| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a relief valve for the brake valve of a traveling unit equipped with a free piston avoiding increase of a dimension of a member without damaging an operation function and braking force or stopping force (slope stop performance), maintaining a low pressure relief state, and extending shock-less time. Ž<P>SOLUTION: The relief valve for the brake valve of the traveling unit includes a first space 79a formed on a back side of the free piston 78 in a case body 71 and communicated with a through-hole 76h of a rod 176 through a hole 76a provided on a rear end of the rod 176 in a position not closed by the free piston 78 even when the free piston 78 is in a rear end position; and an oil delivery hole and an oil delivery hole communication passage formed to communicate a second space 79b between a poppet in the case body 71 and the free piston 78 with a flow passage in downstream when an overload pressure is released. The relief valve further includes an overflow passage 180 communicating the first space 79a with the second space 79b, and the overflow passage 180 is closed when the free piston 78 is in a front end position. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
|
