Antenna device manufacturing method

Abstract

This method for manufacturing an antenna device (100) includes a melting step and a removal step. The antenna device (100) comprises: an antenna section (20) on which is wound a coil wire (40) having a coil core (47) covered by an insulation film (46); and a base (30) having a pad section (331) for which a portion of the coil wire (40) is soldered using a brazing filler material (50). In the melting step, a laser is radiated on the brazing filler material (50) supplied onto the pad section (331), melting the brazing filler material (50). In the removal step, the coil wire (40) is immersed in the melted brazing filler material (50) and a portion of the insulation film (46) is removed from the coil wire (40), and the coil wire (40) and the pad section (331) are joined by the brazing filler material (50).

Description

Technical Field

[0001] The present invention relates to an antenna device and a method for manufacturing the antenna device.

Background Art

[0002] Some antenna devices have an antenna around which a coil wire is wound, and the coil wire is electrically connected to a circuit section by soldering or the like. Regarding this type of technology, Patent Document 1 below discloses a method for manufacturing an RFID transponder having an antenna (4) made from a winding wire (2), the winding wire (2) being soldered to a solderable contact area (12). Specifically, as shown in FIG. 1 of Patent Document 1, a solderable contact area (12) is provided on the upper surface of a semiconductor die (6). The contact area (12) is a metal plating made of a nickel-based alloy or the like. The end of the winding wire (2) is soldered to the contact area (12). Specifically, the area to be soldered is irradiated with a laser, and the solder is melted by the laser so that the winding wire (2) and the contact area (12) are joined.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Generally, the coil wires wound around antennas are covered with an insulating coating. In order to solder the winding wire (2) to the contact area (12), as described in Patent Document 1, it is necessary to remove the insulating coating from at least the portion of the winding wire (2) that will be soldered beforehand. Patent Document 1 states that the process of removing the insulating coating before the soldering process is performed using the same laser device used to solder the winding wire (2) to the contact area (12). In other words, it is necessary to perform a process of removing the insulating coating before the soldering process. This leads to the problem of increased manufacturing time in the production of antenna devices. This type of problem is not limited to solder, but occurs in all brazing processes using other metal brazing materials.

[0005] This invention has been made in view of the above-mentioned problems, and provides an antenna device and a method for manufacturing an antenna device with fewer manufacturing steps. [Means for solving the problem]

[0006] The present invention relates to a method for manufacturing an antenna device comprising: an antenna section in which a coil wire, whose coil core is covered with an insulating film, is wound; and a base having a pad section in which a portion of the coil wire is brazed with a brazing material, the method comprising: a melting step in which a laser is irradiated onto the brazing material supplied onto the pad section to melt the brazing material; and a removal step in which the coil wire is immersed in the molten brazing material so that a portion of the insulating film is removed from the coil wire by the heat of the brazing material, and the coil wire and the pad section are joined by the brazing material. The process includes a wire arrangement step performed before the melting step, wherein the base has a wire fixing portion for fixing the coil wire, in the wire arrangement step one end of the coil wire is fixed to the wire fixing portion, a portion of the coil wire is placed on the brazing material provided on the surface of the pad portion, and in the wire arrangement step a pressurized portion which is a portion of the length between the one end and the portion of the coil wire is pressed toward the base so that the coil wire is pressed against the brazing material. It is characterized by the following: [Effects of the Invention]

[0008] According to the manufacturing method of the present invention, the insulating film immersed in the brazing material is removed from the coil wire by the heat of the molten brazing material. This allows the brazing process and the process of removing the insulating film from the coil wire to be performed simultaneously, thereby reducing the manufacturing time of the antenna device. [Brief explanation of the drawing]

[0009] The aforementioned objectives, as well as other objectives, features, and advantages, will become even clearer from the preferred embodiments described below and the accompanying drawings.

[0010] [Figure 1] This is a perspective view showing an example of an antenna device according to the first embodiment of the present invention. [Figure 2] This is a top view of the circuit section of the antenna device according to the first embodiment. [Figure 3] This is a longitudinal cross-sectional view of the antenna device according to the first embodiment, taken in the direction of arrow III-III, along the dashed line shown in Figure 2. [Figure 4] This is an enlarged view of X shown in Figure 2 of the antenna device according to the first embodiment. [Figure 5] This is a longitudinal cross-sectional view of the antenna device according to the first embodiment, taken in the direction of arrow VV, along the dashed line shown in Figure 4. [Figure 6] This is a perspective view of an antenna device to show an example of a manufacturing method for an antenna device according to the first embodiment. [Figure 7] This is a top view of an antenna device to show an example of a manufacturing method for an antenna device according to the first embodiment. [Figure 8] This is a longitudinal cross-sectional view of the antenna device according to the first embodiment, taken in the direction of arrow VIII-VIII, along the dashed line shown in Figure 7. [Figure 9] This is a longitudinal cross-sectional view of the antenna device according to the first embodiment, taken in the direction of arrow IX-IX, along the dashed line shown in Figure 7. [Figure 10] This is a perspective view showing an example of a pressurizing jig used in the manufacturing method of the antenna device according to the first embodiment. [Figure 11] This is a perspective view showing an example of the installation of a pressure jig in the manufacturing method of an antenna device according to the first embodiment. [Modes for carrying out the invention]

[0011] The various components of the antenna device of the present invention do not need to be independent entities; it is permissible for multiple components to be formed as a single member, for one component to be formed from multiple members, for one component to be part of another component, for a part of one component to overlap with a part of another component, and so on. Furthermore, while the method for manufacturing the antenna device of the present invention may be described using a series of steps described in order, the order of these steps does not limit the order or timing of their execution. Therefore, when implementing the method for manufacturing the antenna device of the present invention, the order of the steps can be changed to the extent that it does not impede the content, and some or all of the execution timings of the steps may overlap.

[0012] Embodiments of the present invention will be described below with reference to the drawings. In each drawing, corresponding components are denoted by the same reference numeral, and redundant explanations will be omitted as appropriate. In this embodiment, the directions of front, back, left, right, up, and down are defined and explained as shown in the figures. Furthermore, the front end of the base 30, antenna section 20, or coil wire 40 may be referred to as the front end, and the rear end as the rear end. The left-right direction may be referred to as the width direction, and the up-down direction as the height direction. In the left-right direction, the direction from the center line of the base toward the left or right is referred to as the outward side or outward direction, and the direction from the left or right toward the center line of the base is referred to as the inward side or inward direction. Additionally, the direction perpendicular to the up-down direction, i.e., the left-right and front-back directions together, may be referred to as the lateral direction. However, these are merely definitions for convenience to briefly explain the relative relationships of the components and do not limit the direction during manufacturing or use of the product implementing this invention. Furthermore, in this invention, "plane" refers to a shape that is physically formed with the goal of being a plane, and naturally, it does not need to be a geometrically perfect plane.

[0013] <First Embodiment> (Overview of the antenna system) FIG. 1 is a perspective view showing an example of an antenna device 100 according to a first embodiment of the present invention.

[0014] First, an overview of the antenna device 100 of this embodiment will be described. The antenna device 100 includes an antenna unit 20 and a base (circuit unit 33) having a pad unit 331. The antenna unit 20 has a coil wire 40 wound around a coil core 47 and an insulating film 46 covering the coil core 47. The coil wire 40 and the pad unit 331 are joined by an adhesive 50.

[0015] Next, details of the antenna device 100 of this embodiment will be described using FIGS. 1 to 5. The antenna device 100 is used in a small portable communication system such as a transceiver used in a keyless entry system, for example, and can also be used as an RFID transponder for identifying articles such as products. For example, the antenna unit 20 functions as an antenna for transmitting and receiving radio waves in the antenna device 100. In this embodiment, the antenna unit 20 has a bobbin 21, and the coil wire 40 is wound around the bobbin 21. As shown in FIG. 1, both ends of the coil wire 40 are disposed on the base 30 side (rear end side) of the bobbin 21. Also, the coil wire 40 (coil portion 49) is wound around the middle portion in the axial direction of the bobbin 21. That is, a part of the front end of the bobbin 21 is not wound with the coil wire 40. In addition, in the coil portion 49 shown in FIG. 1, illustration of each individual coil wire 40 wound around the bobbin 21 is omitted. The same applies to FIGS. 3, 6, 7, 9, and 11. The antenna unit 20 is not limited to the shape of this embodiment and includes various shapes that function as an antenna. For example, a hollow coil without using a bobbin 21 and having a hollow inside the coil portion 49 may be used. Also, the coil wire 40 may be wound so as to be annularly arranged on a plane. Both ends of the coil wire 40 are drawn out to the base 30 side.

[0016] The coil wire 40 is a conductive wire. In this embodiment, the coil wire 40 has a coil core 47 (see Figure 4) made of a conductive metal such as copper, which is covered with an insulating coating 46 (see Figure 4). Examples of materials for the insulating coating 46 include resins such as polyurethane and polyimide. In this embodiment, the core 21 is inserted into a core insertion hole 316 (see Figure 3) provided on the front end side of the base 30, which will be described later, and fixed to the base 30. Also, as shown in Figure 3, a chamfered portion 316a is provided at the opening of the core insertion hole 316 to facilitate the insertion of the core 21 into the core insertion hole 316. The end face of the core 21 (the face facing the rear end) is in contact with the bottom face (the face facing the rear end) of the core insertion hole 316.

