JPH0541593Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an electromagnetic noise prevention structure in which a two-part cylindrical core for preventing induced noise is attached and held to a cable through which a signal or power supply current flows.

Cables that transmit electrical signals generate electromagnetic induction noise induced from surrounding noise radio waves, which can be superimposed on signals transmitted by the cable and become erroneous signals.
Furthermore, electromagnetic noise generated from equipment connected to the cable flows through the cable, becomes radio waves, and is dissipated into the air, causing malfunctions of other equipment. Furthermore, when electromagnetic noise is superimposed on a power cable, it can cause malfunctions in equipment connected to the power cable, or cause malfunctions in other equipment.

Normally, in order to prevent these electromagnetic noises, when manufacturing equipment, the input and output of the cables are connected to prevent electromagnetic noise from flowing onto the cables on the circuit board, and to prevent malfunctions within the equipment due to induction by external radio waves from the cables. A reactor wave circuit is built into the circuit, but if the electromagnetic environment is poor after the equipment is assembled, new electromagnetic noise countermeasures may be required. In this case, the cable is wrapped from both sides by a two-part cylindrical core with high relative magnetic permeability characteristics to form a closed magnetic path and add inductance to the cable. The present invention relates to an electromagnetic noise prevention structure for holding a cable using a two-part cylindrical core to prevent electromagnetic noise from occurring.

Conventionally, the structure for attaching a two-part cylindrical core to a cable for electromagnetic noise prevention uses a core holder 2 made of stainless steel spring material to hold the two-part cylindrical core 21 as shown in Figure 1. ,
It was possible to join the divided surfaces of the two-part cylindrical core 21, but in the conventional structure, when the two-part cylindrical core 21 is assembled into the cable 3, the joint surfaces of the cores are closely fitted and fixed without misalignment. It is troublesome to do so, and there is no structure for fixing the core holder 2 itself, including the two-part cylindrical core 21, to other parts. Furthermore, since the two-part cylindrical core 21 itself is exposed, there is a problem that the two-part cylindrical core 21 may be damaged.

The present invention improves the above-mentioned drawbacks, makes it easy to join the joining surfaces of the two divided cylindrical cores 21, and eliminates the positional shift of the joining surfaces of the two cores to be joined, so that it can be easily connected to the cable. It can be fixed and fixed to other parts of the core holder itself, and the part that holds and fits the two-part cylindrical core has a structure that does not easily come off.It holds the two-part cylindrical core and has high reliability for the cable. An object of the present invention is to provide an electromagnetic noise prevention structure that is easy to attach and detach.

In order to attach a 2-split cylindrical core to a cable, it is necessary to fix the 2-split cylindrical core to the cable, but in a core holder with a conventional structure, Although it is possible to join the cores, no consideration has been given to a structure in which a two-part cylindrical core is fixed to a cable, or a structure in which a two-part cylindrical core fixed to a cable is fixed to another object. In addition, in a core holder using stainless steel spring material, if the structure is to satisfy the joining of the joint surfaces of the two divided cylindrical cores and the fixation with the cable, the structure will be extremely complicated. The material of the core holder is made of resin, and it is possible to fix the 2-split cylindrical core to the cable, and the core holder itself can also be fixed to other objects. The joint surface is made to be in close contact with each other, and a resin holder having a core storage recess for storing the two-split cylindrical core is provided, so that the structure for preventing electromagnetic noise has a structure that does not easily come off.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows an embodiment of the electromagnetic noise prevention structure of the present invention, and is an external perspective view showing the structure of the two-part cylindrical core 1 and the resin holder (hereinafter referred to as holder) 9. FIG. The structure for preventing induced noise of the present invention shown in Fig. 2 stores the two-part cylindrical core 1 and the two-part cylindrical core 1, holds the cable, and fixes the entire resin holder assembled to another object. This is a resin holder configured to do so.

Two-part cylindrical core (hereinafter referred to as core) 1 in Fig. 2
The figure shows a shape in which a cylindrical core is divided into two parts. Two cores having the shape shown in the figure are used as a set, and a cable holding recess 7 is provided on the joint surface of the core to hold the cable in the longitudinal direction of the core. , claws 5 for preventing the core of the resin holder from falling off are provided in the grooves 71 at both ends of the bottom of the cable holding recess 7.
is locked, and the cable is held by the two cores so that the cable (not shown) is accommodated in the cable holding recess 7. The core used to prevent electromagnetic noise is a ferrite core with a high relative magnetic permeability, and is usually made of Ni-
A Zn-based ferrite core or a Mn-Zn-based ferrite core is used.

