DE102021209803A1 - Spark plug unit for hydrogen ignition in an internal combustion engine - Google Patents

Abstract

The present invention relates to a spark plug unit (1) for hydrogen ignition in an internal combustion engine, having a center electrode (2), a ground electrode (4), the center electrode (2) and the ground electrode (4) being set up to generate an ignition spark in an ignition area ( 6), wherein the spark plug unit (1) has a fluid compartment unit (8) which is set up to collect a fluid occurring at the center electrode (2) and/or at the ground electrode (4), in particular a condensate and/or a reaction product, derive from the ignition area (6).

Description

State of the art

The present invention relates to a spark plug unit for hydrogen ignition in an internal combustion engine and a motor vehicle.

There are currently a large number of different types of spark plugs for hydrogen injection and their ignition. The combustion of hydrogen produces water as a product, which can condense on cold surfaces. After a hydrogen-powered engine has been switched off, condensate can collect in the area of the combustion chamber and, under certain circumstances, freeze in cold ambient temperatures. These deposits in the form of ice can lead to problems when restarting and when the engine is running.

Increasing competition in the field of hydrogen vehicles is also putting pressure on costs, so that cheaper vehicle components are in greater demand.

Disclosure of Invention

The spark plug unit according to the invention for hydrogen ignition in an internal combustion engine with the features of claim 1 has the advantage over the known that fluids or condensates arising in the combustion chamber, in particular on the spark plug, can be drained off with the aid of the fluid drain unit, and thus an ignition spark can be formed unhindered. In addition to water, other condensates or water that has been blown in can also be guided out of the ignition area of the spark plug unit in a targeted manner by means of the fluid discharge unit. In addition, the simple manufacture of the fluid discharge unit in the spark plug unit makes it possible to provide a particularly cost-effective means of improving the operating properties of the internal combustion engine.

According to the invention, this is achieved in that the spark plug unit for hydrogen ignition in an internal combustion engine has a center electrode and a ground electrode, the center electrode and the ground electrode being set up to form an ignition spark in an ignition area, and the spark plug unit having a fluid discharge unit set up for this purpose , to drain a fluid occurring at the center electrode and/or at the ground electrode, in particular a condensate and/or a reaction product, from the ignition area.

In other words, the spark plug unit includes a center electrode and a ground electrode, which are arranged in a predetermined position with respect to one another. Furthermore, the spark plug unit includes a fluid drain unit, which can drain a condensate and/or a reaction product or any form of fluid that may occur at the center electrode and/or at the ground electrode. Furthermore, the center electrode and the ground electrode are set up to form, generate and/or allow an ignition spark to form in an ignition area. In particular, the fluid discharge unit can discharge, remove and/or divert the occurring fluid, condensate and/or reaction product from the ignition area of the center electrode and the ground electrode.

The dependent claims show preferred developments of the invention.

Preferably, the fluid drain unit includes at least one hole for draining the fluid in the center electrode and/or in the ground electrode.

One advantage of this embodiment can be that the bore can be used to provide a means that is simple to manufacture in order to be able to drain off any fluids at the center electrode and/or the ground electrode. In other words, the fluid drain unit includes one or more bores in the center electrode and/or the ground electrode, so that any fluid that occurs, for example condensing on the ground and/or center electrode, can be drained, removed or diverted by means of the bore. The one or more bores are preferably positioned on the ground and/or center electrode in such a way that the fluid can flow off, in particular along the lines of gravity. The bore and/or the plurality of bores can each have a diameter of 0.1 mm to 0.6 mm.

The fluid drainage unit preferably comprises at least one first groove in the ground electrode, with an opening in the first groove being directed in the direction of the center electrode and/or with the fluid drainage unit comprising at least one second groove in the center electrode, with an opening in the second groove being directed in the direction of the ground electrode is.

An advantage of this embodiment can be that the fluid that occurs can be diverted to a specific position with the aid of the first and/or second groove. Furthermore, the groove has turned out to be particularly suitable for allowing occurring fluids, in particular condensates and/or reaction products, to form and for draining them off.

