JPH04259779A - Spark plug and manufacture thereof - Google Patents

Abstract

PURPOSE: To provide a spark plug with small size and high durability to the pressure in a combustion chamber by inserting an insulator into a shell from the shell end part on the side of a spark gap whose inner diameter is larger than the outer diameter of the insulator. CONSTITUTION: The end part 110a of an outside shell 110 facing a spark gap 117 has the inner diameter larger than the outer diameter of the most thicker portion of an insulator 106 surrounding a central electrode 101. The insulator 106 is inserted into the shell 110 from the end part of the spark gap 117 side of the shell 110. By this constitution, the seat of the shell 110 is formed in the state of a conical inner surface, and the outer surface of the insulator 106 can be formed in a shape corresponding to the shape of the seat of the shell 110. Thereby, durability to the pressure in a combustion chamber is enhanced and the size is made small.

Description

[Detailed description of the invention]

0001

FIELD OF INDUSTRIAL APPLICATION The present invention provides a method for forming a spark gap between a center electrode, an insulator surrounding the center electrode, an outer shell surrounding at least a portion of the insulator, and the center electrode. and at least one ground electrode arranged in such a manner. The present invention also relates to a method of manufacturing a spark plug of the above type.

0002

BACKGROUND OF THE INVENTION The manufacture of conventional spark plugs, the assembly of the various parts, and the disadvantages associated therewith will now be described. It would be desirable to provide a spark plug that is easy to assemble and therefore inexpensive to manufacture. In addition, regarding durability against pressure in the combustion chamber of the engine,
It is also desirable to improve the construction of conventional spark plugs.

[0003] Up until now, spark plugs have been made in a certain size to fit current international standards and existing engines. There is now a trend among engine manufacturers to require smaller spark plugs that can contribute to advanced engine designs. Accordingly, it would be desirable to provide a spark plug having an overall size smaller than that of known spark plugs.

0004

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a spark plug that can be made smaller than a conventional spark plug and has excellent durability against combustion chamber pressure, and a method for manufacturing the same.

[0005]

[Means for Solving the Problems] The spark plug of the present invention is characterized in that the end of the shell facing the spark gap is
The insulator has an inner diameter larger than the outer diameter of the thickest part of the insulator, and the insulator can be inserted into the shell from the end of the shell on the spark gap side (i.e., the bottom of the shell) (bottom-up type, i.e. (inverted assembly).

A feature of the method for manufacturing a spark plug according to the present invention is that an insulator is inserted into the shell from the end of the shell facing the spark gap. With the construction of the spark plug of the invention, the shell can be provided with an inner annular seat facing the spark gap, and the insulator can be formed to abut said seat of the shell. The abutment of the insulator against said seat of the shell makes it possible under all circumstances to withstand the pressure acting on the insulator from the combustion chamber, and the insulator located inside the shell, the center It can be ensured that the electrodes as well as all other components (core assembly) cannot be unintentionally blown out by the pressure in the combustion chamber.

[0007] This feature of the spark plug according to the invention is such that the different spark plug configurations defined by the different spark plug assemblies (top-down or conventional assemblies) may result in the inadvertent ejection of the core assembly. This is a huge improvement over some conventional spark plugs. In fact, until now, the spark plug was located at the upper end of the shell (
That is, the spark plug is assembled from the outer end of the spark plug when it is installed and used in an engine. Therefore, in conventional spark plugs, the seat of the shell and the shoulder of the insulator face in the opposite direction to the spark plug of the present invention, and additional measures are required to withstand the pressure in the combustion chamber. It is. Experience has shown that conventional top-down assemblies have considerable difficulty in making the additional means sufficiently strong due to their structural limitations.

The shell seat of the spark plug of the present invention is in the form of a generally conical inner surface, and the insulator outer surface can be shaped to correspond to the shape of the shell seat. However, in a preferred embodiment of the invention, the seat of the shell is shaped to abut a shoulder on the insulator. In order to simplify the assembly of the various components of the spark plug in the method of the invention, it is desirable to be able to insert as many components as possible into the shell from the lower end of the shell, for example the center electrode. preferable. This feature has further advantages, which will be discussed below.

