JP2002227755A - Ignition coil for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ignition coil for an engine capable of reducing wear of connection part due to engine vibration. SOLUTION: Since a spring 42 has a smaller winding diameter at both ends 42a and 42b than a winding diameter at a center part 42c, a spring load of the spring 42 is increased to reduce contact resistances at a connection part of one end 42a of the spring 42 with a high-tension terminal 41 and a connection part of another end 42b of the spring 42 with a coil side terminal 111 of an ignition plug 110. Consequently, wear of the connection parts of the spring 42 with the high-tension terminal 41 and the ignition plug 110 from engine vibration can be reduced to prevent disturbing conduction of very small electric current such as ion current and to make detection of very small electric current easy. Misjudgment with an ignition monitor utilizing change of very small electric current in a secondary side can be prevented. Desired high voltage thereby can be applied to the ignition plug 110.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ignition coil for an internal combustion engine, and more particularly to a stick-shaped ignition coil directly mounted on a plug hole of an internal combustion engine (hereinafter, the "internal combustion engine" is referred to as an engine).

[0002]

2. Description of the Related Art A conventional stick-shaped ignition coil is mounted directly on a plug hole formed in an engine block, for example, as shown in FIG. ing.
The case 101 is formed of an insulating resin and houses a primary coil and a secondary coil (not shown). The high voltage terminal 103 is electrically connected to the high voltage side of the secondary coil, and one end 104 a of the spring 104 is electrically connected to the high voltage terminal 103. The rubber cap 102 is fitted to the high voltage side end of the case 101, and the ignition plug 110 is fitted to the rubber cap 102. When the ignition plug 110 is fitted into the rubber cap 102, the other end 104b of the spring 104 and the coil side terminal 111 of the ignition plug 110 come into contact with each other, the spring 104 is compressed, and the high voltage terminal 103 and the ignition plug 110 are electrically connected. Connecting.

[0003]

However, in the ignition coil 100 having the above structure, the spring 104 is rubbed between the high-voltage terminal 103 and the coil-side terminal 111 of the ignition plug 110 by the vibration of the engine. Wear may occur at the connection with the high-voltage terminal 103 and at the connection between the other end 104b of the spring 104 and the coil-side terminal 111 of the ignition plug 110, which may hinder conduction of a weak current such as an ion current. In such a state, there is a problem that an erroneous determination is made in the ignition monitor using the change in the secondary-side weak current.

Further, the other end 104b of the spring 104 and the coil side terminal 111 of the spark plug 110 are momentarily separated due to the vibration of the engine, so that electrical connection cannot be established, which may hinder ignition and current detection. . Further, a space for holding the spring 104 in the ignition coil 100 is required, and there is a problem that it is difficult to reduce the size of the high voltage side.

Further, in the plug connection of the high-voltage cord, the plug is connected by a C-shaped leaf spring having an inner diameter smaller than that of the coil side terminal of the ignition plug, and the plug connection portion is initially worn by the urging force of the C-shaped leaf spring. There was a problem of fear.

The present invention has been made to solve such a problem, and an object of the present invention is to provide an ignition coil for an engine that reduces wear of a connecting portion due to engine vibration.

Another object of the present invention is to provide an engine ignition coil for applying a desired high voltage to a spark plug. Still another object of the present invention is to provide an ignition coil for an engine that ensures conduction of an ion current.

Another object of the present invention is to provide an ignition coil for an engine which prevents erroneous determination in an ignition monitor. Still another object of the present invention is to provide an ignition coil for an engine that facilitates detection of a weak current.

Yet another object of the present invention is to provide an ignition coil for an engine in which the rigidity of the plug connection is increased. Yet another object of the present invention is to provide an ignition coil for an engine that prevents water from entering a connection portion.

It is still another object of the present invention to provide an ignition coil for an engine, which reduces poor conduction at a connection portion. It is still another object of the present invention to provide an ignition coil for an engine in which the contact of a connecting portion is stable.

Still another object of the present invention is to provide an ignition coil for an engine which prevents initial wear of a plug connection portion. Still another object of the present invention is to provide an ignition coil for an engine in which a fitting force of a plug connection part is increased.

It is still another object of the present invention to provide an ignition coil for an engine which reduces vibration of a connection portion. Still another object of the present invention is to provide an ignition coil for an engine that ensures a stable contact resistance of a connection portion.

Still another object of the present invention is to provide an ignition coil for an engine which reduces a contact failure of a connecting portion. Still another object of the present invention is to provide an ignition coil for an engine that improves the degree of closeness of a plug connection portion.

It is still another object of the present invention to provide an ignition coil for an engine which has a small size. Still another object of the present invention is to provide an ignition coil for an engine in which the number of parts is reduced and the manufacturing cost is reduced.

It is still another object of the present invention to provide an ignition coil for an engine which reduces the number of assembly steps and the manufacturing cost.

According to the ignition coil for an engine of the present invention, the high voltage side of the secondary coil and one end are electrically connected, and the ignition plug is inserted and inserted. Since the elastic member electrically connecting the high voltage side of the secondary coil and the ignition plug is compressed by the contact of the other end with the spark plug, the elastic force at the center is larger than the elastic force at both ends. And the contact resistance between the high voltage side of the secondary coil and the connection portion with the ignition plug can be reduced. Therefore, abrasion of the connection between the elastic member, the secondary coil at the high voltage side, and the spark plug due to the vibration of the engine can be reduced.

Further, by reducing the wear of the connecting portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to use an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, the high voltage side of the secondary coil is electrically connected to one end of the secondary coil. The spring, which is compressed by contact and electrically connects the high voltage side of the secondary coil and the ignition plug, has a larger winding diameter at the center than at both ends, so that the spring load of the spring increases and the elastic member And the contact resistance between the high voltage side of the secondary coil and the connection portion with the ignition plug can be reduced. Therefore, abrasion of the connection between the elastic member, the secondary coil at the high voltage side, and the spark plug due to the vibration of the engine can be reduced.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of the weak current, and to make use of the secondary-side weak current change. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the third aspect of the present invention, one end is electrically connected to the high voltage terminal, and the other end of the ignition plug comes into contact with the ignition plug when the ignition plug is inserted and compressed. The elastic member that electrically connects the high voltage side of the secondary coil and the ignition plug can be fitted into a groove formed in one or both of the ignition coil and the high voltage terminal. The connection between the one end and the high-voltage terminal and the connection between the other end of the elastic member and the spark plug can be prevented from being rubbed. Therefore, it is possible to reduce the wear of the connection between the elastic member, the high voltage side of the secondary coil and the spark plug.

