AU2003204219A1

AU2003204219A1 - Magnetic valve

Info

Publication number: AU2003204219A1
Application number: AU2003204219A
Authority: AU
Original assignee: Carl Freudenberg KG
Current assignee: Carl Freudenberg KG
Priority date: 2002-05-16
Filing date: 2003-05-15
Publication date: 2003-12-04
Also published as: CA2428773A1; EP1363055A2; DE10222218A1; KR20030089444A; MXPA03004210A; EP1363055A3

Description

Our Ref:7814423 P/00/011 Regulation 3:2

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): Carl Freudenberg KG 69469 Weinheim Germany Address for Service: Invention Title: DAVIES COLLISON CAVE Patent Trade Mark Attorneys Level 10, 10 Barrack Street SYDNEY NSW 2000 Magnetic valve The following statement is a full description of this invention, including the best method of performing it known to me:- 5020 02PA0005/DE 25.04.2002 Da/ic Applicant: Carl Freudenberg, 69469 Weinheim, DE Title MagneticValve Description The present invention relates to a magnetic valve for the front face sealing of a valve seat positioned in the lift direction of the magnet armature and sealing element, in particular a regeneration valve for a tank venting line in motor vehicles.

The use of electromagnetic metering valves is generally known. In such valves the throughput flow rate in both regions can be controlled by variation of the pulse-pause ratio of the electric drive control. For this purpose, the magnet armature which performs an oscillating motion when in operation, is pressed onto the valve seat at variable time intervals, or is lifted from the valve seat depending on the desired throughput flow rate. At the front face, the magnet armature is provided with a valve seat elastomer. These valves are as a rule required to be resistant to aggressive media and to maintain their metering precision even in a wide temperature range. Furthermore they are required not to be acoustically perceptible, if possible, and to be manufactured at the lowest possible cost. Predominantly, in such situations, magnetic valves are employed which permit a rapid movement of the sealing element and whose drive control frequency is at least 10 Hz. A particular problem experienced with these magnetic valves is the positioning and mounting of the magnet armature which reaches very high timing pulse rates in operation but all the same is expected to have a long life.

2 State of the Art DE 42 29 110 C 1 shows a regeneration valve wherein the sealing element is actuated by an electrically driven magnetic coil. These regeneration valves have proven to be successful in practical applications.

Summary of the invention It is the object of the present invention to propose an improved positioning and mounting of the magnet armature in order to obtain a characteristic curve band having a narrow range of tolerance even after long operating periods of the valve. A further object of the invention is to reduce large throughputs of fuel vapour thereby leading to an improved magnetic force-path characteristic curve. A further object is to improve the micro-dosing performance.

The present invention provides the solution to the aforementioned needs with the characteristics of Claim 1. In a magnetic valve of the type mentioned at the outset, the magnet armature with the sealing element fastened thereto is held by two flat springs hinged to the valve box. This measure permits a frictionless positioning and mounting of the magnet armature. Friction forces which otherwise occur in customary seatings of the magnet armature in an armature hub or also in core panels are avoided by the proposed solution. This results in a particularly favourable force-path characteristic curve for the magnetic force to be applied. A side tilt of the magnet armature is prevented by virtue of the flat springs arranged at both sides of the magnet armature.

Any wear in any particular seating of the magnet armature is prevented and a good long term behaviour during its entire life is achieved. Preferably, the flat springs are designed as meander springs.

To achieve weight saving, the magnet armature can be designed in the shape of a cylinder. The sealing element is arranged at the end of the magnet armature directed towards the valve seat. In this way it covers the inner bore of the armature.

A large throughput of fuel vapour is facilitated when the magnet armature concentrically embraces the pole body with its upper edge. In this way a larger throughput is achieved. A particularly favourable embodiment of the valve is achieved by virtue of the magnet armature being coaxially surrounded by the pole plate. The pole plate is connected with the housing of the magnetic valve and the meander springs can be attached to both sides of the pole plate. For this purpose, the pole plate is provided with spacing nipples at both sides to which the meander springs are attached. The meander springs can be caulked or welded to these spacing nipples. For easier production and in order to facilitate mounting of the guide element at the valve box, the guide element can be arranged in reverse symmetry with the meander springs, i.e. so that the guide element can be connected with the meander springs with the valve box in any event, no matter on which side the guide element is inserted into the box.

It is advantageous if the sealing element consists of a metallic support body provided with openings and an elastomeric sealing facing which is connected with the support body by way of a formfit and/or a press fit. In this way a very secure connection can be made between the sealing facing and the support body. Moreover the support body facilitates the connection of the sealing element with the magnet armature. Towards this end, the magnet armature is provided with a circumferential recess at its edge directed towards the valve seat into which recess the support body is pressed.

The design of the magnet armature with sealing element and flat springs can be used particularly advantageously in a regeneration valve where the valve box at its centre has a laval nozzle whose nozzle tip forms the valve seat.

Brief description of the drawing The invention is described in greater detail below by reference to an embodiment example shown in the drawing.

Shown are in: Fig. 1 the magnetic valve in longitudinal section.

Fig. 2 a view of the magnet armature with flat spring and pole plate Fig. 3 a side view of the magnet armature with flat springs and pole plate and Fig. 4 a section through magnet armature, flat springs and pole plate according to line C-C in Fig. 2.

Embodiments of the invention Fig. 1 shows a section of a magnetic valve 1, which facilitates a high drive control frequency. The box of the magnetic valve 1 consists of an upper part 2 and a lower part 3. Into the upper part 2 there is inserted an electromagnet 4 with the pole body 12. The latter interacts with the magnet armature 5 which is provided with the sealing element 6.

