Utility model content
The purpose of this utility model is to provide a kind of based on digitized improved elastic modulus measuring instrument, solves the problem that modulus measurement mechanism volume is excessive, Measurement sensibility is inadequate existed in prior art.
The technical scheme that the utility model adopts is, a kind of based on digitized improved elastic modulus measuring instrument, comprise base, base is provided with parallel two risers relatively, web joint is provided with between two risers, one of them riser is provided with the fixed chuck for fixing steel wire, another riser is provided with leading screw force adjustment mechanism, leading screw force adjustment mechanism comprises force adjustment handle and level and is arranged on leading screw on base, leading screw is connected with force adjustment handle, the other end of leading screw is provided with pulling force sensor, for installing steel wire to be measured between pulling force sensor and fixed chuck; Also comprise digitized measurement module, digitized measurement module comprise camera for gathering steel wire deformation data, for record and process test parameter microcontroller, for showing the LCDs of test data; Camera, pulling force sensor are all connected with microcontroller, and microcontroller is connected with LCDs.
Feature of the present utility model is also, the top of web joint is provided with meter ruler.
The S type pulling force sensor of pulling force sensor to be range be 20KG.
Comprise background light source, background light source and camera respectively at the two ends of steel wire,
Microcontroller adopts the STM32F407VGT6 chip of ST company.
Three-dimensional moving device is connected with camera.
The driving circuit of pulling force sensor is high-precision meter amplifier.
The beneficial effects of the utility model are: can solve the problem that traditional young modulus measuring device volume is excessive, Measurement sensibility is inadequate, and this digitizing modulus measuring instrument structure is simple, with low cost, measuring accuracy is high.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is described in detail.
The utility model is a kind of based on digitized improved elastic modulus measuring instrument, and structure as shown in Figure 1.
Comprise base 1, base 1 is provided with parallel two risers relatively, be provided with web joint between two risers, the top of web joint is provided with meter ruler 3; One of them riser is provided with the fixed chuck 9 for fixing steel wire, another riser is provided with leading screw force adjustment mechanism, leading screw force adjustment mechanism comprises force adjustment handle 2 and level and is arranged on leading screw 5 on base 1, leading screw 5 is connected with force adjustment handle 2, the other end of leading screw 5 is provided with pulling force sensor 10, for installing steel wire to be measured between pulling force sensor 10 and fixed chuck 9;
Digitized measurement module comprise camera 6 for gathering steel wire deformation data, for record and process test parameter microcontroller, for showing LCDs 8 and the power supply of test data.Camera 6, pulling force sensor 10 are all connected with microcontroller, and microcontroller is connected with LCDs 8.
Further, the S type pulling force sensor of pulling force sensor 10 to be ranges be 20KG.
Background light source 4 and camera 6 are respectively at the two ends of steel wire, and background light source 4 is white LED lamps, and light source 4 of must having powerful connections, because know the position of steel wire by the pixel sudden change of steel wire and background.Steel wire image must have a reasonable background, just can accurately collect the positional information of steel wire.Camera 6 not only can detect steel wire stressed after elongation, the simultaneously diameter of measuring steel wire.
Microcontroller: the STM32F407VGT6 chip adopting ST company, common ARM chip, the realization of function relies on existing programmed algorithm to realize.
Three-dimensional moving device 7 is connected with camera 6, can be adjusted the focusing of camera 6 by three-dimensional moving device 7 one aspect, and the adjustment position of steel wire in the visual field, can calibrate the measurement of whole experiment on the other hand.
Before experiment starts, we need the operation carrying out a calibration, 0.5mm is rotated by regulating upper lower knob (band micrometer caliper function), camera 6 detects the pixel of steel wire movement simultaneously, thus can obtain the ratio of a pixel and actual steel wire length.Movable knob is used for adjusting the focusing of camera 6.The initial position of knob adjustment steel wire mark on image moved left and right.
Digitized measurement module:
Camera 6 and LCDs 8 are cores of whole device, the deformation data of steel wire is gathered by camera 6, by various test parameters such as microcontroller record and process steel wire diameter, tensile elongation, tension variations, and be shown in LCDs 8 in real time, operator only need record these correlation parameters, can calculate the Young modulus of measured material.
Utilize leading screw force adjustment mechanism can change the pulling force size of steel wire easily, and no longer need heavy counterweight to change pulling force.
Pulling force sensor 10 can collect the size of pulling force suffered by current steel wire, and is presented in real time in LCDs 8.The S type pulling force sensor 10 of to be range the be 20KG that we adopt.This pulling force sensor precision is high, good stability, and degree of accuracy can to 1 gram.The driving circuit section of pulling force sensor 10 is high-precision meter amplifiers, and its enlargement factor is maximum to 60dB, and operating voltage is wide, and quiescent current is little.This chip only needs some simple external circuit elements normally to work, and circuit is simple and reliable.
A kind of course of work based on digitized improved elastic modulus measuring instrument of the utility model is,
1. with the former long L of meter ruler 3 measuring steel wire, from left side fixed chuck 9 to the distance of steel wire black designation thing.
2. regulate camera three-dimensional moving device 7, rotate the knob that left and right moves up and down, make steel wire appear at LCDs 8 centre position.Rotate the focus knob (simultaneously fine-tuning camera lens) of camera 6 again, until steel wire has an imaging clearly in LCDs 8, notice that now black designation thing can not appear in the visual field, experiment afterwards can not change focal length again.
3. push button, then rotate the spiral micrometer knob (up and down) moved up and down, rotate 0.5mm, simultaneously steel wire can move up and down at screen, and attention can not frame out scope.And then push button, this Time Controller can go out according to the position calculation of twice steel wire the quantity that steel wire moves pixel automatically, also have pixel shared by steel wire diameter, now we just can calculate the physical length of physical length corresponding to pixel and diameter, namely calibrate.Record steel wire and move pixel shared by pixel and steel wire diameter, need to use during data processing below.
4., after calibration terminates, just can start to measure, first change steel wire pulling force before measurement, allow pulling force remain on more than 2kg.Regulate three-dimensional moving device 7 to move left and right camera 6, until black designation thing appears at the edge of screen, now push button 2, controller just can carry out record and the process of data as original state.
5. rotate force adjustment handle 2, change the pulling force of steel wire gradually, push button after each change and 2 just can calculate current length variations amount, pulling force to be also presented in LCDs 8 simultaneously, and we only need the pixel after recording each tension variations to change and value of thrust.Notice that value of thrust may not exceed 15kg.
6. repeat step 5, record ten groups of data, by graphing method process data, calculate the Young modulus of measured material.
By reference to the accompanying drawings embodiment of the present utility model is explained in detail above, but the utility model is not limited to above-mentioned embodiment, in the ken that one skilled in the relevant art possesses, many variations can also be made to it.