JPH0951178A - Electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic component which has a metal case which supports and holds a board and allows low manufacturing cost. SOLUTION: A metal case 2 is provided with side walls 4-7, which are formed by extending a bottom wall part 3 upward, and holding parts 8 and 9. The holding pats 8 and 9 are provided with spring characteristic which uses metal elasticity. When a board 11 is assembled to the metal case 2, the bottom plane edge parts of the board 11 abut on the top edge planes 41-7a of the side wall parts 4-7 of the metal case 2, and the board 11 is supported by the metal case 2 in the condition that the board 11 is placed horizontally on its side. Then, the holding parts 8 and 9 are permitted to elastically make contact with both edge planes of the board 11. Namely, the board 11 is held between the holding parts 8 and 9 by their spring force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic parts, especially
The present invention relates to an electronic component having a metal case.

[0002]

2. Description of the Related Art Conventionally, as this type of electronic component, an electronic component 65 having a structure shown in FIG. 12 has been known. The electronic component 65 includes a metal case 66 and a substrate 75. The metal case 66 includes a bottom wall portion 67 and side wall portions 68 and 6.
It consists of 9, 70, 71 and convex portions 72, 73. The board 75 has cutouts 77 and 78 at both ends, and an electric functional element (not shown) is mounted on the lower surface.

Then, the protrusions 72 and 73 are inserted into the notches 77 and 78, respectively, to regulate the positional displacement of the substrate 75, and the substrate 75 and the metal case 66 are combined. That is, the upper end surfaces 68 a to 71 a of the side wall portions 68 to 71 of the metal case 66 abut against the lower surface edges of the substrate 75 to support the substrate 75, and the electric function element is accommodated in the metal case 66 through the opening 74. .

Apart from this, an electronic component 81 having a structure shown in FIG. 13 is also known. The electronic component 81 includes a metal case 82 and a substrate 91. The metal case 82 includes a bottom wall portion 83, a side wall portion 84, and ribs 85 and 86 provided on a pair of inner wall surfaces of the side wall portion 84 facing each other. The substrate 91 has external electrodes 93 and 94 at both ends, and an electric functional element (not shown) is mounted on the lower surface. Then, by inserting the substrate 91 from the opening 87 of the metal case 82, the ribs 85 and 86 are brought into contact with both end portions of the lower surface of the substrate 91 while the positional displacement of the substrate 91 is regulated by the side wall portion 84. Support.

[0005]

However, as shown in FIG.
Also, the electronic components 65 and 81 shown in FIG. 13 have various problems listed below.

(1) It is necessary to provide the substrate 75 with the cutouts 77, 78 or the metal case 82 with the ribs 85, 86, and these processes are one of the causes of an increase in manufacturing cost. (2) The metal cases 66 and 82 only support the substrates 75 and 91 and cannot hold them.
If the metal cases 66, 82 and the boards 75, 91 are turned upside down before joining the boards 6, 82 and the boards 75, 91, respectively, the boards 75, 91 will come off the metal cases 66, 82. (3) The effective space of the substrate 75 is reduced by the amount of the cutouts 77 and 78.

Therefore, an object of the present invention is to provide an electronic component which has a metal case capable of supporting and holding a substrate and which is inexpensive to manufacture.

[0008]

In order to achieve the above object, an electronic component according to the present invention comprises (a) a substrate on which an electric functional element is mounted, and (b) an electric functional element mounted on the substrate. A metal case having an opening for accommodating, a pair of holding portions elastically contacting both end faces of the substrate, and a side wall portion supporting the substrate at the end faces. . Here, the electric functional element housed in the metal case may be at least a part of the electric functional element mounted on the substrate.

