ELECTROMAGNETIC ACTUATOR DEVICE AND USE OF SUCH A DEVICE

Abstract

An electromagnetic actuator includes an armature (18) movable axially relative to a stationary core (14) as a reaction to energizing of a stationary coil (12) in an actuator housing (10). The armature (18) is gripped by an axially extended slide (20) guided in a core passage (50) of the core such that a movement of the armature in the direction of the core entrains the slide. An end section (26) of the slide, axially opposite the armature, cooperates with an adjusting partner, the slide having a long rod section (34) and a disk-type end section (30) with a widened diameter on the rod section, on the end in the direction of the armature (18), the axial extension (W) of the end section. determining a minimum distance between the armature and the core in an abutment state of the armature on an end surface and/or front surface of the core, facing the armature.

Claims

1. An electromagnetic actuator device having armature means (18) which, as a reaction to stationary coil means (12) being energized, is movable in an actuator housing (10) along an axial direction relative to stationary core means (14), and which are gripped by axially elongated plunger means (20) guided in a core passage (50) of the core means in such a manner that a movement of the armature means in the direction of the core means can entrain the plunger means, an end section (26) of the plunger means, axially opposite the armature means, being realized for interacting with or realizing a control partner wherein the plunger means comprise an elongated rod section (34) and a disk-shaped end section (30) having a widened diameter and the end section (30) sitting on the rod section as one piece on the end side in the direction of the armature means (18), the axial extension (W) of the end section determining a minimum distance between the armature means and the core means in an abutment state of the armature means on an end surface and/or front surface of the core means facing the armature means.

2. The device according to claim 1, wherein the plunger means (20) are made of a polymer material using an injection molding process.

3. The device according to claim 1, wherein the rod section has a recess on the shell side which is realized as a longitudinal groove (36, 38) in such a manner that a medium pressure equalization can be realized between an armature space (50) which is realized by the armature means and the core means and an actuation area which is opposite to the core means in the axial direction.

4. The device according to claim 1, wherein the disk-shaped end section has a profiling (42, 44) on a flat side, said profiling being provided for interacting with the end surface or front surface of the core means.

5. The device according to claim 4, wherein the profiling is realized as at least one groove (42, 44).

6. The device according to claim 1, wherein the armature means have an armature passage (32) which extends in the axial direction and wherein the plunger means are realized for gripping, at least in sections, an opening on the plunger side of the armature passage in the area of the disk-shaped end section.

7. The device according to claim 6, wherein the plunger means have a plunger passage (52, 54) through the disk-shaped end section (30), in such a manner that the plunger passage opens the armature passage (32) towards an armature space (50) between the armature means and the core means while equalizing the medium pressure when the armature means are gripped by the plunger means.

8. The device according to claim 1, wherein the rod section (34) has a preferably circumferential guide surface (46, 48) formed in one piece in sections in the axial direction for the sliding interaction with a guide inner surface of the core passage (50), said guide surface (46, 48) projecting in the radial direction on the sleeve side.

9. The device according to claim 1, wherein energy storing mean are assigned in a frictional manner to the armature means and/or to the plunger means in such a manner that said energy storing means pre-stress the armature means in an axial abutment position away from the core means in the valve housing.

10. A use of the electromagnetic actuator device according to claim 1 as a proportional valve device and/or as a camshaft control valve for an internal combustion engine.

11. The device according to claim 1, wherein the control partner is a valve slide (28).

12. The device according to claim 1, wherein the end section is in the form of a magnetic anti-adhesive disk.

13. The device according to claim 2, wherein the polymer material has a glass fiber blending.

14. The device according to claim 3, wherein the longitudinal groove (36, 38) is continuous in the axial direction.

15. The device according to claim 5, wherein the at least one groove (42, 44) extends perpendicularly to the axial direction in the flat side.

16. The device according to claim 6, wherein the armature passage (32) is in an axial central bore.

17. The device according to claim 6, wherein the armature means has an annular step (50).

18. The device according to claim 7, wherein the plunger passage (52, 54) is a bore.

19. The device according to claim 9, wherein the energy storing means is in the form of spring means.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Further advantages, features and details of the invention can be derived from the following description of preferred exemplary embodiments and from the drawings.

[0020] In the following,

[0021] FIG. 1 is a partially sectional lateral view of the electromagnetic actuator device according to a first exemplary embodiment of the invention;

[0022] FIG. 2 to FIG. 7 are different views of the plunger means used within the scope of the actuator device of FIG. 1 and

[0023] FIG. 8 is a longitudinal sectional, schematic view for clarifying a generic electromagnetic actuator device as background of the invention.

