Spark plug

Abstract

A spark plug having a center conductor, an insulator surrounding the center conductor, a body surrounding the insulator, and a center electrode connected in an electrically conductive manner to the center conductor, wherein the center electrode delimits a spark gap with its front face. The spark plug has two bar-shaped ground electrodes that are connected in an electrically conductive manner to the body, that delimit the spark gap, and that are adjacent to one another and spaced apart from one another in the region of the spark gap.

Claims

1. A spark plug having a center conductor, an insulator surrounding the center conductor, a body surrounding the insulator, and a center electrode connected in an electrically conductive manner to the center conductor, the center electrode delimits a spark gap with its front face, wherein the spark plug has two bar-shaped ground electrodes that are connected in an electrically conductive manner to the body, that delimit the spark gap, and that run next to one another and are spaced apart from one another in the region of the spark gap, wherein when viewed in a plan view of the front face of the body, at least sections of the two ground electrodes located in the region of the spark gap are adjacent to and spaced apart from an imaginary line that runs through the center of the front face of the center electrode and is transverse to the center conductor.

2. The spark plug according to claim 1, wherein at least sections of the two ground electrodes located in the region of the spark gap are parallel to one another.

3. The spark plug according to claim 1, wherein at least a section of each of the ground electrodes located in the region of the spark gap is transverse to the center conductor.

4. The spark plug according to claim 1, wherein each of the two ground electrodes has a flat surface section that delimits the spark gap.

5. The spark plug according to claim 1, wherein each of the two bar-shaped ground electrodes extends in a straight line.

6. The spark plug according to claim 1, wherein the spacing between the two ground electrodes in the region of the spark gap is greater than the spacing from each of the ground electrodes to the front face of the center electrode.

7. The spark plug according to claim 1, wherein the ground electrodes are each composed of a precious metal rod.

8. The spark plug according to claim 1, wherein both ground electrodes are attached to the front face of the body and the attachment points are located opposite one another on the front face of the body.

9. The spark plug according to claim 1, wherein the body projects past the front face of the center electrode.

10. A spark plug having a center conductor, an insulator surrounding the center conductor, a body surrounding the insulator, and a center electrode connected in an electrically conductive manner to the center conductor, the center electrode delimits a spark gap with its front face, wherein the spark plug has two bar-shaped ground electrodes that are connected in an electrically conductive manner to the body, that delimit the spark gap, and that run next to one another and are spaced apart from one another in the region of the spark gap, wherein both ground electrodes are attached to the front face of the body and the attachment points are located opposite one another on the front face of the body.

11. The spark plug according to claim 10, wherein each of the ground electrodes sits in a groove located on the front face of the body.

12. The spark plug according to claim 10, wherein at least sections of the two ground electrodes located in the region of the spark gap are parallel to one another.

13. The spark plug according to claim 10, wherein at least a section of each of the ground electrodes located in the region of the spark gap is transverse to the center conductor.

14. The spark plug according to claim 10, wherein when viewed in a plan view of the front face of the body, at least sections of the two ground electrodes located in the region of the spark gap are adjacent to and spaced apart from an imaginary line that runs through the center of the front face of the center electrode and is transverse to the center conductor.

15. The spark plug according to claim 10, wherein each of the two ground electrodes has a flat surface section that delimits the spark gap.

16. The spark plug according to claim 10, wherein each of the two bar-shaped ground electrodes extends in a straight line.

17. A spark plug having a center conductor, an insulator surrounding the center conductor, a body surrounding the insulator, and a center electrode connected in an electrically conductive manner to the center conductor, the center electrode delimits a spark gap with its front face, wherein the body projects past the front face of the center electrode, wherein the spark plug has two bar-shaped ground electrodes that are connected in an electrically conductive manner to the body, that delimit the spark gap, and that run next to one another and are spaced apart from one another in the region of the spark gap.

18. The spark plug according to claim 17, wherein at least one adjusting recess for adjusting the electrode spacing is located at the front face of the body, permitting access to the spark gap in a direction perpendicular to the center conductor.

19. The spark plug according to claim 18, wherein the direction in which the spark gap is accessible through the adjusting recess is transverse to one of the ground electrodes.

