JP2003328918A - Ignition device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ignition device for an internal combustion engine wherein a work to mount and demount an ignition coil is facilitated. <P>SOLUTION: A design cover 4 presses and energizes a head part 3a of an ignition coil 3 contained in a coil containing part 2a of an engine head cover 2. Thus, during mounting and demounting of the ignition coil 3, a work to fasten or loosen a screw is not needed, and a remarkable improvement of the efficiency of a work to mount and demount the ignition coil 3 is effected. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an internal combustion engine ignition device used in an internal combustion engine of an automobile or the like.

[0002]

2. Description of the Related Art Conventionally, as in an ignition device 51 for an internal combustion engine shown in FIG. 9, a stick type ignition coil 53 is provided in a coil housing portion 52a formed in an engine head cover 52.
There is a configuration that is equipped with. In such an ignition device 51, the ignition coil 53 is fixed to the engine head cover 52 by fixing the ignition coil 53 to the engine head cover 52 by screwing the flange 54 horizontally protruding from the side surface of the head 53a of the ignition coil 53 with a screw 56. Has become.

Further, a seal rubber 55 is provided on the outer periphery of the ignition coil 53, and the ignition coil 53 is pressed and fixed to the engine head cover 52 by screws, and at the same time, the seal rubber 55 closes the gap between the engine head cover 52 and the engine head. The intrusion of water into the plug hole 22 of 21 is prevented. A labyrinth-shaped breathing hole 55a is formed in the seal rubber 55, and a small amount of blow-by gas leaking from the combustion chamber 23 into the plug hole 22 is discharged to the outside through the breathing hole 55a. ing.

On the other hand, the head portion 53a of the ignition coil 53 is provided with a connector portion 57 and the connector portion 5 thereof.
7 is connected to a sub-harness 61 with a waterproof connector that is electrically connected to an engine control device (not shown), and an ignition signal or voltage emitted from the engine control device is input to the ignition coil 53. .

[0005]

However, in the above-mentioned conventional ignition device 51, when the ignition coil 53 is attached or detached, it is necessary to fasten or loosen the screw 56, and in particular, a large number of ignitions like a multi-cylinder internal combustion engine. When the coil 53 is mounted, there is a problem that many screws 56 need to be fastened or loosened, which requires a lot of working time.

[0006] Further, since it has a structure in which a sub-harness for connecting each component such as the sub-harness 61 with a waterproof connector is laid in the engine room, it is difficult to make the engine compact and lightweight. There was a problem that it looked bad.

The present invention provides an ignition device for an internal combustion engine in which the work of attaching and detaching the ignition coil can be easily performed, and further, the wire harness is integrated with the head cover to form a head cover corresponding to the wire harness. The problem to be solved is to reduce the crawling of the sub harness for appearance, to make it look good, and to make it advantageous for weight reduction and cost reduction.

[0008]

In order to achieve this object, an ignition device for an internal combustion engine according to claim 1 is provided with a concave coil accommodating portion on the upper surface and an engine head on the bottom surface of the coil accommodating portion. A coil insertion hole is formed so as to communicate with the plug hole, and an engine head cover attached so as to cover the engine head upper portion, a plug hole and a tubular portion that is inserted into the coil insertion hole that communicates with the plug hole, An ignition coil, which is provided at the upper end of the tubular portion and has a diameter larger than that of the tubular portion, is mounted on the engine head cover in a state of being housed in the coil housing portion, and is housed in the coil housing portion. And a design cover that presses and urges the head of the ignition coil.

Therefore, the engine head cover is provided with a concave coil housing portion on the upper surface thereof, and a coil insertion hole is formed on the bottom surface of the coil housing portion so as to communicate with the plug hole of the engine head to cover the engine head upper portion. The ignition coil has a cylindrical portion that is inserted into the plug hole and the coil insertion hole that communicates with the plug hole, and a head portion that is provided at the upper end of the cylindrical portion and has a diameter larger than that of the cylindrical portion. The engine cover is mounted on the engine head cover in a state of being housed in the coil housing part, and the design cover presses and urges the head of the ignition coil housed in the coil housing part.

Therefore, since the design cover presses and urges the head of the ignition coil, it is not necessary to fix the ignition coil with a screw, and the screw is fastened or loosened when the ignition coil is attached or detached. This eliminates the need for work and greatly improves the efficiency of the work of attaching and removing the ignition coil.

The ignition device for an internal combustion engine according to a second aspect of the invention is characterized in that a vibration damping member is provided on at least a portion of the lower surface of the design cover that abuts the head portion of the ignition coil.

Thus, the vibration damping member strongly presses and urges the ignition coil, and the head of the ignition coil is elastically pressed to prevent vibration of the ignition coil.

Further, in the ignition device for an internal combustion engine according to a third aspect of the present invention, at least a part of the connection terminals electrically connected to the engine control device is provided in the engine head cover to the inner peripheral surface of the coil housing portion. It is characterized in that it is provided so as to be exposed, and a connected terminal is provided on the outer periphery of the head of the ignition coil so as to come into contact with the connection terminal when the head is housed in the coil housing.

