JP2007335569A - Ignition coil for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition coil for internal combustion engine which is capable of obtaining big secondary voltage and secondary energy by increasing the sectional area of a permanent magnet piece without changing the size thereof. <P>SOLUTION: The ignition coil 11 for internal combustion engine with the permanent magnet piece is arranged between one end 18a of a laminated center core unit 18 wound by a primary coil 14 as well as a secondary coil 16 and a laminated annular core unit 19 with the laminated center core unit 18 arranged inside thereof. The surface of one end 18a of the laminated center core unit 18 is divided into two planes 18b, 18c in the widthwise direction of the laminated center core unit 18 which are formed so as to be projected toward the side of the laminated annular core unit 19. The part of laminated annular core unit 19 opposed to the one end 18a of the laminated center core unit 18 is formed so as to be a recess 19a formed by two parallel opposed planes 19b, 19c opposed to the two planes 18b, 18c, and permanent magnet pieces 20B, 20C are arranged respectively between the planes 18b, 18c and the parallel opposed planes 19b, 19c. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ignition coil for an internal combustion engine that supplies a high voltage for generating spark discharge to an ignition plug of an internal combustion engine such as an automobile engine.

  FIG. 2 is a cross-sectional view showing a schematic configuration of the internal combustion engine ignition coil.

In FIG. 2, reference numeral 11 denotes an ignition coil for an internal combustion engine. On the outer periphery of the insulating case 12, the primary coil 14 wound around the outer periphery of the primary coil bobbin 13 and the secondary coil bobbin 15 accommodated in the insulating case 12. The wound secondary coil 16, the laminated core 17 that magnetically couples the primary coil 14 and the secondary coil 16 to form a closed magnetic circuit, and the socket portion 12s located on the side surface of the insulating case 12 are provided. A plurality of low-voltage terminals (primary terminals) 21 and a cylindrical high-pressure tower portion 12t positioned at the lower end of the insulating case 12 are attached by, for example, press-fitting so as to close the high-pressure tower portion 12t. High voltage terminal (secondary terminal) 22 and insulation that injects (fills) into the insulating case 12 and solidifies, thereby performing high-voltage insulation between the components housed in the insulating case 12 , For example, and an insulating resin 23 such as thermosetting resin.
The laminated core 17 includes a laminated center core 18 that passes through the primary and secondary coil bobbins 13 and 15 and the primary and secondary coils 14 and 16, and the laminated center core 18 is located on the inner side. The coil bobbins 13 and 15 and the laminated annular core 19 surrounding the primary and secondary coils 14 and 16 are configured.
Reference numeral 20 denotes a permanent magnet piece, and when the primary coil 14 is energized between one end surface (one end surface) of the laminated center core portion 18 and the inner side surface of the laminated annular core portion 19, the inside of the laminated center core portion 18 is provided. Are arranged so as to generate a magnetic flux in the opposite direction to the magnetic flux generated in the laminated center core 18.
In addition, the primary coil 14, the secondary coil 16, the some low voltage terminal 21, and the high voltage terminal 22 are connected so that a predetermined circuit may be comprised (for example, refer patent document 1).

  FIG. 3 is a perspective view showing an example of a conventional laminated iron core and permanent magnet piece. The same reference numerals are given to the same or corresponding parts as in FIG.

  In FIG. 3, one end of the laminated center core 18 is cut by sequentially increasing the width in the left-right direction (annular direction of the laminated annular core 19) toward the opposed laminated annular core 19 (inner side surface). The area is increasing.

JP 2004-363357 A

The conventional internal combustion engine ignition coil 11 has a laminated center core portion that generates a magnetic flux in the direction opposite to the magnetic flux generated in the laminated center core portion 18 when the primary coil 14 is energized. The permanent magnet piece 20 is disposed between one end face of the laminated iron core 18 and the inner side face of the laminated annular core 19 to increase the change in magnetic flux when the energization of the primary coil 14 is interrupted. I try to get the next energy.
However, when the facing area between the one end surface of the laminated center core portion 18 and the inner side surface of the laminated annular core portion 19 is increased, the sectional area of the permanent magnet piece 20 is also increased, so that the permanent magnet piece 20 is easily broken. Further, since the magnetic force of the permanent magnet piece 20 is increased, the production yield in the manufacturing process of the permanent magnet piece 20, for example, the process of cutting, magnetization, etc. is deteriorated, and the manufacturing cost of the permanent magnet piece 20 is increased (increased). )

  The present invention has been made to solve the above-mentioned disadvantages, and can increase the cross-sectional area of the permanent magnet piece without changing the size, thereby obtaining a large secondary voltage and secondary energy. An ignition coil for an engine is provided.

