JP4161784B2 - Ignition device for internal combustion engine - Google Patents

Description

[0001]
【Technical field】
The present invention relates to an ignition device for an internal combustion engine having an ignition plug that performs an ignition operation in a combustion chamber of the internal combustion engine and an ignition coil that energizes the ignition plug.
[0002]
[Prior art]
As shown in FIGS. 1 and 2, which will be described later, the plug hole provided in the cylinder head of the internal combustion engine has a spark plug attached to the bottom surface, and the spark plug is electrically connected to the ignition coil inserted into the plug hole and the plug hole. Connected.
The plug hole has an opening that opens to the outside of the cylinder head. The opening is closed by a coil flange provided below the coil head, and the coil flange and the plug hole are opened so that dust and water do not enter. A disc-shaped seal plate is provided between the outer peripheral surface of the cylinder head and the plug hole is closed.
[0003]
However, the gas in the plug hole may be heated and expanded due to combustion in the combustion chamber of the internal combustion engine or heat generated when the ignition coil is operated, and there is a problem with complete sealing of the plug hole.
Furthermore, since energization between the ignition coil and the spark plug is often performed by a high-voltage current, ozone may be generated and ventilation in the plug hole may be necessary.
Therefore, a gas passage is generally provided between the seal plate and the coil flange portion so that gas can be exchanged between the inside of the plug hole and the outside of the cylinder head.
[0004]
As a specific example of the gas passage, a conventionally known configuration is shown in FIGS.
As shown in FIGS. 7 and 8, a circumferential groove 90 is provided on the upper surface 105 of the seal plate 9 facing the coil flange portion side so that the coil flange portion and the seal plate 9 are brought into close contact with each other. Thereby, the circumferential groove part 90 can be utilized as a gas passage.
That is, as shown in FIGS. 7 and 8, the circumferential groove portion 90 includes a plurality of water reservoir portions 91 provided on the upper surface 105 of the annular seal plate 9 and a connecting groove 92 that connects the water reservoir portions 91.
The depth of the water reservoir 91 is deeper than the connecting groove 92, an internal passage 122 communicating with the inside of the plug hole on the inner peripheral side of a certain connecting groove 92, and a cylinder on the outer peripheral side of another connecting groove 92 not provided with the internal passage 122. An external passage 121 leading to the outside of the head is provided.
The seal plate 9 according to this configuration is brought into close contact with the coil flange portion to form a gas passage.
[0005]
The gas inside the plug hole enters the connection groove 92 provided with the external passage 121 through the internal passage 122, the connection groove 92 provided with the internal passage 122, and the water reservoir 91 adjacent to the connection groove 92. It can pass out of the cylinder head through the passage 121.
When water enters the gas passage due to water from the outside of the cylinder head, the water is stored in the water storage groove 91 deeper than the connection groove 92 and the momentum is suppressed, and it is difficult to reach the inside of the plug hole.
[0006]
[Patent Document 1]
Japanese Patent No. 03145880 Publication
[Problems to be solved]
However, since the coil flange portion and the seal plate are not completely in close contact with each other, water may enter through the gap between the two.
In this case, both the water that has entered from the gap between the coil flange portion and the seal plate and the water that has entered from the external passage 121 via the connecting groove 92 and the like accumulate in the water reservoir 91 and overflow from the water reservoir 91. Water may enter the plug hole through the inner passage 122.
[0008]
The present invention has been made in view of such conventional problems, and an object of the present invention is to provide an ignition device for an internal combustion engine in which water does not easily enter a plug hole.
[0009]
[Means for solving problems]
A first aspect of the present invention is an ignition for an internal combustion engine having an ignition coil that is inserted through the opening into a plug hole having an opening that is attached to the bottom of the cylinder head and has an opening that opens to the outside of the cylinder head. A device,
The ignition coil, a coil flange for closing the opening and having a coil cylindrical portion to be inserted into the opening of the plug hole, and between the periphery of the lower surface and the opening of the coil flange it is interposed an annular seal plate,
The seal plate is an annular member having an insertion hole through which the coil cylindrical portion is inserted at the center, and the gap between the inner peripheral surface forming the insertion hole and the outer peripheral surface facing the outside of the cylinder head is A gas passage that enables gas exchange between the inside of the plug hole and the outside of the cylinder head;
The gas passage is made through passage which penetrates between the inner peripheral surface and the outer circumferential surface, also e Bei an inner opening and the outer opening which opens respectively and the inner peripheral surface and the outer peripheral surface,
Inside of the through passage, there be provided a water reservoir configured to larger diameter than the upper Symbol in opening and external opening in an internal combustion engine ignition device according to claim (Claim 1).
