CN105888887B

CN105888887B - Gas valve with improved sealing properties

Info

Publication number: CN105888887B
Application number: CN201610084560.9A
Authority: CN
Inventors: J·拜尔; R·林德纳
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2015-02-12
Filing date: 2016-02-14
Publication date: 2020-07-28
Anticipated expiration: 2036-02-14
Also published as: CN105888887A; DE102015202477A1

Abstract

The invention relates to a gas valve for controlling a gaseous medium, comprising: a movable valve closing element (2) for releasing and closing the at least one through opening (3); a sealing seat (4) between the stationary valve member (5) and the valve closing element (2); an elastomeric seal (6); a seal carrier (7) on which the elastomer seal (6) is arranged, wherein the seal carrier (7) is connected to the valve closing element (2); and a separate adjusting element (8) which is arranged on the seal carrier (7) and which is provided as a stop in the valve closed state and which defines a projection of the elastomer seal (6) in the axial direction (X-X) beyond a stop surface (82) of the adjusting element (8) in the valve open state.

Description

Gas valve with improved sealing properties

Technical Field

The invention relates to a gas valve with an adjusting element and an elastomer seal in order to provide an improved tightness of the gas valve in the closed state.

Background

Gas valves are known from the prior art in various embodiments. In the automotive field, gaseous fuels, such as natural gas or hydrogen, are increasingly used in recent times in addition to liquid fuels. Frequently, injection valves for liquid fuels are known here simply and invariably for gaseous media. However, valves for liquid media often do not meet the specific requirements for gaseous media. For sealing gaseous media, in particular elastomeric seals are particularly suitable. Such elastomeric seals are typically manufactured by means of an injection molding process. In this case, however, relatively large tolerances (in particular in the opening and closing direction of the valve) are produced in connection with the production. This, however, leads to an undesirably large deviation in the sealing properties of the gas valve, which leads to a very high specific gravity of waste in production. DE 102007006934 a1 discloses a gas valve designed in particular for gaseous media, which has in particular an improved cold start capability. For this purpose, a stop is provided which is formed in one piece with the magnetic armature. As a result, however, manufacturing-related dimensional deviations of the elastomer seal cannot be calibrated.

Disclosure of Invention

In contrast, the valve for controlling a gaseous medium according to the invention having the features of claim 1 has the advantage that even if the elastomer seal has manufacturing-related tolerances, in the open state of the valve the amount of protrusion of the elastomer beyond the stop surface is constant and the valve can be reliably closed. A reliable sealing can be achieved here by means of an elastomer seal. This is achieved according to the invention by: the elastomer seal is arranged on a seal carrier which is connected to the movable valve closing element for the release and closing of the through-opening. According to the invention, a separate adjusting element is provided, which is arranged on the seal carrier and acts as a stop in the closed valve state. A predetermined projection of the elastomer seal in the axial direction can be defined by the separate adjusting element, and the tolerance-related deviations of the elastomer seal are therefore calibrated by the separate adjusting element, so that there is a constant projection of the elastomer seal beyond the adjusting element. Thus, all valves have the same amount of protrusion of the elastic body and thus also the same opening and closing performance. The invention thus makes it possible to significantly improve the production process and in particular also to adjust tolerances occurring in the production of the elastomer seal by means of the adjustable adjusting element.

The dependent claims present preferred developments of the invention.

Preferably, the discrete adjustment element is an adjustment ring. This makes it possible to fix the adjusting ring to the seal carrier in a simple and reliable manner. Furthermore, the discrete adjustment element can be easily adjusted in order to define the amount of protrusion of the elastomeric seal.

In order to set the projection of the elastomer seal particularly quickly and easily, a first press-fit connection is preferably formed between the adjusting ring and the seal carrier.

Furthermore, a welded connection is preferably provided between the adjusting ring and the seal carrier. By fixing the adjusting ring by means of the welded connection, the adjusted relative position of the adjusting ring with respect to the seal carrier can thus be reliably fixed.

According to a further preferred embodiment of the invention, the adjusting ring has an inwardly directed region which rests on an outer edge region of the elastomer seal or also permits an assembly gap, and wherein in particular the inwardly directed region provides a surround. The inwardly directed region serves as a flat stop which protects the elastomeric seal from overload and damage. A radial assembly gap may also be provided between the elastomer seal and the stop ring.

Preferably, the adjusting element is stopped on a stationary valve member having a through-opening which is opened and closed by means of a valve closing element.

Preferably, the seal carrier has an outer cylindrical circumferential surface region and an inner inwardly projecting retaining region. The adjusting ring is arranged here on an outer circumferential surface region, and the elastomer seal is arranged on an inwardly projecting holding region. This makes it possible to reliably fix the elastomer seal on the one hand and to easily adjust the adjusting ring on the outer circumferential surface region of the seal carrier on the other hand.

