JP2002216886A - On-vehicle electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an on-vehicle electronic device excellent in heat dissipation characteristic, waterproof characteristic, and anti-vibration characteristic, using small and a high-density electronic substrate. SOLUTION: A structure is constituted that a connection pin 22a inserted by pressing in a connector part of a connector housing 20 is soldered to an open sided free end 40a that is an one end of the electronic substrate 40, and an exothermic parts 41 are fixed in the other end. Under a face of an annular frame component 23, which is a part of connector housing 20, and is integrated in one, a base 10 by aluminum die-casting is fixed by adhesion fixation, and a generated heat of the exothermic parts 41 is heat-conducted to a heat conducting face 12. A cover 30 is fixed by adhesion fixation to the upper surface of the annular frame component 23. By bending distortion of the open-sided free end 40a of the electronic substrate 40, a height size error of right and left of the electronic substrate 40 and a stress of a soldering part by heat expansion of the connection pin 22a are absorbed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle electronic device, and more particularly, to heat resistance, water resistance (waterproofness),
The present invention relates to an on-vehicle electronic device structure including a storage case having excellent vibration resistance and mass productivity.

[0002]

2. Description of the Related Art In general, the simplest structure of a housing for a printed circuit board is a two-piece structure including a pair of a case member and a cover member, which is disclosed in Japanese Patent Application Laid-Open No. 8-148842 (prior art). 1), JP-A-11-
346418 (Prior Art 2).
Among them, Prior Art 2 does not discuss how to efficiently dissipate the heat generated by the heat-generating components attached to the electronic board. However, Prior Art 1 considers the heat-generating electronic components as insulated electronic circuit components, Is proposed to protect the electrical short circuit and improve the heat radiation effect by contacting the cover with a sheet metal cover. Prior Art 2 also discloses a structure in which a connector housing and a cover are integrated, and an electronic substrate is fixed to the cover.

A three-piece housing structure in which an upper and lower cover member is attached to an intermediate frame member to which a printed circuit board is fixed is disclosed in Japanese Patent Application Laid-Open Nos. Hei 6-318790 (Prior Art 3) and Japanese Patent Laid-Open No. Hei 8-181471. (Prior art 4)
Is disclosed. Prior Art 3 relates to sealing with an adhesive fixing material between the intermediate frame member and the upper and lower covers, but does not mention improvement in heat dissipation of the heat-generating component. Prior Art 4 discloses a structure in which a heat-generating component is pressed against an intermediate frame member by utilizing the elasticity of an electronic substrate to effectively dissipate heat.

On the other hand, according to JP-A-8-204072 (prior art 5), heat generated by a heat-generating component fixed to one surface of a double-sided substrate is transferred to the other surface through a plated through-hole. In addition, there has been proposed a concept of fixing to a part of a heat conductive case via a heat conductive elastic insulating sheet. JP-A-11-266078 (Prior Art 6) describes a method for manufacturing a multilayer board in which a filler is filled in through-hole plating holes of an electronic board and the filler is covered with a conductive layer. I have.

[0005]

As the size and density of electronic substrates increase, it becomes important to improve the heat dissipation of the heat-generating components. There is a demand for products that meet various requirements such as performance and mass productivity. However, in the prior art 1, there is a problem in that a structure in which an insulated electronic circuit component having poor heat conductivity is simply brought into contact with the cover, and sufficient heat conduction cannot be expected. Further, also in Prior Art 4, it is necessary to reduce the stress of the soldering portion of the heat-generating component, and there is a problem that the pressure-bonding force depending on the elasticity of the electronic substrate cannot be sufficiently increased. On the other hand, the heat dissipation structure according to Prior Art 5 does not show the entire structure of the housing, but has waterproofness, vibration resistance,
It was an unfinished technology to meet various requirements such as mass production.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a small, high-density electronic circuit board housing excellent in heat dissipation, vibration resistance, and mass productivity. It is intended to provide an in-vehicle electronic device including a storage housing structure system having excellent waterproofness, which can be installed outside a vehicle compartment.

