Electromagnetic actuator

Abstract

The present invention relates to an electromagnetic actuating device comprising a coil with a coil axis, a magnetizable yoke having a groove arranged around the coil axis and in which the coil is at least partially arranged, and a magnetizable armature movable toward the yoke from a released position to an attracted position by a magnetic field generated by the coil in an actuation direction parallel to the coil axis. According to the invention, the yoke has an outer yoke pole face and an inner yoke pole face, and the armature has an outer armature pole face and an inner armature pole face.

Description

[0001] The present invention relates to an electrical actuating device according to the preamble of independent claim 1.

[0002] A generic electromagnetic actuating device comprises a coil with a coil axis, a magnetizable yoke having a groove arranged around the coil axis and in which the coil is at least partially arranged, and a magnetizable armature which can be moved towards the yoke from a released position to an attracted position by a magnetic field generated by the coil in an actuating direction parallel to the coil axis.

[0003] Such known actuating devices often have the problem that the attraction force of the coil in combination with the yoke against the armature in the actuating direction is insufficient relative to the size of the actuating device.

[0004] It is an object of the present invention to provide an improved electrical actuating device of the generic type which enables an improved tightening force in relation to the size of the actuating device.

[0005] The problem is solved by the features of independent claim 1. Accordingly, in an electrical actuating device according to the preamble of independent claim 1, the problem is solved according to the invention if the yoke has an outer yoke pole surface which is arranged outside the coil and is designed at least in regions as a segment of a truncated cone surface, wherein a base surface of the segment of the truncated cone surface is designed as an elliptical sector, preferably as a circular sector, with a central angle of at least 45°, preferably of at least 90°, more preferably of at least 180°, particularly preferably of 360°, a conical axis of the segment of the truncated cone surface runs parallel to the coil axis, and surface lines of the segment of the truncated cone surface have a curvature not equal to or equal to 0 in a plane,spanned by the cone axis of the segment of the truncated cone surface and a reference point of the surface line of the segment of the truncated cone surface on the base surface of the segment of the truncated cone surface, and having an inner yoke pole surface which is arranged within the coil and which is formed at least in regions as a segment of an inverted truncated cone surface, wherein a base surface of the segment of the inverted truncated cone surface is formed as an elliptical sector, preferably as a circular sector, with a central angle of at least 45°, preferably of at least 90°, more preferably of at least 180°, particularly preferably of 360°, a cone axis of the segment of the inverted truncated cone surface runs parallel to the coil axis, and surface lines of the segment of the inverted truncated cone surface have a curvature not equal to or equal to 0 in a plane,spanned by the cone axis of the segment of the inverted truncated cone surface and a reference point of the generatrix of the segment of the inverted truncated cone surface on the base surface of the segment of the inverted truncated cone surface, wherein the groove is arranged between the outer yoke pole surface and the inner yoke pole surface and the armature has an outer armature pole surface which is designed such that a constant distance in the actuation direction results between the outer yoke pole surface and the outer armature pole surface, and an inner armature pole surface which is designed such that a constant distance in the actuation direction results between the inner yoke pole surface and the inner armature pole surface.

[0006] The inventive solution offers the advantage that the design of the pole faces of the yoke and the armature allows the distance between the yoke and the armature to be reduced, and the inner and outer pole faces create a large effective pole area, thereby increasing the attractive force relative to the size. Furthermore, the increased attractive force eliminates the need for an economy circuit.

[0007] The curvature of the generatrix of the segment of the truncated cone surface of the outer yoke pole surface is designed such that the radial distance between the generatrix of the segment of the truncated cone surface and the cone axis of the segment of the truncated cone surface decreases continuously in the opposite direction of actuation. In addition, the curvature of the generatrix of the segment of the inverted truncated cone surface of the inner yoke pole surface is designed such that the radial distance between the generatrix of the segment of the inverted truncated cone surface and the cone axis of the segment of the inverted truncated cone surface decreases continuously in the opposite direction of actuation.

[0008] Advantageous embodiments of the present invention are the subject of the subclaims.

