Sensor assembly for determining rotation about an axis and linear movement parallel to the axis

Abstract

The present disclosure relates to a sensor assembly (200) for determining rotation about an axis (160) and linear movement parallel to the axis (160). The sensor assembly (200) includes a magnetic structure (220), the magnetic structure (220) including a north pole (222) radially displaced from the axis (160) and a south pole (224) radially displaced from the axis (160) and opposite the north pole (222). The north pole (222) and the south pole (224) of the magnet (220) extend radially in the direction of the axis (160) at the axial ends of the sensor assembly (200). The sensor assembly (200) further includes at least one sensor element (230, 330) that is radially sensitive to the magnetic field between the north pole (222) and the south pole (224).

Description

Technical Field

[0001] Examples of the present disclosure relate to a sensor assembly for determining rotation about an axis and linear movement parallel to the axis, particularly for a transmission mechanism. Background Art

[0002] The controls typically provided in a vehicle are for a transmission device that shifts the vehicle gearbox. An automatic transmission includes a limited number of gear selections, such as park, reverse, neutral, and drive, and their variants. In some automatic transmissions, a handle or a shift mechanism is provided, where the driver operates the vehicle by moving the position of the handle in a pattern to switch the gear of the transmission.

[0003] The transmission device in a vehicle is increasingly designed as a shift-by-wire system. Different from a conventional transmission device, the shift-by-wire system does not have a mechanical connection to the vehicle gearbox. Instead, it is electrically connected to an actuator system for controlling the gearbox by changing the gear or drive mode. Without the limitation of a mechanical connection, the actuation type, force, stroke, and locking can be designed to obtain a better user experience, and the transmission device can be placed as needed. In addition, the workload of installing or adopting the transmission device to other platforms is reduced. The absence of a mechanical connection to the gearbox also results in less noise in the vehicle cab.

[0004] The shift-by-wire system typically has a control unit that detects the position of the handle by processing the data of a sensor assembly, mechanically locks the non-permissible gears, and lights up the symbols for engaging the gears if provided. The sensor assembly may include a mechanical switch that conducts or turns off in response to a change in the handle position. However, mechanical switches are often expensive, may wear and corrode, and may also fail. Since the gearbox is classified as related to vehicle operation safety, the sensor assembly meets certain limiting conditions, such as ISO 26262 requires the sensor assembly to have high reliability. Summary of the Invention

[0005] The subject matter of the independent claims addresses the need for improvement. In addition, possible advantageous embodiments are addressed by the dependent claims.

[0006] According to a first aspect of the present disclosure, there is provided a sensor assembly for determining rotation about an axis and linear movement parallel to the axis. The sensor assembly includes a magnetic structure that includes a north pole radially displaced from the axis and a south pole radially displaced from the axis and opposite to the north pole. The north and south poles of the magnet extend radially in the axial direction at the axial ends of the sensor assembly. The sensor assembly further includes at least one sensor element that is radially sensitive to the magnetic field between the north and south poles.

[0007] The sensor assembly can sense rotation and linear movement contactlessly via a magnetic field and can thus operate with low wear. The sensor assembly can be part of the handle of a shift-by-wire system in a vehicle. The driver of the vehicle can rotate or push / pull the movable part of the handle to change gears or select a driving mode.

[0008] The magnet can rotate around an axis and relative to the sensor element and can move linearly relative to the sensor element and parallel to the axis.

[0009] The sensor assembly can also include a metal shield located at the outer surface of the magnet. The outer surface may not face the sensor element.

[0010] In this way, the sensor assembly can be shielded from electromagnetic interference, such as that originating from vehicle controllers or actuators. Additionally, the magnetic field can be amplified.

[0011] At least one sensor element can be a three-dimensional Hall sensor.

[0012] Using a three-dimensional Hall sensor, the number of required sensor elements can be reduced and the accuracy of the sensor assembly can be increased.

[0013] The sensor assembly can also include a second sensor element sensitive to the magnetic field.

[0014] If one sensor element fails, the second sensor element can ensure redundancy.

[0015] The first sensor element and the second sensor element can be located at equal radial distances from the axis on opposite sides of the axis.

[0016] The magnetic structure can be shaped as a hollow cylinder closed at the axial ends.

[0017] Half of the hollow cylinder can form the north pole and the other half of the cylinder can form the south pole.

