JP2003173914A - Choke coil with pot rivet type core - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a choke coil with pot rivet type core in which the lower end face of a columnar core is joined and fixed to the upper end face of a core pedestal in a facing state through a spacer. <P>SOLUTION: This choke coil is provided with a pot-type core 10 composed of a top wall 101 and a side wall 103 integrally constituted with the wall 101 and having a columnar core passing hole 105 at the central part of the top wall 101, a rivet type core 20 composed of a bottom plate 201 and the core pedestal 204' integrally erected on the plate 201, and a coil 3. This choke coil is also provided with the columnar core 6 and the spacer 7. The columnar core 6, and spacer 7, and core pedestal 204' are joined and fixed to each other in a state where the lower end face of the core 6 is faced to the upper end face of the pedestal 204' through the spacer 7, by joining and fixing the cores 10 and 20 to each other through the opened end face of the side wall 103 and the upper surface of the bottom plate 201. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pot rivet type core choke coil, and more particularly to precisely adjusting the gap between the core pedestal of the rivet type core and the pot type core to accurately adjust the inductance value of the choke coil. The present invention relates to a pot rivet type core choke coil for setting and assembling.

[0002]

2. Description of the Related Art A conventional example of the present invention will be described with reference to FIG. Reference numeral 10 denotes a pot type core made of ferrite.
Reference numeral 101 denotes a top wall of the square pot core 10. 103
Indicates a side wall of the pot core 10. Notches 104 are formed in the lower corners of the intersecting side walls 103 adjacent to each other. The pot-type core 10 is formed by filling ferrite fine powder in a mold and applying pressure. The pressure-molded body of the pot type core 10 made of this ferrite fine powder is then fired at a high temperature to form the ferrite pot type core 10.

Reference numeral 3 represents a coil. The coil 3 is formed by spirally winding an electric wire having a round or square cross section. Three
Reference numeral 1 denotes a coil terminal portion. The coil 3 is formed by spirally winding an electric wire and then applying an insulating material coating on the surface. The coil 3 is formed by winding the number of turns corresponding to the required inductance. 4 is a terminal. The terminal 4 includes a mounting portion 44 having a U-shaped cross section, and a coil connecting portion 4 integrally formed from the mounting portion 44.
5 and a locking projection 46 formed on the upper surface of the coil connecting portion 45.

Reference numeral 20 denotes a rivet core made of ferrite. The rivet-type core 20 includes a rectangular bottom plate 201 and a magnetic core portion 20 that is vertically provided integrally with the bottom plate 201 at the center thereof.
It consists of four. The height of the magnetic core portion 204 is designed to be lower than the height of the inner surface of the side wall 103 of the pot core 10, and the inner surface of the top wall 101 of the pot core and the magnetic core portion 20 of the rivet core 20 are designed.
A gap G of the magnetic path is formed between the end surface of No. 4 and the end surface of No. The gap G is adjusted to set the coil inductance. Reference numeral 202 denotes a thin fitting portion formed in an intermediate portion of two opposite sides of the bottom plate 201, and the mounting portion 44 having a U-shaped cross section of the terminal 4 is fitted and fixed. Reference numeral 203 denotes a terminal mounting surface, which is an area corresponding to the thickness of the terminal 4 and having a step lower than the surface of the bottom plate 201 by the thickness. As for the rivet core 20, the ferrite fine powder is filled in a mold and pressed to integrally form the magnetic core portion 204 and the bottom plate 201. The pressure-molded body of the rivet-type core made of this ferrite fine powder is then fired at a high temperature to obtain the rivet-type core 2
0 is configured.

The order of assembling the choke coil using the above components will be described. The pot type core 10, the coil 3, the terminal 4, and the rivet type core 20 are prepared. The terminal 4 is fitted and fixed to the terminal mounting surface 203 and the fitting thin portion 202 of the rivet core 20. The coil 3 is fitted to the magnetic core portion 204 of the rivet core 20. Next, the coil end portion 31 of the coil 3 is soldered to the coil connecting portion 45 of the terminal 4. At this time, the coil end portion 31 is temporarily fixed to the engaging protrusion 46 formed on the upper surface of the coil connecting portion 45 by a mess.

