| 摘要 |
PURPOSE:To stabilize tilt down operation through prevention of the occurrence of jerk phenomenon by a method wherein a throttle valve is installed in a flow passage through which the upper chamber of a tilt cylinder and release valve on the upper chamber side are intercommunicated. CONSTITUTION:A flow passage 46 on the cylinder first upper chamber side is communicated with the upper chamber 28B of a tilt cylinder 28 through a flow passage 47 on the cylinder second upper chamber extending to the upper chamber 28B side of the tilt cylinder 28. The flow passage 46 on the cylinder first upper chamber side and the flow passage 47 on the cylinder second chamber side are formed as an internal flow passage in a cylinder housing 20. An orifice 88 serving as a throttle part is located in a flow passage through which the flow passage 46 on the cylinder first upper chamber side and a release valve 43 on the upper chamber side. This constitution prevents the occurrence of jerk phenomenon to execute stable tilt down operation. |
