JP2021179326A - Method for calibrating wear testing device and wear testing device - Google Patents

Abstract

To provide a method for calibrating a wear testing device and the wear testing device, with which it is possible to apply an exact load.SOLUTION: There is provided a method for calibrating a wear testing device, with which, while applying a prescribed load F at a prescribed angle to a test surface of a test piece TP1-TP3, a test piston PS1-PS3 is reciprocated a prescribed number of times, and then the wear characteristic value of the test surface is evaluated. The loads FD, FS+FD that acts upon the test surface while the test piston is sliding on the test surface are detected, and the wear testing device is calibrated so that the loads acting upon the test surface fall within a permissible range that includes the prescribed load.SELECTED DRAWING: Figure 7

Description

The present invention relates to a calibration method for a wear test device and a wear test device.

Part 2-70 of Japanese Industrial Standards JIS (formerly known as Japanese Industrial Standards) is entitled "Abrasion test of printing by rubbing fingers and hands", and the force of rubbing with fingers and hands may be applied during use. It specifies a test method for printing on certain electrical components, such as switches, plugs, and handles. In this test method, the test piston is repeatedly slid a predetermined number of times while applying a predetermined load at an angle of 45 ° ± 5 ° to the surface to be tested, and then the wet contact angle (WCA) of the surface to be tested is determined. Evaluate the characteristic value.

JIS C6000068-2-70

In the above-mentioned abrasion test JIS C600726-2-70, the pressing load applied to the test piston is specified, but if the calibration of the test device is not appropriate, when the repeated load is applied, the above JIS will be used. There is a problem that the specified predetermined load cannot be applied accurately.

An object to be solved by the present invention is to provide a calibration method and a wear test device of a wear test device capable of applying an accurate load.

The present invention is a method for calibrating a wear test device that evaluates the characteristic value of the surface to be tested after sliding the test piston back and forth a predetermined number of times while applying a predetermined load to the surface to be tested at a predetermined angle.
The load acting on the test surface while the test piston is sliding with respect to the test surface is detected.
The above problem is solved by calibrating the wear test apparatus so that the load acting on the surface to be tested belongs to the allowable range including the predetermined load.

Further, the present invention is provided with a test piston that applies a predetermined load to the test surface of the test piece at a predetermined angle, and after sliding the test piston back and forth a predetermined number of times, the wear characteristic value of the test surface is evaluated. In the wear test equipment
A load sensor that detects the load acting on the surface under test while the test piston is sliding with respect to the surface under test.
The above problem is solved by a wear test apparatus having a calibration means for calibrating the load of the test piston on the surface to be measured so that the load detected by the load sensor belongs to the allowable range including the predetermined load.

According to the present invention, since the load while the test piston is sliding on the surface under test is detected and used as the calibration reference value of the wear test apparatus, it is possible to perform a test in which an accurate load is applied. ..

It is a schematic diagram which shows an example of the test apparatus which concerns on the calibration method of the wear test apparatus of this invention. It is a side view which shows the main part of the wear test apparatus which concerns on this invention. It is a top view which shows the main part of the wear test apparatus which concerns on this invention. It is a figure which shows the load acting from the test piston to the test surface SF of a test piece. It is a side view (the 1) of the main part which shows the operation of the wear test apparatus of FIG. FIG. 2 is a side view (No. 2) of a main part showing the operation of the wear test apparatus of FIG. It is a graph which shows the measurement result of the applied load of the wear test apparatus of FIG. It is a side view for demonstrating the calibration method of the wear test apparatus of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, with reference to FIG. 1, an example of a test method related to the calibration method of the wear test apparatus of the present invention will be described. FIG. 1 is a schematic view showing an example of a test apparatus preferable for use in a wear test of printing due to rubbing of a finger and a hand specified by Japanese Industrial Standard JIS C6000068-2-70. This standard specifies test methods for prints formed on electrical components that may be rubbed by fingers and hands during use, such as keyboards, switches, plugs, handles, etc., and keyboards that are handled by hand. It defines a standard method for defining the wear resistance of flat or curved prints such as. This test method is also suitable for testing the durability against liquids generated under normal use environment.

The wear test apparatus 1 shown in FIG. 1 is supported by a base 11 for fixing the test piece TP having the test piece TP and the test piece TP at an angle of 45 ° ± 5 ° with respect to the test piece TP, and is air. It includes a test piston PS that reciprocates via a rod 12 of a cylinder and the like, and a cloth piece 13 that is installed between the test piston PS and the surface SF to be tested.