In other words, the fluid discharge unit has at least a first groove in the ground electrode and/or a second groove in the center electrode. Both the first groove and the second groove can be provided parallel to one another in the spark plug unit or in the fluid discharge unit. In this context, the term groove can be understood to mean any form of recess, in particular a slot and/or a notch. For example, the first groove is provided in the ground electrode such that the opening of the first groove protrudes or is directed in the direction of the center electrode. Thus, a condensate dripping from the center electrode onto the ground electrode can be drained off by means of the first groove. Furthermore, the fluid drain unit may include a second groove in the center electrode, wherein the opening of the second groove is oriented toward the ground electrode. Fluid that occurs at the center electrode can thus be diverted via the second groove to the ground electrode or into the combustion chamber. The first groove and/or the second groove can have a groove width of between 0.1 and 0.6 mm and a groove depth of between 0.2 mm and 0.6 mm.

More preferably, the spark plug unit includes a first noble metal plate on the ground electrode, wherein the fluid discharge unit includes a third groove which is arranged at least partially, in particular completely along an outer contour of the first noble metal plate and/or wherein the spark plug unit includes a second noble metal plate on the center electrode, wherein the Fluid discharge unit includes a fourth groove which is at least partially, in particular completely, arranged along an outer contour of the second precious metal plate.

An advantage of this embodiment can be that a fluid that occurs at the center and/or the ground electrode can be drained off in a targeted manner through the third or fourth groove, so that no fluid can form an ignition spark at the first and/or second noble metal plate handicapped.

In other words, the ground electrode has a first noble metal plate (pin), which can be set up in particular to support the formation of an ignition spark or to reduce wear on the ground electrode. Furthermore, a second noble metal plate can be arranged on the center electrode, which is set up to reduce the wear on the center electrode and/or to improve the formation of an ignition spark on the center electrode. Furthermore, the fluid discharge unit can include a third groove, which is arranged in an outer area or along an outer contour of the first precious metal plate. In this case, for example, the first precious metal plate can describe a circular shape, so that the third groove also forms a circular shape around the first precious metal plate. The third groove can be a recess, notch and/or slot. A second noble metal plate is preferably arranged on the center electrode, which can improve the formation of an ignition spark and/or can reduce the wear on the center electrode. The fluid discharge unit has a fourth groove, which is arranged or positioned along the outer contour or along the contour of the second precious metal plate. The fourth groove can be a first recess, notch and/or slot.

The fluid discharge unit preferably has at least one fifth groove, which is arranged on a front end of the center electrode and/or on a front end of the ground electrode.

An advantage of this embodiment can be that the fifth groove supports the dripping off of the fluid that occurs and thus the fluid discharge unit improves the formation of drops of the fluid that occurs by means of the fifth groove.

In other words, the center electrode and/or the ground electrode has at least one front end. In this case, the other end of the center electrode and/or the ground electrode is arranged in particular on an overlapping component, so that the front end of the center electrode and/or the ground electrode protrudes freely into the space. In this case, the fifth groove can be arranged or positioned on the front end of the center electrode and/or the ground electrode in order to improve the formation of drops or the drainage of the fluid that occurs.

More preferably, the first groove and/or the second groove and/or the third groove and/or the fourth groove and/or the fifth groove extend continuously over the center electrode and/or over the ground electrode, in particular over a longitudinal and/or transverse direction.

An advantage of this embodiment can be that the first, the second, the third, the fourth and/or the fifth groove can also drain off the occurring fluid laterally via the center electrode and/or the ground electrode by means of the continuous extent, so that the occurring fluid can be discharged more quickly can be derived from the center electrode or the ground electrode.

In other words, the center electrode and/or the ground electrode has a direction of longitudinal extension, in particular in the direction of its free-floating end. Furthermore, in particular in A transverse direction can be arranged essentially orthogonally to the longitudinal direction. In this context, essentially orthogonal means a deviation of ±20°, in particular ±10°. Furthermore, the orientation of the first groove, the second groove, the third groove and the fourth groove and/or the fifth groove can be aligned in particular parallel and to the longitudinal and/or transverse direction of extent, so that these grooves can also convey the fluid that occurs over the lateral edges of the Ground electrode and / or the center electrode can derive.

