JPH1032075A - High pressure spark plug cap - Google Patents

Abstract

[PROBLEMS] To provide a high-pressure spark plug cap improved so that an operation of inserting a high-pressure spark plug into an internal combustion engine can be easily and reliably connected. SOLUTION: The high pressure spark plug cap 20 of the present invention is provided.
A spring contact 36 which can be compressed and deformed along the axis A of the high-pressure cord 5;
And a female plug terminal 34 formed of a female plug terminal 34 formed on the inner peripheral surface near the upper end of the engine hole portion 1. Since the elastic fixing member 24 is held on the outer peripheral surface of the closer cord cap portion 29 and the receiving seat 32 that allows the locking claw portion 28 of the elastic fixing member 24 to be able to engage with the engaging concave portion 39 is provided so as to protrude. The operation of inserting the high-pressure spark plug cap 20 is performed simply by lightly pushing in the work other than the work of fitting the lower end face of the cord cap section 29 and the groove formed in the upper end face of the elastic cap section 38. The completion of the fitting operation is easily confirmed by the engagement sound of the locking claw portion 28 with the engagement concave portion 39.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cap for a high-pressure spark plug improved so that a high-pressure spark plug can be easily and reliably connected to an internal combustion engine.

[0002]

2. Description of the Related Art A conventional high-pressure spark plug cap for an internal combustion engine is generally composed of a combination as shown in a longitudinal sectional view of FIG.

That is, the conventional high pressure spark plug cap 10
A cord cap portion 14 which houses the high-voltage cord 5 connected to the power supply and is entirely formed of an insulating synthetic resin into a substantially cylindrical shape, and is fitted to an upper end of the cord cap portion 14; The upper surface 2 of the engine head is pressed by a seal lip portion 12 protruding from the outer peripheral edge of the flange, and the cylindrical straight body portion 13 is provided inside the upper end of the vertical hole-shaped engine hole portion 1 penetrated through the engine head. A rain cover part 11 for sealing around the upper end of the engine hole part 1 by fitting
A cord fixing portion 15 that penetrates through the side surface of the rain cover portion 11 and that closely contacts and grips the vicinity of the terminal portion of the high-pressure cord 5 disposed at the lower end of the cord cap portion 14 from the outer surface by compression deformation. The female plug terminal 17 is formed by bridging the outer peripheral surface of the peripheral wall with a half-ring portion 16 so that the vertical mating edge (not shown) of the peripheral wall formed into a cylindrical shape and curved into a cylindrical shape does not widen. , Respectively.

[0004] The conventional high-pressure ignition plug cap 10 constructed as described above is fitted from above to a plug head (not shown) of the high-pressure ignition plug 4 screwed to the bottom 3 of the engine hole 1. The lower end surface of the cord cap portion 14 is fitted into a groove formed in the upper end surface of the elastic cap portion 18 made of an insulating synthetic resin, so that the high-pressure ignition plug portion 4 and the female plug terminal 17 are fitted. Electrical connection was made.

[0005]

However, the above-described conventional high-pressure spark plug cap 10 is inserted into the engine hole portion 1 and the high-pressure spark plug portion 4,
The fixed state greatly depends on the following three degrees of fitting. That is, the cylindrical straight body portion 13 of the rain cover portion 11
And the upper end of the engine hole 1, the lower end of the cord cap 14 and the elastic cap 18.
And the degree of fitting between the plug head of the high-pressure ignition plug part 4 and the female plug terminal 17.

The degree of fitting of these three places is determined in order to maintain good sealing and insulating properties at both ends of the engine hole part 1 and also to maintain good electrical connection of the high-pressure spark plug part 4.
It is necessary to set a considerable interference fit, and as a result, it takes a lot of labor and time to insert the high-pressure spark plug 4 into the internal combustion engine, and it is difficult to improve the assembling workability. there were.

An object of the present invention is to provide an improved high-pressure spark plug cap that solves the above-mentioned problems of the prior art and that enables a high-pressure spark plug to be easily and securely connected to an internal combustion engine. It is intended for.

