Assembly comprising shaft, magnet and plastic part

Abstract

The invention relates to an assembly (10) for a motor vehicle. The assembly (10) comprises a shaft (2) rotatable about a longitudinal axis, and a magnet (3) disposed near one end of the shaft (1). The magnet (3) has an anisotropic direction (X) perpendicular to the longitudinal axis. The magnet (3) has at least one main flat surface (5) or at least one main concave surface (5a) extending at least partially along the longitudinal axis. The assembly (10) further comprises a plastic part (2) overmolded on the shaft (1) and the magnet (3). At least one tangent of the at least one primary flat surface (5), or of the at least one primary concave surface (5a), is parallel to the anisotropy direction (X) and is at least partially free of the plastic part (2) for indicating the orientation of the anisotropy direction (X).

Description

TECHNICAL FIELD

[0001] The subject matter of the present invention relates to an assembly comprising a rotating shaft, a magnet and a plastic part. The assembly is particularly used in actuators for automotive applications. BACKGROUND

[0002] Generally, actuators are used in automotive for various applications. Such actuators can be a park lock actuator, a gear shift actuator, an electronic throttle controller, etc. These actuators are assemblies that generally comprise a rotating shaft, a magnet mounted on the shaft, and a rotary position sensor. Generally, the magnet is mounted on a distal end of the shaft. The magnet operates as a target for the rotary position sensor. The rotary position sensor, or sensor, is arranged in close proximity to the magnet such that the sensor detects a magnetic field generated by the magnet. As a result, information related to the angular position of the shaft can be determined. Generally, the rotary position sensor is a Hall effect angular position sensor, or any such sensor.

[0003] In a known manner, the magnet is overmoulded in plastic before being mounted on the shaft. The magnet is magnetized after overmoulding such that the high temperature applied during overmoulding does not cancel the anisotropic magnetic properties of the magnet. However, there is a risk that the magnet is not optimally oriented for overmoulding, and thus, during magnetization, the magnet can not be magnetized according to the correct direction. Therefore, a magnet that has been magnetized in an incorrect manner can have a shorter lifetime in terms of operating as a target in an actuator.

[0004] Therefore, there is a need to address the technical problems associated with the above-described typical actuator assembly. SUMMARY

[0005] It is therefore an object of the present arrangement to provide an assembly that overcomes the above-mentioned and other drawbacks of known arrangements and that provides for precisely orienting a magnet in the correct magnetization direction.

[0006] The present arrangement relates to an assembly comprising a shaft rotatable about a longitudinal axis, a magnet provided in the vicinity of one end of the shaft, the magnet having an anisotropy direction perpendicular to the longitudinal axis of the shaft, the magnet having at least one main flat surface or at least one main concave surface extending at least partially along the longitudinal axis, a plastic part overmoulding the shaft and the magnet, at least one tangent of the at least one main flat surface or the at least one main concave surface being parallel to the anisotropy direction of the magnet and at least partially free of the plastic part for indicating the orientation of the anisotropy direction.

[0007] Therefore, the mounting position of the magnet with respect to the molded part and plastic component is facilitated by the at least one main flat surface or the at least one main recessed surface of the magnet, and it helps to align the magnet with the magnetizer core for magnetization after overmolding with the plastic component. The at least one main flat surface or the at least one main recessed surface of the magnet facilitates precise orientation and magnetization according to the desired anisotropic direction of the magnet.

[0008] According to the present invention, the magnet is formed in a disk shape. This shape allows for a strong magnetic field, rather than a ring shape which has a weaker magnetic field due to the lack of material in the center.

[0009] According to the present invention, a plastic component is overmolded onto the peripheral surface of the magnet. This ensures better radial magnet fixation.

[0010] According to the invention, the at least one main flat surface or the at least one main recessed surface is located on the periphery of the magnet. This provides easy access to the overmolding and magnetizing tools.

[0011] According to one aspect of this arrangement, the magnet has at least one secondary flat surface or at least one secondary recessed surface extending at least partially along a longitudinal axis, and at least one tangent of the at least one secondary flat surface or the at least one secondary recessed surface is parallel to the anisotropic direction of the magnet and is at least partially overmolded with a plastic component. Therefore, by means of the secondary flat surface or secondary recessed surface of the magnet and by overmolding with a plastic component, the magnet can be optimally oriented by means of a tool.