The first groove and/or the second groove and/or the third groove and/or the fourth groove and/or the fifth groove are preferably connected to one another in a fluid-conducting manner.

An advantage of this embodiment can be that due to the fluid-conducting connections between the grooves, the shortest possible path can be provided for the fluid that occurs, in order to be able to derive it from the center electrode and/or the ground electrode with the shortest possible path.

The first groove, the second groove, the third groove, the fourth groove and/or the fifth groove can be a recess, a notch and/or a slot which are connected to one another in a fluid-conducting manner. In this context, fluid-conducting means in particular that the occurrence of fluid, which is located, for example, in the first groove, can be conducted into the second groove and vice versa. The grooves can intersect, such as two intersecting notches or slots.

More preferably, a direction of extension of the center electrode is arranged essentially orthogonally to a direction of extension of the ground electrode, with the fluid discharge unit comprising a first elevation and/or a sixth groove on the ground electrode, because the first elevation and/or the sixth groove are at least partially around the direction of extension of the ground electrode.

An advantage of this embodiment can be that a fluid that occurs can also be drained off at a side-mounted ground electrode in order to support the formation of an ignition spark.

In other words, the ground electrode can be a side-mounted ground electrode. The side-mounted ground electrode can include a first elevation and/or a sixth groove. The first elevation and/or the sixth groove can extend at least partially around the direction of extension in the ground electrode. Furthermore, the first elevation and/or the sixth groove can also extend completely around the direction of extension of the ground electrode. The first elevation can have a width of 0.2 to 0.6 mm and a height of 0.2 to 0.6 mm. The sixth groove can have a groove width of 0.1 to 0.6 mm and a groove depth of 0.2 to 0.6 mm.

The spark plug unit preferably has an insulator which is connected to the center electrode, the fluid discharge unit having a second elevation and/or a seventh groove on the insulator, the second elevation and/or the seventh groove being at least partially arranged around an axis of rotation of the insulator , wherein the second bump and/or the seventh groove are arranged on a surface of the insulator which faces the ground electrode.

An advantage of this embodiment can be that the fluid that occurs can be kept away from the center electrode with the aid of the insulator. In addition, the insulator can already have a second elevation and/or seventh groove in a production step before assembly with the spark plug unit, so that assembly of the spark plug unit is further simplified.

In other words, the spark plug unit has an insulator which is arranged in particular around the center electrode. Furthermore, the fluid discharge unit includes a second elevation and/or a seventh groove, which are provided on the insulator. The insulator is of essentially cylindrical design, with the insulator thus being able to form an axis of rotation. The second bump or the seventh groove may extend at least partially around the axis of rotation of the insulator. Furthermore, the second elevation and/or the seventh groove can also extend completely around the axis of rotation of the insulator. Further, the insulator has a surface facing the ground electrode. The second elevation and/or the seventh groove on the insulator can be arranged on this surface.

More preferably, the second elevation and/or the seventh groove is formed concentrically to the axis of rotation of the center electrode and/or the insulator, the second elevation and/or the seventh groove being arranged in an end face region of the insulator.

An advantage of this embodiment can be that the assembly process of the spark plug unit can be further improved with the aid of the concentric design of the insulator, since the insulator can be slipped onto the center electrode more easily.

In particular, the center electrode can be of cylindrical design, so that it forms an axis of rotation. Furthermore, the insulator can also be designed cylindrically, so that it also forms an axis of rotation. The second elevation and/or the seventh groove can be formed or oriented concentrically to these axes of rotation of the center electrode and/or the insulator. Furthermore, the insulator has an end face area, which in particular can face the ground electrode. The second elevation and/or the seventh groove can be arranged on the end face area.