[0009]

With the above construction, the substrate is supported by the side wall of the metal case and is held by the spring force of the pair of holding portions.
Therefore, even if the board and the metal case are turned upside down before the board and the metal case are joined and fixed with an adhesive or the like, there is no fear that the board and the metal case will come off. Further, even if mechanical vibration or the like is applied from the outside to the electronic component, the position of the substrate does not shift with respect to the metal case, so that the assemblability is improved. In addition, the notch of the substrate and the rib of the metal case, which are required in the conventional electronic component, are not required.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of an electronic component according to the present invention will be described with reference to the accompanying drawings. In each embodiment, the same parts and the same parts are designated by the same reference numerals. [First Embodiment, FIGS. 1 to 3] As shown in FIG. 1, an electronic component 1 is composed of a metal case 2 and a substrate 11.
The metal case 2 includes a bottom wall portion 3, side wall portions 4, 5, 6, 7 extending upward from the bottom wall portion 3 and holding portions 8, 9. The opening portion 10 is formed by the side wall portions 4 to 7 and the holding portions 8 and 9.
Is stipulated. The holding portions 8 and 9 are set to have a predetermined length and have a spring property utilizing metal elasticity. The metal case 2 is formed by punching a metal plate into a predetermined shape and then bending it. That is, the holding portions 8 and 9 are formed in the same step as the side wall portions 4 to 7, and do not require a special processing step. The holding portions 8 and 9 and the side wall portions 4 and 5 are bent in the same plane.

The substrate 11 is an alumina substrate, a printed circuit board,
A multilayer ceramic substrate or the like, in which ground electrodes 13 are provided at the front and rear ends, and signal electrodes 12 are provided at the left and right sides. These electrodes 1
Reference numerals 2 and 13 are of a surface mounting type and enable the electronic component 1 to be surface mounted. On the lower surface of the substrate 11, an electric functional element 14 (see FIG. 2) such as an IC, a semiconductor capacitor and a coil is mounted.

Then, the distance between the outer surfaces of the side walls 4 and 5 of the metal case 2 (the length of the metal case 2 in the first embodiment) is L1, and the distance between the outer surfaces of the side walls 6 and 7 (first In the case of the embodiment, the width of the metal case 2) is W1, the distance between the facing inner surfaces of the holding portions 8 and 9 is L2, and the length of the substrate 11 is L.
3, when the width is W2, the conditional expression L2 <L3 is satisfied, and at least the conditional expression L1 <L3 or the conditional expression W1 <
The respective dimensions L1 to L3, W1 and W2 are set so as to satisfy one of the conditional expressions W2. In the first embodiment, the conditional expressions L2 <L3, the conditional expressions L1 <L3, and the conditional expressions W1 <W2 are all set to be satisfied.

Next, a method of assembling the above-mentioned components 2 and 11 will be described with reference to FIGS. As shown in FIG. 2, a force in the direction of arrow a is applied to the holding portions 8 and 9 of the metal case 2 to widen the distance L2 between the facing inner side surfaces of the holding portions 8 and 9. Next, with the inter-plane distance L2 widened, the substrate 11
Is brought closer to the metal case 2 from the arrow b, and the electric functional element 14 mounted on the lower surface of the substrate 11 is attached to the opening 1 of the metal case 2.
It accommodates 0. Then, according to the conditional expression L1 <L3 and the conditional expression W1 <W2, the length L3 of the substrate 11 is larger than the distance L1 between the outer side surfaces of the side walls 4 and 5 of the metal case 2,
Moreover, since the width W2 of the substrate 11 is larger than the distance W1 between the outer surfaces of the side walls 6 and 7, the lower surface edge of the substrate 11 has the side walls 4 and 5 of the metal case 2 and the upper end surface 4a of the side walls 6 and 7. , 5
a, 6a, 7a. In this way, the substrate 11 is supported horizontally by the metal case 2 in a horizontal state.

Next, when the force applied to the holding portions 8 and 9 is released, the spring characteristics of the holding portions 8 and 9 cause the holding portions 8 and 9 to return to their original state. However, the conditional expression L2
<L3 is a distance L between the inner surfaces of the holding portions 8 and 9 facing each other.
Since the length L3 of the substrate 11 is larger than 2, the face-to-face distance L2 cannot return to the original size, and the holding portions 8 and 9 are provided on both end faces of the substrate 11 as shown in FIG. The ground electrodes 13 are in elastic contact with each other. That is, the substrate 11 is sandwiched by the spring force of the holding portions 8 and 9. Therefore, even if mechanical vibration or the like is externally applied to the electronic component 1 before the board 11 and the metal case 2 are joined and fixed with solder or a conductive adhesive, the position of the board 11 is relative to the metal case 2. Since it is not displaced, a good assembling property can be obtained.

