Electrical junction box

Abstract

Electrical connection box (1) comprising: an electronic component (6b, 6c); a block (5) having a first side surface (5a, 5b) and a second side surface (5c, 5d) and holding the electronic component (6b, 6c); a cover (4) having a first inner wall surface (41a, 42a) facing the first side surface (5a, 5b) and a second inner wall surface (43a, 44a) facing the second side surface (5c, 5d), and covering the block (5) and the electronic component (6b, 6c) in an integrated manner; an engagement mechanism (9) including a projecting engagement portion (54) provided on one of the first side surface (5a, 5b) and the first inner wall surface (41a, 42a) and a recessed engagement portion (41b, 42b) provided on the other of the first side surface (5a, 5b) and the first inner wall surface (41a, 42a); a projection (55) provided on one surface of the second side surface (5c, 5d) and the second inner wall surface (43a, 44a) and configured to contact the other surface of the second side surface (5c, 5d) and the second inner wall surface (43a, 44a) so as to press against the other surface and deform the cover (4) inwardly so that the first side surface (5a, 5b) and the first inner wall surface (41a, 42a) approach each other and a deformation amount (u) increases from both ends toward a central part in the transverse direction of the first inner wall surface (41a, 42a), thereby preventing the first side surface (5a, 5b) and the first inner wall surface (41a, 42a) from relatively moving in directions diverging from each other in an engaged state of the engagement mechanism (9); and a frame holding an electronic component module (3) therein, which includes the electronic component (6b, 6c), the block (5) and the cover (4).

Description

Background of the invention 1. Field of the invention

[0001] The present invention relates to an electrical junction box. 2. Description of related technology

[0002] Engagement structures are known that each engage a block with a cover that covers the block and electronic components in an integrated manner. Japanese Patent Application Laid-Open No. JP 2011-193594 A discloses a technique of an electrical junction box that includes a housing provided with an opening that opens downward and accommodates a circuit board therein, and further includes a connector that is fitted to the housing and closes the opening. A locking portion that projects outwardly is provided on an outer wall of the connector. In the electrical junction box of Japanese Patent Application Laid-Open No.According to JP 2011-193 594 A, the locking portion elastically engages with a locking receiving portion formed in a side wall of the housing so that the connector is integrally fitted to the housing.

[0003] Document JP 2011-48995 A1 relates to a connector comprising a female connector housing and a male connector housing having a cylindrical fitting cylinder into which the fitting is formed by inserting the female connector housing. Fitting guide ribs extending along the fitting direction are protruding in the female connector housing and are provided on at least both sides. Fitting grooves mate with the guide ribs in the male connector housing are formed on the inner wall surface of the fitting cylinder.During fitting, the guide ribs penetrate into the fitting grooves while pushing the fitting cylinder outward, and at the same time, the inner wall surface of the housing of the male connector, which is different from the inner wall surfaces with the fitting grooves, is deformed inward to press the outer surface of the housing of the female connector into an elastically contacted state.

[0004] Document US 2013 / 0 170 160 A1 relates to an electronic device comprising a circuit substrate, a lower case, and an upper case. The circuit substrate has a plurality of slots penetrating it. The lower case has a groove portion positioned on an inner surface of the lower case such that edge portions of the circuit substrate are slidable and insertable into the groove portion. A plurality of pin-shaped projections are provided in the lower case, each projection having a plurality of locking portions at a tip end portion. Each projection elastically urges the circuit substrate toward the top of the lower case and presses the circuit substrate against an upper surface of the groove portion by locking the locking portions to the circuit substrate after the locking portions are respectively inserted into the slots. Overview of the invention

[0005] In the case where the block is engaged with the cover by an engagement mechanism such as the locking mechanism and the lock receiving mechanism described above, it is desirable to improve the reliability of the engagement mechanism. For example, the engagement state of the engagement mechanism can be desirably prevented from being released due to vibration or impact.

[0006] It is an object of the present invention to provide an electrical junction box capable of improving the reliability of the engagement mechanism.

[0007] The above object is achieved by an electrical connection box according to claim 1.

[0008] The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention in conjunction with the accompanying drawings. Short description of the drawings Fig. 1 is a perspective view of an electrical junction box according to an embodiment; Fig. 2 is a bottom view of the electrical connection box according to the embodiment; Fig. 3 is a perspective view of a circuit board and a connector block according to the embodiment; Fig. 4 is a plan view of the circuit board and the connector block according to the embodiment; Fig. 5 is a perspective cross-sectional view of a cover according to the embodiment; Fig. 6 is a cross-sectional view of an electronic component module according to the embodiment; Fig. 7 is a bottom view illustrating deformation of the cover; Fig. Fig. 8 is a cross-sectional view illustrating frame-side projections according to the embodiment; and Fig. 9 is another cross-sectional view illustrating the frame-side projection according to the embodiment. Detailed description of the preferred embodiment

[0009] An engaging structure, an electronic component module, and an electrical connection box according to an embodiment of the present invention will be described in detail below with reference to the drawings. This embodiment does not limit the present invention. Components in the following embodiment include those easily conceived by those skilled in the art and those that are substantially the same. Embodiment