[0008]

SUMMARY OF THE INVENTION The object of the present invention is as follows.
A code cap portion formed by molding an insulating synthetic resin into a substantially cylindrical shape, and the upper surface of the code cap portion is fitted and pressed against the upper surface of the engine head by a seal lip portion protruding from an outer peripheral edge of the flange. A rain cover portion through which the high-pressure cord can be inserted, and a cord fixing portion that close-contacts and grips the vicinity of the end of the high-pressure cord provided at the lower end of the code cap portion from the outer surface by compressive deformation. A female plug terminal formed of a spring contact formed integrally with the high-pressure cord and compressible along the axis of the high-voltage cord;
A high-pressure ignition plug cap, wherein the engine hole portion penetrated from the upper surface of the engine head has an engagement recess formed in an inner peripheral surface near an upper end thereof, while the cord has A cap portion supports an elastic fixing member fitted from an upper end of the cord cap portion on an outer peripheral surface closer to the female plug terminal than the engagement recess, and is disposed corresponding to the engagement recess. This is achieved by a cap for a high-pressure ignition plug, characterized in that a receiving seat is formed so as to be able to engage the locking claw portion of the elastic fixing member with the engaging recess.

Further, it is another object of the present invention that the rain cover portion has a recess formed therein so as to be able to receive swinging movement of a tip end of an elastic arm portion of the elastic fixing member. Achieved by the featured high pressure spark plug cap.

Further, the object of the present invention is that the cord cap portion projects a locking ridge on an outer peripheral surface above the receiving seat, and the elastic fixing member has an inner peripheral portion of a cylindrical body portion. The present invention is attained by a cap for a high-pressure spark plug, characterized in that an engaging groove engageable with the locking ridge is formed on a surface thereof.

Further, the object of the present invention is to provide a vertically long lock in which the cord cap portion can house the lock member so that a part of the lock member can be engaged with the engagement recess on the outer peripheral surface thereof. This is achieved by a cap for a high-pressure spark plug, characterized in that a housing is protruded.

The high-pressure spark plug cap of the present invention is fitted to a cord cap portion formed of an insulating synthetic resin into a substantially cylindrical shape, and to the upper end of the cord cap portion, and protrudes from the outer peripheral edge of the flange. A seal cover lip presses the upper surface of the engine head, while penetrating the side surface to insert a high-pressure cord, and a terminal portion of the high-pressure cord disposed at a lower end of the code cap. A female plug terminal formed of a spring contact formed integrally with a cord fixing portion that is tightly held and gripped by compression deformation from an outer surface and is compressively deformable along the axis of the high-pressure cord;
A high-pressure ignition plug cap, wherein the engine hole portion penetrated from the upper surface of the engine head has an engagement recess formed in an inner peripheral surface near an upper end thereof, while the cord has A cap portion holds an elastic fixing member fitted from an upper end of the cord cap portion on an outer peripheral surface closer to the female plug terminal than the engagement concave portion, and is disposed corresponding to the engagement concave portion. A receiving seat that allows the engaging claw portion of the elastic fixing member to be engaged with the engaging recess is projected, so that the operation of inserting the high-pressure ignition plug cap into the engine hole is performed by the cord cap The work of fitting the lower end face of the part and the groove formed in the upper end face of the elastic cap part only requires the same labor as in the past, and other fitting work is completed by simply pushing lightly. The engagement of the locking claw portion Easily confirm completion of the fitted working by engagement sounds for parts.

Further, in the cap for a high-pressure ignition plug of the present invention, the rain cover portion has a recess formed therein so as to be able to receive the swinging movement of the distal end portion of the elastic arm portion of the elastic fixing member. Therefore, the length of the elastic arm portion can be set to be long, and as a result, the operation of attaching and detaching the elastic fixing member to and from the receiving seat becomes easy by using the long elastic arm portion.

Further, in the cap for a high-pressure ignition plug according to the present invention, the cord cap portion projects a locking ridge on an outer peripheral surface above the receiving seat, and the elastic fixing member has a cylindrical body portion. Since the engagement groove engageable with the locking ridge is formed in the inner peripheral surface of the elastic member, the positioning of the elastic fixing member with respect to the engagement concave portion is accurately performed, and the function of preventing rotation is provided. .

Further, in the cap for a high-pressure ignition plug according to the present invention, the cord cap portion may have a vertically long portion in which the lock member can be housed so that a part of the lock member can be engaged with the engagement recess on the outer peripheral surface thereof. Since the lock storage portion is formed in a protruding manner, the structure of the elastic fixing member is further simplified, and the load of the fitting work is reduced. Further, if the lock member is made of an independent metal spring material, a more metallic engagement sound can be obtained, so that it is easier to confirm the completion of the fitting operation.

DETAILED DESCRIPTION OF THE INVENTION An embodiment of the high-pressure ignition plug cap of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view showing a high-pressure spark plug cap 20 of the present invention applied to the spark plug 4 of an internal combustion engine. FIG. 2 is an exploded view of a main part of the high-pressure spark plug cap 20 of FIG. It is the perspective view shown. FIG. 3 is a longitudinal sectional view showing a modified example of the high-pressure spark plug cap 20 of the present invention applied to the spark plug 4 of the internal combustion engine. FIG. 4 shows a main part of the high-pressure spark plug cap 20 of FIG. It is the perspective view shown exploded.

