Powder mass measuring device and powder mass measuring method

Abstract

To provide an apparatus and method for uniformly depositing dust or other powder onto a test specimen and quantitatively measuring the amount of the deposited powder. [Solution] The powder mass measuring device 1 is installed in a dust fall test apparatus in which dust or other powders fall naturally with a uniform distribution. The powder mass measuring device 1 comprises a test specimen 3 into which the powder falls, a stand 4 that horizontally supports the test specimen 3, a mass measuring unit 5 that measures the mass of the powder accumulated on the test specimen 3, and a cover 6 that houses the stand 4 and the mass measuring unit 5.

Description

Technical Field

[0001] The present invention relates to a technique for quantitatively measuring powders such as dust deposited on a specimen.

Background Art

[0002] Various tests are being conducted as performance evaluation tests for electronic devices and other devices. For example, a dustfall test based on JIS standards (JIS C 60068-2-68) is known. Further, Patent Document 1 discloses a dust evaluation test apparatus that drops fibrous particles generated by rubbing and cutting a base material of a fibrous substance in a housing onto a test specimen as a test apparatus for evaluating the influence of fibrous particles on a test specimen.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is a method of utilizing an ACM (Atmospheric Corrosion Monitor) type corrosion sensor (hereinafter referred to as an ACM sensor) in order to optimize the inspection period within a panel. The ACM sensor outputs a galvanic current [A] as immediate data and an electric quantity [C] as integrated data. In particular, the electric quantity [C] is correlated with the amount of sea salt deposition, corrosion rate, etc., which are related to problems within the panel. The purpose of inspection within the panel is to prevent insulation breakdown and corrosion due to dust deposition, but it is unknown at what level of deposition problems will occur.

[0005] Therefore, by confirming the relationship between the deposition amount and the output value of the ACM sensor while changing the type, content components, etc. of dust in a test environment, an appropriate inspection period under the target actual environment can be obtained.

[0006] Furthermore, in order to determine the relationship between the output value of the ACM sensor and the amount of dust accumulation, it is necessary to quantitatively measure the amount of dust accumulation.

[0007] However, while the dust deposition test based on the aforementioned JIS standard defines the deposition rate of dust and sand, it does not suggest any method for measuring the actual mass of accumulated sand and dust.

[0008] Furthermore, the dust evaluation test apparatus described in Patent Document 1 is intended to uniformly deposit fibrous particles onto a test specimen, and does not perform a quantitative evaluation of the fibrous particles deposited on the test specimen.

[0009] This invention has been made in view of the above circumstances, and its objective is to provide an apparatus and method that can uniformly deposit powder such as dust onto a test specimen and quantitatively measure the amount of the deposited powder. [Means for solving the problem]

[0010] One aspect of the present invention is a powder mass measuring device comprising a test specimen from which powder is dropped, a stand that horizontally supports the test specimen, a mass measuring unit that measures the mass of the powder accumulated on the test specimen, and a cover that houses the stand and the mass measuring unit.

[0011] One aspect of the present invention is a powder mass measuring device, wherein the mass measuring unit calculates the stacked mass of the powder per unit area of ​​the test specimen based on the measured mass of the powder and the area of ​​the test specimen on which the powder is deposited.

[0012] One aspect of the present invention is a powder mass measuring device, wherein the mass measuring unit calculates the thickness of the powder layer based on the layered mass of the powder per unit area and the density of the powder.

[0013] One aspect of the present invention is a method for measuring the mass of a powder, comprising a stand for horizontally supporting a test specimen and a mass measuring unit for measuring the mass of the powder, housed within a cover, wherein the powder is lowered and the mass of the powder deposited on the test specimen is measured by the mass measuring unit. [Effects of the Invention]

[0014] According to the present invention described above, powder can be uniformly deposited on a test specimen, and the amount of deposited powder can be quantitatively measured. [Brief explanation of the drawing]

[0015] [Figure 1] A schematic diagram of the powder mass measuring device according to Embodiment 1 of the present invention. [Figure 2] A schematic diagram of the ACM sensor configuration. [Figure 3] A characteristic diagram showing the relationship between the powder deposition thickness in the ACM sensor and the output value of the ACM sensor. [Modes for carrying out the invention]

[0016] Embodiments of the present invention will be described in detail below.

[0017] [Embodiment 1] The powder mass measuring device 1, which is one embodiment of the present invention shown in Figure 1, is installed in a dust fall test device in which powder such as dust falls naturally with a uniform distribution.

[0018] The powder mass measuring device 1 comprises a test specimen 3 from which the powder descends, a stand 4 that horizontally supports the test specimen 3, a mass measuring unit 5 that measures the mass of the powder accumulated on the test specimen 3, and a cover 6 that houses the stand 4 and the mass measuring unit 5.

[0019] Test specimen 3 consists of a plate-shaped member, and an ACM sensor 2 is installed on its surface.

[0020] The ACM sensor 2 is a sensor in which an insulating layer 23 is interposed between a substrate 21 and a conductive layer 22 as shown in FIG. 2, and the ACM sensor 2 detects a galvanic current [A] in which the powder adheres to and flows on its surface.

[0021] The galvanic current [A] is output as real-time data, and the electrical quantity [C] based on the galvanic current [A] is output as integrated data to the sensing unit 7. The sensing unit 7 evaluates the dielectric breakdown and corrosiveness due to the deposition of the powder based on the electrical quantity [C] received from the ACM sensor 2.

