JP3488033B2 - Heavy component holding structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heavy component holding structure for fixedly holding heavy components mounted on a wiring board in a case in which they are accommodated.

[0002]

2. Description of the Related Art As a heavy component, for example, a transformer is provided in a case of a gas leak alarm, and FIG.
FIG. 4 is a sectional view showing the internal structure of the case. The case 1 is composed of an upper cover 3 and a lower cover 5, and a wiring board 7 and a transformer 9 mounted on the wiring board 7 are housed in the case 1.

The wiring board 7 is sandwiched between the bosses 3a, 5a provided on the upper and lower covers 3, 5 and is tightened with screws 11 for fixing the upper and lower covers 3, 5 from the lower cover 5 side. Fixed. The transformer 9 is the wiring board 7
The lower cover 5 is provided with the transformer fixing metal fitting 13 integrated with the transformer 9 in such a manner that the lead portion 9a is electrically connected to the conductive portion of the wiring board 7 by soldering while being placed on the upper portion. By fixing the rib 5b with the screw 15, the rib 5b is fixed to the case 1 side.

[0004]

However, since such a conventional heavy component holding structure is a structure in which the transformer 9 is fixed by the screws 15 via the transformer fixing fittings 13, the number of parts is large accordingly. In addition, the installation work was complicated.

On the other hand, in the example shown in FIG. 4, the transformer fixing fitting 13 and the screw 15 shown in FIG. 3 are abolished, and the transformer 9 is provided on the inner surfaces of the upper and lower covers 3 and 5 together with the wiring board 7. Transformer support 3 so that it is sandwiched
By additionally providing b and 5c, the problem in FIG. 3 is solved.

However, in the structure shown in FIG. 4, the transformer supporting portions 3b and 5c have the transformer 9 in consideration of manufacturing errors and the like.
Also, since the transformer 9 cannot be securely fixed because it does not come into close contact with the wiring board 7 and a slight gap is formed, the wiring board 7 has a boss 3 on the case 1 side.
Since the transformer 9 which is a heavy object applies a stress to the wiring board 7 in this state since it is sandwiched and fixed to the a and 5a, the wiring board 7 will be broken or damaged.

Even if an elastic material is interposed between the bosses 3b and 5c and the transformer 9 and the wiring board 7 in order to bring them into close contact with each other, when the transformer 9 applies a stress to the wiring board 7, the wiring board 7 becomes The elastic material is elastically deformed and displaced with respect to the surrounding fixed portion, which adversely affects the wiring board 7. Especially in recent gas leak alarms,
The change from methane detection to methane + CO detection type, and the weight of the transformer tends to increase accordingly.
Improvement was desired.

In view of the above, the present invention has an object to prevent adverse effects on the wiring board when the heavy parts mounted on the wiring board are attached to the case with a small number of parts and easy assembling work. .

[0009]

In order to achieve the above object, the present invention firstly provides wiring in a case formed by abutting the openings of the first cover and the second cover. A board and a heavy component mounted and fixed on the wiring board are respectively housed, and the wiring board is fixed and held by the heavy component and is free from the case, and the heavy component is the first component. First and second
Each cover is sandwiched and fixed between mutual fixing portions provided on the inner surface of each cover.

According to the structure for holding heavy parts as described above, since the heavy parts are clamped and fixed by the fixing portions of the first and second covers, they can be easily attached to the case, while the wiring board is Since the case is free of the case and is held by the heavy component, the load of the heavy component is not applied to the wiring board.

Secondly, the first and second covers are fixed to each other by fastening screws, and by this fastening, the heavy parts are clamped and fixed between the fixing portions.

According to the above construction, by fastening the screws, the first and second covers are fixed to each other, and at the same time when the screws are fastened, the heavy parts are clamped and fixed by the fixing portions.

Thirdly, each fixing portion provided on each of the first and second covers is composed of a rib protruding in a direction facing each other.

According to the above construction, the heavy component is clamped and fixed by the ribs provided on the first and second covers.

Fourthly, with the heavy parts positioned on the first cover side and the wiring board positioned on the second cover side, respectively, these are housed in the case, and the ribs on the second cover side are It penetrates through the rib relief formed on the wiring board.

According to the above structure, since the rib serving as the fixing portion penetrates the rib clearance portion of the wiring board, the wiring board is
Even a configuration in which the weight component is extended to the outside of the portion where it is fixed can be accommodated in the case.

Fifth, on the inner surface of each of the first and second covers,
Bosses for screw fastening for fixing the respective covers to each other are provided so as to project in directions opposite to each other and their tips are in contact with each other, and a boss escape portion through which the boss penetrates is provided on the wiring board.

