Unic URW295CR - Telescoping Cylinder 2 Retraction

(4) When Teles coping C ylinder2 retracts
S lide pipe
C heck valve 2
S lide pipe
P iston
R od
S pool
P ressure
Oil
To tank
P ilot
P ressure
C ounter balance
Valve
P iston
Apply"Lock Tight#638".
S elector valve ass’y
C heck valve 2
S elector valve ass’y
R od
C heck valve 1
C heck
valve
Bolt
Tele2
S pool
C heck valve 1
Bolt
Tele3
Tele1
Tele2
Tele3
P ipe for cord reel
C ounte rbalance
valve
After the s et-screw is tightened with Lock T ight #2701
applied、hit with a punch at 2 places on the
circumference and leave it as it is for 1 hour.
How oil flows when tele2 is retracted
P ressure oil flows through the dual cylinder of cylinder rod of tele1
to enter the retraction side of tele2.
Also, the bolt for tele3 opens the check valve 1 of selector valve ass’y
via spool which leads the oil in the extens ion side of tele2 to the counter-
balance valve by way of the slide pipe of tele2, the check valve 2 of s elector
valve ass’y for tele1, and the slide pipe of tele1.
Although the check valve in the counter-balance valve is closed at
this time, the spool is opened by pilot pressure from the retraction side
allowing the oil in the extension side to return to the tank.
This allows the tele2 to retract.
Although pressure is applied to the retraction s ide of tele1 at the
time, the tele1 will not be actuated because the check valve 1 of s elector valve
ass ’y is closed and the passage to the extens ion side of tele1 is shut off.
And the tele3 also will not be actuated according to the same
reas ons as in the tele1.
（１４−４）