A non-destructive testing device for the local conductivity of foam

Abstract

This utility model provides a non-destructive testing device for the local conductivity of foam, relating to the field of foam conductivity testing technology. It includes a support plate with four threaded grooves at both ends and a support frame fixedly mounted on the upper end of the support plate. By removing the sample platform when conductive adhesive or other materials fall onto it, the device allows for timely cleaning of debris. After each foam conductivity test, the sample platform is cleaned to facilitate subsequent testing. Residual conductive materials can interfere with subsequent tests, leading to false positives (misjudged as conductive) or data deviations. This invention solves the problem that foam on the sample platform requires conductivity testing, but conductive adhesive or other materials adhere to it during testing, necessitating frequent disassembly and cleaning if they fall onto the platform, otherwise, conductive adhesive on the sample platform will affect subsequent tests.

Description

Technical Field

[0001] This utility model relates to the field of foam conductivity testing technology, and in particular to a non-destructive testing device for localized conductivity of foam. Background Technology

[0002] Foam, as a lightweight, porous, and highly elastic material, is widely used in electronics, automotive, and aerospace industries, especially in electronic devices where it is often used as a cushioning, sealing, or electromagnetic shielding material. Locally conductive foam plays a crucial role in electromagnetic compatibility (EMC) and electrostatic discharge (ESD) protection due to its unique conductivity. However, the conductivity of foam can degrade or fail locally due to material inhomogeneity, manufacturing defects, or aging during long-term use, affecting its functionality and reliability. Traditional conductivity testing methods typically employ contact measurements, such as the four-probe method or direct measurement with a multimeter. These methods require applying pressure or puncturing the foam, which may lead to material deformation or damage, and are particularly unsuitable for localized testing of soft or ultra-thin foams. Furthermore, existing non-contact testing technologies (such as eddy current testing or microwave testing) often lack sufficient sensitivity to the low conductivity or complex porous structure of foam, making it difficult to achieve high-resolution local defect localization. Therefore, there is an urgent need to develop a non-destructive testing device that can accurately and rapidly detect the local conductivity of foam without damaging it, to meet the needs of industrial production quality control and product maintenance.

[0003] During the use of the testing device, the foam on the sample platform needs to be tested for conductivity. The foam also needs to be adhered to materials such as conductive adhesive during the testing process. If it falls onto the sample platform, it needs to be disassembled and cleaned frequently. Otherwise, the conductive adhesive on the sample platform will affect the next test. Utility Model Content

[0004] This utility model relates to a non-destructive testing device for the local conductivity of foam. During the testing process, if conductive adhesive or other materials fall onto the sample platform, the platform is grasped and moved forward to remove it, and the debris on the sample platform is cleaned promptly. After each test of the foam's conductivity, the debris on the sample platform is cleaned to facilitate subsequent tests. Residual conductive materials may interfere with subsequent tests, leading to false positives (misjudged as conductive) or data deviations. The conductive adhesive, foam debris, and other debris remaining on the sample platform are conductive. If not cleaned in time, they may cause the testing probe to come into contact with the debris, forming additional conductive paths. This can cause the four-probe tester to misjudge the conductive area or conductivity value of the foam (such as an abnormally low resistance value), directly affecting the accurate assessment of the local conductivity of the foam.

[0005] In a first aspect, this utility model provides a non-destructive testing device for the local conductivity of foam, specifically comprising: a support plate; four threaded grooves respectively opened at both ends of the support plate; a support frame fixedly installed at the upper end of the support plate, and a through circular hole opened at the middle of the upper end of the support frame; a bearing plate fixedly installed on the inner side of the support frame; a support plate provided at the middle of the upper end of the bearing plate, and mutually symmetrical sliding grooves opened on the inner side of the support plate; a sample platform slidably installed at the middle of the upper end of the bearing plate, and sliding strips fixedly installed on both sides of the sample platform; and a handle fixedly installed at the front end of the sample platform.

[0006] Furthermore, a four-probe tester is installed in the middle of the upper part of the support plate, and a sensor is installed at the upper end of the four-probe tester, on which a four-probe lower electrode is fixedly installed.

[0007] Furthermore, the upper end of the support frame is provided with four guide holes, and the two ends of the lower end of the support frame are respectively fixedly installed with stabilizing plates, and four through bolts are inserted into the stabilizing plates.

[0008] Furthermore, a through-hole electric push rod is fixedly installed at the upper end of the support frame, and a connecting plate is fixedly installed at the lower end of the electric push rod.

[0009] Furthermore, vertically upward guide rods are fixedly installed at the four corners of the connecting plate, and four probe upper electrodes are installed in the middle of the bottom of the connecting plate.

[0010] Furthermore, symmetrical limiting plates are fixedly installed on the upper end of the bearing plate, and positioning strips are fixedly installed on the rear end of the bearing plate.

