Design of a measurement instrument for non-cylinder pinhole of piston

Some kinds of non-cylinder piston pinhole are introduced. Due to its heavy measurement task with the current instrument, according to its measurement requirements and structural features, a new special measurement instrument for pinhole is developed. To achieve the precision of micron grade, firstly, on the hardware, the high-precision inductive displacement transducer is applied as the probe while the high-rigidity marble slab as the foundation. And the high-accuracy linear guideway and magnetic scale are used. Secondly, on the software, the reliability of data is ensured by the real-time data acquisition card and the multithreading technology. Eventually, aiming at the possible straightness error of the mechanical part, the compensation is added. In addition, this device belongs to the special instrument. Dedicated algorithms are designed respectively for the whole measuring process of pinholes and the corresponding analysis of data. Therefore, the whole process from the placement of the piston to the judgment of the pinhole´s measurement results and the storage of data is automated, which removes the drawbacks of the tedious work and big subjective errors brought by the current instrument. Meanwhile, it is easy to be integrated into the auto production line. At present, this device has been being used and the performance is verified.