JP2018014769A - Antenna device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antenna device which is suitable for common usage of components, is inexpensive, and lightweight by forming a base structure in which a sheet metal component is used at a position where ground connection is made and a periphery of the sheet metal component is integrally molded by resin.SOLUTION: An antenna device includes: a case 2; an amplifier substrate 3 which is housed in the case and receives a signal from an antenna element; and a base 20 which closes a bottom surface of the case. A nut 40 serving as a metal fastening component is integrally provided at the base 20, and the base 20 has a sheet metal component 21 which makes ground connection between a ground electrode of the substrate 3 and a vehicle panel 10. A resin part 30 is formed by integrally molding a periphery of the sheet metal component 21 with resin. The sheet metal component 21 has an arm 23, and the arm 23 is electrically connected with the ground electrode.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an antenna device suitable for a vehicle-mounted antenna device or the like attached to a vehicle panel.

  As shown in FIG. 10, an in-vehicle radio antenna apparatus generally includes an element 1 including an antenna element that receives radio waves, a case 2 that protects the inside from wind and rain, an amplifier board 3 that amplifies a high-frequency signal received by the element 1, It has a cable (not shown) for transmitting signals, a base 4 for holding each component, and a nut 6 for fixing the base 4 to the vehicle panel 10. The amplifier board 3 is held on the base 4, the bottom surface of the case 2 is closed by the base 4, and the amplifier board 3 is stored in the case 2. The element 1 is attached to the upper part of the case 2 (for example, the case 2 side is screwed with a female screw and the element 1 side is screwed with a male screw).

  The base 4 of the in-vehicle radio antenna apparatus has functions such as holding each component, fixing to the vehicle panel 10 via the nut 6, and grounding the vehicle panel 10. For this reason, metal die-cast products have been mainly used in the past because they are a production method using a material having a large degree of freedom in production shape, high strength, and electrical continuity.

  In general, since the specific gravity of metal is large, there is a problem that the base of a metal die-cast product is heavy. In addition, since the melting point is high as a material, the mold equipment is expensive and the product price is high. Further, since electricity is conducted, there is a risk of causing a short-circuit accident or the like between the signal transmission of the received high-frequency signal or the core wire of the power supply cable. On the other hand, there was a structure in which a part of the base was made of resin aiming at weight reduction and cost reduction, but the metal part still used a die-cast product, and there was no cost advantage.

  Patent Document 1 below is an example of a metal die casting base.

JP 2009-296095 A

  As described above, a conventional base for an in-vehicle antenna device is generally manufactured by metal die casting, but the resin is superior in terms of weight reduction and cost. However, since the resin is an insulator, it is unsuitable for the base of a vehicle-mounted antenna device that requires ground connection between the amplifier board and the vehicle panel.

  The present invention has been made in view of such a situation, and its purpose is to use a sheet metal part at a place where ground connection is made and to provide a base structure with resin around it, so that it is suitable for common use of parts. Another object of the present invention is to provide an inexpensive and lightweight antenna device.

One embodiment of the present invention is an antenna device. The antenna device includes a case, a substrate that is housed in the case and receives a signal from the antenna element, and a base that closes a bottom surface of the case,
The base includes a sheet metal part that performs ground connection between the ground electrode of the substrate and the vehicle panel, and a resin portion,
A metal fastening part is integrally provided and electrically connected to the sheet metal part,
The resin part is provided around the sheet metal part, and has an attachment hole for attaching to the case at a peripheral part that does not overlap the sheet metal part.

  In the above aspect, it is preferable that the sheet metal part has at least one arm portion rising from the bottom surface portion, and the arm portion is electrically connected to the ground electrode of the substrate.

  There are a plurality of the arm portions, the substrate is held by the plurality of arm portions, and at least one of the arm portions has a bent portion at a tip portion, and the bent portion is bent. It may be soldered to the ground electrode.

  It is preferable that an edge portion of the bottom surface portion is bent to form a reinforcing rib.

  It should be noted that any combination of the above-described constituent elements, and those obtained by converting the expression of the present invention between methods and systems are also effective as aspects of the present invention.