[0007]

A vehicle-mounted electronic device according to the present invention has a connector portion into which a number of connection pins are press-fitted and a mating connector is inserted. The connection pins are soldered to one end and a heat-generating component is fixed to the other end. An electronic frame, an annular frame member integrally formed with the connector portion and surrounding the outer periphery of the electronic substrate, a base for closing a lower end of the annular frame member and dissipating heat generated by the heat generating component, A cover is attached and fixed to the upper end of the annular frame member while the electronic substrate is fixed, and a soldering position of the connection pin is a cantilever free end protruding from a fixing position of the electronic substrate.

Further, in the above-mentioned structure, the vehicle-mounted electronic device according to the present invention has a first annular groove provided on the outer periphery of the upper end of the base, and a lower end of the annular frame member which fits in the first annular groove. An annular projection provided, a second annular groove provided on an outer periphery of an upper end of the annular frame member, an outer peripheral bent portion of a cover fitted into the second annular groove, the first and second Each of the annular grooves is filled with a thermosetting adhesive, and the annular protrusion and the outer bent portion are fitted and heat-treated to integrate the base, the annular frame member, and the cover.

Further, the on-vehicle electronic device according to the present invention comprises:
In the above configuration, the connection pins of the connector section are divided into a plurality of groups, and a mating connector is inserted into each of the groups.

In addition to the above configuration, the on-vehicle electronic device according to the present invention, the mating connector has an annular groove fitted into an annular wall portion of each group of connection pins of the connector portion, and an inner groove of each group. It has an elastic packing interposed between it and the peripheral surface.

Further, the on-vehicle electronic device according to the present invention comprises:
In addition to the above configuration, a plurality of mounting holes are provided in the base, and the base is fastened and fixed to the vehicle body at the positions of the mounting holes.

[0012] In addition to the above configuration, the vehicle-mounted electronic device according to the present invention further includes a plating layer formed on the upper surface and the rear surface of the other end of the electronic board to which the heat-generating component is soldered. A through-hole plating hole that penetrates the substrate is provided, and heat generated by the heat-generating component fixed to the upper surface of the electronic substrate is transmitted to the base on the back surface side of the electronic substrate through the plating layer and the through-hole plating hole. The in-vehicle electronic device according to claim 1, wherein the electronic device is transmitted.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a top view of the on-vehicle electronic device, and FIG.
2 is a sectional view taken along the line II-II in FIG. 1, and FIG.
(A) is a partially enlarged view, FIG. 3 is a plan view of a base constituting the on-vehicle electronic device, FIG. 4 is an enlarged cross-sectional view of a connector portion of the on-vehicle electronic device, and FIG. ,
FIG. 5B is a plan view of a mounting portion of the heat-generating component.

In FIG. 1, reference numeral 10 denotes a base for mounting a cover for covering a connector housing (including a connector portion and an annular frame member), an electronic board, and equipment. It is conductive. 11a to 11d are base 1
Reference numeral 20 denotes a mounting hole in the vehicle body provided on each of four sides, reference numeral 20 denotes a connector housing into which a mating connector is inserted (a portion into which the mating connector is inserted is referred to as a connector portion);
Reference numerals a and 21b denote a part of the connector housing 20, and annular wall portions 22a and 22b provided so as to surround the connection pins divided into two groups for respectively connecting a plurality of mating connectors. Denotes a plurality of connection pins arranged side by side, 23 denotes a part of the connector housing 20, an annular frame member wrapped around the base 10, and 30 denotes a cover for covering an upper portion of the base 10, and the cover 30 is a sheet metal. And covers a portion of the base 10 other than a space for connecting a mating connector surrounded by the annular wall portions 21a and 21b.

The connector housing 20 is, for example, P
It is resin-molded with BT (polybutylene terephthalate) or the like. As described above, when the on-vehicle electronic device is observed from the upper surface, the rectangular connector housing 20 is formed.
The connection pins 21a and 21b are intermittently arranged along one side to form a connector connection portion, and the other portion is a portion where electronic components are arranged.

