To provide a low viscosity liquid feeding device, with a simple structure and easy in maintenance, capable of delivering a low viscosity liquid at high accuracy.
The low viscosity liquid feeding device is provided with a delivery valve 2, a dye liquid accommodation tank 10 released to the atmosphere, a pipe line 12 arranged between the tank 10 and the delivery valve 2 and conducting the dye liquid to the delivery valve 2, an actuator provided in the pipe line 12 sucking the dye liquid 3 in the tank 10 and press-feeding it to the delivery valve 2, and a pressure sensor 14 for detecting a pressure of the delivery valve 2. The actuator is constituted of a piezoelectric pump 20 with a small pulse and a branched circulation pipe line 16 with a pressure adjusting valve 17 returning to the tank 10 is provided on the pipe line 12 extending from pump 20 to the delivery valve 2. The piezoelectric pump 20 generates almost no pulsation. The circulation pipe line 16 released to an atmosphere reduces the delivery pressure of the delivery valve 2 and absorbs pulsation of the pump 20 and a pressure variation in the pipe line 12a caused by an opening/ closing of the delivery valve 2. Thereby, the delivery pressure is stabilized at a super-low pressure. The delivery pressure is confirmed by the pressure sensor 14 and is adjusted by the pressure adjusting valve 17 such that a value of the pressure sensor 14 becomes a predetermined value. A delivery amount of the dye liquid from the delivery valve is adjusted at high accuracy.
ITO HISASHI
MURAKAMI NOBORU
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