The thermal value of a spark plug depends primarily on the depth of the annular space between the insulator and the shell, which generally exists in spark plugs and is open toward the spark gap. It is well known that it is determined based on Heretofore, various designs of insulators and shells have varied the size of the annular space. It has been found that the thermal value of a spark plug can be varied by using a plug with conventional components and by placing a thermally conductive material in a portion of the annular space. The size of the portion of the annular space in which the thermally conductive material is placed determines the thermal value of the plug. “Spark Plug Made of General-Purpose Components” filed by the applicant at the same time as this application
Plugs with Universal Com
A pending US patent application entitled ``Ponents'' describes the use of thermally conductive materials. In the method for manufacturing a spark plug according to the present invention,
Particularly convenient is the use of inserts. This is because the insert can be inserted into the annular space from the lower end of the spark plug.

According to the method of the invention, a non-suppressor type spark plug (spark without a noise suppressor) is manufactured using a cylindrical center electrode that fits snugly within the insulator and extends the entire length of the insulator. plug) can be configured. Alternatively, if a suppressor element is required, a fired-in resistance seal may be used, as detailed below.
A resistive seal may also be provided.

The insulator used in the present invention preferably has a diameter, at least in its outer portion (top), that is significantly smaller than the insulator used in a corresponding conventional plug. However, standard size plugs currently in use may be constructed in accordance with the present invention by using standard size insulators or by adding a collar around a small diameter insulator to provide a standard size.

0012

BRIEF DESCRIPTION OF THE DRAWINGS Other preferred features and advantages of the invention will become apparent from the following description of some preferred embodiments, taken in conjunction with the accompanying drawings. In all drawings to which reference is made below, spark plugs are shown at their "spark gap" or "inner end (lower end)".
It is shown with the "outer end (upper end)" facing up and the "outer end" (upper end) facing up. In addition, all the drawings show a state in which the shell, insulator, and ground electrode are cut to expose internal components.

As first shown in FIGS. 1 and 2, a typical conventional spark plug includes a center electrode 1, a conductor 2 in the form of a rod, a spring 3, and a suppressor 4. , a terminal 5, and an insulator 6. These components are commonly referred to as the spark plug core assembly. The insulator 6 has a central bore 7 for receiving the components 1, 2, 3, 4, 5 mentioned above. The function of these components 1, 2, 3, 4, 5 is well understood by those skilled in the art and will therefore not be described in detail here.

The bore 7 of the insulator 6 is narrower at its lower end than at its upper end, thus forming an upwardly facing seat 8. The center electrode 1 can be engaged with the seat 8.
Its upper end is thickened so that the component can be positioned axially within the bore 7. The center electrode 1 fits snugly into the narrow lower end of the bore 7. As shown in FIG. 2, a space 9 exists between the conductor 2 and the inner surface of the bore 7, and this space 9 is filled with a special powder sealing material (indicated in its entirety by the number 30 in FIG. 1). is filled. This powder sealing material is particularly suitable for the conductor 2 and the center electrode 1.
This is to prevent the objects from moving from their desired positions. The terminal 5 has a narrow lower part 5a,
The lower part 5a is dimensioned to fit snugly into the bore 7 of the insulator 6. The upper part 5b of the terminal 5 is thick,
Both parts 5a, 5b are joined by a downwardly directed shoulder 5c which rests on the upper end of the insulator 6 after assembly.

As described above, since the bore 7 is provided with the seat 8 and the upper end of the center electrode 1 is provided with a thick portion corresponding to the seat 8, the structure of the core assembly is The parts 1, 2, 3, 4, 5 are manufactured in such a way that they can be inserted only from the top of the insulator 6. Also, Figure 1
The conventional spark plug shown in FIG. 2 includes a shell 10 surrounding the lower end of the core assembly. shell 10
As shown in the figure, a seat 12 facing upward is formed,
The seat 12 positions a corresponding shoulder 14 of the insulator 6. Thus, during manufacture, the insulator 6 is inserted into the shell 10 from the top end of the shell 10 as shown. shell 1
A gasket 15 is arranged between the seat 12 of the 0 and the shoulder 14 of the insulator 6. In particular, what should be prevented is the ingress of gases from the combustion chamber of the engine into the spark plug. A ground electrode 16 is attached to the shell 10 and is arranged to form a spark gap 17 with the end of the center electrode 1 protruding from the insulator 6.

