JP2010081088A - Antenna for transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve working efficiency while preventing or suppressing base melting at the time of bonding a capacitor and an electrode terminal. <P>SOLUTION: The antenna is provided with a bobbin 13 formed in a cylindrical shape, a magnetic core 3 to be inserted into a cylinder hole of the bobbin 13, a coil 4 wound around the bobbin 13, and a base 6 formed integrally with the bobbin 13. Moreover, the electrode terminal 8 is placed on the base 6. The electrode terminal 8 has junctions 23, 24 projected from the base 6. Moreover, the capacitor 11 is joined to the junctions 23, 24 of the electrode terminal 8. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a transmission antenna including a magnetic core, a coil, and a capacitor, and more particularly to a transmission antenna that transmits a signal.

  In recent years, for example, a keyless entry system that can be locked and unlocked without directly touching a door of an automobile or a house by transmitting and receiving signal radio waves has been put into practical use.

  A conventional transmitting antenna constitutes a resonance circuit by a magnetic core, a coil wound around the magnetic core, and a capacitor connected in series to the coil. When an AC voltage is applied to the transmitting antenna in the peripheral band of the resonance frequency obtained from this resonance circuit, a magnetic field is generated, and the generated magnetic field can be propagated into the atmosphere. Then, when a user having a remote control device with a built-in transmission antenna enters or exits the magnetic field propagation range generated by the transmission antenna, the remote control device operates, and the vehicle or house The doors such as can be locked or unlocked.

  As this type of conventional transmitting antenna, for example, there is one described in Patent Document 1. Patent Document 1 discloses a transmitting antenna composed of an antenna coil having a core around which a winding is wound, and a capacitor that is connected to the winding and forms a series resonance circuit with the antenna coil. There is a description about. A chip capacitor is used as the capacitor of the transmitting antenna described in Patent Document 1.

JP 2007-288345 A

  However, the transmitting antenna described in Patent Document 1 uses a chip capacitor as a capacitor. In order to mount the chip capacitor on the base of the transmitting antenna, a series of steps is required in which cream solder is applied to the mounting portion, the chip capacitor is mounted, and the reflow furnace is passed. And since the reflow furnace apparatus is difficult to add to the automatic production line of the transmitting antenna, it was installed in a place different from the production line in the factory. For this reason, the transmitting antenna described in Patent Document 1 has a problem that it takes a lot of time and manpower to realize the above production process.

  Furthermore, a plastic material is used for the base of the transmitting antenna. This plastic material cannot withstand the hot air of the reflow furnace and has a problem of thermal deterioration. In order to solve this problem, a resin material having high heat resistance is generally used as a base material. However, a material having high heat resistance has a problem that the cost is high, and even if a material having high heat resistance is used, the periphery of the capacitor mounting portion is somewhat deteriorated.

  Further, it is conceivable to use a lead type capacitor instead of the chip capacitor. However, in order to join the lead type capacitor to the electrode terminal without melting the base, it is necessary to accurately maintain the mounting position of the capacitor, and high mounting accuracy is required. For this reason, there is a problem that it is very difficult to assemble the transmitting antenna.

  In view of the above problems, an object of the present invention is to provide a transmitting antenna capable of preventing or suppressing melting of a base when a capacitor and an electrode terminal are joined and improving work efficiency. is there.

  In order to solve the above problems and achieve the object of the present invention, a bobbin formed in a cylindrical shape, a magnetic core inserted into a cylindrical hole of the bobbin, a coil wound around the bobbin, and a bobbin are integrated. And a base formed thereon. Furthermore, the electrode terminal which has the junction part which protrudes from a base, and the capacitor | condenser joined to the junction part of this electrode terminal were provided.

  According to the transmitting antenna of the present invention, since the joint portion of the electrode terminal connected to the capacitor protrudes from the base, heat generated when joining the capacitor and the joint portion is prevented from being transmitted to the base, or Can be suppressed. As a result, it is possible to prevent or suppress the base from being melted by heat generated when the capacitor and the joint are joined, and to improve the yield. Further, since the joining position of the capacitor and the electrode terminal is located outside the base, joining means other than soldering can be used, and the work efficiency of assembling the transmitting antenna can be improved.

