EP1399668B1 - Fuel injection valve for internal combustion engines - Google Patents

Abstract

The invention relates to a fuel injection valve for internal combustion engines, comprising an injection nozzle which is fixed to a nozzle holder or an injector. Said injection nozzle is provided with a body (1, 17, 24) and a needle (3). Said nozzle needle (3) can be axially displaced in a bore hole (2) in the nozzle body (1, 17, 24). Said nozzle body (1, 17, 24) has at least one identifying mark or at least one key surface for aligning the nozzle body (1, 17, 24) with the nozzle holder or injector. The invention also relates to a method for aligning the nozzle body (1, 17, 24) with the nozzle holder or injector, during the assembly of an inventive fuel injection valve.

Description

Technical area

Fuel injectors or injectors are important components of internal combustion engines. Fuel injectors are needed for metered injection, conditioning of fuel, shaping of injection history and sealing against the combustion chamber. A fuel injector includes an injector which is inserted into a holder body, e.g. a nozzle holder, is integrated. However, the injection nozzles can also, for example in the accumulator injection system "common rail", be installed in injectors which take over the function of the nozzle holders. With electrically controllable injectors, start of injection and injection quantity are set.

State of the art

Nozzle holder combinations and injectors, especially for hole nozzles, have a large variety of variants.

From DE 195 08 636 A1, for example, a nozzle with nozzle holder is known. The injection nozzle is attached centrally to the nozzle holder with a nozzle retaining nut. When the nozzle holder is screwed together with the nozzle retaining nut, an intermediate disk is pressed against the sealing surfaces of the nozzle holder and of the body of the injection nozzle. The intermediate disc forms the stroke stop of the nozzle needle of the injection nozzle and also serves to align the injection nozzle relative to the body of the nozzle holder by means of fixing pins. The fuel passes through an inlet bore in the body of the nozzle holder and a bore in the washer to an inlet bore of the nozzle body and then into the seating area of the injector.

An illustration of another nozzle holder combination is known from Diesel Engine Management, Robert Bosch GmbH, second edition (1998), Vieweg, Wiesbaden, page 91. A Blind hole nozzle, which can be installed in a common rail injector, is shown in the same book p 279.

On the basis of a plurality of cylindrical fixing pins or other formable mold elements, a tangential alignment of a nozzle body is made to a holding body to arrange the spray jets of injected into the combustion chamber fuel in a different depending on the type of internal combustion engine angle to the glow plug and thus to improve the injection conditions. The fixing pins in the intermediate disc, which serve to align the injection nozzle relative to the nozzle holder or injector, have the disadvantage that in the nozzle body blind holes are required to accommodate the fixing pins and that these blind holes reduce the fatigue strength of the nozzle body. This reduces the maximum load on a fuel injector due to vibration induced fatigue.

EP 0 672 826 B1 relates to a fuel injector for supplying fuel to a diesel engine having a stepped cylindrical nozzle body in which a fuel pressure operated valve member is disposed and having a cylindrical nozzle holder to which the nozzle body is fixed, the nozzle holder having a fuel inlet passage; which communicates with a fuel inlet and a fuel delivery passage in the nozzle body. Further, the fuel injector includes a shoulder engaging collar, wherein the step is defined between a further and a narrower portion of the nozzle body and a clamp for securing the collar to the nozzle holder for holding the nozzle body relative to the nozzle holder, wherein the nozzle body with a recess which extends from the step to the nozzle holder. Furthermore, the nozzle holder is provided with a complementary recess adjacent to the recess in the nozzle body, wherein the clamp is arranged in the recesses.

EP 0 921 304 B1 relates to a nozzle with a nozzle holder and a nozzle tip, wherein the nozzle tip is provided with at least one outlet opening. Further, at the top is a structure which provides an indication of the angular positions of the apertures. The tip includes an area that is a frictional connection in the nozzle holder to form a substantially liquid-tight seal between the nozzle holder and the tip. The nozzle holder and the Tip are engaged by a screw thread with each other and are attached to each other. A method of manufacturing such a nozzle includes the step of aligning the structure with a portion of the nozzle holder.

Presentation of the invention

An advantage of the present invention is that the fatigue strength of the nozzle body of a fuel injection valve increases, thereby eliminating the fixing pins and associated blind holes. The elimination of the fixing pins further results in a reduction of costs and time required in the production of the nozzle holder combination. Further, the present invention increases the accuracy of the fixation of the injection nozzle to the nozzle holder. The same advantages are achieved for injectors installed in injectors.

