CN210426420U

CN210426420U - Radial deformation measuring device based on LVDT sensor

Info

Publication number: CN210426420U
Application number: CN201921412078.9U
Authority: CN
Inventors: 袁洪魏; 唐维; 董天宝; 赵龙; 颜熹琳
Original assignee: Institute of Chemical Material of CAEP
Current assignee: Institute of Chemical Material of CAEP
Priority date: 2019-08-28
Filing date: 2019-08-28
Publication date: 2020-04-28
Anticipated expiration: 2029-08-28

Abstract

The utility model discloses a radial deformation measuring device based on LVDT sensor, including auxiliary fixtures and sensor device, sensor device includes flexible iron wire, LVDT coil, LVDT iron core, spring and bolt, the sample is fixed between flexible iron wire and auxiliary fixtures, and the one end connecting bolt of flexible iron wire is fixed in one side of auxiliary fixtures, and the other end of flexible iron wire establishes ties with spring and LVDT iron core in proper order to the LVDT coil has been alternated, the LVDT coil is fixed auxiliary fixtures's opposite side. The device is simple to assemble, can effectively amplify radial deformation values, improves measurement accuracy, and measures the circumferential strain of the explosive under the condition of not influencing the explosive test.

Description

Radial deformation measuring device based on LVDT sensor

Technical Field

The utility model relates to a mechanical properties of materials technical field, concretely relates to radial deformation measuring device based on LVDT sensor.

Background

In the mechanical property test of the material, including stretching, compression, confining pressure stretching, confining pressure compression and the like, the axial deformation and the radial deformation of the material need to be accurately measured so as to accurately evaluate the mechanical property of the material and construct a mechanical model, and the measurement of the radial deformation is an important test content for measuring the mechanical property of the explosive. Compared with axial deformation, the radial deformation test is difficult to accurately measure due to the factors of small gauge length, small deformation and the like. The existing radial test method is divided into three methods, firstly, measurement is carried out based on a strain gauge, but point strain rather than global average strain is obtained, and great singularity exists; secondly, the digital speckle technology is adopted to measure the full-field deformation of the sample in the test process, but the measurement precision is greatly limited, the application to small deformation measurement is difficult, and the cost of the test equipment is high; thirdly, the radial symmetric LVDT sensor is adopted for measurement, but the centering and fixing of the sample are very difficult, the length of the gauge length is only the diameter length of the sample, and the gauge length is too short, so that accurate deformation data is difficult to obtain.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the utility model provides a radial deformation measuring device based on LVDT sensor, the device assembly is simple, can effectively enlarge radial deformation numerical value, improves measurement accuracy, surveys its hoop and meets an emergency under the condition that does not influence the explosive test.

In order to achieve the technical effect, the utility model provides a following technical scheme:

the utility model provides a radial deformation measuring device based on LVDT sensor, includes auxiliary fixtures and sensor device, the sensor device includes flexible iron wire, LVDT coil, LVDT iron core, spring and bolt, and the sample is fixed between flexible iron wire and auxiliary fixtures, and the one end connecting bolt of flexible iron wire is fixed in one side of auxiliary fixtures, and the other end of flexible iron wire establishes ties with spring and LVDT iron core in proper order to alternate the LVDT coil, the LVDT coil is fixed the opposite side of auxiliary fixtures.

A further technical scheme is that one side of the auxiliary tool is provided with a U-shaped notch for fixing a bolt, and the other end of the auxiliary tool is provided with a cylindrical hole for fixing the LVDT coil.

A further technical scheme is that one side of the auxiliary tool, which is in contact with the sample, is of a V-shaped structure, and the sample is fixed at a groove of the V-shaped structure.

The utility model discloses high resolution based on LVDT sensor reequips it, amplifies the radial deformation of sample through the change of the flexible iron wire effective length who encircles the sample. When the radial change of the sample occurs, the flexible iron wire is driven to change, and further the contraction or the extension of the spring is caused, so that the LVDT iron core moves in the LVDT coil and is sensed and measured by the LVDT.