Next, the ground electrode 13 and the holding portions 8 and 9 are soldered, the ground electrode 13 and the holding portions 8 and 9 are electrically connected by the solder 15, and the substrate 11 and the metal case 2 are joined. , Fixed. Since the metal case 2 is electrically connected to the ground electrode 13, it has an electromagnetic shielding property, and the electric functional element 14 housed in the metal case 2 is provided.
Electromagnetic waves emitted from the device are less likely to leak to the outside of the electronic component 1.

The electronic component 1 thus obtained does not require the formation of a notch in the substrate and the ribs of the metal case, which are conventionally required, and the number of manufacturing steps can be reduced. In addition, since the substrate 11 is not provided with the cutout portion, there is no fear that the effective space of the substrate 11 is reduced accordingly. Further, when the electronic component 1 is mounted on the printed wiring board 16 indicated by a chain double-dashed line in FIG. 3, the electronic component 1 temporarily attached to the printed wiring board 16 is reflowed with the metal case 2 down. Suppose At this time, even if the solder 15 that joins the metal case 2 and the substrate 11 is remelted, the holding portions 8 and 9 are not removed.
Since the metal case 2 is elastically contacted with both end surfaces of the metal case 2 and is locked to the substrate 11 with a sufficient force, there is no risk of the metal case 2 falling off.

[Second Embodiment, FIGS. 4 to 6] As shown in FIG. 4, the electronic component 21 is composed of a substrate 11 and a metal case 22. The substrate 11 is the same as that described in the first embodiment. The metal case 22 includes a bottom wall portion 23 and side wall portions 24 extending upward from the bottom wall portion 23,
25 and holding portions 26 and 27. Side wall parts 24, 25
Both ends of each of the side walls 2 are bent at right angles.
An opening 28 is defined by 4, 25 and holding portions 26, 27. The holding portions 26, 27 are set to have a predetermined length and have a spring property utilizing metal elasticity. The metal case 22 is formed by punching a metal plate into a predetermined shape and then bending it. That is, the holding portions 26 and 27 are formed in the same process as the side wall portions 24 and 25,
No special processing steps are required. The holding portions 26 and 27 are disposed inside both ends of the side wall portions 24 and 25.

Then, the side walls 24 and 2 of the metal case 22.
5, the distance between the outer surfaces of both ends (the length of the metal case 22 in the second embodiment) is L1, and the distance between the outer surfaces of the side wall portions 24 and 25 (the width of the metal case 22 in the second embodiment). ) Is W1, and the distance between the facing inner surfaces of the holding portions 26 and 27 is L2.
When the length of the substrate 11 is L3 and the width is W2, the conditional expression L2 <L3 is satisfied, and at least the conditional expression L
The respective dimensions L1 to L3, W1 and W2 are set so as to satisfy one of the conditional expressions 1 <L3 or W1 <W3 or W1 <W2. In the second embodiment, the conditional expression L2 <L3, the conditional expression L1 <L3, and the conditional expression W1.
<W2 is set so as to be satisfied.

As a result, as shown in FIG. 5, the first
When the substrate 11 is assembled to the metal case 22 by the same method as the assembling method described in the embodiment, the conditional expression L
By 1 <L3 and conditional expression W1 <W2, the metal case 22
The length L3 of the substrate 11 is larger than the distance L1 between the outer surfaces of the side walls 24 and 25 at both ends, and the side walls 24 and 2 are
Since the width W2 of the substrate 11 is larger than the outer surface distance W1 of 5, the lower surface edge of the substrate 11 contacts the upper end surfaces 24a and 25a of the side wall portions 24 and 25. In this way, the substrate 11 is supported by the metal case 2.