The test piston PS is made of, for example, an elastic material that does not react with the test solution, and is made of a material having a shore A hardness of 47 ± 5, such as synthetic rubber. Due to the elasticity of the tip, it can be deformed to fit the surface SF to be tested. The size of the test piston PS is selected from two predetermined types according to the shape and size of the specimen and the type of printing. For example, the diameter is 20 mm and the tip surface is R = 20 mm. The material, hardness, shape and operating angle of the test piston PS are selected so that they are pressurized and rubbed in the same way as a human finger.

The test piston PS slides while being in contact with the test surface SF of the test piece TP at an angle of 45 ° ± 5 ° due to the reciprocating motion of the rod 12 of the air cylinder. The sliding width L of the test piston PS is 1 mm to 4 mm, the sliding speed is 60 ± 30 mm / sec, the pressurizing time is 0.2 seconds or more, and the test cycle is 2 ± 0.5 times / sec. The sliding width L, sliding speed, and test cycle are defined by the specifications of the product to be tested. The surface compression time of the test piston PS and the elevating time of the test piston PS are set to be substantially equal to each other.

As a result, the surface SF under test is repeatedly stressed by the test piston. The force F in the direction perpendicular to the surface acting on the surface SF to be tested from the test piston PS and the number of times N of repeated slidings are determined by the standard of the product to be tested. For example, the force F is 1N ± 0.2N, 5N ± 1N, 10N ± 2N, 50N ± 10N, 100N ± 20N. Further, for example, the number of repetitions N is 10, 100, 1000, 10,000, 100,000, 1 million, and 10 million.

For the sliding portion of the test piece TP that has completed the above wear test, the wear characteristic value is measured and the product to be tested is evaluated. For example, in the case of a wear test of a protective film formed on the surface of a glass substrate, the quality and reliability of the protective film are evaluated by measuring the wet contact angle (WCA) of the surface SF to be tested.

FIG. 2A is a side view showing a main part of the wear test apparatus 1 of the present embodiment, and FIG. 2B is a plan view. The wear test device 1 of the present embodiment is wound with a base 11, three sets of test pistons PS1 to PS3, three sets of holders H1 to H3 for holding three test pieces TP1 to TP3, and a cloth piece 13. It is provided with three sets of rollers R1 to R3 and three sets of nozzles (not shown) for applying a solution such as artificial sweat to the cloth piece 13. Each of the test pistons PS1 to PS3 is attached to the tip of the rod 12 of the air cylinder 14 having the rod 12 that moves back and forth. The air cylinder 14 is rotatably supported about the shaft C1 with respect to the base 11, and when the rod 12 is retracted and the test pistons PS1 to PS3 are separated from the test pieces TP1 to TP3, the air cylinder 14 is rearward of the air cylinder 14. Since the end abuts on the stopper 15, the angle θ between the axial direction and the horizontal direction of the rod 12 becomes 45 ± 5 °.

Since the air cylinder 14 moves forward and backward due to the driving air of a constant pressure, the applied load to the test pieces TP1 to TP3 becomes a constant value, but the air cylinder 14 is used to change the applied load to the test pieces TP1 to TP3. A weight W is provided on the test piston side of the shaft C1 so that the position of the air cylinder 14 in the axial direction can be adjusted. That is, when the weight W is moved to the tip side (test piston side) of the air cylinder 14, the moment generated at the tip of the test piston, that is, the load applied to the test piece increases, and conversely, the weight W is moved after the air cylinder 14. When moving to the end side (the side opposite to the test piston), the moment generated at the tip of the test piston, that is, the load applied to the test piece becomes smaller. In this way, by adjusting the position of the weight W with reference to the pressure of the driving air of the air cylinder 14, the force F of the wear test shown in FIG. 1 can be set.

FIG. 3 is a diagram showing the load acting on the test surface SF of the test pieces TP1 to TP3 from the test pistons PS1 to PS3. When the rod of the air cylinder 14 advances and the tip of the test piston PS comes into contact with the surface SF to be tested, the pressing load F1 due to the driving air pressure of the air cylinder 14 acts in the θ direction diagonally upward from the contact point. At the same time, the moment F2 due to the weight (including the weight W) of the air cylinder 14 having the axis C1 as the center of rotation acts in the θ direction diagonally downward from the contact point. As shown in the figure, the force F acting directly on the surface SF to be tested is the sum of the component force F1x in the direction perpendicular to the surface of F1 and the component force F2x in the direction perpendicular to the surface of F2.

