| 摘要 |
PURPOSE:To attain accurate gas quantity detection by disposing a plurality of liquid level detecting units having small heaters within a gas-storage chamber at different levels. CONSTITUTION:Each liquid level detecting unit 11 has a built-in small heater and is attached to the lower end of a holding member 12 fixed to a partition plate 2a which constitutes a gas storage chamber 2. A plurality of liquid level detecting units 11 are thus disposed at different levels between each other. A controller indicator 13 is associated with the liquid level detecting units 11 by electrical means to detect the respective temperatures of the heaters of the liquid level detecting units 11. The controller indicator 13 detects if the liquid level detecting units 11 are above or below the liquid level on the basis of the temperature of the heaters so that the level of the surface of a processing liquid 4b is determined. |
