Method and device combination for detecting content of glue in resistor disc

Abstract

The invention relates to the technical field of resistor disc glue content precision measurement, in particular to a method and device combination for detecting the glue content in a resistor disc. According to the detection method provided by the invention, the glue in the resistor disc can be completely discharged through the specific heat treatment curve, so that the glue content in the resistor disc can be accurately obtained by utilizing the weight difference of the resistor disc before and after heat treatment, and whether the glue content of the same batch of resistor discs meets the standard or not can be accurately deduced; the glue content of the resistor disc can be accurately measured, the problem that an existing method cannot accurately measure the glue content is solved, and the production quality of the resistor disc is improved. The operation is simple, and large-scale production is facilitated; in the measuring process, the resistor disc cannot be damaged, so that the performance of the resistor disc is ensured; the requirement on equipment is low, and high-precision equipment is not needed, so that the production cost is reduced; the glue content can be accurately measured, and the production efficiency and the product quality are improved.

Description

Technical Field

[0001] The invention relates to the technical field of precise measurement of glue content in resistor sheets, and in particular to a detection method and device combination for the glue content in resistor sheets. Background Art

[0002] Resistor is an important pressure-sensitive electronic component, widely used in various electronic devices. The performance of resistor depends mainly on whether its internal components are uniform. Among them, whether the glue in the resistor is completely drained determines the performance of the resistor, so accurate control of the glue content is the key to ensuring the performance of the resistor. However, due to the difficulty in measuring the glue content, traditional measurement methods often cannot obtain accurate results, which brings certain difficulties to the production of resistors.

[0003] The existing methods for testing the adhesive content of resistors are mainly measured by physical or chemical methods. For example, the adhesive content can be measured by weighing, that is, by weighing the weight of the resistor in different states, and then calculating the adhesive content. In addition, the adhesive content can also be measured by a thermogravimetric analyzer, that is, by measuring the weight change curve of the powder due to the volatilization of the substance during the heating process, and then according to the temperature range of the volatile matter of the adhesive, the adhesive content can be obtained.

[0004] However, there are some problems with the existing methods for testing the glue content of resistors. First of all, the first method, the weighing method, cannot accurately measure the glue content because the unstable oxides contained in the resistor will absorb / release oxygen when heated at high temperature in the air, causing the weight of the powder to change. Secondly, the thermogravimetric analysis method can only measure a limited number of substances, and can only obtain reference results. In addition, the thermogravimetric analysis method requires the resistor to be crushed, which will damage the resistor and affect its performance. Therefore, how to accurately, quickly and non-destructively measure the glue content of the resistor is an important problem facing the current resistor manufacturing technology. Summary of the invention

[0005] In view of this, the technical problem to be solved by the present invention is to provide a detection method and device combination for the glue content in a resistor. The detection method provided by the present invention can quickly and accurately measure the glue content in the resistor without causing damage to the resistor. The operation is simple and the equipment requirements are low.

[0006] The present invention provides a method for detecting the glue content in a resistor, comprising the following steps:

[0007] S1) Obtain the weight of the resistor;

[0008] S2) heat-treating the resistor described in step S1) in a protective gas atmosphere, and then obtaining the weight of the resistor after the heat treatment;

[0009] The heat treatment is as follows: heating to 180°C-220°C at a rate of 13°C / min-17°C / min and keeping the temperature for 3 h-4 h, then heating to 230°C-270°C at a rate of 8°C / min-12°C / min and keeping the temperature for 4 h-5 h, then heating to 280°C-320°C at a rate of 6°C / min-10°C / min and keeping the temperature for 6-7 hours, and finally heating to 430°C-470°C at a rate of 3°C / min-7°C / min and keeping the temperature for 5-6 hours;

[0010] S3) obtaining the glue content in the resistor according to the weight of the resistor in step S1) and the weight of the resistor after the heat treatment in step S2);

[0011] The main component of the glue in the resistor is polyvinyl alcohol.