[0012] According to another aspect of this arrangement, the at least one primary flat surface and the at least one secondary flat surface are opposite to each other, or the at least one primary recessed surface and the at least one secondary recessed surface are opposite to each other. Therefore, during magnetization, a magnetic field collinear with the anisotropic direction is achieved.

[0013] According to another aspect of this arrangement, the magnet has a cylindrical shape with a diameter of D and extends along the longitudinal axis with a height of H.

[0014] According to another aspect of this arrangement, the distance A between the at least one primary flat surface and the at least one secondary flat surface is between 0.7 and 0.9 times the diameter D of the magnet.

[0015] According to another aspect of the device, the height H of the magnet is between 0.3 times the actual diameter D of the magnet and the actual diameter D.

[0016] According to another aspect of this arrangement, the width W of the at least one primary flat surface and the at least one secondary flat surface is determined by the width Provided.

[0017] Therefore, a magnet with a cylindrical shape including a flat surface avoids linear errors in the signal angle of the sensor element, which measures the axial field of the magnet and provides a perfect sinusoidal shape of the magnetic field.

[0018] According to another aspect of this arrangement, the magnet has a parallelepiped shape. Therefore, magnets with a parallelepiped shape are more robust in terms of magnetic aging because they have a high permeability.

[0019] According to another aspect of this arrangement, the plastic component is a gear, sector gear, or rotor. Therefore, the plastic component, as a gear, sector gear, or rotor, not only covers the molded shaft and magnet, but is also capable of transmitting torque between the shaft and adjacent components.

[0020] According to another aspect of this arrangement, this subject matter relates to an angular position sensing system comprising components configured according to this arrangement, wherein a sensor is placed in front of a magnet. The sensor detects a magnetic field, thereby sensing the angular position of an axis to which the magnet is attached.

[0021] According to another arrangement, this subject matter relates to an electromechanical actuator or rotating machine for automotive applications, which includes an angular position sensing system according to this arrangement.

[0022] In another aspect, this subject matter relates to a method for manufacturing an assembly having a shaft, a magnet, and plastic components, the method comprising the following steps:

[0023] (a) Provide a ferromagnetic material having at least one primary flat surface or at least one primary recessed surface and at least one secondary flat surface or at least one secondary recessed surface extending at least partially along a longitudinal axis, wherein at least one tangent of the at least one primary flat surface or the at least one primary recessed surface of the ferromagnetic material is aligned parallel to the anisotropic direction of the ferromagnetic material.

[0024] (b) A ferromagnetic material is deposited in a molded part near one end of a shaft using a tool, wherein the anisotropic direction is perpendicular to the longitudinal axis of the shaft, wherein the tool holds at least one of the secondary flat surfaces or at least one of the secondary recessed surfaces of the ferromagnetic material, and the molded part receives at least partially the at least one of the primary flat surfaces or the primary recessed surfaces of the ferromagnetic material.

[0025] (c) Remove the tool and mold the shaft and the ferromagnetic material by covering them with the plastic component, wherein at least one of the at least flat secondary surface or the at least one recessed secondary surface is at least partially covered by the plastic component;

[0026] (d) The ferromagnetic material is magnetized by placing it in a magnetic field. Therefore, the mounting position of the magnet with the molded part and plastic component is facilitated by means of the at least one main flat surface or the at least one main recessed surface of the magnet, and it helps to align the magnet with the magnetizer core for magnetization after overmolding with the plastic component. The at least one main flat surface or the at least one main recessed surface of the magnet facilitates precise orientation and magnetization according to the desired anisotropic direction of the ferromagnetic material. Attached Figure Description

[0027] The following description and accompanying drawings will provide a better understanding of this arrangement. The components in the drawings are not necessarily drawn to scale; rather, the focus is on illustrating the principles of the arrangement. Furthermore, in the drawings, the same reference numerals denote corresponding parts. In the drawings:

[0028] Figure 1 A top view of an embodiment of the components configured according to this topic is shown;

[0029] Figure 2 and Figure 2a A perspective view of the magnets in the components configured according to this topic is shown;

[0030] Figure 2b and Figure 2c A top view of an embodiment of a magnet according to this subject is shown;

[0031] Figure 3 A perspective view of the components, including the shaft and magnet, configured according to this topic is shown;

[0032] Figure 4 A perspective sectional view of the components arranged according to this subject is shown, wherein the plastic parts are sector gears and are overmolded onto the shaft and magnet;

[0033] Figure 5 A front view of an angular position sensing system including components configured according to this topic is shown;

[0034] Figure 6 The various stages of magnet formation configured according to embodiments of this subject are shown; and;

[0035] Figure 7 It is a flowchart depicting the assembly process of magnets arranged according to the layout of this topic.

