JP2011066148A - Storage case with board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage case with a board having a novel structure such that while solder cracking is suppressed, the printed board can be securely positioned and held in the storage case. <P>SOLUTION: Through an engaging operation between a pair of positioning protrusions 30, 30 positioned in one diagonal direction of the storage case 12 and a notched engagement part 48 of the printed board 14, displacement of the printed board 14 in the one diagonal direction is restricted, and a notched screwing part 50 of the printed board 14 is held non-fixedly between a pair of mounting screws 54, 54 positioned in the other diagonal direction of the storage case 12 and board support surfaces 40, 40 supporting the printed board 14 to restrict displacement of the printed board 14 in the other diagonal direction and displacement in a direction of flotation over the storage case 12. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a housing case with a substrate to which a printed circuit board is assembled.

  Conventionally, a housing case with a substrate in which a printed circuit board with a specific circuit pattern formed on a surface is assembled to a synthetic resin housing case as a component of an electric circuit that is used by being connected to an automobile wire harness, etc. ing. For example, it is as described in Patent Document 1 (Japanese Utility Model Laid-Open No. 5-50789).

  By the way, as described in Patent Document 1, in the case with a substrate having a conventional structure, a plurality of locations on the outer peripheral edge of the printed circuit board are fastened with mounting screws and fixed to the case. That is, as shown in FIG. 1 of Patent Document 1, the printed circuit board is fixed to the housing case by holding the edge portion of the printed circuit board between the mounting screw head and the board support portion of the housing case. It was attached.

  However, the printed circuit board tends to warp particularly at the edge portion when the molding accuracy is poor, and there is a possibility that an excessive load is applied to the printed circuit board when the bolt is forcibly tightened. Furthermore, since the printed circuit board is firmly fixed to the housing case, the printed circuit board is pulled by deformation of the housing case due to the heat of the circuit when mounted on the vehicle, and warping, etc., and the connection terminals and electrical components are soldered. There is a problem that stress is concentrated on the soldered portion, and solder cracks cannot be avoided. In addition, due to the difference in linear expansion coefficient between the printed circuit board and the housing case due to heating when soldering the connection terminals or the like, there is a possibility that stress concentrates on the soldering portion and solder cracks occur.

Japanese Utility Model Publication No. 5-50789

  The present invention has been made in the background of the above-described circumstances, and the solution is to provide a substrate with a novel structure that can reliably hold the printed circuit board with respect to the housing case while suppressing the occurrence of solder cracks. It is to provide a storage case.

  The first aspect of the present invention is a housing case with a substrate in which a rectangular plate-like printed circuit board is overlaid and assembled to a synthetic resin housing case, and on the overlapping surface of the printed circuit board in the housing case, Positioning support portions are respectively formed in portions corresponding to the squares of the printed circuit board, and each of the positioning support portions is provided with a substrate support surface on which the square portion of the printed circuit board is placed and supported. A pair of positioning support portions positioned in one diagonal direction are provided with positioning protrusions positioned outward from the substrate support surface, and a corresponding pair of corner portions of the printed circuit board. Each of the printed circuit boards has a notch-like engaging portion formed by engaging each positioning portion with the positioning protrusion. While the displacement in the diagonal direction is restricted, a pair of positioning support portions positioned in another diagonal direction are screwed to the outer side of the substrate support surface, and mounting screws are screwed thereto, A pair of corner portions of the corresponding printed circuit board are formed with notch-shaped screwing portions, respectively, and are not fixed between the board support surface of each screwing portion and the head of the mounting screw. The holding action restricts the displacement in the other diagonal direction of the printed circuit board and the displacement in the lifting direction from the substrate support surface.

  According to the present invention, by positioning the printed circuit board at the square portion, the rectangular flat plate-shaped printed circuit board can be easily positioned with high accuracy and set at a predetermined position. That is, although it is difficult to obtain accuracy by positioning at the side portion of the printed circuit board, positioning can be performed accurately and easily by positioning at the square portion.