Further, by reducing the abrasion of the connecting portion, it is possible to prevent the conduction of a weak current such as an ionic current from being hindered, to facilitate the detection of a weak current, and to use an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the fourth aspect of the present invention, the ignition coil is electrically connected to the inner wall of the first groove formed in the high voltage terminal electrically connected to the high voltage side of the secondary coil. And a wire terminal that comes into contact with the ignition plug when the ignition plug is inserted and electrically connects the high voltage side of the secondary coil and the ignition plug,
Since the ignition coil has the second groove into which the above-mentioned wire rod terminal can be fitted, it is possible to prevent the connection between the wire rod terminal, the high voltage terminal and the ignition plug from being rubbed by the vibration of the engine. Therefore, it is possible to reduce the wear of the connection between the wire terminal and the high voltage side of the secondary coil and the spark plug.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to make use of a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, the covering member provided on the outer periphery of the plug cap suppresses the radial expansion of the plug cap.
The rigidity of the plug connection is increased, and it is possible to prevent the vibration of the engine from rubbing the connection between the elastic member, the high voltage side of the secondary coil, and the ignition plug. Therefore, it is possible to reduce the wear of the connection between the elastic member, the high voltage side of the secondary coil and the spark plug.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to perform ignition using a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, the covering member extending from the case to the high voltage side covers the outer periphery of the plug cap.
The rigidity of the plug connection is increased, and it is possible to prevent the vibration of the engine from rubbing the connection between the elastic member, the high voltage side of the secondary coil and the spark plug. Therefore, it is possible to reduce the wear of the connection between the elastic member, the high voltage side of the secondary coil and the spark plug.

Furthermore, by reducing the wear of the connection portion, it is possible to prevent the conduction of a weak current such as an ionic current from being hindered, to facilitate the detection of a weak current, and to use an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, the ignition coil is electrically connected to the high voltage side of the secondary coil. The elastic member that contacts and electrically connects the high voltage side of the secondary coil and the ignition plug is provided in the case and is housed in the housing chamber having the tapered surface, so that the contact of the plug connection portion is stable, It is possible to prevent the connection between the elastic member, the high voltage side of the secondary coil, and the ignition plug from being rubbed by the vibration of the engine. Therefore, it is possible to reduce the wear of the connection between the elastic member, the high voltage side of the secondary coil and the spark plug.

Further, by reducing the wear of the connection portion and stabilizing the contact, it is possible to reduce the contact failure of the connection portion and prevent the conduction of a weak current such as an ion current from being hindered.
It is possible to easily detect a weak current and prevent an erroneous determination in an ignition monitor using a change in the secondary-side weak current. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, the secondary coil is electrically connected at one end to the high voltage side, and when the ignition plug is inserted, the ignition plug and the other end are connected. The other end of the elastic member that is compressed by contact and electrically connects the high voltage side of the secondary coil to the spark plug has a larger inner diameter than the tip of the spark plug before the spark plug is inserted. In addition, it is possible to prevent initial wear of the plug connection portion when the ignition plug is inserted.

According to the ignition coil for an engine of the ninth aspect of the present invention, the inner wall surface having the same shape as the outer peripheral shape of the fitting portion of the ignition plug is provided on the inner periphery of the plug cap. The fitting force with the spark plug increases. For this reason, the vibration of the connecting portion due to the vibration of the engine is reduced, and it is possible to prevent the contact failure between the elastic member and the high voltage side of the secondary coil and the connecting portion with the ignition plug. Therefore, it is possible to secure a stable contact resistance of the connection portion, reduce conduction failure, facilitate detection of a weak current, and prevent an erroneous determination in an ignition monitor using a change in a secondary-side weak current. it can. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the tenth aspect of the present invention, the means for strengthening the contact with the outer wall of the fitting portion of the ignition plug by tightening the plug cap in the longitudinal direction is provided on the inner wall of the plug cap. Therefore, the fitting force between the plug cap and the spark plug increases. For this reason, the vibration of the connecting portion due to the vibration of the engine is reduced, and it is possible to prevent the contact failure between the elastic member and the high voltage side of the secondary coil and the connecting portion with the ignition plug. Therefore,
It is possible to secure a stable contact resistance of the connection part, reduce conduction failure, facilitate detection of a weak current, and prevent erroneous determination in an ignition monitor that uses a change in a secondary-side weak current. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, one end of the elastic member for electrically connecting the high voltage side of the secondary coil and the ignition plug is pressed into the high voltage terminal in a radial direction, Since the other end is radially press-fitted into the spark plug by inserting the spark plug, a stable contact resistance of the plug connection can be secured, and the vibration of the engine causes the elastic member to be connected to the high-voltage terminal and the spark plug. The connection portion can be prevented from being rubbed. Therefore, it is possible to reduce the wear of the connection between the elastic member, the high-voltage terminal, and the ignition plug.

Further, by reducing the wear of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of the weak current, and to perform the ignition utilizing the change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, the conductive rubber electrically connected to the high voltage side of the secondary coil is electrically connected to the ignition plug when the ignition plug is inserted. And the electrical connection between the high voltage side of the secondary coil and the ignition plug, it is possible to secure a stable contact resistance of the plug connection, and the conductive rubber and the secondary coil Of the high voltage side and the electrical connection of the ignition plug can be prevented from being rubbed. Therefore, it is possible to reduce wear on the high voltage side of the secondary coil and the electrical connection portion of the ignition plug.

Further, by reducing the wear of the high voltage side of the secondary coil and the fitting portion of the ignition plug, it is possible to prevent the conduction of a weak current such as an ion current and to detect the weak current. This makes it easy to prevent an erroneous determination in an ignition monitor using a change in the secondary-side weak current. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the thirteenth aspect of the present invention, since the projecting portion capable of contacting the inner wall of the plug hole of the internal combustion engine is provided on the outer periphery of the case, one end of the elastic member and the secondary The radial vibration of the connection portion between the coil and the high voltage side and the connection portion between the other end of the elastic member and the ignition plug is reduced. Therefore, it is possible to prevent the connection between the elastic member, the high voltage side of the secondary coil and the ignition plug from being rubbed by the vibration of the engine, and reduce wear.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to perform an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, since the projecting portion which can be brought into contact with the inner wall of the plug hole of the internal combustion engine is provided on the outer periphery of the plug cap, one end of the elastic member is connected to the other end. The radial vibration of the connection between the secondary coil and the high voltage side and the connection between the other end of the elastic member and the spark plug is reduced. Therefore, it is possible to prevent the connection between the elastic member, the high voltage side of the secondary coil and the ignition plug from being rubbed by the vibration of the engine, and reduce wear.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to perform an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the fifteenth aspect of the present invention, the annular member capable of contacting the inner wall of the plug hole of the internal combustion engine is provided on the outer periphery of the case.
The radial vibration of the plug connection is reduced. Therefore, it is possible to prevent the plug connection portion from being rubbed by the vibration of the engine, and to reduce wear.

Further, by reducing the abrasion of the plug connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to perform ignition using a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thereby, a desired high voltage can be applied to the ignition plug.

According to the ignition coil for an engine of the present invention, the seal portion that is in close contact with the ignition plug and seals the electrical connection portion of the ignition plug is provided at the high voltage side end of the case. Therefore, the degree of adhesion of the plug connection part can be improved, and water can be prevented from entering the plug connection part.

Also, by eliminating the plug cap,
The physical size can be reduced, the number of parts can be reduced, the number of assembly steps can be reduced, and the manufacturing cost can be reduced.

According to the ignition coil for an engine of the present invention, the connecting portion electrically connected to the high voltage side of the secondary coil is formed by inserting the spark plug into the electrical connecting portion of the spark plug. Electrically connects the high-voltage side of the secondary coil and the spark plug, a reliable connection not affected by engine vibration is obtained, and vibration at the connection with the spark plug is reduced. For this reason, the connection portion with the ignition plug is prevented from being rubbed by the vibration of the engine,
Wear can be reduced. Therefore, it is possible to prevent the conduction of the weak current such as the ion current from being hindered, to facilitate the detection of the weak current, and to prevent an erroneous determination in the ignition monitor using the change in the secondary-side weak current. Thereby, a desired high voltage can be applied to the ignition plug.

