Adjustable hydraulic expansion mandrel and method

Abstract

The invention belongs to the technical field of precision machining and testing, and discloses an adjustable hydraulic expansion mandrel and a method. The adjustable hydraulic expansion mandrel comprises an expansion mandrel, a compensation ring, a workpiece, a dense ball shaft sleeve, a gasket, a cross-shaped gasket, a locking nut, an adjusting ring, a set screw, a connecting screw, a pressurizing screw, an exhaust screw and a rotary main shaft. The expansion mandrel is provided with a mandrel positioning face, an adjusting face, a workpiece positioning face, an expansion shaft section, finethreads, a center hole, a pressurizing screw hole and an exhaust screw hole. The radial position of the expansion mandrel is adjusted through the adjusting ring and the set screw; the compensation ring is used for determining the axial position of the workpiece and compensating the end face run-out error of the positioning surface of the workpiece; no mounting clearance exists in a workpiece innerhole through expansion of the expansion shaft section; the positioning precision of the workpiece is improved through the micro interference and error homogenization effect of the dense ball shaft sleeve; the expansion mandrel of the same specification achieves positioning of workpieces with different hole diameters by installing dense ball shaft sleeves of different ball diameters, and good market application prospects and popularization value are achieved.

Description

technical field [0001] The invention belongs to the technical field of precision machining and testing, and relates to an adjustable hydraulic expansion mandrel and a method. Background technique [0002] Using the rotary motion of the workpiece to process and test the workpiece is one of the commonly used methods in the field of precision machining and testing technology. During processing and testing, the workpiece is usually installed on the mandrel, and then the mandrel is installed on the machine tool or measuring instrument. , but considering the roundness error and cylindricity error of the inner hole and the mandrel, there is often a gap between the inner hole and the mandrel of the workpiece during installation. The expansion mandrel clamps the workpiece through expansion, and the clamping force and clamping accuracy are extremely high. Under the balanced pressure, the expansion sleeve can expand or contract evenly along the geometric axis; in the case of clamping, ...

AI Technical Summary

Problems solved by technology

These published patents all use the central hole as a reference or use chucks and flanges to fix the expansion mandrel. Although the gapless positioning of the inner hole of the workpiece can be realized, the positioning accuracy depends on the accuracy of the center hole of the expansion mandrel and the corresponding position. There is still room for improvement in the precision of the top-notch, the manufacturing precision of the mandrel itself, the expansion precision of the mandrel, and the precision of the inner hole of the workpiece.

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