JP2012090481A - Waterproof case and on-vehicle electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waterproof case for an electronic apparatus enabling a simple leakage test with easy assembling work, no increase in size and improved waterproof performance.SOLUTION: A waterproof case includes: a case body 1 having an opening 1a and a groove-shaped recess 1b2 formed at a part of a peripheral edge of the opening 1a by intersecting with the circumferential direction; an elastic body 3 to which conductors S are inserted and which is fitted in the recess 1b2; and a lid body 2 made to abut on a portion at the peripheral edge of the opening 1a excluding the recess 1b2 and on the elastic body 3 and closing the opening 1a. A groove 1c in the circumferential direction is arranged in the portion at the peripheral edge of the opening 1a excluding the recess 1b2, and a projecting part 2a fitted to the groove 1c is arranged in the lid body 2. A seal member is disposed in the groove 1c. In the elastic body 3, a projection is provided around a peripheral face coming into contact with the recess 1b2 and the lid body 2, and annular projecting parts coming into contact with the perimeter of the inserted conductors S are provided circumferentially.

Description

  The present invention relates to a waterproof case in which a lead wire is wired inside and outside the case, and an in-vehicle electronic device including the waterproof case.

  In the technical field of waterproof cases in which electronic devices and the like are housed, after applying a liquid sealant to the periphery of the opening on one side of the case body, the rubber grommet (elastic body) through which the conductive wire is inserted is opened. There is known a waterproof case having a structure that fits into a recess formed in a part of the periphery of the cover, and then affixes the cover body to the periphery of the opening to fix it with screws (for example, see Patent Document 1).

JP 2002-369346 A

  In general, in order to inspect the sealing performance of a waterproof case or the like, a method is employed in which the entire inspection object is placed in a sealed chamber and the sealing performance is tested by a change in pressure when the inside of the chamber is pressurized. However, when the size of the object to be inspected is large, a large chamber is required, which increases the cost.

  Moreover, in the waterproof case described in Patent Document 1, a liquid sealant is applied to the periphery of the opening of the case main body with which the lid abuts to ensure waterproofness. Since the peripheral edge is a flat surface, the operation of uniformly applying the liquid sealing agent is troublesome, and there is a possibility that the waterproofing may be insufficient when the application amount is not uniform. Here, in order to improve the sealing performance, it is possible to increase the width of the peripheral edge of the opening of the case body to increase the contact area with the lid, but the waterproof case is enlarged and provided with the waterproof case. There is a problem that the size of the equipment becomes large.

  The present invention has been made in view of the circumstances as described above, a waterproof case that enables a simple leak test while ensuring sealing performance, and an assembly operation that is easy and does not increase in size. It is an object of the present invention to provide a waterproof case with improved waterproof performance and to provide an in-vehicle electronic device provided with the waterproof case.

  The waterproof case according to the present invention has an opening, a case main body in which a groove-like recess intersecting the circumferential direction is formed at a part of the periphery of the opening, and a conductive wire is inserted and fitted into the recess. A waterproof case including a portion excluding the recess at the periphery of the opening and a lid that contacts the elastic body and closes the opening, and the recess at the periphery of the opening A sealing material is disposed between the portion excluding the cover and the lid.

  In the present invention, an elastic body into which a conducting wire is inserted is fitted into a groove-like recess formed so as to intersect the circumferential direction at a part of the periphery of the opening of the case body, and the opening of the opening A sealing material is disposed between a portion excluding the recess at the periphery and a lid that closes the opening, and the lid is brought into contact with the portion excluding the recess at the periphery of the opening and the elastic body.

  The waterproof case according to the present invention is provided with a groove portion along a circumferential direction in one of a portion excluding the concave portion at a peripheral edge of the opening portion or a portion excluding a contact portion of the elastic body in the lid body, and the groove portion on the other side. A protrusion to be fitted is provided, and the sealing material is disposed in the groove.

In the present invention, a seal material is disposed in a groove portion provided along the circumferential direction in a portion excluding the concave portion at a peripheral edge of the opening portion, and in a portion excluding the contact portion of the elastic body in the lid body. The provided protrusion is fitted into the groove.
Or, a seal member is disposed in a groove portion provided along the circumferential direction in a portion excluding the contact portion of the elastic body in the lid body, and a ridge portion provided in a portion excluding the concave portion in the peripheral edge of the opening portion. Is fitted into the groove of the lid.