[0011] This invention provides a non-destructive testing device for the local conductivity of foam, which has the following advantages: In the use of this invention, during the testing of the local conductivity of foam, if conductive adhesive or other materials fall onto the sample platform, the sample platform is grasped and moved forward to remove it, and the debris on the sample platform is cleaned in time. After each test of the foam's conductivity, the debris on the sample platform is cleaned to facilitate the next test. Residual conductive materials may interfere with subsequent tests, leading to false positives (misjudged as conductive) or data deviations. The conductive adhesive, foam debris, and other debris remaining on the sample platform are conductive. If not cleaned in time, the test probe may come into contact with the debris, forming an additional conductive path. This may cause the four-probe tester to misjudge the conductive area or conductivity value of the foam (such as an abnormally low resistance value), directly affecting the accurate assessment of the local conductivity of the foam.

[0012] By using an electric push rod to push the connecting plate downwards, the downward movement stops when the bottom of both ends of the connecting plate touches the limiting plate. At this point, the four probe electrodes at the bottom of the connecting plate will perform conductivity testing on the foam on the sample platform. The driving force of the electric push rod is uniform and controllable, and the limiting plate precisely limits the downward movement endpoint, ensuring that the contact pressure and contact depth between the four probe electrodes and the foam are completely consistent in each test. This avoids problems such as probes being pressed too deeply / too shallowly or poor contact caused by uneven force during manual operation, thus ensuring standardized testing conditions from the source and making the data from different samples or multiple tests of the same sample comparable. Attached Figure Description

[0013] To more clearly illustrate the technical solution of this utility model, the accompanying drawings of the embodiments will be briefly described below.

[0014] In the attached diagram: Figure 1 A schematic diagram of the left front upper axis view structure of this application is shown; Figure 2 A schematic diagram of the front view structure of this application is shown; Figure 3 A schematic diagram of the disassembled structure of the support frame and bearing plate of this application is shown; Figure 4 A schematic diagram of the exploded structure of this application is shown.

[0015] List of reference numerals 1. Support plate; 101. Four-probe tester; 102. Sensor; 103. Lower electrode of four-probe; 2. Support frame; 201. Guide hole; 202. Stabilizing plate; 203. Electric push rod; 204. Connecting plate; 205. Guide rod; 206. Upper electrode of four-probe; 3. Bearing plate; 301. Limiting plate; 302. Positioning strip; 303. Support plate; 304. Slide groove; 305. Sample platform; 306. Slide bar. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the described embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0017] Example 1: Please refer to Figures 1 to 4 : This invention proposes a non-destructive testing device for the local conductivity of foam, comprising: a support plate 1; four threaded grooves are respectively formed at both ends of the support plate 1; a four-probe tester 101 is installed in the middle of the upper end of the support plate 1, a display screen is installed on the front side of the four-probe tester 101, the display screen intuitively displays the test data of the foam, and a sensor 102 is installed at the upper end of the four-probe tester 101, a four-probe lower electrode 103 is fixedly installed on the sensor 102, and the four probes of the four-probe upper electrode 206 can be accurately aligned with the local test point of the foam (such as a diameter of 1-2mm). The small area is controlled by a flat support surface of the lower electrode 103 of the four probes, which ensures uniform contact between the upper electrode 206 of the four probes and the local surface, thereby reducing the deviation of local resistance measurement caused by poor contact. A support frame 2 is fixedly installed on the upper end of the support plate 1, and a through circular hole is opened in the middle of the upper end of the support frame 2. A carrier plate 3 is fixedly installed on the inner side of the support frame 2. Symmetrical limiting plates 301 are fixedly installed on the upper end of the carrier plate 3. A positioning strip 302 is fixedly installed on the rear end of the carrier plate 3. A support plate 303 is provided in the middle of the upper end of the carrier plate 3. The sample platform 305 is slidably installed on the support plate 303. Symmetrical sliding grooves 304 are opened in the inner side of the support plate 303. The sample platform 305 is slidably installed in the middle of the upper end of the carrier plate 3. After the local conductivity test of the foam is completed, the sample platform 305 is grasped and moved towards the center. The sample platform 305 can be easily removed for cleaning. Slide bars 306 are fixedly installed on both sides of the sample platform 305. By grasping the handle on the sample platform 305 and pulling it forward, the sample platform 305 is moved to the front end of the support plate 303. Then, the foam is placed on the sample platform 305. Next, the sample platform 305 is pushed backward. It stops moving when the rear side of the sample platform 305 is in contact with the positioning strip 302. At this point, the conductivity of the foam is tested. The front end of the sample platform 305 has a handle for easy movement. The slide bars 306 are slidably installed in the slide groove 304. When the sample platform 305 slides back and forth, the slide bars 306 are restricted by the slide groove 304, allowing the sample platform 305 to slide only back and forth, preventing deviation or tilting during sliding.

