JP2012079443A - Terminal block - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a terminal block that increases the capacity between a plurality of terminal boards and enhances the noise reduction effect of ferrite core.SOLUTION: A terminal block for connecting a plurality of external wires serving as a power supply wire or signal wire, comprises: a power terminal board 2 and a ground terminal board 3 connected to each of the plurality of external wires and disposed face-to-face each other; and a ring-shaped ferrite core 10 for attenuating the superimposed noise on the plurality of external wires, wherein each vertical cutting surface between the face-to-face surfaces of the power source terminal 2 and the ground terminal 3 is a rectangle, the power terminal board 2 and the ground terminal board 3 are inserted in the ferrite core 10 so that the long sides of the rectangle cutting surfaces of the power terminal board 2 and the ground terminal board 3 are disposed face-to-face each other.

Description

  The present invention relates to a terminal block provided with a plurality of terminal plates for connecting a plurality of external wirings, and having the plurality of terminal plates inserted into a ferrite core for noise attenuation.

  Some conventional terminal blocks include a plurality of terminal pins and a ring-shaped ferrite core, and external noises that enter from the plurality of terminal pins are blocked by the ferrite core. Further, in the conventional terminal block, a plurality of terminal pins are inserted into the hollow portion of the ferrite core, and the terminal pins have a square cross section (see, for example, Patent Document 1).

JP 2006-317320 A

  However, in the conventional terminal block, since the cross-sectional shape of the plurality of terminal pins (hereinafter referred to as “terminal plates”) inserted in the hollow portion of the ferrite core is a square, the following problems are encountered. was there.

  When the plurality of terminal boards are power supply wiring or signal wiring, it is preferable to reduce noise by capacitive coupling between the plurality of terminal boards. In order to increase the capacity of the plurality of terminal boards, it is necessary to improve the area of the surface where the plurality of terminal boards face each other, or to reduce the distance between the plurality of terminal boards.

When multiple terminal boards are power lines, there are some that have a potential difference of several hundred volts between the terminal boards.
If the appropriate distance between the terminal boards (creeping distance) is not secured, the dielectric strength voltage will not be satisfied. For this reason, it becomes difficult to increase the capacity of the terminal boards by reducing the distance between the terminal boards.

  Therefore, in order to increase the capacity of the plurality of terminal boards, it is necessary to improve the area of the surface where the terminal boards face each other. If the cross-sectional shape is a square as in the conventional terminal block, it is necessary to increase the length of one side of the square in order to improve the area of the facing surface, and the terminal block also increases accordingly.

  In addition, the noise reduction effect of the ferrite core increases as the area where the plurality of terminal boards face the ferrite core increases. However, as described above, if the cross-sectional shape is a square as in the conventional terminal block, it is necessary to increase the length of one side of the square in order to improve the area of the facing surface, and accordingly the terminal block also increases. There's a problem.

  The present invention has been made in order to solve the conventional problems, and an object of the present invention is to provide a terminal block capable of increasing the noise reduction effect of the ferrite core while increasing the capacity between the plurality of terminal boards. And

  The present invention is a terminal block for connecting a plurality of external wirings composed of a ground wiring and a power supply or signal wiring, and a plurality of terminal boards that are connected to each other and face each other. And a ring-shaped ferrite core for attenuating noise superimposed on the plurality of external wirings, each of the plurality of terminal plates being rectangular in a plane perpendicular to a surface facing each other, and the plurality of terminals The plate is inserted into the ferrite core, and the plurality of terminal plates are arranged so that the long sides of the rectangle on the cut surface face each other.

  In the present invention, the cutting surfaces of the plurality of terminal boards are rectangular, and the plurality of terminal boards are arranged so that the long sides of the cutting faces face each other.

  Thereby, since the length of the 1 side which a some terminal board faces can be lengthened, the area of the surface which faces can be improved as a result. As a result, the area of the surface where the terminal boards face can be increased, and the capacity of the plurality of terminal boards can be increased.

  In addition, since multiple terminal boards face each other on the long side, the total length of the sides facing the ferrite core is calculated by subtracting the length of one long side from the total length of the rectangle. Length + 2 * short side length ". Compared to a square of the same area, the total length of the sides facing the ferrite core can be increased by using a rectangular shape.

  As described above, the present invention has an effect of increasing the noise reduction effect of the ferrite core while increasing the capacity between the plurality of terminal boards.

  In addition, by making it a rectangle, said advantageous effect is acquired compared with the case where it is set as the square of the same cross-sectional area as this rectangle. That is, since the same resistivity is obtained when the cross-sectional area is the same, the present invention can obtain the above effect without changing the resistivity.

