JP2020108056A - Antenna device - Google Patents

Abstract

To provide an antenna device capable of effectively protecting a circuit board provided in a case and increasing the strength of an antenna installation portion.SOLUTION: A circuit board 10 is housed inside an upper case 3 and a lower case 4 made of synthetic resin. An inner member 30 made of synthetic resin is provided above the circuit board 10 inside a storage space 5 of the upper case 3, and the inner member 30 protects an electronic component mounted on the circuit board 10. A first antenna 21 forming the antenna element 20 is installed on the outer surface 33 of the inner member 30, and the first antenna 21 is electrically connected to the electrode portion of the circuit board 10. The circuit board 10 is arranged within the range of the width dimension ha in the height direction of the element surface of the antenna element 20.SELECTED DRAWING: Figure 9

Description

The present invention relates to an antenna device mainly used for mounting on a vehicle.

Patent Document 1 describes an invention relating to a keyless entry receiver.
This keyless entry receiver has an upper case and a lower case both made of a synthetic resin material, and an antenna having a predetermined pattern is integrally formed on the inner wall surface of the upper case. A printed circuit board is housed inside the upper case and the lower case, an electrode is provided on the surface of the printed circuit board, and an end of the antenna and the electrode are in contact with each other for electrical conduction.

Patent Document 2 describes an invention relating to a roof module.
In this roof module, a base and a cover forming a housing are made of a synthetic resin material, and an antenna, a metal panel, and a module substrate are housed inside the housing. The antenna is a plane antenna, and an antenna pattern is formed on the surface of an insulating substrate by a printed circuit body. Electronic components are mounted on the module substrate. The metal panel is a plate made of silver, copper, aluminum, or the like, and is provided between the antenna and the module substrate to exert a shielding effect.

Patent Document 3 describes an invention relating to an antenna system.
In this antenna system, electronic components constituting a transceiver are mounted on the upper surface of a substrate. A protective member that covers the electronic component is installed on the substrate, and an antenna is formed on the outer surface of the protective member.

JP, 2005-45625, A JP, 2017-200806, A Japanese Patent No. 6365676

Since the keyless entry receiver described in Patent Document 1 has a structure in which the antenna is integrally formed on the inner wall surface of the upper case, the structure of the upper case becomes complicated and the manufacturing cost of the upper case increases. In addition, since the printed circuit board has a structure in which it is housed in an upper case and a lower case made of a synthetic resin material, the printed circuit board has low strength as a whole and has a drawback that the internal circuit is easily broken by a large external force.

In the roof module described in Patent Document 2, since the antenna, the metal panel, and the module substrate are housed as independent components inside the housing, the total number of components is large. In addition, the housing is made of a synthetic resin material and has low strength, and the antenna located inside the housing is also low in strength because it is a planar antenna having an antenna pattern formed on the surface of the insulating substrate. Therefore, the strength is low as a whole, and when used as an emergency notification system such as a TCU (Telematics Control Unit), the planar antenna and the internal circuit may be damaged when a vehicle accident occurs.

Since the antenna system in Patent Document 3 has a structure in which the antenna is formed on the outer surface of the protective member, the antenna is easily damaged by an external force, and it is difficult to use the antenna system in an emergency notification system or the like.

The present invention is to solve the above-mentioned conventional problems, and it is an object of the present invention to provide an antenna device that can be increased in strength as a whole, can be increased in strength of a supporting portion of an antenna, and can be easily assembled. There is.

The present invention is an antenna device in which a circuit board on which electronic components are mounted and an antenna for communication with the outside are housed inside a case made of synthetic resin,
Inside the case, the width dimension is larger than the distance between a pair of opposing sides of the circuit board in at least one direction, and the dimension in the height direction that is the board thickness direction of the circuit board is the board thickness of the circuit board. There is an inner member made of synthetic resin that is larger than the dimensions,
The circuit board is supported by the inner member, and an antenna element is fixed to the inner member.

In the antenna device of the present invention, it is preferable that the circuit board is housed in the inner member within the range of the dimension of the inner member in the height direction.

In the antenna device of the present invention, the element surface of the antenna element is oriented in a direction intersecting with the board surface of the circuit board, and the circuit board is positioned within the range of the dimension in the height direction of the element surface. Preferably.

In the antenna device of the present invention, it is preferable that the antenna element is fixed to an outer surface of the inner member extending in the height direction.

In the antenna device of the present invention, the antenna element has a joint portion parallel to the substrate surface of the circuit board, an electrode portion is provided on the substrate surface, and the contact portion is brought into pressure contact with the electrode portion. The mechanism can be configured as provided.