[0036] The accompanying drawings are not necessarily drawn to scale, and the dimensions of some parts may be exaggerated to more clearly illustrate the examples shown. Furthermore, the drawings provide examples and / or examples consistent with the description; however, the description is not limited to the examples and / or instances provided in the drawings. Detailed Implementation

[0037] In the following description, reference is made to the accompanying drawings, which form a part of the description, and specific embodiments in which the invention can be practiced are illustrated by way of illustration. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it should be understood that these embodiments may be combined, or other embodiments may be utilized, and structural and logical changes may be made without departing from the scope of the invention. Therefore, the following detailed description should not be considered limiting, and the scope of the invention is defined by the appended claims and their equivalents.

[0038] Figure 1 A top view of an assembly 10 configured according to this subject matter is shown, the assembly 10 including a shaft 1, a magnet 3, a molded part, and a plastic component 2. The shaft 1 is configured to rotate about a longitudinal axis. The magnet 3 is disposed near one end of the shaft 1 in an anisotropic direction X perpendicular to the longitudinal axis of the shaft 1. The magnet 3 has at least one main flat surface 5 extending at least partially along the longitudinal axis. The plastic component 2 is molded over the shaft 1 and partially molded over the magnet 3, thereby holding the magnet 3 in place on the shaft 1. The plastic component 2 is molded over the peripheral surface of the magnet 3. The shaft 1 and the plastic component 2 are two distinct elements of the assembly 10. The at least one main flat surface 5 is parallel to the anisotropic direction X of the magnet 3 and is at least partially absent from the plastic component 2. Therefore, the at least one main flat surface 5 without the plastic component 2 indicates the anisotropic direction X of the magnet 3 and facilitates the precise orientation and magnetization of the magnet 3 according to its anisotropic direction X.

[0039] According to one aspect of this subject matter, the magnet 3 includes at least one sub-flat surface 6 extending at least partially along a longitudinal axis 4. The at least one sub-flat surface 6 is parallel to the anisotropic direction X of the magnet 3 and is at least partially molded within a plastic component 2. Furthermore, the molded component includes finger structures 20a, 20b, and 20c, which facilitate receiving and holding the magnet 3 in place.

[0040] exist Figure 1 In the example shown, the magnet 3 is formed in a cylindrical shape 7 and extends at least partially along the longitudinal axis. Figure 1The magnet 3 in the molding comprises a primary flat surface 5 and a secondary flat surface 6, which are opposite to each other. The molding receives the magnet 3 via three finger structures 20a, 20b, and 20c spaced 120° apart. One of the finger structures 20a of the molding is a flat surface 17 that at least partially abuts the primary flat surface 5, thus limiting the relative rotation of the magnet 3 before or during the overmolding process. The other two finger structures 20b and 20c of the molding have curved surfaces (by means of cylindrical shapes 18 and 19) adjacent to cylindrical shapes 7, which are complementary to the curved regions of the molding. Therefore, the magnet 3 is held and indexed within the molding.

[0041] According to another embodiment of this subject matter, the magnet 3 includes at least one main recessed surface and a secondary recessed surface extending at least partially along the longitudinal axis of the shaft 1.

[0042] according to Figure 1 In the example shown, plastic component 2 partially covers shaft 1 and partially covers magnet 3. Plastic component 2 holds magnet 3 such that sub-flat surface 6 is at least partially molded through plastic component 2. Plastic component 2 has a flat surface 14 that at least partially abuts sub-flat surface 6, thus limiting relative rotation of magnet 3 within plastic component 2 during operation of assembly 10. The orientation direction (magnetization direction) is readily apparent from the main flat surface 5 of plastic component 2. Plastic component 2 also has two finger-like structures with curved surfaces abutting cylindrical shapes 7 (due to cylindrical shapes 15, 16), which are complementary to the cylindrical shape 7 of magnet 3. Therefore, the mounting position of magnet 3 is held and indexed within plastic component 2.