The waterproof case according to the present invention is characterized in that the elastic body is provided with a protrusion on the circumferential surface that contacts the recess and the lid.
In the present invention, the elastic body fitted in the concave portion is in contact with the concave portion by a protrusion provided on the peripheral surface, and the elastic body in contact with the lid body is a protrusion provided on the peripheral surface. Touch the lid.

The waterproof case according to the present invention is characterized in that the elastic body has an annular protrusion that contacts the entire circumference of the inserted conductive wire.
In the present invention, the annular protrusion provided around the elastic body contacts the entire circumference of the conducting wire inserted through the elastic body.

The waterproof case according to the present invention is characterized in that the case main body and the lid are made of resin.
In the present invention, the case main body and the lid made of resin are easily deformed when subjected to external pressure.

An in-vehicle electronic device according to the present invention includes the waterproof case, and an electronic device is accommodated in the waterproof case.
In the present invention, the waterproof case containing the electronic device is installed in the vehicle body.

  According to the present invention, since the sealing material is installed between the portion excluding the concave portion where the elastic body is fitted at the periphery of the opening of the case body and the lid that closes the opening, the elastic body is not fitted. The sealing performance between the case main body and the lid body can be ensured by the sealing material at the place, and the sealing performance can be secured by the elastic body contacting the case main body and the lid body at the place where the elastic body is fitted. Furthermore, a gas ejection needle or the like is inserted from an abutting portion between the elastic body not provided with the sealing material and the lid or the case main body, the gas is filled inside the case, and the presence or absence of gas leaking to the outside is detected. A leak test can be performed by the method. As a result, a waterproof case is provided that allows a simple leak test while ensuring sealing performance.

  In addition, according to the present invention, since the sealing material is installed in the groove provided in one of the portion excluding the concave portion at the periphery of the opening of the case body or the portion excluding the contact portion of the elastic body in the lid body. The sealing material is easy to install, and the fitting portion between the groove and the protrusion that fits into the groove is not a flat surface, but the contact area becomes large. There is no need to increase the width. As a result, a waterproof case that is easy to assemble, does not increase in size, and has improved waterproof performance is provided.

  Further, according to the present invention, the electronic device is housed in a waterproof case having a small size and high sealing performance, and a highly reliable in-vehicle electronic device is provided.

It is a top view of the case main body which comprises the waterproof case which concerns on this invention. It is a side view of the case main body shown in FIG. It is sectional drawing in the III-III line of FIG. It is a top view of the lid which constitutes the waterproof case concerning the present invention. It is a side view of the cover body shown in FIG. It is sectional drawing in the VI-VI line of FIG. It is a front view of the elastic bush which comprises the waterproof case which concerns on this invention. It is a top view of the elastic bush shown in FIG. It is sectional drawing in the IX-IX line of FIG. It is a top view of the waterproof case of the state which attached the cover body. It is sectional drawing in the XI-XI line of FIG. It is a side view of the waterproof case shown in FIG. It is a figure explaining the outline | summary of a leak test.

Hereinafter, embodiments of a waterproof case according to the present invention will be described in detail with reference to the drawings.
1 is a plan view of a case body 1 constituting a waterproof case according to the present invention, FIG. 2 is a side view of the case body 1 shown in FIG. 1, and FIG. 3 is a cross-sectional view taken along line III-III in FIG.

  The case main body 1 has a substantially rectangular parallelepiped box shape, and an opening 1a is formed on one surface. The side wall 1b located at the periphery of the opening 1a has a corner portion bent at a right angle inward in plan view, and two groove-shaped recesses 1b1 and 1b2 intersecting the circumferential direction are formed at the upper end of the side wall 1b. Is formed. On the upper end surface of the side wall 1b, a groove 1c along the circumferential direction is provided in a portion excluding the recesses 1b1 and 1b2. The attachment portion 1d having through holes along the wall surface direction of the side wall 1b at nine corners between the corners of the side wall 1b and the upper surface of the same height as the upper end surface of the side wall 1b is on the outside. It is connected continuously. An attachment portion 1e having a through-hole and having a lower surface at the same height as the lower end surface of the side wall 1b is connected to a portion bent inward of the side wall 1b. A plurality of boss portions 1 f having screw holes for fixing a printed board on which an electronic device is mounted are provided on the bottom of the case body 1.