In the sectional view of FIG. 2A, reference numeral 40 denotes an electronic substrate on which electronic components are mounted. The electronic substrate 40 is made of a glass epoxy material, and a large number of electronic components are provided on the upper and lower surfaces thereof. Soldered. Reference numeral 12 denotes a heat transfer surface for releasing heat of the heat-generating component 41 mounted on the electronic substrate 40, 13 denotes a substrate fixing screw for fixing the electronic substrate 40 to the base, and 31 denotes an outer portion provided on an outer peripheral portion of the cover 30. The outer peripheral bent portion 31 is fitted into a groove formed in the annular frame member 23. Reference numeral 39 denotes a board pedestal portion for positioning when the electronic board 40 is soldered to the connector housing 20. Reference numeral 40a denotes a cantilever free end of the electronic board 40 into which the connection pins 22a are inserted. Reference numeral 40a is located in a region closer to the connection pin 22a than the position where the fixing screw 13 from the connection pin 22a is arranged, that is, in a region protruding from the fixing position of the electronic substrate 40.

Reference numeral 42 denotes an insulating sheet affixed to the back surface of the electronic board 40 below the heat-generating component 41. The electronic board 40 and the heat transfer surface 12 of the base 10 are in contact with each other via the insulating sheet 42. I have. The insulating sheet 42 is a heat conductive insulating sheet, and is a soft heat conductive insulating sheet made of a silicon material or the like. 50 is the connection pin 22
3A shows a mating connector connected to the connector housing 20 by being inserted into the connector housing 20.

Further, in FIG. 2 (b) showing a partially enlarged view of a portion 2b in FIG. 2 (a), reference numeral 14 denotes a first annular groove provided on the outer periphery of the base 10, and an annular shape of the connector housing 20. It fits with an annular projection 23b provided on the outer periphery of the lower end of the frame member 23. Reference numeral 23a denotes a second annular groove provided on the outer periphery of the upper end of the annular frame member 23. The second annular groove 23a has an outer peripheral bent portion 31 of the cover 30.
Are fitted.

In the on-vehicle electronic device thus configured, a large number of connection pins 22a and 22b are soldered to one end (a portion corresponding to the cantilever free end 40a) of the electronic board 40. Are the screw holes 13a to 13 in FIG.
It corresponds to a cantilever free end 40a protruding from the cantilever end connecting c, and the cantilever free end 40a has flexibility and can reduce stress by bending.

In FIG. 4 which is an enlarged view of the connector portion shown in FIG. 2A, reference numeral 50 denotes annular wall portions 21a and 21b.
A number of female pins (not shown) are inserted into the mating connector, and are configured to be in contact with the connection pins 22a and 22b. Further, in FIG.
The annular groove 51 is formed so as to sandwich the annular walls 21a and 21b, and an elastic packing 52 made of, for example, a rubber material is mounted on an inner peripheral surface thereof.

FIGS. 5 (a) and 5 (b) are detailed views of the mounting of the heat-generating component 41. In this figure, reference numeral 41a denotes a heat-radiating electrode provided on the heat-generating component 41, which is wide over substantially the entire surface of the heat-generating component 41. Area. Symbols 44a, 4
4b is a copper foil pattern to which electrodes are connected, 43a to 43c
Is a large number of through-hole plated holes provided in the electronic board 40; 45a, 45b are first plating layers, for example, copper plating, which connect the copper foil patterns 44a, 44b;
46b is a solder resist layer, 47a to 47i are fillers filled in the through-hole plating holes 43a to 43i, for example, epoxy resin, and 48a, 48b are second plating layers (plating) formed by, for example, copper plating for sealing the fillers. , 49a is a solder layer for the heat radiation electrode 41a.

