JP3518359B2 - Ignition coil for internal combustion engine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition coil for an internal combustion engine used in an internal combustion engine of an automobile or the like, and in particular, an ignition coil for an internal combustion engine of an independent ignition type provided for each cylinder of the internal combustion engine. Regarding

[0002]

BACKGROUND OF THE INVENTION The inventor of the present application has made it possible to reduce the height of the secondary coil so as to prevent interference between adjacent ignition coils, and to have a secondary engine large enough to ignite an air-fuel mixture in a cylinder of an internal combustion engine. As an ignition coil for an internal combustion engine capable of obtaining energy, the following configuration has been developed.

That is, the ignition coil has a substantially disk-shaped primary coil portion formed by winding a primary coil winding and a substantially disk-shaped primary coil portion formed by winding a secondary coil winding. The secondary side coil portion and the secondary side coil portion are laminated and arranged so that their respective cores are aligned on the same straight line, and a flat coil body is provided.
In addition, a pair of cross iron core portions are attached so as to be sandwiched from both sides of the coil body, whereby a closed magnetic circuit passing from the central portion of the coil body to the outer peripheral four sides is formed. In this way, the coil body with the cross iron core attached is
It is configured to be housed in a case body and attached to an upper opening of a plug hole formed in a cylinder head of an internal combustion engine.

[0004]

By the way, in the ignition coil having the above-mentioned structure, the secondary high voltage generated in the secondary coil portion is transmitted through the high voltage terminal portion provided in the bottom plate portion of the case body. And is applied to the spark plug on the bottom plate of the plug hole.

In this case, it is necessary to electrically connect the secondary coil winding and the high-voltage terminal portion inside the case body. However, this ignition coil is required to have a small height. Therefore, there is a demand for a compact structure that can reduce the height of the ignition coil as the structure for connecting the secondary coil winding and the high-voltage terminal.

Further, in the case of such a compact structure, since the high voltage terminal portion and the coil body are arranged close to each other, it is necessary to prevent dielectric breakdown between them.

Therefore, the present invention has been made to solve the above-mentioned problems, and it is possible to connect the secondary coil winding and the high-voltage terminal portion in a more compact structure and to connect the coil body and the high-voltage terminal portion to each other. It is an object of the present invention to provide an ignition coil for an internal combustion engine capable of preventing the dielectric breakdown of the above.

[0008]

In order to solve the above problems, an ignition coil for an internal combustion engine according to claim 1 of the present invention has a substantially disk-shaped primary side around which a primary side coil winding is wound. The coil portion and the substantially disk-shaped secondary coil portion around which the secondary coil winding is wound are stacked and arranged so that their respective winding cores are aligned on the same straight line, and are orthogonal to the stacking direction. A coil body that is flattened in the direction in which the coil body is formed, an opening is formed in the upper surface of the coil body, and a case body that accommodates the coil body in which the flat direction is aligned horizontally is provided, and the center of the bottom plate portion of the case body. And a coil connecting portion that is embedded in the bottom plate portion of the case body and has one end side thereof protrudingly arranged in the case body so as to connect with the secondary coil winding. And the other end side is projectingly arranged in the connection part. It is provided with a buried terminal which is a high-voltage terminal portion for connection to the spark plug, in which one end of the secondary coil winding is connected to the coil connecting portion of the implant pin.

As described in claim 2, the coil connecting portion may be provided at a position visible from an upper opening of the case body when the coil body is housed in the case body. .

Further, as described in claim 3, the coil connecting portion may be provided with a slit extending downward from an upper end portion thereof to form a winding holding portion.

[0011]

DETAILED DESCRIPTION OF THE INVENTION An ignition coil for an internal combustion engine according to an embodiment of the present invention will be described below.

As shown in FIG. 1, the ignition coil 10 for an internal combustion engine is a so-called upper type which is installed and used above an opening of a plug hole Ha formed in a cylinder head H of an internal combustion engine. As shown in, a coil case 20A with an iron core is housed and arranged in a case body 12 made of resin.

In the coil portion 20A with an iron core, as shown in FIGS. 2 to 4, a substantially disk-shaped primary coil portion 45 and a substantially disk-shaped secondary coil portion 40 are arranged in the longitudinal direction. Cross core parts 30A and 30B as radial core parts are attached to the upper and lower surfaces of the flat coil body 20.