By means of the spring 7, arranged at the centre of the electromagnet, the sealing element 6 is pressed onto the valve seat 8 which is situated in the lower box part 3. A design without spring 7 wherein only the flat springs 9 and 10 press the sealing element 6 onto the valve seat 8 is possible and its use is advantageous in some applications. The magnet armature 5 is held in position by the flat springs 9 and 10, which are designed as meander springs. At the magnetic return path pieces 11 of the electromagnet 4 there is arranged the pole plate 13, which at the same time serves as accommodation for the magnet armature 5. There is however no contact between the magnet armature 5 and the pole plate 13. The pole plate 13 is provided at its top side and at its bottom side with spacing nipples 14 and 15 at which the meander springs 9 and 10 are fastened.

The two box parts, upper part 2 and lower part 3 are connected. Into the middle of the lower box part 3 there is inserted the Laval nozzle 16, the nozzle tip of which forms the valve seat 8. The medium flowing through the valve enters into the annular chamber 17 of the lower valve part 3 and flows to the outside via the Laval nozzle 16.

Fig. 2 shows a view of the pole plate 13 with the meander spring 10 attached thereto and of the magnet armature 5 held by the meander spring 10. The underside of the sealing element 6 is visible. The pole plate 13 is provided with two straps 19 and 20 in opposite position with which it is attached at the magnetic return path pieces 11.

Openings 21 are provided for this purpose into which corresponding pins of the magnetic return path pieces 11 are inserted. The meander spring 10 is provided with three spring legs 22. With their interior edge 23 it is welded or caulked to the magnet armature 5. At the connection points 24 for the spring legs 22, the meander spring 10 is also connected with the nipples 14. The nipples 15 positioned below the pole plate 13 are shown as dashed lines. The meander spring 9 positioned below the pole plate 13 is caulked onto these nipples 15. The nipples 15 are situated in reverse symmetry to the nipples 14, i.e. the pole plate 13 can be used from the one side as well as from the other.

Fig. 3 shows a lateral view of the pole plate 13 with the meander springs 9 and 10 and the magnet armature 5 with sealing element 6. The three spacing nipples 14 and two of the spacing nipples 15 situated on the opposite side are visible.

Fig. 4 shows a section through Fig. 2 along line C-C. The magnet armature 5 is held at the pole plate 13 by the meander springs 9 and 10. For this purpose, the pole plate 13 is equipped with nipples 14 and 15. As is visible on the lower part of this figure, the nipples 14 and 15 are produced by embossings on the pole plate 13. The sealing element 6 is inserted into the cylindrical magnet armature 5. The sealing element 6 consists of the metallic support body 30 which is provided with a perforation and of the elastomeric sealing facing 31 and opening limit stop 32 present on both sides of the support body The spring 7 is positioned on to the nipples 18. When the sealing facing 31 and the opening limit stop 32 are installed, the elastomer, during the vulcanization process, flows through the perforation present in the support body 30, so that a conjugate connection is produced between the support body 30 and the elastomeric sealing facing 31 or the opening limit stop 32. The edge 33 of the support body 30 is inserted into a circumferential recess 34 at the magnet armature 5 and in this way the sealing element 6 is connected with the magnet armature 5. The edge 35 of the magnet armature directed towards the pole body is on its inner surface 36 of a conical design and embraces the lower edge of the pole body 12 which is also conical. By virtue of this design and arrangement of magnet armature 5 and pole body 12 a mass throughput is possible when valve 1 is open.

Throughout this specification and the claims which follow, unless the context requires otherwise the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

The reference to any prior art in this specification is not, and should not be taken as an acknowledgment or any form of suggestion that, that prior art forms part of the common general knowledge in Australia.

Claims

1. A magnetic valve for the front face sealing of a valve seat positioned in the lift direction of the magnet armature and sealing element, in particular a regeneration valve for a tank venting line in motor vehicles, characterised in that the magnet armature with the sealing element fastened thereto is held by two flat springs 10) hinged to the valve box

2. A magnetic valve according to claim 1, characterised in that the flat springs (9, are designed as meander springs.

3. A magnetic valve according to claim 1 or 2 characterised in that the magnet armature is designed in the shape of a cylinder.

4. A magnetic valve according to any one of claims 1 to 3, characterised in that the magnet armature concentrically embraces the pole body (12) with its upper edge

5. A magnetic valve according to any one of claims 1 to 4, characterised in that the magnet armature is coaxially surrounded by the pole plate (13).

6. A magnetic valve according to any one of Claims 1 to 5, characterised in that the pole plate (13) is provided with spacing nipples (14, 15) at both sides to which the meander springs 10) are attached.

7. A magnetic valve according to any one of Claims 1 to 6, characterised in that the meander springs 10) are caulked or welded to these spacing nipples (14,

8. A magnetic valve according to any one of Claims 1 to 7, characterised in that the pole plate (13) is arranged in reverse symmetry with the meander springs

9. A magnetic valve according to any one of Claims 1 to 8, characterised in that the sealing element is connected with the magnet armature A magnetic valve according to any one of Claims 1 to 9, characterised in that the sealing element consists of a metallic support body (30) provided with openings and an elastomeric sealing facing (31) or limit stop (32) which is connected with the support body by way of a formfit and/or a press fit.

11. A magnetic valve according to any one of Claims 1 to 10, characterised in that the sealing element is arranged at the end of the magnet armature directed towards the valve seat

12. A magnetic valve according to any one of Claims 1 to 11, characterised in that the lower box part has at its centre a Laval nozzle whose nozzle tip forms the valve seat DATED this 1 4 th day of May, 2003 CARL FREUDENBERG KG By Their Patent Attorneys DAVIES COLLISON CAVE