Patent ID: 7381269

Claim:
A system for supplying a chemical, comprising: a tank for storing the chemical; a dispensing unit having a port through which the chemical flows into and out of the dispensing unit, and a pump operable to pump the chemical into and out of the dispensing unit via the port; a common line extending from the port of the dispensing unit and thereby connected to the dispensing unit; a first line extending from the tank and connected to the common line, wherein the common line and the first line together constitute a refill line that connects the tank to the dispensing unit, and the pump is operable to pump chemical from the tank into the dispensing unit via the port and the refill line; and a second line having a dispensing end from which the chemical is dispensed from the system, the dispensing line connected to the common line, wherein the common line and the second line together constitute a dispensing line that connects the dispensing end of the second line to the dispensing unit, and the pump is operable to pump the chemical out of the dispensing unit via the port and along the dispensing line to the dispensing end of the second line.