[0017] The base 30 (circuit section 33) is a component for arranging the circuit body 333 to which the coil wires 40a and 40b drawn out from the coil section 49 are connected. In addition to the circuit section 33, the base 30 may include a wire arrangement section 31 used in the manufacturing method of the antenna device 100, which will be described later. Hereinafter, the circuit section 33 may be referred to as the base 30, and the circuit section 33 and the wire arrangement section 31 may be referred to collectively as the base 30. In this embodiment, the circuit section 33 has the shape of a column with a substantially semicircular base, as shown in Figure 1. The semicircular surface at the base of the column faces in the front-to-back direction, the flat portion of the side surface of the column (top surface 33a) faces upward, and the curved circumferential surface of the side surface of the column faces downward. The shape of the circuit section 33 is not limited to a column with a semicircular base, but may also be a flat plate, a rectangular prism, a cylinder, etc. In this embodiment, the upper surface 33a of the circuit section 33 is provided with a recessed mounting hole 334 on the lower side (see Figures 3 and 8). In this embodiment, as shown in Figure 3, the mounting hole 334 is open on the upper and rear end sides. The mounting hole 334 may also be open only on the upper side. The bottom surface of the mounting hole 334 has sufficient dimensions and shape to accommodate the circuit body 333, which will be described later. Specifically, in this embodiment, in order to accommodate the circuit body 333 which is rectangular in the front-to-back direction, the mounting hole 334 also has a rectangular shape which is rectangular in the front-to-back direction. In addition, the length of the mounting hole 334 in the width direction and the front-to-back direction is equal to or greater than the length of the circuit body 333 in the width direction or the front-to-back direction, respectively. In this embodiment, the widthwise and front-to-back lengths of the mounting hole 334 are greater than the widthwise or front-to-back lengths of the circuit body 333, respectively. As shown in Figure 2, there are gaps between the circuit section 33 and the circuit body 333 at the front end, left side, and right side of the circuit body 333. The circuit body 333 is housed inside the installation hole 334. Housed means that part or all of the circuit body 333 is positioned inside the installation hole 334. In this embodiment, as will be described later, the upper surface 333a of the circuit body 333 is lower than the upper surface 33a of the circuit section 33. That is, as shown in Figure 3, the entire circuit body 333 is housed in the installation hole 334, but it is not limited to this. The upper part of the circuit body 333 may be above the upper surface 33a of the circuit section 33. Also, the installation hole 334 may not be provided in the circuit section 33, and the circuit body 333 may be positioned on the upper surface 33a of the circuit section 33.

[0018] The circuit body 333 is a component that connects to the coil wire 40 and has a pad portion 331 (see Figures 2 and 3), which will be described later, and is a circuit board on which semiconductor components and the like are mounted. The circuit board may be coated with resin or the like, and may be housed inside a hollow component, for example. In this embodiment, the circuit body 333 and the circuit portion 33 on which the circuit body 333 is installed are separate components, but this is not limited to this. The circuit body 333 and the circuit portion 33 may be configured together as a single component. A pad portion 331 is located on the upper surface 333a of the circuit body 333. The pad portion 331 is the area where brazing material 50 for brazing the coil wire 40 is supplied. Specifically, the pad portion 331 is a part to which a conductive metal such as copper or nickel is plated in a thin film. The pad portion 331 is connected to components that make up the circuit, such as a semiconductor substrate, and the coil wire 40 and the components that make up the circuit are electrically connected via the pad portion 331. The thickness (length in the height direction) of the pad portion 331 is preferably smaller than the base height h2 (height from the top surface 333a of the circuit portion 33 to the top surface 33a of the circuit body 333, with the top surface 333a of the circuit body 333 as the reference), as described later.

[0019] As shown in Figures 2 and 4, in this embodiment, two pad portions 331 are provided at two locations on the upper surface 333a of the circuit body 333. This is for joining both ends of the coil wire 40 to the respective pad portions 331. More specifically, in this embodiment, the pad portions 331 are located at the rear end side of the upper surface 333a of the circuit body 333, one in the left region and one in the right region. The left and right pad portions 331 are positioned symmetrically with respect to the center line in the left-right direction of the circuit body 333, and also have a symmetrical shape. In this embodiment, both ends of the coil wire 40 are joined to a pair of pad portions 331 provided on the base 30 by brazing material 50. Each of the pair of pad portions 331 is formed in a substantially rectangular shape with its longitudinal side in the front-to-back direction. Furthermore, each rectangle has a shape in which one of the inner corners of the pair of pad portions 331 is chamfered to form a hypotenuse 331a (see Figure 4). Specifically, the corner located on the inner and front end side of the rectangle is chamfered. That is, the pad portion 331 has a pentagonal shape. The hypotenuse 331a is aligned with the extending direction of the coil wire 40. Here, the extending direction of the coil wire 40 is the axial direction of the coil wire 40. The extension direction of the coil wire 40 and the hypotenuse 331a are said to be aligned, which means that the extension direction of the coil wire 40 and the hypotenuse 331a are preferably approximately parallel, and that the acute angle between the extension direction of the coil wire 40 and the hypotenuse 331a is at least 45 degrees or less.

[0020] The coil wire 40, which is drawn out from the antenna section 20, is placed on the base 30 and connected to the pad section 331. As shown in Figure 1, the corner of the boundary between the front side surface and the upper surface 33a of the base 30 is chamfered to form an inclined surface 33c. In addition, a pair of guide portions 335 are provided on the front side of the base 30, spaced apart in the left-right direction, and protruding beyond the upper surface 33a of the circuit portion 33. As shown in Figure 2, the guide portions 335 are positioned outward from each of the pair of pad portions 331. The guide portion 335 is elongated in the front-rear direction and has a roughly rectangular shape, with the corner of the boundary between the rear side surface and the outer side surface being chamfered with a rounded edge. That is, the outer surface 335a (see Figure 2) located on the outer side of the guide portion 335 has a partially curved circumferential surface. As shown in Figures 1 and 2, the coil wire 40 drawn out toward the base 30 is positioned along the inclined surface 33c and the outer surface 335a of the guide portion 335. Furthermore, the coil wire 40 is positioned along the upper surface 33a of the circuit portion 33 and the outer surface 335a of the guide portion 335. In other words, the coil wire 40 is bent along the curved circumferential surface which is part of the outer surface 335a. One end of the coil wire 40 is brazed to a pad portion 331 which is positioned inward from the guide portion 335. Also, as shown in Figures 2 and 4, in this embodiment, one end of the coil wire 40 protrudes partially toward the rear end from the brazing material 50.

[0021] Examples of brazing materials 50 used to braze the coil wire 40 and the pad portion 331 include metal brazing materials such as solder and gold brazing material. The brazing material 50 melts in a melting process described later, and the molten brazing material 50 comes into contact with the coil core 47 of the coil wire 40 and the pad portion 331, forming an alloy layer between the coil core 47 or the pad portion 331. The following explanation assumes that the brazing material 50 is solder 50.

[0022] A portion of the coil wire 40 is embedded in the solder 50. Here, "a portion of the coil wire 40 is embedded in the solder 50" is not limited to the case where the solder 50 covers the entire radial length of the coil wire 40, as shown in solder 50a in Figures 4 and 5, and the entire coil wire 40 is covered in solder 50 in a portion of its length. For example, as shown in solder 50b in Figures 4 and 5, there may be no portion where the entire radial length of the coil wire 40 is covered in solder 50, and a portion of the radial length of the coil wire 40 may be covered in solder 50 while another portion is not. In other words, only a portion of the radial length may be the external region described later, and the other portion of the radial length may be the internal region described later. Preferably, at a certain point on the coil wire 40, more than half of the circumference of the coil wire 40, and more preferably more than three-quarters of the circumference, is covered in solder 50. Here, the radial direction refers to the direction perpendicular to the axis of the coil wire 40, that is, the direction radiating from the axis of the coil wire 40 toward the circumferential surface.

[0023] (Manufacturing method for antenna devices) Next, a method for manufacturing the antenna device 100 of this embodiment (hereinafter sometimes referred to as "this method") will be described.

[0024] First, I will explain the outline of this method. The antenna device 100 manufactured by this method comprises, as described above, an antenna section 20 in which a coil wire 40, whose coil core 47 is covered with an insulating film 46, is wound, and a base 30 having a pad section 331 in which a part of the coil wire 40 is brazed with a brazing material 50. This method includes a melting step and a removal step. In the melting step, a laser is irradiated onto the brazing material 50 supplied onto the pad portion 331, causing the brazing material 50 to melt. In the removal step, the coil wire 40 is immersed in the molten brazing material 50, and a portion of the insulating film 46 is removed from the coil wire 40, joining the coil wire 40 and the pad portion 331 with the brazing material 50. Furthermore, in this embodiment of the method, as will be described later, a wire placement step is performed before the melting step and the removal step, and a cutting step is performed after the melting step and the removal step.

[0025] First, let's explain the base 30 in this method. In this method, the base 30 includes a circuit section 33 and a wire arrangement section 31, as shown in Figure 6. The wire arrangement section 31 is a part of the base 30 for fixing the ends of the coil wires 40. In this embodiment, the wire arrangement section 31 is a long plate-like member in the front-rear direction. That is, the wire arrangement section 31 extends in the front-rear direction. The main surface of the plate-like portion (flat plate section 315) of the wire arrangement section 31 faces in the up-down direction. The shape of the wire arrangement section 31 is not limited to a flat plate, and may be another shape such as a column. Furthermore, the wire arrangement section 31 is located in the circuit section 33 at a position opposite to the antenna section 20, that is, on the rear end side of the circuit section 33. In this embodiment, the wire arrangement section 31 is integrally formed with the circuit section 33. Also, as shown in Figure 9, the upper surface 315a of the flat plate section 315 is located below the upper surface 33a of the circuit section 33. The base 30 (wire arrangement section 31) has a wire fixing section 312 for fixing the coil wire 40. The wire fixing section 312 is the part to which the end of the coil wire 40 is fixed. In this embodiment, the wire fixing section 312 is a rectangular prism that protrudes upward from the upper surface 315a of the flat plate section 315 at the rear end. As will be described later, the coil wire 40 can be fixed by wrapping the coil wire 40 around the protruding rectangular prism. The coil wire 40 is not limited to a shape that protrudes upward, but may have a shape or function for fixing one end of the coil wire 40, such as a protrusion in the left-right direction, towards the rear end, or downward, or a hook shape. Furthermore, a rectangular hollow hole 314 (see Figure 7) is provided between the support portion 311 and the wire fixing portion 312 of the flat plate portion 315, with the hole being elongated in the front-to-back direction.