These advantages are achieved by an inventive fuel injection valve for internal combustion engines with a clamped to a nozzle holder or an injector injector comprising a nozzle body and a nozzle needle. In this case, the nozzle needle is axially displaceable in a bore in the nozzle body. The nozzle body contains at least one marking and may optionally contain a key surface for alignment of the nozzle body relative to the holding body or an injector body. A marking or recess which is machine-readable (identification of the position of the marking eg via camera system in production / assembly line) can be arranged both in the upper area of the nozzle body and in its shaft area extending to the combustion chamber. An alignment of the nozzle body to the holding body can be carried out by means of an assembly or clamping tool. An attached to the nozzle body key surface can be fitted into an assembly tool, whereby the nozzle body is aligned in the correct position relative to the holding body. The marking provided on the nozzle body can also be achieved by means of an optical system through a viewing window Detect in a clamping tool. The inventive solution for fixing and alignment of the holding body and nozzle body serving each other fixing pins can be omitted, so that the operations for the production of Fixiergeometrie ie bore the blind holes in the nozzle body and milling grooves or the like in the nozzle body and holding body can also be omitted. As a result, further metrological effort can be saved. In addition, processing steps, such. B. as the deburring sharp-edged Fixiemuten that arise during milling, now accounts.

With the proposed solution, a torque applied to produce a sealing force acting in the axial direction becomes superfluous. The nozzle retaining nut with which holding body and nozzle body are connected to each other, is only "applied" after application of the axial biasing force by clamping or mounting tool. It can also errors in the assembly, such. As a shearing of the pins by an excessive friction torque or failure to reach the required target torque at angle-controlled installation, exclude. By avoiding fixing pins between the holding body and the nozzle body further errors with regard to the position and dimensional stability of the Fixiergeometrie can be avoided in the future. In the case of rotationally symmetrical nozzle bodies, any alignment in the case of measuring test procedures can be dispensed with in future. With the solution proposed by the invention, a much more accurate position of the nozzle body to the injector or the holding body can be achieved, that the nozzle body is aligned with the holding body and the alignment by image processing z. B. can be monitored via an optical system. This is difficult to achieve in today's assembly process due to the existing tolerance chains. With the solution according to the invention, substantially smaller side angle tolerances are also possible, which is favorable with regard to the prevailing development tendency, to increase the number of spray holes for introducing the fuel into the combustion chamber of a self-cynical internal combustion engine. Due to the lack of fixing pins and the strength of the nozzle body weakening blind holes can be achieved a much higher compressive strength. Also favorable is a constant surface pressure on the bearing surfaces, ie the sealing surface of the nozzle body and the opposite end face of the holding body. A constant surface pressure becomes a significant qualitative consumption of the sealing surfaces. Due to the initiation of the biasing force by means of clamping or assembly tool, the nozzle retaining nut, which adjusts the nozzle body against the holding body and maintains the sealing force, be relieved of mechanical stress, since it does not transmit torque in the bias of holding bodies and nozzle bodies against each other. This in turn has the consequence that with the proposed solution according to the invention an increase in the axial sealing force is possible and an enlargement of the nozzle body collar can be achieved. Furthermore the nozzle body is subject to no torsional stress; Furthermore, can be avoided by the proposed solution according to the invention sealing surface damage due to unwanted twisting.

The above advantages will be apparent to all types of nozzles, e.g. for seat hole or blind hole nozzles, in particular for the nozzle of a piezo injector.

drawing

Reference to the drawings, the invention will be explained in more detail below.

Figur 1

einen Schnitt durch eine Einspritzdüse gemäß dem Stand der Technik mit Sacklöchern für die Fixierstifte;

Figur 2a, b

eine schematische Darstellung von erfindungsgemäßen Düsenkörpern mit möglichen Formen der Markierung und

Figur 3

eine schematische Darstellung eines erfindungsgemäßen Düsenkörpers mit Schlüsselfläche und einem dazugehörigen Montagewerkzeug,

Figur 4

die Darstellung einer Düsenkörper-/Haltekörperverbindung mit vergrößerter Düsenspannmutterbohrung und

Figur 5

einer Haltekörper-/Düsenkörperverbindung mit reduziertem Schaftdurchmesser am Düsenkörper.

