JP2008171837A - Substrate supporting structure of electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate supporting structure of an electronic apparatus which performs sorting and discarding of plastic products and circuit boards easily by making it possible to fix a plurality of circuit boards in a case while positioning and to separate them by opening/closing the case using one screw. <P>SOLUTION: A first substrate supporting portion is located at a position retreated by a predetermined distance from the opening end edge of the side panel of one case 1 and has a retreat side supporting surface abutting against one side of a circuit board 2 on one stage at a scheduled fixing position, and a second substrate supporting portion 110 is located at a position advanced by a predetermined distance from the opening end edge of the side panel of the other case 5 to the counterpart case side and has an advance side supporting surface abutting against the other side of the circuit board 2 on the stage. The front case 1 and the rear case 5 are coupled, substantially in the center of a front panel or a rear panel, by means of one screw 6 which is driven into the other case 1 while penetrating the one case 5 and a plurality of circuit boards 2, 3 and 4 in the front and back direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a board support structure for an electronic device for housing a plurality of circuit boards in a plastic case.

  A so-called all-in-one type programmable controller (hereinafter referred to as PLC) includes a CPU board, an I / O board, and a power board in a plastic case having a DIN rail mounting groove on the back side. A plurality of circuit boards are accommodated. Electronic components containing various useful precious metals are mounted on each circuit board accommodated in the case by soldering.

  For this reason, when disposing of electronic equipment that contains multiple circuit boards in a plastic case, separate the case and each circuit board and discard them separately for effective use of resources. It is desirable to do.

Conventionally, as a board support structure for this type of electronic equipment, screw holes are formed on the case side, while screw insertion holes are formed on each of the circuit boards, and the two are tightened and fixed with screws. There are known snap-fit structures that form board mounting grooves on the side, and insert pieces on each circuit board side. (For example, refer to Patent Document 1).
Japanese Patent Laid-Open No. 11-224111

  However, in the above-described board support structure, the case and the circuit board are firmly connected with screws, so even if the case is opened, the case and each circuit board are connected. In order to separate them, it is necessary to use a screwdriver to loosen each screw one by one for each circuit board. On the other hand, the case and the circuit board are strong even with a snap-fit structure. Even if the case is opened, in order to separate the case and each circuit board, the work of bending each circuit board one by one and pulling the insertion piece out of the groove is required. In both cases, since the man-hours required for disassembly are large, there is a problem that the circuit board is easily separated without being separated.

  The present invention has been made paying attention to the above-mentioned problems, and the purpose of the present invention is to close a case and then tighten a single screw so that a plurality of circuit boards can be simultaneously placed in the case. In addition to being able to position and fix, by loosening one of the screws and opening the case, multiple circuit boards can be separated from the case alone, facilitating the separation and disposal of plastic products and circuit boards. An object of the present invention is to provide a substrate support structure for an electronic device.

  Other objects and operational effects of the present invention will be easily understood by those skilled in the art by referring to the following description of the specification.

  The above technical problem can be solved by a substrate support structure for an electronic device described below.

  This board support structure for an electronic device is for accommodating a plurality of circuit boards arranged in multiple stages in the front-rear direction in a plastic case. Here, the three-dimensional shape of the case is not necessarily limited to a rectangular parallelepiped shape.

  The case is constituted by two parts, a front case that forms a predetermined region on the front side of the case and a rear case that forms a predetermined region on the rear side of the case. Here, the front-side predetermined area and the rear-side predetermined area are, for example, when the case is divided front and back in a one-to-one manner, each of the front and rear half areas becomes a predetermined area and is divided into one to two. If it is, the front 1/3 and the rear 2/3 are the predetermined areas.

  The front case includes a front panel that forms a front surface of the case, and a side panel that extends from the periphery of the front panel toward the rear case. At this time, if the case is a rectangular parallelepiped or a hexahedron, it goes without saying that the side panels include left and right side panels and upper and lower side panels, respectively.