In the antenna device of the present invention, for example, the pressure contact mechanism is a screw member that passes through the joint portion and the electrode portion and fastens a part of the circuit board and a part of the case.

The antenna device of the present invention, at least one of a recessed portion that is recessed in the height direction and a hole portion that penetrates in the height direction is formed in the inner member, and the electronic component mounted on the circuit board is, It is located inside at least one of the recess and the hole.

In the antenna device of the present invention, it is preferable that the circuit board be sandwiched by a plurality of inner members inside the case from above and below in the height direction.

Since the antenna device of the present invention is provided with the inner member having the width dimension larger than the circuit board and the height dimension larger than the board thickness dimension of the circuit board in at least one direction, the circuit board is supported by the inner member. The circuit board can be protected when an external force is applied. Moreover, since the antenna element is fixed to the inner member, the strength of fixing the antenna can be increased by increasing the strength of the inner member. According to the present invention, since the inner member functions as a protective member or a reinforcing member that supports the circuit board, and further functions as an antenna support, the number of parts can be reduced and the assembling work is easy.

In particular, by fixing the antenna element to the outer surface of the inner member and arranging the circuit board within the dimension of the height direction of the antenna element, sufficient strength is ensured by the inner member, and the antenna device is further provided. Can be made thin.

The perspective view which shows the whole structure of the antenna device of embodiment of this invention, An exploded perspective view of the antenna device shown in FIG. Sectional drawing which cut|disconnected the antenna device shown in FIG. 1 by the III-III line, Sectional drawing which cut|disconnected the antenna apparatus shown in FIG. 1 by the IV-IV line, An enlarged exploded perspective view showing an enlarged view of a portion of the antenna device shown in FIG. 2 is a partially enlarged perspective view showing a part of the constituent members of the V arrow portion shown in FIG. 2, an enlarged exploded perspective view in which constituent members other than a circuit board and an antenna element are omitted in a portion indicated by an arrow V in FIG. An exploded perspective view of the antenna device shown in FIG. 5 taken along line VIII-VIII, Sectional drawing which shows the cut surface which cut|disconnected the state which the antenna device was assembled by the surface containing the VIII-VIII line,

FIG. 1 shows an antenna device 1 according to an embodiment of the present invention. As shown in FIG. 2, the antenna device 1 includes a circuit board 10 on which electronic components are mounted and a plurality of antenna elements 20.
In the antenna device 1 of the embodiment, a communication device is configured by the electronic components mounted on the circuit board 10 and the antenna element 20, and the antenna device 1 can independently communicate with the outside. Alternatively, the antenna device 1 of the present invention may communicate with the outside in cooperation with a separately provided communication device without constituting a communication device by itself.

The antenna device 1 of the embodiment is mounted on a vehicle, and various communication such as wireless WAN, wireless LAN, satellite positioning system, wireless communication for mobile phones, satellite communication and the like is performed using a plurality of antenna elements 20. Further, the circuit board 10 is equipped with an emergency notification system such as a TCU (Telematics Control Unit) and an eCall. Therefore, it is required to have strength that is not damaged when an external force or impact is applied by a vehicle accident or the like.

In the antenna device 1, the Z direction is the height direction, the X direction is the horizontal width direction, and the Y direction is the vertical width direction in orthogonal coordinates. As shown in FIG. 1, the antenna device 1 has a case 2. Case 2 has dimensions in the horizontal width direction (X direction) and vertical width direction (Y direction) that are larger than those in the height direction (Z direction), and the vertical width direction (Y direction) is in the horizontal width direction (X direction). ) Is larger than the size. As shown in FIG. 2, the case 2 has an upper case 3 and a lower case 4, both of which are made of synthetic resin.

As shown in the cross-sectional views of FIGS. 3 and 4, the upper case 3 has a cubic box shape and has a storage space 5 inside. The lower case 4 is inserted into the lower part of the storage space 5 of the upper case 3 so that the upper case 3 and the lower case 4 are combined. As shown in FIG. 2, fixing holes 4b are opened in a plurality of places in the lower case 4, and through holes 10b are formed in the circuit board 10 at positions corresponding to the fixing holes 4b. As shown in FIG. 3, inside the upper case 3, a plurality of fixing bosses 3b projecting downward toward the storage space 5 are integrally formed. As shown in FIG. 3, inside the storage space 5, the circuit board 10 is sandwiched between the lower case 4 and the fixing boss 3b, and the fixing screw 6 is inserted into the fixing hole 4b of the lower case 4, and the fixing is performed. The screw 6 passes through the through hole 10b of the circuit board 10 and is screwed into the female screw hole 3c formed in the fixing boss 3b of the upper case 3. As a result, the circuit board 10 is sandwiched between the upper case 3 and the lower case 4 and fixed inside the storage space 5.

