CN114173498B - Resin structure - Google Patents

Abstract

The invention provides a resin structure, which has good balance between waterproof performance and storage capacity. The resin structure (1) is provided with: a box-shaped first resin body (10) having an opening, and a second resin body (20) assembled with the first resin body (10) so as to cover the opening. The first resin body (10) has: a through part (13) penetrating through the peripheral wall (11) of the first resin body (10) in the thickness direction, and first engaging parts (14, 18) arranged to cover the through part (13). The second resin body (20) has: a water blocking wall (24) protruding from the peripheral wall (21) of the second resin body (20) in the direction of assembly of the first resin body (10) in proximity to the first resin body (10) and having a shape corresponding to the through portion (13), and second engagement portions (25, 27) corresponding to the first engagement portions (14, 18). When the first and second resin bodies (10, 20) are assembled, the first engagement portion (18) and the second engagement portion (27) are engaged with each other in a state in which the water blocking wall (24) and the second engagement portion (25) are disposed with the through portion (13) interposed therebetween in the thickness direction.

Description

Resin structure

Technical Field

The present invention relates to a resin structure.

Background

Conventionally, there has been proposed a resin structure in which a plurality of resin bodies are assembled to each other, such as an electric junction box (e.g., a relay box) mounted on a vehicle. For example, one existing electrical junction box has: a main body housing for holding electronic components and the like, and a lower cover assembled at the lower part of the main body housing. In this conventional electrical junction box, a locking piece extending from a lower cover to a main body case is inserted into and locked in a locking hole of the main body portion, whereby the lower cover is fixed to the main body case (see, for example, patent documents 1 and 2).

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2019-213293

Patent document 2: japanese patent application laid-open No. 2019-213394

Disclosure of Invention

Technical problem to be solved by the invention

However, when a plurality of resin bodies are assembled together, a slight gap (e.g., a gap between surfaces at a position where the surfaces of the resin bodies are aligned with each other) may be present at the boundary between the resin bodies due to molding accuracy of the resin bodies, temperature of the use environment, and the like, as in the case of the conventional lower cover and main body case of the resin structure. When the engagement position between the lock piece and the lock hole is present in the vicinity of the boundary, water entering the engagement position may enter the resin structure through the gap of the boundary when the engagement position between the lock piece and the lock hole is flooded.

In order to improve the waterproof performance of the resin structure, it is conceivable to multiply the peripheral wall of the resin structure (so-called double-wall structure). However, in this case, the amount by which the peripheral wall thickness of the resin body increases may decrease the internal space of the resin structure accordingly, and the original storage capacity of the resin structure may be impaired. Conversely, if the peripheral wall is multilayered while maintaining the area of the internal space of the resin structure, the outer shape of the resin structure is increased, which is not preferable from the viewpoint of downsizing the device.

Thus, it is generally difficult to achieve both improvement in the waterproof performance and improvement in the storage capacity of the resin structure.

The present invention provides a resin structure having a good balance between waterproof performance and storage capacity.

Technical scheme for solving technical problems

In order to achieve the above object, the resin structure of the present invention is characterized by the following [1] to [2].

[1]

A resin structure is provided with: a box-shaped first resin body having an opening, and a second resin body assembled with the first resin body so as to cover the opening,

The first resin body has: a through portion penetrating through a peripheral wall of the first resin body in a thickness direction, and a first engaging portion provided so as to cover the through portion,

The second resin body has: a water blocking wall protruding from a peripheral wall of the second resin body in the assembling direction of the first resin body so as to be close to the first resin body and having a shape corresponding to the through portion, and a second engaging portion corresponding to the first engaging portion,

When the first resin body is assembled with the second resin body,

The first engaging portion is engaged with the second engaging portion in a state where the water blocking wall and the second engaging portion are disposed with the through portion interposed therebetween in the thickness direction.

[2]

Based on the resin structure described in the above [1],

The second resin body has a protrusion protruding from the water blocking wall so as to enter the through portion,

When the first resin body is assembled with the second resin body,

The peripheral wall of the first resin body is configured to be aligned with the protrusion, and a gap is defined between the protruding end of the protrusion and the second engagement portion.