  The rear case includes a rear panel that forms a rear surface of the case, and a side panel that extends from the periphery of the rear panel toward the front case. Needless to say, if the case is a rectangular parallelepiped or a hexahedron, the side panels include left and right side panels and upper and lower side panels, respectively.

  A first substrate support portion and a second substrate support portion are provided on the inner surface of the side panel of the front case or the rear case at an appropriate interval in the circumferential direction.

  The first board support portion is located at a position retracted from the opening edge of the side panel of one case (for example, the front case or the rear case) by a predetermined distance, and the first stage circuit board is in the position to be attached. It has a retreat-side support surface that should come into contact with the surface on one side (for example, the rear case side or the front case side).

  The second substrate support portion is located at a position where it has advanced from the opening edge of the side panel of the other case (for example, the rear case or the front case) to the counterpart case side (the front case side or the rear case side) by a predetermined distance. And an advancing support surface to be brought into contact with the surface on the other side (front case side or rear case side) of the one-stage circuit board.

  The front case and the rear case are connected to each other by a single screw that passes through one case and a plurality of circuit boards in the front-rear direction and is screwed into the other case at the center of the front panel or the rear panel. . Here, “substantially the center” includes not only the physical center but also the central predetermined region where the tightening pressure can be uniformly applied to the entire case by tightening the point. is there.

  As a result, the circuit board of the first stage has the retracted side supporting surface of the first board supporting part of one case and the advancing side supporting surface of the second board supporting part of the other case at appropriate positions on the peripheral edge thereof. And is fixed only through the tightening pressure of the one screw.

  According to such a configuration, it is possible to position and fix a plurality of circuit boards in the case at the same time by simply tightening one screw after closing the case, and loosening the one screw to loosen the case If the circuit board is opened, the plurality of circuit boards are separated from the case alone, so that in this type of electronic device, it is easy to separate and discard the plastic product and the circuit board.

  In the above-described substrate support structure, the first substrate support portion and the second substrate support portion are shared by one substrate support portion, and the shared substrate support portion includes the inside of the case (for example, the front support). The back side support surface to be brought into contact with the surface on one side (for example, the rear case side or the front case side) of the one-stage circuit board to be accommodated in the case or the rear case) Both the advancing support surface to be brought into contact with the surface on one side (for example, the rear case side or the front case side) of the one-stage circuit board to be accommodated in the rear case or the front case) It may be provided.

  According to such a configuration, by disposing the plurality of substrate support portions in a concentrated manner, it is possible to improve the releasability during plastic molding and improve the molding accuracy of the entire case.

  In the substrate support structure described above, the front case side boss and the rear case side boss pass through a slight gap (corresponding to the tightening allowance) on the opposing inner surfaces of the front panel of the front case and the rear panel of the rear case. A screw insertion hole is formed in the shaft center of one of the bosses so that an entrance is opened on the surface of the front panel or the rear panel and a screw head is prevented from passing through at the bottom. In addition, a screw hole for opening an inlet is formed at the tip of the boss on the shaft center of the other boss, and further, each of the plurality of circuit boards may have a space that allows the boss to pass therethrough. Good.

  According to such a configuration, the screw length required for fastening the front case and the rear case and the multilayer support of the board is shortened, and the workability or operability at the time of screwing work is improved. Can do.

  In the board support structure described above, the outer surface of the front case side boss and / or the rear case side boss has a surface on one side (for example, the rear case side or the front case side) of the circuit board at any stage. Or the support part which has a support surface which should contact | abut the surface of the other side (for example, the front case side or the rear case side) may be formed.

  According to such a configuration, each of the circuit boards arranged in multiple stages is firmly supported by the case not only at its outer peripheral edge but also at the center of the case. Due to the instability of the support, the board-to-board connector that had to be arranged at the outer peripheral edge of the board can be arranged at the center of the board, and the degree of freedom of arrangement of the board-to-board connector is increased.

