VALVE AND METHOD FOR THE OPERATION

Abstract

A valve (in particular—a gas valve), a fuel metering unit for a furnace utilizing such valve, and a method for operating the furnace and use of the valve. The valve includes a valve housing and a displaceable piston disposed in the valve housing and configured to be movable with respect to a valve seat of the valve housing in such a manner that two chambers of the valve can be shut off from each other. A piston sealing element for sealing the two chambers is realized between the piston and a piston guide element, the piston sealing element has a diaphragm realizing a sealing element of the piston sealing element.

Claims

1. A fluidic valve comprising: a valve housing and a displaceable piston disposed in the valve housing, the piston being movable with respect to a valve seat of the valve housing in such a manner as to shut off two chambers of the valve from each other, a piston guide element, a piston sealing element realized between the piston and the piston guide element and configured to seal the two chambers wherein the piston sealing element has a diaphragm realizing a sealing element of the piston sealing element.

2. The fluidic valve according to claim 1, wherein the sealing element of the piston sealing element is elastic.

3. The fluidic valve according to claim 1, wherein the sealing element of the piston sealing element is configured to be deformable during a movement of the piston.

4. The fluidic valve according to claim 1, wherein the sealing element of the piston sealing element is dimensioned to be circular-ring-shaped and/or disc-shaped.

5. The fluidic valve according to claim 1, wherein the sealing element of the piston sealing element is clamped and/or positively fixed to the piston and/or to the valve housing.

6. The fluidic valve according to claim 1, wherein the sealing element of the piston sealing element is realized with an inner edge and an outer edge, the inner edge being fixed to the piston (13) and the outer edge being fixed to the valve housing.

7. The fluidic valve according to claim 6, wherein the sealing element of the piston sealing element is realized with beads that are formed on each of the inner edge and the outer edge of the sealing element.

8. The fluidic valve according to claim 1, comprising a line assigned to a chamber of the two chambers, said line connecting two active spaces (31, 32) of the piston permanently, the active spaces being realized in such a manner as to relieve the piston from pressure.

9. The fluidic valve according to claim 1, wherein the valve is realized with a piston stroke of at least 1 mm, or at least 2 mm, or at least 3 mm, or at least 4 mm.

10. The fluidic valve according to claim 1, wherein the valve is realized to be useable for a pressure ≥1 bar, ≥2 bar, or ≥3 bar, or ≥4 bar.

11. The fluidic valve according to claim 1, wherein the valve is realized to be useable for a pressure ≤1 bar, ≤2 bar, ≤3 bar, ≤4 or ≤5 bar.

12. The fluidic valve according to claim 1, wherein the valve is a directly controlled magnetic valve, the piston being actuatable by means of an electromagnet.

13. The fluidic valve according to claim 1, wherein the valve is configured to implement at least 100 switching cycles/minute, or at least 200 switching cycles/minute, or at least 300 switching cycles/minute, or at least 400 switching cycles/minute, or at least 100 switching cycles/minute.

14. The fluidic valve according to claim 1, comprising a valve sealing element realized between the piston and the valve seat, wherein the two chambers are sealed by means of said valve sealing element in a shut-off position, the piston being movable into the shut-off position by means of a spring.

15. A fuel metering unit comprising at least one valve according to claim 1.

16. A furnace at least one fuel metering unit according to claim 15.

17. A method for operating a furnace that contains at least one metering unit including at least one fluidic valve in a valve housing, the method comprising: moving a piston of the at least one fluidic valve with respect to a valve seat to shut off two chambers of the valve from one another, wherein the two chambers are being sealed with a piston sealing element that includes a sealing element of the piston sealing element and that is realized between the piston and a piston guide element, wherein the sealing element of the piston sealing element is realized by a diaphragm of the piston sealing element, and deforming the diaphragm during said moving.

18. The method for operating a furnace according to claim 17, further comprising: metering hydrogen of the at least one metering unit of the furnace.

Description

[0029] Below, a preferred embodiment of the invention is explained in more detail with reference to the accompanying drawings.

[0030] In the figures:

[0031] FIG. 1: shows a longitudinal section view of an embodiment of a valve;

[0032] FIG. 2: shows an enlarged detailed view from FIG. 1.