More preferably a stationary valve member with a through opening and a sealing washer. The through-openings are preferably kidney-shaped and more preferably arranged uniformly spaced apart from one another in the circumferential direction.

The valve closing element is preferably a magnetic armature, on which the seal carrier is arranged.

Particularly preferably, a second press-fit connection is formed between the valve closing element and the magnetic armature. Additionally or alternatively, a welded connection can also be provided.

Preferably, the sealing seat is designed as a flat-bottomed sealing seat (flachdichtstitz). The sealing element preferably has a C-shaped cross section and at least partially surrounds the seal carrier.

The invention further relates to an internal combustion engine comprising a valve according to the invention. The valve according to the invention is particularly preferably designed as a metering valve for metering a predetermined quantity of gaseous fuel.

Drawings

Preferred embodiments of the present invention are explained in more detail below with reference to the accompanying drawings. In the drawings, identical or functionally identical components are denoted by the same reference numerals. In the drawings:

FIG. 1: a schematic cross-sectional view of a valve according to a first embodiment of the invention in a closed state;

FIG. 2: a schematic cross-sectional view of a valve according to a second embodiment of the invention in a closed state;

FIG. 3: a schematic cross-sectional view of a valve according to a third embodiment of the invention in a closed state; and

FIG. 4: schematic cross-sectional view of a valve according to a fourth embodiment of the invention in closed state.

Detailed Description

A valve 1 according to a first embodiment of the invention is described in detail below with reference to fig. 1.

As is apparent from fig. 1, the valve 1 comprises a movable valve closing element 2, the valve closing element 2 being a magnetic armature in this embodiment. The valve closing element 2 is designed as a hollow cylinder, so that the gaseous fuel can be conducted both inside and outside the valve closing element 2.

The valve closing element 2 is arranged in a valve body 10, which valve body 10 is closed by a sealing gasket 5 providing a valve seat. The valve body 10 is a hollow cylindrical component and seals the sealing gasket 5 on the free end of the valve body 10. In the sealing washer 5, a plurality of kidney-shaped through-openings 3 are provided, which through-openings 3 are released and closed by means of the valve closing element 2. Fig. 1 shows the closed state of the valve.

In order to achieve a reliable seal for the gaseous medium, an elastomer seal 6 is provided according to the invention. An elastomer seal 6 is arranged on the valve closing element 2 via a seal carrier 7. The seal carrier 7 is a substantially annular component having an outer cylindrical circumferential surface region 70 and an inner holding region 71 for holding the elastomer seal 6. The cylindrical circumferential surface region 70 of the seal carrier 7 serves for fastening the adjusting element 8.

The elastomer seal 6 has a C-shaped cross-section that snaps onto an inner retaining area 71 of the seal carrier 7. The elastomer seal 6 can be directly injection-molded onto the seal carrier 7, for example by means of an injection molding method. The snapping (encircling) of the elastomer improves the adhesion on the seal carrier.

As is apparent from fig. 1, the elastomer seal 6 is located on the through-opening 3 in the closed valve state and seals the through-opening on the seal seat 4. The sealing seat 4 comprises exactly two

annular sealing zones

40, 41, one of which is arranged radially inside and one of which is arranged radially outside the through-opening 3.

Furthermore, the valve according to the invention comprises an adjusting element 8, the adjusting element 8 being an adjusting ring in this embodiment. The adjusting element 8 comprises a sleeve region 80 and an inwardly directed region 81. The sleeve region 80 serves to fix the adjusting element 8 to the seal carrier 7. The inwardly directed region 81 serves as a stop surface and thus protects the elastomer seal against wear due to excessive face pressure and serves to radially support the elastomer seal 6 on the outer edge region 60. A press-fit connection 9 is formed between the adjusting element 8 and the seal carrier 7.

According to the invention, the annular adjusting element 8 can now be assembled after the injection molding of the elastomer seal 6 on the seal carrier 7. The position of the adjusting element 8 in the axial direction X-X relative to the seal carrier 7 can be changed on the basis of the press-fit connection 9 between the adjusting element 8 and the seal carrier 7. The position of the adjusting element 8 can be selected such that the amount of protrusion of the elastomer seal 6 beyond the stop surface 82 is always constant at the adjusting element 8. The different thicknesses of the elastomer seal 6 that may occur due to the injection molding process can thus be calibrated by correspondingly positioning the adjusting element 8 on the seal carrier 7. The elastomer projection with which the elastomer seal 6 projects in the axial direction X-X beyond the stop face 82 can thus be adjusted individually to a constant extent. The specific gravity of the waste of the valve provided with the elastomer seal can thereby be significantly reduced.