  In the above-described substrate support structure, a substrate retaining member that protrudes and retracts in conjunction with whether or not the counterpart case is attached is provided on the front side of the retracted support surface located in the back of the front case or the rear case. Good.

  According to such a configuration, with respect to the receding side support surface located in the back part of the front case or the rear case, it is possible to extend the second board support part beyond the necessity without extending it into the counterpart case. It is possible to prevent the substrate supported by the portion from coming off, and it is possible to improve the ease of forming the second substrate support portion or the operability in the substrate mounting operation.

  According to the present invention, after closing the case, it is possible to simultaneously position and fix a plurality of circuit boards in the case by simply tightening one screw, and loosen the one screw to open the case. For example, it is possible to provide a substrate support structure for an electronic device that facilitates the separation and disposal of a plastic product and a circuit board by separating a plurality of circuit boards from the case alone.

  Hereinafter, a preferred embodiment of a substrate support structure for an electronic apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

  A perspective view showing the external appearance of the electronic device in an assembled state is shown in FIG. 1, and an exploded perspective view is shown in FIG. As is clear from these drawings, an electronic apparatus (in the illustrated example, an all-in-one type PLC) 10 to which the present invention is applied includes a plurality of circuit boards (in the illustrated example, in the illustrated example). 3 circuit boards (CPU board 2, I / O board 3 and power supply board 4) are accommodated in multiple stages in the front-rear direction.

  As is well known, this type of PLC has an input terminal block to be connected to an external input device, an output terminal block to be connected to an external output device, and an input signal from the input terminal block. An input circuit for capturing, an output circuit for sending output signals to the output terminal block, a user program memory for storing user programs, an input / output memory for storing external input / output signals, And an arithmetic processing unit including a microprocessor, an ASIC, and the like.

  The processing executed by the arithmetic processing unit includes an input update process for writing an input signal (input data) taken from the outside via an input circuit and an input terminal block into an input area of the input / output memory, and an input / output memory Following the output update process that reads the output signal (output data) from the output area and sends it to the outside via the output circuit and output terminal block, and the input / output update process, the user refers to the contents of the input / output memory. Examples include instruction execution processing for executing the program and rewriting the contents of the input / output memory with the execution result.

  In addition to the above-described memory elements that function as user program memory and input / output memory, the CPU board 2 is mounted with a microprocessor and ASIC that function as an arithmetic processing unit. In FIG. 2, reference numeral 8 indicates a communication connector (for example, RS232C) for downloading or uploading a user program or performing various internal settings via communication with an external personal computer or the like. Connectors). The I / O board 3 is mounted with circuit components corresponding to the above-described output terminal block 7a, input terminal block 7b, input circuit, output circuit, and the like. Furthermore, a heat generating circuit component such as a power transistor constituting a voltage stabilizing circuit is mounted on the power supply substrate 4.

  As shown in FIGS. 1 and 2, the case of the electronic device 10 is formed in a rectangular parallelepiped shape in this example, and includes a front case 1 that forms a predetermined area on the front side of the case, and a predetermined area on the rear side of the case. It is constituted by two parts separated from the rear case 5 to be formed. When the front case 1 and the rear case 5 are closed, the opening edges 111 and 511 of the cases 1 and 5 are configured to be aligned with each other.

  The front case 1 includes a front panel 101 that forms a front surface of the case, and four side panels that extend from the periphery of the front panel 101 to the rear case 5 side. In this example, the side panel includes a left side panel 102, a right side panel 103, a lower side panel 104, and an upper side panel 105.

  A perspective view of the front case placed inside up is shown in FIG. As shown in the figure, the front panel 101 and the upper and lower side plates 104 and 105 of the front case 1 are largely cut away to expose terminal blocks 7a and 7b, which will be described later. 107 is formed. Reference numeral 108 denotes a window for exposing the communication connector.

  On the inner side of the front case 1, there are four rectangular parallelepiped projections 109, 109... That function as first substrate support portions, and four thin plate-like projections that function as second substrate support portions. 110, 110... Are provided.