A further aspect of the invention relates to a motor vehicle which has at least one spark plug unit as described above and below. Furthermore, the motor vehicle can have an internal combustion engine, in particular which can be operated using hydrogen.

character list

• 1 eine schematische Darstellung einer Zündkerzeneinheit gemäß einem ersten Ausführungsbeispiel,
• 2 zeigt eine schematische Darstellung einer Zündkerzeneinheit gemäß einem zweiten Ausführungsbeispiel,
• 3 zeigt eine schematische Darstellung einer Masseelektrode gemäß einem dritten Ausführungsbeispiel,
• 4a und 4b zeigen eine Zündkerzeneinheit gemäß einem vierten Ausführungsbeispiel mit einer alternativen Ausgestaltung,
• 5a und 5b zeigen eine Zündkerzeneinheit gemäß einem fünften Ausführungsbeispiel mit einer alternativen Ausgestaltung, und
• 6 zeigt eine schematische Darstellung eines Kraftfahrzeugs.

In the following, preferred embodiments of the invention are described in detail with reference to the accompanying drawings. In the drawings are:

• 1 a schematic representation of a spark plug unit according to a first embodiment,
• 2 shows a schematic representation of a spark plug unit according to a second embodiment,
• 3 shows a schematic representation of a ground electrode according to a third embodiment,
• 4a and 4b show a spark plug unit according to a fourth embodiment with an alternative configuration,
• 5a and 5b show a spark plug unit according to a fifth embodiment with an alternative configuration, and
• 6 shows a schematic representation of a motor vehicle.

Preferred Embodiments of the Invention

In the following, with reference to the 1 until 6 a spark plug unit 1 according to preferred exemplary embodiments of the invention is described in detail.

1 12 represents a spark plug unit 1 . The spark plug unit 1 has a center electrode 2 and a ground electrode 4 . The center electrode 2 and the ground electrode 4 can form an ignition spark in an ignition area 6 . Furthermore, the spark plug unit 1 has a fluid discharge unit 8 . The fluid discharge unit 8 comprises, as in 1 shown, a bore 10 in the ground electrode 4. The fluid discharge unit 8 is set up to discharge a fluid occurring on the center electrode 2 and/or on the ground electrode 4, in particular a condensate and/or a reaction product, from the ignition region 6.

2 FIG. 12 shows a spark plug unit 1 comprising the center electrode 2 and the ground electrode 4. FIG. A first groove 12 is provided on the ground electrode 4 and is designed to drain off any fluid that occurs. Furthermore, the ground electrode 4 has a fifth groove 22 which is arranged on a front end of the ground electrode 4 . The fifth groove 22 comprises a first area 26 which is arranged on a first surface 28 of the ground electrode 4 which faces the center electrode 2 . Furthermore, the fifth groove 22 has a second area 30 which is arranged on a second surface 32 of the ground electrode 4 which faces away from the center electrode 2, the first area 26 and the second area 30 of the fifth groove 22 being connected to one another in a fluid-conducting manner .

3 shows the ground electrode 4, which has the first groove 12. FIG. Furthermore, the ground electrode 4 has a first noble metal plate 16 . In addition, the ground electrode 4 has a third groove 18 . The third groove 18 is arranged along an outer contour 20 of the first precious metal plate 16 .

4a 12 shows the spark plug unit 1, which comprises the center electrode 2 and the ground electrode 4. FIG. The ground electrode 4 is in particular a side-mounted ground electrode. The center electrode 2 has a direction of extension 32 . The direction of extent 34 of the ground electrode 4 is arranged essentially orthogonally to the direction of extent 32 of the center electrode 2 . The center electrode 2 is thus arranged essentially orthogonally to the ground electrode 4 . The fluid drain unit 8 includes a sixth groove 38 which is set up to drain any fluid that occurs from the ground electrode 4 .

In 4b an alternative configuration of the ground electrode 4 positioned on the side is shown. The fluid discharge unit 8 includes a first elevation 36 which is set up to discharge any fluid from the ground electrode 4 . The first elevation 36 extends essentially around the direction of extent 34 of the ground electrode 4.

