Functional Description - Transmission Oil Pump
DESCRIPTION
| A - Transmission Oil Pump |
| B - Chain and Sprocket |
The transmission oil pump is driven by a chain and sprocket. The oil pump is located just behind the torque converter, inside of the pump housing. The pump is a double-stroke vane pump. The pump has dual chambers, two inlet and two outlet ports. The pump provides necessary lubrication and cooling throughout all phases of transmission operation.
| A - Stator Shaft | E - Central Planetary Shaft for Gear 1 and 2 |
| B - Pump Drive Chain | F - Brake "B" Piston |
| C - Pump Body | G - Pump Drive Hub |
| D - Brake "A" and Housing |
OPERATION
The two graphics to the right show the flow of Automatic Transmission Fluid (ATF) through the pump. The bottom graphic is showing the flow of fluid through the valve that controls the fluid pickup where the redundant return oil (A) meets the passage above the sump (D) in the top graphic.
The Automatic Transmission Fluid (ATF) is drawn from the sump underneath, which has the ATF filter in it. The fluid travels through the intake passage to the mechatronics unit in the pump. The excess oil is diverted through the system pressure valve and low pressure passage back to the ATF pump in the intake duct.
| A - Return of Redundant Oil | D - Sump |
| B - Pressure Pipe | E - System Pressure Valve (In the Valve Body) |
| C - Pump | F - Intake Pipe |
The system delivery valve is managed through the control pressure from the system pressure control solenoid valve. This solution improves the noise, reducing the possibility of cavitation and increasing the pump efficiency by increasing the pressure on the intake side.
| A - Surplus Oil (Charge Duct) from the System Delivery Valve |
| B - Oil from the Filter Built into the Sump |