  The protrusions 109 functioning as the first substrate support portions are one by one so as to face each other with the lower space 106 interposed therebetween at a corner portion where the inner surface of the lower side panel 104 and the inner surface of the front panel 101 intersect. In addition, the corners where the inner surface of the upper side panel 105 and the inner surface of the front panel 101 intersect are arranged one by one so as to face each other with the upper space 107 therebetween.

  The receding side support surface 109a, which is the upper surface of each of the four protrusions 109, 109..., Is in a position that is receded by a distance L1 from the opening edge 111 of the front case 1. As shown in FIG. 8, the height of the backward-side support surface 109a is such that the CPU substrate 2 is in contact with the upper surface (surface on the front case side) of the CPU substrate 2 when the CPU substrate 2 is at a predetermined mounting position P1. It is set to be.

  The protrusions 110 functioning as the second substrate support portions are symmetrical with respect to the center line extending in the left-right direction of the case at the two inner surfaces of the left side panel 102 and the two inner surfaces of the right side panel 103, respectively. Is arranged.

  The advancing side support surface 110a, which is the upper surface of each of the four protrusions 110, 110..., Is in a position protruding from the opening edge 111 of the front case 1 by a distance L2, as shown in FIG. As shown in FIG. 8, the height of the advancing side support surface 110a is set on the upper surface (front case side surface) of the I / O substrate 3 when the I / O substrate 3 is at a predetermined mounting position P2. The height is set so as to abut.

  The rear case 5 includes a rear panel 501 that forms the rear surface of the case, and four side panels that extend from the periphery of the rear panel 501 to the front case side 1. In this example, the side panel includes a left side panel 502, a right side panel 503, a lower side panel 504, and an upper side panel 505.

  A perspective view of the rear case placed inside up is shown in FIG. As shown in the figure, on the inner surface of the side panel of the rear case 5, four composite structures 507 and 507 having both a function as a first substrate support portion and a function as a second substrate support portion. ... are provided. More specifically, the composite structures 507, 507... Are formed on the inner surfaces of the upper and lower side panels 504, 505 in the vicinity of each of the four corner portions where the adjacent side panels of the rear case 5 intersect. Is arranged.

  Each of the composite structures 507 includes a rectangular thin plate-like base portion 508 that is elongated in the front-rear direction (vertical direction in FIG. 4) of the case, and both side edges of the lower predetermined length portion of the thin plate-like base portion 508. Two stepped protrusions 509 and 509 provided along the part, and a cantilever-like movable piece 510 provided at the center in the left-right direction of the upper predetermined length portion of the thin plate-like base 508. And have.

  The cantilevered movable piece 510 has upper and lower side panels 504 formed by a left side slit 510a, a right side slit 510b, and a lower end slit 510c, with the left and right center portions of the thin plate-like base portion 508 left and right. , 505 are separated from each other. The structure and operation of the movable piece 510 will be described in detail later with reference to FIGS. 11 and 12.

  Backward-side support surfaces 509a and 509a, which are upper surfaces of the step portions near the lower end portions of the left and right stepped ridge portions 509 and 509, are formed from the opening edge 511 of the rear case 5 as shown in FIGS. Is also in a position retracted by a distance L31. As shown in FIG. 8, the height of the backward support surface 509a contacts the lower surface of the edge of the power supply substrate 4 (the surface on the rear case side) when the power supply substrate 4 is at the expected mounting position P3. It is set to be high.

  The retreat-side support surface 509b, which is the upper surface of the upper ends of the left and right stepped protrusions 509 and 509, is in a position retreated by a distance L32 from the opening edge 511 of the rear case 5, as shown in FIG. . As shown in FIG. 8, the height of the backward support surface 509b is such that when the I / O board 3 is at a predetermined mounting position P2, the lower surface of the edge of the I / O board 3 (the surface on the rear case side). ) Is set so as to be in contact with the height.

