JP6958087B2 - Ignition coil and connection structure between ignition coil and spark plug - Google Patents

Description

The present invention relates to a connection structure for connecting an ignition coil and a spark plug.

Conventionally, there is a connection structure in which a terminal portion of a spark plug having a male screw formed and a cylindrical high-voltage terminal of an ignition coil are connected by a U-shaped clip spring (see Patent Document 1). In the connection structure described in Patent Document 1, two notch holes arranged in the axial direction are formed on the outer peripheral portion of the high voltage terminal, and two clip springs fitted to the outer peripheral portion of the high voltage terminal are notched respectively. It is engaged with the terminal portion of the spark plug through the hole.

JP-A-2009-167978

By the way, in the connection structure described in Patent Document 1, two notch holes are formed at the same position and the same shape in the circumferential direction of the high voltage terminal, and two clip springs are formed from the same direction in the radial direction of the high voltage terminal. It is fitted in the notch hole of the high voltage terminal.

Therefore, the terminal portion of the spark plug is pushed in the same radial direction (first direction) by the two clip springs, and the terminal portion is pushed from the radial direction (second direction) perpendicular to the pressed radial direction. No force is working. Therefore, when the ignition coil and the spark plug vibrate in the first direction, the force of the clip spring pushing the terminal portion suppresses the vibration of the ignition coil due to the vibration of the terminal portion of the spark plug. However, when the ignition coil and the spark plug vibrate in the second direction, only a frictional force acts between the clip spring and the terminal portion, and not only the vibration of the ignition coil is difficult to be suppressed, but also the clip spring is worn. There is a risk of breaking.

The present invention has been made to solve the above problems, and a main object thereof is to provide an ignition coil capable of suppressing the vibration of the ignition coil regardless of the direction in which the ignition coil and the spark plug vibrate. There is.

The first means for solving the above problems is
High-voltage terminals (30, 130) having a cylindrical portion (33, 133) formed in a cylindrical shape and connected to a secondary coil (21).
An ignition coil (10) including a plurality of clip springs (40A, 40B) fitted to the outer peripheral portion of the tubular portion.
A plurality of notches (34A, 34B) arranged in the axial direction are formed at the same position in the circumferential direction on the outer peripheral portion of the tubular portion.
The plurality of clip springs include clip springs that are fitted into the notch holes of the tubular portion from opposite directions in the radial direction of the tubular portion.

According to the above configuration, in the ignition coil, the high voltage terminal has a cylindrical portion formed in a cylindrical shape and is connected to the secondary coil. The plurality of clip springs are fitted to the outer peripheral portion of the tubular portion.

A plurality of notch holes arranged in the axial direction are formed on the outer peripheral portion of the tubular portion. The plurality of clip springs include clip springs fitted in the notch holes of the tubular portion, respectively. Therefore, by inserting the terminal portion of the spark plug into the cylindrical portion, a plurality of clip springs are formed in the outer peripheral portion of the terminal portion via the plurality of notch holes (for example, a valley portion of a male screw). , The valley of the step, the taper) can be engaged with each other. Therefore, the high voltage terminal of the ignition coil and the terminal portion of the spark plug can be made conductive, and the ignition coil and the spark plug can be connected.

Here, the plurality of notch holes arranged in the axial direction of the tubular portion are formed at the same position in the circumferential direction of the tubular portion. Therefore, when a plurality of clip springs are fitted into the notch holes of the high voltage terminals from the same direction in the radial direction of the tubular portion, the terminal portion of the spark plug is inserted into the tubular portion. In, the terminal portion of the spark plug is pushed in the same radial direction (first direction) by a plurality of clip springs, and a force that pushes the terminal portion from the radial direction (second direction) perpendicular to the pressed radial direction acts. do not.

On the other hand, the plurality of clip springs include clip springs that are fitted into the notch holes of the tubular portion from opposite directions in the radial direction of the tubular portion. Therefore, there are clip springs that push the terminal portions in different radial directions, and in the radial direction (second direction) perpendicular to the radial direction (first direction) in which one clip spring pushes the terminal portion. A component of the force that pushes the terminal is generated. Therefore, when the ignition coil and the spark plug vibrate not only in the first direction but also in the second direction, the force of the clip spring pushing the terminal portion suppresses the vibration of the ignition coil due to the vibration of the terminal portion. can do. As a result, the vibration of the ignition coil can be suppressed regardless of the direction in which the ignition coil and the spark plug vibrate.

Further, the plurality of notch holes are formed at the same position in the circumferential direction of the tubular portion. Therefore, when forming a plurality of notch holes in the tubular portion, processing can be performed in the same direction, and it is not necessary to adjust the processing direction (angle). As a result, the labor and cost of processing can be reduced. Further, the vibration of the ignition coil can be suppressed only by reversing the directions in which the plurality of clip springs are fitted into the notch holes of the tubular portion.

If the length of the notch hole in the circumferential direction of the tubular portion is too short, a plurality of clip springs are fitted into the notch hole of the tubular portion from opposite directions in the radial direction of the tubular portion. Even if it is included, a plurality of clip springs may push the terminal portion of the ignition plug in substantially the same radial direction.

In this respect, in the second means, the length of the notch hole in the circumferential direction of the tubular portion is set to be longer than the half circumference of the tubular portion. According to such a configuration, the clip springs that push the terminal portions in different radial directions are surely present, and the vibration of the ignition coil can be surely suppressed regardless of the direction in which the ignition coil and the spark plug vibrate. ..

When the length of the notch hole in the circumferential direction of the tubular portion is longer than the half circumference of the tubular portion, the length at which the clip spring fits into the outer peripheral portion of the tubular portion becomes shorter. In this case, the clip spring may rotate along the outer peripheral surface of the tubular portion before the terminal portion of the spark plug is inserted into the tubular portion.

