JP2006245160A - Ferrite ring core housing case - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a means for fixing a ring core for preventing spurious radiation to a structure, and a means for preventing a first electric wire in which a high frequency current that penetrates the ring core for preventing spurious radiation flows, and a second electric wire close to it from electromagnetically and static electrically coupling each other. <P>SOLUTION: An engaging hole is opened on a tab formed integrally with a ring core housing case for preventing spurious radiation, and a pawl formed on a chassis is engaged with the engaging hole, so that the ring core housing case for preventing spurious radiation is fixed to the chassis. A binding part for hooking the electric wire close to the ring core for preventing spurious radiation, so that the first electric wire is orthogonal to the second electric wire, is integrally formed with the ring core housing case for preventing spurious radiation. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  With regard to the storage case of the ferrite ring core for unnecessary radiation prevention, in which the cylindrical shaft center part is hollow and the electric wire is inserted into the hollow space, in detail, it is formed integrally with the ferrite ring core storage case for unnecessary radiation prevention By means of the mounting tab, the means for fixing the ferrite ring core for preventing unwanted radiation to the structure and the induction of unwanted radiation interference signal voltage to other wires arranged close to the wire through which high-frequency current flows are prevented. The present invention relates to a ferrite ring core storage case for preventing unwanted radiation formed integrally with the ferrite ring core housing case for preventing unwanted radiation.

  Recently, as the circuit configuration of electronic devices has shifted from the conventional analog circuit method to the digital circuit method, digital signal voltages and digital signal currents containing high-frequency components of higher harmonics handled in digital circuits have become electronic. Radiation as electromagnetic interference noise from circuit parts and wiring has become a problem, and the upper limit of electromagnetic interference noise radiation is stipulated by laws and regulations and is strictly regulated. As seen in Patent Document 1, as a means for suppressing unnecessary radiant current including high-frequency components flowing through an electric wire, the periphery of the electric wire through which the high-frequency current flows is surrounded by a ferrite ring core obtained by sintering a metal oxide ferromagnetic material. The electromagnetic wave energy generated around the wire due to the high-frequency current flowing in the wire generates eddy currents in the ferrite ring core and converts the high-frequency energy into heat loss (eddy current loss), thereby radiating electromagnetic interference signals. Means for reducing are widely applied.

As described above, since the ferrite ring core for suppressing unnecessary radiation from the electric wire through which the high-frequency current flows is formed by firing the metal oxide powder, the electronic circuit component of about several tens of grams has a relatively large mass. Since large mass parts are installed in the middle of flexible and unstable electric wires, the ferrite ring core is attached to the surrounding electronic parts due to vibrations and shocks during transportation of the electronic device product incorporating the ferrite core ring. Contact and damage could occur and the ferrite ring core had to be secured to a rigid structure. Further, since a ferrite ring core having a large mass is attached in the middle of the first electric wire, the passage position of the electric wire fluctuates, approaches the second electric wire in the device, and electromagnetically and electrostatically with the second electric wire. And the current and voltage that cause unnecessary radiation interference are induced in the second electric wire.

Hereinafter, a ferrite ring core for preventing unwanted radiation according to the prior art will be described with reference to FIGS. FIG. 3A is an external perspective view of the unnecessary radiation preventing ferrite ring core 11, and a cylindrical ferrite ring core is accommodated in the cylindrical resin case 15. The ferrite ring core has a hollow shaft center portion, and electric wire insertion holes 12 are formed on both side surfaces of the resin case 15. FIG. 3B is a perspective view showing a state in which the first electric wire 9 is inserted through the electric wire insertion hole 12 penetrating the central axis of the unnecessary radiation preventing ferrite ring core 11.

