CN106404008A - Shaft-integrated angle sensing device - Google Patents

Abstract

The invention relates to a shaft-integrated angle sensing device. The sensor arrangement includes a sensor element and a magnet module. A sensor is configured to measure the magnetic field and is positioned within the shaft. The shaft is configured to shield the magnet module and sensor element. The magnet module is configured to generate a magnetic field. The sensor element is positioned at least partially within the shaft.

Description

Integrated Angle Sensing Device with Shaft

related application

This application is a continuation-in-part of US Patent Application US 14/474638 filed September 2, 2014 in the United States Patent and Trademark Office, which is hereby incorporated in its entirety.

This application is also a continuation-in-part of U.S. Patent Application Serial No. 14/812,907, filed July 29, 2015, entitled "Magnetic Field Sensor," which was filed May 29, 2014, and entitled A continuation-in-part of U.S. Patent Application Serial No. 12, filed May 30, 2008, entitled "Magnetic-Field Sensor," Serial No. 14/290,780 for "Magnetic-Field Sensor" /130,678, which claims priority to German Patent Application No. 102007025000.4, filed May 30, 2007, the entirety of which is hereby incorporated by reference.

Background technique

Sensors are used in sensing systems to detect characteristics such as light, temperature, motion, and the like. One type of sensor that is commonly used is a magnetic field based angle sensor. The angle sensor measures the direction of the magnetic field and calculates the angle based on the direction of the magnetic field. Other magnetically sensitive sensors measure magnetic flux density.

However, such magnetically based sensors are sensitive to disturbances by magnetic fields. Many systems operate in harsh environments such as automotive systems and have components that can interfere with magnetic fields and cause erroneous sensor measurements.

What is needed are techniques for mitigating or avoiding interference to improve the operation, accuracy and robustness against positioning tolerances of magnetic sensors.

Description of drawings

Figure 1 is a diagram of an integrated sensor system that operates using a magnetic field;

Figure 2 is a cross-sectional view of a shaft-integrated sensor system with a hollow shaft and a ring magnet module;

3 is a cross-sectional view of a shaft-integrated sensor system with a hollow shaft and a pill-shaped magnet;

Figure 4 is a cross-sectional view of an integrated sensor system with a solid shaft and ring magnet module;

Figure 5 is a cross-sectional view of an integrated sensor system with a solid shaft and a pellet magnet;

Figure 6 is a diagram depicting a sensor module system;

Figure 7 is a cross-sectional view illustrating a ring magnet that may be used in a magnet module, such as the magnet module described above;

Figure 8 is a cross-sectional view illustrating a pellet or column magnet that may be used in a magnet module, such as the magnet module described above;

Figure 9 is a flowchart illustrating a method of operating a sensor device;

Figure 10 is a cross-sectional view of a portion of a shaft usable in conjunction with a sensor system as described herein;

Figure 11A illustrates a scenario (scenario) used in the numerical simulation;

FIG. 11B illustrates some results of simulations calculated based on the scenario shown in FIG. 11A ;

Figure 12 illustrates the arrangement of sensors embedded in the shaft in a cross-sectional view;

Figure 12A illustrates a further embodiment of a sensor integrated in the bore of the shaft;

Figure 12B illustrates another embodiment of a sensor integrated in the thin-walled end of a shaft with a sleeve;

Figure 12C illustrates saturation of the magnetizable thin-walled end of the shaft as in the embodiments of Figures 10, 12A and 12B;

Figure 12D illustrates another embodiment of a sensor integrated in the thin-walled end of a shaft with a further sleeve;

Figure 12E illustrates another embodiment of a sensor integrated in the thin-walled end of a shaft with an alternative sleeve;

Figure 13 illustrates the setup for a package of sensors with leads;

14A-14D illustrate symmetry considerations for magnet and sensor arrangements in accordance with the present disclosure;

Figures 15A-15I illustrate various symmetries for the arrangement of the magnet(s) within the thin-walled bore at the end of the shaft;

Figure 16 illustrates a split magnet positioned within a bore;

Figure 17 illustrates a magnet comprising a slot embedded in a bore of the shaft;

Figure 18 illustrates a key to orient the magnet inside the bore of the shaft;

Figure 19A illustrates a further magnet embodiment located within the bore of the shaft;

Figure 19B illustrates yet another magnet arrangement within the tapered bore of the shaft;

Figure 20 illustrates another magnet arrangement within the bore of the shaft;

21A, 21B and 21C illustrate the sealing (sealing) of the opening of the hole including the magnet arrangement and the sensing element;

Figures 22A, 22B illustrate Halbach-type magnet arrangements;

Figure 22C illustrates yet another single non-uniform magnet arrangement.

detailed description

The present invention will now be described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout, and wherein the illustrated structures and devices are not necessarily drawn to scale.

Devices, systems, and methods are disclosed that facilitate angle sensors and mitigate interference in magnetic fields. Harsh environments such as automotive systems have a variety of components and conditions that affect electronics, sensors and magnetic fields. These disturbances can cause erroneous measurements, sensor failure, and require positional tolerances to be met in order to achieve a certain level of precision in the operation of the sensor. Angle sensors are generally focused on identifying the angular position of a rotating object about an axis. In some applications, it may be of interest to clearly identify the angular position within only 180 degrees, ie, half a circle. In other applications, however, it may be of interest to clearly identify the angular position within 360 degrees corresponding to one full revolution of the object about the axis.

FIG. 1 is a diagram of an integrated sensor system 100 that operates using a magnetic field. The system 100 is presented in simplified form to facilitate understanding. The system 100 may be used in harsh environments, automotive systems, vehicle systems, and the like. The system 100 may be manufactured as one or more devices or arrangements.

Hybrid systems, such as automotive systems, have mechanical and electronic components. Mechanical components include engines, motors, wheels, fluids, braking systems, actuators, and more. Electronic components include sensors, processing units, control units, and the like. Mechanical parts can interfere with electronic parts. These disturbances include power surges, power losses, power tracks, high power tracks, vibration, debris, metal pieces/pieces, fluid contamination, transmission fluid contamination (very aggressive), brake disc cleaner, coolant, materials , dirt, etc. The more motors, actuators and other components there are, the more current and fluctuations there are.

Other methods are sensitive to disturbances and do not provide mechanisms for these disturbances.

Typically, an angle sensor will track the rotational movement of an axis or shaft. One approach is to add a sensor to the end of the shaft and encapsulate the sensor. However, packaging adds cost, adds additional processing, and requires additional space. Additionally, such methods also include placing the sensor element at the end of the shaft. This increases the overall length of the axle or components attached to the axle, which requires additional vehicle/engine space. Additional mounts, connectors, etc. are required to mount the sensor on the end of the shaft. These components can further increase the length/space consumed and require even more vehicle/engine space.

System 100 includes optional sensor module 102 , sensor element 104 and magnet module 106 . The sensor module 102 may be in packaged form, or any other form that facilitates placement of the sensor 104, as described further below. System 100 may integrate sensor module 102 with a shield in the form of a housing, shaft, or other component to provide self-shielding. Furthermore, through integration, system 100 consumes less space than other approaches. Additionally, the system 100 utilizes self-shielding to allow components with lower performance while providing suitable or selected precision.

In some implementations, the sensor module 102 may be an integrated component in that the sensor module 102 is integrated into a housing or other component. The sensor module 102 includes an integrated sensor element 104 . Module 102 may also include power conditioning components, signal generating components, storage components, and the like. Although not shown, other components may be included including mounts, fasteners, connections, housings, and the like. In one example, the sensor module 102 is formed on a die with a lead frame. The sensor module 102 is enclosed in a housing using over molded plastic. Connectors of the lead frame are provided and the connectors of the lead frame provide external connections to the sensor module 102, as described in more detail later. The sensing module may be coupled to, or incorporated into, components such as housings, rods, arms, axle legs, and the like.

The sensor element 104 measures the direction of the magnetic field or the direction of the flux of the magnetic field. The element 104 or another component then calculates a characteristic, such as angle or axis position, based on the field direction measurements. The sensor element 104 is configured to receive power, provide measurements, and/or receive control or calibration information. In one example, a single interface is used for both power and measurement results. In another example, multiple wires or ports are used for power and/or communication.

The sensor element 104 is an absolute or 360 degree type sensor, meaning that it can uniquely measure flux at any angle throughout one revolution. It is of a suitable type, such as a magneto-resistive or magneto-sensitive type element.

The magnet module 106 is fixed or attached to, or integrated with, the component under test and is configured to generate a magnetic field proximate to the sensor element 104 . In one example, the magnet module 106 may be magnetized in a diametrical direction. The magnet module 106 may include magnets of various sizes and shapes. Some example shapes include pellet or solid magnets, ring magnets, and the like. Choose size to provide suitable magnetic field. Typically, dimensions include thickness and diameter.

Disturbances such as those given above may cause disturbances to the magnetic field measured by the sensor element 104 . However, sensor module 102 is integrated with components that shield module 102 and element 104 without requiring extensive packaging or other mechanisms to mitigate interference. Components that provide shielding for the sensor element 104 and the magnet module 106 include, for example, rotatable objects such as shafts, rods, etc., composed of suitable materials. In one example, suitable materials include relatively soft magnetic materials having a magnetic permeability greater than one.

FIG. 2 is a cross-sectional view of an integrated sensor system 200 with a hollow shaft and ring magnet module. System 200 is presented in simplified form to facilitate understanding. System 200 may be used in harsh environments, automotive systems, vehicle systems, and the like. System 200 may be manufactured as one or more devices. Additional details for some components may be referenced from the above description of like numbered components.

System 200 includes housing 208 , sensor module 102 , sensor element 104 , magnet module 206 and shaft 210 . System 200 integrates sensor module 102 with shaft 210 , which shields sensor module 102 and magnet module 206 from interference and enhances the magnetic field generated by magnet module 206 .

The sensor module 102 includes a sensor element 104 formed within a housing. The housing is typically, but not limited to, overmolded plastic. The sensor element 104 may be configured with a lead frame. The module 102 includes connections from the lead frame of the sensor element 104 to ports or external connections, as explained in more detail with respect to FIG. 13 .

