Test method for calibrating the scratch resistance of automotive glass

Abstract

This invention discloses a test method for calibrating the scratch resistance performance of automotive glass, relating to the field of automotive glass technology. The invention aims to create a scratch of a preset length on the target edge of the automotive glass under test. A hardness tester is used to scratch the glass, gradually increasing the load with each scratch. If the glass breaks during a scratch, the load from the previous scratch is taken as the critical load, i.e., the pass standard for the scratch resistance performance of the automotive glass, thus achieving accurate calibration of the pass standard for the scratch resistance performance of automotive glass.

Description

Technical Field

[0001] This invention relates to the field of automotive glass technology, and in particular to a test method for calibrating the scratch resistance of automotive glass. Background Technology

[0002] GB9656 "Safety Glass for Automobiles" specifies the main performance requirements and test methods for automotive glass, including abrasion resistance, heat resistance, penetration resistance, and impact resistance. However, it does not specify the scratch resistance of automotive glass. In actual use, the risk of scratches on automotive glass is second only to the risk of impact. Scratches not only affect the appearance of the glass, but when the scratch occurs at the edge of the glass, it can easily cause the glass to break, leading to safety hazards. Therefore, it is of great significance to stipulate the qualification standard for scratch resistance of automotive glass, which can screen out products that do not meet the scratch resistance performance and reduce safety hazards. However, at present, the industry has not provided a test method that can accurately calibrate the qualification standard for scratch resistance of automotive glass. Summary of the Invention

[0003] This invention solves the technical problem of how to calibrate the pass standard for scratch resistance performance of automotive glass by providing a test method for calibrating the scratch resistance performance of automotive glass.

[0004] This invention provides the following technical solution:

[0005] A test method for calibrating the scratch resistance of automotive glass includes:

[0006] The purpose is to create a scratch of a preset length on the target edge of the car glass to be tested, and the car glass to be tested is scratched using a hardness tester.

[0007] If the car glass under test does not break during the current scratching process, the next scratching will be performed in the un-scratched area at a preset distance from the target scratch. The target scratch is the scratch formed after the current scratching of the car glass under test. The load applied to the car glass under test by the next scratching is greater than the load applied to the car glass under test by the current scratching.

[0008] If the car glass under test breaks during the current scratching process, the load applied to the car glass under test during the previous scratching will be taken as the critical load of the car glass under test.

[0009] Preferably, the target edge is an easily scratched edge, a normally scratched edge, or a difficult-to-scratch edge, and the preset distance corresponding to the easily scratched edge, the normally scratched edge, and the difficult-to-scratch edge increases sequentially.

[0010] Preferably, the preset distances corresponding to the easily scratched edge, the edge with a normal probability of scratching, and the edge that is difficult to scratch are 60mm, 100mm, and 150mm, respectively.

[0011] Preferably, the preset lengths corresponding to the easily scratched edge, the normally scratched edge, and the difficult-to-scratch edge decrease sequentially.

[0012] Preferably, the preset lengths corresponding to the easily scratched edge, the edge with a normal probability of scratching, and the edge that is difficult to scratch are 50mm, 30mm, and 20mm, respectively.

[0013] Preferably, the automotive glass to be tested is any one of framed door windows, frameless door windows, front and rear windshields, and front and rear triangular glass;

[0014] When the car glass to be tested is a framed car door window, the easily scratched edge is the upper edge of the framed car door window, and the generally probable scratched edge is the left edge, right edge, or lower edge of the framed car door window.

[0015] When the car glass to be tested is a frameless car door window, the easily scratched edge is the upper edge, left edge or right edge of the frameless car door window, and the generally probable scratched edge is the lower edge of the frameless car door window.

[0016] When the car glass to be tested is the front and rear windshields, the edge of the scratch with a general probability is the upper or lower edge of the front and rear windshields, and the edge of the scratch with a difficult probability is the left or right edge of the front and rear windshields.

[0017] When the car glass to be tested is a front and rear triangular glass, the scratch-resistant edge is any edge of the front and rear triangular glass.