[0010] The embodiment will be described with reference to Fig. 1 to Fig. 9. The present embodiment relates to the electrical junction box. Fig. 1 is a perspective view of the electrical connection box according to the embodiment; Fig. 2 is a bottom view of the electrical connection box according to the embodiment; Fig. 3 is a perspective view of a circuit board and a connector block according to the embodiment; Fig. 4 is a plan view of the circuit board and the connector block according to the embodiment; Fig. 5 is a perspective cross-sectional view of a cover according to the embodiment; Fig. 6 is a cross-sectional view of an electronic component module according to the embodiment; Fig. 7 is a bottom view illustrating deformation of the cover; Fig. Fig. 8 is a cross-sectional view illustrating frame-side projections according to the embodiment; and Fig. 9 is another cross-sectional view illustrating one of the frame-side projections according to the embodiment. Fig. 5 is a cross-sectional view of Fig. 1 along line VV; Fig. 6 is a cross-sectional view of Fig. 1 along line VI-VI; Fig. 8 is a cross-sectional view of Fig. 1 along line VIII-VIII; and Fig. 9 is a cross-sectional view of Fig. 8 along line IX-IX.

[0011] As in Fig. 1, an electrical junction box 1 according to the present embodiment includes a frame 2 and an electronic component module 3. In the present embodiment, the electrical junction box 1 will be described using an example in which the electrical junction box 1 is mounted on a vehicle. The electrical junction box 1 forms a wire harness WH together with electrical wires W. The wire harness WH is mounted on the vehicle such as an automobile and connects devices mounted on the vehicle to each other. The wire harness WH includes the electrical wires W used for power supply and signal transmission. One end of each of the electrical wires W is connected to the electronic component module 3 housed in the electrical junction box 1.The other end of each of the electric wires W is connected to a corresponding device (external equipment) such as a battery or an electrical component through a connector and the like.

[0012] The electronic component module 3 includes an engagement structure 100, which will be described below, and can improve the reliability of an engagement mechanism 9. The engagement structure 100 can prevent rattling of a substrate 6 (see Fig. 3 and Fig. 6) on a cover 4. The engagement structure 100 includes a connector block 5, the cover 4, the engagement mechanism 9 and projections 55 (see Fig. 3). The electronic component module 3 contains electronic components (such as resistors 6b and relays 6c, which are Fig. 3) and the intervention structure 100.

[0013] The Fig. 1 and Fig. The frame 2 illustrated in Figure 2 holds the electronic component module 3 therein. The frame 2 is integrally formed, for example, from a synthetic resin. The frame 2 is a tubular member, and its planar shape is, for example, a polygonal shape such as a rectangular shape. The electronic component module 3 is inserted into the frame 2 from an opening of the frame 2 or withdrawn from the frame 2. The electrical connection box 1 includes an upper cover and a lower cover (both not shown) that close the openings of the frame 2. The frame 2, together with the upper cover and the lower cover, forms a closed receiving space for receiving the electronic component module 3.

[0014] The electronic component module 3 includes the cover 4 and the connector block 5. The cover 4 is a receiving element that has a substantially cuboid shape. The cover 4 is integrally formed from, for example, a synthetic resin. The cover 4 includes a receiving portion 7 therein (see Fig. 5), which contains the substrate 6 (see Fig. 3), which will be described below. The cover 4 includes a front first side wall 41, a rear first side wall 42, a left second side wall 43, a right second side wall 44, and a rear wall 45. The first side walls 41 and 42 and the second side walls 43 and 44 form a tubular portion having a substantially rectangular cross-sectional shape. The rear wall 45 closes one end of the tubular portion formed by the side walls 41, 42, 43, and 44. The other end of the tubular portion is open. In other words, the side walls 41, 42, 43, and 44 and the rear wall 45 form a rectangular tube open at one end thereof.

[0015] The electronic component module 3 of the present embodiment is mounted on the vehicle in a posture in which an axis of the tubular portion formed by the side walls 41, 42, 43, and 44 extends in the up-down direction and an opening of the cover 4 faces downward. In the following description, the "up-down direction" refers to the up-down direction of the vehicle in the state in which the electrical connection box 1 incorporating the electronic component module 3 is mounted on the vehicle. The longer direction of a cross-sectional shape of the cover 4, formed by a plane orthogonal to the up-down direction, is referred to as the "transverse direction," and the shorter direction of the cross-sectional shape is referred to as the "longitudinal direction." The transverse direction is orthogonal to the longitudinal direction.In the present embodiment, the "left side" and the "right side" refer to the left side and the right side when a viewer directly faces the front first side wall 41, which is one of the first side walls 41 and 42. The "front side" and the "rear side" refer to the near side and the far side when the viewer directly faces the front first side wall 41.

[0016] The pair of first side walls 41 and 42 face each other in the longitudinal direction. The pair of second side walls 43 and 44 face each other in the transverse direction. One end of each of the second side walls 43 and 44 in the longitudinal direction is connected to the front first side wall 41, and the other end thereof is connected to the rear first side wall 42. The outer surface of each of the second side walls 43 and 44 is provided with an engaging portion 46. The engaging portion 46 is a projection having a substantially planar U-shape. The frame 2 includes engaging projections corresponding to the engaging portions 46. The engaging portions 46 engage with the engaging projections of the frame 2 to connect the cover 4 to the frame 2.