  Hereinafter, embodiments of the transmitting antenna of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected to the common member in each figure. The present invention is not limited to the following form.

1. First Embodiment [Configuration of Transmitting Antenna]
First, a transmitting antenna according to a first embodiment of the present invention (hereinafter referred to as “this example”) will be described with reference to FIGS. 1 is a perspective view showing the transmitting antenna of this example, FIG. 2 is a perspective view showing a state where the case is removed from the transmitting antenna of this example, and FIG. 3 is a perspective view of the transmitting antenna of this example as seen from the bobbin side. FIG. FIG. 4 is a front view of the transmitting antenna of this example, and FIG. 5 is a front view showing a base and electrode terminals according to the transmitting antenna of this example. FIG. 5 is an explanatory view showing a state in which the electrode terminal and the base are integrally formed, and FIG. 7 is a side view showing a state in which a capacitor is joined to the electrode terminal.

  As shown in FIGS. 1 to 4, the transmitting antenna 1 includes a case 2, a magnetic core 3 housed in the case 2, a coil 4 wound around the magnetic core, a base 6, It is composed of three electrode terminals 7, 8, 9 formed integrally with the base 6. Further, the transmitting antenna 1 has a capacitor 11 with a leg joined to the first electrode terminal 7 and the second electrode terminal 8.

[Case]
The case 2 is formed in a hollow, substantially rectangular parallelepiped shape. The case 2 has an opening 2a having one end in the axial direction opened on the entire surface, and the other end in the axial direction is closed. The case 2 is provided with an engagement receiving portion 2 b for engaging with the base 6. In addition, although the example in which the case 2 is formed in a rectangular parallelepiped shape has been described, the shape of the case 2 may be formed in a columnar shape.

  Case 2 is made of ABS (Acrylonitrile Butadiene Styrene), PBT (Poly Buthylene Terephthalete), PPS (Poly Phenylene), which is excellent in mechanical strength, chemical resistance, heat resistance and moisture resistance. Sulfide (poly-phenylene-sulfide) resin or a mixture thereof. In addition to the above, the case 2 may be formed using a resin such as POM (polyacetal) or PPE (polyphenylene ether).

[Magnetic core]
The magnetic core 3 is formed in a substantially rectangular parallelepiped shape. Examples of the material of the magnetic core 3 include Mn—Zn ferrite so that a strong magnetic field can be excited. The material of the magnetic core 3 is not limited to Mn—Zn ferrite, and other magnetic materials such as Ni—Zn ferrite having a desired magnetic characteristic, metal magnetic materials, and the like can be applied. . Furthermore, although the example which formed the magnetic body core 3 in the rectangular parallelepiped shape was demonstrated in this example, you may form the shape of the magnetic body core 3 in a column shape. And the magnetic body core 3 is inserted in the cylinder hole of the bobbin 13 formed integrally with the base 6 mentioned later. Further, the coil 4 is wound around the bobbin 13 in which the magnetic core 3 is inserted in the axial direction.

[Capacitor]
The capacitor 11 used in this example is composed of a main body 11a and two legs 11b and 11b which are connection terminals. The two leg portions 11b and 11b protrude with a predetermined interval from one side of the main body portion 11a. The capacitor 11 is mounted on the base 6.

[base]
As shown in FIGS. 2, 3, 4 and 5B, the base 6 has a substantially rectangular parallelepiped shape having two concave portions recessed in a substantially square shape. The base 6 has a bobbin 13 into which the magnetic core 3 is inserted on one end side in the axial direction, and an exposed end portion 14 having a rectangular tube shape on the other end side in the axial direction. The bobbin 13 is formed in a rectangular tube shape, and the coil 4 is wound around it. And as for this bobbin 13, the magnetic body core 3 is inserted in the cylinder hole. The exposed end portion 14 is exposed to the outside from the opening 2 a of the case 2 when the base 6 is stored in the case 2. The shape of the bobbin 13 is preferably formed so as to correspond to the shape of the magnetic core 3. The bobbin 13 may be formed in a cylindrical shape.

