GB2280932A

GB2280932A - Spark plug electrode

Info

Publication number: GB2280932A
Application number: GB9316970A
Authority: GB
Inventors: Edward Kelly
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-08-14
Filing date: 1993-08-14
Publication date: 1995-02-15
Anticipated expiration: 2013-08-14
Also published as: GB2280932B; GB9316970D0

Abstract

The electrode 6 vibrates in use to an extent determined by a sleeve 5. The free end of the electrode 6 may be a frusto-conical plate (Figs. 5 to 7) arranged outwardly or inwardly of an annular earth electrode. The electrode 6 may abut the sleeve 5 prior to vibration. <IMAGE>

Description

SPARKING PLUG WITH FLEXIBLE ELECTRODE OR ELECTRODES This invention relates to a sparking plug with at least one flexible electrode which furnishes a moving spark of fixed or varying spark gap.

A sparking plug is a well known device fixed into the combustion chamber of (mainly, but not exclusively) an internal combustion engine, generally, by means of a screw thread and sealing washer. It is comprised of the electrically insulated electrodes between which an electric spark is produced to ignite the fuel-air mixture being burned. It facilitates the inspection, servicing and renewal of the electrodes when they become inefficient through electrolitic erosion and/or the deposits from spent fuel.

According to the present invention there is provided a sparking plug with an electrode which is flexible and able to resonate, vibrate, gyrate or precess constrainedly, when it is excited or agitated by the inherant vibrations of its engine or other apparatus to which it is dedicated. This resonating electrode is geometrically shaped and positioned in relation to its opposite electrode so as to cause the spark to move or, move and change its effective spark gap size, (thus changing the length of the spark). The movement of the spark not only promotes spark plug life by distributing the electrolitic erosion over an increased surface area, but also improves ignition by passing the spark through an increased number of fuel molecules than is possible with a stationary spark under the same "in-cylinder" prevailing conditions of favourable fuel turbulence.This later feature can facilitate the use of a lower fuel to higher air (leaner mix) ratio.

Three specific embodiments of the invention will now be described by way of examples with reference to the accompanying drawings, (three embodiments of the invention are of necessity being described here since a proliferation of hybrid configurations of this invention will become apparent to anyone skilled in the art).

Embodiments Number One: Figure 1 shows a cross sectional view through the sparking plug. Referring to the drawing, Fig. 1. Sparking Plug comprises a threaded body 1 to which is attached - by brazing or welding etc. a bi-arcuate electrode 7. Along the axis of the threaded body I is provided an electrode 6. which is sealed inside the spark plug by the insulating ceramic 2 with its exposed end free to vibrate or resonate within the constraints of the restricting sleeve 5, space 4 is a gap (between electrode 6 and connector 3) usually incorporated for safety reasons.

Figure 2. shows part sectional view with inset section showing shape through resonating portion of the electrode.

Figure 3. clarifies shape of resonating electrode with additional inset section.

Figure 4. shows view on both of the electrodes and illustrates the two extreme positions of the resonating electrode together with the bi-arcuate geometric construction which provides a constant optimised spark gap. The resonating electrode although free in its resonating plane is fixed in its perpendicular plane. Thus maintaining its optimised design spark gap.

The moving spark provided by this sparking plug improves ignition by passing the spark through a greater number of fuel molecules than is possible with a stationery spark. It distributes electrolitic erosion over an increased surface area. Since ignition is improved the deposits from spent fuel are reduced and cleaner emissions are exuded from the exhaust.

Embodiment Number Two: Figure 5. shows a cross sectional view through the sparking plug. Referring to the drawing Fig. 5. comprises a threading body 1 to which is attached by brazing or welding etc., a conically surfaced electrode 7. Along the axis of the threaded body 1 is provided an electrode 6 having a conical surface as shown, which is free to gyrate or precess within the constraints of the restricting sleeve 5.

Fig. 6. shows positions of maximum and minimum spark plug gap. The spark gap provided by this sparking plug is compromised ie. it has maximum spark gap which (when functioning) occurs when the axis of the gyrating electrode coincides with the axis of the conical area on the other electrode. The minimum spark gap occurs when the gyrating electrode 6 is in contact with the restricting sleeve 5. As the electrode 6 gyrates the spark (seeking the shortest distance between the two electrodes 6 and 7) moves around the annular space (gap) between them. This conical orientation of the electrodes not only distributes electrolitic erosion over an increased surface area to prolong functional life but also projects the moving spark away from the spark plug offering improved access to the turbulent fuel.

Figure 7. shows a variation of this orientation with a design which renders the precessing electrode harmlessly captive, should it fatigue fracture whilst in service.