Therefore, when the ignition coil head is housed in the coil housing portion, at least a part of the connection terminal is exposed on the inner surface of the coil housing portion and the connected terminal is formed on the outer circumference of the head portion of the ignition coil. When and are brought into contact with each other, they are electrically connected to each other, and the ignition signal and voltage from the engine control device are supplied to the ignition coil.

Therefore, the electrical connection can be easily achieved only by mounting the ignition coil on the engine head cover. Further, since it is not necessary to crawl the connecting sub-harness and the like in the engine room, the engine room can be made compact and lightweight, the cost can be reduced, and the appearance can be improved.

The ignition device for an internal combustion engine according to claim 4 further comprises a packing provided around the coil housing portion, and a seal member provided on the outer periphery under the ignition coil head. The engine head cover is formed with a breathing hole that allows the coil insertion hole to communicate with an external space in a room separate from the coil housing portion.

Therefore, even if a slight amount of blow-by gas in the plug hole leaks from the combustion chamber of the engine, it is reliably discharged into the atmosphere of the external space through the breathing hole, and the electrically connected connection terminal is directly connected. You can prevent touching. Further, since the seal member is provided on the outer periphery of the lower side of the ignition coil head, the connecting terminal and the connected terminal do not come into contact with the blow-by gas containing the sulfur content, etc., and the corrosion of these terminals can be prevented. . Further, since the packing is provided around the coil housing, moisture such as rainwater does not enter the coil housing, and the connection terminals and the connected terminals can be prevented from being corroded by moisture from the outside.

Further, in the ignition device for an internal combustion engine according to a fifth aspect of the present invention, the engine head cover is provided, which covers the upper portion of the engine head having the plug hole and has a coil insertion hole communicating with the plug hole. In an ignition device for an internal combustion engine comprising a coil insertion hole and an ignition coil housed in the plug hole, the engine head cover is exposed on an inner peripheral surface of the coil insertion hole and electrically connected to an engine control device. The ignition coil includes a connection terminal to be connected, and the ignition coil includes a connected terminal that abuts the connection terminal when the ignition coil is accommodated in the plug hole.

Therefore, when the ignition coil is housed in the coil insertion hole of the engine head cover and the plug hole of the engine head, the connection terminal exposed on the inner peripheral surface of the coil insertion hole of the engine head cover is provided in the ignition coil. Contact the connected terminal.

Therefore, only by mounting the ignition coil on the engine head cover, electrical connection with the engine control device can be easily achieved. Furthermore, it is not necessary to crawl the connection sub-harness in the engine room,
It is possible to make the engine room compact and lightweight, reduce the cost, and improve the appearance.

Further, in the ignition device for an internal combustion engine according to a sixth aspect, one of the connection terminal and the connected terminal is a film-shaped terminal, and the other plate is pressed against the film-shaped terminal side for pressure contact. It is characterized by comprising a spring-like terminal.

Therefore, when the ignition coil is housed in the coil insertion hole and the plug hole, the leaf spring-like terminal press-contacts the film-like terminal, so that electrical connection can be easily and reliably achieved between both terminals.

Further, in the ignition device for an internal combustion engine according to a seventh aspect of the present invention, the leaf spring-like terminal is formed by bending a lower end portion of a metal plate arranged in a vertical direction so that the lower end portion is wound upward from below. At the same time, a projection is formed on the surface portion that abuts the film-like terminal.

Therefore, when the ignition coil head is moved relatively downward with respect to the engine head cover and is housed, the leaf spring-like terminal smoothly abuts against the film-like terminal without being caught. In addition, since the projections of the leaf spring-like terminals reliably contact the film-like terminals, it is possible to prevent contact failure.

Further, in the ignition device for an internal combustion engine according to claim 8, a plurality of the leaf spring terminals are juxtaposed, and a wall-shaped projection is formed between the adjacent leaf spring terminals. Characterize.

Therefore, since the adjacent leaf spring terminals are partitioned by the wall projections, it is possible to prevent them from coming into contact with each other and short-circuiting.

Further, in the ignition device for an internal combustion engine according to claim 9, a seal member for sealing between the ignition coil and the engine head cover is provided on the side opposite to the plug with respect to the connected terminal. Is characterized by.

Therefore, the seal member seals between the ignition coil and the engine head cover, so that the connected terminals can be prevented from being exposed to water.

Further, in the ignition device for an internal combustion engine according to a tenth aspect, the ignition coil is formed such that the head portion is reduced in diameter downward in a stepwise manner, and the stepwise outer peripheral surface is formed. The connected terminals are respectively provided on a plurality of stepped portions, and the engine head cover has a stepped shape in which an inner peripheral surface of a coil housing portion that houses the ignition coil head is aligned with an outer peripheral surface of the ignition coil head. The connection terminal is provided on each of a plurality of steps that are formed and form the stepped inner peripheral surface, and one of the connection terminal and the connected terminal is the outer peripheral surface of the ignition coil head or the coil housing. Consisting of the film-shaped terminal provided along the inner peripheral surface of the portion,
The other is composed of the leaf spring-like terminal which is urged toward the film-like terminal and pressed against the film-like terminal.

