JP2008034560A - Ignition coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition coil which can prevent the formation of voids on the periphery of a high-voltage side winding end portion, and can prevent leakage of a high-voltage current between a secondary coil and a primary coil. <P>SOLUTION: The ignition coil 1 is formed by filling the gap in a coil case 63 that contains a primary coil 2 and a secondary coil 4 with filling resin 15. The primary coil 2 is formed by winding an insulated primary winding 21 around the outer circumference of a primary spool 3. On the outer circumference, at the high-voltage side end portion 301 of the primary spool 3, a winding stop flange 31 is provided to project radially outward, in order to form a winding stop position A on the high-voltage side D1 of the primary winding 21. The winding stop flange 31 has an irregular shape on the axial end face 310 touching the primary winding 21. The filling resin 15 fills in between the high voltage side winding end portion 22 of the primary winding 21 at the winding stop position A and a corner portion 32 formed at the proximal portion on the axial end face 310 of the winding stop flange 31 via the recess in the irregular shape. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ignition coil used for generating a spark between a pair of electrodes in a spark plug in an internal combustion engine.

  In an ignition coil used for an internal combustion engine such as an engine, for example, a primary coil formed by winding a primary winding around a primary spool, and a secondary coil formed by winding a secondary winding around a secondary spool, They are arranged concentrically overlapping in the radial direction. In addition, a central core made of a magnetic material is arranged on the inner peripheral side of the primary coil and the secondary coil, and an outer peripheral core made of a magnetic material is arranged on the outer peripheral side of the primary coil and the secondary coil. A magnetic circuit passing through the core is formed.

Each gap in the ignition coil is filled with a filling resin such as an epoxy resin in order to fix and insulate each component. The filling resin is filled by setting the gap in the ignition coil in a vacuum state, injecting a filling resin in a liquid state in this vacuum state, and then curing the filling resin after the injection.
By the way, when a filling failure of the filling resin occurs in the ignition coil, a void due to this filling failure becomes a generation source of voids (bubbles). This void moves to the peripheral parts such as the primary coil and the secondary coil before the filling resin is cured, which may cause cracking or cause leakage of high voltage current in the secondary coil. There is a risk of becoming. For this reason, various measures have been taken to eliminate factors that hinder the injection properties of the filling resin.

  For example, in the ignition coil of Patent Document 1, a protrusion or groove is formed in the axial direction of the primary bobbin (primary spool), or a notch is formed in the flange of the primary bobbin in order to improve the impregnation property of the insulating resin. Or it forms a window. Accordingly, the insulating resin easily flows into the gap in the coil case via the protrusion or groove, or via the notch or window.

  However, in the above-described conventional ignition coil, the space at the corner portion of the winding collar that protrudes from the outer periphery of the high voltage side end of the primary spool is the high voltage side winding end of the primary winding that constitutes the primary coil. There is a risk of being blocked by the part. In this case, a void is formed in the space of the corner, and a high voltage current may be leaked between the secondary coil and the primary coil due to a crack generated from the void. .

JP 2003-83221 A

  The present invention has been made in view of such a conventional problem, and prevents a void from being formed around the end of the high voltage side winding, and a high voltage current between the secondary coil and the primary coil. It is an object of the present invention to provide an ignition coil that can prevent electric leakage from occurring.

The first invention is an ignition coil comprising a primary coil and a secondary coil housed in a coil case, and a filling resin filled in a gap in the coil case.
The primary coil is formed by winding a primary winding around the outer periphery of a primary spool made of resin having an annular cross section,
On the outer periphery at the axial end of the primary spool, a winding hook for projecting radially outward and forming the winding position of the primary winding is provided,
The winding stop portion has an uneven shape on the axial end surface in contact with the primary winding,
Between the winding end portion at the winding position of the primary winding and the corner portion formed at the base portion of the axial end surface of the winding hook portion, a concave portion in the concavo-convex shape is interposed. The ignition coil is filled with the filling resin (claim 1).