Here, FIG. 9 shows an example of connection of the ignition coil 10. As shown in FIG. 9, the ignition coil 10 includes an enamel wire wound around a primary coil portion 45 thereof. One end is pulled out from the case body 12 and electrically connected to the positive terminal of the battery B of the automobile. The negative terminal of the battery B is grounded. The other end of the enamel wire wound around the primary coil portion 45 is grounded via the case body 12 or a switching element S such as a power transistor provided outside the case body 12. The switching element S is ON / OFF controlled by receiving an ignition signal from an ECU or the like provided in the vehicle, so that the primary voltage from the battery B is intermittently applied to the primary coil portion 45. Composed.

Further, one end of the enameled wire wound around the secondary coil portion 40 is electrically connected to one end of the enameled wire wound around the primary coil portion 45 in the case body 12. . On the other hand, the other end of the enamel wire wound around the secondary coil portion 40 has the joint member 8 inside the plug hole Ha.
Is electrically connected to the spark plug P via. And
When the primary voltage is intermittently applied to the primary coil portion 45, a high voltage is induced in the secondary coil portion 40 by electromagnetic induction, and this high voltage is applied to the ignition plug P, so that the ignition plug P It becomes the structure which generates a spark.

Returning to FIGS. 1 to 4, the ignition coil 10
The configuration of each part of will be described.

As shown in FIGS. 2 to 4, the coil body 20 is formed by mounting or winding a primary coil portion 45 and a secondary coil portion 40 on a bobbin 22.

The bobbin 22 is formed by forming a pair of flange portions 24, 25 that spread in the radial direction at the lower end portion of the bobbin main body portion 23 in the shape of a short rectangular tube and the axially intermediate portion thereof.

Each of the collar portions 24 and 25 is formed in a substantially rectangular plate shape that matches the internal shape of the case body 12.
By winding an enameled wire as a secondary coil winding between the coils 4 and 25, a substantially disk-shaped secondary coil portion 40 is formed (see FIG. 5 for winding form). At this time, the ends of the winding and the ending of the enameled wire are pulled out from between the collar portions 24 and 25. The enamel wire used for the secondary coil portion 40 has a general structure in which an enamel paint is applied to the surface of a copper wire having a substantially circular cross section.

More specifically, the wire diameter is 0.04 to 0.1.
It is advisable to wind the enamel wire having a diameter of 8000 times 8000 to 15000 times to form the secondary coil portion 40.

Further, the upper end of the bobbin main body portion 23 projects above the upper collar portion 25, and the primary side coil portion 45 is attached thereto.

The primary side coil portion 45 is formed by stacking flat rectangular strip-shaped enameled wires, which are formed by applying enamel paint on the surface of a flat rectangular strip-shaped copper wire having a vertically-long rectangular cross section, as the primary coil winding in the thickness direction. It is formed into a disc shape by winding (see FIG. 6 for the winding form). At the center of the primary side coil portion 45, a substantially rectangular hole portion that allows the upper end portion of the bobbin main body portion 23 to be inserted therethrough is formed.

Further, the surface of the enamel wire used for the primary coil portion 45 is coated with a heat-welding or heat-fusible coating in order to impart self-welding property, and it is heated under a heated condition. By winding or heating after winding, the enamel wire is solidified in the form of being wound into a disc shape.

More specifically, the primary coil portion 45 may be formed by winding a flat strip enameled wire rolled at 1:15 to 1:35 90 to 180 times in the radial direction.

Here, the reason why the flat coil enameled wire is used for the primary coil portion 45 will be described.

For example, as shown in FIG. 5 (a cross section of one half of a coil), when an enameled wire 90 having a substantially circular cross section is used, how closely the enameled wire 90 is formed.
Even if it is wound, a useless space is created between the wound enamel wires. This leads to an increase in the size of the primary side coil portion, and is also a factor that hinders the dissipation of heat generated there.

On the other hand, like the present ignition coil, when a flat rectangular strip is used as the enamel wire 92 and the enamel wire is wound in such a manner as to be stacked in the thickness direction,
As shown in FIG. 6 (showing the shape of one half of the coil),
The enamel wire 92 can be tightly wound without a gap, the primary side coil portion 45 can be downsized, and the ignition coil can be thinned and the diameter thereof can be reduced, and the heat transfer property of heat generated there can be improved. This is because the heat dissipation is excellent.

The primary side coil portion 45 constructed as described above
Is arranged on the upper surface side of the collar portion 25 such that the upper end portion of the bobbin main body portion 23 is inserted into the hole portion of the central portion thereof, so that the primary side coil portion 45 and the secondary side coil portion 40 respectively have The winding cores are stacked so that they are aligned on the axis of the bobbin main body 23, whereby the flat coil body 20 is formed.

