DE102020126695A1 - Ignition device with a prechamber coupled to an ignition source so that it can rotate without offset, internal combustion engine with an ignition device and motor vehicle with an internal combustion engine - Google Patents

Abstract

The invention relates to an ignition device for an internal combustion engine, having at least one antechamber and having at least one ignition source. The at least one antechamber is coupled to the at least one ignition source so as to be rotatable about a central axis of the ignition device in the direction of longitudinal extension of the ignition device without any offset. Further aspects of the invention relate to an internal combustion engine with at least one ignition device and a motor vehicle with an internal combustion engine.

Description

The invention relates to an ignition device for an internal combustion engine, having at least one antechamber and having at least one ignition source. Further aspects of the invention relate to an internal combustion engine with such an ignition device and a motor vehicle with an internal combustion engine.

Ignition devices are used to provide an ignition source, for example in the form of an ignition spark, in internal combustion engines operated by spark ignition and thus with external ignition, in order to cause ignition of a mixture of fuel and air, also known as a fuel-air mixture. Ignition devices designed as spark plugs are particularly widespread, but other ignition devices, such as so-called laser ignition for igniting the mixture, are also known.

From the AT522050A1 a liquid-cooled internal combustion engine is known, with a cylinder head which has a coolant chamber and with an antechamber which is arranged on the cylinder head and is formed by at least one antechamber component. A fuel supply device connected to the antechamber component opens into the antechamber. The fuel supply device is arranged in a sealing sleeve which is fixedly connected to the prechamber component and which is connected to the prechamber component in a liquid-tight manner at its first end facing the prechamber component.

The object of the present invention is to create an ignition device of the type mentioned at the outset, which can be installed and aligned with little effort, as well as an internal combustion engine with such an ignition device and a motor vehicle with an internal combustion engine.

This object is achieved by an ignition device having the features of patent claim 1, by an internal combustion engine having the features of patent claim 9 and by a motor vehicle having the features of patent claim 10. Advantageous configurations with expedient developments of the invention are specified in the dependent claims.

A first aspect of the invention relates to an ignition device for an internal combustion engine, having at least one antechamber and having at least one ignition source.

According to the invention, it is provided that the at least one antechamber is coupled to the at least one ignition source so as to be rotatable about a central axis of the ignition device in the longitudinal extension direction of the ignition device without any offset. This is advantageous because when the ignition device is installed, on the one hand both the at least one ignition source and the at least one prechamber can be fixed together and thus with little effort, for example on a cylinder head of the internal combustion engine, and on the other hand a relative rotation of the prechamber relative to the ignition source and thus a low-effort alignment of the antechamber relative to the ignition source in the mounted state of the ignition device is possible without this relative rotation leading to the offset between the antechamber and the ignition source in the longitudinal direction of the ignition device.

In the context of the present invention, the expression according to which the prechamber can be rotated around the central axis of the ignition device without offset in the direction of longitudinal extension means that when the prechamber is rotated relative to the ignition device, there is no change in the distance between the prechamber and the ignition device in the direction of longitudinal extension of the ignition device. In other words, the at least one antechamber and the at least one ignition device are coupled to one another so that they can rotate relative to one another without a change in distance. The at least one antechamber and the at least one ignition source can in particular be coupled to one another without a thread.

The invention is based on the finding that in devices known from the prior art, screw connections can be provided between spark plugs and prechamber sleeves, so that when the spark plug rotates relative to the prechamber sleeve or vice versa, it is also possible at the same time, due to a thread pitch of the respective thread of the screw connection There is a length offset between the spark plug and the prechamber sleeve. This makes it difficult to position the prechamber sleeve relative to the spark plug. This is where the invention comes into play, since the design of the present ignition device means that such an offset, as is usual with such screw connections, can also be ruled out during relative rotation.

In an advantageous development of the invention, the at least one antechamber is reversibly detachably coupled to the at least one ignition source. This is advantageous because it allows for a simplified, maintenance-related replacement, for example of the at least one antechamber, without the ignition source being damaged in the process. The term reversibly detachable is therefore to be understood as meaning that the at least one ignition source and the at least one antechamber are non-destructive, in particular without impermissible plastic cal deformation, can be separated from each other.

In a further advantageous development of the invention, the ignition device comprises at least one coupling element, via which the at least one antechamber and the at least one ignition source are rotatably coupled to one another without any offset. This is advantageous since the coupling element can accordingly assume the task of coupling between the antechamber and the ignition source, as a result of which both the at least one antechamber and the at least one ignition source can each have a simple structure.

