JPS5911615A - Case sheathing type electronic part - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] The present invention comprises a case in which a metallized plastic film capacitor element or a composite electronic component element including a metallized plastic film capacitor element is housed in a case 7, and a synthetic resin is divided into 21 parts and filled 7. The hardness of the case exterior electronic components, especially the two synthetic resin layers, should be appropriately selected.1.
O Concerning case-mounted electronic components that have an internal pressure explosion-proof function.Multiple sheets of metallized plastic film, which is made by vapor-depositing metal on plastic film, are laminated and wound, and the electronic components and other electronic components are connected to each other and housed in the case. , the electrode of the case-exposed plastic film capacitor element filled with synthetic resin is about 0.02 to 0.1 μm @1. Since it is a thin vapor-deposited metal layer, dielectric breakdown occurs at the electrically weak points of the plastic film, causing partial discharge. Since the electrode has excellent so-called self-healing properties, in which the electrode melts and scatters due to discharge energy and recovers its insulation properties, it is widely used for noise prevention in various electronic devices and commercial power supplies.

However, even though this metallized plastic film capacitor element has an excellent self-healing function, if it is exposed to abnormally high temperatures for a long time during use, or if excessive pressure is not applied for a long time, the plastic may deteriorate. Due to deterioration of the film, the withstand voltage decreases (7) and the frequency of occurrence of partial dielectric breakdown increases [17] The deterioration of the plastic film is further accelerated by the increase in partial discharge and heat generation that accompanies fidgeting, and the breakdown progresses. , the self-recovery function described above is completely short-circuited and l
However, a certain resistance value leads to the ultimate destruction of Jikonji Temple. Therefore, in this state, a safety device connected to the external circuit, such as a heater or a breaker, may be activated.The plastic film is decomposed due to subsequent partial discharges, and gas is generated, and this gas enters the case-mounted electronic components. It will be full. On the other hand, epoxy resin is mainly used as the filling resin for case-mounted electronic components due to its electrical, environmental characteristics, workability, and cost. The internal pressure increases due to the decomposition gas, which eventually causes the filled resin and the outer case to explode, damaging equipment that incorporates case-mounted electronic components.
Furthermore, there was a risk that the gas could ignite and cause a fire.

As a countermeasure against this problem, case-exposed electronic components with various security structures have been devised. For example, a metalized plastic film capacitor element or a composite electronic component element including a metalized plastic film capacitor element is sealed in a metal case. There is a method of storing the capacitor and disconnecting it from the power supply by cutting the lead wire of the element using the expansion of the case due to gas pressure, or as shown in Fig. A first layer 5 which is housed in an exterior case 4 and filled with epoxy resin covers the element 2゜3, and a further first layer 5.
As shown in FIG. 3, the second layer 6 is separated from the first layer 1-5 by the pressure of the gas to release the gas. A method of cutting the lead wire 7 at the boundary between the two layers to cut off the supply to the elements 2 and 6, and a method of cutting the lead wire 7 at the boundary between the two layers by cutting the two resin layers 5, In order to facilitate the peeling of the two resin layers 5.6, a separator 11 such as insulating paper or polyester film is interposed at the interface 8 between the two resin layers, and a lead wire is provided at the interface 8 between the two resin layers 5.6. 7
For example, as shown in FIG. 2, a mechanically weak portion 10 is formed by making a cut, etc., and when the second resin layer 6 is separated,
A device in which the lead wire 7 can be easily cut has been proposed.

However, in the method that utilizes the expansion of the metal case,
The structure of the case is complicated in order to achieve airtightness, and in the method of using a two-layer structure of filled resin, it is difficult to separate the layers unless the internal pressure increases considerably due to the adhesive force between the resin layers. Cases that can withstand this are severely limited by their materials and structures, and structures in which a separator is interposed between resin layers have the disadvantage of complicating the manufacturing process.

The present invention was devised to solve the above-mentioned drawbacks, and an object of the present invention is to provide a case-exposed electronic component that has a simple structure, is easy to manufacture, and has an excellent explosion-proof function.

In order to achieve the above objectives, we focused on the filling structure and hardness of synthetic resin, and as a result of various studies, we created a two-layer structure for the filling resin.
And the hardness of the filled resin layer on the bottom side of the case is JI8 630
If the hardness of the filling resin layer on the case opening side is set to 90 or higher as specified in Section 1, the boundary surface of both filling resin layers will not peel off when the metallized plastic film capacitor element breaks. The present invention has found that a composite electronic component element including a film capacitor element or a metallized plastic film capacitor element is housed in an exterior case with an opening on one side, and that an explosion can be easily prevented. In a case-exposed electronic component, in which a first filled resin layer is formed to cover the element, and a second filled resin layer is formed at the case opening to cover the first filled resin layer, the first filled resin layer is formed. The hardness of the layer is JI8 to 6
301, and the hardness of the second filled resin layer is selected to be 90 or higher.

An embodiment of the present invention will be described below based on the drawings.

