WO2011145003A2

WO2011145003A2 - Board assembly structure

Info

Publication number: WO2011145003A2
Application number: PCT/IB2011/001468
Authority: WO
Inventors: Takashi Inose; Shinichi Yamamoto
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2010-05-20
Filing date: 2011-05-20
Publication date: 2011-11-24
Anticipated expiration: 2012-11-20
Also published as: CN102884874A; WO2011145003A3; JP2011243823A

Abstract

A board assembly structure includes a case (11) that includes an open portion, and inside of which a plurality of protracting terminals (20) are provided, a board (21) that includes conductive through-holes into which the protruding terminals (20) fit, a support portion (19a, 19b) that is provided on a bottom surface of the case (11) and supports the board, and a guide mechanism (17a, 17b, 18a, 18b) that includes an inclined surface and is provided on an inside surface of the case (11). The guide mechanism (17a, 17b, 18a, 18b) guides the board (21) that has been inserted into the case (11) through the open portion of the case (11), such that the conductive through-holes engage with the protruding terminals (20), and then stops guiding the board (21) before the board (21) becomes supported by the support portion (19a, 19b).

Description

BOARD ASSEMBLY STRUCTURE

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] The invention relates to an assembly structure for assembling a board to a case. More particularly, the invention relates to a board assembly structure for assembling a board to a case by fitting conductive through-holes in the board together with a plurality of protruding terminals provided inside the case. 2. Description of Related Art

[0002] Various methods for assembling a board are known. For example, one method for assembling a board involves providing a plurality of electric connectors on a circuit board referred to as a motherboard, and electrically connecting a circuit board referred to as a daughterboard to these electrical connectors. Another method for assembling a circuit board uses a type of electrical connector that connects a male connecting portion of a circuit board to a female terminal of a corresponding connector.

[0003] However, with these kinds of assembly methods, the circuit board must be precisely guided to mate (i.e., fit together) with the connector terminals from the initial stage of mating the circuit board with the terminals of the connectors. If the circuit board started to be mated with the connector terminals while misaligned, one of the terminals of the electrical connectors may be damaged.

[0004] Therefore, Japanese Patent Application Publication No. 2004-288453 (JP-A-2004-288453) describes an electrical connector that has i) first connectors with press-fit portions that are inserted into through-holes provided in a motherboard, ii) a plurality of daughterboards (i.e., chicklets) having a land pattern that is connected to these first connectors, and a connecting portion for connecting with second connectors that are arranged on the motherboard, iii) a precision guide mechanism that precisely guides the first connectors to mate with the second connectors while the first connectors are in the process of being mated with the second connectors, and iv) a housing that fixes these boards side by side. With this kind of structure, even if the alignment is quite rough, the connectors are able to be started being mated together, and a very precise fit can be achieved.

[0005] In recent years, module type onboard electronic equipment is being used to improve mounting ability in vehicles. For example, a mike module arranged in a vehicle cabin has a mike and a mike amp. The mike amp is mounted inside the mike module. With this kind of mike module, a terminal is provided on a bottom surface of a case that is open on one side. A board is mounted (i.e., assembled) in a location deep inside the case, i.e., a board is assembled in a case surrounded by walls, and electrically connected to the terminal on the bottom surface of the case. When connecting the board to the terminal, this connection is made using either an electrical connector (i.e., a press-fit connection), such as that described in JP-A-2004-288453, or by soldering.

[0006] In JP-A-2004-288453, even if the alignment is rough, the first connectors can start to be mated with the second connectors because the precision guide mechanism that precisely guides the mating at the stage when the first connectors and the second connectors are in the process of being mated together is provided. However, when assembling the board to the case that has peripheral walls while keeping the board horizontal and leaving a gap between the walls of the case and the board in order to prevent interference between the two, the precision guide mechanism is unable to be used. Therefore, a positioning operation to align the through-holes in the board with the positions of the terminals is necessary, which may reduce the efficiency of the board assembly operation.

[0007] In JP-A-2004-288453, the board is guided by the precision guide mechanism until the mating of the first connectors with the second connectors is complete. Therefore, if a jig is used to perform the mating, if the mating load is unstable due to variation in the precision guide mechanism, or if there is a difference between the heat expansion of the board and the heat expansion of the housing, stress may be generated on the board by the housing after the first connectors and the second connectors have been mated together. Also, if the terminal connection is made by soldering, a high temperature soldering iron may get close to the peripheral walls and the case that is made of resin may deform from the heat. Therefore, the external size must be increased so that space can be provided inside the case in advance so that the soldering iron will fit, and the work must be performed with the utmost care.

