Mechanical Powerflow From The Torque Converter To The Turbine Shaft - Engine Running: Notes

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The mechanical power flow in the Hydra-matic transmission begins at the point of connection between the torque converter and the engine flywheel. When the engine is running, the torque converter is forced to rotate at engine speed. As the torque converter rotates it multiplies engine torque and transmits it to the turbine shaft (568). The turbine shaft provides the primary link to the mechanical operation of the transmission. The Hydra-matic 10 Speed RWD automatic transmission requires a constant supply of pressurized fluid to cool and lubricate all of the components throughout the unit. It also requires a holding force to be applied to the clutches during the various gear range operations. The torque converter, fluid pump assembly (25) and the control valve assembly (12) provide for the pressurization and distribution of fluid throughout the transmission.

1. Power from Torque Engine

Torque from the engine is transferred to the transmission through the engine flywheel which is bolted to the engine crankshaft.

2. Power to Drive the Fluid Pump

The fluid pump assembly (25) is splined to the Automatic Transmission Fluid Pump Driven Gear (23) which is driven by the Automatic Transmission Fluid Pump Idler Gear (405) which is driven by the Automatic Transmission Fluid Pump Drive Gear (403) which is keyed to the torque converter hub. Therefore, the fluid pump assembly also rotates at engine speed.

3. Fluid Coupling Drives the Turbine

Transmission fluid inside the torque converter (1) creates a fluid coupling which in turn drives the torque converter turbine.

4. Turbine Shaft Driven

As the torque converter turbine rotates, the turbine shaft (568), which is splined to the torque converter turbine, is also forced to rotate at turbine speed.