DIFFERENTIAL 0014139 - Caterpillar

Torque Converter Operation
Illustration 1 g00922011
Flow of power in the torque converter
(1) Rotating housing
(2) Stator
(3) Pump drive gear
(4) Outlet port
(5) Output shaft
(6) Inlet port
(7) Carrier
(8) Impeller
(9) Turbine
(A) Drive components
(B) Driven components
(C) Stationary components The major components of the torque converter are the rotating housing (1), impeller (8), turbine (9), and stator (2).Rotating housing (1) is connected to the engine flywheel by splines. Impeller (8) and pump drive gear (3) are connected to rotating housing (1). Turbine (9) is connected to output shaft (5). Stator (2) is connected to carrier (7). The stator cannot turn.Oil from the manifold group enters the torque converter through inlet port (6) in carrier (7). Oil is directed to the inlet port by a passage in the hub to impeller (8).Impeller (8) turns with rotating housing (1) at engine speed.Rotation of rotating housing (1) throws the oil toward the outside of impeller (8). The oil is thrown around the inside of the converter housing, and against the blades of turbine (9). The oil that hits the turbine blades causes turbine (9) and output shaft (5) to turn. This sends torque through the main drive shaft to the input shaft of the transmission.After the oil hits the turbine blades, the oil goes toward the outside of turbine (9). As the oil goes from the turbine, the oil moves in a direction opposite the direction of the impeller rotation. Stator (2) causes the oil to change direction. The oil then goes back to impeller (8) in the direction of rotation.The force of the oil from the stator can now add to the torque output from the engine to the impeller. This extra force can give an increase to the torque output of the engine to the turbine. A greater difference between the speed of the impeller and the turbine speed causes an increased force of the oil from the stator.The load on the machine changes the speed of the turbine. A higher load causes a larger difference between the speed of the impeller and the turbine speed. The particular load on the machine controls the amount of torque multiplication that can be added by the force of the oil from the stator.Oil from outlet port (4) passes through the torque converter outlet relief valve. The oil then goes to the power train oil cooler. Oil from the power train oil cooler then goes to the steering differential, the brake, the planetary and the brake for lubrication.