Magnetization method, component and clutch actuator

Abstract

The present invention relates to a method for magnetizing a component (12) which is rotatable around a rotation axis (100) and is made of a magnetizable material, wherein an excitation magnetic field (26) generated by an excitation unit (22) acts on the component (12) and the excitation magnetic field (26) in a first plane (32) containing the rotation axis (100) rotates around the periphery of the component (12), and the magnetic field gradually weakens each time it rotates around the component (12), thereby generating an annular closed magnetic field (30) in the component (12) in the first plane (32). The present invention also relates to a component (12) manufactured by the method, and a clutch actuator having the component (12) manufactured by the method.

Description

Technical Field

[0001] The invention relates to a method for magnetizing a component according to the generic terminology of claim 1. The invention also relates to a component produced by this method and to a clutch actuator having a component of said type. Background Art

[0002] It is known to use an actuator in a motor vehicle to automatically actuate a clutch. For an automatically actuated clutch, such as an electromagnetic clutch, an actuator is used in conjunction with a manual gearbox.

[0003] One such actuator is the Modular Clutch Actuator, also known as Modular Clutch Actuator, or MCA for short. The modular clutch actuator consists of a rotor and a spindle. The rotor performs a rotational motion that is converted into a linear motion of the spindle by means of a planetary thread rolling, or PWG for short. The linear motion of the spindle results in the actuation of the clutch. Here, the controllable and adjustable actuation of the clutch is achieved by knowledge of the actuation force.

[0004] DE 10 2017 122 171.9 describes an actuator in a clutch actuation system of a motor vehicle, in which the axial actuation force during clutch actuation is measured by a magnetostrictive measuring element.

[0005] DE 10 2017 125 848.5 describes a method for determining magnetostrictive forces on a spindle of a clutch actuator.

[0006] DE 10 2017 123 475.6 describes a bearing for an actuator spindle, the bearing ring of which is magnetized in order to detect the actuating forces acting on the bearing using magnetostrictive detection. Summary of the invention

[0007] The object of the present invention is to provide a method for magnetizing a component.

[0008] At least one of these objects is achieved by a method for magnetizing a component having the features of claim 1. Accordingly, a method for magnetizing a component is proposed, the component being rotatable about a rotation axis and being made of a magnetizable material, wherein an excitation magnetic field generated by an excitation unit acts on the component, and the excitation magnetic field in a first plane containing the rotation axis rotates around the periphery of the component, and the magnetic field gradually weakens with each revolution, thereby generating an annular closed magnetic field in the component in the first plane.

[0009] In this way, an economical and cost-effective magnetization of the component can be achieved, so that axial forces acting on the component can be measured magnetostrictively.

[0010] In particular, the periphery of the component is the outer boundary of the component in the cross section formed by the first plane. For a component that is rotationally symmetrical around the rotation axis and hollow inside, the periphery of the component can be the outer boundary of one of the two halves of the component or the two halves of the component in the cross section formed by the first plane.

[0011] The magnetic field is preferably equidistant from the surface of the component including the periphery.

[0012] In a preferred embodiment of the present invention, the member has a width corresponding to a direction perpendicular to the rotation axis, and the exciting magnetic field has a magnetic field width in the same direction, wherein the magnetic field width is at least as large as the width.

[0013] In a particular embodiment of the present invention, after the component is magnetized in the first plane, an excitation magnetic field in a second plane containing the rotation axis and different from the first plane rotates around the periphery of the component to produce magnetization of the component in the second plane. The component can be rotated around the rotation axis to switch between the first plane and the second plane. Alternatively or additionally, the excitation unit can rotate around the rotation axis.

[0014] The component can be magnetized uniformly with respect to a circumferential direction oriented in the direction of rotation. The magnetic field can be present in all cross sections of the component extending in this circumferential direction.

[0015] In a preferred embodiment of the present invention, the excitation unit is a permanent magnet.

[0016] In a particular embodiment of the invention, the winding is accomplished by movement of the permanent magnet around the periphery of the component in a plane containing the axis of rotation.