Therefore, when the ignition coil is housed in the coil insertion hole of the engine head cover and the plug hole of the engine head, the connected terminals are respectively provided on a plurality of stepped portions forming the stepwise outer peripheral surface of the ignition coil, The connection terminals provided on each of a plurality of steps forming the stepped inner peripheral surface of the coil housing portion of the engine head cover come into contact with each other. And, of the connection terminal and the connected terminal,
One of them is a film-shaped terminal provided along the outer peripheral surface of the ignition coil head or the inner peripheral surface of the coil housing portion, and the other is a leaf spring-shaped terminal that is urged and pressed against the film-shaped terminal side. Thus, electrical connection can be easily and reliably achieved between both terminals.

Further, the ignition device for an internal combustion engine according to an eleventh aspect is characterized in that the ignition coil is formed in a columnar shape in which the head portion is reduced in diameter downward in a stepwise manner.

Therefore, since the head portion of the ignition coil is formed in a columnar shape whose diameter is reduced stepwise downward, there is no directivity in assembling in the plane orthogonal to the axial direction with respect to the engine head cover. Therefore, the assembly can be performed very easily, and the number of assembling work steps can be reduced.

In the ignition device for an internal combustion engine according to a twelfth aspect, the film-shaped terminal is formed in a closed curve shape along the outer peripheral surface of the ignition coil head or the inner peripheral surface of the coil housing portion. It is characterized by

Therefore, the film-shaped terminal is formed in a closed curve shape along the outer peripheral surface of the ignition coil head or the inner peripheral surface of the coil housing portion, and the terminal portion is formed on the outer peripheral surface of the ignition coil head or the inner peripheral surface of the coil housing portion. Since it is exposed over the entire circumference of the surface, no matter what direction the ignition coil is installed in the coil housing part of the engine head cover, the leaf spring terminal will always come into contact with the film terminal, and both terminals will contact. The electrical connection between them is surely achieved. Therefore, the ignition coil can be attached to the engine head cover very easily, and the number of assembling steps can be reduced.

[0035]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of an internal combustion engine ignition device embodying the present invention will be described below with reference to the drawings.

First, regarding the first embodiment of the present invention,
This will be described with reference to FIGS. 1 to 5.

As shown in FIG. 1 or 2, the internal combustion engine ignition device 1 is composed of an engine head cover 2, four ignition coils 3 corresponding to each cylinder of the engine, and a design cover 4.

The engine head cover 2 is a resin member attached so as to cover the upper part of the engine head 21. A concave coil housing portion 2 a is provided on the upper surface of the engine head cover 2. Further, the coil insertion hole 2b is formed on the bottom surface of the coil housing portion 2a so as to communicate with the plug hole 22 of the engine head 21 that houses the spark plug 24 with the electrode 25 exposed in the combustion chamber 23 of the engine. Are formed. The coil housing portion 2a has a large diameter so as to house the head portion 3a of the ignition coil 3, while the coil insertion hole 2b has a smaller diameter than the coil housing portion 2a and the tubular portion 3b of the ignition coil 3 is. Can be inserted. The coil housing 2a and the coil insertion hole 2b
Constitutes the coil insertion hole.

Further, the coil housing portion 2a is provided on the inner peripheral surface so that a part of the film-like energizing film-like terminal 5 is exposed. The film-like terminal 5 is formed integrally with the engine head cover 2 and has a thickness of several tens μ.
The terminal member is made of a metal film of m and is electrically connected to an engine control device (not shown) to supply an ignition signal and a power source.

Further, as shown in FIG. 2 or 3, the engine head cover 2 is opened at the inner peripheral surface of the coil insertion hole 2b and the upper edge portion 2c of the coil housing portion 2a, respectively, through the coil insertion hole 2b. A breathing hole 2e for communicating the plug hole 22 with the external space in a room separate from the coil housing 2a is formed.

A groove 2d is formed along the circumferential direction on the upper edge portion 2c of the coil housing 2a, and a ring-shaped and flat rubber packing 6 that is pressed by the design cover 4 to close the groove 2d. Is provided. Further, a part of the concave groove 2d is a wide portion 2f so that a slight gap is formed between the concave groove 2d and the packing 6. Therefore, the plug hole 22 includes the coil insertion hole 2b, the breathing hole 2e, and the concave groove 2d.
Through the space between the packing 6 and the wide portion 2f to communicate with the external space and open to the atmosphere. In addition, the coil storage portion 2a
The packing 6 provided on the periphery of the coil is pressed and urged by the design cover 4 to prevent rainwater and the like from entering the coil housing portion 2a, the coil insertion hole 2b, and the plug hole 22.