It shows:

FIG. 1

a section through a injector according to the prior art with blind holes for the fixing pins;

FIG. 2a, b

a schematic representation of nozzle bodies according to the invention with possible forms of marking and

FIG. 3

a schematic representation of a nozzle body according to the invention with a key surface and an associated assembly tool,

FIG. 4

the representation of a nozzle body / holding body connection with enlarged nozzle spanner bore and

FIG. 5

a Haltekörper- / nozzle body connection with reduced shaft diameter on the nozzle body.

variants

Figure 1 shows a section through an injection nozzle according to the prior art. The injection nozzle comprises a nozzle body 1 and a bore 2, in which the nozzle needle 3 is axially guided. The nozzle needle 3 carries at its lower end a sealing cone 4, which is pressed when the injection nozzle is closed on the likewise conical sealing surface 5 of the nozzle body. In the conical tip of the nozzle body are injection holes 6, which are supplied via an inlet bore 7 and a pressure chamber 8 with the injector open with fuel. The upper sealing surface 9 of the injection nozzle is connected to a (not shown) nozzle holder or injector. The injector is with it a nozzle retaining nut (also not shown) attached to the nozzle holder or injector. When screwing together the nozzle holder or injector and nozzle retaining nut, a washer is generally pressed against the sealing surfaces 9 of nozzle holder or injector and nozzle body 1. The alignment and fixation of the nozzle body 1 relative to the nozzle holder or injector takes place in the prior art by means of fixing pins stuck in blind holes in the intermediate disc on one side and in blind holes in the nozzle holder or injector and the nozzle body 1 on the other side. FIG. 1 shows such a pin hole 10 in the nozzle body 1. However, the pin hole 10 reduces the vibration resistance of the nozzle body 1. In the present invention, the pin holes 10 with the fixing pins for alignment and fixation of the nozzle body 1 fall away relative to the nozzle holder or injector, thereby increasing, inter alia, the vibration resistance of the nozzle body 1.

Figure 2a shows a schematic representation of nozzle bodies according to the invention with possible forms of marking.

In this preferred embodiment of the present invention, the mark is a recess in the outer wall of the nozzle body. There are six possible variants of this embodiment shown with recess. In each case a section of a nozzle body is shown. For example, the first variant 11 shows the section of a nozzle body 17 from the outside. The upper sealing surface 19 is connected to a nozzle holder or injector, not shown. Downstream 18, the nozzle body 17 tapers, the lower conical end is not shown. The upper sealing surface 19 of the nozzle body 17 does not have the pin holes used in the prior art. Instead, the nozzle body 17 in its outer wall erfmdungsgemäß according to a marking in the form of a recess 20. Through this recess 20, the nozzle body 17 has a unique mark, by means of which the nozzle body 17 can be aligned so that it after the Clamping to a nozzle holder or injector is in the correct position. It is assumed that the recess 20 has been mounted in a precisely known position relative to the internal structure of the nozzle body 17. The aim of the alignment of the nozzle body 17 relative to the nozzle holder or injector is that, for example, the inlet holes in the nozzle body 17 and the nozzle holder or injector (or in an integrated nozzle holder or injector washer) are brought exactly to coincidence and that the nozzle body 17th centered on the body of the nozzle holder or injector. The accuracy of the fixation is increased at constant tolerances by using the recess 20 instead of pin holes. The fixing accuracy is greater, the smaller the maximum angle of rotation of the nozzle body relative to the nozzle holder or injector, after the two components together were fastened. The reason for increasing the fixing accuracy in the present invention is that the recess 20 is located at a greater distance from the central axis of the nozzle body 17 than the fixing holes in the prior art. Therefore, an inaccuracy in the position of the recess 20 in the form of a smaller angle of rotation affects than the same inaccuracy in the position of a fixing hole, which is closer to the rotational axis of the nozzle body 17.

FIG. 2b shows an embodiment of the recess 20 with a triangular cross-section.

Advantageously, this results for the fuel injection valve according to the invention, that a possible internal leakage or under pressure of the pin holes is not possible by eliminating the pin holes. This unfavorable case, by contrast, can not be safely ruled out in the prior art and increases the tensions in the nozzle body 1. Further, it follows from the omission of the pin holes in the fuel injection valve according to the invention that 4 holes and 2 pins can be saved, so that there is a cost advantage.

A)

optisches Erfassen der Position der mindestens einen Markierung;

B)

Drehen des Düsenkörpers 17 um seine Symmetrieachse bis die Position der Markierung mit einer vorgegebenen Position übereinstimmt und

C)

Festspannen der Einspritzdüse an dem bereits ausgerichteten Düsenhalter oder Injektor.

