| 摘要 |
PURPOSE:To make it possible to detect the piston displacement even in high pressure liquid by providing a slit in a piston rod so that it is slidden in a fixed case, and providing holes at both sides of case which face the slit, and communicating the holes to a hydraulic oil device and a flowmeter. CONSTITUTION:The slit 7 is provided in the piston rod 1 so that it can be slidden in the fixed case 4. The hydraulic oil delivered from the hydraulic oil device 8 goes through a hole A, the slit 7, a gap 10 in the case 4, a hollow port 9, a hole B, and the flowmeter 5, and returns to the original point. At this time, the oil temperature is displayed by a thermometer 6. When a piston 2 is displaced, the opening degree of the gap 10 is changed, and the increase or decrease in the flow rate is displayed by the flowmeter 5. The piston displacement is detected from the change in the flow rate and the oil temperature. The detection can be performed not only in the air but also in the liquid or in the high pressure liquid. |