[0012] The detection method provided by the present invention can drain the glue in the resistor through a specific heat treatment curve, so that the weight difference before and after the heat treatment of the resistor can be used to accurately obtain the glue content in the resistor, so as to accurately infer whether the glue content of the same batch of resistors meets the standard. Preferably, the heat treatment is: heating to 190℃~210℃ at a rate of 14℃ / min~16℃ / min and keeping warm for 3.5h~4.5h, then heating to 240℃~260℃ at a rate of 9℃ / min~11℃ / min and keeping warm for 4.5h~5.5h, then heating to 290℃~310℃ at a rate of 7℃ / min~9℃ / min and keeping warm for 6.5~7.5 hours, and finally heating to 440℃~460℃ at a rate of 4℃ / min~6℃ / min and keeping warm for 5.5~6.5 hours. In certain embodiments of the present invention, the heat treatment is: heating to 200°C at a rate of 15°C / min and keeping warm for 4 hours, then heating to 250°C at a rate of 10°C / min and keeping warm for 5 hours, then heating to 300°C at a rate of 8°C / min and keeping warm for 7 hours, and finally heating to 450°C at a rate of 5°C / min and keeping warm for 6 hours.

[0013] The detection method provided by the present invention is aimed at detecting the content of glue whose main component is polyvinyl alcohol in a resistor. Specifically, the glue in the resistor comes from 088-20 brand polyvinyl alcohol. There are differences in the brands of glue formulas of different resistors, and the types of resistor glue are different, and their glue removal temperature curves are also different; this scheme is only applicable to glue whose main component is polyvinyl alcohol, specifically 088-20 brand polyvinyl alcohol.

[0014] The detection method provided by the present invention is aimed at the content of glue in the resistor sheet cannot be too high or too low. If the glue content is too low, it will lead to a large deviation in the test weight loss; if the glue content is too high, it will lead to incomplete glue removal during the heat treatment process, and the glue content cannot be accurately measured. The content of glue in the resistor sheet of the present invention is 0.5%~3%.

[0015] The detection method provided by the present invention first obtains the weight of the resistor. Specifically, the weight of the resistor is obtained immediately after the resistor is dried. More specifically, the resistor is dried, and then the weight of the dried resistor is obtained within 5 minutes. In certain embodiments of the present invention, the resistor is placed on a magnesium oxide board for drying. The drying temperature of the present invention is 110°C~130°C, and the drying time is 2.5 h~3.5 h. After the resistor is dried in the present invention, the weight of the resistor should be obtained immediately, and the sample should not be weighed until it cools down. In certain embodiments of the present invention, a balance is used to weigh the dried resistor to obtain the weight of the dried resistor. The weighing must be performed according to the balance operating specifications. When weighing the dried resistor, a heat insulating pad must be placed to prevent inaccurate weighing.

[0016] After obtaining the weight of the resistor, the present invention performs heat treatment on the resistor in a protective gas atmosphere, and then obtains the weight of the resistor after the heat treatment. Specifically, the resistor is heat treated in a protective gas atmosphere, and then the weight of the resistor after the heat treatment is obtained within 5 minutes. In certain embodiments of the present invention, the resistor is placed on a magnesium oxide board for heat treatment. The protective gas of the present invention is selected from at least one of nitrogen, helium, neon and argon. The heat treatment of the present invention is the same as that described above and will not be repeated. After the heat treatment of the resistor is completed, the weight of the resistor should be obtained immediately, and the weighing should not be performed until the sample cools down. In certain embodiments of the present invention, a balance is used to weigh the resistor after the heat treatment to obtain the weight of the resistor after the heat treatment. The weighing should be performed according to the balance operation specifications. When weighing the resistor after the heat treatment, a heat insulating pad should be placed to prevent inaccurate weighing.

[0017] The present invention further includes filtering the protective gas to remove moisture from the gas before the resistor is subjected to heat treatment. In addition, the present invention further includes washing the protective gas used for heat treatment before the resistor is subjected to heat treatment, specifically, evacuating the protective gas atmosphere and then reintroducing the protective gas, and repeating this process for more than three times.

[0018] After obtaining the weight of the resistor after heat treatment, the present invention obtains the glue content in the resistor according to the weight of the resistor described in step S1) and the weight of the resistor after heat treatment described in step S2). The present invention can accurately obtain the glue content in the resistor by using the weight difference before and after the heat treatment of the resistor. Specifically, the weight difference is obtained by subtracting the weight of the resistor after heat treatment described in step S2) from the weight of the resistor described in step S1), and then the obtained weight difference is compared with the weight of the resistor described in step S1) to obtain the glue content in the resistor. After obtaining the glue content in the resistor, the present invention can perform natural cooling when the temperature drops below 100°C, and continuously introduce protective gas during natural cooling; the resistor is not damaged during the whole process and can still be put into use in other process links.