The shoulder 14 of the insulator 6 is part of a flange 20 forming the thickest part of the insulator 6. The upper part of the shell 10 is arranged such that a space 18 is formed between the shell 10 and the insulator 6 above the flange 20 of the insulator 6.
It has a shape that can surround the flange 20. shell 1
This space 18 is also filled with a special powder 30 before the folded flange 19 is formed on the upper edge of the 0. The formation of the folded flange 19 confines the powder 30 and completes the assembly of the spark plug.

The above structure of conventional spark plugs has a number of drawbacks. That is, just forming the core assembly requires four so-called powder tamping steps, and assembling the core into the shell 10 requires two additional powder tamping steps. As mentioned above, a particular problem in the manufacture of spark plugs is ensuring that they can withstand the very high gas pressures within the combustion chamber of an engine. This pressure acts on the end of the core assembly facing the spark gap and, as previously described, turns the folded flange 19
If the holding force of the powder in the space 18 is not strong enough, the core assembly may pop out of the shell 10.

As will be understood from the following description, these drawbacks of conventional spark plugs can be overcome by the spark plug of the present invention (more specifically, the insulator 6, which is often a weak point in conventional spark plugs) (by eliminating the appropriate powder between the shell 10 and the folded flange 19). Next, a spark plug according to a first embodiment of the present invention will be described with reference to FIGS. 3 and 4. FIG. 3 and 4, a so-called "non-suppressor" plug is shown. In this plug, the core assembly simply includes a center electrode 101 and an insulator 106.
and a terminal 105.

The insulator 106 has a bore 107 extending along its entire length, the bore 107 having a constant cross-sectional area. The center electrode 101 has a nail-like shape with a shaft 103 and a head 104. The head 104 is connected to the insulator 10 in the assembled plug.
6 is formed with a seat 104a that comes into contact with the lower surface 106a of 6. During assembly, center electrode 101 is inserted into bore 107 of insulator 106 from the lower end of insulator 106 as shown.

The shaft 103 of the center electrode 101 is an insulator 106
is longer than the bore 107 of the insulator 106 after assembly.
protrudes from the upper end of the Terminal 105 is comprised of a cylindrical collar surrounding this protruding end of center electrode 101 . A gasket 109 is arranged between the terminal 105 and the insulator 106, and the gasket 109 is tightly fitted around the axis 103 of the center electrode 101. The purpose of this gasket 109 is to connect the shaft 103 and the insulator 1.
06 and act as a seal against any combustion gases that may escape from the combustion chamber. In the completed plug, the end of shaft 103 is preferably flush with the top surface of terminal 105.

Shell 110 includes a first portion 110a shown at the bottom of the drawing and a second portion 110b shown at the top. The shell 110 has a bore 111 along its length, the diameter of the second portion 110b being smaller than the diameter of the first portion 110a, such that the bore 111 includes an annular seat 112. is formed. Insulator 106 is provided with a flange 120 having an upwardly facing shoulder 113 . According to the manufacturing method of the present invention, during assembly, the insulator 106 is
As shown, the shoulder 113 is located at the seat 11 of the shell 110.
from the lower end of shell 110 until it abuts shell 1
10. Therefore, the inner diameter of the bore 111 in the first portion 110a of the shell 110 must be larger than the outer diameter of the flange 120, which is the thickest part of the insulator 106. A gasket 115 is preferably disposed between the seat 112 and the shoulder 113 to prevent gases from escaping from the combustion chamber. The shell 110 has a lower part (
A flange 119 is provided on the outside of the first part) 110a. This flange 119 is a part that comes into contact with the cylinder head of the engine when the plug is used.

Insulator 106 is retained within bore 111 of shell 110 by any suitable means. One example is a spring washer 114 that holds the insulator 106 against the seat 112 of the shell 110. The spring washer 114 is held within an annular recess formed in the inner surface of the shell 110. Other examples of holding means for the insulator 106 will be described later.

