| 摘要 |
PURPOSE:To enable accurate measurement without lowering reliability in detecting a penetration amount in high sensitivity by reducing the change in the surface tension of mercury, by controlling a pressure changing speed on the basis of the change rate of the temp. in a pressure chamber. CONSTITUTION:A specimen W is preliminarily inserted into a specimen cell 1 which is then evacuated to be filled with mercury. This cell 1 is placed in the pressure chamber 4 filled with oil 3 and hermetically closed. At first, a control signal for operating a pressure amplifier 6 to a pressurizing direction at a predetermined speed is outputted from a control part 5 to increase the pressure in the pressure chamber 4 while the temp. in the pressure chamber 4 is raised by the adiabatic compression and dissolution of gas mixed in the oil 3. A pressure detecting value and a temp. detecting value are momentarily supplied to the control part 5 and temp. change is calculated and stored at each constant pressure change while, based on this data, a pressure increase speed for preventing the temp. in the pressure chamber 4 from exceeding the preset temp. range is operated and the amplifier 6 is operated by said speed. Therefore, mercury 2 continuously changes from atmospheric pressure to high pressure in a set tolerant temp. to high pressure in a set tolerant temp. range. In addition, reduced pressure measurement is similarily performed. |