In the ignition coil according to the present invention, a concavo-convex shape is formed on the end surface in the axial direction of the winding rod portion of the primary spool. And the primary winding which comprises a primary coil is wound by the outer periphery of a primary spool, and the winding end part is stopped by the axial direction end surface in a winding stop part.
Further, the winding end portion is in contact with the convex portion on the concavo-convex axial end surface, and a gap is formed between the winding end portion and the concave portion on the axial end surface. By forming this gap, it is possible to prevent the winding end portion from forming a closed space that becomes a void at the corner portion of the base portion of the axial end surface.

As a result, the filling resin filled in the coil case is filled in the corners at the base of the axial end face through the recesses in the axial end face.
Therefore, no void is formed at the corner portion, and it is possible to prevent a high voltage current from leaking between the secondary coil and the primary coil due to a crack generated from the void.

  Therefore, according to the ignition coil of the present invention, a void is prevented from being formed around the winding end, and a high voltage current is prevented from leaking between the secondary coil and the primary coil. can do.

A second invention is an ignition coil comprising a primary coil and a secondary coil housed in a coil case, and a filling resin filled in a gap in the coil case.
The secondary coil is formed by winding a secondary winding on the outer periphery of a secondary spool made of resin having an annular cross section,
On the outer periphery of the secondary spool, partition portions protruding outward in the radial direction are formed at a plurality of positions in the axial direction, and the secondary winding includes a plurality of windings partitioned by the plurality of partition portions. It is continuously wound around each space,
Any one of the plurality of partition portions has an uneven shape on an axial end surface in contact with the secondary winding,
Between the winding end portion of the secondary winding and the corner portion formed at the base portion of the axial end surface of any of the partition portions, the filling resin is interposed through the recess in the uneven shape. The ignition coil is filled (claim 6).

In the ignition coil according to the present invention, a concavo-convex shape is formed on the axial end surface of one of the partitions of the secondary spool. And the secondary winding which comprises a secondary coil is wound continuously by each winding space partitioned by the partition part, The winding end part is stopped by the axial direction end surface in a partition part. Yes.
Further, the winding end portion of the secondary winding is in contact with the convex portion on the concavo-convex axial end surface, while a gap is formed between the winding end portion and the concave portion on the axial end surface. By forming this gap, it is possible to prevent a closed space that becomes a void from being formed at the corner portion of the base portion of the axial end face by the winding end portion of the secondary winding.

As a result, the filling resin filled in the coil case is filled in the corners at the base of the axial end face through the recesses in the axial end face.
Therefore, no void is formed at the corner portion, and it is possible to prevent a high voltage current from leaking between the secondary coil and the primary coil due to a crack generated from the void.

  Therefore, even with the ignition coil of the present invention, voids are prevented from being formed around the winding end, and high voltage current is prevented from leaking between the secondary coil and the primary coil. be able to.

A preferred embodiment in the first and second inventions described above will be described.
In the first and second inventions, the high voltage side is a side that generates a high voltage in the secondary coil, and is a side on which the spark plug is attached in the ignition coil.
In the first invention, the concavo-convex shape may be formed by forming concave portions at a plurality of locations in the circumferential direction from the axial end surface of the winding collar (Claim 2). Similarly, in the second invention, the uneven shape can be formed by forming concave portions at a plurality of locations in the circumferential direction from the axial end surface of any of the partition portions.
In these cases, an uneven shape can be easily formed on the axial end face.

Further, the winding stop portion is formed on an outer periphery of the high voltage side end portion of the primary spool, and the filling resin is provided on the high voltage side winding end at the winding position in the primary winding. It is possible to fill the gaps between the corners and the corners via the recesses in the irregular shape.
In this case, voids are prevented from forming around the high-voltage side winding end of the primary winding, and high-voltage current is prevented from leaking between the secondary coil and the primary coil. can do.

Further, the secondary coil is formed by winding a secondary winding around the outer periphery of a secondary spool made of resin having an annular cross section, and the axial end surface of the winding stop portion is formed by the secondary winding. Of these, it can be provided at a position facing the end portion of the high-voltage side winding located on the highest voltage side in the radial direction.
In this case, the distance between the high-voltage side winding end of the secondary coil and the high-voltage side winding end of the primary coil is close, and the high-voltage current is likely to leak. By preventing the formation of voids around the ends of the high-voltage side windings, the leakage of the high-voltage current can be effectively prevented.