[0010]
Next, the effects of the present invention will be described.
In the ignition device for an internal combustion engine according to the present invention, the gas passage that enables gas exchange between the plug hole and the outside of the cylinder head is a through passage that penetrates the seal plate.
This through passage does not have a portion communicating with the outside of the seal plate at a portion other than the internal opening and the external opening. For this reason, when the cylinder head is exposed to water from the outside, the water only enters the external opening, and the amount of water entering can be reduced to prevent water from reaching the internal opening.
Furthermore, a water reservoir is formed by providing a large-diameter portion inside the through passage. When water enters from the external opening, water can be received at the water reservoir so that no further water can enter.
[0011]
As described above, according to the present invention, it is possible to provide an internal combustion engine ignition device in which water does not easily enter the plug hole.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
In the sealing plate according to the present invention, the diameters of the external opening and the internal opening are larger in the external opening (see FIG. 3) and larger in the internal opening (see FIG. 5). Either form can be selected.
If water accumulates in the vicinity of the external opening due to flooding, the external opening may be blocked by water, making it difficult to exchange gas between the outside of the cylinder head and the inside of the plug hole. If the external opening is large, the risk of water blocking the external opening can be reduced.
When the internal opening is large, more gas can be discharged from the plug hole to the outside of the cylinder head, and the risk of water intrusion due to flooding can be reduced.
In view of such characteristics, the size of the diameter of the external opening and the internal opening can be selected as appropriate according to the use environment.
[0013]
Further, a plurality of gas passages composed of through passages can be provided. In this case, gas exchange between the outside of the cylinder head and the inside of the plug hole can be promoted. Furthermore, when water enters the through-passage from the external opening due to flooding, the area through which gas can pass through the through-passage is reduced, and gas exchange may be difficult. By providing a plurality of gas passages, gas exchange between the outside of the cylinder head and the inside of the plug hole can be reliably performed.
[0014]
Further, the through-passage is provided with a rising slope towards the inner peripheral surface from the outer peripheral surface, the inner opening is preferably in the higher position relative to the opening of the flop Raguhoru than the external opening (Claim 2).
When water enters from the external opening, it is necessary to climb the ascending slope of the through passage, so that it becomes more difficult for water to enter.
[0015]
Further, the central locus of the width of the figure projected on the plane perpendicular to the axial center of the plug hole has a shape passing through a point deviated from one straight line passing through the center of the seal plate. (Claim 3).
As shown in FIG. 6 to be described later, the through-passage having such a central locus is long, so that it is difficult for water to reach the internal opening.
[0016]
The internal combustion engine ignition device according to the present invention is preferably used for engines of various vehicles and automobiles.
This is because various vehicles, automobiles, and the like often need to have a mechanism for preventing water and water vapor from entering the plug hole as described in the present invention because the cylinder head is exposed to water by car washing or rain.
[0017]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
(Example 1)
As shown in FIGS. 1 to 4, the internal combustion engine ignition apparatus 200 according to the present example has the above-described opening portion with respect to the plug hole 20 having the opening portion 21 that is attached to the bottom portion 25 and opened to the outside of the cylinder head 2. 21 is an internal combustion engine ignition device 200 having an ignition coil 3 that is inserted from 21 and electrically connected to an ignition plug 35.
[0018]
As shown in FIGS. 1 and 2, the ignition coil 3 has a coil flange portion 4 that closes the opening 21 of the plug hole 20, and a lower surface 41 of the coil flange portion 4 and an opening periphery 210. An annular seal plate 1 is interposed therebetween. The seal plate 1 has a gas passage that allows gas exchange between the inside of the plug hole 20 and the outside of the cylinder head 2.