The perspective view of the terminal block in Embodiment 1 of this invention Perspective view explaining the internal structure Sectional drawing in the X-axis-Y-axis plane explaining the internal structure The figure explaining the cross-sectional shape of the terminal board in Embodiment 1 of this invention Sectional drawing in the X-axis-Y-axis plane of the terminal block in Embodiment 2 of this invention

(Embodiment 1)
Hereinafter, a terminal block according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a perspective view of a terminal block according to Embodiment 1 of the present invention.

  First, the positional relationship used when describing the terminal block according to Embodiment 1 of the present invention will be described. The X axis in FIG. 1 is an axis whose positive direction is a negative direction in which a power terminal screw 9 and a ground terminal screw 8 to be described later of the terminal block 1 are inserted. This X axis is referred to as the front-rear direction. Further, the Y axis in FIG. 1 is perpendicular to the X axis and is directed to the right when viewed from the front (the surface in which the screw threads are visible when the power terminal screw 9 and the ground terminal screw 8 are assembled). An axis whose direction is a positive direction. This X axis is referred to as the left-right direction. Further, the Z axis in FIG. 1 is an axis that is perpendicular to the X axis and has a positive direction as a positive direction when viewed from the front of the terminal block 1. This Z axis is referred to as the vertical direction.

A line H in FIG. 1 indicates a “center line in the vertical direction”. The “center line in the vertical direction” is a straight line parallel to the Z-axis and passes through the approximate center in the Y-axis direction in the lateral width of the terminal block 1. Further, the line W in FIG. 1 indicates a “center line in the left-right direction”. The “center line in the left-right direction” is a straight line parallel to the X axis and passing through the approximate center in the Z axis direction in the vertical width of the terminal block 1.

  The terminal block 1 is connected to a plurality of external wirings that are power supply wirings. The plurality of external wirings are the power supply wiring 7 and the ground wiring 6 in FIG. For example, the positive side of the power supply is connected to the power supply wiring 7, and the negative side (or ground) of the power supply is connected to the ground wiring 6. The power supply connected to the power supply wiring 7 and the ground wiring 6 is not limited to a DC power supply but may be an AC power supply.

  As shown in FIG. 1B, the power supply wiring 7 and the ground wiring 6 are respectively connected to the power supply terminal board 2 and the ground terminal board 3 (corresponding to “a plurality of terminal boards”) by a power supply terminal screw 9 and a ground terminal screw 8. Fixed to. The opposite ends of the power supply terminal plate 2 and the ground terminal plate 3 with respect to the power supply wiring 7 and the ground wiring 6 in the Z-axis direction are fixed to the substrate 4 with solder or the like and are connected to a wiring pattern formed on the substrate 4. The power terminal plate 2 and the ground terminal plate 3 are inserted into the ferrite core 10.

  The power supply terminal plate 2, the ground terminal plate 3, and the ferrite core 10 are accommodated in the case 5. The inside of the case 5 is sealed with resin or the like. Examples of the resin include PPS (polyphenylene sulfide) and PBT (polybutylene terephthalate). By sealing with resin or the like in this way, it is possible to prevent the power supply terminal plate 2 and the ground terminal plate 3 from coming into contact with each other, and to ensure a withstand voltage, and the power supply terminal plate 2, the ground terminal plate 3, and The positional deviation of the ferrite core 10 can be prevented.

  Next, the power supply terminal board 2, the ground terminal board 3, and the ferrite core 10 which are the main components of the terminal block in Embodiment 1 will be described in detail with reference to FIG. FIG. 2 is a perspective view illustrating the internal structure of the terminal block according to the embodiment of the present invention.

  As shown in FIG. 2 (a), the power terminal plate 2 and the ground terminal plate 3 each have an end 2a and an end 3a in which holes for inserting the power terminal screw 9 and the ground terminal screw 8 are formed at one end. Have.

  Further, the power terminal plate 2 and the ground terminal plate 3 have a plate portion 2b and a plate portion 3b on the Z axis positive direction side, respectively. The plate portion 2b and the plate portion 3b are arranged so as to face each other on the surfaces having the largest areas.

  Each of the plate portion 2b and the plate portion 3b has a rectangular cut surface (cross section in the X-axis-Y-axis plane) when cut along a plane perpendicular to the surfaces facing each other. The plate portion 2b and the plate portion 3b are arranged so that the long sides of the rectangle on the cut surface face each other. The plate portion 2 b and the plate portion 3 b are arranged so as to be surrounded by the ferrite core 10.

  Further, the power terminal plate 2 and the ground terminal plate 3 have a claw portion 2c and a claw portion 3c at the opposite ends of the end portion 2a and the end portion 3a. The claw portion 2c and the claw portion 3c are inserted into holes formed in the substrate 4 and fixed with solder or the like.

