CN104014831A - Method and clamp for clamping thin-walled cylinder-shaped workpieces - Google Patents

Abstract

A clamping method and fixture for a thin-walled cylindrical workpiece, comprising an airbag 2, polyurethane rubber 3, a connecting pipe 4, a mandrel 5, an inner nut cover plate 7 and an outer nut cover plate 8, through the airbag 2, polyurethane rubber 3 Radial elastic deformation, as well as the holding force of the connecting pipe 4, the inner nut cover plate 7, and the outer nut cover plate 8, realize the uniform clamping of thin-walled cylindrical workpieces; Installed on the mandrel 5, then tighten the inner nut cover plate 7 first, then install the outer nut cover plate 8 and tighten it, so as to realize the assembly of the thin-walled cylindrical workpiece holding fixture.

Description

Clamping method and fixture for thin-walled cylindrical workpiece

Technical field

The invention provides a clamping method and a clamp for a thin-walled cylindrical workpiece, and relates to the technical field of mechanical design.

Background technique

At present, when finishing thin-walled cylindrical workpieces such as inner hole grinding and turning, radial clamping with an elastic sleeve attached to the outer circle of the workpiece or clamping with a three-jaw chuck is generally used to fix the workpiece, which is easy to produce The clamping is deformed, the processing accuracy is difficult to guarantee, and the production efficiency is low.

Contents of the invention

The invention provides a clamping method and a clamp for a thin-walled cylindrical workpiece. The fixture is composed of air bag 2, polyurethane rubber 3, connecting pipe 4, mandrel 5, inner nut cover plate 7 and outer nut cover plate 8.

Install the connecting pipe 4 and the air bag 2 on the mandrel successively, and then put the polyurethane rubber 3 on the air bag. produce stress concentrations. The workpiece 6 is set on the rubber sleeve again, and now the outer diameter of the rubber sleeve is smaller than the inner diameter of the workpiece, and the total length of the rubber sleeve is slightly less than the actual length of the workpiece. Screw the left and right, inner and outer nut cover plates 7 and 8 to the position just in contact with the rubber sleeve respectively. After the inflation is completed, the workpiece can be fully and evenly clamped.

The features of this fixture are:

1. The jig can provide any part of the workpiece that can be reliably supported from the inner peripheral surface side without omission, and can exert a firm holding force that is not inferior to the processing pressure, and it is difficult to apply a strong processing force even if it is locally applied. Deformation, capable of high-precision machining;

2. Polyurethane rubber not only has the property of fluid flow in all directions, but also has a certain hardness and rigidity like a rigid body, will not flow, has good wear resistance, high strength, good elasticity, aging resistance, and good oil resistance;

3. The circumferential preload can be applied to the outer ring of the rubber sleeve to prevent the workpiece from vibrating during processing.

Description of drawings

Fig. 1 is a front view of a thin-walled cylindrical workpiece holding jig.

Fig. 2 is a three-dimensional view of a thin-walled cylindrical workpiece holding jig.

Fig. 3 is a cross-sectional view of a thin-walled cylindrical workpiece holding jig.

Detailed ways

Tighten the inner nut cover plate 7 with a small force so that there is no gap between each section of the rubber sleeve, and then tighten the outer nut cover plate 8 with the same force. The outer diameter of the outer nut cover plate 8 is slightly smaller than the workpiece 6 inner diameter. At this time, the air bag 2 is inflated through the air hole 1 at the end of the mandrel 5, and the air bag 2 expands so that the polyurethane rubber 3 elastically deforms outward along the diameter of the mandrel, and is inflated to clamp the workpiece. The roughness of the contact part between the outer nut cover plate 8 and the rubber is relatively high. At this time, tighten the outer nut cover plate 8 with greater force to apply a pre-tightening force to the rubber sleeve to drive the outer ring of the rubber sleeve to rotate at a certain angle to prevent the workpiece from being processed. tremors. The screw thread of mandrel 5 left half is opposite to the screw thread of right half, and the direction of rotation of mandrel 5 when left and right, inner and outer nut cover plates 7,8 tightening direction is opposite with turning. After the processing is finished, unscrew the left and right outer nut cover plates 8 earlier, and then discharge the air in the air bag 2.

The present invention has been disclosed above with preferred implementations, but it is not intended to limit the present invention. All technical solutions obtained by adopting equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims (4)

1. A clamping method and fixture for a thin-walled cylindrical workpiece, comprising an air bag 2, polyurethane rubber 3, a connecting pipe 4, a mandrel 5, an inner nut cover plate 7 and an outer nut cover plate 8, through which the air bag 2, polyurethane rubber The radial elastic deformation of 3, and the holding force of connecting pipe 4, inner nut cover plate 7, and outer nut cover plate 8, realize uniform clamping of thin-walled cylindrical workpieces; it is characterized in that connecting pipe 4, air bag 2, polyurethane The rubber 3 is installed on the mandrel 5, and then the inner nut cover plate 7 is first tightened, and then the outer nut cover plate 8 is installed and tightened to realize the assembly of the thin-walled cylindrical workpiece holding fixture. 2. The holding fixture for thin-walled cylindrical workpieces according to claim 1, characterized in that the first and last two polyurethane rubbers need to be made into skirts to prevent the airbag from rupturing when the air pressure increases. 3. The holding fixture for thin-walled cylindrical workpiece according to claim 1, characterized in that threads need to be made on the mandrel, the left half of the mandrel is opposite to the right half of the thread, and the left and right ends are covered with inner and outer nuts The direction of plate tightening is opposite to the direction of rotation of the mandrel during turning. 4. The holding fixture for thin-walled cylindrical workpieces according to claim 1, 2, 3, characterized in that a through hole needs to be made inside the mandrel to facilitate the inflation of the airbag.