Resin holder 9 holding core 1 shown in FIG.
In this invention, a flexible and soft resin is used. Normally, the resin holder that houses the core 1 is made of hard resin such as phenol resin or ABS resin, but the resin holder 9 of the present invention is made of soft nylon rubber-containing resin or soft polypropylene. It uses resin.

In the present invention, a cable holding recess 7 for holding the cable is provided at the center in the longitudinal direction of the core 1, and grooves 71 are provided at both ends of the cable holding recess 7, and the resin holder 9 is provided with grooves 71 that engage with the cable holding recess 7. A claw 5 for preventing the core from falling off (hereinafter referred to as "claw") is provided to lock the core in the core housing recess 91 of the resin holder 9, thereby preventing the core 1 from falling off. First, the core 1 is placed on both sides of the resin holder 9 with the core joint surface, that is, the cable holding recess 7 facing upward, and the cable is passed through the cable holding recess in the center of the core, and the two-page spread resin holder 9 is inserted into the connecting part 13. Close using the fulcrum.
The core 1 is provided with a third surface 12 having a certain angle on the core joint surface, which is formed by chamfering the corners of the side (first surface) and back surface (second surface) of the core joint surface. Since the manufactured holder 9 is provided with a contact surface 11 that contacts the third surface, the core 1 housed in the holder is placed in the holder 9 with the third surface 12 guided and crimped to the contact surface 11. mated to. When the core 1 is stored in the core storage recess 91 of the holder 9, the third surface 12 comes into close contact with the abutment surface 11, and when the holders 9 are joined together using the connecting portion 13 as a fulcrum, the abutment surface 11 is brought into close contact with the abutment surface 11. Since the core storage recess 91 has a structure in which the bottom surface is inclined inward, the third surface 12 of the core 1 having a rounded back surface allows the core 1 to be held in the holder 9.
When the holder is placed in close contact with the core storage recess 91 of the holder, the contact surface 11 and the third surface 12 tightly connect the bonding surfaces of the core 1, and at the same time, the core 1 is placed in the center of the holder to be engaged. It functions to determine the position to be placed. When the holder 9 is closed and fixed, it is fixed by fitting into the holding part concave part 81 of the holding part 8 attached to the outer surface of one holder and the holding part convex part 82 attached to the outer surface of the other holder. do.

Also, when fixing the holder attached to the cable to another surface or other object, place the bent core body fixing part 6 parallel to the mounting surface of the holder and fix it to the other surface or object. .

As described above, in the electromagnetic noise prevention structure according to the present invention, the two-part cylindrical core housed in the resin holder has a third surface on the back surface, and the two corners of the bottom surface of the resin holder are provided with a third surface. has a contact surface that contacts the third surface, making it easy to join the two-part cylindrical core and fix it to the cable, and also to fix the resin holder itself to other objects. Therefore, the core joint surface does not shift due to vibration or changes over time, and there is little deterioration of the electromagnetic noise prevention characteristics.The core can be easily attached and detached from the holder, and the core is wrapped in a resin holder. The shape prevents the core from chipping.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of a conventional technique, in which FIG. 1a is a perspective view and FIG. 1b is a front view of a core holder. FIG. 2 is an exploded external perspective view showing a two-part cylindrical core and a resin holder that constitute the electromagnetic noise prevention structure according to the embodiment of the present invention. 1, 21...Two-split cylindrical core, 2...Core holder, 3...Cable, 4...Cable fixing claw,
5...Claw for preventing core falling off, 6...Bending core body fixing part, 7...Cable holding recess, 71...
Groove, 8...Holding portion, 81...Holding portion recess, 82
...Holding portion convex portion, 9...Resin holder, 10...
...Holding portion parallel bars, 11...Abutting surface, 12...Third surface, 13...Connecting portion, 91...Core storage recess.

Claims (1)

[Scope of utility model registration request] The joint surface of the split core is formed by a resin holder having a split core having a substantially rectangular cross section that holds the outer periphery of the cable and a cable holding recess provided on the core joint surface, and a core storage section that stores each of the split cores. An electromagnetic noise prevention structure that holds cables in cable holding recesses of the split cores facing each other,
A split core in which a third surface is provided between the side surface and the back surface of the core joint surface, grooves are provided at both longitudinal ends of the inner surface of the cable holding recess, and the split core is provided between the bottom surface of the core storage recess and the side surface of the core storage recess. A holder made of resin is provided with abutment surfaces that abut on the third surfaces of the core, and claws for preventing the core from falling off that protrude from the wall surfaces of both ends of the core storage recess and engage with the grooves of the split core. A structure for preventing electromagnetic noise.