A method for detecting the resistance of a ceramic capacitor to soldering heat

Abstract

A method for detecting the heat resistance of soldering of a ceramic capacitor, comprising the following steps: Step 1, hang one side of the pin end on the support rod in the oven through the first hook; Step 2, then hang the load weight on the other side of the pin end through the second hook, so that the load weight is located below the ceramic capacitor; Step 3, first adjust the temperature of the oven to the limit temperature of the equipment, and then gradually heat up from room temperature to the limit temperature. During the heating process, through the observation hole on the oven, observe the situation of the solder joints on the ceramic capacitor to judge whether the metal sheet is separated from the ceramic chip. If separation occurs, the load weight will fall to the bottom of the oven, and record the temperature of the oven at this time, which is the melting temperature of the solder joints of the ceramic capacitor; Through the defined process steps, the heat resistance of soldering of the ceramic capacitor product can be truly reflected. The overall process is simple and convenient, with high efficiency, and the detection result is accurate and effective.

Description

Technical Field

[0001] The present invention belongs to the field of performance detection of ceramic capacitors, and particularly relates to a method for detecting the heat resistance of soldering of ceramic capacitors. Background Art

[0002] With the development of technology, in fields such as power supply, industry, automotive, military, and aerospace, the demand for large-capacity and high-power capacitors is increasing day by day. However, traditional chip ceramic capacitors are difficult to meet the demand for large capacity. Therefore, multiple ceramic capacitors are assembled in parallel. The parallel assembly is mainly connected by solder. Since there are coatings on the ceramic chip ends and the lead frame, after soldering, the metal components in the coating and the metal components in the solder fuse to form solder joints. At this time, a detection method is needed to evaluate the melting point of the newly formed solder joints.

[0003] The traditional method for evaluating the heat resistance of soldering of capacitor solder joints is mainly to simulate the customer's reflow soldering method: the detection method is to set the temperature in the reflow oven in advance, place the product on the conveyor belt in the reflow oven, and after the product passes through a round of reflow soldering with the conveyor belt, observe whether the solder joints melt, and determine the heat resistance temperature of the solder joints based on the temperature in the highest temperature zone in the reflow oven. This method has many disadvantages. First, when the furnace temperature is set unreasonably, it is very difficult to determine the melting temperature of the solder joints, and it is necessary to adjust the furnace temperature and pass through the furnace multiple times to determine. Second, it is impossible to observe the state of the entire solder joint during the melting process, and further improvement is needed. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a method for detecting the heat resistance of soldering of ceramic capacitors.

[0005] The present invention adopts the following technical solutions:

[0006] A method for detecting the heat resistance of soldering of ceramic capacitors, the ceramic capacitor includes two symmetrically arranged metal sheets and a plurality of ceramic chips stacked between the two metal sheets. The metal sheet includes a metal sheet body and an L-shaped pin end provided at the lower end of the metal sheet body. The detection method includes the following steps:

[0007] Step 1, hang one side of the pin end on the support rod in the oven through the first hook;

[0008] Step 2, then hang the load weight on the other side of the pin end through the second hook, so that the load weight is located below the ceramic capacitor;

[0009] Step 3: First, adjust the oven temperature to the maximum temperature of the equipment, and then gradually increase the temperature from room temperature to the maximum temperature. During the heating process, through the observation hole on the oven, observe the soldering points on the ceramic capacitor to determine whether the metal sheet is separated from the ceramic chip. If separation occurs, the load weight will fall to the bottom of the oven. Record the temperature of the oven at this time, which is the melting temperature of the soldering point of the ceramic capacitor.

[0010] Further, the size of the ceramic capacitor is 1200 - 2250 inches, and the weight of the load weight is 5 - 10 g.

[0011] Further, the first hook includes a first extension rod, a first upper hook portion provided at the top of the first extension rod for cooperating with the support rod, and a first lower hook portion provided at the bottom of the first extension rod for cooperating with a pin end.

[0012] Further, the second hook includes a second extension rod, a second upper hook portion provided at the top of the second extension rod for cooperating with the other pin end, and a second lower hook portion provided at the bottom of the second extension rod for cooperating with the load weight.