  The advance side support surface 507a, which is the upper surface of the upper end portion of the thin plate-like base portion 508, has advanced (extended) by a distance L33 from the opening edge 511 of the rear case 5, as shown in FIGS. In position. As shown in FIG. 8, the height of the advancing side support surface 507 a abuts against the lower surface of the edge of the CPU board 2 (the surface on the rear case side) when the CPU board 2 is at the predetermined mounting position P <b> 1. It is set to be high.

  As shown in FIGS. 11 and 12, the movable piece 510 has a cantilever structure in which the upper end portion is supported by a thin plate-like base portion 507, and the upper end portion is made flexible by the flexibility of plastic. By bending as a fulcrum, the lower end 510e can be projected and retracted with a predetermined stroke to the inside of the rear case 5. The lower end portion 510e functions as a substrate retaining member that protrudes and retracts in conjunction with whether or not the counterpart case 1 is mounted on the front side of the retreat side support surfaces 509a and 509a located at the back of the rear case 5.

  As shown in FIG. 12, a tapered surface 510d is formed on the outer surface of the upper portion of the movable piece 510 so as to increase in thickness from the top to the bottom (from the front case side to the rear case side). Yes. For this reason, when the opening edge 111 of the front case 1 and the opening edge 511 of the rear case 5 are brought close to each other to join them, the inner surfaces of the upper and lower side panels 104 and 105 on the front case 1 side and the rear case 5 side When the movable piece 510 is in contact with the taper surface 510d of the movable piece 510 while sliding, the movable piece 510 is entirely pushed inwardly of the rear case. As a result, the lower end 510e of the movable piece 510 is Projects a predetermined distance inward.

  Then, as estimated from FIG. 11, the lower surface of the lower end portion 510e of the movable piece 510 is the edge of the power supply substrate 4 placed on the back-side support surfaces 509a and 509a of the left and right stepped ridge portions 509 and 509. It will be in the state which opposes a part upper surface through a slight clearance gap, and, thereby, the power supply board 4 is prevented from coming off and is held at a predetermined mounting position P3 as shown in FIG.

  On the other hand, if the case is uncoupled and the case is separated into the front case 1 and the rear case 5, it is bent by the elasticity of the plastic, and the movable piece 510 moves to the outside of the rear case as a whole. As a result, the lower end 510e of the movable piece 510 moves by a predetermined distance in the outer direction of the rear case.

  Then, the lower surface of the lower end portion 510e of the movable piece 510 is removed from a position facing the upper surface of the edge of the power supply substrate 4 placed on the left and right stepped protrusions 509 and 509, as shown in FIG. Thus, the power supply board 4 can be detached from the rear case 5.

  Next, a structure for fastening and fixing the front case 1 and the rear case 5 will be described. As apparent from FIGS. 3, 4, and 8, the front case boss 112 and the rear case having a circular cross section are respectively formed on the opposing inner surfaces of the front panel 101 of the front case 1 and the rear panel 501 of the rear case 5. The side boss 512 is formed so as to project into a butted state (axial center aligned state) through a slight gap as a fastening allowance.

  A screw insertion hole 512a is formed in the shaft center of the rear case side boss 112 so as to open the inlet 512b on the surface of the rear panel 501 and prevent the head 6a of the screw 6 from passing through at the bottom thereof. A screw hole 112a is formed in the shaft center of the boss.

  Further, the CPU board 2 is formed with a circular hole 201 which is a space for allowing the front case side boss 112 to pass therethrough, and each of the I / O board 3 and the power supply board 4 has a rear case side boss. Circular holes 301 and 401 are formed as voids for allowing 512 penetration. Needless to say, notches and voids are formed in the peripheral portions of the circuit boards 2, 3, and 4 to allow the passage of the board support parts that are not related to the support action of the board. .