The ignition coil 3 is a stick-shaped member in which a predetermined electric circuit for generating a high voltage to be supplied to the ignition plug 24 is built in a case formed of an insulating resin or the like. As shown in FIG. 1, FIG. 2 or FIG. 4, the ignition coil 3 has a cylindrical portion 3b inserted into the plug hole 22 and the coil insertion hole 2b communicating with the plug hole 22, and the cylindrical portion 3b.
It is composed of a substantially cubic head portion 3a which is coaxially provided on the upper end of b and has a diameter larger than that of the cylindrical portion 3b. Head 3
A ring-shaped seal rubber 3c is fitted on the outer circumference of the lower side of a, and the head portion 3a is placed on the bottom surface of the coil housing portion 2a via the seal rubber 3c. Further, the tubular portion 3b has a structure in which the lower end thereof is connected to the upper end portion of the spark plug 24.

A terminal portion 7 is provided on one side surface of the ignition coil head 3a.
Is provided. As shown in FIG. 2B, four leaf spring terminals 7a for energization are juxtaposed in the terminal portion 7, and wall-shaped terminal protection projections 7b are formed between the leaf spring terminals 7a. Has been done. Therefore, since the adjacent terminals 7a are respectively partitioned by the terminal protection protrusions 7b, it is possible to prevent them from coming into contact with each other and short-circuiting.
It is also prevented that the leaf spring-shaped terminal 7a is deformed by an external force.

More specifically, as shown in FIG. 5, the leaf spring-shaped terminal 7a is formed by bending the lower end portion of a vertically arranged metal plate so as to wind it from below to above and at the same time as the film-like terminal. A protrusion 7c is formed on the surface portion that abuts the terminal 5. Therefore, when the ignition coil 3 is mounted on the engine head cover 3, the film-shaped terminal 5 can be smoothly moved without being caught by the film-shaped terminal 5.
Can be pressed against. Further, since the projecting projections 7c surely contact the film-like terminals 5, problems such as poor contact do not occur. 5A is a side view showing a state immediately before the ignition coil 3 is attached to the engine head cover 2, FIG. 5B is a side view showing a state where the attachment is completed, and FIG. 5C is a leaf spring. It is an expansion perspective view of the terminal 7a.

As shown in FIG. 2B, positioning protrusions 3d and 3d extending in the vertical direction are formed on both side surfaces of the ignition coil head 3a adjacent to the terminal portion 7.
The positioning protrusions 3d and 3d are formed in the engagement groove 2 formed on the inner circumference of the coil housing portion 2a of the engine head cover 2.
The ignition coil 3 is positioned in the horizontal direction by inserting the ignition coil 3 into the housing 2a so as to engage with g and 2g (see FIG. 3). At this time, the leaf spring-shaped terminal 7a of the terminal portion 7 provided on one side surface of the head 3a is positioned so as to face the film-shaped terminal 5 of the coil housing portion 2a. Since each leaf spring terminal 7a is biased toward the outer peripheral side of the ignition coil 3 (that is, the film-shaped terminal 5 side), each leaf spring terminal 7a is pressed against the film terminal 5 and electrically connected. Becomes

As shown in FIG. 1 or 2, the design cover 4 is fitted so as to cover the entire upper surface of the engine head cover 2 and presses the ignition coil head 3a housed in the coil housing 2a. It is a vibrating resin member. The lower surface of the design cover 4 is formed so as to substantially conform to the outer shape of the upper surface of the engine head cover 2 and the ignition coil head 3a attached thereto.
Is fitted so as to be substantially in close contact with the upper surface of the. Further, a vibration-proof rubber 4a is attached to a portion of the lower surface of the design cover 4 that abuts the ignition coil head 3a, and the vibration of the ignition coil 3 is suppressed by elastically pressing and urging the ignition coil head 3a. It has become.

In the above embodiment, the anti-vibration rubber 4 is used.
a is the vibration-proof member of the present invention, the film-like terminal 5 is a connecting terminal, the leaf spring-like terminal 7a is a connected terminal, the terminal protection projection 7b is a wall-like projection, and the seal rubber 3c is a sealing member (claim 1). 7) respectively.

Next, the operation of each part of the internal combustion engine ignition device 1 of the present embodiment having the above-described structure will be described.

In the ignition device 1 for an internal combustion engine, the ignition coil head 3 in which the design cover 4 is housed in the coil housing 2a.
Since a is pressed and urged, the ignition coil 3 can be fixed to the engine head cover 2 without using screws. Therefore, when the ignition coil 3 is attached or detached, it is not necessary to attach or detach the screw, so that the workability is remarkably improved.

Further, since the design cover 4 is fitted so as to cover the entire upper surface of the engine head cover 2, rainwater can be prevented from entering the plug hole 22 through the coil housing 2a. Further, since the ring-shaped packing 6 is attached so as to surround the coil housing 2a, moisture such as rainwater does not enter the coil housing 2a, and the metal leaf spring terminals 7a and the like. It is possible to prevent the film-shaped terminal 5 from being corroded by rainwater or the like.

Further, since the design cover 4 elastically supports the ignition coil head 3a via the antivibration rubber 4a, the vertical vibration of the ignition coil 3 is prevented and the vibration of the ignition coil 3 is prevented. It is also possible to prevent the leaf spring-shaped terminal 7a and the film-shaped terminal 5 from being worn out.

