Electromagnetic actuating device which is monostable in the currentless state and use of such an actuating device

Abstract

An electromagnetic actuating device includes an armature, which has a permanent magnet and can move along a longitudinal axis between actuation positions relative to a stationary coil and in reaction to energization, armature has an engagement section for interacting with a plunger, and which armature can move from a first actuation position, which is stable in the currentless state, into a second actuation position against a restoring force of a spring, wherein the coil has a first coil unit, which acts on the armature and which releases the armature from the first actuation position, wherein the coil has a second coil unit which, during movement, applies to the armature a force which accelerates the armature, and wherein the coil has a restoring coil such that when the armature is returned from the second into the first actuation position, the restoring coil boosts the restoring force of the spring.

Claims

1. An electromagnetic actuating device, which is monostable in the currentless state, comprising an armature unit (12), which has permanent magnetic means (16) and which can move along a movement longitudinal axis (10) between at least two actuation positions relative to stationary coil means (28, 50, 36) and in reaction to energization thereof, which armature unit (12) has an engagement section (26) for interacting with a plunger section (22), which provides an actuation partner and which armature unit (12) can be moved from a first of the actuation positions, which is stable in the currentless state as result of an effect of the permanent magnetic means, into a second of the actuation positions against a restoring force of force storage means (44), wherein the coil means have a first coil unit (28), which is connected or can be connected in order to bring about a force, which acts on the armature unit and which releases the armature unit from the first actuation position, wherein the coil means have a second coil unit (36), which is provided in addition to the first coil unit and is connected or can be connected in such a way that during the movement, the second coil unit applies to the armature unit a force, which accelerates the armature unit, and wherein the coil means have restoring coil means (50, 28, 36), which are embodied and/or connected in such a way that when the armature unit is returned from the second into the first actuation position, said restoring coil means (50, 28, 36) boost the restoring force of the force storage means.

2. The device according to claim 1, wherein the restoring force of the force storage means acting on the armature unit at the second actuation position is greater than a permanent magnetic adhesive force of the permanent magnetic means (16) at the second actuation position.

3. The device according to claim 1, wherein the restoring coil means are realized as additional coil unit (50).

4. The device according to claim 3, wherein the additional coil unit is provided in the area of the second actuation position and/or acts on the armature unit in a restoring manner.

5. The device according to claim 3, wherein the additional coil unit (50) is provided axially adjacent to the second coil unit (36), and/or is provided so as to magnetically interact with a stationary core section (42) assigned to the second coil unit.

6. The device according to claim 5, wherein the additional coil unit (50) is on a joint coil carrier.

7. The device according to claim 1, wherein energizing means are connected upstream or can be connected upstream of the first coil unit and the second coil unit in such a way that, in the case of the armature unit being located in the second actuation position, a continued energization of the first and of the second coil unit takes place, which introduces a lower current, in particular decreased by at least 20%, more preferably by at least 40%, into the first and second coil unit as compared to an energization, which follows during the movement into the second actuation position.

8. The device according to claim 7, wherein the lower current is decreased by at least 20% as compared to the energization which follows during the movement into the second actuation position.

9. The device according to claim 7, wherein the lower current is decreased by at least 40% as compared to the energization which follows during the movement into the second actuation position.

10. The device according to claim 1, wherein the restoring coil means are realized by the first and/or second coil unit and have polarity changing means (60-66), which act on this coil unit(s).

11. The device according to claim 1, wherein the force storage means are realized as compression spring (44) acting on the armature unit in the area of the engagement section.

12. The device according to claim 11, wherein the compression spring engages externally with the armature unit via deflecting means (46) via a tilt lever.

13. The device according to claim 11, wherein the compression spring is integrated in a housing of the electromagnetic actuating device and/or encompasses the plunger section axially adjacent to the permanent magnetic means.

14. A use of the electromagnetic actuating device, which is monostable in the currentless state, according to claim 1, for setting an operating mode of a vehicle unit, wherein the force storage means can establish a defined operating state in the currentless state of the actuating device for moving the armature unit into the first actuation position.

15. The use of claim 14, wherein the vehicle unit is a motorcycle transmission.

16. The device according to claim 1, wherein the force storage means (44) is a spring means.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages, features and details of the invention follow from the description below of preferred exemplary embodiments as well as by means of the drawings;

(2) FIG. 1: shows a longitudinal sectional view of the electromagnetic actuating device according to a first exemplary embodiment of the invention (without spring means);

(3) FIG. 2: shows a main block diagram for energizing the three coil units in the exemplary embodiment of FIG. 1;

(4) FIG. 3: shows, with partial Figures (a) to (c), various alternatives for providing the force storage means according to the invention at the armature unit in the exemplary embodiment of FIG. 1;

(5) FIG. 4: shows a longitudinal sectional view through the electromagnetic actuating device according to a second exemplary embodiment of the invention;

(6) FIG. 5: shows, with partial Figures (a) or (b), respectively, possible schematic circuit diagrams for energizing the two coil units in the exemplary embodiment of FIG. 4 so as to change the polarity, and

(7) FIG. 6: shows, with partial Figures (a) to (c), various alternatives for providing the force storage means according to the invention at the armature unit in the exemplary embodiment of FIG. 4.

