EP2158596B1 - Electromagnetic actuating device - Google Patents

Description

The present invention relates to an electromagnetic actuator according to the preamble of claim 1. Such devices are known in the art, such as from EP 1 002 938 A , which is considered to be the closest prior art, known and are used for a variety of control tasks, such as in the context of internal combustion engines.

Due to limited installation space at a place of use there is often the need to realize a generic actuator sufficiently compact with a plurality of (typically selectively, ie independently controllable) ram units for a respective setting task, so that on the one hand a sufficient electromagnetic functionality is ensured (for example with respect on the necessary stroke of the ram units and reaction or switching time), on the other hand there is no unwanted mutual influence mechanically or electromagnetically.

It is therefore known from the prior art to realize actuating tasks which require a plurality of actuator units with the aid of individual actuator units fastened or provided independently of one another, which leads to increased configuration or assembly effort and usually only the compactness of the overall arrangement is limited.

This problem is aggravated by the fact that often provides the intended, requiring engagement of a plurality of ram units use environment that the ram units closely adjacent each other and often only a predetermined Maximum distance from each other must be spaced; This is often not solvable with individual, individually attached actuator units or only with restrictions.

An example of a known actuator unit shows about the German patent application 102 40 774 the applicant.

Object of the present invention is therefore to provide an electromagnetic actuator with a plurality of electromagnetic actuator units according to the preamble of the main claim, which is particularly beneficial in use at sites with limited installation space and in particular under conditions of use, which specify a limited maximum distance of the plunger units from each other ,

The object is achieved by the electromagnetic actuator with the features of the main claim and by the use of the features of the independent use claim 11; advantageous developments of the invention are described in the subclaims.

In an advantageous manner according to the invention, initially the plurality of actuator units (wherein a particularly preferred embodiment of the invention provides at least three actuator units with correspondingly three slide units) are provided in a preferably cylindrical and / or hollow cylindrical housing. According to the invention, the drive of the elongate (even preferably cylindrical, more preferably realized from a metal material) ram units takes place in that the ram units sit on an engagement surface of a respective associated actuator unit (preferably there by means of magnetic effect Adhere), wherein the engagement surface typically forms the distal end of an anchor unit of the respective actuator unit.

According to the invention, it is now possible to solve the problem of a compact arrangement of the ram units side by side so that - when the engagement surfaces of adjacent actuator units are driven parallel to one another - respective ram units interacting with their engagement surfaces interact with the engagement surfaces so eccentrically that the most compact arrangement preferably parallel to each other guided ram units takes place, therefore - according to predetermined setting or use conditions - minimum axial distances of the ram units can be realized to each other.

Within the scope of a preferred embodiment of the invention, it is advantageously provided that the common housing accommodating the actuator units cooperates with a housing guide section (guide tube) at the end, which offers guides for the majority of tappet units, typically in the form of through holes extending parallel to each other.

According to a preferred embodiment of the invention, at least one of the actuator units is space-saving, at the same time optimizes electromagnetically realized by means of a flux-conducting actuator shell unit, which is formed bow-shaped. In this way, the packing density of the plurality of actuator units in the common housing can be further increased, in particular in that the actuator units are arranged so that respective Aktorenmanteleinheiten adjacent actuators do not touch each other.

In the context of preferred developments of the invention, it is also advantageous to realize the armature unit from a widened armature section, which has a permanent magnet and at least one armature disc provided thereon (preferably for forming the engagement surface), this widened armature section then merging axially into an elongate armature tappet section, which is guided in a core (having a corresponding guide bore). The core (core unit) can then itself preferably a further training provided compression spring, which acts against the anchor record and / or have a through hole for fluids (in particular air) for further motion optimization by means of pressure compensation. In particular with regard to a switching time optimization at low temperatures, the compression spring according to further development has proven to be advantageous; in the retracted state of the anchor unit this is biased by the Ankerstößelabschnitts. As soon as the coil unit is energized, the holding force of the permanent magnet is first weakened at the core. In addition, the repulsive force between the coil unit and permanent magnet, which then shifts by the spring force and the repulsion between the permanent magnet and the coil unit of the armature, as soon as the magnetic field is completely built up.