[0019]
As shown in FIGS. 2 and 3 , the gas passage is provided through the inside of the seal plate 1 and opens to an inner peripheral surface and an outer peripheral surface 192 formed by the inclined surface 191 of the seal plate 1. and a opening 152 and the outer opening portion 151, a through passage 150 you through I transected between the inner peripheral surface and the outer circumferential surface 192 in the radial direction. Further, a water reservoir 153 having a diameter larger than that of the two internal openings 152 and the external opening 151 is provided inside the through passage 150.
[0020]
As shown in FIGS. 2 and 3, the through passage 150 has a rising slope from the outer peripheral surface 192 toward the inner peripheral surface, and the inner opening 152 is more external to the cylinder head 2 than the outer opening 151. It is in a higher position with respect to the opening 21 of the plug hole 20.
[0021]
This will be described in detail below.
As shown in FIGS. 1 and 2, in an internal combustion engine ignition device 200 used in an automobile engine, a spark plug 35 is provided at the bottom 25 of a cylindrical plug hole 20 provided in the cylinder head 2, and an ignition part is provided outside the plug hole 20. It is attached to be exposed in the engine.
The opening 21 that opens to the outside of the cylinder head 2, as the coil head 31 of larger diameter than the opening 21 to expose the ignition coil 3 is inserted into the plug hole 20, the coil cylindrical portion of the ignition coil 3 A plug head portion 351 of the spark plug 35 is inserted into a cylindrical mounting portion 322 provided at the tip of 32. The plug head 351 comes into contact with the coil 321 inside the mounting portion 322, and the ignition plug 35 and the ignition coil 3 are electrically connected here.
[0022]
An insulating plug cap 33 is provided so as to cover the outer periphery of the mounting portion 322 and the plug head 351 so as to ensure insulation between the mounting portion 322, the plug head 351, and the inner wall surface 251 of the plug hole 20. .
A coil flange portion 4 having a diameter larger than that of the opening 21 is provided below the coil head 31 in the ignition coil 3, and the seal plate 1 is interposed between the coil flange portion 4 and the opening peripheral edge 210 of the cylinder head 2. Disguise.
[0023]
As shown in FIGS. 2 to 4, the seal plate 1 is an annular member having an insertion hole 190 through which the coil cylindrical portion 32 of the ignition coil 3 is inserted at the center. The periphery of the insertion hole 190 includes an inclined surface 191 that is inclined toward the insertion hole 190. In the configuration according to this example, the inner peripheral surface where the internal opening 152 is opened becomes the inclined surface 191.
In the seal plate 1 , the lower surface 103 facing the opening 21 that opens to the outside of the cylinder head 2 has an annular leg 104 that protrudes toward the periphery of the opening 210 and is formed along the circumferential direction of the annular seal plate 1. The tip of the annular leg 104 and the opening periphery 210 come into contact with each other, whereby the seal plate 1 and the cylinder head 2 are sealed.
The seal plate 1 is made of a heat-resistant elastic insulating resin such as samprene, EPDM, acrylic resin, silicone rubber, or fluorine resin, or a heat-resistant rubber disk.
[0024]
The gas passage of the seal plate 1 will be described.
As shown in FIGS. 3 and 4, the seal plate 1 of this example has two gas passages. This gas passage is in a symmetric position in the radial direction across the center position G of the seal plate 1.
From the outer opening 151 toward the inner opening 152, the outer opening 151 and the vicinity become an outer portion 155 configured to have the same diameter for a while, and an enlarged portion 156 that gradually increases from the middle toward the inside. . In the vicinity of the center, the diameter is larger than that of the external opening 151 and the internal opening 152 to form a water reservoir 153, and the inner side of the diameter switching unit 154 is an inner part 157 having the same diameter as the internal opening 152.
As shown in FIG. 4, the through passage 150 has a rising slope from the outside toward the inside. That is, the trajectory connecting the center positions in the respective cross sections of the through-passage 150 is arranged on a straight line, and the outer opening 151 side is the lowest and the inner opening 152 side is the highest with the opening 21 of the cylinder head 2 as a reference.