Housing 208 may be a transmission, a compartment, a powertrain internal combustion engine, and the like. Housing 208 is configured to receive and support shaft 210 . In one embodiment, housing 208 includes a hollow recess into which shaft 210 fits. Bearings 212 or another component/device are configured to facilitate rotation of shaft 210 without excessive friction. The housing 208 may also include a module opening into which the sensor module 102 is embedded or positioned. It should be appreciated that the sensor module, when placed in the module opening, will facilitate the intended positioning of the actual sensor element 104 relative to the rotatable shaft 210 and magnet 206 such that the rotation of the shaft 210 is "visible" to the sensor element 104 . It should be noted that the sensor module 102 is removable from the housing 208 . In another example, the sensor module is non-removably attached to the housing 208 .

In one example, housing 208 provides a hermitic seal that protects sensor module 102 from debris and contaminants. Additionally, housing 208 may be configured to provide magnetic and/or electrical shielding. The aspect of shielding the sensor element 104 and/or the magnet 206 from any external magnetic field will be described in more detail below with reference to FIGS. 10-18 .

Shaft 210 is separate from housing 208 . A first end of the shaft is attached to a motor or other rotatable object, and a second end of the shaft is proximate to housing 208 . The second end of shaft 210 may be coupled with a bearing to facilitate rotation. Shaft 210 may be part of an automotive system, such as a driveline, transmission system, or the like. The shaft 210 is generally an elongated cylindrical rod made of a suitable material, such as metal, soft magnetic material, and the like. Some examples of suitable metals include steel and aluminum. Examples of soft magnetic materials include materials whose magnetic permeability is greater than 1. The shaft 210 rotates at a range of revolutions per minute (RPM) and in a direction of rotation clockwise or counterclockwise. RPM may include a low RPM range, such as 0 to 200 RPM, and a high RPM range, such as a range over 4000 RPM.

Shaft 210 is shown having an axis of rotation shown as Z. Shaft 210 rotates about an axis of rotation in a direction of rotation, which rotation may be clockwise or counterclockwise.

Shaft 210 may be hollow, solid, or otherwise configured. In FIG. 2, the shaft 210 is hollow and has a selected wall thickness. Alternatively, shaft 210 may be solid and include thin-walled ends as shown in FIG. 2 . At least some of the sensor mass 102 and the sensor element 104 extend partially to the open portion at the second end of the shaft 210 . Additionally, the magnet module 206 is also located at least partially within the open portion of the shaft. By being hollow, the shaft can be of lower cost and weight than a solid shaft.

The magnet module 206 generates a magnetic field having a magnetic flux and configured for measurement. In this example, the magnet module 206 includes a ring magnet positioned along the inner surface of the shaft 210 , ie, the inner circumferential surface in FIG. 2 . The ring magnet partially surrounds the sensor mass 102 with respect to the axis of rotation z and surrounds the sensor element 104 .

In this example, sensor module 102 is integrated into housing 208 . The sensor module 102 may include an O-ring or similar material to seal between the sensor module 102 and the housing 208 (not shown in FIG. 2 ). The sensor element 104 is positioned proximate to the second end of the module 102 . The sensor element 104 typically measures the magnetic field generated by the magnet module 206 , and more precisely, when used as an angle sensor, measures the direction of this magnetic field. As the shaft 210 rotates, the magnetic field generated by the magnets appears relative to the sensor element 104 as a rotating magnetic field, which can be used to monitor the rotational position of the shaft.

Measurements obtained by sensor element 104 are used to calculate angular related measurements including radial position of the shaft, angular position of the shaft, revolutions per minute (RPM), direction of rotation, and the like.

A control unit, such as an electronic control unit (ECU), may receive measurements and or angle-related information from the sensor module 102 .

3 is a cross-sectional view of a shaft-integrated sensor system 300 having a hollow shaft, or at least a thin-walled end of the shaft, and a pellet magnet. System 300 is presented in simplified form to facilitate understanding. System 300 may be used in harsh environments, automotive systems, vehicle systems, and the like. System 300 may be manufactured as one or more devices. System 300 is similar to system 200 described above, however, this system 300 utilizes pellet or round shaped magnets rather than ring magnets. Additional details for some components may be referenced from the above description of like numbered components.

System 300 includes housing 208 , sensor module 102 , sensor element 104 , magnet module 306 , and shaft 210 . System 300 integrates sensor module 102 into shaft 210 that electrically, mechanically, and/or magnetically shields sensor module 102 from interference.

The sensor module 102 includes a sensor element 104 formed within a housing. The housing is overmolded plastic. The sensor element 104 is typically configured with a lead frame. The module 102 includes connections from the lead frame of the sensor element 104 to ports or external connections.

Housing 208 may be part of a powertrain, transmission system, or the like. Housing 208 is configured to receive and support shaft 210 . Housing 208 includes a hollow recess, referred to as a housing recess, into which shaft 210 fits. Bearings 212 or another component/device are configured to facilitate rotation of shaft 210 without excessive friction.

Shaft 210 is separate from housing 208 . A first end of the shaft is attached to a motor or other rotatable object and a second end is proximate to housing 208 . Shaft 210 is generally an elongated cylindrical rod composed of a suitable material such as described above. The shaft 210 rotates at a range of revolutions per minute (RPM) and in a direction of rotation clockwise or counterclockwise. RPM may include a low RPM range, such as 0 to 200 RPM, and a high RPM range, such as a range over 4000 RPM.

Shaft 210 may be hollow, solid, or otherwise configured. In FIG. 3, the shaft 210 is again hollow and has a selected wall thickness. A portion of the sensor module 102 extends partially to the open portion at the second end of the shaft 210 . The magnet module 306 is located within the open portion of the shaft.

The magnet module 306 generates a magnetic field having a magnetic flux and configured for measurement. The shaft 210 enhances the generated magnetic field. In this example, the magnet module 306 includes a pellet or circular magnet positioned across an opening in the shaft 210 . The pellet magnet is positioned along the same axis z as the sensor mass 102 and the sensor element 104 . Additionally, the pellet magnet has a diameter and thickness selected to provide a suitable magnetic field. The diameter may be smaller than the diameter of the inner surface of the shaft 210 .

As mentioned above, the sensor module 102 is integrated in the housing 208 . The sensor module 102 may include an O-ring or similar material to seal between the sensor module 102 and the housing 208 . The sensor is located near the second end of the module 102 . The sensor element 104 measures the magnetic field, more precisely the orientation of the magnetic field generated by the magnet module 306 .

Measurements obtained by the sensor elements 104 are used to calculate the azimuth or angular position of the shaft, revolutions per minute (RPM), direction of rotation, and the like.

A control unit, such as an electronic control unit (ECU), may receive measurements and/or angle-related information from the sensor module 102 .

FIG. 4 is a cross-sectional view of a sensor system 400 having a solid shaft 410 and a ring magnet module 206 . System 400 is presented in simplified form to facilitate understanding. System 400 may be used in harsh environments, automotive systems, vehicle systems, and the like. Additionally, system 400 may be fabricated as one or more devices. Additional details for some components may be referenced from the above description of like numbered components.

System 400 includes housing 208 , sensor module 102 , sensor element 104 , magnet module 206 , and shaft 410 . The system 400 integrates the sensor module 102 in a shaft 410 that electrically, mechanically, and or magnetically shields the sensor module 102 from interference.

The sensor module 102 in turn includes a sensor element 104 that is optionally formed within the housing. In one example, the housing is overmolded plastic. The sensor element 104 may be configured with a lead frame. Module 102 may include connections from the lead frame of sensor element 104 to ports or external connections.

Housing 208 may be part of a powertrain, transmission system, or the like. Housing 208 is configured to receive and support shaft 410 . Housing 208 includes a hollow recess into which shaft 410 fits. Optional bearing 212 or another component/device is configured to facilitate rotation of shaft 410 without excessive friction.

Shaft 410 is separate from housing 208 . A first end of the shaft is attached to a motor or other rotatable object, and a second end of the shaft is proximate to housing 208 . The shaft 410 is generally an elongated cylindrical rod composed of a suitable material, such as metal. Some examples of suitable metals are shown above. The shaft 410 rotates at a range of revolutions per minute (RPM) and in a direction of rotation clockwise or counterclockwise. RPM may include a low RPM range, such as 0 to 200 RPM, and a high RPM range, such as a range over 4000 RPM.

In this example, shaft 410 is solid and has a selected diameter. The second end of the shaft 410 includes a shaft lumen 414 . A cavity 414 is formed in the second end using a suitable mechanism, such as drilling. Cavity 414 has a diameter and a depth. At least a portion of the sensor module 102 extends into the shaft cavity 414 . Additionally, the magnet module 206 is located within the shaft cavity. Being solid, the shaft 414 may have higher strength than the hollow shafts discussed with respect to FIGS. 2 and 3 .

The magnet module 206 generates a magnetic field having a magnetic flux and configured for measurement. In this example, the magnet module 206 includes a ring magnet positioned around the inner surface of the shaft cavity 414 . The ring magnet partially surrounds the sensor mass 102 in the z-direction and surrounds the sensor element 104 . A ring magnet 206 typically provides a better magnetic field than a pellet magnet for measurements with respect to axial displacement.

In this example, sensor module 102 is integrated into housing 208 . The sensor module 102 may include an O-ring or similar material to seal between the sensor module 102 and the housing 208 . The sensor element is positioned proximate to the second end of the module 102 . The sensor element 104 measures the magnetic field generated by the magnet module 206 .

Measurements obtained by the sensor element 104 are used to calculate the radial position of the shaft, revolutions per minute (RPM), direction of rotation, and the like. A control unit (not shown), such as an electronic control unit (ECU), may receive measurements and or angle-related information from the sensor module 102 .

