JP2021118335A - Electronic component - Google Patents

Abstract

To provide an electronic component that can suppress the influence of a fuse when a lead terminal is joined.SOLUTION: An electronic component 100 includes a base body 2 having a rectangular parallelepiped shape and having a pair of end faces facing each other, a pair of main faces facing each other, and a pair of side faces facing each other, a pair of external electrodes 3 provided on the pair of end faces, a pair of lead terminals 20 bonded to the pair of external electrodes 3, and a fuse 40 provided in one lead terminal 20. The pair of lead terminals 20 includes a pair of joints 21 joined to the pair of external electrodes 3 and a pair of extending portions 22 extending from the pair of joints 21 to one side in a first direction D1 in which the pair of main faces face each other. The fuse 40 is located on one side of the base body 2.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to electronic components.

Patent Document 1 describes an electronic component including a capacitor and a fuse. Since the fuse is blown by the overcurrent, it is possible to prevent the overcurrent from flowing through the capacitor.

Jitsukaisho 62-23435

In the above electronic components, a fuse is arranged on the end face of the capacitor together with the lead terminal. Therefore, when joining the lead terminal to the capacitor, the fuse may be affected.

One aspect of the present disclosure provides an electronic component capable of suppressing the influence of a fuse when joining lead terminals.

The electronic component according to one aspect of the present disclosure has a rectangular parallelepiped shape, and has a base body having a pair of end faces facing each other, a pair of main surfaces facing each other, and a pair of side surfaces facing each other, and a pair of end faces. A pair of external electrodes provided in the above, a pair of lead terminals bonded to the pair of external electrodes, and a fuse provided in one lead terminal are provided, and the pair of lead terminals are bonded to the pair of external electrodes. The fuse has a pair of joints and a pair of extension portions extending from the pair of joints to one side in the first direction in which a pair of main surfaces face each other, and the fuse is on one side of the element body. Is located in.

In this electronic component, the fuse provided in one lead terminal is located on one side of the element body in the first direction in which the pair of main surfaces face each other. Therefore, it is possible to suppress the influence of the fuse when joining the lead terminals.

The pair of extending portions has a pair of changing regions in which the distance between the pair of end faces changes in the opposite second direction toward one side, and the pair of changing regions are spaced toward one side. It has a pair of first change regions that are widened, a pair of second change regions that are narrower toward one side, and a pair of third change regions that are wider toward one side. , The pair of first change regions, the pair of second change regions, and the pair of third change regions are arranged in this order from the pair of joints, and the fuse is provided in the change region of one lead terminal. Has been done. In this case, a joining member such as solder is unlikely to accumulate between the main surface of the body and the pair of lead terminals. Therefore, it is possible to suppress the stress applied to the fuse by the accumulated joining member.

The pair of extension portions is provided on one side of the pair of change regions, further includes a pair of mount portions mounted on the mounting board, and the fuse is provided in the first change region in one lead terminal. You may. In this case, since the fuse is provided in the first change region farthest from the mounting board in the changing region, it is possible to suppress the stress from the mounting board from being applied to the fuse.

The electronic component may further include a cover covering the fuse. In this case, the fuse can be protected and damage to the fuse can be suppressed.

The electronic component may further include at least a body, a pair of external electrodes, and an exterior resin covering the pair of joints. In this case, at least the element body, the pair of external electrodes, and the pair of joints can be protected and their damage can be suppressed.

The exterior resin may cover the fuse via a cover. In this case, damage to the fuse can be further suppressed.

The exterior resin does not have to cover the fuse. In this case, the range in which the exterior resin is formed can be reduced. As a result, the amount of resin used as the material for the exterior resin can be reduced.

The cover may be made of a part of the exterior resin. In this case, the fuse can be easily covered.

According to one aspect of the present disclosure, it is possible to provide an electronic component capable of suppressing the influence of the fuse when joining the lead terminals.

FIG. 1 is a side view of an electronic component according to the first embodiment. FIG. 2 is a diagram showing a cross-sectional configuration of the electronic component of FIG. FIG. 3 is a perspective view of the main body. FIG. 4 is a side view of the electronic component according to the second embodiment. FIG. 5 is a side view of the electronic component according to the third embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are designated by the same reference numerals, and duplicate description will be omitted.