In addition, even if a small amount of blow-by gas leaks from the combustion chamber 23, the plug hole 2
2 through the coil insertion hole 2b, through the breathing hole 2e which is a separate room from the coil housing 2a, and is reliably discharged into the atmosphere in the external space through the gap between the wide portion 2f of the concave groove 2d and the packing 6. It is possible to prevent the leaf spring-shaped terminal 7a, which is an electrical connection terminal, from directly touching.

Further, since the seal rubber 3c provided on the outer periphery of the lower side of the ignition coil head 3a closes the space on the cylindrical portion 3b side (that is, the plug hole 22 side), the blow-by gas containing sulfur and the like is made of metal. It is possible to prevent these metal terminals from being corroded by blow-by gas without directly touching the leaf spring-shaped terminals 7a and the film-shaped terminals 5 of FIG.

Further, since the adjacent leaf spring terminals 7a are respectively partitioned by the terminal protection projections 7b, it is possible to prevent them from coming into contact with each other to cause a short circuit. It is also prevented from being deformed.

Further, since the leaf spring-shaped terminal 7a is bent so that the lower end portion of the vertically arranged metal plate is wound from the lower side to the upper side, the ignition coil 3 is mounted on the engine head cover 3. In doing so, the film-shaped terminal 5 can be smoothly pressed against the film-shaped terminal 5 without being caught. In addition, since the projection 7c is formed on the surface portion of the leaf spring-shaped terminal 7a that contacts the film-shaped terminal 5, it reliably contacts the film-shaped terminal 5 without causing problems such as poor contact.

Furthermore, the positioning projection 3d and the engaging groove 2g
Since they are engaged with each other, not only the positioning is easy at the time of mounting the ignition coil 3 but also the vibration of the ignition coil 3 in the horizontal direction is prevented.
Also, abrasion of the film terminal 5 is prevented.

Next, regarding the second embodiment of the present invention,
This will be described with reference to FIG. The same components as those in the first embodiment described above are designated by the same reference numerals, and detailed description thereof will be omitted.

FIG. 6A is a perspective view showing a state in which the ignition coil 3 is being inserted into the plug hole 22. In the second embodiment, as shown in FIG. 6A, the packing 8 is attached over the entire circumference in the vicinity of the upper part of the inner circumference of the coil housing portion 2a. In the packing 8, a ribbon-shaped plate-shaped portion 8a made of a rubber material is formed in a quadrangular frame shape along the inner circumference of the coil housing portion 2a, and a protrusion 8b is formed at the center position in the width direction of the plate-shaped portion 8a. Formed (Fig. 6
(See the cross-sectional view of (b)). When the ignition coil 3 is inserted into the plug hole 22, the packing 8 is located above the terminal portion 7 (that is, on the side opposite to the plug direction),
The protrusion 8b of the packing 8 that protrudes toward the inner peripheral side comes into close contact with the side surface 3e of the head 3a. Further, the side surface 3e of the head portion 3a is provided so as to project to the outer peripheral side with respect to the terminal portion 7 provided therebelow.

Therefore, since the packing 8 is interposed between the head 3a and the engine head cover 2 (specifically, between the side surface 3e and the inner peripheral surface of the coil housing 2a), the packing 8 is located above the head 3a. Even if water enters from above with the provided design cover 4 removed, the leaf spring terminal 7 of the terminal portion 7
a and the film terminal 5 are prevented from being exposed to water.
The packing 8 constitutes the sealing member in claim 9.

Next, regarding the third embodiment of the present invention,
This will be described with reference to FIGS. 7 and 8. 7 is a vertical cross-sectional view of the internal combustion engine ignition device 31 according to the third embodiment, and FIG. 8 shows a leaf spring-shaped terminal 7a and a film-shaped terminal 5 indicated by an arrow B in FIG. It is an enlarged view which expands and shows the contact part vicinity.

In this embodiment, the ignition coil 33 is
The head portion 33a is formed in a cylindrical shape whose diameter is reduced stepwise toward the lower side, and a plurality of stepped portions 33b (for example, four in the embodiment of FIG. 7) forming the stepped outer peripheral surface are respectively covered. A leaf spring terminal 7a is provided as a connection terminal. The four leaf spring terminals 7a are for power supply,
It is set as a terminal for grounding, ignition signal, and ignition monitor signal.

On the other hand, in the engine head cover 32, the inner peripheral surface of the coil accommodating portion 32a is formed in a step shape in which the inner peripheral surface is aligned with the outer peripheral surface of the ignition coil head 33a, and a plurality of (four) inner step surfaces are formed. A film-shaped terminal 5 as a connection terminal is provided on each of the step portions 32b along the inner peripheral surface of the coil housing portion 32a in a closed curve shape. The four film-shaped terminals 5 correspond to the above-mentioned leaf spring-shaped terminals 7a, respectively.

