Hyundai HX145LCR Manual page 60

(3) Valve block group
The valve block group consists of valve
block (312), valve plate (313, 314) and
spring pin(886).
The valve plate having two kidmey ports
is fixed to the valve block and feeds and
collects oil to and from the cylinder block.
The oil changed over by the valve plate is
connected to an external pipeline by way
of the valve block.
(4) PTO group
PTO group consist of 1st gear (116) and
2nd gear (117), 3rd gear (118).
2nd gear and 3rd gear are supported by
bearings (125, 126), and it can be
mounted to the valve block.
Now, if the drive shaft is driven by a prime
mover (electric motor, engine, etc), it
rotates the cylinder block via a spline
linkage at the same time. If the swash
plate is tilted as in Fig (previous page) the
pistons arranged in the cylinder block
make a reciprocating motion with respect
to the cylinder block, while they revolve
with the cylinder block.
If you pay attention to a single piston, it
performs a motion away from the valve
plate (oil sucking process) within 180
degrees, and makes a motion towards the
valve plate (oil discharging process) in the
rest of 180 degrees. When the swash
plate has a tilting angle of zero, the piston
makes no stroke and discharges no oil.
Concurrently, the auxiliary pump is driven
by gears of PTO.
312
313
Gear case
125
118
125
126
2-8
886
140Z92MP07
Valve block
117
116
140Z92MP08