In this regard, in the third means, the clip spring is provided with a detent to stop the clip spring from rotating along the outer peripheral surface of the cylindrical portion. According to such a configuration, even if the length of the notch hole in the circumferential direction of the tubular portion is longer than the half circumference of the tubular portion, the cylindrical portion is formed before the terminal portion of the spark plug is inserted into the tubular portion. It is possible to prevent the clip spring from rotating along the outer peripheral surface of the portion.

The fourth means is
High-voltage terminals (30, 130) having a cylindrical portion (33, 133) formed in a cylindrical shape and connected to a secondary coil (21).
An ignition coil (10) including a plurality of clip springs (40A, 40B) fitted to the outer peripheral portion of the tubular portion.
A plurality of notches (34A, 34B) arranged in the axial direction are formed on the outer peripheral portion of the tubular portion.
The plurality of notch holes include notches formed at different positions in the circumferential direction of the tubular portion.
The plurality of clip springs are ignition coils, each of which is fitted into the plurality of notch holes.

According to the above configuration, the plurality of notch holes arranged in the axial direction of the tubular portion include notches formed at different positions in the circumferential direction of the tubular portion. The plurality of clip springs are fitted into the plurality of notch holes, respectively. Therefore, there are clip springs that push the terminal portions inserted inside the tubular portion in different radial directions. Therefore, a component of the force that pushes the terminal portion in the radial direction (second direction) perpendicular to the radial direction (first direction) in which one clip spring pushes the terminal portion is generated. As a result, the vibration of the ignition coil can be suppressed regardless of the direction in which the ignition coil and the spark plug vibrate.

When the notch holes are formed at positions separated from each other by a predetermined angle in the circumferential direction of the tubular portion, the clip springs push the terminal portions of the spark plug from the radial directions forming the predetermined angles with each other.

In this regard, in the fifth means, the plurality of notch holes include notches formed at positions 90 ° apart from each other in the circumferential direction of the tubular portion. According to such a configuration, there are clip springs that push the terminal portions from the radial directions forming 90 ° with each other. Therefore, a force that the clip spring pushes the terminal portion in the radial direction (first direction) and a force that the clip spring pushes the terminal portion in the radial direction (second direction) perpendicular to the first direction act. Therefore, the vibration of the ignition coil can be effectively suppressed regardless of the direction in which the ignition coil and the spark plug vibrate.

The sixth means is a connection structure for connecting the ignition coil of any one of the first to fifth means and the spark plug (80).
The spark plug includes a terminal portion having a concave portion (88a, 188a) formed on the outer peripheral portion and inserted into the tubular portion.
The plurality of clip springs are respectively engaged with the recesses of the terminal portion via the plurality of notch holes.
The points of action of the plurality of clip springs engaged with the recesses to push the terminal portions include the points of action of pushing the terminal portions at different positions in the circumferential direction of the terminal portions.

According to the above configuration, the points of action in which the plurality of clip springs engaged with the recesses push the terminal parts, respectively, include the points of action in which the terminal parts are pushed at different positions in the circumferential direction of the terminal parts. That is, there are clip springs that push the terminal portions of the ignition plug in different radial directions, and the radial direction (second direction) perpendicular to the radial direction (first direction) in which one clip spring pushes the terminal portion. ) Has a component of the force that pushes the terminal part. Then, when the first to fifth means are premised, the same effects as those of the first to fifth means can be obtained.

The seventh means is
It is a connection structure that connects the ignition coil (10) and the spark plug (80).
The ignition coil is
High-voltage terminals (30, 130) having a cylindrical portion (33, 133) formed in a cylindrical shape and connected to a secondary coil (21).
A plurality of clip springs (40A, 40B) fitted to the outer peripheral portion of the tubular portion are provided, and the spark plug is inserted into the tubular portion with recesses (88a, 188a) formed in the outer peripheral portion. Equipped with a terminal section (80, 188)
A plurality of notches (34A, 34B) arranged in the axial direction are formed on the outer peripheral portion of the tubular portion.
The plurality of clip springs are respectively engaged with the recesses of the terminal portion via the plurality of notch holes.
The points of action of the plurality of clip springs engaged with the recesses to push the terminal portions include the points of action of pushing the terminal portions at different positions in the circumferential direction of the terminal portions.

According to the above configuration, the points of action in which the plurality of clip springs engaged with the recesses push the terminal parts, respectively, include the points of action in which the terminal parts are pushed at different positions in the circumferential direction of the terminal parts. That is, there are clip springs that push the terminal portions of the ignition plug in different radial directions, and the radial direction (second direction) perpendicular to the radial direction (first direction) in which one clip spring pushes the terminal portion. ) Has a component of the force that pushes the terminal part. Therefore, when the ignition coil and the spark plug vibrate not only in the first direction but also in the second direction, the force of the clip spring pushing the terminal portion suppresses the vibration of the ignition coil due to the vibration of the terminal portion. can do. As a result, the vibration of the ignition coil can be suppressed regardless of the direction in which the ignition coil and the spark plug vibrate.