Here, the flat coil body 20 has a height dimension of 10 to 25 mm, and the ratio of the height dimension to the width dimension (minimum width dimension; dimension of minimum width portion in plan view shape) is 1: 2. ~
It is desirable that the ratio is within the range of 1: 6, more preferably 1: 3 to 1: 5. The reason for setting the upper limit of the height dimension to 25 mm is that the coil body 20 having a height dimension larger than this is used for the case body 12.
This is because the case body 12 generally interferes with other intake / exhaust system components in the vicinity of the cylinder head H, assuming that the case body 12 is housed in. The reason for setting the lower limit to 10 mm is
This is because the installation space is taken into consideration when the case body 12 accommodating the coil body 20 is provided with an accessory such as a connector portion 15, a fixing portion 16 (see FIG. 1, described later), and a switching element.

Then, both ends of the enamel wire wound around the primary side coil portion 45 and both ends of the enamel wire wound around the secondary side coil portion 40 are drawn out to the outside of the coil body 20, respectively. One end of the enamel wire of the side coil portion 45 and one end of the enamel wire of the secondary coil portion 40 are electrically connected to each other at the position of the outer peripheral edge of the collar portion 25 (not shown).

As shown in FIGS. 2 to 4, cruciform iron core portions 30A and 30B are attached to the upper and lower surfaces of the coil body 20 thus constructed, respectively.

The cross iron core portion 30B is formed by combining the substantially U-shaped iron core portions 31B and 36B formed by laminating electromagnetic steel plates in a substantially cross shape so that their intermediate portions intersect each other. At this time, a groove portion is formed in each of the overlapping portions of the respective iron core portions 31B and 36B, and the two iron core portions 31B and 36B are combined by fitting the groove portions on the opposite side to each other, whereby the cross iron core portion 30B The thickness dimension is kept small.

The iron core portion 31B arranged on the lower side at the intersection of the iron core portions 31B and 36B has a triangular prism shape having a taper surface inclined downward in the longitudinal direction of the iron core portion 31B on the lower surface side of the intersection. Core portion 34B is formed. The core portion 34B is adapted to be inserted into the bobbin main body portion 23 from above with the cross core portion 30B attached to the upper surface side of the coil body 20.

On the other hand, the lower cross iron core portion 30A has an upside-down shape with respect to the upper cross iron core portion 30B, that is, the substantially U-shaped iron core portions 31A and 36A are formed in the middle portion thereof. A core portion 34A is formed on the upper surface side of an iron core portion 36A arranged on the upper side at the intersecting portions by intersecting at the groove portions and combining in a substantially cross shape.

The core portion 34A is also inserted from below into the bobbin main body portion 23 with the cross core portion 30A attached to the lower surface side of the coil body 20.

Further, the cross core portions 30A, 30B
In the state where the coil body 20 is attached to each of the upper and lower surfaces of the coil body 20, the four upward end surfaces of the iron core portions 31A and 36A located on the lower side and the four downward end surfaces of the iron core portions 31B and 36B located on the upper side are The outer circumferences of the coil bodies 20 are configured to come into contact with each other.

Further, the tapered surfaces of the core portions 34A and 34B are provided in the bobbin main body portion 23 with permanent magnets 5 to be described later.
They are arranged in parallel with each other with an interval that can accommodate 0.

With these cross core portions 30A and 30B,
Four closed magnetic paths that pass from the central portion of the coil body 20 to the four outer circumferences are formed.

Here, the cross iron core portions 30A and 30B have
As the iron core portions 31A, 36A, 31B, 36B, it is preferable to use silicon plywood sheets having a plate thickness of 0.1 to 0.5 mm laminated to form a substantially U-shape, and the core portions 34A, 34B has an inner magnetic path having a cross-sectional area of 100 to 32.
As a 4 mm ^2, further cross core portions 30A, 3
It is preferable that the total cross-sectional area of the four outer magnetic paths formed around the outer circumference of the coil body 20 by 0B be 100 to 324 mm ² .

Further, as shown in FIGS. 3 and 4, the upper surface of the primary side coil portion 45 exposed on the upper surface side of the coil body 20 and the cross core portion 30 disposed on the upper surface side of the coil body 20.
A pair of insulating spacers 42 are interposed between the B core portion 36B and the iron core portion 36B.