[0009] In a particularly preferred embodiment of the present invention, the outer yoke pole face surrounds the coil perpendicular to the coil axis by 360°, with the outer armature pole face surrounding the coil perpendicular to the coil axis by at least 270°. This utilizes the entire circumference of the coil, resulting in a large outer yoke pole face relative to the required size of the yoke. The same applies to the outer armature pole face or the armature. Depending on the design of an electrical connection to the coil, the outer armature pole face can also surround the coil perpendicular to the coil axis by 360°.

[0010] In a further preferred embodiment of the present invention, the inner yoke pole surface surrounds the coil axis perpendicular to the coil axis by 360°, while the inner armature pole surface surrounds the coil axis perpendicular to the coil axis by 360°. This results in a large inner yoke pole surface and inner armature pole surface relative to the size of the armature and yoke.

[0011] In a particularly preferred embodiment of the present invention, the outer yoke pole surface is designed as a straight circular truncated cone surface. Such an outer yoke pole surface is efficient to manufacture and enables a very compact design of the actuator.

[0012] In another preferred embodiment, the outer yoke pole surface has two segments of a straight circular truncated cone surface, wherein a respective base surface of the segments of the straight circular truncated cone surface is formed as a circular sector with a central angle of 180°, a respective cone axis of the segments of the straight circular truncated cone surface runs parallel to the coil axis, and the two segments are connected to one another by two, preferably non-curved, connecting surfaces at their respective end surface lines. Such an outer yoke pole surface can also be manufactured efficiently and enables a compact design of the actuating device. By varying the distance between the two segments, the attractive force can be precisely adjusted, and the actuating device can be arranged in compact, elongated housings.

[0013] In a further preferred embodiment of the present invention, the inner yoke pole surface is designed as an inverted straight circular truncated cone surface or has two segments of an inverted straight circular truncated cone surface, wherein a respective base surface of the segments of the inverted straight circular truncated cone surface is designed as a circular sector with a central angle of 180°, a respective cone axis of the segments of the inverted straight circular truncated cone surface runs parallel to the coil axis, and the two segments are connected to one another by two, preferably non-curved, connecting surfaces at their respective end surface lines. This also enables efficient production and a high attraction force due to the inner pole surfaces relative to the size of the actuating device.

[0014] According to a preferred embodiment of the invention, angles between normals on the outer yoke pole surface and the actuating direction are between 90° and 180°, preferably between 100° and 135°, particularly preferably between 105° and 125°. These angles result in advantageous tightening force characteristics relative to the size of the actuating device. At the same time, the tightening force characteristic can be precisely adjusted as needed by adjusting the angles. Preferably, the angles between the normals on the outer yoke pole surface and the actuating direction are a constant value between 90° and 180°, preferably between 100° and 135°, particularly preferably 105°. Using a constant value simplifies production.

[0015] According to a further preferred embodiment of the invention, angles between normals on the inner yoke pole surface and the actuating direction are between 90° and 180°, preferably between 100° and 135°, particularly preferably between 105° and 125°. At these angles, advantageous tightening force characteristics are obtained relative to the size of the actuating device. At the same time, the tightening force characteristic can be precisely adjusted by adjusting the angles as required. Preferably, the angles between the normals on the inner yoke pole surface and the actuating direction are a constant value between 90° and 180°, preferably between 100° and 135°, particularly preferably 110.5°. Using a constant value simplifies production.

[0016] In a particularly preferred embodiment of the present invention, it is provided that the yoke has a yoke stop pole face which is oriented at right angles to the actuation direction and is arranged either between the outer yoke pole face and the groove or the inner yoke pole face and the groove, and the armature has an armature stop pole face which is designed such that a constant distance in the actuation direction results between the yoke stop pole face and the armature stop pole face, wherein the armature and the yoke are designed such that the armature and the yoke, in the attracted position of the armature, only touch via the yoke stop pole face and the armature stop pole face and an outer residual air gap, which is preferably between 0.05 and 0.2 mm, in the actuation direction between the outer yoke pole face and the outer armature pole face and an inner residual air gap, which is preferably between 0.05 and 0.2 mm,in the actuation direction between the inner yoke pole face and the inner armature pole face. This improves the switching behavior of the actuator and reduces residual effects.

