A gas injector with a damping device for particularly short strokes

Abstract

The present invention relates to a gas injector for injecting a gas fuel, comprising a magnetic actuator (2) having an armature (20), an inner magnetic pole (21) and a coil (22), a closure element (3) for opening and closing a gas path (14) at a sealing seat (11), said armature (20) being in operative connection with the closure element (3), a sealed lubricant chamber (4) filled with a lubricant and in which the armature (20) is arranged, the lubricant ensuring lubrication of the armature (20), and a brake mechanism (6) arranged in the lubricant chamber (4), configured to decelerate the closure element (3) during a restoration process of the gas injector from an open state to a closed state, the brake mechanism (6) comprising a brake bolt (60) and a brake mechanism (6) filled with a lubricant and in fluid connection with the lubricant chamber (4) via a first fluid path (101). a damping chamber (62) in which the damping bolt (60) and the elastic damping element (61) can be operatively connected to the armature, a guide disc (25), the damping bolt (60) and the elastic damping element (61) can be operatively connected to the closing element (3) during a restoration process, the damping bolt (60) is configured to displace lubricant from the damping chamber (62) to the lubricant chamber (4) for damping the restoration of the closing element (3) to a closed state during a restoration process of the gas injector, the armature bolt (24) is guided by the guide disc (25), a damping bolt valve (66) is provided at a damping valve seat between the lubricant chamber (4) and the damping chamber (62) for opening and closing the second fluid path (102), and the damping bolt valve (66) is configured to fill the damping chamber (62) with lubricant when the gas injector is in an open state.

Description

Technical Field

[0001] The present invention relates to a gas injector for injecting gaseous fuels, in particular hydrogen or natural gas, etc., for internal combustion engines, which has reduced wear and improved damping behavior. This gas injector is designed in particular for direct injection into the combustion chamber of an internal combustion engine and can very well damp particularly short opening strokes.

Background Art

[0002] From the prior art, gas injectors are known in various configurations. The problem with gas injectors is that, in principle, since the medium to be injected is a gas, lubrication by the medium, which is possible in fuel injectors for injecting, for example, gasoline or diesel fuel, is not possible. This results in excessive wear during operation compared to fuel injectors for liquid fuels. Here, it would be desirable to provide a gas injector with improved wear behavior.

Summary of the Invention

[0003] In contrast, the gas injector for injecting gaseous fuel having the features of claim 1 according to the present invention has the advantage that the wear of the gas injector can be significantly reduced. This can be ensured for both the long opening stroke and the short opening stroke of the gas injector. Thereby, the service life of the gas injector is extended and becomes substantially equivalent to that of a fuel injector for liquid fuel. In particular, by being able to implement a closing process in which the closing element is clearly better damped when the gas injector is closed, wear of the sealing seat and wear of further components of the closing element are reduced or prevented. In particular, when the opening time of the gas injector is short, for example during idling of an internal combustion engine or during several short injection processes, sufficient damping of the closing element returning to the closed position at startup can be ensured. According to the present invention, this is achieved by the gas injector having a lubricant in a sealed lubricant chamber and the movable parts of the gas injector being arranged in the lubricant chamber. The gas injector includes a magnetic actuator having an armature, an inner pole, and a coil. Here, the armature is operatively connected to a closing element that opens and closes the gas path at the sealing seat and is provided to enable movement for opening and / or closing of the gas injector. Thus, the armature in the lubricant chamber, which is pulled towards the inner pole of the magnetic actuator by an electromagnetic force when the coil is energized, is inside the lubricant chamber and is constantly supplied with and lubricated by the lubricant. Thereby, the wear of the armature is significantly reduced compared to gas injectors conventionally known from the prior art. Furthermore, by using a sealed and lubricant-filled lubricant chamber, the service life of the gas injector can be significantly extended. Here, preferably, the lubricant chamber is completely filled with the lubricant.

