LINK AS 7T7586 - Caterpillar

Illustration 1 g02325213
Right travel motor (FORWARD TRAVEL)
(1) Rotary group
(2) Gauge port (service)
(3) Swashplate control piston
(4) Gauge port (stroking pressure)
(5) Line relief valves
(6) External supply port
(7) Counterbalance valve
(8) Check valves
(9) Shuttle valve
(10) Brake pilot valve
(11) Port (pump oil)
(12) External port (parking brake)
(13) Port (pump oil)
(14) Travel motor circuit
(15) Case drain port
(16) Displacement change valve
(17) Gauge port (service)
(18) Internal port (parking brake) The travel motor can be divided into the following three groups:
The rotary group
The displacement change valve
The motor head Rotary Group
Illustration 2 g02325214
Rotary group
(3) Swashplate control piston
(19) Drive shaft
(20) Bearings
(21) Housing
(22) Pin
(23) Pistons
(24) Retainer
(25) Adjustment screw (output flow)
(26) Barrel
(27) Spring
(28) Swashplate The travel motors are piston type motors.The flow of the oil from the pump depends on the direction of travel. The oil from the pump flows into the travel motor through port (11) or port (13). Pump oil is forced out of the travel motor through port (11) or port (13).The case drain oil returns to the hydraulic tank through case drain port (15) on the head of the travel motor.The oil from the drive pump flows into the right travel motor through port (11) during forward travel. The oil from port (11) flows through an internal passage in the motor head. The oil then flows through a passage in swashplate (28) into barrel (26). The oil forces pistons (23) to move to the left.When piston (23) moves, barrel (26) rotates. Oil is discharged through a passage in swashplate (28) by pistons (23) as barrel (26) rotates. The oil flows through an internal passage in the motor head. The oil then flows through port (13). Pistons (23) are connected to output shaft (19) by retainer (24). Output shaft (19) rotates sending power to the final drives.Motor Head
Illustration 3 g02325215
Motor head
(2) Gauge port (service)
(4) Gauge port (stroking pressure)
(5) Line relief valves
(6) External supply port
(7) Counterbalance valve
(8) Check valve
(9) Shuttle valve
(10) Brake pilot valve
(11) Port (pump oil)
(13) Port (pump oil)
(17) Gauge port (service)
(29) Passage
(30) Passage
(31) Passage
(32) Passage
(33) Passage
(34) Spring
(35) Spring
(36) Throttle pin
(37) Poppet
(38) Throttle pin
(39) Spring
(40) Spring
(41) Poppet
(42) Spring
(43) Poppet
(44) Spring
(45) Passage
(46) Poppet
(47) Passage The motor head consists of counterbalance valve (7), crossover relief valves (5), check valves (8), shuttle valve (9) and brake pilot valve (10). The motor head is bolted to the travel motor. The motor head has the following four functions.
The motor head prevents a shock load when travel is stopped.
The motor head prevents overspeed while the machine is travelling down a slope.
The motor head prevents cavitation.
The motor head routes a portion of the oil to the travel parking brake in order to release the brake.During forward travel operation, pump oil is supplied to port (11) from the travel control valve on the main implement valve. The oil flows through an internal passage to check valve (8). A portion of the oil flows to shuttle valve (9). The oil then flows to brake pilot valve (10). Brake pilot valve (10) directs oil to the parking brake. The parking brake is released before the oil from the pump reaches the travel