Komatsu Galeo BR380JG-1E0 Shop Manual page 96

10 Structure, function and maintenance standard
Control of delivery
If the swash plate angle (a) becomes larger,
q
the difference between volumes (E) and (F)
b e c o m e s l a r g e r a n d p u m p d e l i v e r y ( Q )
increases.
Servo piston (12) is used for changing swash
q
plate angle (a).
Servo piston (12) carries out linear reciprocal
q
movement according to the signal pressure
from the PC and LS valves.
This linear movement is transmitted to rocker
q
cam (4) via slider (13).
Being supported by cradle (2) on the cylindrical
q
surface, rocker cam (4) slides on the surface
while continuing revolving movement.
Space of the pressure receiving area of servo
q
piston (12) are not identical on the left side and
right side. Main pump discharge pressure (self
pressure) (PP) is always brought to the pres-
sure chamber of the small diameter piston
side.
Output pressure (PEN) of the LS valve is
q
brought to the chamber receiving the pressure
at the large diameter piston end.
The relationship in the size of pressure (PP) at
q
the small diameter piston end and pressure
(PEN) at the large diameter piston end, and
the ratio between the area receiving the pres-
sure of the small diameter piston and the large
diameter piston controls the movement of
servo piston (12).
BR380JG-1E0
SEN01351-00
9