The high-pressure spark plug cap 20 of the present invention shown in FIGS. 1 and 2 has a cord cap portion 29 made of an insulating synthetic resin formed into a substantially cylindrical shape, and is fitted to the upper end of the cord cap portion 29. While the upper surface 2 of the engine head is pressed by the seal lip portion 22 protruding from the outer peripheral edge of the flange.
A rain cover portion 21 through which the high-pressure cord 5 can be inserted and a terminal portion of the high-pressure cord 5 disposed at a lower end of the code cap portion 29 are closely adhered and gripped from the outer surface by compression deformation. And a female plug terminal 34 formed of a spring contact 35 that is formed integrally with the cord fixing portion 35 and that can be compressed and deformed along the axis A of the high-pressure cord 5.

Further, the high-pressure spark plug cap 20
Are provided on the inner peripheral surface near the upper end of the engine hole portion 1 penetrated from the upper surface 2 of the engine head.
While the concave portion 39 is provided, the code cap portion 29 is provided on the outer peripheral surface closer to the female plug terminal 34 than the engagement concave portion 39,
The retaining claw 28 of the elastic fixing member 24, which holds the elastic fixing member 24 fitted from the upper end of the cord cap portion 29 and is disposed corresponding to the engaging concave portion 40, is engaged with the engaging concave portion. A receiving seat 32 which can be engaged with 39 is protrudedly provided.

As shown in FIG. 2, the elastic fixing member 24 includes a cylindrical frame portion 25; a plurality of vertically long support plate portions 26 projecting from the outer peripheral surface of the cylindrical frame portion 25; Plate 26
A locking claw portion, which is raised from the lower end portion of the outer peripheral surface while being slightly inclined outward from the lower end portion of the cylindrical body portion 25 defined by
28; an elastic arm 27 raised substantially vertically from an upper end of the locking claw 28; a plurality of vertically long engaging grooves 33 engraved on the inner peripheral surface of the cylindrical body 25; Each is integrally molded.

On the other hand, the rain cover portion 21 is provided with a concave portion 23 in the inside thereof for receiving the distal end portion of the elastic arm portion 27 so that the distal end portion can swing with the fitting operation. The seal lip 22 is provided so as to protrude from the outer peripheral edge of the flange so as to surround the lower end of the recess 23. The seal lip 22 presses the inner peripheral surface of the seal lip 22 rather than simply presses the completely flat upper surface 2 of the engine head with its edge to maintain and improve the sealing performance. It is valid.

Further, the cord cap portion 29 is provided with the seat
A plurality of vertically elongated locking ridges 31 are provided on the outer peripheral surface above 32 so as to correspond to the plurality of vertically long engaging grooves 33 formed on the inner peripheral surface of the cylindrical body 25. It consists of

The high pressure ignition plug cap 20 of the present invention shown in FIGS. 1 and 2 having the above-described structure, first has the elastic fixing member 24 attached to the upper end of the cord cap portion 29.
The lower end portions of the cylindrical body portion 25 and the support plate portion 26 are received while the engagement groove 33 is engaged with the locking ridge 31 while the cylindrical body portion 25 is fitted. The relative positional relationship between the cord cap portion 29 and the elastic fixing member 24 is determined by contacting the upper surface of the seat 32.

Next, while the high-pressure cord 5 penetrating from the side face is fitted into the cutout 30 provided at the upper end of the cord cap 29, the rain cover 21 is placed above the cord cap 29. By fitting to the end,
The rain cover part 21 is inserted through the cord cap part 29.
And the elastic fixing member 24 are integrated. Further, when the female plug terminal 34 fixed near the terminal portion of the high-voltage cord 5 is disposed at a predetermined position inside the lower end of the code cap portion 29, the cap 20 for a high-pressure ignition plug of the present invention is provided. Preparation for fitting operation is completed.

Next, when the high-pressure spark plug cap 20 is inserted from the upper end of the engine hole portion 1 toward the plug head 37 of the high-pressure spark plug portion 4 screwed to the bottom portion 3, The lower end surface of the cord cap portion 29 is fitted into a groove formed in the upper end surface of the elastic cap portion 38, so that the plug head 37 and the spring contact
36 makes elastic contact and completes the electrical connection.