DETAILED DESCRIPTION

[0024] In the partially sectional view of FIG. 1, functionally equivalent assemblies compared to those of FIG. 8 are referenced with the same reference signs; a winding 12 on a coil support acts as a (stationary) coil mean comprising a hollow-cylindrical or sleeve-like stationary core 14 which interacts with an armature body 18 along the axial direction (horizontal in the drawing layer of FIG. 1), a conus section 15 of the core interacting with an armature projection 19 (in a manner known per se and for realizing a magnetic force-air gap) on the side of the armature. The disposition of core assembly 14 and armature assembly 18 is surrounded by an armature guide tube 21 (typically made of a non-magnetic steel material) which is directly located in the coil support of coil means 12. Coil means 12 are located in a substantially cylindrical housing shell 10, a plug section 11 being led out said housing shell 10 for an external energization of coil 12. Reference sign 17 refers to a seal 17 which supports (and seals) core unit (core means) 14 in armature guide tube 21.

[0025] A front surface on the end side of an end section 26 of plunger means 20 grips an assigned front surface on the engagement side of a valve slide unit 28 (as a control partner) axially opposite armature 18, a widened end section 30 of the plunger means sitting on end section 19 on the core side of armature means 18 on the other end. Said means have an armature bore 32 as an armature passage which extends through the armature means in the axial direction, disk-shaped end section 30 extending to an opening of said bore 32 when it contacts the armature means (shown in FIG. 1).

[0026] Plunger assembly 20 (plunger means) of the shown exemplary embodiment is produced by means of injection molding from a glass fiber reinforced (GF) polyamide material—PPS having 40 wt.-% GF in the present case. More precisely, plunger assembly 20 which is realized in one piece is composed of disk-shaped end section 30 (realized for a detachable sitting on core assembly 18) which passes to a rod section 34. Said rod section 34 has a pair of opposite longitudinal grooves 36, 38 which extend along a sleeve side in the axial direction and which connect an armature space 40 which is limited between core means 14 and armature means 18 (and which can be adjusted according to the armature position) in a pressure-equalizing manner to an engagement area on the right side of end section 26 (in the direction of valve slide 28).

[0027] It is shown how the effective (axial) width w (FIG. 4) of disk 30, in the form of an anti-adhesive disk, defines a minimum distance between armature 18 and core 14, a reliable fall and retransfer of the armature unit into the initial position of FIG. 1 thus being ensured when the energization of coil 12 is stopped (this is made possible by a return spring (not shown) by analogy with pressure spring 22 in FIG. 8 which engages at valve slide 28 as a control partner).

[0028] Additionally and preferably, disk-shaped end section 30 of plunger means 20 has means for avoiding a sticking (hydrostatic, because of an oil film or the like) of unit 20 to core 14 in the form of a pair of parallel longitudinal grooves 22, 44 (which extend perpendicular to the axial direction); in particular shown grooves 42, 44 reduce such an undesired adhesive effect in an advantageous manner and facilitate the detachment of the plunger means from the core when it is retransferred.

[0029] Additionally and preferably, rod section 34 of plunger means 20 has a pair of circumferential areal annular projections 46, 48 which are formed in one piece and which—as radial projections—allows for sliding surfaces for guiding plunger means 20 in hollow-cylindrical inner bore 50 of the core means (core passage).

[0030] Furthermore, the end surface of disk-shaped end section 30 which is directed at armature means 18 is provided with a circumferential annular step 50, in particular shown in FIG. 2 and FIG. 7, end section 30 thus sitting on the outer edge on the front side of armature means 18 and realizing a step, said outer edge being realized by end section 19, and end section 30 opening or releasing armature bore 32 to armature space 50 via a pair of passages 52, 54 which is realized in end section 30—in a corresponding manner, a pressure equalization can be realized which extends to the end (on the left side in FIG. 1) of armature means 18 in armature guide tube 21.

[0031] If an injection tool for the production of plunger means 20 is realized in a suitable manner, all the abovementioned embodiments, grooves, projections and passages can be manufactured using a single manufacturing step—the injection molding—, in particular without the need for additional manufacturing steps for realizing individual functional sections. Accordingly, plunger assembly 20 is suitable for combining a cost-efficient production and large-scale manufacturability with a wide range of applications (also within the scope of configurable modular systems or the like).