Designing an energy-saving pneumatic vacuum pad using computational fluid dynamics for automated manufacturing system

Abstract

The current paper is concerned with the development of a new energy-saving vacuum pad using computational fluid dynamics (CFD)-technique. CFD which is a powerful tool to provide an effective insight into the flow field numerically. Nowadays, application of pneumatic vacuum pads may be found in many different real industries, especially in the field of automated manufacturing system, like the automatic conveyer system, automatic assembly line, semiconductor industry as well as wafer factory, etc. Traditional vacuum pads generally utilize nozzles to create the effect of vacuum. In the current paper, however, a new idea to generate the effect of vacuum is proposed by designing a structure similar to that of an aerostatic bearing. In details, the air is guided to flow through a well-designed restrictor inside the vacuum pad and flow out through the outlet between the vacuum pad and the sucked workpiece. Therefore, according to Bernoulli's equation, the air pressure near the centre-line of the vacuum pad decreases because of the increased airflow velocity. Consequently, the effect of vacuum is generated. To achieve two preset requirements, that is, large suction-force output and low air consumption, the commercial CFD-RC software is utilized to simulate the airflow field and design the optimal geometry inside the vacuum pad. Experimental results further prove that the new vacuum pad with two significant features is successfully developed and implemented in the current study.