FIG. 4 is an exploded perspective view of the ferrite ring core for preventing unwanted radiation. The resin case 15 in FIG. 4 is formed in a cylindrical shape. The resin case 15 has electric wire insertion holes 12 on both side surfaces, and is divided into two case shells on the surface including the central axis. Both the upper shell 15a and the lower shell 15b which are divided equally share one straight side to form a hinge portion 15c. Each of the other straight sides of the case shell facing the hinge portion 15c forms an opening and serves as an opening for inserting the ferrite ring core 13 into the resin case 15 constituted by both divided shells.
JP 2000-173827 A

  A ferrite ring core for suppressing unnecessary radiation from an electric wire through which a high-frequency current flows is formed by firing metal oxide powder and has a large mass. Because large mass components are installed in the middle of flexible and unstable electric wires, the ferrite ring core contacts the surrounding electronic components due to vibration or impact during transportation of the electronic product incorporating the ferrite ring core. However, the surrounding electronic components may be damaged, and it is necessary to fix the ferrite ring core to a rigid structure.

In addition, the second electric wire arranged close to the first electric wire on which the ferrite ring core is mounted moves in an unstable manner, approaches the first electric wire, and electromagnetically and electrostatically with the second electric wire. In order to avoid the problem of inducing current or voltage that causes unnecessary radiation interference to the second wire by coupling, the outer frame of the ferrite ring core, which has been large in mass, has been attached to the nearby chassis frame with adhesive tape or a binding member. , Brackets, or fixed structures such as printed wiring boards.

  In order to prevent radiation of unwanted radiation interference signals from the electric wire due to the high-frequency current flowing through the electric wire of the electronic device, a tab attached to the storage case of the ferrite ring core through which the electric wire is inserted is formed by a fixing means formed integrally with the storage case. Secure to a structure such as a chassis.

Forming an electric wire binding portion for fixing the second electric wire in the ferrite core storage case through which the first electric wire in the electronic device is inserted, and making the first electric wire and the second electric wire orthogonal without translation The binding portion of the second electric wire is formed integrally with the ferrite core storage case.

For the purpose of preventing unwanted radiation interference, by fixing a large mass ferrite ring core attached to the middle of a flexible and unstable wire to a structure such as a chassis, during transportation of electronic equipment incorporating the ferrite ring core It is possible to prevent the ferrite ring core from coming into contact with and damaging the surrounding electronic components due to the vibration and impact of the.

The first electric wire inserted into the ferrite ring core and the second electric wire in the electronic device are integrated with the outer surface of the storage case of the ferrite core so that the second electric wire is orthogonal to each other without translation. By forming and bundling the second electric wire by the bundling portion, the second electric wire approaches the first electric wire in the vicinity and induces a current or voltage that causes unnecessary radiation interference in the second electric wire. Thus, it is possible to prevent the second electric wire from being a new source of unwanted radiation interference signals.

  FIG. 1 shows a first embodiment according to the present invention. In the external perspective view of the ring core 1 for preventing unwanted radiation with a fixing device shown in FIG. 1 (a), there are wires on both sides of the resin case 2 formed in a cylindrical shape, as in the prior art. An insertion hole 4 is provided, and the upper shell 2 a and the lower shell 2 b are formed equally on the plane including the central axis, and the ferrite ring core is accommodated inside the resin case 2. Both case shells divided into equal parts share one straight side to form a hinge portion 2c, and the other straight side of the case shell opposite to the hinge portion 2c is engaged by the upper and lower shell locking portions 2d. Are combined.

FIG. 1B shows the first side surface of the resin case 2. An attachment tab 3 is formed below the periphery of the opening of the lower shell 2b, and the attachment tab 3 is provided with a first chassis claw fitting hole 3a. FIG. 1C shows the second side surface of the resin case 2. A second chassis claw fitting hole 3b is formed on the lower side around the opening of the lower shell 2b.