(First Embodiment)
FIG. 1 is a side view of an electronic component according to the first embodiment. FIG. 2 is a diagram showing a cross-sectional configuration of the electronic component of FIG. FIG. 3 is a perspective view of the main body. As shown in FIGS. 1 and 2, the electronic component 100 according to the first embodiment includes a main body 1, a pair of lead terminals 20, a fuse 40, an exterior resin 50, and a cover 60. .. In FIG. 1, the exterior resin 50 and the cover 60 are shown by broken lines. In FIG. 2, the exterior resin 50 is not shown.

The electronic component 100 is a so-called radial read type electronic component. The electronic component 100 is mounted on the mounting board 101, for example, by inserting a pair of lead terminals 20 into a pair of through holes 101a provided on the mounting board 101. The mounting board 101 is, for example, a printed circuit board.

The main body 1 is, for example, a multilayer capacitor. The main body 1 includes a body 2, a pair of external electrodes 3 arranged on the outer surface of the body 2, and internal electrodes 4 and 5 arranged inside the body 2.

The element body 2 has a rectangular parallelepiped shape. The rectangular parallelepiped shape includes a rectangular parallelepiped shape in which the corners and ridges are chamfered, and a rectangular parallelepiped in which the corners and ridges are rounded. The element body 2 has a pair of end faces 2a facing each other, a pair of main faces 2b facing each other, and a pair of side surfaces 2c facing each other as its outer surface. The facing direction in which the pair of main surfaces 2b face each other is the first direction D1. The facing direction in which the pair of end faces 2a face each other is the second direction D2. The facing direction in which the pair of side surfaces 2c face each other is the third direction D3. In the present embodiment, the first direction D1 is the height direction of the element body 2. The second direction D2 is the longitudinal direction of the element body 2 and is orthogonal to the first direction D1. The third direction D3 is the width direction of the element body 2 and is orthogonal to the first direction D1 and the second direction D2.

The pair of end faces 2a extend in the first direction D1 so as to connect between the pair of main faces 2b. The pair of end faces 2a also extends in the third direction D3. The pair of side surfaces 2c extend in the first direction D1 so as to connect between the pair of main surfaces 2b. The pair of side surfaces 2c also extends in the second direction D2. In the present embodiment, one main surface 2b is defined as a facing surface facing the other electronic component when the electronic component 100 is mounted on another electronic device (for example, a circuit board or an electronic component). ..

The length (height) of the element body 2 in the first direction D1 is, for example, 0.2 mm or more and 5.0 mm or less. The length (length) of the element body 2 in the second direction D2 is, for example, 0.4 mm or more and 10.0 mm or less. The length (width) of the element body 2 in the third direction D3 is, for example, 0.2 mm or more and 8.0 mm or less.

The element body 2 is configured by laminating a plurality of dielectric layers (insulator layers) in opposite directions in which a pair of main surfaces 2b face each other. In the element body 2, the stacking direction of the plurality of dielectric layers (hereinafter, simply referred to as “stacking direction”) coincides with the first direction D1. Each dielectric layer is from a sintered body of a ceramic green sheet containing, for example, a dielectric material (a dielectric ceramic such as BaTiO ₃ series, Ba (Ti, Zr) O ₃ series, or (Ba, Ca) TiO _{3 series).} It is composed. In the actual element body 2, each dielectric layer is integrated to such an extent that the boundary between the respective dielectric layers cannot be visually recognized.

The pair of external electrodes 3 are separated from each other in the second direction D2. The pair of external electrodes 3 are arranged on the end surface 2a side of the element body 2, that is, at the end portion of the element body 2 in the second direction D2. The external electrode 3 has an electrode portion 3a arranged on the end surface 2a, a pair of electrode portions 3b arranged on the pair of main surfaces 2b, and a pair of electrode portions 3c arranged on the pair of side surface 2c. is doing. That is, the external electrodes 3 are formed on five surfaces: one end surface 2a, a pair of main surfaces 2b, and a pair of side surfaces 2c. The electrode portions adjacent to each other are connected at the ridge portion of the element body 2 and are electrically connected to each other.

The electrode portion 3a is arranged so as to cover all the portions exposed to the end faces 2a of the corresponding internal electrodes 4 and 5, and the internal electrodes 4 and 5 are directly connected to the electrode portions arranged on the end faces 2a. Has been done. As a result, the internal electrodes 4 and 5 are electrically connected to the corresponding external electrodes 3.

