Specifications

80
6.6 Tilt lock valve operation
Tilt lock valve is used for preventing the shaking of the mast (because the tilt
cylinder maybe cause the inside negative pressure), at the same time, it can avoid the
danger that the mast will be tilted due to the wrong operation (hit the tilt operation staff)
when the engine is off. In traditional structure, even if the engine is off, the mast will be
pitch if someone hit the tilt operation staff. But using this new-style tilt lock valve, in
spite of the strength that push the tilt operation staff, this complexion will be not
occurred. Tilt lock valve structure, see Fig.6.9. In the picture, the port A is connect with
the front of the tilt cylinder and the port B is with the behind. When pull the tilt
operation staff (pull slide valve), the oil that is come from the oil pump will be inpour A,
and the oil that is come from B port will be back to Oil tank. As a result, the mast will
be retroverted. On the other hand, push the tilt operation staff (push slide valve), the
oil that is come from oil pump will be inpour B, recur to the HP oil, the lock valve begin
to work, then Port A can connect with LP, the mast will be pitch. But when the engine
is off, that is, have no HP oil make the lock valve work, so Port A cannot connect with
LP, and the mast will not be pitch, at the last, the tilt cylinder will not be cause the
negative pressure.
Fig. 6.9 Tilt lock valve
T: to oil tank P: to oil pump A, B: to tilt cylinder