A ground electrode 116 is provided at the lower end of the shell 110.
is attached, and the ground electrode 116 is arranged such that a spark gap 117 is formed between the ground electrode 116 and the head 104 of the center electrode 101. This completes the assembly. It will be appreciated that the spark plugs of FIGS. 3 and 4 can be assembled in several different ways according to the present invention. For example, center electrode 101 can be inserted into insulator 106 either before or after inserting insulator 106 into shell 110. Further, if the terminal 105 and the gasket 109 are clamped concentrically with each other, the center electrode 101 can be inserted through the insulator 106, the gasket 109, and the terminal 105 in one step. Alternatively, gasket 109 and terminal 105 can be removed after inserting center electrode 101 into insulator 106 and inserting insulator 106 into shell 106.
It may be placed at the end of the center electrode 101 before or after insertion into the center electrode 10 .

Ground electrode 116 may be attached to shell 110 before insulator 106 is attached to shell 110, in which case ground electrode 116 may be attached to shell 110, as shown in FIG.
16 in the "straight" position. Alternatively,
A ground electrode 116 may be secured to the shell 110 as a final step, either before or after bending into the shape shown in FIG. As mentioned above, the spark plug explained in relation to FIGS. 3 and 4 has a lower end, that is, an end on the spark gap side (
It is assembled by inserting the individual components into each other (i.e., a bottom-up or inverted assembly), starting from the end that is in the combustion chamber in use. This is a conventional spark plug (top-down or conventional assembly) designed to be assembled by inserting the components from the opposite end (the end that is outside the combustion chamber in use). This is a marked difference.

The spark plug structure shown in FIGS. 3 and 4 has many advantages over conventional structures. The first advantage is a significantly greater ability to withstand the pressure within the combustion chamber of the engine. In fact, the insulator 106 is prevented from being pushed out of the shell 110 because its shoulder 113 abuts the seat 112 of the shell 110. It should be noted that the seat 112 of the shell 110 and the corresponding shoulder 113 of the insulator 106 can be significantly larger than shown. This new construction of the present invention is far more efficient than the specialized powder and folded flange combinations used in prior art spark plugs.

It is further noted that the wall thickness in the area of the smaller bore portion (second portion) 110b of the shell 110 is considerably thicker than the wall thickness of the remainder of the shell 110;
This area can be strengthened. Compared to the folded flange 19 (FIG. 2) of a conventional spark plug, the wall thickness in this region of the spark plug of the present invention is considerably thicker and therefore able to withstand the pressure within the combustion chamber of the engine without failure.

Furthermore, the shoulder (seat) 104 of the center electrode 101
Since point a is in contact with the lower surface of the insulator 106, the center electrode 101 can withstand the pressure inside the combustion chamber that tends to cause it to pop out from the insulator 106. Spring washer 1
The means for retaining the insulator 106 within the shell 110, such as 14, may be of relatively low spring force. this is,
This is because, during use, the insulator 106 will not fall from the shell 110 due to pressure from the combustion chamber. This spring washer 114 is merely for preventing the insulator 106 from coming off when handling the spark plug.

Another advantage of the spark plug of the present invention over conventional spark plugs is that the spark plug of the present invention requires fewer manufacturing steps. This is primarily due to the fact that no special powder is required between the insulator 106 and the shell 110, and therefore no tamping step is required for this powder, and no flange to be folded back is required.

Furthermore, the spark plug shown in FIGS. 3 and 4 has the following characteristics:
It can be manufactured in a small size. Comparing FIG. 2 and FIG. 4, the lower portions of the shells 10 and 110 are substantially the same in both cases, but the upper portion (second portion) 110b of the shell 110 in FIG. 4 is considerably smaller in diameter. The shell 110 of FIG. 4 is designed to be compatible with the same engine that uses the spark plug of FIG. 2, and therefore has the same spark end size. However, for other applications, the diameter of the spark end may be smaller.

Furthermore, the insulator 10 of the spark plug shown in FIG.
The diameter of 6 is smaller than the diameter of the insulator 6 of the spark plug of FIG. 2 over its entire length except for the lower part. A non-suppressor type plug can also be made much shorter than the plug shown in FIG. Because the center electrode 101 is provided with a head 104, a larger sparking surface is obtained than in the spark plug of FIG. This is a good feature because a larger spark surface can extend the life of the spark plug. In fact, small spark surfaces wear out quickly.

