Patent ID: 7988429

Claim:
A chemical liquid supply system comprising: a discharge pump in which a pump chamber filled with the chemical liquid and an operating chamber are divided by a variable volume member, the variable volume member is driven by supplying an operating gas into the operating chamber to decrease the volume of the pump chamber, and the chemical liquid is discharged according to this change of volume; an opening-closing-type discharge-side closure valve provided between the discharge pump and a tip nozzle; a means for switching that switches to either a first state in which the operating gas of a set pressure is supplied to the operating chamber or a second state in which the operating chamber is opened to the atmosphere; a means for chemical liquid supply that delivers the chemical liquid in a hermetically sealed chemical liquid supply container to the discharge pump; a gas source connected to the chemical liquid supply container via pressurized tubing; an opening-closing-type supply-side closure valve provided between the discharge pump and the means for chemical liquid supply; and a means for controlling that controls both of the closure valves and the means for switching so that the supply-side closure valve is switched to a closed position, the discharge-side closure valve is switched to an open position, and the means for switching is switched to the first state when the chemical liquid is to be discharged from the discharge pump; the supply-side closure valve is switched to an open position, the discharge-side closure valve is switched to a closed position, and the means for switching is switched to the second state when the chemical liquid is to be filled into the discharge pump; the timing to switch the discharge-side closure valve to the open position occurs after the means for switching is switched to the first state; and the timing to switch the discharge-side closure valve to the closed position occurs before the means for switching is switched to the second state, wherein another end of a chemical liquid supply tubing, one end of which is connected to the discharge pump, is positioned in the chemical liquid in the chemical liquid supply container, and wherein the means for chemical liquid supply delivers the chemical liquid only by supplying a pressurized gas of a set pressure, greater than atmospheric pressure, from the gas source to a space above the chemical liquid inside the hermetically sealed chemical liquid supply container in a state in which the supply-side closure valve is switched to the open position and the discharge-side closure valve is switched to the closed position.