[0017] As in Fig. 1 and Fig. As illustrated in Fig. 5, the vicinities of the lower ends of the first side walls 41 and 42 are each provided with a plurality of engaging recessed portions 41b and a plurality of engaging recessed portions 42b. The engaging recessed portions 41b and 42b of the present embodiment are through holes penetrating the first side walls 41 and 42, respectively, in the thickness direction thereof. The engaging recessed portions 41b are arranged along the lower side of the front first side wall 41. The engaging recessed portions 42b are arranged along the lower side of the rear first side wall 42. The engaging recessed portions 41b are arranged at intervals, and the engaging recessed portions 42b are arranged at intervals. The first side walls 41 and 42 of the present embodiment are each provided with three such recessed engaging portions 41b and three such recessed engaging portions 42b.One of the three engaging recessed portions 41b and one of the three engaging recessed portions 42b are arranged in the center in the transverse direction, and the other two of the three engaging recessed portions 41b and the other two of the three engaging recessed portions 42b are arranged on one side and on the other side in the transverse direction.

[0018] As in Fig. As illustrated in Figure 2, the frame 2 includes a module receiving portion 2a that receives the electronic component module 3. The frame 2 of the present embodiment includes a plurality of such module receiving portions 2a. The electronic component module 3, which includes the cover 4, is inserted into the module receiving portion 2a and is held by the frame 2.

[0019] The connector block 5 is a block that holds electronic components. The connector block 5 is a block-shaped member that closes the opening of the cover 4. The connector block 5 is integrally formed, for example, from a synthetic resin. An end surface 51 of the connector block 5 is provided with a plurality of connector engagement portions 52. The connector engagement portions 52 are frame-like structural members that protrude from the end surface 51. The connector engagement portions 52 include recesses 52a into which mating connectors fit. A plurality of terminals 53 protrude from the bottoms of the recesses 52a. The terminals 53 are electrically connected to terminals of the mating connectors.

[0020] As in Fig. 3, the connector block 5 supports the substrate 6. The substrate 6 is, for example, a printed circuit board on whose surface wiring of electric circuits is formed. The planar shape of the substrate 6 of the present embodiment is a rectangular shape with corners 6g and 6h chamfered into circular arcs. One end side of the substrate 6 is fixed to fixing portions 56 of the connector block 5 with fixing members such as screws. The fixing portions 56 are provided at both ends in the transverse direction with the terminals 53 interposed therebetween. In the following description, a side of the substrate 6 fixed to the connector block 5 is referred to as a "proximal end side," and a free end side on the opposite side of the side fixed to the connector block 5 is referred to as a "distal end side."The substrate 6 and the connector block 5 are inserted into the cover 4 from a distal end surface 6d.

[0021] The substrate 6 has a plurality of through-holes 6a on the proximal end side. The through-holes 6a penetrate the substrate 6 in the thickness direction thereof. The terminals 53 having conductive properties are inserted into the respective through-holes 6a. Each of the terminals 53 is a rod-like or plate-like member bent at a right angle and inserted at one end thereof from a front side (a front side) of the substrate 6 into a corresponding one of the through-holes 6a. The other ends of the terminals 53 project toward the inside of the recesses 52a of the connector block 5 as described above. The terminals 53 are soldered to be electrically connected to the electrical circuits of the substrate 6.The electronic components such as the resistors 6b and the relays 6c are electrically connected to the electrical circuits of the substrate 6, thereby forming an electrical circuit as a whole.

[0022] The connector block 5 includes projecting engagement portions 54. The projecting engagement portions 54 are projections that correspond to the recessed engagement portions 41b and 42b of the cover 4 (see Fig. 1 and Fig. 5). Each of the protruding engagement portions 54 has an engagement surface 54a. The engagement surface 54a is a plane facing downward, and, for example, a plane orthogonal to the up-down direction. The protruding engagement portions 54 are provided on a front first side surface 5a and a rear first side surface 5b of the connector block 5. The first side surfaces 5a and 5b are side surfaces along the longer direction of the connector block 5, in other words, side surfaces extending in the transverse direction on the connector block 5. Each of the first side surfaces 5a and 5b faces the longitudinal direction. The first side surfaces 5a and 5b are surfaces facing the first inner wall surfaces 41a and 42a of the cover 4.Specifically, the front first side surface 5a faces the front first inner wall surface 41a serving as the inner wall surface of the front first side wall 41, and the rear first side surface 5b faces the rear first inner wall surface 42a serving as the inner wall surface of the rear first side wall 42. The engaging protruding portions 54 project from the first side surfaces 5a and 5b toward the longitudinal directions. The engaging protruding portions 54 are provided on the first side surfaces 5a and 5b as follows: one at the central part of each thereof and one at each of both ends in the transverse direction thereof.

[0023] The protruding engagement portions 54 engage with the recessed engagement portions 41b and 42b to connect the cover 4 to the connector block 5. More specifically, the protruding engagement portions 54 penetrate into the recessed engagement portions 41b and 42b from the inside, that is, from the sides of the first inner wall surfaces 41a and 42a. The engagement surfaces 54a of the protruding engagement portions 54 engage with the recessed engagement portions 41b and 42b to prevent the connector block 5 from detaching from the cover 4.