[0026] Next, we will explain this method in detail, step by step, using Figures 6 to 11. In this embodiment, solder 50 is applied to the surface of the pad portion 331 in advance before the wire placement process described later. Specifically, as shown in Figure 8, it is formed in a mountain shape with a slope 51 that slopes downward from the center of the pad portion 331 towards the periphery of the pad portion 331. The solder 50 is in contact with almost the entire surface of the pad portion 331. In addition, the slope 51 of the solder 50 is arched upward, and the solder 50 as a whole has a dome shape. The solder 50 is cooled and solidified. In this case, it is preferable that the distance from the surface of the pad portion 331 to the highest point (vertex 52) of the solder 50 (thickness of the solder 50) is greater than the base height h2 (see Figure 9), which will be described later, and is greater than or equal to the diameter of the coil wire 40.

[0027] Next, a wire placement process is performed in which the ends of the coil wire 40 are placed on the base 30. In the wire placement process, one end of the coil wire 40 (fixing portion 43) is fixed to the wire fixing portion 312, and a portion of the coil wire 40 (pad portion placement portion 42) is placed on the brazing material 50 provided on the surface of the pad portion 331. Specifically, as shown in Figures 6 and 7, one end of the coil wire 40, which is drawn out from the antenna section 20 around which the coil wire 40 is wound, is pulled out towards the circuit section 33. The pulled-out coil wire 40 is positioned along the inclined surface 33c, the upper surface 33a of the circuit section 33, and the outer surface 335a of the guide section 335, as described above. As the coil wire 40 follows the R-shaped surface of the outer surface 335a of the guide section 335, the direction in which the coil wire 40 is pulled out changes inward. As a result, the coil wire 40 is pulled out toward the pad section 331. As shown in Figure 7, a portion of the length of the coil wire 40 (the portion positioned on the pad 331) is positioned on the pad 331. Here, a portion of the length of the coil wire 40 being positioned on the pad 331 means that, when viewed from the height direction, a portion of the coil wire 40 and a portion of the pad 331 overlap. Preferably, a portion of the portion positioned on the pad 331 is positioned outward from the vertex 52 (see Figure 8). In this embodiment, as shown in Figure 8, a portion of the pad portion upper arrangement portion 42 is positioned above the pad portion 331 and does not come into contact with the surface of the pad portion 331. Furthermore, the solder 50 and the pad portion upper arrangement portion 42 may or may not be in contact. As shown in Figure 6, when the pad portion upper placement portion 42 is placed on the pad portion 331, the end of the coil wire 40 is wrapped around and fixed to the wire fixing portion 312. At this time, sufficient tension is applied to the coil wire 40 so that the coil wire 40, which is positioned above the base 30, does not become loose.

[0028] In this embodiment, the base 30 has a support portion 311 against which the coil wire 40 is pressed, causing the direction of the coil wire 40 to be reversed. In the wire arrangement process, as shown in Figure 7, a bent portion 45 located between a portion of the coil wire 40 (the portion arranged on the pad portion 42) and one end (the fixed portion 43) is pressed against the support portion 311 of the base 30 and bent. The bent portion 45 is a portion of the length of the coil wire 40 between the portion arranged on the pad portion 42 and the fixed portion 43. More specifically, the bent portion 45 is the length of the coil wire 40 that is curved in contact with the support portion 311 and the length of the portion in its vicinity. The support portion 311 is a member for holding the coil wire 40 in order to maintain the direction in which the coil wire 40 is pulled out. As shown in Figure 6, the support portion 311 is exemplified by a cylindrical projection that protrudes upward from the upper surface 315a of the flat plate portion 315. As will be described later, the coil wire 40 is pressed inward against the support portion 311, thereby maintaining the direction in which the coil wire 40 is pulled out from the guide portion 335 at a predetermined angle. The support portion 311 may also be a projection in the shape of a rectangular prism or a column with a semicircular base. Alternatively, the support portion 311 may be a wall portion that protrudes from the base 30 and has a circumferential surface or plane for contact with the coil wire 40. The support portion 311 is not limited to the above shapes as long as it is a structure that maintains the direction in which the coil wire 40 is pulled out. In this embodiment, the support portion 311 is positioned between the pad portion 331 and the wire fixing portion 312. In other words, the support portion 311 is positioned between the pad portion upper positioning portion 42 and the fixing portion 43 when viewed in the height direction. With this arrangement, the bent portion 45 between the pad portion upper positioning portion 42 and the fixing portion 43 is pressed against the side surface of the support portion 311 and bent. Specifically, a part of the bent portion 45 is positioned along the circumferential surface of the support portion 311 and is curved. At this time, the coil wire 40 is pressed against the side surface of the support portion 311. More specifically, the coil wire 40 is pressed against the side surface of the support portion 311 on the side opposite to the side from which it is drawn out from the coil portion 49 in the left-right direction. For example, as shown in Figure 7, the coil wire 40b (see Figure 1) drawn out from the coil portion 49 to the base 30 on the right side is pressed against the left circumferential surface of the support portion 311. As described above, one end (fixing part 43) of the coil wire 40 that has been bent at the bending part 45 is wrapped around the wire fixing part 312 of the base 30.

[0029] In this embodiment, both ends of the coil wire 40 are positioned on the base 30 as described above. Furthermore, both ends of the coil wire 40 intersect above the base 30 when viewed from the height direction. Specifically, the pressurizing parts 44, 44 intersect above the pressurizing jig installation hole 313 when viewed from the height direction. The pressurizing parts 44 may or may not be in contact with each other. That is, the pressurizing parts 44 may be in a twisted relationship with each other. Because a part of the coil wire 40 intersects at a single point when viewed from the height direction in this way, it becomes easy to position the wire straddling parts 220 on both ends of the coil wire 40 when positioning the pressurizing jig 200 as described later. The pressurized portions 44 of the two coil wires 40a and 40b overlap in the height direction at the aforementioned intersection. At the intersection, coil wire 40a may be above or below coil wire 40b. In Figures 8 and 9, the overlapping of the pressurized portion 44 of coil wire 40a and coil wire 40b is omitted from the illustration.

[0030] By pressing a portion of the coil wire 40 against the support portion 311 in this way, the coil wire 40 drawn out from the antenna portion 20 can be pulled out in any direction and placed on the pad portion 331. Specifically, by changing the position of the support portion 311 in the front-to-back direction, or by changing the width (length in the left-to-right direction) of the support portion 311, the coil wire 40 can be adjusted to pass through any desired position. For example, by positioning the support portion 311 further forward, or by increasing the width of the support portion 311, the coil wire 40 is drawn out at a larger angle with respect to the front-to-back direction, and the coil wire 40 is positioned further inward above the circuit body 333. In this embodiment, the distance between the pad portion 331 and the support portion 311 is less than or equal to half the distance between the pad portion 331 and the wire fixing portion 312. Also, the width of the support portion 311 (or the diameter of the base if the support portion 311 is cylindrical) is greater than the width of the wire fixing portion 312.

[0031] In the wire placement process, when the coil wire 40 is placed on the base 30, the pressurizing section 44 is pressed toward the base 30, causing the coil wire 40 to be pressed against the brazing material 50 (solder 50). The pressurizing section 44 is a portion of the length of the coil wire 40 between one end (fixing section 43) and a portion (a portion placed on the pad section 42). More specifically, the pressurizing section 44 is a portion of the length of the coil wire 40 between the portion in contact with the support section 311 (part or all of the bent section 45) and the portion placed on the pad section 42, and is a portion of the length located above the pressurizing jig installation hole 313, which will be described later. The direction in which the pressurizing section 44 is directed toward the base 30 is, if the base 30 is provided with a cavity such as a pressurizing jig mounting hole 313, the direction toward the pressurizing jig mounting hole 313. In this embodiment, the pressurizing section 44 is applied downward. As a result, the coil wire 40 contacts the solder 50 while applying a resistance force to the solder 50. As will be described later, the coil wire 40 applies a resistance force toward the inclined surface 51 of the solder 50 that is downward, inward, and toward the front end.

[0032] In this embodiment, a pressurizing jig 200 is used to pressurize the pressurizing section 44. As shown in Figure 10, the pressurizing jig 200 has an overall inverted U-shape. The pressurizing jig 200 has a rod portion 230. Arms 210 extend from both ends of the rod portion 230, and a weight portion 211 is provided at the lower end of the arms 210. In this embodiment, the rod portion 230 and the arms 210 are flat plate-shaped, and the weight portion 211 is approximately cubic in shape. A wire straddling portion 220 is provided in the center of the rod portion 230 in the extending direction. The wire straddling portion 220 is the part that directly pressurizes a part of the coil wire 40 (pressurizing portion 44), and has a pair of claws 221 spaced apart in the extending direction of the rod portion 230. The claws 221 protrude to the opposite side (downward) from the rod portion 230. The shape of the pressurizing jig 200 is not limited to the shape described above; any shape that can pressurize the coil wire 40 is acceptable.