The resin structure according to the above [1], wherein the first engaging portion of the first resin body is engaged with the second engaging portion of the second resin body in a state in which the water blocking wall of the second resin body is disposed with the through portion of the peripheral wall of the first resin body interposed therebetween in the thickness direction when the first resin body and the second resin body are assembled. Thus, since at least one of the first engaging portion and the second engaging portion is deformable to enter the through portion when the first engaging portion and the second engaging portion are engaged, the amount of deformation (for example, the amount of deflection in the case of the engaging portion having the lock arm shape) at the time of engagement of the engaging portion can be increased as compared with the case of the engaging portion having no through portion. This enables the first engagement portion and the second engagement portion to be firmly engaged. In addition, in a case where the engagement state of the first engagement portion and the second engagement portion is visually checked, a portion where the deformation amount (for example, the deflection amount) is large can be easily checked. Further, since the through portion is covered with the water blocking wall of the first engaging portion and the second resin body, even if the through portion is provided in the peripheral wall of the first resin body, the water blocking property of the resin structure can be ensured. Therefore, the resin structure of the present structure improves the original function of assembling a plurality of resin bodies, and has a better balance between the waterproof performance and the storage capacity than when the peripheral walls of the first resin body and the second resin body are multilayered.

The "through portion" may be, for example, a slit or a slit extending from an edge portion of the peripheral wall of the first resin body in the assembly direction, or may be a window-like through hole provided in the peripheral wall of the first resin body, or may have another form.

The resin structure according to the above [2], wherein the projection protruding from the water blocking wall is engaged with the peripheral wall of the first resin body, and a gap is defined between the projection and the second engaging portion. This can prevent water from entering the engagement position due to the protrusion abutting the peripheral wall of the first resin body, and can drain water through the gap even when the engagement position is flooded. This can quickly remove water from the engagement position, and prevent water from remaining in the engagement position. Therefore, the resin structure of the present structure can further improve the waterproof performance.

ADVANTAGEOUS EFFECTS OF INVENTION

As described above, according to the present invention, a resin structure having a good balance between waterproof performance and storage capacity can be provided.

The present invention is briefly described above. Further, the details of the present invention will be further clarified by reading the modes for carrying out the invention described below with reference to the drawings.

Drawings

Fig. 1 is a perspective view of a resin structure according to an embodiment of the present invention.

Fig. 2 is a perspective view showing a state in which the first locking portion of the main body case is separated from the second locking portion of the lower cover, fig. 2 (a) shows a state seen from the outside, and fig. 2 (b) shows a state seen from the inside.

Fig. 3 (a) is a cross-sectional view of fig. 2 (a), and fig. 3 (b) is a view corresponding to fig. 3 (a) in a state where the first locking portion is engaged with the second locking portion.

Fig. 4 is a view of the cross section shown in fig. 3 (b) from the front.

Detailed Description

Embodiment

Next, a resin structure 1 according to an embodiment of the present invention shown in fig. 1 will be described with reference to the drawings. The resin structure 1 is typically a relay box (electric junction box) mounted on a vehicle or housing electronic components such as a relay.

As shown in fig. 1 and 2, the resin structure 1 includes a main body case 10 configured to house electronic components (other components, not shown) such as a relay, and a lower cover 20 assembled to a lower end portion of the main body case 20 so as to close a lower end opening of the main body case 20. The main body case 10 and the lower cover 20 are each a resin molded body. The main body case 10 corresponds to the "first resin body" of the present invention, and the lower cover 20 corresponds to the "second resin body" of the present invention.

Hereinafter, for convenience of explanation, as shown in fig. 1 to 4, "up-down direction", "circumferential direction", "inside-outside direction", "up", "down", "inside" and "outside" are defined. The "up-down direction", "circumferential direction" and "inside-outside direction" are orthogonal to each other. When the resin structure 1 is mounted on a vehicle, the "up-down direction" corresponds to the up-down direction of the vehicle. The "circumferential direction" corresponds to the circumferential direction of the peripheral wall 11 described later and the peripheral wall 21 described later of the main body case 10, and the "inward and outward direction" corresponds to the thickness direction of the peripheral wall 11 and the peripheral wall 21. Next, the respective members constituting the resin structure 1 will be described in order.

