Snap-fit ​​structure and housing

Abstract

To provide a technology that pertains to a snap-fit structure with which it is possible to suppress damage to a cantilever and suppress the cantilever from coming out of place.SOLUTION: A cover 5 includes a flexible cantilever 17 that extends from a fixed-end side to a free-end side and includes an opening 21 in the cantilever 17 that is used for connection with as case 3. The case 3 includes a protrusion 19 that engages with the opening 21 and restricts the movement of the cantilever 17 and a pair of guides 29 for guiding the cantilever 17. The pair of guides 29 are constructed so as to cover both lateral sides 23 on the free-end side of the cantilever 17 in a direction perpendicular to the direction in which the cantilever 17 extends and the direction in which it is deflected. When the free-end side of the cantilever 17, while being engaged with the opening 21, is defined as the lower side and the fixed-end side defined as the upper side, the upper ends of the pair of guides 29 are located at the same position as the lower end of the protrusion 19 or located at a position downward of the lower end of the protrusion 19.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a snap-fit ​​structure technology that can be used, for example, in a housing that houses an electronic control device for a vehicle. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a housing in which a case and a cover are integrally combined has been known as a container for housing an electronic control device. A snap-fit ​​structure is also known as a structure for joining a case and a cover, in which a convex portion is provided on one member (e.g., the case) and a concave portion is provided on the other member (e.g., the cover), and the elasticity of the material is utilized to engage the convex portion with the concave portion, thereby joining the one member and the other member together.

[0003] For example, Patent Document 1 listed below discloses a snap-fit ​​structure for a housing using a metal cantilever beam with an opening and a resin case into which the cantilever beam is fitted, in which the side of the case is provided with a protrusion that fits into the opening of the cantilever beam and an L-shaped guide that guides both the left and right sides of the cantilever beam. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2002-134963 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, as a result of detailed investigation by the inventors, the following problems were found in the conventional techniques. For example, in a snap-fit ​​structure in which the case and the cantilever that fits into the case are made of resin, first, as shown in Figures 14A and 14B, the left and right sides of the cantilever (P1) of the cover are inserted into the L-shaped guides (P3) on the left and right of the case (P2), and the cantilever is pushed in the direction of the arrow Z.

[0006] Next, as shown in Fig. 14C, when the cantilever is further pushed in the direction of the arrow Z, the tip of the cantilever rides up onto the protrusion (P4) which is the latch, and the center portion bends greatly into a U-shape as shown in Fig. 14D. In other words, because the left and right sides of the cantilever are tightly restricted by the guide from moving in the thickness direction (i.e., the up and down direction in Fig. 13D), the center portion of the cantilever bends greatly to convex downward in Fig. 14D.

[0007] Furthermore, as shown in Figures 14E and 14F, when the cantilever is pushed in the direction of arrow Z, the tip of the cantilever transfers to the protrusion, and the protrusion fits into the opening (P5) of the cantilever, and the cantilever and the case are joined together.

[0008] By the way, when a cantilever with an opening is manufactured from resin, a weld line (WL) is likely to occur at the tip side. In other words, when a gate is placed at one point in the center of the product (for example, the center of the lid of a cover with a cantilever on the side) in order to reduce mold costs, a weld line often occurs at the tip side of the cantilever. Therefore, as shown in Figures 14C and 14D, when the resin cantilever passes over the protrusion, it bends significantly near the weld line, which causes a problem that the cantilever is likely to crack at or near the weld line. If the cantilever cracks, the initial holding force decreases.

[0009] Even if the cantilever does not break when it passes over the protrusion, it may bend significantly near the weld line, causing the tip of the cantilever to turn white and lose strength. In that case, even after the protrusion fits into the opening of the cantilever, if the cantilever or the case receives an external force (for example, an external force that causes the protrusion to come out of the opening), the cantilever is likely to break at the weld line.

[0010] For example, when an impact is applied to a cantilever or the like, the periphery of the opening shifts to the left or right in FIG. 14E (i.e., opens sideways), making it easier for the cantilever to come loose (i.e., detach from the protrusion).

[0011] An object of one aspect of the present disclosure is to provide a technique relating to a snap-fit ​​structure that can suppress damage such as cracking of a cantilever beam and can also suppress detachment of the cantilever beam. [Means for solving the problem]

[0012] One aspect of the present disclosure is a snap-fit ​​structure that connects the first part (5) and the second part (3). In this snap-fit ​​structure, the first part has a cantilever (17) that is flexible and extends from the fixed end to the free end, and the cantilever has a locking portion (21) that is used to connect with the second part. The second part also has a protrusion (19) that locks with the locking portion to restrict the movement of the cantilever, and a pair of guides (29) that guide the cantilever in a predetermined locking direction (i.e., the direction in which it moves to lock). The pair of guides are configured to cover both side portions (23) in the width direction, which is perpendicular to the extension and bending directions of the cantilever, on the free end side of the cantilever.