The external electrode 3 has, for example, a first electrode layer provided on the element body 2 and a second electrode layer provided on the first electrode layer, respectively. That is, each electrode portion 3a, 3b, 3c of the external electrode 3 includes a first electrode layer and a second electrode layer. The second electrode layer constitutes the outermost layer of the external electrode 3.

The first electrode layer is formed by applying a conductive paste to the surface of the element body 2 and baking it. The first electrode layer is a sintered metal layer formed by sintering a metal component (metal powder) contained in the conductive paste. That is, the first electrode layer is a sintered metal layer formed on the element body 2. In the present embodiment, the first electrode layer is a sintered metal layer made of Cu. The first electrode layer may be a sintered metal layer made of Ni. As described above, the first electrode layer contains Cu or Ni. As the conductive paste, a powder made of Cu or Ni mixed with a glass component, an organic binder, and an organic solvent is used.

The second electrode layer is formed on the first electrode layer by a plating method. The second electrode layer includes, for example, a Ni plating layer formed on the first electrode layer and a Sn plating layer formed on the Ni plating layer.

The internal electrodes 4 and 5 are made of a conductive material usually used as an internal electrode of a laminated electric element. As the conductive material, a base metal (for example, Ni or Cu) is used. The internal electrodes 4 and 5 are configured as a sintered body of a conductive paste containing the above conductive material. In this embodiment, the internal electrodes 4 and 5 are made of Ni.

The internal electrode 4 and the internal electrode 5 are arranged at different positions (layers) in the first direction D1. That is, the internal electrodes 4 and the internal electrodes 5 are alternately arranged in the element body 2 so as to face each other with a gap in the first direction D1. The internal electrodes 4 and 5 have different polarities from each other. The internal electrode 4 has an end connected to one of the external electrodes 3. The internal electrode 5 has an end connected to the other external electrode 3.

The pair of lead terminals 20 is not particularly limited as long as it is a conductive metal material, and is formed of, for example, Cu or Fe, or an alloy containing these. The lead terminal 20 may have a plating layer on its surface.

The pair of lead terminals 20 are arranged so as to face the pair of end faces 2a. The pair of lead terminals 20 are separated from each other in the second direction D2. The pair of lead terminals 20 are joined to the pair of external electrodes 3 by the joining member 30. The joining member 30 has conductivity, and electrically and physically connects the pair of lead terminals 20 and the pair of external electrodes 3. The joining member 30 is provided, for example, so as to cover the entire outer surface of the external electrode 3 and a part of the pair of lead terminals 20.

The joining member 30 is, for example, solder or a conductive adhesive (conductive resin layer). The conductive adhesive is composed of, for example, a resin such as a thermosetting resin and a conductive filler such as Ag. As the thermosetting resin, for example, a phenol resin, an acrylic resin, a silicone resin, an epoxy resin, a polyimide resin, or the like is used. For example, the joining member 30 may be formed by joining the pair of lead terminals 20 to the external electrode 3 with cream solder and then dipping (immersing) the main body 1 together with the pair of lead terminals 20 in the molten solder.

The pair of lead terminals 20 are a pair of joining portions 21 joined to the pair of external electrodes 3 and a pair of extending portions extending from the pair of joining portions 21 to one side (mounting board 101 side) in the first direction D1. It has a part 22 and.

The joint portion 21 includes one end in the length direction of the lead terminal 20. The joint portion 21 is formed, for example, having a substantially semicircular cross section, and has a rectangular flat surface portion 21a. The joint portion 21 is arranged so that the flat surface portion 21a faces the end surface 2a. The flat surface portion 21a is electrically and physically joined to the electrode portion 3a by the joining member 30.

The extending portion 22 is formed in a circular cross-sectional shape concentric with the joining portion 21 and having the same diameter. Therefore, the joint portion 21 has a step portion 21b between the joint portion 21 and the extending portion 22. The step portion 21b has, for example, a substantially semicircular shape. The step portion 21b faces the main surface 2b on the mounting board 101 side of the pair of main surfaces 2b. Of the pair of electrode portions 3b, the step portion 21b is electrically and physically joined to the electrode portion 3b on the mounting substrate 101 side by the joining member 30. The entire outer surface of the joint portion 21 is covered with the joint member 30.