[0013] Further, a third hook portion for cooperating with the second lower hook portion is formed at the top of the load weight.

[0014] Further, the first upper hook portion and the second upper hook portion are in an inverted L shape, and the first lower hook portion and the second lower hook portion are in an L shape.

[0015] As can be seen from the above description of the present invention, compared with the prior art, the beneficial effects of the present invention are as follows: By defining the detection steps for the soldering heat resistance of the ceramic capacitor, the ceramic capacitor is suspended in the oven, and a load weight with a defined weight is suspended at the bottom of the ceramic capacitor. With the gradually increasing temperature in the oven, when the load weight drops, the temperature displayed in the oven at this time is the melting temperature of the soldering point of the ceramic capacitor. Through the defined process steps, the soldering heat resistance performance of the ceramic capacitor product can be truly reflected. The overall process is simple, convenient, efficient, and the detection result is accurate and effective. Description of the Drawings

[0016] Figure 1 It is a schematic structural diagram of the soldering heat resistance detection device;

[0017] Figure 2 It is a schematic structural diagram of the ceramic capacitor;

[0018] Figure 3 It is a schematic structural diagram of the load weight;

[0019] In the figure, 1 - oven, 2 - support rod, 3 - first hook, 4 - second hook, 5 - load weight, 6 - ceramic capacitor, 11 - observation hole, 31 - first extension rod, 32 - first upper hook part, 33 - first lower hook part, 41 - second extension rod, 42 - second upper hook part, 43 - second lower hook part, 51 - third hook part, 61 - metal sheet, 62 - ceramic chip, 63 - metal sheet body, 64 - pin end. Detailed implementation mode

[0020] The present invention will be further described below through specific implementation modes.

[0021] Refer to Figures 1 to 3 As shown, a device for detecting the heat resistance of soldering of a ceramic capacitor includes an oven 1, a support rod 2 arranged in the oven 1, a first hook 3 arranged on the support rod 2 for hanging the ceramic capacitor 6, a second hook 4 hanging downward on the ceramic capacitor 6, and a load weight 5 arranged on the second hook 4; specifically, the size of the ceramic capacitor 6 detected in this application is 1200 - 2250 inches, and the weight of the load weight 5 is 5 - 10 g.

[0022] The ceramic capacitor 6 includes two symmetrically arranged metal sheets 61 and a plurality of ceramic chips 62 stacked between the two metal sheets 61; specifically, the metal sheet 61 includes a metal sheet body 63 and a pin end 64 arranged at the lower end of the metal sheet body 63; further, the pin end 4 is L-shaped, which is convenient for hanging the ceramic capacitor 6 and the load weight 5, and the hanging of the ceramic capacitor 6 and the load weight 5 can be completed without taking any measures on the ceramic capacitor 6, and the operation is convenient.

[0023] The oven 1 is provided with a transparent observation hole 11 for real-time detection of the detection situation in the oven 1.

[0024] The support rod 2 is fixed on the side wall of the oven 1 for hanging the ceramic capacitor 6 for detection.

[0025] The first hook 3 includes a first extension rod 31, a first upper hook part 32 arranged at the top of the first extension rod 31 and cooperating with the support rod 2, and a first lower hook part 33 arranged at the bottom of the first extension rod 31 and cooperating with a pin end 64; specifically, the first upper hook part 32 is L-shaped inverted, and the first lower hook part 33 is L-shaped, so as to hang the ceramic capacitor 6 on the support rod 2 through the first hook 3.

[0026] The second hook 4 includes a second extension rod 41, a second upper hook portion 42 disposed at the top of the second extension rod 41 and cooperating with the other pin end 64, and a second lower hook portion 43 disposed at the bottom of the second extension rod 41 and cooperating with the load weight 5. Specifically, the second upper hook portion 42 is in an inverted L shape, and the second lower hook portion 43 is in an L shape, so as to hang the load weight 5 on the second hook 4 via the second hook 4.

[0027] The load weight 5 has a third hook portion 51 formed at the top and cooperating with the second lower hook 43.