[0013] When the locking portion is locked, with the free end side of the cantilever beam on the lower side and the fixed end side on the upper side, the upper ends of the pair of guides are located at the same position as the lower end of the protrusion portion or at a position lower than the lower end of the protrusion portion.

[0014] With such a configuration, the snap-fit ​​structure of the present disclosure can prevent damage such as cracking of the cantilever beam, and can also prevent the cantilever beam from coming off the protrusion.

[0015] When a first part and a second part are joined by a snap-fit ​​structure, for example, if the cantilever of the first part is pushed into the protrusion of the second part, the cantilever rides up onto the protrusion, but at this stage, the cantilever does not bend significantly because both sides of the cantilever are not restricted by the pair of guides. In other words, the cantilever rides up onto the protrusion, but at this stage, the cantilever is bent at its base.

[0016] Thereafter, when the cantilever passes over the protrusion, both sides of the free end of the cantilever (i.e., the tip side) come into contact with a pair of guides and are guided by the pair of guides in a predetermined engagement direction (e.g., the gap between the guide and the wall surface on which the protrusion is provided: the inside of the guide), and at that time, the free end of the cantilever is guided inside the guide with only a slight bending compared to conventional methods or without bending at all.

[0017] Thus, according to the present disclosure, when the cantilever rides over the protrusion, it does not bend significantly as in the past, so even if the cantilever is made of resin and has a weld line on the free end side, the free end side of the cantilever is less likely to crack. Even if it does not crack, the strength is less likely to deteriorate due to whitening.

[0018] In addition, because the cantilever is less likely to crack, abnormal wear is less likely to occur in the cantilever even when vibrations are applied to the various components, etc. Moreover, even if an impact is applied to the cantilever, etc., the periphery of the locking portion (for example, the opening) opens sideways, preventing the cantilever from coming off the protrusion.

[0019] Therefore, the snap-fit ​​structure of the present disclosure can prevent damage such as cracking of the cantilever beam and can also prevent the cantilever beam from coming off, thereby achieving the remarkable effect of achieving good connection between the first part and the second part.

[0020] Furthermore, the symbols in parentheses in this column and in the claims indicate a correspondence with the specific means described in the embodiments described later as one aspect, and do not limit the technical scope of the present disclosure. [Brief description of the drawings]

[0021] [Figure 1] FIG. 2 is an exploded perspective view of a housing according to the first embodiment. [Diagram 2] FIG. 2 is an enlarged perspective view showing a snap-fit ​​structure of the first embodiment. [Diagram 3] FIG. 3A is a front view showing a cantilever beam of the first embodiment, and FIG. 3B is a cross-sectional view taken along line IIIB-IIIB of FIG. 3A. [Figure 4] 4A is a plan view showing the protrusions etc. of the first embodiment, FIG. 4B is a front view of the protrusions etc., FIG. 4C is a side view of the protrusions etc., and FIG. 4D is a front view of the protrusions etc. of a modified example. [Diagram 5] FIG. 5A is a plan view showing the guide etc. of the first embodiment, FIG. 5B is a front view of the guide etc., and FIG. 5C is a side view of the guide etc. [Figure 6] 3B is an explanatory diagram showing the positional relationship between the cantilever beam, the guide, and the protrusion portion in the first embodiment in the IIIB-IIIB cross section of FIG. 3A. [Figure 7] The steps for joining the case and cover in the first embodiment are shown in FIG. 7A, where FIG. 7B is a cross-sectional view taken along line VIIB-VIIB of FIG. 7A, FIG. 7C is a front view of the cantilever beams etc. in the next step, FIG. 7D is a cross-sectional view taken along line VIID-VIID of FIG. 7C, FIG. 7E is a cross-sectional view taken along line VIIE-VIIE of FIG. 7C, FIG. 7F is a front view of the cantilever beams etc. in the next step, and FIG. 7G is a cross-sectional view taken along line VIIF-VIIF of FIG. 7F. [Figure 8] FIG. 8A is a front view showing a cantilever beam of the second embodiment, and FIG. 8B is a cross-sectional view taken along line VIIIB-VIIIB of FIG. 8A. [Figure 9] 8B is an explanatory diagram showing the positional relationship between the cantilever and the protrusion in the second embodiment in the VIIIB-VIIIB cross section of FIG. 8A. [Figure 10]FIG. 11 is a plan view showing a cantilever beam of a modified example of the second embodiment cut along the ZX plane and its surrounding structure. [Figure 11] 11A is a plan view showing a snap-fit ​​structure of the third embodiment from the inside of a housing, and FIG. 11B is a cross-sectional view taken along line XIB-XIB of FIG. 11A. [Figure 12] 12A is a plan view showing a snap-fit ​​structure of the fourth embodiment from the inside of a housing, and FIG. 12B is a cross-sectional view taken along line XIIB-XIIB of FIG. 12A. [Figure 13] FIG. 13A is a plan view showing protrusions etc. of another embodiment, FIG. 13B is a front view of the protrusions etc., and FIG. 13C is a side view of the protrusions etc. [Figure 14] FIG. 1 is an explanatory diagram of a conventional technique. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First embodiment] [1-1. Overall composition] As shown in FIG. 1, the housing 1 of the first embodiment is a container having a box-shaped case 3 and a box-shaped cover 5 that fits inside the case 3, and the case 3 and the cover 5 can be joined together by a snap-fit ​​structure described later.

