JP2005150561A - Noise absorber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noise absorber having a snap fit structure in which a cable is difficult to slip out of a core case even an external force is applied. <P>SOLUTION: The noise absorber comprises a pair of core strips 2a, 2b that are divided into two from a cylindrical magnetic core 2 in an axis direction, and a core case 3 which houses these core strips 2a, 2b with a pair of case strips 3a, 3b divided into two in an axis direction connected by a hinge 7. A locking hook is provided at one side of the case strip 3a opposed to the other side to which the hinge is provided, and a locking nail for engaging with the locking hook is provided to the case strip 3b. Steps 4a, 5a are formed at the respective engaging parts of the locking hook 4 and the locking nail 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a noise absorbing device for preventing radiation noise from a cable such as a signal line connected to an electronic device or induction noise to the cable.

  As digital signals are digitized and speeded up in electronic devices, it has been an important problem to deal with signal interference and malfunction due to unnecessary radiation noise generated and received on signal lines.

  As a countermeasure for this, there is a noise absorbing device in which a split magnetic core such as Ni-Zn ferrite is passed through a cable between electronic devices, and the magnetic core is housed inside the split core case. Used (for example, Patent Document 1, Patent Document 2, etc.). When using such a noise absorbing device, it is necessary to hold the magnetic core in the core case and to attach it stably to the cable, so various structures are employed. For example, Patent Document 1 discloses that an elastic piece is interposed in a magnetic core and accommodated in the bottom portion of the core case to prevent the magnetic core from falling off the core case. Patent Document 2 discloses that a protrusion is provided on the inner side wall of the core case, and a concave portion that engages with the protrusion is provided in the magnetic core to prevent the magnetic core from falling off the core case.

  FIG. 3 shows a typical conventional noise absorber. As shown in FIGS. 3A and 3B, a conventional noise absorber 11 includes a pair of core pieces 2a and 2b obtained by dividing a cylindrical magnetic core into two in the axial direction, and these core pieces. It consists of a core case 13 in which a pair of case pieces 13 a and 13 b that house 2 a and 2 b are connected by a hinge 7.

  Further, as shown in FIGS. 3C and 3D, a locking hook 14 and a locking claw 15 are provided on each of the other sides of the case pieces 13a and 13b opposite to the side where the hinge 7 is provided. 3 and has a structure that allows the split-type magnetic core 2 to be attached to the cable by engaging them, a so-called snap-fit structure. Further, as shown in FIG. Tapers 14a and 15a are provided at the joint portion.

JP-A-7-122433 JP-A-8-153627

  However, in the above conventional example, the engaging portion between the locking hook and the locking claw is only provided with a taper, so that a force in the lateral direction (perpendicular to the engaging portion) is applied. There was a drawback that the joint part may come off.

  An object of the present invention is to solve the above-described problems and provide a noise absorbing device having a snap-fit structure in which a core case is unlikely to be detached from a cable even when a force is applied from the outside.

  The present invention includes a pair of core pieces obtained by dividing a cylindrical magnetic core into two in the longitudinal direction, and a core case that houses each of the core pieces and that is connected to the pair of case pieces divided into two in the longitudinal direction by hinges. A noise absorbing device comprising a locking hook on one side of the case piece opposite to the one side on which the hinge is provided, and a locking claw for engaging the locking hook on the other side of the case piece. In the device, the noise absorbing device is characterized in that a step portion is provided in each engaging portion of the locking hook and the locking claw.

  Moreover, this invention is said noise absorption apparatus characterized by providing the core press part in the bottom part which accommodates the said core piece of the said case piece.

  Further, the present invention is the above noise absorbing device, wherein cable holding portions are provided at both ends in the longitudinal direction of the case piece.

  Further, the present invention is provided with a locking recess at the inner edges of both ends in the longitudinal direction of the core piece, and a core holding claw that engages with the locking recess of the core piece at the bottom of the case piece. It is said noise absorber characterized by the above-mentioned.

  As described above, according to the present invention, it is possible to provide a noise absorbing device having a snap-fit structure in which the core case is unlikely to come off from the cable even when an external force is applied. In the present invention, in order to disengage the snap-fit structure, it is not necessary to lower the case piece provided with the locking hook or lower the case piece provided with the locking claw. Since the engagement between the locking hook and the locking claw cannot be released, the core case is unlikely to come off from the cable even when a force is applied from the outside.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1A and 1B are explanatory views of a noise absorbing device according to an embodiment of the present invention. FIG. 1A is an external perspective view, FIG. 1B is a plan view in a closed state, and FIG. ) Is a plan view in an open state, and FIG. 1D is a cross-sectional view taken along line BB in FIG. 1C. FIG. 2 is an explanatory diagram of a locking hook and a locking claw in the noise absorbing device according to the embodiment of the present invention, and FIG. 2 (a) is a cross-sectional view taken along line AA in FIG. 1 (b). 2 (b) is an enlarged cross-sectional view of a portion C in FIG. 2 (a). Components having the same configuration as the conventional example are denoted by the same reference numerals.

  The basic configuration is the same as that of the conventional noise absorber shown in FIG. That is, as shown in FIGS. 1B and 1C, the noise absorber 1 of the present invention includes a magnetic core 2 composed of a pair of core pieces 2a and 2b, and these core pieces 2a. 2b, and a core case 3 in which long sides of a pair of case pieces 3a and 3b that respectively accommodate 2b are connected by a hinge 7.