According to a further preferred embodiment, at least one of the (metallic) ram units is provided with several sections in the axial direction: a first, magnetically optimized section of the ram unit forms the engagement-side end face, ie acts with the Engagement surface of the armature unit together, while an opposite second tappet portion, such as for the purpose of cooperating with a downstream actuator, is optimized in terms of hardness or wear properties. Such a realization of several sections of the plunger unit can be done either by suitable material influencing a one-piece unit, alternatively, in the context of preferred developments, the plunger unit can be assembled together by means of several individual sections, in this respect referred to as the prior art to the German utility model application 20 2006 011 905 of the Applicant becomes. Thus, it is suitable according to further development favorable to realize the first magnetically optimized portion of the plunger unit by means of a soft magnetic material, more preferably ferromagnetic metals (such as iron, cobalt, nickel) are low to implement. In contrast, it is preferred within the scope of the invention according to the invention to realize the second plunger section of austenitic material, in which case in particular methods of cold deformation, the hardness of the second section can further increase. It is not necessarily the ram unit of two separate workpieces to realize, but may be provided in the context of the present invention, as the second, wear-optimized section by a (eg by a heat treatment) hardened portion of an otherwise soft magnetic material form.

During the present invention, in particular for a realization of actuating tasks by means of three mutually parallel to the axis and extending in a plane ram units is suitable, for example, for the camshaft adjustment of an internal combustion engine, the present invention is not limited thereto. In particular, the distance between two mutually guided ram units within the scope of the invention can also be advantageously optimized, just as implementation forms are conceivable in which more than three ram units are driven in a compact and space-optimized manner by an associated actuator unit. In addition, while the axis-parallel guidance of the plunger units should be the typical embodiment, the present invention is not limited thereto; Rather, it is sufficient for realizing the advantages according to the invention, if only one component of the motion vector of each ram unit in the direction of adjustment, in particular also skewed or otherwise mutually inclined directions of extension of the ram units are included in the present invention. The leadership of the plunger units in a common housing is the typical implementation, conceivable and included in the invention, however, are also variants in which respective plunger units are guided in separate, corresponding to each other adjacent individual housings.

The result of the present invention in a surprisingly simple and elegant way, an arrangement that combines compact design with ease of installation, high reliability and optimal switching time and magnetic properties.

Fig. 1:

eine Perspektivansicht der elektromagnetischen Stellvorrichtung gemäß einer ersten bevorzugten Ausführungsform der Erfindung (mit abgenommenem Gehäuse);

Fig. 2:

eine Rückansicht/Draufsicht auf die Anordnung gemäß Fig. 1;

Fig. 3:

eine Seitenansicht der Anordnung gemäß Fig. 1;

Fig. 4:

eine Schnittansicht durch das Ausführungsbeispiel gemäß Fig. 1 bis Fig. 3 (mit Gehäuse) entlang der Schnittlinie B-B in Fig. 5;

Fig. 5:

einen Längsschnitt durch die Vorrichtung gemäß Fig. 4 entlang der Schnittlinie A-A;

Fig. 6:

einen Längsschnitt durch eine Aktuatoreinheit gemäß dem Ausführungsbeispiel der Fig. 1 bis Fig. 5;

Fig. 7, Fig. 8:

um 90° gedrehte Detailansichten des bügelförmigen Flussleitelements (Aktormanteleinheit) zur Verwendung in der Aktoreneinheit gemäß Fig. 6;

Fig. 9, Fig. 10:

eine Perspektiv- sowie Seitenansicht zum verdeutlichen des Zusammenwirkens zwischen einer Aktoreneinheit (Fig. 6 bis Fig. 8) mit einer exzentrisch sowie teilflächig zusammenwirkenden Stößeleinheit;

Fig. 11:

eine Perspektivansicht der elektromagnetischen Stellvorrichtung gemäß einer zweiten Ausführungsform der vorliegenden Erfindung mit zwei Stößeleinheiten;

Fig. 12:

ein Längsschnitt durch die Vorrichtung gemäß Figur 11;

Fig. 13, Fig. 14:

Detailansichten zum Verdeutlichen des Zusammenwirkens einer Aktoreneinheit des Ausführungsbeispiels der Fig. 11 und Fig. 12 mit einer Stößeleinheit;