Next, an example of the manufacturing process of the on-vehicle electronic device including the manufacturing process of the through-hole plated holes 43a to 43c as shown in FIG. First, copper foil patterns 44a and 44b are formed on the upper and lower surfaces of the electronic substrate 40, respectively. A through hole is opened in the electronic substrate 40. next,
First plating layers 45a to 45c are formed on the upper surface, the back surface, and the inside of the through hole of the electronic substrate 40 by copper plating. Filler 47 is provided in plated through holes 43a to 43c.
a to 47i are filled. Then, the second plating layer 48
a and 48b are formed and patterned. Electronic substrate 40
Resist layers 46a and 46b are formed on the upper and lower surfaces of the substrate. Electronic components are mounted on the upper and lower surfaces of the electronic substrate 40.
The heat-generating component 4 is provided on the upper surface of the electronic substrate 40 via the solder layer 49a.
Fix 1 The electronic board 40 is mounted by the protrusion of the joint portion 39 of the connector housing 20, and
The connection pins 22a and 22b are inserted into the cantilever free end 40a, and soldered using a jet soldering device or the like.

The second plating layer 48 on the back surface of the electronic substrate 40
b. An insulating sheet 42 is attached on b. Then, base 1
For example, after injecting, for example, a silicon-based thermosetting adhesive into the first annular groove 14 of FIG. From the part where the cover 30 is covered)
The back side of the electronic substrate 40 is fixed to the base 10 by screwing (with the substrate fixing screw 13) (the structure of the cantilever free end 40a of the electronic substrate 40 is obtained, and the base 10 and the insulating sheet 42 are in close contact with each other). . In addition, it is also possible to use a heat transfer insulating adhesive instead of the heat transfer insulating sheet 42.

After injecting, for example, a silicon-based thermosetting adhesive into the second annular groove 23a of the electronic substrate 40, the cover 30 is put on the open portion on the upper surface side of the electronic substrate 40 and dried by heating. As a result, the base 10, the connector housing 20, and the cover 30 are integrated, and an in-vehicle electronic device in which electronic components are sealed is obtained. The in-vehicle electronic device is fastened and fixed to the vehicle body with fixing screws or the like at positions of the mounting holes 11a to 11d provided in the base 40.

In the above-described assembling process, when the electronic board 40 is fastened and fixed to the base 10 with a large number of screws 13, there is a slight gap between the contact surface between the base 10 and the annular frame member 23 due to the dimensional tolerance of each part. The parent dimension is determined so as to occur, but in this case, the adhesive injected into the first annular groove 14 is pushed out by the annular projection 23b, and it is considered that the gap is filled. Water resistance and mechanical strength after heating and drying are ensured.

In the event that the electronic substrate 40 is fastened and fixed to the base 10 with a large number of substrate fixing screws 13, if the contact surfaces of the base 10 and the annular frame member 23 come into close contact due to variations in dimensional tolerances of the respective components. In such a case, the cantilevered free end 40a of the electronic substrate 40 is bent and the connection pin 2
Care is taken not to apply excessive stress to the soldered portions 2a and 22b. When mounting the finished product on the vehicle body, the base 10 having high mechanical strength and heavy weight is tightened and fixed at the mounting holes 11a to 11d,
The mating connector 50 is inserted into the annular wall portions 21a and 21b to be used.

According to such an in-vehicle electronic device, the stress on the soldering portion due to the integration of the connector housing 20 including the annular frame member 23 and the base 10 via the electronic substrate 40 is reduced. Then, the electronic substrate 40 is securely fixed to the base 10 and
Of heat generated in the electronic circuit board 40, and the stress on the soldering portion is reduced by the bending of the cantilever free end 40a of the electronic substrate 40 even when the connection pins 22a and 22b expand and contract due to a temperature change. There is.

In addition, as the connector housing 20 including the annular frame member 23 and the base 10 are integrated via the electronic board 40, there is a slight difference between the annular frame member 23 and the base 10 due to the variation in dimensional tolerance of each component. Even if a gap occurs, there is an effect that both can be securely bonded and fixed to ensure waterproofness and mechanical strength. Further, as described above, when the electronic substrate 40 is fastened and fixed to the base 10 with a large number of screws 13, even when the contact surface between the base 10 and the annular frame 23 comes into close contact due to the variation in dimensional tolerance of each part, the electronic substrate 40 40 cantilever free ends 40
There is an effect that it is possible to prevent a stress from being applied to the soldered portions of the connection pins 22a and 22b due to the bending of a.