Further, a spring for electrically connecting the high voltage side of the secondary coil to the ignition plug, a mounting flange for mounting the ignition coil to the engine, and the like can be eliminated, so that the physical size can be reduced. In addition, the number of parts can be reduced, the number of assembly steps can be reduced, and the manufacturing cost can be reduced.

According to the ignition coil for an engine of the eighteenth aspect of the present invention, the screw portion electrically connected to the high voltage side of the secondary coil can be rotated by inserting the ignition plug into the plug cap and rotating. Since it is connected to the electrical connection of the ignition plug and electrically connects the high voltage side of the secondary coil to the ignition plug, a reliable connection unaffected by engine vibration is obtained. Vibration is reduced. Therefore, it is possible to prevent the connection portion with the ignition plug from being rubbed by the vibration of the engine, and to reduce wear. Therefore, it is possible to prevent the conduction of the weak current such as the ion current from being hindered, to facilitate the detection of the weak current, and to prevent an erroneous determination in the ignition monitor using the change in the secondary-side weak current. Thereby, a desired high voltage can be applied to the ignition plug.

Further, since a spring for electrically connecting the high voltage side of the secondary coil to the ignition plug, a mounting flange for mounting the ignition coil to the engine, and the like can be eliminated, the physical size can be reduced. In addition, the number of parts can be reduced, the number of assembly steps can be reduced, and the manufacturing cost can be reduced.

[0048]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; (First Embodiment) FIG. 1 shows a main part of an ignition coil for an engine according to a first embodiment of the present invention. The ignition coil 10 shown in FIG. 1 is housed in a plug hole formed for each cylinder above an engine block (not shown).
10 and is electrically connected.

The case 11 of the ignition coil 10 is formed in a cylindrical shape from an insulating resin material. The case 11 includes a high voltage terminal 41 and a spring 42 as a high voltage part.
Is housed. A rubber plug cap 12 is fitted to the high-voltage end of the case 11. Plug cap 1
The spring 42 as an elastic member electrically connects the high voltage side of the secondary coil (not shown) and the ignition plug 110 by fitting the ignition plug 110 into one end of the second plug 2. The high voltage terminal 41 is insert-molded in the case 11 and is electrically connected to a wire (not shown) at the high voltage end of the secondary coil.

One end 42a of the spring 42 is electrically connected to the high voltage terminal 41. When the ignition plug 110 is inserted into the ignition coil 10, the other end 42 b of the spring 42 is electrically connected to the coil-side terminal 111 of the ignition plug 110.
1 and the ignition plug 110 are electrically connected. The winding diameter of both ends 42a and 42b of the spring 42 is
2 is smaller than the winding diameter of the central portion 42c. That is, the winding diameter of one end 42a of the spring 42 is φB,
When the winding diameter of the other end 42b of the spring 42 is φD and the winding diameter of the central portion 42c of the spring 42 is φC,

There is a relationship of φC> φB φC> φD. Thus, the spring load of the spring 42 is set to be larger than that of a spring having a uniform winding diameter. That is, the elastic force at the center of the elastic member is set to be larger than the elastic forces at both ends.

The case 11 has an annular projection 11a formed on the inner peripheral wall. The inner diameter of this projection 11a is φA
Then, since there is a relationship of φA <φC, the protrusion 11a serves to prevent the spring 42 from falling off.

In the first embodiment configured as described above,
Since the winding diameter of both ends 42a and 42b of the spring 42 is smaller than the winding diameter of the central part 42c of the spring 42, the spring load of the spring 42 increases, and the connection between the one end 42a of the spring 42 and the high-voltage terminal 41,
And the other end 42b of the spring 42 and the spark plug 11
It is possible to reduce the contact resistance of the connection portion with the zero coil side terminal 111. Therefore, the spring 42, the high voltage terminal 41 and the spark plug 1
It is possible to reduce the wear of the connection portion with the connector 10.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of the weak current, and to perform the ignition using a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the spark plug 110.

(Second Embodiment) FIG. 2 shows a main part of an engine ignition coil according to a second embodiment of the present invention. In the second embodiment, as shown in FIG. 2, the high-voltage terminal 43 electrically connected to the high-voltage side of the secondary coil has a thread-shaped groove 43a on the outer peripheral wall. One end 44a of 44 is fitted. The coil-side terminal 121 of the ignition plug 120 has a thread-shaped groove 121a on the outer peripheral wall, and the other end 44b of the spring 44 is fitted into the groove 121a. Thus, the spring 44 electrically connects the high-voltage terminal 43 and the ignition plug 120.

In the second embodiment having the above structure, the spring 4
4 are connected to the groove 43a of the high voltage terminal 43 and the coil side terminal 12 of the ignition plug 120.
1 is fitted into the groove 121a, and one end 44a of the spring 44 and the high voltage terminal 4
3 and the connection between the other end 44b of the spring 44 and the coil-side terminal 121 of the ignition plug 120 can be prevented from being rubbed. Therefore, the spring 44, the high-pressure terminal 43 and the spark plug 12
The wear of the connection part with zero can be reduced.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to perform an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the ignition plug 120.

In the second embodiment described above, the groove 43a and the groove 121a are formed in both the high voltage terminal 43 and the coil side terminal 121 of the ignition plug 120. However, in the present invention, the coil of the high voltage terminal or the coil of the ignition plug is formed. A groove may be formed in any one of the side terminals.

(Third Embodiment) FIG. 3 shows a main part of an engine ignition coil according to a third embodiment of the present invention. In the third embodiment, as shown in FIGS. 3A and 3B, a high voltage terminal 45 electrically connected to the high voltage side of the secondary coil has a first high voltage terminal 45 extending from the inner wall to the outer wall. Four groove portions 45a are formed as two groove portions, and two annular groove portions 131a as second groove portions are formed on the outer peripheral wall of the coil-side terminal 131 of the ignition plug 130. The two U-shaped wire rod terminals 46 are fitted into the groove 45 a of the high-voltage terminal 45 and the groove 131 a of the coil-side terminal 131 of the ignition plug 130. Thus, the wire rod terminal 46 electrically connects the high voltage terminal 45 and the ignition plug 130.

In the third embodiment, the wire terminal 46 is fitted in the groove 45a of the high-voltage terminal 45 and the groove 131a of the coil-side terminal 131 of the ignition plug 130. Of the high-voltage terminal 45 and the coil-side terminal 131 of the ignition plug 130 can be prevented from being rubbed. Therefore, it is possible to reduce the wear of the connection between the wire terminal 46 and the high-voltage terminal 45 and the ignition plug 130.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to use an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the ignition plug 130.

In the third embodiment described above, the two wire rod terminals 46 are used to fit the high-voltage terminal 45 and the coil-side terminal 131 of the ignition plug 130 at four locations. At least one wire terminal may be fitted to the high voltage terminal and the coil side terminal of the ignition plug.