In a further advantageous development of the invention, the at least one coupling element is designed as a retaining ring. This is advantageous since such a securing ring enables a particularly durable and structurally simple coupling between the at least one ignition source and the at least one antechamber.

In a further advantageous development of the invention, the at least one coupling element is connected in one piece to the at least one antechamber or in one piece to the at least one ignition source. This is advantageous because the ignition device has a particularly small number of individual parts overall and can accordingly be assembled particularly easily. The coupling element can be designed, for example, as a partial area of the antechamber. As an alternative to this, the coupling element can also be designed as a partial area of the ignition source.

In a further advantageous development of the invention, the at least one coupling element is designed as a projection. Such a projection can be produced particularly easily, for example by rolling processing, in particular rolling, of the at least one antechamber or the ignition source on the antechamber or on the ignition source. The projection can preferably be configured in an annular manner, in particular in an annular manner around a central axis of the ignition device oriented in the direction of longitudinal extension.

The central axis of the ignition device can generally also correspond to the central axis of the at least one antechamber and/or the at least one ignition source.

In a further advantageous development of the invention, the at least one ignition source is designed as a spark plug. This is advantageous because it enables a particularly reliable ignition, ie a reliably reproducible ignition of a fuel-air mixture, to take place by means of the ignition source.

The at least one antechamber can preferably be designed at least in regions as a counter-electrode for the at least one ignition source designed as a spark plug.

In a further advantageous development of the invention, the at least one ignition source and the at least one antechamber form a sealing seat with one another. This is advantageous because it enables reliable sealing between the antechamber and the ignition source even without further sealing elements, for example sealing rings. The sealing seat can be gas-tight, ie prevent gas from escaping from the antechamber in the area of the ignition source. The antechamber and/or the ignition source can preferably have a conical contact area on the sealing seat, on which the antechamber and the ignition source bear against one another, forming the sealing seat. A particularly reliable seal can be created by the conical contact area.

A second aspect of the invention relates to an internal combustion engine with at least one ignition device according to the first aspect of the invention. This is advantageous because with such an internal combustion engine, assembly and adjustment of the ignition device are made possible with little effort.

A third aspect of the invention relates to a motor vehicle with an internal combustion engine according to the second aspect of the invention, with the latter enabling particularly easy assembly and easy adjustment of the ignition device.

The preferred embodiments presented in relation to one of the aspects and their advantages apply correspondingly to the respective other aspects of the invention and vice versa.

The features and combinations of features mentioned above in the description and the features and combinations of features mentioned below in the description of the figures and/or shown alone in the figures can be used not only in the combination specified in each case, but also in other combinations or on their own, without going beyond the scope of the leave invention.

Further advantages, features and details of the invention result from the claims, the following description of preferred embodiments and with reference to the drawings.

• 1 eine schematische Seitenansicht einer Zündvorrichtung;
• 2 eine schematische Schnittdarstellung der Zündvorrichtung gemäß einer Schnittlinie A-A in 1; und
• 3 ein stark abstrahiert dargestelltes Kraftfahrzeug und eine schematische Schnittdarstellung eines Teilbereichs einer Verbrennungskraftmaschine, welche einen Zylinderkopf aufweist, an welchem die Zündvorrichtung derart montiert ist, dass eine Vorkammer in einen Brennraum der Verbrennungskraftmaschine ragt.

The invention is explained again below using a specific exemplary embodiment. For this shows:

• 1 a schematic side view of an ignition device;
• 2 a schematic sectional view of the ignition device along a section line AA in 1 ; and
• 3 a highly abstract motor vehicle and a schematic sectional view of a portion of an internal combustion engine having a cylinder head on which the ignition device is mounted in such a way that an antechamber protrudes into a combustion chamber of the internal combustion engine.

1 shows a schematic side view of an ignition device 10 for an internal combustion engine 100. The ignition device 10 can on one, in 3 Sectionally shown cylinder head 102 of the internal combustion engine 100 is arranged and thereby reversibly releasably fixed. The internal combustion engine 100 is used to drive a motor vehicle K, which 3 is shown in a highly abstracted manner. In other words, motor vehicle K includes internal combustion engine 100 and thus also ignition device 10.

Ignition device 10 includes a prechamber 20 and an ignition source 30. Ignition source 30 is designed as a spark plug and includes a center electrode 36 and, in the present case, also a counter-electrode 38, also referred to as a ground electrode, as shown in a schematic sectional view of ignition device 10 in FIG 2 according to a 1 illustrated section line AA can be seen.

