The invention relates to an actuating device, in particular for actuating valves that can be connected externally, comprising a housing and a coil body arranged therein and having a coil. winding, where said coil body encloses at least in part a pole tube to whose one free end a pole core is connected, with an armature which is guided to be longitudinally displaceable at least in the pole tube within an armature space, and which interacts with an actuating part for actuating the respective valve part, the pole tube being designed as a receiving sleeve for the armature, said receiving sleeve being fixed with its free end region at a fixed bearing point.
DE 10 2004 051 332 A1 discloses a generic actuating device. In the known solution, the pole tube on its one free end which projects out of the housing of the actuating device is provided with a flanged edge against which the armature can be supported in its one end-side travel position, the flanged edge leaving a center opening exposed into which a pressure equalization channel of the armature discharges which on its opposite side can be supported on the pole core in whose direction the pressure equalization channel discharges on its other side. For this purpose, a loose bearing point is formed by the coil body and delimited by the housing parts for the free end edge of the pole tube, which edge is directed to the outside.
On the opposite end, the pole tube has a flanged edge of less curvature which is directed in the opposite direction, and with which it is fixed in position between the coil body and the pole core both axially and also radially in a fixed bearing point. As a result of the deflections toward the free edges of the pole tube, which is designed as a receiving sleeve for the armature and which is longitudinally displaceable, the pole tube is able to produce a certain longitudinal tolerance equalization in order to form a fitted mounting for parts of the actuating device. But as a result of the defined clamping site of the receiving sleeve as the pole tube at the fixed bearing point between the pole core and the coil body, these tolerance equalization possibilities are limited. In order to seal the interior of the actuating device relative to the exterior, on the inner periphery of the receiving sleeve as the pole tube there is a sealing system, preferably in the form of an elastomer gasket which, mounted in the outer groove of the pole core, ensures sealing between the pole core and the pole tube. If the elastomer gasket has not been correctly installed or it was forgotten in installation, the sealing site can fail and the interior of the actuating device is no longer sealed media-tight relative to the exterior. This failure case can also occur when the sealing system is worn and therefore has become unusable due to long-term use.
To remedy the defect of the limited tolerance equalization possibility, DE 10 2005 061 184 A1 for a likewise generic actuating device has proposed forming the aforementioned flanged edge of the pole tube as a closed bottom part of a receiving sleeve which, supported by the pole core, is in contact with the latter, the bottom part of the pole tube being able to fit into the pole core such that it maintains its location, even if the armature for actuating a valve which can be connected to the actuating device moves back and forth and, in doing so, presses especially on the bottom part or is lifted off it by pulling itself Since the flanged edge no longer borders an annular passage site, as shown above, but rather is closed, in this case, use for high pressures is possible since, in addition to pressure tightness, a stiff, loadable pole tube system is formed.
By means of the defined contact of the bottom part of the pole tube with the pole core, a type of fixing is achieved which enables tolerance equalization elsewhere on the pole tube in a widely drawn region. At the same time, it is provided that the pole tube on its free end discharges into a bead-shaped flange which is supported on the housing of the actuating device. The bead part of the flange is designed as a round bead; this makes it possible to position the free end region of the bead-shaped flange between the housing of the actuating device and housing parts of the adjoining valve body by clamping, and, as a result of the elastically resilient bead body, a type of articulation is implemented along which, especially in the axial direction, the pole tube with its installation length can be fitted within the coil body and the pole core. Between the elastically resilient bead body and the connected valve housing of the valve in turn there is an elastomer gasket which is designed to ensure a media-tight seal between the interior of the actuating device together with the valve relative to the exterior. This known sealing system can also lead to the above-described defects of the lack of media tightness.
On the basis of the prior art, the object of the invention is to further improve the known solutions while maintaining their advantages, specifically reliable, long-lasting actuating operation such that a media-tight separation from the interior of the actuating device relative to the exterior is ensured with low mechanical effort and therefore cost-efficiency. This object is achieved by an actuating device having the features of claim 1 in its entirety.