The ignition coil 33 is attached to the coil insertion hole 32c of the engine head cover 2 and the engine head 2.
When the head portion 33a is inserted into the plug hole 22 of one and the head portion 33a is housed in the coil housing portion 32a, the leaf spring-shaped terminals 7a respectively provided on the four step portions 33b forming the stepwise outer peripheral surface of the ignition coil 33. And the engine head cover 32
Forming a staircase-shaped inner peripheral surface of the coil storage portion 32a of 4
The film-shaped terminals 5 provided on the individual step portions 32b
And abut.

According to this embodiment, the ignition coil head 33
Since a is formed in a columnar shape whose diameter decreases in a stepwise manner downward, there is no mounting directionality in the plane that is orthogonal to the axial direction in the coil housing portion 32a. Further, since the film-shaped terminal 5 is formed in a closed curve shape along the inner peripheral surface of the coil housing portion 32a and the terminal portion is exposed over the entire inner peripheral surface of the coil housing portion 32a, the ignition coil 33 is coiled. The leaf spring-shaped terminal 7a always comes into contact with the film-shaped terminal 5 regardless of the direction in which it is assembled in the housing portion 32a in the plane orthogonal to the axial direction, and electrical connection between both terminals is ensured. . Therefore, the ignition coil 33 can be extremely easily assembled to the engine head cover 32, and the number of assembly work steps can be reduced.

It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

For example, in each of the above-described embodiments, the leaf spring-shaped terminal 7a is provided on the ignition coil 3 side and the film-shaped terminal 5 is provided on the engine head cover 2 side, but they may be replaced with each other. . In short, one of the terminals provided on the ignition coil and the engine head cover may be a leaf spring terminal and the other may be a film terminal. The number of terminals of the ignition coil 33 and the engine head cover 2 may be two or more.

In the third embodiment, the ignition coil head 33a has a cylindrical shape, but the shape is not limited to this. For example, when the ignition coil head 33a is formed in a square shape in a plan view and the inner peripheral surface of the coil storage portion 32a is also formed in a square shape in a plan view, the outer peripheral surface of the ignition coil head 33a and the inner peripheral surface of the coil storage portion 32a. It suffices to assemble so as to match with each other, and it is not necessary to consider the directionality of the assembly in the plane orthogonal to the axial direction of the ignition coil head 33a.

In the third embodiment, the film-shaped terminal 5 has a closed curve shape so that the terminal portion is exposed over the entire inner peripheral surface of the coil housing portion 32a. The terminal portion may be exposed in an arc shape so as to extend along a part of the surface. In this modification, it is necessary to assemble the ignition coil 33 into the engine head cover 32 so that the leaf spring-shaped terminal 7a contacts the film-shaped terminal 5, but it is necessary to assemble the ignition coil 33 so as to extend along a part of the inner peripheral surface of the coil housing 32a. Since the film-shaped terminals 5 are exposed in an arc shape, it is possible to easily perform the alignment.

[0069]

As described above, according to the ignition device for an internal combustion engine according to claim 1 of the present invention, the design cover presses and urges the head portion of the ignition coil. Since there is no need to fix it, the work of fastening or loosening the screw at the time of mounting or removing the ignition coil becomes unnecessary, and there is an effect that the efficiency of the work of mounting or removing the ignition coil is significantly improved.

Further, according to the ignition device for an internal combustion engine of the second aspect, the ignition coil is strongly pressed and urged by the vibration isolating member, and the ignition coil head is elastically pressed to ignite the ignition coil. This has the effect of preventing vibration of the coil.

Further, according to the ignition device for an internal combustion engine of the third aspect, there is an effect that electrical connection can be easily achieved only by mounting the ignition coil on the engine head cover. Further, since it is not necessary to crawl a connecting sub-harness and the like in the engine room, there is an effect that the engine room can be made compact and lightweight.

In addition, according to the ignition device for an internal combustion engine of claim 4, even if a small amount of blow-by gas leaks from the combustion chamber of the engine into the plug hole, the coil accommodating portion having the connection terminal is provided. The effect that it is reliably discharged into the atmosphere of the external space through the breathing hole formed in the separate room is exerted. Further, since the seal member is provided on the outer periphery of the lower side of the ignition coil head, the connecting terminal and the connected terminal in the coil housing portion do not come into contact with the blow-by gas containing the sulfur content, etc., and corrosion of these terminals is prevented. There is an effect that it can be prevented. Furthermore, since packing is provided around the coil housing, moisture such as rainwater does not enter the coil housing, and it is possible to prevent the connection terminals and the connected terminals from being corroded by moisture from the outside. Play.

According to the internal combustion engine ignition device of the present invention, when the ignition coil is housed in the coil insertion hole of the engine head cover and the plug hole of the engine head, the inner circumference of the coil insertion hole of the engine head cover is reduced. The connection terminal exposed on the surface abuts the connected terminal provided on the ignition coil. Therefore, the effect that the electrical connection with the engine control device can be easily achieved only by mounting the ignition coil on the engine head cover.
Further, since it is not necessary to crawl the connecting sub-harness and the like in the engine room, there is an effect that the engine room can be made compact and lightweight, the cost can be reduced, and the appearance can be improved.