The antechamber 20 also includes an antechamber wall 22 on which passage openings 24 are arranged at an end of the antechamber 20 facing away from the ignition source 30 . The through openings 24 connect in one, in 3 shown installation position of ignition device 10 on cylinder head 102, a prechamber interior 26, delimited at least in regions by prechamber wall 22, with a combustion chamber 104 of internal combustion engine 100. During operation of internal combustion engine 100, a fluid or a fluid mixture, for example in the form of a fuel-air mixture , from combustion chamber 104 via through-openings 24 into prechamber interior 26 and are ignited there using ignition source 30 designed as a spark plug, especially since center electrode 36 and counter-electrode 38 are arranged in prechamber interior 26 .

The antechamber 20 is coupled to the ignition source 30 in the longitudinal direction L of the ignition device 10 so as to be rotatable about a central axis M of the ignition device 10 without any offset. In the present case, the direction of longitudinal extent L is only in 2 shown and illustrated by a double arrow, which is also only in 2 aligned with the central axis M of the ignition device 10 indicated by a dot-dash line. In other words, the direction of longitudinal extension L and the central axis M run coaxially to one another. The central axis M of the ignition device 10 also corresponds to the central axis of the antechamber 20 and the ignition source 30.

Based on 2 and 3 It can be seen that the ignition device 10 comprises a coupling element 40, which is designed here as a retaining ring and via which the antechamber 20 and the ignition source 30 are reversibly detachable and rotatably coupled to one another in the longitudinal direction L without any offset.

As an alternative to this, the coupling element 40 can also be connected in one piece to the antechamber 20 or in one piece to the ignition source 30 and can be designed, for example, as a projection, which is not shown in detail in the present case. The projection can be produced by forming the ignition source 30 or the antechamber 20, for example by rolling.

The coupling element 40 is accommodated on the one hand in a receiving groove 33 which is arranged on an ignition source wall 32 of the ignition source 30 . On the other hand, the coupling element 40 is supported on a shoulder 23 of the antechamber 20 formed on the antechamber wall 22 . By receiving the coupling element 40 (here: retaining ring) in the receiving groove 33 and by supporting the coupling element 40 on the shoulder 23, an axial relative movement, i.e. a relative movement in the axial direction, namely along the central axis M and thus in the longitudinal direction L between of the antechamber 20 and the ignition source 30 is prevented, so the relative rotation about the center axis M between the antechamber 20 and the ignition source 30 without offset in relation to the direction of longitudinal extent L is possible. In other words, the pre-chamber 20 and the ignition source 30 can be rotated relative to one another due to their coupling via the coupling element 40, without there being an offset in the longitudinal direction L between the pre-chamber, in contrast to a conventional screw connection of the ignition source 30 to the pre-chamber 20 20 and the ignition source 30 comes.

Based on 2 can also be seen that the ignition source wall 32 has a thread includes area 34, on which an external thread is arranged. The threaded area 34 and thus the external thread serve to fix the ignition device 10 to the cylinder head 102 in a reversibly detachable manner.

Threaded area 34 has a larger diameter (measured perpendicularly to central axis M) than areas of ignition source 30 that differ from threaded area 34.

The coupling element 40 can be arranged in a particularly space-saving manner in the direction of longitudinal extension L at the height of the threaded area 34, as illustrated in FIG 2 or 3 is recognizable. Here, the large diameter of the threaded area 34 can be used to couple the antechamber 20 via the coupling element 40 to the ignition source 30 radially inside the threaded area 34, in other words between the threaded area 34 and the central axis M.

The ignition source 30 and the prechamber can also form a sealing seat 12 with one another in order to seal off the prechamber interior 26 at least in regions. Sealing seat 12 can be embodied as gas-tight and, even during fired operation of internal combustion engine 100, prevent any gases at high pressure in combustion chamber 104, in particular exhaust gases, from escaping from prechamber interior 26 and away from combustion chamber 104 in the direction of longitudinal extent L.

The present ignition device 10 allows the pre-chamber 20 to be rotated relative to the ignition source 30 without--just like when the pre-chamber 20 is simply plugged onto the ignition source 30--thereby resulting in a change in the distance between the pre-chamber 20 and the ignition source 30 in the longitudinal direction L comes. An advantage of the present ignition device 10 compared to simply plugging it on is that the coupling element 40 also provides a safeguard against loss, through which an undesired detachment of the prechamber 20 from the ignition source 30, i.e. for example an undesired sliding of the prechamber 20 from the ignition source 30 in Longitudinal direction L can be prevented.

