| 摘要 |
PURPOSE:To enable a cylinder unit of a thrust protector to be subjected to operation test even in running by providing a second piston having a nozzle in a first piston and providing an oil pressure change-over valve in a pressurized oil supply line of each piston. CONSTITUTION:A first piston 25 is provided in a cylinder 24 chamber of a cylinder unit 23, and a second piston 26 having a nozzle 43 is provided in the first piston 25. The nozzle 43 is disposed close to the slant peripheral side surface of a rotor collar 22 of a rotor 21. On the way of lines 30, 47 for supplying and discharging pressurized oil in the cylinder 24 are provided oil pressure changeover valves 35, 49. In the operation test of the cylinder unit 24 an oil pressure change-over valve 35 or 49 is changed over so that whether or not the first piston 25 is moved to be kept away from the rotor 21 or approach the rotor 21 can be tested. Then, the second piston 26 is moved to increase a gap G between said piston 26 and the rotor collar 22. |