[0004] The gas injector further includes a braking mechanism disposed within the lubricant chamber, the braking mechanism being configured to decelerate and damp the closing element during the restoration process of the gas injector from an open state to a closed state. The braking mechanism includes a brake bolt, a damping chamber fluidly connected to the lubricant chamber via a first fluid path, and an elastic braking element, in particular a spring. Further, the braking mechanism includes an armature bolt on which the armature is disposed and which is operatively connected to the closing element, and a guide disk on which the armature bolt is guided. The brake bolt valve of the braking mechanism is provided to open and / or close a second fluid path for further filling the damping chamber of the braking mechanism with a filler. Here, the filling of the damping chamber through the second fluid path takes place in the open state of the gas injector. The brake bolt valve is disposed on a brake valve seat between the armature bolt and the brake bolt to open and / or close the second fluid path.

[0005] During the restoration process, the brake bolt and the elastic braking element are operatively connected to the closing element and / or the armature, and the brake bolt is further configured to displace lubricant from the damping chamber in order to damp the restoration of the brake bolt and thus the restoration of the closing element during the restoration process. A part of the deceleration process is also provided by the hydraulic adhesion between the brake bolt and a stopper component against which the brake bolt abuts in the open state of the gas injector. By providing the damping chamber, the vapor lock phenomenon of the liquid lubricant when the hydraulic adhesion is overcome can be prevented, whereby wear due to cavitation in particular can be prevented.

[0006] This is further supported by the acceleration of the additional mass provided by the braking mechanism. Furthermore, additional deceleration is achieved by the displacement of the lubricant by the armature and the brake bolt. By providing two fluid paths for filling the damping chamber with lubricant, reliable and sufficient filling of the damping chamber with lubricant is ensured even when the gas injector is opened for a short time. This can always ensure that there is sufficient lubricant in the damping chamber to damp the restoration process of the closing element during the subsequent closing process of the gas injector. The restoration speed of the closing element can be further reduced by the friction between the guiding element and the brake bolt. All of these can reduce the impact force of the armature on the stopper and further extend the life of the armature.

[0007] The dependent claims indicate preferred developments of the invention. Preferably, the brake bolt valve includes a through-hole in the brake bolt, and the through-hole connects the first end face of the brake bolt and the damping chamber and is part of the second fluid path. The armature bolt has a second end face facing the damping bolt, and in the closed state of the gas injector, the first end face of the brake bolt abuts against the second end face of the armature bolt so that the second fluid path is closed. Therefore, in the closed state, it is impossible for the lubricant to flow into the damping chamber through the through-hole of the brake bolt. Here, the second fluid path opens only in the open state of the gas injector, and sufficient lubricant can reach the damping chamber through the opened brake bolt valve and the through-hole of the brake bolt.

[0008] More preferably, the braking mechanism includes a throttle portion, and the throttle portion is arranged in the first fluid path between the damping chamber and the lubricant chamber. The throttle portion is preferably a stepped hole, which ensures that there is a fluid connection between the damping chamber and the lubricant chamber in any operating state of the gas injector, that is, regardless of whether it is in the open state or the closed state. By selecting the geometric dimensions of the hole, such as the diameter and / or length of the hole, the damping behavior of the braking mechanism can be adjusted.

[0009] The throttle part is preferably arranged inside the guide body, formed as a through-hole of the guide body, and the guide body is configured to guide the brake bolt. Alternatively, the first fluid path is formed between the brake bolt and the guide body, preferably as a groove in the jacket of the brake bolt and / or as a groove in the guide cylinder in the guide body for the brake bolt.

[0010] To ensure that the damping chamber is filled with lubricant as quickly as possible, preferably, one or more channels are formed on the side surface of the guide disk facing the brake bolt. Alternatively or additionally, one or more channels are formed on the first end face of the brake bolt. Here, the additional channels ensure that, in the open state, sufficient lubricant can flow from the lubricant chamber through the second fluid path into the damping chamber. Preferably, when the channels are fluid-connected to each other via circumferential recesses, further improvement of the flow is achieved. The recesses for connecting the channels are preferably formed in the guide disk.