[0018] According to a second aspect of the present disclosure, there is provided a shift mechanism for controlling a transmission. The shift mechanism includes the sensor assembly as described above.

[0019] The shift mechanism can also include a handle coupled to the magnet such that rotation of the handle for selecting a driving mode rotates the magnet. The handle can also be coupled to the magnet such that pushing the handle or a part thereof causes linear movement of the magnet parallel to the axis.

[0020] According to a third aspect of the present disclosure, there is provided a vehicle including the automatic transmission as described above and a shift mechanism for controlling the automatic transmission. Description of the Drawings

[0021] Some examples of the device and / or method will now be described by way of example only and with reference to the accompanying drawings, where

[0022] Figure 1 a handle for controlling a gearshift mechanism of a gearbox is illustrated;

[0023] Figure 2 a first embodiment of a sensor assembly for determining rotation about an axis and linear movement parallel to the axis is illustrated;

[0024] Figures 3a to 3c illustrate a second embodiment of a sensor assembly for determining rotation about an axis and linear movement parallel to the axis. Detailed Description

[0025] Some examples will now be described in more detail with reference to the accompanying drawings. However, other possible examples are not limited to the features of these embodiments described in detail. Other examples may include modifications of the features as well as equivalents and alternatives of the features. In addition, the terms used herein to describe certain examples should not limit other possible examples.

[0026] Throughout the description of the drawings, the same or similar reference numerals refer to the same or similar elements and / or features, which may be the same or implemented in a modified form while providing the same or similar functions. For clarity, the thickness of lines, layers, and / or regions in the figures may also be exaggerated.

[0027] Unless explicitly defined otherwise in a separate case, when two elements A and B are combined using "or", this should be understood to disclose all possible combinations, i.e., only A, only B, and A and B. As an alternative wording for the same combination, "at least one of A and B" or "A and / or B" may be used. This equivalently applies to combinations of more than two elements.

[0028] If a singular form such as "a", "an", and "the" is used and there is no explicit or implicit definition that only a single element is mandatory, further examples may also be implemented using multiple elements to achieve the same function. If the following describes a function as being achieved using multiple elements, further examples may implement the same function using a single element or a single processing entity. It should also be understood that the terms "include", "including", "comprise", and / or "comprising", when used, describe the presence of the specified features, integers, steps, operations, processes, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, processes, elements, components, and / or groups thereof.

[0029] One object of the present disclosure may be to provide an improved concept for determining the position of a handle (such as a knob) or parts thereof.

[0030] For example, the handle may be part of a gearshift mechanism for controlling a transmission in a vehicle. The handle may be located in the vehicle cab accessible to the vehicle driver (usually in the center console or dashboard of the vehicle). The handle may include a shift pattern diagram indicating at which positions the handle or parts thereof can be moved to select a particular gear or drive mode. The current position of the handle or parts thereof may indicate the current gear selection to the driver. The driver of the vehicle may want to change the gear or drive mode of the vehicle, for example, when changing from park to drive. The driver can thus manually change the current position of the handle or part thereof to a position indicating the desired gear or drive mode (according to the shift pattern).

[0031] To change the position, the driver can, for example, rotate or push / pull a movable part of the handle. In this way, the driver can select the desired gear or drive mode. In a by-wire gearshift system, there may be no mechanical connection from the handle to the transmission. Instead, a sensor assembly integrated inside the handle can determine the change in the handle position to indicate the gear or drive mode. In other words, the sensor assembly is capable of determining the movement of the handle, in particular the rotation or linear movement (push / pull) of the handle. For this purpose, the sensor assembly may include a magnetic structure and a sensor element sensitive to a magnetic field. The movement of the handle may also cause the movement of the magnetic structure. This may change the magnetic field sensed by the sensor element. The sensor element can communicate a signal (analog or digital) indicating the magnetic field to a control unit. The control unit can process the signal and can correspondingly control an actuator that mechanically switches the gear or drive mode as required.

[0032] Alternatively, the handle may be part of a stalk module surrounding the vehicle steering wheel. In this case, the position of the handle or parts thereof can be used to control the windshield wipers, lights, heating of the vehicle or to perform other vehicle functions.