Since the diameter of the bore 111 at the bottom of the shell 110 is larger than the diameter at the bottom of the insulator 106, in the assembled plug, the insulator 106 and the shell 11
An annular space 118 exists between 0 and 0. As is well known in the art, by varying the depth X of this annular space 118, the thermal value of the plug can be varied. This is because this annular space 118 forms a heat transfer path from the spark gap 117 to the cylinder head of the engine. Until now, various insulators and/or
Or by providing a shell, the depth X of the annular space 118
Spark plugs with various heat values are manufactured by changing the. A portion of the annular space is filled with a thermally conductive material and the thermally conductive material is brought into intimate contact with the insulator and the shell, as described in the aforementioned U.S. patent application filed concurrently with this application by the applicant. The heat value of an ordinary spark plug can be changed by bringing it into contact with.

The thermal value of the spark plug according to the invention can be conveniently varied in this way. because,
Before the final installation of the ground electrode 116, the annular space 1
This is because the thermally conductive material can be introduced into the annular space 118 from the open end of the annular space 118 . As described in the above-mentioned co-pending U.S. patent application, the thermally conductive material is inserted in the form of a powder, a suitably shaped cylinder, or a helical spring, and these are inserted into the inner surface of the shell and the insulator. Stamped in place to make intimate contact with the outer surface. The thermally conductive material is preferably a metal such as copper.

A second embodiment of the invention is shown in FIGS. 5-8, which differs from the embodiment of FIGS. 3 and 4 except that a thermally conductive material is added. Same as example. 3-8, like parts are designated with like reference numbers. Three spark plugs are shown in FIGS. 6-8, these spark plugs are numbered 130a, 1
The length of the inserts shown at 30b and 130c are the same, and all other features are the same as the spark plug of FIG. In the case of identical plugs, the size of the insert 130 determines the thermal value of the plug. FIG. 5 is an exploded view similar to FIG. 3 for a spark plug with the addition of three different inserts 130a, 130b and 130c. 6-8 illustrate a range from the relatively "hot" plug of FIG. 6 (but not as hot as the plug of FIG. 4) to the "cold" plug of FIG. It is understood that there are The thermally conductive material also serves to hold insulator 106 in place within shell 110.

As previously mentioned, the spark plug insulator 106 shown in FIGS. 4 and 6-8 has a smaller diameter than conventional spark plug insulators. The spark plug of the present invention is preferably configured to fit, for example, existing boot-shaped spark plug connectors, for which purpose the external dimensions of the spark plug of the present invention are the same as those of conventional spark plugs. It is necessary to This is easily achieved according to the invention by using insulators of various sizes. Alternatively, a range of spark plugs may include a general purpose insulator and a collar surrounding its top or exterior (the collar having suitable dimensions to enable the plug to be used in the selected application). ) can be configured according to the present invention.

FIGS. 9 and 10 are an exploded view and a completed cross-sectional view, respectively, of the spark plug provided with the above collar. The same parts as those explained so far are shown in Figures 9 and 1.
0 is also represented by the same reference number. In the spark plugs of FIGS. 9 and 10, the insulator 206 has a straight side surface projecting upward from the shell 110, whereas the insulator 1 of the spark plugs of FIGS.
Figure 5 except that 06 has a ribbed portion.
and the same as the spark plug in FIG. This part is surrounded by collar 230. Collar 230 is shaped to fit snugly around insulator 206 and is similar to conventional spark plug shell 10 shown in FIG.
It has the same external dimensions as the portion of the insulator 6 protruding from the insulator 6. It should be noted that the gasket 209 of the spark plug of FIG. 10 is larger than the gasket 109 of the spark plugs of FIGS. 3-8, allowing it to seal any space between the collar 230 and the insulator 206. It is.

In accordance with the present invention, a range of spark plugs with collars of various sizes for a variety of applications can be manufactured using a universal insulator 206. Collar 230 is preferably made of the same material as insulator 206. All of the spark plugs described above in connection with FIGS. 3-10 are non-suppressor type plugs. However, incorporating a suppressor into a plug constructed in accordance with the present invention is a simple matter. FIG. 11 shows a core assembly with a suppressor suitable for use in the spark plug of the present invention.