[0043] Figure 2 A perspective view of magnet 3 configured according to this topic is shown. Figure 2a A perspective view of magnet 3 configured according to this topic is shown. Figure 2b A top view of a magnet 3 configured according to an embodiment of this subject is shown. For brevity, the magnet 3 is described together with the magnet 3 in this document. Figure 2 , Figure 2a , Figure 2bThe magnet 3 is formed in a cylindrical shape 7 and has a longitudinal axis 4 perpendicular to the anisotropic direction X. Preferably, the diameter D of the cylinder 7 is between 4 mm and 14 mm. It is also preferred that the height H of the magnet 3 is between 0.3 times and the actual diameter D of the magnet 3, with the height H along the longitudinal axis 4. As explained in the preceding description, the primary flat surface 5 and the secondary flat surface 6 are formed such that both surfaces 5 and 6 are parallel to the anisotropic direction X of the magnet 3 and are opposite to each other. In the example shown, the distance A between the primary flat surface 5 and the secondary flat surface 6 is configured at any position between 0.7 times and 0.9 times the diameter D of the magnet 3. The width W of the primary flat surface 5 and the width W of the secondary flat surface 6 are determined by the width... Provided.

[0044] Magnet 3 is radially magnetized. In an exemplary embodiment, magnet 3 may be a rare-earth magnet, such as neodymium iron boron (sintered) with a nickel coating or potentially anisotropic hard ferrite. Preferably, the flatness tolerance of the at least one primary flat surface 5 and the at least one secondary flat surface 6 is between 10% and 15% of the height H of magnet 3. Furthermore, magnet 3 having a cylindrical shape 7 avoids linear errors in the signal angle of the sensor element, which measures the axial field of magnet 3 and provides a perfect sinusoidal shape of the magnetic field.

[0045] In an exemplary embodiment, the magnet 3 is formed into a parallelepiped shape having a primary flat surface and a secondary flat surface, and the primary flat surface and the secondary flat surface are parallel to the anisotropic direction X of the magnet 3 and opposite to each other. Preferably, the distance between the primary flat surface and the secondary flat surface is between 5 mm and 5.6 mm.

[0046] In such Figure 2c In the exemplary embodiment shown, the magnet 3 includes a cylindrical shape 7 extending along a longitudinal axis 4, and includes a primary recessed surface 5a and a secondary recessed surface 6a. At least one tangent of the primary recessed surface 5a is parallel to the anisotropic direction X of the magnet 3. A tangent of the secondary recessed surface 6a is parallel to the anisotropic direction X of the magnet 3. The magnet 3 is formed in a disk shape.

[0047] In another embodiment, the plastic component 2 is overmolded onto the shaft 1 and partially overmolded onto the magnet 3, thereby holding the magnet 3 in place on the shaft 1. The at least one tangent of the primary recessed surface 5a is parallel to the anisotropic direction X of the magnet 3 and is at least partially absent from the plastic component 2. Therefore, the primary recessed surface 5a without the plastic component 2 indicates the anisotropic direction X of the magnet 3 and facilitates the precise orientation and magnetization of the magnet 3 according to its anisotropic direction X. Further according to the subject matter, the magnet 3 includes a secondary recessed surface 6a extending at least partially along the longitudinal axis 4. The at least one tangent of the secondary recessed surface 6a is parallel to the anisotropic direction X of the magnet 3 and is at least partially overmolded into the plastic component 2. Therefore, the primary recessed surface 5a adjacent to the molded component helps to limit the relative movement of the magnet 3 within the molded component before or during the overmolding process. In a similar manner, the recessed surface 6a adjacent to the plastic component 2 helps to limit the relative movement of the magnet 3 within the plastic component 2 during operation of the assembly 10.

[0048] In another embodiment, the magnet 3 is formed as a parallelepiped shape having a main recessed surface and a secondary recessed surface. At least one tangent of the main recessed surface is parallel to the anisotropic direction X of the magnet 3. At least one tangent of the secondary recessed surface is parallel to the anisotropic direction X of the magnet 3.

[0049] In another embodiment, the primary and secondary surfaces may have profiles that do not conform to the flat surface. The profiles may be cross-sectional profiles as seen from a top view. For example, in a non-limiting manner, the profiles that do not conform to the flat surface of the magnet 3 may have raised and lowered portions. In a non-limiting manner, the profiles of the raised and lowered portions may resemble a stepped or zigzag pattern.