5 is a cross-sectional view of a shaft-integrated sensor system 500 with a solid shaft and a pellet magnet. System 500 is presented in simplified form to facilitate understanding. System 500 may be used in harsh environments, automotive systems, vehicle systems, and the like. Additionally, system 500 may be fabricated as one or more devices. Additional details for some components may be referenced from the above description of like numbered components.

System 500 includes housing 208 , sensor module 102 , sensor element 104 , magnet module 306 , and shaft 410 . System 200 integrates sensor module 102 and magnet module 306 into a shaft 410 that electrically, mechanically, and or magnetically shields sensor module 102 from interference.

The sensor module 102 includes a sensor element 104 formed within a housing. The housing is overmolded plastic. The sensor element 104 may be configured with a lead frame. The module 102 includes connections from the lead frame of the sensor element 104 to ports or external connections.

Housing 208 may be part of a powertrain, transmission system, or the like. Housing 208 is configured to receive and support shaft 410 . Housing 208 includes a hollow recess into which shaft 410 fits. Bearings 212 or another component/device are configured to facilitate rotation of shaft 410 without excessive friction.

Shaft 410 is separate from housing 208 . A first end of the shaft is attached to a motor or other rotatable object and a second end is proximate to housing 208 . Shaft 410 is generally an elongated cylindrical rod composed of a suitable material such as shown above. The shaft 410 rotates at a range of revolutions per minute (RPM) and in a direction of rotation clockwise or counterclockwise. RPM may include low RPM ranges and high RPM ranges, and variations thereof.

Shaft 410 is solid and has a selected diameter. The second end of the shaft 410 includes a shaft lumen 414 . Using suitable mechanisms, a cavity 414 is formed in the second end. Cavity 414 has a diameter and a depth. Portions of the sensor module 102 partially extend into the shaft cavity 414 . Additionally, a magnet module 306 is located within the shaft cavity.

The magnet module 306 generates a magnetic field having a magnetic flux and configured for measurement. In this example, the magnet module 306 includes a pellet magnet positioned in the shaft cavity 414 . The pellet magnet is positioned on the axis with the sensor 104 , ie the z-axis in FIG. 5 . Additionally, the pellet magnet has a diameter and a thickness as described above with respect to FIG. 3 .

In this example, sensor module 102 is integrated into housing 208 and shaft 410 . The sensor module 102 may include an O-ring or similar material to seal between the sensor module 102 and the housing 208 . The sensor is located near the second end of the module 102 . The sensor element 104 measures the magnetic field generated by the magnet module 306 , or the direction of the magnetic field. The magnetic field from magnet 306 is “visible” to the sensor as a rotating magnetic field indicating the angular position of rotational axis 410 .

The measurements obtained by the sensor element 104 are used to calculate the radial position of the shaft, revolutions per minute (RPM), direction of rotation, etc., as already explained above. A control unit (not shown), such as an electronic control unit (ECU), may receive measurements and/or angle-related information from the sensor module 102 . Measurement results or information include analog or digital raw data, calculated angle information, and more.

FIG. 6 is a diagram depicting a sensor module system 600 . System 600 is usable with the above systems and devices and is provided to facilitate understanding.

System 600 includes sensor module 102 , interface 616 , and controller or control unit 614 . The sensor module 102 includes a sensor element 104 . The sensor element 104 is a magnetic sensitive technology, such as magnetoresistive, Hall effect, or the like. The sensor element 104 is configured to measure a magnetic field, magnetic flux density, magnetic field direction, etc. proximate to the element 104 . The sensor element 104 is formed on the die with a lead frame for power and providing measurements.

The sensor module 102 includes a housing 618 formed from a suitable material, such as overmolded plastic. Housing 618 generally seals sensor element 104 from debris and other interference.

Interface 616 is connected to sensor element 104 . Interface 616 may include one or more wires/connections to sensor element 104 and external to housing 618 . Interface 616 is configured to communicate measurements from sensor element 104 to controller 614 and to provide power to sensor element 104 .

Controller 614 is connected to interface 616 and is configured to control sensor element 104 and receive magnetic field/flux measurements from sensor element 104 . The controller 614 determines angular information about the components, such as angular position, angular position, rotational velocity, acceleration, and the like. The components are typically rotatable components such as motor shafts, wheels, powertrain shafts, prop shafts, and the like. In particular, controller 614 is configured to determine angular position, angular direction, RPM, and the like.

FIG. 7 is a cross-sectional view of a ring magnet 700 that may be used in a magnet module, such as the one described above. Ring magnet 700 may be used in the above system to generate a magnetic field for measuring angular information including position and RPM.

The magnet 700 is positioned within the end of a shaft of a motor, wheel, or the like. A magnet generates a suitable field determined by its composition and size.

Dimensions include outer diameter 720 , width thickness 722 , and inner diameter 724 . The difference between the inner diameter 724 and the outer diameter defines the ring thickness. In general, the greater the ring thickness and width thickness, the greater the magnetic field generated and the greater the tolerance of the sensor element against displacement of the sensor relative to the magnet (also known as positioning tolerance).

FIG. 8 is a cross-sectional view of a pellet or round magnet 800 that may be used in a magnet module, such as the one described above. A pellet magnet 800 may be used in the above system to generate a magnetic field for measuring angular information including position and RPM.

The magnet 800 may be positioned within the end of a shaft of a motor, wheel, or the like. The magnet 800 generates a suitable magnetic field distribution or flux determined by its composition and size.

Dimensions include diameter 820 and thickness 822 . In general, the larger the diameter 820 and the larger the thickness 822, the larger the magnetic field generated and the more resistant the sensor element can be against positioning tolerances, as will be explained in more detail later.

FIG. 9 is a flowchart illustrating a method 900 of operating a sensor device. Method 900 embeds or integrates a sensing module into a shaft to provide shielding against interference and optionally enhance magnetic field generation. Method 900 may be used in conjunction with the above systems, devices, and variations thereof.

Method 900 begins at block 902, where a sensor module is deployed or positioned into a shaft or housing. The shaft provides shielding to the sensor module such that interference, such as that described above, is mitigated or avoided. The housing may be the shell or wall of a compartment such as an automotive transmission component or the like. The sensor module may be overmolded and is typically removable from the housing. The sensor module comprises a sensor element (magnetoresistive) configured to measure the magnetic field in one, two or three axes (1D, 2D, 3D) or directions of the magnetic field.

The shaft is configured with a shaft recess, and the magnet module is positioned within the shaft recess at block 904 . The shaft recess may be formed in a solid or hollow shaft by drilling or another suitable mechanism. The magnet module includes magnets, such as ring magnets or pellet magnets.

At block 906, a magnetic field is generated by the magnet module. As the shaft rotates, the magnetic field rotates with the shaft. The magnetic field module is substantially shielded from interference by the shaft, as a result, in the absence of interference, a magnetic field is generated.

At block 908, the magnetic field is measured by the sensor module. The sensor module is shielded by the shaft, and as a result, the sensor module is substantially shielded from interference. As a result, magnetic field measurements using some shielding are generally more accurate than unshielded methods.

Angle information is determined by the control unit at block 910 based on the magnetic field measurements. Angular information includes, for example, the rotational speed of the shaft, the angular position of the shaft, and the like. It will be appreciated that the angular information is alternatively derived by sensor elements and is being forwarded to the ECU.

Focusing on an arrangement as in Fig. 10, it will be discussed in the following analysis how deep inside the axis or tube 101 the sensor element should preferably be located (as discussed eg with respect to Figs. 1-6). Figure 10 shows a cross-sectional view of a shaft 101 with a hole at its left end. The hole diameter is Di. The shaft 101 may be made of soft magnetic material. This shows that the relative permeability μ _r is greater than 100, typically between 1000 and 10000, and the coercive force is small, typically less than 1 kA/m. Magnets (see, for example, magnet 206 in FIGS. 2 and 4, magnet 306 in FIGS. 3 and 5, magnetic ring 700 in FIG. 7, or magnetic pellet 800 in FIG. The rules below are irrelevant.

The sensor element 104 (not shown in FIG. 10 ) has a sensitive point, which is represented by a cross x lying on the axis of rotation z. Regardless of a given magnet, the sensitive point of a magnetic field sensor element 104 (eg sensor element 104 of FIGS. 1-6 respectively) should preferably be inside the hole at a distance da, where da>0.4×Di. In this condition, the end of the magnetically permeable, thin-walled shaft will effectively shield the sensor element 104 from external magnetic fields. If the sensor element 104 is embedded greater than da=0.4×Di, the shielding is generally only moderately increased again for large da. If the sensor element 104 is embedded less than da=0.4×Di, a substantial part of any external magnetic field is still present at the sensor location and can impair the (angular) sensor function of the sensor element 104 .

FIG. 11A shows the configuration used for the numerical simulations in order to achieve the above estimate that the embedding da of the sensor element 104 is less than 0.4×Di into the thin-walled end of the rotatable shaft 101 . The parameters assumed in the simulation are: the inner diameter of the shaft Di = 22mm, the outer diameter of the shaft is 26mm, and the relative magnetic permeability μ _r of the shaft changes from 100 to 7400. The tube 101 extends from z=-50mm to z=+50mm along the z-direction. Only 1/8 of the geometry is modeled in FIG. 11A due to symmetry considerations. In these simulations, a magnetic disturbance field is applied in the _Bx direction, and it is assumed that the sensor element 104 is sensitive to the _Bx component.

FIG. 11B illustrates the results of a simulation based on the parameters and settings as outlined in FIG. 11A . In FIG. 11B the magnitude is plotted in proportion to the _Bx component sampled at the sensor location versus the applied _Bx component at a large distance outside the tube.

As the abscissa for the plot of FIG. 11B , the z position is plotted against the ratio of the diameter (at z=0.05 mm from the end of the tube) equal to (−1)×da/ Di. The parameter that was varied in the simulation of Fig. 1 IB was the relative permeability μ _r .

Shielding is very good if the test point, ie the potential sensor location along the z-axis, is half the diameter inside the tube 101 . Deep inside the tube 101, according to Kaden und Schirmung in der Nachrichtentechnik”, p.82, shielding as

where d represents the wall thickness. According to FIG. 10 , 2×d is equal to (outer diameter D−inner diameter Di).