[0017] In a preferred embodiment, the groove is open toward the armature opposite to the actuation direction, with the coil projecting beyond the groove and, at least in the engaged position, into a groove in the armature. Preferably, in the engaged position, at least 15° of the coil's axial extension projects into the groove in the armature. This enables a simple and very compact design of the actuating device.

[0018] In another particularly preferred embodiment, the coil is arranged in an electrically non-conductive coil carrier, wherein the coil and the coil carrier are arranged and configured relative to the yoke and the armature in such a way that there is no direct contact between the coil and the yoke and armature. In an advantageous embodiment, the coil carrier is formed from a cylinder and two flanges adjoining the ends of the cylinder. This enables a simple construction of the coil carrier. At the same time, the flanges can be used to attach additional components, such as the electrical connection to the coil.

[0019] According to a preferred embodiment, the coil carrier has at least one, preferably two, return spring receptacles arranged such that a return spring inserted therein exerts a force on the armature counter to the actuation direction when the armature is in the attracted position. This makes it possible to generate a restoring force in a compact manner, which moves the armature from the attracted position to the open position when the coil is no longer energized. Preferably, the return spring receptacle is arranged on the collar of the advantageous embodiment of the coil carrier. This enables a simple construction of the coil carrier. Further preferably, the armature has a cavity into which the return spring receptacle with the return spring enters when the armature is moved into the attracted position. This allows the actuating device to be designed even more compactly.Preferably, the cavity is formed by a bore in the armature, wherein an exit hole of the bore is closed with a welded sheet metal opposite to the actuation direction in order to form the cavity.

[0020] According to a further preferred embodiment, two first auxiliary contacts are arranged on the coil carrier such that a first conductive element, which is attached to the armature or formed by a portion of the armature, electrically connects the two first auxiliary contacts when the armature is moved into the attracted position and electrically disconnects them when the armature is moved out of the attracted position. Preferably, the two first auxiliary contacts are located on a collar of the advantageous coil carrier design that is oriented opposite to the actuation direction. This allows for a space-saving determination of whether the armature is in the attracted position.

[0021] In a further preferred embodiment, two second auxiliary contacts are arranged on the coil carrier such that a second conductive element, which preferably also forms the first conductive element, which is attached to the armature or is formed by a portion of the armature, electrically connects the two second auxiliary contacts when the armature is moved into the released position and electrically disconnects them when the armature is moved out of the released position. This allows for a space-saving determination of whether the armature is in the released position.

[0022] According to a particularly preferred embodiment, a shock protection device comprising a permanent magnet wound with a control coil is attached to the coil carrier in such a way that the permanent magnet is in contact with the armature when the armature is in the released position and holds it in the released position as long as the control coil is not energized in such a way that a magnetic field of the control coil balances a magnetic field of the permanent magnet. This can prevent the armature from being deflected from the released position to the attracted position due to impacts and the like.

[0023] According to a particularly preferred embodiment, the yoke has a continuous bearing bore in the actuation direction, which is aligned parallel, preferably coaxially, to the coil axis and in which a projection of the armature is guided in and against the actuation direction. A plain bearing bush is preferably arranged in the bearing bore, which guides the projection. This guides the armature relative to the yoke. Accordingly, a switching rod can also be attached to the projection of the armature, which is deflected by the movement of the armature in and against the actuation direction.

[0024] Preferably, the armature has a through-bore in the actuation direction, which is aligned parallel, preferably coaxially, to the coil axis and extends through the projection, so that the switching rod can be inserted into the through-bore, and the position of the switching rod in the through-bore can be fixed to the armature by welding the switching rod to an edge of the through-bore. This allows the position of the switching rod relative to the armature and thus also to the yoke to be flexibly adjusted.

[0025] In a further preferred embodiment of the present invention, the yoke and the armature are made of steel and copper in a ratio of 2:1 to 4:1, preferably a ratio of 7:3 to 10:3, particularly preferably in a ratio of 2.6:1. This achieves a high tightening force relative to the size of the actuating device.

[0026] Embodiments of the present invention are explained in more detail below with reference to drawings.