The illustrated core assembly includes the insulator 106,
The insulator 306 has the same external dimensions as the insulator 206. However, this insulator 306 is not a constant diameter bore, and the first portion (lower portion) 307a of the bore 307 has a smaller diameter than the second portion 307b. Therefore, both parts 30
A seat 311 is formed between 7a and 307b, the function of which will be described later.

The core assembly includes a center electrode 301 having a shaft 303 and a head 304 that abuts the lower surface of an insulator 306 . axis 303
terminates just above the seat 311 of the insulator 306. During assembly, the center electrode 301 is connected from the lower end of the insulator 306 (i.e., the end on the spark gap side) to the insulator 306.
It is inserted into 06.

The core assembly shown in FIG. 11 further includes a suppressor seal 312, which will be described in more detail below, and a conductor 302.
It has a terminal 305 and a gasket 309. Terminal 305 and conductor 302 can be integrally molded. Alternatively, the terminal 305 can be comprised of a collar that fits onto the end of the conductor 302, as shown by the dashed line. Conductor 302 is inserted into insulator 306 from above.

Before inserting the conductor 302, a small amount of glass-metal powder as a suppressor is poured into the upper base (second part) 307b of the insulator 306. This causes the glass-metal powder to cover the end of the center electrode 301 and fill the space between the center electrode 301 and the bore 307. After inserting the terminal 305 and conductor 302, the core assembly is flame heated to melt the glass-metal powder and form the semiconductor. Upon subsequent cooling, the semiconductor forms a suppressor element 312 for sealing any space between the center electrode 301 and the insulator 306 and for suppressing radio frequency interference. This suppressor element 312 replaces the spring 3 and suppressor 4 used in the conventional spark plug shown in FIGS. 1 and 2.

Gasket 309 serves to hold terminal 305 and conductor 302 in place and
The remaining space between 02 and insulator 306 is sealed. Gasket 309 connects terminal 305 and conductor 302
may be attached to the core assembly at any suitable point, depending on whether the element is an integral or separate element. If desired, terminal 305, or a portion thereof, can be configured to have the same shape as terminal 5 of FIG. 2, thereby allowing terminal 305 to extend into bore 307 and preventing movement of conductor 302. Good too.

[Brief explanation of the drawing]

[Fig. 1] Components of a spark plug according to the prior art:
It is an exploded view showing a part of them in cross section.

2 is a partial cross-sectional view of a spark plug assembled from the components of FIG. 1; FIG.

FIG. 3 is an exploded view showing some of the components of the spark plug according to the first embodiment of the present invention in cross section.

4 is a partial cross-sectional view of a spark plug assembled from the components of FIG. 3; FIG.

FIG. 5 is an exploded view showing some of the components of a spark plug according to a second embodiment of the present invention in cross section.

6 is a partial cross-sectional view of one of the three spark plugs assembled from the components shown in FIG. 5; FIG.

FIG. 7 is a partial cross-sectional view of another of the three spark plugs assembled from the components shown in FIG. 5;

8 is a partial sectional view showing still another spark plug of the three spark plugs assembled from the components shown in FIG. 5. FIG.

FIG. 9 is an exploded view showing some of the components of a spark plug according to a third embodiment of the present invention in cross section.

FIG. 10 is a partial cross-sectional view showing a spark plug assembled from the components shown in FIG. 9;

FIG. 11 is a partial sectional view showing a core assembly of a spark plug according to a fourth embodiment of the present invention.

[Explanation of symbols]

101 Center electrode 103 Center electrode axis 104 Center electrode head 104a Center electrode seat 105 Terminal 106 Insulator 106a Insulator bottom surface 107 Insulator bore 109 Gasket 110 Shell 110a Shell first portion 110b Shell second portion 111 Shell bore 112 Shell seat 113 Insulator shoulder 114 Spring washer 115 Gasket 116 Ground electrode 117 Spark gap 118 Annular space 119 Shell flange 120 Insulator flange 130a Insert 130b Insert 130c Insert 206 Insulator 209 Gasket 230 Collar 301 Center electrode 302 Conductor 303 Center electrode shaft 304 Center electrode head 305 Terminal 306 Insulator 307 Bore 307a First portion of bore 307b Second portion of bore 309 Gasket 312 Suppressor (noise suppressor, suppressor element)

Claims (23)