When the magnetic field sensing element is located deep inside the hole, according to this formula, the following thumb rule for the angular error can be derived: Angular error [°]=ca.(57/μ _r )×(Di/d)×( B _d /B _m ), where the disturbing magnetic field is B _d , and the magnetic field of the magnet is B _m . Often, the disturbing magnetic field is as high as 1.5mT, the magnetic field of the magnet is 40mT, and the angular error should be less than 0.2°. Therefore, the design rule: μr ^* d/Di>10 is achieved.

The product of the relative permeability μ _r of the shield and the ratio of its thickness d to the inner diameter should be greater than 10.

example:

The inner diameter of the tube 101 is 22 mm and its wall thickness is 2 mm, the field of the magnet is 40 mT, and the disturbance magnetic field is 1.5 mT. If the sensor is located 11mm inside the tube, where μr = 800, the shielding is 3%, so the disturbance inside the tube is 0.03 x _1.5mT = 0.045mT. This gives an angular error: 0.045/40×180/pi=0.065°, and gives: μ _r ×d/Di=800×2/22=73>10.

If μ _r is reduced by a factor of 7.3, this gives the limit value μ _r × d/Di = 10 and leads to an angular error: 0.065° × 7.3 = 0.47°. For better shielding, a larger μ _r and/or a thicker wall of the tube 101 and/or a smaller diameter Di of the hole, respectively, are advantageous.

From the above numerical simulations, one of ordinary skill in the art will understand that for small μ _r , the shielding is smaller than for large μ _r - which is not important. Those of ordinary skill in the art will further appreciate that for large μ _r , it is of greater concern to embed the sensor element 104 deep enough in the bore of the shaft 101: that is, if the sensor element 104 is only 0.4×Di( which corresponds to the abscissa value (z-0.05)/0.022=-0.4) embedded in the hole, the shielding is very close to the same for μr=7400 and μr=3200, whereas if the sensor element 104 is in Di (which is the same as (corresponding to the abscissa value (z-0.05)/0.022=-1), the external magnetic field shielded by the curve of μ _r =7400 is 2.5 times that shielded for the case of μ _r =3200.

Another aspect to consider is the effect of eddy currents and/or hysteresis on arrangements in which the sensor element 104 and/or magnets are arranged within a bore along an axis of rotation.

If the magnetic sensing element 104 is positioned along the axis of rotation (which is the z-axis in FIG. 10 ) and a permanent magnet is attached to the rotatable shaft, there are two mechanisms that shield the magnetic sensing element 104 from external magnetic field disturbances. possibility:

(i) the shield can be stationary relative to the magnet, or (ii) the magnet and shield can rotate relative to each other.

In case (i), the shield may be attached to the magnet or shaft 101 such that the magnet and shield rotate around the (magnetic field) sensing element 104 synchronously. In case (ii), the shield can be attached to the sensor element 104 or a stator such as a mounting point of the shaft without rotating with the shaft.

Preferably, the shield does not move relative to the magnet. Such an arrangement prevents the strong fields of the magnets (206 in Figs. 2, 4, 306 in Figs. 3, 5, 700 in Fig. 7 and 800 in Fig. 8) from generating eddy currents inside the shield. These eddy currents should be avoided because they generate secondary magnetic fields which cause angular errors in the angular measurements of the sensor 104 . Eddy currents cause a magnetic field that lags the rotating magnetic field during shaft rotation, which is more critical the faster the shaft 101 rotates.

In addition, there are small forces between the eddy currents and the magnet, which can interfere in the form of, for example, rotational energy dissipated as heat.

Furthermore, precise relative positioning between the shield and the magnet is of concern when using the shield. Assuming the magnet and shield are not coaxial, this can distort the magnetic field sensed by the sensor element 104 and lead to angular errors. In general, it is simpler to define the exact position between the shield and the magnet if they do not move relative to each other. Conversely, their relative positioning is less precise if they rotate relative to each other, for example due to play in the bearings.

Ultimately, the hysteresis of the shield can lead to additional angular errors for the measured angles. If the direction of rotation changes frequently: the shield can add small magnetic distortions to the magnetic field induced by the magnet. The magnetic distortion due to the hysteresis of the magnetic shield is typically different for clockwise and counterclockwise rotations because the hysteresis of the shield causes the total field to lag the field of the magnet.

In certain cases, it may still be preferable to use a magnetic shield that is stationary to the sensor 104, and thus the magnet rotates relative to the shield: such an arrangement is interesting if the moment of inertia of the shaft 101 needs to be kept small , making it unnecessary to mount the shield on the shaft 101.

In earlier parts of this disclosure, sensing element 104 was described as an integrated circuit. Alternatively, the sensing element 104 may be realized as a separate element. Both options have their own advantages, as explained in more detail below.

An angle sensor circuit implementing the sensing element 104 typically requires at least one magnetic field sensing element to detect the rotational position of a magnet based on the (rotating) magnetic field at the sensor location. For this purpose, e.g. AMR (Anisotropic Magneto-Resistance), GMR (Giant Magneto-Resistance), TMR (Tunneling Magneto-Resistance), CMR (Colossal Magneto-Resistance), Hall plates, vertical Hall-effect devices, MAGFET or magneto-resistive The magnetoresistance of the sensor element.

In many cases, the sensor circuit even requires two or more such sensor elements, in order to realize the sensing element 104, which are aligned in different orientations: the magnetoresistance or Hall effect In the case of devices, their reference direction (which is the direction of current flow in the case of AMR, Hall effect devices and MAGFETs, and the direction of the pinned magnetization in the case of GMR, TMR, CMR) . The different directions need to be significantly different, which means a difference of at least 15°.

In an ideal setup, the different directions are 90° apart; except for AMR where the different directions are 45° apart. These one or more magnetic field sensing elements should be small relative to the magnet and close together (closer compared to the characteristic size of the magnet): if the magnet is 10 mm in size, the sensor element 104 is implemented with All magnetic field sensing elements for calculating angles should be within an area of <0.5 mm (ie 1/20 of the magnet). As a preferred upper limit, it can be said that they should not be separated by more than 1/10 of the magnet size. The size of the magnets should be interpreted as follows: The magnet arrangement is typically characterized by three spatial dimensions. Depending on the circumstances, the three spatial dimensions may be the same, in which case this dimension may be considered the size of the magnet. However, if the three spatial dimensions of the magnet are not the same, for the remainder of this disclosure, any one of the three spatial dimensions may be considered to represent the size of the magnet. If only the magnetic field sensing element is placed inside the hole 101, or if the magnetic field sensing element plus signal conditioning circuitry is placed inside the hole 101 (best seen in FIG. 10), then for implementing the sensing element 104, it is is irrelevant. In the first case, the sensing element 104 may be implemented using a separate transducer, and in the latter case, the sensing element 104 may be implemented using an integrated sensor.

An integrated sensor shall be deemed to include an integrated circuit. An integrated circuit is an electronic circuit that powers the sensor elements and optionally conditions their output signal eg by pre-amplification and A/D conversion and calibration for temperature drift etc.

Depending on the circumstances, it may be of interest to realize the integrated sensor on a single chip, or as a multi-chip solution in a common package. TMRs are ideally suited as discrete magnetic field sensing devices because they generate large signals that can be transmitted to signal conditioning circuits over distances of a few centimeters or tens of centimeters. It is also possible to mount several chips in a single electronic package and to embed them in the holes of the shaft 101 .

Finally, it should be mentioned that if the integrated sensor implementing the sensing element 104 is a 3D magnetic field sensor, the integrated sensor or more precisely the sensor chip does not need to be inside the magnet or along the z-axis or in any predefined orientation. Align inside the axis 101. A 3D magnetic field sensor should be interpreted as a sensor that measures substantially all components of the magnetic field vector. Such a 3D magnetic field sensor may consist of a Hall plate that detects eg the x component of the magnetic field vector, a vertical Hall effect device that detects eg the y component of the magnetic field vector, plus a vertical Hall effect device that detects eg the z component of the magnetic field vector. Those of ordinary skill in the art will readily appreciate other possible implementations of 3D sensors, which shall not be explained here for the sake of simplicity.

Those of ordinary skill in the art will further appreciate that the bearings used in positioning the sensing element 104 within the shaft 210 can have an impact on the performance of the angle sensor 104, as will be discussed briefly below.

FIG. 12 illustrates a cross-sectional view of the end of the shaft 210 including the magnet 206 . Bearings 212 are used to mount housing 208 , which in turn aids in mounting sensor element(s) 104 . Since the magnetic field sensing element(s) 104 and magnet 206 are placed inside the bore at the end of the shaft 210, the presence of the sensing element(s) 104 and/or magnet 206 interferes with the bearing 212 of the shaft 210 (e.g., Ball bearings, but not limited thereto), are also typically near the end 210 of the shaft.

On the one hand, the hole reduces the strength of the shaft 210 . If the wall thickness ((D-Di)/2 in FIG. 10) is too low, it may happen that under heavy loads, the end of the shaft 210 deforms, which can cause the magnet 206 to break or loosen and no longer Rigidly attached to shaft 210 . If the bearing 212 fails, it can get hot, and this rise in temperature can cause the magnet 206 to fail, or disintegrate or come loose from the end of the shaft 210 . Bearings 212 often employ some kind of lubricating oil to reduce friction, and this lubricating oil can reach sensor package 102 and/or magnet 206, where it can cause unwanted chemical interactions (e.g., reducing the friction of attaching magnet 206 to shaft 210). glue strength).

A simple solution to these problems is to move the sensor element 104 and magnet deeper inside the hole, which is recommended anyway, to improve electromagnetic shielding.

Figure 12A illustrates a first solution to some of the problems associated with bearings as previously described. Figure 12A shows a cross-sectional view of the end of the shaft 101 parallel to the axis indicating rotation as the z-axis.