Fig. 15, Fig. 16:

Schemadiagramme zum Verdeutlichen des magnetischen Zusammenwirkens der Permanentmagneten zweier benachbarter Aktoreneinheiten im eingefahrenen Zustand (Fig. 15) bzw. ausgefahrenen Zustand einer Aktoreneinheit (Fig. 16);

Fig. 17:

ein Längsschnitt analog Fig. 5 zum Verdeutlichen einer weiteren Ausführungsform mit Stößeleinheiten, welche aus mehreren funktionalen Abschnitten bestehen; und

Fig. 18, Fig. 19:

eine Seiten- bzw. Perspektivansicht einer Variante der vorliegenden Erfindung einer relativ zu einer Aktor-Bewegungsrichtung geneigten Stößeleinheit, welche zudem eine ballig gewölbte Stirnfläche zum Zusammenwirken mit dem Aktor aufweist.

Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the drawings; these show in:

Fig. 1:

a perspective view of the electromagnetic actuator according to a first preferred embodiment of the invention (with the housing removed);

Fig. 2:

a rear view / top view of the arrangement according to Fig. 1 ;

3:

a side view of the arrangement according to Fig. 1 ;

4:

a sectional view through the embodiment according to Fig. 1 to Fig. 3 (with housing) along the section line BB in Fig. 5 ;

Fig. 5:

a longitudinal section through the device according to Fig. 4 along the section line AA;

Fig. 6:

a longitudinal section through an actuator unit according to the embodiment of the Fig. 1 to Fig. 5 ;

Fig. 7, Fig. 8:

rotated by 90 ° detail views of the bow-shaped flux guide (actuator shell unit) for use in the actuator unit according to Fig. 6 ;

Fig. 9, Fig. 10:

a perspective and side view to illustrate the interaction between an actuator unit ( Fig. 6 to Fig. 8 ) with an eccentric and partial co-operating ram unit;

Fig. 11:

a perspective view of the electromagnetic actuator according to a second embodiment of the present invention with two plunger units;

Fig. 12:

a longitudinal section through the device according to Figure 11;

Fig. 13, Fig. 14:

Detail views to illustrate the interaction of an actuator unit of the embodiment of 11 and FIG. 12 with a ram unit;

Fig. 15, Fig. 16:

Schematic diagrams to illustrate the magnetic interaction of the permanent magnets of two adjacent actuator units in the retracted state ( Fig. 15 ) or extended state of an actuator unit ( Fig. 16 );

Fig. 17:

a longitudinal section analog Fig. 5 to illustrate a further embodiment with plunger units, which consist of several functional sections; and

Fig. 18, Fig. 19:

a side or perspective view of a variant of the present invention of a relative to an actuator movement direction inclined ram unit, which also has a convexly curved end face for cooperation with the actuator.

The FIGS. 1 to 3 to the first embodiment show how three actuator units 10, 12, 14 in a housing (shown only a circular housing cover 16 as a yoke) are distributed so that the actuator units 10 to 14 on a hollow cylindrical inner wall of a housing shell 18 (in the FIGS. 1 and 3 not shown) abut. On the housing cover (yoke) 16 sits an engagement-side, flat housing portion 20, which has three juxtaposed in an extension plane breakthroughs for guiding three ram units 22, 24, 26, which are mounted axially parallel in the manner shown and in the manner to be described by an associated the actuator units 10, 12, 14 are selectively driven.

With a typical outer housing diameter of 40 mm, a maximum diameter d ( FIG. 2 ) one of the actuator units 10 to 14 about 17 mm; the arrangement shown can thus with assumed diameter of the elongated-cylindrical ram units 22, 24, 26 of 5 mm in the in FIG. 3 shown way realize a mean axial distance a of the plunger units of 7 mm, according to the installation and setting conditions to a downstream unit, in the present embodiment, a camshaft control for an internal combustion engine, which by the three plungers 22, 24, 26 can be actuated (not shown).