First, the main body case 10 will be described. As shown in fig. 1, the main body case 10 has a substantially rectangular tubular peripheral wall 11 extending in the up-down direction. First locking portions 12 are provided at a plurality of positions in the circumferential direction on the outer surface of the substantially rectangular frame-shaped lower end edge portion of the peripheral wall 11. In a state where the assembly of the main body case 10 and the lower cover 20 is completed (see fig. 1), the plurality of first locking portions 12 are engaged with a plurality of second locking portions 22 (also see fig. 3 b) provided in the lower cover 20, which will be described later, respectively.

Specifically, as shown in fig. 2a and 2b, each first locking portion 12 is constituted by a substantially rectangular notch portion 13 recessed upward from the lower end edge of the peripheral wall 11 (see fig. 2 b), an outer wall portion 14 which is separated from the notch portion 13 and the peripheral edge portion of the notch portion 13 by a predetermined distance outward and covers the notch portion 13 and the peripheral edge portion of the notch portion 13, and a pair of side wall portions 15 which extend along the peripheral end edges of the outer wall portion 14 and connect the peripheral end edges of the outer wall portion 14 and the peripheral wall 11 in the inner-outer direction.

The cutout portion 13 penetrates the peripheral wall 11 in the inner-outer direction. In this example, the outer wall 14 includes a substantially rectangular flat plate-shaped first portion 14a that covers the cutout 13 and the peripheral edge of the cutout 13, and a substantially rectangular flat plate-shaped second portion 14b that is continuous with the upper side of the first portion 14a and smaller than the first portion 14 a. A through hole 16 (see fig. 2 a and 3 a) penetrating in the vertical direction is defined by the second portion 14b of the outer wall portion 14, the peripheral wall 11, and the pair of side wall portions 15, and an upper end opening 16a of the through hole 16 communicates with the cutout portion 13.

A pair of groove portions 17 are defined by a pair of side edge portions 13b (see fig. 2 b), a pair of side wall portions 15, and (a first portion 14a of) the outer wall portion 14, which extend in the up-down direction, of the peripheral edge portions of the cutout portion 13. The pair of groove portions 17 are recessed outward in the circumferential direction, open inward in the circumferential direction, and extend in the up-down direction. In a state where the assembly of the main body case 10 and the lower cover 20 is completed (see fig. 1), a pair of flange portions 28 (see fig. 2 a), which will be described later, of the lower cover 20 are fitted into the pair of groove portions 17.

A locking projection 18 that projects inward and extends in the circumferential direction is provided on the inner side surface of the circumferential center portion of the lower end portion of (the first portion 14a of) the outer wall portion 14 ((b) of fig. 2). In a state where the assembly of the main body case 10 and the lower cover 20 is completed (see fig. 1), the locking projection 18 is engaged with a locking projection 27 (see also fig. 3 (b)) described later of the lower cover 20.

A recess 19 recessed inward and extending in the circumferential direction is formed on the outer side surface of the upper edge portion extending in the circumferential direction in the peripheral edge portion of the cutout portion 13 (see fig. 3 (a)), and as a result, a stepped surface 19a extending in the circumferential direction and facing downward is formed (see fig. 3 (a)).

Next, the lower cover 20 will be described. As shown in fig. 1, the lower cover 20 integrally includes a substantially rectangular tubular peripheral wall 21 extending in the vertical direction, and a bottom wall portion (not shown) closing the lower end opening of the peripheral wall 21. The outer surface of the upper edge of the peripheral wall 21, which is substantially rectangular frame-shaped, is provided with second locking portions 22 at a plurality of positions in the circumferential direction, corresponding to the plurality of first locking portions 12 of the main body case 10. An annular ridge 23 (see fig. 1 and 2 (a)) extending in the circumferential direction except for the circumferential positions corresponding to the plurality of second locking portions 22 is formed on the outer surface of the upper end edge portion of the peripheral wall 21.

