MOTOR AS 5254491 - Caterpillar

Illustration 1 g00732837
Axle Propel Motor (1) Drive shaft (2) Motor case (3) Retainer (4) Pistons (5) Spring (6) Barrel (7) Minimum displacement adjustment screw (8) Head (9) Valve spool (10) Flushing valve (11) Control piston (12) Maximum displacement adjustment screw (13) Control lens (14) Control slot (15) Control slot (16) Pivot PinThe axle propel motor is a variable displacement axial piston motor with a bent axis. The axle propel motor in LOW speed has the following characteristics:
High torque
Large displacementThe axle propel motor in HIGH speed has the following characteristics:
Low torque
Small displacementIn LOW speed, the motor has a displacement of 55 cc/rev (3.35 cu in/rev). In HIGH speed, the motor has a displacement of 28 cc/rev (1.71 cu in/rev). When the machine is shifted from LOW to HIGH, the displacement and the torque of the axle propel motor are decreased by one half. At the same time, the rotating speed is doubled. The axle propel motor can operate in either direction. Four lines are connected to the motor:
Two high pressure loop lines
One displacement selector pilot line
One case drain lineOil is supplied to the axle propel motor by the axle propel pump. The direction of the motor rotation is controlled by the oil flow direction from the propel pump. The displacement and the speed are controlled by the shift valve.The components of the axle propel motor that rotate are drive shaft (1), retainer (3), pistons (4), and barrel (6). The components of the axle motor that do not rotate are motor case (2), head (8), and control lens (13). Spring (5) pushes barrel (6) against control lens (13). This makes a high pressure seal between the barrel and the control lens. A seal is also made between the control lens and the head.When high pressure oil is at the high pressure loop line, oil from the port also flows to control slot (14). Oil in the control slot goes into the cylinders of barrel (6) that are over the control slot. The spherical piston heads are held in the sockets in drive shaft (1) by retainer (3). Seven pistons (4) are held by barrel (6). The barrel rotates around pivot pin (16) which is at an angle to the axis of the drive shaft (1). The design of the bent axis between the barrel and the shaft causes each piston to move. The pistons, the barrel, and the drive shaft rotate as pressure oil enters the cylinders.The pistons are fully retracted when the pistons are in the top center position. The cylinder overlaps control slot (14) on the low pressure side of the loop at this point. When the piston starts to move down, the oil is pushed out of the cylinder. The oil also moves out of the control slot and out of the high pressure loop line. Then, the oil exits to the low pressure side of the loop.The axle propel motor is lubricated by oil leakage from the pistons and the barrel. The axle propel motor operates