According to the above construction, the screw fastening boss penetrates the boss relief of the wiring board, so that the wiring board is extended to the outside from the portion where the covers are fixed by screws. However, it can be stored in the case.

Sixth, between each rib tip and the heavy component,
An elastic material is interposed.

According to the above construction, the elastic material avoids the generation of the gap between the heavy component and the fixed portion.

Seventh, the wiring board is fixedly held by the heavy weight component by a conductive portion protruding from the heavy weight component and electrically connected to the wiring board.

According to the above construction, the wiring board is attached to the heavy component and housed in the case without the need for a dedicated fixture.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a structure for holding heavy parts showing an embodiment of the present invention. This holding structure is similar to that of FIGS. 3 and 4, and is a sectional view showing the internal structure of the case of the gas leak alarm. The case 17 is composed of an upper cover 19 which is a first cover and a lower cover 21 which is a second cover.
The wiring board 23 and the transformer 25, which is a heavy component mounted on the wiring board 23, are housed in the inside 7.

Bosses 19a and 21a are formed on the inner surface of each of the covers 19 and 21 so as to project in mutually opposite directions, and screws 27 are fastened from the side of the lower cover 21 in a state where they are butted against each other. Both covers 19,2
1 Mutually fixed. It is assumed that the bosses 19a and 21a are respectively provided on the left side and the right side in FIG.

On the inner surfaces of the upper cover 19 and the lower cover 21 which are located close to the bosses 19a, 21a between the bosses 19a, 21a, the upper ribs 19b as fixing portions for fixing the transformer 25 and Lower rib 21b
Are formed so as to project in the directions opposite to each other. Each of the ribs 19b and 21b is extended and formed on the left side and the right side in the drawing in the direction orthogonal to the paper surface in FIG. 1, and the fixed recesses 19c and 21c as shown in FIG. Has been done. This fixed recess 19
The upper and lower sides of the left and right sides of the transformer 25 are inserted into the c and 21c, whereby the upper and lower ribs 19b and 21b are inserted into the transformer 2.
5 is fixed and held so as to sandwich it from above and below.

In the example of FIG. 1 described above, the elastic member 29 is interposed on the surface of the upper recess 19c of the upper rib 19b facing the upper surface of the transformer 25, whereby the transformer 25 and the upper and lower ribs 19b and 21b are provided. Keeps close contact with no gap.

On the lower surface of the transformer 25, a lead portion 31 as a conductive portion is formed so as to project, and the lead portion 31 is soldered while penetrating the wiring board 23.
The wiring board 23 is electrically connected to the transformer 25, and at the same time, is fixed and held in a state in which the lower surface is closely attached to the transformer 25, and is in a free state with respect to the case 17. In addition, the wiring board 23 includes a lower rib 21 b of the lower cover 21.
And a rib clearance hole 23a as a rib clearance portion that is inserted therethrough and a boss clearance hole 23b as a boss clearance portion that is inserted through which the boss 19a of the upper cover 19 is inserted. .

According to the above-described structure for holding heavy components, the transformer 25 is only clamped and fixed between the upper rib 19b of the upper cover 19 and the lower rib 21b of the lower cover 21, so that the transformer 25 is fixed. A dedicated screw tightening work for fixing the 25 is unnecessary, the number of parts is small by that much, and the fixing work of the transformer 25 is easy. On the other hand, the wiring board 23 is fixedly held by the transformer 25 and is free from the case 17, so that the transformer 2
The load of 5 does not act on the wiring board 23, so that the wiring board 23 is prevented from being broken or damaged, and is not adversely affected by the load of the transformer 25.

Further, as the work for fixing the transformer 25,
It suffices to cover the upper cover 19 with the transformer 25 placed on the lower rib 21b of the lower cover 21, and fasten the screw 27 in this state. At this time, however, the manufacturing error of the case 17 and the manufacturing variation of the transformer 25 may occur. The upper rib 19
Although a slight gap may be formed between b and the transformer 25, since the elastic material 29 is provided in this gap,
The transformer 25 is fixedly held in a state of being in close contact with the upper rib 19b and the lower rib 21b, so that the transformer 25 is reliably held.

The wiring board 23 has rib clearance holes 23.
a and the boss escape hole 23b are formed, and the lower rib 21b and the boss 19a are inserted into the escape holes 23a and 23b, respectively.
However, each boss 19a, 2 on the outer side of each rib 19b, 21b
Even if the structure is extended to the outer side of 1a, it can be housed in the case 17, whereby the wiring board 23 can be housed.
Can be used as desired.

