| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve responsiveness by making an accelerating valve small and light and to reduce shock at the time of changing it over. SOLUTION: When a manual selector valve 3 is changed over to #1, a first main valve 5 is closed as pressure from a rod side oil cell 1b is applied to its pilot chamber through an orifice 11, and a second main valve 6 is opened as pressure of its pilot chamber is released to a tank 4b. At this time, oil of a main circuit is supplied to a head side oil cell 1a, return oil from the rod side oil cell 1b joins a head side oil passage 2a through the second main valve 6 and a differential circuit is constituted, a hydraulic cylinder 1 is accelerated, and aa crusher 20 works at high speed and holds an article to be crushed. Consequently, cylinder internal pressure rises and when it reaches set pressure, a pilot sequence valve 7 is changed over and becomes a non-differential circuit, and the hydraulic cylinder 1 reaches the maximum thrust and crushes the article to be crushed.</p> |