  4 is a plan view of the lid 2 constituting the waterproof case according to the present invention, FIG. 5 is a side view of the lid 2 shown in FIG. 4, and FIG. 6 is a sectional view taken along line VI-VI in FIG. FIG. 4 is a view when the lid 2 is viewed from the inner surface side.

  The lid body 2 is a plate material having an outer shape having the same dimensions as the outer shape of the side wall 1b of the case body 1 in plan view. On the peripheral edge of one surface of the lid body 2, a ridge portion 2 a is provided along the circumferential direction except for two locations 2 b 1 and 2 b 2 respectively corresponding to the two concave portions 1 b 1 and 1 b 2 of the side wall 1 b. Attaching portions 2c having through holes are provided at nine locations at the corners of the periphery of the lid body 2 and at intermediate positions between the corner portions so as to correspond to the attaching portions 1d of the case body 1.

  The material of the case body 1 and the lid body 2 is a heat-resistant synthetic resin, and the case body 1 and the lid body 2 are each formed by integral molding. Specifically, the heat-resistant synthetic resin is polybutylene terephthalate (PBT) containing 30% glass fiber (GF).

  7 is a front view of the elastic bush 3 constituting the waterproof case according to the present invention, FIG. 8 is a plan view of the elastic bush 3 shown in FIG. 7, and FIG. 9 is a cross-sectional view taken along line IX-IX in FIG.

  The elastic bush 3 has a rectangular parallelepiped disk-shaped portion 3a which is substantially the same as the inner dimensions of the recesses 1b1 and 1b2 and is thicker than the thickness of the side wall 1b. The board-shaped part 3a is formed by rounding two adjacent corners of a rectangle when viewed from the front, and forming the other two corners at right angles. Protrusions 3b for preventing detachment are provided on both end sides in the thickness direction on the peripheral surface corresponding to the other three sides other than the side connecting the two right angled portions of the plate-like portion 3a. The distance between the inner surfaces of the protrusions 3b on both sides is the same as the thickness of the side wall 1b. A protrusion 3a1 is provided around the entire range of the peripheral surface of the disk-shaped portion 3a. Although the number of the protrusions 3a1 is 2 in the figure, other numbers may be used, and it is preferable that the number is 3 or more. A plurality of insertion holes 3c through which the conducting wire is inserted are provided so as to penetrate the plate-like portion 3a. A protrusion 3c1 is provided around the inner peripheral surface of each insertion hole 3c. The number of protrusions 3c1 is three in the figure, but other numbers may be used. The elastic bush 3 is fitted into the recesses 1b1 and 1b2 of the side wall 1b. 7 to 9 show the elastic bush 3 fitted into the recess 1b2, the configuration of the elastic bush 3 fitted into the recess 1b1 is the same.

  The material of the elastic bush 3 is rubber. Specific examples include silicone rubber, ethylene propylene rubber (EPDM), fluorine rubber, styrene butadiene rubber, butadiene rubber, and nitrile butadiene rubber. The rubber hardness of the elastic bush 3 is preferably in the range of 40 degrees to 60 degrees.

  Next, assembly of the waterproof case according to the present invention will be described. 10 is a plan view of the waterproof case with the lid 2 attached, FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. 10, and FIG. 12 is a side view of the waterproof case shown in FIG.

  First, the printed circuit board P on which the electronic device is mounted is fixed to each boss 1f at the bottom of the case body 1 by screwing, and the two elastic bushes 3 through which the plurality of conductors S are inserted are connected to the concave portions of the side wall 1b. Fit to 1b1 and 1b2. The electronic device mounted on the printed circuit board P is a vehicle-mounted electronic device. The plurality of conductors S are power supply lines and signal lines from an external device, and the tips of the conductors S are fixed to the connection location of the printed circuit board P by metal fittings with screws or the like.

  Next, a sealing material is installed in the groove 1c of the side wall 1b. Specifically, a room-temperature curable adhesive, silicon rubber, or the like is uniformly applied as a sealing material in the groove 1c. In addition to these coating-type seal materials, a seal material that is pre-molded with silicon rubber or the like in accordance with the shape of the groove portion 1c may be fitted into the groove portion 1c.

  Finally, the lid body 2 with the surface provided with the protrusion 2a is placed on the side wall 1b, and the screws 9 inserted through the nine mounting portions 2c around the lid body 2 are attached to the mounting portion 1d of the side wall 1b. The lid 2 is joined to the case body 1 by screwing. Here, the waterproof case 10 is made of resin, and is easily broken at the time of an accident, so that it can be disposed in the crushable zone at the front of the vehicle. The assembled waterproof case is screwed and fixed to the housing of the vehicle by an attachment portion 1e provided at the bottom of the case body 1 and an attachment member (not shown).

