Piezo activated pump in an ink liquid supply system

摘要

A piezo activated liquid supply pump system includes a cylinder shaped vibration pipe made of a piezo element, and a cone shaped pressure chamber surrounded by a rubber wall. The cone shaped pressure chamber is disposed in the cylinder shaped vibration pipe in a manner that a cavity is formed therebetween. Polyethylene glycol is filled in the cavity for transferring the vibration of the piezo element to the rubber wall of the cone shaped pressure chamber. The volume of the pressure chamber varies in response to the vibration of the piezo element to achieve the liquid supply. The cone configuration of the pressure chamber ensures an effective removal of air bubbles from the pressure chamber. The cavity is communicated with a buffer chamber so as to introduce the polyethylene glycol into the buffer chamber when the liquid contained in the pressure chamber freezes, whereby the expansion of the pressure chamber caused by the freezing of the liquid is absorbed.