  In addition, in the pair of corners in one diagonal direction, the positioning of the printed circuit board in the surface direction on the assembly surface of the housing case can be easily and efficiently performed by the engaging portion and the positioning protrusion. . With the substrate set at a predetermined position by such positioning, it becomes easy to attach the mounting screws at a pair of corners in another diagonal direction. Since these mounting screws also regulate the displacement of the substrate in another diagonal direction, cooperation between the engaging portion and the positioning projection and the pinching operation of the screwing portion and the mounting screw. Based on the action, the printed circuit board can be efficiently positioned on the assembly surface of the housing case as a whole. Also, under this positioning state, the board screwing portion is held between the head of the mounting screw and the board support surface, so that the board can be removed in the direction away from the mounting surface of the housing case. Can be prevented.

  In particular, in the above-described board assembly state, the board screwing portion is prevented from being detached between the head of the mounting screw and the board support surface, and the displacement in the plane direction is allowed in a non-fixed state. Is retained. This makes it possible to reduce or avoid as much as possible the external force exerted on the printed circuit board due to the difference in thermal expansion between the housing case and the printed circuit board, for example, when heating the circuit in the vehicle or when heating during soldering. It becomes. Even when the printed circuit board is warped, the external force applied at the time of screw tightening can be reduced or avoided. Therefore, it is possible to effectively prevent the occurrence of solder cracks.

  According to a second aspect of the present invention, in the one described in the first aspect, a distance between opposing surfaces of the substrate support surface and the head of the mounting screw is made larger than a thickness dimension of the screwing portion. It is what.

  According to this aspect, since the screwing portion of the printed board is held with a clearance between the board support surface and the mounting screw head, the action of external force on the printed board can be avoided more reliably, and solder cracks can be prevented. Prevention is achieved more effectively.

  According to a third aspect of the present invention, in the first or second aspect, a connection terminal that is soldered to the printed circuit board protrudes from the housing case.

  If it does in this way, while the terminal of the connector connection part in a storage case is comprised with a connection terminal, this connection terminal can be connected to a printed circuit board. Since the printed circuit board can be easily and accurately positioned in the housing case by the structure according to the present invention, the connection terminal can be easily and accurately positioned with respect to the printed circuit board. Furthermore, since the printed circuit board is held in a non-fixed manner in the storage case, it is possible to reduce or avoid the follow-up of the printed circuit board to the deformation of the storage case due to the heat of soldering. Can be reduced.

  According to a fourth aspect of the present invention, in the above-described third aspect, in the housing case, the protruding height of the positioning protrusion from the substrate support surface is from the substrate support surface of the connection terminal. It is larger than the protruding height.

  In this way, the printed circuit board can be reliably positioned with respect to the housing case before the connection terminal is inserted into the through hole of the printed circuit board. This can be avoided, and the insertion work is facilitated.

  According to the present invention, the displacement in one diagonal direction of the printed circuit board is regulated by the engaging action of the pair of positioning protrusions positioned in the one diagonal direction of the housing case and the notch-shaped engaging part of the printed circuit board. At the same time, the notched screwing portion of the printed circuit board is non-fixedly held between the pair of mounting screws located in the other diagonal direction of the housing case and the board support surface that supports the printed circuit board. The displacement of the substrate in another diagonal direction and the displacement in the lifting direction with respect to the housing case were regulated. As a result, the printed circuit board can be accurately positioned and held with respect to the housing case. Furthermore, by holding the printed circuit board non-fixed between the mounting screw and the printed circuit board support surface, the printed circuit board can be printed due to the difference in thermal expansion between the housing case and the printed circuit board due to the heat of the circuit in the vehicle and the heat during soldering. The external force exerted on the substrate can be reduced and the occurrence of solder cracks can be suppressed.

The disassembled perspective view of the storage case with a board | substrate as one Embodiment of this invention. The perspective view which shows one positioning support part of the storage case shown in FIG. The perspective view which shows the other positioning support part of the storage case shown in FIG. The top view which shows the assembly | attachment state of the printed circuit board to the positioning support part shown in FIG. The top view which shows the assembly | attachment state of the printed circuit board to the positioning support part shown in FIG. Explanatory drawing equivalent to the VI-VI cross section in FIG.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, FIG. 1 shows a storage case 10 with a substrate as one embodiment of the present invention. The accommodation case 10 with a substrate has a structure in which a printed circuit board 14 is overlaid and assembled to an accommodation case 12 made of synthetic resin.