[0011] Preferably, the brake valve seat is formed as a flat sealing seat between the brake bolt and the armature bolt. Alternatively, the brake valve seat is a conical-spherical seat or a conical-conical seat. According to a further preferred configuration of the present invention, the elastic braking element of the braking mechanism is arranged in the damping chamber. Thereby, a particularly compact structure can be realized. The elastic braking element is preferably a compression spring, particularly a cylindrical spring.

[0012] According to a further preferred configuration of the present invention, the gas injector includes a guide body having a guide region for guiding the brake bolt, arranged in the lubricant chamber. The guide body preferably has a recess, particularly at the end facing the sealing seat among the guide bodies for guiding the brake bolt. To ensure the sealing property of the lubricant chamber, preferably, a flexible sealing element, such as a bellows, is provided, and the flexible sealing element seals the lubricant chamber in a partial region.

[0013] Preferably, the flexible sealing element of the lubricant chamber includes first and second flexible sealing elements. Both sealing elements are particularly preferably bellows. Thus, the lubricant chamber is sealed by two flexible sealing elements, thereby preventing the generation of an inconvenient positive or negative pressure during displacement of the lubricant in the lubricant chamber, which inconvenient positive or negative pressure can, for example, exert an unintentional force on the closing element of the gas injector via the components of the lubricant reservoir. By providing two flexible sealing elements, even if an inconvenient force is applied to one of the sealing elements, which can increase the pressure in the sealed lubricant chamber, an equilibrium can be provided by the second flexible sealing element. Thereby, an undesirable pressure change inside the sealed lubricant chamber can be successfully prevented.

[0014] More preferably, the reservoir spring applies a predetermined force from the outside to the lubricant in the sealed lubricant chamber. Here, a positive pressure between preferably 0.5 to 10×10 5 Pa, particularly preferably between 1 to 5×10 5 Pa is applied. Thereby, a predetermined pre-stress can be applied to the lubricant in the lubricant chamber, thereby reliably preventing an undesirable deformation that may affect the stroke of the closing element.

[0015] More preferably, the second bellows is connected to the reservoir spring via a spring receiver. Thereby, a simpler and less expensive structure can be realized. Furthermore, a specific pre-stress can be directly applied to the second bellows by the reservoir spring, whereby the rigidity of the second bellows is slightly higher than that of the first bellows.

[0016] Preferably, as the lubricant, oil, particularly mineral oil is used. As an alternative, liquid fuel, particularly diesel fuel or gasoline is used. As a further alternative, grease or PAO oil (polyalphaolefin) or ester oil or polyglycol oil is used as the lubricant.

[0017] Preferably, the gas injector is an injector that opens outward. More preferably, the gas injector is pressure-balanced. Thereby, the force required to open the gas injector by the magnetic actuator is independent of the gas pressure. Therefore, the time required to open and close the injector after the start and end of current application, respectively, is also independent of the gas pressure. This also enables operation at various gas pressures. The gas pressure can be reduced when it is desired to reduce the injection amount, and the gas pressure can be increased when it is desired to increase the injection amount. The injector is pressure-balanced when the average diameter of the bellows is equal to the diameter of the valve seat contact line between the closing element and the valve body. However, the average diameter of the bellows can be formed smaller or larger than the valve seat diameter. When the average diameter of the bellows is smaller than the valve seat diameter, as the gas pressure increases, the total closing force applied to the valve needle decreases, and the injector opens faster when energized and closes more slowly after energization. Thereby, the gas injection amount increases. When the average diameter of the bellows is larger than the valve seat diameter, as the gas pressure increases, the closing force applied to the valve needle increases. This can also compensate for the increase in the valve seat leakage amount due to the increase in the gas pressure.

[0018] Restoration is preferably performed by a return spring. In the case of a pressure-balanced injector, in particular, in the closed state of the gas injector, there is no compressive force applied to the valve needle by the gaseous fuel, and thus the load on the closing element can be significantly reduced.