  The core pieces 2a and 2b are made of a magnetic material such as Ni—Zn ferrite, and the cylindrical magnetic core 2 is equally divided into two in the longitudinal direction. Locking recesses 20 are provided at the edges at both ends in the longitudinal direction on the concave side.

  The case pieces 3a and 3b are made of an insulating resin such as polypropylene resin, and are formed by dividing a substantially cylindrical body into two equal parts in the longitudinal direction. It is provided with a cable recess 33 [shown in FIG. 1 (a)] that is provided with an enclosed storage recess for storing the core pieces 2a and 2b and that is substantially semicircular on the side wall 32 and becomes substantially circular when closed. . Each of the case pieces 3 a and 3 b is provided with two cable holding portions 8, core pressing portions 9, and core holding claws 10. The cable holding portion 8 is formed by making a slit by making two cuts in the center of the wall portion 31 and forming a semicircular cutout at the tip thereof.

  As shown in FIG. 1 (d), the core pressing portion 9 is provided at the bottom of the housing recess, and has a plate-like structure that warps toward the core piece 2a as it approaches the wall from the center. Is provided with a convex portion 9a in contact with the core piece 2a. The core holding claws 10 are in the vicinity of the cable holding portions 8 at both ends of the storage recess and are formed continuously therewith. When the core piece 2a is stored in the core case 3, it engages with the locking recess 20 of the core piece 2a. It is a structure to do.

  Also, as shown in FIGS. 2 (a) and 2 (b), it is locked to the other long side opposite to the long side that is the edge of the side wall portion connected by the hinges of the case pieces 3a and 3b. When the hook 4 and the core case 3 are closed, locking claws 5 that engage with the hook 4 are formed. The locking hook 4 and the locking claw 5 have a structure that protrudes slightly from the joint surface when the core pieces 2a and 2b are accommodated, and the locking hook 4 has a rectangular shape with a through hole, and the locking claw Reference numeral 5 denotes a rectangular shape that can be fitted into the through hole. Steps 4a and 5a are provided at engaging portions (corresponding to the lower side in FIG. 2) of the locking hook 4 and the locking claw 5, respectively. The step 4a provided on the locking hook 4 is convex on the inner side (the side with the core pieces 2a, 2b), and the step 5a provided on the locking claw 5 is convex on the outer side. . Thereby, when the core case is closed, the stepped portions 4a and 5a are firmly fitted and held, and even if a force is applied from the outside, particularly in the lateral direction in FIG.

  As shown in FIG. 1 (a), the two core pieces are respectively stored in the storage recesses of the case pieces with the concave side up, the concave surface of one core piece is brought into contact with the cable in the longitudinal direction, and the other By closing the case piece and engaging the locking hook 4 and the locking claw 5, the two core pieces are pressed against the core pressing part 9 and at the same time, the cable is clamped by the cable holding part 8. In addition, the noise absorbing device 1 of the present invention is firmly held.

  The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention. For example, the shape of the core piece, the locking recess, the locking hook of the case piece, the locking claw, the shape of the stepped portion, and the installation positions thereof are not limited to the above embodiment.

Explanatory drawing of the noise absorber in one embodiment of this invention. FIG. 1A is an external perspective view. FIG. 1B is a plan view in a closed state. FIG.1 (c) is a top view of the open state. FIG.1 (d) is the BB sectional drawing of FIG.1 (c). Explanatory drawing of the latching hook in the noise absorber of one embodiment of this invention, and a latching claw. Fig.2 (a) is the sectional view on the AA line of FIG.1 (b). FIG.2 (b) is an expanded sectional view of the C section of Fig.2 (a). Explanatory drawing of the conventional noise absorber. FIG. 3A is a plan view of the opened state. FIG. 3B is a plan view in a closed state. FIG.3 (c) is the DD sectional view taken on the line of Fig.3 (a). FIG.3 (d) is the EE sectional view taken on the line of FIG.3 (b). FIG.3 (e) is an expanded sectional view of the F section of FIG.3 (d).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,11 Noise absorber 2 Magnetic body cores 2a and 2b Core pieces 3 and 13 Core cases 3a, 3b, 13a and 13b Case pieces 4 and 14 Locking hooks 4a and 5a Steps 5 and 15 Locking claws 7 Hinge 8 Cable Holding part 9 Core pressing part 9a Convex part 10 Core holding claws 14a, 5a Taper 20 Locking concave part 31 Wall part 32 Side wall part 33 Cable insertion part

Claims (4)

  A pair of core pieces obtained by dividing a cylindrical magnetic core into two in the longitudinal direction; and a core case that accommodates each of the core pieces and that is connected to the pair of case pieces divided into two in the longitudinal direction by hinges, In the noise absorbing device in which one of the case pieces is provided with a locking hook on the opposite side of the one side where the hinge is provided, and the other of the case pieces is provided with a locking claw that engages with the locking hook. A noise absorbing device, wherein stepped portions are provided at respective engaging portions of the locking hook and the locking claw.   The noise absorbing device according to claim 1, wherein a core pressing portion is provided at a bottom portion of the case piece that accommodates the core piece.   The noise absorbing device according to claim 1, wherein cable holding portions are provided at both ends in the longitudinal direction of the case piece.   2. A locking recess is provided at inner edges of both ends in the longitudinal direction of the core piece, and a core holding claw that engages with the locking recess of the core piece is provided at the bottom of the case piece. The noise absorbing device according to any one of?

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