JP3568218B2 - Box noise filter - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a box-shaped noise filter for a large current.
[0002]
[Prior art]
A conventional noise filter for a large current is a box-shaped metal provided with an external connection terminal using an insulated bush and a choke coil having two or three windings in which a thick electric wire is manually wound around a toroidal core. The coil was housed in a container, the coil and the external connection terminal were connected by an insulated wire and a crimp terminal, and the embedding resin was poured into a metal container to a depth at which the lower portion of the coil was buried, and was solidified.
[0003]
[Problems to be solved by the invention]
The conventional box-shaped noise filter has the disadvantage that the handling of the embedded resin is troublesome, the time required for injection and solidification is long, and the choke coil, which is obtained by manually winding a thick electric wire, requires a lot of man-hours and finish. There were drawbacks that the size and shape varied greatly, the manufacturing cost was high, and the reliability of the electrical characteristics was poor. Further, the conventional box-shaped noise filter has a drawback that it is difficult to wire the insulated wire in the air, and that the assembling time is long.
[0004]
In order to eliminate the above-mentioned disadvantages of the prior art, in the box-shaped noise filter of the present invention, the choke coil is formed by bending the width direction of the rectangular electric wire into a curved shape so as to form two divided windings wound in the same winding direction in a cylindrical shape. A structure in which two or more eyeglass-shaped windings are connected to each other in a figure eight shape and a UU or UI core is combined, and the choke coil is fixed to the inner bottom of a box-shaped metal container via an insulating base. Further, by adopting a structure in which the connection conductor between the coil and the external connection terminal is fixed on the insulating base, the assembling work is easy, the automatic device can be easily applied, the working efficiency is good, and the cost is low. An object of the present invention is to provide a box-shaped noise filter having excellent characteristics and high reliability.
[0005]
[Means for Solving the Problems]
The present invention
Two or more split windings in the same winding direction in which a rectangular wire is wound into a cylindrical shape by bending the width direction into a curved shape, connecting two or more eyeglass-shaped windings and a split-type closed magnetic circuit core A choke coil combined via a partition plate, a box-shaped container in which an insulating terminal plate integrally penetrating an external connection terminal is fitted in a square notch provided on both short side walls, and an inner wall of the box-shaped container. A square step portion provided on a side surface to be fitted, into which a core presser fitting is fitted, and the partition plate provided parallel to the side surface at a central portion opposite to a plane contacting the inner bottom of the box-shaped container, are fitted. An insulating base having an elongated concave portion to be fitted and an arc-shaped concave portion provided between the elongated concave portions and mounting the bottom of the glasses-shaped winding, and the choke coil is housed in the box-shaped container. wherein a box-shaped noise filter formed of a fixed via the base to the inner bottom Te, the A box-shaped noise, wherein the holding metal is fixed to the base by abutting against an outer surface of a base of the core to hold the core in a closed magnetic circuit, and the choke coil is fixed to the base. Filter .
[0007]
The present invention is the above box-shaped noise filter, wherein the conductor connecting the choke coil and the external connection terminal is fixed on a base.
[0008]
[Action]
The insulating base is fixed to the inner bottom of the box-shaped metal container, and insulates and holds the choke coil and the connection conductor from the inner surface of the container. The core retainer is fixed to the insulating base to keep the core in a closed magnetic circuit and to hold the choke coil on the base. The connection conductor fixed to the base connects the coil and the external connection terminal at a fixed position.
[0009]
【Example】
FIG. 1 is an exploded perspective view showing one embodiment of the present invention in which a lid is omitted.
[0010]
In FIG. 1, a choke coil 1 (hereinafter, referred to as a coil) is a three-phase common mode choke coil, and is connected to an insulating base 3 (hereinafter, referred to as a base) disposed on the inner bottom of a box-shaped metal container 2. It is fixed using two U-shaped core press fittings 4 shown.
[0011]
The box-shaped metal container 2 is provided with a rectangular notch 5 on both short side walls of a rectangular opening, and an insulating terminal plate 6 in which three external connection terminals 7 are integrally formed is fitted into the notch 5 in the figure. It is.
[0012]
FIG. 3 shows the disassembled coil 1 together with the insulating base 3. The coil 1 is a combination of an eyeglass-shaped winding 8 and a UU-shaped core 9, and the first split winding 81 and the second split winding 82 of the eyeglass-shaped winding 8 are connected.
[0013]
As shown in FIG. 3, the eyeglass-shaped winding 8 is formed by vertically winding a rectangular electric wire having a rectangular cross section, in other words, bending the width direction of the electric wire into a curved shape and winding the rectangular electric wire into a cylindrical shape. A first split winding 81 (rightward in FIG. 3; winding direction is right-handed and left-handed) is formed, and the end of winding of the first split winding is the beginning of winding of the second split winding. And a second winding segment 82 is formed in the same winding direction as the first winding segment 81 (the left winding portion in FIG. 3 and the right winding portion goes to the right in FIG. 3). There is no problem even if the number of turns of the divided windings 81 and 82 is not the same. The eyeglass-shaped winding 8 can be made by an automatic device, and is wound in a single layer vertically, that is, in the width direction, so that the space factor is 70% as compared with the lap winding of a thick round wire having the same winding volume. From the stand to the 90% stand, stray capacitance decreases, dispersion of stray capacitance is small, coil frequency characteristics are good, and by dividing into glasses, magnetic coupling with the core is good. I have.
[0014]
In the UU-shaped core 9, both magnetic legs 91 have a hexagonal cross section, and a central portion of the base 92 has a circumferential surface. The cross-sectional shape of the magnetic leg may be circular, octagonal, or the like.
