TRANSMISSION AR 5189384 - Caterpillar

Illustration 1 g01560674
Propel Motors (1) Speed sensor (2) Final drive (3) Flushing spool (4) Flushing relief valveEach propel motor is a piston-type motor with two speeds. A propel motor drives each wheel through a planetary final drive that is single speed. The ports on the motors are marked for identification. Port "A" on both motors is the reverse port. Port "B" on both motors is the forward port. Port "M3" on both motors is the shift port. Each motor is equipped with a speed sensor. A gear on the output shaft of the motor rotates past the tip of the speed sensor. When a tooth passes the sensor, an electrical impulse is sent to the machine ECM. The machine ECM converts the frequency of the electrical impulses to a vehicle speed. Each propel motor contains a flushing valve. Flushing valves direct oil from the low pressure side of the propel loop to the flushing relief valve. The flushing relief valves open when the pressure in the low pressure side of the propel loop is greater than the flushing relief pressure setting. Each flushing relief valve directs a metered amount of oil from the low pressure side of the loop into the motor case drain. The case drain line on each motor directs oil from the motor cases to the cooler bypass manifold.
Illustration 2 g01560675
Cross Section of the Propel Motor (5) Cylinder block (6) Minimum displacement screw (7) Case drain (8) Output shaft (9) Synchronizing shaft (10) Speed sensor (11) Piston (12) Maximum displacement limiter (13) Line from shift solenoid (14) Flushing relief valve (15) Flushing spool (16) Feedback linkage (17) Servo piston (18) Valve segmentThe right propel motor and the left propel motor are identical. Each propel motor is a piston-type motor with two speeds. The motor contains a flushing valve for the closed loop circuit. The shift solenoid on the auxiliary manifold determines the speed range of the motor. The motor is internally pilot operated. This will keep pressure against the servo piston in order to effect the low motor speed.The feedback linkage attaches to the center of the servo piston. As the servo piston shifts downward, the feedback linkage shifts downward. One end of the feedback linkage is attached to the valve segment. As the servo piston and the feedback linkage shifts downward, the valve segment shifts downward. The servo piston and the valve segment continue moving until the servo piston contacts the maximum displacement limiter. When the servo piston contacts the maximum displacement limiter, the motor is at maximum displacement. This position corresponds to low speed and maximum torque of the motor.Supply oil from the propel pump in the high pressure circuit enters the piston cavity in the cylinder block. The pump supply oil forces the pistons to move out of the piston chamber. This causes the cylinder block to rotate. The synchronizing shaft transfers the rotation of the cylinder block to the motor output shaft. The output shaft transmits power to the final drive assembly.High pressure