SUMMARY OF THE INVENTION

[0008] The invention thus provides a board assembly structure in which a board can be easily assembled even if there are peripheral walls, and which is able to inhibit the external size of the module from increasing, and in which workability is also able to be ensured.

[0009] A first aspect of the invention relates to a board assembly structure that includes a case that includes an open portion, and inside of which a plurality of protruding terminals are provided, a board that includes conductive through-holes into which the protruding terminals fit, a support portion that is provided on a bottom surface of the case and supports the board, and a guide mechanism that includes an inclined surface and is provided on an inside surface of the case. The guide mechanism guides the board that has been inserted into the case through the open portion of the case, such that the conductive through-holes engage with the protruding terminals, and then stops guiding the board before the board becomes supported by the support portion.

[0010] In the structure described above, the plurality of protruding terminals may be press-fit terminals, and the protruding terminals of the case may be electrically connected with the board by the through-holes of the board being fit together with the press-fit terminals.

[0011] In the structure described above, the plurality of protruding terminals may be provided so as to protrude upward.

[0012] In the structure described above, the guide mechanism may be provided · on a side surface of the case.

[0013] In the structure described above, the inclined surface of the guide mechanism may be inclined in a height direction of the case.

[0014] In the structure described above, a distance between a lower end of the guide mechanism and an upper end of the support portion may be greater than a thickness of the board.

[0015] In the structure described above, the guide mechanism may include a plurality of guide members, and the guide members may be provided on two of the side surfaces that are parallel to each other.

[0016] In the structure described above, the open portion may be formed on the side surface other than the two of side surfaces, and the guide mechanism may include the guide member that is provided on the side surface that faces the open portion.

[0017] According to the invention, a board can be assembled in a case having peripheral walls, while the board is kept horizontal. Moreover, the external size of the module is able to be inhibited from increasing, and workability is able to be ensured.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The foregoing and further objects, features and advantages of the invention will become apparent from the following description of example embodiments with reference to the accompanying drawings, wherein like numerals are used to represent like elements and wherein:

FIG. 1 is a perspective view of a mike module having a board assembly structure according to an example embodiment of the invention;

FIG 2 is a view of the mike module shown in FIG 1 with the board removed;

FIG 3 is a perspective view of a cover that covers the front of the mike module shown in FIG 1;

FIG 4 is a perspective view of the mike module shown in FIG 1 with the cover shown in FIG 3 attached;

FIGS. 5A to 5C are views illustrating an assembly method using support portions and a guide mechanism of the board assembly structure according to the example embodiment of the invention; and FIGS. 6 A and 6B are views of contact points of the support portions and the guide mechanism of the board assembly structure according to the example embodiment of the invention. DETAILED DESCRIPTION OF EMBODIMENTS

[0019] Hereinafter, example embodiments of the invention will be described with reference to the accompanying drawings.

[0020] FIG 1 is a view of a mike module 10 provided with a board assembly structure. The mike module 10 includes a swivel mike 12 that is mounted to a case 11, centered on a rotating shaft 13, a board 21 that has a mike amp circuit that amplifies a signal from the swivel mike 12, a mike wire 15 that connects the swivel mike 12 to the board 21, and press-fit terminals 20 that are protruding terminals that are connected to an external connector 16 and are used to output the signal amplified by the board 21 to the external connector 16. In the mike module 10, the electrical connection and the fixing of the board are both achieved by fitting the conductive through-holes in the board 21 together with the press-fit terminals 20.

[0021] The front of the case 11 in FIG 1 is open and guides 17a and 17b that guide the board 21 are provided on the back surface inside the case (i.e., on the surface facing the front). A slide 18a that guides the board 21 by an inclined surface, and a flange portion 19a that supports the board 21 inside the case 11, are provided on the left side surface inside the case 11. Similarly, a slide 18b that guides the board 21 by an inclined surface, and a flange portion 19b that supports the board 21 inside the case 11, are provided on the right side surface inside the case 11. Moreover, case fixing pawls 22 for fixing the case 11 to a vehicle are provided on the outside of the case 11. The guides 17a and 17b and the slides 18a and 18b each form an inclined surface that is inclined in the height direction (i.e., the vertical direction) of the case 11, and serve to guide the board 21 to a mating position such that the press-fit terminals come to be engaged with the conductive through-holes by the board 21 moving along the inclined surfaces. The guides 17a and 17b and the slides 18a and 18b are formed continuous in the height direction to above the flange portions 19a and 19b that serve as support portions for the board 21. The distance between the lower end of each guide 17a and 17b and the slide 18a and the 18b and the upper end of each flange portion 19a and 19b is set greater than the thickness of the board 21.

