BBB-080

The Ball Bar Box (BBB) is a 2D contour measuring system and is designed for measuring the dynamic motion of the machine tools which are used for drilling or cutting the small shapes on the products like lens hole、ear phone hole、speaker hole etc... To get the finest surface, parameters of the servo controller must be tuned before machining. The results of tuning have to be judged depend the real motion of the machine tool. At currently time, there is no fast-installing measuring instrument to perform this kind of measurement.

BBB is a 2D contour measuring system using two optical scale ball bars. After installing two ball bars on the table of a machine tool, the CNC controller drives the table to move relative to the tool on a 2D plane according to a NC test program. The BBB system measures the lengths of the two ball bars and computes the actual positions of the tool. After the measurement, the dynamic motion errors of the machine tool can be obtained by comparing the actual contour and the ideal testing paths.

Ball Bar Box contain two optical scale ball bars and accessories like two fixable pivot assemblies、one center rod、one extension rod、one L-shaped block、one counterweighting block.

BBB uses two fixable pivot assemblies to define two points as P1、P2 in the figure.The two points define a hypotenuse of the triangle. Then BBB uses the ball bar B with an extension rod to measure the length of the hypotenuse, noted as L3. After that, the extension rod is removed and a L-shaped block is mounted on the ball bar B. Then the two ball bars A and B form the two short sides of the triangle. The center rod is installed on the main spindle with a precision ball at its end, which is the measured point, noted as P3.

Because ball bar B contains a L-Shaped Block, two ball bars won't interfere with each other during the motion. Via L1、L2、L3, BBB can use trilateration method to obtain the real position of measured point.

LEI & SO provides different lengths of optical scale ball bar. One single ball bar can use for measurement of distance between two points in one dimension.