FIG. 4 shows a case-exterior type lightning element component according to an embodiment of the present invention, in which 1 is a case-exterior type electronic component, 2 is a metallized plastic film capacitor element, 3 is an electronic component element, 411 - indicates an exterior case, 5 indicates a first filled resin layer, and 6 indicates a second filled resin layer. Only 12,
The case-exterior type electronic component 1 has a metallized plastic film capacitor element 2 connected to another electronic component element (a fixed resistor in this example) 5, and is made of polyphenyline oxide, polyethylene terephthalate, polybutylene terephthalate, etc. The lead wire 7 is led out from the opening of the case 4 and housed in a plastic case 4 made of synthetic resin, and the synthetic resin is filled in two layers, a first layer 5 and a second layer 6. ing. The first filled resin layer 5 covers the elements 2 and 3, and is JIS K630
The second filled resin layer 6 is made of a soft polyurethane-based synthetic resin having an A hardness of 80 or less as defined in Section 1, and the second filled resin layer 6 is made of a hard synthetic resin such as polyurethane or epoxy that has an A hardness of 90 or more. 5 is filled after curing to cover the first filled resin layer 5 and seal the opening of the outer case 4. Furthermore, the upper surface of the first filled resin layer 5 is the same as that of the case 4.
The second filled resin layer 6 has a curved surface that is higher at the part that contacts with it and lower at the center, and the lower surface of the second filled resin layer 6 is higher than the first filled resin layer 5.
The upper surface has a curved surface having the same shape as that of the case 4, with the upper surface being higher at the part where it contacts the case 4 and lower at the central part. Therefore, the shape of the boundary surface 8 between both filled resin layers 5 and 6 is also the shape described above. This is because when the case 4 is held horizontally and the synthetic resin is filled from the opening, the synthetic resin wets the case 4 and the synthetic resin shrinks during curing.

If the metallized plastic film capacitor element 2 is destroyed due to abnormal high temperature, excessive voltage, etc. acting on the case-exposed electronic component 1 having such a structure, the metallized plastic film capacitor element 2 may be destroyed due to the decomposition of the plastic film as shown in FIG. The gas 9 filled between the metal-plastic film capacitor element 2 and the first filling resin layer 5 increases the internal pressure, but due to the heat generated by the destruction of the metal-plastic film capacitor element 2, the first filling resin layer The layer 5 softens and expands like a balloon, pushing up the second filled resin layer 6 and closing the case 4.
Then, it is peeled off from the first filled resin layer 5, and the internal pressure is lowered while blocking the outside air. In this case, as the lead wire 7,
For example, those with low mechanical strength, double-filled resin RF45,
6, the mechanical strength of at least the 8 portions of the boundary surface 8 is reduced by peeling off the second filled resin layer B. If a wire selected to have a strength that allows it to be cut is used, the boundary surface 8 between both filling resin layers 5 and 6 of the lead wire 7 will be cut and softened by the heat generated by the destruction of the electrons 2 to the case-exposed electronic component 1. However, in order for it to swell due to gas pressure, its hardness must be less than A hardness 80 specified in J18 and 6301. Furthermore, in this example, polyurethane-based synthetic resin is used as the filling resin. The unique viscosity of polyurethane makes the above action easier. In addition, in order for the second filled resin layer 6 to peel off from the case 4 and the first filled resin layer 5 without being softened by the heat generation and hardly deformed even when the first filled resin layer 5 is pushed up, , its hardness is JI8 6501
In addition, in this embodiment, the shape of the interface 8 between the first filled resin layer 5 and the second filled resin layer 6 is high at the part where it contacts the outer case 4. Due to the low curved shape in the central part, the peeling action can be carried out very easily.

As described above, the case-exterior type electronic component of the present invention has a two-layer structure of filled resin, and the first filled resin covers the composite electronic component element including the metallized plastic film capacitor element or the metallized plastic film capacitor element. The hardness of the layer is JI8 6301 and the specified A hardness 80
Since the hardness of the second filled resin layer is selected to be 90 or higher, there is no need to use a special material or structure for the outer case, and it is possible to use two layers of synthetic resin. With a simple manufacturing method that requires only separate filling, it is possible to reliably lower the internal pressure and avoid explosion when a metallized plastic container is destroyed.

[Brief explanation of the drawing]

Fig. 1 is a schematic cross-sectional view of a conventional case-exterior type electronic component, Fig. 2 is an enlarged cross-sectional view showing a case where a mechanically weak part is formed in the lead wire at the interface of the filled resin layer, and Fig. 3 is a schematic cross-sectional view of a conventional case-exterior type electronic component. FIG. 4 is a schematic cross-sectional view of a case-exposed electronic component according to an embodiment of the present invention, and FIG. FIG. 5 is a schematic cross-sectional view showing a state in which the explosion-proof mechanism of the case-exposed electronic component shown in FIG. 4 is in operation. DESCRIPTION OF SYMBOLS 1... Case exterior type electronic component 2... Metal-plastic film capacitor element 3... Electronic component element 4... Exterior case 5... First filled resin layer 6... Second filled resin layer

Claims (2)

[Claims] (1) A composite electronic component element including a metallized plastic film capacitor element or a metallized plastic film capacitor element is housed in an exterior case having an opening on one side, and a first filled resin layer covering the element is provided. In case-exposed electronic components in which a second filled resin layer is formed at the case opening to cover the first filled resin layer, the hardness of the first filled resin layer is A hardness specified in JIS K6301. 80 or less, and the hardness of the second filled resin layer is selected to be 90 or more. (2) Claim 1, characterized in that the shape of the boundary surface between the first filled resin layer and the second filled resin layer is a curved surface that is higher in the part that contacts the outer case and lower in the central part. Claim 1, characterized in that (3) the first filled resin layer is a polyurethane-based synthetic resin.
Case exterior type electronic component as described in item 2 or Fi item 2.