[0033] As shown in Figure 11, the pressurizing jig 200 is positioned to straddle the wire arrangement section 31. The pressurizing section 44 is positioned between a pair of claws 221, and the wire straddling section 220 straddles and contacts the pressurizing section 44. Specifically, the wire straddling section 220 straddles the portion of the pressurizing section 44 where both ends of the coil wire 40 are close together or intersect when viewed from the height direction. The pressurizing jig 200 positioned on the pressurizing section 44 sinks downward due to its own weight. At this time, the sunken wire straddling section 220 may be positioned within the pressurizing jig installation hole 313, and the lower surface of the rod section 230 and the upper surface of the flat plate section 315 may or may not be in contact. The weight of the pressurizing jig 200 is transmitted to the pressurizing section 44 that is in contact with the wire straddling section 220, causing the pressurizing section 44 to be pressed downwards. At this time, the pressurizing section 44 is held between the pair of claws 221, 221, so that the pressurizing jig 200 is stably positioned on the coil wire 40. Furthermore, the distance between the pair of inner end faces 212 (see Figure 10) of the pressure jig 200 is greater than or equal to the width of the flat plate portion 315. Preferably, the distance between the inner end faces 212 of the pressure jig 200 is equal to the width of the flat plate portion 315, so that when the pressure jig 200 is placed over the coil wire 40, the outer end face 315b of the flat plate portion 315 and the inner end face 212 of the pressure jig 200 come into contact. This makes it easy to position the pressure jig 200 when it is placed over the wire arrangement portion 31, and also effectively prevents the pressure jig 200 from shifting while it is placed over the wire arrangement portion 31.

[0034] By applying pressure to the pressurizing section 44 toward the base 30, the coil wire 40 bends toward the base 30, i.e., downward. As a result, the pad-mounted portion 42 approaches the pad portion 331 and makes contact with the solder 50 that has been pre-applied on the pad portion 331 while being pressed against it. More specifically, as shown in Figure 8, the coil wire 40 is pressed against the slope 51 of the brazing material 50 (solder 50). Specifically, the coil wire 40 is pressed against the slope 51 on the outer side of the peak 52 of the mountain-shaped solder 50. More specifically, as shown in Figure 7, when viewed from above, the coil wire 40 including the pad-mounted portion 42 is pushed outward and slightly curved at the portion that is in contact with the solder 50. Also, a part of the coil wire 40 including the pad-mounted portion 42 is positioned diagonally with respect to the front end direction when viewed from above, as shown in Figure 7. Therefore, the coil wire 40, including the pad portion 42, is also spread outwards toward the rear end at the portion that is in contact with the solder 50. In other words, as shown in Figure 7 when viewed from above, the pad portion 42 is bent outwards and toward the rear end along the slope of the solder 50. In summary, the coil wire 40 not only applies a downward resistance force to the solder 50, but also an inward and forward resistance force. In other words, the coil wire 40 applies a resistance force (resistance force T (see Figure 8)) to the inclined surface 51 of the solder 50, while pressing it toward the center of the pad portion 331. By pressing the coil wire 40 against the slanted surface 51 of the solder 50 in this manner, the direction of pressure applied by the coil wire 40 to the solder 50 can be controlled to be constant. Furthermore, because the coil wire 40 contacts the slanted surface 51 of the solder 50 rather than the apex 52 of the solder 50, it is prevented from the coil wire 40 unexpectedly shifting in the left-right, front-back, and rear directions on the solder 50.

[0035] As shown in Figure 9, the upper surface 333a of the circuit body 333 is positioned lower than the upper surface 33a of the circuit section 33. More specifically, the upper surface 333a of the circuit body 333 is positioned lower than the upper surface 33a of the circuit section 33, which is positioned towards the rear end of the circuit body 333. As described above, the height from the upper surface 333a of the circuit body 333 to the upper surface 33a of the circuit section 33 (base height h2) is greater than the thickness of the pad section 331. Since the upper surface 333a of the circuit body 333 is positioned lower than the upper surface 33a of the circuit section 33, when the coil wire 40 is pressed downward, the coil wire 40 contacts the upper surface 33a on the rear end side of the circuit section 33, but does not contact the surface of the pad section 331 or the circuit section 33. This prevents the surface of the pad section 331 or the circuit section 33 from being damaged by the coil wire 40. Furthermore, the base height h2 is smaller than the height (solder height h1) to the highest point of the solder 50 relative to the upper surface 333a of the circuit body 333. Preferably, the base height h2 is half or less of the solder height h1. This allows the height of the pad portion 42 relative to the solder 50 to be adjusted to any position. That is, by pressing the coil wire 40 against the middle part of the slope 51 of the solder 50, the coil wire 40 can be sufficiently immersed in the solder 50 when the solder 50 melts, as will be described later.

[0036] After the wire placement process is completed, the melting process is carried out. In the melting process, as described above, a laser (not shown) is irradiated onto the solder 50 supplied onto the pad portion 331 from above. In this embodiment, a carbon dioxide laser is irradiated onto the solder 50. Here, "on top of the pad portion 331" includes the surface of the pad portion 331 and the space above the pad portion 331. That is, when a laser is irradiated onto the brazing material 50 supplied onto the pad portion 331, it is not limited to irradiating the solder 50 that has formed and solidified on the surface of the pad portion 331. As will be described later, it also includes irradiating solder 50 such as solder wire placed above the pad portion 331 with a laser. The heat applied from the laser melts the solder 50. The laser only needs to be shone on the solder 50, and it is not necessary for the coil wire 40 to be shone with the laser or not.

[0037] In this embodiment, during the melting process, the solder 50 is supplied to the surface of the pad portion 331 with a thickness equal to or greater than the diameter of the coil wire 40. In this embodiment, the solder 50 is initially formed with a thickness equal to or greater than the diameter of the coil wire 40, but even after melting by the laser, the thickness of the solder 50 is maintained to be equal to or greater than the diameter of the coil wire 40. As will be described later, when solder 50 is supplied by solder wire or the like during the melting process, the thickness of the melted solder 50 applied to the surface of the pad portion 331 is equal to or greater than the diameter of the coil wire 40. By applying the solder 50 to the surface of the pad portion 331 in this manner to a sufficient thickness, the coil wire 40 will be sufficiently immersed in the solder 50 during the removal process described later.

[0038] In this embodiment, during the melting process, the temperature of at least one of the coil wire 40 or the brazing material 50 (solder 50) is measured, and the amount of laser irradiation is controlled so that the temperature is within a predetermined range higher than the melting point of the brazing material 50. Alternatively, the amount of laser irradiation is controlled so that the temperature is within a predetermined range higher than the decomposition temperature of the insulating film 46. The temperature of the coil wire 40 alone, the solder 50 alone, or both the coil wire 40 and the solder 50 may be measured. More specifically, the temperature of the solder 50 irradiated with the laser, or a portion of the coil wire 40 and a length region near it immersed in the solder 50, is measured. The temperature measurement is preferably performed non-contact with respect to the solder 50, and an infrared radiation thermometer is an example of a measuring instrument used for temperature measurement. Here, the lower limit of the predetermined range is the melting point of the solder 50, preferably higher than the melting point of the insulating film 46, and more preferably higher than the decomposition temperature of the insulating film 46. The upper limit of the predetermined range can be the lower limit of the temperature at which the insulating film 46 of the coil wire 40 that is not immersed in the solder 50 (the external region described later) burns or decomposes and denatures. If the temperature of the measurement site falls outside a predetermined range, the laser dose is immediately changed. Controlling the laser dose here includes increasing the laser dose when the temperature of the measurement site is below a predetermined range, and decreasing the laser dose or interrupting laser irradiation when the temperature of the measurement site is above a predetermined range. By controlling the laser irradiation in this way, the solder 50 can be sufficiently melted, and the temperature can be raised high enough to remove the insulating film 46 in the removal process described later. In addition, it is possible to prevent the deterioration of the insulating film 46 that covers the external region of the coil wire 40, as described later.

[0039] After the melting process is performed, the removal process is carried out. When the solder 50 melts and becomes liquid, a portion of the coil wire 40 that was pressed against the solder 50 is immersed in the molten solder 50. As described above, the coil wire 40, which was pressed against the center of the pad portion 331, penetrates into the solder 50 towards the center of the pad portion 331. Specifically, as shown in Figure 8, when viewed in the front-to-back direction, the coil wire 40 (especially the portion positioned above the pad portion 42) that is pressed against the inclined surface 51 of the solder 50 penetrates into the solder 50 while moving inward and downward (coil wire 40a towards the lower right and coil wire 40b towards the lower left). Also, as shown in Figure 7, when viewed from above, the coil wire 40 penetrates into the solder 50 while moving inward and towards the front end (coil wire 40a towards the lower right of the paper and coil wire 40b towards the lower left of the paper). In other words, the molten solder 50 encases the coil wire 40 from the central side of the pad portion 331. Specifically, in Figure 8, solder 50a encases the coil wire 40 from the lower right of coil wire 40a, and solder 50b encases the coil wire 40b from the lower left of coil wire 40b. As a result, as will be described later, a portion of the side surface 40e of coil wire 40b (see Figure 5) (the upper right portion of the page) is placed outside the solder 50b. Alternatively, as with coil wire 40a, a portion of coil wire 40 is completely immersed in the solder 50.

[0040] When the coil wire 40 is immersed in the molten solder 50, the liquid solder 50 piled on the surface of the pad portion 331 tends to spread laterally (left-right and front-back directions). In this embodiment, the solder 50 spreads only on the surface of the pad portion 331, which has good wettability, and does not spread beyond the pad portion 331. As described above, when viewed from above, the coil wire 40 moves inward and toward the front end as it enters the interior of the solder 50. This causes the solder 50 to spread out particularly inward and toward the front end. On the other hand, as described above, the pad portion 331 has a rectangular shape with the inner and front corners cut off when viewed from above. This prevents the solder 50 from spreading excessively flat when the coil wire 40 is immersed in the solder 50, as the solder tends to spread inward and towards the front. Furthermore, the solder 50, which is prevented from spreading, rises upward and tries to cover the coil wire 40, so that the upper circumferential surface 40c of the coil wire 40 (see Figure 5) is covered with solder 50. As a result, the coil wire 40 can be sufficiently immersed in the solder 50. As mentioned above, the solder 50 does not easily wet and spread onto the upper surface 333a of the circuit body 333, which is not metal-plated, and therefore rises upward on the pad portion 331. The raised solder 50 becomes rounded due to surface tension, and as shown in Figure 4, when viewed from above, the solder 50 may appear to be positioned outside the pad portion 331.