Furthermore, the present invention relates to a method for aligning the nozzle body 17 with at least one mark 20 relative to the nozzle holder or injector during assembly of a fuel injection valve according to the invention. The nozzle holder or injector should already be aligned in a certain position. The process according to the invention comprises the following process steps:

A)

optically detecting the position of the at least one marker;

B)

Rotating the nozzle body 17 about its axis of symmetry until the position of the marker coincides with a predetermined position, and

C)

Clamping the injector to the already aligned nozzle holder or injector.

The predetermined position of the marker 20 is thereby set so that the nozzle body 17 is aligned exactly after clamping on the nozzle holder or injector. The depth of the mark 20 must be chosen in this method so that there is a contrast to the rest of the nozzle body 17, which is used by an optical medium used for the optical detection of the position of the at least one mark 20 (eye, camera). .) can be detected.

Preferably, the optical detection of the positions of the at least one marker 20 is carried out with the aid of a camera, wherein images captured by the camera are forwarded to an image processing program which determines the current position of the at least one marker. By using a camera and an image processing program, the optical detection of the position of the marker 20 can be automated and integrated into a machine production process. The automation of the assembly of fuel injection valves according to the invention can be further achieved in that the rotation of the nozzle body 17 about its axis of symmetry automatically occurs when the determined by the image processing program current position of the at least one mark deviates from the predetermined position. This automatic rotation can be performed, for example, by a robot arm or a turntable on which the nozzle body 17 is located.

Figure 3 shows a schematic representation of a nozzle body according to the invention with a key surface and an associated assembly tool.

On the left side of the figure, a section through an injection nozzle 21 and a mounting tool 22 is shown and on the right side a view of the same parts from the outside. Further, on both sides of the clamping nut 23 is shown, which serves to fasten the nozzle body 24 of the injection nozzle 21 centrally in the (not shown nozzle holder or injector). On the nozzle body 24 is a key surface 25, which causes the nozzle body 24 fits into a form-fitting manner in the mounting tool 22 only in a certain position. The key surface 25 is preferably located on the outside of the nozzle body 24. The pin holes that serve in the prior art for alignment and fixation of the nozzle body 24 are not present in the present invention in the sealing surface 26 of the nozzle body 24. In the case of the key surface 24 is in this case a straight surface which interrupts the curved lateral surface of the nozzle body 24. However, the key surface 24 may have any other shape that fits positively into an associated mounting tool 22. It is located at a specific position of the nozzle body 24.

A)

Aufsetzen des Düsenkörpers 24 auf das Montagewerkzeug 22;

B)

Drehen des Düsenkörpers 24, bis er formschlüssig in das Montagewerkzeug 22 paßt und

C)

Festspannen der Einspritzdüse 21 an dem Düsenhalter oder Injektor.

Furthermore, the present invention relates to a method for aligning the nozzle body with at least one key surface 25 relative to the nozzle holder or injector during assembly of a fuel injection valve according to the invention. The nozzle holder or injector and the assembly tool 22 are aligned in a specific position. The process according to the invention comprises the following process steps:

A)

Placing the nozzle body 24 on the mounting tool 22;

B)

Turning the nozzle body 24 until it fits positively into the mounting tool 22 and

C)

Clamping the injector 21 to the nozzle holder or injector.

The orientation of the nozzle holder or injector and the mounting tool 22 is selected so that the nozzle body 24 is aligned exactly after clamping with the clamping nut 23 on the nozzle holder or injector (or on the integrated into the nozzle holder or injector washer).

As a further advantage of the fuel injection valve according to the invention, it follows that a possible internal leakage or pressure infiltration of the pin holes is not possible by eliminating the pin holes. On the other hand, this unfavorable case can not be reliably ruled out in the prior art and considerably increases the stresses in the nozzle body 1 (by about 25%, which can result in premature material fatigue). These disadvantages of the prior art are advantageously avoided by the present invention. Furthermore, the elimination of the pin holes in the fuel injection valve according to the invention is a cost advantage, since 4 holes and 2 pins can be saved.

FIG. 4 shows a holding body / nozzle body connection by means of a nozzle retaining nut with an enlarged bore.