An epoxy-based synthetic resin adhesive is applied to the peripheral edge surface of the opening of the pot core 10 and the surface of the bottom plate 201 of the rivet core 20. Top wall 101 of pot core 10 and rivet core 2
In the state where the gap G is formed on the end surface of the magnetic core portion 204 of 0, the two are joined and fixed. The above completes the assembly of the choke coil. Here, the coil terminal portion 31 of the coil 3 is soldered to the coil connecting portion 45 of the terminal 4. That is, the coil connecting portion 4
The rivet-type core 20 having the coil 3 in which the coil terminal portion 31 is temporarily fixed to the locking projection 46 formed by projecting on the upper surface of the coil 5 is prepared, and the coil terminal portion 31 is temporarily fixed to the coil connecting portion 45. Is immersed in the molten solder in the solder bath.

[0007]

As described above, both the pot type core 10 and the rivet type core 20 are formed by filling the die with ferrite fine powder, pressurizing and molding, and firing at high temperature. Generally, it is difficult to say that the design accuracy of the processing including the pressurizing, molding and firing steps of this kind is high.
Finished pot type core 10 and rivet type core 2
Deforms to 0 and warps. This deformation or warpage is caused by the top wall 10 of the pot type core, which is directly related to the inductance value of the coil.
1 also affects the gap G between the inner surface and the end face of the magnetic core portion 204 of the rivet-type core, and cannot sufficiently secure the design accuracy of the inductance value.

The present invention adopts a construction in which the columnar core, the spacer and the core pedestal are joined and fixed to each other with the lower end face of the columnar core facing the upper end face of the core pedestal via the spacer 7. Accordingly, a pot rivet type core choke coil that solves the above problems is provided.

[0009]

A pot-shaped core 10 comprising a top wall 101 and a side wall 103 integrally formed with the top wall 101 is provided, and a columnar core is inserted in the center of the top wall 101. The holes 105 are formed, and the bottom plate 201 and the bottom plate 2 are formed.
01, a rivet-type core 20 composed of a core pedestal 204 ′ standing upright in the center, a coil 3 fitted and positioned on the core pedestal 204 ′, a columnar core 6 and a spacer 7 The pot type core 10 and the rivet type core 20 are joined and fixed to each other via the opening end face of the side wall 103 and the upper face of the bottom plate 201, and the lower end face of the columnar core 6 is placed on the core pedestal 204 ′ via the spacer 7. A pot rivet type core choke coil was constructed in which the columnar core 6, the spacer 7 and the core pedestal 204 ′ were joined and fixed to each other while facing the end faces.

A second aspect: In the pot rivet type core choke coil according to the first aspect, the height of the core pedestal 204 'is designed to be lower than the height of the side wall 103 of the pot type core 10. Formed core choke coil. Further, in the pot rivet type core choke coil according to any one of claims 3 and 4, the columnar core 6 has a sectional shape corresponding to the sectional shape of the columnar core insertion hole 105. A pot rivet-type core choke coil was designed in which the height was designed such that the sum of the height of the core pedestal 204 ′ and the thickness of the spacer 7 was substantially equal to the height of the side wall 103.

Further, claim 4: claim 1 to claim 3
In the pot rivet type core choke coil described in any of the above, the columnar core 6 is formed by selecting and using an appropriate material from ferromagnetic materials such as nickel alloy and manganese alloy. A core choke coil was constructed.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the examples of FIGS. FIG. 1 is an exploded perspective view of the embodiment, and FIG. 2 is a view for explaining an assembly order of the embodiment. Reference numeral 10 denotes a square pot core made of ferrite. Reference numeral 101 denotes a top wall of the pot type core 10.
Reference numeral 103 denotes a side wall of the pot type core 10. A notch 104 is formed in the lower corner of the intersecting side walls 103 adjacent to each other.
Are formed. Reference numeral 105 is a columnar core insertion hole formed in the central portion of the top wall 101.

