DEVICE FOR DISCHARGING FIXED QUANTITY OF LIQUID

摘要

A device for discharging a fixed quantity of liquid, discharging at a time a fixed quantity of liquid in a container and having a negative pressure system causing negative pressure to act on liquid in the container while the liquid discharge is stopped. The negative pressure system for causing negative pressure to act on the container is constructed from a negative pressure generation means, an electro-pneumatic regulator for communicating with the negative pressure generation means and regulating the inside of the container to a desired negative pressure, a pressure sensor provided between the electro-pneumatic regulator and the container, and a control means for controlling the electro-pneumatic regulator based on a signal from the pressure sensor to regulate the inside of the container to the desired negative pressure. Stable negative pressure can be obtained immediately after the power for the device for discharging a fixed quantity of liquid is turned on so that the device is usable immediately after the power is on.