Further, the primary winding is a round wire having a circular cross section, and the primary winding is a first-stage winding portion that is wound from the low voltage side end of the primary spool to the winding position; A second-stage winding portion that has been rewound from the winding position to the low-voltage side end, and among the primary windings, the high-voltage side winding end at the winding position is the above It can be formed by a winding portion located on the highest voltage side in the first-stage winding portion.
In this case, in the primary winding having the two-stage (two-layer) winding portions, it is possible to effectively prevent voids from being formed around the high-voltage side winding end portions.

In the second aspect of the invention, the winding partition located on the highest voltage side among the plurality of partitions has an uneven shape on the axial end surface in contact with the secondary winding, Between the high voltage side winding end located on the highest voltage side of the secondary winding and the corner formed at the base of the axial end surface of the winding partitioning portion, The filling resin can be filled through the recess (Claim 7).
In this case, the formation of voids around the high-voltage side winding end of the secondary winding is prevented, and the high-voltage current leaks between the secondary coil and the primary coil. Can be prevented.

Hereinafter, embodiments of the ignition coil according to the present invention will be described with reference to the drawings.
(Example 1)
As shown in FIG. 1, the ignition coil 1 of this example includes a primary coil 2 and a secondary coil 4 housed in a coil case 63 made of a thermoplastic resin, and a thermosetting resin is formed in a gap in the coil case 63. The filling resin 15 made of is filled.
As shown in FIG. 2, the primary coil 2 is formed by winding an insulating-coated primary winding 21 around the outer periphery of a primary spool 3 made of resin having an annular cross section. Further, on the outer periphery of the high-voltage side end 301 of the primary spool 3, there is provided a winding stop 31 that protrudes radially outward and forms a winding position A on the high-voltage side D <b> 1 of the primary winding 21. It is.

As shown in FIGS. 3 to 5, the winding stop 31 has an uneven shape on the axial end surface 310 that contacts the primary winding 21. As shown in FIG. 2, in the ignition coil 1 of this example, the high-voltage side winding end portion 22 at the winding position A in the primary winding 21 and the axial end surface 310 of the winding collar portion 31 are arranged. Between the corner 32 formed in the base, the filling resin 15 is filled through a concave portion 311 having a concave and convex shape.
3 is a perspective explanatory view showing a state in which the primary winding 21 is wound around the primary spool 3, and FIG. 4 is a cross-sectional explanatory view showing a state in which the primary winding 21 is wound around the primary spool 3. is there. FIG. 5 is an explanatory cross-sectional view showing the winding guard 31 when viewed from the axial direction D.

Hereinafter, the ignition coil 1 of this example will be described in detail with reference to FIGS.
As shown in FIG. 1, the ignition coil 1 of this example has a spark on one end side (high voltage side) D <b> 1 in the axial direction of a coil main body 11 in which a primary coil 2 and a secondary coil 4 are accommodated in a coil case 63. A plug mounting portion 13 for mounting a plug (not shown) is provided, and the ignition coil 1 is connected to the other axial end side (low voltage side) D2 of the coil body portion 11 with the electronic control unit of the engine outside the same. The connector part 12 for electrically connecting to (ECU) is provided.
The ignition coil 1 of this example is of a stick type in which the coil body portion 11 and the plug mounting portion 13 are disposed in the plug hole of the engine and the connector portion 12 is disposed outside the plug hole.

Further, the connector portion 12 is configured by disposing an igniter 75 for supplying power to the primary winding 21 in a connector case portion 71 made of a thermoplastic resin. Further, the connector portion 12 is formed with a connector connecting portion 72 protruding outward in the radial direction. The plurality of conductive pins in the igniter 75 are electrically connected to the conductive pins insert-molded in the connector connecting portion 72. In addition, the coil main body 11 of this example is fitted into a fitting hole 711 in the connector case 71 via a fitting member 64 made of a thermoplastic resin.
The igniter 75 has a power supply circuit that supplies power to the primary winding 21, and an ion current detection circuit that detects an ion current flowing through the secondary winding 41 through a pair of electrodes in the spark plug. ing.

