DE102022206350A1 - Gas injector with very good damping properties during operation - Google Patents

Abstract

The present invention relates to a gas injector for blowing in a gaseous fuel, comprising a magnetic actuator (2) with an armature (20), an inner pole (21) and a coil (22), a closing element (3) with a valve needle (30), wherein the closing element (3) releases and closes a gas path (14) on a sealing seat (11) arranged at a first end of the gas injector, the anchor (20) being connected to the closing element (3); a closed lubricant space (4) which is filled with a lubricant and in which the armature (20) is arranged, the lubricant ensuring lubrication of the armature (20), and a restoring element (10) which the closing element (3) in a closed starting position is left behind, the lubricant space (4) having a first flexible sealing element (51) and a second flexible sealing element (52), an opening brake device (5), which loads the first flexible sealing element (51) and the second flexible sealing element ( 52) is reduced during the opening process, and a closing brake device (6), which reduces a load on the first flexible sealing element (51) and the second flexible sealing element (52) and the sealing seat (11) during the closing process.

Description

State of the art

The present invention relates to a gas injector for blowing in a gaseous fuel, in particular hydrogen or natural gas or the like, with a compact design and very good damping properties both during an opening process and during a closing process of a closing element of the gas injector. The gas injector is designed in particular for direct injection into a combustion chamber of an internal combustion engine.

Gas injectors are known from the prior art in different designs. One problem area with gas injectors is, due to their principle, that due to the gaseous medium to be injected, no lubrication through the medium is possible, as is possible, for example, with fuel injectors that inject gasoline or diesel. In order to enable the mobility of the closing element, in particular a valve needle, it is known to use flexible sealing elements, such as bellows. During operation, this makes it possible for vibration excitations to occur due to the gaseous fuel, which can in particular negatively influence the actuation of the closing element in the opening or closing process.

Disclosure of the invention

The gas injector according to the invention for blowing in a gaseous fuel with the features of claim 1, however, has the advantage that vibration excitation of components of the gas injector can be suppressed both during the opening process and during the closing process.

This results in very precise adherence to specified injection quantities, opening times and closing times when operating the gas injector. In particular, excitation of longitudinal vibrations of a closing element can be prevented. This avoids damage to flexible elements, such as metal bellows, in the gas injector, which ensure the mobility of the closing element in the axial direction of the gas injector. This is achieved according to the invention in that the gas injector comprises a magnetic actuator with an armature, an inner pole and a coil. Furthermore, the gas injector comprises a closing element with a valve needle, which opens and closes a gas path for the gaseous fuel at a sealing seat. The sealing seat is arranged at a first end of the gas injector and the gas injector is preferably an injector that opens to the outside. The anchor is connected to the closing element. Furthermore, a closed lubricant space is provided, which is filled with lubricant and in which the movable anchor is arranged. The lubricant ensures that the armature is lubricated so that no wear occurs on the armature during operation. The lubricant space here comprises at least a first flexible sealing element, in particular a bellows, which seals the lubricant space from the gas path and thus ensures the axial mobility of the closing element, as well as a second flexible sealing element which provides a compensation space for the lubricant space. Furthermore, the gas injector comprises a restoring element, in particular a closing spring in the form of a cylinder spring, wherein the restoring element returns the closing element to a closed starting position. The gas injector further comprises an opening brake device, which reduces a load on the first flexible sealing element and the second flexible sealing element during the opening process, and a closing brake device, which reduces a load on the first flexible sealing element and the second flexible sealing element as well as the sealing seat during the closing process.

The opening brake device reduces a load on the valve assembly and in particular on the first flexible element, which is arranged on the closing element. The opening brake device also compensates for the fact that in gas injectors a stroke of the closing element is very large compared to gasoline or diesel fuel injectors, which tends to increase the susceptibility of components of the gas injector to vibration and leads to high loads and wear on the opening stop surfaces between the armature and the inner pole leads. The invention can significantly counteract this.

The closing brake device also ensures during the closing process that the load on the flexible sealing elements remains low and that the closing element does not hit the sealing seat with too much force, which on the one hand can lead to damage to the components and on the other hand so-called “bouncing” may occur in which the closing element After closing, it briefly lifts off the sealing seat again due to the force of the closing process, so that additional gas is briefly introduced into the combustion chamber, which cannot be used.

The subclaims show preferred developments of the invention.