[0015]
The insulating base 3 is smaller than the inner bottom of the box-shaped metal container 2. And a rectangular thick plate having a size substantially in contact with both long side walls of the rectangular opening, and two recesses of a square step portion 32 provided on the upper surface and extending over the center of the inner wall contact side surface 31 of the box-shaped metal container 2. The portion has four elongated recesses 33 parallel to the inner wall contact side surface 31 and six arc recesses 34 connecting the elongated recesses 33, and the magnetic legs of the UU-shaped core 9 are mounted on the insulating cylinder 12, In order to set the choke coil 1 composed of the divided windings 81 and 82 of the plurality of eyeglass-shaped windings 8 fixed to the partition plate 11, the partition plate 11 is fitted into the elongated recess 33, and the eyeglass is inserted into the arc recess 34. The bottom of the shaped winding 8 is installed. Further, a connection conductor 10 having six U-grooves is fixed to the box-shaped metal container 2 so as to partially protrude outward along both sides facing the notch 5.
[0016]
To assemble the box-shaped noise filter, first, the choke coil 1 is assembled outside the box-shaped metal container 2. Between the four insulating partition plates 11 having two through holes corresponding to the central holes of the split windings 81 and 82 of the eyeglass-shaped winding 8, the three eyeglass-shaped windings 8 are sequentially sandwiched and concentrically. The insulating cylinder 12 is inserted into the communicating hole between the central hole and the through hole, and the magnetic legs 91 of the UU-shaped core 9 are inserted from both sides of the insulating cylinder 12 for temporary assembly. The temporary assembly is placed on the base 3, the partition plate 11 is fitted into the elongated recess 33, the bottom of the eyeglass-shaped winding 8 is inserted into the arc-shaped recess 34, and then the two core holding members 4 are connected to the square step 32. , And the upper free end of the core holding member 4 abuts against the outer surface of the base 92 of the UU-shaped core 9, and the core holding member 4 is screwed to the center wall surface of the square step 32. The choke coil 1 is fixed to the insulating base 3 by fixing the core holding member 4, and at the same time, the UU core 9 becomes a closed magnetic circuit.
Since both ends of the eyeglass-shaped winding 8 face the rising pieces on the insulating base 3 of the connection conductor 10, they can be easily connected by screwing and then soldering.
[0017]
The insulating base 3 integrated with the choke coil 1 is fitted into the box-shaped metal container 2 from which the insulating terminal plate 6 has been removed, and is positioned at the inner bottom and screwed. Since the eyeglass-shaped winding 8 and the connection conductor 10 are separated from the inner bottom of the box-shaped metal container 2, it is not necessary to cover the inner wall of the box-shaped metal container 2 with insulating paper.
[0018]
The insulating terminal plate 6 is fitted into the notch 5 of the box-shaped metal container 2. Since the screw rod inward of the external connection terminal 7 passes through the rising concave portion of the connection conductor 10, the external connection terminal 7 and the connection conductor 10 can be easily connected. By attaching a metal cover (not shown) to the box-shaped metal container 2, a box-shaped noise filter is completed.
[0019]
【The invention's effect】
As described above, according to the present invention, a rectangular metal wire made by an automatic device uses a vertically-wound eyeglass-shaped winding, the embedding resin is omitted, and the choke coil is connected to the box-shaped metal container via the insulating base. Since the structure is fixed to a single layer in the width direction, the space factor is increased from the 70% level to the 90% level as compared with a lap winding of a thick round wire having the same winding volume, and the floating capacity is increased. And the variation is reduced, the frequency characteristics of the coil are good, and the degree of magnetic coupling with the core is good. Further, the present invention provides a box-shaped noise filter for a large current which is easy to assemble, easy to apply an automatic device, can be manufactured efficiently, is inexpensive, has excellent characteristics and high reliability.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view showing an embodiment of the present invention without a lid.
2 is an exploded perspective view showing the choke coil shown in FIG. 1 together with an insulating base.
FIG. 3 is an external perspective view of a glasses-shaped winding used in the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Choke coil 2 Box-shaped metal container 3 Insulating base 4 Core holder 5 Notch 6 Insulating terminal plate 7 External connection terminal 8 Glass-shaped winding 9 UU-shaped core 10 Connection conductor 11 Partition plate 12 Insulating cylinder 31 Inner wall contact side 32 Square step 33 Slender concave part 34 Arc concave part 81, 82 Split winding 91 Magnetic leg 92 Base

Claims (2)

The width direction is bent into a curved shape, and two or more split windings in the same winding direction, in which a rectangular electric wire is wound in a cylindrical shape, are connected in an eight-shape, and at least two of the eyeglass-shaped windings and a split-type closed magnetic circuit core. A box-shaped container in which an insulated terminal plate integrally penetrating an external connection terminal is fitted in a square notch provided on both short side walls, and an inner wall of the box-shaped container. The partition plate, which is provided on a side surface that comes into contact with, and is provided in parallel with the side surface at a central portion opposite to a plane that is in contact with an inner bottom of the box-shaped container, and a square step portion into which a core holding member is fitted. An insulating base having an elongated concave portion to be fitted therein and an arcuate concave portion provided between the elongated concave portions for placing a bottom portion of the eyeglass-shaped winding; and storing the choke coil in the box-shaped container. a box-shaped noise filter fixed through the base in said bottom and said co Box-shaped noise filter of the core by a bracing contact with the outer surface of the base of the core is fixed to the base and holds the closed magnetic circuit, characterized in that fixed to the choke coil to the base . The box-shaped noise filter according to claim 1 , wherein a conductor connecting the choke coil and the external connection terminal is fixed on the base.

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