The both insulating spacers 42 are made of an insulating material and are provided at respective positions sandwiching the bobbin main body 23 from both sides thereof. By this insulating spacer 42, the cross iron core portion 30B is positioned with respect to the primary side coil portion 45 while maintaining a sufficient insulating distance therebetween.

As shown in FIG. 1, FIG. 2, FIG. 7 and FIG. 8, the case body 12 is formed in a flat box shape with a square bottom surface and an open top surface. As shown by a chain double-dashed line, a fixing portion 16 for attaching the ignition coil 10 to the cylinder head H is provided, and
A connector portion 15 for electrically connecting the ignition coil 10 and the ECU or the like is provided on the front surface thereof.

A positioning groove 13 for fitting and positioning the cross iron core portion 30A is formed in a cross shape on the inner bottom surface 12a, and the lower end portion of the case body 12 is slightly tapered at the lower central portion. The finished connection portion 14 is vertically installed.

Here, the reason why the connecting portion 14 is formed in the central portion of the case body 12 will be explained. This is due to abnormal vibration of the case body 12 (resonance due to vibration of the internal combustion engine and the connecting portion 14). To prevent case vibration)
This is to prolong the life of the second grade product. For example, when the connecting portion 14 is formed near one corner of the case body 12, the case body 12 is attached to the cylinder head H via the connecting portion 14, so that the case body 12 is vibrated by the internal combustion engine. 12 will vibrate greatly.
However, when the connecting portion 14 is formed in the central portion of the case body 12 like this ignition coil, the connecting portion 14
This is because the mounting is performed in a well-balanced manner as the mounting portion, and the large vibration as described above is prevented.

Further, the bottom plate portion 12b of the case body 12 is
The embedded terminal 70 is embedded.

This embedded terminal 70 is formed by punching out a thin plate metal material to form a substantially strip shape in which both ends are bent in opposite directions. The middle part is the case body 1.
The second bottom plate portion 12b is embedded in a portion from one corner to the substantially central portion.

Of both the bent ends of the embedded terminal 70, the bent end on one corner side of the case body 12 is bent substantially vertically upward and is arranged so as to project into the case body 12 so that the coil connection portion 72 is provided. Has been finished. This coil connecting portion 72
When the coil portion 20A with an iron core is housed in the case body 12 (see the chain double-dashed line in FIG. 7), the coil portion with an iron core 2
It is arranged at a position visible from the upper opening of the case body 12 so as not to interfere with 0A.
When accommodating the coil portion 20A with the iron core therein, the accommodation work can be performed while checking the coil connection portion 72. Further, a slit extending downward is provided at the center of the upper end of the coil connecting portion 72 to form a winding sandwiching portion 73, and the winding sandwiching portion 73 has the other end portion of the secondary coil winding. By press-fitting, the other end of the secondary coil winding and the coil connecting portion 72 are electrically and mechanically connected.

The bent end portion of the embedded terminal 70 on the side of the central portion of the case body 12 is bent substantially vertically downward and is protruded from the lower surface of the bottom plate portion 12b of the case body 12 into the connecting portion 14 so that a high voltage is applied. The terminal portion 74 is finished. Then, when the upper end of the joint member 8 is fitted onto the connecting portion 14,
High voltage connection terminal 7 housed inside the joint member 8
Is electrically connected to the high voltage terminal portion 74 via the spring 6 (see FIG. 8).

Next, the method of assembling this ignition coil will be described. With the coil portion 20A with the iron core assembled as shown in FIG. 2, the other end of the enamel wire of the secondary coil portion 40 is embedded in the embedded terminal. The coil sandwiching portion 73 formed on the coil connecting portion 72 of the coil 70 is press-fitted, and soldering, spot welding, laser welding or the like is performed on these connecting portions. Then, the cross-shaped iron core portion 30A on the lower surface side is positioned and accommodated in the positioning groove portion 13 in the case body 12, and the coil portion 20A with an iron core is accommodated in the case body 12. At this time, the coil connecting portion 72
Since it is formed at a position visible from the upper opening of the case body 12, it can be housed while preventing mutual interference between the coil connecting portion 72 and the coil portion 20A with the iron core. In this way, the inside of the coil portion 20A with the iron core is attached to the case body 1
2 and then the coil portion 2 with an iron core is housed in the case body 12.
A liquid insulating resin is injected and filled so that the whole OA is immersed, and then heat treatment is performed to solidify. As a result, the coil portion 20 with the iron core is fixed in the case body 12. On this occasion,
As described above, since the insulating spacer 42 is interposed between the upper surface of the primary coil portion 45 and the cross iron core portion 30B, a sufficient insulation distance is provided between the primary coil portion 45 and the cross iron core portion 30B. Insulating resin is injected between them in a state in which they are secured. Further, since the insulating resin is injected between the primary coil portion 45 and the cross iron core portion 30B in this manner, the insulating resin sufficiently penetrates also between the layers of the enamel wire of the primary coil portion 45. . Thus, the insulation between the primary coil portion 45 and the cross core portion 30B is excellent, and the primary coil portion 45 can be prevented from losing its shape and can be positioned and fixed reliably. Further, since the primary coil portion 45 is pressed downward via the insulating spacer 42, the reliability of the positioning and fixing of the primary coil portion 45 can be increased in this respect as well.