[0041] When the coil wire 40 is immersed in the solder 50, which has been heated to a high temperature by laser irradiation, the insulating film 46 on the surface of the coil wire 40 immersed in the solder 50 is heated by the heat of the molten solder 50. As a result of this heating, the insulating film 46 in contact with the solder 50 is removed. Specifically, for example, the insulating film 46 is decomposed and removed from the coil wire 40. When the temperature of the insulating film 46 reaches its decomposition temperature, the insulating film 46 decomposes. The affinity between the coil core 47, which is made of metal or the like, and the solder 50 is greater than the affinity between the decomposition products of the insulating film 46, which is made of resin or the like, and the coil core 47. As a result, the solder 50 wets the surface of the coil core 47, and the decomposition products of the insulating film 46 are removed from the surface of the coil core 47 to the outside of the solder 50. The decomposition products of the insulating film 46 precipitate on the surface of the solder 50. Alternatively, the decomposition products of the insulating film 46 sublimate due to the heat of the molten solder 50. In this way, the insulating film 46 is decomposed and removed from the surface of the coil wire 40, exposing the coil core 47. Alternatively, instead of the insulating film 46 being decomposed, the insulating film 46 may melt and be removed from the coil wire 40. When the temperature of the insulating film 46 reaches the melting point of the resin forming the insulating film 46, the insulating film 46 melts and its fluidity increases, becoming liquid. The solder 50 wetting the surface of the coil core 47 pushes the liquid insulating film 46 off the surface of the coil core 47 and removes it. The liquid insulating film 46 floats to the surface of the solder 50. Alternatively, a portion of the insulating coating 46 may melt and another portion may decompose and be removed from the coil wire 40.

[0042] To adequately remove the insulating coating 46, a coil wire 40 with a low heat resistance insulating coating 46 may be used. Examples include insulating materials with a heat resistance of 120 degrees Celsius or less, such as polyurethane. Furthermore, it is preferable to use a coil wire 40 with an insulating coating 46 that is sufficiently thin so that it is easy to remove. Furthermore, the insulating film 46 is preferably transparent or white and uncolored. This keeps the laser absorption rate of the insulating film 46 low, preventing the insulating film 46 from being directly peeled off by laser irradiation, or preventing the insulating film 46 that is not covered by the solder 50 from being altered by laser irradiation.

[0043] In this way, almost all of the insulating film 46 covered with solder 50 is removed from the coil wire 40, but this is not limited to the removal of the insulating film 46. Some insulating film 46 may remain on a portion of the coil wire 40 immersed in solder 50. For example, as shown in Figure 4, a portion of the internal region (the region inside the first boundary line 48) covered with solder 50b is also a covered portion 473, which will be described later, where insulating film 46 remains. This is because the heat from solder 50b is not sufficiently transferred to the peripheral portion of the internal region (the portion close to the first boundary line 48). Also, as will be described later, a very small amount of insulating film 46 may remain in the central part of the internal region without being completely decomposed or melted. Furthermore, a portion of the outside of the solder 50 on the coil wire 40 does not need to be covered by the insulating film 46. For example, in the external region of the coil wire 40a shown in Figure 4, a portion of the insulating film 46 adjacent to the solder 50a has been removed, becoming an exposed portion 471, which will be described later. This is because the heat from the molten solder 50 is also transferred to the insulating film 46 that is outside the solder 50 and adjacent to it.

[0044] When the insulating film 46 is removed from the coil wire 40, the coil core 47 and the solder 50 come into contact. The metal constituting the coil core 47 and the metal constituting the solder 50 form an alloy, thereby joining the coil wire 40 and the pad portion 331. The molten solder 50 cools and solidifies.

[0045] In this embodiment, the melting process and the removal process are performed at overlapping timings. Overlapping timings mean that all of the processes may be performed at the same time, or parts of them may be performed simultaneously. Specifically, when the solder 50 begins to melt in the melting process, the removal process begins and the coil wire 40 begins to be immersed in the solder 50. That is, the solder 50 is melted by the laser while the coil wire 40 is immersed in the solder 50. The melting process is completed before the removal process is finished. In this embodiment, the coil wire 40 is continuously pressurized toward the base before and during laser irradiation. That is, the pressurization in the wire placement process and part of the melting process are performed at overlapping timings. As a result, the coil wire 40 is immersed at the same time as the solder 50 melts.

[0046] In this embodiment, during the melting process, an inert gas (not shown) is supplied to the brazing material 50 (solder 50) in the direction of pressurizing the coil wire 40. It is also preferable to supply the inert gas in the removal process immediately following the melting process. The direction in which the inert gas is supplied is preferably substantially parallel to the direction in which the coil wire 40 is pressurized. That is, during the melting process, the inert gas is supplied to the solder 50 from above. As the inert gas, a gas with low reactivity with the solder 50 is used, and noble gases such as nitrogen and argon are examples. By supplying an inert gas to the solder 50, the oxygen-containing air surrounding the solder 50 can be removed. This prevents the solder 50 from oxidizing, resulting in good wettability of the solder 50 on the circumferential surface of the coil wire 40 and on the surface of the pad portion 331. Furthermore, by supplying inert gas along the direction in which the coil wire 40 is pressurized, oxygen around the solder 50 can be sufficiently removed over a wide area. That is, since the solder 50 is piled up in a mountain-like shape so as to protrude upward, supplying inert gas from above ensures that the inert gas is supplied to the entire surface of the slope 51 of the solder 50. Instead of supplying inert gas in the direction that pressurizes the coil wire 40, the inert gas may be supplied in each direction of the resistance force that the coil wire 40 exerts on the solder 50. That is, the inert gas may be supplied from two directions: from the upper right toward the solder 50, and from the upper left toward the solder 50. This ensures that the inert gas is sufficiently supplied around the coil wire 40, especially when it is embedded in the solder 50. The wettability of the solder 50 on the circumferential surface of the coil wire 40 is maintained well, and the coil wire 40 is sufficiently immersed in the solder 50.

[0047] This method includes a cutting step that is performed after the pad portion 331 and the coil wire 40 are joined with a brazing material 50 (solder 50) in the removal step. In the cutting step, the coil wire 40 and the base 30 are cut, and a portion of the coil wire 40 including one end (fixing portion 43) and a portion of the base 30 including the wire fixing portion 312 are removed. In this embodiment, the coil wire 40 and the base 30 are cut in a plane substantially perpendicular to the front-to-back direction. Preferably, the coil wire 40 and the base 30 are cut in the same plane. Specifically, the coil wire 40 and the base 30 are cut at the cross-section indicated by the dashed line Y in Figure 9. That is, in this embodiment, the cross-section that cuts the coil wire 40 and the base 30 is located on the rear end side of the side end face 333b of the circuit body 333 and is parallel to that face. More specifically, the cross-section includes the installation hole 334. Alternatively, the cut surface may be on the same plane as the side end surface 333b of the circuit body 333. Furthermore, in the removal process, the circuit section 33 may not be cut, but only the flat plate section 315 of the wire arrangement section 31 and the coil wire 40 may be cut. In this case, the cut surface may be on the same plane as the rear end side surface 33d located on the rear end side of the circuit section 33 (the interface between the wire arrangement section 31 and the circuit section 33).

[0048] Both ends of the coil wire 40, which is positioned on the front side of the cut surface, are removed. Specifically, the ends of the coil wire 40, including the pressurized portion 44, the bent portion 45, and the fixing portion 43, are removed. In addition, a portion of the base 30, which is positioned on the front side of the cut surface, is also removed. Specifically, the ends of the base 30, including the wire arrangement portion 31, are removed.

[0049] The antenna device 100 is manufactured through the above process. In manufacturing the antenna device 100, the melting step of melting the solder 50 by laser irradiation and the step of immersing the coil wire 40 in the molten solder 50 to remove a portion of the insulating coating 46 from the coil wire 40 are essential steps. The inclusion of other steps or other components is optional. According to this method, when the coil wire 40 is immersed in solder 50 for soldering, the insulating coating 46 is removed from the coil wire 40. In other words, this method allows the insulating coating 46 to be removed during the brazing process, eliminating the need to remove the insulating coating 46 from the coil wire 40 before the brazing process. This reduces the manufacturing time of the antenna device 100.

[0050] (Details of the antenna device) Next, the features of the antenna device 100 manufactured according to this embodiment will be described in detail. The coil wire 40 has an exposed portion 471 in which the coil core 47 is exposed from the insulating coating 46. On the circumferential surface of the coil wire 40, a first boundary line 48, which is the boundary between the internal region embedded in the solder 50 and the external region that is outside the solder 50, and a second boundary line 472, which is the boundary between the exposed portion 471 and the coated portion 473 of the coil wire 40 that is covered by the insulating coating 46, are aligned with each other.

[0051] When it is said that a portion of the circumferential surface of the coil wire 40 is embedded in the solder 50, it means that a portion of the circumferential surface of the coil wire 40 is covered with solder 50. The internal region is a portion of the coil wire 40's surface that is embedded in the solder 50, and is the region inside the first boundary line 48 (see Figure 4). The external region is a portion of the coil wire 40's surface that is not covered by the solder 50, and is the region outside the first boundary line 48. As shown in Figure 4, two first boundary lines 48 are arranged on the circumferential surface of the coil wire 40a, spaced apart in the front-to-back direction. Each first boundary line 48 on the coil wire 40a encircles the coil wire 40a once. Here, the internal region (the region inside the first boundary lines 48) is a portion of the circumferential surface of the coil wire 40a sandwiched between the pair of first boundary lines 48. That is, the internal region of the coil wire 40a extends over the entire radial direction of the coil wire 40a. On the other hand, a roughly elliptical first boundary line 48 is positioned on the circumferential surface of the coil wire 40b shown in Figure 4. The internal region of the coil wire 40b is the roughly elliptical region inside the first boundary line 48. More specifically, the internal region of the coil wire 40b covers a portion of the lower circumferential surface of the coil wire 40b (the lower circumferential surface 40d, which will be described later), and extends only to a portion of the radial direction of the coil wire 40b.