More preferably, the gas injector comprises an anchor bolt, which is in the lubricant space is arranged and/or is connected to the closing element. The opening brake device and/or the closing brake device are arranged on the anchor bolt. This can ensure a particularly compact design of the gas injector. By positioning the opening brake device and/or the closing brake device inside the lubricant chamber, hydraulic damping can also be achieved both in the opening process and in the closing process.

The opening brake device preferably comprises a first piston, a first damping spring and a first damping space. Further preferably, the closing brake device comprises a second piston, a second damping spring and a second damping space. The opening brake device further preferably comprises a stop ring, which is preferably arranged on the anchor bolt and only enables damping in the opening process with a delay. This ensures that the damping during the opening process only begins towards the end of the opening stroke.

In order to achieve a particularly compact structure, the second piston is preferably arranged at least partially, preferably completely, in the first piston.

In order to enable a further compact structure of the arrangement, the anchor bolt is preferably passed through the first and second pistons. The first and second pistons of the two braking devices are therefore annular.

More preferably, the first piston has a shoulder on an inner circumference as a stop for the second piston. This further increases the integration of the first and second pistons into each other, so that the installation space and structure of the gas injector can be further reduced.

More preferably, the second piston is arranged with play on the anchor bolt. This achieves a rapid onset of the damping effect, especially during the closing process.

Preferably, a spring force of the first damping spring of the opening brake device is greater than a spring force of the second damping spring of the closing brake device. The spring force of the first damping spring is preferably at least twice as large as the spring force of the second damping spring. This can also ensure that the damping during the opening process only begins towards the end of the complete opening stroke.

Further preferably, the anchor bolt has a shoulder on which the second piston of the closing brake device is arranged. In order to provide as small a diameter as possible for the lubricant space, the anchor preferably has passage openings for the lubricant.

More preferably, the anchor bolt is guided in a guide disk. The guide disk preferably also serves to support the first damping spring of the opening brake device.

The guide disk further preferably has an axially projecting ring shoulder, which preferably projects at least partially into the anchor, which has a corresponding recess.

The first damping spring is preferably arranged between the guide disk and the first piston. The second damping spring is preferably arranged between a storage body, which is arranged in the lubricant space, and the second piston.

The first and second flexible elements are preferably a bellows, in particular a metal bellows. A first diameter of the first flexible element is preferably smaller than a second diameter of the second flexible element.

Further preferably, the gas injector comprises a first, second and third needle guide, which guide the valve needle during the opening and closing processes. Here, the first and second needle guides are arranged in the gas path and the third needle guide is arranged in the lubricant space. The restoring element is also arranged in the lubricant space. Thus, movements of the restoring element and the third needle guide, which are lubricated by the lubricant of the lubricant space, produce no or at most minimal, negligible wear. The first and second needle guides, which are arranged in the gas path, are therefore located outside the lubricant space. If a tilting moment is exerted on the valve needle by the restoring element during operation, this tilting moment can be safely absorbed by the two first and second needle guides arranged in the gas path. This prevents the valve needle from bending, which could be caused by the tilting moment that may occur, through the first and second needle guides. As a result, the sealing seat remains closed in all operating situations and tilting of the valve needle on the sealing seat and thus an insufficient closing process can be prevented. This means that the valve needle has a double guide safely guided outside the lubricant room and a guide in the lubricant room.

Preferably, a first distance A1 between the first and second needle guides in the axial direction X-X of the gas injector is smaller than a second distance A2 between the second and third needle guides in the axial direction X-X. This ensures that possible tilting moments are absorbed particularly well by the first and second needle guides. The second distance A2 is preferably at least twice as large, more preferably at least three times as large, as the first distance A1.

Further preferably, the first and/or second and/or third needle guide each have an annular guide region which is connected to the valve needle of the closing element via webs, such that openings for fluid passage are present between the webs. This is particularly advantageous on the first and second needle guides, which are arranged in the gas guide area of the gas injector in order to allow the largest possible quantities of gas to flow through the first and second guide areas when the gas injector is open. The annular guide area is preferably closed along the entire circumference. In order to keep friction as small as possible during the opening and closing process of the closing element, a width of the annular guide area is chosen to be as small as possible. Particularly preferably, three webs are provided, which connect the valve needle to the annular guide area. The webs are preferably arranged at equal distances along the circumference.