As shown in fig. 2 a and 2b, each second locking portion 22 is constituted by a substantially rectangular flat water blocking wall 24 (splash preventing wall) protruding upward from the upper end edge of the peripheral wall 21, a substantially rectangular flat outer wall 25 located at a position separated from the water blocking wall 24 outward by a predetermined distance so as to face the water blocking wall 24 in the inner-outer direction, and a pair of side wall portions 26 extending in the up-down direction along the circumferential both end edges of the outer wall 25 and connecting the circumferential both end edges of the outer wall 25 with the peripheral wall 21 and the water blocking wall 24 in the inner-outer direction.

The water blocking wall 24 has a substantially rectangular shape corresponding to the shape of the cutout portion 13 of the main body case 10. Only the upper regions of the peripheral edges of the outer wall portion 25 are connected to the pair of side wall portions 26, and the lower regions of the outer wall portion 25 constitute substantially rectangular flat plate-shaped lock arms 25b extending downward in a cantilever shape. The lock arm 25b is elastically deformable over a predetermined range in the inward-outward direction. An outer surface of the lock arm 25b is provided with a lock projection 27 protruding outward and extending in the circumferential direction (see fig. 2 (a)) corresponding to the lock projection 18 of the main body case 10.

A pair of flange portions 28 extending outward in the circumferential direction and extending in the up-down direction from the outer end portions of the above-described members are formed in the pair of side wall portions 26 in correspondence with the pair of groove portions 17 of the main body case 10 (see fig. 2 (a)). The lower end of each flange 28 is connected to the annular ridge 23 located in the vicinity thereof. As shown in fig. 3a and 3b, a protruding portion 29 protruding outward and extending in the circumferential direction is formed on the outer side surface (surface facing the outer wall portion 25) of the upper end edge portion of the water blocking wall 24. A gap S (see fig. 4) is defined between the protruding end surface (outer end surface) of the protruding strip portion 29 and the outer wall portion 25. The above description has been made of the respective members constituting the resin structure 1.

Next, assembly of the main body case 10 and the lower cover 20 will be described. In order to assemble the main body case 10 and the lower cover 20, first, as shown in fig. 2 (a) and 3 (a), the main body case 10 and the lower cover 20 are arranged with the main body case 10 positioned above the lower cover 20.

Next, the main body case 10 and the lower cover 20 are brought into vertical proximity, and the lower end edge portion of the peripheral wall 11 of the main body case 10 and the upper end edge portion of the peripheral wall 21 of the lower cover 20 are fitted. The fitting is performed such that the lower end edge portion of the peripheral wall 11 of the main body case 10 is positioned outside the upper end edge portion of the peripheral wall 21 of the lower cover 20, the pair of flange portions 28 of each second locking portion 22 are inserted into the pair of groove portions 17 of the corresponding first locking portion 12, the upper end edge 13a (see fig. 2 (b) and the like) of the cutout portion 13 of each first locking portion 12 extending in the circumferential direction is sandwiched by the upper end edge portion of the water blocking wall 24 of the corresponding second locking portion 22 and the upper end edge portion of the outer wall portion 25 in the inner-outer direction, and the projecting strip portion 29 of each second locking portion 22 is inserted into the cutout portion 13 of the corresponding first locking portion 12 (see fig. 3 (b) and 4).

This fitting is continued until the lower end edge of the peripheral wall 11 and the annular ridge portion 23 of the peripheral wall 21, the upper end edge 13a of each cutout portion 13 and the upper end surface of the corresponding ridge portion 29, and the upper end edge 25a of each outer wall portion 25 extending in the circumferential direction and the corresponding step surface 19a are aligned in the up-down direction.

Before the lower end edge of the peripheral wall 11 and the annular ridge 23 or the like of the peripheral wall 21 are engaged with each other, the locking arms 25b are temporarily elastically deformed inward by the pressing from the locking projections 18 in the respective second locking portions 22, and the locking projections 18 and 27 pass over the top of each other. At this time, the lock arm 25b is deformable to enter the notch portion 13. Therefore, the amount of inward deformation of the lock arm 25b when engaged can be increased as compared with the case where the notch portion 13 is not provided.