5a 12 shows the spark plug unit 1, which comprises the center electrode 2 and the ground electrode 4. FIG. Furthermore, the spark plug unit 1 has a insulator 41 on. The insulator 41 is connected to the center electrode 2 . The insulator 41 can be configured cylindrically so that it forms an axis of rotation 44 . A second circumferential elevation 40 can be arranged on the insulator 41 and is designed to drain off any fluid that occurs on the center electrode 2 and/or on the insulator 41 . The second elevation 40 can thus be part of the fluid discharge unit 8 . Furthermore, as in the alternative of 5b shown, the fluid discharge unit 8 has a seventh circumferential groove 42 which is designed to discharge fluid occurring on the center electrode 2 and/or the insulator 41 . Furthermore, the second elevation 40 and/or the seventh groove 42 can be formed concentrically to the axis of rotation 44 of the insulator 41 .

6 shows a motor vehicle 48, which comprises at least one spark plug unit 1, as explained above.

Claims (11)

Spark plug unit (1) for hydrogen ignition in an internal combustion engine, having: - a central electrode (2), and - a ground electrode (4), the center electrode (2) and the ground electrode (4) being arranged to form an ignition spark in an ignition region (6), and the spark plug unit (1) having a fluid compartment unit (8) arranged for this purpose is to discharge a fluid occurring at the center electrode (2) and/or at the ground electrode (4), in particular a condensate and/or a reaction product, from the ignition area (6). spark plug unit claim 1 , wherein the fluid compartment unit (8) comprises at least one bore (10) for draining the fluid in the center electrode (2) and/or in the ground electrode (4). Spark plug unit according to one of the preceding claims, wherein the fluid compartment unit (8) comprises at least one first groove (12) in the ground electrode (4), an opening (14) of the first groove (12) being directed towards the center electrode (2) and /or wherein the fluid division unit (8) comprises at least one second groove in the center electrode (2), an opening of the second groove being directed towards the ground electrode (4). Spark plug unit according to one of the preceding claims, wherein the spark plug unit (1) comprises a first noble metal plate (16) on the ground electrode (4), wherein the fluid compartment unit (8) comprises a third groove (18) which at least partially along an outer contour (20) of the first noble metal plate (16), and/or wherein the spark plug unit (1) comprises a second noble metal plate on the center electrode (2), wherein the fluid compartment unit (8) comprises a fourth groove which runs at least partially along an outer contour (20) of the second noble metal plate is arranged. Spark plug unit according to one of the preceding claims, wherein the fluid compartment unit (8) has at least one fifth groove (22) which is arranged on a front end of the center electrode (2) and/or on a front end of the ground electrode (4). A spark plug assembly as claimed in any preceding claim, wherein the first groove (12) and/or the second groove and/or the third groove (18) and/or the fourth groove and/or the fifth groove (22) is continuous across the center electrode (2) and/or over the ground electrode (4), in particular over a longitudinal and/or transverse stretching direction. Spark plug unit according to one of the preceding claims, wherein the first groove (12) and/or the second groove and/or the third groove (18) and/or the fourth groove and/or the fifth groove (22) are fluidly connected to one another. Spark plug unit according to one of the preceding claims, wherein a direction of extension (32) of the center electrode (2) is arranged essentially orthogonally to a direction of extension (34) of the ground electrode (4), the fluid compartment unit (8) having a first elevation (36) and/or a sixth groove (38) on the ground electrode (4), the first elevation (36) and/or the sixth groove (38) extending at least partially around the direction of extension (34) of the ground electrode (4). Spark plug unit according to one of the preceding claims, wherein the spark plug unit (1) has an insulator (41) which is connected to the center electrode (2), the fluid compartment unit (8) having a second elevation (40) and/or a seventh groove (42 ) on the insulator (41), the second elevation (40) and/or the seventh groove (42) being arranged at least partially around an axis of rotation (44) of the insulator (41), the second elevation (40) and/or the seventh groove (42) are arranged on a surface (45) of the insulator (41) which faces the ground electrode (4). spark plug unit claim 9 , wherein the second elevation (40) and/or the seventh groove (42) is formed concentrically to the axis of rotation (44) of the center electrode (2) and/or the insulator (41), the second elevation (40) and/or which the seventh groove (42) is arranged in an end face area (46) of the insulator (41). Motor vehicle (48) which has at least one spark plug unit (1) according to one of the preceding claims.

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