Accurate positioning and combination mode of workpiece of straightener

The accurate positioning and detection of the workpiece of the straightener is the basis to ensure the accuracy of the straightener. The active rotation center and driven rotation center are composed of the ejector pin with precision bearing. When the shaft to be straightened is put into the V-block, the cylinder pushes the driven center of rotation so that the ejector pins of the master and slave rotating centers can clamp and tighten the shaft to be straightened. The movement of the stepping motor drives the shaft to be straightened to rotate together through the active rotation center. During the rotation process, the digital dial indicator detects the runout value, and records the corresponding phase by the step number of the stepping motor, and judges the large bending amount and position of the shaft to be straightened according to the detection results.

When the straightener is running, when the workpiece is rotating, the axis of the master and slave rotation center is the measurement reference, the ejector pin and the workpiece rotate together. The surface runout value of the workpiece detected by the digital dial indicator is relative to the runout of the connecting line of the ejector hole at both ends of the workpiece. Therefore, the requirement for the rotation and runout accuracy of the ejector pin is very high, so as to ensure the repeated accuracy of the measurement.

There is no combination of displacement sensor and angle sensor to measure the runout of straightening shaft. The electronic digital dial indicator (hereinafter referred to as "digital dial indicator") produced by the straightener is used to measure the runout of straightening shaft. Its range is 0-12mm, and the resolution is 0.001mm.

Compared with the traditional measurement method of displacement sensor and angle sensor, the use of digital dial indicator greatly simplifies the hardware structure and data processing process of the system. The serial port of single-chip microcomputer communicates with the digital dial indicator directly through RS-232 bus, and reads the runout data of the digital dial indicator sample. The dial indicator completes the data acquisition and conversion processing, and the digital dial indicator is accurate 001 mm, which can fully meet the detection conditions.

During the loading process of the straightening machine, the dial indicator is used for dynamic monitoring of the straightening stroke. The difference between the runout value detected by the dial indicator and the initial value is used as the straightening stroke. Compared with the traditional way of controlling the stroke by controlling the movement of driving elements, the method of controlling the straightening stroke by real-time controlling the movement of stepping motor through the change of dial indicator data can effectively avoid the error caused by the transmission mechanism.

In order to increase the straightening range of straightening machine and make the straightening machine meet the straightening requirements of different specifications of shafts to be straightened in a certain range, the V-blocks are designed as easy to replace modules in the design process, and different specifications of V-blocks are designed for different specifications of shafts to be straightened; The position of V-block support and dial indicator support can be adjusted along the direction of the shaft to be straightened on the bottom plate according to the needs, so as to meet the straightening of shafts of different lengths.