Partial cross-sectional view showing an ignition coil and a spark plug. FIG. 5 is a cross-sectional view showing the ignition coil of FIG. The perspective view which shows the high voltage terminal and the clip spring of the prior art. The side view which shows the high voltage terminal and the clip spring of the prior art. FIG. 5 is a sectional view taken along line VV of FIG. A partial cross-sectional view showing a connection structure between a conventional ignition coil and a spark plug. FIG. 6 is a cross-sectional view taken along the line VII-VII of FIG. The cross-sectional view which shows the force acting on the terminal part from the clip spring of the prior art. FIG. 5 is a cross-sectional view showing the relationship between vibration and the force acting on the terminal portion from the clip spring of the prior art. The side view which shows the high voltage terminal and the clip spring of 1st Embodiment. FIG. 10 is a sectional view taken along line XI-XI of FIG. FIG. 10 is a cross-sectional view taken along the line XII-XII of FIG. The side view which shows an example of the high voltage terminal of 1st Embodiment. FIG. 13 is a cross-sectional view taken along the line XIV-XIV of FIG. The side view which shows the other example of the high voltage terminal of 1st Embodiment. FIG. 15 is a cross-sectional view taken along the line XVI-XVI of FIG. The plan view which shows the state before and after cutting of a clip spring. FIG. 3 is a partial cross-sectional view showing a connection structure between the ignition coil and the spark plug of the first embodiment. FIG. 18 is a sectional view taken along line XIX-XIX. FIG. 5 is a cross-sectional view showing an example of the relationship between the length of the notch hole and the point of action of the first embodiment. FIG. 5 is a cross-sectional view showing another example of the relationship between the length of the notch hole and the point of action of the first embodiment. FIG. 5 is a cross-sectional view showing an example of the force acting on the terminal portion from the clip spring of the first embodiment. FIG. 5 is a cross-sectional view showing another example of the force acting on the terminal portion from the clip spring of the first embodiment. The side view which shows an example of the high voltage terminal of 2nd Embodiment. FIG. 24 is a cross-sectional view taken along the line XXV-XXV of FIG. 24. The side view which shows the high voltage terminal and the clip spring of 2nd Embodiment. FIG. 26 is a cross-sectional view taken along the line XXVII-XXVII of FIG. FIG. 26 is a cross-sectional view taken along the line XXVIII-XXVIII of FIG. FIG. 3 is a partial cross-sectional view showing a connection structure between the ignition coil and the spark plug of the second embodiment. FIG. 29 is a cross-sectional view taken along the line XXX-XXX of FIG. FIG. 5 is a cross-sectional view showing an example of the force acting on the terminal portion from the clip spring of the second embodiment. FIG. 5 is a cross-sectional view showing another example of the force acting on the terminal portion from the clip spring of the second embodiment. The partial cross-sectional view which shows the modification example of the connection structure of an ignition coil and a spark plug.

(First Embodiment)
Hereinafter, the first embodiment embodied in the ignition coil and the spark plug used in the gasoline engine (internal combustion engine) of the two-wheeled vehicle will be described with reference to the drawings.

As shown in FIG. 1, the ignition coil 10 includes a primary coil 11, a secondary coil 21, a core 27, a secondary terminal 25, a high voltage terminal 30, clip springs 40A and 40B, a plug cap 70, a connector 73, and the like. ing. The spark plug 80 includes a housing 81, an insulator portion 83, a center electrode 85, a ground electrode 87, a terminal portion 88, and the like.

In the ignition coil 10, the core 27 is arranged on the inner peripheral side of the primary coil 11, and the secondary coil 21 is arranged on the outer peripheral side of the primary coil 11. Both ends of the winding of the primary coil 11 are connected to an external electric circuit via the connector 73.

The end of the winding of the secondary coil 21 on the high voltage side is connected to the secondary terminal 25. The secondary terminal 25 is formed in a columnar shape by a conductive material. The secondary terminal 25 is formed with a fitting hole 25a extending in the direction of the central axis at a predetermined depth.

The high voltage terminal 30 is made of a conductive material and includes a flange portion 31, a tubular portion 33, and a protruding portion 38. The flange portion 31 is formed in a disk shape (cylindrical shape). In the direction of the central axis of the flange portion 31, a cylindrical tubular portion 33 extends from one end, and a cylindrical protruding portion 38 extends from the other end. The protruding portion 38 is fitted in the fitting hole 25a of the secondary terminal 25, and the secondary terminal 25 and the high voltage terminal 30 are electrically connected to each other. Notch holes 34A and 34B, which will be described later, are formed on the outer peripheral portion of the tubular portion 33.

In the spark plug 80, the housing 81 is formed in a cylindrical shape by a conductive material. A male screw portion 82 is formed on the housing 81. A ground electrode 87 is connected to the tip of the housing 81. The male threaded portion 82 is fastened to the female threaded portion formed on the cylinder head of the engine.

A cylindrical insulator portion 83 is arranged on the inner peripheral side of the housing 81. A center electrode 85 is arranged on the inner peripheral side of the insulator portion 83. The center electrode 85 projects from the tip of the insulator portion 83 and faces the ground electrode 87. The center electrode 85 and the ground electrode 87 are insulated by an insulator portion 83.

The center electrode 85 is connected to the terminal portion 88 via a resistor or the like. The terminal portion 88 projects from the base end (end on the ignition coil 10 side) of the insulator portion 83. The terminal portion 88 is formed in a columnar shape, and a male screw 88a is formed on the outer peripheral portion. The terminal portion 88 is inserted inside the tubular portion 33 of the high voltage terminal 30.

Clip springs 40A and 40B, which will be described later, are fitted to the outer peripheral portion of the tubular portion 33 of the high voltage terminal 30. The clip springs 40A and 40B are engaged with the valleys (recesses) of the male threads 88a of the terminal portion 88 via the notch holes 34A and 34B, respectively. As a result, the high voltage terminal 30 of the ignition coil 10 and the terminal portion 88 of the spark plug 80 are made conductive, and the ignition coil 10 and the spark plug 80 are connected. The high-voltage terminal 30, the terminal portion 88, and the clip springs 40A and 40B constitute a connection structure between the ignition coil 10 and the spark plug 80. Further, the connection portion 15 of the ignition coil 10 and the insulator portion 83 of the spark plug 80 are also connected by the plug cap 70.

FIG. 2 is a cross-sectional view showing the ignition coil 10 of FIG. As shown in the figure, when the ignition coil 10 is not connected to the spark plug 80, the clip springs 40A and 40B are fitted into the outer peripheral portion of the tubular portion 33 of the high voltage terminal 30 and the notch holes 34A and 34B. ing.

FIG. 3 is a perspective view showing the high voltage terminal 30 and the clip springs 40A and 40B of the prior art. The same parts as those in the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

Notch holes 34A and 34B arranged in the axial direction are formed on the outer peripheral portion of the tubular portion 33. The distance between the notch hole 34A and the notch hole 34B in the axial direction is set to a multiple of the pitch of the male screw 88a of the terminal portion 88. The cutout holes 34A and 34B are formed in the same shape and extend in an arc shape along the circumferential direction of the tubular portion 33. The lengths of the cutout holes 34A and 34B in the circumferential direction of the tubular portion 33 are set shorter than the half circumference of the tubular portion 33. The length of the notch hole 34A and the length of the notch hole 34B are equal, and the width of the notch hole 34A and the width of the notch hole 34B are equal. The cutout holes 34A and 34B are formed at the same positions in the circumferential direction of the tubular portion 33. That is, the notch hole 34A and the notch hole 34B are formed in parallel.