When the lower end edge of the peripheral wall 11 and the annular projection 23 or the like of the peripheral wall 21 are opposed to each other as shown in fig. 3 (b) and 4, the locking projection 27 and the locking projection 18 are engaged with each other as the locking projection 27 abuts on the upper side of the locking projection 18, and the assembly of the main body casing 10 and the lower cover 20 is completed. As a result, the resin structure 1 shown in fig. 1 can be obtained.

In a state where the assembly of the main body case 10 and the lower cover 20 is completed (see fig. 1), the plurality of locking projections 27 and the plurality of locking projections 18 are engaged with each other, whereby the main body case 10 and the lower cover 20 can be prevented from being separated in the up-down direction. Further, since the notch portion 13 is formed in the first locking portion 12, the engaged state of the lock arm 25b can be easily confirmed from below by visual inspection as compared with the case where the notch portion 13 is not provided.

In the assembled state of the main body case 10 and the lower cover 20 (see fig. 1), as shown in fig. 3 (b) and 4, the water blocking wall 24 and the outer wall 25 of the lower cover 20 are disposed with the cutout portion 13 of the peripheral wall 11 of the main body case 10 interposed therebetween in the inner-outer direction, and the cutout portion 13 is covered by (the first portion 14a of) the outer wall 14 of the main body case 10 and the water blocking wall 24 of the lower cover 20. Therefore, even if the cutout portion 13 is provided in the peripheral wall 11 of the main body case 10, it is difficult to break the water blocking property of the resin structure 1.

In a state where the assembly of the main body case 10 and the lower cover 20 is completed (see fig. 1), a so-called labyrinth structure is formed by the contact of the protruding strip portion 29 with the upper end edge 13a of the cutout portion 13 and the contact of the upper end edge 25a of the outer wall portion 25 with the step surface 19a (see fig. 4). Therefore, even if the engagement positions of the first locking portion 12 and the second locking portion 22 are flooded, water can be prevented from entering the resin structure 1 from the upper end opening 16a of the first locking portion 12 to the periphery of the labyrinth structure through the through hole 16. In addition, even if water enters the interior of the labyrinth structure, water can be discharged downward through the gap S (see fig. 4), so that water can be suppressed from stagnating in the periphery of the labyrinth structure.

< Action/Effect >

As described above, according to the resin structure 1 of the present embodiment, when the main body case 10 and the lower cover 20 are assembled, the locking projection 18 of the outer wall 14 of the main body case 10 is engaged with the locking projection 27 of the outer wall 25 of the lower cover 20 in a state where the water blocking wall 24 and the outer wall 25 of the lower cover 20 are arranged with the cut-out portion 13 of the peripheral wall 11 of the main body case 10 interposed therebetween in the thickness direction. Thus, when the locking projection 18 of the outer wall portion 14 is engaged with the locking projection 27 of the outer wall portion 25, the outer wall portion 25 (locking arm 25 b) can be deformed to enter the notch portion 13, so that the deformation amount of the outer wall portion 25 (locking arm 25 b) can be increased as compared with the case where the notch portion 13 is not provided. This can firmly engage the locking projection 18 of the outer wall 14 with the locking projection 27 of the outer wall 25. In addition, in a case where the engagement state of the engagement protrusion 18 of the outer wall portion 14 and the engagement protrusion 27 of the outer wall portion 25 is visually confirmed, or the like, it can be easily confirmed. Further, since the cutout portion 13 is covered by (the first portion 14a of) the outer wall portion 14 and the water blocking wall 24 of the lower cover 20, even if the cutout portion 13 is provided in the peripheral wall 11 of the main body case 10, it is difficult to break the water blocking property of the resin structure 1. Therefore, the resin structure 1 of the present embodiment improves the original function of assembling the main body case 10 and the lower cover 20 to each other, and has a better balance between the waterproof performance and the storage capacity than the case of forming the peripheral walls 11, 21 of the main body case 10 and the lower cover 20 into multiple layers.