[0027] They show: Fig. 1a, b oblique views of a first embodiment of an electromagnetic actuating device according to the invention in the released position and the tightened position, Fig. 2a, b Sections through the first embodiment in the two positions shown in Fig. 1a and Fig. 1b, where the section plane contains the coil axis, Fig. 3a, b, c, d views on sectional planes through yokes according to the invention, Fig. 4a, b oblique views of a second embodiment of an electromagnetic actuating device according to the invention in the released position and the tightened position, Fig. 5 Exploded view of the second embodiment, Fig. 6 Oblique view of the second embodiment without the anchor, Fig. 7a, b Sections through the second embodiment in the two positions shown in Fig. 4a and Fig. 4b, where the cutting plane contains the coil axis and intersects the return springs, Fig. 8a, b Sections through the second embodiment in the two positions shown in Fig. 4a and Fig. 4b, where the cutting plane runs parallel to the coil axis and intersects the first auxiliary contacts, Fig. 9 Oblique view from below of a third embodiment of an electromagnetic actuating device according to the invention in the released position, Fig. 10a, b sections through the fourth embodiment in the released position and the tightened position, wherein the section plane contains the coil axis, Fig. 11a, b Oblique views from above and below of a fourth embodiment of an electromagnetic actuating device according to the invention in the released position Fig. 12a, b Detailed view of sections through the third embodiment in the released position and the tightened position, wherein the cutting plane runs parallel to the coil axis and intersects the first and second auxiliary contacts, and Fig. 13 View from below of a section through the first embodiment, wherein the adjusting device additionally comprises a switching rod and the sectional plane contains the coil axis.

[0028] In the following explanations, identical parts are designated by identical reference numerals. Where a figure contains reference numerals that are not further explained in the corresponding figure description, reference is made to preceding or subsequent figure descriptions.

[0029] The Fig. 1 and Fig. 2 show a first embodiment of an electromagnetic actuating device 1 according to the invention in the released position, shown in Fig. 1a and Fig. 2a, or the tightened position shown in Fig. 1b and Fig. 2b.

[0030] The first embodiment of the electromagnetic actuating device 1 according to the invention comprises a coil 2 with a coil axis 3, a magnetizable yoke 4 having a groove 5 arranged around the coil axis 3 and in which the coil 2 is at least partially arranged, and a magnetizable armature 6. The armature 6 is moved towards the yoke 4 from the released position into the attracted position by a magnetic field that can be generated by the coil 2 in an actuation direction 7 parallel to the coil axis 3.

[0031] The yoke 4 has an outer yoke pole surface 8, which is arranged outside the coil 2 and is designed as a segment of a truncated cone surface, wherein a base surface of the segment of the truncated cone surface is designed as a circular sector with a central angle of 360°, a cone axis of the segment of the truncated cone surface runs parallel and coaxially to the coil axis 3 and surface lines 9 of the segment of the truncated cone surface have a curvature equal to 0 in a plane spanned by the cone axis of the segment of the truncated cone surface and a reference point of the surface line of the segment of the truncated cone surface on the base surface of the segment of the truncated cone surface and shown in Fig. 2. The angles between normals on the outer yoke pole surface 8 and the actuating direction 7 are a constant value of 105° in this first embodiment.

[0032] In addition, the yoke 4 has an inner yoke pole surface 10 which is arranged within the coil 2 and which is designed as a segment of an inverted truncated cone surface, wherein a base surface of the segment of the inverted truncated cone surface is designed as a circular sector with a central angle of 360°, a cone axis of the segment of the inverted truncated cone surface runs parallel and coaxially to the coil axis 3 and surface lines 11 of the segment of the inverted truncated cone surface have a curvature equal to 0 in a plane spanned by the cone axis of the segment of the inverted truncated cone surface and a reference point of the surface line 11 of the segment of the inverted truncated cone surface on the base surface of the segment of the inverted truncated cone surface and shown in Fig. 2. The angle between the normal on the inner yoke pole surface 10 and the actuating direction 7 is a constant value of 110.5° in this first embodiment. The groove 5 is arranged between the outer yoke pole surface 8 and the inner yoke pole surface 10.