[0033] Figure 1 A top view of a handle 100 for a gearshift mechanism for controlling an (automatic) transmission of a vehicle is illustrated. The handle 100 is an elongated knob, at one end of which a rotatable part 110 surrounds approximately one-third of the handle 100. The rotatable part 110 is cylindrical and is mounted at one end to a fixed part 120 of the handle 100, the fixed part 120 constituting the remaining two-thirds of the handle 100. A pushable part 130 of the handle 100 projects from a recess of the rotatable part 110 at the opposite end of the rotatable part 110.

[0034] The shift pattern 140 is shown on the stationary part 120. The shift pattern 140 includes four options which may refer to the normal drive modes of an automatic transmission: N (Neutral), when no drive is applied to the vehicle wheels while the engine is running; P (Park), when the transmission can be mechanically locked in the park position, for example via a parking pawl; R (Reverse), for reverse movement; and D (Drive), for forward movement with automatic gear operation.

[0035] At the second end of the handle 100, the elbow piece 150 projects from the stationary part 120. The elbow piece 150 can serve as a fixing element for the handle 100 when integrated into the center console, for example.

[0036] The rotatable part 110 can be manually rotated about the axis 160, which can be the longitudinal axis passing through the center of the handle 100. There can be three positions 170, 172, 174 into which the rotatable part 110 can snap (the points 170, 172, 174 can indicate where the upper side orientation of the rotatable part 110 is located). In the neutral position 170, the rotatable part 110 can indicate the above-mentioned neutral mode N. Rotating the rotatable part 110 about the axis 160 in one direction (e.g., 30 degrees) can cause the upper side of the rotatable part 110 to be oriented to the drive position 172. The drive position 172 can be related to the above-mentioned drive mode D. Starting from the neutral mode N and rotating the rotatable part 110 in the other direction about the axis 160 (e.g., 30 degrees) can cause the upper side of the rotatable part 110 to be positioned towards the reverse position 174. The reverse position 174 can be associated with the above-mentioned reverse mode R. When the vehicle is moving forward, rotating the rotatable part 110 to the reverse position 174 can be blocked by a mechanical lock within the rotatable part 110.

[0037] When the rotatable part 110 is in the drive or reverse positions 172, 174, the pushable part 130 can be mechanically locked. When the rotatable part 110 is in the neutral mode 170, the pushable part 130 can be released. When released, the pushable part 130 can be manually pushed further into the interior of the rotatable part 110 (e.g., when the driver wants to park the vehicle). Inside the rotatable part 110, the pushable part 130 can snap into a catch. This state can indicate the above-mentioned park mode. A second push of the pushable part 130 can open the catch and release the pushable part 130 (e.g., when the driver wants to start the vehicle's engine and change from the park mode to the neutral mode). In other embodiments, the handle 100 can be part of a manual (non-automatic) transmission and display gears on the shift pattern 140. More (or fewer) positions can be provided to which parts of the handle 100 can be rotated or moved.

[0038] In order to translate the movement of the handle 100, such as rotating the rotatable part 110 or pushing the pushable part 130, into a gearbox change, a gearshift mechanism can control the gearbox based on the movement of the handle 100. For example, when the driver rotates the rotatable member 110 from the neutral position 170 to the drive position 172, the gearshift mechanism can change the gearbox from the neutral mode to the drive mode. Since there may be no mechanical connection from the handle 100 to the gearbox, as in a by-wire shift system, it may be necessary to determine the movement of the handle 100 through a sensor assembly. The signals of the sensor assembly can be used to control an actuator that changes the gear or drive mode of the gearbox. Conventional sensor assemblies can include mechanical switches, a large number of different sensor elements, or may be sensitive to electromagnetic interference.

[0039] Accordingly, the present disclosure can be directed to providing an improved motion measurement concept, particularly for a handle in a vehicle.