  Moreover, the ignition coil 1 of this example is equipped with an ion current detection function. This ion current detection function is a function for detecting an ion current generated when ions generated when combustion is performed in the engine flow between a pair of electrodes in the spark plug. The ion current detection function is configured by an ion current detection circuit mounted on the igniter 75, and the ion current waveform detected by the ion current detection circuit is processed by an ion current detection processing circuit configured in the ECU. Thus, it is determined whether misfire has occurred during engine combustion.

  As shown in FIG. 1, the secondary coil 4 is formed by winding an insulating-coated secondary winding 41 around the outer periphery of a secondary spool 5 made of resin having an annular cross section. The secondary winding 41 has a smaller diameter than the primary winding 21, and the secondary winding 41 is wound around the secondary spool 5 with a greater number of turns than the primary winding 21. The secondary winding 41 of this example is wound by oblique winding. That is, the secondary winding 41 is formed by stacking a plurality of inclined winding layers wound toward the high voltage side D1 so as to reduce the winding diameter toward the high voltage side D1.

A rod-shaped central core 61 made of a magnetic material is arranged on the inner peripheral side of the primary coil 2 and the secondary coil 4, and a cylindrical shape made of a magnetic material is arranged on the outer peripheral side of the primary coil 2 and the secondary coil 4. The outer peripheral core 62 is arranged. In this example, the secondary coil 4 is inserted on the inner peripheral side of the primary coil 2, and the central core 61 is inserted on the inner peripheral side of the secondary coil 4. The coil case 63 has a thin cylindrical shape and is disposed between the outer periphery of the primary coil 2 and the outer core 62.
The central core 61 in this example is formed by laminating flat electromagnetic steel plates (silicon steel plates or the like) in the radial direction of the ignition coil 1 and having a substantially circular cross section. The outer peripheral core 62 of this example is formed by laminating electromagnetic steel plates (silicon steel plates or the like) formed in a cylindrical shape along the shape of the outer peripheral surface of the coil case 63 in the radial direction. A stress relaxation sheet 613 made of PET (polyethylene terephthalate) or the like is wound around the outer periphery of the central core 61.

3-5, the uneven | corrugated shape formed in the axial direction end surface 310 of the winding hook part 31 of this example is on the high voltage side D1 in the axial direction D in several places of the circumferential direction from the axial direction end surface 310. As shown in FIG. It is provided by a recess 311 that is cut away. A convex portion 312 is formed between the concave portions 311 in the circumferential direction of the axial end surface 310. In this example, the recesses 311 are formed at two locations in the circumferential direction of the axial end surface 310.
Moreover, the recessed part 311 formed in the axial direction end surface 310 of the winding stop part 31 can also be formed in four places of the circumferential direction of the axial direction end surface 310, as shown in FIG. 6, FIG. Further, as shown in the figure, the circumferential length of the concave portion 311 may be made longer than the circumferential length of the convex portion 312 so that the filling resin 15 is easily filled into the corner portion 32 of the winding collar 31. it can.

  As shown in FIG. 2, in the ignition coil 1 of this example, the axial end surface 310 of the winding stop 31 of the primary spool 3 is the highest among the secondary windings 41 wound around the secondary spool 5. It is provided at a position facing the high voltage side winding end portion 42 located on the voltage side D1 in the radial direction. That is, the axial end surface 310 of the winding hook 31 faces the axial end surface of the winding hook 56 that forms the high voltage side winding position of the secondary winding 41 in the secondary spool 5 in the radial direction. At the position.

  As shown in FIG. 4, the primary winding 21 and the secondary winding 41 are round wires having a circular cross section. The primary winding 21 includes a first-stage winding portion 21A that is wound from the low-voltage side end portion 302 of the primary spool 3 to the winding position A, and a second winding portion that is rewound from the winding position A to the low-voltage side end portion 302. A stage winding portion 21B. The high-voltage side winding end portion 22 at the winding position A in the primary winding 21 is formed by the winding portion located on the highest voltage side D1 in the first-stage winding portion 21A.

