Classification of power take-off devices

According to different control methods, there are mechanical control, hydraulic control, pneumatic control, vacuum source control, electronic control and other manipulation methods for power take-off, among which pneumatic control is more common. According to different forms of power output, it can usually be divided into transmission side power output form, transmission front power output form, transmission rear power output form, and engine front power output form. The power output form of the transmission side is generally output by a gear on the intermediate shaft of the transmission, or by the reverse cam, due to structural limitations. This power output method can only output half of the maximum power of the engine, at most not exceeding half. Therefore, it is called partial power output and is commonly used in dump trucks, garbage trucks, high-altitude operations, crane trucks, and oil tank trucks. The operation can be manually operated mechanically, or controlled by pneumatic, hydraulic, electromagnetic control switches for engagement and disconnection, or by push-pull flexible shafts. The front power output form of the transmission is set between the transmission and the clutch, which can obtain the maximum power of the engine, hence it is called a full power output power take-off. The design of this power take-off must focus on oil temperature and lubrication, and if necessary, forced lubrication and cooling devices can be added. This structure makes the modification of fire trucks more convenient. The power output form at the rear of the transmission can be roughly divided into the power output form at the rear end of the intermediate shaft and the power output form at the rear end of the second shaft. 1. The power take-off at the rear end of the intermediate shaft is directly fixed on the rear end face of the transmission. A spline or a gear is made at the rear end of the intermediate shaft of the transmission for power output, which can extract the maximum power of the engine. 2. The power take-off of the second shaft output form is fixed on the rear end face of the transmission, and a gear is installed at the output end of the second shaft as the power output, which can obtain the maximum power of the engine, and the speed can be changed by the gear position of the transmission, but the structure is relatively complex and the modification of the transmission is relatively large. The above two types of transmission rear end power output are commonly used in fire trucks, concrete mixer trucks, pump trucks, and forklifts. The power output form of the front part of the engine is generally from the crankshaft pulley at the front end of the engine, using a triangular skin to output power and drive the power take-off. This output method can take power at any time, but it is only a partial power output. It is mostly used in mixer trucks, as well as power take-off devices for free wheel power output and transmission shaft power output.

The above:  Introduction to A7V inclined axis variable displacement piston pump