In FIG. 12A , the bearing 212 is pulled out further above the shaft 101 than in FIG. 12 , that is to say, the bearing is positioned farther from the bore. In the setup of FIG. 12A there are two magnets 206 which generate a magnetic field at the location of the sensing element 104 . Without limitation, the magnet 206 may be implemented as a single component, or include more than two components. The position of the sensing element 104 at a distance da away from the opening of the hole is again indicated by the cross x, as discussed previously in connection with FIG. 10 .

For the arrangement of FIG. 12A , the forces and mechanical stresses experienced by the magnets 206 and induced by the bearings 212 are minimized. In other words, the interaction between the bearing 212 and the magnet 206 is reduced compared to the arrangement discussed in FIG. 12 . Thermal coupling between the bearing 212 and the magnet(s) is minimized in the arrangement of FIG. 12A compared to the arrangement of FIG. 12 . The shaft 101 may have a small shoulder 103 (eg, 1/10 mm radially) which avoids damage to the thin walled portion of the shaft when the bearing 212 is pulled out of the shaft 101 .

Fig. 12B illustrates the situation after the sleeve 214a is installed on the thin-walled end of the shaft 101 as shown in Fig. 12A. For the sake of brevity, like elements are illustrated using like reference numerals. Due to the overall increased wall thickness at the end of the shaft 101, the implementation of Figure 12B will improve shielding relative to the arrangement of Figure 12A:

It should be noted that a slight eccentricity of the outer sleeve 214a (eg, due to installation tolerances—not shown in FIG. 12B ) is very likely not to increase the angular error of the angular sensor, ie, sensing element(s) 104 . This is because the inner shield formed by the thin-walled portion of thickness d is dominant. That is, the inner shield shields the magnets from the outer sleeve 214a such that any interaction between the magnets 206 and the sleeve 214a is greatly reduced by the inner shield. Note, however, that the outer sleeve 214a increases the shielding efficiency with respect to external magnetic interference.

Preferably, d2>d should be maintained, ie the outer sleeve 214a should have a greater thickness d2 than the thin-walled end of the shaft 101 . However, even if d2>d is not maintained, the outer sleeve 214a still improves shielding, but with lower efficiency.

Even more preferably, da2>da should be maintained, ie the outer sleeve 214a is axially greater than the distance da by which the magnetic field sensing element(s) 104 are embedded in the hole. However, even if this condition is not met, the outer sleeve 214a still improves shielding, but with lower efficiency.

The sleeve 214a is preferably a soft (magnetic) material with a large relative magnetic permeability μ _r > 10, preferably μ _r > 100, even more preferably μ _r > 1000, and even more preferably μ _r > 10000 . It is to be noted that the sleeve 214a may be made of a different material than the shaft 101 . For the sleeve 214a and the shaft 101 to be made of different materials, it is preferred that the sleeve 214a has a larger μ _r than the shaft 101 because the (permanent) magnet 206 has a strong magnetization. The magnet 206 will also magnetize the thin-walled end of the shaft 101 due to its close proximity to the thin-walled shaft end of wall thickness d. Magnetization of the thin-walled shaft end will worsen its shielding capability: the thin-walled shaft end will be closer to saturation, thereby reducing its effective permeability for small superimposed external magnetic fields.

In the context of the present disclosure, saturation is to be understood as substantially all magnetic moments within materials aligned with a (strong) net magnetic field such that they cannot respond further to additionally superimposed small magnetic fields.

As a result, the thin-walled end of the shaft 101 can no longer be shielded against superimposed small magnetic fields. The net effect is that those parts of the shaft 101 exposed to large magnetic fields are less effective for shielding - they will act as if the walls of the thin-walled ends become even thinner in magnetic induction. The greater the relative magnetic permeability μ _r of the material, the smaller the magnetic field to saturate the material.

Figure 12C illustrates this relationship. B is the magnetic flux density in Tesla (Tesla) [T], H is the magnetic field in amperes per meter [A/m], and μ0 is the magnetic permeability of vacuum (=4π×10 ^-7 [T ]), and B _rem is the remanence of the material, which is obtained when all internal magnetic moments (moments) are aligned along the excitation H field: the steeper the curve is near the original H=0, the higher the relative permeability μ _r is large, but this also means that the material saturates at a smaller magnetic field H ₁ < H ₂ than the material near the original H=0, with a smaller slope, as indicated by the dashed line in Figure 12C for comparison like that.

It is also conceivable that the sleeve 214a (see FIG. 12B ) is the only component shielding the static magnetic field in the arrangement of FIG. 12B . Such a situation may occur, for example, if the shaft 101 is made of a non-magnetic material such as aluminum or brass, or carbon fiber, while the sleeve 214a is made of a soft magnetic material. Under such conditions, the sleeve 214a will shield the magnetic field sensing element(s) 104 from external magnetic field disturbances.

Shield 214a also minimizes unwanted interactions between bearing 212 and magnet 206 . It will be appreciated that the bearing 212 has movable components (eg, balls), which may be magnetic, and thus may be magnetized due to the magnetic field of the magnet 206 . As a result, magnetized bearing 202 may generate a less well-defined magnetic field superimposed on the magnetic field of magnet 206 at the location of magnetic field sensing element(s) 104 of length da inwardly into the bore, as Cross x is shown. Therefore, the magnetized bearing 202 will cause additional errors in the measurement of the rotational position of the shaft 101 .

It will be appreciated that the magnet 206 of FIG. 12B is cylindrical, whereas the magnet of FIG. 12A includes two individual magnets 206 . In both cases, the hole in the end of the shaft is terminated by a screw hole. Without limitation, further options are conceivable and are not limited to this disclosure.

Figure 12D shows another arrangement similar to that described with respect to Figures 12A and 12B. For simplicity, identical entities in Figure 12D are given the same reference numerals as entities in Figure 12A or Figure 12B. The arrangement of the sensor embedded in the bore of the thin-walled end of the shaft 101 of FIG. 12D notably includes a sleeve 214b different from the sleeve 214a of FIG. 12B . The sleeve of Figure 12D exhibits a gap gr of radial width. The gap may conveniently be filled with air only, or plastic, or other non-magnetic material. The gap gr will help improve the shielding effectiveness of the sleeve 214b. It would be advantageous to adjust the strength of the magnet 206 to the width of the radial gap gr so that the magnetic field of the magnet 206 does not over saturate the sleeve 214b. Such an arrangement will further increase the shielding efficiency of the sleeve 214b.

Figure 12E illustrates another variation of sleeve 214c. The arrangement of Figure 12E is similar to that of Figures 12D and 12B, and like reference numerals are used to designate like elements for the sake of brevity. While the radial gap gr of the sleeve 214b in FIG. 12D extends over the entire length of the sleeve 214b in the axial direction, the radial gap gr of the sleeve 214c of FIG. 12E extends along the length of the thin-walled end portion of the shaft 101. only partially extended. Preferably, the gap gr may extend at least over the length of the sensing element (indicated by x along the axis of rotation, distance da away from the opening of the bore). In this way, the sleeve 214 will effectively at least shield the sensing element from any external magnetic interference. For the sleeve 124b of Figure 12D, the strength of the magnet 206 can be adjusted to the width of the radial gap gr so as not to over saturate the sleeve 214c.

When designing the arrangement of the sensing element(s) within the thin-walled end of the shaft 101 (indicated by x in Figures 10, 12A, 12B, 12D, and 12E), the respective dimensions of the individual elements may be considered, in order to optimize the overall performance of the arrangement.

In general, the inner diameter Di of the bore 101 should be as small as possible, since this will firstly result in a smaller magnet for a given magnet mass (or as an equivalent: the ratio of the available magnetic field to the cost of the magnet material) at (more a) The location of the magnetic field sensing element has a larger magnetic field. Second, the smaller the inner bore diameter Di, the more effective is the shielding from external magnetic fields by the thin-walled end of the shaft 101 and/or the sleeves 214a, 214b, 214c.

If a standard SMD sensor package is used for the sensing element(s) 106 (best seen in Figure 12, where the SMD sensor package 104 is oriented perpendicular to the axis of rotation), the SMD sensor package has lateral dimensions of roughly 5mm x 6mm . If the package is soldered to a small printed circuit board (PCB), and the two are placed inside the shaft, this requires a minimum bore diameter of the magnet 206 of approximately 12mm. Then the bore diameter Di of the shaft needs to be at least 16mm and the outer diameter of the shaft should be at least 18-20mm.

However, for sensor packages with leads, the situation is slightly different, as can be seen from FIG. 13 . FIG. 13 illustrates a cross-sectional view through the shaft 101 within the thin-walled end proximate to the location of the sensing element 106 located inside the bore of the shaft 101 .

Throughout the remainder of this disclosure, a sensor package with leads should be understood as a sensor package in which at least one semiconductor chip is mounted inside the package as shown by the chip in FIG. Covered with a protective cover of mc of molding compound. For sensors with leads, at least two other sensor leads protrude outside the protective cover mc, and the sensor leads are in contact with the chip, so as to supply power to the chip and obtain output signals from the chip. Conveniently, the leads are guided to one side of the package (which is the left side in Figure 13 - the open end on the shaft side).

It should be noted that the leads may enter this protective enclosure mc at its perimeter at several surfaces - but it is useful to bend the leads towards one side, ie towards the open end of the shaft 101 . Of course, it is preferred that all leads protrude at one face of the package. It is also not necessary that the chip(s) be mounted on a lead frame as shown in FIG. 13 . The lead frame may include a die paddle and leads to which the chip is glued or mounted. It will be appreciated that leads are required in order to energize the sensing element and obtain the output of the sensor. Alternatively, simple wires could be used instead of a lead frame. It will of course be understood that a lead frame is optional for all sensing elements discussed throughout this disclosure.

Additionally, the chip can be contacted in various ways: for example, as shown in FIG. 13, by bond wire (bw); or by flip chip assembly on a lead frame; or other means of contact known in the art, which It is not essential to the present disclosure and therefore will not be discussed in detail.