  Further, the base 6 is provided with two concave portions 15 and 16 and a flange portion 17 on the side surface portion. The first concave portion 15 is located on one side of the side surface portion of the base 6, and the second concave portion 16 is on the other side of the side surface portion of the base 6 that is opposite to the first concave portion 15 in the base 6. Is provided. The first recess 15 and the second recess 16 are recessed in a substantially square shape from the side surface of the base 6 toward the inside.

  The flange portion 17 is located on the exposed end portion 14 side of the first concave portion 15 and the second concave portion 16. The flange portion 17 protrudes from the side surface portion of the base 6 substantially perpendicularly. Further, the flange portion 17 is formed with an engaging portion 18 that engages with an engaging receiving portion 2 b provided in the case 2. The engaging portion 18 is a protrusion having a substantially triangular cross section.

  Further, as shown in FIGS. 3 and 5B, a mounting portion 28 and a guide groove 29 are provided on the upper surface portion of the base 6. The mounting portion 28 is a concave portion that is recessed from the upper surface portion of the base 6 in a substantially square shape. Note that the shape of the mounting portion 28 is not limited to a substantially square shape, but may be a substantially circular recess. That is, the shape of the mounting portion 28 is set according to the shape of the main body portion 11 a of the capacitor 41. And the main-body part 11a of the capacitor | condenser 41 is mounted and fitted in this mounting part 28. FIG.

  The guide grooves 29 are two grooves formed from the placement portion 28 to the second recess 16. Then, the two legs 11 b and 11 b of the capacitor 41 are fitted into the guide groove 29. Accordingly, the two leg portions 11 b and 11 b protrude outward from the side surface of the second recess 16 of the base 6, and are guided on the first joint portion 23 and the second joint portion 24. As a result, the capacitor 11 can be mounted on the base 6 very easily by fitting the two leg portions 11b and 11b of the capacitor 11 into the guide groove 29 and mounting the main body portion 11a on the mounting portion 28. In this example, the number of guide grooves 29 is two. However, the present invention is not limited to this, and the object can be achieved by integrating two guide grooves 29 into one. .

  Further, the base 6 is provided with a guide portion 19. The guide portion 19 is composed of a protrusion and a recess disposed on the upper surface portion of the base 6. One terminal portion 4a and the other terminal portion 4b of the coil 4 extend along the corners of the guide portion 19. Thereby, the guide part 19 is guiding the two terminal parts 4a and 4b of the coil 4 to the 1st binding terminal piece and the 2nd binding terminal piece which are mentioned later. And the base 6 which has such a structure is formed with nonelectroconductive and nonmagnetic resin. Further, as shown in FIGS. 5 and 6, the base 6 and the three electrode terminals 7, 8, 9 are integrally formed by, for example, insert molding.

[Electrode terminal]
As shown in FIG. 5A, the first electrode terminal 7 has a flat plate shape. It has the 1st terminal piece 21 to which one terminal part 4a of the coil 4 is bound and fixed, and the 1st junction part 23 to which the capacitor | condenser 11 is joined. The second electrode terminal 8 has a substantially L-shaped flat plate shape. The second electrode terminal 8 has a second joint portion 24 to which the capacitor 11 is joined at one end portion, and a first electrode 26 at the other end portion. The third electrode terminal 9 has a substantially L-shaped plate shape. The third electrode terminal 9 has a second terminal piece 22 to which the other terminal portion 4 b of the coil 4 is bound and fixed at one end, and a second electrode 27.

  As shown in FIGS. 2, 3 and 6, when the first terminal piece 21 of the first electrode terminal 7 and the second terminal piece 22 of the third electrode terminal 9 are formed integrally with the base 6. Further, the base 6 protrudes from the first recess 15 of the base 6 to the outside substantially perpendicular to the side surface of the base 6. When the first electrode 26 of the second electrode terminal 8 and the second electrode 27 of the third electrode terminal 9 are formed integrally with the base 6, they are disposed in the cylindrical hole of the exposed end portion 14 of the base 6. Is done.