[0050] Figure 3 A perspective view of assembly 10, including shaft 1 and magnet 3, is shown. Assembly 10 is configured according to this subject matter. (The remaining text is not shown.) Figure 1 The plastic component 2 shown is a shaft 1 with a circular cross-section. The shaft 1 extends along a longitudinal axis 4 and is used to transmit power, torque, or rotational motion between two components of a machine, or to transmit power, torque, or rotational motion from a torque-generating machine to a torque-absorbing machine. A magnet 3 is disposed near one end of the shaft 1 in an anisotropic direction X perpendicular to the longitudinal axis 4 of the shaft 1. The outer periphery of the shaft 1 includes at least one groove 1a, which helps to hold the overmolded plastic component 2. The shaft 1 is formed of metal.

[0051] Figure 4 A perspective cross-sectional view of component 10, configured according to an example of this topic, is shown. Figure 4As shown, the plastic component 2 is a sector gear 2a, and is partially molded over the shaft 1 and the magnet 3. The sector gear 2a is a segment of a gear that extends within any angular range between 0° and 360°, preferably between 0° and 90°, while the gear can extend to the entire 360°. The sector gear 2a is similar to a gear, but has teeth 2b on its outer periphery for a finite segment and a smooth remainder. In another arrangement, the sector gear 2a may have more than one finite segment on its outer periphery, for example, two opposing segments. The sector gear 2a rotates about the longitudinal axis 4 around which the shaft 1 rotates, and the shaft 1 is typically seen in actuators that require a finite number of repetitive rotations about the longitudinal axis 4. The shaft 1, the plastic component 2, and the magnet 3 are arranged coaxially about the longitudinal axis 4. The magnet 3 has a primary flat surface 5 and a secondary flat surface 6, which are parallel to the anisotropy direction X of the magnet 3 and opposite to each other. The secondary flat surface 6 is molded with a plastic component 2, while the primary flat surface 5 is without the plastic component 2 and is visible. Therefore, the orientation direction (magnetization direction) for magnetizing the magnet 3 can be clearly determined at a glance.

[0052] In one example, the plastic component 2 is preferably a gear. In yet another example, the plastic component 2 is preferably a rotor, which, in a non-limiting manner, can be a plastic rotor containing magnetic particles or magnets. The gear or rotor is overmolded onto a shaft 1 and a magnet 3 configured according to the subject matter.

[0053] In another embodiment, the magnet 3 is indirectly coupled to the shaft 1. Specifically, in the above embodiment, a metal insert is inserted between the shaft 1 and the magnet 3 to facilitate the aforementioned coupling. The plastic component 2 is at least partially molded over the magnet 3 and at least partially molded over the metal insert.

[0054] Figure 5A front view of an angular position sensing system 21 configured according to this subject matter is shown. The angular position sensing system 21 includes a component 10 configured according to this subject matter. Component 10 includes a shaft 1, a magnet 3, a sensor 22, and a plastic component 2. The magnet 3 has at least one main flat surface 5 or at least one main recessed surface 5a extending at least partially along a longitudinal axis 4. The plastic component 2 is overmolded onto the shaft 1 and the magnet 3, characterized in that at least one tangent of the at least one main flat surface 5 or the at least one main recessed surface 5a is parallel to the anisotropic direction X of the magnet 3, and at least partially lacks the plastic component 2 for indicating the orientation of the anisotropic direction X. In one example, the sensor 22 is, for example, a Hall effect sensor or a magnetoresistive sensor (MR sensor). Both sensors detect the generated magnetic field, with the Hall sensor sensing the polarity of the magnetic field and the MR sensor sensing the angular position of the magnetic field. Both types of sensors are often used together because their operating modes are complementary.

[0055] Figure 6 The process of manufacturing an embodiment of the magnet 3 configured according to this subject matter is shown. Figure 6 In the example shown, the magnet 3 is manufactured using a material removal process, such as milling or shaping. Preferably, the raw material used is a ferromagnetic material 23 in the form of a rectangular bar having a width 24 and lengths 25 and 26. The width 24 of the ferromagnetic material 23 is transformed into a cylindrical shape 7. Then, the lengths 25 and 26 of the ferromagnetic material 23 are surface-machined to form the at least one primary flat surface 5 and the at least one secondary flat surface 6.

