JP2002048046A - Ignition coil for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability and the reliability of a switching module, and to improve the working efficiency when assembling an ignition coil. SOLUTION: This ignition coil 10 for internal combustion engine has a primary coil 2, a secondary coil 3 and a module housing chamber 6 for housing a switching module 5, and an insulating case 1 thereof is provided with a primary connector 7 in the peripheral wall. Each insulating case side end 71m-74m of external connecting terminals 71-74 provided in the primary connector 7 and each terminal 2a and 2b of a starting end and a terminal end of the primary connector 7 are arranged with the same or the nearly same space with the space between each terminal 5a-5e of the switching module 5.

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 having a module accommodating chamber for accommodating a primary coil, a secondary coil and a switching module in an insulating case, and having a primary connector on a peripheral wall of the insulating case. It is.

[0002]

FIG. 13 is a top view showing an example of a conventional ignition coil for an internal combustion engine. In the figure, a conventional ignition coil 100 for an internal combustion engine includes a primary coil 102, a secondary coil 103, and a module accommodation chamber 1 in an insulating case 101.
And the primary connector 1 on the peripheral wall of the insulating case 101.
07.

A switching module (igniter) 105 is accommodated in a module accommodating chamber 106, and terminals 105a and 105 are provided from the upper end surface of the igniter 105.
b, 105c, 105d, and 105e protrude.
On the other hand, the external connection terminals 171 and 1 of the primary connector 107
72, 173, and 174 are arranged so that one ends thereof are in contact with the module storage chamber 106 inside the insulating case 101 as end portions 171m, 172m, 173m, and 174m on the case side. Further, the primary coil 102
The start end 102a and the end 102b of the winding are arranged near the module accommodating chamber 106.

The terminal 105 of the igniter 105
a, 105b, 105c, 105d, and 105e are connected to the case-side ends 171m, 172m, 173m, and 174m of the external connection terminals 171, 172, 173, and 174, and the start end 102a and the end 102b of the primary coil, so that ignition occurs. The function as a coil is exhibited.

By the way, each terminal 10 of the igniter 105
The intervals between 5a, 105b, 105c, 105d, and 105e often follow the standard package size as a semiconductor, and are determined by the idea of miniaturization of the igniter alone. Also, the external connection terminals 171 and 17
The spacing between 2,173,174 is often restricted by the shape of the vehicle-side connector 109 connected to the vehicle-side harness, and the case-side end portions 171m, 172m, 173m,
The positioning of 174 m is also restricted accordingly. Furthermore, the positions of the start end 102a and the end 102b of the winding of the primary coil 102 are often determined by the convenience of production equipment.

In such a situation, if the igniter 105 is to be built in as an ignition coil, the positions of the terminals are restricted, so that the terminals 105a, 105b, 105 of the igniter 105 which are originally extended straight.
As shown in FIG. 13, c and 105d cannot be connected to each other unless they are formed and bent in a complicated manner in a top view.

On the other hand, the above-described ignition coil 100 for an internal combustion engine is used.
In the above, after the built-in components such as the primary coil 102, the secondary coil 103, and the igniter 105 are assembled, the insulating case 101 is filled with an insulating resin 116 to seal these built-in components. Containment room 106
Similarly, the igniter 105 is sealed by filling the insulating resin 117. The insulating resin 116 injected into the insulating case 101 generally has a linear expansion coefficient of 40 × 10 ^−6.
/ ° C. is used, whereas the epoxy resin having a linear expansion coefficient of about 15 × 10 ⁻⁶ / ° C. is used as the insulating resin 117 injected into the module accommodating chamber 106.

[0008]

However, as described above, if the terminals 105a, 105b, 105c, and 105d of the igniter 105 are formed and bent at the time of assembling the ignition coil, the working efficiency at the time of assembling deteriorates. Then, if extreme forming is performed, each of the terminals 105a, 105a
5b, 105c, and 105d will lose their strength,
This may cause the durability and reliability of the igniter 105 to decrease.

Further, each terminal 105 of the igniter 105
a, 105b, 105c, and 105d cannot be handled by forming the external connection terminals 171, 172, and 1
73 and 174 need to be bent or crossed in a complicated manner, which may cause a short circuit between terminals.

On the other hand, as described above, when the two types of epoxy resins 116 and 117 having different linear expansion coefficients are solidified via the side wall of the module accommodating chamber 106 or in direct contact therewith, the linear expansion coefficient of the epoxy resin 116 or 117 is reduced. The difference causes thermal stress due to repeated cooling and heating during use, and according to experiments, the igniter 105
, A stress of about 40 MPa may be applied to the igniter 105, which may cause poor connection or disconnection in the electrical connection portion and the wiring of the igniter 105. Can be reduced. As a method of alleviating the thermal stress, there is an example in which the igniter 105 is covered with a bag or a cushioning material on a tube before assembling the ignition coil. However, any of these methods is difficult to automate, and significantly impairs the workability during assembly.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has an advantage that the durability and reliability of an igniter can be improved, and the working efficiency at the time of assembling an ignition coil can be improved. It is intended to provide a coil.

[0012]

Means for Solving the Problems To achieve the above object, the invention according to claim 1 has a module housing chamber for housing a primary coil, a secondary coil, and a switching module in an insulating case, In an ignition coil for an internal combustion engine having a primary connector on a peripheral wall of an insulating case, an end of the external connection terminal provided on the primary connector on the insulating case side, a distance between terminals of a starting end and a terminating end of the primary coil, and a switching module Are arranged at the same or substantially the same intervals.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the switching module has an aspect ratio of 1.5 to 1.9: 1 in a front view.
Degree.

According to a third aspect of the present invention, there is provided an ignition for an internal combustion engine having a module housing chamber for housing a primary coil, a secondary coil, and a switching module in an insulating case, and having a primary connector on a peripheral wall of the insulating case. The coil is characterized in that an insulating resin is injected into the insulating case and hardened, and the module accommodating chamber is filled with a flexible heat-resistant and cushioning material.

[0015]

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

1 to 3 show the configuration of an ignition coil for an internal combustion engine according to the present invention. FIG. 1 is a top view, and FIG.
FIG. 3 is a sectional view taken along line II-II of FIG. 1. 4 to 6 are views showing only the configuration of the insulating case, FIG. 4 is a top view, FIG. 5 is a sectional view taken along line III-III of FIG. 4, and FIG. 6 is a sectional view taken along line IV-IV of FIG. is there. further,
7 to 9 are views showing a state in the middle of assembling before mounting the igniter. FIG. 7 is a top view, FIG. 8 is a sectional view taken along line VV of FIG. 7, and FIG. 9 is a line VI-VI of FIG. It is sectional drawing. FIG.
0 and FIG. 11 show the structure of the igniter.
Is a top view of the igniter, and FIG. 11 is a front view of the igniter.

In these figures, an ignition coil 10 for an internal combustion engine according to the present invention has a primary coil 2
It has a secondary coil 3 and a module accommodation room 6, and has a primary connector 7 on the peripheral wall of the insulating case 1. An iron core 4 is fitted into the primary coil 2, and a high voltage generated in the secondary coil 3 via the iron core 4 is output to a spark plug (not shown) via a high voltage terminal 12 of a secondary connector 11. It is supposed to be.

A switching module (igniter) 5 is accommodated in the module accommodating chamber 6, and terminals 5a, 5b, 5c, 5d, 5e protrude from the upper end surface of the igniter 5. As shown in FIG. 11, the igniter 5 has an aspect ratio of about 1.5 to 1.9: 1 in a front view.

After assembling the internal components such as the primary coil 2, the secondary coil 3 and the igniter 5 into the insulating case 1, the insulating case 1 is filled with an insulating resin 16 to seal these internal components. In the module accommodating chamber 6, in the module accommodating chamber 6, a soft buffer material 17 having sufficient heat resistance, for example, a silicone rubber having a hardness of about 10 to 30 (measured by a type A durometer), a soft epoxy resin, urethane The igniter 5 is covered with a resin or the like and solidified.

External connection terminals 71, 7 of primary connector 7
Each of 2, 73, 74 is formed by bending a long and thin strip in the length direction thereof, and working with a punching press so that one end side and the other end side are generally displaced in the width direction when viewed from above. It is formed and disposed along the inner peripheral wall of the module housing chamber 6, and its case-side ends 71 m and 72 are provided.
m, 73 m and 74 m are provided so as to slightly protrude from the module storage chamber 6.

The primary coil 2 has its winding end 2 a and end 2 b arranged near the module housing 6.

Then, the igniter 5 is housed in the module housing chamber 6, and its terminals 5a, 5b, 5c, 5d, 5e are provided.
Are connected to external connection terminals 71, 72, as shown in FIG.
Case side ends 71m, 72m, 73m, 7 of 73, 74
4m and the connection to the start end 2a and the end 2b of the primary coil 2, a function as an ignition coil is exhibited. By the way, in the embodiment of the present invention, the terminal 5 of the igniter 5
a, 5b, 5c, 5d, and 5e are arranged at a distance of D1 from each other (FIG. 11).

On the other hand, as shown in FIG.
As described above, the external connection terminals 71, 72, 73, 74 are formed so as to be displaced from each other at the both ends in the length direction as viewed from above, and the case side ends 71m, 7
2m, 73m, and 74m are arranged at equal intervals D2. The terminal interval D of the igniter 5
1 and the terminal interval D2 of the case-side end 71m and the like are set to be the same or substantially the same. The space between the case-side end 74m and the terminal end 2b of the primary coil 2 is also set to be the distance D2. Furthermore, the starting end 2 of the primary coil 2
“a” is arranged in the extending direction of the terminal 5a of the igniter 5 with respect to the case-side end 71m. Therefore, the case side ends 71 of the external connection terminals 71, 72, 73, 74 are provided.
m, 72m, 73m, 74m and the start end 2a and the end 2b of the primary coil 2 are arranged corresponding to the positions of the terminals 5a, 5b, 5c, 5d of the igniter 5 housed in the module housing chamber 6, respectively.

As described above, in the embodiment of the present invention, the terminals 5a to 5e of the igniter 5 and the external connection terminals 71 to
74-side end portions 71m to 74m and primary coil 2
Of the igniter 5 are arranged at the same or substantially the same distance from the start end 2a and the end 2b of the igniter 5.
The b, 5c, 5d, and 5e can be connected as they are without forcibly forming and bending, so that the ignition coil can be assembled quickly and the work efficiency can be improved. In addition, failure of the igniter 5 caused by excessive bending of the terminal can be reduced, and durability and reliability can be reliably improved.

As described above, the external connection terminals 71 to 74
If the terminal intervals on the igniter 5 side with respect to the case-side end portions 71m to 74m and the start end 2a and the end end 2b of the primary coil 2 are made equal or substantially equal, the terminal interval becomes wider than that of a conventional standard igniter. It may lead to an increase in size as an igniter, but in this invention,
Since the aspect ratio of the igniter 5 is set to about 1.5 to 1.9: 1, the increase in size is minimized, and the igniter 5 has a smaller aspect ratio than the conventional igniter having an aspect ratio of 0.6 to 1: 1. Also, the height of the ignition coil can be suppressed.

Further, since the module housing chamber 6 is filled with a flexible buffer material 17 having sufficient heat resistance, the linear expansion with the insulating resin 16 on the side of the insulating case 1 which has conventionally occurred. Thermal stress due to the difference in coefficient can be greatly reduced, and therefore, deformation of the igniter 5 hardly occurs, and it is possible to reliably prevent poor connection and disconnection in the electrical connection portion and the wiring. From this point, the durability and reliability of the igniter 5 can be improved. Conventionally, to reduce thermal stress,
The work of covering the igniter 5 with a bag or a tube and providing a buffer area is not necessary, and from this point, the work efficiency in assembling the ignition coil can be improved.

[0027]

Since the present invention has the above-described configuration,
The following effects can be obtained.

According to the first aspect of the present invention, the ends of the external connection terminals provided on the primary connector on the insulating case side, the intervals between the start and end terminals of the primary coil, and the terminals of the switching module are provided. Since the intervals are arranged at the same or almost the same, each terminal of the switching module can be connected as it is without forcibly forming and bending the terminals, so that the ignition coil can be assembled quickly. The work efficiency can be improved. In addition, the failure of the switching module caused by the excessive bending of the terminal can be reduced, and the durability and reliability can be reliably improved.

Further, if it is attempted to make the terminal spacing on the switching module side the same or substantially the same as the end of the external connection terminal on the insulating case side or the like without changing the conventional standard switching module, the conventional standard switching module is used. The switching module may be wider than the terminal spacing of the switching module, which may lead to an increase in the size of the switching module. However, in the invention according to the second aspect, the vertical and horizontal dimensional ratio of the switching module is 1.5 to 1.9. : 1, so that this increase in size can be minimized, and the height dimension of the ignition coil can be suppressed as compared with the conventional switching module having an aspect ratio of 0.6 to 1: 1. The size of the coil can be reduced.

Further, according to the third aspect of the present invention, since the module accommodating chamber is filled with a buffer material having sufficient heat resistance and flexibility, thermal stress which has been conventionally generated is greatly reduced. Therefore, the deformation of the switching module hardly occurs, and it is possible to reliably prevent the occurrence of connection failure and disconnection in the electrical connection portion and the wiring. Durability and reliability can be improved.
In addition, in order to reduce the thermal stress in the related art, it is not necessary to cover the switching module with a bag or a tube and to provide a buffer region. From this point, the work efficiency in assembling the ignition coil can be improved.

[Brief description of the drawings]

FIG. 1 is a top view showing a configuration of an ignition coil for an internal combustion engine of the present invention.

FIG. 2 is a sectional view taken along line II of FIG.

FIG. 3 is a sectional view taken along line II-II of FIG.

FIG. 4 is a top view showing the configuration of only the insulating case.

FIG. 5 is a sectional view taken along line III-III of FIG. 4;

FIG. 6 is a sectional view taken along line IV-IV of FIG. 4;

FIG. 7 is a top view showing a state during assembly before mounting the igniter.

FIG. 8 is a sectional view taken along line VV of FIG. 7;

FIG. 9 is a sectional view taken along line VI-VI of FIG. 7;

FIG. 10 is a top view showing the configuration of the igniter.

FIG. 11 is a front view showing a configuration of an igniter.

FIG. 12 is a diagram showing a circuit configuration of an ignition coil for an internal combustion engine of the present invention.

FIG. 13 is a top view showing an example of a conventional ignition coil for an internal combustion engine.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Insulation case 2 Primary coil 2a Starting end of primary coil 2b Termination of primary coil 3 Secondary coil 4 Iron core 5 Igniter 5a, 5b, 5c, 5d, 5e Terminal of igniter 6 Module accommodation room 7 Primary connector 71, 72, 73, 74 External connection terminal 71 m, 72 m, 73 m, 74 m Case side end 10 Ignition coil for internal combustion engine 11 Secondary connector 12 High voltage terminal 16 Insulating resin 17 Buffer material

Continued on the front page (72) Inventor Rei Takada 2-1-26-Todori, Nada-ku, Kobe-shi, Hyogo F-term in Hanshin Electric Co., Ltd. (reference) 3G019 KC05 KC06 KC08 KD07

Claims (3)

[Claims] 1. An ignition coil for an internal combustion engine having a module housing chamber for housing a primary coil, a secondary coil, and a switching module in an insulating case and having a primary connector on a peripheral wall of the insulating case, wherein the ignition coil is provided on the primary connector. An internal connection, wherein the intervals between the terminals of the external connection terminals on the insulating case side, the terminals at the start and end of the primary coil, and the intervals between the terminals of the switching module are the same or substantially the same. Engine ignition coil. 2. The ignition coil for an internal combustion engine according to claim 1, wherein an aspect ratio of the switching module in a front view is about 1.5 to 1.9: 1. 3. An ignition coil for an internal combustion engine having a module housing chamber for housing a primary coil, a secondary coil, and a switching module in an insulating case, and having a primary connector on a peripheral wall of the insulating case, wherein the insulating coil is insulated into the insulating case. An ignition coil for an internal combustion engine, wherein a resin is injected and cured, and the module accommodating chamber is filled with a flexible heat-resistant and flexible cushioning material.