(Fourth Embodiment) FIG. 4 shows a main part of an engine ignition coil according to a fourth embodiment of the present invention. In the fourth embodiment, as shown in FIG. 4, the case 13 is formed in a cylindrical shape from an insulating resin material. Case 13
Accommodates a spring 47, and has an outer peripheral portion 13a provided to extend toward the high voltage side. A plug cap 14 made of rubber is fitted to the high voltage side end of the case 13, and the plug cap 14 is covered by an outer peripheral portion 13 a of the case 13 as a covering member. When the ignition plug 110 is inserted into one end of the plug cap 14, the spring 47 as an elastic member electrically connects the high voltage side of the secondary coil (not shown) to the ignition plug 110. The other end of the plug cap 14 is provided with a fitting portion 14 a that fits with the high-voltage side end of the case 13.

In the fourth embodiment having the above structure, since the outer peripheral portion 13a of the case 13 having high rigidity covers the plug cap 14, the radial expansion of the plug cap 14 is suppressed. For this reason, the rigidity of the plug connection is increased, and the connection between the spring 47 and the high voltage side of the secondary coil and the coil side terminal 111 of the ignition plug 110 can be prevented from being rubbed by the vibration of the engine. Therefore, it is possible to reduce the wear of the connection between the spring 47, the high voltage side of the secondary coil, and the ignition plug 130.

Further, by reducing the wear of the connection portion, it is possible to prevent the conduction of a weak current such as an ionic current from being hindered, to facilitate the detection of a weak current, and to use an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the spark plug 110.

In the fourth embodiment described above, the outer peripheral portion 13a of the case 13 covers the plug cap 14. However, in the present invention, a highly rigid metal cover provided separately from the case is provided. It may be configured to cover the plug cap with the like.

(Fifth Embodiment) FIG. 4 shows an engine ignition coil according to a fifth embodiment of the present invention. In the fifth embodiment, as shown in FIGS. 5A and 5B, case 1
Reference numeral 5 denotes a cylindrical shape made of an insulating resin material. The case 15 houses a spring 47, and the inner wall surface 15a of this housing chamber is formed in a tapered shape such that the inner diameter decreases as it goes upward in FIG. The high voltage terminal 49 is insert-molded in the case 15 and is electrically connected to a wire (not shown) at the high voltage end of the secondary coil. One end 47a of the spring 47 is electrically connected to the high voltage terminal 49. The other end 47b of the spring 47 is in contact with the thin leaf spring 50. Thin leaf spring 50 as an elastic member
5A is provided along the inner wall surface 15a of the case 15, so that the inner diameter of the thin plate spring 50 is smaller than the outer diameter of the coil side terminal 111 of the ignition plug 110 before the insertion of the ignition plug 110 shown in FIG. Greater than. A rubber plug cap 16 is fitted to the high-voltage end of the case 15. As shown in FIG. 5B, when the spark plug 110 is inserted into one end of the plug cap 16, the coil-side terminal 111 of the spark plug 110 comes into contact with the thin plate spring 50, and the thin plate spring 50 The other end 4 of 47
5 together with 7b, the leaf spring 50 closes along the inner wall surface 15a of the case 15, the inner diameter of the leaf spring 50 becomes smaller, and comes into contact with the side of the coil side terminal 111 of the ignition plug 110. . The spring 47 electrically connects the high voltage side of the secondary coil (not shown) and the ignition plug 110 via the thin plate spring 50.

In the fifth embodiment having the above-described structure, the plug connection portion is located above and below the coil side terminal 111 of the ignition plug 110 via the thin plate spring 50, and the spring 47 is connected to the high voltage terminal 49 by the vibration of the engine. And the coil side terminal 11 of the thin plate spring 50 and the ignition plug 110
Rubbing of the connecting portion with the first member can be prevented.
Therefore, it is possible to reduce the wear of the connection between the spring 47 and the high-voltage terminal 49 and the connection between the thin plate spring 50 and the coil-side terminal 111 of the ignition plug 110.

Further, by reducing the wear of the connection portion and stabilizing the contact, it is possible to reduce the contact failure of the connection portion and prevent the conduction of weak current such as ion current from being hindered.
It is possible to easily detect a weak current and prevent an erroneous determination in an ignition monitor using a change in the secondary-side weak current. As a result, a desired high voltage is applied to the spark plug 1
10 can be applied.

Further, since the inner diameter of the thin plate spring 50 is larger than the outer diameter of the coil-side terminal 111 of the spark plug 110 before the insertion of the spark plug 110,
It is possible to prevent initial wear of the plug connection portion when the plug 10 is inserted.

(Sixth Embodiment) FIG. 6 shows a main part of an engine ignition coil according to a sixth embodiment of the present invention. Components that are substantially the same as those of the fifth embodiment shown in FIG.

In the sixth embodiment, as shown in FIG. 6, a plug cap 17 made of rubber is fitted to the end of the case 15 on the high voltage side. It has an inner peripheral portion 17a having the same shape as the insulator outer peripheral portion 110a as a portion. Plug cap 1
7, the outer peripheral portion 110a of the insulator of the spark plug 110 and the inner peripheral portion 17a of the plug cap 17 are fitted, and a spring 47 as an elastic member is not shown. The high voltage side of the next coil and the spark plug 110 are electrically connected.

In the sixth embodiment having the above structure, the inner peripheral portion 17a of the plug cap 17 has the same shape as the outer peripheral portion 110a of the spark plug 110, so that the fitting force between the plug cap 17 and the spark plug 110 increases. . Therefore, the vertical vibration in FIG. 6 due to the vibration of the engine is reduced.
Poor contact at the connection between the spring 47 and the coil side terminal 111 of the high voltage terminal 49 and the ignition plug 110 can be prevented. Therefore, it is possible to secure a stable contact resistance of the connection portion, reduce conduction failure, facilitate detection of a weak current, and prevent an erroneous determination in an ignition monitor using a change in a secondary-side weak current. it can.
Thus, a desired high voltage can be applied to the spark plug 110.

(Seventh Embodiment) FIG. 7 shows a main part of an engine ignition coil according to a seventh embodiment of the present invention. Components that are substantially the same as those of the sixth embodiment shown in FIG.

In the seventh embodiment, as shown in FIG. 7, a rubber plug cap 19 is fitted to the end of the case 15 on the high voltage side. It has an inner peripheral portion 19a having the same shape as the insulator outer peripheral portion 140a as a portion. That is, the insulator outer peripheral portion 140a of the ignition plug 140 and the plug cap 19
Has a straight shape with the inner peripheral portion 19a, and is in contact in the warp direction with the elasticity of the plug cap. Plug cap 1
By inserting the spark plug 140 into one end of the plug 9, the outer peripheral portion 140 a of the insulator of the spark plug 140 and the inner peripheral portion 19 a of the plug cap 19 are fitted, and a spring 47 as an elastic member is not shown. The high voltage side of the next coil and the spark plug 140 are electrically connected.