According to a particularly preferred embodiment of the invention, the webs between the valve needle and the annular guide areas are arranged at an acute angle to the annular guide area. This makes it possible for a flow cross section to be increased in the area of the guides, which is particularly advantageous for the first and second needle guides, which are located in the gas guide area. The webs are preferably arranged in the direction of flow through the openings after the guide area. Alternatively, the webs between the valve needle and the annular guide area of the needle guides are arranged at a right angle to the valve needle.

According to a particularly preferred embodiment of the invention, a plate is also arranged on the valve needle, to which the first flexible sealing element is fixed. This makes it possible to achieve a simple connection between the closing element and the first flexible sealing element, which seals the lubricant space.

The first and second needle guides are preferably guided on the same component. The component is preferably a cylindrical valve body, on which the sealing seat is also arranged. This makes it possible for the guide surfaces for the first and second needle guides to be produced in one clamping, which offers great advantages in terms of manufacturing technology and further reduces manufacturing costs.

In order to further reduce the number of components, the third needle guide is preferably also set up to support the restoring element, which is arranged in the lubricant space. The third needle guide can preferably be designed as a plate with openings for the lubricant during the opening and closing process of the closing element.

The closing element with the three needle guides is preferably designed as a one-piece component. In this way, weld seams or the like can be avoided, which are often a source of contamination during operation of the gas injector, which can then lead to tightness problems at the sealing seat or the like. A multi-part closing element made up of individual elements welded together is also preferred for reducing machining volume and saving manufacturing costs.

The first and/or second flexible sealing element is preferably a metal bellows. On the one hand, the metal bellows provides very good mobility in order to enable the axial movements of the closing element and, on the other hand, the metal bellows can be arranged as close as possible to the hot combustion chamber of the internal combustion engine. This allows the axial length of the gas injector to be further reduced. Alternatively, the first flexible sealing element is a plastic bellows or a membrane or a rubber element.

In order to further reduce an axial length of the gas injector, an electrical connection of the gas injector and/or a gas inlet of the gas injector is preferably arranged laterally on the gas injector.

The gas injector further preferably has a conical sealing seat. Preferably, the closing element comprises a sealing disk at an end directed towards the combustion chamber, which exposes one or more through openings at a sealing seat. The gas injector is preferably designed as an injector that opens to the outside. This allows a sealing fit to be provided which blows the fuel gas into the combustion chamber in a hollow cone shape.

An oil, in particular a synthetic oil or mineral oil, is preferably used as the lubricant. Alternatively, a liquid fuel, in particular diesel or gasoline, is used. Alternatively, a grease is used as a lubricant.

Short description of the drawing

• 1 eine schematische Schnittansicht eines Gasinjektors gemäß einem ersten Ausführungsbeispiel der Erfindung, und
• 2 eine schematische Teil-Schnittansicht des Gasinjektors von 1.

An embodiment of the invention is described in detail below with reference to the accompanying drawing. In the drawing is:

• 1 a schematic sectional view of a gas injector according to a first embodiment of the invention, and
• 2 a schematic partial sectional view of the gas injector from 1 .

Preferred embodiment of the invention

Below is with reference to 1 and 2 a gas injector 1 according to a first preferred embodiment of the invention is described in detail.

How out 1 As can be seen, the gas injector 1 for introducing a gaseous fuel comprises a magnetic actuator 2, which moves an outwardly opening closing element 3 from a closed state to an open state. The 1 shows the closed state of the gas injector.

The magnetic actuator 2 includes an armature 20, which is connected to the closing element 3 by means of an anchor bolt 24. Furthermore, the magnetic actuator 2 includes an inner pole 21, a coil 22 and a magnet housing 23, which ensures a magnetic inference of the magnetic actuator.

Furthermore, the gas injector 1 comprises a main body 7 with a gas inlet 70 through which the gaseous fuel is supplied. The gas inlet 70 is arranged on the main body 7 in the axial direction X-X. The main body 7 is connected to a valve housing 8, in which the magnetic actuator 2 is arranged.

The valve housing 8 is adjoined by a housing sleeve 19, at the free end of which a sealing seat 11 is provided on a valve seat component 93, on which the closing element 3 opens and closes a passage for the gaseous fuel.

In 1 an electrical connection 13, which is guided through the main body 7 to the magnetic actuator 2, is shown schematically. The electrical connection 13 is arranged laterally on the main body 7.

