A novel lubricating method of oil pump with self-adaptive adjustment function for transmission

At present, the lubrication of transmission in vehicles cannot be adjusted according to driving conditions, especially vehicles' speed, resulting in low lubrication efficiency and high energy loss. This paper aims to develop a mechatronic system for gearbox lubrication to replace traditional forced and splash lubrication. The mechatronic system can adaptively adjust the flow and pressure of lubricating oil based on the driving conditions to achieve an optimal lubrication effect with less loss. The system mainly includes a Brushless Direct Current (BLDC) motor, inner rotor pump, and drive control circuit. BLDC motor drive control circuit can obtain the current flow of oil pump by monitoring its own speed in real-time, through the pressure sensor and the real-time acquisition of automobile speed so as to self-adaptively adjust the best output flow and pressure based on PID trapezoidal wave control algorithm, which can highly increase the life span of transmission and reduce the energy loss. The results show that the best lubrication effect can be achieved under different working conditions. For example, a vehicle in idle condition consumes only 3.1% power with a conventional oil pump, In addition, an electric lubricating oil pump is monitored in real-time and can alert the driver as long as the pump is in failure. Futher more, the new lubrication method can reduces the gearbox temperature to different degree which is more beneficial to its life extension.