| 摘要 |
PURPOSE:To keep a working gas from staying in the cylinder of a tilt-locking device, by connecting the first and second chambers of the cylinder to a gas chamber or the like through by-passes furnished with check valves. CONSTITUTION:To turn a propelling unit to an upper tilted position, a working oil in a cylinder 20 is moved from a first chamber 23 to a second chamber 24 through a first by-pass 33, a first check valve 35, a gas chamber 32, a second by-pass 34 and a second check valve 36. To turn the propelling unit to a lower tilted position, the working oil in the cylinder 20 is moved from the second chamber 24 to the first chamber 23 through the second check valve 36, the second by-pass 34, the gas chamber 32, the first check valve 35 and the first by-pass 33. When a working gas has entered into the working oil in the cylinder 20, the gas is separated from the oil by a buoyant force acting in the gas chamber 32. |
