Daewoo Solar 470LC-V, Shop Manual

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S0707260
Page 3
Swing Motor
GENERAL DESCRIPTION
THEORY OF OPERATION
The cross sectional views of the swing motor, show most of the main components of an axial-piston type
hydraulic motor. Arrows indicating direction of flow and other graphic symbols provide a general guide for
understanding basic operation (Figure 1).
When high-pressure oil enters the cylinder through the inlet port of the valve plate (1, Figure 1), the sliding
piston inside the cylinder is driven back, generating force "F" against the shoe behind the piston (2).
Force "F" acts in two different directions, as indicated by the arrows (Figure 1). Force F1 exerts pressure
directly on the swash plate (3) to generate oil flow through the motor, while force F2 pushes laterally - at a
right angle - against the drive shaft, providing the rotational energy to turn the cylinder block around the
drive shaft.
All nine pistons in the cylinder block have equal width bore, length and volume. They are configured in a
concentric layout around the drive shaft, as shown in the cross section end-view. As oil is forced through
the inlet port, pistons rotating past the pressurized (supply) side of the motor (indicated as the shaded
cylinders) transmit drive torque - one after the next, each in turn - to the swash plate (through F1, direct
output force) and to the cylinder block (F2, lateral force to keep the block rotating).
Figure 1
Reference
Number
Description
1 Valve Plate
2. Shoe
3. Swash Plate
4. Cylinder Block
5. Piston
Reference
Number
Description