[0019] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0021] Hereinafter, with reference to FIGS. 1 to 3, the gas injector 1 according to the first preferred exemplary embodiment of the present invention will be described in detail. As can be seen from FIG. 1, the gas injector 1 for introducing gaseous fuel includes a magnetic actuator 2 that moves a closing element 3, which is a valve needle opening outward in this exemplary embodiment, from a closed state to an open state. Here, FIG. 1 shows the closed state of the gas injector.

[0022] The magnetic actuator 2 includes an armature 20 that abuts against the closing element 3 by an armature bolt 24. The magnetic actuator 2 further includes an inner pole 21, a coil 22, and a magnetic housing 23 that guarantees magnetic feedback of the magnetic actuator.

[0023] Furthermore, the gas injector 1 includes a main body 7 having a connecting pipe 70, and gaseous fuel is supplied through the connecting pipe 70. Here, a valve housing 8 is fixed to the main body 7, and the magnetic actuator 2 is disposed within the valve housing 8. A housing sleeve 19 and a valve pipe 90 are connected to the valve housing 8, and a sealing seat portion 11 is provided at the free end of the valve pipe 90. At the sealing seat portion 11, the closing element 3 releases and closes a passage for gaseous fuel.

[0024] FIG. 1 schematically shows an electrical connection portion 13 that is guided through the main body 7 to the magnetic actuator 2. Reference numeral 10 indicates a restoring element for the closing element 3 to return the closing element 3 to the closed state shown in FIG. 1 after the opening process.

[0025] In FIG. 1, a gas flow is further shown as a gas path 14 through the gas injector 1. Here, the gas flow starts at the connecting pipe 70, then is deflected and enters the annular space 80 between the valve housing 8 and the body 7. Here, the gas flow 14 passes through the outer region of the magnetic actuator 2, through the filter 15, and further proceeds to in front of the sealing seat 11. Here, corresponding openings are provided in the respective components, but not all of them are shown in FIG. 1.

[0026] When the gas injector 1 is open, the gaseous fuel flows into the combustion chamber of the internal combustion engine through the outer circumference of the magnetic actuator 2 and the open sealing seat 11, as indicated by arrow A in FIG. 1.

[0027] Accordingly, the closing element 3 releases and closes the gas path 14 at the sealing seat 11. As can be seen in detail from FIG. 1, for guidance, a first guiding region 31 and a second guiding region 32 are provided between the closing element 3 and the valve body 9. The first guiding region 31 is formed directly between the closing element 3 and the valve body 9 near the sealing seat 11. Here, the second guiding region 32 is formed between the spring receiver 16 and the valve body 9. The spring receiver 16 is fixedly connected to the closing element 3, and the restoring element 10 is supported between the valve body 9 and the spring receiver 16.

[0028] The gas injector 1 further includes a sealed lubricant chamber 4. The sealed lubricant chamber 4 is completely or partially filled with a liquid lubricant, for example, oil. As can be seen from FIG. 1, the lubricant chamber 4 is defined by a first flexible sealing element 51, an inner magnetic pole 21, a magnetic housing 23, a guiding body 18, and a second flexible sealing element 52. The first and second flexible sealing elements 51, 52 are each formed as bellows. Here, the first and second flexible sealing elements 51, 52 are formed in the same way.

[0029] It should be noted that the flexible sealing elements 51, 52 may be, for example, membranes or tubes instead of bellows. As can be further seen from FIG. 1, the second flexible sealing element 52 is fixed to the reservoir spring receiver 41, for example, by a welded joint. The gas injector 1 further includes a reservoir compression spring 40, which is supported by the body 7 and prestresses the second flexible sealing element 52 via the reservoir spring receiver 41. The guide body 18 is provided with a connection hole 18a, whereby the lubricant in the lubricant chamber 4 also exists in the region inside the second flexible sealing element 52.