  The ferrite core 10 is for attenuating noise superimposed on the power supply wiring 7 or the ground wiring 6. The ferrite core 10 is made of a metal oxide ferromagnet and has a higher specific resistance than that of a metal, so that it is not affected by overcurrent and is suitable for use at high frequencies.

  As shown in FIG. 2B, the ferrite core 10 in the present embodiment is formed in a ring shape. Here, the ring shape means a general one having a hollow cut surface, and is a concept including not only a circular cylinder but also a square cylinder.

  The power terminal plate 2 and the ground terminal plate 3 are disposed in the hollow portion of the cylindrical ferrite core 10. More specifically, the plate portion 2 b of the power terminal plate 2 and the plate portion 3 b of the ground terminal plate 3 are surrounded by the ferrite core 10. The effect of attenuating noise can be enhanced by surrounding the periphery of the plate portion 2b and plate portion 3b having the widest area among the power supply terminal plate 2 and the ground terminal plate 3 with the ferrite core 10. Next, the positional relationship of each part is described in detail using a cut surface (cut surface cut by a surface perpendicular to the surface facing each other on the plate portion 2b and the plate portion 3b) at the position indicated by the broken line H in FIG. explain.

  The arrangement of the power terminal plate 2, the ground terminal plate 3, and the ferrite core 10 will be described with reference to FIG. FIG. 3 is a cross-sectional view of the terminal block in the X-axis-Y-axis plane according to the first embodiment, and FIG. 4 is a diagram illustrating the cross-sectional shape of the terminal plate.

  As shown in FIG. 3, the cross-sectional shapes of the power supply terminal plate 2 and the ground terminal plate 3 are both rectangles having the same shape with a long side having a length W and a short side having a length L. The power supply terminal plate 2 and the ground terminal plate 3 are arranged facing each other so that the sides of the length W are almost completely opposed to each other.

  As shown in FIG. 3, the distance between the power terminal plate 2 and the ground terminal plate 3 is S. The separation distance S cannot be made smaller than a predetermined value because it is necessary to secure a creepage distance between the child terminal boards.

  The length DL1 is the distance between the power supply terminal plate 2 and the ferrite core 10 in the X-axis direction, and the length DL2 is the distance between the ground terminal plate 3 and the ferrite core 10 in the X-axis direction. The length DW1 is the distance between the power terminal plate 2 or ground terminal plate 3 and the ferrite core 10 in the negative Y-axis direction, and the length DW2 is the power terminal plate 2 or ground terminal plate 3 and ferrite in the Y-axis positive direction. The distance from the core 10.

  Any of the lengths DL1, DL2, DW1, and DW2 is preferably as short as possible. This is because as the ferrite core 10 and the terminal board are closer, the noise reduction effect of the ferrite core 10 is improved.

  Here, the relationship between the length W of the long side and the length L of the short side will be considered with reference to FIG. For example, suppose that each side of the square is an A side and a B side.

  First, as shown in case 1 in FIG. 4, consider a square having a length of 4 on the A side and a length of 4 on the B side. Since the long side of the cut surface of the power terminal plate 2 and the ground terminal plate 3 face each other, the total length of the sides facing the ferrite core 10 is “A side length + 2 * B side length”. Become. In case 1 (square), the total length of the sides facing the ferrite core 10 is 12.

Here, a case where the length of the A side is increased while maintaining the cross-sectional area (the length of the A side * the length of the B side) (case 2 to case 13) is considered. When the length of the A side is increased, the total length of the sides facing the ferrite core 10 is shortened from the case 2 to the case 4, but the total length of the sides facing the ferrite core 10 is increased from the case 5 to the case 13. It has become. That is, it can be seen that the total length of the sides facing the ferrite core 10 with the case 5 as a boundary is longer than a square having the same area. Case 5 is a case where the long side of the rectangle is a rectangle longer than four times the length of the short side of the rectangle. The above relationship can be generalized, and a rectangle that meets this condition is always longer than a square of the same area.

  As the total length of the sides facing the ferrite core 10 increases, the noise reduction effect of the ferrite core 10 increases.

  As described above, when the long side length W of the rectangle is longer than 4 times the short side length L of the rectangle, the total length of the sides facing the ferrite core 10 is a square having the same area. It can be made longer and the effect of noise reduction can be enhanced.

  As described above, in the terminal block according to Embodiment 1 of the present invention, the cut surfaces of the power supply terminal plate 2 and the ground terminal plate 3 are rectangular, and the long sides of the cut surfaces of the power supply terminal plate 2 and the ground terminal plate 3 are mutually connected. Arranged to face each other.

