摘要 |
Hydraulic lifting system especially for the tipping of truck bodies and being of the character in which hydraulic oil is supplied to a tipping cylinder through a stop valve, the valve body (8) of which is connected by e.g. a chain (10) to the movable piston of the cylinder in such a manner that the valve body against the force of a spring (6) is conveyed to rest against a valve seat (7) so that the valve will close immediately before the highest point of the tipping piston is reached. The chain (10) is connected to one end of a reciprocating manoeuvre rod (5) which by the said spring (6) is squeezed to a position from which it will prevent the valve body (8) to reach the valve seat (7), but by a pull of the chain will be led away from the valve seat. The valve body (8) and the manoeuvre rod (5) can be designed in such a manner that their mutual contact surface is smaller than the end surface of the manoeuvre rod turning towards the valve body, so that the oil can be pressed against the end surface. |