[0022] The cover part 6 is made of a material such as a transparent resin that houses the gantry part 4 and the mass measurement part 5 so that the powder does not enter the mass measurement part 5 and allows the mass measurement part 5 to be visually confirmed. In addition, the outer surface of the cover part 6 may be coated with a fluororesin or the like to prevent the adhesion of the powder. Further, when the mass data measured by the mass measurement part 5 is acquired by wire, a hole part for inserting a communication cable is formed in the cover part 6. This hole part is hermetically sealed with a fluororesin tape or the like after the communication cable is inserted during the test implementation.

[0023] Hereinafter, the operation and effect of the present embodiment will be described.

[0024] In the powder mass measuring device 1, the powder descends onto the specimen 3 by free fall. The specimen 3 is horizontally held by the gantry part 4, and since the deposition concentration of the powder on a part of the specimen 3 due to the inclination of the specimen 3 is avoided, the powder is uniformly deposited on the upper surface of the specimen 3. The mass of the powder deposited on the specimen 3 is measured by the mass measurement part 5.

[0025] According to the powder mass measuring device 1 of the above-described embodiment 1, the mass of the powder can be measured in a state where the powder is uniformly deposited on the specimen 3 by ensuring that the specimen 3 is horizontal. Further, since the gantry part 4 and the mass measurement part 5 are housed in the cover part 6, the mixing of powder from the outside can be prevented, so that the mass of the powder can be accurately measured.

[0026] [Embodiment 2] In the embodiment of Embodiment 2, the powder mass measuring device 1 measures the stacked mass of the powder per unit area of ​​the test specimen 3 as an indicator for quantitatively evaluating the powder.

[0027] In other words, in Embodiment 1, the mass measuring unit 5 uniformly deposits the powder on the upper surface of the test specimen 3, and then calculates the amount of the powder deposited per unit area of ​​the test specimen 3 based on the measured mass of the powder and the area of ​​the test specimen 3 on which the powder is deposited. More specifically, the amount of the powder deposited per unit area of ​​the test specimen 3 is calculated by dividing the measured mass of the powder by the area.

[0028] According to the powder mass measuring device 1 of Embodiment 2 described above, by dividing the mass of the powder uniformly deposited on the test specimen 3 in Embodiment 1 by the area of ​​the test specimen 3, in addition to the effects of Embodiment 1, the amount of the powder deposited per unit area of ​​the test specimen 3 can be accurately measured.

[0029] [Embodiment 3] The powder mass measuring device 1 of Embodiment 3 is further capable of measuring the thickness of the powder deposit as an indicator for quantitative evaluation of the powder, in accordance with the embodiment of Embodiment 2.

[0030] In a sensor with a laminated structure of a conductive layer 22 and an insulating layer 23, such as the ACM sensor 2 shown in Figure 2, the thickness of the powder deposition is important because it affects the conductivity between the conductive layer 22 and the insulating layer 23. Therefore, quantitatively evaluating the thickness of the powder deposition is useful.

[0031] Therefore, in Embodiment 2, the mass measuring unit 5 calculates the stacked mass of the powder per unit area of ​​the test specimen 3, and then calculates the stacked thickness of the powder based on the density of the powder.

[0032] The density of the aforementioned powder is the density of the powder deposited using a dust-collecting test apparatus, and is calculated in advance through a preliminary test. In this preliminary test, a graduated cylinder or beaker is placed inside the dust-collecting test apparatus, and powder simulating dust is deposited inside. Then, the volume and mass of the deposited powder are measured after removing it from the dust-collecting test apparatus. The density of the powder is then calculated based on these measured volume and mass.

[0033] According to Embodiment 3 described above, the thickness of the powder deposit can be calculated based on the mass of the powder per unit area calculated in Embodiment 2 and the density of the powder calculated in advance. As a result, the sensing unit 7 can evaluate whether the thickness of the powder deposit on the test specimen 3 exceeds the thickness of each layer (for example, the insulating layer 23 or the conductive layer 22 laminated on the insulating layer 23) based on the amount of power [C] detected by the ACM sensor 2.

[0034] Figure 3 is a characteristic diagram showing the relationship between the powder deposition thickness [mm] and the output value (electrical quantity [C]) of the ACM sensor 2 obtained by the embodiment of this present invention. As is clear from this characteristic diagram, a correlation was confirmed between the powder deposition thickness and the output value of the ACM sensor 2.

[0035] Therefore, according to the powder mass measuring device 1 of Embodiment 3, when applied in a real environment such as inside a control panel, it is possible to determine how much dust accumulation will cause equipment malfunction, and thus prevent dielectric breakdown and corrosion inside the control panel due to dust accumulation. [Explanation of Symbols]

[0036] 1…Powder mass measuring device 2…ACM sensor, 21…Substrate, 22…Conductive layer, 23…Insulating layer 3...Specimen 4…Support structure 5…Mass measurement unit 6...Cover part 7...Sensing Department

Claims

1. A test specimen from which powder falls, This test specimen has a horizontal support structure, A mass measuring unit for measuring the mass of the powder deposited on the specimen, The base portion and the cover portion that houses the mass measuring unit A powder mass measuring device characterized by being equipped with the following features.

2. The mass measuring unit calculates the stacked mass of the powder per unit area of ​​the test specimen based on the measured mass of the powder and the area of ​​the test specimen on which the powder is deposited. The powder mass measuring device according to claim 1, characterized by the following:

3. The mass measuring unit calculates the thickness of the powder layer based on the layered mass of the powder per unit area and the density of the powder. The powder mass measuring device according to claim 2, characterized by the following:

4. A method for measuring the mass of a powder, characterized in that a stand for horizontally supporting a test specimen and a mass measuring unit for measuring the mass of a powder are housed within a cover, and the powder is lowered and the mass of the powder deposited on the test specimen is measured by the mass measuring unit.

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