[0040] Figure 2A first embodiment of a sensor assembly 200 for determining rotations 210, 212 about axis 160 and a linear movement 214 parallel to axis 160 is shown. The sensor assembly 200 includes a magnetic structure 220 having a north pole 222 radially displaced from axis 160 and a south pole 224 radially displaced from axis 160 and opposite the north pole 222. The north pole 222 and the south pole 224 may be disks or rods elongated along axis 160. The north pole 222 and the south pole 224 extend radially in the direction of axis 160 at the axial ends of the sensor assembly 200. For example, the north pole 222 and the south pole 224 may have elbow members 226, 228, where one elbow member extends parallel to axis 160 and the other elbow member projects toward axis 160. The sensor assembly 200 includes a sensor element 230 that is radially sensitive to the magnetic field between the north pole 222 and the south pole 226. The sensor element 230 may be placed with one side parallel to axis 160, displaced from axis 160, and between the north pole 222 and the south pole 224. The sensor element 230 is capable of sensing several different movements of the sensor element 230 relative to the magnetic structure 220. First, as shown by arrows 210, 212, the sensor element 230 may rotate about axis 160 in two directions (clockwise, counterclockwise) relative to the magnetic structure 220. In this case, the sensor element 230 may sense a change in the magnetic field, such as the angle between the surface of the sensor element 230 and the magnetic field lines 240 of the magnetic field may change. This also occurs when the sensor element 230 may be tilted about axis 160, as shown by arrow 216. Second, as shown by arrow 214, the sensor element 230 may linearly move relative to the magnetic structure 220 and parallel to axis 160. In this case, the sensor element 230 may sense a change in the magnetic field as it moves toward or away from the projecting elbow members 226, 228 of the magnetic structure 220.

[0041] Figures 3a through 3c illustrate a second embodiment of the sensor assembly 200 for determining rotation about axis 160 and linear movement parallel to axis 160. Figure 3a shows a diagonal view of a cross-section of the sensor assembly 200. Figure 3b shows a side view of the cross-section. Figure 3c shows a rear view of the upper portion of the sensor assembly 200. The sensor assembly 200 can be implemented into a handle (such as the handle 100 shown above). The sensor assembly 200 includes a magnet 220 having a north pole 222 and a south pole 224. The magnet 220 is shaped as a hollow cylinder with one end closed (right side in Figures 3a and 3b) and the other end open (left side). The north pole 222 forms one half of the hollow cylinder and the south pole 224 forms the other half of the hollow cylinder. The magnet 220 surrounds the axis 160. The magnet 220 can be bonded ferrite, nickel, or other magnetic material. The magnet 220 can generate a magnetic field that penetrates the hollow interior of the magnet 220. The magnetic field can particularly have magnetic field lines (240) between the north pole 222 and the south pole 224, originating from the north pole 222 and pointing to the south pole 224. A cap 310 covers the outer side of the magnet 220. The cap 310 can be steel or other conductive or magnetic material. The cap 310 can serve as a shield against electromagnetic stray fields from outside the sensor assembly 200. The cap 310 can also increase the magnetic field strength of the magnetic field.

[0042] Inside the hollow interior of the magnet 220, two sensor elements 230, 330 are radially displaced from the axis 160, at an equal distance from the axis 160 and opposite to each other. The sensor elements 230, 330 are respectively mounted on the upper side and the lower side of a printed circuit board 340. The printed circuit board 340 has an elongated extension that protrudes from the open end of the magnet 220 into the hollow interior of the magnet 220. There is a gap between the end of the elongated extension (right side) and the closed end of the magnet. The sensor elements 230, 330 can be sensitive to the magnetic field. The sensor elements 230, 330 can include two-dimensional (2D) or three-dimensional (3D) Hall sensors. A 2D Hall sensor may be able to sense the x and y components of the magnetic field. A 3D Hall sensor may be able to sense the x, y, and z components of the magnetic field.

[0043] The magnet 220 can rotate about the axis 160 relative to the sensor elements 230, 330. In other words, the magnet 220 can be rotatable and the sensor elements 230, 330 can be kept fixed, or the magnet 220 can be kept fixed while the sensor elements 230, 330 can be rotatable. The cap 310 can rotate together with the magnet 220. The rotation of the magnet 220 can correspond to the rotation of the handle 100 or a part thereof. When rotating, the relative positions of the north pole 222 and the south pole 224 relative to the sensor elements 230, 330 can change. The orientation of the magnetic field of the magnet 220 can change accordingly. The sensor elements 230, 330 can sense the change in the relative position of the magnet 220 relative to the sensor elements 230, 330. Thus, the sensor elements 230, 330 can determine the rotation of the handle 100 or a part thereof.

[0044] The magnet 220 can also move relative to the sensor elements 230, 330 parallel to the axis 160. For example, when the pushable part 130 (not shown) of the handle 100 can be pushed, the magnet 220 can move towards the sensor elements 230, 330, thereby reducing the gap between the magnet 220 and the printed circuit board 340. The parallel movement of the magnet 220 can also result in a change in the relative position of the magnet 220, and the change in the relative position can be sensed by the sensor elements 230, 330. Thus, the sensor elements 230, 330 can determine when the pushable part 130 of the handle 100 can be pushed.