4 and 5 (A) to 5 (D) are side views of the main parts showing the operation of the wear test device 1 of the present embodiment, and FIG. 4 (A) shows the rod 12 of the air cylinder 14 in the retracted position. It shows a state in which the tips of the test pistons PS1 to PS3 are separated from the test surface SF of the test pieces TP1 to TP3. FIG. 4B shows a state in which the rod 12 of the air cylinder 14 starts to move forward and the tips of the test pistons PS1 to PS3 come into contact with the surface SF of the test pieces TP1 to TP3. In FIG. 5C, the rod 12 of the air cylinder 14 further advances and the tips of the test pistons PS1 to PS3 rise while in contact with the test surface SF of the test pieces TP1 to TP3, and slide by the sliding width L. Indicates the state of operation. FIG. 5D shows a state in which the rod 12 of the air cylinder 14 begins to retract and the tips of the test pistons PS1 to PS3 descend while in contact with the test surface SF of the test pieces TP1 to TP3.

When the wear test device 1 of the present embodiment starts the wear test from the state shown in FIG. 4 (A), the rod of the air cylinder 14 reciprocates, so that FIG. 4 (B) → FIG. 5 (C) → FIG. The sliding motion with 5 (D) as one cycle is repeated. It is the sliding motion between FIGS. 4 (B) and 5 (C) that the tip of the test piston PS applies a predetermined load F to the surface SF of the test piece TP, and FIG. 5 (C). ) To FIG. 5 (D), the predetermined load F is not applied.

By the way, in the wear test apparatus 1 of the present embodiment configured as described above, the predetermined load F can be adjusted by the position of the weight W as described above, and before starting a desired wear test such as JIS C6000068-2-70. In addition, the calibration work (calibration work) of the applied load is performed. Specifically, by adjusting the position of the weight W, the moment F2 shown in FIG. 3 is adjusted, and calibration is performed so that F = F1x + F2x becomes a predetermined load. Here, the load applied to the test surface SF in the sliding motion in which FIG. 4 (B) → FIG. 5 (C) → FIG. 5 (D) is one cycle fluctuates as shown in FIG. FIG. 6 is a graph showing the measurement results of the applied load of the wear test apparatus 1 of the present embodiment, in which the horizontal axis represents time and the vertical axis represents the applied load.

That is, as shown in FIG. 4B, even if the tip of the test piston PS comes into contact with the test surface SF of the test piece TP and the rod 12 of the air cylinder 14 further advances from here, the tip of the test piston PS and the tip of the test piston PS. Since a static frictional force acts between the surface SF to be tested, the load acting on the surface SF to be tested temporarily increases (the time axis in FIG. 6 is "contact" to "start of sliding"). Subsequently, when the rod 12 of the air cylinder 14 further advances and the load acting on the test surface SF exceeds the static friction force, the tip of the test piston PS begins to slide with respect to the test surface SF (FIG. 6). The time axis is "starting sliding"). Then, when the tip of the test piston PS begins to slide with respect to the surface SF to be tested, the sliding ends while a dynamic friction force smaller than the static friction force acts (the time axis in FIG. 6 is "sliding start" to "sliding start". End of sliding "). For example, as the load applied to the surface SF to be tested in the wear test, the load FD while the dynamic friction force is acting can be used instead of the load FS while the static friction force is acting.

Therefore, in the calibration of the wear test apparatus 1 of the present embodiment, the load FD acting on the surface SF to be tested is measured while the test piston PS is sliding with respect to the surface SF to be tested, and this is tested. The position of the weight W of the wear test apparatus 1 is calibrated so that the load FD acting on the surface SF _{belongs to the allowable range FD 0 ± Δ1 including the predetermined load.}

Further, in the calibration of the wear test apparatus 1 of the present embodiment, the load FD _{belongs to the allowable range FD 0} ± Δ1 including a predetermined load, and the test piston PS “contacts” the surface SF to be tested. ~ The position of the weight W of the wear test device 1 so that the load FS from "start of sliding" is measured and the load FS acting on the surface SF to be tested _{belongs to the allowable range FS 0 ± Δ2 including the predetermined load.} May be calibrated.