The connector housings 20 are divided into a plurality of groups, and the mating connectors 50 which are press-fitted into the respective connector housings 20 have annular grooves 51 which fit into the annular walls 21a, 21b of the respective connector housings 20, and respective connectors. An elastic packing 52 is provided between the housing 20 and the inner peripheral surface. Therefore, the external force accompanying the attachment / detachment of the mating connector 50 can be reduced and dispersed.
There is an effect that the waterproofness of the connector portion can be secured.

Further, the base 10 is provided with a plurality of mounting holes 11a to 11d.
It is configured to be fixed to the vehicle body via 1d. Therefore, by mounting and fixing the whole product via the base 10 which is a weight body, there is an effect that it is possible to prevent an excessive vibration load from being applied to the electronic board 40 and the connector housing 20.

The second plating layers 48a and 48b prevent solder from flowing into the through-hole plating holes 43a to 43c, secure a contact surface with the heat transfer surface, and form a large number of through-hole plating holes 43a. 43c to improve the thermal conductivity, it is possible to prevent a decrease in the area of the heat conductive contact surface, and as a result, it is possible to reduce an increase in the temperature of the heat generating component 41.

Embodiment 2 In the above example, the connection pin 2
2a and 22b extend in a direction perpendicular to the electronic board 40, and the mating connector 50 is also inserted from the extension line direction. However, as shown in the cross section of the connector portion in FIG. 6, the connection pins 22aa are bent in advance to the outside of the electronic board 40 at an angle of 90 °, and the mating connector 50 is connected to the connector housing 20a. It is also possible to adopt a structure in which press-fitting is performed in the parallel line direction.
Even in this case, even if stress is applied to the soldering portion for fixing the connection pin 22aa and the electronic board 40 by press fitting, since this soldering portion is located at the cantilever free end 40a of the electronic board 40, the stress is reduced. Can be eased.

[0033]

According to the present invention, since one end of the electronic board to which the connection pins are soldered is a cantilever free end, the stress generated when the mating connector is inserted into the connector, or Stress caused by dimensional tolerances of members, stress due to temperature change, and the like can be reduced by bending of the electronic substrate, and the vibration resistance of the vehicle-mounted electronic device can be improved.

Further, according to the present invention, the base, the annular frame member and the cover are adhered to each other by using a thermosetting adhesive to obtain an integrated and sealed housing, so that the waterproofness of the on-vehicle electronic device can be improved. Can be improved.

Further, according to the present invention, the connection pins of the connector portion are divided into a plurality of groups, and the mating connector is inserted into each of the groups. By reducing the dispersion, the vibration resistance of the in-vehicle electronic device can be improved.

Further, according to the present invention, the mating connector has an elastic packing interposed between the annular groove fitted into the annular wall of each group of the connection pins of the connector and the inner peripheral surface of each group. Therefore, it is possible to obtain an in-vehicle electronic device capable of improving waterproofness at a fitting portion between a mating connector and a connector portion.

Further, according to the present invention, the base is provided with a plurality of mounting holes. At the positions of the mounting holes, the base, which is a heavy body, is fixed to the vehicle body in order to tighten and fix the base to the vehicle body. Thus, it is possible to suppress an excessive vibration load from being applied to other members constituting the vehicle-mounted electronic device, and it is possible to improve the durability of the vehicle-mounted electronic device.

According to the present invention, a plating layer is formed on each of the upper surface and the rear surface of the other end of the electronic board to which the heat-generating component is to be soldered, and a through-hole plating hole penetrating the electronic board is provided. Through the plating layer and the through-hole plating holes, the heat generated by the heat-generating component fixed to the upper surface of the electronic board is configured to be transmitted to the base on the back side of the electronic board,
The plating layer prevents the solder for fixing the components from flowing into the through-hole plating holes, secures a contact plane between the heat-generating components and the heat transfer surface, and has a structure where the through-hole plating holes and the plating layer are in contact. Since a wider heat conduction contact surface area can be ensured, a rise in temperature of the heat-generating component can be reduced.

[Brief description of the drawings]

FIG. 1 is a top view of an in-vehicle electronic device according to Embodiment 1 of the present invention.

