Abstract: A gas-pressure-driven apparatus includes a main body having a working chamber, a movable member moving relative to the main body with a pressure of the working chamber, a pressure sensor for detecting the pressure, a flow rate sensor for detecting the flow rate of the working gas. A method for controlling the apparatus includes calculating a pressure change amount from the detected pressure and an integrated flow rate from the detected flow rate when the pressure is changed in a state in which the volume of the working chamber cannot be changed, calculating an initial volume of the working chamber from the pressure change amount and the integrated flow rate, and calculating a post-change volume of the working chamber from the integrated flow rate and the initial volume after creation of a state in which the volume of the working chamber can be changed from the initial volume.

Abstract: A liquid supply system includes a pump having a fluctuating member separating pump and working chambers thereof, a supply and discharge section which supplies a working gas to the working chamber and discharges the working gas from the working chamber, a suction valve, a discharge valve, a pressure sensor for detecting the pressure within a space including the working chamber, a flow rate sensor for detecting the flow rate of the working gas, and a control section. The control section closes the discharge valve and opens the suction valve, calculates a change in the volume of the working chamber from the detected flow rate, controls the supply and discharge section such that the volume change becomes zero, and uses, as an estimated suction-side hydraulic head pressure of the liquid, the pressure detected in a state in which the volume change has becomes zero.

Abstract: A gas-pressure-driven apparatus includes a main body having a working chamber, a movable member moving relative to the main body with a pressure of the working chamber, a pressure sensor for detecting the pressure, a flow rate sensor for detecting the flow rate of the working gas. A method for controlling the apparatus includes calculating a pressure change amount from the detected pressure and an integrated flow rate from the detected flow rate when the pressure is changed in a state in which the volume of the working chamber cannot be changed, calculating an initial volume of the working chamber from the pressure change amount and the integrated flow rate, and calculating a post-change volume of the working chamber from the integrated flow rate and the initial volume after creation of a state in which the volume of the working chamber can be changed from the initial volume.

Abstract: A liquid supply system includes a pump having a fluctuating member separating pump and working chambers thereof, a supply and discharge section which supplies a working gas to the working chamber and discharges the working gas from the working chamber, a suction valve, a discharge valve, a pressure sensor for detecting the pressure within a space including the working chamber, a flow rate sensor for detecting the flow rate of the working gas, and a control section. The control section closes the discharge valve and opens the suction valve, calculates a change in the volume of the working chamber from the detected flow rate, controls the supply and discharge section such that the volume change becomes zero, and uses, as an estimated suction-side hydraulic head pressure of the liquid, the pressure detected in a state in which the volume change has becomes zero.

Abstract: A liquid chemical supply system that performs accurate pressure feedback control and controls the discharge flow rate of liquid chemical with high precision, even when the pressure setting value of the operation pressure differs due to changes in the type of liquid chemical, includes a pump having a pump chamber and an operation chamber separated by a diaphragm comprised of a flexible membrane. The intake and discharge of liquid chemical is performed in accordance with the change in pressure inside the operation chamber. An electro-pneumatic regulator supplies operation gas pressure to the operation chamber. A plurality of pressure sensors having different pressure detection ranges is provided for detecting the operation gas pressure. A controller selectively employs any of the detection results of the plurality of sensors in accordance with the pressure setting value of the operation air that is set for each use, and performs pressure feedback control.

Abstract: [Problem] To always perform accurate pressure feedback control, and control the discharge flow rate of liquid chemical with high precision, even in situations in which the pressure setting value of the operation pressure differs due to changes in the type of liquid chemical, etc. [Means of solution] A pump 11 has a pump chamber 13 and an operation chamber 14 separated by a diaphragm 12 comprised of a flexible membrane, and performs the intake and discharge of liquid chemical in accordance with the change in pressure inside the operation chamber 14. An electro-pneumatic regulator 32 supplies operation air to the operation chamber 14. In addition, in the present system, a plurality of pressure sensors 51, 63 having different pressure detection ranges is provided as pressure detection means for detecting the operation air pressure.

Abstract: The present invention relates to a spin coating apparatus for feeding a clean liquid at a fixed rate. In any of the feeding apparatus in the prior art, no constituent other than a filter has the function of eliminating foreign matter, and the operation of feeding a liquid under precise control is not attained. This results in the problem of the mixing of the foreign matter (and air bubbles) in the feed liquid, and the problem of nonuniformity in a feed speed as well as a feed amount. As expedients for solving these problems, the present invention provides the functions of automatically sensing and excluding factors for the appearances of the foreign matters, and devices for automatically and precisely controlling feed control elements such as a pump, thereby feeding the clean liquid in a constant amount and at a constant speed.