In the seventh embodiment, the contact between the inner peripheral portion 19a of the plug cap 19 and the outer peripheral portion 140a of the spark plug 140 is strengthened by tightening the plug cap with the coil side terminal 141 in the longitudinal direction. Therefore, the fitting force between the plug cap 19 and the spark plug 140 increases. 6 is reduced by the vibration of the engine, and the spring 47 and the high-voltage terminal 49 are reduced.
In addition, it is possible to prevent poor contact at the connection portion between the ignition plug 140 and the coil-side terminal 141. Therefore, it is possible to secure a stable contact resistance of the connection portion, reduce conduction failure, facilitate detection of a weak current, and prevent an erroneous determination in an ignition monitor using a change in a secondary-side weak current. it can. Thus, a desired high voltage can be applied to the ignition plug 140.

(Eighth Embodiment) FIG. 8 shows a main part of an ignition coil for an engine according to an eighth embodiment of the present invention. In the eighth embodiment, as shown in FIG. 8, the case 21 is formed of an insulating resin material into a cylindrical shape and houses a spring 52. The spring 52 has one end 52a connected to a high voltage terminal 51 that is electrically connected to the high voltage side of the secondary coil.
Is press-fitted in the radial direction, and the other end 52b is press-fitted in the coil-side terminal 151 of the ignition plug 150 in the radial direction. Thus, the spring 52 electrically connects the high-voltage terminal 51 and the ignition plug 150. A rubber plug cap 22 is fitted to the high-voltage end of the case 21. The plug cap 22 is connected to one end 52 of a spring.
a and the other end 52b are tightened by the tension F
a. When the ignition plug 150 is inserted into one end of the plug cap 22, the spring 52 as an elastic member electrically connects the high voltage side of the secondary coil (not shown) to the ignition plug 150.

In the eighth embodiment having the above structure, the spring 5
2 has one end 52a and the other end 52b
Further, since it is radially press-fitted into the coil side terminal 151 of the ignition plug 150 and tightened by the inner peripheral portion 22a of the plug cap 22 with the tightening force F, a stable contact resistance of the plug connection can be secured, and the engine The connection between the spring 52 and the high-voltage terminal 51 and the coil-side terminal 151 of the ignition plug 150 can be prevented from being rubbed. Therefore, abrasion of the connection between the spring 52 and the high-voltage terminal 51 and the ignition plug 150 can be reduced.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of the weak current, and to perform the ignition utilizing the change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the ignition plug 150.

Ninth Embodiment FIG. 9 shows a main part of an engine ignition coil according to a ninth embodiment of the present invention. Components that are substantially the same as in the eighth embodiment shown in FIG.

In the ninth embodiment, as shown in FIGS. 9A and 9B, the case 21 is formed in a cylindrical shape from an insulating resin material and accommodates a spring 54. The high voltage terminal 53 is electrically connected to the high voltage side of the secondary coil (not shown), and the mandrel 5 extends to the high voltage side end.
3a. One end 54a of the spring 54 is radially press-fitted into the mandrel 53a of the high-voltage terminal 53, and the other end 54b is radially press-fitted into the coil-side terminal 151 of the ignition plug 150. Thus, the spring 54 electrically connects the high-voltage terminal 53 and the ignition plug 150. A loose gap is formed between the outer wall of the shaft 53 a of the high-voltage terminal 53 and the center of the spring 54. When the coil side terminal 151 of the ignition plug 150 is press-fitted into the other end 54b of the spring 54, the spring 54 as an elastic member electrically connects the high voltage side of the secondary coil and the ignition plug 150.

In the ninth embodiment having the above structure, the spring 5
4 has one end 54a and the other end 54b
Mandrel 53a and coil side terminal 1 of spark plug 150
Since it is press-fitted in the radial direction into the plug 51, a stable contact resistance of the plug connection can be secured, and the connection between the spring 54 and the high-voltage terminal 53 and the coil side terminal 151 of the ignition plug 150 is rubbed by the engine vibration. Can be prevented. Therefore, it is possible to reduce the wear of the connection between the spring 54 and the high-voltage terminal 53 and the ignition plug 150.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to use an ignition utilizing a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the ignition plug 150.

(Tenth Embodiment) FIG. 10 shows a main part of an engine ignition coil according to a tenth embodiment of the present invention.
The same components as those in the eighth embodiment shown in FIG.

In the tenth embodiment, as shown in FIGS. 10A and 10B, the case 21 is formed in a cylindrical shape from an insulating resin material and accommodates a conductive rubber 55. The conductive rubber 55 is electrically connected to a high voltage side of a secondary coil (not shown). Also, the conductive rubber 55
Has an inner wall 55a that can be fitted to the coil side terminal 151 as an electrical connection part of the ignition plug 150. By fitting the coil side terminal 151 of the ignition plug 150 to the inner wall 55a of the conductive rubber 55, the conductive rubber 55 electrically connects the high voltage side of the secondary coil and the ignition plug 150.

In the tenth embodiment having the above structure, the coil side terminal 151 of the ignition plug 150 is connected to the inner wall 5 of the conductive rubber 55.
5a, a stable contact resistance of the plug connection can be ensured, and the high voltage side of the secondary coil and the coil side terminal 151 of the ignition plug 150 are prevented from being rubbed by engine vibration. be able to. Therefore, wear on the high voltage side of the secondary coil and the coil side terminal 151 of the ignition plug 150 can be reduced.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to perform ignition using a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the ignition plug 150.

(Eleventh Embodiment) FIG. 11 shows a main part of an engine ignition coil according to an eleventh embodiment of the present invention.
In the eleventh embodiment, as shown in FIG. 11, the case 23 is formed in a cylindrical shape from an insulating resin material, and houses a spring 54. The case 23 has a rib 23a as a protruding portion on the outer periphery, and the rib 23a can abut on an inner wall 200 of a plug hole formed in the engine block. The high-voltage terminal 53 is insert-molded in the case 23 and is electrically connected to a high-voltage side of a secondary coil (not shown). One end 54 a of the spring 54 as an elastic member is electrically connected to the high-voltage terminal 53. A rubber plug cap 24 is fitted to the high voltage side end of the case 23. Plug cap 24
The other end 54b of the spring 54 is connected to the ignition plug 160 by inserting the ignition plug 160 into one end of the ignition plug 160.
The spring 54 electrically connects the high-voltage side of the secondary coil and the ignition plug 160.

In the eleventh embodiment having the above-described structure, the ribs 23a which can be brought into contact with the inner wall 200 of the plug hole of the engine are provided on the outer periphery of the case 23.
The radial vibration of the connection between the one end 54a of the spring 54 and the high-voltage terminal 53 and the connection between the other end 54b of the spring 54 and the coil-side terminal 161 of the ignition plug 160 is reduced. Therefore, the spring 54
The connection between the high-voltage terminal 53 and the coil-side terminal 161 of the ignition plug 160 can be prevented from being rubbed, and wear can be reduced.

Further, by reducing the wear of the connection portion, it is possible to prevent the conduction of a weak current such as an ionic current from being hindered, to facilitate the detection of a weak current, and to make use of the secondary-side weak current change. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the ignition plug 160.

(Twelfth Embodiment) FIG. 12 shows a main part of an engine ignition coil according to a twelfth embodiment of the present invention.
Components that are substantially the same as in the eleventh embodiment shown in FIG.