The clip springs 40A and 40B are formed by bending a high-hardness spring material (wire material) such as a piano wire. The cross-sectional shape of the clip springs 40A and 40B is, for example, circular. The clip springs 40A and 40B have the same shape. The clip springs 40A and 40B are formed in a U shape, and include a holding portion 41 and a fitting portion 42. The holding portion 41 and the fitting portion 42 face each other. The holding portion 41 is formed in an arc shape and is fitted to the outer peripheral portion of the tubular portion 33. The curvature of the inner peripheral surface of the holding portion 41 is substantially equal to the curvature of the outer peripheral surface of the tubular portion 33. The fitting portion 42 is formed in a straight line, and is fitted into the notch holes 34A and 34B of the tubular portion 33, respectively.

FIG. 4 is a side view showing the high voltage terminal 30 and the clip springs 40A and 40B of the prior art, and FIG. 5 is a sectional view taken along line VV of FIG.

As shown in the figure, the holding portion 41 of the clip spring 40B is fitted to the outer peripheral portion of the tubular portion 33. The fitting portion 42 of the clip spring 40B is fitted into the notch hole 34B of the tubular portion 33. As a result, the clip spring 40B is restricted from moving in the axial direction of the tubular portion 33. The fitting portion 42 is in contact with two wall portions 35 corresponding to the extension of the notch hole 34A. As a result, the clip spring 40B is restricted from rotating in the circumferential direction of the tubular portion 33. Here, the clip spring 40B has been described as an example, but the same applies to the clip spring 40A.

FIG. 6 is a partial cross-sectional view showing a connection structure between the ignition coil 10 and the spark plug 80 of the prior art, and FIG. 7 is a VII-VII line discourse diagram of FIG.

When the terminal portion 88 of the spark plug 80 is inserted into the tubular portion 33, the clip springs 40A and 40B are pushed open by the terminal portion 88. At this time, as shown in FIG. 7, the clip spring 40B rotates in the rotation direction (clockwise in FIG. 7) continuing from the fitting portion 42 to the holding portion 41. However, the rotation of the clip spring 40B is restricted by the contact of the fitting portion 42 with the outer end portion 35a of the wall portion 35 on the connecting portion side between the fitting portion 42 and the holding portion 41.

Here, in the connection structure of the prior art, the notch holes 34A and 34B are formed at the same position and the same shape in the circumferential direction of the tubular portion 33. Then, the clip springs 40A and 40B are fitted into the notch holes 34A and 34B of the tubular portion 33 from the same direction, respectively. Therefore, as shown by the force F in FIG. 8, the terminal portion 88 of the spark plug 80 is pushed in the same radial direction (first direction) by the clip springs 40A and 40B (only the clip spring 40B is shown in the figure). Has been done. The force F acts in the radial direction of the terminal portion 88 in the direction perpendicular to the fitting portion 42. The force that pushes the terminal portion 88 from the radial direction (second direction) perpendicular to the force F, that is, the radial direction of the terminal portion 88 that is parallel to the fitting portion 42, does not act.

Therefore, as shown in FIG. 9, when the ignition coil 10 and the spark plug 80 vibrate in the X direction, the force F of the clip springs 40A and 40B pushing the terminal portion 88 causes the terminal portion 88 (spark plug 80) to vibrate. The vibration of the tubular portion 33 (high voltage terminal 30, ignition coil 10) is suppressed. However, when the ignition coil 10 and the spark plug 80 vibrate in the Y direction, only frictional force acts between the clip springs 40A and 40B and the terminal portion 88. Therefore, not only the vibration of the ignition coil 10 is difficult to be suppressed, but also the clip springs 40A and 40B may be worn and broken. That is, the clip springs 40A and 40B are worn due to the relative difference (relative movement) in vibration between the terminal portion 88 (spark plug 80) and the tubular portion 33 (high voltage terminal 30, ignition coil 10). Become.

Therefore, in the present embodiment, as shown in FIGS. 10 to 12, the clip springs 40A and 40B have notches 34A and 34B of the tubular portion 33 of the high voltage terminal 30 from opposite directions in the radial direction of the tubular portion 33. Are fitted to each. 11 is a sectional view taken along line XI-XI of FIG. 10, and FIG. 12 is a sectional view taken along line XII-XII of FIG. In the following, the differences from the prior art will be mainly described.

As shown in FIG. 11, the fitting portion 42 of the clip spring 40A is a wall portion 35 on the connecting portion side between the fitting portion 42 and the holding portion 41 among the two wall portions 35 corresponding to the extension of the notch hole 34A. It is in contact with the outer end portion 35a of the above. The clip spring 40A is provided with a detent 43, which will be described later, at the tip of the holding portion 41. The detent 43 is engaged with a wall portion 35 on the opposite side of the connecting portion between the fitting portion 42 and the holding portion 41. As a result, the clip spring 40A is restricted from rotating in the circumferential direction of the tubular portion 33.

As shown in FIG. 12, the clip spring 40B is fitted into the notch hole 34B of the tubular portion 33 from the direction opposite to that of the clip spring 40A. Other points are the same as the clip spring 40A.

FIG. 13 is a side view showing an example of the high voltage terminal 30 of the first embodiment. FIG. 14 is a cross-sectional view taken along the line XIV-XIV of FIG. In this example, the length of the notch hole 34B (34A) in the circumferential direction of the tubular portion 33 is set shorter than the half circumference of the tubular portion 33, as in the prior art shown in FIGS. 3 to 5.

