Strain gauge assembly detection device and thermal imaging detection system

Abstract

The present invention provides a strain gauge assembly detection device and a thermal imaging detection system. The strain gauge assembly detection device includes a base, a thermal imaging device, a product bearing seat and a marking pen. The base is provided with a detection chamber, and a slide rail extending in the horizontal direction is provided in the detection chamber. The thermal imaging device includes an infrared lens. The product bearing seat can move along the extension direction of the slide rail. A strain gauge assembly installation position is provided on the product bearing seat. The infrared lens is located above the strain gauge assembly installation position. A reference grid wire electrical connection line and a measurement grid wire electrical connection line are also provided on the product bearing seat. The marking pen is located above the strain gauge assembly installation position. The strain gauge assembly detection device can realize automatic detection of the quality of the strain gauge assembly.

Description

Technical Field

[0001] The present invention relates to the technical field of strain gauge assembly detection devices, and in particular to a strain gauge assembly detection device and a thermal imaging detection system using thermal imaging technology. Background Art

[0002] The grid stress variable balance of the strain gauge is a key factor in the life of the strain gauge. In the production process of the strain gauge, in order to accurately adjust the grid resistance, the copper layer will be uneven in thickness during grinding, resulting in local stress concentration. At the same time, the thickness of the thermal conductive adhesive layer on the bottom of the substrate is different, which will also cause local stress concentration, resulting in local metal fatigue failure, which will affect the service life of the strain gauge. There is currently no device that can detect the quality of strain gauge components, and manual screening is impossible. Summary of the invention

[0003] A first object of the present invention is to provide a strain gauge assembly detection device capable of automatically detecting the quality of a strain gauge assembly.

[0004] A second object of the present invention is to provide a thermal imaging detection system having the above strain gauge assembly detection device.

[0005] To achieve the above-mentioned purpose, the present invention provides a strain gauge assembly detection device, including a base, a thermal imaging device, a product bearing seat and a marking pen, wherein a detection chamber is arranged on the base, a slide rail extending in the horizontal direction is arranged in the detection chamber, the thermal imaging device includes an infrared lens, the product bearing seat can move along the extension direction of the slide rail, a strain gauge assembly installation position is arranged on the product bearing seat, the infrared lens is located above the strain gauge assembly installation position, and a reference grid wire electrical connection line and a measurement grid wire electrical connection line are also arranged on the product bearing seat. The marking pen is located above the strain gauge assembly installation position.

[0006] It can be seen from the above scheme that when testing the strain gauge assembly, the strain gauge assembly is installed on the strain gauge assembly installation position, the reference grid wire is electrically connected to the reference grid wire electrical connection line, and the measuring grid wire is electrically connected to the measuring grid wire electrical connection line. After power is turned on, the infrared lens collects the infrared thermal imaging images of the reference grid wire and the measuring grid wire and feeds them back to the controller, which compares them with the preset image. The controller controls the movement of the marking pen and marks according to the comparison result. The detection device can realize automatic detection of the quality of the strain gauge assembly, and distinguish and mark the strain gauge assemblies with good quality and poor quality. The strain gauge assembly detection device can realize automatic detection of the quality of the strain gauge assembly.

[0007] A preferred solution is that the detection device further includes a temperature regulating component, which is arranged on the outer wall of the detection chamber, and the detection chamber has a detection space with constant temperature and humidity.

[0008] It can be seen that the temperature regulating component controls the temperature of the product support seat and the detection chamber, so that the detection chamber and the product support seat are kept at a constant temperature.

[0009] A preferred solution is that the product bearing seat includes a first clamping plate and a second clamping plate stacked up and down. A first clearance groove is provided on the first clamping plate, and the first clearance groove penetrates the first clamping plate in the vertical direction. A second clearance groove is provided on the second clamping plate, and the second clearance groove penetrates the second clamping plate in the vertical direction. The first clearance groove and the second clearance groove are arranged opposite to each other in the vertical direction. The strain gauge assembly installation position is located between the first clamping plate and the second clamping plate, and the projections of the first clearance groove and the second clearance groove along the vertical direction are both located within the projection of the strain gauge assembly installation position along the vertical direction.