[0030] The first flexible sealing element 51 is directly fixed to the closing element 3 and is connected to the valve body 9 at the other end. Here, the valve body 9 is provided with a lateral hole 91, whereby a fluid connection exists between the internal space of the first flexible sealing element 51 and the internal space of the valve body 9.

[0031] Thus, the lubricant chamber 4 has two flexible sealing elements 51, 52 and a reservoir compression spring 40. The reservoir compression spring 40 applies a specific prestress, for example, 1×10 5 Pa, to the lubricant in the lubricant chamber 4. Therefore, when displacement of the lubricant occurs due to the stroke of the closing element 3 or further due to thermal expansion or cooling of the lubricant during the opening process, the positive / negative pressure that may occur inside the lubricant chamber 4 can be balanced by the deflection of the second flexible sealing element 52 associated with the contraction of the reservoir compression spring 40. Thereby, the flexible sealing element 51 can be avoided from being affected by an unintended force acting on the closing element 3 via the bellows working surface.

[0032] An armature bolt 24 with an armature 20 fixed thereto is arranged in the sealed lubricant chamber 4. Since the lubricant chamber 4 is filled with a lubricant, such as a liquid fuel like gasoline or diesel fuel, or grease, the armature 20 is continuously lubricated. Thereby, the problem occurring in the prior art in gaseous fuels, namely the lack of lubrication of moving parts, can be compensated for.

[0033] As can be seen from FIG. 1, a filling channel 17a is provided to fill the sealed lubricant chamber 4. The filling channel 17a is liquid-tightly closed by a closing ball 17.

[0034] A braking mechanism 6 is further arranged in the sealed lubricant chamber 4. The braking mechanism 6 includes a brake bolt 60, a damping chamber 62 filled with lubricant, and an elastic braking element 61 formed as a brake spring. The damping chamber 62 is in fluid connection with the lubricant chamber 4. Further, the braking mechanism 6 includes a guide disk 25 through which the armature bolt 24 is guided. Here, the guide disk 25 is provided with a plurality of axially extending openings 25a. Further, the braking mechanism includes a brake bolt valve 66.

[0035] In the open state of the brake bolt valve 66, the armature bolt 24 is moved in the direction of arrow B together with the closing element 3, and the armature bolt does not contact the brake bolt 60. In the closed state of the brake bolt valve 66, the first end face 60a of the brake bolt 60 facing the direction of the armature bolt 24 contacts the second end face 24a of the armature bolt 24. Further, a through hole 67 is also formed in the brake bolt 60, and the through hole 67 connects the first end face 60a to the damping chamber 62.

[0036] FIG. 2 shows the closed state of the gas injector. As can be seen in detail from FIG. 2, there is a permanent connection between the damping chamber 62 and the lubricant chamber 4 via a throttle portion 63. This permanent connection between the damping chamber 62 and the lubricant chamber 4 forms a first fluid path 101, through which lubricant can flow from the lubricant chamber 4 to the damping chamber 62 and vice versa. The first fluid path 101 extends through a guide body 18 in which the throttle portion 63 is formed, as shown in FIG. 2. Here, the throttle portion 63 opens into the connection hole 18a of the guide body 18. The throttle portion 63 can be formed as a stepped straight hole and is located on the central axis of the gas injector.

[0037] In the open state of the gas injector, as can be seen from FIG. 3, a second fluid path 102 is created via the opened brake bolt valve 66. In the open state shown in FIG. 3, the second end face 24a at the end of the armature bolt 24 is lifted from the first end face 60a by the amount of the armature path C. The guide disk 25 is provided with a plurality of radially extending channels 26, which are formed from the openings of the guide disk 25 to the annular recess 27 on the radially inner side of the guide surface for the armature bolt 24. Thus, when the gas injector is open, a second fluid path 102 is created, which is shown by the dashed line in FIG. 3. Thereby, the lubricant can flow through the channels 26 and the recess 27 into the through-hole 67 and from there into the damping chamber 62. Here, the damping bolt 60 is pressed against the guide disk 25 in the axial direction X-X by the elastic braking element 61.