[0023] The case 3 is made of resin (for example, the resin is PBT). Note that PBT is polybutylene terephthalate. The case 3 is a container that has a substantially rectangular parallelepiped shape and is open upward in the Z-axis direction.

[0024] In detail, the case 3 includes a flat bottom 7 arranged along the XY plane, and rectangular frame-like case side parts 9 arranged vertically from the bottom 7 (e.g., arranged upward in FIG. 1) along the outer periphery of the bottom 7. The case side parts 9 are long plate-like members arranged in a strip shape surrounding the periphery of the bottom 7 so as to be perpendicular to the bottom 7.

[0025] As will be described in detail later, case engagement parts 11 constituting part of the snap-fit ​​structure are provided at multiple locations (e.g., six locations) on the inside of the case side part 9. Note that only some of the case engagement parts 11 (i.e., three locations) are shown in Fig. 1.

[0026] The cover 5 is a container that is fitted inside the case 3 on the opening 12 side of the case 3 so as to close the opening 12. The cover 5 is made of resin (for example, the resin is PBT). The cover 5 is a container that has a substantially rectangular parallelepiped shape and is open downward in the Z-axis direction.

[0027] In detail, the cover 5 includes a plate-like lid portion 13 arranged along the XY plane, and a rectangular frame-like cover side portion 15 arranged vertically from the lid portion 13 (for example, arranged downward in FIG. 1) along the outer periphery of the lid portion 13. The cover side portion 15 is a long plate-like member arranged in a strip shape surrounding the periphery of the lid portion 13 so as to be perpendicular to the lid portion 13.

[0028] Cover engagement parts 16 constituting part of the snap-fit ​​structure are provided at multiple locations (e.g., six locations) on the cover side part 15. Note that only some of the cover engagement parts 16 (i.e., three locations) are shown in Fig. 1.

[0029] In the first embodiment, each case engaging portion 11 and each cover engaging portion 16 engage with each other (i.e., engage with each other) to integrally connect the case 3 and the cover 5. In detail, by utilizing the elasticity of the material (e.g., the elasticity of the cover 5), one of the engaging members stops (i.e., locks) the other, thereby forming a snap-fit ​​structure to integrally connect the case 3 and the cover 5.

[0030] In the XYZ coordinate system, the vertical direction in FIG. 1 (i.e., the thickness direction of the housing 1) is the Z-axis direction, and when viewed from the Z-axis direction, the longitudinal direction of the housing 1 is the X-axis direction and the short direction is the Y-axis direction.

[0031] Each configuration will be described in detail below. [1-2. Snap-fit ​​structure] Next, the snap-fit ​​structure will be described with reference to Fig. 2 and other figures. Note that the six snap-fit ​​structures are basically the same, so a snap-fit ​​structure at one location will be described as an example. Note that Fig. 2 shows an enlarged view of the snap-fit ​​structure arranged on the long side of the housing 1 as viewed from inside the housing 1.

[0032] As shown in FIG. 2, the snap-fit ​​structure includes a case engaging portion 11 and a cover engaging portion 16. As shown in FIG. <Cover engagement part> The cover engagement portion 16 is provided with a cantilever 17 extending from one end of the cover side portion 15 along the erection direction of the cover side portion 15 to the opposite side of the lid portion 13 (i.e., the side of the bottom portion 7 of the case 3 to which it is joined). Note that the cover side portion 15 has rectangular notches 25 formed along the left and right side portions 23 of the cantilever 17 so that the cantilever 17 can be easily bent.

[0033] The cantilever 17 is a rectangular member (i.e., a rectangular shape when viewed from the Y-axis direction) that spreads along the ZX plane from one end of the cover side portion 15. That is, the cantilever 17 is a plate-like member that has one end of the cover side portion 15 as a fixed end and extends downward in FIG. 2 from the fixed end to a free end.

[0034] As shown in FIG. 3A, an opening 21 is provided on the free end side (i.e., the tip side) of the cantilever 17 to be engaged with a protrusion 19 (see, for example, FIG. 2) which is a latch described later. This opening 21 is a through hole that penetrates the cantilever 17 in the thickness direction (i.e., the plate thickness direction which is the Y-axis direction). The shape of the opening 21 is, for example, approximately rectangular when viewed from the Y-axis direction, but the side on the fixed end side (i.e., the base side) is curved into an approximately semicircular shape. The shape of the opening 21 may be rectangular.