A part of the outer surface of the extending portion 22 on the joining portion 21 side is covered with the joining member 30. The other portion of the outer surface of the extending portion 22 is exposed from the joining member 30. The pair of extending portions 22 has a pair of changing regions R and a pair of mounting portions 23. In the pair of change regions R, the distance between them in the second direction D2 changes toward the mounting substrate 101 side. The change region R is provided on the joint portion 21 side of the mounting portion 23.

The pair of change regions R includes a pair of first change regions R1, a pair of second change regions R2, and a pair of third change regions R3. The pair of first change regions R1, the pair of second change regions R2, and the pair of third change regions R3 are arranged in this order from the pair of joints 21 side. That is, in the change region R, the third change region R3 is arranged closest to the mounting substrate 101. The second change region R2 is arranged between the first change region R1 and the third change region R3.

In the pair of first change regions R1, the distance between them in the second direction D2 increases toward the mounting substrate 101 side. In the pair of second change regions R2, the distance between them in the second direction D2 becomes narrower toward the mounting substrate 101 side. In the pair of third change regions R3, the distance between them in the second direction D2 increases toward the mounting substrate 101 side. The change region R is configured by bending the lead terminal 20. That is, a bent portion is formed between the first change region R1 and the second change region R2. A bent portion is formed between the second change region R2 and the third change region R3.

The mounting portion 23 is provided on the mounting board 101 side with respect to the change region R. The mounting unit 23 is mounted on the mounting board 101. The mounting portion 23 includes a portion to be inserted through the through hole 101a. The mounting portion 23 is joined to the mounting substrate 101 by a joining member such as solder in a state of being inserted into the through hole 101a, for example.

The fuse 40 is provided to prevent an overcurrent from flowing through the main body 1. The fuse 40 is provided at one lead terminal 20 of the pair of lead terminals 20. The fuse 40 may be provided at at least one lead terminal 20. The fuse 40 may be provided on both of the pair of lead terminals 20. When an overcurrent flows through one lead terminal 20, the fuse 40 is blown, so that the overcurrent is suppressed from flowing through the main body 1.

The operating temperature of the fuse 40 is set according to the upper limit of the temperature at which the main body 1 can be used. The operating temperature of the fuse 40 is set to, for example, 100 ° C. or higher and 200 ° C. or lower. The fuse 40 is made of, for example, a metal material having a low melting point that easily melts at an operating temperature. The fuse 40 is made of, for example, a metal material such as solder or lead. The fuse 40 may have, for example, a structure that easily melts at an operating temperature. Specifically, the fuse 40 may be configured to have a cross-sectional area smaller than that of the lead terminal 20. The smaller the cross-sectional area, the easier it is to melt.

The fuse 40 is located on one side (mounting board 101 side) in the first direction D1 with respect to the element body 2. Of the pair of main surfaces 2b, the fuse 40 is located on the mounting board 101 side in the first direction D1 with respect to the main surface 2b on the mounting board 101 side. The fuse 40 is provided in the change region R of one lead terminal 20. More specifically, the fuse 40 is provided in the first change region R1 in one lead terminal 20. The fuse 40 is provided so as to form a part of the first change region R1 in one lead terminal 20. It can be said that one lead terminal 20 has a fuse 40 as a part of the first change region R1. The fuse 40 is provided at the lead terminal 20 by thermocompression bonding, for example.

The exterior resin 50 is made of, for example, an insulating resin such as nitrile rubber or epoxy resin. The exterior resin 50 has a first portion 51 having a rectangular parallelepiped shape, and a pair of second portions 52 protruding from the first portion 51 along the pair of lead terminals 20. The first portion 51 and the pair of second portions 52 are continuous with each other and integrally formed. The first portion 51 covers and seals the main body 1, a part of the pair of lead terminals 20, and the joining member 30. The first portion 51 is the joining member 30, the entire portion of the main body 1 exposed from the joining member 30, and a part of the pair of lead terminals 20 exposed from the joining member 30 (that is, the extending portion 22). It is provided so as to be in contact with each of them. The exterior resin 50 directly or indirectly covers the main body 1 and the pair of joints 21 via a joint member 30 or the like.