The picture views of the FIGS. 4 and 5 (different from the FIGS. 1 or 3 is here also the cylindrical housing shell 18 shown) illustrate in particular the geometric relationships in the transition between the actuator units 10 to 14 (more precisely, the engagement-side engaging surfaces 28, 30, 32 of the actuator units) and each directed thereto end faces 34, 36 and 38: it turns out, cf. in particular the sectional view of Fig. 4 in that the tappet units 22, 24, 26 respectively rest eccentrically on the disc-shaped engagement surfaces 28 to 32, wherein the likewise circular end faces 34 to 38 in the in Fig. 4 shown partially protrude beyond a respective outer edge of the engaging surfaces 28 to 32 of the actuator units. In this way, then the geometry shown can be achieved, namely closely juxtaposed, but independently movable ram units 22 to 26 with minimized distance from each other (in the embodiment, a = 7 mm, see Fig. 3 ). In this case, have in the illustrated embodiment, such as in the Fig. 5 shown, plane faces. However, these may also have a different contouring, such as a convex (convex) outer shape, to take account of a possible circumstance that in alternative embodiments, the direction of movement of the actuator units does not match the direction of movement of the plunger units, but about the plunger units (also relative to each other ) with respect to the direction of movement of the actuator units (or their engagement surfaces 28 to 32) are inclined.

The FIGS. 6 to 8 illustrate constructive details of the three actuator units 10 to 12: one of an elongated, cylindrical armature tappet portion 40 and a self-armature disc 42, a permanent magnet disc 44 and a pole plate 46 layered formed widened anchor portion 47 realized anchor forms on the outer surface of the pole disk 46 one of the engagement surfaces 28 to 32 and is guided in an elongated hollow cylindrical core member 48, the armature disk 42 opposite, an annular collar portion 50 is formed and along its axial extension direction has a through hole 52, which, in order to optimize the fluid flow, allows, for example, a free flow of air in the arrangement and, moreover, is designed to receive a compression spring 54, which in the in Fig. 6 shown stop state of the armature biases this in its rightward direction of movement.

The yoke element 48 is initially surrounded by a coil support 56 and a winding 58 having coil unit, which in turn is surrounded in sections in the circumferential direction of a bow-shaped flux guide 60, which at one end offers a breakthrough for a narrow end of the yoke element 48, the other in two free Legs 62, 64 opens, which limits the travel of the armature (and thus also the pole plate 46 with engagement surface).

The FIGS. 7 and 8 show the bow-shaped flux guide 60 in detail; the legs 62 and 64 are elongated cylindrical section-shaped and sit integrally on a bottom portion 66. Variants of this embodiment in the context of the present invention also provide that the bow-shaped flux guide 60 has only one leg and another of the pair of legs 62 and 64 accounts can. Although this leads to a reduction of the magnetic properties, but potentially allows even further densification of a plurality of actuator units formed therewith into a compact structure.

The FIGS. 9 and 10 illustrate as an isolated representation of an actuator unit with a plunger unit, as - with virtually undisturbed electromagnetic functionality - the bow-shaped flux guide 60 in the circumferential direction only partially opposite the arrangement of coil unit, yoke element and armature unit surrounds, at the same time the possibility for the ram unit 22 shown opens at the edge with a part of the end face on the engagement surface 28 also to protrude.

The FIG. 2 illustrates in this context, as the elongated-disc-shaped bottom portions 66 and the legs 62, 64 of the respective flux guides are placed so that - to minimize the packing density in the hollow cylindrical housing - no mutual influence of the flux guide 60 takes place, but the (smaller) outer diameter The coil units can be effectively used to minimize the space.

The FIGS. 11 to 14 show an alternative embodiment of the present invention according to a second embodiment. This embodiment provides only two plunger units 70, 72, which are moved by respectively associated actuator units 74 and 76, respectively. The actuator units 74 and 76 correspond constructively based on the FIGS. 6 to 8 explained realization and sit in the illustrated embodiment in a common housing 78 which has a flat contour (the reference numeral 80 shows schematically a mounting flange for the housing assembly 78).