(8) In the following discussion of the exemplary embodiments, identical reference numerals signify functional components, which are identical or have the same effect, respectively, in the case of the electromagnetic actuating devices of the respective embodiment.

DETAILED DESCRIPTION

(9) For instance, the longitudinal sectional view of the first embodiment of FIG. 1 thus shows an armature unit 12, which can be moved along a longitudinal axis 10 and which, at a first end, which is directed towards a first core unit 14, has a permanent magnetic disk 16, which is axially defined at both ends by flow guide disks 18, 20. This permanent magnetic unit is followed by an elongated plunger section 22 of the armature unit, which extends along the axial direction in the center of an encompassing cylindrical housing 24, all the way to an open housing end (shown in FIG. 1 on the bottom side), from which an engagement section 26 is then embodiedembodied for interacting with an actuation partner, which is provided here in a motorcycle transmission.

(10) The first stationary core element 14 is enclosed in the manner known for instance from the prior art according to DE 201 14 466 U1 by a first coil unit 28, which has a first winding 30 on a coil support 32 (which is realized, e.g. as plastic injection molded part). On the front side, i.e. at the end of the housing 24 opposite the engagement section 26, it is closed in otherwise known manner in a magnetically fluidically conductive manner in such a way that, in reaction to energization of the first winding 30 (here by means of a schematically shown supply line structure 34), the coil 30 forms an application of force, which repels the permanent magnetic means 26 and which is thus directed downwards along the axial direction in the drawing of FIG. 1. The arrangement is thereby configured in such a way that this repelling effect is (already) sufficient to overcome the permanent magnetic adhesive force of the assembly 16 on the first core 14, so that this movement can take place.

(11) In the context of the shown embodiment, this movement is additionally supported by a second coil unit 36, which has a second winding 38 wound onto a plastic coil support 40. In the case of energization for moving the armature unit from the (first) actuation position of FIG. 1 downstream, this winding 38, supplied via the supply arrangement 34, is also energized in such a way (and it is set up or poled, respectively, in such a way) that the coil 38 exerts a force, which supports the repelling by the first coil unit 28, on the permanent magnetic unit 16, in other words, additionally exerts a pulling action to improve the acceleration and dynamic properties, with corresponding positive impact on a short actuation and movement time of the armature into a second actuation position, which is directed downwards onto a second stationary core 42, wherein this second actuation position, possibly also spaced apart by an armature adhesive disk provided on the armature side, is bounded by a stop formed by the second core 42. The second core unitsurrounding the plunger section 22 on the circumferential side in the shown manner and offering a guide for it to this effecttogether with the second coil 38 as well as a corresponding jacket-side section of the housing 24, forms a magnetic flow circuit, which realizes the described boosting actuating effect of the second coil unit.

(12) The returning of a movement of the armature unit extracted in the described manner (i.e. directed downwards in the direction of a stop at the second core 42) takes place against a restoring force of a spring unit, which is not shown in FIG. 1 and which pretensions the armature unit into an upwards direction (i.e. back into the first actuation position at the first core 14), as shown schematically in connection with FIG. 3 and the partial figures as alternatives (a) to (c): otherwise structurally identical with the longitudinal sectional view of FIG. 1, various options are shown here, how a pressure spring 44 can apply the described restoring force, which is directed in the direction back to the first actuation position, into the armature unit or can then also effect such a restoring in the case of a corresponding compression. For instance, FIG. 3(a) shows a spring element, which is directed onto a front end of the engagement section 26 on the front side, in a schematic manner, the partial figure (b) shows a compression spring across a tilt lever 46 (only shown schematically) as possible alternatives, while, again as alternative (but possibly also when providing two springs additionally) the spring element 44 in the partial image (c) of FIG. 3 is accommodated in the housing interior of the housing 24 in such a way that the pressure spring 44, surrounding the plunger section 22 adjacent to the permanent magnetic unit, is supported at one end on a stop surface of the second core 42 and, at the other end, engages with the flow guide disk 20, which is directed in the direction of the second core.