Description

DRAWINGS

(1) Preferred exemplary embodiments of the invention will hereinafter be described in conjunction with the appended drawings, wherein like designations denote like elements, and wherein:

(2) FIG. 1 shows a side view, cross-sectional on one side, of an exemplary spark plug;

(3) FIG. 2 shows a plan view from below of the front face of the body of the spark plug from FIG. 1; and

(4) FIG. 3 shows a perspective view of the spark plug from FIG. 1.

DESCRIPTION

(5) The spark plug 1 shown in the figures has a body 2 with a thread 3 at its front end with which the spark plug 1 is screwed into a cylinder head, not shown, of a stationary, gas-powered internal combustion engine. The spark plug 1 includes a center conductor 4 that is surrounded by an insulator 5. The insulator sits in a passage of the body 2 and is surrounded by the body 2. The insulator 5 projects out of the body 2 at the back end. There, the center conductor 4 projects from the insulator and can be supplied with ignition voltage in a manner known per se via terminal devices that are not shown. The spark plug 1 has a center electrode 6 that is connected in an electrically conductive manner to the center conductor 4 and that delimits a spark gap 10 with its front face 7; see dimension 10 in FIG. 1. The center electrode 6 can have a precious metal reinforcement at its front face 7, for example in the form of a welded-on round blank made of iridium or platinum.

(6) The spark plug 1 has two bar-shaped ground electrodes 11 and 12, each consisting of a precious metal rod. The ground electrodes 11, 12 each run in a straight line and transversely to the center conductor 4, and are also parallel to one another. The two ground electrodes 11, 12 are connected in an electrically conductive manner to the body 2 and delimit the spark gap 10. The two ground electrodes 11, 12 run next to one another and are spaced apart from one another in the region of the spark gap 10. The spacing between the two ground electrodes 11, 12 is labeled in FIG. 2 with the dimension 14, which is 0.4 mm, for example. The spacing 14 is greater than the spacing 10 (spark gap) from each of the ground electrodes 11, 12 to the front face 7. It is evident from the plan view in FIG. 2 that the two ground electrodes 11, 12 run spaced apart from one another next to an imaginary line 16, which is shown as a dotted-and-dashed line and which is perpendicular to the center conductor 5 through the center of the front face 7 of the center electrode 6. At the same time, the imaginary line 16 runs through the center of the spark plug 1.

(7) The body 2 has at its forward end a front face 18 that projects past the front face 7 of the center electrode 5. Located at the front face 18 are two grooves 21, 22 arranged opposite one another and two adjusting recesses 23, 24 arranged opposite one another. The ground electrode 11 sits in the groove 21 and is welded to the body 2 there. The ground electrode 12 sits in the groove 22 and is welded to the body 2 there. The grooves 21, 22 represent attachment points for the ground electrodes 11, 12, which are located on opposite sides of the front face 18 from one another. The adjusting recesses 23, 24 permit access to the spark gap 10 in a direction perpendicular to the center conductor 4 that is also transverse to the ground electrodes 11, 12. The adjusting recesses are used for setting, in particular adjusting, the electrode spacing in the region of the spark gap; see dimension 10 in FIG. 1.

(8) It is to be understood that the foregoing is a description of one or more preferred exemplary embodiments of the invention. The invention is not limited to the particular embodiment(s) disclosed herein, but rather is defined solely by the claims below. Furthermore, the statements contained in the foregoing description relate to particular embodiments and are not to be construed as limitations on the scope of the invention or on the definition of terms used in the claims, except where a term or phrase is expressly defined above. Various other embodiments and various changes and modifications to the disclosed embodiment(s) will become apparent to those skilled in the art. All such other embodiments, changes, and modifications are intended to come within the scope of the appended claims.

(9) As used in this specification and claims, the terms for example, e.g., for instance, such as, and like, and the verbs comprising, having, including, and their other verb forms, when used in conjunction with a listing of one or more components or other items, are each to be construed as open-ended, meaning that the listing is not to be considered as excluding other, additional components or items. Other terms are to be construed using their broadest reasonable meaning unless they are used in a context that requires a different interpretation.

LIST OF REFERENCE NUMERALS

(10) 1 spark plug 2 body 3 thread 4 center conductor 5 insulator 6 center electrode 7 front face 10 spark gap 11 ground electrode 12 ground electrode 16 imaginary line 18 front face 21 groove 22 groove 23 adjusting recess 24 adjusting recess