As in particular the sectional view of FIG. 12 illustrates, in turn, the elongated-cylindrical plunger units 70, 72 are guided in a front housing portion 82 so that they are parallel to each other while minimizing their axial distance (again about 7 mm), wherein like the FIG. 12 can detect, in the inventive manner, the ram units 70, 72 each eccentrically on the formed by a respective pole plate 46 outer engagement surfaces sit (or adhere there magnetically). In the exemplary embodiment shown, it is also clear that here the plunger units 70 and 72 respectively consist of two sections, a first, magnetically optimized section 84 and a second section 86 which abuts in the longitudinal direction and which is adapted in particular for optimized interaction with an engagement element on the end, such as by suitable curing (or other forms of wear resistance or the like). In the illustrated embodiment, a respective one of the ram units 70, 72 is assembled from two suitable metal materials for the sections 84, 86, respectively; Other alternatives for realizing the multiple sections are conceivable, as well as a use of the two-piece ram units in the context of the first embodiment of the FIGS. 1 to 10 (In this respect shows the FIG. 17 as a further embodiment, this variant, wherein identical functional components provided with the same reference numerals and the plunger units 22 ', 24' and 26 'are corresponding two-part variants). With regard to the realization of the first section 84 and the second section 86 is on the DE 20 2006 011 905 U1 the applicant referred; Thereafter, the use of a soft magnetic or ferromagnetic material for the first section is particularly favorable, while about an austenitic material for the realization of the second section is favorable and both sections are permanently connected to each other by suitable joining methods. Alternatively, in the context of preferred refinements, it is also possible to realize, for example, the second section by hardening or the like measures of an otherwise magnetically favorable (eg soft-magnetic) material.

For the embodiment of 11 and FIG. 12 clarify the detail views of the FIGS. 13 and 14 again the eccentric and also laterally superior seating of the plunger units on or on a respective engagement surface.

The FIGS. 15 and 16 illustrate a magnetic interaction between two adjacent actuator units, this being true both for the first embodiment with three ram units, as well as for the second embodiment with two plunger units applies: the FIG. 15 schematically shows how in the inserted state of two adjacent actuator units, the respective permanent magnet disc 44 (magnetized in the axial direction) is in each case at the same height, in other words and as by the double arrows in Fig. 15 shown, it comes to a repulsion effect of the respective same magnetic poles from each other, so that a repulsive force between the respective anchor units in this operating condition exists. Once one of the actuator units from its rest position (ie approximately corresponding FIG. 6 ) is moved, it comes between the south pole of the left permanent magnet and the north pole of the right permanent magnet to attraction (illustrated by the long double arrow), while still the same-pole permanent magnet sections repel each other (short double arrows). As a result, this configuration then improves the dynamic behavior of the exemplary embodiments described.

The present invention has been described by way of example only with reference to the embodiments; In the illustrated embodiment, with a diameter of the housing shell of about 40 mm, an axial distance of only 7 mm of three adjacent cylindrical ram units realized (each having 5 mm in diameter). With an effective stroke of the actuator movement of 4 mm, a switching time between approx. 20 and 22 msec (12 to 22, up to 100ms at -35 ° C) can be achieved.

While the above-described embodiments assumed that actuator and ram unit are each guided and aligned parallel to each other, the present invention is not limited thereto; Rather, it is possible in the context of preferred developments that the plunger units are inclined relative to the actuators or their directions of movement, as well as the plunger units may be inclined relative to each other (ie, for example, are skewed), as well as in principle is not excluded that the Direction of movement of the plurality of actuators is inclined to each other. The FIGS. 18 and 19 illustrate as a side or perspective view of such a variant, namely a tilted in its direction of movement relative to the actuator movement direction plunger, which also frontally in its engagement area to the actuator has no plane, but a spherical (concave) end face.

Concrete sits here, analogous to the representation of Fig. 9, 10th (In this respect, the reference numerals for the actuator unit 60 remain) on a ram unit 90 on the engagement surface 28 of the actuator unit, however, deviating from the ram unit 22, the ram unit 90 engages the engagement side with the end face 28 forms a convex, crowned end portion 92, so that in the end region of the disc 28 a secure interaction and a reliable power transmission between the units is ensured. The from the representations of Fig. 18, 19 recognizable geometry also illustrates that a running through the longitudinal axis of the plunger unit 90 direction of movement of the plunger unit (this is - not shown - correspondingly guided in an associated housing) is realtiv inclined to the longitudinal or axial direction of the actuator unit +. Again analogous to the embodiment of Fig. 9, 10th the plunger unit 90 sits on the disk-shaped surface 28 and can be held there, for example, by permanent magnet action.