[0028] A method for detecting the soldering heat resistance of a ceramic capacitor specifically includes the following steps:

[0029] Step 1: Hang one pin end 64 of the ceramic capacitor 6 on the support rod 2 in the oven 1 via the first hook 3.

[0030] Step 2: Then hang the load weight 5 on the other pin end 64 via the second hook 4, so that the load weight 5 is located below the ceramic capacitor 6.

[0031] Step 3: First, adjust the temperature of the oven 1 to the limit temperature of the device, and then gradually increase the temperature from room temperature to the limit temperature. During the heating process, through the observation hole 11 on the oven 1, observe the soldering points on the ceramic capacitor 6 to judge whether the metal sheet 61 is separated from the ceramic chip 62. If separation occurs, the load weight 5 will fall to the bottom of the oven 1, and record the temperature of the oven 1 at this time, which is the melting temperature of the soldering points of the ceramic capacitor 6.

[0032] Among them, the limit temperature of the oven 1 is 300 °C. The sizes of the ceramic capacitors 6 detected in this application are 1206 inches, 1210 inches, 1812 inches, and 2220 inches, and the relative weights of the load weights 5 are 5 g, 5 g, 10 g, and 10 g.

[0033] In this application, by defining the detection steps for the soldering heat resistance of the ceramic capacitor, the ceramic capacitor 6 is hung in the oven 1, and a load weight 5 with a defined weight is hung at the bottom of the ceramic capacitor 6. Combining with the gradually increasing temperature in the oven 1, when the load weight 5 drops, the temperature displayed in the oven 1 at this time is the melting temperature of the soldering points of the ceramic capacitor 6. Through the defined process steps, the soldering heat resistance performance of the ceramic capacitor 6 product can be truly reflected. The overall process is simple, convenient, efficient, and the detection results are accurate and effective.

[0034] The above is only a preferred embodiment of the present invention, and thus cannot limit the scope of implementation of the present invention. That is, equivalent changes and modifications made according to the scope of the patent application of the present invention and the content of the specification should still fall within the scope covered by the patent of the present invention.

Claims

1. A method for detecting the heat resistance of soldering of a ceramic capacitor, characterized in that: The ceramic capacitor includes two symmetrically arranged metal sheets and a plurality of ceramic chips stacked between the two metal sheets. The metal sheet includes a metal sheet body and an L-shaped pin end provided at the lower end of the metal sheet body. Its detection method includes the following steps: Step 1: Hang one pin end on the support rod in the oven through the first hook. Step 2: Then hang the load weight on the other pin end through the second hook, so that the load weight is located below the ceramic capacitor. Step 3: First, adjust the oven temperature to the limit temperature of the equipment, and then gradually heat up from room temperature to the limit temperature. During the heating process, through the observation hole on the oven, observe the solder joints on the ceramic capacitor to judge whether the metal sheet and the ceramic chip are separated. If separation occurs, the load weight will fall to the bottom of the oven, and record the temperature of the oven at this time, which is the solder melting temperature of the ceramic capacitor. The size of the ceramic capacitor is 1200 - 2250 inches, and the weight of the load weight is 5 - 10 g.

2. The method for detecting the resistance of a ceramic capacitor to soldering heat according to claim 1, wherein: The first hook includes a first extension rod, a first upper hook portion provided at the top of the first extension rod for cooperating with the support rod, and a first lower hook portion provided at the bottom of the first extension rod for cooperating with one pin end.

3. A method for detecting the thermal resistance to soldering of a ceramic capacitor according to claim 2, characterized in that: The second hook includes a second extension rod, a second upper hook portion provided at the top of the second extension rod for cooperating with the other pin end, and a second lower hook portion provided at the bottom of the second extension rod for cooperating with the load weight.

4. A method for detecting the thermal resistance to soldering of a ceramic capacitor according to claim 3, characterized in that: A third hook portion for cooperating with the second lower hook portion is formed on the top of the load weight.

5. The method for detecting the heat resistance of soldering of a ceramic capacitor according to claim 3, characterized in that: The first upper hook portion and the second upper hook portion are in an inverted L shape, and the first lower hook portion and the second lower hook portion are in an L shape.

Images