Further, according to the conditional expression L2 <L3, the substrate 11 is calculated from the distance L2 between the inner surfaces of the holding portions 26 and 27 facing each other.
Since the length L3 is larger, the holding portions 26 and 27 elastically contact the ground electrodes 13 provided on both end surfaces of the substrate 11, respectively, as shown in FIG. That is,
The substrate 11 is sandwiched by the spring force of the holding portions 26 and 27. The ground electrode 13 and the holding portions 26 and 27 are electrically connected by the solder 30, and the substrate 11 and the metal case 22 are joined and fixed. The electronic component 21 has the same effects as the electronic component 1 of the first embodiment.

[Third Embodiment, FIGS. 7 and 8] As shown in FIG. 7, the electronic component 36 is an electronic component 21 of the second embodiment.
Similarly, the substrate 11 and the metal case 22 are included. However, the difference from the electronic component 21 of the second embodiment is that the holding portions 37 and 38 are arranged outside the both ends of the side wall portions 24 and 25. That is, the holding portions 37 and 38 are bent at an acute angle with respect to the bottom wall portion 23. Then, the side wall portions 24, 2 of the metal case 22
L1 is the distance between the outer surfaces of both end portions of 5, the distance between the outer surfaces of the root portions of the holding portions 37 and 38 (the length of the metal case 22 in the third embodiment) is L4, and the tips of the holding portions 37 and 38 are When the distance between the inner surfaces facing each other is L5 and the length of the substrate 11 is L3, the respective dimensions L1, L3, L4 and L5 are set so as to satisfy the conditional expression L5 <L1 <L3 <L4. It

Thus, as shown in FIG. 8, when the substrate 11 is assembled in the metal case 22, the conditional expression L5 <L is satisfied.
3, the length L3 of the substrate 11 is larger than the distance L5 between the facing inner surfaces of the tip portions of the holding portions 37 and 38. Therefore, the holding portions 37 and 38 are provided on the ground electrodes on both end surfaces of the substrate 11. 13 and elastically contact with each other. That is, the substrate 11 is sandwiched by the spring force of the holding portions 37 and 38. At this time, the conditional expression L3 <L
4, the length L3 of the substrate 11 is smaller than the distance L4 between the outer surfaces of the root portions of the holding portions 37 and 38.
1 is located inside the outer periphery of the metal case 22. Therefore, the length and width of the product are always defined by the external dimensions of the metal case 22, and the accuracy of the external dimensions can be improved in addition to the effect of the electronic component 21 of the second embodiment. The ground electrode 13 and the holding portions 37 and 38 are electrically connected by solder 40, and the substrate 11 and the metal case 22 are joined and fixed.

[Fourth Embodiment, FIGS. 9 to 11] As shown in FIG. 9, an electronic component 51 is composed of a substrate 11 and a metal case 52. The substrate 11 is the same as that described in the first embodiment. The metal case 52 includes a bottom wall portion 53 and a side wall portion 5 extending upward from the bottom wall portion 53.
4, 55, 56, 57 and the holding portions 58, 59 extending upward from the upper end portions of the side wall portions 54, 55. Side wall 5
The opening 60 is defined by 4 to 57. Holding part 5
When an external force is applied to 8, 59, the side walls 54, 55 are also curved integrally with the holding parts 58, 59.
Has a spring property utilizing the metal elasticity of itself and the side wall portions 54 and 55.

The side walls 56, 5 of the metal case 52 are
7 outer surface distance (in the case of the fourth embodiment, the metal case 5
2), the distance between the opposing inner side surfaces of the holding portions 58 and 59 is L2, the length of the substrate 11 is L3, and the width is W2, the conditional expressions L2 <L3 and W1 <W2 are satisfied. The respective dimensions L2, L3, W1 and W2 are set so as to be satisfied.

As a result, when the substrate 11 is assembled to the metal case 52 as shown in FIG. 10, the conditional expression W1 <
Since the width W2 of the substrate 11 is larger than the distance W1 between the outer side surfaces of the side wall portions 56 and 57 due to W2, the lower edge portion of the substrate 11 contacts the upper end surfaces 56a and 57a of the side wall portions 56 and 57. In this way, the substrate 11 is supported by the metal case 52.