The present invention is not limited to the configurations shown with two or three plunger units, but is in principle also suitable for a larger number of actuator and associated plunger units. Although a preferred field of application of the present invention in the realization of control tasks in internal combustion engines, such as in the camshaft adjustment, in principle, the scope of the present invention is unlimited and particularly advantageous where only a small installation space for a plurality of actuator units available stands, but at the same time each ram must meet their purpose with only a very small distance from each other.

Claims (11)

1. Electromagnetic actuation device comprising a plurality of electromagnetic actuator units (10, 12, 14) which can be selectively controlled in order to exert an actuating force on a corresponding plurality of elongated tappet units (22, 24, 26), the actuator units (10, 12, 14) being provided in a housing (18, 20; 78, 82), preferably axially parallel to each other in their actuation direction, or being provided in separate, adjacent individual housings, each actuator unit forming an engagement surface which is planar at least in portions and axially movable in the actuation direction at an engagement end facing one of the associated tappet units (22, 24, 26) and an engagement-side end face (34, 36, 38) of each of the tappet units (22, 24, 26) interacting with the engagement surface (28, 30, 32), characterised in that at least one of the plurality of tappet units (22, 24, 26) rests with the engagement-side end face (34, 36, 38) thereof eccentrically, in particular with only a partial face thereof, on the engagement surface (28, 30, 32) of the associated actuator unit (10, 12, 14), in particular being magnetically attached to said surface.
2. Device according to claim 1, characterised in that the plurality of actuator units (10, 12, 14) are provided directly adjacent to each other in the interior of the housing which has a hollow cylindrical configuration, at least in portions, in such a manner that the actuator units (10, 12, 14) bear against the housing inner wall.
3. Device according to either claim 1 or claim 2, characterised in that at least one of the actuator units (10, 12, 14) has an armature unit which comprises a permanent magnet (44) and forms the engagement surface (28, 30, 32) at the end, which armature unit can be moved by applying current to a stationary coil unit (56, 58).
4. Device according to claim 3, characterised in that the coil unit is enclosed by an actuator casing unit (60), which has a cylindrical or hollow cylindrical configuration, at least in portions, and conducts magnetic flow, in such a manner that the engagement surface (28, 30, 32) can be moved in an open end of the actuator casing unit.
5. Device according to claim 4, characterised in that the actuator casing unit is configured in a stirrup shape in such a manner that a free limb (62, 64) of the actuator casing unit forms a peripheral boundary of the armature unit and of the coil unit, which boundary is configured in the shape of a hollow cylinder portion.
6. Device according to any of claims 3 to 5, characterised in that the armature unit has a widened armature portion (46), comprising the permanent magnet means, axially outside of the coil unit, and an elongated armature tappet portion (40) resting thereon which is guided at least in portions in an elongated core unit (48) of the actuator unit (10, 12, 14), which core unit is enclosed by the coil unit.
7. Device according to claim 6, characterised in that the core unit (48) is made of magnetic material and/or has a passage (52), in particular a through-hole (52), which makes it possible to balance fluid pressure.
8. Device according to any of claims 3 to 7, characterised in that the armature unit is guided against the force of a spring which is preferably axially provided, in particular a spring (54) acting against the armature tappet portion (40) and/or provided in the passage (52).
9. Device according to any of claims 1 to 8, characterised in that the plurality of the electromagnetic actuator units (10, 12, 14) and the corresponding plurality of tappet units (22, 24, 26) amount to at least 3, and the tappet units (22, 24, 26) are guided relative to the actuator units (10, 12, 14) in such a manner that respective longitudinal axes of the tappet units (22, 24, 26) lie in a common plane.
10. Device according to any of claims 1 to 9, characterised in that at least one of the tappet units (22, 24, 26) in the region of the engagement-side end face (34, 36, 38) forms a first, in particular ferromagnetic, portion (84) which is optimised in terms of material for magnetic interaction with the associated actuator unit (10, 12, 14), and at the end, a second, in particular austenitic, portion (86) which is hardened in terms of material and/or is optimised in terms of wear, and is opposite the first portion along the direction of extension.
11. Use of the device according to any of claims 1 to 10 for actuation tasks at an internal combustion engine, in particular for camshaft adjustment.

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