[0035] 3B, the free end side of the cantilever 17, i.e., tip portion 27 on the tip side of the opening 21, has a thickness dimension that decreases toward the tip side. In other words, tip portion 27 has a tapered portion 28 that is tapered when viewed from the X-axis direction.

[0036] In addition, the left and right direction in the X-axis direction in Figure 3A is the width direction of cantilever beam 17, the direction perpendicular to the width direction (i.e., the Z-axis direction) is the direction in which cantilever beam 17 extends, and the Y-axis direction is the direction in which cantilever beam 17 bends (i.e., the plate thickness direction).

[0037] <Case engagement part> As shown in FIG. 2, the case engagement portion 11 includes a protrusion 19 configured to fit into the opening 21, and a pair of left and right guides 29 configured to guide the left and right side portions 23 of the cantilever beam 17.

[0038] Of these, the protrusion 19 is a locking member that engages with the opening 21, more specifically, with a part of the inner surface 21a of the opening 21 (i.e., the lower surface of the inner surface 21a in Figure 2), thereby restricting the movement of the cantilever 17 upward in Figure 2 (i.e., in the direction in which the cantilever 17 comes off).

[0039] This protrusion 19 is generally wedge-shaped such that the thickness of the rear end side (i.e., the upper side in FIG. 2: the opening 12 side of the case 3) is thinner than the tip side (i.e., the lower side in FIG. 2: the bottom 7 side of the case 3). Specifically, as shown in Figures 4A to 4C, the protrusion 19 has a rectangular prism-shaped tip portion 31 and a triangular prism-shaped inclined portion 33 connected to the rear end side of the tip portion 31 (i.e., the upper side in Figure 4B).

[0040] As a result, as shown in Fig. 4C, the top surface 31a of the tip portion 31 of the protrusion 19 protrudes highest above the inner peripheral surface 9a of the case side portion 9, and the height of the inclined surface (i.e., the protrusion-side inclined surface) 35 of the inclined portion 33 gradually decreases from the surface 31a toward the rear end. In other words, the protrusion-side inclined surface 35 is inclined at a predetermined angle α, which will be described later. Note that α is within a predetermined range in which the cantilever beam 17 can be engaged, within the range of "0°<α<90°", as will be described later.

[0041] As another shape of the protrusion 19, for example, as shown in Fig. 4D, the planar shape of the inclined portion 33 (i.e., the shape as viewed from the Y-axis direction) may be a circle or an ellipse curved to be convex toward the rear end side. In this case, the planar shape of the opening 21 may also be a shape that follows the outer periphery of the protrusion 19.

[0042] <Guide> Next, the pair of guides 29 will be described. 2, the pair of guides 29 are members that guide the cantilever 17 in a predetermined locking direction (i.e., the direction in which the cantilever 17 is moved when locked: downward in FIG. 2). The pair of guides 29 are configured to cover both side portions 23 in the width direction, which is perpendicular to the extension direction (i.e., Z-axis direction) and bending direction (i.e., Y-axis direction) of the cantilever 17 on the free end side of the cantilever 17 (i.e., X-direction).

[0043] In addition, since the pair of guides 29 are symmetrical (for example, line symmetrical when viewed from the Z-axis direction), the following description will be given taking one of the guides 29 (for example, the left side in FIG. 2) as an example. As shown in FIG. 5, the guide 29 is a columnar member provided to extend in the Z-axis direction along the case side portion 9 from the bottom portion 7 of the case 3, and has an L-shape when viewed from the Z-axis direction.

[0044] In detail, the guide 29 is composed of a plate-shaped first restricting portion 37 and a plate-shaped second restricting portion 39, and the first restricting portion 37 and the second restricting portion 39 are connected perpendicularly when viewed from the Z-axis direction, thereby forming the L-shape. In the first embodiment, the first restricting portion 37 and the second restricting portion 39 are integrally formed.

[0045] Of these, the second restricting portions 39 are members that are provided on the surfaces of the bottom portion 7 and the case side portion 9 perpendicularly to the bottom portion 7 and the case side portion 9. The second restricting portions 39 restrict the movement of the cantilever beam 17 in the width direction. In other words, the left and right second restricting portions 39 of the pair of guides 29 restrict the movement of the cantilever beam 17 in the directions in which the left and right side portions 23 of the opening portion 21 open.

[0046] On the other hand, the first restricting portion 37 is a member that is provided vertically with respect to the bottom portion 7 and the second restricting portion 39 at the bottom portion 7 and the second restricting portion 39. The first restricting portion 37 restricts the movement of the cantilever beam 17 in the bending direction (for example, the left direction in FIG. 5C).