[0052] The exposed portion 471 is a part of the circumferential surface of the coil wire 40 that is not covered by the insulating film 46 and in which the coil core 47 is exposed. As described above, the insulating film 46 may not be sufficiently removed during the removal process, and a small amount of the insulating film 46 may remain in the central part of the internal region. That is, the insulating film 46 may be located in a very small part of the central part of the exposed portion 471. In this case, the area where the insulating film 46 is located on the inside, excluding the periphery of the internal region, is also considered the exposed portion 471. Preferably, the insulating film 46 is completely removed from the entire area of ​​the exposed portion 471. On the other hand, a portion of the circumferential surface of the coil wire 40, excluding the exposed portion 471, is covered with an insulating film 46. The portion of the circumferential surface of the coil wire 40 covered with the insulating film 46 is referred to as the covered portion 473. In the coil wire 40a, the exposed portion 471 extends around the entire circumference of the coil wire 40a. The exposed portion 471a is the region sandwiched between a pair of second boundary lines 472a, 472a that are spaced apart in the front-rear direction. Each of the second boundary lines 472a encircles the circumferential surface of the coil wire 40a. In the coil wire 40b, the exposed portion 471b is approximately elliptical in shape, including a part of the lower circumferential surface 40d (described later), and extends only over a portion of the coil wire 40b in the radial direction. That is, the exposed portion 471b is the region inside the approximately elliptical second boundary line 472.

[0053] As shown in Figure 4, the exposed portion 471 and the internal region substantially coincide, but they do not need to coincide perfectly. For example, the exposed portion 471 may include the external region, and the internal region may include the covering portion 473. In the coil wire 40a, most of the exposed portion 471 is covered by the solder 50 and coincides with the internal region, but a part of the exposed portion 471 is outside the solder 50 and is the external region. In the coil wire 40b, most of the internal region is the exposed portion 471 of the coil core 47, but a part of the remaining internal region is the covering portion 473 covered by the insulating film 46.

[0054] Here, the statement that the first boundary line 48 and the second boundary line 472 are aligned means that the convex portions and concave portions of the first boundary line 48 and the second boundary line 472 correspond to each other. In other words, the shape of the first boundary line 48 and the shape of the second boundary line 472 are substantially identical. Preferably, the acute angle between a tangent to a part of the first boundary line 48 and a tangent to a part of the second boundary line 472 adjacent to that part of the first boundary line 48 is smaller than the acute angle between the plane perpendicular to the extending direction of the coil wire 40 and the first boundary line 48. Furthermore, it is desirable that the first boundary line 48 and the second boundary line 472 are sufficiently close to each other. Specifically, it is preferable that the distance between a portion of the first boundary line 48 and a portion of the second boundary line 472 adjacent to that portion is less than or equal to the wire diameter of the coil. More preferably, the distance between a portion of the first boundary line 48 and a portion of the second boundary line 472 adjacent to that portion is zero, and the first boundary line 48 and the second boundary line 472 are approximately coincident.

[0055] Furthermore, the first boundary line 48 may be located inside or outside the exposed portion 471. For example, in solder 50a, the first boundary line 48a is located on the exposed portion 471a, that is, it is located closer to the inside of the exposed portion 471a than the second boundary line 472a. On the other hand, in solder 50b, a portion of the length of the first boundary line 48 (first boundary line 48b) is located outside the exposed portion 471b, that is, it is located further out of the exposed portion 471b than the second boundary line 472b. Also, another portion of the length of the first boundary line 48 in solder 50b (first boundary line 48c) approximately coincides with a portion of the second boundary line 472 (second boundary line 472c). Furthermore, the second boundary line 472 and the first boundary line 48 may intersect. That is, a portion of the length of the first boundary line 48 may be located outside the exposed portion 471, and another portion of the length of the first boundary line 48 may be located inside the exposed portion 471, and the second boundary line 472 and the first boundary line 48 may intersect.

[0056] By shaping the solder 50 to enclose the coil wire 40 so that it follows the first boundary line 48 and the second boundary line 472, the antenna device 100 can be manufactured by the manufacturing method described above. In other words, the antenna device 100 of this embodiment has a structure that can be manufactured with fewer manufacturing steps. Furthermore, because the first boundary line 48 and the second boundary line 472 are aligned with each other, almost the entire area of ​​the exposed portion 471 is covered with solder 50, and the area of ​​the exposed portion 471 that is not covered with solder 50 (the area where the coil core is exposed) can be minimized. This prevents the coil core 47 from being exposed more than necessary, and improves the insulation of the coil wire 40. In addition, because the exposure of the coil core 47 is reduced, deterioration of the coil core 47 due to wear and oxidation can be prevented. Furthermore, an antenna device 100 in which the coil wire 40 is embedded in the solder 50 so that the first boundary line 48 and the second boundary line 472 are aligned can be manufactured without following the manufacturing method described above. For example, one example is to remove the insulating coating while pre-masking the circumferential surface of the coil wire 40 other than the area to be covered by the solder 50.

[0057] In this embodiment, the thickness (length in the height direction) of the brazing material 50 (solder 50) is greater than the wire diameter of the coil wire 40. Here, the thickness of the solder 50 refers to the maximum height of the solder 50 relative to the surface of the pad portion 331 at a point in the region where the solder 50 is located and does not overlap with the coil wire 40 when viewed in the height direction. In other words, the thickness of the solder 50 here refers to the thickness of the solder 50 only, excluding the thickness of the coil wire 40. For example, as shown in Figure 5, the solder 50 is formed in a roughly mountain-like shape with the peak above the coil wire 40. In this case, the highest point of the solder 50 is above the coil wire 40, but the thickness of the solder 50 is smaller than the height of the solder 50 (distance from the surface of the pad portion 331 to the highest point of the solder 50). In this case, the thickness of the solder 50 is the height of the solder 50 at a point close to the side of the coil wire 40.

[0058] Since the solder 50 is formed with a sufficient thickness greater than or equal to the diameter of the coil wire 40, the coil wire 40 can be fully immersed in the solder 50 in the manufacturing method of the antenna device 100 described later. Furthermore, because the solder 50 is applied to a thickness greater than or equal to the diameter of the coil wire 40, almost the entire radial length of the coil wire 40 can be embedded in the solder 50. This results in a physically strong joint between the solder 50 and the coil wire 40, or a good electrical connection between the solder 50 and the coil wire 40.

[0059] In this embodiment, in a portion of the length of the coil wire 40b (a buried portion 42a which is a portion of the length of the coil wire 40 having an exposed portion 471 when viewed from the radial direction), a portion in the radial direction is an exposed portion 471, and the other portion in the radial direction is a covered portion 473. The statement that a portion in the radial direction is an exposed portion 471 and the other portion is a covered portion 473 means that, in a cross-section at a certain point in the buried portion 42a, a portion of the circumference (arc) of the circle in the cross-section is not covered by the insulating film 46, exposing the coil core 47, while the other portion of the circumference is covered by the insulating film 46. In this embodiment, as shown in Figures 4 and 5, the coil wire 40b has a radial portion exposed 471 and another portion covered 473 throughout the entire area of ​​the buried portion 42a. In other words, the insulating film 46 is not divided by the exposed portion 471. In other words, the first insulating coating 46a and the second insulating coating 46b, which cover the entire radial region of the first and second length regions of the coil wire 40, flanking the embedded portion 42a (a portion of the length embedded in the brazing material 50), are connected by a bridge portion 461 that has a width smaller than the diameter of the coil wire 40 and extends along the direction in which the coil wire 40 extends. Here, the first length region and the second length region are external regions of the brazing material 50, and are a portion of the length of the coil wire 40 that is located on the front end side or rear end side of the pad portion 331 when viewed in the height direction, respectively. As shown in Figure 4, the first insulating coating 46a covers the entire circumference of the coil wire 40 (first length region) located on the front end side of the buried portion 42a. The second insulating coating 46b covers the entire circumference of the coil wire 40 (second length region) located on the rear end side of the buried portion 42a. The bridge portion 461 connecting the first insulating film 46a and the second insulating film 46b is located on the circumferential surface of the buried portion 42a. The bridge portion 461 is part of the insulating film 46, is narrow in width, and is elongated in the direction along the axial direction of the coil wire 40. The longitudinal direction of the bridge portion 461 and the extending direction of the coil wire 40 are aligned with each other. Here, the width of the bridge portion 461 refers to the minimum length of the bridge portion 461 in the circumferential direction. Furthermore, the statement that the longitudinal direction of the bridge portion 461 and the extending direction of the coil wire 40 are aligned with each other means that the acute angle of the angle formed when a virtual center line connecting the centers of the width direction of the bridge portion 461 is projected onto the axis of the coil wire 40 is at least 30 degrees or less. Preferably, the center line of the bridge portion 461 and the axis of the coil wire 40 are substantially parallel.