The outer opening 151 is larger in diameter than the inner opening 152.
[0025]
Next, the function and effect according to this example will be described.
In the ignition device 200 for the internal combustion engine of the present example, the gas passage that enables gas exchange between the plug hole 20 and the outside of the cylinder head 2 includes two through passages 150 provided inside the seal plate 1.
As a result, when the cylinder head 2 is exposed to water from the outside, the water intrusion path is only the external opening 151, and the amount of water intrusion when the water is immersed is reduced to prevent water from reaching the internal opening 152. it can.
[0026]
Furthermore, this can be used as the water reservoir 153 by providing a large-diameter portion inside the through passage 150. When water enters from the external opening 151, the water reservoir 153 receives water, and the end of the water reservoir 153 is configured as a switching unit 154 whose diameter is switched from large to small. It is possible to prevent water from getting into the interior (because it only has the internal opening 152).
[0027]
Further, the through passage 150 has a rising slope from the external opening 151 toward the internal opening 152, and the internal opening 152 is located at a higher position in the external opening 151 and the internal opening 152 as shown in FIG. is there. Therefore, even if water enters from the external opening 151, the water cannot reach the inner opening 152 at the back up the slope.
In addition, water may accumulate near the external opening 151 due to flooding, and the external opening 151 may be blocked, making it difficult to exchange gas between the outside of the cylinder head 2 and the inside of the plug hole 20. In this example, since the outer opening 151 is larger in diameter than the inner opening 152, the risk of blocking the outer opening 151 due to water can be reduced.
[0028]
Further, in this example, two gas passages including the through passage 150 are provided, and gas exchange between the outside of the cylinder head 2 and the inside of the plug hole 20 can be actively performed. Furthermore, the water may enter and accumulate in the through-passage 150 from the external opening 151 due to flooding, so that the area through which the gas can pass in the through-passage 150 is reduced, and gas exchange may be difficult. is there. By providing two, gas exchange between the outside of the cylinder head 2 and the inside of the plug hole 20 can be performed more reliably.
[0029]
As described above, according to this example, it is possible to provide an ignition device for an internal combustion engine in which water does not easily enter the plug hole.
[0030]
(Example 2)
As shown in FIG. 5, the seal plate 1 according to this example is a seal plate 1 having a gas passage including a through passage 150 according to the same configuration provided in the ignition device for an internal combustion engine according to the same configuration as the first embodiment. is there.
However, it has a shape opposite to that of the through passage 150 of the first embodiment.
That is, the outer opening 151 has a small diameter, the inner opening 152 has a larger diameter, and the outer opening 151 is configured to have the same diameter for a while from the outer opening 151 toward the inner opening 152. The diameter is changed by the outer part 161 and the diameter switching part 162 and the diameter is larger than those of the external opening 151 and the internal opening 152, thereby forming the water reservoir 153. Thereafter, a reduction unit 163 that gradually reduces as the diameter goes inward is continued. Further, an inner portion 164 having the same diameter as the inner opening 152 continues to reach the inner opening 152.
[0031]
Although not shown, the through passage 150 has an upward slope from the outside to the inside. That is, the trajectory connecting the center positions of the cross sections of the through-passage 150 is arranged on a straight line, and the outer opening 151 side is the lowest and the inner opening 152 side is the highest with respect to the opening of the cylinder head.
The rest of the configuration is the same as that of the first embodiment.
[0032]
In addition, you may provide the highest location between the internal opening part 152 and the external opening part 151. FIG. In this case, there is an advantage that the inclination of the gas passage can be set to the maximum with respect to the limited space in the thickness direction of the seal plate 1 and it is difficult for moisture to enter.
[0033]
According to the seal plate 1 of this example, the inner opening 152 is larger in diameter than the outer opening 151, and more gas can be discharged from the plug hole to the outside of the cylinder head. Furthermore, the risk of water intrusion due to flooding can be reduced.
Other functions and effects are the same as those of the first embodiment.
[0034]
(Example 3)
The seal plate 1 according to this example is a seal plate 1 having a gas passage including two through passages 150 according to the same configuration provided in the internal combustion engine ignition device according to the same configuration as the first embodiment.