[0024] A left second side surface 5c and a right second side surface 5d are side surfaces along the shorter direction of the connector block 5, in other words, side surfaces that extend in the longitudinal direction on the connector block 5. Both the left and right second side surfaces 5c and 5d face the transverse direction. The second side surfaces 5c and 5d are surfaces that face the second inner wall surfaces 43a and 44a of the cover 4. More specifically, the left second side surface 5c faces the left second inner wall surface 43a, which serves as the inner wall surface of the left second side wall 43, and the right second side surface 5d faces the right second inner wall surface 44a, which serves as the inner wall surface of the right second side wall 44.

[0025] The second side surfaces 5c and 5d of the connector block 5 are provided with protrusions 55. The protrusions 55 press against the second inner wall surfaces 43a and 44a. As described below, the protrusions 55 press against the second inner wall surfaces 43a and 44a so as to restrict a reduction in the amounts of engagement overlap of the engagement mechanism 9 formed by the engagement protruding portions 54 and the engagement recessed portions 41b and 42b. The protrusions 55 project from the second side surfaces 5c and 5d toward the transverse directions. The protrusions 55 are linear or ridge-shaped protrusions extending in the up-down direction, in other words, along the direction of insertion of the substrate 6.Two such projections 55 (a front projection 55a and a rear projection 55b) are provided on each of the second side surfaces 5c and 5d on the connector block 5 of the present embodiment. The front projection 55a is provided at one end on the front first side surface 5a side of each of the second side surfaces 5c and 5d. The rear projection 55b is provided at one end on the rear first side surface 5b side of each of the second side surfaces 5c and 5d. That is, the projections 55 are located at ends on the first side surfaces 5a and 5b sides of the second side surfaces 5c and 5d.

[0026] The shape of the connector block 5 is described with reference to Fig. 4 described in more detail. As in Fig. As illustrated in Fig. 4, the shape (the planar shape) of the connector block 5 is substantially rectangular when viewed from above. The rear first side surface 5b protrudes slightly more at the central part than at both ends thereof toward the longitudinal direction. More specifically, the rear first side surface 5b includes a central part 5b1 and inclined parts 5b2 and 5b3. Grooves 5b4 and 5b5 extending in the up-down direction are provided between the central part 5b1 and the inclined parts 5b2 and 5b3. The central part 5b1 is a central part in the transverse direction at the rear first side surface 5b. The inclined part 5b2 is a part on the left side of the central part 5b1, and the inclined part 5b3 is a part on the right side of the central part 5b1. The central part 5b1 is a surface parallel to the front first side surface 5a.Each of the inclined portions 5b2 and 5b3 is inclined so as to approach the front first side surface 5a with increasing distance from the central portion 5b1 in the transverse direction. Ends of the inclined portions 5b2 and 5b3 on the side of the central portion 5b are located at substantially the same positions in the longitudinal direction as the central portion 5b1. According to the shape of the rear first side surface 5b, the rear first side wall 42 protrudes slightly more toward the longitudinal direction at the central portion than at both ends thereof.

[0027] Of the two protrusions 55 provided on each of the second side surfaces 5c and 5d, the rear protrusion 55b is located at one end on the rear first side surface 5b side. More specifically, the rear protrusion 55b is located adjacent to a circular arc portion 5e located at a part where each of the second side surfaces 5c and 5d intersects the rear first side surface 5b. The front protrusion 55a is located at one end on the front first side surface 5a side. More specifically, the connector block 5 includes an inclined surface 5f connecting the front first side surface 5a to each of the second side surfaces 5c and 5d. The inclined surface 5f is a surface inclined with respect to the front first side surface 5a and each of the second side surfaces 5c and 5d.The front projection 55a is arranged adjacent to a corner at which the inclined surface 5f intersects each of the second side surfaces 5c and 5d.

[0028] With reference back to Fig. 3, the projections 55 are provided on the lower end side of the connector block 5. More specifically, the projections 55 extend upward in predetermined areas from flange portions 57. The flange portions 57 are flange-like projections that protrude from the lower ends of the second side surfaces 5c and 5d toward the transverse direction. The flange portions 57 serve as stoppers that abut against one end on the opening side of the cover 4.

[0029] As in Fig. 5, the cover 4 includes a receiving portion 7. The receiving portion 7 is a space surrounded by the first side walls 41 and 42, the second side walls 43 and 44, and the rear wall 45. In other words, the receiving portion 7 is an inner space of the cover 4, which has a bottomed tubular shape. Each of the second side walls 43 and 44 of the cover 4 includes a first guide portion 47, a second guide portion 48, and a projection 49. The guide portions 47 and 48 and the projection 49 are provided on each of the second inner wall surfaces 43a and 44a of the second side walls 43 and 44. The second inner wall surfaces 43a and 44a are surfaces facing side surfaces 6e and 6f of the substrate 6 (see Fig. 3). The first and second guide portions 47 and 48 extend in the up-down direction, in other words, along the depth direction of the receiving portion 7. The first and second guide portions 47 and 48 face each other in the longitudinal direction. The first and second guide portions 47 and 48 are integrally formed with each of the second side walls 43 and 44.