The reference number 10 denotes a restoring element for the closing element 3 in order to return it to the in 1 to the closed state shown.

In 1 A gas flow is also shown as a gas path 14 through the gas injector 1. The gas flow begins at the gas inlet 70 and is then diverted and leads through the main body 7. The gas flow 14 continues past an outer area of the magnetic actuator 2 through a filter 15 to the sealing seat 11. Corresponding openings are provided in the respective components , what a 1 not all are shown.

When the gas injector 1 is opened, the gaseous fuel then flows past the outer circumference of the magnetic actuator 2 and the opened sealing seat 11 into a combustion chamber 100 of an internal combustion engine, which in 1 is indicated by the arrows A.

The closing element 3 comprises a valve needle 30 with a seat plate 30a, which is arranged at the end of the closing element directed towards the combustion chamber. The sealing seat 11 is formed between the seat plate 30a and the valve seat component 93, which is essentially a cylindrical tube.

The closing element 3 further comprises a first needle guide 31, a second needle guide 32 and a third needle guide 33. The two needle guides 31, 32 are preferably formed in one piece with the valve needle 30.

The gas injector 1 further comprises a closed lubricant space 4. The closed lubricant space 4 is completely or partially filled with a liquid lubricant, for example oil.

How out 1 As can be seen, the lubricant space 4 is defined by a first flexible sealing element 51, the inner pole 21, a sleeve 18, a storage body 17 and a second flexible sealing element 52. The first and second flexible sealing elements 51, 52 are each designed as metal bellows.

The closing element 3 also includes a plate 34 on which the first flexible sealing element 51 is supported.

A plurality of connecting bores 77 are formed in the storage body 17, which connect the interior region of the second flexible sealing element 52 with the other regions of the lubricant space 4. How out 1 As can be seen, the second flexible sealing element 52 has a relatively large diameter, which is larger than the diameter of the first flexible sealing element 51. Furthermore, a storage pressure spring 40 is provided, which is supported on the main body 7.

The second flexible sealing element 52 serves as a compensation space for the lubricant located in the lubricant space 4. This allows pressure fluctuations in the lubricant chamber 4 to be compensated for.

The first flexible sealing element 51 is also fixed directly to the closing element 3 on the plate 34 and connected to a guide sleeve 35 at the other end. The third needle guide 33 is guided within the guide sleeve 35.

The lubricant chamber 4 thus has two flexible sealing elements 51, 52 and the storage pressure spring 40. The storage pressure spring 40 exerts a certain preload, for example 1 × 10 ⁵ Pa, on the lubricant located in the lubricant space 4. If displacement of the lubricant occurs during an opening process due to the stroke of the closing element 3 or also due to thermal expansion or cooling of the lubricant, any overpressure/negative pressure that may arise inside the lubricant space 4 can be caused by deflection on the second flexible sealing element 52 in conjunction with a contraction of the Storage pressure spring 40 can be balanced. Thus, the first flexible sealing element 51 cannot exert any unwanted force on the closing element 3 acting via the bellows effective surface.

The anchor bolt 24 with the anchor 20 fixed to it is also arranged in the closed lubricant space 4. Since the lubricant space 4 is filled with a lubricant, for example a liquid fuel such as gasoline or diesel or a grease or the like, the armature 20 is continuously lubricated. This makes it possible to compensate for the problem that occurs in the prior art with gaseous fuels, that there is a lack of lubrication of the moving parts.

The gas injector 1 further comprises an opening brake device 5, which reduces a load on the first and second flexible sealing elements 51, 52 and the anchor stop during the opening process, and a closing brake device 6, which reduces a load on the first and second flexible sealing elements 51, 52 and the sealing seat 11 during the closing process reduced.

More specifically, the opening brake device 5 comprises a first piston 53, a damping spring 54, a first damping space 55 and a stop ring 56, which is arranged on the anchor bolt 24 at its free end, which faces away from the sealing seat 11.

The closing brake device 6 comprises a second piston 63, a second damping spring 64 and a second damping space 65.

Like in particular 2 As can be seen, the opening brake device 5 and the closing brake device 6 are arranged within a central recess in the storage body 17. Thus, the opening brake device 5 and the closing brake device 6 are arranged on a side of the armature 20 facing away from the sealing seat 11 in the lubricant space 4.