[0033] A combination of FIGS. 1 and 2 shows a valve 10 having a valve housing 11 and an actuating device 12. Actuating device 12 comprises a piston 13, a sleeve-like piston guide element 14 for the longitudinally movable accommodation of piston 13 and an electromagnetic coil 15 and a holder 16 or magnetic core which accommodates electromagnetic coil 15 and seals valve housing 11 with a flange-like edge 17 and covers electromagnetic coil 15 and has an electrical connection space for energy. Furthermore, an annular slide bush 18 of steel and a sealing bush 19 are provided which at least partially surround holder 16 and/or piston guide element 14 and, thus, coaxially encompass piston 13. In this case, slide bush 18 has no sealing function. Sealing bush 19 closes a magnetic circle (not shown in the case at hand).

[0034] Valve housing 11 realizes a first chamber 20 and a second chamber 21 which have connection threads (not shown in detail in the case at hand) for the connection of media lines (not shown in the case at hand). In the exemplary embodiment, a preferred flow direction of a medium indicated with an arrow 22 from chamber 20 to chamber 21 is provided.

[0035] In valve housing 11, a valve seat 24 is realized coaxially to a longitudinal axis 23 of valve housing 11. Valve seat 24 is closeable by means of a valve sealing element 25. Valve sealing element 25 is formed by a disc 26 having a sealing ring 27 for sealing valve seat 24 and is fixed to piston 13. Furthermore, a through bore 30 realizing a line 29 is provided in piston 13 and on disc 26 and a screw 28 holding disc 26 on piston 13. Through bore 30 which is permeable to media connects a first active space 31 which is assigned to chamber 21 and thus located in chamber 21 to a second active space 32 of piston 13 formed between piston guide element 14 and piston 13. In second active space 32, a spring 33 is disposed coaxially to longitudinal axis 23 between piston 13 and piston guide element 14, said spring causing a return of piston 13 and of the open position (not shown in the case at hand) into a shut-off position of valve 10.

[0036] Since a possible pressure difference between first active space 31 and second active space 32 of piston 13 is essentially always balanced due to through bore 30, first active space 31 is sealed with respect to chamber 20 by means of a piston sealing element 34 disposed in the area of disc 26. This is necessary inasmuch as, in a shut-off position, the same pressure difference exists between chamber 20 and second active space 32 as between chamber 20 and chamber 21. In the partial open position of piston 13, which is shown in the case at hand, electromagnetic coil 15 is supplied with energy which results in a movement of piston 13 along longitudinal axis 23 in the direction of second active space 32 against spring 33. Thus, also disc 26 with sealing ring 27 is lifted off valve seat 24 which allows a flow of a medium from chamber 20 to chamber 21. In this case, piston 13 is moved relative to piston guide element 14.

[0037] Piston sealing element 34 has a diaphragm 35 realizing a sealing element 36. Sealing element 36 consists of rubber and is realized in a circular-ring-shaped manner with an inner edge 37 and an outer edge 38. An essentially circular bead 39 is realized at respective inner edge 37 and outer edge 38. The sealing element is clamped on piston 13 and valve housing 11 and/or on a disc-like ring 40 of valve housing 11 and/or positively connected to them. For this purpose, a clamping ring 41 is screwed on ring 40, clamping ring 41 being realized with a circumferential groove 42 for receiving bead 39. On clamping ring 41, an O-ring 45 in the manner of a stop is disposed which serves to reduce noise and with which disc 26 can come into contact when valve 10 is completely opened. Another clamping ring 43 is provided on piston 13, wherein, in this case, a circumferential groove 44, in which bead 39 on inner edge 37 of sealing element 36 is inserted and clamped there, is realized in piston 13. During a movement of piston 13, sealing element 36 and/or diaphragm 35 is/are now deformed, wherein inner edge 37 and outer edge 38 or respective beads 39 are not deformed as they are firmly fixed. Since diaphragm 35 and/or sealing element 36 can essentially freely deform and are, thus, not subjected to a friction force, wear of the sealing element can be reduced substantially. Furthermore, thereby, also a comparatively larger piston stroke is enabled, which allows a large volume flow to be metered by means of valve 10.