[0010] It can be seen that when the strain gauge assembly is installed to the strain gauge assembly installation position, the first clamping plate and the second clamping plate clamp the strain gauge assembly at the circumferential edge position of the strain gauge assembly, and the reference grid and the measuring grid leak out from the first make way groove and correspond to the second make way groove in the vertical direction. In this way, the side of the strain gauge assembly opposite to the reference grid and the measuring grid does not contact the product bearing seat, which can minimize the influence of the external environment on the measurement results.

[0011] A preferred solution is that the extension direction of the reference grid wire electrical connection line is parallel to the extension direction of the slide rail, and a plurality of first electrical connection points are arranged on the reference grid wire electrical connection line. The plurality of first electrical connection points are arranged along the length direction of the reference grid wire electrical connection line, and a first electrical connection point is arranged corresponding to a strain gauge assembly installation position.

[0012] It can be seen that the reference grid wire of a strain gauge assembly is connected to a first electrical connection point.

[0013] A preferred solution is that the extension direction of the measuring grid wire electrical connection line is parallel to the extension direction of the slide rail, and a plurality of second electrical connection points are arranged on the measuring grid wire electrical connection line. The plurality of second electrical connection points are arranged along the length direction of the measuring grid wire electrical connection line, and a second electrical connection point is arranged opposite to a strain gauge assembly mounting position.

[0014] It can be seen that the measuring grid wires of a strain gauge arrangement are connected to a second electrical connection point.

[0015] A preferred solution is that there are multiple strain gauge assembly installation positions, and the multiple strain gauge assembly installation positions are arranged in a matrix of two rows and multiple columns.

[0016] It can be seen that the detection efficiency can be improved by simultaneously detecting multiple strain gauge assemblies.

[0017] A further solution is that the reference grid wire electrical connection line and the measurement grid wire electrical connection line are both located between two rows of strain gauge assembly mounting positions.

[0018] To achieve the above second objective, the present invention provides a thermal imaging detection system, including a strain gauge assembly and the above strain gauge assembly detection device, wherein the strain gauge assembly is installed on a strain gauge assembly installation position.

[0019] A preferred solution is that the strain gauge assembly includes two reference grids and two measuring grids. The two reference grids are connected in series through the reference grid wire electrical connection line, the two measuring grids are connected in series through the measuring grid wire electrical connection line, and the reference grids are connected in parallel with the measuring grids.

[0020] A preferred solution is that the strain gauge assembly includes two reference grids and two measuring grids. The number of reference grid wire electrical connection lines is two, and the number of measuring grid wire electrical connection lines is two. The two reference grids are respectively connected to the two reference grid wire electrical connection lines, and the two measuring grids are respectively connected to the two measuring grid wire electrical connection lines. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the structure of the stress sensor in the strain gauge assembly.

[0022] Figure 2 It is a schematic structural diagram of an embodiment of a thermal imaging detection system of the present invention.

[0023] Figure 3 It is a structural decomposition diagram of an embodiment of a thermal imaging detection system of the present invention.

[0024] Figure 4 yes Figure 3 A partial enlarged view of point A in the middle.

[0025] Figure 5 It is a cross-sectional view of an embodiment of a thermal imaging detection system of the present invention.

[0026] Figure 6 yes Figure 5 A partial enlarged view of point B in the middle.

[0027] Figure 7 yes Figure 6 A partial enlarged view of point C in the middle.

[0028] The invention is further described below with reference to the accompanying drawings and embodiments. DETAILED DESCRIPTION

[0029] See also Figure 1The strain gauge assembly 1 of this embodiment includes a flat substrate layer 101, a flexible circuit board 102 is arranged above the substrate layer 101, and a stress sensor is etched on the flexible circuit board 102. The stress sensor includes two reference grids 11 and two measuring grids 12 arranged in a matrix. The two reference grids 11 are located on one diagonal line, and the two measuring grids 12 are located on another diagonal line. One reference grid 11 is formed by bending a reference grid wire made of constantan wire, and one measuring grid 12 is formed by bending a measuring grid wire made of constantan wire.

