Takeuchi TB 250, Workshop Manual

Page: 96 / 352

3-15
3
FUNCTION
CYLINDERS
CYLINDERS
The pressure oil alternately flowing into the piston through
the outlet and inlet on both sides (head and rod sides)
causes the piston to perform the reciprocating motion.
For those cylinders with a cushion mechanism, the shock
resulting from the piston colliding with the cover at the
stroke end is dampened by the mechanism.
Cushion mechanism
3LAA01Z
1 2 3 4
3LAA02Z
1 2 3 4
When the piston (1) approaches the stroke end and is likely
to bump into the cover (2), the cushion bearing (3) that is
moving ahead of the piston enters the cushion seal (4).
This shuts off the return passage for the hydraulic oil on the
back of the piston, and thus the oil is expelled only from the
throttle hole or the groove provided in the cushion bearing
(3). This causes the piston (1) backpressure to increase,
slowing the piston speed.