As shown in FIG. 1, the plug attachment portion 13 is formed by attaching a rubber plug cap 81 to a cap attachment portion 33 formed to extend from the end of the primary spool 3 on the high voltage side D1.
Further, as shown in FIG. 2, a high voltage terminal for connecting a high voltage side winding end 42 of the secondary winding 41 is connected to a terminal mounting portion 52 formed at the end of the high voltage side D <b> 1 of the secondary spool 5. (Secondary terminal) 82 is attached. In addition, a coil spring 83 that contacts a terminal portion of a spark plug (not shown) is attached to the high voltage terminal 82 in a conductive state. The high voltage side winding end portion 42 of the secondary winding 41 is electrically connected to the spark plug terminal portion via the high voltage terminal 82 and the coil spring 83.

The high voltage terminal 82 is sandwiched between a terminal mounting portion 52 in the secondary spool 5 and a holding portion 331 formed on the inner peripheral side of the cap mounting portion 33 of the primary spool 3.
In addition, the spark plug (not shown) engages with a hollow hole 811 formed in the plug cap 81 at the lever portion, and the terminal portion formed at the tip of the lever portion is in contact with the coil spring 83 in the engine cylinder. Fixed to the head cover.

Further, as shown in FIG. 1, a filling resin 15 is filled in a gap in the ignition coil 1 surrounded by the coil case 63, the connector portion 12, the primary spool 3, the high voltage terminal 82, and the like. The filling resin 15 in this example is an epoxy resin as a thermosetting resin. As shown in FIG. 2, the filling resin 15 includes a gap between the coil case 63 and the primary spool 3, a gap between the primary windings 21, and a recess 311 on the axial end surface 310 of the winding collar 31. In addition, the corner portions 32 and the like are also filled.
Note that the filling resin 15 in the ignition coil 1 is assembled after the components of the ignition coil 1 are assembled, the gap in the ignition coil 1 is evacuated, and the liquid epoxy resin is placed in the vacuum gap. And then cured by curing the epoxy resin.

  In the ignition coil 1, when a current is passed through the primary winding 21 by a pulsed spark generation signal from the ECU, a magnetic field passing through the center core 61 and the outer core 62 is formed. Next, when the current flowing through the primary winding 21 is interrupted, an induction magnetic field that passes through the central core 61 and the outer peripheral core 62 is formed in a direction opposite to the magnetic field formation direction. Then, due to the formation of the induction magnetic field, a high-voltage induced electromotive force (counterelectromotive force) is generated in the secondary winding 41, and a spark is generated between a pair of electrodes in the spark plug attached to the ignition coil 1. it can.

In the ignition coil 1 of the present example, a concavo-convex shape is formed on the axial end surface 310 of the winding collar 31 of the primary spool 3. And the primary winding 21 which comprises the primary coil 2 is wound by the outer periphery of the primary spool 3, and the high voltage side winding end part 22 (winding part in 21 A of first-stage winding parts) is a winding stop part. 31 is wound by an axial end face 310.
The high-voltage side winding end portion 22 is in contact with the convex portion 312 on the concave and convex axial end surface 310, while a gap is formed between the high voltage side winding end portion 22 and the concave portion 311 on the axial end surface 310. By forming this gap, it is possible to prevent the high-voltage side winding end portion 22 from forming a closed space that becomes a void in the corner portion 32 at the base portion of the axial end surface 310.

Thus, the filling resin 15 filled in the coil case 63 is filled in the corner portion 32 at the base portion of the axial end surface 310 via the recess 311 in the axial end surface 310.
For this reason, no void is formed in the corner 32, and it is possible to prevent a high voltage current from leaking between the secondary coil 4 and the primary coil 2 due to a crack generated from the void. it can.

  Therefore, according to the ignition coil 1 of the present example, voids are prevented from being formed around the high-voltage side winding end portion 22 in the primary winding 21, and between the secondary coil 4 and the primary coil 2. Therefore, it is possible to prevent the high voltage current from leaking.