[0047] As shown enlarged in Figure 6, a guide side inclined surface 41 is provided on the inside (i.e., right side of Figure 6) of the tip side (i.e., upper side of Figure 6) of the first regulating portion 37, which is inclined so that the distance between the first regulating portion 37 and the case side portion 9 becomes narrower as it approaches the rear end side (i.e., lower side of Figure 6) of the first regulating portion 37.

[0048] The guide-side inclined surface 41 is a plane inclined at a predetermined angle β with respect to the direction in which the cantilever 17 extends (i.e., the Z-axis direction) when the cantilever 17 is engaged with the protrusion 19, more specifically, with respect to the direction in which the cantilever 17 spreads (i.e., the ZX plane). Note that β is within a predetermined range in which the cantilever 17 can be guided, within the range of "0°<β<90°", as described later.

[0049] In other words, as described below, when the cantilever beam 17 moves over the protrusion 19 and hits the guide 29 when the case 3 and the cover 5 are joined, the guide side inclined surface 41 is a surface that is inclined so that the right side in Figure 6 slopes downward relative to the engagement direction so as to guide the free end side in a direction covered by the guide 29 (i.e., the engagement direction, which is downward in Figure 6).

[0050] Particularly, in the first embodiment, the upper end of guide 29 is provided at a position lower than the lower end of protrusion 19. That is, in the Z-axis direction, there is a gap of Δx between the upper end of guide 29 (i.e., the upper end of guide-side inclined surface 41) and the lower end of protrusion 19. Note that the position of the upper end of guide 29 and the position of the lower end of protrusion 19 may be the same.

[0051] The range of Δx can be set appropriately within the range in which, when the cantilever 17 is engaged with the protrusion 19, the tip 27 of the cantilever 17 hits the guide 29 (e.g., the guide side inclined surface 41) and the cantilever 17 can be guided downward in Figure 6 (i.e., in the engagement direction of the cantilever 17).

[0052] Furthermore, in this first embodiment, when viewed from the X-axis direction, the guide side inclined surface 41 of the guide 29 is configured to exist on the extension line of the protrusion side inclined surface 35 of the inclined portion 33 of the protrusion portion 19 (i.e., see the dashed arrow in Figure 6).

[0053] [1-3. Joining method] Next, a method for joining the case 3 and the cover 5 will be described with reference to FIG. In addition, FIG. 7 shows the configuration of each part in a schematic manner, and the shape of protrusion 19 shown in FIG. 4D is taken as an example.

[0054] As shown in Figures 7A and 7B, first, cover 5 is fitted so as to cover the opening 12 side of case 3, and cantilever beam 17 of cover 5 is moved in the direction of arrow Z (i.e., the locking direction) along case side 9.

[0055] 7C and 7D, cantilever 17 is further pushed in the direction of arrow Z so that the tip side (i.e., the free end side) of cantilever 17 rides up onto protrusion 19. That is, tip 27 of cantilever 17 moves on protrusion-side inclined surface 35. At this time, the rear end side (i.e., the fixed end side) of cantilever 17 is bent and the tip side is raised as shown in FIG. 7E.

[0056] In this state, if the cantilever 17 is pushed further in, the tip 27 of the cantilever 17 comes into contact with the guide side inclined surface 41 of the guide 29, and the tip 27 of the cantilever 17 moves in the engagement direction and is guided into the gap between the guide side inclined surface 41 and the inner surface 9a of the case side portion 9.

[0057] In other words, the pair of guides 29 covers both widthwise sides 23 of the cantilever 17 and restricts movement of the cantilever 17 to the left in FIG. 7E, thereby guiding the cantilever 17 downward in FIG. 7E.

[0058] Thereafter, when cantilever 17 is further pushed in, as shown in Figures 7F and 7G, tip 27 of cantilever 17 transfers to protrusion 19, and protrusion 19 fits into opening 21 of cantilever 17. In other words, opening 21 is locked by protrusion 19, and cantilever 17 itself is also locked by protrusion 19, and is fixed so as not to come off.

[0059] This allows the case 3 and the cover 5 to be joined together. [1-4. Effects] According to the first embodiment, the following effects can be obtained.

[0060] (1a) In the first embodiment, the case 3 and the cover 5 are made of resin, and the upper ends of the pair of guides 29 are located below the lower ends of the protrusions 19, as shown in FIG.

[0061] Therefore, when the cantilever 17 rides on the protrusion 19, it does not bend significantly as in the past, so even if there is a weld line on the free end side of the resin cantilever 17, the free end side of the cantilever 17 is unlikely to crack. Even if it does not crack, the strength is unlikely to deteriorate due to whitening.

[0062] In addition, since the cantilever 17 is unlikely to crack, abnormal wear is unlikely to occur in the cantilever 17, etc., even when vibration is applied to the housing 1, etc. Moreover, even when an impact is applied to the cantilever 17, etc., it is possible to prevent the tip 27 adjacent to the opening 21 from cracking, causing the periphery of the opening 21 to open sideways, and causing the cantilever 17 to come off the protrusion 19.