In the twelfth embodiment, as shown in FIG. 12, the case 25 is formed of an insulating resin material into a cylindrical shape and houses a spring 54. The high-voltage terminal 53 is insert-molded in the case 25 and is electrically connected to a high-voltage side of a secondary coil (not shown). One end 54 a of the spring 54 as an elastic member is electrically connected to the high-voltage terminal 53. A rubber plug cap 26 is fitted to the high-voltage end of the case 25. The plug cap 26 is provided with a rib 2
6a, and the rib 26a can contact the inner wall 200 of the plug hole formed in the engine block. In one end of the plug cap 26, a spark plug 1
The other end 5 of the spring 54 is
Since 4b is electrically connected to the coil side terminal 161 of the ignition plug 160, the spring 54 electrically connects the high voltage side of the secondary coil and the ignition plug 160.

In the twelfth embodiment having the above-described structure, the rib 26a capable of contacting the inner wall 200 of the plug hole of the engine is provided on the outer periphery of the plug cap 26. The vibration in the radial direction of the connection portion and the connection portion between the other end 54b of the spring 54 and the coil side terminal 161 of the ignition plug 160 are reduced. Therefore, the spring 54, the high voltage terminal 53 and the spark plug 16
It is possible to prevent rubbing of the connection part with the zero coil side terminal 161 and reduce wear.

Further, by reducing the abrasion of the connection portion, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, to facilitate the detection of a weak current, and to perform ignition using a change in the secondary-side weak current. An erroneous determination on the monitor can be prevented. Thus, a desired high voltage can be applied to the ignition plug 160.

(Thirteenth Embodiment) FIG. 13 shows a main part of an engine ignition coil according to a thirteenth embodiment of the present invention.
In the thirteenth embodiment, as shown in FIG. 13, the case 27 is formed in a cylindrical shape from an insulating resin material, and an O-ring 29 as an annular member is fitted around the outer periphery of the case 27. The O-ring 29 can contact an inner wall of a plug hole formed in an engine block (not shown).

In the thirteenth embodiment having the above structure, the O-ring 29 which can be in contact with the inner wall of the plug hole of the engine is provided on the outer periphery of the case 27. Is alleviated. Therefore, it is possible to prevent the connection portion with the ignition plug 160 from being rubbed by the vibration of the engine, and to reduce wear.

Further, by reducing the wear of the connection portion with the ignition plug 160, it is possible to prevent the conduction of the weak current such as the ion current from being hindered, to facilitate the detection of the weak current, and to reduce the change in the secondary-side weak current. Can be prevented from being erroneously determined in an ignition monitor utilizing the above. Thus, a desired high voltage can be applied to the ignition plug 160.

(Fourteenth Embodiment) FIG. 14 shows a main part of an engine ignition coil according to a fourteenth embodiment of the present invention.
In the fourteenth embodiment, as shown in FIG. 14, the case 31 is formed in a cylindrical shape from an insulating resin material and houses a spring 32. The case 31 has an outer peripheral portion 31a and an inner peripheral portion 31b at an end on the high voltage side. The outer peripheral portion 31a as a seal portion can be in close contact with the outer periphery of the nut 172 of the ignition plug 170. One end of the spring 32 is electrically connected to a high voltage side of a secondary coil (not shown). The nut 172 of the spark plug 170 is inserted into the outer peripheral portion 31a of the case 31 so that the spring 32
Is electrically connected to the coil side terminal 171 of the ignition plug 170, so that the spring 32 electrically connects the high voltage side of the secondary coil to the ignition plug 170.

In the fourteenth embodiment having the above structure, the outer peripheral portion 31a which is in close contact with the nut 172 of the ignition plug 170 and seals the coil side terminal 171 of the ignition plug 170 has the case
1 is provided at the high voltage side end, so that the degree of adhesion of the plug connection part can be improved, and water can be prevented from entering the plug connection part.

Also, by eliminating the plug cap,
The physical size can be reduced, the number of parts can be reduced, the number of assembly steps can be reduced, and the manufacturing cost can be reduced. (Fifteenth Embodiment) FIG. 15 shows a main part of an engine ignition coil according to a fifteenth embodiment of the present invention. Components that are substantially the same as those in the fourteenth embodiment shown in FIG.

In the fifteenth embodiment, as shown in FIG. 15, a cylindrical member 173 is provided between a nut 172 of an ignition plug 170 and an insulator 174. The outer peripheral portion 31a as a seal portion can be in close contact with the outer periphery of the cylindrical member 173, and the inner peripheral portion 31b as the seal portion is
0 can be in close contact with the outer periphery of the insulator 174. The cylindrical member 173 and the insulator 174 are fitted into the outer peripheral portion 31a and the inner peripheral portion 31b of the case 31, so that the spring 32 is
Is electrically connected to the coil side terminal 171 of the ignition plug 170, so that the spring 32 electrically connects the high voltage side of the secondary coil to the ignition plug 170.

In the fourteenth embodiment having the above structure, the cylindrical member 1
The outer peripheral portion 31a and the inner peripheral portion 31b that are in close contact with the insulator 73 and the insulator 174 and seal the coil side terminal 171 of the ignition plug 170 are provided at the high voltage side end of the case 31. Thus, it is possible to prevent water from entering the plug connection portion.

Also, by eliminating the plug cap,
The physical size can be reduced, the number of parts can be reduced, the number of assembly steps can be reduced, and the manufacturing cost can be reduced.

(Sixteenth Embodiment) FIG. 16 shows a main part of an engine ignition coil according to a sixteenth embodiment of the present invention.
In the sixteenth embodiment, as shown in FIG. 16, the case 33 is formed in a cylindrical shape from an insulating resin material.
The high voltage terminal 35 is insert-molded in the case 33 and is electrically connected to a high voltage side of a secondary coil (not shown). On the inner wall of the high-voltage terminal 35, a female screw part 3 as a coupling part that can be screw-coupled to a male screw part 191 a provided on the outer wall of the coil side terminal 191 of the ignition plug 190.
5a is provided. A rubber plug cap 34 is fitted to the high voltage side end of the case 33. When the ignition plug 190 is inserted into one end of the plug cap 34 and the ignition coil is rotated, the high-voltage terminal 35 is screw-connected and electrically connected to the coil-side terminal 191 of the ignition plug 190. The portion 191a and the female screw portion 35a are connected to the high voltage side of the secondary coil and the spark plug 1
90 is electrically connected.

In the sixteenth embodiment having the above structure, the high-voltage terminal 35 is screw-connected to the coil-side terminal 191 of the ignition plug 190, so that a reliable connection unaffected by engine vibration can be obtained. Vibration is reduced. Therefore, it is possible to prevent the connection portion with the ignition plug 190 from being rubbed by the vibration of the engine, and to reduce wear. Therefore, it is possible to prevent the conduction of a weak current such as an ion current from being hindered, facilitate the detection of a weak current, and prevent an erroneous determination in an ignition monitor using a change in the secondary-side weak current. Thus, a desired high voltage can be applied to the ignition plug 190.

Further, since a spring for electrically connecting the high-voltage terminal 35 to the ignition plug 190 and a mounting flange for mounting the ignition coil to the engine can be eliminated, the physical size can be reduced.
The number of parts can be reduced, the number of assembly steps can be reduced, and the manufacturing cost can be reduced.

