SELBSTANSAUGENDE DOSIERPUMPE

摘要

A self-priming pump is provided for metering a positive controlled amount of a volatile liquid to a utilization device. The pump comprises a piston means for pumping the liquid from a liquid supply container to a chamber, and from the chamber to a reservoir where the liquid is maintained at a uniform and constant level by an overflow port which drains any excess liquid back to the liquid supply container. The liquid remaining in the reservoir flows through an outlet passage to a well from which the liquid is dispensed in metered units under control of an adjustable needle valve. The needle valve is provided for controlling the rate of feed of the liquid to the utilization device, and is accessible for adjusting the liquid flow while the pump is in operation. The reservoir is also provided with vent means to prevent impediment of liquid flow and, also, to permit liquid flow immediately in response to initial start-up and operation of the pump.