[0063] Therefore, in the first embodiment, damage to the cantilever 17 can be suppressed, and the cantilever 17 can be suppressed from coming off the protrusion 19, thereby achieving the remarkable effect of achieving good connection between the case 3 and the cover 5.

[0064] In addition, in the first embodiment, the height of guide 29 can be set low by providing the upper end of guide 29 at a position lower than the lower end of protrusion 19. Therefore, even when a large board is housed in housing 1, there is an advantage that the board and guide 29 are unlikely to interfere with each other.

[0065] (1b) In the first embodiment, the pair of left and right guides 29 are configured to restrict movement of the cantilever 17 in the bending direction and to restrict movement of the cantilever 17 in the width direction. With this configuration, it is possible to effectively prevent the cantilever 17 from coming off the protrusion 19.

[0066] (1c) In the first embodiment, the free end side of the cantilever 17 is provided with a tapered portion 28 that becomes thinner toward the free end side. Therefore, when the cantilever 17 is pressed in, the tip 27 of the cantilever 17 can move smoothly over the protrusion 19. Furthermore, when the tip 27 of the cantilever 17 hits the guide 29, the tip 27 of the cantilever 17 can move smoothly in a direction covered by the guide 29 (for example, in the downward engaging direction in FIG. 6).

[0067] (1d) In the first embodiment, the guide 29 is provided with a guide-side inclined surface 41 at a portion where the tip 27 of the cantilever 17 abuts. Therefore, when the tip 27 of the cantilever 17 abuts against the guide-side inclined surface 41, the tip 27 of the cantilever 17 can be smoothly guided in a predetermined movement direction.

[0068] (1e) In the first embodiment, the guide-side inclined surface 41 of the guide 29 is present on an extension of the protrusion-side inclined surface 35 of the inclined portion 33 of the protrusion 19. This ensures that the tip 27 of the cantilever 17 hits the guide-side inclined surface 41 when the cantilever 17 is pushed in and engaged with the protrusion 19, so that the cantilever 17 can be guided appropriately.

[0069] [1-5. Correspondence] Next, the relationship between the first embodiment and the present disclosure will be described. The housing 1 corresponds to the housing, the case 3 corresponds to the second part, the cover 5 corresponds to the first part, the cantilever 17 corresponds to the cantilever, the protrusion 19 corresponds to the protrusion, the opening 21 corresponds to the locking part, the side 23 corresponds to the side, the inclined part 33 corresponds to the inclined part, the guide 29 corresponds to the guide, the protrusion side inclined surface 35 corresponds to the protrusion side inclined surface, and the guide side inclined surface 41 corresponds to the guide side inclined surface 41.

[0070] [2. Second embodiment] Since the second embodiment has a basic configuration similar to that of the first embodiment, the following mainly describes the differences from the first embodiment. Note that the same reference numerals as those in the first embodiment indicate the same configuration, and the preceding description is to be referred to.

[0071] In the snap-fit ​​structure of the second embodiment, the configuration of the cantilever beam 51 is significantly different from that of the first embodiment, as shown in Fig. 8. The following description will focus on the differences. Specifically, the cantilever beam 51 used in the second embodiment is provided with a recess 53 instead of an opening so as to be engaged with the protrusion 19.

[0072] This recess 53 is provided in a strip shape on the outside of the cantilever 51, i.e., on the side of the case side 9 where the protrusion 19 is provided (for example, the right side of Figure 8B), from the upper side of the cantilever 51 (i.e., the upper end portion of the cover side 15) to the tip 55 of the cantilever 51.

[0073] That is, the recess 53 is a rectangular groove cut into a rectangular parallelepiped shape so as to have a certain depth when viewed from the Y-axis direction. As shown in Fig. 8B, the upper end of the recess 53 is provided up to the lid portion 13 of the cover 5, and the tip surface 53a of the recess 53 is formed so as to be perpendicular to the bottom surface 53b.

[0074] 9, when the cantilever 51 moves in the direction of the arrow Z, the tip 55 of the cantilever 51 climbs over the protrusion 19, and the protrusion 19 fits into the recess 53. As a result, the recess 53 (i.e., the tip surface 53a of the recess 53) is engaged with the protrusion 19, and the cantilever 51 is fixed to the protrusion 19.

[0075] The second embodiment provides the same effects as the first embodiment. In the second embodiment, when a resin cover 5 is manufactured using a metal mold, the upper and lower dies can be separated, so that the manufacturing process can be simplified.

[0076] In this second embodiment, when the cover 5 is fitted to the case 3, it is possible to visually check from the lid portion 13 side of the cover 5 whether the protrusion portion 19 is engaged with the recess 53 of the cantilever beam 17.