[0018] Preferably, before scratching the automotive glass with a hardness tester, with the aim of creating a scratch of a preset length on the target edge of the glass to be tested, the method further includes:

[0019] The bracket with suction cups is fixed to the base, a sample piece identical to the car glass to be tested is adsorbed onto the suction cup, and the car glass to be tested is placed on the sample piece.

[0020] Preferably, placing the automotive glass to be tested on the sample includes:

[0021] Bubble paper is placed on the surface of the sample, and then the car glass to be tested is placed on the bubble paper so that the car glass to be tested is stacked on the sample.

[0022] Preferably, before scratching the automotive glass with a hardness tester, with the aim of creating a scratch of a preset length on the target edge of the glass to be tested, the method further includes:

[0023] The annealed tempered glass is placed on the pressure sensor, and the pressure sensor is connected to the force gauge;

[0024] The hardness tester applies a preset load to the tempered glass using a load cell;

[0025] If the difference in readings between the force gauge and the load cell is higher than a preset difference, the hardness tester is calibrated until the difference in readings between the force gauge and the load cell is lower than the preset difference.

[0026] Preferably, before scratching the automotive glass with a hardness tester, with the aim of creating a scratch of a preset length on the target edge of the glass to be tested, the method further includes:

[0027] The car glass to be tested is placed in an environment with a temperature of 21-25℃ and a humidity of 45%-55% for a preset time.

[0028] The technical solution provided by this invention has at least the following technical effects or advantages:

[0029] This invention aims to create a scratch of a preset length on the target edge of the automotive glass to be tested. The automotive glass to be tested is scratched using a hardness tester, and the load of each scratch is gradually increased. If the automotive glass to be tested breaks during a certain scratch, the scratch load of the previous scratch is taken as the critical load of the automotive glass to be tested, that is, the pass standard for the scratch resistance performance of the automotive glass to be tested. This invention achieves accurate calibration of the pass standard for the scratch resistance performance of automotive glass. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a flowchart of the test method for calibrating the scratch resistance of automotive glass in an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the test method for calibrating the scratch resistance of automotive glass in an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of the framed car door and window structure in an embodiment of the present invention;

[0034] Figure 4 This is a schematic diagram of the frameless car door and window structure in an embodiment of the present invention;

[0035] Figure 5 This is a schematic diagram of the front and rear windshields in an embodiment of the present invention;

[0036] Figure 6 This is a schematic diagram of the front and rear triangular glass structures in an embodiment of the present invention;

[0037] Figure 7 This is a schematic diagram of the structure of the test bench in an embodiment of the present invention;

[0038] Figure 8 This is a schematic diagram of the calibration of the hardness tester in an embodiment of the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 10-Base; 11-Support; 12-Sample piece; 13-Load gauge; 14-Hardness tester; 15-Tempered glass; 16-Pressure sensor; 17-Force gauge. Detailed Implementation

[0041] This invention provides a test method for calibrating the scratch resistance performance of automotive glass, thus solving the technical problem of how to calibrate the pass standard for scratch resistance performance of automotive glass.

[0042] To better understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] like Figure 1 As shown, the test method for calibrating the scratch resistance of automotive glass in this embodiment includes:

[0044] Step S1: To form a scratch of a preset length on the target edge of the car glass to be tested, a hardness tester is used to scratch the car glass to be tested.

[0045] Step S2: If the car glass under test does not break during this scratching process, the next scratching is performed in the unscratched area at a preset distance from the target scratch. The target scratch is the scratch formed after this scratching of the car glass under test. The load applied to the car glass under test in the next scratching is greater than the load applied to the car glass under test in the current scratching.

[0046] Step S3: If the car glass to be tested breaks during this scratching process, the load applied to the car glass to be tested during the previous scratching is taken as the critical load of the car glass to be tested.

[0047] In this embodiment, the automobile glass to be tested can be any standard piece of glass on an automobile, such as any one of framed door windows, frameless door windows, front and rear windshields, and front and rear triangular glass. The scratch resistance of automobile glass at various positions can be calibrated one by one. The target edge can be any edge of the automobile glass to be tested. The preset length can be an average value or the most common value of all scratch lengths of automobile glass during the life cycle obtained through big data statistics.

