Internal-combustion-engine ignition coil apparatus

1. An internal-combustion-engine ignition coil apparatus that supplies an ignition plug mounted in an internal combustion engine with a voltage for producing a spark discharge, the internal-combustion-engine ignition coil apparatus comprising:

a primary coil;

a secondary coil disposed in such a way as to surround an outer circumferential portion of the primary coil;

an iron core that makes the primary coil and the secondary coil magnetically couple with each other;

a case that contains the primary coil, the secondary coil, and the iron core;

a connector assembly in which a connector and an igniter are integrally fixed to each other; and

a heat sink that cools the igniter,

wherein the connector assembly is assembled to the case,

wherein the igniter is contained in the case,

wherein the case has an opening window that opens in a wall face portion thereof facing a surface portion of the igniter,

wherein the heat sink is inserted into the case through the opening window and is bonded not only to the surface portion of the igniter with a first adhesive but also to the inner circumferential surface of the opening window with a second adhesive, and the heat sink has an exposed portion that is exposed to the outside of the case through the opening window, and

wherein a potting resin is filled into the case.

2. The internal-combustion-engine ignition coil apparatus according to claim 1 , wherein the first adhesive and the second adhesive are made of respective adhesives different from each other.

3. The internal-combustion-engine ignition coil apparatus according to claim 2 , wherein the first adhesive is made of an adhesive having heat radiation performance higher than that of the second adhesive.

4. The internal-combustion-engine ignition coil apparatus according to claim 3 ,

wherein the connector assembly has a connector end portion that protrudes from a side-surface portion of the connector,

wherein the case has a connector mounting portion in the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

5. The internal-combustion-engine ignition coil apparatus according to claim 3 ,

wherein the connector assembly has a connector end portion in the a front-end portion of the connector,

wherein the case has a connector mounting portion in a wall face portion thereof perpendicular to the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

6. The internal-combustion-engine ignition coil apparatus according to claim 2 ,

wherein the connector assembly has a connector end portion that protrudes from a side-surface portion of the connector,

wherein the case has a connector mounting portion in the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

7. The internal-combustion-engine ignition coil apparatus according to claim 2 ,

wherein the connector assembly has a connector end portion in a front-end portion of the connector,

wherein the case has a connector mounting portion in a wall face portion thereof perpendicular to the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

8. The internal-combustion-engine ignition coil apparatus according to claim 1 , wherein the first adhesive and the second adhesive are made of one and the same adhesive.

9. The internal-combustion-engine ignition coil apparatus according to claim 8 ,

wherein the connector assembly has a connector end portion that protrudes from a side-surface portion of the connector,

wherein the case has a connector mounting portion in the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

10. The internal-combustion-engine ignition coil apparatus according to claim 8 ,

wherein the connector assembly has a connector end portion in the a front-end portion of the connector,

wherein the case has a connector mounting portion in a wall face portion thereof perpendicular to the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

11. The internal-combustion-engine ignition coil apparatus according claim 1 , wherein the case has a recessed groove in a peripheral portion of the opening window.

12. The internal-combustion-engine ignition coil apparatus according to claim 11 ,

wherein the heat sink has a flange portion provided in a peripheral portion thereof and a protruding portion having a surface portion that protrudes in a direction perpendicular to a surface portion of the flange portion,

wherein the protruding portion is inserted into the case through the opening window,

wherein the surface portion of the protruding portion is bonded to the surface portion of the igniter with the first adhesive,

wherein a wall face portion of the protruding portion is bonded to the inner circumferential surface of the opening window with the second adhesive, and

wherein the flange portion is bonded to the case with the second adhesive filled into the recessed groove and is exposed to the outside of the case.

13. The internal-combustion-engine ignition coil apparatus according to claim 12 ,

wherein the connector assembly has a connector end portion that protrudes from a side-surface portion of the connector,

wherein the case has a connector mounting portion in the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

14. The internal-combustion-engine ignition coil apparatus according to claim 11 ,

wherein the connector assembly has a connector end portion that protrudes from a side-surface portion of the connector,

wherein the case has a connector mounting portion in the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

15. The internal-combustion-engine ignition coil apparatus according to claim 11 ,

wherein the connector assembly has a connector end portion in the a front-end portion of the connector,

wherein the case has a connector mounting portion in a wall face portion thereof perpendicular to the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

16. The internal-combustion-engine ignition coil apparatus according to claim 1 ,

wherein the connector assembly has a connector end portion that protrudes from a side-surface portion of the connector,

wherein the case has a connector mounting portion in the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.

17. The internal-combustion-engine ignition coil apparatus according to claim 16 , wherein an endface of the connector end portion, the surface portion of the igniter facing to the opening window, and the surface of the case, in which the opening window is provided, are formed in such a way as to extend in one and the same direction.

18. The internal-combustion-engine ignition coil apparatus according to claim 17 , further comprising a fin provided on the exposed portion of the heat sink, wherein the fin is formed in such a way that a first dimension, of the fin from the wall face portion of the case to a front-end portion of the fin, is smaller than a second dimension, from the wall face portion of the case to the side-surface portion, of the connector.

19. The internal-combustion-engine ignition coil apparatus according to claim 16 , further comprising a fin provided on the exposed portion of the heat sink, wherein the fin is formed in such a way that a first dimension, of the fin from the wall face portion of the case to a front-end portion of the fin, is smaller than a second dimension, from the wall face portion of the case to the side-surface portion;

at the anti case side, of the connector.

20. The internal-combustion-engine ignition coil apparatus according to claim 1 ,

wherein the connector assembly has a connector end portion in the a front-end portion of the connector,

wherein the case has a connector mounting portion in a wall face portion thereof perpendicular to the wall face portion having the opening window, and

wherein the connector end portion is coupled with the connector mounting portion so that the connector assembly is assembled to the case.