(13) A spring force or a force behavior of the spring 44, respectively, is thereby set up in such a way that the spring force at the second actuation position (thus at the stop of the armature unit, which is not shown in the Figures, or the permanent magnetic means 16 thereof, respectively, at the second core 42) does not result in a (permanently magnetic) bonding or adhering, respectively, on the core, but this permanently magnetic adhesive force is in fact overcome by means of the above-described restoring force of the spring element 44.

(14) In addition, the first exemplary embodiment of FIGS. 1 to 3 shows a third coil unit 50, which, in the illustrated exemplary embodiment, is provided axially and adjacent in the direction of the first coil unit 28 of the second coil unit 36; in the described exemplary embodiment, the coil support 54, which supports a third coil (winding) of the third coil unit, is also embodied for the module-like assembling, in the alternative in one piece, with the coil support 40 of the second coil unit 36, so that these units are in particular suitable for a compact and potentially automatic manufacturing and assembly.

(15) In the described exemplary embodiment, the third coil 32 is connected or set up in such a way, respectively, that in the case of the described actuating process from the first actuation position (at the core 14) into the second actuation position (at the core 42), the third coil remains non-energized, but the third coil then exerts a restoring force on the armature unit in the direction of the first actuation position in a restoring operationin the case of a non-energized state of the first and of the second coilthus overlaps or boosts, respectively, the restoring force of the restoring spring 44 in this respect.

(16) The circuit diagram of FIG. 2 clarifies such a wiring; the shown switches 56 (for the arrangement of first coil 30 and second coil 38) or 58 (for the third coil 52), respectively, are thereby alternatively closed and thus determine the operating state for moving the armature unit from the first into the second actuation position, when the switch 56 is closed and the switch 58 is open, while the reverse switch state (switch 56 open and switch 58 closed) effects the third coil 52 for returning into the first actuation position, supported by the spring restoring force of the spring unit 44. It becomes clear that the restoring process runs dynamically and in an accelerated manner, in particular also by means of this measure, and that a monostability is thus made possible, which is not disadvantageously influenced by a possible adhesive behavior of the permanent magnet 16 at the second armature, this is in fact compensated by the coil 52.

(17) It becomes clear at the same time that even in the case of no energization, thus also for instance in the case of a power failure state, which is potentially problematic in the prior art, as a result of the still existing restoring effect of the spring 44, a secure and defined returning of the armature unit into the first actuation position (at the first core 14) is ensured, so that it is ensured even in the case of a completely non-energized operating phase that the armature unit 12 is in a defined currentless and rest position (fail safe) with its engagement-side end 26, here in a retracted (upper) operating state of FIG. 1.

(18) The second exemplary embodiment of FIGS. 4 to 6 structurally corresponds almost completely to the first exemplary embodiment of FIGS. 1 to 3, only with the difference that the second exemplary embodiment only has the first coil unit 28 and the second coil unit 36, but not the third additional restoring coil unit 50. An axially shorter and thus potentially more compact device can be realized in this respect. An electromagnetic restoring is nonetheless ensured, as illustrated for instance by the circuit diagrams of FIG. 5(a) or (b), respectively, via the spring-effected restoring of the spring element 44 (the function of the first alternatives of FIGS. 6(a) to (c) is equivalent and analogous to FIGS. 3(a) to (c) of the embodiment in this respect), but it takes place by means of the change of polarity of the interconnected coil pair 30, 38: In the described exemplary embodiment, a switch pair 60, 62 would thereby for instance provide the coils 30 and 38 with an energization of a first polarity, as it is the case for instance for realizing the armature movement, which has already been described in connection with the first exemplary embodiment, from the first actuation position (FIG. 4) into the second actuation position, which is directed downwards at the second core 42. In contrast, the restoring, which supports (the spring 44), would take place by means of a change of polarity of the energization of the coil pair 30, 38 in such a way that the switches 60, 62 are opened in response to this electromagnetically supported restoring, and switches 64, 66 instead apply the energization with the reversed polarity to the coil pair 30, 38. This then has the result that the coil 30 exerts an attracting force on the permanent magnet 16 (changed polarity) and the coil 38 exerts a repelling force on this permanent magnet, with the effect that, overall, a permanently magnetic restoring force, which overlaps the spring restoring force, takes place in the direction of the upper stop at the first core 14. According to FIG. 5(a), it is thereby possible to form a parallel connection of the coils, as well as, in the alternative circuit diagram of FIG. 5(b), to provide it as series connection.

(19) The present invention is not limited to the shown exemplary embodiments, the formation, arrangement and embodiment of the individual coil units is in particular likewise suitable, can be changed or varied, respectively, as the present invention is not limited to the preferred application of a lock for (motorcycle) transmission. In fact, the present invention is suitable for any application, in which, with permanently magnetic armature functionality, dynamic actuating behavior can be combined in both axial actuating directions with monostability in the non-energized state or a defined fail-safe restoring position, respectively.