Seventeenth Embodiment FIG. 17 shows a main part of an engine ignition coil according to a seventeenth embodiment of the present invention.
In the seventeenth embodiment, as shown in FIG.
The high voltage terminal 61 is electrically connected to a high voltage side 63 of a secondary coil (not shown) via a spring 62. For this reason, at the time of assembly, it is possible to prevent the high pressure terminal 61 from being scraped by the spring load of the spring 62,
Insulation failure inside the coil due to shavings can be prevented.

Next, a first modification of the seventeenth embodiment is shown in FIG.
It is shown in (B). In the first modification, as shown in FIG. 17B, the high voltage terminal 64 is electrically connected to the high voltage side of the secondary coil (not shown) via the spring 67 and the intermediate member 65. High pressure terminal 6
4 has a tapered surface 64a, and the intermediate member 65 has a tapered surface 65a that can contact the tapered surface 64a of the high voltage terminal 64. Therefore, at the time of assembly, the tapered surface 64a of the high-voltage terminal 64 and the tapered surface 6
The contact pressure (frictional force) with 5a does not last for the tolerance absorption in the vertical direction in FIG. 17 (B), and can be set to the maximum pressure at the end of press-fitting. Can prevent insulation failure inside the coil.

Next, a second modification of the seventeenth embodiment will be described with reference to FIG.
It is shown in (C). In the second modification, as shown in FIG. 17C, the high voltage terminal 71 is electrically connected to a high voltage side of a secondary coil (not shown) via a spring 73 and an intermediate member 72. The intermediate member 72 has a tapered surface 72a that can contact the high-voltage terminal 71. For this reason, at the time of assembly, the contact pressure (frictional force) between the high-voltage terminal 71 and the tapered surface 72a of the intermediate member 72 is as shown in FIG.
7 (C) does not last for the tolerance absorption in the vertical direction, the pressure can be maximized at the end of press-fitting, the high-voltage terminal 71 can be prevented from being scraped, and the insulation failure inside the coil due to shavings can be prevented. it can.

(Eighteenth Embodiment) FIG. 18 shows a main part of an engine ignition coil according to an eighteenth embodiment of the present invention.
In the eighteenth embodiment, as shown in FIG.
The high voltage terminal 74 is electrically connected to a high voltage side 79 of a secondary coil (not shown) via an intermediate member 75. The intermediate member 75 has an annular protrusion 75a that can contact the high-voltage terminal 74. For this reason, during assembly,
The contact pressure (frictional force) between the high-voltage terminal 74 and the annular projection 75a of the intermediate member 75 does not last for the tolerance absorption in the vertical direction in FIG.
It is possible to prevent the high-voltage terminal 74 from being scraped, and prevent poor insulation inside the coil due to shaving powder.

Next, a first modification of the eighteenth embodiment is shown in FIG.
It is shown in (B). In the first modification, as shown in FIG. 18B, the high voltage terminal 76 is electrically connected to a high voltage side 79 of a secondary coil (not shown) via an intermediate member 77. High pressure terminal 76 is an intermediate member 77
Has an annular projection 76a that can abut against it. For this reason,
At the time of assembling, the contact pressure (frictional force) between the annular projection 76a of the high-voltage terminal 76 and the intermediate member 77 does not last for the tolerance absorption in the vertical direction in FIG. To prevent the high pressure terminal 76 from being scraped,
Insulation failure inside the coil due to shavings can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of an ignition coil for an engine according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a main part of an ignition coil for an engine according to a second embodiment of the present invention.

3A is a cross-sectional view showing a main part of an engine ignition coil according to a third embodiment of the present invention, and FIG. 3B is a view taken in the direction of arrow B in FIG.

FIG. 4 is a sectional view showing a main part of an engine ignition coil according to a fourth embodiment of the present invention.

FIGS. 5A and 5B are cross-sectional views showing a main part of an engine ignition coil according to a fifth embodiment of the present invention, wherein FIG. 5A is before a spark plug is inserted, and FIG. It is.

FIG. 6 is a sectional view showing a main part of an ignition coil for an engine according to a sixth embodiment of the present invention.

FIG. 7 is a sectional view showing a main part of an engine ignition coil according to a seventh embodiment of the present invention.

FIG. 8 is a sectional view showing a main part of an ignition coil for an engine according to an eighth embodiment of the present invention.

9A is a sectional view showing a main part of an engine ignition coil according to a ninth embodiment of the present invention, and FIG. 9B is an enlarged view of a part B of FIG. 9A.

FIG. 10A is a sectional view showing a main part of an engine ignition coil according to a tenth embodiment of the present invention, and FIG.
3 is a partially enlarged view of FIG.

FIG. 11 is a sectional view showing a main part of an ignition coil for an engine according to an eleventh embodiment of the present invention.

FIG. 12 is a sectional view showing a main part of an ignition coil for an engine according to a twelfth embodiment of the present invention.

FIG. 13 is a front view showing a main part of an engine ignition coil according to a thirteenth embodiment of the present invention.

FIG. 14 is a sectional view showing a main part of an ignition coil for an engine according to a fourteenth embodiment of the present invention.

FIG. 15 is a sectional view showing a main part of an engine ignition coil according to a fifteenth embodiment of the present invention.

FIG. 16 is a sectional view showing a main part of an engine ignition coil according to a sixteenth embodiment of the present invention.

17A is a sectional view showing a main part of an engine ignition coil according to a seventeenth embodiment of the present invention, and FIG.
Is a modified example 1 of (A), and (C) is a modified example 2 of (A).
It is.

FIG. 18A is a sectional view showing a main part of an engine ignition coil according to an eighteenth embodiment of the present invention, and FIG.
Is a modified example 1 of (A).

FIG. 19 is a cross-sectional view showing a main part of an engine ignition coil according to the related art.

[Explanation of symbols]

10 Ignition coil 11, 13, 15, 21, 23, 25, 27, 31, 3
3 Cases 12, 14, 16, 17, 19, 22, 24, 26, 3
4 Plug cap 29 O-ring (annular member) 32 Spring (elastic member) 35 High-voltage terminal 41, 43, 45, 49, 51, 53 High-voltage terminal 42, 44, 47, 52, 54 Spring (elastic member) 46 Wire rod terminal 50 Thin leaf spring (elastic member) 55 Conductive rubber 110, 120, 130, 140, 150, 160, 1
70, 190 Spark plug

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) H01F 31/00 501F (72) Inventor Koji 1-1-1, Showa-cho, Kariya-shi, Aichi Pref. DENSO Corporation (72) Inventor Junichi Wada 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside DENSO Corporation (72) Inventor Kazuhide Kawai 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside DENSO Corporation (72) Inventor Masafuto Sano 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside DENSO Corporation (72) Inventor Yoshihiro Shimoide 1-1-1, Showa-cho, Kariya-shi, Aichi Prefecture Inside DENSO Corporation (72) Inventor Ichiyo Osuga Aichi Prefecture 1-1-1, Showa-cho, Kariya F-term (reference) in Denso Corporation 3G019 KA14 KA23 KB09 KC05 KC07

Claims (18)