In order to fix the relative position of the adjusting element 8 on the seal carrier 7, a first welded connection 11 is also provided.

More preferably, a second welded connection 12 is formed for fixing the seal carrier 7 on the valve closing element 2. The two welded

connections

11, 12 can be realized in one working step.

According to the invention, the manufacturing-related thickness differences of the elastomer seal can thus be calibrated by means of a movable adjusting ring (with a clearance fit or press fit) on the seal carrier 7. For this purpose, according to the invention, the elastomer seal 6 is first applied to the seal carrier 7 and the elastomer projection is subsequently measured (for example in the axial direction X-X starting from the end face of the seal carrier 7). Next, the adjusting ring is applied to the seal carrier 7 and the elastomer projection is measured starting from the stop face 82 of the adjusting ring. Corrections can then also be made if possible. Due to the press-fit connection 9 between the adjusting ring and the seal carrier 7, no forced welding is necessary. In order to securely fix the adjusting ring on the seal carrier 7, however, a first weld seam 11 can be formed.

Fig. 2 shows a valve 1 according to a second embodiment of the invention. In contrast to the first exemplary embodiment, in the second exemplary embodiment, no press-fit connection or clearance fit is provided between the adjusting element 8 and the seal carrier 7, but only the first welded connection 11. A particularly simple adjustment of the adjusting element 8 relative to the seal carrier 7 in the axial direction X-X can thereby be achieved, since no press fit has to be overcome.

Fig. 3 shows a valve 1 according to a third embodiment of the invention. In contrast to the first exemplary embodiment, in the third exemplary embodiment, the adjusting element 8 is connected to the seal carrier 7 only by means of a press-fit connection 9. In this case, no welded connection is provided between the adjusting element 8 and the seal carrier 7. In this embodiment, therefore, the welded connection between the adjusting element 8 and the seal carrier 7 can be dispensed with. Furthermore, in the third embodiment, a second press-fit connection 13 between the seal carrier 7 and the valve closing element 2 is also provided. The third exemplary embodiment is therefore completely adequate without a weld seam, so that the production can be significantly simplified.

Fig. 4 shows a valve 1 according to a fourth exemplary embodiment of the invention, which corresponds essentially to the first exemplary embodiment, wherein the welded connections are designed differently, in the fourth exemplary embodiment the first and second welded

connections

11, 12 are designed as radial welded connections (Radialschwei β verindung), in the first exemplary embodiment the second welded connection is designed as a blunt welded connection (stmpfe Schwei β verindung), which corresponds to the preceding exemplary embodiment, so that the description given there can be omitted.

Claims

1. A gas valve for controlling a gaseous medium, comprising:

-a movable valve closing element (2) for releasing and closing the at least one through opening (3);

-a sealing seat (4) between a stationary valve member (5) and the valve closing element (2);

-an elastomeric seal (6);

-a seal carrier (7) on which the elastomer seal (6) is arranged, wherein the seal carrier (7) is connected with the valve closing element (2); and

-a separate adjusting element (8) which is provided on the seal carrier (7), which adjusting element is provided as a stop in the valve-closed state and which, in the valve-open state, defines a projection of the elastomer seal (6) in the axial direction (X-X) beyond a stop surface (82) of the adjusting element (8),

characterized in that the adjusting element (8) has an inwardly directed region (81) which rests on the outer edge region (60) of the elastomer seal (6) or which also permits assembly play.

2. Valve according to claim 1, characterized in that the adjusting element (8) is an adjusting ring.

3. Valve according to one of the preceding claims, characterized in that a first press-fit connection (9) is formed between the adjusting element (8) and the seal carrier (7).

4. Valve according to claim 1 or 2, characterized in that a first welded connection (11) is formed between the adjusting element (8) and the seal carrier (7).

5. A valve according to claim 1 or 2, wherein the inwardly directed region (81) provides a surround.

6. A valve according to claim 1 or 2, wherein the adjusting element (8) in the valve closed state stops against the stationary valve member (5).

7. Valve according to claim 1 or 2, wherein the seal carrier (7) has an outer cylindrical circumferential surface region (70) and an inner retaining region (71), wherein the adjusting element (8) is arranged on the circumferential surface region (70) and the elastomer seal (6) is arranged on the retaining region (71).

8. A valve according to claim 1 or 2, wherein the stationary valve member (5) is a sealing gasket.

9. A valve according to claim 1 or 2, characterized in that the valve closing element (2) is a magnetic armature.

10. Valve according to claim 1 or 2, wherein the sealing seat (4) is a flat-bottomed sealing seat.

11. An internal combustion engine comprising a valve according to any preceding claim.