How out 2 As can be seen, the first damping spring 54 is supported between a stationary guide disk 9, which is supported in a sleeve 18, which connects the inner pole 21 and the storage body 17, and the first piston 53. The first damping spring 54 is arranged in the first damping space 55. Lubricant is also present in the first damping space 55, as shown 2 It can be seen that the anchor bolt 24 is guided in the guide disk 9 and lubricant enters the damping space 55 via this guide gap.

The guide disk 9 has a shoulder 91 which projects in the axial direction towards the sealing seat 11. Here, a correspondingly designed recess 20a is provided in the armature 20, so that a volume of the lubricant in this area of the gas injector is reduced.

The closing brake device 6 is arranged at the end of the anchor bolt 24 facing away from the sealing seat 11. Here, the second damping spring 64 is arranged in the second damping space 65. The second damping spring 64 is arranged between the storage body 17 and the second piston 63.

How further? 2 As can be seen, the second piston 63 is partially arranged within the first piston 64. Here, a shoulder 25 is provided on the anchor bolt 24, which serves as a stop for the second piston 63. In 2 the reference number H1 is the maximum stroke of the armature 20, which is equal to the maximum opening path of the closing element 3, shown as the first gap H 1. A second gap H2 is provided between the stop ring 56 and the second piston 63. A third gap H3 is provided between the second piston 63 and the first piston 53 in the closed position.

The function of the gas injector 1 is as follows. Starting from the in the 1 and 2 In the closed position shown, the coil 22 is energized, whereby the armature 20 moves in the direction of arrow B (cf. 2 ) is pulled to the inner pole 21. Since the anchor 20 is firmly connected to the anchor bolt, the anchor bolt 24 is also moved in the direction of arrow B, whereby the closing element 3 lifts off the sealing seat 11 and an injection begins.

How out 2 As can be seen, after the second gap H2 has been covered, contact is established between the stop ring 56 and the second piston 63, so that the second piston 63 is also moved in the direction of arrow B when current is continued. This movement of the second piston 63 is also supported by the second damping spring 64. With further energization, the second piston 63 moves in the direction of arrow B, so that the third gap H3, which was present between the second piston 63 and the first piston 53, is overcome. Then the opening brake device 5 is activated. Here, the first piston 53 is moved further in the direction of arrow B, against the spring force of the first damping spring 54. In this case, lubricant must also be displaced from the first damping space 55, whereby braking and damping of the opening process is achieved.

The lubricant from the first damping chamber 55 flows through gaps between the first piston 53 and the anchor bolt 24 and the second piston 63 and the anchor bolt 24 into the second damping chamber 65 and through gaps between the first damping piston 53 and the storage body 17 and the first damping piston 53 and the second Damping piston 63 into the second damping space 65. There is also a flow across gaps between the anchor bolt 24 and the guide disk 9. It should be noted that the first piston 53 and the second piston 63 are each arranged with play on the anchor bolt 24 .

As soon as the injection is to be ended, the current supply to the magnetic actuator is stopped, so that the restoring element 10 moves the closing element 2 and thus also the anchor bolt 24 back in the direction of the in the 1 and 2 shown starting position. Since the second piston 63 rests on the shoulder 25 on the anchor bolt 24, the second piston 63 is also moved in the direction of arrow C during the reset. Here, the second piston 63 must be moved against the spring force of the second damping spring 64 and lubricant must flow back from the second damping space via the gap between the first and second pistons and the anchor bolt 24 to the first damping space 53. This creates damping during the closing process.

It should be noted that during the closing process a damping effect only occurs when the first piston 53 rests on a shoulder 17a of the storage body 17. The second piston 63 of the closing brake device 6 then lifts off the shoulder 25 on the anchor bolt 24 and increases the pressure in the second damping space 65 in order to effect the damping during the closing process.

The play between the two pistons and the anchor bolt 24 increases the restoring speed of the two pistons. It should be noted that instead of the play between the pistons and the anchor bolt 24, corresponding bores can also be formed in the first and second pistons, but this is more complex in terms of production technology than providing play for the anchor bolt 24.

The spring force for resetting the first piston 53 is preferably twice as high as the spring force for resetting the second piston 63. The gas injector according to the invention can thus stimulate longitudinal vibrations of the first flexible sealing element 51 (first bellows) both during the opening process and during the closing process ) and the second flexible sealing element 52 (second bellows). Since such a longitudinal vibration would increase the number of bellows deflections, the invention can significantly increase the service life of the flexible sealing elements. The closing brake device 6 also prevents the closing element 3 from striking too strongly against the sealing seat 11 during the closing process. This reduces wear on the closing element and/or the sealing seat when closing the gas injector.

