RESEARCH ON A NEW TYPE OF ENERGY SAVING PNEUMATIC PISTON VACUUM GENERATOR

Abstract

Currently used jet vacuum ejector has a defect of high air consumption due to its requirement of continuous air supply. Focusing on this problem, a new type of piston vacuum generator (PVG for short) has been researched. The PVG has two pairs of pistons. One is for driving and another is for vacuum generating. Besides the maximum vacuum value, the vacuum response time and air consumption are the most concerning performances. Special structural design is made so as to meet all the requirements, in which the unequal diameters of pistons, using directional control valves instead of the check valves and stepped flow rate control scheme are proposed and realized. Experimental results have shown that for the prototype of piston vacuum generator its maximum vacuum is about 93kPa, the response time is about 3.7s and the air consumption is reduced by about 71.3% in time interval of 60s compared to the same level of vacuum ejector.