In parallel with the contact between the plug head 37 and the spring contact 36, the locking claw 28 of the elastic fixing member 24 fitted to the upper end of the cord cap 29 is mounted on the engine. The upper end portion of the hole portion 1 is slid in contact with the inner peripheral surface of the upper end portion, and is once bent inward. Thereafter, it is engaged with the engaging concave portion 39 and the bent state is also returned to the origin. The elastic arm portion 27 coupled to the locking claw portion 28 swings in the radial direction of the engine hole portion 1 in accordance with the bending change of the locking claw portion 28. Since it is received, its swinging displacement is not hindered, and a smooth spring action of the locking claw 28 is promoted. The elastic arm 27 can be more easily attached to and detached from the cord cap 29 by gripping the distal end thereof. However, the internal space of the rain cover 21 is reduced due to the design of the rain cover 21. In this case, even if the length of the elastic arm 27 is shortened or omitted altogether, the basic spring operation of the locking claw 28 is not fatally affected.

In addition, the inner peripheral surface of the seal lip portion 22 presses the rain cover portion 21 against the upper surface 2 of the engine head, thereby maintaining and improving the sealing performance around the periphery.
Therefore, the operation of inserting the high-pressure spark plug cap 20 into the engine hole 1 is performed by fitting the lower end face of the cord cap section 29 and the groove formed in the upper end face of the elastic cap section 38. Only the same labor as in the prior art is required, and other fitting operations can be completed by simply pushing lightly, and the fitting sound can be easily completed by the engagement sound of the locking claw portion 28 with the engaging recess 39. Can be confirmed. The engagement recess 39 may be formed in a continuous groove shape along the circumferential direction of the inner peripheral surface of the engine hole portion 1.

Another cap 20 for a high-pressure spark plug according to the present invention shown in FIGS. 3 and 4 is a lock formed by bending a substantially V-shape on the outer peripheral surface of the cord cap portion 29 instead of the elastic fixing member 24. A vertically long lock housing portion 40 for housing the lock member 43 is provided so as to protrude so that the bent projection of the member 43 can be engaged with the engagement recess 39. The lock accommodating portion 40 is formed by inserting the bent protrusion portion of the lock member 43 inserted through an insertion hole 42 provided on an upper end surface thereof through a vertically elongated slit portion 41 penetrating a surface opposed to the engine hole portion 1. Engage with the mating recess 39. Therefore, the structure of the elastic fixing member is further simplified, and the load of the fitting operation is reduced. If the lock member 43 is made of an independent metal spring material, a more metallic engagement sound can be obtained, so that it is easier to confirm the completion of the fitting operation.

[0028]

The high pressure spark plug cap 20 of the present invention having the above-described structure has the following novel effects. That is, the high-pressure ignition plug cap 20 of the present invention is fitted on the upper end of the cord cap portion 29 formed of an insulating synthetic resin into a substantially cylindrical shape, and on the outer peripheral edge of the flange. The rain cover portion 21 through which the high pressure cord 5 can be inserted while penetrating the upper surface 2 of the engine head with the projecting seal lip portion 22;
The end portion of the high-voltage cord 5 disposed at the lower end of 29 is formed integrally with the cord fixing portion 35 that closely adheres and grips from the outer surface by compressive deformation, and is formed integrally with the axis A of the high-pressure cord 5. And the female plug terminal 34 comprising the spring contact 36 which can be compressed and deformed along the upper surface of the engine head. While the engagement recess 39 is recessed on the inner peripheral surface of the cord cap portion 29, the upper end of the code cap portion 29 is located on the outer peripheral surface closer to the female plug terminal 34 than the engagement recess 39. The engaging claw 28 of the elastic fixing member 24 provided corresponding to the engaging concave portion 39 can be engaged with the engaging concave portion 39. Since the receiving seat 32 is protruded, the engine hole 1 The insertion operation of the high-pressure spark plug cap 20, the code cap portion 29 against
The work of fitting the lower end face of the lower end face and the groove formed in the upper end face of the elastic cap part 38 requires only the same labor as in the past, and other fitting work is completed by simply pushing lightly,
The completion of the fitting operation can be easily confirmed by the engagement sound of the locking claw portion 28 with the engagement concave portion 39.

Furthermore, the cap for a high-pressure spark plug of the present invention
20, the rain cover portion 21 is formed by recessing the concave portion 23 capable of receiving the swinging movement of the distal end portion of the elastic arm portion 27 of the elastic fixing member 24 therein. The length of the portion 27 can be set to be long. As a result, the use of the long elastic arm portion 27 makes it easy to attach and detach the elastic fixing member 24 to and from the receiving seat 32.