The present invention is as follows.
(1) In an internal combustion engine ignition coil in which a permanent magnet piece is arranged between one end of a center iron core portion around which a primary coil and a secondary coil are wound, and an annular iron core portion on which the center iron core portion is arranged inside, The surface of the center core portion is divided into a plurality of planes in the width direction of the center core portion so as to protrude toward the annular core portion, and the annular core portion facing one end of the center core portion. This portion is a recess formed by a plurality of opposed planes opposed to the plurality of planes, and permanent magnet pieces are arranged between the respective planes and the respective opposed planes.
(2) In an internal combustion engine ignition coil in which a permanent magnet piece is disposed between one end of a center core portion around which a primary coil and a secondary coil are wound, and an annular core portion on which the center core portion is disposed inside. A surface of one end of the center core portion is divided into a plurality of planes in the width direction of the center core portion to form an approximate semi-cylindrical surface projecting toward the annular core portion, and one end of the center core portion The portions of the annular core portions facing each other are formed as recesses having approximate semi-cylindrical surfaces formed by a plurality of facing planes facing the plurality of planes, and permanent magnet pieces are respectively provided between the planes and the facing planes. It is characterized by arranging.

  According to this invention, the surface of one end of the center core portion is divided into a plurality of planes in the width direction of the center core portion and formed so as to protrude toward the annular core portion, and the annular core facing one end of the center core portion. Since the portion is a recess formed by a plurality of opposing planes facing a plurality of planes, and a permanent magnet piece is disposed between each plane and each opposing plane, or the surface of one end of the center core portion Is divided into a plurality of planes in the width direction of the center core portion to form an approximate semi-cylindrical surface projecting toward the annular core portion, and a portion of the annular core portion facing one end of the center core portion Since the recess has an approximate semi-cylindrical surface formed by a plurality of opposed planes facing the plane, and the permanent magnet pieces are arranged between each plane and each opposed plane, the size of the ignition coil for the internal combustion engine is changed. Without increasing the cross-sectional area of the permanent magnet piece The secondary voltage and the secondary energy of the ignition coil for the internal combustion engine can be increased, and the size of each permanent magnet piece can be reduced by dividing the permanent magnet piece into a plurality of pieces. Therefore, the production yield in the manufacturing process, such as cutting and magnetization, is improved, the manufacturing cost of the permanent magnet piece is reduced, and the manufacturing cost of the ignition coil for the internal combustion engine is reduced.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a perspective view showing an example of a laminated core and a permanent magnet piece in an ignition coil for an internal combustion engine according to an embodiment of the present invention. The same or corresponding parts as those in FIGS. Description is omitted.

In FIG. 1, the laminated center core portion 18 has one end 18 a having an increased cross-sectional area protruding toward the laminated annular core portion 19 side, and a plurality of surfaces of the one end 18 a in the width direction of the laminated center core portion 18, for example, 2 It is divided into two planes 18b and 18c.
Therefore, the two planes 18b and 18c are inclined planes that protrude from the both ends in the width direction of the laminated center core portion 18 toward the center portion in the width direction of the laminated center core portion 18 toward the laminated annular core portion 19 side. .
Further, the portion of the laminated annular core portion 19 that faces the one end 18a of the laminated center core portion 18 is a recess 19a formed by two parallel facing planes 19b and 19c that are parallel to the two planes 18b and 18c. ing.
The permanent magnet piece 20B is arranged between the planes 18b and 18c and the parallel opposing planes 19b and 19c, that is, between the plane 18b and the parallel opposing plane 19b, and between the plane 18c and the parallel opposing plane 19c. A permanent magnet piece 20C is disposed on the surface.
The planes 18b and 18c and the parallel opposing planes 19b and 19c form an approximate semi-cylindrical surface with the same axis as the center, that is, the ends in the width direction of the planes 18b and 18c and the plane 18b on the same circle. , 18c are located, concentric with the circle where the ends of the planes 18b, 18c are located, the ends of the parallel facing planes 19b, 19c in the width direction and the intersections of the parallel facing planes 19b, 19c are located. .

According to one embodiment of the present invention, the surface of the one end 18a is divided into two planes 18b and 18c in the width direction of the laminated center core portion 18 so as to protrude toward the laminated annular core portion 19 side. A portion of the laminated annular core 19 that faces the one end 18a of the core 18 is a recess 19a formed by two parallel facing planes 19b and 19c that are parallel to the two planes 18b and 18c, and is parallel to the plane 18b. Since the permanent magnet piece 20B is arranged between the plane 19b and the permanent magnet piece 20C is arranged between the plane 18c and the parallel opposing plane 19c, the permanent magnet pieces 20B and 20C can be disconnected without changing the size. The area can be increased.
Therefore, the secondary voltage and the secondary energy of the ignition coil for the internal combustion engine can be increased by increasing the cross-sectional area of the permanent magnet pieces 20B and 20C without changing the size of the ignition coil for the internal combustion engine. it can.
Further, by dividing the permanent magnet pieces 20B and 20C into two permanent magnet pieces 20B and 20C, the size of each permanent magnet piece 20B and 20C can be reduced, so that the production yield in the manufacturing process, for example, the process of cutting, magnetization, etc. is increased. As a result, the manufacturing cost of the permanent magnet pieces 20B and 20C is reduced, and the manufacturing cost of the ignition coil for the internal combustion engine is reduced.