[0033] The armature 6 has an outer armature pole face 12, which is designed such that a constant distance in the actuation direction 7 results between the outer yoke pole face 8 and the outer armature pole face 12. In the first exemplary embodiment, the outer armature pole face 12 is designed as a segment of an inverted truncated cone surface, wherein a base surface of the segment of the inverted truncated cone surface is designed as a circular sector with a central angle of 240° and a cone axis of the segment of the inverted truncated cone surface runs parallel and coaxial with the coil axis 3. The lower central angle of the segment forming the outer armature pole face 12 compared to the central angle of the segment forming the outer yoke pole face 8 results from the fact that the armature 6 has a recess via which the coil terminal 13 is attached to the coil carrier 14, onto which the coil 2 is wound.In addition, the armature 6 has an inner armature pole face 15, which is designed such that a constant distance results in the actuation direction 7 between the inner yoke pole face 10 and the inner armature pole face 15. In the first exemplary embodiment, the inner armature pole face 15 is designed as a segment of a truncated cone surface, wherein a base surface of the segment of the truncated cone surface is designed as a circular sector with a central angle of 360° and a conical axis of the segment of the truncated cone surface runs parallel and coaxial to the coil axis 3.

[0034] Furthermore, the yoke 4 has a yoke stop pole face 16 which is aligned at right angles to the actuating direction 7 and is arranged between the inner yoke pole face 10 and the groove 5, wherein the armature 6 has an armature stop pole face 17 which is designed such that a constant distance in the actuating direction 7 results between the yoke stop pole face 16 and the armature stop pole face 17. The armature 6 and the yoke 4 are designed such that the armature 6 and the yoke 4 in the attracted position of the armature 6 only touch via the yoke stop pole face 16 and the armature stop pole face 17 and an outer residual air gap 18 in the actuation direction 7 between the outer yoke pole face 8 and the outer armature pole face 12 and an inner residual air gap 19 in the actuation direction between the inner yoke pole face 10 and the inner armature pole face 15 remains in the attracted position of the armature 6.

[0035] As mentioned above, the coil 2 is wound on a coil carrier 14, which is cylindrical and has a collar in and against the actuation direction 7. The coil 2 with the coil carrier 14 is partially arranged in the groove 5 in the yoke 4 and projects beyond the groove 5 and into a groove 20 in the armature 6, counter to the actuation direction 7.

[0036] The Fig. Figure 3 shows sectional views through yokes 4 according to the invention, wherein the sectional plane contains the coil axis 3. The yokes 4 shown here have an outer yoke pole surface 8, which is formed as a segment of a truncated cone surface, wherein the base surface of the segment of the truncated cone surface is formed as a circular sector with a central angle of 360°, a cone axis of the segment of the truncated cone surface runs parallel and coaxially to the coil axis 3, and surface lines 9 of the segment of the truncated cone surface have a curvature equal to or not equal to 0 in a plane spanned by the cone axis of the segment of the truncated cone surface and a reference point of the surface line of the segment of the truncated cone surface on the base surface of the segment of the truncated cone surface, and an inner yoke pole surface 10, which is formed as a segment of an inverted truncated cone surface.wherein a base surface of the segment of the inverted truncated cone surface is formed as a circular sector with a central angle of 360°, a cone axis of the segment of the inverted truncated cone surface runs parallel and coaxial with the coil axis 3, and surface lines 11 of the segment of the inverted truncated cone surface have a curvature not equal to or equal to 0 in a plane spanned by the cone axis of the segment of the inverted truncated cone surface and a reference point of the surface line of the segment of the inverted truncated cone surface on the base surface of the segment of the inverted truncated cone surface.

[0037] The Fig. 4 shows a second embodiment of an electromagnetic actuating device 1 according to the invention in the released position, shown in Fig. 4a, and the tightened position shown in Fig. 4b. The second embodiment of the actuating device 1 differs from the first embodiment in particular by the design of the outer yoke pole surface 8 and, accordingly, the outer armature pole surface 12.

[0038] The outer yoke pole surface 8 of the second embodiment has two segments of a straight circular truncated cone surface, wherein a respective base surface of the segments of the straight circular truncated cone surface is formed as a circular sector with a central angle of 180°, a respective cone axis of the segments of the straight circular truncated cone surface runs parallel to the coil axis 3, and the two segments are connected to one another by two connecting surfaces at their respective end surface lines. As a result, the yoke 4 and the armature 6 are extended in length in a direction perpendicular to the coil axis 3 compared to the first embodiment.