[0030] See also Figures 2 to 4 The thermal imaging detection system of this embodiment includes a strain gauge assembly 1 and a strain gauge assembly detection device 2.

[0031] The strain gauge assembly detection device 2 includes a base 21 , a control device, a thermal imaging device 22 , a first driving component (not shown), a product supporting seat 23 , a temperature adjustment component 24 , a height adjustment component 26 , a second driving component (not shown) and a marking pen 25 .

[0032] The base 21 is provided with a detection chamber 211, and a slide rail 212 extending in the horizontal direction is provided in the detection chamber 211. The first driving component drives the product bearing seat 23 to move along the extension direction of the slide rail 212. The first driving component is a cylinder. The base 21 is also provided with a fixing rod 213 extending in the vertical direction. The thermal imaging device 22 is mounted on the fixing rod 213 through a height adjustment component 26, so as to adjust the height of the thermal imaging device 22 in the vertical direction. The height adjustment component 26 includes a first fixing portion 261, a second fixing portion 262 and an adjusting knob 263. The thermal imaging device 22 is fixed to the first fixing portion 261, and the second fixing portion 262 is mounted on the fixing rod 213. The adjusting knob 263 passes through the second fixing portion 262 and abuts against the fixing rod 213.

[0033] The thermal imaging device 22 includes an infrared lens 221. The top of the detection chamber 211 has a light outlet 210. The infrared lens 221 is arranged downward and abuts against the light outlet 210. The infrared lens 221 is used to collect infrared light generated after the strain gauge assembly 1 is powered on. The thermal imaging device 22 can be a thermal imager.

[0034] The product support seat 23 is provided with a strain gauge assembly installation position 231, and the number of the strain gauge assembly installation positions 231 is multiple, and the multiple strain gauge assembly installation positions 231 are arranged in a matrix of two rows and multiple columns. The strain gauge assembly 1 is installed on the strain gauge assembly installation position 231, and the infrared lens 221 is located above the strain gauge assembly installation position 231.

[0035] See also Figures 5 to 7The product bearing seat 23 includes a first clamping plate 234 and a second clamping plate 235 stacked up and down. The first clamping plate 234 is provided with two rows of first give-way grooves 2341, and the first give-way grooves 2341 penetrate the first clamping plate 234 in the vertical direction. The second clamping plate 235 is provided with two rows of second give-way grooves 2351, and the second give-way grooves 2351 penetrate the second clamping plate 235 in the vertical direction. The first give-way grooves 2341 and the second give-way grooves 2351 are arranged opposite to each other in the vertical direction. The strain gauge assembly installation position 231 is located between the first clamping plate 234 and the second clamping plate 235, and the projections of the first give-way grooves 2341 and the second give-way grooves 2351 along the vertical direction are both located within the projection of the strain gauge assembly installation position 231 along the vertical direction. In this way, the periphery of the strain gauge assembly 1 is clamped by the first clamping plate 234 and the second clamping plate 235, while the reference grid 11 and the measuring grid 12 are exposed from the first clearance groove 2341, and at the same time, the side of the strain gauge assembly 1 opposite to the reference grid 11 is exposed from the second clearance groove 2351, so as to minimize the influence of the external environment on the measurement result.

[0036] like Figure 3 and Figure 4 As shown, the second clamping plate 235 is also provided with a reference grid wire electrical connection line 232 and a measuring grid wire electrical connection line 233. The reference grid wire electrical connection line 232 and the measuring grid wire electrical connection line 233 are both located between two rows of strain gauge assembly mounting positions 231. The extension direction of the reference grid wire electrical connection line 232 and the extension direction of the measuring grid wire electrical connection line 233 are both parallel to the extension direction of the slide rail 212. The two reference grids 11 of each strain gauge assembly 1 are connected in series through the reference grid wire electrical connection line 232, and the reference grids 11 of each strain gauge assembly are connected in series through the reference grid wire electrical connection line 232. The two measuring grids 12 of each strain gauge assembly 1 are connected in series through the measuring grid wire electrical connection line 233, and the measuring grids 12 of each strain gauge assembly are connected in series through the measuring grid wire electrical connection line 233. And the reference grid 11 is connected in parallel with the measuring grid 12.