FIG. 15 is a side view showing another example of the high voltage terminal 30 of the first embodiment. FIG. 16 is a cross-sectional view taken along the line XVI-XVI of FIG. In this example, unlike the prior art shown in FIGS. 3 to 5, the length of the notch hole 34B (34A) in the circumferential direction of the tubular portion 33 is set to be longer than the half circumference of the tubular portion 33.

FIG. 17 is a plan view showing a state before and after cutting of the clip spring 40A (40B) used for the high voltage terminal 30 of FIG. As shown in the figure, the clip spring 40A includes a cutting portion 44 extending from the fitting portion 42 and a cutting portion 45 extending from the holding portion 41 before cutting. Further, a rotation stopper 43 is formed at the connecting portion between the holding portion 41 and the cutting portion 45. The detent 43 projects inward from the inner peripheral surface of the arc-shaped holding portion 41. That is, the detent 43 is a portion of the arc-shaped holding portion 41 having a diameter smaller than that of the other portions.

The clip spring 40A (40B) is fitted into the outer peripheral portion of the tubular portion 33 of the high voltage terminal 30 and the notch hole 34A (34B) in a state where the cutting portions 44 and 45 are not cut. After that, the cutting portions 44 and 45 of the clip spring 40A (40B) are cut.

FIG. 18 is a partial cross-sectional view showing a connection structure between the ignition coil 10 and the spark plug 80 of the present embodiment. FIG. 19 is a cross-sectional view taken along the line XIX-XIX of FIG. In FIGS. 18 and 19, the high voltage terminals 30 of the examples shown in FIGS. 15 and 16 are used.

When the terminal portion 88 of the spark plug 80 is inserted into the tubular portion 33, the clip springs 40A and 40B are pushed open by the terminal portion 88. At this time, as shown in FIG. 19, the clip spring 40B rotates in the rotation direction (clockwise in FIG. 19) continuing from the fitting portion 42 to the holding portion 41. However, the rotation of the clip spring 40B is restricted by the contact of the fitting portion 42 with the outer end portion 35a of the wall portion 35 on the connecting portion side between the fitting portion 42 and the holding portion 41. On the other hand, the clip spring 40A rotates in the rotation direction (counterclockwise in FIG. 19) continuing from the fitting portion 42 to the holding portion 41. However, the rotation of the clip spring 40A is restricted by the contact of the fitting portion 42 with the outer end portion 35a of the wall portion 35 on the connecting portion side between the fitting portion 42 and the holding portion 41.

FIG. 20 is a cross-sectional view showing an example of the relationship between the lengths of the cutout holes 34A and 34B and the point of action of the present embodiment. In this example, as shown in FIGS. 13 and 14, the length of the notch hole 34B (34A) in the circumferential direction of the tubular portion 33 is set shorter than the half circumference of the tubular portion 33.

As shown in FIG. 20, the notch depth of the notch hole 34B (34A) is set to the depth L1. The fitting portions 42 of the clip springs 40A and 40B are in contact with the terminal portions 88 of the spark plug 80, respectively. Specifically, the fitting portion 42 is engaged with the valley portion (recess) of the male screw 88a of the terminal portion 88. Then, in the radial direction of the terminal portion 88 of the spark plug 80, the angle formed by the direction perpendicular to the fitting portion 42 of the clip spring 40A and the direction perpendicular to the fitting portion 42 of the clip spring 40B is an angle φ1. ing. The angle φ1 is an angle smaller than 90 °.

FIG. 21 is a cross-sectional view showing another example of the relationship between the length of the cutout holes 34A and 34B and the point of action of the present embodiment. In this example, as shown in FIGS. 15 and 16, the length of the notch hole 34B (34A) in the circumferential direction of the tubular portion 33 is set to be longer than the half circumference of the tubular portion 33.

As shown in FIG. 21, the notch depth of the notch hole 34B (34A) is set to the depth L2. The depth L2 is longer than the depth L1 in FIG. 20 (L1 <L2). Then, in the radial direction of the terminal portion 88 of the spark plug 80, the angle formed by the direction perpendicular to the fitting portion 42 of the clip spring 40A and the direction perpendicular to the fitting portion 42 of the clip spring 40B is an angle φ2. ing. The angle φ2 is larger than the angle φ1 and is 90 ° (φ1 <φ2 = 90 °).

FIG. 22 is a cross-sectional view showing an example of the force acting on the terminal portion 88 of the spark plug 80 from the clip springs 40A and 40B of the present embodiment. In this example, the force acting on the terminal portion 88 of FIG. 20 is shown.

As described above, the clip springs 40A and 40B are fitted into the notch holes 34A and 34B of the cylindrical portion 33 from opposite directions in the radial direction of the tubular portion 33, respectively. The clip spring 40A exerts a force FA on the terminal portion 88, and the clip spring 40B exerts a force FB on the terminal portion 88. The action point of the force FA that the clip spring 40A pushes the terminal portion 88 and the action point of the force FB that the clip spring 40B pushes the terminal portion 88 are different from each other in the circumferential direction of the terminal portion 88. That is, the clip springs 40A and 40B push the terminal portions 88 in different radial directions.

Therefore, the component FA of the force that pushes the terminal portion 88 in the Y direction (second direction) that is perpendicular to the X direction (first direction) that is the radial direction in which the clip spring 40B pushes the terminal portion 88. -Sin φ1 is generated. Therefore, when the ignition coil 10 and the spark plug 80 vibrate not only in the X direction but also in the Y direction, the component FA · sinφ1 of the force that the clip spring 40A pushes the terminal portion 88 causes the terminal portion 88 to vibrate. The vibration of the ignition coil 10 due to the vibration can be suppressed. As a result, the vibration of the ignition coil 10 can be suppressed regardless of the direction in which the ignition coil 10 and the spark plug 80 vibrate.

FIG. 23 is a cross-sectional view showing another example of the force acting on the terminal portion 88 of the spark plug 80 from the clip springs 40A and 40B of the present embodiment. In this example, the force acting on the terminal portion 88 of FIG. 21 is shown.