[0019] The present invention also provides a device combination for applying the detection method described in any of the above technical solutions, including a heat treatment device and a weighing device:

[0020] The heat treatment device comprises:

[0021] Protective gas container;

[0022] a gas filter connected to the gas outlet of the protective gas container;

[0023] a gas flow controller connected to the gas outlet of the gas filter;

[0024] a heating device connected to the gas outlet of the gas flow controller;

[0025] an exhaust device connected to the air outlet of the heating device;

[0026] A vacuum device connected to the air outlet of the heating device.

[0027] The heat treatment device described in the present invention is used to perform heat treatment on the dried resistor sheet in a protective gas atmosphere, wherein the protective gas container is used to store the protective gas, and the protective gas container is provided with an outlet; the gas filter is used to filter the protective gas, and the gas filter is provided with an air inlet and an air outlet, and its air inlet is connected to the air outlet of the gas filter; the gas flow controller is used to control the flow of the protective gas passing through, and the gas flow controller is provided with an air inlet and an air outlet, and its air inlet is connected to the air outlet of the gas filter; the heating device is used to perform heat treatment on the dried resistor sheet, and the heating device is provided with an air inlet and an air outlet, and its air inlet is connected to the air outlet of the gas flow controller; the exhaust device is used to remove the gas in the heating device, and it is connected to the air outlet of the heating device; the vacuum device is used to vacuum the heating device, and it is connected to the air outlet of the heating device. The protective gas stored in the protective gas container of the present invention can be released through the gas outlet, and enter the heating device through the gas filter and the gas flow controller in sequence, so that a protective gas atmosphere is formed in the heating device, and the resistor is heat treated in the heating device.

[0028] The present invention provides a method and device combination for detecting the glue content in a resistor. The detection method provided by the present invention can drain the glue in the resistor through a specific heat treatment curve, so that the weight difference before and after the heat treatment of the resistor can be used to accurately obtain the glue content in the resistor, so that it can accurately infer whether the glue content of the same batch of resistors meets the standard. Compared with the existing technology, the beneficial effects of the technical solution are as follows: 1. Accurate measurement: The technical solution can accurately measure the glue content of the resistor, solving the problem that the traditional test method cannot accurately measure, thereby improving the production quality of the resistor. 2. Simplified operation: The operation of the technical solution is simple. Compared with the physical or chemical methods in the existing technology, there is no need for complicated operation steps, which greatly reduces the difficulty of operation and is conducive to large-scale production. 3. Non-destructive testing: The technical solution will not cause any damage to the resistor during the measurement process, avoiding the damage to the resistor that may be caused by the existing method, thereby ensuring the performance of the resistor. 4. Reduced equipment requirements: The technical solution has lower requirements for equipment. Compared with the existing technology, high-precision equipment is not required, thereby reducing production costs. 5. Guiding production: This technical solution can accurately measure the glue content to guide production, thereby improving production efficiency and product quality.

[0029] The method for detecting the glue content in a resistor provided by the present invention can be widely used in application fields such as resistor manufacturing, electronic equipment production, and precision measurement. First, the technical solution can accurately measure the glue content of the resistor, which is of great significance for improving the performance of the resistor, and all electronic equipment manufacturers who need to use resistors can benefit from it. Secondly, the operation of the technical solution is simple, the requirements for equipment are low, and it is conducive to large-scale production. All manufacturers engaged in resistor manufacturing can adopt this technology. Finally, the measurement accuracy of the technical solution is high and non-destructive. All fields that need to accurately measure the glue content, such as the field of precision measurement technology, can also adopt this technology. In general, the application prospects of the technical solution are broad and the market demand is large. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the heating curve change in Example 1 of the present invention;

[0031] Figure 2 This is a photo of the resistor before debonding;

[0032] Figure 3 This is a photo of the resistor after debonding;

[0033] Figure 4 This is a photo of the resistor of Comparative Example 1 after firing;

[0034] Figure 5 This is a black heart diagram of the resistor's electrical performance test. DETAILED DESCRIPTION

[0035] The present invention discloses a method and device combination for detecting the glue content in a resistor. A person skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve the same. It should be particularly noted that all similar substitutions and modifications are obvious to a person skilled in the art and are considered to be included in the present invention. The method and application of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the method and application of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0036] The present invention detects the glue content of the resistor to be tested according to the following process:

[0037] Dry the sample → weigh → filter the gas → wash the gas → heat according to the heating curve → cool down → weigh → calculate according to the formula;

[0038] The main component of the glue contained in the resistor to be tested in the present invention is: polyvinyl alcohol (PVA) (088-20).