FIG. 2 is a cross-sectional view and a partially enlarged view of the on-vehicle electronic device according to the first embodiment of the present invention, taken along line II-II of FIG. 1;

FIG. 3 is a plan view of the on-vehicle electronic device according to the first embodiment of the present invention, taken along line III-III of FIG. 2;

FIG. 4 is a sectional view of a connector portion of the vehicle-mounted electronic device according to the first embodiment of the present invention.

FIG. 5 is a cross-sectional view and a plan view of a heat-generating component mounting portion of the vehicle-mounted electronic device according to the first embodiment of the present invention.

FIG. 6 is a cross-sectional view of a connector portion of a vehicle-mounted electronic device according to a second embodiment of the present invention.

[Explanation of symbols]

10. Bases 11a to 11d. Mounting holes 12. Heat transfer surface 13. Board fixing screws 13a to 13e. Screw holes 14. First annular grooves 20, 20a. Connector housings 21a, 21b.
Connection Pin 23. Annular Frame Member 23a. Second Annular Groove 23b. Annular Projection 30. Cover 31. Outer Bend 39. Substrate Base 40. Electronic Substrate 40a. Free end 41. Heat generating component 41a. Heat radiation electrode 42. Insulating sheet 43a to 43c. Through hole plating hole 44a, 44b. Copper foil pattern 45a, 45b. First plating layer 46a, 46b. Solder resist layer 47a to 47i. Material 48a, 48b. Second plating layer 49a. Solder layer 5
0. Mating connector 51. Annular groove 52. Elastic packing.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 7/14 H05K 7/14 C 7/20 7/20 B F term (Reference) 4E360 AB13 AB31 CA02 CA03 EA03 ED02 ED07 GA24 GA28 GA29 GB99 GC03 GC08 GC13 5E087 EE02 EE11 EE14 FF03 GG01 HH01 HH02 LL02 LL12 MM08 QQ04 RR12 RR15 5E322 AA03 AA11 AB02 AB07 AB08 5E348 AA03 AA06 AA08 AA32

Claims (6)

[Claims] 1. A connector part into which a number of connection pins are press-fitted and a mating connector is inserted, an electronic board having one end soldered with the connection pins and the other end fixed with a heat-generating component, and integrally formed with the connector part. An annular frame member surrounding the outer periphery of the electronic substrate, a base for closing and lowering a lower end of the annular frame member and dissipating heat generated by the heat-generating component, and a base for fixing the electronic substrate to the base; An in-vehicle electronic device comprising a cover attached and fixed to an upper end, wherein a soldering position of the connection pin is a cantilevered free end protruding from a fixing position of the electronic board. 2. A first annular groove provided on an outer periphery of an upper end of a base, an annular protrusion fitted on the first annular groove and provided on a lower end of an annular frame member, and an outer periphery of an upper end of the annular frame member. The provided second annular groove, provided with an outer peripheral bent portion of a cover that fits in the second annular groove, after filling the first, second annular groove with a thermosetting adhesive respectively. The on-vehicle electronic device according to claim 1, wherein the base, the ring-shaped frame member, and the cover are integrated with each other by fitting the ring-shaped protrusion and the outer bent portion to each other and performing heat treatment. 3. The on-vehicle electronic device according to claim 1, wherein the connection pins of the connector section are divided into a plurality of groups, and mating connectors are inserted into each of the groups. 4. The mating connector has an annular groove fitted into an annular wall of each group of connection pins of the connector section and an elastic packing interposed between inner peripheral surfaces of each group. The on-vehicle electronic device according to claim 3, wherein 5. The on-vehicle electronic device according to claim 1, wherein the base is provided with a plurality of mounting holes, and the base is fastened and fixed to the vehicle body at the positions of the mounting holes. 6. A plating layer is formed on the upper surface and the back surface of the other end of the electronic board to which the heat-generating component is to be soldered, and a through-hole plating hole penetrating the electronic board is provided. 2. The vehicle-mounted electronic device according to claim 1, wherein heat generated by the heat-generating component fixed to the upper surface of the electronic substrate is transmitted to the base on the back surface side of the electronic substrate via the through-hole plating hole. 3. .