[0038] Therefore, two fluid paths 101, 102 are provided to supply sufficient lubricant to the damping chamber 62 when the gas injector is open. This is particularly important when the opening time of the gas injector is very short, as a rapid restoration of the closing element, and thus also of the armature 20 and the armature bolt 24, has to take place and this restoration has to be sufficiently damped. Such short injection times are given, for example, during idling of an internal combustion engine or during multiple injections.

[0039] Therefore, it is possible to prevent a situation in which no damping occurs by the braking mechanism 6 despite the short opening time of the gas injector. As is apparent from FIG. 3, when the gas injector is opened, the armature bolt 24 is lifted from its seating surface at the braking bolt 60. Thereby, immediately after the lifting, the brake bolt valve 66 is opened and the lubricant can flow through the channels 26, the recess 27 and the through-hole 67 into the damping chamber 62. This flow of the lubricant through the second fluid path 102 is also supported by the elastic braking element 61, ensuring that the braking bolt 60 is pressed against the guide disk 25 in the axial direction and remains in this position. Here, the braking bolt 60 is guided within the guide body 18.

[0040] To fill the damping chamber 62, a flow also occurs through the first fluid path 101 through the always-open throttle part 63. In this exemplary embodiment, a flat sealing seat is formed between the first end face 60a of the brake bolt 60 and the second end face 24a of the armature bolt 24. However, here it is also possible to provide a conical-spherical sealing seat or a conical-conical sealing seat.

[0041] The damping process during the closing of the gas injector is further supported by the brake spring 61 and by the hydraulic adhesion of the brake bolt 60 on the guide disk 25. Here, the damping chamber 62 can prevent cavitation in this region between the guide disk 25 and the first end face 60a of the brake bolt 60 during the closing process of the gas injector.

[0042] By selecting the diameter and / or length of the throttle part 63, the damping behavior can be further individually adjusted for each gas injector. Here, the gas injector 1 shown in FIG. 1 is pressure-balanced. That is, the closing element 3 is connected to the valve body 9 via the first flexible sealing element 51, and the first flexible sealing element 51 formed as a metal bellows has an average diameter equal to the diameter at the sealing seat 11, specifically the diameter at which the closing element 3 seals at the sealing seat 11. Thereby, no compressive force is generated on the closing element 3, and thus the magnetic force required to open the closing element 3 can be kept very small, especially independent of the pressure of the gaseous fuel.

[0043] Therefore, according to the present invention, when the closing element 3 is opened by the operation of the magnetic actuator 2 (movement of the closing element 3 to the left in FIG. 1) and gas injection is carried out, reliable damping can be carried out immediately before the closing element 3 is restored and pressed against the sealing seat portion 11. Thereby, before the closing element hits the sealing seat portion 11, the closing speed of the closing element 3 is significantly and effectively decelerated. Thereby, wear of the sealing seat portion 11 and the closing element 3 can be effectively reduced, and here the braking mechanism 6 further enables a quieter operation of the gas injector. So-called closing collisions where the element hits the sealing seat portion violently and rebounds while colliding can also be effectively prevented.

[0044] Therefore, the gas injector 1 can reduce wear of movable parts, in particular the sealing seat portion 11, the armature 20, and the armature bolts 24, and can ensure sufficient damping by the damping chamber 62 that is always sufficiently filled through both fluid paths 101, 102 even in the case of a small stroke. Furthermore, heat dissipation from the magnetic actuator 2 can be significantly improved by the sealed lubricant chamber 4 containing a liquid lubricant. Furthermore, both flexible sealing elements 51, 52 can prevent an unintentional force from acting on the closing element 3.

[0045] FIG. 4 shows an enlarged partial cross-sectional view of the braking mechanism of the gas injector according to a second preferred exemplary embodiment of the present invention. Identical or functionally identical parts are labeled with the same reference numerals as in the first exemplary embodiment.

