| 摘要 |
<p>PROBLEM TO BE SOLVED: To control corresponding to a variation in the atmospheric pressure with the use of an economical device without using expensive electric control so as to set a torque of a hydraulic pump in a construction machine. SOLUTION: A pressure at 1atm. is charged in a bell-like container which is expandable and contractible under the atmospheric pressure, having a stationary one end 14a and the other end 14b made into contact with the opened side 13a of a pressure reducing valve 13 in which a spool is displaced in response to expansion and contraction of the container 14 so as to change a secondary pressure. That is, when the atmospheric pressure lowers, the container 14 expands so that the secondary pressure of the pressure reducing valve 13 becomes higher so as to energize a regulator 11. Accordingly, the set torque of the hydraulic pump 11 is lowered, thereby it is possible to reduce a load to an engine.</p> |