In the ignition coil for an internal combustion engine configured as described above, the coil body 20 is formed by stacking the substantially disk-shaped primary side coil portion 45 and the substantially disk-shaped secondary side coil portion 40. Since it is formed, it is possible to obtain sufficiently large secondary energy to ignite the air-fuel mixture in the cylinder of the internal combustion engine. Further, since the shape of the coil body 20 is a flat shape formed by stacking the primary side coil portion 45 and the secondary side coil portion 40, the height dimension thereof is reduced and the coil body 20 is provided adjacently. Interference between the ignition coils can also be prevented.

Then, the embedded terminal 70 is embedded in the bottom plate portion 12b of the case body 12 accommodating the coil portion 20A with the iron core,
One end side of the embedded terminal 70 is projectingly arranged in the case body 12 to form a coil connecting portion 72 for connection with the secondary coil winding of the coil body 20, and the other end side thereof is projected into the connecting portion 14. High-voltage terminal 74 for connection with the ignition plug P
Therefore, the secondary coil winding and the high-voltage terminal portion 74 can be connected with a more compact structure, and the height dimension of the ignition coil can be further reduced.

Moreover, the structure is such that one embedded terminal 70 is provided.
Since this is only embedded in the bottom plate portion 12b of the case body 12, the configuration is very simple.

Since the embedded terminal 70 is embedded in the bottom plate portion 12b of the case body 12, the embedded terminal 70 has the thickness of the collar portion 24 between the secondary coil portion 40 and the embedded terminal 70. Since the insulating layer is formed by adding the thickness of the bottom plate portion 12b according to the embedding depth of 70, it is possible to more reliably prevent the dielectric breakdown between the two due to the potential difference between them.

Since the embedded terminal 70 is embedded in the bottom plate portion 12b of the case body 12 as described above, the embedded terminal 70 is less likely to be affected by the vibration of the internal combustion engine and the electrical connection between the embedded terminal 70 and the coil winding. Sex is stable.

Further, the coil connecting portion 72 is connected to the case body 12.
When accommodating the coil portion 20A with the iron core inside, the case body 1
Since it is arranged at a position visible from the upper opening of 2,
When the coil unit 20 with the iron core is housed in the case body 12,
Check the coil connecting portion 72 and check the coil connecting portion 72.
Since the housing operation can be performed while preventing the interference between the coil portion with the iron core and the core coil portion 20A, the ignition coil can be easily assembled.

Further, since the coil connecting portion 72 is provided with the slit to form the winding sandwiching portion 73, the coil body 2
The secondary coil winding of 0 and the coil connecting portion 72
Since the connection can be made with this, the connection work becomes easy also in this respect.

By the way, there is an ignition coil for an internal combustion engine, as shown in FIG. 10, in which a rectifying diode D is interposed between a secondary coil winding and an ignition plug P. Of the high voltage induced in the secondary coil section 40, the diode D only allows the voltage in one direction to ignite.
It is for applying to.

In such a case, the ignition coil shown in the modified examples of FIGS. 11 and 12 may be used.

That is, in the ignition coil of this modification, a predetermined interval is provided at one corner of the lower surface of the lower collar portion 24B of the coil body 20B (corresponding to the coil body 20 and the collar portion 24 of the first embodiment, respectively). A pair of mounting portions 78 are formed apart from each other. Each mounting portion 78 is formed with a groove portion 79 into which a pair of lead portions DL extending from both ends of the diode D can be inserted. The lead portions DL are respectively provided in the groove portions 79.
The diode is fixed to the collar portion 24 with an adhesive or the like in a state where the is inserted and positioned. At this time, the lead portion DL on one side is extended outward from the peripheral edge portion of the collar portion 24B.