  When the first joint 23 of the first electrode terminal 7 and the second joint 24 of the second electrode terminal 8 are formed integrally with the base 6, the second joint 16 of the base 6 extends outward from the second recess 16. It projects substantially perpendicularly to the side surface of the base 6. Moreover, as shown in FIG. 6, the 1st junction part 23 and the 2nd junction part 24 are arrange | positioned at predetermined intervals.

  The first joint portion 23 is provided with a tongue piece 23a, and similarly, the second joint portion 24 is provided with a tongue piece 24a. As shown in FIG. 7, the tongue piece 23 a is bent so as to face the joint surface 23 b of the first joint portion 23. Further, one leg portion 11 b of the capacitor 11 is interposed between the tongue piece 23 a and the joint surface 23 b of the first joint portion 23. Similarly, the tongue piece 24 a is bent so as to face the joint surface 24 b of the second joint portion 24. Further, the other leg portion 11b of the capacitor 11 is interposed between the tongue piece 24a and the joint surface 24b of the second joint portion.

  The two legs 11b and 11b of the capacitor 11 are interposed between the tongue pieces 23a and 24a of the first and second joints 23 and 24 and the joint surfaces 23b and 23b. 2 joints 23 and 23 are joined.

  Further, as shown in FIG. 6, the protruding length from the first recess 15 in the first terminal piece 21 and the second terminal piece 22 is the length of the recess from the flange portion 17 in the first recess 15. It is set shorter than this. Similarly, the protruding length from the second recess 16 in the first joint 23 and the second joint 24 is set shorter than the length of the recess from the flange 17 in the second recess 16. Yes.

  This prevents the first and second terminal pieces 21 and 22 and the first and second joint portions 23 and 24 from protruding outward from the outermost shape of the base 6 indicated by a two-dot chain line in FIG. 6. Can do. As a result, when the base 6 is housed in the case 2, there is no possibility that the two electrode terminals 7 and 8 come into contact with the case 2. Moreover, it is possible to prevent the case 2 that houses the base 6 from becoming large, and it is possible to reduce the size of the transmitting antenna 1.

  As described above, in this example, a legged capacitor is used. Thus, for example, a joining method such as resistance welding or ultrasonic welding can be used without using a reflow furnace. As a result, the degree of freedom of the capacitor 11 joining operation can be improved, and the working efficiency can be improved. Further, it is only necessary to attach the capacitor 11 to the mounting portion 28 and the guide groove 29 and weld the joint portion. As a result, not only the number of processes is reduced, but also the time required for moving the workplace in the factory can be saved, so that the production efficiency can be increased.

[Assembling the transmitting antenna]
The transmitting antenna 1 of the present invention having such a configuration can be assembled as follows, for example. First, the three electrode terminals 7, 8, 9 and the bobbin 13 and the base 6 are integrally formed by insert molding, for example.

  As a result, the first terminal piece 21 of the first electrode terminal 7 and the second terminal piece 22 of the third electrode terminal 9 protrude from the first recess 15. In the second recess 16, the first joint 23 of the first electrode terminal 7 and the second joint 24 of the second electrode terminal 8 protrude. Further, the first electrode 26 of the second electrode terminal 8 and the second electrode 27 of the third electrode terminal 9 protrude from the cylindrical hole of the exposed end portion 14.

  Next, the magnetic other core 3 is inserted into the cylindrical hole of the bobbin 13 formed integrally with the base 6 and fixed by a fixing method such as an adhesive. Then, the coil 4 is wound in the axial direction of the bobbin 13. Note that the magnetic core 3 is not only fixed by an adhesive or the like, but the magnetic core 3 may be fitted into the cylindrical hole of the bobbin 13, for example.

  Next, the one terminal portion 4 a of the coil 4 is passed along the guide portion 19 of the base 6, and the one terminal portion 4 a is bound and fixed to the first terminal piece 21. Similarly, the other terminal portion 4 b of the coil 4 is passed along the guide portion 19 of the base 6, and the other terminal portion 4 b is fixed to the second terminal piece 22.