[0030] A groove 8 is provided between the first guide portion 47 and the second guide portion 48. The first and second guide portions 47 and 48 guide the substrate 6, which is inserted into the receiving portion 7, to the groove 8. The projection 49 is a projecting portion projecting from each of the second inner wall surfaces 43a and 44a and is formed integrally with each of the second side walls 43 and 44. The shape of the projection 49 of the present embodiment is a triangular-prismatic shape and extends in the longitudinal direction. Both ends of the projection 49 are connected to the first and second guide portions 47 and 48, respectively. The distance between the distal end of the projection 49 of the left second side wall 43 and the distal end of the projection 49 of the right second side wall 44 is smaller than a width W1 of the substrate 6 (see Fig. 3). The projection 49 is a crushable rib that is plastically deformed by contacting the substrate 6 inserted into the receiving portion 7.

[0031] The substrate 6 is inserted from an opening 4a of the cover 4 toward the rear wall 45. More specifically, the connector block 5 and the substrate 6 are inserted into the receiving portion 7 from the opening 4a toward the rear wall 45, with the distal end surface 6d of the substrate 6 serving as the front end. The receiving portion 7 of the cover 4 receives the inserted substrate 6 therein and accommodates at least a part of the connector block 5. The connector block 5, inserted into the receiving portion 7, closes the opening 4a of the cover 4, so that a closed space is formed in the cover 4 to accommodate the substrate 6.

[0032] When the connector block 5 is inserted into the receiving section 7 as shown in Fig. As illustrated in Figure 1, the protruding engagement portions 54 of the connector block 5 penetrate into the recessed engagement portions 41b and 42b from the inside of the cover 4 and engage with the recessed engagement portions 41b and 42b. The protruding engagement portions 54, which engage with the recessed engagement portions 41b and 42b, prevent the connector block 5 from disengaging from the receiving portion 7. The cover 4 covers the connector block 5, the substrate 6, and the electronic components such as the resistors 6b and the relays 6c in an integrated manner.

[0033] When the substrate 6 inserted into the receiving portion 7 abuts against the protrusions 49, parts of the protrusions 49 abutting against the substrate 6 are plastically deformed. The material (strength), shape, dimensions, and the like of the protrusion 49 are set so that at least a part on the distal end side thereof is plastically deformed so that it is crushed upon contact with the substrate 6. The material (elastic modulus), shape, dimensions, and the like of the protrusion 49 are desirably set so that at least a part on the proximal end side thereof can be elastically deformed so that the contact state between the protrusion 49 and the substrate 6 is maintained.Upon completion of insertion of the substrate 6 into the receiving portion 7, a groove is formed on the protrusion 49 by plastic deformation so that the substrate 6 is clamped from both sides thereof in the longitudinal direction. Although the groove of the protrusion 49 desirably holds the substrate 6 by contacting the substrate 6, in some cases, a gap may be present between the protrusion 49 and the substrate 6.

[0034] The projections 49 restrict a displacement of the substrate 6 relative to the cover 4. As in Fig. As illustrated in Figure 6, the pair of projections 49, which oppose each other in the transverse direction, restricts the displacement of the substrate 6 relative to the cover 4 in the transverse direction. The projection 49 of the left second side wall 43a reduces the range of movement of the substrate 6 toward the left second inner wall surface 43a. The projection 49 of the right second side wall 44a reduces the range of movement of the substrate 6 toward the right second inner wall surface 44a. In this way, the pair of projections 49 restricts the displacement of the substrate 6 relative to the cover 4 in the transverse direction.

[0035] The grooves formed by plastic deformation on the protrusions 49 clamp the substrate 6 from both sides in the longitudinal direction, thereby restricting the displacement of the substrate 6 relative to the cover 4 in the longitudinal direction. Thus, the protrusions 49 of the present embodiment prevent the cover 4 and the substrate 6 from moving independently of each other when the vehicle vibrates; in other words, they prevent separate, independent vibrations from occurring between the cover 4 and the substrate 6.

[0036] As in Fig. As illustrated in Fig. 6, the projections 55 come into contact with the second inner wall surfaces 43a and 44a of the cover 4 and press against the second inner wall surfaces 43a and 44a. The projections 55 are arranged so that they are capable of coming into contact with and pressing against the second inner wall surfaces 43a and 44a at least in the state where the engagement mechanism 9 is engaged. The projection amounts of the projections 55 are set so that the projections 55 on the left second side surface 5c press against the left second inner wall surface 43a, and the projections 55 on the right second side surface 5d press against the right second inner wall surface 44a.In other words, the projections 55 are designed so that the connector block 5 is pressed into the cover 4 in the state where the projections 55 on the left second side surface 5c are in contact with the left second inner wall surface 43a and the projections 55 on the right second side surface 5d are in contact with the right second inner wall surface 44a.