The nozzle body 1 shown in Figure 4 comprises a bore 2, in which the nozzle needle 3 is slidably received. At the lower end of the nozzle needle, this has a sealing cone 4, which cooperates with a chronic sealing surface 5 of the nozzle body 1. In an axial movement of the nozzle needle 3 within the bore 2 injection openings are released or closed in the combustion chamber, not shown here a self-igniting internal combustion engine. The nozzle body 1 comprises an inlet bore 7, which opens into a pressure chamber 8, which surrounds the nozzle needle 3 in the region of a pressure stage. The nozzle body 1 is surrounded by a nozzle retaining nut 23, whereby the sealing surface 9 is pressed against a corresponding end face 31 of a holding body 30.

The recess or marking 20 shown in FIGS. 2 a) to 2 f) in the upper region of the nozzle body 17 identified there by reference numeral 17 is located in accordance with FIG 4 in the lower region of a shaft 37 of the nozzle body 1. The shaft 37 of the nozzle body 1 formed in a second shaft diameter 41 is enclosed by a clamping tool 42 which has a viewing window 43 in the region of the marking 20. According to the embodiment variant shown in FIG. 4, the shaft 37 is formed with a region 38 that is thickened in terms of its diameter.

The nozzle retaining nut 23 comprises a ring-shaped release 34 into which the upper part of the clamping tool 42 protrudes and the nozzle body 1 is supported on a shoulder 44. Via the shoulder 44, the biasing force acting in the axial direction is introduced into the nozzle body 1, with which the nozzle body 1 is pressed against the end face 31 of the holding body 30. Once the required preload force is reached, the assembly of the nozzle lock nut 23, which transmits no torque during assembly, but only by the clamping tool 42 applied biasing force is maintained upon reaching the Sollanzugsdrehmomentes, so that a sealing contact of the sealing surface 9 to the nozzle body 1 assigning end face 31 of the holding body 30 is achieved. In the embodiment variant shown in FIG. 4, the first diameter of the nozzle retaining nut 23, with which it encloses the clamping tool 42, is identified by reference numeral 35.

The marking 20 in the lower region of the shaft 37 is preferably mounted in the spray-hole production and can, for. B. be procured as an erosion or laser point, which allows the unique allocation of the injection holes for supply hole. This mark 20 is designed to be machine readable and z. B. be identified via a camera system, an optical system or with the naked eye. On the nozzle body 1, the marking 20 can be attached to any circumferential location on the circumference of the shaft 37, so that an alignment of the nozzle body 1 is unnecessary. During assembly, the angular orientation of the nozzle body 1 to the holding body 30 by inserting or twisting takes place in a angular and angle-centered clamping tool 42 relative to the holding body 30. The proper position of the nozzle body 1 in the holding body 30 is detected by scanning the mark 20 on the shaft 37 of the nozzle body 1 through the viewing window 43, which is arranged in the wall of the clamping tool 42. The bracing of the composite of holding body 30, which contains a further inlet bore 33 communicating with the inlet bore 7 of the nozzle body 1, is effected by applying a corresponding axial force effecting a good sealing effect. This is introduced into the composite of holding body 30 and nozzle body wherein the nozzle body 1 is supported on a collar on the shoulder 44 of the clamping tool 42. To ensure that only the nozzle body 1 through the Shoulder 44 is supported, the nozzle body 1 enclosing the nozzle lock nut 23 comprises a release 34, which is generated by a corresponding formation of the first diameter 35 of the nozzle lock nut 23. To the axial direction strained composite of holding body 30 and nozzle body 1, the nozzle lock nut 23 is then screwed to the stop, which transmits no torque, but is only burdened by a relatively low Gewindereibmoment. The threaded clamping nut 23 maintains the axial bias and causes a sealing abutment of the end face 31 of the holding body 30 on the sealing surface 9 of the nozzle body 1. Subsequently, the clamping tool 42 is pulled out of the release 43 in the lower region of the nozzle retaining nut 23. In an advantageous manner, an annular groove 32 can be formed on the holding body 30 in order to discharge the pretensioning force acting in the axial direction as early as possible from the injection valve. In which ring-shaped on the holding body 30 extending annular groove 32, a hold-down engage, over which the force is divisible.

FIG. 5 shows a holding body / nozzle body connection with, in which the nozzle body 1 has a reduced shaft diameter.