Furthermore, the cap for a high-pressure spark plug of the present invention
20, the cord cap portion 29 projects the locking ridge 31 on the outer peripheral surface above the receiving seat 33, while the elastic fixing member 24 is attached to the inner peripheral surface of the cylindrical body portion 25. Since the engaging groove 33 engageable with the locking ridge 31 is formed in a concave shape, the positioning of the elastic fixing member 24 with respect to the engaging concave portion 39 is accurate, and a function of preventing rotation is provided. It became possible.

Further, a cap for a high-pressure spark plug according to the present invention.
20 is a vertically long lock storage portion in which the code cap portion 29 can store the lock member 43 so that a part of the lock member 44 can be engaged with the engagement concave portion 39 on the outer peripheral surface thereof.
Since the protrusions 40 are provided, the structure of the elastic fixing member is further simplified, and the load of the fitting operation can be reduced. Further, if the lock member 43 is made of an independent metal spring material, a more metallic engagement sound can be obtained, so that the completion of the fitting operation can be more easily confirmed.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a cap for a high-pressure spark plug of the present invention applied to a spark plug of an internal combustion engine.

FIG. 2 is an exploded perspective view showing a main part of the high-pressure ignition plug cap of FIG. 1;

FIG. 3 is a longitudinal sectional view showing a modified example of the high-pressure spark plug cap of the present invention applied to the spark plug of the internal combustion engine.

FIG. 4 is an exploded perspective view showing an essential part of the high-pressure ignition plug cap of FIG. 2;

FIG. 5 is a longitudinal sectional view showing a conventional high-pressure ignition plug cap applied to an ignition plug of an internal combustion engine.

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 Engine hall part 2 Top of engine head 3 Bottom part of engine hole 4 Spark plug part 5 High pressure cord 10 Conventional high pressure ignition plug cap 11 Rain cover part 12 Seal lip part 13 Cylindrical straight body part 14 Code cap part 15 Cord fixing Part 16 Half ring part 17 Female plug terminal 18 Elastic cap part 20 Cap for high-pressure ignition plug of the present invention 21 Rain cover part 22 Seal lip part 23 Depression 24 Elastic fixing member 25 Cylindrical skeleton part 26 Support plate part 27 Elastic arm part 28 Locking claw portion 29 Code cap portion 30 Notch portion 31 Locking ridge 32 Receiving seat 33 Engagement groove 34 Female plug terminal 35 Cord fixing portion 36 Spring contact 37 Plug head 38 Elastic cap portion 39 Engagement concave portion 40 Lock storage part 41 Slit part 42 Insertion hole 43 Lock member A Shaft core

Claims (4)

[Claims] 1. An upper surface of an engine head having a code cap portion formed by molding an insulating synthetic resin into a substantially cylindrical shape, and a seal lip portion fitted to an upper end of the code cap portion and protruding from an outer peripheral edge of the flange. While pressing, a rain cover portion that can insert a high-pressure cord through the side surface thereof, and close to the terminal portion of the high-pressure cord disposed at the lower end of the code cap portion by compression deformation from the outer surface, A high-pressure spark plug cap comprising: a female plug terminal formed of a spring contact that is formed integrally with a cord fixing portion to be gripped and that can be compressed and deformed along the axis of the high-pressure cord; The engine hole portion penetrated from the upper surface of the engine head has an engagement recess formed in the inner peripheral surface near the upper end thereof, while the code cap portion is more than the engagement recess. An elastic fixing member fitted to the outer peripheral surface near the female plug terminal from the upper end of the cord cap portion is held, and a locking claw portion of the elastic fixing member disposed corresponding to the engaging recess is provided. A cap for a high-pressure spark plug, wherein a receiving seat that can be engaged with the engaging recess is protruded. 2. The rain cover portion according to claim 1, wherein a concave portion capable of receiving a swinging movement of a distal end portion of the elastic arm portion of the elastic fixing member is formed in the rain cover portion. The cap for a high-pressure spark plug as described. 3. The cord cap portion has a locking ridge protruding on an outer peripheral surface above the receiving seat, and the elastic fixing member has a locking ridge formed on an inner peripheral surface of a cylindrical body portion. 2. The cap for a high-pressure spark plug according to claim 1, wherein an engaging groove engageable with the cap is formed in a concave shape. 4. The cord cap portion has a vertically long lock storage portion projecting from an outer peripheral surface of the code cap portion so that a part of the lock member can be engaged with the engagement recess. The high-pressure ignition plug cap according to claim 1, wherein the cap is formed.