Depending on the shape of the wiring board 23, the rib clearance hole 2 may be used as a rib clearance portion and a boss clearance portion into which the lower rib 21b and the boss 19a are inserted, respectively.
3a and the boss escape hole 23b, instead of the wiring board 23
You may make it the notch part which notched the periphery.

[0033]

As described above, according to the first aspect of the invention, since the heavy component is configured to be sandwiched and fixed by the fixing portion when fixing the upper and lower covers to each other, the heavy component is attached to the case. It can be easily done, while the wiring board is held by the heavy parts in a state where it is free from the case, so the load of the heavy parts is not applied to the wiring board and damage such as cracking of the wiring board can be prevented. it can.

According to the second invention, the heavy parts can be fixed at the same time by fastening the screws for fixing the first and second covers to each other, so that the work of attaching the heavy parts to the case is further simplified. can do.

According to the third invention, the heavy parts are the first and second parts.
It is clamped and fixed by the ribs provided on each second cover,
As a result, the same effect as that of the first invention can be obtained.

According to the fourth aspect of the invention, since the rib serving as the fixing portion penetrates the rib clearance portion of the wiring board, the wiring board is extended to the outside of the portion for fixing the heavy component. Even the one having the above configuration can be accommodated in the case, and a desired wiring board can be used.

According to the fifth aspect of the present invention, the screw fastening boss penetrates the boss relief of the wiring board, so that the wiring board extends from the portion where the covers are fixed by screws to the outside. Even the extended structure can be accommodated in the case, and a desired wiring board can be used.

According to the sixth aspect of the invention, since the elastic member is refurbished between the heavy component and the fixing portion, it is possible to avoid the occurrence of a gap between them and to fix the heavy component more reliably. it can.

According to the seventh aspect of the invention, the wiring board is configured to be fixedly held by the heavy weight component by the conductive portion projecting from the heavy weight component, so that the wiring board does not require a dedicated fixture. Since it is attached to a heavy component and housed in a case, a dedicated fixture is not required, and the number of components can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a weight component holding structure according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a fixing recess for fixing and holding a transformer in the holding structure of FIG.

FIG. 3 is a cross-sectional view of a conventional heavy component holding structure.

FIG. 4 is a cross-sectional view of a heavy component holding structure showing another conventional example.

[Explanation of symbols]

17 cases 19 Top cover (first cover) 19b Upper rib (fixed part) 21 Lower cover (second cover) 21b Lower rib (fixed part) 23 wiring board 23a Rib relief hole (rib relief portion) 23b Boss clearance hole (boss clearance) 25 transformers (weight parts) 27 screws 29 Elastic material 31 Lead part (conductive part)

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-3-167892 (JP, A) Actual development Sho 49-125225 (JP, U) Actual development Sho 61-140577 (JP, U) Actual development 3- 85690 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01F 27/06

Claims (7)

(57) [Claims] 1. A case formed by abutting the openings of the first cover and the second cover, respectively,
A wiring board and a heavy component mounted and fixed on the wiring board are respectively housed, and the wiring board is fixedly held by the heavy component and is free from the case, and the heavy component is A holding structure for heavy parts, characterized in that it is sandwiched and fixed between mutual fixing portions provided on the inner surfaces of the first and second covers. 2. The first and second covers are fixed to each other by fastening screws, and the heavy component is clamped and fixed between the fixing portions by the fastening. Item 3. The heavy component holding structure according to Item 1. 3. The heavy component according to claim 1, wherein each of the fixing portions provided on each of the first and second covers is composed of a rib protruding in a direction facing each other. Holding structure. 4. With the heavy component positioned on the side of the first cover and the wiring board positioned on the side of the second cover, respectively, these are housed in a case, and the ribs on the side of the second cover are wiring. 4. The heavy component holding structure according to claim 3, wherein the rib escape portion formed on the substrate penetrates. 5. A boss for fastening a screw for fixing the respective covers to each other is provided on the inner surface of each of the first and second covers in a state in which the bosses project in mutually opposing directions and their tips are in contact with each other. The holding structure for heavy parts according to claim 4, characterized in that the wiring board is provided with a boss relief portion through which the boss penetrates. 6. The heavy component holding structure according to claim 3, wherein an elastic material is interposed between each rib tip and the heavy component. 7. The heavy component holding structure according to claim 1, wherein the wiring substrate is fixedly held by the heavy component by a conductive portion protruding from the heavy component and electrically connected to the wiring substrate.