  In this way, the length of one side facing each other can be increased, and as a result, the area of the facing surface can be increased, so that the capacitance between the power supply terminal plate 2 and the ground terminal plate 3 can be increased. . Further, since the power terminal plate 2 and the ground terminal plate 3 face each other on the long side, the total length of the sides facing the ferrite core 10 can be increased.

  As described above, the present invention has the effect of increasing the noise reduction effect of the ferrite core 10 while increasing the capacitance between the power terminal plate 2 and the ground terminal plate 3.

  In addition, by making it a rectangle, said advantageous effect is acquired compared with the case where it is set as the square of the same cross-sectional area as this rectangle. That is, since the same resistivity is obtained when the cross-sectional area is the same, the present invention can obtain the above effect without changing the resistivity.

  The cross-sectional shapes of the power terminal plate 2 and the ground terminal plate 3 are the same in shape with the long side having the length W and the short side having the length L, so that the resistivity can be the same. Because.

  The power supply terminal plate 2 and the ground terminal plate 3 are arranged so that the sides of the length W face each other almost completely. This is because the capacity between them can be maximized.

(Embodiment 2)
Hereinafter, the terminal block according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 5 is a cross-sectional view of the terminal block in the X-axis-Y-axis plane according to Embodiment 2 of the present invention. In addition, about what has the structure similar to the structure of Embodiment 1, the same code | symbol is attached | subjected, the description is abbreviate | omitted, and a difference is explained in full detail.

  The difference between the first embodiment and the second embodiment is that, as explained in the first embodiment with reference to FIG. When arranged so as to face each other, the long sides are arranged so as to be almost completely opposed to each other. However, in the second embodiment, the power supply terminal plate 2 and the ground terminal plate 3 are arranged so that the long sides of the rectangle on the cut surface face each other. When arrange | positioning, it is the point arrange | positioned so that the length which the long side faces may become longer than the length of the short side of a rectangle.

  If it demonstrates using FIG. 5, the length which the long side faces will be M of FIG. This length is longer than the length L of the short side of the rectangle.

  By doing in this way, when the power terminal plate 2 and the ground terminal plate 3 have a rectangular cut surface, the power terminal plate 2 and the ground terminal plate 3 are arranged rather than arranging their short sides facing each other. Can be widened, and the capacity of the terminal board can be increased.

  In each of the above-described embodiments, the terminal block for connecting the power supply wiring and the ground wiring has been described. However, the present invention can also be applied as a terminal block for connecting the signal wiring and the ground wiring. This is because not only the power supply wiring but also the signal line is coupled to the ground wiring by a capacitor in order to reduce noise.

  In each of the above-described embodiments, the terminal block for connecting the two wirings of the power supply wiring and the ground wiring has been described. However, if the ground wiring is included, the number of terminals is larger than two (three or more). It may be a terminal block for connecting the wires. This is because if the ground wiring is included, the effect of the present invention, “capacitance between a plurality of terminal boards can be increased, and noise is reduced by capacitive coupling” is useful.

  The terminal block of the present invention is useful as a terminal block including a plurality of terminal plates for connecting a plurality of external wirings and inserting the plurality of terminal plates into a ferrite core for noise attenuation.

DESCRIPTION OF SYMBOLS 1 Terminal block 2 Power supply terminal board 3 Ground terminal board 4 Board | substrate 5 Case 6 Ground wiring 7 Power supply wiring 8 Ground terminal screw 9 Power supply terminal screw 10 Ferrite core

Claims (5)

A terminal block for connecting a plurality of external wirings composed of ground wiring and power supply or signal wiring,
A plurality of terminal boards that connect the plurality of external wirings and face each other;
A ring-shaped ferrite core for attenuating noise superimposed on the plurality of external wirings, and each of the cut surfaces obtained by cutting the plurality of terminal boards at a plane perpendicular to the surface facing each other is rectangular.
The terminal block, wherein the plurality of terminal plates are inserted into the ferrite core, and the plurality of terminal plates are arranged so that the long sides of the rectangle on the cut surface face each other. 2. The terminal block according to claim 1, wherein the plurality of terminal plates have rectangular shapes having the same cut surface when the plurality of terminal plates are cut perpendicularly to surfaces facing each other. 3. The terminal block according to claim 2, wherein the plurality of terminal plates are cut into a rectangular shape in which the length of the long side of the rectangle is longer than four times the length of the short side of the rectangle. 3. The terminal block according to claim 2, wherein when the plurality of terminal boards are arranged so that the long sides of the rectangle on the cut surface face each other, the long sides are arranged so as to be almost completely opposed to each other. When arranging the plurality of terminal boards so that the long sides of the rectangle on the cut surface face each other, the length of the long sides facing each other is longer than the length of the short side of the rectangle. The terminal block according to claim 2, wherein