[0048] Based on Figure 2 The experimental method of this embodiment will be described. First, a first scribing is performed on the automobile glass to be tested by a hardness tester, wherein the hardness tester can be controlled to apply a small load to the automobile glass to be tested. The automobile glass to be tested does not break during the first scribing, a first scratch is formed on the automobile glass to be tested after the first scribing, the length of the first scratch is the preset length, and the first scratch starts from the target edge and extends to the middle of the automobile glass to be tested; then a second scribing is performed at a position at a preset distance from the first scratch by the hardness tester, the load applied to the automobile glass to be tested in the second scribing is greater than the load applied to the automobile glass to be tested in the first scribing, the automobile glass to be tested also does not break during the second scribing, a second scratch is formed on the automobile glass to be tested after the second scribing, the length of the second scratch is the preset length, the second scratch starts from the target edge and extends to the middle of the automobile glass to be tested, and the second scratch can be parallel or non-parallel to the first scratch; ......; and so on, the scribing load is gradually increased until the automobile glass to be tested breaks, and the load of the last scribing before the breaking of the automobile glass to be tested is taken as the critical load of the automobile glass to be tested, that is, the qualification standard of the scratch resistance of the automobile glass to be tested. For the same type of automobile glass produced subsequently, only when the scratch resistance of the target edge or each edge is greater than the critical load can it be judged as qualified. It can be understood that after the automobile glass is assembled on an automobile, it will be scratched many times, and the force of each scratch will also be different. In the method of this embodiment, when calibrating the critical load, the automobile glass to be tested is scribed multiple times, and the scribing load is gradually increased, which simulates the real scratching scenario of the glass on the automobile to a certain extent, and the obtained critical load of the automobile glass to be tested is more reliable.

[0049] Considering that the result after a scribing experiment on one piece of automobile glass to be tested may be accidental, in this embodiment, if the automobile glass to be tested a breaks during the N-th scribing, three other pieces of automobile glass to be tested b, c and d are additionally selected for scribing respectively. If b also breaks during the N-th scribing, and c and d do not break after the (N-1)-th scribing, it proves that the breaking of a during the N-th scribing is not accidental, and the load applied during the (N-1)-th scribing to a can be taken as its critical load.

[0050] Understandably, in a real-world environment, the probability of scratching each edge of a car window varies depending on its location. Some edges are easily scratched, while others are not. Easily scratched edges have more, longer, and denser scratches, while less easily scratched edges have fewer, shorter, and sparser scratches. Therefore, applying the same preset distance and length to different target edges would result in a low similarity between the experimental method and the real-world scenario, leading to low reliability of the critical load on the tested car window. To improve the simulation of real-world scenarios, in this embodiment, the target edges are categorized as easily scratched edges, moderately probable scratched edges, or difficult-to-scratch edges. The preset distances for easily scratched edges, moderately probable scratched edges, and difficult-to-scratch edges increase sequentially, while the preset lengths decrease sequentially. Easily scratched edges can be considered edges that can move and are not protected by other parts at certain stages of their movement; moderately probable scratched edges can be considered edges fixed by adhesive and exposed to accessible external surfaces, or moving edges that are always protected by other parts during movement; difficult-to-scratch edges can be considered fixed edges that are protected by other parts. The preset distances for easily scratched edges, moderately probable scratched edges, and difficult-to-scratch edges can be 60mm, 100mm, and 150mm, respectively, and the corresponding preset lengths can be 50mm, 30mm, and 20mm, respectively. This ensures that when conducting scratch tests on these edges, the easily scratched edges have the smallest spacing and the longest scratch length, followed by the moderately probable scratched edges, and the difficult-to-scratch edges have the largest spacing and the shortest scratch length. Therefore, scratching the easily scratched edges results in the lowest scratch load when the tested car glass breaks, followed by the moderately probable scratched edges, and the most severe scratching occurs when the difficult-to-scratch edges break, thus reflecting the real-world scratching scenarios for automotive glass. This embodiment can perform a scratch test on each edge of the same piece of automotive glass to be tested. The critical load of the target edge is used as the qualification standard for the scratch resistance performance of the target edge. Different edges have different qualification standards for scratch resistance performance. The qualification standard for scratch-prone edges is the lowest, the qualification standard for scratch-probability edges is the second lowest, and the qualification standard for scratch-difficult edges is the highest.Of course, a scratch test can also be performed on only one edge of the automotive glass under test, and the resulting critical load can be used as the pass standard for the scratch resistance performance of the entire automotive glass under test. However, when the easily scratched edge is selected as the target edge, the pass standard for the scratch resistance performance of the entire automotive glass under test is the lowest, and the requirements for the scratch resistance performance of the product are low, which is conducive to improving the product pass rate. When the edge with a moderate probability of scratching is selected as the target edge, the pass standard for the scratch resistance performance of the entire automotive glass under test is moderate, and the requirements for the scratch resistance performance of the product are moderate, which can balance the product pass rate and scratch resistance performance. When the difficult-to-scratch edge is selected as the target edge, the pass standard for the scratch resistance performance of the entire automotive glass under test is high, and the requirements for the scratch resistance performance of the product are high, which will reduce the product pass rate.