[0017] In a preferred embodiment of the present invention, the excitation unit is an electromagnet. The electromagnet may have an electrically conductive coil. In addition, a magnetic flux conducting element, such as an iron magnetic flux conducting element, may be arranged inside the coil.

[0018] In a particular embodiment of the invention, the winding is achieved by moving the electromagnet around the periphery of the member in a plane containing the axis of rotation.

[0019] In an advantageous embodiment of the invention, the excitation unit comprises at least two electromagnets distributed along the periphery of the component. Preferably, the electromagnets are equidistant from each other. More than two electromagnets may be arranged. The electromagnets may be of the same size or of different sizes. The electromagnets may have the same characteristics or different characteristics.

[0020] The winding can be achieved by weakening the excitation magnetic field of the first electromagnet and establishing and strengthening the excitation magnetic field of the second electromagnet. The weakening of the excitation magnetic field of the first electromagnet can be continuous. The establishment and strengthening of the excitation magnetic field of the second electromagnet can be continuous. The strengthening and weakening of the magnetic field can be proportional.

[0021] In addition, a component manufactured using the above method is proposed. The component may be a shaft, a main shaft or a bearing component, such as a bearing ring. The bearing ring may be applied to a bearing of a clutch actuator or a wheel bearing.

[0022] Furthermore, a clutch actuator is proposed, which has a component manufactured by the method described above, wherein the component is a shaft, a spindle and / or a bearing component.

[0023] Further advantages and advantageous embodiments of the invention are apparent from the description of the figures and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention is described in detail below with reference to the accompanying drawings.

[0025] Figure 1 : A three-dimensional cross-sectional view of a clutch actuator in a particular embodiment of the present invention.

[0026] Figure 2 : An arrangement for magnetizing a component configured as a shaft in a special embodiment of the present invention.

[0027] Figure 3 : An arrangement for magnetizing a component configured as a bearing ring in another special embodiment of the present invention.

[0028] Figure 4 : An arrangement for magnetizing a component configured as a shaft in another particular embodiment of the present invention.

[0029] Figure 5 : An arrangement for magnetizing a component configured as a bearing ring in another special embodiment of the present invention. DETAILED DESCRIPTION

[0030] Figure 1 A three-dimensional cross-sectional view of a clutch actuator 10 in a particular embodiment of the invention is shown. The clutch actuator 10 comprises an electric motor with a stator 11 and a rotor 13. The rotor 13 can convert the rotational motion of a component into a linear motion of a component 12 by means of planetary thread rolling. The component 12 is a spindle 14. The clutch actuator 10 also comprises a ball bearing 16 with another component 12, here a bearing component, for example an outer bearing ring 18.

[0031] The main shaft 14 and the components connected thereto realize clutch actuation through linear motion. Wherein, the main shaft 14 is subjected to an axial force, such as a clutch actuation force. This axial force can also act on the bearing ring 18.

[0032] In order to reliably operate or control the clutch actuation, it is necessary to know this axial force. Among them, magnetostrictive measurement of the axial force has proven to be particularly advantageous.

[0033] The axial force causes an axial deformation of the corresponding component 12. If the component 12 has been magnetized, the magnetostrictive effect can be used to measure the axial load. Accurate magnetization of the component is essential for reliable measurement of the axial load.

[0034] It has been found that the component should preferably have a circular, closed magnetic field positioned in a first plane to best detect axial loads by the magnetostrictive effect.

[0035] Figure 2 An arrangement for magnetizing a component 12 configured as a shaft in a particular embodiment of the invention is shown. The shaft 20 is rotatable about an axis of rotation 100 and is made of a magnetizable material.

[0036] The excitation unit 22 designed as a permanent magnet 24 here generates an excitation magnetic field 26 acting on the shaft 20. In order to magnetize the shaft with a continuous magnetic field 30 that is annularly closed and equidistant from the component surface 28 of the component 12, the excitation magnetic field 26 is guided by the movement of the permanent magnet 24 in a first plane 32 including the rotation axis 100 so that the excitation magnetic field rotates around the periphery of the component 12. The permanent magnet 24 moves further away from the shaft 20 with each turn, so that the excitation magnetic field 26 acting on the component 12 becomes weaker and weaker, and the magnetic field 30 is continuously applied to the component 12.