[0056] Figure 7 This is a flowchart illustrating the steps and assembly process for manufacturing a magnet according to the present subject matter. In step 71, a raw material, ferromagnetic material 23, is provided. In one example, the magnet 3 is manufactured from the ferromagnetic material 23 by a material removal process in a non-limiting manner as described above. Thus, as in step 72, the manufactured magnet 3 has at least one primary flat surface 5 or at least one primary recessed surface 5a and at least one secondary flat surface 6 or at least one secondary recessed surface 6a, which extend at least partially along the longitudinal axis 4, and at least one tangent of the at least one primary flat surface 5 or the at least one primary recessed surface 5a of the ferromagnetic material 23 is aligned parallel to the anisotropic direction X of the ferromagnetic material 23.

[0057] Further, as in step 73, deposition of ferromagnetic material 23 in the molded part is performed. Ferromagnetic material 23 is deposited in the molded part near one end of shaft 1 using a tool, its anisotropic direction X being perpendicular to the longitudinal axis 4 of shaft 1, wherein the tool holds at least one of the secondary flat surfaces 6 or at least one of the secondary recessed surfaces 6a of ferromagnetic material 23, and the molded part at least partially receives said at least one primary flat surface 5 or at least one primary recessed surface 5a of ferromagnetic material 23. For the purpose of providing an example in a non-limiting manner, the molded part may have at least one finger-like structure. The finger-like structure of the molded part has a flat surface 17 that at least partially receives said at least one of the primary flat surfaces 5 of magnet 3 and is designed to limit relative rotation of ferromagnetic material 23. In another example, the finger-like structure of the molded part has a convex surface that at least partially receives said at least one of the primary recessed surfaces 5a of ferromagnetic material 23 and is designed to limit relative rotation of ferromagnetic material 23. Therefore, the ferromagnetic material 23 is retained and indexed in the molded part.

[0058] Furthermore, as in step 74, the tool removal operation is completed, and the shaft 1 and the ferromagnetic material 23 are overmolded with the plastic component 2, wherein at least one of the secondary flat surfaces 6 or at least one of the secondary recessed surfaces 6a is at least partially overmolded with the plastic component 2. To provide an example in a non-limiting manner, the plastic component 2 is at least partially overmolded on the ferromagnetic material such that the plastic component 2 holds at least one of the secondary flat surfaces 6 or at least one of the secondary recessed surfaces 6a of the ferromagnetic material 23 to limit the relative rotation of the magnet 3, and the orientation direction (magnetization direction) can be readily discerned from at least one of the primary flat surfaces 5 or at least one of the primary recessed surfaces 5a of the ferromagnetic material 23, which is at least partially without the plastic component 2. Therefore, the mounting position of the magnet 3 is held and indexed within the plastic component 2.

[0059] Furthermore, as in step 75, the magnetization of the ferromagnetic material is performed by placing the shaft 1 and the ferromagnetic material 23, molded and covered with the plastic component 2, in a magnetic field. The ferromagnetic material 23, molded and covered with the plastic component 2, is positioned and clamped in a tool and then brought close to the coil. In this example, the coil can be a magnetizer core or a C-shaped coil. Current flows through the coil, which generates a strong magnetic field. The ferromagnetic material 23 is placed in the coil such that the anisotropy direction X of the ferromagnetic material 23 is aligned with the magnetic field generated by the magnetizer. The current flowing through the coil must be high enough to saturate the magnetization of the ferromagnetic material 23. Thus, the ferromagnetic material 23 is magnetized.

[0060] As described above, the assembly 10 according to this subject matter, including a shaft 1, a magnet 3, and a plastic component 2, is particularly advantageous in applications where automotive components, such as electromechanical actuators, rotating machines, or pumps, are assembled in motor vehicles. In one example, this arrangement specifically envisions a rotating machine for an automobile, which includes an angular position sensing system 12 configured according to this subject matter. The rotating machine can be an electric machine, preferably a generator or electromechanical drive machine (i.e., an electric motor) or an electric oil pump. In this case, all known examples are conceivable, such as synchronous motors, asynchronous motors, DC motors, or examples of brushless DC motors (BLDC motors) or reluctance motors with rotors made of magnetic poles. Furthermore, the application is not limited to electric motors. Alternatively, the rotating machine can also be an internal combustion engine with a shaft whose rotational position will be detected.