  According to the antenna device of the present invention, a base structure in which a sheet metal part is used at a place where ground connection is made and a resin is provided around the part can be configured to be mostly made of a lighter resin than a metal. For this reason, it can be manufactured at a lower cost as compared with die casting while reducing the weight. Moreover, sheet metal parts can be used in common and the shape of the resin molded product can be changed to cope with various situations and is suitable for common parts.

The disassembled side view which shows the whole structure of embodiment of the antenna apparatus which concerns on this invention. In embodiment, the sectional side view of the base which blocks the bottom part of a case. The perspective view of a base similarly. The perspective view of the sheet-metal component provided in the said base for earth | ground connection. In embodiment, the perspective view of the state which fixed the amplifier board | substrate on the base. In embodiment, the base is mounted in a vehicle panel, and the side sectional view of the state where the bolt part of the metal mounting bracket was screwed and tightened to the nut on the base side. Explanatory drawing at the time of changing the convex part shape of a base according to the hole shape by the side of a vehicle panel, using the said sheet-metal part in common. Explanatory drawing at the time of changing the outline shape of a base according to the bottom face shape of a case using the said sheet-metal part in common. It is other embodiment of this invention, Comprising: The sectional side view of the structure using the metal volt | bolt instead of the metal nut provided in the base side. An exploded side view of a conventional in-vehicle radio antenna device.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or equivalent component, member, process, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  1 to 6 show an embodiment of an antenna device according to the present invention, which shows an example of an in-vehicle radio antenna device. As shown in FIG. 1, the in-vehicle radio antenna apparatus includes an element 1 including an antenna element (such as a rod antenna and a helical coil) that receives radio waves, a resin case 2 that protects the inside from wind and rain, and a high-frequency signal received by the element 1 Amplifier board 3, a cable 5 for transmitting signals amplified by the amplifier board 3 and power supply to the amplifier board 3 (see FIG. 2, etc.), a base 20 for holding each component, a metal plate such as a vehicle roof And a metal fitting 50 with a claw for fixing the base 20 to the vehicle panel 10 having a shape. The element 1 is attached to the upper part of the case 2 (for example, the case 2 side is screwed with a female screw and the element 1 side is screwed with a male screw).

  As shown in FIGS. 2 and 4, the base 20 is formed by integrally molding a resin around the sheet metal part 21 to which a metal nut 40 as a metal fastening part is fixed by welding or the like (so-called insert molding). 21 and a resin portion 30 integrated therewith. The base 20 is arranged to close (close) the bottom surface of the case 2, and is fixed to the case 2 with screws or the like using the mounting holes 31 on the peripheral edge of the resin portion 30.

  As shown in FIG. 4, the sheet metal part 21 includes a bottom surface portion 22 and a pair (a plurality of) arm portions 23 that rise vertically at diagonal positions with respect to the bottom surface portion 22. In addition, a circular step surface 24 is formed on the bottom surface portion 22 by squeezing, and an edge portion of the bottom surface portion 22 is bent to form a reinforcing rib 25. The step surface 24 and the reinforcing rib 25 are provided to improve the bending strength when the thickness of the sheet metal part 21 is thin. A punched hole 22a is formed in the bottom surface portion 22 (step surface 24) for weight reduction. As can be seen from FIG. 2, the metal nut 40 is a stepped nut (pilot nut) having a convex portion 41 at the center, and the nut positioning hole 26 into which the convex portion 41 is fitted at the center of the bottom surface portion 22. Is formed. In order to ensure electrical connection between the sheet metal part 21 and the metal nut 40, the metal nut 40 is fixed to the sheet metal part 21 by welding or soldering.

  The resin portion 30 has a substantially oval outline, and a fitting convex portion 32 having a shape that fits into the rectangular mounting hole 11 of the vehicle panel 10 (for example, a vehicle roof) is formed at the center portion on the lower surface side. The fitting convex portion 32 is formed with a hole portion 33 through which the female screw hole 42 of the metal nut 40 is exposed. Further, a hole 34 through which the female screw hole 42 of the metal nut 40 is exposed is also formed on the upper surface side of the resin portion 30. A metal tube 55 is press-fitted into the hole 33 after the resin portion 30 is molded. The upper end of the metal tube 55 is in contact with the convex portion 41 of the metal nut 40. A cable lead hole 39 is formed in the fitting convex portion 32 so as to penetrate the fitting convex portion 32, and the cable 5 connected to the amplifier board 3 is drawn to the outside through the cable lead hole 39.