[0051] In this embodiment, when the car glass to be tested is a framed door window, the framed door window only has easily scratched edges and edges with a moderate probability of scratching. The easily scratched edge is the upper edge of the framed door window, and the edges with a moderate probability of scratching are the left, right, or lower edge of the framed door window. Figure 3 As shown; when the car glass under test is a frameless door window, the frameless door window only has easily scratched edges and edges with a moderate probability of scratching. The easily scratched edges are the top, left, or right edges of the frameless door window, and the edges with a moderate probability of scratching are the bottom edges of the frameless door window, such as... Figure 4 As shown; when the car glass under test is the front and rear windshields, the front and rear windshields only have scratch edges with a general probability of scratching and scratch-resistant edges. Scratch edges with a general probability of scratching are the upper or lower edges of the front and rear windshields, and scratch-resistant edges are the left or right edges of the front and rear windshields. Figure 5 As shown; when the car glass to be tested is a front and rear triangular glass, the front and rear triangular glass only has scratch-resistant edges, and the scratch-resistant edges are all edges of the front and rear triangular glass, such as... Figure 6 As shown.

[0052] In this embodiment, before scratching the automotive glass to be tested, it is necessary to install and fix the automotive glass to be tested. Therefore, before step S1, the test method for calibrating the scratch resistance performance of automotive glass may further include: fixing a bracket with a suction cup to a base, adsorbing a sample piece identical to the automotive glass to be tested onto the suction cup, and placing the automotive glass to be tested on the sample piece. The test platform consisting of the base, the bracket with a suction cup, and the sample piece is as follows: Figure 7 As shown, the suction cup can effectively reduce the load applied to the glass. To provide better protection for the automotive glass under test and improve the reliability of the experimental results, placing the automotive glass under test on the sample can include: placing bubble paper on the surface of the sample, and then placing the automotive glass under test on the bubble paper, so that the automotive glass under test is stacked on the sample. The bubble paper can provide better protection for the automotive glass under test.

[0053] Understandably, if the hardness tester's error is too large, the obtained critical load will be incorrect. Therefore, the accuracy of the hardness tester needs to be checked before the experiment, and calibration should be performed if the error is too large. Before step S1, the test method for calibrating the scratch resistance of automotive glass can also include: placing the annealed tempered glass on a pressure sensor and connecting the pressure sensor to a force gauge; applying a preset load to the tempered glass using a load cell; if the reading difference between the force cell and the load cell is higher than a preset difference, calibrating the hardness tester until the reading difference is lower than the preset difference. A schematic diagram of the hardness tester calibration is shown below. Figure 8 As shown, the annealed tempered glass has the same properties as the automotive glass being tested. This ensures that the contact scenario between the hardness tester and the annealed tempered glass is the same, which is beneficial for accurately determining whether the hardness tester's error is too large.