FIG.1 (d) is a top view of the chassis 5 which attaches the ring core 1 for unnecessary radiation prevention with a fixing device which is the 1st Example of this invention. The chassis 5 has a ring core mounting hole with a long side dimension slightly longer than the axial length of the cylindrical ring 1 for unnecessary radiation prevention with the fixing device and a short side dimension shorter than the diameter of the unnecessary radiation prevention ring core 1 with the fixing device. 5a is drilled. A protruding first chassis claw 5b and a second chassis claw 5c are disposed at the center of both short sides of the ring core mounting hole 5a.

FIG. 1E is a longitudinal sectional view showing a process of fixing the unnecessary radiation preventing ring core 1 with the fixing device shown in FIG. The resin case 2 of the unnecessary radiation preventing ring core 1 with the fixing device is fitted into the ring core mounting hole 5a formed in the chassis 5, and the second case side surface of the resin case 2 of the unnecessary radiation preventing ring core 1 with the fixing device is fitted. The protruding second chassis claw 5c provided in the chassis 5 is fitted into the second chassis claw fitting hole 3b formed in 2f.

Next, when the resin case 2 is pushed in the direction of the arrow “A” shown in FIG. 1 (e), the resin case 2 is slightly outward from the periphery of the opening of the first side surface 2 e of the resin case 2. The mounting tab 3 provided so as to protrude into the resin case 2 is pushed inward of the resin case 2. Further, when the resin case 2 is pushed in the direction of the arrow “A” shown in FIG. 1 (e), the first chassis claw fitting hole 3 a formed in the mounting tab 3 projects from the chassis 5. 1, and the urging attachment tab 3 is restored to the outside of the resin case 2, and the unnecessary radiation preventing ring core 1 with a fixing device is firmly fixed to the chassis 5. .

Next, a second embodiment of the present invention will be described with reference to FIG. In FIG. 2, reference numeral 6 denotes an unnecessary radiation preventing ring core with an electric wire binding device, and the first electric wire 9 is inserted into the electric wire insertion hole 8. The first electric wire 9 is connected to a digital circuit or a high-frequency circuit, and radiates an unnecessary electromagnetic interference signal around the first electric wire 9 by a high-frequency current. Therefore, the periphery of the first electric wire 9 in which the high-frequency current flows is surrounded by a ferrite ring core obtained by sintering a ferromagnetic metal oxide, and the first electric wire 9 is surrounded by the high-frequency current flowing in the first electric wire 9. The electromagnetic energy generated in the ferrite ring core is converted into eddy currents in the ferrite ring core, and high-frequency energy is consumed as heat loss, thereby reducing the radiation of electromagnetic interference signals.

Here, when the second electric wire 10 passes in the vicinity of the first electric wire 9 connected to the digital circuit or the high-frequency circuit, the shaft of the first electric wire 9 is caused by the high-frequency current flowing through the first electric wire 9. When a high frequency magnetic field is generated in the periphery and the second electric wire 10 passes through the high frequency magnetic field, a high frequency voltage having the same frequency as the high frequency current flowing through the first electric wire 9 is induced in the second electric wire 10, The 2nd electric wire 10 becomes a generation source of a new unnecessary radiation interference signal. In order to avoid this, it is necessary to avoid that the 1st electric wire 9 and the 2nd electric wire 10 in which a high frequency current flows approach and translate. For this reason, the second electric wire 10 which is not firmly held and the passage position is unstable moves to avoid translation with the first electric wire 9 through which a high-frequency current flows, and is shown in FIG. Thus, the second electric wire 9 and the first electric wire 9 are formed by forming the electric wire binding portion 7 integrally with the resin case 6 a on the outer surface of the resin case 6 a of the unnecessary radiation preventing ring core and binding the second electric wire 10. And also defines the crossover position.

As described above, the first electric wire 9 and the second electric wire 10 are formed by integrally forming the electric wire binding portion 7 on the outer surface of the resin case 6a of the unnecessary radiation preventing ring core 6 with the electric wire binding device. It becomes possible to make it orthogonal, and the induced voltage which generate | occur | produces in the 2nd electric wire 10 by the high frequency magnetic field produced around the high frequency current which flows into the 1st electric wire 9 can be kept to the minimum value.