In this embodiment of the solution proposed according to the invention, the release 34 is formed in the lower region of the nozzle retaining nut 23 in a second diameter 36. In contrast to the embodiment variant shown in FIG. 4, the shaft 37 of the nozzle body 1 is designed in a second diameter 41 as shown in FIG. As a result, the clamping tool 42 surrounding the shaft 37 of the nozzle body 1 can also be formed in a smaller diameter. Due to the small diameter of the shaft 37, the second diameter 36 of the bore in the nozzle lock nut 23 is also formed smaller, resulting in an investment of the shoulder 44 of the clamping tool 42 on the nozzle body and the nozzle body 1, which is more on the pressure chamber 8. Also with the embodiment shown in Figure 5, the introduction of a force acting in the axial direction biasing force in the composite of holding body 30 and nozzle body 1, so that on the support 39, ie the contact area between the end face 31 of the holding body 30 and the sealing surface 9 of the nozzle body 1 a very good sealing effect is achieved. Also in this case, the nozzle lock nut 23 is screwed onto an external thread formed on the holding body 30 and only has to overcome a slight thread breaking moment. After attachment, ie bias to a required minimum torque, the nozzle retaining nut 23 takes over the maintenance of the acting in the axial direction biasing force and holds the end face 31 and the sealing surface 9 in sealing engagement with each other. Thereafter, a removal of the clamping tool 42 from the release 34 of the nozzle retaining nut 23 take place. optional can be inserted in the release 34 for the clamping tool 42, a clamping ring or the like, or a one-time tool head are inserted to limit a too large in the tool release gas damage volume.

LIST OF REFERENCE NUMBERS

1

nozzle body

2

drilling

3

nozzle needle

4

Sealing cone of the nozzle needle

5

Conical sealing surface of the nozzle body

6

spiracles

7

inlet bore

8th

pressure chamber

9

Sealing surface of the nozzle body

10

pinhole

11

First variant

16

Further variant

17

nozzle body

18

downstream

19

Upper sealing surface

20

recess

21

injection

22

assembly tool

23

Clamping nut (DSM)

24

nozzle body

25

key area

26

sealing surface

30

holding body

31

End face holding body

32

Ringnuthaltekörper

33

inlet bore

34

Release of nozzle retaining nut for tool (42)

35

First dia meter

36

Second diameter

37

Shaft nozzle body

38

Community level

39

edition

40

First shaft diameter

41

Second shaft diameter

42

clamping tool

43

window

44

Shoulder clamping tool

Claims (6)

1. Method for orienting the nozzle body (1, 17) in relation to the nozzle holder or injector during the mounting of a fuel injection valve for internal combustion engines, with an injection nozzle firmly clamped on a nozzle holder or injector and comprising a nozzle body (1, 17) and a nozzle needle (3), the nozzle needle (3) being axially displaceable in a bore (2) in the nozzle body (1, 17), the nozzle body (1, 17) containing at least one marking or one key face for orienting the nozzle body (1, 17) in relation to the nozzle holder or injector, the nozzle holder or injector being oriented in a specific position, with the following method steps:

   A) optical detection of the position of the at least one marking (20);

   B) rotation of the nozzle body (1, 17) about its axis of symmetry until the position of the marking (20) coincides with a predetermined position, and

   C) firm clamping of the injection nozzle on the already oriented nozzle holder (30) or injector,

   characterized in that an axial prestressing force causing the adjustment of the holding body (30) in the nozzle body (1) is introduced by a tool (42) led into the clearance (34) into the composite structure consisting of holding body (30)/nozzle body (1), before the mounting of a tension nut (23) connecting the holding body (30) and the nozzle body (1) takes place.
2. Method according to Claim 1, characterized in that the optical detection of the position of the at least one marking takes place with the aid of a camera, images detected by the camera being transferred to an image processing program which determines the current position of the at least one marking (20).
3. Method according to either one of Claims 1 and 2, characterized in that the rotation of the nozzle body (1, 17) about its axis of symmetry takes place automatically when the current position of the at least one marking (20) determined by the image processing program deviates from the predetermined position.
4. Method according to one of Claims 1 to 3, characterized in that the position of the marking (20) is detected through an inspection window (43) of a clamping tool (42).
5. Method according to one of Claims 1 to 4, characterized in that the axial prestressing force is conducted out of the composite structure consisting of holding body (30)/nozzle body (1) via a holding-down device engaging on the annular groove (32) of the holding body (30).
6. Method according to one of Claims 1 to 5, the nozzle holder or injector and a mounting tool (22) being oriented in a specific position, with the following method steps:

   A) placing of the nozzle body (24) onto the mounting tool (22) ;

   B) rotation of the nozzle body (24) until it fits positively into the mounting tool (22), and

   C) firm clamping of the injection nozzle (21) on the nozzle holder or injector.

Images