[0039] The present invention will be further described below in conjunction with embodiments:

[0040] Example 1

[0041] 1. Place the resistor on the magnesium oxide board, keep both in a 120℃ oven for 3 hours, and record the weight of the resistor as G1. Weigh the sample immediately after taking it out of the oven, and do not wait until the sample cools down before weighing.

[0042] 2. Before the high-purity inert gas is introduced into the equipment, an air filter is connected in front of it to filter out the moisture in the gas. The composition of the high-purity inert gas is: argon purity: 99.999%, nitrogen: 99.99%

[0043] 3. Place the dried resistor on the magnesium oxide board, put them into the muffle furnace, introduce high-purity nitrogen gas, and keep the atmosphere in the furnace in a nitrogen atmosphere.

[0044] 4. Before introducing the gas, wash the participating gases in the tube, evacuate the tube, and add nitrogen. Repeat this three times to maintain a nitrogen environment.

[0045] 5. Set the following program: 0~200℃ heating rate is 15℃ / min, heating to 200℃ and keeping warm for 4 hours; 200~250℃ heating rate is 10℃ / min, heating to 250℃ and keeping warm for 5 hours; 250~300℃ heating rate is 8℃ / min, heating to 300℃ and keeping warm for 7 hours; 300℃~450℃ heating rate is 5℃ / min, heating to the highest temperature of 450℃ and keeping warm for 6 hours. The heating curve is as follows: Figure 1 As shown, Figure 1 This is a schematic diagram of the heating curve changes in Example 1 of the present invention.

[0046] 6. Weigh the resistor after heat treatment in step 5 and record the weight G2. The sample should be weighed immediately after it is taken out of the atmosphere furnace and should not be weighed after the sample cools down. Calculate the percentage of glue in the resistor according to formula 1:

[0047] Glue content (wt%) = (G1-G2) / G1×100% Formula 1.

[0048] 7. After the insulation time is over, continue to introduce nitrogen. When the temperature drops below 100°C, natural cooling can be carried out.

[0049] Example 2

[0050] 1. Place the resistor on the magnesium oxide board, keep both in a 120℃ oven for 3 hours, and record the weight of the resistor as G1. Weigh the sample immediately after taking it out of the oven, and do not wait until the sample cools down before weighing.

[0051] 2. Before high-purity inert gas is introduced into the equipment, an air filter is connected in front of it to filter out moisture in the gas.

[0052] 3. Place the dried resistor on the magnesium oxide plate, put them into the muffle furnace, introduce high-purity argon gas, and keep the atmosphere in the furnace in argon atmosphere.

[0053] 4. Before introducing the gas, wash the participating gases in the tube, evacuate the tube, and add argon gas. Repeat this three times to maintain the argon environment.

[0054] 5. Set the following program: 0~200℃ heating rate is 15℃ / min, heating to 200℃ and keeping warm for 4 hours; 200~280℃ heating rate is 10℃ / min, heating to 280℃ and keeping warm for 5 hours; 280~310℃ heating rate is 8℃ / min, heating to 310℃ and keeping warm for 7 hours; 310℃~460℃ heating rate is 5℃ / min, heating to the highest temperature of 460℃, keeping warm for 6 hours.

[0055] 6. Weigh the resistor after heat treatment in step 5 and record the weight G2. The sample should be weighed immediately after it is taken out of the atmosphere furnace and should not be weighed after the sample cools down. Calculate the percentage of glue in the resistor according to formula 1 in embodiment 1 above.

[0056] 7. After the insulation time is over, cool naturally and continue to introduce argon. When the temperature drops below 100℃, cool naturally.

[0057] Comparative Example 1

[0058] Based on Example 1, the only difference is that the heating procedure of step 5 is as follows:

[0059] The heating rate from 0 to 200°C is 15°C / min, and the temperature is raised to 200°C and kept for 4 hours; the heating rate from 200 to 250°C is 10°C / min, and the temperature is raised to 250°C and kept for 3 hours; the heating rate from 250 to 450°C is 8°C / min, and the temperature is raised to 450°C and kept for 7 hours.

[0060] The experimental data of the above embodiments and comparative examples are shown in Table 1:

[0061] Table 1

[0062]

[0063] It can be seen from Table 1 that the heating rate is too fast, the holding temperature is too high, and the holding time is too short, resulting in a large difference between the weight loss of the resistor and the theoretical value.