[0037] The projections 55 press against the second inner wall surfaces 43a and 44a so as to prevent the first side surfaces 5a and 5b and the first inner wall surfaces 41a and 42a from moving relatively in diverging directions. For example, as shown in Fig. 7, compressive forces F1 acting from the projections 55 on the second inner wall surfaces 43a and 44a deform the cover 4. In Fig. 7, dashed lines represent the shape of the cover 4 before it is deformed, and the solid lines represent the shape of the cover 4 after it has been deformed. As in Fig. 7, the cover 4 is deformed so that the first inner wall surfaces 41a and 42a approach the first side surfaces 5a and 5b. More specifically, the cover 4 is deformed inward so that a deformation amount u increases from both ends toward the central part in the transverse direction of the first side walls 41 and 42. Since the deformation amount u is larger at the central part as described above, it is desirable that at least one of the engaging projecting portions 54 be provided at the central part in the transverse direction of each of the first side surfaces 5a and 5b, and at least one of the engaging recessed portions 41b and 42b corresponding to the provided engaging projecting portion 54 be provided at the central part of each of the first side walls 41 and 42.

[0038] The projections 55 deform the cover 4 to increase the engagement overlap amounts of the engagement mechanism 9 formed by the engagement projection portions 54 and the engagement recessed portions 41b and 42b. The term "engagement overlap amounts" refers to lengths of overlap in the longitudinal direction between the engagement projection portions 54 and the engagement recessed portions 41b and 42b. By increasing the engagement overlap amounts, accidental disengagement of the engagement mechanism 9 is prevented. For example, the engagement projection portions 54 are prevented from disengaging from the engagement recessed portions 41b and 42b due to vibration or impact.

[0039] The compressive forces F1 from the protrusions 55 exert stresses F2 on the first side walls 41 and 42. The stresses F2 prevent the first side walls 41 and 42 from deforming in the longitudinal directions. That is, the stresses F2 prevent the first side surfaces 5a and 5b and the first inner wall surfaces 41a and 42a from moving relatively in diverging directions. The protrusions 55 prevent the first side walls 41 and 42 from deforming in a direction in which the amounts of engagement overlap of the engagement mechanism 9 are reduced, thus improving the stability of the engagement state of the engagement mechanism 9. Consequently, the protrusions 55 of the present embodiment can improve the reliability of the engagement mechanism 9 by preventing the inadvertent release of the engagement state of the engagement mechanism 9.

[0040] In the present embodiment, the protrusions 55 are located at the ends on the sides of the first side surfaces 5a and 5b on the second side surfaces 5c and 5d. Disposing the protrusions 55 at the ends of the second side surfaces 5c and 5d reduces the protrusion amounts of the protrusions 55 required to generate the same amount of deformation of the first side walls 41 and 42. Disposing the protrusions 55 at the ends of the second side surfaces 5c and 5d further reduces the protrusion amounts of the protrusions 55 required to generate the same amount of stress F2.

[0041] As mentioned with reference to Fig. 8 and Fig. 9, the frame 2 of the present embodiment includes frame-side protrusions 21 that prevent displacement of the cover 4 relative to the frame 2. The frame-side protrusions 21 are provided on wall surfaces in the frame 2 that face the cover 4. The frame-side protrusions 21 of the present embodiment are provided on the wall surfaces in the frame 2 that face the respective second side walls 43 and 44. In other words, the frame-side protrusions 21 are provided on the wall surfaces that face each other in the transverse direction with the cover 4 interposed therebetween. Fig. 8 and Fig. 9 illustrate a wall surface 22 in the frame 2 facing the right second side wall 44, and further illustrate the frame-side projections 21 provided on the wall surface 22. The frame-side projections 21 provided on a wall surface facing the left second side wall 43 are the same as the frame-side projections 21 provided on the wall surface 22.

[0042] The frame-side projections 21 project from the wall surface 22 to the interior of the module receiving portion 2a. In the frame 2 of the present embodiment, a pair of ribs 23 and 23 project from the wall surface 22, as shown in Fig. 8. The rib 23 is a projection having a rectangular cross-sectional shape and extending in the up-down direction. For example, an engaging projection for engaging with the engaging portion 46 of the cover 4 (see Fig. 1) between the pair of ribs 23 and 23. Each of the frame-side projections 21 is provided on the distal end surface of the rib 23. As shown in Fig. 9, the frame-side projection 21 is provided in a predetermined range upward from the lower end of the module receiving portion 2a. The cross-sectional shape of the frame-side projection 21 is a tapered shape having a width in the longitudinal direction decreasing toward the distal end side in the projecting direction of the frame-side projection 21.

[0043] The frame-side protrusion 21 is a crushable rib that is plastically deformed by coming into contact with the cover 4 inserted into the module receiving portion 2a. When the cover 4 inserted into the module receiving portion 2a comes into contact with the frame-side protrusion 21, a portion of the frame-side protrusion 21 that is in contact with the cover 4 is plastically deformed. The cover 4 is inserted into the module receiving portion 2a from, for example, below it with the rear wall 45 facing upward. The outer wall surfaces of the second side walls 43 and 44 of the cover 4 are located further outward laterally at portions on the rear end side (the opening 4a side) thereof than at portions on the front end side (the rear wall 45 side) thereof in the insertion direction.That is, on the outer wall surfaces of the cover 4, portions facing the frame-side protrusions 21 when inserted into the module receiving portion 2a are expanded more toward the transverse direction on the rear end side than on the front end side. The front end portions of the cover 4 can be inserted into the module receiving portion 2a without coming into contact with the frame-side protrusions 21. On the other hand, the rear end portions of the cover 4 come into contact with the frame-side protrusions 21 to plastically deform the frame-side protrusions 21. The cover 4 is inserted into the module receiving portion 2a until the engaging protrusions of the frame 2 engage with the engaging portions 46 while plastically deforming the frame-side protrusions 21.The cover 4 is held by the frame-side projections 21 in the state in which it is received in the module receiving portion 2a. The frame-side projections 21 restrict the displacement of the cover 4 relative to the frame 2 in the transverse direction. The frame-side projections 21 can also restrict the displacement of the cover 4 relative to the frame 2 in the longitudinal direction.