[0022]. The mike module 10 in FIG 1 is assembled with the mike wire 15 that connects the swivel mike 12 to the board 21 being extra long to both ensure the swivel amount of the swivel mike 12 and prevent the mike wire 15 from interfering with the operation of connecting the board 21 to the case 11. Therefore, the swivel mike 12 is arranged distanced from the board 21. Next, the arrangement of the press-fit terminals 20 provided in the case 11 will be described.

[0023] FIG 2 is a view of the mike module 10 shown in FIG 1 with the board removed. The press-fit terminals 20 are arranged in tandem from front to back on the left side of the case 11. Tip end portions of the press-fit terminals 20 are inserted into the through-holes, and press-fit connecting portions that are wider than the diameter of the through-holes are pressed into the through-holes. As a result, a contact load is produced, such that electrical and mechanical contact between the press-fit terminals 20 and the through-holes is obtained. Also, in this example embodiment, so-called needle-eye type press-fit terminals are arranged so as to flex in the width direction, so the tip ends of the press-fit terminals more easily fit into the through-holes in the board. Alternatively, press-fit terminals having an N, M, W, or other sectional shape may also be used. Also, in view of the mike wire, the press-fit terminals may be arranged in the center of the case or on the right side of the case.

[0024] FIG 3 is a view of a cover 30 that covers the front of the mike module 10 shown in FIG 1. The mike module 10 is a device that has an open portion (i.e., the front) and has a width of approximately several centimeters. Therefore, in an attempt to suppress deformation of the case 11 when mounting it to a vehicle, the strength of the mike module 10 is increased by providing a spacer 31 that has a length equivalent to the depth of the case, on the cover 30. Also, attaching pawls 32 for attaching the cover 30 to the case 11, and board holddowns 33, are provided on the back surface of the cover 30. The board holddowns 33 of the cover 30 support the board 21 from the upper surface of the board 21 when the board 21 is correctly attached to the case 11. Here, if the board 21 is incorrectly attached, the board holddowns 33 and the board 21 will interfere with each other so the cover 30 will not be able to be attached to the case 11, thus making it easy for a worker to see that there is a problem with the assembly.

[0025] FIG 4 is a view of the mike module 10 shown in FIG 1 with the cover 30 shown in FIG 3 attached. After the board 21 has been correctly assembled, the cover 30 covers the open portion of the case 11. Also, the swivel amount of the swivel mike 12 is restricted so that excessive tension is not applied to the mike wire 15, by providing a stopper protrusion on the cover 30 or the case 11 to restrict the amount of movement of an arm 14 provided on the swivel mike 12. Further, when mounting the swivel mike 12 to a vehicle, the mike module 10 is fixed, with the swivel amount defined and the mike pointing in the desired direction, by the arm 14 abutting on a protrusion on a mounting portion of the vehicle, not shown, and catching the case fixing pawls 22 in grooves in the mounting portion. Next, the board assembly method will be described.

[0026] FIGS. 5A to 5C illustrate the positional relationships of the board 21, the guide mechanism, and the support portions when assembling the board 21 to the case 11. First, the board 21 is pinched between the index finger and the thumb and inserted from the front opening of the case 11 until it presses against the back surface of the case 11. Then, when the board 21 is slid downward while remaining pressed against the back surface of the case 11, it moves forward along the inclined surfaces of the guides 17a and 17b arranged on the back surface. In this way, the board 21 is able to be positioned in the depth direction of the press-fit terminals 20 by the guides 17a and 17b. When the board 21 is slid further downward, it moves to the center along the inclined surfaces of the slides 18a and 18b arranged on the sides surfaces of the case, as shown in FIG 5 A. In this way, the board 21 is able to be positioned in the width direction of the press-fit terminals 20 by the slides 18a and 18b. As a result of the board 21 being positioned in both the depth direction and the width direction in this way, the tip ends of the press-fit terminals 20 slide into the through-holes in the board 21. At this time, the board 21 contacts the guide 17a and the slide 18a at the encircled portion Ca in the drawing, and contacts the guide 17b and the slide 18b at the encircled portion Cb in the drawing. That is, the board 21 is guided to the mating position with the conductive through-holes by contacting the guide mechanism in at least four locations.

[0027] Moreover, the board 21 is slid even further downward, it moves sliding on the guides 17a and 17b and the slides 18a and the 18b, such that the bulging portions (i.e., the press-fit connecting portions) of the press-fit terminals 20 are guided to the through-holes, as shown in FIG 5B.

