JPH0611557Y2 - Case for electric circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a case for an electric circuit in which water that has entered the case can be discharged very easily.

[Conventional technology]

For example, in a working vehicle such as a combine, an electric circuit is provided in a case for various controls such as cutting height control and handling depth control. Then, as the electric circuit heats up, dew condensation may occur in the case, and water may enter the case during work. I was trying to pull out.

[Problems to be solved by the invention]

However, if a water drain hole is simply provided on the bottom of the case, water on the work surface may bounce back and water may enter the inside of the case through the water drain hole. There were some drawbacks when it came to decrease.

An object of the present invention is to provide a case for an electric circuit in which water easily escapes from the case, bounce water or the like hardly enters the case, and the strength of the peripheral edge of the water drain hole of the case is not reduced.

[Means for solving problems]

According to the characteristic configuration of the present invention, a flange extending over the entire circumference is provided outwardly at the lower end of the peripheral wall of a downward box-shaped case body opened downward, and a bottom cover plate is provided on the lower surface of the flange via a packing. And a punching rib that bulges outward over the circumferential wall of the case body and the flange at an appropriate portion in the circumferential direction of the case body, and the punching rib is formed from the packing pinching portion at the flange portion. It is also formed to extend outward, and there is a water drainage gap inside the case rib that connects the inside and outside of the case.
Its action and effect are as follows.

[Action]

Since the ejection ribs are located on the upper surface of the drainage gap through which the water passes, the drainage gap does not directly open from the outside into the case, so the water that tries to enter the case through the drainage gap is It hits the bottom surface of the ejection rib and flows downward. Further, since the embossing rib is formed from the lower end of the peripheral wall of the case body to the flange, the strength of the flange and thus the strength of the case body can be increased by the rib effect.

〔effect〕

Condensation that occurs on the inner surface of the case due to heat generated by the electronic circuits placed in the case, rainwater, or water that enters from the work surface can flow out of the case through the drainage gap as well as from the outside. Water can be prevented from entering the case, and the reliability of the electronic circuit can be improved. In addition, the strength of the case can be increased by the rib effect of the embossing ribs, so that in a work vehicle with large vibration such as a combine, the circuit board attached to it may be damaged due to the case being distorted. Can be prevented.

〔Example〕

FIG. 1 is a plan view of an electric circuit case according to the present invention.
The respective sides are shown in FIG.

This case body (2) is a box-shaped sheet metal molded product with an open bottom, and a flange is attached to the lower end of the peripheral wall (3) of the case body (2).
(4) is provided so as to project outwardly over the entire circumference. At appropriate portions on the corners and sides of the case body (2), the punch-out ribs (5) protruding outward across the case body peripheral wall (3) and the flange (4) are formed by the punching process. Are integrated into one. At the corners of the case body (2), as shown in FIG. 1, a driving rib (5) having a substantially square shape in plan view is provided so as to project outward along two adjacent sides, and In the side portion, a projecting rib (5) having a triangular shape in plan view is provided so as to project outward. In addition, a hanging piece (9) is hung from the tip of the flange (4) over the entire circumference, and a mounting hole (on the outside of the embossing rib (5) is provided at a corner portion of the flange (4). 20) is provided.

Inside the case body (2) formed in this way, the printed circuit board (1) is arranged and the screw (11) is attached to the support portion (10) fixed to the inner surface of the ceiling wall of the case body (2). The power connection coupler (13) mounted on the upper surface of the printed circuit board (1) is fixed inside the case main body peripheral wall (3) inside the inlet (12) as shown in FIG. And the outer end of the coupler (13) is press-fitted inside the rubber seal material (14) which is arranged on the periphery of the opening of the inlet (12). That is, the sealing material (14) is the insertion part (15)
It is formed of an annular member having a substantially L-shaped cross section having a flange and a flange portion (16), and the insertion portion (15) of the sealing material (14) is inserted into the introduction port (12) from the inside of the case body (2) and the flange is formed. Part (16) to case body
Attach the sealing material (14) to the inlet (12) by contacting the inner surface of (2), and attach the end of the printed circuit board (1) to the collar (16).
While making elastic contact with the inner surface of the sealant (14), the end of the coupler (13) whose outer shape is formed to be slightly larger than the opening dimension of the sealant (14) is press-fitted into the opening of the sealant (14). Body
The periphery of the inlet (12) of (2) and the periphery of the coupler (13) are sealed with a sealing material (14). Therefore, the coupler (13) can be attached simply by inserting it into the opening of the seal material (14), and the cost can be reduced because the sealing effect is achieved by one component. Moreover, the vibration of the substrate (1) can be absorbed by the sealing material (14).

