Valve

Abstract

Valve for gaseous and liquid media, having the following features: a) a valve body (2) with a valve chamber (14), a valve seat (13) provided therein, a sealing element (22) that can be pressed against the latter, at least one inlet (11) and at least one outlet (12) for the medium, b) a magnetic head (1) with a housing (4), an electric coil (5) and a magnetic core (6), c) a plate anchor (23) axially displaceable with an anchor disk (24), to which a disc spring (26) is assigned, characterized in that d) that an anchor chamber (15) is formed above the valve body (2) in which the plate anchor (23) with the anchor disk (24) and the disc spring (26) are mounted, e) that the anchor space (15) is associated with a vent hole (10), f) that the valve chamber (14) and the anchor chamber (15) are hermetically separated by a bellows (16), g) that the armature space (15) is bounded by the bellows (16), the electric coil (5), the magnetic core (6) and at the circumference by the wall (7) of the housing (4), h) that a flange part (20) of the bellows (16) is fixed to the wall (7) of the housing (4) of the magnetic head (1) with a circumferential edge region (21), i) that the disc spring (26) is arranged in a plane between the anchor disk (24) and the flange part (20) of the bellows (16).

Description

[0001] The invention relates to a valve having the features of the preamble of claim 1.

[0002] DE 44 19 446 A1 discloses a valve of this type, wherein the valve body has a valve seat protruding into a valve chamber, which is mounted in a valve body base wall for axially continuously adjustable movement. An axially displaceable plate armature is arranged in the valve chamber, which has an armature disk, a thin disc spring positioned on the underside of the disk, and a sealing body corresponding to the valve seat. The valve chamber is delimited on the side opposite the valve body base wall by an electric coil and a magnetic core of a magnetic head, wherein the front end of the electric coil is slightly recessed from that of the magnetic core. The disc spring is fixed with its peripheral edge to a shoulder of a valve body wall by the front end of a magnetic head wall. The magnetic core is also axially continuously adjustable within the magnetic head wall via a thread.When the valve seat is open, the armature disc and the disc spring in the valve chamber are flushed with the medium supplied through an inlet, which is discharged from the valve chamber through an outlet.

[0003] WO 97 / 15 771 A1 discloses a solenoid valve comprising a solenoid head and a valve body having a valve seat formed in a valve chamber and an inlet and an outlet for the medium. A relatively long, cylindrical solenoid plunger is slidably mounted in the axial bore of an electric coil body within the solenoid head. A helical compression spring is located in an axial blind bore in the upper portion of the solenoid plunger, which is enclosed by the electric coil. A lower, tapered end portion of the solenoid plunger engages a bellows convoluted portion, which is pressed by a flange portion against a base plate defining the bottom of the solenoid head housing. The helical compression spring presses the solenoid plunger downward against the valve seat, which is locked by the lower end of the bellows convoluted portion.

[0004] DE 198 54 759 A1 also discloses a solenoid valve comprising an electromagnetic head and a valve body with a valve chamber, a valve seat, and an inlet and outlet for a medium. An elongated solenoid pin is axially displaceably mounted in a central hole of a coil body carrying an electric coil. The lower end of the solenoid pin has a reduced diameter and is located in a bellows, which is arranged with a flanged circumference in a plane between the valve body and the coil body. In the upper part of the solenoid pin, a blind hole extending almost to its longitudinal center is formed, in which a helical spring displacing the solenoid pin and a stop pin are mounted. The helical spring presses the solenoid pin toward the valve seat.

[0005] DE 198 51 143 A1 discloses a proven valve in which a disc-shaped spring is embedded in and encased in an elastomer jacket designed as a sealing plate. This sealing plate with the integrated spring is essentially flat and represents a hermetic separation between an armature chamber containing a plate armature and a valve chamber in which a valve seat is provided. The flat sealing disc is a flat diaphragm that is clamped at its circumference and is axially displaceable in its central region according to the plate armature stroke. The pressure of the medium in the valve chamber acts against the relatively large total surface area of ​​the sealing disc. Accordingly, relatively large actuating forces are inevitably required to overcome the medium pressure, whereby the disc spring must be correspondingly highly preloaded.Overall, this may impair the safety, switching function and service life of the valve.