  Next, the main body portion 11 a of the capacitor 11 is placed and fitted into the placement portion 28 provided on the base 6. Further, the two leg portions 11 b and 11 b of the capacitor 11 are fitted into the two guide grooves 29 and 29. Therefore, the two legs 11 b and 11 b of the capacitor 11 are guided by the two guide grooves 29 and 29 and protrude outward from the side surface of the second recess 16 of the base 6. The two leg portions 11 b and 11 a are arranged on the joint surface 23 b of the first joint portion 23 and the joint surface 24 b of the second joint portion 24.

  Next, as shown in FIG. 7, the tongue piece 23a of the first joint portion 23 is bent so as to face the joint surface 23b. Then, the leg part 11b of the capacitor | condenser 11 is interposed between the tongue piece 23a in the 1st junction part 23, and the junction surface 23b. Next, for example, the leg 11b of the capacitor 11 and the first joint 23 are joined using a joining method such as resistance welding or ultrasonic welding.

  Similarly, as shown in FIG. 7, the tongue piece 24b of the second joint portion 24 is bent so as to face the joint surface 24b. Then, the leg part 11b of the capacitor | condenser 11 is interposed between the tongue piece 24a and the joint surface 23b in the 2nd junction part 24. FIG. Next, for example, the leg 11b of the capacitor 11 and the second joint 24 are joined using a joining method such as resistance welding or ultrasonic welding. Thereby, the 1st electrode terminal 7, the 2nd electrode terminal 8, and the capacitor | condenser 11 can be electrically connected.

  Moreover, the leg part 11b of the capacitor | condenser 11 is joined so that it may be pinched | interposed with a joining surface and a tongue piece. Thereby, even if the mounting position of the leg part 11b of the capacitor | condenser 11 shifts | deviates, the junction part 23 and 24 of the leg part 11b of the capacitor | condenser 11 and the 1st and 2nd electrode terminals 7 and 8 can be joined reliably. As a result, the dimensional accuracy required for the welding jig (welding machine) can be set low, and workability can be improved.

  Here, the first and second joint portions 23 and 24 are provided so as to protrude from the side surface portion of the base 6. Therefore, heat generated when the capacitor 11 is bonded to the first bonding portion 23 and the second bonding portion 24 can be prevented or suppressed from being transmitted to the base 6. In addition, the base 6 is provided with a mounting portion 28 and a guide groove 29 for mounting the main body portion 11a of the capacitor 11 and the two leg portions 11b and 11b. As a result, the capacitor 11 can be mounted on the base 6 very easily, and the assembly work can be facilitated.

  Furthermore, since the capacitor and the electrode terminal can be joined without using a reflow furnace, there is no possibility that the base is deteriorated by the hot air of the reflow furnace. Further, since no reflow furnace device is required, the production line can be simplified, and the working efficiency can be improved.

  Thereby, the coil assembly which consists of the magnetic body core 3, the coil 4, the base 6, and the capacitor | condenser 11 is completed.

  Next, the coil assembly is inserted into the opening 2 a of the case 2 from the other axial side of the magnetic core 3, and the coil assembly is housed in the case 2. Then, the engagement portion 18 of the base 6 is engaged with the engagement receiving portion 2 b of the case 2. Thereby, the assembly of the transmitting antenna 1 is completed. Of course, the method of assembling the transmitting antenna 1 is not limited to the above-described method, and it may be assembled by other procedures.

2. Second Embodiment Next, a transmission antenna according to a second embodiment of the present invention will be described with reference to FIG.
FIG. 8 is a side view of the base of the transmitting antenna according to the second embodiment.
As shown in FIG. 8, the transmitting antenna 1A according to the second embodiment is further provided with a second tongue piece at the joint portion of the transmitting antenna 1 according to the first embodiment. .

