| 摘要 |
<p>PURPOSE:To provide a pressure intensifying circuit wherein oil pressure is automatically intensified during a high load without resetting rated pressure for an oil hydraulic system. CONSTITUTION:An opening/closing cylinder 4 for a crusher, etc., is connected to an oil pressure pump 13 through an operating valve 12 for direction control. A pilot type check valve 8 which is checking-releasable by pilot pressure from a compression side oil route 28 is provided between oil pressure routes 271, 272 on an extended side running from the operating valve 12 to the opening/ closing cylinder 4. A sequence valve 7 is provided on an oil pressure route 26 diverged from the oil pressure route 271 on the extended side on the operating valve side across the check valve 8, and a pressure intensifying circuit mainly constituted of a distribution valve 6 and a double acting pressure intensifying cylinder 5 is provided in front of it. Pressure intensifying output is restored to the oil pressure route 272 on the extended side on the opening/closing cylinder side across the check valve 8. The distribution valve 6 and a switching valve 10 to reciprocate the double acting pressure intensifying cylinder 5 are operated by communicating guiding oil route 201, 202 provided to a pressure intensifying piston 50 with a pilot oil route 203 or 204 near a stroke end.</p> |