As shown in FIG. 2, fixing protrusions 3a are integrally formed at four corners of the upper case 3, and fixing protrusions 4a are also integrally formed at four corners of the lower case 4. Has been done. The internal structure of the fixing protrusion 3a of the upper case 3 is a recess having an opening facing downward, and as shown in FIGS. 1, 3 and 4, the upper case 3 and the lower case 4 are combined. When they are fixed to each other, the fixing protrusion 4a of the lower case 4 is fitted into the recess of the fixing protrusion 3a of the upper case 3. The antenna device 1 is mounted on the vehicle by screwing the fixing protrusions 3a and 4a to a part of the vehicle body.

As shown in FIG. 2, a plurality of large electronic components 11 and 12 and small electronic components 13 are mounted on the upper surface of the circuit board 10 facing upward in the drawing. A connector 14 is fixed to the circuit board 10. A cutout portion 3g is formed on one side surface of the upper case 3, and as shown in FIG. 1, when the circuit board 10 is housed inside the case 2, the connector 14 moves outward from the cutout portion 3g. Project toward.

As shown in FIG. 2, the inner member 30 is housed between the circuit board 10 and the ceiling of the upper case 3. The inner member 30 is made of synthetic resin. The inner member 30 and the case 2 are made of a synthetic resin material having a thermal conductivity higher than that of air so that heat generated from various electronic components housed inside the case 2 can be effectively released to the outside of the case 2. It is preferably formed. For example, the inner member 30 and the case 2 are made of an epoxy resin material.

As shown in FIGS. 3 and 4, the inner member 30 is housed in the housing space 5 of the upper case 3 and sandwiched between the ceiling portion of the upper case 3 and the circuit board 10. As shown in FIG. 2, the inner member 30 is formed with a plurality of fitting holes 30a penetrating in the height direction (Z direction). The upper case 3 is integrally formed with the plurality of fixing bosses 3b shown in FIG. 3 projecting downward toward the storage space 5 and the plurality of fixing bosses 3d shown in FIG. The bosses 3b and 3d are inserted into the fitting holes 30a, and the inner member 30 is positioned and housed inside the upper case 3.

As shown in FIG. 3, the dimension H of the inner member 30 in the height direction (Z direction) is sufficiently larger than the plate thickness dimension of the circuit board 10 in the height direction (Z direction). It is accommodated within the range of the height dimension H of the inner member 30. As shown in FIG. 3, the width dimension X30 of the inner member 30 in the lateral width direction (X direction) is larger than the distance X10 between the pair of sides 17, 17 facing each other in the lateral width direction (X direction) of the circuit board 10. As shown in FIG. 4, the width dimension Y30 of the inner member 30 in the vertical width direction (Y direction) is larger than the distance Y10 between the pair of sides 18, 18 facing each other in the vertical width direction (Y direction) of the circuit board 10. Is getting bigger. In the present invention, at least one of the width dimensions X30 and Y30 is larger than the distance X10 or the distance Y10. That is, in at least one direction, the width dimension of the inner member 30 in the same direction is larger than the distance between the pair of opposing sides of the circuit board 10.

As shown in FIGS. 2, 3 and 4, the inner member 30 is formed with a hole portion 31 penetrating in the height direction and a concave portion 32 opened downward. In a state where the antenna device 1 is assembled, the large electronic components 11 and 12 mounted on the circuit board 10 are housed inside the hole portion 31, and the small electronic component 13 mounted on the circuit board 10 is located in the recess 32. It is housed inside. In the present invention, at least one of the hole 31 and the recess 32 is formed in the inner member 30, the electronic component is located inside the hole 31 or the recess 32, and the electronic component is protected by the inner member 30. That is, at least one of the concave portion 32 recessed in the height direction and the hole portion 31 penetrating in the height direction is formed in the inner member 30, and the electronic component mounted on the circuit board 10 has the concave portion and the hole portion. It is a structure located inside at least one side.