[0061] In another example, the corresponding electromechanical actuator is a gearbox actuator, also known as a shift actuator, specifically used for selecting and shifting gears between gear ranges in an automotive transmission. To perform the above operations, the gearbox actuator includes a shaft 1 configured according to this subject matter and a magnet 3 in the output mechanism. The shaft 1 and magnet 3 are molded and overlaid with a plastic component 2, for example, a sector gear 2a rotatable about a longitudinal axis 4. The magnet 3 has an anisotropic direction X perpendicular to the longitudinal axis 4 of the shaft 1. The magnet 3 has at least one main flat surface 5 or at least one main recessed surface 5a extending at least partially along the longitudinal axis 4, and at least one tangent of the at least one main flat surface 5 or the at least one main recessed surface 5a is parallel to the anisotropic direction X of the magnet 3, and at least partially lacks the plastic component 2 for indicating the orientation of the anisotropic direction X. The output mechanism also includes shift fingers, etc., coupled to the shaft 1. The aforementioned gearbox actuator also includes a drive motor, a controller electrically connected to and configured to control the drive motor, and a reduction mechanism. The output mechanism is coupled to the drive motor via the reduction mechanism. The controller includes at least one magnetic field sensor adapted to detect the angular position of the shaft 1 in which the sector gear 2a is molded.

[0062] In another example, the corresponding electromechanical actuator could be, for example, a parking lock actuator or a transmission lock actuator according to this arrangement, specifically for controlling a parking pawl in an automotive application. The parking pawl is movable between a first position and a second position, wherein in the first position, the parking pawl prevents rotation of the output shaft, and in the second position, the parking pawl does not prevent rotation of the output shaft. To perform the above operation, the parking lock actuator or transmission lock actuator includes a shaft 1 configured according to this subject matter and a magnet 3 in the output mechanism. The shaft 1 and the magnet 3 are molded and covered with a plastic component 2, for example, a sector gear 2a rotatable about a longitudinal axis 4. The magnet 3 has an anisotropic direction X perpendicular to the longitudinal axis 4 of the shaft 1. The magnet 3 has at least one main flat surface 5 or at least one main recessed surface 5a extending at least partially along the longitudinal axis 4, and at least one tangent of the at least one main flat surface 5 or the at least one main recessed surface 5a is parallel to the anisotropic direction X of the magnet 3, and at least partially lacks a plastic component 2 for indicating the orientation of the anisotropic direction X. The aforementioned parking lock actuator or transmission lock actuator also includes a drive motor, a controller electrically connected to and configured to control the drive motor, and a reduction mechanism, the controller including at least one magnetic field sensor adapted to detect the angular position of the shaft 1 in which the sector gear 2a is molded.

[0063] In another example, the corresponding electromechanical actuator could be, for example, an electronic throttle controller according to this arrangement, which is particularly used as a fluid metering valve for an internal combustion engine, in which case a gasoline or diesel engine is possible. It can also be used as an exhaust gas recirculation valve or an EGR valve. The electronic throttle controller includes a fluid metering valve, a control shaft unit, a drive unit, and a gear mechanism coupled to the drive unit. The fluid metering valve is, for example, a throttle valve, valve, or flap that operates between a first position and a second position, and the control shaft unit is connected to the fluid metering valve. The drive unit is configured to rotate the valve between the first and second positions. Rotation of the valve allows control of the flow of fluid flowing in the pipe. To perform the above operations, the control shaft unit is configured according to this subject matter. The control shaft unit includes a shaft 1 and a magnet 3, and is molded and covered with a plastic component 2, for example, a sector gear 2a rotatable about a longitudinal axis 4. The magnet 3 has an anisotropic direction X perpendicular to the longitudinal axis 4 of the shaft 1. The magnet 3 has at least one main flat surface 5 or at least one main recessed surface 5a extending at least partially along the longitudinal axis 4, and at least one tangent of the at least one main flat surface 5 or the at least one main recessed surface 5a is parallel to the anisotropic direction X of the magnet 3, and at least partially lacks a plastic component 2 for indicating the orientation of the anisotropic direction X. The electronic throttling controller also includes at least one magnetic field sensor adapted to detect the angular position of the shaft 1 overlying and molded therein by the sector gear 2a. Other applications of the valve according to the invention are also possible without departing from the scope of the invention.