[0060] Furthermore, in this embodiment, in a portion of the coil wire 40's length (embedded portion 42a), the upper portion (upper circumferential surface 40c) opposite to the side where the pad portion 331 is located, and the lower portion (lower circumferential surface 40d) facing the pad portion 331, are exposed portions 471 from which the insulating coating 46 has been removed and are in contact with the brazing material 50. In addition, a portion of the lateral side of the length portion is a covered portion 473 covered with the insulating coating 46 and is not in contact with the brazing material 50. Here, the upper circumferential surface 40c is a region of a predetermined width on the circumferential surface of the embedded portion 42a that includes the upper end of the coil wire 40, as shown in Figure 5. That is, the upper circumferential surface 40c may be a substantially linear region including only the upper end of the coil wire 40, or it may be an elongated region including the upper end of the coil wire 40 and its vicinity. The lower circumferential surface 40d is a region of a predetermined width on the circumferential surface of the embedded portion 42a that includes the lower end of the coil wire 40. Similar to the upper circumferential surface 40c, the lower circumferential surface 40d may be a substantially linear region including only the lower end, or it may be an elongated shape with width. The width of the upper circumferential surface 40c or the lower circumferential surface 40d may be half or less of the wire diameter of the coil wire 40, or it may be more than half. Here, when we say that a portion of the side of the coil wire 40 is the covering portion 473, we mean that at least a portion of the side surface is the covering portion 473. The side surface 40e is the region of the coil wire 40's circumferential surface excluding the upper surface 40c and the lower surface 40d. Furthermore, in this embodiment, a portion of the upper side of a certain length region (buried portion 42a) of the coil wire 40 is covered with an insulating coating 46, forming a covered portion 473 that is not in contact with the brazing material 50, while the entire lower side of the certain length region (buried portion 42a) is an exposed portion 471 from which the insulating coating 46 has been removed, and is in contact with the brazing material 50. That is, the outer and upper region of the side circumferential surface 40e is the covered portion 473, and the lower region of the side circumferential surface 40e is the exposed portion 471. Here, the upper side of the side circumferential surface 40e is the region located above the center of the cross-section of the coil wire 40, and the lower side of the side circumferential surface 40e is the region located below this center of the cross-section and facing the pad portion 331. The upper circumferential surface 40c and the lower circumferential surface 40d are not limited to being exposed portions 471 over the entire length of the embedded portion 42a. In some length of the embedded portion 42a, the upper circumferential surface 40c or the lower circumferential surface 40d may be exposed portions 471, while in the remaining length, the upper circumferential surface 40c or the lower circumferential surface 40d may be covered portions 473.

[0061] By embedding only a portion of the radial coil wire 40 in the solder 50 and leaving the other portion outside the solder 50, the coil wire 40 and the pad portion 331 can be joined with a small amount of solder 50. Furthermore, since a portion of the radial direction not covered by the solder 50 is covered by the insulating film 46, the coil core 47 of the embedded portion 42a is covered by the insulating film 46 or solder 50 around its entire circumference. As a result, the coil core 47 is not exposed to the outside, preventing deterioration and breakage of the coil core 47 due to oxidation, wear, etc. Furthermore, because a portion of the radial direction of the embedded portion 42a is not covered by the solder 50 along its entire length, the heat fatigue resistance characteristics of the joint between the pad portion 331 and the coil wire 40 are improved. For example, when the coil wire 40 is immersed in molten solder 50, air adhering to the coil wire 40 may enter the interior of the solder 50. In contrast, according to this embodiment, because a portion of the radial direction of the coil wire 40 is not covered by the solder 50 along the entire length of the embedded portion 42a, any air that enters the solder 50 can easily move upward along the surface of the coil wire 40 and escape from the solder 50. This suppresses the formation of voids inside the solder 50, and prevents deterioration of the joint over time due to the contraction and expansion of air inside the solder 50 in response to temperature changes around the joint. Furthermore, by covering the upper circumferential surface 40c of the coil wire 40 with the brazing material 50, the upper circumferential surface 40c, which is prone to wear due to interference with other components, can be protected by the brazing material 50.

[0062] As shown in Figure 4, the embedded portion 42a of the coil wire 40a embedded in the solder 50a has an exposed portion 471 over its entire radial length where the insulating coating 46 has been removed. In this embodiment, both ends of the embedded portion 42a protrude from the solder 50a at an angle to the circumferential direction of the coil wire 40a. The first insulating coating 46a covering the first length region of the coil wire 40a on the front end side of the embedded portion 42a and the second insulating coating 46b covering the second length region on the rear end side of the embedded portion 42a are separated from each other by the exposed portion 471. Furthermore, at both ends of the embedded portion 42a, only a portion in the radial direction is an internal region covered by the solder 50, while the other portion in the radial direction is an external region not covered by the solder 50. In this embodiment, at both ends of the buried portion 42a, the area of ​​the outer surface of the coil wire 40a that is close to the solder 50a is an exposed portion 471a where the insulating coating 46 has been peeled off. Alternatively, the area of ​​the outer surface of the coil wire 40a that is close to the solder 50a may be covered with the insulating coating 46 to form a covered portion 473. That is, the second boundary line 472 and the first boundary line 48 may substantially coincide, or the second boundary line 472 may be located inside the exposed portion 471. In this case, at both ends of the buried portion 42a, a part in the radial direction is covered with solder 50, and the other part in the radial direction is covered with insulating coating 46. This prevents the coil core 47 from deteriorating and breaking due to oxidation, wear, etc., at both ends of the buried portion 42a, as described above. In this embodiment, a configuration is shown in which, in only one of the left and right coil wires 40a, 40b, a portion of the radial direction of the entire length of the buried portion 42a is exposed 471 and the other portion is covered 473, but the embodiment is not limited to this. In both the left and right coil wires 40a, 40b, a portion of the radial direction of the entire length of the buried portion 42a may be exposed 471 and the other portion may be covered 473. In addition, in both the left and right coil wires 40a, 40b, the entire radial direction of a portion of the length may be exposed 471.

[0063] Furthermore, in this embodiment, as shown in Figures 2 and 3, the end faces 41 at both ends of the coil wire 40 and the side end face 33b of the base 30 (circuit section 33) are arranged on the same plane. Here, the end face 41 of the coil wire 40 is the cross-section created when the coil wire 40 is cut in the cutting process described later. In this embodiment, since the coil wire 40 is arranged diagonally with respect to the cut surface, the end face 41 of the coil wire 40 is elliptical. Also, here, the side end face 33b of the circuit section 33 is the surface facing the rear end of the circuit section 33, and is the cross-section created when the base 30 is cut in the cutting process described above. In other words, the side end face 33b of the circuit section 33 is on the same plane as the surface indicated by the dashed line Y in Figure 9. Alternatively, in the cutting process, the coil wire 40 and the circuit section 33 may be cut along the side end face 333b of the circuit body 333. In this case, the end face 41 of the coil wire 40, the side end face 33b of the circuit section 33, and the side end face 333b of the circuit body 333 are all arranged on the same plane. Alternatively, in the cutting process, the base 30 may be cut on the same plane as the interface between the circuit section 33 and the wire arrangement section 31 (the same plane as the rear end side surface 33d in Figure 9). By ensuring that the coil wire 40 and the circuit body 333 do not protrude beyond the rear end of the side end face 33b of the circuit section 33, deterioration due to wear is prevented.

[0064] <Variation> It should be noted that the present invention is not limited to the embodiments described above, and includes various modifications, improvements, and other forms as long as the objectives of the present invention are achieved. The following variations can be combined as appropriate.

[0065] For example, in this embodiment, the solder 50 was pre-formed into a mountain shape on the surface of the pad portion 331 and solidified, but this is not limited to this. It is not necessary to pre-form the solder 50 on the surface of the pad portion 331. For example, as described above, in the melting process, the solder 50 supplied above the pad portion 331 may be melted by a laser, and the molten solder 50 may fall onto the surface of the pad portion 331. If the solder 50 is not pre-formed on the surface of the pad portion 331 and the molten solder 50 is applied to the surface of the pad portion 331 in the melting process, the wire placement process may be performed after the melting process. That is, after supplying liquid solder 50 onto the surface of the pad portion 331, the coil wire 40 may be placed above the pad portion 331, and the coil wire 40 may be pressed downwards to immerse the coil wire 40 in the solder 50. In other words, the melting process and the removal process may be performed at different timings.

[0066] In this embodiment, the solder 50 is pre-formed on the pad surface with a slope 51 in an arch-shaped mountain form, but it is not limited to this. For example, the slope 51 of the solder 50 may be a straight line or concave downwards. Also, the vertex 52 of the solder 50 is not limited to a point. The highest points of the solder 50 may be connected in a line or may be a surface. For example, the solder 50 may be formed in a trapezoidal shape when viewed from the front or back direction.

[0067] In this embodiment, to press the coil wire 40 against the solder 50, one end of the coil wire 40 is fixed to the rear end of the base 30, and a pressing jig 200 is placed on the coil wire 40 to press the coil wire 40 downwards, but this is not limited to this. For example, without using a pressing jig, the coil wire 40 may be brought closer to the solder 50 and pressed against it by a mechanism that pulls or pushes the coil wire 40 downwards. Alternatively, when the coil wire 40 is pulled out towards the rear end after being positioned above the pad portion 331 in the wire placement process, the coil wire 40 may be pulled out downwards and fixed so that it presses against the solder 50.

[0068] As described above, in this embodiment, the depth (length in the height direction) of the installation hole 334 is greater than the thickness (length in the height direction) of the circuit body 333, so that the entire upper surface 33a of the circuit section 33 is positioned higher than the upper surface 333a of the circuit body 333. Alternatively, only the upper surface 33a of the circuit section 33 located on the rear end side of the circuit body 333 may be positioned higher than the upper surface 333a of the circuit body 333. For example, a protrusion is provided on the rear end side of the circuit body 333 that protrudes upward from the upper surface 33a of the circuit section 33, and the upper surface of the protrusion may be higher than the upper surface 333a of the circuit body 333. This prevents the coil wire 40, which is pressurized and approaches the pad section 331, from coming into contact with the pad section 331 and damaging it. In this case, substantially the entire upper surface 33a of the circuit section 33, excluding the protrusion, may be positioned lower than the upper surface 333a of the circuit body 333.