The deformation displacement directly measured by the test is delta L, and the radial strain calculation formula

In the formula: ε is the radial strain in mm/mm; Δ L is displacement measured by the LVDT sensor in mm; d is the sample diameter in mm. And (4) calculating according to the formula (1) to obtain the radial strain of the test sample.

Compared with the prior art, the utility model discloses following beneficial effect has: the device can effectively warp jointly according to the sample to simple structure, the clamping is convenient, and has exerted LVDT sensor's high accuracy, and an important highlight of the device lies in increasing the gauge length of radial strain test to (pi +2) D by diameter D, and the gauge length has increased 157%, has further promoted measurement accuracy. The device can be widely applied to the measurement of radial small deformation of materials in the situations of stretching, compression and confining pressure.

Drawings

FIG. 1 is a schematic view of the overall structure of the device of the present invention;

FIG. 2 is a top cross-sectional view of the inventive apparatus;

fig. 3 is a schematic structural view of the auxiliary tool of the present invention;

fig. 4 is a schematic connection diagram of the LVDT sensor according to the present invention.

The device comprises a test sample 1, a flexible iron wire 2, an auxiliary tool 3, a 4-LVDT coil, a 5-LVDT iron core, a 6-bolt and a 7-spring.

Detailed Description

The invention will be further explained and explained with reference to the drawings and the embodiments.

As shown in fig. 1 and 2, the utility model provides a radial deformation measuring device based on LVDT sensor, including sample 1, auxiliary fixtures 3 and sensor device, sensor device includes flexible iron wire 2, LVDT coil 4, LVDT iron core 5, spring 7 and bolt 6, sample 1 is fixed between flexible iron wire 2 and auxiliary fixtures 3, and the one end connecting bolt 6 of flexible iron wire 2 is fixed in one side of auxiliary fixtures 3, and the other end of flexible iron wire 2 establishes ties with spring 7 and LVDT iron core 5 in proper order to alternate LVDT coil 4, LVDT coil 4 is fixed the opposite side of auxiliary fixtures 3. And one side of the auxiliary tool 3 is provided with a U-shaped notch for fixing the bolt 6, and the other end of the auxiliary tool is provided with a cylindrical hole for fixing the LVDT coil 4. One side that auxiliary fixtures and sample contacted is V style of calligraphy structure, the sample is fixed in the groove of V style of calligraphy structure.

During the installation, at first be fixed in auxiliary fixtures's cylindrical hole department with the LVDT coil, establish ties LVDT iron core, flexible iron wire, spring to alternate the LVDT coil through auxiliary fixtures, walk around the experiment sample with the iron wire and be fixed in auxiliary fixtures opposite side breach department at other end connecting bolt. The contraction degree of the spring is controlled through the adjusting bolt, so that stable clamping of the tool and arrangement of the LVDT sensor in a measuring range are achieved.

In the radial deformation process of a test sample, the flexible iron wire drives the elasticity to shorten or extend along with the radial deformation of the test sample, the relative position of the LVDT iron core and the coil is further changed, and the radial strain of the test sample is calculated by a formula by reading the displacement reading of the LVDT sensor and combining the diameter information of the test sample.

It is to be understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principles of the present invention, and the present invention is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements (e.g., changes in feature size, etc.) can be made without departing from the spirit and scope of the invention.

Claims

1. The utility model provides a radial deformation measuring device based on LVDT sensor, its characterized in that, includes auxiliary fixtures and sensor device, the sensor device includes flexible iron wire, LVDT coil, LVDT iron core, spring and bolt, and the sample is fixed between flexible iron wire and auxiliary fixtures, and the one end connecting bolt of flexible iron wire is fixed in one side of auxiliary fixtures, and the other end of flexible iron wire is established ties with spring and LVDT iron core in proper order to alternate the LVDT coil, the LVDT coil is fixed the opposite side of auxiliary fixtures.

2. The LVDT sensor-based radial deformation measuring device according to claim 1, wherein the auxiliary tool is provided with a U-shaped notch on one side for fixing the bolt and a cylindrical hole on the other side for fixing the LVDT coil.

3. The LVDT sensor-based radial deformation measuring device according to claim 1, wherein the auxiliary tool has a V-shaped structure on the side contacting the test sample, and the test sample is fixed on the groove of the V-shaped structure.