According to the ignition device for an internal combustion engine of the sixth aspect, when the ignition coil head is housed in the coil housing part, the leaf spring-like terminal press-contacts the film-like terminal. The effect is that electrical connection can be achieved easily and reliably.

Further, according to the ignition device for an internal combustion engine of the seventh aspect, when the ignition coil head is housed by moving the ignition coil head relatively downward in the coil housing part, the leaf spring-like terminal is a film-like terminal. The effect of smoothly abutting without being caught on is exerted. Further, since the projections of the leaf spring-shaped terminal are surely brought into contact with the film-shaped terminal, it is possible to prevent the occurrence of contact failure.

Further, according to the ignition device for an internal combustion engine of claim 8, since the adjacent leaf spring-like terminals are partitioned by the wall-shaped projections, they are prevented from coming into contact with each other and short-circuiting. It has the effect of being able to.

Further, according to the ignition device for an internal combustion engine of the ninth aspect, since the seal member seals between the ignition coil and the engine head cover, it is possible to prevent the connected terminals from being exposed to water. Play.

According to the ignition device for an internal combustion engine of the tenth aspect, when the ignition coil is housed in the coil insertion hole of the engine head cover and the plug hole of the engine head, the stepped outer peripheral surface of the ignition coil is removed. The connected terminals provided on each of the plurality of formed step portions and the connection terminals provided on each of the plurality of step portions forming the stepped inner peripheral surface of the coil housing portion of the engine head cover come into contact with each other. One of the connection terminal and the connected terminal is a film-shaped terminal provided along the outer peripheral surface of the ignition coil head or the inner peripheral surface of the coil housing portion, and the other is biased toward the film-shaped terminal side. Since it is composed of the leaf-spring-like terminals that are pressed into pressure contact with each other, there is an effect that electrical connection can be easily and reliably achieved between both terminals.

Further, according to the ignition device for an internal combustion engine of the eleventh aspect, since the ignition coil head is formed in a columnar shape whose diameter decreases in a stepwise manner downward, the shaft relative to the engine head cover is reduced. Since there is no directivity in the assembling in the plane orthogonal to the direction, the assembling can be performed extremely easily, and the number of assembling work steps can be reduced.

According to the ignition device for an internal combustion engine of the twelfth aspect, the film-shaped terminal is formed in a closed curve shape along the outer peripheral surface of the ignition coil head or the inner peripheral surface of the coil housing portion, and the terminal portion is formed. Is exposed over the entire circumference of the outer peripheral surface of the ignition coil head or the inner peripheral surface of the coil housing portion, so that the ignition coil can be assembled in any direction with respect to the coil housing portion of the engine head cover, The leaf spring-like terminal is always brought into contact with the film-like terminal, so that the electrical connection between both terminals can be surely achieved. Therefore, the ignition coil can be attached to the engine head cover extremely easily, and the number of assembling steps can be reduced.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of an internal combustion engine ignition device according to a first embodiment of the present invention.

2A is a cross-sectional view of an internal combustion engine ignition device, and FIG. 2B is a front view of a terminal portion when the ignition device of FIG.

FIG. 3 is an exploded perspective view showing a coil housing portion and a packing of the engine head cover.

FIG. 4 is a perspective view of an ignition coil.

5A and 5B are explanatory views of a leaf spring-shaped terminal, FIG. 5A is a side view showing a state immediately before mounting the ignition coil on an engine head cover, and FIG. 5B is a side view showing a state where the mounting of the ignition coil is completed. , (C) are enlarged perspective views of leaf spring terminals.

FIG. 6A is a perspective view showing a state in which the ignition coil is being inserted in the ignition device for an internal combustion engine according to the second embodiment of the present invention, and FIG. 6B is an enlarged sectional view of the packing 8. .

FIG. 7 is a cross-sectional view of an internal combustion engine ignition device according to a third embodiment.

FIG. 8 is an enlarged view showing the vicinity of a contact portion between a leaf spring-shaped terminal and a film-shaped terminal in an enlarged manner.

FIG. 9 is a sectional view showing an example of a conventional ignition device for an internal combustion engine.

[Explanation of symbols]

1 Internal combustion engine ignition device (first embodiment) 2 engine head cover 2a coil storage 2b Coil insertion hole 2e Breathing hole 3 ignition coil 3a head 3b tube 3c seal rubber 4 Design cover 4a Anti-vibration rubber 5 Film terminals 6 packing 7 terminals 7a leaf spring terminal 7b Terminal protection protrusion 7c Launching protrusion 8 packing 31 Internal Combustion Engine Ignition Device (Third Embodiment) 32 engine head cover 32a coil storage section 32b step 32c coil insertion hole 33 ignition coil 33a head 33b step