[Claims] 1. A stick-shaped ignition coil for generating a high voltage applied to an ignition plug of an internal combustion engine, wherein a primary coil and a secondary coil are electrically connected to one end of a high voltage side of the secondary coil. An elastic member that contacts and compresses the other end of the ignition plug when the ignition plug is inserted and electrically connects the high-voltage side of the secondary coil to the ignition plug; And an elastic member having an elastic force at a central portion larger than elastic forces at both end portions. 2. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, wherein a primary coil and a secondary coil are electrically connected to a high voltage side and one end of the secondary coil. A spring that electrically connects the high voltage side of the secondary coil and the ignition plug with each other, wherein the ignition plug and the other end are in contact with each other and compressed by the insertion of the ignition plug, A spring having a winding diameter at a center portion larger than a winding diameter at both end portions. 3. A stick-shaped ignition coil for generating a high voltage applied to a spark plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a high voltage electrically connected to a high voltage side of the secondary coil. One end is electrically connected to the high-voltage terminal, and the other end of the ignition plug comes into contact with the other end of the ignition plug and is compressed when the ignition plug is inserted. And an elastic member for electrically connecting the plug to the ignition coil, wherein one or both of the ignition coil and the high voltage terminal has a groove in which the elastic member can be fitted. 4. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil, electrically connected to a high voltage side of the secondary coil; A high-voltage terminal having a first groove, electrically connected to an inner wall of the first groove, and contacting the ignition plug when the ignition plug is inserted thereinto; And a wire terminal for electrically connecting the ignition plug to the ignition plug.
An ignition coil for an internal combustion engine, comprising: 5. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. A plug cap in which the ignition plug is inserted into one end and has a fitting portion at the other end for fitting to the high voltage side end of the case; and a high voltage side and one end of the secondary coil. Are electrically connected, and the other end of the spark plug comes into contact with the plug and is compressed when the spark plug is inserted into the plug cap,
An elastic member that electrically connects the high voltage side of the secondary coil and the ignition plug; and a covering member that is provided on an outer periphery of the plug cap and suppresses radial expansion of the plug cap. An ignition coil for an internal combustion engine. 6. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. A plug cap in which the ignition plug is inserted into one end and has a fitting portion at the other end for fitting to the high voltage side end of the case; and a high voltage side and one end of the secondary coil. Are electrically connected, and the other end of the spark plug comes into contact with the plug and is compressed when the spark plug is inserted into the plug cap,
An elastic member that electrically connects the high voltage side of the secondary coil and the ignition plug; and a covering member that extends from the case to the high voltage side and covers an outer periphery of the plug cap. An ignition coil for an internal combustion engine. 7. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. The ignition plug is electrically connected to the high voltage side of the secondary coil, and is contacted with the ignition plug at a plurality of contact portions when the ignition plug is inserted, so that the high voltage side of the secondary coil and the ignition An ignition coil for an internal combustion engine, comprising: an elastic member that electrically connects a plug; and a tapered surface provided in the case and forming an inner wall surface of a housing chamber that houses the elastic member. 8. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. The high voltage side and one end of the secondary coil are electrically connected, and the ignition plug and the other end are in contact with each other and compressed when the ignition plug is inserted, and the high voltage side of the secondary coil is And an elastic member for electrically connecting the ignition plug to the ignition plug, wherein the other end of the elastic member has a larger inner diameter than a tip of the ignition plug before the ignition plug is inserted. Ignition coil for an internal combustion engine. 9. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. A plug cap into which the ignition plug is inserted into one end and a high voltage side end of the case is inserted into the other end; and a high voltage side and one end of the secondary coil are electrically connected. The spark plug is connected to the plug cap and the other end thereof is brought into contact with the spark plug when the spark plug is fitted and compressed,
An elastic member for electrically connecting the high voltage side of the secondary coil to the ignition plug; an inner wall provided on an inner periphery of the plug cap and having the same shape as an outer periphery of a fitting portion of the ignition plug An ignition coil for an internal combustion engine, comprising: 10. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. A plug cap into which the ignition plug is inserted into one end and a high voltage side end of the case is inserted into the other end; and a high voltage side and one end of the secondary coil are electrically connected. The ignition plug is connected to the plug cap, and the other end of the ignition plug comes into contact with the ignition plug when the ignition plug is fitted into the plug cap.
An elastic member for electrically connecting the high voltage side of the secondary coil to the spark plug; and means provided on an inner wall of the plug cap for fastening an electric connection portion of the elastic member in a transverse direction. An ignition coil for an internal combustion engine. 11. A stick-shaped ignition coil for generating a high voltage applied to a spark plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a high voltage electrically connected to a high voltage side of the secondary coil. One end is radially pressed into the high-voltage terminal, and the other end is radially pressed into the ignition plug by fitting the ignition plug, and the high voltage side of the secondary coil and the ignition plug And an elastic member that electrically connects the ignition coil and the ignition coil. 12. A stick-shaped ignition coil for generating a high voltage applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil, electrically connected to a high voltage side of the secondary coil; A conductive rubber that is fitted with the electrical connection portion of the ignition plug by being fitted with the ignition plug, and electrically connects the high voltage side of the secondary coil to the ignition plug. An ignition coil for an internal combustion engine. 13. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. A plug cap into which the spark plug is inserted into one end and a high-voltage side end of the case fits into the other end; and a high-voltage side of the secondary coil and one end are electrically connected. When the spark plug is inserted into the plug cap, the other end of the spark plug comes into contact with the spark plug and is compressed,
An elastic member for electrically connecting the high voltage side of the secondary coil to the ignition plug; and a protrusion provided on an outer periphery of the case and capable of abutting against an inner wall of a plug hole of the internal combustion engine. An ignition coil for an internal combustion engine, comprising: 14. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. A plug cap into which the spark plug is inserted into one end and a high-voltage side end of the case fits into the other end; and a high-voltage side of the secondary coil and one end are electrically connected. When the spark plug is inserted into the plug cap, the other end of the spark plug comes into contact with the spark plug and is compressed,
An elastic member for electrically connecting the high voltage side of the secondary coil to the ignition plug; and a protrusion provided on the outer periphery of the plug cap and capable of contacting an inner wall of a plug hole of the internal combustion engine. An ignition coil for an internal combustion engine. 15. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. An ignition coil for an internal combustion engine, comprising: an annular member provided on an outer periphery of the case and capable of contacting an inner wall of a plug hole of the internal combustion engine. 16. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. A sealing portion provided at a high-voltage end of the case and in close contact with the ignition plug to seal an electrical connection portion of the ignition plug. 17. A stick-shaped ignition coil for generating a high voltage to be applied to a spark plug of an internal combustion engine, wherein the primary coil and the secondary coil are electrically connected to a high voltage side of the secondary coil. A connection portion that is connected to the electrical connection portion of the ignition plug by being fitted with the ignition plug, and that electrically connects the high voltage side of the secondary coil to the ignition plug. Ignition coil for internal combustion engines. 18. A stick-shaped ignition coil for generating a high voltage to be applied to an ignition plug of an internal combustion engine, comprising: a primary coil and a secondary coil; and a cylindrical case accommodating the primary coil and the secondary coil. A plug cap into which the ignition plug is inserted into one end, and a plug cap into which the high-voltage side end of the case fits into the other end; and electrically connected to the high-voltage side of the secondary coil, A screw portion for fitting the ignition plug into the plug cap and rotating to couple with the electrical connection portion of the ignition plug and electrically connect the high voltage side of the secondary coil to the ignition plug. An ignition coil for an internal combustion engine, comprising: