JPH0587034A - Ignition device for internal combustion engine - Google Patents

Abstract

PURPOSE:To house an ignition coil and an ignitor densely in a single case without hampering a heat radiation, and to improve the installing property to an internal combustion engine. CONSTITUTION:An ignition coil winding 2 and a mould type ignitor 50 are housed in a case 40, a potting resin 60 is injected and hardened in the case 40, and furthermore, the ignitor 50 is arranged at the opening end side of the case 40, and a heat sink 55 is assembled to the ignitor 50 exposing from the potting resin 60.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to an ignition device for an internal combustion engine which is directly mounted on the internal combustion engine.

[0002]

2. Description of the Related Art As a conventional device of this type, there is considered a device in which an igniter is externally integrated with an opening end of a case for accommodating an ignition coil winding portion (for example, Japanese Patent Laid-Open No. 63-120863). Publication).

[0003]

However, in the above-mentioned conventional one, since the igniter is externally attached to the case of the ignition coil, in consideration of the mounting on the internal combustion engine, which tends to be downsized recently, Still not enough.

Therefore, an object of the present invention is to improve the mountability to an internal combustion engine without impairing the heat dissipation.

[0005]

Therefore, according to the present invention, there is provided a case having an opening end, an ignition coil winding portion housed in the case, and an opening end side of the ignition coil disposed inside the case. An igniter that interrupts the next current, a potting resin that is injected and hardened in the case and encloses the ignition coil winding portion and the igniter, and is exposed from the potting resin on the opening end side of the case and is assembled to the igniter. An ignition device for an internal combustion engine including a heat sink attached thereto.

[0006]

As a result, the ignition coil winding portion and the igniter are housed in the case and sealed by the potting resin, and are generated in the igniter by the heat sink that is exposed from the potting resin and attached to the igniter at the opening end side of the case. Heat is dissipated in the air.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 6, an ignition coil winding portion 2 including a primary coil 10 and a secondary coil 20, and a secondary coil 20.
Of the primary coil 10 so that a high voltage is generated in the secondary coil 20 in accordance with the operating state of the internal combustion engine.
The mold type igniter 50 for connecting and disconnecting the next current is housed in the same resin case 40, and the potting resin 60 is injected and cured in the case 40 to be formed.

In the mold type igniter 50, a portion embedded in the potting resin 60 is overcoded with a thermoplastic elastomer 53 in order to prevent cold stress. A heat sink 55 is attached to the mold type igniter 50 to promote heat dissipation of a power transistor (not shown), which is a component of the mold type igniter 50. The heat sink 55 has its upper end surface exposed from the potting resin 60. Is disposed in the opening at the upper end of the case 40. The connector 30 for external connection is arranged and fixed on the upper side surface of the case 40, and the mold type igniter 50 and the ignition coil winding portion 2 are connected to each other by connecting the ignition coil winding portion 2 to the lower terminal 31 of the connector 30. Then
Each L formed by projecting from the igniter 50 on each upper terminal 32
By connecting the character-shaped terminals 51, the terminals 31 and 32 of the connector 30 are electrically connected.

A heat sink 55 made of a U-shaped metal plate
4 to 6 for positioning with the igniter 50.
As shown in FIG. 5, a launching protrusion 58 is provided to enter the hole 52 formed in the igniter 50, and two positioning protrusions 56 and 57 extending in parallel along the outer periphery of the igniter 50 are provided for positioning with the outer periphery of the igniter 50. Is provided.

When the heat sink 55 having the igniter 50 assembled therein is put in the case 40, a plurality of ribs 42 extending in the vertical direction are integrally formed on the inner peripheral surface of the case 40 as a positioning for the heat sink 55. Has been done.

Also, considering the clearance when assembling the igniter 50 to each upper terminal 32 of the connector 30,
As shown in FIG. 3, each elongated hole 35 is opened so that each L-shaped terminal 51 of the igniter 50 can be easily inserted.

In the above structure, when the power transistor of the mold type igniter 50 is turned off, the current flowing through the primary coil 10 is cut off, so that a high voltage is generated in the secondary coil 20. And this secondary coil 2
The high voltage generated at 0 is directly applied to the head terminal of the spark plug through the spark plug connecting fitting 25, whereby the spark plug generates a spark discharge in the combustion chamber of the internal combustion engine.

Further, the power transistor is turned on and off.
The heat generated in the mold type igniter 50 is radiated into the air via the heat sink 55. As a result, the igniter 50 and the ignition coil winding portion 2 are compactly housed in the same case 40 without impairing the heat dissipation, and the mountability of the ignition device to the internal combustion engine is improved.

In the above embodiment, the mold type igniter 50 was overcoated with the thermoplastic elastomer 53, but in the embodiment of FIG.
0, and the coil potting resin 60 is injected and cured to the upper part of the ignition coil winding part 2 in the case 40, and then the mold type igniter 50 is housed in the case 40 and connected to the upper terminal 32 of the connector 30. And case 4
Around the portion of the mold type igniter 50 in 0, a soft resin 70 for preventing thermal stress is injected and cured. 2
It consists of round potting.

Further, in the above-described embodiment, the igniter 50 and the ignition coil winding portion 2 are connected via the connection terminals 31 and 32 of the external connection connector 30. The igniter 50 may be directly connected by a connection terminal different from the external connection connector 30.

Further, in the above-mentioned embodiment, the present invention is applied to the case 40 in which the ignition plug connecting terminal 25 is provided and directly connected to the ignition plug, and the ignition device is directly attached to the internal combustion engine. However, the present invention can also be applied to the one in which the ignition coil winding portion 2 is connected to the spark plug via the ignition cable.

[0017]

As described above, according to the present invention, the ignition coil winding portion and the igniter are housed in the case and sealed with the potting resin, and exposed to the igniter from the potting resin on the opening end side of the case. The heat generated in the igniter is dissipated in the air by the assembled heat sink, so that the ignition coil winding part and the igniter can be compactly housed in the same case without impairing the heat dissipation. There is an excellent effect that the mountability to the engine can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the device of the present invention.

FIG. 2 is a plan view showing an embodiment of the device of the present invention.

FIG. 3 is a plan view showing a state before the potting resin is injected in the above embodiment.

FIG. 4 is a perspective view showing an assembled state of the igniter and the heat sink in the above embodiment.

FIG. 5 is a perspective view showing a heat sink in the above embodiment.

FIG. 6 is a perspective view showing an igniter in the above embodiment.

FIG. 7 is a vertical sectional view showing another embodiment of the device of the present invention.

[Explanation of symbols]

 2 Ignition coil winding part 10 Primary coil 20 Secondary coil 30 Connector for external connection 31 Lower terminal 32 Upper terminal 40 Case 50 Igniter 53 Thermoplastic elastomer 55 Heat sink

Claims (4)

[Claims] 1. A case having an open end, an ignition coil winding part housed in the case, an igniter arranged on the open end side in the case and connecting and disconnecting a primary current of the ignition coil, For an internal combustion engine including a potting resin that is injected and hardened in a case and that encloses the ignition coil winding portion and the igniter, and a heat sink that is exposed from the potting resin on the opening end side of the case and is attached to the igniter Ignition device. 2. The ignition device for an internal combustion engine according to claim 1, wherein a portion of the igniter embedded in the potting resin is overcoated with a thermoplastic elastomer. 3. A connector for external connection is fixed to an upper part of the case, and the connector is provided with terminals respectively connected to the ignition coil winding portion and the igniter, and the ignition is performed through the terminals. The ignition device for an internal combustion engine according to claim 1, wherein the coil winding portion and the igniter are electrically connected. 4. The ignition device for an internal combustion engine according to claim 1, wherein the case is provided with a spark plug connection terminal, and the spark plug is directly connected to the spark plug connection terminal.