[0044] In this way, in the electrical connection box 1 of the present embodiment, the second side walls 43 and 44 of the cover 4 are held by both surfaces thereof by the projections 55 and the frame-side projections 21. This reduces both the rattling of the cover 4 and the substrate 6 against the frame 2 and the rattling of the substrate 6 against the cover 4. This, in turn, can reduce the influence of vibrations on the electronic components and soldered parts of the substrate 6 in the electrical connection box 1 of the present embodiment. In the present embodiment, as shown in Fig. As illustrated in Figure 8, the projections 55 face the frame-side projections 21 in the transverse direction with the second side walls 43 and 44 interposed therebetween. This appropriately reduces rattling of the cover 4. Although the projections 55 preferably coincide in positions in the longitudinal direction with the frame-side projections 21, the positions may slightly mismatch in the longitudinal direction, as illustrated in the present embodiment.

[0045] As described above, the engagement structure 100 of the present embodiment includes the connector block 5, the cover 4, the engagement mechanism 9, and the protrusions 55. The connector block 5 includes the first side surfaces 5a and 5b and the second side surfaces 5c and 5d, and holds the electronic components such as the resistors 6b and the relays 6c through the substrate 6. The cover 4 includes the first inner wall surfaces 41a and 42a facing the first side surfaces 5a and 5b, and the second inner wall surfaces 43a and 44a facing the second side surfaces 5c and 5b. The cover 4 covers the connector block 5 and the electronic components such as the resistors 6b and the relays 6c in an integrated manner.

[0046] The engagement mechanism 9 includes the protruding engagement portions 54 provided on the first side surfaces 5a and 5b, and the recessed engagement portions 41b and 42b provided in the first inner wall surfaces 41a and 42a. The first side surfaces 5a and 5b approach and move away from the first inner wall surfaces 41a and 42a so that the engagement mechanism 9 engages and disengages. The projections 55 are provided on the second side surfaces 5c and 5d. In the engaged state of the engagement mechanism 9, the projections 55 contact the second inner wall surfaces 43a and 44a and press against the second inner wall surfaces 43a and 44a, preventing the first side surfaces 5a and 5b and the first inner wall surfaces 41a and 42a from moving relatively in diverging directions.The engagement structure 100 according to the present embodiment restricts the relative movement of the first inner wall surfaces 41a and 42a in the direction separating them from the first side surfaces 5a and 5b, so that it is capable of preventing accidental disengagement of the engagement mechanism 9 caused by vibration, shock, or the like. As a result, the engagement structure 100 can improve the reliability of the engagement mechanism 9.

[0047] The projections 55 press against the second inner wall surfaces 43a and 44a to deform the cover 4 so that the first side surfaces 5a and 5b approach the first inner wall surfaces 41a and 42a. In other words, the projections 55 deform the cover 4 with the compressive forces F1 by pressing against the second inner wall surfaces 43a and 44a to increase the amounts of engagement overlap of the engagement mechanism 9. The projections 55 appropriately prevent the inadvertent disengagement of the engagement mechanism 9, thereby improving the reliability of the engagement mechanism 9.

[0048] In the engagement structure 100 of the present embodiment, the second side surfaces 5c and 5d are surfaces that intersect the first side surfaces 5a and 5b, and the protrusions 55 are located at the ends on the sides of the first side surfaces 5a and 5b on the second side surfaces 5c and 5d. The protrusions 55 provided adjacent to the first side surfaces 5a and 5b can facilitate such deformation of the cover 4 as to increase the amounts of engagement overlap of the engagement mechanism 9. The protrusions 55 provided adjacent to the first side surfaces 5a and 5b generate the appropriate stresses in the second side walls 43 and 44 so as to be able to restrict the deformation of the second side walls 43 and 44 in the direction in which the amounts of engagement overlap of the engagement mechanism 9 are reduced.

[0049] The electronic component module 3 of the present embodiment includes, in addition to the electronic components, the connector block 5, the cover 4, the engagement mechanism 9, and the projections 55 according to the engagement structure 100 described above. The electronic component module 3 of the present embodiment can improve the reliability of the engagement mechanism 9 by incorporating the engagement structure 100 described above.

[0050] The electrical junction box 1 of the present embodiment includes the electronic component module 3 described above and the frame 2 that holds the electronic component module 3 therein. The electrical junction box 1 of the present embodiment can improve the reliability of the engagement mechanism 9 by incorporating the engagement structure 100 described above. Modification of the embodiment

[0051] The number of protrusions 55 provided on the second side surfaces 5c and 5d is not limited to the number exemplified above. For example, one such protrusion 55 may be provided on each of the second side surfaces 5c and 5d. In this case, the protrusion 55 is desirably arranged at the central part in the longitudinal direction of each of the second side surfaces 5c and 5d. The shape of the protrusion 55 is not limited to the shape exemplified above. The planar shape of the protrusion 55 may be, for example, a dot shape instead of the line shape or the ridge shape. The width of the protrusion 55 may be larger than the width illustrated in the drawings. The protrusion 55 may extend in a horizontal direction instead of the up-down direction. The protrusion 55 may be provided on only one of the second side surfaces 5c and 5d.