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tokuichi Fujiyama             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO (72) Inventor Masahiko Aoyama             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO (72) Inventor Yu Fukuda             206-1 Nunobikihara, Haibara-cho, Haibara-gun, Shizuoka Prefecture Yazaki             Parts Co., Ltd. (72) Inventor Hideto Kumakura             206-1 Nunobikihara, Haibara-cho, Haibara-gun, Shizuoka Prefecture Yazaki             Parts Co., Ltd. (72) Inventor Chiyama Takayama             1 Toyota Town, Toyota City, Aichi Prefecture Toyota Auto             Car Co., Ltd. (72) Inventor Nobuhiro Takada             1 Toyota Town, Toyota City, Aichi Prefecture Toyota Auto             Car Co., Ltd. (72) Inventor Isao Yoneyama             1 Toyota Town, Toyota City, Aichi Prefecture Toyota Auto             Car Co., Ltd. F term (reference) 3G019 KA12 KB08 KB09 KC10                 3G024 AA71 AA72 BA00 DA01 DA18

Claims (12)

[Claims] 1. A concave coil accommodating portion is provided on an upper surface, and a coil insertion hole is formed on a bottom surface of the coil accommodating portion so as to communicate with a plug hole of an engine head, and is attached so as to cover an upper portion of the engine head. The engine head cover, the plug hole and a cylindrical portion that is inserted into the coil insertion hole that communicates with the plug hole, and a head that is provided at an upper end of the cylindrical portion and has a diameter larger than that of the cylindrical portion. An ignition coil mounted on the engine head cover in a state of being housed in the housing, and a design cover for pressing and urging the head of the ignition coil housed in the coil housing. Ignition device for internal combustion engine. 2. The ignition device for an internal combustion engine according to claim 1, wherein a vibration damping member is provided on at least a portion of the lower surface of the design cover that abuts on the head portion of the ignition coil. 3. The engine head cover is provided so that at least a part of the connection terminals electrically connected to the engine control device is exposed to the inner peripheral surface of the coil housing, and the head of the ignition coil is provided. 3. The ignition device for an internal combustion engine according to claim 1, wherein a connected terminal is provided on an outer periphery of the head, the connected terminal being in contact with the connection terminal in a state where the head is housed in the coil housing. 4. A packing provided around the coil housing, and a seal member provided on an outer periphery under the ignition coil head are further provided, and the coil insertion hole is provided in the engine head cover. The ignition device for an internal combustion engine according to claim 3, wherein a breathing hole that communicates with an external space is formed in a room separate from the coil housing portion. 5. An engine head cover, which covers an upper portion of an engine head having a plug hole and has a coil insertion hole communicating with the plug hole, and an ignition coil housed in the coil insertion hole and the plug hole. In the ignition device for an internal combustion engine including, the engine head cover has a connection terminal that is exposed to an inner peripheral surface of the coil insertion hole and is electrically connected to an engine control device, and the ignition coil is An ignition device for an internal combustion engine, comprising: a connected terminal that abuts the connection terminal while the ignition coil is housed in the plug hole. 6. One of the connection terminal and the connected terminal is a film-like terminal, and the other is a leaf spring-like terminal that is pressed against the film-like terminal and is in pressure contact therewith. Item 6. An ignition device for an internal combustion engine according to any one of items 3 to 5. 7. The leaf spring-shaped terminal is formed by bending a lower end portion of a metal plate arranged in a vertical direction so as to be wound from a lower side to an upper side, and punching a protrusion on a surface portion abutting the film-shaped terminal. The ignition device for an internal combustion engine according to claim 6, wherein the ignition device is formed. 8. The internal combustion engine according to claim 6, wherein a plurality of the plate spring-like terminals are juxtaposed, and a wall-shaped projection is formed between adjacent plate spring-like terminals. Ignition device. 9. A seal member for sealing between the ignition coil and the engine head cover is provided on the side opposite to the plug with respect to the connected terminal, according to any one of claims 3 to 8. An ignition device for an internal combustion engine as described. 10. The ignition coil is formed such that a head portion thereof is reduced in diameter downward in a stepwise manner, and the connected terminals are respectively provided in a plurality of stepped portions forming the stepped outer peripheral surface. The engine head cover is formed in a step-like manner such that an inner peripheral surface of a coil housing portion that houses the ignition coil head is aligned with an outer peripheral surface of the ignition coil head, and a plurality of step-shaped inner peripheral surfaces are formed. The connection terminal is provided on each of the stepped portions, and one of the connection terminal and the connected terminal is provided along the outer peripheral surface of the ignition coil head or the inner peripheral surface of the coil housing portion. The ignition device for an internal combustion engine according to any one of claims 6 to 9, wherein the ignition device is formed of a terminal, and the other is formed of the leaf spring-shaped terminal that is urged toward the film-shaped terminal side to come into pressure contact therewith. 11. The ignition device for an internal combustion engine according to claim 10, wherein the ignition coil is formed in a columnar shape whose head has a diameter that decreases stepwise downward. 12. The film-shaped terminal according to claim 10 or 11, wherein the film-shaped terminal is formed in a closed curved shape along an outer peripheral surface of the ignition coil head or an inner peripheral surface of the coil housing portion. Ignition device for internal combustion engine.