[0069] In this embodiment, the pressure jig installation hole 313 is located between the circuit section 33 and the support section 311, but is not limited to this. The pressure jig installation hole 313 may also be provided between the support section 311 and the wire fixing section 312. In that case, the pressure section 44 is a portion of the length region between the bent section 45 and the fixing section 43.

[0070] The above embodiment encompasses the following technical concepts. (1) A method for manufacturing an antenna device having an antenna section in which a coil wire with an insulating coating covering the coil core is wound, and a base having a pad section in which a part of the coil wire is brazed with a brazing material, A melting step in which a laser is irradiated onto the brazing material supplied on the pad portion and the brazing material melts, A method for manufacturing an antenna device, comprising a removal step of immersing the coil wire in the molten brazing material so that a portion of the insulating coating is removed from the coil wire, and the coil wire and the pad portion are joined by the brazing material. (2) A method for manufacturing the antenna device described in (1), which is performed at a timing in which part of the melting process and part of the removal process overlap. (3) The method for manufacturing an antenna device according to (1) or (2), wherein in the melting step, the brazing material is supplied to the surface of the pad portion with a thickness equal to or greater than the diameter of the coil wire. (4) In the removal step, the insulating film is decomposed and removed from the coil wire, the method for manufacturing an antenna device according to any one of (1) to (3). (5) A method for manufacturing an antenna device according to any one of (1) to (4), wherein the temperature of at least one of the coil wire or the brazing material is measured in the melting step, and the amount of laser irradiation is controlled so that the temperature is within a predetermined range higher than the melting point of the brazing material. (6) The method for manufacturing an antenna device according to (5), wherein the amount of laser irradiation is controlled so that the temperature is within a predetermined range higher than the decomposition temperature of the insulating film. (7) Further including a wire arrangement step performed prior to the melting step, The base has a wire fixing portion for fixing the coil wire, In the wire arrangement step, one end of the coil wire is fixed to the wire fixing portion, and a portion of the coil wire is placed on the brazing material provided on the surface of the pad portion. A method for manufacturing an antenna device according to any one of (1) to (6), wherein in the wire arrangement step, a pressurized portion which is a partial length region between one end and the portion of the coil wire is pressed toward the base so that the coil wire is pressed against the brazing material. (8) The method for manufacturing an antenna device according to (7), wherein in the wire arrangement step, the brazing material is formed on the surface of the pad portion in a mountain shape having a slope that slopes downward from the center to the periphery of the pad portion, and the coil wire is pressed against the slope of the brazing material. (9) The method for manufacturing the antenna device according to (8), wherein the coil wire is pressed against the slope toward the center of the pad portion. (10) A method for manufacturing an antenna device according to any one of (7) to (9), comprising a cutting step in which, after the pad portion and the coil wire are joined with the brazing material, the coil wire and the base are cut, and a portion of the coil wire including the one end and a portion of the base including the wire fixing portion are removed. (11) The base has a support portion against which the coil wire is pressed and which changes the direction in which the coil wire is pulled out, In the wire arrangement step, the bent portion located between the portion and the end of the coil wire is pressed against the support portion of the base and bent. A method for manufacturing an antenna device according to any one of (7) to (10), wherein one end of the coil wire that has been bent at the bent portion is wrapped around the wire fixing portion of the base. (12) A method for manufacturing an antenna device according to any one of (7) to (11), wherein in the melting step, an inert gas is supplied to the brazing material in the direction in which the coil wire is pressurized. (13) An antenna device having an antenna section around which a coil wire having a coil core and an insulating film covering the coil core is wound, and a base having a pad section, The coil wire has an exposed portion in which the coil core is exposed from the insulating film, The coil wire and the pad portion are joined together by a brazing material. A portion of the coil wire is embedded in the brazing material. An antenna device in which a first boundary line, which is the boundary between the internal region of the coil wire embedded in the brazing material and the external region that is outside the brazing material, and a second boundary line, which is the boundary between the exposed portion and the coated portion of the coil wire covered with the insulating film, are aligned with each other. (14) The antenna device according to (13), wherein the thickness of the brazing material is greater than the diameter of the coil wire. (15) The antenna device according to (13) or (14), wherein in a portion of the length region of the coil wire, a portion in the radial direction is the exposed portion and the other portion in the radial direction is the covered portion. (16) The antenna device according to (15), wherein in the portion of the length of the coil wire, the upper portion on the side opposite to the side where the pad portion is located and the lower portion on the side facing the pad portion are the exposed portion and are in contact with the brazing material, and the lateral portion in the portion of the length is the covered portion and is not in contact with the brazing material. (17) The antenna device according to (16), wherein a portion of the upper side of the partial length region is the covering portion and is not in contact with the brazing material, and the entire lower side of the partial length region is the exposed portion and is in contact with the brazing material. (18) The antenna device according to any one of (15) to (17), wherein the first insulating film and the second insulating film, which cover the entire radial portion of the first and second length regions of the coil wire that enclose the portion of the coil wire embedded in the brazing material, are connected by a bridge portion that has a width smaller than the diameter of the coil wire and extends along the coil wire. (19) The antenna device according to any one of (13) to (18), wherein the end faces of both ends of the coil wire and the side end face of the base are arranged on the same plane. (20) Both ends of the coil wire are joined to each of the pair of pad portions provided on the base by the brazing material, Each of the pair of pad portions is formed in a rectangular shape. Each of the aforementioned rectangles has a shape in which one of the inner corners of the pair of pad portions is chamfered to form a slanted edge. The antenna device according to any one of (13) to (19), wherein the hypotenuse is aligned with the direction of extension of the coil wire. (21) An antenna device in which the insulating coating is transparent or white in color. [Explanation of Symbols]

[0071] 100 Antenna equipment 20 Antenna section 21 cores 30 base 31 Wire arrangement section 311 Support part 312 Wire fixing part 313 Pressure jig installation hole 314 Hole 315 Flat plate part 315a top side 315b Outer end face 316 Core insertion hole 316a Chamfered section 33 Circuit section 33a Top side 33b Side end face 33c slope 33d rear end side 331 Pad section 331a hypotenuse 333 Circuit body 333a top side 333b Side end face 334 Installation hole 335 Guide section 335a External surface 40, 40a, 40b coil wire 40c Upper surface 40d Lower surface 40e Side surface 41 End face 42 Upper placement section of the pad 42a Buried part 43 Fixed part 44 Pressurized section 45 Bends 46 Insulating coating 46a First insulating coating 46b Second insulating film 461 Hashibe 47 Coil core 471, 471a, 471b Exposed part 472, 472a, 472b, 472c second border 473 Covering part 48, 48a, 48b, 48c first boundary line 49 Coil section 50 Brazing material 50, 50a, 50b solder 51 Slope 52 vertices 200 Pressurizing fixtures 210 Arm 211 Weight section 212 Inner end face 220 Wire straddling section 221 Nails 230 Rod section

Claims

1. A method for manufacturing an antenna device having an antenna section in which a coil wire, whose coil core is covered with an insulating film, is wound, and a base having a pad section in which a part of the coil wire is brazed with a brazing material, A melting step in which a laser is irradiated onto the brazing material supplied on the pad portion and the brazing material melts, A removal step in which the coil wire is immersed in the molten brazing material, a portion of the insulating film is removed from the coil wire by the heat of the brazing material, and the coil wire and the pad portion are joined by the brazing material, This includes a wire arrangement step performed before the melting step, The base has a wire fixing portion for fixing the coil wire, In the wire arrangement step, one end of the coil wire is fixed to the wire fixing portion, and a portion of the coil wire is placed on the brazing material provided on the surface of the pad portion. A method for manufacturing an antenna device, wherein in the wire arrangement step, a pressurized portion, which is a portion of the length between one end and the part of the coil wire, is pressed toward the base so that the coil wire is pressed against the brazing material.

2. A method for manufacturing an antenna device according to claim 1, wherein the process is carried out at a timing in which a part of the melting process and a part of the removal process overlap.

3. The method for manufacturing an antenna device according to claim 1, wherein in the melting step, the brazing material is supplied to the surface of the pad portion with a thickness equal to or greater than the diameter of the coil wire.

4. A method for manufacturing an antenna device according to any one of claims 1 to 3, wherein in the removal step, the insulating film is decomposed and removed from the coil wire.

5. A method for manufacturing an antenna device according to any one of claims 1 to 3, wherein in the melting step, the temperature of at least one of the coil wire or the brazing material is measured, and the amount of laser irradiation is controlled so that the temperature is within a predetermined range higher than the melting point of the brazing material.

6. The method for manufacturing an antenna device according to claim 5, wherein the amount of laser irradiation is controlled so that the temperature is within a predetermined range higher than the decomposition temperature of the insulating film.

7. The method for manufacturing an antenna device according to claim 1, wherein in the wire arrangement step, the brazing material is formed on the surface of the pad portion in a mountain shape having a slope that slopes downward from the center to the periphery of the pad portion, and the coil wire is pressed against the slope of the brazing material.

8. The method for manufacturing an antenna device according to claim 7, wherein the coil wire is pressed against the slope toward the center of the pad portion.

9. A method for manufacturing an antenna device according to claim 1, comprising a cutting step in which, after the pad portion and the coil wire are joined with the brazing material, the coil wire and the base are cut, and a portion of the coil wire including one end and a portion of the base including the wire fixing portion are removed.

10. The base has a support portion against which the coil wire is pressed, causing the direction in which the coil wire is pulled out to change. In the wire arrangement step, the bent portion located between the portion and the end of the coil wire is pressed against the support portion of the base and bent. The method for manufacturing an antenna device according to claim 1, wherein one end of the coil wire that has been bent at the bent portion is wrapped around the wire fixing portion of the base.

11. The method for manufacturing an antenna device according to claim 1, wherein in the melting step, an inert gas is supplied to the brazing material in the direction in which the coil wire is pressurized.

Images