[0028] Further, when the board 21 is slid all the way down to the bottom of the case 11 while being kept horizontal using a jig, the bulging portions (i.e., the press-fit connecting portions) of the press-fit terminals 20 engage with (i.e., fit into) the through-holes. Then, the board 21 comes away from the guides 17a and 17b and the slides 18a and 18b. At this time, the guides 17a and 17b and the slides 18a and 18b no longer guide the board 21 nor contact the board 21, but instead keep a fixed distance (i.e., clearance) from the board 21. Also, as shown in FIG 5C, the connection between the press-fit terminals 20 and the through holes is completed by the flange portions 19a and 19b of the case 11 supporting the board 21. At this time, neither the back nor the sides of the case 11 contact the board 21, so no force of any kind is applied to the board 21. Therefore, the attachment load is stable. Also, the slides 18a and 18b in the positions shown in FIG 5C act as stoppers that prevent the board 21 from coming out. Incidentally, the guides 17a and 17b and the slides 18a and 18b serve as the guide mechanism for leading the press-fit terminals 20 to the through-holes in the board 21. The dimensions of the guides 17 and the slides 18 are set taking variations in manufacturing, such as the tolerance levels of the case 11 and the board 21, sufficiently into account.

[0029] Next, a case in which the board 21 is assembled to the case 11 while being tilted by mistake will be described with reference to FIGS. 6A and 6B. FIGS. 6A and 6B are views of contact points of the support portions and the guide mechanism of the board assembly structure. As shown in FIG 6A, if the board 21 is tilted to the left 1468

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by mistake, as shown by the solid line, when the board 21 is pinched between fingers and moved downward, the board 21 will contact the case 11 at the encircled portions Ca, Cb, and Cc in FIG 6 A. Here, portion Cc contacts the front of the guide 17b, as shown in FIG 6B that is a top view, so clearance is assured between the back of the case 11 and the board 21. Therefore, even if the board 21 is tilted in this way, the through-holes 23 are still able to be aligned with the press-fit terminals 20 because the board 21 contacts the guide mechanism at three locations, i.e., the guide 17b and the slides 18a and 18b (i.e., portions Ca, Cb, and Cc).

[0030] Similarly, if the board 21 is tilted to the right, as shown by the broken line in FIG 6A, the through-holes 23 are still able to be aligned with the press-fit terminals 20 because the board 21 contacts the case 11 at three locations, i.e., the guide 17a and the slides 18a and 18b. Moreover, in this example embodiment, even if the through-holes 23 in the board 21 are offset from the tip ends of the press-fit terminals 20, this positional offset can be corrected by the elastically displacement of the tip ends of the press-fit terminals 20, so the tip ends of the press-fit terminals 20 will fit into the through-holes 23.

[0031] Thus, as described above, using the board assembly structure according to the example embodiment makes it possible to position the through-holes of the board in the depth direction and the width direction of the press-fit terminals of the case simply by moving the board against the back of the case when assembling the board to the case. As a result, assembly is possible without requiring a precise positioning mechanism. Furthermore, the board that is assembled in the case is supported a predetermined distance from the case (i.e., with a predetermined clearance between it and the case). Thus, the board can be retained without being subjected to excess stress such as stress from heat expansion.

[0032] Incidentally, this example embodiment describes one mode of a mike module, but the invention is not limited to this as long as the board is able to be guided to the position of the press-fit terminals. Also, the number and shapes of the guides may be selected as appropriate.

Claims

CLAIMS:

1. A board assembly structure comprising:

a case that includes an open portion, and inside of which a plurality of protruding terminals are provided;

a board that includes conductive through-holes into which the protruding terminals fit;

a support portion that is provided on a bottom surface of the case and supports the board; and

a guide mechanism that includes an inclined surface and is provided on an inside surface of the case,

wherein the guide mechanism guides the board that has been inserted into the case through the open portion of the case, such that the conductive through-holes engage with the protruding terminals, and then stops guiding the board before the board becomes supported by the support portion.

2. The board assembly structure according to claim 1, wherein the plurality of protruding terminals are press-fit terminals, and the protruding terminals of the case are electrically connected with the board by the through-holes of the board being fit together with the press-fit terminals.

3. The board assembly structure according to claim 1 or 2, wherein the plurality of protruding terminals are provided so as to protrude upward.

4. The board assembly structure according to any one of claims 1 to 3, wherein the guide mechanism is provided on a side surface of the case.

5. The board assembly structure according to claim 4, wherein the inclined surface of the guide mechanism is inclined in a height direction of the case.

6. The board assembly structure according to claims 4 or 5, wherein a distance between a lower end of the guide mechanism and an upper end of the support portion is greater than a thickness of the board.

7. The hoard assembly structure according to any one of claims 4 to 6, the guide mechanism includes a plurality of guide members, and the guide members are provided on two of the side surfaces that are parallel to each other.

8. The board assembly structure according to claim 7, wherein the open portion is formed on the side surface other than the two of side surfaces, and the guide mechanism includes the guide member that is provided on the side surface that faces the open portion.