On the other hand, the bottom cover plate (6) has a shape substantially the same as that of the case body (2) and is formed in such a size as to fit inside the hanging piece (9) provided on the case body (2). ), A vertical piece (19) is hung from the periphery of the bottom bracket plate (6), and vertical pieces (19) are provided on both sides of the bottom cover plate (6).
A mounting piece (18) provided with a mounting hole (17) extends outwardly.

When connecting the bottom cover plate (6) and the case body (2), as shown in FIGS. 3 and 4, the packing (7) having elasticity around the bottom cover plate (6) is used. ) Is placed and the case body (2) is covered, and the bottom cover plate (6) and the case body (2) are connected by fixing means such as screws, welding, and rivets, and the packing (7) is the bottom. It is compressed between the cover plate (6) and the flange (4) of the case body (2) to improve the watertightness between them, and the vibration applied to the bottom cover plate (6) causes the case body (2) and thus the print. It reduces the transmission to the circuit board (1).
Further, the outer end portion of the embossing rib (5) is located outside the sandwiched portion of the packing (7) at the flange (4) portion. A water drainage gap (8) communicating with each other is formed, and water such as dew condensation water generated in the case is discharged to the outside through the water drainage gap (8). Particularly, in the corner portion of the case, the punching-out process of the punching rib (5) is largely formed, so that the water accumulated along the inner edge of the case body (2) can be effectively discharged. Also, the mounting piece (18)
As shown in FIG. 4, the lower end positions of the vertical pieces (19) provided on both sides of the case body (2) on the side where the
It is set slightly above the lower end of the hanging piece (9) of (2), and the vertical piece (19) of the bottom cover plate (6) does not contact the mounting member (not shown) of the vehicle body. , Prevents water from entering the inside of the case from the surface of the mounting member.

[Another embodiment]

The shape, size, etc. of the embossing rib (5) are not limited, and may be formed, for example, in a semicircular cross section, a U-shaped cross section or the like. The electric circuit case is not limited to the combine harvester, and can be installed not only in working vehicles such as rice transplanters and tractors but also in general passenger vehicles.

[Brief description of drawings]

The drawings show an embodiment of an electric circuit case according to the present invention,
1 is a plan view of the electric circuit case, FIG. 2 is a partially cutaway front view of the electric circuit case, and FIG. 3 is III-III of FIG.
FIG. 4 is a sectional view taken along line IV-IV of FIG. 1, and FIG. 5 is a sectional view of an essential part. (1) …… electric circuit board, (2) …… case body, (3) …… circumferential wall, (4) …… flange, (5) …… embossing rib, (6) …… bottom cover plate, ( 7) …… Packing, (8) …… Drainage gap.

Claims (1)

[Scope of utility model registration request] 1. A downward box-shaped case body opened downward.
At the lower end of the peripheral wall (3) of (2), a flange (4) is provided so as to extend all around, and a packing (7) is provided on the lower surface of this flange (4).
The bottom cover plate (6) is connected via the, and the punching that bulges outward over the peripheral wall (3) of the case body and the flange (4) at an appropriate portion in the circumferential direction of the case body (2). A rib (5) is provided, and the embossing rib (5) is formed at the flange (4) portion beyond the packing pinching portion to the outside.
A case for an electric circuit in which a drainage gap (8) for communicating the inside and the outside of the case is formed inside the embossing rib (5).