[0037] The shaft 20 has a width 34 corresponding to a direction perpendicular to the rotation axis 100 , and the excitation magnetic field 26 has a magnetic field width 36 in the same direction, wherein the magnetic field width 36 is at least as large as the width 34 .

[0038] Figure 3 The arrangement for magnetizing a component 12 configured as a bearing component in a special embodiment of the present invention is shown. The bearing component 38 is, for example, a bearing ring 40 here. The magnetization of the bearing ring 40 is achieved by the excitation unit 22, which is designed as a permanent magnet 24 here, generating an excitation magnetic field 26 that acts on the bearing ring 40.

[0039] In order to magnetize the bearing ring 40 having the continuous magnetic field 30 which is located in the first plane 32, is annularly closed, and is equidistant from the component surface 28 of the component 12, the excitation magnetic field 26 is guided by the movement of the permanent magnet 24 in the first plane 32 including the rotation axis 100, so that the excitation magnetic field rotates around the periphery of the component 12. The permanent magnet 24 moves further and further away from the bearing ring 40 with each revolution, whereby the excitation magnetic field 26 acting on the component 12 becomes weaker and weaker, and thus the magnetic field 30 is continuously applied to the bearing ring 40.

[0040] In order to magnetize the bearing ring 40 around the entire component surface 28 and thus also in the inner region 42, the permanent magnet 24 is passed through the inner region 42 of the bearing ring 40. Alternatively, the bearing ring 40 can be designed to be split, whereby a rotation with the permanent magnet 24 can be realized more easily.

[0041] Figure 4 In another particular embodiment of the invention, an arrangement for magnetizing a component 12 designed as a shaft is shown.

[0042] The excitation unit 22 is an electromagnet 44 which is arranged circumferentially around the component surface 28 in a plane 32 including the rotation axis 100. The electromagnet 44 is composed of a plurality of individual electromagnets 44, each of which has an electrically charged coil 46. In addition, a magnetic flux conducting element, such as an iron magnetic flux conducting element, may be arranged in the coil 46.

[0043] The winding is performed by weakening the excitation magnetic field 26 of the first electromagnet 48 and building up and amplifying the excitation magnetic field 26 of the adjacent second electromagnet 50 so that the shaft 20 is magnetized with a closed and continuous magnetic field 30 equidistant from the component surface 28 .

[0044] The weakening of the excitation magnetic field 26 of the first electromagnet 48 continues. The building up and amplification of the excitation magnetic field 26 of the second electromagnet 50 continues and is proportional to the weakening of the excitation magnetic field 26 of the first electromagnet 48 .

[0045] The individual electromagnets 44 are arranged equidistantly from one another so that the orbits on the component surface 28 are uniform and thus the magnetization is uniform.

[0046] Figure 5 In another special embodiment of the invention, an arrangement for magnetizing a component 12 designed as a bearing ring is shown.

[0047] The excitation unit 22 is an electromagnet 44 which is arranged circumferentially around the component surface 28 in a plane 32 including the rotation axis 100. The electromagnet 44 is composed of a plurality of individual electromagnets 44, each of which has an electrically charged coil 46. In addition, a magnetic flux conducting element, such as an iron magnetic flux conducting element, may be arranged in the coil 46.

[0048] By weakening the excitation magnetic field 26 of a first electromagnet 48 and building up and amplifying the excitation magnetic field 26 of an adjacent second electromagnet 50 , the winding is performed so that the bearing ring 40 is magnetized with a closed and continuous magnetic field 30 equidistant from the component surface 28 .

[0049] The weakening of the excitation magnetic field 26 of the first electromagnet 48 continues. The building up and amplification of the excitation magnetic field 26 of the second electromagnet 50 continues and is proportional to the weakening of the excitation magnetic field 26 of the first electromagnet 48 .

[0050] The individual electromagnets 44 are arranged equidistantly from one another so that the orbits on the component surface 28 are uniform and thus the magnetization is uniform.