  In Example 1, an uneven shape was provided on the axial end surface 310 of the winding collar 31 for forming the winding position on the high voltage side D1 of the primary spool 3. On the other hand, the concavo-convex shape can also be provided on the axial end surface (see B portion in FIG. 1) of the winding hook portion for forming the winding position on the low voltage side of the primary spool 3. It can also be provided on the end surface in the axial direction (see section C in FIG. 1) of the winding collar for forming the winding position on the low voltage side D2 of the spool 5. Also by these, a void is not formed in the corner | angular part in the axial direction end surface of a winding stopper part, but generation | occurrence | production of the electric leakage by the crack which made this void a reference point can be prevented.

(Example 2)
In this example, as shown in FIG. 8, voids are prevented from being formed around the high-voltage side winding end portion 42 in the secondary winding 41 of the secondary coil 4.
On the outer periphery of the secondary spool 4 of the secondary coil 4 of this example, partition portions 53 projecting radially outward are formed at a plurality of locations in the axial direction D, and the secondary winding 41 of this example is It is continuously wound around a plurality of winding spaces 55 partitioned by a plurality of partition portions 53.

  Further, among the plurality of partition portions 53, the winding partition portion 53 </ b> A located on the highest voltage side D <b> 1 has an uneven shape on the axial end surface 530 that contacts the secondary winding 41. And between the high voltage side coil | winding edge part 42 located in the highest voltage side D1 among the secondary windings 41, and the corner | angular part 54 formed in the base part of the axial direction end surface 530 of 53 A of latching partition parts. Is filled with the filling resin 15 through the concave portion 531 in the concave-convex shape.

  In the ignition coil 1 of the present example, the high-voltage side winding end portion 42 of the secondary winding 41 is in contact with the convex portion 532 on the concave and convex axial end surface 530, while the concave portion 531 on the axial end surface 530. A gap is formed between the two. By forming this gap, it is possible to prevent the high-voltage side winding end portion 42 from forming a closed space that becomes a void in the corner portion 54 at the base portion of the axial end surface 530.

  Accordingly, the filling resin 15 filled in the coil case 63 is filled in the corner portion 54 at the base portion of the axial end surface 530 through the recess 531 in the axial end surface 530. Therefore, no void is formed in the corner portion 54, and it is possible to prevent a high voltage current from leaking between the secondary coil 4 and the primary coil 2 due to a crack generated from the void. it can.

Therefore, according to the ignition coil 1 of the present example, it is possible to prevent voids from being formed around the high-voltage side winding end portion 42 in the secondary winding 41, and the secondary coil 4 and the primary coil 2. It is possible to prevent a high voltage current from leaking between them.
Also in this example, other configurations are the same as those of the first embodiment, and the same effects as those of the first embodiment can be obtained.

In Example 2, an uneven shape was provided on the axial end face 530 of the winding partition 53A located on the highest voltage side D1 among the plurality of partitions 53. On the other hand, the concavo-convex shape can also be provided on the axial end surface of the other partition portion 53. Also by this, a void is not formed in the corner | angular part in the axial direction end surface of the other partition part 53, but generation | occurrence | production of the electric leakage by the crack which made this void a reference point can be prevented.
The uneven shape provided on the axial end surface of the other partition 53 is not limited to the axial end surface on the low voltage side D2 of the partition 53, but can be provided on the axial end surface of the high voltage side D1 of the partition 53. .