In that, as specified in the characterizing part of claim 1, the fixed bearing point is formed from two support parts of the pole core which delimit a receiving gap between them in which the free end region of the receiving sleeve is fixed by clamping, a media-tight separation between the interior of the actuating device and the exterior is achieved. For media-tight separation it is also a contributory factor that the receiving sleeve in its preferred configuration is cup-shaped and therefore has a bottom part which is closed in itself. The entire pole tube with respect to the special configuration of the fixed bearing point along its internal periphery does not need a further sealing system, inasmuch as said system cannot fail or cannot be forgotten either. In addition, this solution saves production and installation costs with the elimination of the additionally required sealing system for the pole tube.
In one preferred embodiment of the actuating device according to the invention, one support part is formed from the constriction site of the pole core which is smaller in diameter than the remaining outside diameter of the pole core in the region of the fixed bearing point, the step-shaped transition region resulting therefrom forming a caulk surface as another support part of the pole core. Accordingly, a media-tight, especially gas-tight, fixed bearing point can be achieved by inserting the crimped end edge of the pole tube into the constriction site in a first production step and by caulking the step-shaped transition region over the outside of the pole tube in a second step so that a positive and non-positive connection is achieved. These production steps can be economically implemented.
In another preferred embodiment of the actuating device according to the invention, it is provided that at a loose bearing point for the receiving sleeve a reset means acts on the latter and applies a force to the receiving sleeve, which is oriented away from the fixed bearing point. In this way, tolerance equalization for the entire system can be achieved within a very widely drawn framework, and this amount of equalization can be stipulated by way of a suitable selection of the reset means. Regardless of the possible production tolerances of the individual components of the actuation device, the associated tolerance can thus be compensated and, in this respect, individually equalized via the reset means acting on the receiving sleeve.
Although the reset means attempts to pull the pole tube out of the fixed bearing point, this does not affect the media-tight clamping by way of the caulked pole core material since the free end region of the pole tube is transferred, as a type of thrust bearing, by way of an arc-shaped transition region out of the constriction site into a guide section which, with a diameter which has been widened relative to the outside diameter of the constriction site, provides for permanent support between the pole tube and the pole core in this region and thus at the same time ensures relief for the fixed bearing point over a longer path. This axially running guide section which merges with the bent transition region moreover implements a longer sealing distance which acts as an escape barrier for the respective medium even in the form of a gas.
In another, especially preferred embodiment of the actuating device according to the invention, the fixed bearing point for the receiving sleeve is provided on its free end edge and is caulked accordingly with the pole core as shown. The loose bearing point on the opposite end of the pole tube is arranged in the region of the closed bottom part, particularly at the point at which the pole tube emerges from the housing of the actuating device, and supporting is achieved by the coil bodies and/or by the housing parts which are penetrated by the pole tube. By the action of the reset means, preferably in the form of an energy storage device, for example, in the form of a disk spring, on the loose bearing point, the receiving sleeve with its inner periphery is accordingly drawn lengthwise and equalizes possible unevenness along its inner periphery. In this respect, the receiving sleeve as a pole tube is kept permanently under tensile stress so that sealing contact is achieved between the inner periphery of the pole tube and the outer periphery of the pole core along the indicated guide distance. Since especially the elastomer parts of the sealing system can be damaged upon contact with metallic wall parts, the desired media-tightness is ensured by omitting this sealing system in the metallic wall region.
Other advantageous configurations of the actuating device according to the invention are the subject matter of the other dependent claims.
The embodiment according to the invention is detailed below using exemplary embodiments as shown in the drawings. The figures are schematic and not to scale.
