DE102017214820A1 - Injector with improved injection - Google Patents

Abstract

The present invention relates to an injector for introducing a fluid, comprising: a spray hole assembly (3) having a plurality of first spray holes (30a, 30b, 30c) and a plurality of second spray holes (30d, 30e, 30f), and a closure member (4 ) for releasing and closing the spray holes, the plurality of first spray holes (30a, 30b, 30c) being arranged on a first pitch circle (31), and wherein the plurality of second spray holes (30d, 30e, 30f) are arranged on a second pitch circle (30). 32) are arranged.

Description

State of the art

The present invention relates to an injector for introducing a fluid, in particular a fuel injector, with a significantly improved spray pattern.

Injectors are e.g. in the form of fuel injectors in different configurations. Here, depending on the application, one or more injection holes are provided which, for example, inject fuel directly into a combustion chamber during an opening process of the injector. Usually, the injection holes have a circular shape. It is also known that the jets emerging from the spray holes can meet, with the jets usually meet in the vicinity of the spray holes at a certain angle. However, these so-called collision beams reduce flexibility in the design of the injectors. Due to the collision requirement, the injection holes are usually also arranged at a different angle to a central axis of the injector, which can lead to incomplete fillings of the injection holes when the injector is open, also depending on the pressure level.

Disclosure of the invention

The injector according to the invention for introducing a fluid with the features of claim 1 has the advantage that a much greater flexibility in terms of an arrangement of a plurality of spray holes is possible. As a result, a simplified adaptation of spray patterns to the respective requirements of various engine manufacturers can be achieved. This is inventively achieved in that the injector has a spray pattern with a plurality of first spray holes and a plurality of second spray holes. Furthermore, the injector comprises a closing element for releasing and closing the injection holes. The plurality of first spray holes is arranged on a first pitch circle and the plurality of second spray holes is arranged on a second pitch circle. The inventive arrangement of the injection holes on a first pitch circle and a second pitch circle allows a flexible design of the fluid jets emerging from the spray holes. Furthermore, a strength-optimized design of the component, in which the injection holes are arranged, can be achieved.

The dependent claims show preferred developments of the invention.

Preferably, all centers of the plurality of first injection holes are arranged on the first pitch circle and all midpoints of the plurality of second injection holes are arranged on the second pitch circle. In this way, a particularly simple production of the spray hole arrangement can be achieved.

Particularly preferably, the first and second pitch circle are concentric with each other.

More preferably, the two concentrically arranged partial circuits are also arranged concentrically to a central axis of the injector. In this way, in particular a uniform filling of the plurality of spray holes can be achieved.

According to a further preferred embodiment of the invention, the number of first and second spray holes are the same. In this way, in particular, a spray hole arrangement can be realized in a simple manner, in each case a spray hole of the first pitch circle and the second pitch circle are arranged so that meet the fluid jets of these two injection holes after exiting the spray holes.

A further preferred embodiment of the invention provides that a first center of a first injection hole and a second center of a second injection hole lie on a straight line through a partial circle center of one of the partial circles, which form a spray hole pair.

More preferably, at least two spray holes are arranged to produce fluid jets which meet after a spray hole outlet. As a result, collision beams can be realized in a simple manner, for example in a combustion chamber. More preferably, this results in a plane perpendicular to a central axis of the injector, an oval-shaped spray pattern.

According to a further preferred embodiment of the invention, the first injection holes and / or the second injection holes are formed with an elliptical cross-section. By using the elliptical cross section results in a larger filling of the injection holes, whereby an injection quantity per unit time can be increased.

More preferably, the first and / or second injection holes each have at least one precursor.

Preferably, a collision point of the fluid jets is at least at a distance from an exit from the injection hole, which is greater than half the diameter of the injection hole. For elliptical spray holes, the distance is greater than half of the small ellipse diameter.

The injector according to the invention is particularly preferably a fuel injector. The fuel injector may in this case be a direct injection injector, which injects fuel directly into a combustion chamber, or a fuel injector, which injects fuel into a suction pipe or the like. Alternatively, the injector is designed for the injection of urea or water.

Furthermore, the invention relates to an internal combustion engine with an injector according to the invention.

list of figures

• 1 eine schematische Schnittansicht eines Injektors gemäß einem ersten Ausführungsbeispiel der Erfindung,
• 2 eine schematische Ansicht einer einspritzseitigen Seite des Injektors von 1 mit einem entsprechenden Spritzbild,
• 3 eine schematische Ansicht einer einspritzseitigen Seite eines Injektors gemäß einem zweiten Ausführungsbeispiel mit einem entsprechenden Spritzbild,
• 4 eine schematische Ansicht einer einspritzseitigen Seite eines Injektors gemäß einem dritten Ausführungsbeispiel mit einem entsprechenden Spritzbild, und
• 5 eine schematische Ansicht einer einspritzseitigen Seite eines Injektors gemäß einem vierten Ausführungsbeispiel mit einem entsprechenden Spritzbild.