  The housing case 12 is made of a non-conductive synthetic resin and has a substantially rectangular box shape with a long side opening upward (in FIG. 1). A concave housing portion 16 that is recessed in the opposite direction to the opening direction is integrally formed at the central portion of the housing case 12, and a connector housing portion 18 is integrally formed on the side surface of the concave housing portion 16. A plurality of linear connection terminals 20 are provided through the connector housing portion 18, and one end of the connection terminal 20 is exposed outside the housing case 12 in the connector housing portion 18. At the same time, a portion of the connection terminal 20 that protrudes from the connector housing portion 18 into the concave housing portion 16 is bent in the opening direction of the housing case 12, so that the other end portion of the connection terminal 20 opens in the opening direction of the housing case 12. Projected to

  Further, in the housing case 12, an overlapping surface 22 that extends outward from the concave housing portion 16 over the entire circumference is integrally formed at the opening edge of the concave housing portion 16. The overlapping surface 22 has a substantially rectangular outer shape with a size corresponding to the printed circuit board 14, and the printed circuit board 14 is superimposed on the overlapping surface 22. A pair of positioning support portions 24a and a pair of positioning support portions 24b are respectively formed on portions of the overlapping surface 22 corresponding to the squares of the printed circuit board 14. A pair of positioning support portions 24a, 24a having the same structure is positioned in one diagonal direction of the overlapping surface 22, while a pair of positioning support portions 24b, 24b having the same structure is used. Is positioned in the other diagonal direction of the overlapping surface 22.

  FIG. 2 shows the positioning support portion 24a. A substrate support surface 26 is integrally formed on the positioning support portion 24 a so as to protrude from the overlapping surface 22 in the opening direction of the housing case 12 and to extend parallel to the overlapping surface 22. The substrate supporting surface 26 is a substantially L-shaped flat surface having a predetermined width dimension and a substantially arcuate portion having a substantially ¼ circumference inside the corner portion of the overlapping surface 22. The protruding height position of the substrate support surface 26 from the overlapping surface 22 is slightly smaller than the protruding height dimension of the outer peripheral wall 28 formed on the outer peripheral edge of the overlapping surface 22 from the overlapping surface 22. Specifically, it is positioned closer to the overlapping surface 22 than the outer peripheral wall 28 by an amount substantially equal to or slightly larger than the thickness dimension of the printed circuit board 14.

  Further, the positioning protrusions 30 are integrally formed on the positioning support portion 24 a so as to be positioned outward of the substrate support surface 26 in the diagonal direction of the overlapping surface 22 at the corners of the housing case 12. The positioning protrusion 30 is a protrusion protruding from the substrate support surface 26 in the opening direction of the housing case 12. The protrusion height dimension h1 of the positioning protrusion 30 from the substrate support surface 26 is larger than that of the outer peripheral wall 28, and preferably from the protrusion height of the connection terminal 20 protruding from the housing case 12 from the substrate support surface 26. In this embodiment, the height is slightly larger than the protruding height of the connection terminal 20.

  In addition, the inner side surface 32 located inside the housing case 12 in the positioning protrusion 30 has an arcuate surface 34 of approximately ¼ circumference along the substrate support surface 26. Furthermore, a tapered guide surface 36 whose cross-sectional area gradually increases as it approaches the overlapping surface 22 is formed on the projecting tip portion side of the inner side surface 32.

  On the other hand, FIG. 3 shows the positioning support 24b. A screw hole 38 extending in the opening direction of the housing case 12 is formed in the central portion of the positioning support portion 24b. A substrate support surface 40 is formed around the screw hole 38 and inside the screw hole 38 with respect to the diagonal direction of the housing case 12. The substrate support surface 40 is formed at substantially the same height as the substrate support surface 26 provided in the positioning support portion 24 a with respect to the overlapping surface 22. Further, the substrate support surface 40 is a flat surface having a predetermined width dimension and extending substantially ¼ around the screw hole 38 inside the corner portion of the overlapping surface 22.