Similar to FIG. 22, the action point of the force FA that the clip spring 40A pushes the terminal portion 88 and the action point of the force FB that the clip spring 40B pushes the terminal portion 88 are different from each other in the circumferential direction of the terminal portion 88. ing. In particular, in FIG. 23, the X direction (first direction), which is the radial direction in which the clip spring 40B pushes the terminal portion 88, is in the Y direction (second direction), which is the radial direction in which the clip spring 40A pushes the terminal portion 88. It is vertical.

Therefore, the force FB that the clip spring 40B pushes the terminal portion 88 and the force FA that the clip spring 40A pushes the terminal portion 88 are vertical and have the same magnitude. Therefore, even when the ignition coil 10 and the spark plug 80 vibrate in the Y direction, the vibration of the ignition coil 10 can be suppressed in the same manner as when the ignition coil 10 and the spark plug 80 vibrate in the X direction. As a result, the vibration of the ignition coil 10 can be suppressed evenly regardless of the direction in which the ignition coil 10 and the spark plug 80 vibrate.

The present embodiment described in detail above has the following advantages.

The clip springs 40A and 40B are fitted into the notch holes 34A and 34B of the cylindrical portion 33 from opposite directions in the radial direction of the tubular portion 33, respectively. The points of action of the clip springs 40A and 40B engaged with the valleys (recesses) of the male screw 88a of the terminal portion 88 to push the terminal portion 88 are different from each other in the circumferential direction of the terminal portion 88. Therefore, there are clip springs 40A and 40B that push the terminal portion 88 in different radial directions, and the radial direction (Y direction) perpendicular to the radial direction (X direction) in which the clip spring 40B pushes the terminal portion 88. ), The component FA · sinφ1 of the force FA that pushes the terminal portion 88 is generated. Therefore, when the ignition coil 10 and the spark plug 80 vibrate not only in the X direction but also in the Y direction, the ignition coil 10 due to the vibration of the terminal portion 88 due to the force of the clip spring 40A pushing the terminal portion 88. Vibration can be suppressed. As a result, the vibration of the ignition coil 10 can be suppressed regardless of the direction in which the ignition coil 10 and the spark plug 80 vibrate. Further, it is not necessary to adjust the direction of the ignition coil 10 with respect to the direction in which the ignition coil 10 and the spark plug 80 vibrate.

When the lengths of the notch holes 34A and 34B in the circumferential direction of the tubular portion 33 are too short, the clip springs 40A and 40B have the notch holes 34A and 34B of the tubular portion 33 from opposite directions in the radial direction of the tubular portion 33. Even if they are fitted to 34B, the clip springs 40A and 40B may push the terminal portion 88 of the spark plug 80 in substantially the same radial direction. In this respect, the lengths of the cutout holes 34A and 34B in the circumferential direction of the tubular portion 33 are set longer than the half circumference of the tubular portion 33. According to such a configuration, the clip springs 40A and 40B surely push the terminal portions 88 in different radial directions, and the vibration of the ignition coil 10 is surely irrespective of the direction in which the ignition coil 10 and the spark plug 80 vibrate. It can be suppressed.

When the lengths of the cutout holes 34A and 34B in the circumferential direction of the tubular portion 33 are longer than the half circumference of the tubular portion 33, the length of the clip springs 40A and 40B that fit into the outer peripheral portion of the tubular portion 33 is short. Become. In this case, before inserting the terminal portion 88 of the spark plug 80 into the tubular portion 33, the clip springs 40A and 40B may rotate along the outer peripheral surface of the tubular portion 33. In this regard, the clip springs 40A and 40B are provided with a detent 43 for stopping the clip springs 40A and 40B from rotating along the outer peripheral surface of the tubular portion 33. According to such a configuration, even when the lengths of the cutout holes 34A and 34B in the circumferential direction of the tubular portion 33 are longer than the half circumference of the tubular portion 33, the terminal portion 88 of the spark plug 80 is connected to the tubular portion 33. It is possible to prevent the clip springs 40A and 40B from rotating along the outer peripheral surface of the tubular portion 33 before the insertion.

The notch hole 34A and the notch hole 34B are formed at the same position in the circumferential direction of the tubular portion 33, that is, in parallel. Therefore, when forming the cutout holes 34A and 34B in the cylindrical portion 33, the machining can be performed in the same direction, and it is not necessary to adjust the machining direction (angle). As a result, the labor and cost of processing can be reduced. Further, the vibration of the ignition coil 10 can be suppressed only by reversing the directions in which the clip springs 40A and 40B are fitted into the notch holes 34A and 34B of the tubular portion 33, respectively.

In the above embodiment, the notch holes 34A and 34B may be formed at the same position in the circumferential direction of the tubular portion 33, and the shapes (lengths) may be different.

(Second Embodiment)
Hereinafter, the second embodiment will be described with reference to the drawings. In the present embodiment, the notch holes 34A and 34B are formed at different positions in the circumferential direction of the tubular portion 33 of the high voltage terminal 30.

FIG. 24 is a side view showing an example of the high voltage terminal 30 of the present embodiment. FIG. 25 is a cross-sectional view taken along the line XXV-XXV of FIG. 24. In this example, the length of the notch hole 34B (34A) in the circumferential direction of the tubular portion 33 is set shorter than the half circumference of the tubular portion 33, as in the prior art shown in FIGS. 3 to 5.

The notch hole 34A is formed at the same position as the notch hole 34A in FIGS. 13 and 14 and has the same shape. On the other hand, the notch hole 34B is formed at a position 90 ° away from the notch hole 34A in the circumferential direction of the tubular portion 33. That is, the notch holes 34A and 34B are formed at different positions in the circumferential direction of the tubular portion 33, respectively.

As shown in FIGS. 26 to 28, the clip springs 40A and 40B are fitted into the cutout holes 34A and 34B of the tubular portion 33 of the high voltage terminal 30 from the directions forming 90 ° (predetermined angle) with each other. .. 27 is a cross-sectional view taken along the line XXVII-XXVII of FIG. 26, and FIG. 28 is a cross-sectional view taken along the line XXVIII-XXVIII of FIG. 26. Hereinafter, the differences from the first embodiment will be mainly described.

