm and the second rocker arm are located in a same rotation plane, the second rocker arm is provided with a piston chamber, an oil inlet path, an oil drain path and a piston, the piston is slidably arranged in the piston chamber, an extension end of the piston is configured to extend out of the piston chamber and push the first rocker arm, one end of the oil inlet path and one end of the oil drain path both are in communication with a space of the piston chamber located at a bottom of the piston, another end of the oil inlet path is connected to the oil inlet hose, and another end of the oil drain path is alternately connected with or disconnected from the oil return groove as the second rocker arm swings during a swing cycle of the second rocker arm;
• a unidirectional communication device, which is provided in the oil inlet path and/or the oil inlet hose, and an oil-guiding direction of the unidirectional communication device is toward the piston chamber;
• and
• a control valve, which is connected with the oil drain channel and is configured to actively control communication between the oil drain channel and the oil return groove;
• one end of the first rocker arm of the valve rocker arm assembly is in driving connection with the engine valve, and one end of the second rocker arm of the valve rocker arm assembly is in driving connection with the camshaft.