A self-balancing biaxial tensile test device driven by a single motor

Abstract

The invention provides a self-balancing biaxial tension testing device driven by a single motor. The self-balancing biaxial tension testing device comprises a main framework, which is composed of a fixed bottom plate and a support. A bearing seat for fixing two sets of gear shafts is arranged on the fixed bottom plate. The gear shaft set on the left side is used to connect a bevel gear transmission device of a power input part, and the gear shaft set on the right side is used to connect a central gear set of a stretch loading part. The bevel gear transmission device is driven by a motor to drive two gear shafts (I) to rotate in opposite directions; the transmission large gear on the left side is driven to rotate in an opposite direction, the transmission large gear on the right side is driven to rotate in an opposite direction; under a work state, two sets of central gears rotate in opposite directions, the racks engaged with the central gears and interlinked clamps are driven to slideoutwards along a guide groove arranged in the support so as to stretch a test piece biaxially, and stress-strain data is obtained during the test process. The structure is simple, and the device is convenient to use, is practical and economic, and can reduce the test error.

Description

technical field [0001] The invention relates to the technical field of material mechanics and performance test research, in particular to a self-balancing bidirectional tensile test device driven by a single motor. Background technique [0002] Since the plate and shell theory was founded, its theory has been continuously developed and improved, and it is widely used in aerospace, automobile and other fields. The stress state of most plates is a two-way stress state. However, the current exploration and detection of the formability of sheet metal still use uniaxial tensile test to evaluate it qualitatively in most cases, and uniaxial tensile test cannot simultaneously detect the thickness of the sheet under linear or nonlinear loading paths in different directions. The elasto-plastic forming characteristics and fracture law, so its defects are very obvious, and cannot meet the experimental requirements for the exploration and testing of the forming properties of automobile s...

AI Technical Summary

Problems solved by technology

Among them, the hydraulic test device needs an additional closed-loop control system, and the variable loading ratio must be realized, resulting in a relatively complicated structure and high cost; there are also some special large-scale equipment in the mechanical two-way tensile test device, and its cost is relatively high. High; relatively simple mechanical biaxial tensile test devices are discussed here, some of which can even be directly applied on universal testing machines, but all have defects of varying degrees

For example, the Chinese patent (application number is 87205653) mechanical bidirectional tensile tester discloses a test device that utilizes structures such as a universal head, a buffer spring and a hinge to test the bidirectional tensile properties of a plate, but this The experimental device cannot guarantee the same strain rate during the working process, and its buffer spring will also cause the data measured by the tension and pressure sensor to be too small; Chinese patent (application number 201010240086) mechanical bidirectional tensile tester with variable ratio loading , discloses a structure that utilizes an inverted quadrangular truss slanted slider, a slanted strut, a tension-compression sensor, and a chuck to realize a bidirectional tensile test on a plate under different loading ratios, and the strain rate can be kept constant, but because The included angle between the diagonal strut and the horizontal plane of the device needs to be within a limited range of angles, and the angle range of the inclined plane of the inverted quadrangular platform oblique slider is also limited, so the range of variable loading ratio is limited, and the loading stroke The scope is also limited; in addition, the Chinese patent (application number is 201710623586) a rack-and-pinion universal testing machine variable loading ratio bidirectional tensile test device discloses a gear structure using sun gears, planetary gears and gears The rack-and-pinion fixture and other mechanisms realize the bidirectional tensile test with variable ratio loading, but the rack-and-pinion mechanism will generate additional bending moments and increase friction, thus affecting the experimental results

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