  Next, the operation of the substrate support structure for an electronic apparatus having the above configuration will be described. In assembling the electronic device 10, first, as shown in FIG. 4, the rear case 5 is placed with its inside facing upward, and in this state, the power supply board 4 is first introduced into the rear case 5. The four corner edges are positioned so as to be placed on each of the receding support surfaces 509a of the four composite structures 507. Next, the I / O substrate 3 is introduced into the rear case 5 in the same manner, and the edge portions of the four corners are positioned on the receding support surfaces 509b of the four composite structures 507, respectively. Finally, the CPU board 2 is placed in a state parallel to the rear panel 501, and the four corner edges are positioned on the advancing side support surfaces 507a of the four composite structures 507. Thereafter, the front case 1 is placed on the rear case 5 so that the inside of the case 1 faces downward, and the two cases 1 and 5 are brought close to each other so that the opening edges 111 and 511 face each other. As shown in FIG. 1, the case is in a closed state.

  After that, as shown in FIG. 7, the screw 6 is inserted into the screw insertion hole 512a of the rear case side boss 512 from the inlet opening 512b provided on the rear surface of the rear case 5, and this screw 6 is inserted into the tip of the driver. To push the bottom of the screw insertion hole 512a. Then, the tip of the screw 6 passes through the small hole at the bottom of the screw insertion hole 512 a and is screwed into the screw-in hole 112 a from the tip opening of the front case side boss 112. In this state, when the screw 6 is tightened by a predetermined tightening allowance, the head portion 6a of the screw is prevented from passing by the small hole at the bottom of the screw insertion hole 512a. When approaching, finally, it will be in a butt | matching state and the coupling | bonding of both cases 1 and 5 will be completed.

  At this time, since both the bosses 112 and 512 are arranged at the substantially central portion of the case, the pressure generated by the tightening of the screws 6 acts evenly on the four corners of the case. 3 is securely held and fixed at each of the four corners. Further, since the screw 6 is screwed into the tip of the screw hole 112a of the mating boss 112 at the bottom of the screw insertion hole 512a in the boss 512, the required length of the screw 6 is significantly shorter than the thickness in the front-rear direction of both cases. The workability or operability in the screwing work is improved. Furthermore, in this example, since the screw insertion hole is provided in the rear case side boss 512, the inlet 512b of the screw insertion hole 512a is concealed on the back side of the case, and the appearance of the front panel 101 of the case is not impaired. . The screw hole 112a may be a tapped screw hole or a simple cylindrical hole that is not tapped. However, in the case of a cylindrical hole, the screw may be a screw having a screwing function such as an iron plate screw or a wood screw.

  In this coupling completed state, the power supply board 4 has the four corners at the lower end of the movable piece 510 of the rear-side support surface 509a of the composite structure 507 on the rear case 5 side and the composite structure 507 on the rear case 5 side. It is supported in a state of being held between the lower surface of 510e with appropriate play. Further, as shown in FIG. 9, the I / O substrate 3 has four corners at the back side support surface 509b of the composite structure 507 on the rear case 5 side and the thin plate-like protrusion 110 on the front case 1 side. It is supported in a state of being firmly held by the advancing side support surface 110a. Further, the CPU substrate 2 is supported in a state where the four corners thereof are firmly sandwiched between the advancing side support surface 507a of the composite structure 507 on the rear case 5 side and the retreat side support surface 109a on the front case 1 side. . Accordingly, the three circuit boards 2, 3, 4 are reliably supported in the case inner space formed by the front case 1 and the rear case 5 only by tightening the single screw 6.

  When disassembling the electronic device 10, if a screwdriver is inserted into the screw insertion hole 512 a from the screw insertion opening 512 b on the back of the electronic device 10, and the screw 6 located at the bottom is loosened, the front case 1 and The rear case 5 is gradually separated from the rear case 5 so that the screw 6 comes out of the screw hole 112a and the case can be separated into the front case 1 and the rear case 5. Thereafter, if the front case 1 is pulled away from the rear case 5, the urging force against the movable piece 510 is released, the lower end portion 510e is retracted outward from the case, and the power supply board 4 can be detached from the case. The substrate 2 and the I / O substrate 3 are also released from the case by being released from the holding force by the advance side support surface and the retreat side support surface.