Further, according to the resin structure 1 of the present embodiment, the ridge portion 29 protruding from the water blocking wall 24 is brought into abutment with the upper end edge 13a of the cutout portion 13 of the main body case 10, and a gap S (see fig. 4) is defined between the ridge portion 29 and the outer wall portion 25. This can prevent water from entering the engagement position between the first locking portion 12 and the second locking portion 22 due to contact between the protruding portion 29 and the upper end edge 13a of the notch portion 13, and can drain water through the gap S even when the engagement position is flooded. This can quickly remove water from the engagement position, and prevent water from remaining in the engagement position. Therefore, the resin structure 1 of the present embodiment can further improve the waterproof performance.

< Other modes >

The present invention is not limited to the above embodiments, and various modifications may be employed within the scope of the present invention. For example, the present invention is not limited to the above embodiment, and can be modified, improved, and the like as appropriate. In addition, the material, shape, size, number, and arrangement position of the main components of each of the above embodiments are not limited as long as the present invention can be developed.

In the above embodiment, the protruding portion 29, which is engaged with the upper end edge 13a of the cutout portion 13 of the main body case 10 in the state where the assembly of the main body case 10 and the lower cover 20 is completed, is provided in the water blocking wall 24. In contrast, the water blocking wall 24 may not be provided in the ridge portion.

In the above embodiment, in the assembled state of the main body case 10 and the lower cover 20, the step surface 19a (the concave portion 19) which is engaged with the upper end edge 25a of the outer wall portion 25 of the lower cover 20 is provided on the peripheral wall 11 (the peripheral edge portion of the cutout portion 13). In contrast, the step surface (concave portion) may not be provided on the peripheral wall 11 (peripheral edge portion of the cutout portion 13).

Here, the features of the embodiment of the resin structure 1 of the present invention are briefly summarized and listed as follows [1] to [2].

[1]

A resin structure (1) is provided with: a box-shaped first resin body (10) having an opening, and a second resin body (20) assembled with the first resin body (10) so as to cover the opening,

The first resin body (10) has: a through portion (13) penetrating through the peripheral wall (11) of the first resin body (10) in the thickness direction, and first engaging portions (14, 18) provided so as to cover the through portion (13),

The second resin body (20) has: a water blocking wall (24) protruding from the peripheral wall (21) of the second resin body (20) in the direction of assembly of the first resin body (10) so as to be close to the first resin body (10) and having a shape corresponding to the through portion (13), and second engaging portions (25, 27) corresponding to the first engaging portions (14, 18),

When the first resin body (10) and the second resin body (20) are assembled,

The first engagement portion (18) and the second engagement portion (27) are engaged with each other in a state in which the water blocking wall (24) and the second engagement portion (25) are disposed with the through portion (13) interposed therebetween in the thickness direction.

[2]

Based on the resin structure (1) described in the above [1],

The second resin body (20) has a protrusion (29) protruding from the water blocking wall (24) so as to enter the through portion (13),

When the first resin body (10) and the second resin body (20) are assembled,

The peripheral walls (11, 13 a) of the first resin body (10) are brought into close contact with the projection (29), and a gap (S) is defined between the protruding end of the projection (29) and the second engagement portion (25).

Claims (2)

1. A resin structure is provided with: a box-shaped first resin body having an opening, and a second resin body assembled with the first resin body so as to cover the opening, the resin structure being characterized in that,

The first resin body has:

a through portion penetrating through a peripheral wall of the first resin body in a thickness direction, and a first engaging portion provided so as to cover the through portion,

The second resin body has:

A water blocking wall protruding from a peripheral wall of the second resin body in the assembling direction with the first resin body in a manner close to the first resin body and having a shape corresponding to the through portion, and a second engaging portion corresponding to the first engaging portion,

When the first resin body is assembled with the second resin body,

The first engaging portion and the second engaging portion are engaged with each other in a state where the water blocking wall and the second engaging portion are disposed with the through portion interposed therebetween in the thickness direction.

2. The resin structure according to claim 1, wherein,

The second resin body has a protrusion protruding from the water blocking wall so as to enter the through portion,

When the first resin body is assembled with the second resin body,

The peripheral wall of the first resin body is brought into contact with the protrusion, and a gap is defined between the protruding end of the protrusion and the second engagement portion.