[0054] To further improve the reliability of the critical load, before step S1, the test method for calibrating the scratch resistance of automotive glass may further include: placing the automotive glass to be tested in an environment with a temperature of 21-25℃ and a humidity of 45%-55% for a preset time. The environment of 21-25℃ and 45%-55% humidity simulates the real-world usage environment of automotive glass, thereby improving the reliability of the critical load.

[0055] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0056] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A test method for calibrating the scratch resistance of automotive glass, characterized in that, include: The purpose is to create a scratch of a preset length on the target edge of the car glass to be tested, and the car glass to be tested is scratched using a hardness tester. If the car glass under test does not break during the current scratching process, the next scratching will be performed in the un-scratched area at a preset distance from the target scratch. The target scratch is the scratch formed after the current scratching of the car glass under test. The load applied to the car glass under test by the next scratching is greater than the load applied to the car glass under test by the current scratching. If the car glass under test breaks during the current scratching process, the load applied to the car glass under test during the previous scratching will be taken as the critical load of the car glass under test. The target edge is a scratch-prone edge, a scratch-probability edge, or a scratch-difficult edge. The preset distances corresponding to the scratch-prone edge, the scratch-probability edge, and the scratch-difficult edge increase sequentially, while the preset lengths corresponding to them decrease.

2. The test method for calibrating the scratch resistance of automotive glass as described in claim 1, characterized in that, The preset distances corresponding to the easily scratched edge, the edge with a normal probability of scratching, and the edge that is difficult to scratch are 60mm, 100mm, and 150mm, respectively.

3. The test method for calibrating the scratch resistance of automotive glass as described in claim 1, characterized in that, The preset lengths corresponding to the easily scratched edge, the edge with a normal probability of scratching, and the edge that is difficult to scratch are 50mm, 30mm, and 20mm, respectively.

4. The test method for calibrating the scratch resistance of automotive glass as described in claim 1, characterized in that, The automotive glass to be tested is any one of framed door windows, frameless door windows, front and rear windshields, and front and rear triangular glass. When the car glass to be tested is a framed car door window, the easily scratched edge is the upper edge of the framed car door window, and the generally probable scratched edge is the left edge, right edge, or lower edge of the framed car door window. When the car glass to be tested is a frameless car door window, the easily scratched edge is the upper edge, left edge or right edge of the frameless car door window, and the generally probable scratched edge is the lower edge of the frameless car door window. When the car glass to be tested is the front and rear windshields, the edge of the scratch with a general probability is the upper or lower edge of the front and rear windshields, and the edge of the scratch with a difficult probability is the left or right edge of the front and rear windshields. When the car glass to be tested is a front and rear triangular glass, the scratch-resistant edge is any edge of the front and rear triangular glass.

5. The test method for calibrating the scratch resistance of automotive glass as described in claim 1, characterized in that, Before scratching the automotive glass with a hardness tester, with the aim of creating a scratch of a preset length on the target edge of the glass to be tested, the process also includes: The bracket with suction cups is fixed to the base, a sample piece identical to the car glass to be tested is adsorbed onto the suction cup, and the car glass to be tested is placed on the sample piece.

6. The test method for calibrating the scratch resistance of automotive glass as described in claim 5, characterized in that, Placing the car glass to be tested on the sample piece includes: Bubble paper is placed on the surface of the sample, and then the car glass to be tested is placed on the bubble paper so that the car glass to be tested is stacked on the sample.

7. The test method for calibrating the scratch resistance of automotive glass as described in claim 1, characterized in that, Before scratching the automotive glass with a hardness tester, with the aim of creating a scratch of a preset length on the target edge of the glass to be tested, the process also includes: The car glass to be tested is placed in an environment with a temperature of 21-25℃ and a humidity of 45%-55% for a preset time.

8. The test method for calibrating the scratch resistance of automotive glass as described in claim 1, characterized in that, The easily scratched edge is an edge that can move and is not protected by other parts at certain stages of the movement; the edge with a general probability of scratching is an edge that is fixed by adhesive and exposed to an accessible outer surface, or an edge that can move and is always protected by other parts during the movement; the edge that is difficult to scratch is an edge that is fixed and protected by other parts.

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