The inner member 30 has a dimension H in the height direction larger than the plate thickness dimension of the circuit board 10, and the width dimension of the inner member 30 in the same direction is greater than the distance between a pair of opposing sides of the circuit board 10 in at least one direction. Is bigger. Then, at least one of the concave portion 32 recessed in the height direction and the hole portion 31 penetrating in the height direction is formed in the inner member 30, and the electronic component mounted on the circuit board 10 includes the concave portion 32 and the hole portion. It is located inside at least one of 31. Therefore, the circuit board 10 and the electronic components 11, 12, and 13 can be held by the inner member 30, and even if the case 2 is made of synthetic resin, the overall strength can be maintained high and a large impact such as a vehicle collision accident is given. However, it is possible to protect the internal circuit. Further, by forming the inner member 30 and the case 2 with a synthetic resin material having a higher thermal conductivity than air, it is possible to dissipate the heat generated from the electronic component.

As shown in FIG. 2, a lower inner member 40 is provided between the bottom of the lower case 4 and the circuit board 10. The lower inner member 40 is made of the same synthetic resin material as the inner member 30. As shown in FIG. 2, a ridge 41 protruding in the height direction (Z direction) is integrally formed on the upper surface of the lower inner member 40. As shown in FIGS. The substrate 10 is supported from below by the raised portion 41. By providing the lower inner member 40 together with the inner member 30 and sandwiching the circuit board 10 between the inner member 30 and the lower inner member 40 from above and below, the circuit board 10 and the electronic components 11, 12, and 13 are further protected from external impact. become able to.

As shown in FIG. 2, the inner member 30 has two outer side surfaces 33, 33 oriented in the lateral width direction (X direction) and two outer side surfaces 33, 33 oriented in the longitudinal width direction (Y direction). One set of antenna elements 20 is fixed to each outer surface 33. 5 to 9 show the details of the mounting structure of the pair of antenna elements 20 provided in the V arrow portion of FIG. The mounting structure of the antenna element 20 on the other three outer surfaces 33 is the same as the mounting structure of the antenna element 20 shown by the arrow V.

As shown in FIGS. 5 to 7, one set of antenna elements 20 has a first antenna 21 and a second antenna 22. The first antenna 21 and the second antenna 22 are formed by superposing nickel plating and gold plating on the surface of a conductive metal plate. The element surfaces of the first antenna 21 and the second antenna 22 are arranged in parallel with the XZ plane that intersects (is orthogonal to) the substrate surface of the circuit substrate 10. The element surface of the first antenna 21 has a meandering shape. A joint 21a bent at a right angle in the Y direction is formed in a part of the first antenna 21, and a hole 21b is formed in the joint 21a. The element surface of the second antenna 22 is square. A joint 22a bent at a right angle in the Y direction is formed in a part of the second antenna 22, and a hole 22b is formed in the joint 22a.

As shown in FIG. 5, a first installation recess 34a and a second installation recess 34b are formed on the outer surface 33 of the inner member 30. As shown in FIG. 6, the first antenna 21 is installed such that the element surface is in close contact with the surface of the first installation recess 34a, and the second antenna 22 is that the element surface is in close contact with the surface of the second installation recess 34b. Is installed. Preferably, the first antenna 21 is adhered and fixed to the surface of the first installation recess 34a, and the second antenna 22 is adhered and fixed to the surface of the second installation recess 34b.

8 and 9, the fixing boss 3d integrally formed downward from the ceiling portion of the upper case 3 toward the storage space 5 is shown in an enlarged manner. The fixing boss 3d is the same as that shown in the sectional view of FIG. A small diameter portion 3e is formed at the lower end of the fixed boss 3d, and a female screw hole 3f is formed at the center of the fixed boss 3d. By inserting the fixing boss 3d into the fitting hole 30a formed in the inner member 30, the inner member 30 is positioned in the storage space 5 of the upper case 3.

As shown in FIGS. 7 to 9, the circuit board 10 is formed with a hole 15 penetrating in the height direction (Z direction), and the board surface of the circuit board 10 surrounds the hole 15. A ring-shaped electrode portion 16 is formed. The electrode portion 16 is a part of the wiring pattern formed on the surface of the substrate and is made of copper foil or the like. The joint portion 21a formed on the first antenna 21 and the joint portion 22a formed on the second antenna 22 are placed so as to overlap with the respective electrode portions 16 on the surface of the substrate. As shown in FIG. 9, the lower end surface of the fixed boss 3d formed on the upper case 3 is installed on the upper surfaces of the joints 21a and 22a of the respective antennas 21 and 22, and the small diameter portion 3e of the lower end of the fixed boss 3d is provided. , The holes 21b and 22b formed in the joints 21a and 22a and the holes 15 and 15 formed in the circuit board 10.