[0064] However, it is understood that the application is not limited to shift actuators, parking lock actuators, or electronic throttle controllers; this subject can be applied to a variety of other automotive components, including assembly 10 with shaft 1, magnet 3, and plastic parts 2.

Claims

1. A component (10), comprising: A shaft (1) is capable of rotating about a longitudinal axis (4); A magnet (3) disposed near one end of the shaft (1), the magnet (3) having an anisotropic direction (X) perpendicular to the longitudinal axis (4) of the shaft (1), the magnet (3) having at least one main flat surface (5) or at least one main recessed surface (5a) extending at least partially along the longitudinal axis (4); a plastic component (2) overmolded on the shaft (1) and the magnet (3), characterized in that at least one tangent of the at least one main flat surface (5) or the at least one main recessed surface (5a) is parallel to the anisotropic direction (X) of the magnet (3), and at least partially without the plastic component (2) for indicating the orientation of the anisotropic direction (X).

2. The component (10) according to claim 1, characterized in that, The magnet (3) has at least one secondary flat surface (6) or at least one secondary recessed surface (6) extending at least partially along the longitudinal axis (4), and at least one tangent of the at least one secondary flat surface (6) or the at least one secondary surface (6a) is parallel to the anisotropic direction (X) of the magnet (3) and is at least partially molded by the plastic component (2).

3. The component (10) according to claim 2, characterized in that, The at least one main flat surface (5) and the at least one secondary flat surface (6) are opposite to each other, or the at least one main recessed surface (6) and the at least one secondary recessed surface (6a) are opposite to each other.

4. The component (10) according to any one of the preceding claims, characterized in that, The magnet (3) has a cylindrical shape (7) with a diameter D and extends along the longitudinal axis (4) with a height H.

5. The component (10) according to claim 4, characterized in that, The distance A between the at least one primary flat surface (5) and the at least one secondary flat surface (6) is between 0.7 and 0.9 times the diameter D of the magnet (3).

6. The component (10) according to claim 4 or 5, characterized in that, The height H of the magnet (3) is between 0.3 times the actual diameter D of the magnet (3) and the actual diameter D.

7. The component (10) according to claim 4 or 5, characterized in that, The width W of the at least one primary flat surface (5) and the at least one secondary flat surface (6) is determined by the width Provided.

8. The component (10) according to any one of claims 1 to 3, characterized in that, The magnet (3) has a parallelepiped shape.

9. The component (10) according to any one of the preceding claims, characterized in that, The plastic component (2) is a gear, a sector gear (2a), or a rotor.

10. An angular position sensing system (21) comprising a component (10) configured according to any one of the preceding claims and a sensor (22) placed in front of the magnet (3).

11. An electromechanical actuator or rotating machine for automotive applications, comprising the angular position sensing system (21) according to claim 10.

12. A method for manufacturing an assembly (10) having a shaft (1), a magnet (3), and a plastic component (2), comprising the following steps: a) Provide a ferromagnetic material (23) having at least one main flat surface (5) or at least one main recessed surface (5a) and at least one secondary flat surface (6) or at least one secondary recessed surface (6a) extending at least partially along a longitudinal axis (4), and at least one tangent of the at least one main flat surface (5) or the at least one main recessed surface (5a) of the ferromagnetic material (23) is aligned parallel to the anisotropic direction (X) of the ferromagnetic material (23); b) The ferromagnetic material (23) is deposited in a molding (20) near one end of the shaft (1) in an anisotropic direction (X) perpendicular to the longitudinal axis (4) of the shaft (1), wherein the tool holds at least one of the secondary flat surfaces (6) or at least one of the secondary recessed surfaces (6a) of the ferromagnetic material (23), and the molding (20) receives at least one of the at least one primary flat surface (5) or primary recessed surface (5a) of the ferromagnetic material (23) at least partially; c) Remove the tool and mold the shaft (1) and the ferromagnetic material (23) over the plastic component (2), wherein at least one of the at least flat secondary surface (6) or the at least one recessed secondary surface (6a) is at least partially molded over the plastic component (2); d) Magnetize the ferromagnetic material (23) by placing it in a magnetic field.

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