Each second portion 52 covers a part of each extending portion 22 (at least a portion including a part of each first change region R1). The length of the pair of second portions 52 covering the pair of first change regions R1 is equal to each other. In the pair of first change regions R1, the lengths of the portions covered by the pair of second portions 52 are equal to each other.

The cover 60 is made of, for example, nitrile rubber or an insulating resin such as an epoxy resin. The cover 60 is made of, for example, the same material as the exterior resin 50. The cover 60 covers the entire outer peripheral surface of the fuse 40. The cover 60 is provided so as to be in contact with the outer peripheral surface of the fuse 40. The cover 60 directly covers the outer peripheral surface of the fuse 40. The cover 60 is covered with a second portion 52 of the exterior resin 50. That is, the exterior resin 50 indirectly covers the fuse 40 via the cover 60.

In one lead terminal 20, the cover 60 covers a part of the extending portion 22 (here, a part of the first change region R1) adjacent to the fuse 40. In one lead terminal 20, the second portion 52 is provided so as to be in contact with a part of the portion of the first change region R1 exposed from the cover 60. In one lead terminal 20, the cover 60 and the second portion 52 do not reach the second change region R2. The second change region R2 and the third change region R3 are exposed from the cover 60 and the exterior resin 50. Also in the other lead terminal 20, the second change region R2 and the third change region R3 are exposed from the exterior resin 50.

Hereinafter, the effects of the electronic component 100 will be described.

In the electronic component 100, the fuse 40 provided in one lead terminal 20 is located closer to the mounting substrate 101 than the element body 2 in the first direction D1 in which the pair of main surfaces 2b face each other. Therefore, for example, when solder is used as the joining member 30 and the lead terminal 20 is joined to the external electrode 3 of the main body 1, the influence of heat on the fuse 40 can be suppressed. Therefore, it is possible to prevent the fuse 40 from being blown at the time of joining.

The pair of extending portions 22 have a pair of changing regions R whose distances from each other in the second direction D2 change toward the mounting substrate 101 side. The pair of change regions R is a pair of first change regions R1 in which the distance between them is widened toward the mounting board 101 side, and a pair of second change regions R1 in which the distance between them is narrow toward the mounting board 101 side. It has R2 and a pair of third change regions R3 whose distances from each other are widened toward the mounting substrate 101 side. The pair of first change regions R1, the pair of second change regions R2, and the pair of third change regions R3 are arranged in this order from the pair of joints 21 side. The fuse 40 is provided in the change region R of one lead terminal 20. Of the pair of change regions R, the pair of first change regions R1 are provided closest to the pair of joints 21. In the pair of first change regions R1, the distance between them increases toward the mounting substrate 101 side. Therefore, the joining member 30 is unlikely to accumulate between the main surface 2b on the mounting board 101 side and the pair of lead terminals 20. Therefore, it is possible to suppress the stress caused by the accumulated joining member 30 from being applied to the fuse 40. In particular, the shrinkage stress generated when the joining member 30 solidifies can be suppressed.

The pair of extending portions 22 are provided on the mounting board 101 side with respect to the pair of changing regions R, and have a pair of mounting portions 23 mounted on the mounting board 101. The fuse 40 is provided in the first change region R1 of one lead terminal 20. As described above, since the fuse 40 is provided in the first change region R1 of the change region R farthest from the mounting board 101, it is possible to suppress the stress from the mounting board 101 from being applied to the fuse 40.

The electronic component 100 includes a cover 60 that covers the fuse 40. Therefore, the fuse 40 can be protected and damage to the fuse 40 can be suppressed. The electronic component 100 includes at least the main body 1 and the exterior resin 50 that covers the pair of joints 21. Therefore, at least the main body 1 and the pair of joints 21 can be protected and their damage can be suppressed. The exterior resin 50 covers the fuse 40 via the cover 60. Therefore, damage to the fuse 40 can be further suppressed.

(Second Embodiment)
FIG. 4 is a side view of the electronic component according to the second embodiment. In FIG. 4, the exterior resin 50 is shown by a broken line. The electronic component 100A according to the second embodiment shown in FIG. 4 will be described focusing on the difference from the electronic component 100 according to the first embodiment.