  A locking projection 42 is formed around the screw hole 38 over substantially 3/4 of the circumference, excluding the substrate support surface 40. The locking protrusion 42 is a protrusion that protrudes from the substrate support surface 40 in the opening direction of the housing case 12, and the protruding end surface 44 is a flat surface. The protrusion height dimension h2 of the locking protrusion 42 from the board support surface 40 is set to be equal to or greater than the thickness dimension t of a screwing part 50 described later on the printed circuit board 14. The thickness dimension of the stopper 50 is slightly larger than t.

  As shown in FIG. 1, a substantially semicircular substrate support surface 46 that protrudes inward is formed at the longitudinal center of the outer peripheral wall 28 on the long side of the housing case 12. The protruding height dimension of the substrate support surface 46 from the overlapping surface 22 is equal to the substrate support surfaces 26 and 40 of the positioning support portions 24a and 24b.

  On the other hand, the printed circuit board 14 has substantially the same structure as a conventionally known printed circuit board, and has a long, substantially rectangular plate shape corresponding to the overlapping surface 22. In the printed circuit board 14, the two corners corresponding to the positioning support portion 24 b are formed in the two corners corresponding to the positioning support portion 24 b while the two corner portions corresponding to the positioning support portion 24 a are overlapped with the overlapping surface 22. A screwing portion 50 is formed on the portion. The engaging portion 48 has an arcuate cutout shape of approximately ¼ circumference along the arcuate surface 34 in the positioning support portion 24a. On the other hand, the screwing portion 50 has an arcuate cutout shape of approximately ¼ circumference along the screw hole 38 in the positioning support portion 24b. Further, a through hole 52 through which the connection terminal 20 is inserted at a position corresponding to each of the connection terminals 20 projecting from the housing case 12 in a state of being superimposed on the overlap surface 22 in a substantially central portion of the printed circuit board 14. Are penetrated in the thickness direction.

  Then, the printed circuit board 14 is superimposed on the overlapping surface 22 of the storage case 12 from the opening direction of the storage case 12. Since the positioning protrusion 30 of the positioning support portion 24a protrudes larger than the connection terminal 20 when the printed circuit boards 14 are overlapped, the positioning support portion is inserted before the connection terminal 20 is inserted into the through hole 52. The engagement between the engaging portion 48 formed at the corner corresponding to 24a and the positioning protrusion 30 is started. Further, the printed circuit board 14 is guided to a predetermined position with respect to the overlapping surface 22 by the guide surface 36 of the positioning protrusion 30.

  Then, as shown in FIG. 4, a pair of corners in one diagonal direction of the printed circuit board 14 is placed and supported on the board support surface 26 of the positioning support part 24a, and as shown in FIG. A pair of corners in the other diagonal direction of the printed circuit board 14 is placed and supported on the board support surface 40 of the positioning support part 24b. Further, although not shown, the central portion of the outer peripheral edge portion on the long side of the printed circuit board 14 is placed on and supported by the substrate support surface 46. As a result, the printed circuit board 14 is superimposed on the overlapping surface 22 while being separated by the protruding height dimension of the substrate support surfaces 26, 40, 46.

  As shown in FIG. 4, the engagement portion 48 of the printed circuit board 14 is engaged with the arcuate surface 34 of the positioning protrusion 30 in a state where the positioning support portion 24 a is placed on the substrate support surface 26. Due to the engaging action of the engaging portions 48 on the positioning protrusions 30, relative displacement of the printed circuit board 14 with respect to the accommodation case 12 in the diagonal direction in which the positioning support portions 24a and 24a are positioned is restricted. .