Further, in the calibration of the wear test apparatus 1 of the present embodiment, the test piston PS measures the load FS from "contact" to "start of sliding" with respect to the test surface SF, and the test piston PS is tested. The load FD acting on the surface SF to be tested while sliding with respect to the surface SF is measured, and the load FS + FD acting on the surface SF to be tested includes an allowable range (FS ₀ + FD _{0) including a predetermined load.} ) The position of the weight W of the wear test apparatus 1 may be calibrated so as to belong to ± Δ3.

FIG. 7 is a side view for explaining a calibration method of the wear test apparatus 1 of the present embodiment. Specifically, first, the holders H1 to H3 shown in FIG. 2 are replaced with a measuring holder HM having a load sensor MS as shown in FIG. 7, and the output terminal of the load sensor MS is connected to the recording device PR. Then, the test piece TP is attached to the measurement holder HM, and the cloth piece 13 wound around the rollers R1 to R3 is cut out and fixed to the test pistons PS1 to PS3, or the cloth piece wound around the rollers R1 to R3. 13 is hung between the test pistons PS1 to PS3 and the test pieces TP1 to TP3, and the sliding motion in which FIG. 4 (B) → FIG. 5 (C) → FIG. 5 (D) is one cycle is repeated several times. At this time, the load measured by the load sensor MS is recorded in the recording device PR. Subsequently, from the recorded output graph, as shown in FIG. 6, the loads FD, FD and FS measured while the tip of the test piston PS is sliding with respect to the test surface SF of the test piece or After adjusting the position of the weight W so that the FS + FD belongs to the predetermined load range of the target test, the sliding with FIG. 4 (B) → FIG. 5 (C) → FIG. 5 (D) as one cycle again. Repeat the movement several times to check if the adjustment is done properly.

According to the wear test device 1 of the present embodiment calibrated in this way, the load while the test piston PS is sliding on the test surface SF is detected, and this is used as the calibration reference value of the wear test device 1. Therefore, it is possible to perform a test in which an accurate load is applied.

Various conditions of the wear test described in the present embodiment, for example, specific numerical values such as the sliding width L, the sliding speed, the pressurizing time, and the test cycle of the test piston PS are not particularly limited, and the test is performed. It can be changed arbitrarily depending on the standard of the target product.

1 ... Wear test device 11 ... Base 12 ... Rod 13 ... Cloth piece 14 ... Air cylinder 15 ... Stopper PS, PS1, PS2, PS3 ... Test piston C1 ... Shaft H1, H2, H3 ... Holder HM ... Measurement holder R1, R2, R3 ... Roll G1, G2, G3 ... Guide W ... Weight MS ... Load sensor PR ... Recording device TP, TP1, TP2, TP3 ... Test piece SF ... Tested surface

Claims (6)

In the calibration method of the wear test device that evaluates the wear characteristic value of the test surface after sliding the test piston back and forth a predetermined number of times while applying a predetermined load to the test surface of the test piece at a predetermined angle.
The load acting on the test surface while the test piston is sliding with respect to the test surface is detected.
A method for calibrating a wear test device that calibrates the wear test device so that the load acting on the surface to be tested belongs to an allowable range including the predetermined load. The calibration method for the wear test device according to claim 1, wherein the wear test device conforms to a wear test for printing due to rubbing of fingers and hands of Japanese Industrial Standards JIS C6000068 No. 2-70. The method for calibrating a wear test device according to claim 1 or 2, wherein the wear test device is provided with a plurality of the test pistons and simultaneously executes a wear test of a plurality of test pieces. In a wear test device that includes a test piston that applies a predetermined load to the surface to be tested at a predetermined angle, slides the test piston back and forth a predetermined number of times, and then evaluates the wear characteristic value of the surface to be tested.
A load sensor that detects the load acting on the surface under test while the test piston is sliding with respect to the surface under test.
A wear test apparatus having a calibration means for calibrating the load of the test piston on the surface to be measured so that the load detected by the load sensor belongs to the allowable range including the predetermined load. The fourth aspect of claim 4 comprises a recording device for recording the load output from the load sensor, wherein the calibration means calibrates the load of the test piston on the measured surface based on the load recorded on the recording device. Abrasion tester. The wear test apparatus according to claim 4 or 5, wherein a plurality of test pistons are provided and wear tests of a plurality of test pieces are simultaneously performed.

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