In the internal combustion engine 100, the antechamber 20 of the ignition device 10 is not connected to the cylinder head 102 via a press fit or conical seat, but is fixed reversibly detachably to the cylinder head via the threaded area 34 together with the ignition source 30 . In contrast to the connection via the press fit or conical seat, the ignition device 10 can be dismantled from the prechamber 20 without destroying it and, in particular, without damaging it. The dismantling of the ignition device 10 with its antechamber 20 can be particularly useful if increased wear, for example of the antechamber 20, is to be expected, if the antechamber 20 or the ignition source 30 is not durable over the entire life cycle of the internal combustion engine 100. This can be the case, for example, if the counter-electrode 38 assigned to the ignition source 30 in the present example is not the same as in 1 until 3 shown as part of the ignition source 30, but instead is designed as part of the antechamber 20, i.e., for example, it is integrated into the antechamber 20 and/or the antechamber 20 assumes the function of the counter electrode 38 (ground electrode), which is not shown here.

To assemble the ignition device 10, it can be divided into an in 3 shown receiving opening 106 on the cylinder head 102 and screwed to the threaded portion 34 with an arranged at the receiving opening 106 internal thread 108 of the cylinder head 102 . As a result, the antechamber 20 is pressed in the direction of the combustion chamber 104 on the cylinder head 102 . At least in time before prechamber 20 is pressed with cylinder head 102, i.e., for example, between the start of screwing threaded region 34 to internal thread 108 and the end of this screwing, prechamber 20 and ignition source 30 can, due to their coupling via coupling element 40, be relatively to each other and rotated about the central axis M, whereby a directional shoring of the antechamber 20 is made possible. As a result, for example, the passage openings 24 can be aligned relative to an injector of the internal combustion engine 100, which is not shown in detail here and which can be designed for injecting fuel directly into the combustion chamber 104. If the ignition device 10 is dismantled, i.e. when the ignition device 10 is detached from the cylinder head 102, the coupling of the coupling element 40 (here: retaining ring) with the receiving groove 33 on the ignition source 30 and with the shoulder 23 designed as a collar on the antechamber 20 ensures that that the antechamber 20 can be detached from the cylinder head 102 together with the ignition source 30 when the ignition device 10 is unscrewed, that is to say when the screwed connection of the threaded region 34 with the internal thread 108 is separated.

Reference List

10

ignition device

12

tight fit

20

antechamber

22

antechamber wall

23

Unit volume

24

passage openings

26

antechamber interior

30

ignition source

32

ignition source wall

33

receiving groove

34

thread area

36

center electrode

38

counter electrode

40

coupling element

100

internal combustion engine

102

cylinder head

104

combustion chamber

106

intake opening

108

inner thread

109

tight fit

K

motor vehicle

L

longitudinal direction

M

central axis

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• AT 522050 A1 [0003]

Claims (10)

Ignition device (10) for an internal combustion engine (100), with at least one antechamber (20) and with at least one ignition source (30), characterized in that the at least one antechamber (20) in the longitudinal direction (L) of the ignition device (10) without an offset a central axis (M) of the ignition device (10) is rotatably coupled to the at least one ignition source (30). Ignition device (10) after claim 1 , characterized in that the at least one antechamber (20) is reversibly detachably coupled to the at least one ignition source (30). Ignition device (10) after claim 1 or 2 , characterized in that the ignition device (10) comprises at least one coupling element (40) via which the at least one antechamber (20) and the at least one ignition source (30) are rotatably coupled to one another without offset. Ignition device (10) after claim 3 , characterized in that the at least one coupling element (40) is designed as a locking ring. Ignition device (10) after claim 3 , characterized in that the at least one coupling element (40) is connected in one piece to the at least one antechamber (20) or in one piece to the at least one ignition source (30). Ignition device (10) after claim 5 , characterized in that the at least one coupling element (40) is designed as a projection. Ignition device (10) according to one of the preceding claims, characterized in that the at least one ignition source (30) is designed as a spark plug. Ignition device (10) according to one of the preceding claims, characterized in that the at least one ignition source (30) and the at least one antechamber form a sealing seat (12) with one another. Internal combustion engine (100) with at least one ignition device (10) according to one of Claims 1 until 8th . Motor vehicle (K) with an internal combustion engine (100). claim 9 .

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