  On the other hand, as shown in FIG. 5, the mounting screw 54 is screwed into the screw hole 38 in the state where the screwing portion 50 of the printed circuit board 14 is superimposed on the substrate support surface 40 on the positioning support portion 24 b. As shown in FIG. 6, the screwing amount of the mounting screw 54 is defined by the head 56 of the mounting screw 54 being locked to the protruding end surface 44 of the locking protrusion 42. As a result, the mounting screw 54 is positioned outward from the substrate support surface 40, and the screwing portion 50 placed on the substrate support surface 40 is sandwiched between the substrate support surface 40 and the head 56 of the mounting screw 54. In particular, the protrusion height dimension h2 of the locking protrusion 42 from the substrate support surface 40 is larger than the thickness dimension t of the screwing portion 50 of the printed circuit board 14, so that the fixing support 42 is attached to the substrate support surface 40. The distance between the opposing surfaces of the head portion 56 of the screw 54 is made larger than the thickness dimension t of the screwing portion 5 in the printed circuit board 14, and the head portion 56 of the mounting screw 54 is connected to the screwing portion of the printed circuit board 14. 50 are overlapped with a slight gap.

  Thereby, the screwing part 50 is non-fixedly hold | maintained between the board | substrate support surface 40 and the head part 56 of the attachment screw 54. FIG. As a result, the printed circuit board 14 is prevented from being detached from the housing case 12, and the printed circuit board 14 is assembled to the housing case 12. At the same time, the relative displacement of the printed circuit board 14 with respect to the accommodation case 12 in the diagonal direction in which the positioning support portions 24 b and 24 b are positioned and the displacement in the lifting direction from the substrate support surface 40 are restricted.

  In this way, the printed circuit board 14 is aligned and superimposed on the overlapping surface 22, whereby the connection terminals 20 are respectively inserted into the through holes 52 of the printed circuit board 14. Each connection terminal 20 is soldered to the printed circuit board 14 to be electrically connected to a printed wiring (not shown) provided on the printed circuit board 14.

  According to the housing case with a substrate 10 having such a structure, both sides in one diagonal direction of the printed circuit board 14 are sandwiched between the positioning protrusions 30 and 30 of the pair of positioning support portions 24a and 24a, and the other diagonal direction. Is sandwiched between the mounting screws 54 and 54 of the pair of positioning support portions 24b and 24b, the relative displacement in the surface direction of the printed circuit board 14 with respect to the housing case 12 can be limited. Thereby, the printed circuit board 14 can be stably and easily aligned with a predetermined position with respect to the housing case 12, and the connection terminal 20 can be easily inserted into the through hole 52. In particular, the guide surface 36 formed on the positioning protrusion 30 can more easily align the printed circuit board 14 with the overlapping surface 22. Further, since the engagement between the positioning protrusion 30 and the engaging portion 48 is started before the connection terminal 20 is inserted into the through hole 52, the connection terminal 20 and the through hole 52 are positioned in advance. Can be inserted more easily and reliably. Further, by sandwiching the screwing portion 50 between the head 56 of the mounting screw 54 and the board support surface 40, it is possible to reliably prevent the printed board 14 from being detached from the housing case 12.

  Further, in a state where the printed board 14 is assembled to the housing case 12, the positioning protrusion 30 and the mounting screw 54 are positioned outward in the diagonal direction of the printed board 14, and the printed board 14 has any positioning support portion 24a, 24b is also in an unfixed state. Thereby, for example, even when the housing case 12 is deformed by the heat of the circuit mounted on the vehicle or the heat at the time of soldering, there is almost no possibility that an external force due to the deformation of the housing case 12 is exerted on the printed circuit board 14 and the occurrence of solder cracks. It can be effectively prevented. In particular, the engaging portion 48 and the screwing portion 50 of the printed circuit board 14 are both arc-shaped cutouts of approximately ¼ circumference at the corners of the printed circuit board 14. Accordingly, the positioning protrusion 30 and the mounting screw are deformed by the deformation of the housing case 12 while ensuring a stable positioning effect by sufficiently securing an engagement region between the positioning protrusion 30 and the mounting screw 54 at the time of alignment. When 54 is relatively displaced, the follow-up of the printed circuit board 14 can be effectively prevented without being restrained by the positioning protrusions 30 and the mounting screws 54.