[0037] A plurality of first electrical connection points 2321 are provided on the reference grid wire electrical connection line 232, and the plurality of first electrical connection points 2321 are arranged along the length direction of the reference grid wire electrical connection line 232. One first electrical connection point 2321 is provided corresponding to one strain gauge assembly mounting position 231, and two reference grids 11 of one strain gauge assembly 1 are both electrically connected to the first electrical connection point 2321.

[0038] A plurality of second electrical connection points 2331 are provided on the measuring grid wire electrical connection line 233, and the plurality of second electrical connection points 2331 are arranged along the length direction of the measuring grid wire electrical connection line 233. A second electrical connection point 2331 is arranged opposite to a strain gauge assembly mounting position 231, and two measuring grids 12 of a strain gauge assembly 1 are both electrically connected to the second electrical connection point 2331.

[0039] The marking pen 25 extends into the detection chamber 211, and the marking pen 25 is located above the strain gauge assembly 1, and the number of the marking pens 25 is two. One marking pen 25 marks a row of strain gauge assemblies 1. The second driving component can be a cylinder, and the cylinder pushes the marking pen 25 to move between the marking position and the non-marking position. In the marking position, the marking pen 25 contacts and marks the strain gauge assembly 1, and in the non-marking position, there is a gap between the marking pen 25 and the strain gauge assembly 1.

[0040] The temperature regulating component 24 is arranged below the base 21 and on the outer wall at the bottom of the detection chamber 211. The temperature regulating component 24 is a thermoelectric cooling sheet. The detection chamber 211 has a detection space with constant temperature and humidity and no airflow interference. At the same time, a constant current source and constant voltage are provided to the strain gauge assembly 1 through the reference grid wire electrical connection line 232 and the measurement grid wire electrical connection line 233, so that the heating state of the constantan wire of the measurement grid wire and the reference grid wire is the same, so that the unbalanced area, that is, the defective product, can be judged through the thermal imaging picture. The high temperature area is also the stress concentration area.

[0041] The working process of the strain gauge assembly detection device of the present invention is described as follows.

[0042] First, the temperature and humidity in the detection chamber 211 are kept constant, the temperature regulating component 24 regulates the temperature of the product support seat 23 to keep it at 20° C., and current is passed through the reference grid wire electrical connection line 232 and the measurement grid wire electrical connection line 233 .

[0043] Next, the infrared light generated by the strain gauge assembly 1 after being powered on is received by the photosensitive element of the thermal imaging device 22 through the infrared lens 221 , so that the thermal imaging device 22 obtains an infrared thermal image, which corresponds to the thermal distribution field of the reference grid 11 and the measuring grid 12 .

[0044] Next, the controller compares the obtained infrared thermal image with the preset infrared thermal image, and controls the second driving component to drive the marking pen 25 to move and mark the strain gauge assembly 1 with good quality according to the comparison result.

[0045] Next, the first driving component drives the product bearing seat 23 to move forward along the slide rail 212, and the second driving component drives the marking pen 25 to move and mark the strain gauge assembly 1 with good quality until the marking is completed.

[0046] In addition, the number of reference grid wire electrical connection lines can also be two, and the number of measuring grid wire electrical connection lines can be two. Two reference grids are respectively connected to the two reference grid wire electrical connection lines, and two measuring grids are respectively connected to the two measuring grid wire electrical connection lines. In this way, the two reference grids and the two measuring grids are all arranged in parallel, and each reference grid wire electrical connection line and each measuring grid wire electrical connection line can be controlled separately. Of the two marking pens, one marking pen can mark a strain gauge assembly with excellent quality, and the other marking pen can mark a strain gauge assembly with good quality. The number and installation positions of the marking pens can be changed as needed. The temperature control component can also be arranged on the outer wall of the side wall or the top wall, and its function is to maintain a constant temperature in the detection room. The infrared lens can also extend from the light outlet into the detection room. The above changes can also achieve the purpose of the present invention.