The in 1 Gas injector 1 shown is balanced in terms of pressure force. This means that the closing element 3 is connected to the guide sleeve 35 via the first flexible sealing element 51, the first flexible sealing element 51, which is designed as a metal bellows, having a mean diameter which is equal to a diameter at the sealing seat 11 on which the closing element 3 seals. This results in no pressure force on the closing element 3, so that a magnetic force, which opens nen of the closing element 3 is necessary, can be kept very small and is in particular independent of a pressure of the gaseous fuel.

Claims (14)

Gas injector for injecting a gaseous fuel, comprising: - a magnetic actuator (2) with an armature (20), an inner pole (21) and a coil (22), - a closing element (3) with a valve needle (30), the closing element (3) releasing and closing a gas path (14) on a sealing seat (11) arranged at a first end of the gas injector, the armature (20) being connected to the closing element (3) is connected, - a closed lubricant chamber (4) which is filled with a lubricant and in which the armature (20) is arranged, the lubricant ensuring lubrication of the armature (20), and - a restoring element (10), which returns the closing element (3) to a closed starting position, - wherein the lubricant space (4) has a first flexible sealing element (51) and a second flexible sealing element (52), the first flexible sealing element (51) being arranged on the closing element (3) and the lubricant space (4) opposite the gas path (14 ) seals, and the second flexible sealing element (52) is arranged on an area of the gas injector opposite the sealing seat (11), - an opening brake device (5), which reduces the load on the first flexible sealing element (51) and the second flexible sealing element (52) during the opening process, and - A closing brake device (6), which reduces the load on the first flexible sealing element (51) and the second flexible sealing element (52) and the sealing seat (11) during the closing process. Gas injector after Claim 1 , further comprising an anchor bolt (24) which is arranged in the lubricant space (4) and is connected to the closing element (3), wherein the opening brake device (5) and / or the closing brake device (6) are arranged on the anchor bolt (24). Gas injector after Claim 2 , - wherein the opening brake device has a first piston (53), a first damping spring (54) and a first damping space (55) and a stop ring (56) on the anchor bolt (24) and - wherein the closing brake device (6) has a second piston (63 ), a second damping spring (64) and a second damping space (65). Gas injector after Claim 3 , wherein the second piston (63) is at least partially arranged in the first piston (53). Gas injector after Claim 3 or 4 , wherein the anchor bolt (24) is passed through the first piston (53) and the second piston (63). Gas injector after Claim 4 or 5 , wherein the first piston (53) has a shoulder on an inner circumference as a stop for the second piston (63). Gas injector after one of the Claims 3 until 6 , wherein the first piston (53) and / or the second piston (63) is arranged with play on the anchor bolt (24). Gas injector after one of the Claims 3 until 7 , wherein a spring force of the first damping spring (54) is greater than a spring force of the second damping spring (64). Gas injector after one of the Claims 3 until 8th , wherein the anchor bolt (24) has a shoulder (25) as a stop for the opening brake device (5). Gas injector after one of the Claims 3 until 9 further comprising a guide disk (9), the anchor bolt (24) being guided in the guide disk (9). Gas injector after Claim 10 , wherein the first damping spring (54) is arranged between the guide disk (9) and the first piston (53) and wherein the second damping spring (64) is arranged between a storage body (17) and the second piston (63). Gas injector according to one of the preceding claims, further comprising: - a first needle guide (31), a second needle guide (32) and a third needle guide (33), which are set up to guide the valve needle (30), - wherein the first needle guide (31) and the second needle guide (32) are arranged in the gas path (14) and the third needle guide (33) is arranged in the lubricant space (4). Gas injector after Claim 12 , wherein a first distance (A1) between the first needle guide (31) and the second needle guide (32) in the axial direction (XX) is smaller than a second distance (A2) between the second needle guide (32) and the third needle guide (33) in Axial direction (XX) is. Gas injector after the Claims 12 or 13 , wherein the first needle guide (31) and / or the second needle guide (32) and / or the third needle guide (33) each have an annular guide area, which is connected to the valve needle (30) via webs in such a way that openings for fluid passage are present between the webs.

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