The pot type core 10 is formed by filling a die with ferrite fine powder and pressing. The pressure-molded body of the pot type core 10 made of this ferrite fine powder is then fired at a high temperature to form the ferrite pot type core 10. Reference numeral 3 represents a coil. This coil 3 is formed by deforming a copper wire into a spiral shape. Reference numeral 31 indicates a coil terminal portion. The coil 3 is formed by spirally deforming a copper wire and then applying an insulating material coating on the surface.
The coil 3 is formed by winding the number of turns corresponding to the required inductance. And the coil 3 is
Generally, it is formed by winding a wire having a round or rectangular cross section.

Reference numeral 4 is a terminal. The terminal 4 includes a mounting portion 44 having a U-shaped cross section, a coil connecting portion 45 integrally formed from the mounting portion 44, and a locking protrusion 46 formed on the upper surface of the coil connecting portion 45. Reference numeral 20 denotes a rivet core made of ferrite. Rivet core 2
Reference numeral 0 is composed of a rectangular bottom plate 201 and a core pedestal 204 ′ which is integrally formed with the bottom plate 201 and stands upright at the center thereof. The height of the core pedestal 204 ′ is designed to be lower than the height of the side wall 103 of the pot type core 10. Reference numeral 202 denotes a thin fitting portion formed in an intermediate portion of two opposite sides of the bottom plate 201, and the mounting portion 44 having a U-shaped cross section of the terminal 4 is fitted and fixed.
203 is a terminal mounting surface, which corresponds to the plate thickness of the terminal 4,
This is a region that is stepped lower than the surface of the bottom plate 201 by this thickness.

Also in the rivet type core 20, ferrite fine powder is filled in a die and pressed to integrally form the core pedestal 204 'and the bottom plate 201. The rivet core pressure-molded body made of this ferrite fine powder is then fired at a high temperature to form the rivet core 20. 6 is a columnar core. The cross-sectional shape of the columnar core 6 is the pot type core 1.
It is designed corresponding to the cross-sectional shape of the columnar core insertion hole 105 formed in the top wall 101 of No. 0. The height of the columnar core 6 is the same as the height of the core pedestal 204 ′ of the rivet type core 20,
The sum of the thickness of the spacer 7 to be described next is designed to be substantially equal to the height of the side wall 103 of the pot type core 10. The columnar core 6 is made of a ferromagnetic material such as nickel alloy and manganese alloy.

Reference numeral 7 is a spacer. The spacer 7 is made of a non-magnetic material such as synthetic resin. The order of assembling the choke coil using the above components will be described. First, the columnar core 6, the spacer 7, the pot type core 10, the coil 3, the terminal 4, and the rivet type core 20 are prepared. The terminal 4 is fitted and fixed to the terminal mounting surface 203 and the fitting thin portion 202 of the rivet core 20.

Core pedestal 20 of rivet core 20
The coil 3 is fitted to 4 '. Next, the coil end portion 31 of the coil 3 is soldered to the coil connecting portion 45 of the terminal 4. At this time, the coil end portion 31 is temporarily fixed to the engaging protrusion 46 formed on the upper surface of the coil connecting portion 45 by a mess. The peripheral edge surface of the opening of the pot type core 10 and the rivet type core 2
An epoxy synthetic resin adhesive is applied to the surface of the bottom plate 201 of No. 0 to bond and fix the two. The spacer 7 is inserted into the pot type core 10 through the columnar core insertion hole 105 formed at the center of the top wall 101, and placed on the upper end surface of the core pedestal 204 ′ of the rivet type core 20. At this time, an adhesive is applied to the entire surface of the spacer 7.