Hereinafter, preferred embodiments of the invention will be described with reference to the accompanying drawings. In the drawing is:

• 1 a schematic sectional view of an injector according to a first embodiment of the invention,
• 2 a schematic view of an injection-side side of the injector of 1 with a corresponding spray pattern,
• 3 FIG. 2 a schematic view of an injection-side side of an injector according to a second exemplary embodiment with a corresponding spray pattern, FIG.
• 4 a schematic view of an injection side of an injector according to a third embodiment with a corresponding spray pattern, and
• 5 a schematic view of an injection-side side of an injector according to a fourth embodiment with a corresponding spray pattern.

Preferred embodiments of the invention

Below we refer to the 1 and 2 an injector 1 according to a first embodiment of the invention described in detail.

How out 1 can be seen, includes the injector 1 a housing 2 and a closing element 4 with a ball 41 , which at a sealing seat 5 seals. An actuator for moving the closing element 4 is a magnetic actuator in this embodiment 6 with an anchor 60 and a coil 61 , The reference number 14 denotes a return element.

The in 1 shown injector is an inwardly opening injector, wherein the 1 shows the closed state of the injector. This seals the ball 41 at the seal seat 5 from.

In this embodiment, the sealing seat 5 on a separate component 7 arranged, wherein in this component 7 also a spray hole arrangement 3 is arranged.

The injection hole arrangement 3 is in particular out 2 seen. How out 2 can be seen, includes the spray hole arrangement 3 a total of six spray holes 30a . 30b . 30c . 30d . 30e and 30f , Here are the injection holes 30a . 30b . 30c on a first circle 31 the injection hole arrangement arranged and form a plurality of first spray holes.

The three spray holes 30d . 30e and 30f are on a second circle 32 arranged and form a plurality of second spray holes.

How farther 2 is apparent, are the first circle 31 and the second circle 32 arranged concentrically with each other. Furthermore, the two subcircles 31 . 32 also concentric to a central axis X - X of the injector 1 arranged.

M denotes a center of the first and second pitch circle 31 . 32 ,

How farther 2 it can be seen form the first injection hole 30a and the second spray hole 30d a spray hole pair and are with their centers on a common straight line G arranged, which also through the central axis X - X of the injector 1 and the centers M leads. In the same way, the respectively associated first and second injection holes are on further straight lines G2 and G3 through the central axis X - X arranged. The straight lines are each positioned at an angle of 120 ° adjacent to each other. The diameters of the injection holes are the same size.

The respective injection hole pairs 30a and 30d . 30b and 30e such as 30c and 30f forming first and second injection holes are arranged such that in each case a collision of the running through them fluid jets (in 1 schematically for two fluid jets 3a . 3d drawn) takes place. The corresponding spray pattern is here in the right part of 2 shown. This results in three ellipses E1 . E2 and E3 , where the right representation in 2 in a plane E perpendicular to the central axis X - X of the injector, as in 1 shown is shown.

As a result, by the positioning of the first and second injection holes on a first and second pitch circle an undesirably strong beam propagation in a combustion chamber 12 prevent and thus a component wetting of components, which the combustion chamber 12 limit, be avoided. Thus, in particular a reduction of fuel use of cylinder walls on the combustion chamber 12 be achieved.

The arrangement of the first and second injection holes on the first and second pitch circle 31 . 32 allows not only a simple production but also a strength-optimized design of the component 7 , in which the injection holes are formed. Penetration can be achieved by selecting a collision angle and a distance of a collision location at which the fluid jets 3a and 3d collide (s. 1 ), after leaving the spray holes.

3 shows a spray hole arrangement 3 an injector according to a second embodiment of the invention. The second embodiment substantially corresponds to the first embodiment, wherein, as in 3 shown a cross section of the first and second injection holes 30a . 30b . 30c . 30d . 30e and 30f is elliptical. Here are the centers of the ellipses on the first circle 31 and the second circle 32 , This also makes a jet image in the plane E, comprising three ellipses E1 . E2 and E3 be enabled. Due to the elliptical design of the injection holes, however, a hole filling level improves. As a result, a precision in the impact of the fluid jets against each other in the common collision location can be increased. Thus, a larger amount of fluid can flow through the elliptical injection holes, so that opening times of the injector can be reduced. Also, by using elliptical cross-sections for the injection holes, manufacturing tolerance can be reduced.