The electronic component 100A does not include the cover 60. The exterior resin 50 directly covers the fuse 40 without passing through the cover 60. That is, in the present embodiment, the cover covering the fuse 40 is composed of a part of the exterior resin 50 (specifically, one second part 52).

In the electronic component 100A as well, since the fuse 40 is located closer to the mounting substrate 101 than the element body 2, the effect of heat on the fuse 40 when the lead terminal 20 is joined to the external electrode 3 of the main body 1 is affected. It can be suppressed. The cover covering the fuse 40 is made of a part of the exterior resin 50. Therefore, the fuse 40 can be easily covered without providing a cover separate from the exterior resin 50.

(Third Embodiment)
FIG. 5 is a side view of the electronic component according to the third embodiment. In FIG. 5, the exterior resin 50 is shown by a broken line. The electronic component 100B according to the third embodiment shown in FIG. 5 will be described focusing on the difference from the electronic component 100 according to the first embodiment.

In the electronic component 100B, the exterior resin 50 does not have a pair of second portions 52 that cover the cover 60. That is, the exterior resin 50 does not indirectly cover the fuse 40. The cover 60 is provided so as to be in contact with the first portion 51. In the present embodiment, the end portion of the cover 60 on the first portion 51 side is provided so as to overlap with the first portion 51. Therefore, the lead terminal 20 is not exposed between the first portion 51 and the cover 60.

Even in the electronic component 100B, since the fuse 40 is located closer to the mounting substrate 101 than the element body 2, the influence of heat on the fuse 40 when the lead terminal 20 is joined to the external electrode 3 of the main body 1 is affected. It can be suppressed. The exterior resin 50 does not cover the fuse 40. Therefore, the range in which the exterior resin 50 is formed can be reduced.

Although the embodiments of the present invention have been described above, the present invention is not necessarily limited to the above-described embodiments, and various modifications can be made without departing from the gist thereof.

In the present embodiment, a multilayer capacitor has been described as an example of the main body 1, but the main body 1 is not limited to the multilayer capacitor. The main body 1 is, for example, a laminated electronic component such as a laminated inductor, a laminated varistor, a laminated piezoelectric actuator, a laminated thermistor, or a laminated composite component, or an electronic component other than the laminated electronic component.

1 ... Main body, 2 ... Elementary body, 3 ... External electrode, 20 ... Lead terminal, 21 ... Joint part, 22 ... Extension part, 23 ... Mounting part, R ... Change area, R1 ... First change area, R2 ... No. Two change regions, R3 ... third change region, 40 ... fuses, 50 ... exterior resins, 60 ... covers, 100, 100A, 100B ... electronic components, 101 ... mounting boards.

Claims (8)

A body having a rectangular parallelepiped shape and having a pair of end faces facing each other, a pair of main faces facing each other, and a pair of side surfaces facing each other.
A pair of external electrodes provided on the pair of end faces and
A pair of lead terminals bonded to the pair of external electrodes and
A fuse provided in one of the lead terminals is provided.
The pair of lead terminals includes a pair of joints joined to the pair of external electrodes and a pair of extensions extending from the pair of joints to one side in the first direction in which the pair of main surfaces face each other. With a part,
The fuse is an electronic component located on one side of the element body. The pair of extending portions has a pair of changing regions in which the distance between the pair of end faces in the opposite second direction changes toward one side.
The pair of change regions includes a pair of first change regions whose spacing is widened toward one side, a pair of second change regions whose spacing is narrower toward one side, and the one side. It has a pair of third change regions, the interval of which increases toward
The pair of first change regions, the pair of second change regions, and the pair of third change regions are arranged in this order from the pair of joints.
The electronic component according to claim 1, wherein the fuse is provided in the change region of the one lead terminal. The pair of extending portions further include a pair of mounting portions provided on one side of the pair of changing regions and mounted on a mounting board.
The electronic component according to claim 2, wherein the fuse is provided in the first change region of the one lead terminal. The electronic component according to any one of claims 1 to 3, further comprising a cover covering the fuse. The electronic component according to claim 4, further comprising at least the element body, the pair of external electrodes, and an exterior resin covering the pair of joints. The electronic component according to claim 5, wherein the exterior resin covers the fuse via the cover. The electronic component according to claim 5, wherein the exterior resin does not cover the fuse. The electronic component according to claim 5, wherein the cover is made of a part of the exterior resin.

Images