The lower limit for Di is given by the packaging of the magnetic field sensing element(s) and the necessary clearance between the packaging and the bore of the magnet 206 . The smallest possible semiconductor chip size in the radial direction is about 1 mm. This gives a package size of 2.5mm in the radial direction. Accordingly, the minimum bore diameter of the magnet is 3 mm, and thus the minimum bore diameter Di of the thin-walled end of the shaft is 5 mm. In order to maintain the mechanical stability of the shaft, the minimum outer diameter of the shaft is 6mm.

It should be noted that in Figure 13, the magnetic field sensing element 106 preferably detects the orientation of the magnetic field vector projected onto a plane perpendicular to the z-axis. The chips are typically arranged parallel to the z-axis. As a result, the projection of the magnetic field vector onto a plane perpendicular to the z-axis can be decomposed into x and y components, where the y component is in the plane of the chip and the x component is normal to the chip.

If you now decide to use a Cartesian coordinate system with (x,y,z) axes. As a result, magnetic field sensing element 106 must be able to detect the angle between the x and y components of the magnetic field generated by magnet 206 . This is according to tan(angle) = Bx/By angle out of plane (since x is perpendicular to the plane of the chip). Ordinary magnetoresistive elements only detect in-plane angles (ie, the angle between the y and z components of the magnetic field according to tan(angle)=By/Bz). Out-of-plane angles can be detected by a combination of at least one Hall plate and a vertical Hall effect device.

It should also be understood that the placement of the sensing element 106 in the bore should be as symmetrical as possible with respect to the magnet 206 . On the same principle, care should be taken to place the magnets 206 in the holes as symmetrically as possible.

FIG. 14A illustrates a cross-sectional view of the thin-walled end of shaft 101 with cylindrical magnet 206 . It should be noted that Figure 14A, like other figures referenced herein, may not be drawn to scale. The position of the sensing element 106 is indicated by the intersection along the z-axis. Indeed, in the setup of Figure 14A, the location of the sensing element 106 is chosen as the origin. The magnet 206 may be placed symmetrically in the z direction about the sensor position x. For such placement, length S1 is equal to S2. If the opening of the magnet 206 is also concentric with the z-axis, the distance S5 is equal to the distance S6, as shown in Figure 14A. However, distance S7 may not be equal to distance S8 of FIG. 14A if the opening of the magnet is not concentric with the outer perimeter of magnet 206 . It will also be understood that S5 may not be equal to S6' if the inner bore of magnet 206 and/or the perimeter of magnet 206 may be elliptical in shape, or non-circular.

Preferably, as many of the above mentioned equations as possible should be substantially valid, ie S1=S2, S3=S4, S5=S6, and S7=S8. The motivation for satisfying as many equations as possible is the fact that the highest possible level of field uniformity of the magnetic field can be achieved. In other words, if the above equation is satisfied, then the maximum number of spatial derivatives of the magnetic field will vanish at sensor position x. As a result of the vanishing magnetic field derivative, (assembly) tolerances in the direction of the vanishing magnetic field derivative have no influence on the angular measurement of the sensor element 106 . Those of ordinary skill in the art will appreciate that the above symmetry considerations are made under the assumption of a substantially uniform magnetization of the magnet 206 .

14B-14D illustrate a variation of the length S3+S4 of the hole around the sensor position x and the thin-walled end of the shaft 101 with the magnet 206 . For the sake of brevity, the same reference numerals are used to refer to the same elements.

In FIG. 14B the hole terminates in a tapered tip, while the hole of FIG. 14C tapers from inner diameter Di to a minimum diameter Dm, while instead the hole of FIG. 14D changes from inner diameter Di to a minimum diameter Dm creating a shoulder. One of ordinary skill in the art will appreciate the different ways of achieving the hole terminating at the end facing away from the opening (depicted on the right in the figure).

It will be noted that so far the thin-walled bore of the shaft 101 , the magnet 206 and the bore of the magnet have been considered circular when viewed along the z-axis. A very large number of shapes are possible for these elements, and only a selection thereof will be discussed below in connection with Figures 15A-15I. These figures each illustrate a sectional view into the bore of the thin-walled end of the shaft in a plane perpendicular to the z-axis of rotation.

Fig. 15A shows a cross-section of a shaft 101 with a circular outer perimeter, a circular hole, and a magnet 206 with both a circular outer perimeter and a hole, wherein all circular holes and/or perimeters are concentric with the axis of rotation z.

In FIG. 15B, the outer periphery of the shaft 101 is cylindrical, and the hole of the shaft 101 is elliptical, and the outer periphery of the magnet is fitted into the elliptical hole. In addition, the hole of the magnet is also elliptical, however, the major and minor axes of the shaft hole may not coincide with the major and minor axes of the elliptical hole of the magnet 206 . In the arrangement of Figure 15B, the long axis of the outer perimeter of the magnet is in the x direction, while the long axis of the magnet bore is in the y direction. Alternatively, the two major axes may also be parallel, or at any other angle therebetween.

Figure 15C shows a cylindrical shaft 101 with the holes in the thin-walled end of the shaft having a square or rectangular shape. The outer perimeter of the magnet 206 actually matches the shape of the bore of the shaft 101 . The hole of the magnet 206 is circular. Furthermore, all shapes revolve around the axis of rotation z, but this does not limit the disclosure.

Fig. 15D is similar to Fig. 15C, but the holes of the magnets 206 are rectangular or square in shape instead of circular. The outer perimeter of the magnet 206 matches the rectangular shape of the bore of the shaft 101 .

Figure 15E is similar to Figure 15C or 15D. However, in FIG. 15E, the hole of the magnet 206 has a hexagonal shape. Furthermore, the outer perimeter of the magnet 206 matches the rectangle of the bore of the shaft 101 .

In Figure 15F, the bore of the shaft 101 has a pentagonal perimeter, while the bore of the magnet 206 has a hexagonal shape. As before, the inner perimeter of the bore in the shaft matches the outer perimeter of the magnet 206 .

In FIGS. 15G-15H , the bore of the shaft 101 has a different geometry than the outer perimeter of the magnet 206 . In Fig. 15G, the inner perimeter of the thin-walled end of the shaft 101 is circular, while the outer perimeter of the magnet 206 is pentagonal. Such an arrangement leaves some gap between the inner perimeter of the bore of the shaft and the outer perimeter of the magnet 206 . The magnet 206 of FIG. 15G includes hexagonal holes.

In Fig. 15H, the outer perimeter of the shaft 101 is not circular but hexagonal, while the perimeter of the hole at the thin-walled end of the shaft 101 is circular. The outer perimeter of the magnet has a pentagonal shape. For Fig. 15H, the aperture of the magnet is in the shape of a hexagon.

In both cases of Figure 15G and Figure 15H there is a gap between the respective magnet 206 and the bore of the shaft, but this gap has a varying width. It will be appreciated that the magnet 206 may be glued into the bore of the shaft 101, or mechanically secured inside the bore by any suitable mechanism.

In FIG. 15I there is a gap of constant width between the magnet 206 and the bore of the shaft 101 . The gap can be filled with air or plastic, or some other material that is essentially non-magnetic, or some glue, in order to fix the corresponding magnet 206 in the hole of the shaft 101 .

Without limitation, as discussed herein, magnet 206 may be divided into 2, 3, 4, . . . N segments arranged in a symmetrical pattern such that When z is rotated by an angle of 360°/N, it is the same as the original shape, which can also be called N-fold symmetry. For the case of N=4 comprising magnet segments 206a, 206b, 206c, 206d, in Fig. 16 the magnet 206 of N-fold symmetry is shown in section. Such segmented magnets 206 may be produced, for example, by injection molding processes known in the art.

Those of ordinary skill in the art will appreciate that in order to determine the rotational position of the shaft 101 based on the (rotating) magnetic field at the sensor location, care is taken to ensure that, in particular with respect to the azimuthal direction as the direction of rotation of the shaft 101, The position of magnet 206 is well defined within the bore of 101 . To this end, it is convenient to provide one or more slots 205a, 205b and 205c on the outer periphery of the magnet 206 . The slots may be filled with glue, which is used to glue the magnets in the holes of the shaft. The slots 205 a , 205 b , 205 c may also have the purpose of receiving the thermo-mechanical strain of the magnet 206 inside the bore of the shaft 101 in order to reduce the mechanical stress on the magnet 206 . This will help avoid breakage of the magnet 206 . Although the slots 205a, 205b, 205c are illustrated in Figure 17 as slots for the magnet 206, the slots may alternatively or additionally be provided on the inner perimeter of the bore (not shown in Figure 17).

FIG. 18 illustrates a further option to guarantee a defined azimuthal position of the magnet 206 located within the shaft 101 . As a further option, it is also possible to introduce some unique asymmetry into the magnet and the shaft, which acts as a wedge 207 defining the azimuthal position of the magnet 206 relative to the shaft 101 . Furthermore, Figure 18 gives a non-limiting example of such intentional asymmetry. Likewise, the magnets can be in the shape of a frustum combined with the cooperating shape of the hole located inside the shaft 101 .

FIG. 19A illustrates another embodiment of a magnet 206 positioned within a shaft 10 having an outer diameter D. As shown in FIG. Although the axial bore of the shaft 10 has a constant inner diameter 2×S4, and the magnet 206 has a corresponding outer diameter, the inner diameter of the magnet 206 varies from 2×S5 to 2×S3 along the axial direction z, where S3< S5 or S3>S5 (not shown).

FIG. 19B illustrates another variation of magnets 206 positioned within shaft 101 of outer diameter D. FIG. For the exemplary embodiment of Fig. 19B, the inner diameter of the hole tapers from 2xS4 to 2xS6. Accordingly, the outer diameter of the magnet 206 located within the bore corresponds to the inner diameter of the bore extending along the axis of the magnet 206 . It will be noted that the tapered shape of the inner diameter of the bore and the outer diameter of the magnet 206 can be chosen to place the magnet 206 in the bore at a desired axial position, that is, around the sensor indicated by the cross in FIG. 19B . Sensitive points of the arrangement. Unlike the embodiment shown in FIG. 19A , for the embodiment of FIG. 19B no further measurements may be required to arrange the magnets within the holes in the desired positions along the axial direction z. Unlike the embodiment of FIG. 19A , it may be sufficient to slide the magnet 206 into the hole until the magnet stops its travel in the axial direction z when it reaches the desired axial position in which the outside of the magnet 206 is in contact with the inside of the hole. fit, as indicated in Figure 19B.

