Hydraulic Oil Pump for 9DCT

Mechanical oil pump+electric auxiliary oil pump
The mechanical oil pump+electric auxiliary oil pump is also known as a dual pump system. Due to the fact that the power and flow requirements of the gearbox for hydraulic oil vary from time to time based on the load, with peaks and valleys. When there is only a mechanical oil pump, the mechanical oil pump will be designed according to the highest demand. Although there is a variable displacement oil pump, the power and displacement of the mechanical oil pump will still be too large, and in many cases this design will generate energy waste.
After using an electric auxiliary oil pump, the power and displacement of the mechanical oil pump can be designed based on the basic load, with the displacement reduced by about 1/3. The peak load is supplemented by the electric auxiliary oil pump, which supplies oil as needed.
In this way, the losses caused by the residual design of the mechanical oil pump can be greatly reduced. It can also maintain the energy required for the transmission to work when the engine is stopped, continue to provide a certain amount of oil pressure, and maintain or quickly enter the operating state of the transmission. The transmission can continue to supply oil to components during startup, shutdown, and coasting modes, regardless of the engine speed, It can also improve the responsiveness of clutch re engagement during engine restart.

Critical parameters:

Classification and function of automatic transmission oil pump:

The car automatic transmission consists of numerous moving elements which require not only high-quality lubrication, but also efficient cooling. All this work is performed by the transmission lubrication system which is based on the transmission oil pump. This efficient transmission component helps to maintain the necessary system pressure and to increase the efficiency of lubrication with increasing RPM rate of the engine shaft.

Currently, automatic transmissions are equipped with two main types of oil pumps:

-gear oil pump

-vane pump

Each of these types of oil pumps has its own pros and cons. Nowadays, most modern transmissions are equipped with advanced pumps that ensure optimal pressure maintenance inside the lubrication system.

The oil pump performs the following functions:

- builds up the main pressure for the hydraulic control unit;

- generates oil pressure for the torque converter with the purpose to prevent cavitation;

- flushing of the torque converter with oil to eliminate heat;

- supply of oil under pressure to the hydraulic control system as well as to the gear shifting elements.