| 摘要 |
PURPOSE:To prevent hunting and a sudden increase in pressure in a circuit by bending a spring positioned forward in the moving direction and bending a spring positioned in the rear when a spool is moved from the neutral position. CONSTITUTION:In a switch valve where a valve body (a) comprising a body 12 and covers 13, 14 fixed to both ends of the body incorporates a spool 15 in such a manner as to freely slide, circular gooves 35, 36 are formed on both ends of the spool 15, and each pair of spring sheets 43, 44; 45, 46 are slidably fitted in the respective grooves 35, 36. Compression springs 49, 50 are interposed between the sheets 43, 44 and between the sheets 45, 46, respectively, thereby to retain the spool 15 at the neutral position when the above pilot pressure chambers 51 52 are in the state of tank pressure. When the spool 15 is moved from the neutral position to the right, for example, the spool is moved against the spring 50 for the travel L1, and moved against the springs 49, 50 for more than the travel L1. |