As shown in FIG. 6, the straight lines K1 and K2 are a center locus of the width of the figure projected on the plane perpendicular to the axis of the plug hole and a line obtained by extending the center locus. The straight lines K1 and K2 do not pass through the center G of the disc-shaped seal plate 1.
The through passage 150 includes an internal opening 152 that opens to the inner peripheral surface of the inclined surface 191 and an external opening 151 that opens to the outer peripheral surface 192.
The rest of the configuration is the same as that of the first embodiment.
[0035]
According to the seal plate 1 of this example, the length of the through passage 150 can be made longer than that of the through passage 150 of the first and second embodiments provided along a straight line passing through the center G.
That is, as shown in FIG. 6, the length of the through passage 150 according to this example is equal to the distance W <b> 1 connecting the center of the external opening 151 and the internal opening 152. The distance between the inclined surface 191 that is the inner peripheral surface along the radial straight line K0 passing through the center G and the outer peripheral surface 192 is W0, and W0 <W1.
When the through-passage 150 is long, the water that has entered from the external opening 151 reaches the internal opening 152 through a longer path, so that the water enters the plug hole by being exposed to water outside the cylinder head. It becomes more difficult.
Other functions and effects are the same as those of the first embodiment.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an entire internal combustion engine ignition device in Embodiment 1. FIG.
FIG. 2 is an explanatory diagram showing a close contact state between a coil flange portion and a seal plate in the first embodiment.
FIG. 3 is a plan view of a seal plate according to the first embodiment.
4 is a cross-sectional view of the seal plate taken along the line AA in FIG. 3 according to the first embodiment.
FIG. 5 is a plan view of a seal plate having a through passage having a smaller outer opening and a larger inner opening in the second embodiment.
6 is a plan view of a seal plate having a through path provided at a position deviating from the radial direction passing through the center of the seal plate in Embodiment 3. FIG.
FIG. 7 is a plan view of a conventional seal plate.
FIG. 8 is a cross-sectional view of a conventional seal plate taken along the line BB.
[Explanation of symbols]
1. . . Sealing plate,
100. . . Bottom,
105. . . Top surface,
150. . . Throughway,
151. . . External opening,
152. . . Internal opening,
153. . . Water reservoir,
192. . . Outer peripheral surface,
2. . . cylinder head,
200. . . Ignition device for internal combustion engine,
21. . . Aperture,
210. . . Opening periphery,
25. . . bottom,
3. . . Ignition coil,
35. . . Spark plug,
4). . . Coil flange,
41. . . Underside,

Claims (3)

An ignition device for an internal combustion engine having an ignition coil that is inserted through the opening into a plug hole having an opening that opens to the outside of a cylinder head with an ignition plug attached to the bottom, and is electrically connected to the ignition plug,
The ignition coil, a coil flange for closing the opening and having a coil cylindrical portion to be inserted into the opening of the plug hole, and between the periphery of the lower surface and the opening of the coil flange it is interposed an annular seal plate,
The seal plate is an annular member having an insertion hole through which the coil cylindrical portion is inserted at the center, and the gap between the inner peripheral surface forming the insertion hole and the outer peripheral surface facing the outside of the cylinder head is A gas passage that enables gas exchange between the inside of the plug hole and the outside of the cylinder head;
The gas passage is made through passage which penetrates between the inner peripheral surface and the outer circumferential surface, also e Bei an inner opening and the outer opening which opens respectively and the inner peripheral surface and the outer peripheral surface,
Further, the inside of the through-passage, the upper Symbol in opening and external opening ignition device for an internal combustion engine characterized by comprising providing a water reservoir configured to larger diameter than. According to claim 1, said through-passage is provided with a rising slope towards the inner peripheral surface from the outer peripheral surface, the inner opening is in the higher position relative to the opening of the flop Raguhoru than the external opening An internal combustion engine ignition device.   3. The center locus of the width of a figure obtained by projecting the through path onto a plane perpendicular to the axis of the plug hole is a point deviated from one straight line passing through the center of the seal plate. An internal combustion engine ignition device characterized by having a passing shape.

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