A slider-type cross-section full-support mandrel structure with ratchet backstop rotation and diameter reduction

Abstract

The invention discloses a slider-type cross-section full-support mandrel structure with backstop rotation and diameter reduction of a ratchet wheel. It includes a mandrel joint and a straight handle, and the mandrel joint and the straight handle are connected by a quick-release universal joint. The rotating shaft of the mandrel joint is sequentially equipped with a connecting rod mounting plate, a ratchet, a reverse ratchet, a bearing, and a limiter. Position snap ring, the outer ring of the bearing is equipped with a pawl mounting frame, the connecting rod mounting plate and the pawl mounting frame are respectively hinged with the long and short connecting rods, and the long and short connecting rods are hinged with the slider parts of the outer ring; through the pawl mounting frame The relative rotation with the rotating shaft drives the movement of the connecting rod mechanism, and pushes the movement of the slider part to achieve diameter reduction. The diameter becomes smaller when the ratchet device is used to limit the use; the slider part consists of two layers of arc-shaped blocks. Block locating pin, one layer is provided with slide block locating pin chute. The mandrel rod diameter of the invention can be adjusted to meet the processing needs of circular cross-section pipes of different sizes, and the adjustment process is simple and fast, which can save production costs and improve efficiency.

Description

technical field [0001] The invention belongs to the technical field of preventing wrinkling and cross-section flattening distortion defects of a circular cross-section tube, and in particular relates to a slider-type cross-section full-support mandrel structure with a ratchet backstop rotation and diameter reduction. Background technique [0002] Circular cross-section elbow has the characteristics of hollow cross-section, light weight, low consumption and high efficiency, etc., and is widely used in aerospace, shipbuilding and automobile industries. The forming process of complex bent pipes (such as thin wall, large diameter, large bending angle, etc.) often has defects such as wrinkling, cross-section flattening and distortion, etc. Inserting a mandrel into the billet to be bent can effectively reduce the wrinkling in the forming process of the bent pipe and cross-section flattening distortion, so the study of the structure and performance of the mandrel has great signific...

AI Technical Summary

Problems solved by technology

[0004] The existing mandrels mainly have the following deficiencies: (1) The mandrels used in actual production have a fixed radial size. If pipe fittings with different diameters need to be bent, mandrels with corresponding sizes are required, resulting in the production cost of the bent pipe, the mandrel storage costs are high

(2) In response to the problems mentioned in (1), many people have proposed schemes to realize mandrel diameter reduction. These schemes generally have two problems. The outer contour of the mandrel is no longer a complete circle, but there is a gap, which weakens the support effect of the mandrel; second, the process of diameter adjustment and fixing is complicated, and the joints need to be removed one by one for adjustment. Re-install and disassemble the limit lock nut, collar and other components, which reduces the use efficiency of the mandrel

(3) The joints of multi-section flexible mandrels are often connected by hinges or ball joints. A hinge with only one degree of freedom will limit the direction of use of the mandrel, resulting in uneven wear of the mandrel and shortening the service life; the assembly of the ball joint and It is difficult to disassemble, and it is extremely inconvenient to add or remove joints according to changing bending parameters

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