ELBOW 0008836 - Caterpillar

Illustration 1 g00854750
Steering motor (1) Pivot pin (2) Pistons (seven) (3) Case drain port (4) Barrel (5) Port plate (6) Case (7) Head (8) Passage (lubricating oil for the pivot pin) (9) Retaining plate (10) Shaft (11) Bearing (12) Ring (13) Bearing (14) Shims (15) Snap ring and shims (16) Cover
Illustration 2 g01214588
The steering motor is located between the counterbalance valve and an adapter. The adapter is attached to the frame below the operator's station.The steering motor is a fixed displacement bent axis motor of the piston type. The steering motor is operated by oil from the variable displacement piston pump. The steering motor can produce the same amount of output torque in either direction.Oil flow through the steering motor can be in either direction. A change in the direction of oil flow causes a change in the direction of rotation for barrel (4), for pistons (2), and for shaft (10) .The following components are the parts of the motor that turn: shaft (10), snap ring and shims (15), retaining plate (9), pistons (2) and barrel (4). The parts that do not turn are the following components: head (7), case (6), port plate (5), shims (14), ring (12) and cover (16) .Oil from the pump flows to the steering motor through the steering control valve and through the counterbalance valve. Then, oil flows through the inlet control slot in head (7) to the inlet control slot in port plate (5) .Note: The direction of rotation determines the inlet and the outlet of the two slots in head (7). Likewise, the direction of rotation determines the inlet and the outlet of the two slots in port plate (5) .Oil through port plate (5) flows into the cylinders of barrel (4) that are over the inlet control slot of port plate (5) .The cylindrical ends of pistons (2) are held in sockets in shaft (10) by retaining plate (9). The sealed end of pistons (2) are positioned in barrel (4). Barrel (4) rotates around pivot pin (1), which is at a fixed angle of 40 degrees to the axis of shaft (10). Because the steering motor is a bent axis type motor, seven pistons (2) move in and out of the cylinders as oil leaves the cylinders and as oil enters the cylinders. The motion forces the pistons to rotate around pivot pin (1). Rotation of the pistons forces shaft (10) and barrel (4) to rotate.As shaft (10), pistons (2), and barrel (4) continue rotation, the pistons reach the top center (full retracted position). At the same time, the cylinder begins to overlap the outlet control slot in port plate (5). The piston begins to move downward. Because the piston moves downward, the piston pushes oil out of the cylinder, into the outlet control slot in port plate (5), and through the outlet control slot in head (7). The same oil is then pushed to the counterbalance valve, to the steering control valve, and to the tank. The ball end