[0006] DE 30 15 522 A1 discloses a solenoid valve comprising a valve body, a magnetic head, and an axially displaceable plate armature, which may be enclosed by a plastic membrane arranged with its peripheral edge on the valve housing. The plate armature is subjected to the force of an axial coil spring acting in the direction of a valve seat. The spring is mounted in the magnetic head, which may also have a vent hole.

[0007] The object of the invention is to further develop a valve of the type described at the outset in such a way that a high degree of reliability of media separation, fast and smooth valve switching and long-term functionality of the valve are achieved using simple means.

[0008] This object is achieved according to the invention by the features of claim 1.

[0009] Appropriate embodiments and further developments of the invention are characterized by the features of the subclaims.

[0010] Further advantages and essential details of the invention can be found in the following description and the drawing, which shows a preferred embodiment as an example in a single figure in schematic representation.

[0011] The drawing shows an enlarged sectional view of a valve according to the invention. The valve is designed for gaseous and liquid media and comprises a magnetic head 1 and a valve body 2, which are preferably circular and arranged coaxially with respect to a central axis 3.

[0012] The magnetic head 1 comprises an electric coil 5 and a magnetic core 6 in a housing 4, which are arranged coaxially with respect to the central axis 3. The housing 4 projects beyond the electric coil 5 and the magnetic core 6 with its wall 7 and sits with its lower end wall 8 (shown in the drawing) on ​​an upper end face 9 of the valve body 2. A vent hole 10 is formed in the wall 7 at a short distance below the plane of the electric coil 5 and the magnetic core 6.

[0013] The valve body 2 has an inlet 11 for the inflow of the medium and an outlet 12 for the outflow, which are preferably arranged coaxially. Associated with the outlet 12 is a valve seat 13, also arranged coaxially, which is formed on the valve body 2 and protrudes from the upper end face 9. In certain applications, it may be expedient to interchange the inlet and outlet, so that the medium is supplied via the illustrated outlet 12 and discharged via the illustrated inlet 11.

[0014] Above the valve body 2 are a valve chamber 14 and an armature chamber 15, which are hermetically separated by a bellows 16. The valve chamber 14, in which the valve seat 13 is provided, is bounded at the bottom by the valve body 2, at the top by the bellows 16, and at the periphery by the wall 7 of the housing 4. The armature chamber 15, to which the vent hole 10 is assigned, is bounded at the bottom by the bellows 16, at the top by the electric coil 5 and the magnetic core 6, and at the periphery also by the wall 7 of the housing 4.

[0015] The bellows 16 has a coaxial, cylindrical pleated body 17, the peripheral wall of which is formed from accordion-like folds 18 and which is closed by a bottom wall 19 on the lower end facing the valve seat 13. In the opening plane of the pleated body 17 opposite the bottom wall 19, there is a substantially planar flange part 20 which extends radially outward from the peripheral wall of the pleated body 17. The diameter of the pleated body 17 can be significantly smaller than the diameter of the flange part 20 and is preferably less than one-third of the flange part diameter. In the present embodiment, the bellows is arranged on the housing 4 of the magnetic head 1, with a peripheral edge region 21 of the flange part 20 being fixed to the wall 7.It is within the scope of the invention to design the valve body 2 with an upwardly directed wall and to attach the peripheral edge region 21 of the flange part 20 to this valve body wall or both to the latter and to the wall 7 of the magnetic head 1. Particularly in sensitive applications in the medical field, where high sterile requirements exist, it is expedient to manufacture the bellows 16 with its bellows body 17 and its base wall 19 entirely from an aseptic material, preferably PTFE.

[0016] On the lower side of the bottom wall 19 of the pleated body 17 facing the valve body 2, i.e., within the valve chamber 14, a preferably circular disk-shaped sealing body 22 is coaxially arranged, which is located directly above the valve seat 13. The sealing body 22 is expediently made of an elastic material, which preferably also has aseptic properties for sterile medical applications.

[0017] Provided in the armature chamber 15 is a plate armature 23 which, in the drawing, has a horizontally extending coaxial armature disk 24 and a vertically oriented coaxial web 25 which extends downwards towards the valve seat 13, so that the plate armature 23 is approximately T-shaped in cross-section. The web 25, whose diameter is substantially smaller than the diameter of the armature disk 24, but equal to or slightly larger than the diameter of the valve seat 13 and / or the sealing body 22, engages in the pleated body 17, wherein the lower web end face rests on the side of the base wall 19 opposite the sealing body 22 and is expediently firmly connected to the latter, and the inner side of the folds 18 rests on the web circumferential surface or is slightly spaced therefrom.