[0052] In the above-described embodiment, the side surfaces in the longer direction of the connector block 5 serve as first side surfaces 5a and 5b, and the side surfaces in the shorter direction of the connector block 5 serve as second side surfaces 5c and 5d. Conversely, however, the side surfaces in the shorter direction may serve as first side surfaces 5a and 5b, and the side surfaces in the longer direction may serve as second side surfaces 5c and 5d.

[0053] Although the shape of the connector block 5 in the above-described embodiment is substantially rectangular in plan view, the shape is not limited thereto. The planar shape of the connector block 5 may be a polygonal shape other than the rectangular shape or a shape based on the polygonal shape. The first side surfaces 5a and 5b do not need to be adjacent to the second side surfaces 5c and 5d. The first side surfaces 5a and 5b desirably intersect the second side surfaces 5c and 5d, but do not need to be orthogonal to them.

[0054] The first side surface and the second side surface may be provided on different sides (back to back), with the main part of the connector block 5 arranged therebetween. For example, on the connector block 5 of the embodiment described above (see Fig. 3 and Fig.4) The surface referred to as the front first side surface 5a serves as the second side surface. The second side surface (the surface referred to as the front first side surface 5a) is provided with the projections 55 instead of the engaging projecting portions 54. In this way, the surface referred to as the front first inner wall surface 41a in the above-described embodiment serves as the second inner wall surface. The projections 55 press against the second inner wall surface (the surface referred to as the front first inner wall surface 41a) of the cover 4. This pressing force is a force in one direction, causing the rear first side surface 5b and the rear first inner wall surface 42a to come close to each other. As a result, the projections 55 prevent the first side surface and the first inner wall surface from moving relatively in diverging directions.

[0055] In the above-described embodiment, the first side surfaces 5a and 5b are provided with the protruding engagement portions 54, and the first side walls 41 and 42 are provided with the recessed engagement portions 41b and 42b. However, instead, the first side walls 41 and 42 may be provided with protruding engagement portions, and the first side surfaces 5a and 5b may be provided with recessed engagement portions. The projections 55 may be provided on the second inner wall surfaces 43a and 44a instead of the second side surfaces 5c and 5d.

[0056] The contents disclosed in the embodiment and its modification described above may be implemented in appropriate combinations thereof.

[0057] An engagement structure, an electronic component module, and an electrical connection box according to the embodiment each include a block having a first side surface and a second side surface and holding an electronic component; a cover having a first inner wall surface facing the first side surface and a second inner wall surface facing the second side surface, and integrally covering the block and the electronic component; an engagement mechanism including a protruding engagement portion provided on one of the first side surface and the first inner wall surface, and a depressed engagement portion provided on the other of the first side surface and the first inner wall surface;and a protrusion provided on one surface of the second side surface and the second inner wall surface, which is configured to contact the other surface of the second side surface and the second inner wall surface so as to press against the other surface so that the first side surface and the first inner wall surface are prevented from relatively moving in directions diverging from each other in an engaged state of the engagement mechanism. The engagement structure, the electronic component module, and the electrical connection box according to the embodiment provide the effect that the protrusion prevents the first side surface and the first inner wall surface from relatively moving in directions diverging from each other, so that the reliability of the engagement structure can be improved.

Claims

[1] Electrical connection box (1) comprising: an electronic component (6b, 6c); a block (5) having a first side surface (5a, 5b) and a second side surface (5c, 5d) and holding the electronic component (6b, 6c); a cover (4) having a first inner wall surface (41a, 42a) facing the first side surface (5a, 5b) and a second inner wall surface (43a, 44a) facing the second side surface (5c, 5d), and covering the block (5) and the electronic component (6b, 6c) in an integrated manner; an engagement mechanism (9) including a projecting engagement portion (54) provided on one of the first side surface (5a, 5b) and the first inner wall surface (41a, 42a) and a recessed engagement portion (41b, 42b) provided on the other of the first side surface (5a, 5b) and the first inner wall surface (41a, 42a); a projection (55) provided on one surface of the second side surface (5c, 5d) and the second inner wall surface (43a, 44a) and configured to contact the other surface of the second side surface (5c, 5d) and the second inner wall surface (43a, 44a) so as to press against the other surface and deform the cover (4) inwardly so that the first side surface (5a, 5b) and the first inner wall surface (41a, 42a) approach each other and a deformation amount (u) increases from both ends toward a central part in the transverse direction of the first inner wall surface (41a, 42a), thereby preventing the first side surface (5a, 5b) and the first inner wall surface (41a, 42a) from relatively moving in directions diverging from each other in an engaged state of the engagement mechanism (9); and a frame holding an electronic component module (3) therein, which includes the electronic component (6b, 6c), the block (5) and the cover (4).

Images