In the above-described embodiment, an example in which the iron core is configured by the laminated center core portion 18 and the laminated annular core portion 19 has been shown. However, the iron core is configured by, for example, a center core portion and an annular core portion formed of a metal block. Alternatively, other configurations such as a center core portion and a ring core portion formed of fired metal blocks may be used.
Moreover, although the example which made the lamination | stacking center iron core part 18 and the lamination | stacking cyclic | annular iron core part 19 single-piece | unit was shown, it is set as the structure which divided | segmented the cyclic | annular core part into multiple, or while dividing | segmenting the cyclic | annular core part into multiple, and dividing into multiple Other configurations, such as a configuration in which the center core portion is integrally provided in a part of the annular core portion, may be employed.
Moreover, although the example which has arrange | positioned the permanent magnet pieces 20B and 20C between the two planes 18b and 18c and the two parallel opposing planes 19b and 19c has been shown, the number of the planes and the parallel opposing planes may be equal to two or more. For example, there may be three, four, five, or more than two, and when the plane and the parallel opposing plane are two or more, each plane and the parallel opposing plane are set on the same axis. It is desirable to provide an approximate semi-cylindrical surface with a center.
Moreover, although the example in which the planes 18b and 18c and the parallel opposing planes 19b and 19c form an approximate semi-cylindrical surface centered on the same axis has been shown, a plurality of planes form an approximate semi-cylindrical surface and a plurality of planes A plurality of planes and a plurality of opposed planes are formed (provided) such that the opposed planes facing each other form an approximate semi-cylindrical surface having an axis different from the approximate semi-cylindrical surface formed by the plurality of planes. The same effect can be obtained even if a plurality of pairs (provided) with opposing opposing planes are formed (provided).
In addition, although an example in which the cross-sectional area is increased by sequentially increasing the width of one end portion of the laminated center core portion 18 toward the opposing laminated annular core portion 19 (inner side surface) in the left-right direction is shown. Even if the cross-sectional area of one end of the iron core is not increased, that is, the cross-sectional area of the one end can be applied to the same cross-sectional area as that of the other part.

FIG. 1 is a perspective view showing an example of a laminated iron core and permanent magnet pieces in an internal combustion engine ignition coil according to an embodiment of the present invention. It is sectional drawing which shows schematic structure of the ignition coil for internal combustion engines. It is a perspective view which shows an example of the conventional laminated iron core and a permanent magnet piece.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Internal combustion engine ignition coil 12 Insulation case 12s Socket part 12t High voltage tower part 13 Primary coil bobbin 14 Primary coil 15 Secondary coil bobbin 16 Secondary coil 17 Laminated core 18 Laminated center core 18a One end 18b Plane 18c Plane 19 Laminated annular core 19a Recess 19b Parallel facing plane 19c Parallel facing plane 20 Permanent magnet piece 20B Permanent magnet piece 20C Permanent magnet piece 21 Low voltage terminal (primary terminal)
22 High voltage terminal (secondary terminal)
23 Insulating resin (insulating material)

Claims (2)

In an internal combustion engine ignition coil in which a permanent magnet piece is disposed between one end of a center core portion around which a primary coil and a secondary coil are wound, and an annular core portion on which the center core portion is disposed on the inside.
Forming one end surface of the center core portion into a plurality of planes in the width direction of the center core portion and projecting toward the annular core portion side;
A portion of the annular core portion facing one end of the center core portion is a recess formed by a plurality of facing planes facing the plurality of planes,
A permanent magnet piece is disposed between each plane and each opposing plane,
An ignition coil for an internal combustion engine. In an internal combustion engine ignition coil in which a permanent magnet piece is disposed between one end of a center core portion around which a primary coil and a secondary coil are wound, and an annular core portion on which the center core portion is disposed on the inside.
The surface of one end of the center core portion is divided into a plurality of planes in the width direction of the center core portion, and is formed to be an approximate semi-cylindrical surface protruding toward the annular core portion side,
A portion of the annular core portion facing one end of the center core portion is a recess having an approximate semi-cylindrical surface formed by a plurality of facing planes facing the plurality of planes,
A permanent magnet piece is disposed between each plane and each opposing plane,
An ignition coil for an internal combustion engine.

Images