Three-point or four-point bending fatigue test fixture for living rat ulna

Abstract

The invention discloses a three-point or four-point bending fatigue test fixture for a living rat ulna. The fixture comprises a carrying disc and a foreleg uploading test device, wherein the carrying disc is arranged in a test chamber; the foreleg uploading test device comprises an upper connecting rod, an upper spring connection shaft, a linear elastic spring, a lower spring connection shaft, a T-shaped upper pressure head slide carriage, upper pressure heads, lower support heads, a C-shaped lower slide carriage and a lower connecting rod; the C-shaped lower slide carriage is mounted on the lower connecting rod connected with a main engine load sensor, and the upper end of the C-shaped lower slide carriage is provided with at least two guide pillars; a linear bearing capable of enabling the T-shaped upper pressure head slide carriage to move up and down along the guide pillars is mounted on the T-shaped upper pressure head slide carriage, the top of the T-shaped upper pressure head slide carriage is provided with the lower spring connection shaft connected with the lower end of the linear elastic spring, the upper end of the linear elastic spring is mounted on the lower end of the upper spring connection shaft, and the upper spring connection shaft is mounted at the lower end of the upper connecting rod; and one or more upper pressure heads are arranged under the T-shaped upper pressure head slide carriage, two lower support heads are arranged on the C-shaped lower slide carriage corresponding to the lower part of the upper pressure heads, and the carrying disc is mounted under the lower support heads. The fixture provided by the invention can take a living rat as a carrier, and is simple in structure, convenient to use, precise in acting points, accurate in location and more excellent in microdamage research, thereby being suitable for performing the three-point or four-point bending fatigue test on the living rat ulna.

Description

technical field [0001] The invention relates to a clamping mechanism, in particular to a clamp for three-point or four-point bending fatigue test of living mouse ulna. Background technique [0002] The measurement of mechanical parameters of bone loading in live experimental mice is the basic research to establish related theories and practical applications of bone mechanics, and the ulna clamping mechanism of living experimental mice is used for clamping, and the dynamic and static loading experiments are carried out on the ulna on the mechanical experiment equipment. It can test the load-strain mechanical parameters of the ulna of experimental mice under different load conditions, and draw the stress-strain curve of the ulna. At the same time, it can further analyze and study various loads on the fatigue micro-damage of the ulnar bone tissue of experimental mice, and provide a basis for related theoretical research on bone mechanics, bone tissue engineering, pathology, and...

AI Technical Summary

Problems solved by technology

[0003] At present, the bone loading mechanics experiment of living rats mainly adopts two kinds of axial compression and four-point bending fatigue tests. At home and abroad, most of them use axial compression fatigue methods to obtain specimen micro-damages and fatigue fractures. For example, the Chinese patent, the patent number is: CN200910197437.8, the patent name is: the patent of the axial loading and clamping mechanism of the ulna of living experimental mice, which adopts a method of axial loading and compression of the ulna of living experimental mice, but the point of application of axial compression is often unclear, and micro damage The position is not easy to determine; while the four-point bending fatigue positioning is accurate, the tension force point caused by the deformation is clear, and obvious micro-damages and stress fractures can occur, which makes up for the unclear tension force point and micro-damages caused by axial compression deformation. However, there is no clamping device for four-point bending test at present, especially there is no four-point bending test device for the living body, and the four-point bending test requires that between two upper pressure points Pure bending force is generated, while the shearing force is zero, and the strength at each pressure point must be equal, which is technically difficult, especially for live rats without special fixtures, so the test is difficult

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