Dual filter pump assembly

Abstract

A dual filter pump assembly provides a portable, typically hand-powered vacuum and pressure pump that alternatively creates a vacuum or negative pressure and positive pressure which force a liquid to be filtered through various passageways and chambers in a base and through a coarse filter medium and a micro filter medium. A lower check valve and an upper check valve maintain synchronized communication between the passageways, such that there is sufficient pressure and flow regulation to force the liquid through micro-sized pores in the generally flow restrictive micro filter medium. The micro-sized pores may be susceptible to inhibiting the flow of the liquid, and consequently generate pressure build up inside the pump and filter chambers. In some embodiments, a relief valve may help release the excess fluid pressure build up in the pump and filter chambers. The relief valve may additionally provide an indication of when the micro filter medium requires cleaning, such as in the event that some of the liquid exits a relief port in the relief valve.