[0077] In this second embodiment, when the cover 5 is fitted to the case 3, the recess 53 of the cantilever 17 has a bag structure with no opening that opens to the inside of the housing 1, so that even if water gets into the gap between the cantilever 17 and the case side 9, the water is less likely to enter the inside of the housing 1.

[0078] <Modification> As shown in FIG. 10, a pair of left and right crush ribs 57 may be provided on the inner side of the cantilever beam 51 (that is, on the inner side of the cover 5).

[0079] Specifically, the crush rib 57 is provided in a convex shape on the inside of the cantilever beam 51, on the inside of the left and right side portions 59, i.e., on the portions facing the first restricting portions 37 of the left and right guides 29, so as to reach the first restricting portions 37. The crush rib 57 is provided on the inside of the cantilever beam 51, along the Y-axis direction, so as to reach from the upper end to the lower end of the cantilever beam 51. The thickness (i.e., the dimension in the Y-axis direction) of the crush rib 57 is set so as to slightly press the first restricting portions 37.

[0080] By providing the crush rib 57 in this manner, the crush rib 57 and the first restriction portion 37 are in close contact with each other in a pressed state, improving the close contact between the cover 5 and the case 3. This can suppress the generation of abnormal noise. Also, waterproofing can be improved.

[0081] [3. Third embodiment] Since the third embodiment has a basic configuration similar to that of the first embodiment, the following description will mainly focus on the differences from the first embodiment. Note that the same reference numerals as those in the first embodiment indicate the same configurations, and the preceding description will be referred to.

[0082] In the snap-fit ​​structure of the third embodiment, as shown in FIG. 11, a pair of left and right guides 61 each have a first regulating portion 63 and a second regulating portion 65, but the first regulating portion 63 and the second regulating portion 65 of each guide 61 are configured separately.

[0083] In other words, in the third embodiment, a first regulating portion 63 that regulates movement of the cantilever beam 17 in the bending direction (i.e., the up-down direction in FIG. 11B) and a second regulating portion 65 that regulates movement of the cantilever beam 17 in the width direction (i.e., the left-right direction in FIG. 11B) are provided at different positions.

[0084] The first restricting portion 63 is a plate-like member that stands vertically from the bottom portion 7 of the case 3 toward the upper side in FIG. 11A, and is disposed parallel to the case side portion 9. The thickness direction of the first restricting portion 63 is the same as the bending direction of the cantilever beam 17, and the tip side of the first restricting portion 63 can bend in the same direction as the cantilever beam 17. A guide-side inclined surface 67 that is inclined similarly to the first embodiment is provided on the inside of the tip of the first restricting portion 63 (i.e., the upper side in FIG. 11B).

[0085] 11A from the bottom 7 of the case 3, and are disposed outside the left and right side portions 23 of the cantilever beam 17. The pair of left and right second restricting portions 65 are disposed in parallel to each other.

[0086] The third embodiment provides the same effects as the first embodiment. Furthermore, in the third embodiment, the cantilever 17 can be easily locked, and the cantilever 17 locked to the protrusion 19 is unlikely to come off.

[0087] Specifically, since the first restricting portion 63 is a cantilever having flexibility as described above, for example, if the distance between the first restricting portion 63 and the case side portion 9 is arranged narrower than in the first embodiment, when the tip portion 27 of the cantilever 17 hits the guide side inclined surface 67 of the first restricting portion 63 when the cantilever 17 is pushed in, the tip side of the first restricting portion 63 bends slightly away from the case side portion 9 (i.e., opens).

[0088] Thereafter, when the cantilever 17 is further pushed in, it advances while being guided by the first restricting portion 63, and the protrusion 19 fits into the opening 21, and the cantilever 17 is locked by the protrusion 19. At this time, the tip 27 of the cantilever 17 approaches or comes into contact with the case side portion 9, so that the first restricting portion 63 returns to its original bending state and becomes straight.

[0089] With this configuration, when the cantilever beam 17 is pushed in, the tip side of the first regulating portion 63 bends, so that the cantilever beam 17 can be easily pushed in, and therefore the cantilever beam 17 can be easily engaged.

[0090] In addition, after the cantilever 17 is locked, the downward movement of the cantilever 17 in FIG. 11B is restricted by the first restricting portion 63 which has returned to its original deflection, so that the cantilever 17 is even less likely to fall off the protruding portion 19.

[0091] [4. Fourth embodiment] Since the fourth embodiment has a basic configuration similar to that of the first embodiment, the following description will mainly focus on the differences from the first embodiment. Note that the same reference numerals as those in the first embodiment indicate the same configurations, and the preceding description will be referred to.

[0092] In the snap-fit ​​structure of the fourth embodiment, as shown in FIG. 12, each guide 71 is not L-shaped as in the first embodiment, but has a substantially flat plate shape. In the fourth embodiment, a plate-like guide 71 is provided vertically upward from the bottom 7 of the case 3 in FIG. 12A.