[0051] In order to magnetize the bearing ring 40 around the entire component surface 28 and therefore also in its inner region 42, electromagnets 44 are also arranged in the inner region. The size of the individual electromagnets does not necessarily have to be the same. It is also possible to arrange smaller electromagnets 44 in the inner region than in the adjacent regions. However, the size of the excitation magnetic field generated by the electromagnets 44 arranged in the inner region 42 can still be equal to the excitation magnetic field of the electromagnets 44 arranged in the adjacent regions. For example, the electromagnets arranged in the inner region 42 can be operated with a larger current. Alternatively, the bearing ring 40 can be designed to be separate, thereby making it easier to arrange the electromagnets 44.

[0052] After magnetizing component 12 in first plane 32 , excitation magnetic field 26 may rotate around the periphery of component 12 in a second plane that includes rotation axis 100 and is different from first plane 32 , thereby also inducing magnetization of component 12 in the second plane.

[0053] Thus, the component 12 can be rotated around the rotation axis 100 to switch between the first plane 32 and the second plane. Alternatively or additionally, the excitation unit 22 can be rotated around the rotation axis 100. If there is a non-uniformly distributed local axial load in the rotation direction of the component 12 and this load should be collected by magnetostriction, it is very advantageous to magnetize in two or more such planes.

[0054] Description of Reference Numerals

[0055] 10 Clutch actuator

[0056] 11. Stator

[0057] 12 Components

[0058] 13 Rotor

[0059] 14 Spindle

[0060] 16 Ball bearings

[0061] 18 Bearing ring

[0062] 20 Axis

[0063] 22 Excitation unit

[0064] 24 permanent magnets

[0065] 26 Excitation magnetic field

[0066] 28 Component surface

[0067] 30 Magnetic Field

[0068] 32 Plane

[0069] 34 Width

[0070] 36 Magnetic field width

[0071] 38 Bearing components

[0072] 40 Bearing ring

[0073] 42 Internal Area

[0074] 44 Electromagnet

[0075] 46 Coil

[0076] 48 Electromagnet

[0077] 50 Electromagnet

[0078] 100 Rotation axis

Claims

1. A method for magnetizing a component (12), the component being rotatable about a rotation axis (100) and being made of a magnetizable material, wherein: The excitation magnetic field (26) generated by the excitation unit (22) acts on the component (12). It is characterized in that The excitation magnetic field (26) surrounds the periphery of the component (12) in a first plane (32) including the rotation axis (100) and weakens with each circle, thereby generating an annular closed magnetic field (30) in the component (12) within the first plane (32).

2. The method for magnetizing a component (12) according to claim 1, characterized in that The member (12) has a width (34) corresponding to a direction perpendicular to the rotation axis (100), and the excitation magnetic field (26) has a magnetic field width (36) in the same direction, wherein the magnetic field width (36) is the same size as the width (34).

3. The method for magnetizing a component (12) according to claim 1 or 2, characterized in that: After magnetizing the component (12) in a first plane (32), an excitation magnetic field (26) surrounds the periphery of the component (12) in a second plane including the rotation axis (100) and different from the first plane (32), thereby completing magnetization of the component (12) in the second plane.

4. The method for magnetizing a component (12) according to claim 1 or 2, characterized in that: The excitation unit (22) is a permanent magnet (24).

5. The method for magnetizing a component (12) according to claim 4, characterized in that: The wrapping is achieved by movement of the permanent magnet (24) around the periphery of the component (12) in a plane including the axis of rotation (100).

6. The method for magnetizing a component (12) according to claim 1 or 2, characterized in that: The excitation unit (22) is an electromagnet (44).

7. The method for magnetizing a component (12) according to claim 6, characterized in that: The encirclement is achieved by movement of the electromagnet (44) around the periphery of the component (12) in a plane (32) including the axis of rotation (100).

8. The method for magnetizing a component (12) according to claim 7, characterized in that: The excitation unit (22) includes at least two electromagnets (44) arranged along the periphery of the component (12).

9. A component (12) produced by the method according to one of the preceding claims, wherein: The component is a shaft or a bearing component.

10. A clutch actuator (10) having a component (12) manufactured by a method according to any one of claims 1 to 8, wherein: The component (12) is a shaft or a bearing component.

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