  Thus, according to this board support structure, the two circuit boards 2 and 3 can be simultaneously positioned and fixed in the case by simply tightening the single screw 6 after closing the cases 1 and 5. At the same time, if the one screw 6 is loosened and the cases 1 and 5 are opened, the two circuit boards 2 and 3 are separated from the case alone, so that the plastic products 1 and 5 and the circuit in this type of electronic device 10 are separated. Sorting and discarding with the substrates 2 and 3 can be facilitated, which contributes to effective utilization of resources.

  In addition, the circuit board (the power supply board 4 in the illustrated example) housed in the rear part of the rear case 5 is not sandwiched between the two cases 1 and 5 but is sandwiched only by the mechanism on the rear case 5 side. As a result, it is not necessary to extend a long protrusion from the front case 1 side to the rear case 5 side to form an advancing side support surface. There is.

  In the above embodiment, the circuit boards 2 and 3 are supported by the cases 1 and 5 at the four corners. However, as shown in FIGS. If the case-side boss 512 is used, it is possible to support the circuit boards 2 and 3 even at the center thereof.

  That is, in the example shown in FIG. 5, around the front case side boss 112, four protrusions 113, 113... Is formed along the longitudinal direction of the boss. The retreat side support surface 113a which is each upper end surface of these protrusions 113 has the same height as the retreat side support surface 109a of the protrusion 109 on the front case 1 side. Similarly, in the example shown in FIG. 6, around the rear case-side boss 512, there are four protrusions 513, 513,. .. are formed along the longitudinal direction of the boss. The retreat side support surface 513a which is each upper end surface of these protrusions 513 has the same height as the retreat side support surface 509b of the composite structure 507 on the rear case 5 side.

  According to such a configuration, as shown in FIG. 10, the CPU substrate 2 and the I / O substrate 3 are supported by the case not only at the peripheral portion but also at the central portion. Even if the board connector 9a is arranged on the upper surface of the I / O board 3 and the board connector 9b is arranged on the lower face of the CPU board 2, respectively, Since 3 does not bend, the connector can be securely connected. Conventionally, since the circuit board cannot be supported at the center of the case with respect to the case, there has been a layout restriction that the arrangement of the board connector is limited to the peripheral part of the board. According to the configuration in which the support portions are provided on the bosses of both cases, there is an advantage that such layout restrictions are eliminated.

  According to the present invention, after closing the case, it is possible to simultaneously position and fix a plurality of circuit boards in the case by simply tightening one screw, and loosen the one screw to open the case. For example, since a plurality of circuit boards are separated from the case alone, it is possible to facilitate separation and disposal of plastic products and circuit boards in this type of electronic equipment, which contributes to effective use of resources.

It is a perspective view which shows the external appearance of the electronic device in an assembly completion state. It is a disassembled perspective view of an electronic device. It is a perspective view of the front case set | placed inside up. It is a perspective view of the rear case set | placed inside up. It is a perspective view of a front case (modification) placed with the inside facing upward. It is a perspective view of a rear case (modification) placed with the inside facing upward. It is a perspective view of the electronic device seen from diagonally backward. It is the VIII-VIII sectional view taken on the line of the electronic device shown in FIG. It is explanatory drawing which shows the support structure of a circuit board edge part. It is explanatory drawing which shows the support structure of a circuit board center part. It is explanatory drawing which looked at the support structure of the bottom board | substrate of a rear case from the case inner side. It is explanatory drawing which looked at the support structure of the bottom substrate of a rear case from the case side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front case 2 CPU board 3 I / O board 4 Power supply board 5 Rear case 6 Screw 6a Screw head 7a Terminal block 7b Terminal block 8 Communication connector 10 Electronic device 101 Front panel 102 Left side panel 103 Right side panel 104 Bottom Side panel 105 Upper side panel 106 Lower space 107 Upper space 108 Window 109 Projection portion 109a Retraction side support surface 110 Projection portion 110a Advancement side support surface 111 Open edge 112 Boss 112a Screw insertion hole 113 Projection portion 113a Support surface 201 Hole 202 Upper space 203 Lower space 401 Hole 402 Notch 501 Rear panel 502 Left side panel 503 Right side panel 504 Lower side panel 505 Upper side panel 506 DIN rail fitting groove 507 Composite structure 507a Advance side support surface 508 Thin plate shape Base 509 Stepped ridge 509a Retraction side support surface 509b Retraction side support surface 510 Movable piece 510a Left side slit 510b Right side slit 510c Lower end slit 510d Tapered surface 510e Lower end 511 Open end edge 512 Boss 512a Screw-in hole 513 Projection 513a Support surface