  The first joint portion 23A provided integrally with the base 6A has a first tongue piece 23aA and a second tongue piece 23cA. The first tongue piece 23aA is bent so as to face the joint surface 23bA of the first joint portion 23A. The second tongue piece 23cA is provided on the opposite side of the first tongue piece 23aA across the joint surface 23bA. The second tongue piece 23cA is bent so as to overlap the bent first tongue piece 23aA.

  Similarly, the second joint portion 24A has a first tongue piece 24aA and a second tongue piece 24cA. The first tongue piece 24aA is bent so as to face the joint surface 24bA of the second joint portion 24A. The second tongue piece 24cA is provided on the opposite side of the first tongue piece 24aA across the joint surface 24bA. The second tongue piece 24cA is bent so as to overlap with the bent first tongue piece 24aA.

  Other configurations are the same as those of the transmission antenna 1 according to the first embodiment described above, and thus description thereof is omitted. Also with the transmission antenna 1A having such a configuration, the same operations and effects as those of the transmission antenna 1 according to the first embodiment described above can be obtained.

  Note that according to the transmitting antenna 1A according to the second embodiment, the first tongue piece and the second tongue piece extending from both sides of the joint surface are provided in the joint portion. The first tongue piece and the second tongue piece guide the capacitor leg to the approximate center of the joint surface when the capacitor is placed. Thereby, the position of the leg part of a capacitor | condenser can be arrange | positioned to the approximate center of a joining surface easily and reliably. As a result, the workability can be further improved compared to the transmitting antenna 1 according to the first embodiment.

  The present invention is not limited to the embodiment described above and shown in the drawings, and various modifications can be made without departing from the scope of the invention described in the claims. For example, although the example which protrudes the 1st junction part and the 2nd junction part from the side of a base was explained, you may make the 1st and 2nd junction part project from the upper surface or back of a base.

1 is a perspective view showing a first embodiment of a transmitting antenna of the present invention. It is a perspective view which shows the state which removed the case from 1st Embodiment of the transmitting antenna of this invention. It is the perspective view which looked at the base which concerns on 1st Embodiment of the transmitting antenna of this invention from the bobbin side. It is a front view which shows 1st Embodiment of the antenna for transmission of this invention. The base and electrode terminal which concern on 1st Embodiment of the transmitting antenna of this invention are shown, FIG. 5A is an electrode terminal, FIG. 5B is a front view which shows a base. It is explanatory drawing which shows the state which formed integrally the electrode terminal and base which concern on 1st Embodiment of the antenna for transmission of this invention. It is a side view which shows the state which joined the capacitor | condenser to the electrode terminal which concerns on 1st Embodiment of the antenna for transmission of this invention. It is a side view which shows the state which joined the capacitor | condenser to the electrode terminal which concerns on 2nd Embodiment of the transmitting antenna of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,1A ... Transmitting antenna, 2 ... Case, 3 ... Magnetic body core, 4 ... Coil, 6, 6A ... Base, 7 ... 1st electrode terminal, 8 ... 2nd electrode terminal, 9 ... 3rd electrode Terminal 11, capacitor 13, bobbin 14, exposed end 15, first recess 16, 16 A, second recess 19, guide portion 23, first connection portion 24, second Connection part, 11a ... main body part, 11b ... leg part, 23a, 23aA, 24a, 24aA ... tongue piece (first tongue piece), 23b, 23bA, 24b, 24bA ... joint surface, 23cA, 24cA ... second tongue Piece 28 ... placement part 29 ... guide groove

Claims (3)

A bobbin formed in a cylindrical shape;
A magnetic core inserted in the bobbin tube hole;
A coil wound around the bobbin;
A base formed integrally with the bobbin;
An electrode terminal having a joint protruding from the base;
A capacitor joined to the joint of the electrode terminal;
Transmitting antenna equipped with. The transmitting antenna according to claim 1, wherein the base has a recess at a position where the joint protrudes. The base has a mounting portion on which the capacitor is mounted;
The transmission antenna according to claim 1, wherein the capacitor includes a main body portion that is placed on the placement portion and a leg portion that protrudes from the main body portion and is joined to the joint portion.

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