[0039] Fig. 5 shows the second embodiment of the adjusting device 1 in an exploded view. Fig. 6 shows the second embodiment of the adjusting device 1 without armature 6 and from below.

[0040] The coil carrier 14 is, as in the first embodiment of the actuating device 1, designed as a cylinder, each with a collar 21, 22 in and against the actuation direction 7, wherein the coil 2 is wound onto the cylinder. On the collar 22, opposite the actuation direction 7, two return spring receptacles 23 are arranged, offset by 180°, in each of which a return spring 24 is located. The return spring receptacles 23 and return springs 24 are arranged in such a way that they exert a force on the armature opposite the actuation direction, which force is greatest as soon as the armature is in the attracted position. For this purpose, the armature has two bores 35 in the armature, which are welded by means of metal sheets, into which the return spring receptacles 23 and the return springs 24 are inserted when the armature is transferred from the released position to the attracted position. This procedure is evident from the Fig. 7a and Fig. 7b.

[0041] The Fig. 8a, Fig. 8b: In addition, there are two first auxiliary contacts 25 on the collar 22 opposite to the actuation direction 7 of the coil carrier 14, which are accessible via the coil connection 13. Due to the arrangement of the two first auxiliary contacts 25 on the collar 22 opposite to the actuation direction 7, the two first auxiliary contacts 25 come into contact with a base surface of the groove 20 in the armature 6 when the latter is in the attracted position. This results in a conductive connection between the first auxiliary contacts 25, which can be detected by means of a measuring device, whereby it can be detected that the armature 6 is in the attracted position. This procedure is evident from the Fig. 8a and Fig. 8b can be seen.

[0042] The Fig. 9 and Fig. 10 show a third embodiment of an actuating device 1 according to the invention. This differs from the second embodiment of the actuating device 1 in that a shock protection device is attached to the collar 22 opposite to the actuation direction 8. This has a permanent magnet 26, around which a control coil 27 is wound, and is fastened to the coil carrier 14 in such a way that the permanent magnet 26 is in contact with the armature 6 when the armature 6 is in the released position and holds it in the released position as long as the control coil 27 is not energized in such a way that a magnetic field of the control coil 27 compensates for a magnetic field of the permanent magnet 26. This procedure is evident from the Fig. 10a and Fig. 10b can be seen.

[0043] The Fig. 11 and Fig. 12 show a fourth exemplary embodiment of an actuating device 1 according to the invention. The outer yoke pole surface 8 and outer armature pole surface 12 are designed as a straight circular truncated cone surface or an inverted straight circular truncated cone surface, and the coil connection is made via a recess in the armature 6, which does not penetrate the armature in the actuation direction. As in the second exemplary embodiment, two first auxiliary contacts 25 are attached to the coil carrier 14 of the fourth exemplary embodiment. In addition, however, the coil carrier 14 has two second auxiliary contacts 28 which are offset from the first auxiliary contacts 25 opposite the attraction direction 7 such that a conductive element 29, which is fastened to the armature 6, conductively connects the second auxiliary contacts 28 to one another in the released position of the armature 6 and conductively connects the first auxiliary contacts 25 in the attracted position of the armature 6.This allows the first auxiliary contacts 25 and second auxiliary contacts 28 to detect the current position of the armature 6. Furthermore, the first auxiliary contacts 25 and the second auxiliary contacts 28 can have the same potential, thus providing redundancy in the contact area and increasing the safety and availability for armature position determination.