A notch 24Ba is formed from one side of the collar 24B toward the center thereof, and the other end 40a of the winding start of the secondary coil winding passes through the notch 24Ba to the outside. The lead portion DL is pulled out and wound around the lead portion DL of the inside of the coil body 20 of both lead portions DL and soldered.

When the iron cored coil portion 20B is housed in the case body 12 described in the first embodiment, the lead terminal DL extending outward from the collar portion 24B is embedded in the embedded terminal 70.
The coil sandwiching portion 73 formed in the coil connecting portion 72 is clamped. As a result, the secondary coil winding can be electrically connected to the embedded terminal 70 via the diode D.

[0062]

As described above, according to the ignition coil for an internal combustion engine according to claim 1 of the present invention, the embedded terminal is embedded in the bottom plate portion of the case body that houses the coil body, and one end of the embedded terminal is embedded. The side is projectingly arranged in the case body to serve as a coil connecting part for connection with the secondary coil side winding, and the other end side is projectingly arranged in the connecting part to serve as a high voltage terminal part for connection with an ignition plug. Since one end of the secondary coil winding is connected to the coil connection part of the embedded terminal, the secondary coil winding and the high voltage terminal can be connected in a more compact configuration, and the height of the ignition coil can be reduced. Can be smaller.

Further, since the embedded terminal is embedded in the bottom plate portion of the case body, the thickness of the bottom plate portion corresponding to the embedding depth of the embedded terminal ensures the dielectric breakdown between the coil body and the high voltage terminal portion. Can be prevented.

According to a second aspect of the present invention, the coil connecting portion is arranged at a position visible from the upper opening of the case body when the coil body is housed in the case body.
When the coil body is housed in the case body, the housing work can be performed while checking the coil connection portion, so that the ignition coil can be easily assembled.

Further, when a slit extending downward from the upper end of the coil connecting portion is formed in the coil connecting portion to form a winding sandwiching portion, a secondary side coil winding of the coil body is formed. Since the secondary coil winding and the winding sandwiching portion can be connected by sandwiching the winding sandwiching portion, the connection work becomes easy.

[Brief description of drawings]

FIG. 1 is a diagram showing a mounted state of an internal combustion engine ignition coil according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing the above ignition coil.

FIG. 3 is an exploded perspective view of a coil body.

FIG. 4 is a cross-sectional view of a coil body.

FIG. 5 is a cross-sectional view showing a comparative example.

FIG. 6 is an enlarged cross-sectional view of a primary coil portion.

FIG. 7 is a plan view of a case body.

FIG. 8 is a cross-sectional view of a case body.

FIG. 9 is a wiring diagram of an ignition coil.

FIG. 10 is a configuration diagram of an ignition coil according to a modification.

FIG. 11 is an enlarged bottom view of the main parts of the coil body of the ignition coil of the same.

FIG. 12 is an enlarged side view of a main part of the coil body of the above.

[Explanation of symbols]

12 case body 14 Connection 20 coil body 40 Secondary coil 45 Primary coil part 70 Embedded terminal 72 Coil connection 74 High voltage terminal P spark plug

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01F 30/00-38/42

Claims (3)

(57) [Claims] 1. A substantially disk-shaped primary coil portion formed by winding a primary coil winding, and a substantially disk-shaped secondary coil portion formed by winding a secondary coil winding. Is a coil body that is laminated and arranged so that the respective cores are aligned on the same straight line and is finished to be flat in a direction orthogonal to the laminating direction, and an opening is formed in the upper surface, and the coil body is formed inside the opening. A case body accommodating the flat direction in a horizontal direction, a connecting portion hung downward from a substantially central portion of the bottom plate portion of the case body, and one end side of which is embedded in the bottom plate portion of the case body. A coil connecting portion for connecting with the secondary coil winding is provided so as to project in the case body, and the other end side is provided as a high voltage terminal portion for connecting with an ignition plug so as to project into the connecting portion. An embedded terminal, and the secondary coil winding Ignition coil end side is connected to the coil connection portion of the embedded terminal. 2. The ignition coil for an internal combustion engine according to claim 1, wherein the coil connecting portion is provided at a position visible from an upper opening of the case body when the coil body is housed in the case body. 3. The ignition coil for an internal combustion engine according to claim 1, wherein the coil connecting portion is provided with a slit extending downward from an upper end portion thereof to form a winding holding portion.