Description:Complete Specification

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001] This invention relates to a bore that is defined in an insulator of a spark plug, and more specifically to the bore that is defined in the insulator of the spark plug that is adapted to receive an electrode therein.

Background of the invention
[0002] US 2006220512 AA describes a spark plug requiring low discharge voltage and having high self-cleaning capability. A spark plug according to the present invention includes a metal shell, an insulator retained in the metal shell, a center electrode secured in the insulator, and a ground electrode. The center electrode includes a base member and a thin member thinner the base member The ground electrode includes a base member fixed to the metal shell and a protruding member that protrudes from the base member and has an end face with an inner and an outer edge. When the insulator is clean, sparks can be discharged between the thin member and the inner edge. When the insulator is fouled with carbon, sparks can be discharged between the base member and the outer edge to self-clean the insulator. Dimensional parameters and relationships are specified in the spark plug, so that the spark plug can induce spark discharges with a low discharge voltage while securing an excellent self-cleaning capability thereof.

Brief description of the accompanying drawing
[0003] Figure 1 illustrates a drawing depicting a bore that is defined in the insulator of the spark plug that is adapted to receive an electrode therein.

Detailed description of the embodiments
[0004] Figure 1 illustrates a spark plug 100 in one embodiment of the invention. The spark plug 100 comprises an insulator 120 extending along a longitudinal length of the spark plug 100, the insulator 120 positioned within a housing 140 of the spark plug 100. An electrode 160 is positioned within a bore 180 extending along the longitudinal length of the spark plug 100. The electrode 160 comprises a flange shaped portion 115 defined on a body of the electrode 160, wherein the flange shaped portion 115 defined on the body of the electrode 160 is inserted within a groove 125 defined within the insulator 120 and secured within the groove 125 defined within the insulator 120.

[0005] Figure 1 illustrates a spark plug 100 in one embodiment of the invention. The spark plug 100 comprises an insulator 120 extending along a longitudinal length of the spark plug 100 and is positioned within the housing 140 of the spark plug 100. More specifically, the insulator 120 extends from one end of the spark plug 100 and culminates proximate to a first electrode of the spark plug 100. More specifically, the insulator 120 is separated from the first electrode of the spark plug 100 by a spark gap that is defined between the insulator 120 and the first electrode of the spark plug 100. In an exemplary embodiment, the second electrode 160 is positioned within the bore 180 extending along the longitudinal length of the spark plug 100 and extends between a small displacement from the first electrode and culminating at a displacement from the opposing end of the insulator 120. The second electrode 160 comprises the flange shaped portion 115 defined on a body of the second electrode 160 and adjacent to the end of the second electrode 160. The flange shaped portion 115 defined on the body of the second electrode 160 and adjacent to the end of the second electrode 160 is inserted within a groove defined within the insulator 120 and secured within the groove defined within the insulator 120. More specifically, the flange shaped portion 115 defined on the body of the second electrode 160 and adjacent to the end of the second electrode 160 that is inserted within the groove defined within the insulator 120 and secured within the groove defined within the insulator 120 facilitates preventing sparks from emanating from the flange shaped portion 115 defined on the body of the second electrode 160 and crossing over to the insulator 120. This is because the triple point (air/metal/insulator interface) is shifted away from the flange shaped portion 115 that is positioned within the insulator 120.

[0006] In an exemplary embodiment, the flange shaped portion 115 defined on the body of the second electrode 160 is partially inserted within the groove 125 defined within the insulator 120 such that the groove 125 defined within the insulator 120 partially circumscribes the flange shaped portion 115 defined on the body of the second electrode 160. Therefore, in this embodiment of the invention, the flange shaped portion 115 defined on the body of the second electrode 160 that is partially inserted within the groove 125 that is defined within the insulator 120 does not spark in the flange shaped portion 115 defined on the body of the second electrode 160 that is partially inserted within the groove 125 that is defined within the insulator 120. This is because the triple point (air/metal/insulator interface) is shifted away from the flange shaped portion 115 that is positioned within the insulator 120 to the flange shaped portion 115 that is located outside the insulator 120. In an alternate exemplary embodiment, the flange shaped portion 115 defined on the body of the second electrode 160 is completely inserted within the groove 125 defined within the insulator 120 such that the groove 125 defined within the insulator 120 completely circumscribes the flange shaped portion 115 defined on the body of the second electrode 160. Therefore, in this embodiment of the invention, the flange shaped portion 115 defined on the body of the second electrode 160 that is completely inserted within the groove 125 that is defined within the insulator 120 does not spark in the flange shaped portion 115 defined on the body of the second electrode 160 that is completely inserted within the groove 125 that is defined within the insulator 120. This is because the triple point (air/metal/insulator interface) is shifted away from the flange shaped portion 115 that is positioned within the insulator 120 to the metal portion of the second electrode 160 that is located outside the insulator 120.

[0007] In yet another alternate exemplary embodiment, the flange shaped portion 115 defined on the body of the second electrode 160 is inserted within the groove 125 defined within the insulator 120 such that the groove 125 defined within the insulator 120 circumscribes the flange shaped portion 115 defined on the body of the second electrode 160 to a depth that prevents electric sparks emanating from the flange shaped portion 115 defined on the body of the second electrode 160. Therefore, in this embodiment of the invention, the flange shaped portion 115 defined on the body of the second electrode 160 that is inserted within the groove 125 that is defined within the insulator 120 such that the groove 125 defined within the insulator 120 circumscribes the flange shaped portion 115 defined on the body of the second electrode 160 to a depth that prevents electric sparks emanating from the flange shaped portion 115 defined on the body of the second electrode 160 does not spark in the flange shaped portion 115 defined on the body of the second electrode 160. This is because the triple point (air/metal/insulator interface) is shifted away from the flange shaped portion 115 that is positioned within the insulator 120 to the flange shaped portion 115 that is located outside the insulator 120.

[0008] It must be understood that the embodiments explained above are only illustrative and do not limit the scope of the disclosure. Many modifications in the embodiments with regard to dimensions of various components are envisaged and form a part of this invention. The scope of the invention is only limited by the scope of the claims.
, Claims:We Claim

1. A spark plug (100), said spark plug (100) comprising:
an insulator (120) extending along a longitudinal length of said spark plug (100), said insulator (120) positioned within a housing (140) of said spark plug (100); and
an electrode (160) positioned within a bore (180) extending along the longitudinal length of said spark plug (100), said electrode (160) comprising a flange shaped portion (115) defined on a body of said electrode (160), wherein the flange shaped portion (115) defined on the body of said electrode (160) is inserted within a groove (125) defined within said insulator (120) and secured within the groove (125) defined within said insulator (120).

2. The spark plug (100) in accordance with Claim 1, wherein the flange shaped portion (115) defined on the body of said electrode (160) is partially inserted within the groove (125) defined within said insulator (120) such that the groove (125) defined within said insulator (120) partially circumscribes the flange shaped portion (115) defined on the body of said electrode (160).

3. The spark plug (100) in accordance with Claim 1, wherein the flange shaped portion (115) defined on the body of said electrode (160)
is completely inserted within the groove (125) defined within said insulator (120) such that the groove (125) defined within said insulator (120) completely circumscribes the flange shaped portion (115) defined on the body of said electrode (160).

4. The spark plug (100) in accordance with Claim 1, wherein the flange shaped portion (115) defined on the body of said electrode (160) is inserted within the groove (125) defined within said insulator (120) such that the groove (125) defined within said insulator (120) circumscribes the flange shaped portion (115) defined on the body of said electrode (160) to a depth that prevents electric sparks emanating from the flange shaped portion (115) defined on the body of said electrode (160).