[0044] Fig.13 shows a view from below of a section through the first embodiment, wherein the actuating device 1 additionally comprises a switching rod 30 and the sectional plane contains the coil axis 3. The figure shows how the yoke 4 has a through-bearing bore 31 in the actuation direction 7, which is aligned coaxially to the coil axis 3 and in which a projection 32 of the armature 6 is guided in and against the actuation direction 7. A plain bearing bush 33 is arranged in the bearing bore 31 and guides the projection 32. Such a bearing of the armature 6 relative to the yoke 4 is also included in the second, third and fourth embodiments of the actuating device 1.The armature 6 also has a through-bore 34 in the actuation direction 7, which is also aligned coaxially with the coil axis 3 and extends through the projection 32, so that the switching rod 30 can be inserted into the through-bore 34 and the position of the switching rod 30 in the through-bore 34 can be attached to the armature 6 by welding the switching rod 30 to an edge of the through-bore 34. This allows the post-stroke to be adjusted automatically during production. List of reference symbols 1 Electromagnetic actuator 2 coils 3 coil axis 4 yoke 5 grooves 6 anchors 7 Actuating direction 8 Outer yoke pole surface 9 Mantle line 10 Inner yoke pole surface 11 Mantle line 12 Outer armature pole face 13 Coil connection 14 coil carriers 15 Inner armature pole face 16 Yoke stop pole face 17 Armature stop pole face 18 Outer residual air gap 19 Internal residual air gap 20 grooves 21, 22 fret 23 Return spring holder 24 Return spring 25 First aid contact 26 permanent magnet 27 Control coil 28 Second auxiliary contact 29 Conductive element 30 shift rod 31 bearing bore 32 lead 33 plain bearing bush 34 Through hole 35 bore