Embodiment Number Three: Figure 8. shows a cross sectional view through the sparking plug, referring to the drawing. Fig. 8. Spark Plug comprises a threaded body 1 to which is attached by brazing or welding etc. an arcuate electrode 7. Along the axis of the threaded body 1 is provided an electrode 6 fixed inside the sparking plug insulation ceramic 2 also along the axis is provided a connector 3, a gap 4 may be provided between the electrode 6 and the connector 3 for safety or other technical reasons, as current standard practice.

Figure 9. shows part sectional view with inset section.

Figure 10. shows electrode 6 with inset section to clarify its constructitn.

Figure 11. shows geometric layout of the electrodes. The electrode 7 being constructed from a single arc, the centre of which is offset from (the axis of the spark plug) as shown. Along the perpendicular centre line to the direction of movement of the resonating electrode. Thus providing a minimum spark gap at the constrained ends of the resonate stroke, and a maximum spark gap in mid stroke. (The converse is the case if the springing centre of the single arc is off set to the opposite side of the perpendicular centre line from the position shown.

Claims

1. A sparking plug with one or more flexible electrodes'which reasonate, tremble, vibrate, oscillate, gyrate or precess constrainedly when excited by the vibrations or similar agitations inherant within the engine, or other apparatus to which the sparking plug is affixedly dedicated.

2. A sparking plug as in Claim 1. which provides a moving spark of constrained gap size.

3. A sparking plug as in Claim 1. which provides a random, anularly moving spark of varying (but constrained within design limits) spark gap size.

4. A sparking plug as in Claim 1. which provides a moving spark of cyclically changing (but constrained) spark gap size.

5. A sparking plug as in Claim 3. with a resonating electrode which will remain harmlessly captive, in the event of it sustaining an "in service" fatigue (or other) fracture.

6. A sparking plug as in claim 3. which provides a projected spark which is extraneous to the envelope volume occupied by the sparking plug, throughout the full 360 degree annular movement of the moving spark, ie.

spark takes place outside the solid of revolution defined by the physical components of the sparking plug.

7. A sparking plug as in claims 1., 2., 3., 4., 5. and 6. which has a prolonged functional life since its moving spark distributes the electrolite erosion over a greater surface area than is possible with a stationary spark.

8. A sparking plug as in Claims 1., 2., 3., 4., 5., 6. and 7. which provides improved ignition by passing its (moving) spark through a greater number of fuel molecules than is possible with a stationary spark of the same magnitude.

9. A sparking plug as in Claim 8. which facilitates the use of a "leaner" fuel air ratio, ie. more air per less fuel.

10. A sparking plug as in Claims 1., 2., 3., 4., 5., 6., 7., 8. and 9.

which causes the engine (or other apparatus to which it is affixedly dedicated) to discharge "cleaner", less toxic, exhaust gas emission.

11. A sparking plug as in Claims 1., 2., 3., 4., 5., 6., 7., 8., 9. nd 10. which improves specific fuel consumption and general performance of an internal combustion engine, when compared with a conventional sparking plug with a stationary spark.

12. A sparking plug substantially as described herein with reference to Figs. 1 to 11 of the accompanying drawings.

Amendments to the claims have been filed as follows 1. A sparking plug with one or more flexible electrodes'which resonate.

tremble, vibrate, oscillate. gyrate or precess constrainedly when excited by the vibrations or similar agitations inherant within the engine. or other apparatus to which the sparking plug is affixedly dedicated.

3. A sparking plug as in Claim 1. which provides a random. annularly moving spark of varying (but constrained within design limits) spark gap size.

4. A sparking plug as in Claim 1. which provides a noving spark of cyclically changing (but constrained) spark gap size.

5. A sparking plug as in Claim 3. with a resonating electrode which will remAin harmlessly captive. in the event of it sustaining an "in service' fatigue (or other) fracture.

6. A sparking plug as in claim 3. which provides a projected spark which is extraneous to the envelope volume occupied by the sparking plug.

throughout the full 360 degree annular movement of the moving spark. ie.

spark takes place outside the solid of revolution defined bv the physical components of the sparking plug.

7. A sparking plug as in claims 1. 2.. 3.. 4.. 5. and 6. which has 2 prolonged functional life since its moving spark distributes the electrolitic erosion over a greater surface area than is possible with a stationary spark.

8. A sparking plug as in Claims 1.. 2.. 3.. 4., 5.. 6. and 7. which provides improved ignition by passing its (moving) spark through a greater number of fuel molecules than is possible with a stationary spark of the same magnitude.

10. A sparking plug as in Claims 1., 2., 3., 4.. 5.. 6., 7., 8. and 9.

which causes the engine (or other apparatus to which it is affixedly dedicated) to discharge "cleaner", less toxic. exhaust gas emission.

11. A sparking plug as in Claims 1.. 2.. 3.. 4.. 5.. 6., 7.. 8., 9. and 10. which improves specific fuel consumption and general performance of an internal combustion engine. when compared with a conventional sparking plug with a stationary spark.