[0064] Since the detection method of the present invention can accurately detect the glue content of the resistor, the glue in the resistor can be accurately drained in the subsequent process, and the subsequent sintering is not damaged. Debinding is one of the necessary processes in the manufacture of resistors. Generally, there is no change in the morphology before and after debinding. Figure 2 and Figure 3 As shown, Figure 2 This is a photo of the resistor before debonding. Figure 3 This is a photo of the resistor after debinding. After debinding the resistor, there is another sintering step. If the debinding is not done completely before, cracking will occur during sintering. The detection method of the present invention can accurately detect the glue content of the resistor, which has a popular significance for the resistors of the same batch.

[0065] In comparative example 1 of the present invention, the heating speed is too fast, the holding temperature is too high, and the holding time is too short, which leads to a large difference between the weight loss of the resistor and the theoretical value, and finally leads to incomplete debonding of the resistor, which leads to cracking after subsequent firing. The electrical performance test of the resistor is black, that is, there is an air interlayer. Figure 4 and Figure 5 As shown, Figure 4 This is a photo of the resistor in comparative example 1 after firing. Figure 5 This is a black heart diagram of the resistor's electrical performance test.

[0066] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for detecting the glue content in a resistor, characterized in that: The following steps are involved: S1) Obtain the weight of the resistor; S2) heat-treating the resistor described in step S1) in a protective gas atmosphere, and then obtaining the weight of the resistor after the heat treatment; The heat treatment is as follows: heating to 180°C-220°C at a rate of 13°C / min-17°C / min and keeping the temperature for 3 h-4 h, then heating to 230°C-270°C at a rate of 8°C / min-12°C / min and keeping the temperature for 4 h-5 h, then heating to 280°C-320°C at a rate of 6°C / min-10°C / min and keeping the temperature for 6-7 hours, and finally heating to 430°C-470°C at a rate of 3°C / min-7°C / min and keeping the temperature for 5-6 hours; S3) obtaining the glue content in the resistor according to the weight of the resistor in step S1) and the weight of the resistor after the heat treatment in step S2); The main component of the glue in the resistor is polyvinyl alcohol.

2. The method for detecting the glue content in a resistor according to claim 1, characterized in that: In step S2), the heat treatment is as follows: heating to 190°C~210°C at a rate of 14°C / min~16°C / min and keeping warm for 3.5 h~4.5 h, then heating to 240°C~260°C at a rate of 9°C / min~11°C / min and keeping warm for 4.5 h~5.5 h, then heating to 290°C~310°C at a rate of 7°C / min~9°C / min and keeping warm for 6.5~7.5 hours, and finally heating to 440°C~460°C at a rate of 4°C / min~6°C / min and keeping warm for 5.5~6.5 hours.

3. The method for detecting the glue content in a resistor according to claim 2, characterized in that: In step S2), the heat treatment is as follows: heating to 200°C at a rate of 15°C / min and keeping warm for 4 h, then heating to 250°C at a rate of 10°C / min and keeping warm for 5 h, then heating to 300°C at a rate of 8°C / min and keeping warm for 7 hours, and finally heating to 450°C at a rate of 5°C / min and keeping warm for 6 hours.

4. The method for detecting the glue content in a resistor according to claim 1, characterized in that: The glue in the resistor sheet is derived from 088-20 brand polyvinyl alcohol.

5. The method for detecting the glue content in a resistor according to claim 1, characterized in that: The content of glue in the resistor is 0.5% to 3%.

6. The method for detecting the glue content in a resistor according to any one of claims 1 to 5, characterized in that: Step S1) specifically includes drying the resistor sheet, and then obtaining the weight of the dried resistor sheet within 5 minutes.

7. The method for detecting the glue content in a resistor according to claim 6, characterized in that: The drying temperature is 110° C. to 130° C., and the drying time is 2.5 h to 3.5 h.

8. The method for detecting the glue content in a resistor according to any one of claims 1 to 5, characterized in that: Step S2) specifically includes: heat-treating the resistor sheet in step S1) in a protective gas atmosphere, and then obtaining the weight of the resistor sheet after the heat treatment within 5 minutes.

9. The method for detecting the glue content in a resistor according to any one of claims 1 to 5, characterized in that: In step S1), the resistor is placed on magnesium oxide for drying; In step S2), the resistor sheet described in step S1) is placed on magnesium oxide for heat treatment.

10. A device combination using the detection method described in any one of claims 1 to 9, characterized in that: Including heat treatment device and weighing device: The heat treatment device comprises: Protective gas container; a gas filter connected to the gas outlet of the protective gas container; a gas flow controller connected to the gas outlet of the gas filter; a heating device connected to the gas outlet of the gas flow controller; an exhaust device connected to the air outlet of the heating device; A vacuum device connected to the air outlet of the heating device.

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