[0047] Finally, it should be emphasized that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various changes and modifications. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A strain gauge assembly detection device, characterized in that: include: A base, wherein a detection chamber is disposed on the base, and a slide rail extending in a horizontal direction is disposed in the detection chamber; A thermal imaging device, wherein the thermal imaging device comprises an infrared lens; A product bearing seat, wherein the product bearing seat can move along the extension direction of the slide rail, a strain gauge assembly installation position is provided on the product bearing seat, the infrared lens is located above the strain gauge assembly installation position, and a reference grid wire electrical connection line and a measurement grid wire electrical connection line are also provided on the product bearing seat; A marking pen, the marking pen is located above the installation position of the strain gauge assembly; The detection device further comprises a temperature regulating component, wherein the temperature regulating component is arranged on the outer wall of the detection chamber, and the detection chamber has a detection space with constant temperature and humidity; The product bearing seat comprises a first clamping plate and a second clamping plate stacked up and down; The first clamping plate is provided with a first clearance groove, and the first clearance groove passes through the first clamping plate in a vertical direction; The second clamping plate is provided with a second clearance groove, and the second clearance groove passes through the second clamping plate in the vertical direction; The first clearance groove and the second clearance groove are arranged opposite to each other in the vertical direction; The strain gauge assembly installation position is located between the first clamping plate and the second clamping plate, and the projections of the first clearance groove and the second clearance groove along the vertical direction are both located within the projection of the strain gauge assembly installation position along the vertical direction.

2. The strain gauge assembly detection device according to claim 1, characterized in that: The extension direction of the reference grid wire electrical connection line is parallel to the extension direction of the slide rail; A plurality of first electrical connection points are provided on the reference grid wire electrical connection line, and the plurality of first electrical connection points are arranged along the length direction of the reference grid wire electrical connection line, and one first electrical connection point is provided corresponding to one installation position of the strain gauge assembly.

3. The strain gauge assembly detection device according to claim 1, characterized in that: The extending direction of the measuring grid wire electrical connection line is parallel to the extending direction of the slide rail; A plurality of second electrical connection points are provided on the measuring grid wire electrical connection line, and the plurality of second electrical connection points are arranged along the length direction of the measuring grid wire electrical connection line, and one second electrical connection point is arranged opposite to one of the strain gauge assembly mounting positions.

4. The strain gauge assembly detection device according to any one of claims 1 to 3, characterized in that: There are multiple strain gauge assembly installation positions, and the multiple strain gauge assembly installation positions are arranged in a matrix of two rows and multiple columns.

5. The strain gauge assembly detection device according to claim 4, characterized in that: The reference grid wire electrical connection line and the measurement grid wire electrical connection line are both located between two rows of strain gauge assembly installation positions.

6. Thermal imaging detection system, characterized in that: It comprises a strain gauge assembly and the strain gauge assembly detection device according to any one of claims 1 to 5, wherein the strain gauge assembly is installed on the strain gauge assembly installation position.

7. The thermal imaging detection system according to claim 6, characterized in that: The strain gauge assembly includes two reference grids and two measurement grids; The two reference grids are connected in series via the reference grid wire electrical connection line, the two measuring grids are connected in series via the measuring grid wire electrical connection line, and the reference grid is connected in parallel with the measuring grid.

8. The thermal imaging detection system according to claim 6, characterized in that: The strain gauge assembly includes two reference grids and two measurement grids; The number of the reference grid wire electrical connection lines is two, and the number of the measuring grid wire electrical connection lines is two; The two reference grids are connected to the two reference grid wire electrical connection lines respectively, and the two measuring grids are connected to the two measuring grid wire electrical connection lines respectively.

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