FIG. 20 illustrates another implementation of a magnet 206 located within the bore of the shaft 101 . However, the inner diameter of the hole includes a step or shoulder which changes the inner diameter of the hole from 2×S4 to 2×S6, where S6<S4. Clearly, the shoulder provides an abutment for limiting the axial mobility of the magnet 206 in the z-direction.

It will be appreciated that, as discussed herein, any sensor and/or magnet arrangement located within the bore of the shaft is of particular interest in measuring the angular position of the engine's drive shaft or rotatable shaft. Conceivable examples are the drive shaft of an internal combustion engine, the drive shaft of any powertrain/drive mechanism system, or, as non-limiting examples, the drive shaft of an electric motor used in an electric vehicle. It should be understood that rotatable shafts considered in this disclosure are configured to transmit torques of up to several hundreds or even thousands of Newton meters Nm. Accordingly, the shaft 101 contemplated within this disclosure needs to be sufficiently torsional rigid in order to reliably transmit such high torques.

Those of ordinary skill in the art will also appreciate that there may be substantial space constraints within, for example, the engine compartment of an electric vehicle. In order to control the electric motor of such a vehicle, the angular position of the drive shaft needs to be known with a high degree of accuracy. According to the prior art, this task is accomplished using a resolver, a mechanical extension of the drive shaft that is to indicate the angular position of the shaft. Obviously, such a resolver requires extra space within the engine compartment as a trade off.

In addition, the accuracy of the angular position indicated by the resolver is dependent on accurately mounting the resolver of the extended drive shaft 101 . Any deviation or tolerance in the position of the resolver relative to the drive shaft will degrade the accuracy of the angular position of the drive shaft indicated by the resolver elements. The advantages of the end of the shaft comprising a hole in the axial direction of the drive shaft and of the hole containing the angle sensing element over the resolver solutions known in the art are also mainly for internal combustion engines, such as for example by such internal combustion engines in powered cars.

Those of ordinary skill in the art will readily appreciate that for a drive shaft 101 that transmits high torque motion, there are typically significant assembly tolerances for resolvers. These tolerances may be caused by static or dynamic deformation of shafts, positioning tolerances of related mechanical parts, or similar resolver elements.

Static deformation of the drive shaft 101 may be caused by any deterioration of the shaft or an object hitting the drive shaft itself.

Dynamic deformations of the drive shaft may be caused by an unbalance of the drive shaft, for example due to deformation, causing additional moments of inertia due to such deformation. Obviously, such static or dynamic deformations will be present in the resolver elements and deteriorate the achievable accuracy of the angular position indicated by the resolver elements.

Static deformation of the resolver elements can likewise be caused by objects hitting the resolver and deforming it. Such deformation could potentially offset the resolver relative to the axis of the drive shaft, to name just one example. Such deformation can also unbalance the resolver, which causes moments of additional inertia during rotation of the resolver with drive shaft 101 , which may actually support further deterioration of the resolver and/or drive shaft 101 .

Those of ordinary skill in the art will appreciate that heavy duty roller bearings are of interest in combination with drive shafts that transmit high torque motion. Such a roller bearing would require a bearing backlash much greater than is typically the case for precision bearings used to transmit motion with low torques of a few Newton meters, even in 1 Newton meter or less. Bearing play in heavily loaded bearings will typically result in increased radial and axial play compared to precision bearings used to transmit low torque motion.

Thus, it will become apparent to those skilled in the art why it is of interest to provide the bearings 202, 212 for driving Shaft 101, as disclosed herein and has been described with respect to Figures 2-5, 12-12B, 12D and 12E.

Those of ordinary skill in the art will also appreciate that it is convenient to use a solid or block shaft according to the present disclosure for the high torque motion transmitted by the drive shaft 101 . With hollow shafts, it may prove difficult to reliably transmit high torque motion because the hollow shaft may not provide the torsional stiffness required for such transmission. The present disclosure achieves more accurate angle measurements by placing an angle sensing element in an axial bore within the end of the drive shaft 101 . Due to the trade-off in mechanical stability, in particular the torsional rigidity of the hollow end can be reduced. Therefore, it may be of interest to provide portions of the drive shaft that are block-shaped and supported by bearings, as can be seen in the embodiments discussed in Figures 12A, B, D and 12E. With such an arrangement, the bearing does not engage the drive shaft in the portion of reduced torsional stiffness due to the axial bore being located in the end of the shaft 101 .

A benefit of the "in-axis" placement of the (angular) sensing element 106 as disclosed herein is the reduction of additional mechanical tolerances caused by static or dynamic deformation, as discussed above with respect to the use of resolvers.

It may be of interest to seal the sensing element 106 from the harsh environment within the engine compartment of the vehicle. Such harsh environments may be caused, for example, by aggressive liquids that would potentially damage the sensing element 106, such as transmission oil, for example, which is commonly known in gearboxes in automobiles running with internal combustion engines, to name a limiting example of. Automotive gearboxes typically include one or more drive shafts 101 for which angular position and/or angular velocity are of interest in order to provide a smooth gear shifting experience.

It should be understood that any disclosure below relating to sensing element 106 is also applicable without limitation to sensor element 104 as discussed above in connection with FIGS. 1-6 and 12 .

Furthermore, it may be of interest to seal the (angular) sensing element 106 against magnetic contamination, which may affect the sensing element 106 based on the principle of magnetic sensing. Magnetic contamination is known in the form of iron filings ubiquitous in many types of machinery. If such magnetic contamination reaches the bore located in the drive shaft 101, the (angular) sensing will be greatly degraded. Therefore, for shaft (angle) sensing as disclosed herein, sealing of the bore may be a concern.

21A and 21B illustrate examples of possible sealing of the sensing element 106 . The arrangement shown in FIGS. 21A and 21B is somewhat similar to the arrangement discussed in connection with FIG. 13 . The housing 212 is used to close the axial hole in the end of the drive shaft 101 . The housing may be made of printed circuit board (PCB) material, but is not limited thereto. Like elements in Figures 21A and 21B are given like reference numerals and therefore should not be discussed in detail again to avoid excessive repetition.

In the embodiment of FIG. 21A , the use of a ring 208 mounted to the surface of the housing 212 is proposed. It may be of interest to engage the ring 208 with the seal 210 . The groove in the azimuthal direction accommodates the seal 210 . The seal 210 may be implemented as a simple O-ring or a sealed bearing known in the art, for example, as a bearing that includes an inner sealing lip (not shown) that seals the interior of the bore from external influences. Without limitation, sealed bearings may also include an outer sealing lip. It should be noted that regardless of the torque transmitted by the drive shaft 101 , the seal 210 can be in contact with most of the transmitted torque in the azimuthal direction. Suitable materials and dimensions for seals to withstand the majority of the transmitted torque in the azimuthal direction are known in the art. A non-limiting example for a seal is an appropriately sized stamped O-ring that seals the interior of the bore from the outside.

It is also of interest to mount the housing 212 so that it does not follow the rotational movement of the drive shaft 101 , but assumes a static position with respect to the azimuthal direction, while sealing the interior of the bore from external influences. The static or stator position of the housing 212 and thus the (angular) sensing element 216 relative to the drive shaft 101 can be achieved using a support structure (not shown).

FIG. 21B discloses another embodiment of a possible seal that seals the sensing element 106 from the exterior of the drive shaft 101 . A washer 214 is employed in connection with housing 212 to surround the circumference of the hollow end of the shaft (ie, drive shaft 101 ). It may be convenient to implement a sealing element bridging the gasket 214 and the drive shaft 101 in the radial direction (as indicated by the vertical direction x in FIG. 21B ). As with the seal of FIG. 21A , the seal 208 may be realized as an O-ring or a bearing comprising at least one sealing lip as is known in the art.

According to the variant of the seal 28 discussed with respect to FIGS. 21A and 21B , it is possible to achieve the rotational movement of the housing 208 following the drive shaft 101 . Such a design for sealing the sensing elements 106 would ease the requirements on the seals 208 since those elements would no longer be exposed to the transmitted torque but would instead move with the drive shaft 101 . It should be noted, however, that for such an arrangement, an additional sealing element 210 would be required, enclosing the portion of the PCB that traverses the housing 212 . This is taken care of in order to ensure that the (angular) sensing element 106 is in a substantially fixed angular position relative to the rotatable drive shaft 101 .

While the shaft-integrated or "in-shaft" arrangement of the (angular) sensing element 106 within the end of the drive shaft 101 helps reduce radial and/or axial assembly tolerances compared to arrangements employing a resolver, These assembly tolerances still exist for in-axis arrangements, but at reduced levels. That is to say, for a resolver with an eccentricity of say 0.5 mm relative to the axis of rotation of the drive shaft, the angular error achieved with the resolver will be greater than for a setup with an eccentricity of 0.5 mm of the magnet relative to the axis of rotation. Angular error achieved by in-axis arrangement.

One option is to employ a magnet arrangement 206 with a magnetic field of high uniformity in order to further reduce the degrading effect of radial and/or axial fitting tolerances of the in-shaft arrangement of the angle sensing element 106 located in the shaft 101 . It should be understood that high uniformity magnets may be used with any of the in-axis magnet arrangements 206 as disclosed herein.