4 shows a spray hole arrangement 3 according to a third embodiment of the invention. In contrast to the first and second embodiments, in the third embodiment, a number of the plurality of first and second spray holes on the first pitch circle 31 and the second circle 32 differently. How out 4 is apparent, are on the first pitch circle 31 only two first injection holes 30a . 30b arranged. On the second circle 32 are four second spray holes 30d . 30e . 30f and 30g intended. A corresponding spray pattern is in the right part of 4 shown, again three ellipses E1 . E2 and E3 in the plane e form, however, have a different orientation than in the previous embodiments.

The two subcircles 31 . 32 are again concentric with each other and concentric with the central axis X - X of the injector.

5 shows a spray hole arrangement 3 according to a fourth embodiment of the invention. In contrast to the preceding embodiments, in the fourth embodiment, only two spray-hole pairs, each having a first injection hole on the first pitch circle 31 and a second injection hole on the second pitch circle 32 have provided. On the second circle 32 is also a single spray hole 30g intended. The single spray hole 30g has a circular cross-section, resulting in the spray pattern in the plane E, a circular beam cross-section K1 results. Furthermore, the first circle 31 and the second circle 32 no longer concentric with each other. How out 5 is apparent, is a midpoint M1 of the first circle 31 offset to the central axis X - X of the injector. Here is the second circle 32 concentric to the central axis X - X arranged. This results in a different spray pattern in the plane e as in the right part of 5 shown.

For all described embodiments, it should be noted that in each case precursors can be provided on the spray holes on the first pitch circle and / or on the second pitch circle. Furthermore, the embodiments in which a circular cross section of the injection holes has been described, may be formed with an elliptical cross section.

In the exemplary embodiments, it has also been described that in each case two spray holes form a pair of beams, which generates fluid jets which meet after emerging from the spray holes. However, it is also possible that a third injection hole and / or further injection holes are provided, the fluid jets meet with the fluid jets of the spray hole pair.

Also, the diameters of the spray holes shown in a circle can each vary.

Another combination option is given if, in addition to a first and a second pitch circle, a third pitch circle or a fourth pitch circle or a plurality of pitch circles is additionally provided. Also, any combination of spray holes of circular cross section and elliptical cross section is possible.

The injector according to the invention is preferably designed as a fuel injector, but may also be designed as a urea injector or as a water injector.

Claims (11)

Injector for introducing a fluid, comprising: - a spray-hole arrangement (3) having a plurality of first spray holes (30a, 30b, 30c) and a plurality of second spray holes (30d, 30e, 30f), and - a closure member (4) for release and closing the spray holes, wherein the plurality of first spray holes (30a, 30b, 30c) are disposed on a first pitch circle (31), and wherein the plurality of second spray holes (30d, 30e, 30f) are disposed on a second pitch circle (32). Injector after Claim 1 , Wherein all centers of all the first spray holes (30a, 30b, 30c) lie on the first pitch circle (31) and / or with all centers of the second spray holes (30d, 30e, 30f) on the second pitch circle (32). Injector according to one of the preceding claims, wherein the first pitch circle (31) is arranged concentrically to the second pitch circle (32). Injector after Claim 3 wherein the first pitch circle (31) and the second pitch circle (32) are arranged concentrically to a central axis (XX) of the injector. An injector according to any one of the preceding claims, wherein a number of the first (30a, 30b, 30c) and second injection holes (30d, 30e, 30f) on the first and second pitch circles (31, 32) are the same. Injector after Claim 5 in which center points of a spray hole pair formed by a first spray hole and a second spray hole each lie on a straight line (G1, G2, G3) through a center (M) of at least one of the pitch circles (31, 32). Injector according to one of the preceding claims, wherein at least two injection holes, in particular a first and a second injection hole, are adapted to generate fluid jets which meet after an exit from the injection hole. Injector after Claim 7 , wherein the fluid jets form an oval-shaped spray pattern (E1, E2, E3) in a plane (E) perpendicular to the central axis (XX) of the injector. Injector according to one of the preceding claims, wherein the first injection holes (30a, 30b, 30c) and / or the second injection holes (30d, 30e, 30f) have an elliptical cross-section. Injector according to one of the preceding claims, wherein the first injection holes (30a, 30b, 30c) and / or the second injection holes (30d, 30e, 30f) each have a precursor. An injector according to any one of the preceding claims, wherein the first injection holes (30a, 30b, 30c) and the second injection holes (30d, 30e, 30f) respectively form injection hole pairs (30a and 30d, 30b and 30e, 30c and 30f) thus arranged in that a collision of the fluid jets passing through them takes place in each case.

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