Claims (5)

A substrate support structure for an electronic device for housing a plurality of circuit boards arranged in multiple stages in a front-rear direction in a plastic case,
The case is
The front case that forms the predetermined region on the front side of the case and the rear case that forms the predetermined region on the rear side of the case are separated and configured.
The front case
A front panel that forms the front surface of the case, and a side panel that extends from the periphery of the front panel toward the rear case, and the rear case is
A rear panel that forms the rear surface of the case, and a side panel that extends from the periphery of the rear panel toward the front case,
The inner surface of the side panel of the front case or the rear case is provided with a first substrate support portion and a second substrate support portion with an appropriate interval in the circumferential direction,
The first board support part is in a position retracted by a predetermined distance from the opening edge of the side panel of one case, and abuts against the surface on one side of the circuit board of the first stage at the position to be attached. Has a retreat side support surface,
The second substrate support portion is located at a position advancing to the counterpart case side by a predetermined distance from the opening edge of the side panel of the other case, and is in contact with the surface on the other side of the circuit substrate of the first stage. Have a support surface to advance,
The front case and the rear case are joined by a single screw that passes through one case and multiple circuit boards in the front-rear direction and is screwed into the other case at the approximate center of the front panel or rear panel. ,
As a result, the circuit board of the first stage has the retracted side supporting surface of the first board supporting part of one case and the advancing side supporting surface of the second board supporting part of the other case at appropriate positions on the peripheral edge thereof. A substrate support structure for an electronic device, wherein the substrate support structure is fixed only through the clamping pressure of the one screw.   The first substrate support portion and the second substrate support portion are shared by one substrate support portion, and the shared substrate support portion includes a circuit board of one stage to be accommodated in the case. Both a retreat side support surface that should abut against one side surface and an advancing side support surface that should abut against one side surface of the one-stage circuit board to be accommodated in the counterpart case are provided. The board | substrate support structure of the electronic device of Claim 1 characterized by the above-mentioned.   The front case-side boss and the rear case-side boss are formed on the opposing inner surfaces of the front case front panel and the rear case rear panel so that the front case side boss and the rear case side boss face each other with a slight gap therebetween. A screw insertion hole is formed in the shaft center of the front boss panel or rear panel, and a screw insertion hole is formed at the bottom to prevent the screw head from passing through. 3. The electronic device according to claim 1, wherein a screw hole is formed in each of the plurality of circuit boards, and a space that allows penetration of the bosses is formed in each of the plurality of circuit boards. Substrate support structure.   On the outer periphery of the front case side boss and / or the rear case side boss, a support portion having a support surface to be brought into contact with one surface or the other surface of the circuit board at any stage is formed. The board | substrate support structure of the electronic device of Claim 3 characterized by these.   A board retaining member that protrudes and retracts in conjunction with whether or not the counterpart case is attached is provided on the front side of the backward support surface located at the back of the front case or the rear case. 5. A substrate support structure for an electronic device according to any one of 4 above.

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