FIG. 22A illustrates a first example of such a high uniformity magnet arrangement 206 . In Fig. 22A, a cross-sectional view of a magnet arrangement is shown. The crosses in Figure 22A indicate positions that correspond to the position of the axis of rotation of the drive shaft once the magnets are disposed within the bore of the drive shaft (not shown). The magnet arrangement of FIG. 22A includes eight magnetic members arranged to form an octagon-shaped magnet ring as a non-limiting example. For each of the magnetic members, the direction of the magnetizations 206-1 to 206-4 is indicated. With such an arrangement of magnetic members, a substantially uniform overall magnetic field 207 will be formed inside the magnetic ring, while outside the ring-shaped magnet arrangement 206 there may be very little or virtually no magnetic field present. Such magnet arrangements are known in the art as Halbach magnets. It may be convenient to glue the individual magnet elements 206 together either before or after magnetization of each segment. Any other way of arranging the magnet elements 206 may be used instead, as long as the arrangement will not substantially interfere with the uniformity of the magnetic field within the ring structure.

Those familiar with the Halbach-type magnet arrangement 206 will appreciate that the axial extension of the Halbach magnet arrangement 206 is preferably greater than the radially inner diameter of the Halbach-type magnet, and even more preferably greater than the radially outer diameter of the Halbach-type magnet. path. Such dimensions typically contribute to improved magnetic field uniformity in radial and similar axial directions.

FIG. 22B illustrates another exemplary embodiment of a Halbach-type magnet 206 in cross-sectional view. It will be noted that the magnet 206 of FIG. 22B comprises a single member with non-uniform magnetization that is slightly balanced in the cross-section shown so that most of the flux lines are concentrated at the center of the magnet 206, whereas in ring-shaped magnets There is virtually no magnetic field on the outside. The advantages of such a Halbach-type arrangement for magnets 206 as discussed with respect to Figures 22A, 22B are twofold:

First, the sensing element 106 is less sensitive to radial and/or axial assembly tolerances, for such displacements the sensor will be substantially invisible to the magnetic field (direction) in the presence of such assembly tolerances. to change, or to see very little change. Thus, it becomes easier to place more than one (angular) sensing element 106 in the region of a substantially uniform magnetic field 207 (as shown in Figures 22A-C). More than one sensing element 106 will then see the same magnetic field 207, which may be of concern when creating redundant and/or dissimilar magnetic (angular) sensing systems. Distinct magnetic (angular) sensing systems measure the magnetic field 207 with more than one sensing element, each sensing element employing a different, i.e. dissimilar, sensing principle, for example, the first using a GMR sensor, the second using a Hall sensors, as a non-limiting example.

In the case of a (transient) disturbance, more than one distinct sensing element will respond to the (transient) disturbance differently due to their distinct sensing principles. Thus, one of ordinary skill in the art will appreciate that (transient) disturbances will become apparent when more than one distinct sensing element is employed. Instead, any sensed data due to (transient) disturbances will become unnoticeable when only a redundant more than one sensing element is used, all using the same, i.e., non-distinct sensing elements. sense principle. For the mere excess of more than one sensing element, all sensing elements will show substantially the same sensing value, which is caused by the same (transient) disturbance - also referred to as due to (transient) disturbance common cause failure.

As a second advantage of the Halbach-type magnet 206, the chamber located outside the magnet 206 is substantially free of any magnetic field, which will reduce any magnetic interference projected from the magnet 206 to any magnetically sensitive structures surrounding the magnet 206 and thus the drive shaft 101 . Also, because the magnet does not apply a magnetic field to the shaft surrounding it, eccentric mounting of the magnet inside the bore of the ferrous shaft does not result in uniformity of the magnetic field on the sensing element at the center of a Halbach-type ring magnet deterioration.

The Halbaeh-type magnet 206 of FIG. 22B can be formed as a single piece using some molding technique or magnetization technique to achieve a non-uniform magnet, as described in US 14/812907 on the applicant's filing date of July 29, 2015. As explained in detail in an earlier filed patent application, which application is hereby incorporated in its entirety.

Figure 22C illustrates a cross-section of another Halbach-type magnet 206, where the magnetization within the ring magnet changes almost continuously, while the magnetic field inside the ring shows a very high degree of uniformity.

Although methods and variations thereof are described and illustrated below as a series of acts or events, it will be appreciated that the illustrated order of such acts or events is not to be construed in a limiting sense. For example, some acts may occur in different orders and/or concurrently with other acts or events than those described and/or illustrated herein. Additionally, not all illustrated acts may be required to implement one or more aspects or embodiments disclosed herein. Furthermore, one or more actions depicted herein may be performed in one or more separate actions and/or stages.

It is to be appreciated that the claimed subject matter can be implemented as a method, apparatus, or article of manufacture using standard programming and/or engineering techniques to produce software, firmware, hardware, or any combination thereof, to control a computer to implement the disclosed (eg, the systems/devices shown in Figures 1, 2, etc. are non-limiting examples of systems that can be used to implement the methods above). The term "article of manufacture" as used herein is intended to cover a computer program accessible from any computer-readable device, carrier, or media. Of course, those skilled in the art will recognize many modifications may be made to this configuration without departing from the scope or spirit of the claimed subject matter.

The sensor arrangement includes a sensor element and a magnet module. A sensor element is configured to measure a magnetic field and is positioned within the shaft. The shaft is configured to shield the magnet module and sensor element. The magnet module is configured to generate a magnetic field. A sensor element is positioned at least partially within the shaft.

Another sensor arrangement includes a sensor module, a housing and a shaft. The sensor module is configured to measure a magnetic field. The housing has a module opening and a housing recess. A sensor module is positioned within the module opening. The shaft is coupled with the shaft recess and has a magnet module configured to generate a magnetic field. The shaft is configured to shield the magnet module and the sensor module.

An integrated sensor device includes a sensor module, housing and magnet module. The sensor module is configured to measure a magnetic field. The housing has a module opening and a shaft recess and is configured to shield the sensor module. A sensor module is positioned within the module opening. A magnet module is positioned within the shaft. The shaft is coupled with the shaft recess. The magnet module is configured to generate a magnetic field. The shaft is configured to shield the magnet module.

A sensor system is disclosed having a sensor module, an interface and a control unit. A sensor module is located within the housing and has a sensor element configured to provide a measurement of the magnetic field. The housing shields the sensor module from one or more interferences. An interface is coupled to the shielded sensor module and is configured to communicate magnetic field measurements from the shielded sensor module. The control unit is configured to determine angle information based on the magnetic field measurements.

A method of operating a sensor device is disclosed. A sensor module is configured or positioned within the housing. The sensor module is shielded from one or more disturbances by the housing. The shaft is configured with a shaft recess. A magnet module is positioned within the shaft recess. Shield the magnet module from one or more disturbances by the shaft. A magnetic field is generated by a magnet module. The magnetic field is measured by the sensor module.

In particular, with respect to the various functions performed by components or structures (assemblies, devices, circuits, systems, etc.) described above, terms (including references to “means”) used to describe such components are intended to correspond to (unless otherwise indicated) any component or structure that performs the specified function of the described component (e.g., which is functionally equivalent), even if not structurally equivalent to performing the present invention in the exemplary embodiments described herein The exposed structure of the function. Additionally, although a particular feature of the invention may have been disclosed with respect to only one of several embodiments, such a feature may be combined with one or more other features of other embodiments, since for any given or particular In terms of application, it is desirable and advantageous. Moreover, to the extent the terms "comprises", "comprising", "has", "containing", "with" or variations thereof are used in the detailed description and claims, such terms are intended to is inclusive in a manner similar to the term "comprising".

Claims (19)

1. a kind of transducer arrangements, including：

Rotatable drive shaft, extends along rotation axiss and includes hole, and this hole is prolonged along rotation axiss from the first end face of this axle Stretch；

Magnetic body module, is arranged in this in the hole and is coupled with drive shaft, and this magnetic body module is configured to generate magnetic in this in the hole ?；And

Sensing element, is configured in response to the rotation in the rotary sensing magnetic field of drive shaft.

2. arrangement according to claim 1, wherein, sensing element has sensitive spot, and this sensitive spot is arranged in the hole, and And it is exposed to rotating excitation field.

3. arrangement according to claim 1, also includes sealing member, and this sealing member can be coupled with drive shaft, to cover this hole, This sealing member will be arranged in the sensing element in the hole portion and the external discrete in this hole.

4. arrangement according to claim 3, wherein, sealing member is coupled with the side face of the end of drive shaft.

5. arrangement according to claim 3, wherein, sealing member is coupled with the first end face of drive shaft.

6. arrangement according to claim 1, wherein, drive shaft is configured to transmit at least tens of Newton meters, preferably The high torque (HT) of hundreds of Newton meter.

7. arrangement according to claim 1, wherein, drive shaft is configured to transmission rotary motion and is used for advancing vehicle.

8. arrangement according to claim 1, wherein, sensing element is implemented as the semiconductor device including at least one tube core Part.

9. arrangement according to claim 1, wherein, magnet arrangement is provided in the periphery being mainly contained in magnet arrangement Magnetic field.

10. arrangement according to claim 1, wherein, drive shaft includes shielding the soft magnetism of magnetic disturbance to sensing element or contains The material of ferrum.

11. arrangements according to claim 9, wherein, magnet arrangement size in the axial direction is more than the internal diameter of magnet arrangement, The external diameter that preferably more than magnet is arranged.

12. arrangements according to claim 9, wherein, magnet arrangement is implemented as solid memder.

13. arrangements according to claim 9, wherein, in substantially tubular shape, it is included positioned at magnet cloth magnet arrangement Being uniformly distributed of the magnetic flux in central area put.

14. arrangements according to claim 1, also include locking mechanism, and this locking mechanism is configured in determining vertically Magnet arrangement is locked in the hole portion by the adopted position place of putting.

15. arrangements according to claim 1, also include locking mechanism, and this locking mechanism is configured to respect to axial direction Definition azimuth position by magnet arrangement be locked in the hole portion.

16. arrangements according to claim 1, wherein, the internal diameter in hole is first straight at positioned at the first end face of drive shaft Footpath tapers into the Second bobbin diameter less than the first diameter.

17. arrangements according to claim 3, wherein, sealing member includes bearing, the bearing of sealing sealing.

18. arrangements according to claim 3, wherein, sealing member is fixedly arranged into relative drive shaft.

19. arrangements according to claim 1, wherein, magnet is magnetic ball.