Sectional explanatory drawing which shows the ignition coil in Example 1. FIG. Sectional explanatory drawing which shows the periphery of the edge part by the side of the high voltage in a coil main-body part in Example 1. FIG. FIG. 3 is a perspective explanatory view showing a state where the primary winding is wound around the outer periphery of the primary spool in the first embodiment. Sectional explanatory drawing which expands and shows the periphery of the winding stop part of the state which wound the primary winding in the outer periphery of the primary spool in Example 1. FIG. Sectional explanatory drawing which shows the periphery of the winding stopper part in a primary spool in Example 1 seen from the axial direction. FIG. 3 is an explanatory perspective view illustrating a state where the primary winding is wound around the outer periphery of another primary spool in the first embodiment. Sectional explanatory drawing which shows the periphery of the winding stop part in the other primary spool in Example 1 in the state seen from the axial direction. FIG. 9 is a perspective explanatory view showing a state in which a secondary winding is wound around the outer periphery of a secondary spool in the second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ignition coil 11 Coil main-body part 15 Filling resin 2 Primary coil 21 Primary winding 21A First stage winding part 21B Second stage winding part 22 High voltage side winding end part 3 Primary spool 31 Winding rod part 310 Axial direction End surface 311 Concave part 312 Convex part 32 Corner part 4 Secondary coil 41 Secondary winding 42 High voltage side winding end part 5 Secondary spool 53 Partition part 53A Winding partition part 530 Axial end face 531 Concave part 532 Convex part 54 Corner part 55 Space for Winding 61 Central Core 62 Outer Core 63 Coil Case D Axial Direction D1 High Voltage Side D2 Low Voltage Side

Claims (7)

In an ignition coil comprising a primary coil and a secondary coil housed in a coil case, and a filling resin filled in a gap in the coil case,
The primary coil is formed by winding a primary winding around the outer periphery of a primary spool made of resin having an annular cross section,
On the outer periphery at the axial end of the primary spool, a winding hook for projecting radially outward and forming the winding position of the primary winding is provided,
The winding stop portion has an uneven shape on the axial end surface in contact with the primary winding,
Between the winding end portion at the winding position of the primary winding and the corner portion formed at the base portion of the axial end surface of the winding hook portion, a concave portion in the concavo-convex shape is interposed. An ignition coil filled with the filling resin.   2. The ignition coil according to claim 1, wherein the concavo-convex shape is formed by forming concave portions at a plurality of locations in a circumferential direction from the axial end surface of the winding collar. In Claim 1 or 2, the said winding stop part is formed in the perimeter at the high voltage side edge part of the above-mentioned primary spool,
The filling resin is filled through a concave portion in the concavo-convex shape between the high-voltage side winding end portion and the corner portion in the winding position of the primary winding. Ignition coil to play. The secondary coil according to claim 3, wherein the secondary coil is formed by winding a secondary winding around the outer periphery of a secondary spool made of a resin having an annular cross section.
The ignition end characterized in that the axial end face of the winding stop portion is provided at a position opposed in a radial direction to a high voltage side winding end located on the highest voltage side of the secondary winding. coil. In Claim 3 or 4, the primary winding is a round wire having a circular cross section,
The primary winding includes a first-stage winding portion wound from the lower voltage side end of the primary spool to the winding position, and a second stage wound back from the winding position to the low-voltage side end. Winding part,
An ignition coil characterized in that, among the primary windings, the high-voltage side winding end portion at the winding position is formed by a winding portion located on the highest voltage side in the first-stage winding portion. . In an ignition coil comprising a primary coil and a secondary coil housed in a coil case, and a filling resin filled in a gap in the coil case,
The secondary coil is formed by winding a secondary winding on the outer periphery of a secondary spool made of resin having an annular cross section,
On the outer periphery of the secondary spool, partition portions protruding outward in the radial direction are formed at a plurality of positions in the axial direction, and the secondary winding includes a plurality of windings partitioned by the plurality of partition portions. It is continuously wound around each space,
Any one of the plurality of partition portions has an uneven shape on an axial end surface in contact with the secondary winding,
Between the winding end portion of the secondary winding and the corner portion formed at the base portion of the axial end surface of any of the partition portions, the filling resin is interposed through the recess in the uneven shape. An ignition coil that is filled. In Claim 6, the winding partition part located in the highest voltage side among a plurality of above-mentioned partition parts has concavo-convex shape in the axial direction end surface which contacts the above-mentioned secondary winding,
Between the high voltage side winding end located on the highest voltage side of the secondary winding and the corner formed at the base of the axial end surface of the winding partition, the uneven shape An ignition coil, wherein the filling resin is filled through a recess in the battery.

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