Claims

[1] Electromagnetic actuating device with a coil having a coil axis, a magnetizable yoke having a groove arranged around the coil axis and in which the coil is at least partially arranged, and a magnetizable armature which is movable by a magnetic field generated by the coil in an actuating direction parallel to the coil axis from a released position to an attracted position towards the yoke, characterized bythat the yoke has an outer yoke pole surface which is arranged outside the coil and is formed at least in regions as a segment of a truncated cone surface, wherein a base surface of the segment of the truncated cone surface is formed as an elliptical sector, preferably as a circular sector, with a central angle of at least 45°, preferably of at least 90°, more preferably of at least 180°, particularly preferably of 360°, a cone axis of the segment of the truncated cone surface runs parallel to the coil axis and surface lines of the segment of the truncated cone surface have a curvature not equal to or equal to 0 in a plane spanned by the cone axis of the segment of the truncated cone surface and a reference point of the surface line of the segment of the truncated cone surface on the base surface of the segment of the truncated cone surface, and an inner yoke pole surface,which is arranged within the coil and which is formed at least in regions as a segment of an inverted truncated cone surface, wherein a base surface of the segment of the inverted truncated cone surface is formed as an elliptical sector, preferably as a circular sector, with a central angle of at least 45°, preferably of at least 90°, more preferably of at least 180°, particularly preferably of 360°, a conical axis of the segment of the inverted truncated cone surface runs parallel to the coil axis, and surface lines of the segment of the inverted truncated cone surface have a curvature not equal to or equal to 0 in a plane spanned by the conical axis of the segment of the inverted truncated cone surface and a reference point of the surface line of the segment of the inverted truncated cone surface on the base surface of the segment of the inverted truncated cone surface,wherein the groove is arranged between the outer yoke pole surface and the inner yoke pole surface, and the armature has an outer armature pole surface which is designed such that a constant distance in the actuating direction results between the outer yoke pole surface and the outer armature pole surface, and an inner armature pole surface which is designed such that a constant distance in the actuating direction results between the inner yoke pole surface and the inner armature pole surface. [2] Electromagnetic actuator according to claim 1, characterized by that the outer yoke pole surface surrounds the coil perpendicular to the coil axis by 360°, whereby the outer armature pole surface surrounds the coil perpendicular to the coil axis by at least 270°. [3] Electromagnetic actuator according to claim 1 or 2, characterized bythat the inner yoke pole surface surrounds the coil axis perpendicular to the coil axis by 360°, whereby the inner armature pole surface surrounds the coil axis perpendicular to the coil axis by at least 270°. [4] Electromagnetic actuator according to one of claims 1 to 3, characterized by that the outer yoke pole surface is designed as a straight circular truncated cone surface or has two segments of a straight circular truncated cone surface, wherein a respective base surface of the segments of the straight circular truncated cone surface is designed as a circular sector with a central angle of 180°, a respective cone axis of the segments of the straight circular truncated cone surface runs parallel to the coil axis and the two segments are connected to one another by two, preferably non-curved, connecting surfaces at their respective end surface lines. [5] Electromagnetic actuator according to one of claims 1 to 4, characterized bythat the inner yoke pole surface is designed as an inverted straight circular truncated cone surface or has two segments of an inverted straight circular truncated cone surface, wherein a respective base surface of the segments of the inverted straight circular truncated cone surface is designed as a circular sector with a central angle of 180°, a respective cone axis of the segments of the inverted straight circular truncated cone surface runs parallel to the coil axis and the two segments are connected to one another by two, preferably non-curved, connecting surfaces at their respective end surface lines. [6] Electromagnetic actuator according to one of claims 1 to 5, characterized bythat angles between normals on the outer yoke pole surface and the actuating direction are between 90° and 180°, preferably between 100° and 135°, particularly preferably between 105° and 125°, wherein the angles between the normals on the outer yoke pole surface and the actuating direction preferably have a constant value between 90° and 180°, preferably between 100° and 135°, particularly preferably 105°. [7] Electromagnetic actuator according to one of claims 1 to 6, characterized by that angles between normals on the inner yoke pole surface and the actuating direction are between 90° and 180°, preferably between 100° and 135°, particularly preferably between 105° and 125°, wherein the angles between the normals on the inner yoke pole surface and the actuating direction preferably have a constant value between 90° and 180°, preferably between 100° and 135°, particularly preferably 110.5°. [8] Electromagnetic actuator according to one of claims 1 to 7, characterized bythat the yoke has a yoke stop pole face that is oriented at right angles to the actuation direction and is arranged either between the outer yoke pole face and the groove or the inner yoke pole face and the groove, and the armature has an armature stop pole face that is designed such that a constant distance in the actuation direction results between the yoke stop pole face and the armature stop pole face, wherein the armature and the yoke are designed such that the armature and the yoke, in the attracted position of the armature, only touch via the yoke stop pole face and the armature stop pole face, and an outer residual air gap, which is preferably between 0.05 mm and 0.2 mm, in the actuation direction between the outer yoke pole face and the outer armature pole face and an inner residual air gap, which is preferably between 0.05 mm and 0.2 mm,in the actuating direction between the inner yoke pole face and the inner armature pole face remains., [9] Electromagnetic actuator according to one of claims 1 to 8, characterized by that the groove is open towards the armature opposite to the actuating direction, wherein the coil projects beyond the groove and, at least in the attracted position, projects into a groove in the armature, wherein preferably in the attracted position at least 15° of an axial extension of the coil projects into the groove in the armature. [10] Electromagnetic actuator according to one of claims 1 to 9, characterized by that the coil is arranged in an electrically non-conductive coil carrier, which is preferably formed from a cylinder and two collars adjoining the ends of the cylinder, wherein the coil with the coil carrier is arranged and formed relative to the yoke and the armature in such a way that there is no direct contact between the coil and the yoke and armature. [11] Electromagnetic actuator according to claim 10, characterized by that the coil carrier has at least one, preferably two, return spring receptacles which are arranged in such a way that a return spring inserted therein exerts a force on the armature opposite to the actuating direction when the armature is in the attracted position. [12] Electromagnetic actuator according to claim 10 or 11, characterized by that two first auxiliary contacts are arranged on the coil carrier in such a way that a first conductive element which is fastened to the armature or is formed by a portion of the armature electrically connects the two first auxiliary contacts when the armature is brought into the attracted position and electrically separates them when the armature is brought out of the attracted position. [13] Electromagnetic actuator according to one of claims 10 to 12, characterized bythat two second auxiliary contacts are arranged on the coil carrier in such a way that a second conductive element, which preferably also forms the first conductive element, which is fastened to the armature or is formed by a portion of the armature, electrically connects the two second auxiliary contacts when the armature is brought into the released position and electrically separates them when the armature is brought out of the released position. [14] Electromagnetic actuator according to one of claims 10 to 13, characterized by that a shock protection device with a permanent magnet wound with a control coil is attached to the coil carrier in such a way that the permanent magnet is in contact with the armature when the armature is in the released position and holds it in the released position as long as the control coil is not energized in such a way that a magnetic field of the control coil balances a magnetic field of the permanent magnet. [15] Electromagnetic actuator according to one of claims 1 to 14, characterized by that the yoke and the armature are made of steel and copper in a ratio of 2:1 to 4:1, preferably a ratio of 7:3 to 10:3, particularly preferably in a ratio of 2.6:1.

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