  With the waterproof case 10 according to the present invention, at the periphery of the opening 1a, the protrusion 2a of the lid 2 is fitted into the groove 1c of the portion excluding the recesses 1b1 and 1b2 on the upper end surface of the side wall 1b with the sealing material in between. In addition, since the protrusion 3a1 on the peripheral surface of the elastic bush 3 pressed by the lid 2 abuts on the inner peripheral surface of the recesses 1b1 and 1b2 and the lid 2, the case main body 1, the lid 2 and the elastic bush 3 The sealing property between the two is ensured. Moreover, the conducting wire S inserted through the elastic bush 3 abuts on the protrusion 3c1 on the inner peripheral surface of the insertion hole 3c, and a sealing property is ensured.

Next, the waterproof performance test of the waterproof case 10 according to the present invention will be described. FIG. 13 is a diagram for explaining the outline of the leak test.
As a test apparatus, a hydrogen gas cylinder 4, an opening / closing valve 5 for switching between discharging and stopping of gas in the gas cylinder 4, a gas filling needle 6, and a gas supply unit including a hose 7 connecting them, a probe 8a And a hydrogen gas leak detection device 8 provided with

  In the test, the elastic bushing 3 is pressed from the contact point between the cover 2 and the elastic bushing 3 not provided with the sealing material, the gas sealing needle 6 is inserted into the waterproof case 10, and the open / close valve 5 is opened. Hydrogen gas is sealed in the waterproof case 10. Next, when the needle 6 is pulled out after closing the opening / closing valve 5, the elastic body 3 returns to its original shape due to elasticity, so that the contact portion between the lid 2 and the elastic bush 3 is sealed. In this state, since the waterproof case 10 is filled with high-pressure hydrogen gas, the tip of the probe 8 a is moved along the outer periphery of the waterproof case 10 to check for gas leakage from the waterproof case 10. If no gas leak is detected, the leak performance is acceptable. Such a leak test eliminates the need for a large chamber or the like that can accommodate a large test object as in a conventional leak test.

  In the above embodiment, the groove portion 1c is provided at the upper end portion of the side wall 1b of the case body 1, and the protrusion 2a that fits into the groove portion 1c is provided in the lid 2. On the contrary, the elastic bush 3 abuts. A groove portion may be provided on the peripheral edge of the lid body 2 excluding the portion, and a ridge portion that fits into the groove portion of the lid body 2 may be provided on the upper end portion of the side wall 1b of the case body 1.

  In the above embodiment, the waterproof case according to the present invention is applied to an in-vehicle electronic device, but can be applied to various electronic devices other than the in-vehicle electronic device.

DESCRIPTION OF SYMBOLS 1 Case main body 1a Opening part 1b1 Recessed part 1b2 Recessed part 1c Groove part 2 Lid 2a Projection part 3 Elastic bush (elastic body)
3a1 ridge 3c1 ridge 10 waterproof case

Claims (6)

A case main body having an opening and forming a groove-like recess intersecting the circumferential direction in a part of the periphery of the opening;
An elastic body through which a conducting wire is inserted and fitted into the recess;
A waterproof case comprising: a portion of the periphery of the opening excluding the recess; and a lid that contacts the elastic body and closes the opening;
A waterproof case, wherein a sealing material is disposed between a portion of the periphery of the opening except the recess and the lid.   A groove portion along the circumferential direction is provided on one of a portion excluding the concave portion at a peripheral edge of the opening portion or a portion excluding the contact portion of the elastic body in the lid body, and a ridge portion fitted to the groove portion is provided on the other side. The waterproof case according to claim 1, wherein the sealing material is disposed in the groove.   3. The waterproof case according to claim 1, wherein the elastic body has a protrusion provided on a peripheral surface that contacts the recess and the lid. 4.   The waterproof case according to any one of claims 1 to 3, wherein the elastic body is provided with an annular protrusion that contacts the entire circumference of the inserted conducting wire.   The waterproof case according to claim 1, wherein the case main body and the lid are made of resin.   An in-vehicle electronic device comprising the waterproof case according to claim 1, wherein an electronic device is accommodated in the waterproof case.

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