Development of Pneumatic Ball Probe (2nd Report)-Evaluative Experiments of Flux Trigger Sensor Type Probe.

In this paper, a novel touch trigger probe which has a totally different construction concept, namely, a pneumatic ball probe has been developed. This touch trigger type pneumatic ball probe consists of a small probe ball, a thin pipe, a pneumatic trigger sensor and a vacuum pump. The fundamental concepts and theoretical analysis of the pneumatic ball probe are described. A prototype of the probe is made and tested. From the experimental tests, the measuring force is reduced to a great extent by using this structure of separating the probe ball from the stylus. The fundamental analysis and the experiment show that it is possible to measure the distance between two walls such as a groove or a drilled hole without restriction of material for two dimension measurement. Using this pneumatic ball probe, it is found that the width between gauge blocks could be measured within a standard deviation of 1.1 μm as well as it is influenced by the vacuum of probe and the inclination of the measurement.