  As shown in FIGS. 2 and 3, the plurality of arm portions 23 rising from the sheet metal part 21 protrude from the upper surface of the resin portion 30, and the upper end portion of the arm portion 23 can be folded by making a notch 23 a. It is a bent portion 23b. A plurality of bosses 35 are formed on the upper surface of the resin portion 30 to support the lower surface of the amplifier substrate 3 at a predetermined height. Then, as shown in FIG. 5, the amplifier board 3 is placed on the base 20, that is, between the pair of diagonal arm portions 23, and then the bent portion 23 b of the arm portion 23 is bent to ground the amplifier substrate 3. 3a is soldered and electrically connected with a conductive adhesive or the like. As shown in FIG. 5, the amplifier board 3 is mounted on the base 20, and the case 2 is put on the base 20 while being held by the arm 23, and the amplifier board 3 is housed in the case 2.

  FIG. 6 shows a state in which the base 20 is placed on the vehicle panel 10, and the bolt portion 51 of the metal mounting bracket 50 is screwed and tightened to the nut 40 on the base side. However, illustration of the case 2 and the amplifier board 3 is omitted. As shown in FIG. 6, the mounting to the vehicle panel 10 such as a vehicle roof is performed by fitting the fitting convex portion 32 on the lower surface of the base 20 into the rectangular mounting hole 11, and the bolt portion 51 of the metal mounting bracket 50 with claws. Is screwed into the female screw hole 42 of the metal nut 40 and the inward L-shaped bent arm portion 53 formed integrally with the claw 52 is engaged with the locking groove 37 on the lower surface of the resin portion 30. Do by tightening with. Thereby, the claw 52 provided around the bolt portion 51 of the metal mounting bracket 50 bites into the surface of the vehicle panel 10 and the metal mounting bracket 50 is electrically connected to the vehicle panel 10. Accordingly, the ground electrode 3a of the amplifier board 3 is electrically connected to the vehicle panel 10 through the path of the arm part 23, the bottom part 22, the metal nut 40, the bolt part 51 of the metal mounting bracket 50, and the claw 52 of the sheet metal part 21, An earth connection of the earth electrode 3a to the vehicle panel 10 is achieved. Since the metal tube 55 is around the bolt portion 51, the tightening limit of the metal mounting bracket 50 is restricted to a position where the upper surface of the base of the claw 52 contacts the metal tube 55. Further, the sheet metal part 21 is set larger than the outer diameter of the tip of the claw 52. Accordingly, since the tip of the claw 52 is located inside the lower surface region (the range indicated by the arrow E in FIG. 6) of the sheet metal part 21, the sheet metal part 21 receives the pressing force of the claw tip generated by tightening by the bolt part 51. be able to. Thereby, a large stress is not applied to the resin portion 30 of the base 20 and a secure fastening can be achieved.

  According to the present embodiment, the following effects can be achieved.

(1) By changing most of the material of the base 20 from a metal having a high specific gravity to a resin having a low specific gravity, the weight can be reduced compared to a conventional metal die-cast base.

(2) In the case of metal die casting, since a metal having a high melting point is used as a material, the mold equipment is expensive. On the other hand, resin molding is simple and the material itself is cheap. Therefore, the base 20 in which the resin is provided around the sheet metal part 21 can be manufactured at a lower cost.

(3) Since the conventional metal die-cast base is a conductor, there is a risk of a short circuit accident when the radio signal line or the power line of the amplifier board 3 comes into contact with the base. In the base 20 of the present example in which the sheet metal part 21 is covered with the part 30, since electricity is not conducted on the surface of the base 20, a short circuit between the radio signal line and the power line of the amplifier board 3 can be prevented, and a highly safe product Become.

(4) A material with excellent solderability such as tinplate can be selected as the material of the sheet metal part 21 and screws or the like are used to hold the amplifier board 3 in order to reduce the number of parts and reduce the cost. It can be held without soldering.