Next, the columnar core 6 is inserted into the pot type core 10 through the columnar core insertion hole 105, and is placed and pressed onto the spacer 7. Here, with the lower end surface of the columnar core 6 facing the upper end surface of the core pedestal 204 ′ with the spacer 7 in between, the columnar core 6, the spacer 7, and the core pedestal 20 are provided.
The 3'of 4'are joined and fixed to each other. Then, the sum of the height of the columnar core 6, the height of the core pedestal 204 ′ of the rivet type core 20 and the thickness of the spacer 7 is defined as the side wall 1 of the pot type core 10.
03, the upper end of the columnar core 6 is designed to be approximately equal to the height of the columnar core insertion hole 105 of the pot type core 10.
Insert and fit into This completes the assembly of the pot rivet type core choke coil.

[0019]

As described above, according to the present invention, the magnetic path formed by the pot core 10 and the rivet core 20 is the bottom plate 201 of the rivet core 20.
It is formed via the core pedestal 204 ′, the spacer 7, the columnar core 6, the top wall 101, the side wall 103, and the bottom plate 201 of the pot core 10. In this pot rivet type core choke coil, the spacer 7 forms the gap G of the choke coil. That is, the thickness of the spacer 7 defines the gap G. Then, with the lower end surface of the columnar core 6 facing the upper end surface of the core pedestal 204 ′ with the spacer 7 interposed therebetween, the columnar core 6, the spacer 7, and the core pedestal 204 ′ are separated from each other.
Since they are fixed to each other by joining, the top wall 101 of the pot type core 10 and the bottom plate 201 of the rivet type core 20 are deformed and warped due to manufacturing, or even if the atmospheric state changes, the three types of mutual influences are increased. As long as the bonding and the spacer 7 are not damaged, the gap G defined by the thickness of the spacer 7
Does not occur, and variations in the inductance of the choke coil do not occur.

The inductance of the choke coil can be adjusted by changing the gap G. To adjust the change in the gap G, the thickness of the spacer 7 is changed and a corresponding change is made to the height of the columnar core 6. Therefore, it can be carried out precisely and easily. Furthermore, by selecting and using an appropriate material from among ferromagnetic materials such as nickel alloys and manganese alloys as the material for forming the columnar core 6, choke coils having various characteristics can be used, and the pot type core that is the main body of the choke coil can be used. It can be easily manufactured without modification of the rivet core 10 and the rivet core 20.

[Brief description of drawings]

FIG. 1 is an exploded perspective view illustrating an embodiment.

FIG. 2 is a diagram illustrating an assembly order of the embodiment.

FIG. 3 is a diagram illustrating a conventional example.

[Explanation of symbols]

10 pot type core 101 top wall 103 side wall 104 notch 105 columnar core insertion hole 20 rivet type core 201 bottom plate 201 202 fitting thin portion 203 terminal mounting surface 204 magnetic core portion 204 'core pedestal 3 coil 31 coil terminal portion 4 Terminal 44 Attachment Part 45 Coil Connection Part 46 Locking Protrusion 6 Columnar Core 7 Spacer G Gap

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) H01F 37/00 H01F 15/10 D

Claims (4)

[Claims] 1. A pot-shaped core comprising a top wall and a side wall integrally formed with the top wall, wherein a columnar core insertion hole is formed at the center of the top wall, and the bottom plate and the bottom plate are integrally formed at the center thereof. A rivet-type core consisting of a core pedestal standing upright, a coil fitted and positioned on the core pedestal, a columnar core, a spacer, and a pot-type core and a rivet-type core. Join and fix the columnar core, the spacer and the core pedestal with the bottom end of the columnar core facing the upper end of the core pedestal with the spacer fixed to each other. A pot rivet type core choke coil characterized in that 2. The pot rivet type core choke coil according to claim 1, wherein the height of the core pedestal is designed to be lower than the height of the side wall of the pot type core. coil. 3. The pot rivet type core choke coil according to claim 1, wherein the columnar core has a cross-sectional shape designed corresponding to the cross-sectional shape of the columnar core insertion hole. A pot rivet type core choke coil whose height is designed such that the sum of the height of the core pedestal and the thickness of the spacer is substantially equal to the height of the side wall. 4. The pot rivet type core choke coil according to claim 1, wherein the columnar core is made of a ferromagnetic material such as nickel alloy or manganese alloy. A pot rivet type core choke coil characterized by being constructed by using.