a, 4b, and 4c show, in a longitudinal section in a perspective top view and in a front view, a second embodiment of an injection solution which has been modified relative to
a, 5b, and 5c show, in correspondence to
a, 6b, and 6c show, in correspondence to
The actuating device which is shown in a longitudinal section in
To energize the coil winding 14 of the coil body 12, which preferably consists of at least one conductive copper wire, there is a plug part 30 which is preferably permanently connected to the remaining parts of the housing 10 by way of a sealing compound 32. Viewed in the direction of looking at
If the coil winding 14 and therefore the coil are energized by means of the plug part 30, the armature 22 then is moved into its actuated position shown in
But even when the current drops out, as a result of residual magnetism processes in the pole core 20 and in the pole plate 34, it can happen that the armature 22 with its one free face remains adhering to the adjacent face of the pole core 20 facing it. To avoid this, between the two faces within the armature space 22 an anti-adhesion means 42 is inserted which encompasses the rod-like actuating part 26 with a radial distance in order to effectively execute decoupling. The rod-shaped actuating part 26 is penetrated by a center channel 44 which extends along the longitudinal axis 46 of the armature 22 and the actuating part 26, which in this case also forms the optional axis of motion. The indicated middle channel 44 thus emerges into the exterior on the two opposite faces 48, 50 of the actuating part 26. In particular, the center channel 44 on the right face 50 of the actuating part 26 leads into an open space 52 of the armature 22, the open space 52 in turn leading into the armature space 24, carrying pressure and medium. In the region between a sealing site 54, which also forms a guide for the front end of the actuating rod 26 and the armature 22, there is a cross channel 56 which with its one end discharges into the center channel 44 and with its other end emerges into a center space 58 which is encompassed by the pole core 20.
The components including the center channel 44, cross channel 56, center space 58, open space 52, and armature space 24 form a type of pressure equalization system which is connected to a valve unit which is not detailed and compensates the pressure media originating from the valve unit such that the travel motion of the armature 22 together with the actuating part 26 is not adversely affected by possible pressure differences. Optionally, the pressure media guided in this way can also effectively support the actuating force to be applied by the armature 22 as a result of different area ratios. In the region of the point of separation 18, the pole core 20 with a lug-like annular projection 60 overlaps the stepping 62 of the armature 22 offset in this region such that in each travel position of the armature 22 it is guided within the annular projection 60 so that the size of the point of separation 18 changes depending on the direction of travel of the armature 22.
The rod-like actuating part 26 is formed from an injectable material which is injected onto the armature 22, especially as shown in
The injection mold 66 as shown in
The embodiment as shown in
The embodiment as shown in
In the embodiment as shown in
As
As shown especially by
The flanged edge 104 enhances this effect by forming an elastically resilient articulation. A peripheral gap 110, into which medium can travel, leads into the edge 104 formed in this way; this in turn promotes stiffening of the entire system in this region. But it is especially advantageous that for the pole tube 16 in any temperature state, tolerance equalization is created by an elastically resilient reset means 112 in the form of an energy storage device, for example, formed from components of a disk spring 114, of which
The reset means 112, preferably in the form of a disk spring 114, with its one end acts effectively on the free face of the housing jacket 38 and is supported with the other free end on a deflection region 116 at which the cylindrical pole tube wall 106 passes into the projecting edge 104. With respect to a high degree of corrosion resistance, the pole tube 16 is formed from a high- grade steel material, and the reset means 112 used also has the advantage that when vibrations occur on the actuating device, the pole tube 16 is decoupled relative to the housing 10. The projection selected to the right for the edge 104 relative to the free face of the housing jacket 38 is chosen such that the respective reset means 112 with its pretensioning can reliably act on the pole tube 16 and that the latter can be located on the remaining housing 10, saving installation space. The indicated offset 108, moreover, ensures that the pole tube 16 is reinforced in its pertinent bottom part region 36 so that residual deformations cannot occur in the event of striking of the armature 22.
The solution, as shown in
Since these actuating devices are also used to some extent in the high temperature range, and this fundamentally damages the elastomer material of seals, a cost-favorable sealing alternative is implemented here. Due to the arc-shaped transition region 120, moreover, the pole tube is reliably guided without major kinks in the direction of the annular projection 60 on the outer periphery of the pole tube 22 so that unnecessary material stress for the thin-walled pole tube material does not occur. With respect to this guide distance 126 and the guide centering by way of the reset means 112 on the free end region of the pole tube 16, it is ensured that bulging processes which could possibly limit the free mobility of the armature 22 with its actuating part 26 do not occur.
The actuating device according to the invention is intended especially in the low pressure range for use in pneumatic valves even in the high temperature range; with a corresponding modification, however, other applications are also conceivable, especially for hydraulic valves. The very lightweight actuating device has very short switching and reaction times, and extremely high load cycles, which can be in the range of multiples of millions, can be achieved.
Number | Date | Country | Kind |
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10 2008 030 451.4 | Jun 2008 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2009/003939 | 6/3/2009 | WO | 00 | 11/3/2010 |