As shown in FIG. 8 and FIG. 9, the washer 24 is installed on the lower surface of the circuit board 10, and the screw member 25 constituting the press contact mechanism is inserted into the washer 24 and screwed into the female screw hole 3f of the fixing boss 3d. Has been done. Due to the tightening force of the screw member 25, the circuit board 10 is sandwiched between the screw member 25 and the washer 24 and the fixing boss 3d of the upper case 3, and the circuit board 10 is supported by the inner member 30. Further, the joint portions 21a and 22a of the respective antennas 21 and 22 and the electrode portion 16 are pressed into contact with each other to be electrically connected, and the antennas 21 and 22 are electrically connected to the electronic circuit mounted on the circuit board 10. As shown in FIG. 9, the small-diameter portion 3e at the lower end of the fixing boss 3d is inserted into the holes 21b and 22b of the joints 21a and 22a and the hole 15 of the circuit board 10. The member 25 does not touch the antennas 21 and 22 and the electrode portion 16.

Since the first antenna 21 and the second antenna 22 forming the antenna element 20 are fixed to the outer surface 33 of the inner member 30 that functions as a protective member or a reinforcing member, a shock or a large force is applied from the outside. Even if it is damaged, the antenna element 20 is less likely to be damaged. Further, as shown in FIGS. 8 and 9, the width dimension ha of the element surface of the first antenna 21 in the height direction (Z direction) is substantially equal to the width dimension of the height dimension of the outer surface 33 of the inner member 30. Therefore, the antenna element 20 can be installed by effectively utilizing the outer surface 33 of the inner member 30. Further, since the circuit board 10 is accommodated within the range of the width dimension ha of the element surface of the first antenna 21 in the height direction (Z direction), the element surface of the antenna element 20 can be secured wide, and the antenna device is also provided. It is possible to reduce the thickness of the entire No. 1 device.

In the antenna device 1 of the embodiment, the circuit board 10 and the antenna element 20 are housed inside the case 2 made of synthetic resin, but the inner member 30 housed in the housing space 5 inside the case 2 allows the circuit board 10 to be mounted on the circuit board 10. Since the mounted electronic components 11, 12, 13 are protected and the antenna element 20 is fixed to the inner member 30, the strength is high and each component can be effectively housed in the case.

In the above-described embodiment, the first antenna 21 and the second antenna 22 that form the antenna element 20 are formed of a sheet metal material, but each antenna has a copper foil, a conductive material, and a conductive material on the outer surface 33 of the inner member 30. It may be pattern-formed with a paint, a vapor deposition film, or the like.

DESCRIPTION OF SYMBOLS 1 Antenna device 2 Case 3 Upper case 3b, 3d Fixing boss 4 Lower case 10 Circuit board 11, 12, 13 Electronic component 15 Hole part 16 Electrode part 17, 18 sides 20 Antenna element 21 First antenna 21a Joint part 21b Hole part 22 2nd antenna 22a Joint part 22b Hole 25 Screw member (press-contact mechanism)
30 Inner Member 31 Hole 32 Recess 33 Outer Side 40 Lower Inner Member

Claims (8)

In an antenna device in which a circuit board on which electronic components are mounted and an antenna for communication with the outside are housed inside a case made of synthetic resin,
Inside the case, the width dimension is larger than the distance between a pair of opposing sides of the circuit board in at least one direction, and the dimension in the height direction that is the board thickness direction of the circuit board is the board thickness of the circuit board. There is an inner member made of synthetic resin that is larger than the dimensions,
An antenna device, wherein the circuit board is supported by the inner member, and an antenna element is fixed to the inner member. The antenna device according to claim 1, wherein the circuit board is housed in the inner member within a range of a dimension of the inner member in a height direction. The element surface of the antenna element is oriented in a direction intersecting the substrate surface of the circuit board, the circuit board is located within the size range of the height direction of the element surface 1. 2. The antenna device according to item 2. The antenna device according to claim 3, wherein the antenna element is fixed to an outer surface of the inner member extending in the height direction. The antenna element has a joint portion parallel to the substrate surface of the circuit board, an electrode portion is provided on the substrate surface, and a press-contact mechanism for press-contacting the joint portion with the electrode portion is provided. Item 5. The antenna device according to any one of items 1 to 4. The antenna device according to claim 5, wherein the press-contact mechanism is a screw member that passes through the joining portion and the electrode portion and fastens a part of the circuit board and a part of the case. At least one of a recessed portion that is recessed in the height direction and a hole portion that penetrates in the height direction is formed in the inner member, and the electronic component mounted on the circuit board has the recessed portion and the hole portion. The antenna device according to any one of claims 1 to 6, which is located inside at least one of them. The antenna device according to claim 1, wherein inside the case, the circuit board is sandwiched by a plurality of inner members from above and below in a height direction.

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