As shown in FIG. 27, the fitting portion 42 of the clip spring 40A is in contact with each of the two wall portions 35 corresponding to the extension of the notch hole 34A.

As shown in FIG. 28, the clip spring 40B is fitted into the notch hole 34B of the tubular portion 33 from a direction forming 90 ° (predetermined angle) with respect to the direction in which the clip spring 40A is fitted. Other points are the same as the clip spring 40A.

FIG. 29 is a partial cross-sectional view showing a connection structure between the ignition coil 10 and the spark plug 80 of the present embodiment. FIG. 30 is a cross-sectional view taken along the line XXX-XXX of FIG. 29.

When the terminal portion 88 of the spark plug 80 is inserted into the tubular portion 33, the clip springs 40A and 40B are pushed open by the terminal portion 88. At this time, as shown in FIG. 30, the clip spring 40B rotates in the rotation direction (clockwise in FIG. 30) continuing from the fitting portion 42 to the holding portion 41. However, the rotation of the clip spring 40B is restricted by the contact of the fitting portion 42 with the outer end portion 35a of the wall portion 35 on the connecting portion side between the fitting portion 42 and the holding portion 41. On the other hand, the clip spring 40A rotates in the rotation direction (clockwise in FIG. 30) continuing from the fitting portion 42 to the holding portion 41. However, the rotation of the clip spring 40A is restricted by the contact of the fitting portion 42 with the outer end portion 35a of the wall portion 35 on the connecting portion side between the fitting portion 42 and the holding portion 41. In this state, the clip spring 40A and the clip spring 40B form an angle of 90 ° in the circumferential direction of the tubular portion 33. That is, the clip spring 40B is arranged at a position where the clip spring 40A is rotated 90 ° clockwise in the circumferential direction of the tubular portion 33.

FIG. 31 is a cross-sectional view showing an example of the force acting on the terminal portion 88 of the spark plug 80 from the clip springs 40A and 40B of the present embodiment.

The clip springs 40A and 40B are fitted into the cutout holes 34A and 34B of the tubular portion 33 from the directions forming a predetermined angle φ3 with each other. The predetermined angle φ3 is set to be greater than 0 ° and 90 ° or less (0 ° <φ3 ≦ 90 °). The clip spring 40A exerts a force FA on the terminal portion 88, and the clip spring 40B exerts a force FB on the terminal portion 88. The action point of the force FA that the clip spring 40A pushes the terminal portion 88 and the action point of the force FB that the clip spring 40B pushes the terminal portion 88 are different from each other in the circumferential direction of the terminal portion 88. That is, the clip springs 40A and 40B push the terminal portions 88 in different radial directions (diameter directions forming a predetermined angle φ3 with each other).

Therefore, the component FA of the force that pushes the terminal portion 88 in the Y direction (second direction) that is perpendicular to the X direction (first direction) that is the radial direction in which the clip spring 40B pushes the terminal portion 88. -Sin φ3 is generated. Therefore, when the ignition coil 10 and the spark plug 80 vibrate not only in the X direction but also in the Y direction, the clip spring 40A pushes the terminal portion 88 due to the component FA · sinφ3 of the force of the terminal portion 88. The vibration of the ignition coil 10 due to the vibration can be suppressed. As a result, the vibration of the ignition coil 10 can be suppressed regardless of the direction in which the ignition coil 10 and the spark plug 80 vibrate.

FIG. 32 is a cross-sectional view showing another example of the force acting on the terminal portion 88 of the spark plug 80 from the clip springs 40A and 40B of the present embodiment. In this example, the force acting on the terminal portion 88 of FIGS. 29 and 30 is shown.

Similar to FIG. 31, the action point of the force FA that the clip spring 40A pushes the terminal portion 88 and the action point of the force FB that the clip spring 40B pushes the terminal portion 88 are different from each other in the circumferential direction of the terminal portion 88. ing. In particular, in FIG. 32, the X direction (first direction), which is the radial direction in which the clip spring 40B pushes the terminal portion 88, is in the Y direction (second direction), which is the radial direction in which the clip spring 40A pushes the terminal portion 88. It is vertical.

Therefore, the force FB that the clip spring 40B pushes the terminal portion 88 and the force FA that the clip spring 40A pushes the terminal portion 88 are vertical and have the same magnitude. Therefore, even when the ignition coil 10 and the spark plug 80 vibrate in the Y direction, the vibration of the ignition coil 10 can be suppressed in the same manner as when the ignition coil 10 and the spark plug 80 vibrate in the X direction. As a result, the vibration of the ignition coil 10 can be suppressed evenly regardless of the direction in which the ignition coil 10 and the spark plug 80 vibrate.

The present embodiment described in detail above has the following advantages. Here, only the advantages different from the first embodiment will be described.

A plurality of notch holes 34A and 34B arranged in the axial direction of the tubular portion 33 are formed at different positions in the circumferential direction of the tubular portion 33, respectively. The plurality of clip springs 40A and 40B are fitted into the plurality of notch holes 34A and 34B, respectively. Therefore, the clip springs 40A and 40B push the terminal portion 88 inserted inside the tubular portion 33 in different radial directions. Therefore, the component FA · sinφ3 of the force that pushes the terminal portion 88 in the radial direction (Y direction) perpendicular to the radial direction (X direction) in which the clip spring 40B pushes the terminal portion 88 is generated. As a result, the vibration of the ignition coil 10 can be suppressed regardless of the direction in which the ignition coil 10 and the spark plug 80 vibrate.