[0093] The guides 71 are disposed at an angle to the case side 9. That is, the left and right guides 71 are disposed in a substantially V-shaped position such that the distance between them decreases as the guides are farther from the case side 9. That is, the guides 71 are configured to restrict movement of the cantilever 17 in the bending direction (i.e., downward in FIG. 12B) and to restrict movement of the cantilever 17 in the width direction (i.e., left and right direction in FIG. 12B).

[0094] Incidentally, on the inside of the tip of the guide 71 (that is, on the protrusion 19 side), a guide-side inclined surface 73 is provided which is inclined in the same manner as in the first embodiment. The fourth embodiment has the same effects as the first embodiment, and further has a simplified configuration and can reduce the amount of material used.

[0095] 5. Other embodiments Although the embodiments of the present disclosure have been described above, it goes without saying that the present disclosure is not limited to the above-described embodiments and can take various forms.

[0096] (5a) For example, if the cantilever beam can be guided by a guide, it is possible to omit the inclined surface or tapered portion on the guide side. (5b) The shapes and arrangements of each component, such as the guide, protrusion, cantilever, etc., may be of various shapes and arrangements as long as the effects of the present disclosure are achieved.

[0097] 13, the guide 29 of the first embodiment may be configured such that a part of the first restricting portion 37 on the case side 9 side (i.e., the lower side in FIG. 13C) reaches the case side 9. In other words, when the cantilever 17 is engaged with the protrusion 19, there may be no gap between the first restricting portion 37 and the case side 9 on the tip side of the tip of the cantilever 17 (i.e., the lower side in FIG. 13C).

[0098] (5c) Examples of materials for resin cases and covers include materials made of resin or materials made of resin with additives added. For example, a material with the largest proportion of resin (i.e., a material mainly composed of resin) can be used.

[0099] (5d) Multiple functions possessed by one component in each of the above embodiments may be realized by multiple components, or one function possessed by one component may be realized by multiple components. Also, multiple functions possessed by multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. Also, part of the configuration of the above embodiments may be omitted. Also, at least part of the configuration of the above embodiments may be added to or substituted for the configuration of another embodiment. [Explanation of symbols]

[0100] 1...housing, 3...case, 5...cover, 17, 51...cantilever, 19...projection, 21...opening, 23...side, 29, 61, 71...guide, 33...inclined portion, 35...projection side inclined surface, 41, 61...guide side inclined surface

Claims

1. A snap-fit ​​structure for connecting a first part (5) and a second part (3), The first component includes a cantilever (17) having flexibility and extending from a fixed end side to a free end side, and the cantilever includes a locking portion (21) used for coupling with the second component; The second part includes a protrusion (19) that engages with the engaging portion to restrict movement of the cantilever beam, and a pair of guides (29) that guide the cantilever beam in a predetermined engaging direction, The pair of guides are configured to cover both side portions (23) in a width direction perpendicular to the extending direction and bending direction of the cantilever beam at the free end side of the cantilever beam, when the locking portion is locked, and when the free end side of the cantilever beam is the lower side and the fixed end side is the upper side, upper ends of the pair of guides are provided at the same position as the lower end of the protrusion or at a position lower than the lower end of the protrusion, When the first part and the second part are joined, in the case where the free end side of the cantilever moves on the protrusion and hits the pair of guides, a guide side inclined surface (41) inclined with respect to the locking direction is provided at the portion where the free end side of the pair of guides hits so as to guide the free end side in the locking direction. Snap fit construction.

2. The snap-fit ​​structure according to claim 1, The protrusion has an inclined portion (33) whose thickness decreases toward the upper side, The guide-side inclined surfaces of the pair of guides are configured to exist on an extension line of a protrusion-side inclined surface (35) which is an inclined surface of the inclined portion. Snap fit construction.

3. The snap-fit ​​structure according to claim 1 or 2, The locking portion is a through hole or a recess provided in the cantilever beam. Snap fit construction.

4. A snap-fit ​​structure according to any one of claims 1 to 3, At least one of the pair of guides is configured to restrict movement of the cantilever beam in the bending direction and to restrict movement of the cantilever beam in the width direction. Snap fit construction.

5. A snap-fit ​​structure according to any one of claims 1 to 3, At least one of the pair of guides includes a first regulating portion (63) that regulates the movement of the cantilever beam in the bending direction, and a second regulating portion (65) that is configured separately from the first regulating portion and regulates the movement of the cantilever beam in the width direction. Snap fit construction.

6. A snap-fit ​​structure according to any one of claims 1 to 5, A tapered portion (28) is provided on the free end side of the cantilever beam, the thickness of which decreases toward the free end side. Snap fit construction.

7. A snap-fit ​​structure according to any one of claims 1 to 6, The first part and the second part are made of resin. Snap fit construction.

8. A snap-fit ​​structure according to any one of claims 1 to 7, Housing.

Images