Further, since the first electric wire 9 and the second electric wire 10 do not translate, the second electric wire 10 and the first electric wire 9 are connected to each other by electrostatic coupling between the two electric wires through the stray capacitance. It is possible to avoid induction of a high frequency voltage in the electric wire 10. Furthermore, since the ferrite ring core having a high magnetic permeability at a high frequency is interposed between both wires at the proximity point of the first electric wire 9 and the second electric wire 10, the ferrite ring core exhibits excellent high frequency shielding characteristics, It is possible to prevent a high frequency voltage from being induced in the second electric wire 10 by the high frequency current flowing in the first electric wire 9, and therefore the second electric wire 10 becomes a new unnecessary radiation interference signal interference generation source. This can be prevented.

  As an embodiment of the present invention, a means for fixing an unnecessary radiation preventing ferrite ring core component housed in a resin case to a chassis and a means for defining a passage position of an electric wire adjacent to the unnecessary radiation preventing ferrite ring core will be described. However, the present invention is not limited to this, and when a small electronic component having a metal exterior is fixed to a printed wiring board or the like, or electromagnetic coupling between a transformer that leaks magnetic flux and an electric wire that passes close to the transformer For the purpose of prevention, it is equally suitable to apply the present invention.

FIG. 1A is an external perspective view, FIGS. 1B and 1C are left and right side views, and FIG. 1D of the ring core for preventing unwanted radiation with a fixing device according to the first embodiment of the present invention. Is a plan view of the mounting chassis, and FIG. 1E is a longitudinal sectional view. It is an external appearance perspective view which shows the usage example of the ring core for unnecessary radiation prevention with an electric wire binding apparatus which concerns on 2nd Example of this invention. FIG. 3A is an external perspective view and FIG. 3B is an external perspective view showing an example of use of a conventional ring core for preventing unwanted radiation. It is a disassembled perspective view of the ring core for unnecessary radiation prevention by a prior art.

Explanation of symbols

1: Ring core 2 for preventing unnecessary radiation with a fixing device 2: Resin case 2a: Upper shell 2b: Lower shell 2c: Hinge portion 2d: Upper and lower shell locking portions 2e: Side surface of first case 2f: Side surface of second case 3: Installation Tab 3a: first chassis claw fitting hole 3b: second chassis claw fitting hole 4: electric wire insertion hole 5: chassis 5a: ring core mounting hole 5b: first chassis claw 5c: second chassis claw 5d : Reinforced bending part 6: Unnecessary radiation preventing ring core with wire bundling device 6a: Resin case 7: Electric wire bundling part 8: Wire insertion hole 9: First electric wire 10: Second electric wire 11: Ferrite ring core 12 for preventing unnecessary radiation : Electric wire insertion hole 13: Ferrite ring core 14: Ferrite ring core electric wire insertion hole 15: Resin case 15a: Upper shell 15b: Lower shell 15c : Hinge

Claims (3)

  In order to insert an electric wire in an electronic device, it is characterized by comprising a ferrite ring core having a hollow cylindrical shaft center and a means for fixing the storage case of the ferrite ring core to a structure such as a chassis. Ferrite ring core storage case.   A ferrite comprising a device for fixing the second electric wire to the outer surface of the ferrite ring core storage case in which a cylindrical shaft center portion is formed in a hollow shape so as to insert the first electric wire in the electronic device Ring core storage case.   The ferrite ring core storage case according to claim 2, wherein the ferrite ring core storage case is fixed by a first electric wire that passes through the axial center portion of the cylindrical ferrite ring core storage case, and an electric wire fixing device provided on an outer surface of the ferrite ring core storage case. A ferrite ring core storage case, wherein the electric wire fixing device is formed so that the second electric wires are orthogonal to each other.

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