When the notch holes 34A and 34B are formed at positions separated from each other by a predetermined angle φ3 in the circumferential direction of the tubular portion 33, the clip springs 40A and 40B are respectively formed of the spark plug 80 from the radial direction forming the predetermined angle φ3. The terminal portion 88 will be pressed. At this point, the plurality of notch holes 34A and 34B are formed at positions separated from each other by 90 ° in the circumferential direction of the tubular portion 33, respectively. According to such a configuration, the clip springs 40A and 40B push the terminal portions 88 from the radial directions forming 90 ° with each other. Therefore, a force that the clip spring 40B pushes the terminal portion 88 in the radial direction (X direction) and a force that the clip spring 40A pushes the terminal portion 88 in the radial direction (Y direction) perpendicular to the X direction act. Therefore, the vibration of the ignition coil 10 can be effectively suppressed regardless of the direction in which the ignition coil 10 and the spark plug 80 vibrate.

In the above embodiment, the shapes (lengths) of the cutout holes 34A and 34B can be made different.

Further, each of the above embodiments can be modified and implemented as follows. The same parts as those in each of the above embodiments are designated by the same reference numerals, and the description thereof will be omitted.

-The shape of the high voltage terminal 30 can be changed to adopt the high voltage terminal 130 shown in FIG. 33. The basic function of the high voltage terminal 130 is the same as that of the high voltage terminal 30. A groove 39 in which the holding portions 41 of the clip springs 40A and 40B are fitted is formed on the outer peripheral portion of the tubular portion 133 of the high voltage terminal 130. Further, a stepped portion 188a (diameter-reduced portion) is formed on the outer peripheral portion of the terminal portion 188 of the spark plug 80. Then, the fitting portions 42 of the clip springs 40A and 40B are engaged with the valley portion or the tapered portion (recessed portion) of the step portion 188a via the notch holes 34A and 34B of the tubular portion 133, respectively. Here, the clip springs 40A and 40B are fitted into the notch holes 34A and 34B of the cylindrical portion 133 from opposite directions in the radial direction of the tubular portion 33, respectively. Even with such a configuration, the action and effect according to the first embodiment can be obtained.

The cross-sectional shape of the clip springs 40A and 40B is not limited to a circle, but may be a triangle, a hexagon, or the like.

-Three or more notch holes can be formed in the cylindrical portions 33 and 133, and three or more clip springs can be fitted into the notch holes, respectively.

10 ... Ignition coil, 21 ... Secondary coil, 30 ... High voltage terminal, 33 ... Cylindrical part, 34A ... Notch hole, 34B ... Notch hole, 40A ... Clip spring, 40B ... Clip spring, 80 ... Spark plug, 88 ... Terminal part, 130 ... High voltage terminal, 133 ... Cylindrical part, 188 ... Terminal part, 188a ... Step part.

Claims (7)

High-voltage terminals (30, 130) having a cylindrical portion (33, 133) formed in a cylindrical shape and connected to a secondary coil (21).
An ignition coil (10) including a plurality of clip springs (40A, 40B) fitted to the outer peripheral portion of the tubular portion.
A plurality of notches (34A, 34B) arranged in the axial direction are formed at the same position in the circumferential direction on the outer peripheral portion of the tubular portion.
The plurality of clip springs are ignition coils including clip springs fitted in the notch holes of the tubular portion from opposite directions in the radial direction of the tubular portion. The ignition coil according to claim 1, wherein the length of the notch hole in the circumferential direction of the tubular portion is set longer than the half circumference of the tubular portion. The ignition coil according to claim 2, wherein the clip spring is provided with a detent (43) for stopping the clip spring from rotating along the outer peripheral surface of the tubular portion. A connection structure for connecting the ignition coil according to any one of claims 1 to 3 and a spark plug (80).
The spark plug includes a terminal portion (88, 188) having a concave portion (88a, 188a) formed on the outer peripheral portion and inserted into the tubular portion.
The plurality of clip springs are respectively engaged with the recesses of the terminal portion via the plurality of notch holes.
The points of action of the plurality of clip springs engaged with the recesses to push the terminal portions are the ignition coil and the spark plug, including the points of action of pushing the terminal portions at different positions in the circumferential direction of the terminal portions. Connection structure. High-voltage terminals (30, 130) having a cylindrical portion (33, 133) formed in a cylindrical shape and connected to a secondary coil (21).
A connection structure for connecting a plurality of clip springs (40A, 40B) fitted to the outer peripheral portion of the tubular portion, an ignition coil (10) including the ignition coil (10), and a spark plug (80).
A plurality of notches (34A, 34B) arranged in the axial direction are formed on the outer peripheral portion of the tubular portion.
The plurality of notch holes include notches formed at different positions in the circumferential direction of the tubular portion.
The plurality of clip springs are fitted into the plurality of notch holes, respectively.
The spark plug includes a terminal portion (88, 188) having a concave portion (88a, 188a) formed on the outer peripheral portion and inserted into the tubular portion.
The plurality of clip springs are respectively engaged with the recesses of the terminal portion via the plurality of notch holes.
The points of action of the plurality of clip springs engaged with the recesses to push the terminal portions are the ignition coil and the spark plug, including the points of action of pushing the terminal portions at different positions in the circumferential direction of the terminal portions. Connection structure. The connection structure between an ignition coil and a spark plug according to claim 5 , wherein the plurality of notch holes include notches formed at positions 90 ° apart from each other in the circumferential direction of the tubular portion. It is a connection structure that connects the ignition coil (10) and the spark plug (80).
The ignition coil is
High-voltage terminals (30, 130) having a cylindrical portion (33, 133) formed in a cylindrical shape and connected to a secondary coil (21).
A plurality of clip springs (40A, 40B) fitted to the outer peripheral portion of the tubular portion are provided.
The spark plug includes a terminal portion (88, 188) having a concave portion (88a, 188a) formed on the outer peripheral portion and inserted into the tubular portion.
A plurality of notches (34A, 34B) arranged in the axial direction are formed on the outer peripheral portion of the tubular portion.
The plurality of clip springs are respectively engaged with the recesses of the terminal portion via the plurality of notch holes.
The points of action of the plurality of clip springs engaged with the recesses to push the terminal portions are the ignition coil and the spark plug, including the points of action of pushing the terminal portions at different positions in the circumferential direction of the terminal portions. Connection structure.

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