  In addition, since the screwing amount of the mounting screw 54 is defined by the locking projection 42 of the positioning support portion 24b, the mounting screw 54 is firmly fixed to the housing case 12, while the printed board 14 is not fixed. It can be assembled to the housing case 12 with almost no tightening force, and the possibility of damage to the printed circuit board 14 during assembly can be reduced. Furthermore, by forming a gap between the screwing portion 50 and the mounting screw 54, it is possible to reduce the possibility that the printed circuit board 14 is deformed following the warp of the housing case 12 due to heat or the like.

  In addition, since the positioning support portions 24a and 24b and the corresponding engaging portions 48 and screwing portions 50 of the printed board 14 are provided at the square portions of the printed board 14, the central portion of the printed board 14 is arranged. It can be used effectively.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited by the specific description. For example, the notch shape of the engagement portion and the screwing portion on the printed circuit board is not limited to the ¼-circular arc shape as in the above-described embodiment, but is a C shape, a linear shape, other arbitrary polygonal shapes, etc. Can be adopted as appropriate.

  In the embodiment, a slight gap is formed between the head 56 of the mounting screw 54 and the screwing portion 50 of the printed circuit board 14. For example, the height dimension h2 of the locking projection 42 is set as follows. The thickness dimension of the screwing part 50 in the printed circuit board 14 may be substantially equal to t, and the head part 56 may be brought into contact with the screwing part 50. In this way, it is possible to more effectively prevent displacement of the printed circuit board 14 from the overlapping surface 22 while preventing the printed circuit board 14 from following the deformation of the housing case 12.

  Furthermore, in the above-described embodiment, the connection terminal protrudes from the storage case, but the present invention is widely applicable to a storage case with a substrate to which a printed circuit board is assembled, and a storage case without a connection terminal is provided. It is also possible to use it. Even when a storage case without a connection terminal is used, it is possible to reduce solder cracks by reducing stress on the soldering portion by suppressing the follow-up of the printed circuit board to deformation of the storage case due to heat.

10: storage case with substrate, 12: storage case, 14: printed circuit board, 20: connection terminal, 22: overlapping surface, 24a, b: positioning support portion, 26, 40: substrate support surface, 30: positioning projection, 38: Screw hole, 48: Engagement part, 50: Screw fixing part, 52: Through hole, 54: Mounting screw, 56: Head

Claims (4)

In a storage case with a substrate in which a rectangular printed circuit board is superimposed and assembled on a synthetic resin storage case,
Positioning support portions are respectively formed in portions corresponding to the squares of the printed circuit board on the overlapping surface of the printed circuit boards in the housing case, and the square support portions of the printed circuit boards are mounted on the positioning support portions. A substrate support surface that is placed and supported is provided, and a pair of positioning support portions that are positioned in one diagonal direction are provided with positioning protrusions that are positioned outward from the substrate support surface. In addition, a pair of corner portions of the corresponding printed circuit board is formed with a notch-shaped engaging portion, and each of the engaging portions engages with each positioning protrusion in the printed circuit board. While the displacement in one diagonal direction is restricted, the pair of positioning support portions positioned in another diagonal direction are positioned outward from the substrate support surface, respectively. A mounting screw is screwed, and a pair of corners of the corresponding printed circuit board is formed with a notch-shaped screwing portion, and the board support surface of each screwing portion and the mounting The board characterized in that the displacement in the other diagonal direction of the printed circuit board and the displacement in the lifting direction from the board support surface are regulated by a non-fixed holding action between the heads of the screws. With storage case.   The accommodation case with a substrate according to claim 1, wherein a distance between opposing surfaces of the substrate support surface and a head portion of the mounting screw is larger than a thickness dimension of the screwing portion.   The housing case with a substrate according to claim 1, wherein a connection terminal to be soldered to the printed board protrudes from the housing case.   The housing case with a substrate according to claim 3, wherein in the housing case, a protruding height of the positioning protrusion from the substrate support surface is larger than a protruding height of the connection terminal from the substrate support surface.

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