[0018] The support frame 2 has four guide holes 201 at its upper end. Stabilizing plates 202 are fixedly installed at both ends of the lower end of the support frame 2. Four through bolts are inserted into the stabilizing plates 202. Rotating these bolts into the threaded grooves of the support plate 1 secures the stabilizing plates 202 and the support frame 2, preventing movement when the support frame 2 is touched. A through electric push rod 203 is fixedly installed at the round hole at the upper end of the support frame 2. Using the electric push rod 203 to push the connecting plate 204 downwards, the downward movement stops when the bottom ends of the connecting plate 204 are against the limiting plate 301, preventing damage to the foam caused by the four probe electrodes 206 at the bottom of the connecting plate 204. The four-probe upper electrode 206 at the bottom of the connecting plate 204 will perform conductivity testing on the foam on the sample platform 305. The lower end of the electric push rod 203 is fixedly installed with a connecting plate 204. Vertically upward guide rods 205 are fixedly installed at the four corners of the connecting plate 204. The guide rods 205 slide through the guide holes 201. When the connecting plate 204 slides up and down, the guide rods 205 are restricted by the guide holes 201, and the connecting plate 204 can only slide up and down to prevent the connecting plate 204 from shifting or tilting when sliding up and down. The four-probe upper electrode 206 at the bottom of the connecting plate 204 will also tilt and cannot stably test the conductivity of the foam. The four-probe upper electrode 206 is installed in the middle of the bottom of the connecting plate 204.

[0019] Example 2, based on Example 1, such as Figure 1 and Figure 4 As shown, two stabilizing plates 202 are fixedly installed at the two ends of the lower end of the support frame 2, and four through bolts are inserted on the stabilizing plates 202. After removing the stabilizing plates 202 and the bolts, the lower end of the support frame 2 is fixedly welded or glued to the support plate 1 to stabilize and restrict the support frame 2. In this way, the support frame 2 will not move when touched, avoiding the bolts from loosening and failing to stabilize the support frame 2 after long-term use, and also saving on component costs.

[0020] The working principle of this embodiment is as follows: When in use, grasp the handle on the sample platform 305 and pull it forward to move the sample platform 305 to the front end of the support plate 303. Then place the foam on the sample platform 305 and push the sample platform 305 backward. When the rear side of the sample platform 305 is in contact with the positioning strip 302, it will stop moving. At this time, the conductivity of the foam is tested. Use the electric push rod 203 to push the connecting plate 204 downward. When the bottom of both ends of the connecting plate 204 is in contact with the limiting plate 301, it will stop moving downward. At this time, the four-probe upper electrode 206 at the bottom of the connecting plate 204 will test the conductivity of the foam on the sample platform 305. The display screen on the four-probe tester 101 will display the test data of the foam intuitively. After the local conductivity of the foam is tested, grasp the sample platform 305 and move it forward to remove it for easy cleaning of debris on the sample platform 305 at any time.

[0021] The following points should be noted in this article: 1. The accompanying drawings of this utility model embodiment only involve the structures involved in this utility model embodiment; other structures can refer to general designs.

[0022] 2. Where there is no conflict, the embodiments of this utility model and the features in the embodiments can be combined with each other to obtain new embodiments.

[0023] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A non-destructive testing device for the local conductivity of foam, comprising: Support plate (1); four threaded grooves are respectively opened at both ends of the support plate (1); a support frame (2) is fixedly installed at the upper end of the support plate (1), and a through round hole is opened at the middle of the upper end of the support frame (2); characterized in that a bearing plate (3) is fixedly installed on the inner side of the support frame (2); a sample platform (305) is slidably installed at the middle of the upper end of the bearing plate (3), and slide bars (306) are fixedly installed on both sides of the sample platform (305); a handle is fixedly installed at the front end of the sample platform (305).

2. The non-destructive testing device for the local conductivity of foam according to claim 1, characterized in that: A four-probe tester (101) is installed in the middle of the upper end of the support plate (1), and a sensor (102) is installed on the upper end of the four-probe tester (101). A four-probe lower electrode (103) is fixedly installed on the sensor (102).

3. The non-destructive testing device for the local conductivity of foam according to claim 1, characterized in that: The upper end of the support frame (2) is provided with four guide holes (201), and the two ends of the lower end of the support frame (2) are respectively fixedly installed with stabilizing plates (202), and four through bolts are inserted on the stabilizing plates (202).

4. The non-destructive testing device for the local conductivity of foam according to claim 1, characterized in that: An electric push rod (203) is fixedly installed through the round hole at the upper end of the support frame (2), and a connecting plate (204) is fixedly installed at the lower end of the electric push rod (203).

5. The non-destructive testing device for the local conductivity of foam according to claim 4, characterized in that: The four corners of the connecting plate (204) are respectively fixed with vertically upward guide rods (205), and the bottom center of the connecting plate (204) is equipped with four probe upper electrodes (206).

6. The non-destructive testing device for the local conductivity of foam according to claim 1, characterized in that: The upper end of the bearing plate (3) is fixedly installed with mutually symmetrical limiting plates (301), and the rear end of the bearing plate (3) is fixedly installed with positioning strips (302).

7. The non-destructive testing device for the local conductivity of foam according to claim 1, characterized in that: The upper part of the bearing plate (3) is provided with a support plate (303), and the inner side of the support plate (303) is provided with mutually symmetrical grooves (304).

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