[Claims] Claim 1: A center electrode (101);
an insulator (106) surrounding the insulator (101);
an outer shell (110) surrounding at least a portion of the outer shell (110);
) and the center electrode (101).
at least one ground electrode (116) arranged to form a spark gap (117);
The end (110a) of the insulator (106) has an inner diameter larger than the outer diameter of the thickest point of the insulator (106), and the insulator (106) is connected to the spark gap side of the shell (110). A spark plug characterized in that it can be inserted into the shell (110) from its end. 2. The shell (110) comprises a generally annular seat (112) facing a spark gap (117).
Claim 1, wherein the insulator (106) has a shape that allows it to come into contact with the seat (112).
Spark plugs listed in. 3. The seat (112) and the insulator (106,
The spark plug according to claim 2, characterized in that a seal (115) is arranged between the spark plug and the spark plug (113). 4. The center electrode (101) is connected to the shaft (103).
), and the end of the shaft (103) on the spark gap side has a head (
104) is provided.
3. The spark plug according to any one of 3. 5. A portion of the insulator (206) is attached to the shell (110) in a direction away from the spark gap (117).
Spark plug according to any one of the preceding claims, characterized in that it extends beyond the collar (230) and is surrounded by a collar (230). 6. The center electrode (101) protrudes from the insulator (106) in a direction away from the spark gap, and the center electrode (101)
Spark plug according to any one of the preceding claims, characterized in that it further comprises a terminal (105) in the form of a collar surrounding the projecting end of the spark plug. 7. Spark plug according to claim 1, characterized in that the center electrode (101) is connected to a terminal via a suppressor element. 8. The suppressor element includes an electrode (
Spark plug according to claim 7, characterized in that it is in the form of a seal (312) covering the end of the spark plug (301). 9. Spark plug according to claim 7, characterized in that a conductor (302) extends between the suppressor element and the terminal. 10. The conductor (302) projects from the insulator (306) in a direction away from the spark gap, and the conductor (302) is in the form of a collar surrounding the projecting end of the conductor (302). Terminal (3)
The spark plug according to claim 9, further comprising: 05). 11. The terminal (305) is a conductor (
10. The spark plug according to claim 9, wherein the spark plug is integral with the spark plug (302). 12. The insulator (106) and the shell (1
There is an annular space (118) open toward the spark gap (117) between the insulator (10) and the insulator (10).
12. Spark according to any one of the preceding claims, further comprising retaining means arranged in the annular space (118) for retaining the spark (106) in the shell (110). plug. 13. Claim 12, characterized in that the holding means comprises an annular spring washer (114).
Spark plugs listed in. 14. The insulator (106) and the shell (1
10), there is an annular space (118) open toward the spark gap (117), and a part of the annular space (118) includes an insulator (106) and a shell (110). Spark plug according to any one of the preceding claims, characterized in that it is filled with a thermally conductive material (130) arranged in intimate contact with the spark plug. 15. Spark plug according to claim 14, characterized in that the thermally conductive material (130) consists of a powder. 16. Spark plug according to claim 14, characterized in that the thermally conductive material (130) consists of a cylindrical body. 17. Spark plug according to claim 14, characterized in that the thermally conductive material (130) consists of a helical spring. 18. Any one of claims 14 to 17, characterized in that the thermally conductive material (130) is metal.
Spark plugs listed in section. 19. Spark plug according to claim 14, characterized in that the thermally conductive material (130) is copper. 20. A spark plug substantially the same as described in connection with any of FIGS. 3-11 of the accompanying drawings. 21. A generally cylindrical insulator (106
), providing the insulator (106) with a shell (110) surrounding at least a portion thereof, and creating a spark gap between the center electrode (101). arranging a ground electrode (116) to form a spark gap (117).
A method for manufacturing a spark plug, characterized in that it is inserted into the shell (110) from a). 22. According to claim 21, the center electrode (101) is inserted into the insulator (106) from the end of the insulator (106) facing the spark gap (117). spark plug manufacturing method. 23. The insulator (106) and the shell (1
An annular space (118) that is open toward the spark gap (117) is provided between the annular space (10) and a thermally conductive material (
23. The spark plug according to claim 21 or 22, wherein a spark plug (130) is inserted.