[0046] FIG. 4 shows the closed state of the gas injector, similar to FIG. 2 of the first exemplary embodiment. Here, in the second exemplary embodiment, the first fluid path 101 is not formed as a throttle portion of the guide body 18, and the fluid connection between the damping chamber 62 and the lubricant chamber 4 is formed between the brake bolt 62 and the cylindrical accommodation space of the guide body 18 for the brake bolt 62. As shown in FIG. 4, here, in the jacket region of the brake bolt 60, one or more grooves 60a are formed in the brake bolt 60. Alternatively, the first fluid path 101 can also be adjusted by the play between the brake bolt 60 and the cylindrical region of the guide body 18 in which the brake bolt 60 is received. Further alternatively or additionally, one or more grooves can be provided in the cylindrical region of the guide body 18. Thus, a throttle occurs in the first fluid path in the region between the brake bolt 60 and the cylindrical partial region of the guide body 18. Otherwise, this exemplary embodiment is the same as the previous exemplary embodiment, and reference can be made to the description given there.

Claims

1. - A magnetic actuator (2) having an armature (20), an inner pole (21), and a coil (22); - A closing element (3) for opening and closing a gas path (14) at a sealing seat (11), wherein the armature (20) is operatively connected to the closing element (3); - A sealed lubricant chamber (4) filled with a lubricant and having the armature (20) disposed therein, the lubricant ensuring lubrication of the armature (20); - A braking mechanism (6) disposed within the lubricant chamber (4), configured to decelerate the closing element (3) during a restoration process of a gas injector from an open state to a closed state, a gas injector for injecting gaseous fuel, comprising: - The braking mechanism (6) includes a brake bolt (60), a damping chamber (62) filled with a lubricant and fluid-connected to the lubricant chamber (4) via a first fluid path (101), an elastic braking element (61), an armature bolt operatively connected to the armature, and a guide disk (25), wherein the brake bolt (60) and the elastic braking element (61) can be operatively connected to the closing element (3) during a restoration process, and the brake bolt (60) is configured to displace the lubricant from the damping chamber (62) to the lubricant chamber (4) to attenuate the restoration of the closing element (3) to the closed state during the restoration process of the gas injector, the armature bolt (24) is guided by the guide disk (25), and a brake bolt valve (66) is provided for opening and closing a second fluid path (102) at a brake valve seat between the lubricant chamber (4) and the damping chamber (62), and the brake bolt valve (66) is configured to fill the damping chamber (62) with lubricant when the gas injector is in an open state; A gas injector.

2. A through hole (67) is formed in the brake bolt (60), the through hole (67) connects the first end face (60a) of the brake bolt (60) to the damping chamber (62), the armature bolt (24) has a second end face (24a), and in the closed state of the gas injector, the first end face (60a) of the brake bolt (60) abuts against the second end face (24a) of the armature bolt (24), and the second fluid path (102) is closed, so that lubricant may not flow into the damping chamber (62) through the through hole (67). The gas injector according to claim 1.

3. The braking mechanism (6) further includes a throttle portion (63), and the throttle portion (63) is disposed between the damping chamber (62) and the lubricant chamber (4) within the first fluid path (101). The gas injector according to claim 1.

4. The throttle portion (63) is configured to be open regardless of whether the gas injector is in an open state or a closed state, and is formed as a stepped hole. The gas injector according to claim 3.

5. A plurality of channels are formed on a side surface of the guide disk (25) facing the brake bolt (60). The gas injector according to claim 1.

6. The plurality of channels are fluidly connected to each other by recesses (27). The gas injector according to claim 5.

7. The recess (27) is formed in the guide disk (25). The gas injector according to claim 6.

8. The brake valve seat of the brake bolt valve (66) is formed as a flat sealing seat portion, or a conical-spherical seat portion, or a conical-conical seat portion. The gas injector according to claim 1.

9. The elastic braking element (61) is disposed within the damping chamber (62). The gas injector according to claim 1.

10. It further includes a guide body (18) disposed within the lubricant chamber (4), and the guide body (18) is configured for guiding the brake bolt (60). The gas injector according to claim 1.

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