Further, according to the conditional expression L2 <L3, the substrate 11 is calculated from the distance L2 between the inner surfaces of the holding portions 58 and 59 facing each other.
Since the length L3 is larger, the holding portions 58 and 59 elastically contact the ground electrodes 13 provided on both end faces of the substrate 11, respectively, as shown in FIG. That is, the substrate 11 is sandwiched by the holding portions 58 and 59. At this time, the holding portions 58 and 59 sandwich the substrate 11 by the force of the spring force of the side wall portions 54 and 55 in addition to the spring force of the holding portions 58 and 59. The ground electrode 13 and the holding portions 58 and 59 are electrically connected by solder 60, and the substrate 11
And the metal case 52 are joined and fixed. This electronic component 51 has the same effects as the electronic component 1 of the first embodiment.

[Other Embodiments] The electronic component according to the present invention is not limited to the above-mentioned embodiment, and can be variously modified within the scope of the gist thereof. In the above embodiment, electrodes are provided on both ends of the substrate, but the electrodes are not always necessary. When the electrodes are not provided on both ends of the board, the holding parts of the metal case only elastically contact the end surfaces of the board, respectively, and are not soldered. Therefore, when it is necessary to firmly bond the metal case and the substrate, means such as fixing the end face of the side wall of the metal case and the edge of the substrate with an adhesive is used.

The shape of the metal case and the substrate is also arbitrary, and for example, the side wall portion may be arranged inside the outer circumference of the metal case.

[0029]

As is apparent from the above description, according to the present invention, the substrate is supported by the side wall of the metal case and the substrate is held by the spring force of the pair of holding portions. Even if mechanical vibration or the like from the outside is applied to the electronic components before they are joined together, the position of the substrate does not shift with respect to the metal case, so that good assemblability can be obtained.

Further, the process of forming the notch of the substrate and the process of forming the rib of the metal case, which have been conventionally required, are unnecessary, and the number of manufacturing steps can be reduced. Since the notch is not provided in the substrate, there is no concern that the effective space of the substrate will be reduced accordingly. Furthermore, when mounting this electronic component on a printed wiring board or the like, the electronic component temporarily attached to the printed wiring board is reflowed with the metal case facing down, and at that time, the solder that bonds the metal case and the substrate, etc. Even if it is re-melted, since the holding portion holds the substrate with sufficient force, there is no risk of the metal case falling off.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of an electronic component according to the present invention.

FIG. 2 is a front view of the electronic component shown in FIG. 1 before assembling.

FIG. 3 is a front view of the electronic component shown in FIG. 2 after assembling.

FIG. 4 is an exploded perspective view showing a second embodiment of an electronic component according to the present invention.

5 is a front view of the electronic component shown in FIG. 4 before assembling.

6 is a front view of the electronic component shown in FIG. 5 after assembling.

FIG. 7 is a front view of a third embodiment of an electronic component according to the present invention before assembly.

8 is a front view of the electronic component shown in FIG. 7 after assembling.

FIG. 9 is an exploded perspective view showing a fourth embodiment of an electronic component according to the present invention.

10 is a front view of the electronic component shown in FIG. 9 before assembling.

11 is a front view of the electronic component shown in FIG. 10 after assembly.

FIG. 12 is an exploded perspective view showing a conventional electronic component.

FIG. 13 is an exploded perspective view showing another conventional electronic component.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electronic component 2 ... Metal case 4, 5, 6, 7 ... Side wall part 4a, 5a, 6a, 7a ... Upper end surface 8, 9 ... Holding part 10 ... Opening part 11 ... Substrate 14 ... Electric functional element 21 ... Electronic part 22 ... Metal case 24, 25 ... Side wall part 24a, 25a ... Upper end surface 26, 27 ... Holding part 28 ... Opening part 36 ... Electronic part 37, 38 ... Holding part 51 ... Electronic part 52 ... Metal case 54, 55, 56, 57 ... Side wall part 58, 59 ... Holding part 60 ... Opening part

Claims (1)

[Claims] 1. A substrate on which an electric functional element is mounted, an opening for accommodating the electric functional element mounted on the substrate, and a pair of holding portions elastically contacting both end surfaces of the substrate, respectively. An electronic component, comprising: a metal case having a side wall portion that supports the substrate at an end face.