  FIG. 7 illustrates a case where the sheet metal part is commonly used and the convex shape of the base 20 is changed in accordance with the shape of the mounting hole on the vehicle panel side, and the sheet metal part 21 in FIG. Through the embodiment described with reference to FIG. 5, the fitting convex portion 32A of the resin portion 30 formed integrally with the sheet metal part 21 is formed in a substantially square tube shape as shown in FIG. By doing so, a base structure suitable for the substantially square mounting hole 11A of FIG. Further, by using the common sheet metal part 21, the fitting convex part 32B of the resin part 30 is formed in a substantially rectangular tube shape having a substantially rectangular cross section as shown in FIG. A base structure that conforms to the substantially rectangular mounting hole 11B can be realized.

  As described with reference to FIG. 7, the sheet metal part 21 for holding the amplifier board 3 and grounding is used as a common part, and by changing the resin molding shape around it, the mounting holes can have various shapes and sizes on the vehicle panel. A compatible structure can be realized.

  FIG. 8 illustrates a case where the sheet metal part is commonly used and the outline shape of the base 20 is changed in accordance with the shape of the bottom surface of the case. The sheet metal part 21 in FIG. If the case bottom shape is small, the resin portion 30A having a small contour shape may be molded integrally with the sheet metal part 21 as shown in FIG. In the case of being large, the resin portion 30B having a large contour shape may be formed integrally with the sheet metal part 21 as shown in FIG.

  As described with reference to FIG. 8, the sheet metal part 21 that holds the amplifier board 3 and connects to the ground is used as a common part, and a structure that can cope with the difference in the case size of the antenna device is realized by changing the resin molding shape around it. it can.

  FIG. 9 shows another embodiment of the present invention, in which only the portion of the base 20 is shown. In this case, a bolt mounting hole 25A is formed in the center of the bottom surface portion 22 of the sheet metal part 21 instead of the nut positioning hole, and the head of the metal bolt 45 as a metal fastening part inserted through the bolt mounting hole 25A is welded. It is fixed to the sheet metal part 21 by soldering. For attachment to the vehicle panel, a nut 6 (for example, a nut with a metal claw) can be used as in the case of the conventional example of FIG.

  In the case of the embodiment of FIG. 9 as well, the same operations and effects as those of the embodiment shown in FIGS. 1 to 5 can be obtained except that the metal fastening part is changed.

  The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

  The metal nut 40 may be fixed and electrically connected to the sheet metal part 21 by mechanical caulking. It is also possible to directly process the female screw after burring the sheet metal part 21.

  If there is at least one arm portion 23 of the sheet metal part 21, electrical connection with the ground electrode 3 a of the amplifier substrate 3 is possible. However, a plurality of amplifier substrates 3 are preferably provided for mechanical holding.

  Depending on the type of antenna device, an amplifier may not be mounted on the substrate. However, it is obvious that the present invention can also be applied to an antenna device having a substrate in which no amplifier is mounted in a case.

DESCRIPTION OF SYMBOLS 1 Element 2 Case 3 Amplifier board 3a Ground electrode 4, 20 Base 6, 40 Nut 10 Vehicle panel 11, 11A, 11B Mounting hole 21 Sheet metal part 22 Bottom part 23 Arm part 23a Notch 23b Bending part 25 Reinforcement rib 26 Nut positioning hole 30, 30A, 30B Resin parts 32, 32A, 32B Fitting convex part 41 Convex part 50 Metal mounting bracket 51 Bolt part 52 Claw

Claims (4)

A case, a board that is housed in the case and receives a signal from an antenna element, and a base that closes a bottom surface of the case,
The base includes a sheet metal part that performs ground connection between the ground electrode of the substrate and the vehicle panel, and a resin portion,
A metal fastening part is integrally provided and electrically connected to the sheet metal part,
The antenna device, wherein the resin portion is provided around the sheet metal part, and has a mounting hole for attaching to the case at a peripheral edge that does not overlap the sheet metal part.   The antenna apparatus according to claim 1, wherein the sheet metal part has at least one arm portion rising from a bottom surface portion, and the arm portion is electrically connected to a ground electrode of the substrate.   There are a plurality of the arm portions, the substrate is held by the plurality of arm portions, and at least one of the arm portions has a bent portion at a tip portion, and the bent portion is bent. The antenna device according to claim 2, wherein the antenna device is soldered to the ground electrode.   The antenna device according to claim 2, wherein an edge portion of the bottom surface portion is bent to form a reinforcing rib.