[0018] Furthermore, a relatively thin coaxial disc spring 26 is located in the armature chamber 15, which is preferably arranged in a plane between the armature disc 24 and the flange portion 20 of the bellows 16 and is aligned with them essentially horizontally in the drawing. Similar to the flange portion 20 of the bellows 16, the disc spring 26 is secured to the wall 7 of the magnetic head 1 by a peripheral edge portion 27. In this case, too, it is within the scope of the invention to design the valve body 2 with an upwardly directed wall and to fasten the peripheral edge portion 27 of the disc spring 26 to this valve body wall or both to the latter and to the wall 7 of the magnetic head 1.The disc spring 26 can, as shown in the drawing, be preloaded towards the valve seat 13 so that when the valve is de-energized, the web 25 of the plate armature 23 presses against the base wall 19 and the sealing body 22, closing the valve seat 13 and preventing the medium from flowing through the valve. In this case, the medium presses against the bellows 16, with the only effective pressure surface acting against the spring force being the area resulting from the mean diameter of the bellows body 17. This means that the force exerted by the medium pressure against the spring force is relatively small, so that the force exerted by the disc spring 26 can also be kept small to securely close the valve seat 13.To open the valve, the plate armature 23 is displaced upwards against the force of the disc spring 26 when current flows through the magnetic head 1, whereby the sealing body 22 lifts off the valve seat 13 and releases it, allowing the medium flowing into the valve chamber 14 through the inlet 11 to flow out through the outlet 12. Since the spring force required to close the valve seat 13 is relatively small, only a small force needs to be applied by the magnetic head 1 to open the valve seat 13. This has an overall positive effect on the valve and its application. The force loads are low, which greatly reduces wear. This results in a long service life for the valve with high functional efficiency. In addition, the low forces allow a high switching frequency to be achieved, while the structural design can be kept very small, resulting in a compact, space-saving design.

Claims

[1] Valve for gaseous and liquid media, having the following features: a) a valve body (2) with a valve chamber (14), a valve seat (13) provided therein, a sealing body (22) which can be pressed against the latter, at least one inlet (11) and at least one outlet (12) for the medium, b) a magnetic head (1) with a housing (4), an electric coil (5) and a magnetic core (6), c) a plate anchor (23) which is axially displaceable by means of an anchor plate (24) and to which a disc spring (26) is assigned, characterized by , d) that an armature chamber (15) is formed above the valve body (2), in which the plate armature (23) with the armature disc (24) and the disc spring (26) are mounted, e) that a vent hole (10) is assigned to the armature chamber (15), f) that the valve chamber (14) and the armature chamber (15) are hermetically separated by a bellows (16), g) that the armature chamber (15) is delimited by the bellows (16), the electric coil (5), the magnetic core (6) and at the periphery by the wall (7) of the housing (4), h) that a flange part (20) of the bellows (16) is fixed with a peripheral edge region (21) to the wall (7) of the housing (4) of the magnetic head (1), i) that the disc spring (26) is arranged in a plane between the armature disc (24) and the flange part (20) of the bellows (16). [2] Valve according to the preceding claim, characterized by that the plate armature (23) on the armature disc (24) has a web (25) directed coaxially towards the valve seat (13) and is T-shaped in cross-section. [3] Valve according to claim 2, characterized by that the web (25) of the plate anchor (23) engages in a fold body (17) of the bellows (16) and rests with its web end face against a floor wall (19). [4] Valve according to one of claims 2 and 3, characterized bythat the web (25) of the plate anchor (23) is smaller in diameter than the anchor disc (24). [5] Valve according to claim 3, characterized by that the sealing body (22) for the valve seat (13) is arranged on the side of the bottom wall (19) of the fold body (17) facing away from the plate anchor (23). [6] Valve according to one of the preceding claims, characterized by that the disc spring (26) is fixed with a peripheral edge part (27) to the wall (7) of the magnetic head (1) and / or the valve body (2). [7] Valve according to one of the preceding claims, characterized by that the plate anchor (23) with the anchor plate (24) and the web (25), the disc spring (26) and the bellows (16) with the flange part (20), the pleated body (17) and the sealing body (22) are arranged coaxially with respect to a central axis (3). [8] Valve according to one of the preceding claims, characterized bythat the bellows (16) is made of a material suitable for aseptic applications.

Images