[0045] The sensor elements 230, 330 can generate sensor signals indicating the change in the relative position of the magnet 220. The sensor signals can be transmitted to a signal processing unit, which processes the sensor signals, for example, to decide which drive mode to select according to the relative position of the magnet 220. The processed sensor signals can be transmitted to a control unit that can activate the actuator. The actuator can apply the clutch of the gearbox according to the selected drive mode.

[0046] The size and material of the sensor assembly 200 can be optimized to achieve small assembly space, high material savings, and good sensing accuracy. For example, it may be necessary for the magnetic field to have a certain magnetic field strength to be detected by the sensor elements 230, 330. For this purpose, the material of the magnet 220 can be selected accordingly. Since the magnetic field strength weakens as the distance from the magnet 220 increases, it may be necessary to place the sensor elements 230, 330 close to the magnet 220. The gap between the magnet 220 and the printed circuit board 340 can be designed for the convenient actuation stroke of the pushable part 130 of the handle 100.

[0047] In other embodiments of the present disclosure, there may be more or fewer sensor elements (230, 330) than shown in FIGS. 3a - 3c. The sensor elements 230, 330 may be positioned asymmetrically relative to the axis 160. The magnet 200 may be closed at one end (right side) such that the north pole 222 and the south pole 224 of the magnet 220 are at the radial ends of the sensor assembly 200 and radially extend in the direction of the axis 160. The magnet 200 may have different shapes, for example, including two plates that face each other and enclose the sensor elements 230, 330 therebetween as the north pole 222 and the south pole 224. For example, if a shield is not required, the cap 310 may be omitted in other embodiments.

[0048] In summary, the sensor assembly 200 is provided for determining the relative movement of the magnet 220 relative to the sensor elements 230, 330. Sensing using the sensor elements 230, 330 can be low - wear because it can be contactless. It can be applied in the handle 100 or the knob of a wire - controlled shift system. The knob may have rotational and push functions for selecting a gear or a drive mode. Additionally, the cap 310 can provide stray - field robustness. 3D Hall sensors can reduce the number of sensor elements required to sense the relative movement of the magnet 220. Alternatively, the sensor assembly 200 can be implemented in a lever at the roof pillar module of a vehicle.

[0049] Aspects and features related to specific examples in the foregoing examples can also be combined with one or more of the other examples to replace the same or similar features of the other examples or to additionally introduce these features into the other examples.

[0050] It should also be understood that, unless explicitly stated in a separate case or required for technical reasons, the disclosure of several steps, processes, operations, or functions in the specification or claims should not be construed as implying that these operations must depend on the described order. Thus, the foregoing description does not limit the execution of several steps or functions to a certain order. Additionally, in further examples, a single step, function, process, or operation can include and / or be decomposed into several sub - steps, functions, processes, or operations.

[0051] If certain aspects have been described for a device or system, these aspects should also be understood as a description of the corresponding method. For example, the block, device, or functional aspects of a device or system can correspond to the features of the corresponding method, such as method steps. Thus, aspects described with respect to the method should also be understood as a description of the corresponding blocks, corresponding elements, properties, or functional features of the corresponding device or corresponding system.

[0052] The appended claims are hereby incorporated into the detailed description, where each claim may stand on its own as a separate example. It should also be noted that although in the claims, dependent claims refer to a particular combination with one or more other claims, other examples may also include combinations of the subject matter of dependent claims with any other dependent or independent claim. Such combinations are expressly set forth herein unless it is stated otherwise in a particular instance that a particular combination is not intended. In addition, any other independent claim should also include the features of the claim, even if the claim is not directly limited to being dependent on that other independent claim.

Claims

1. A sensor assembly (200) for determining rotation about an axis (160) and linear movement parallel to the axis (160), the sensor assembly (200) comprising: A magnetic structure (220) including a north pole (222) and a south pole (224), the north pole (222) being radially displaced from the axis (160), and the south pole (224) being radially displaced from the axis (160) and opposite to the north pole (222); Wherein the north pole (222) and the south pole (224) of the magnetic structure (220) are at an axial end of the sensor assembly (200) and radially extend in the direction of the axis (160); And At least one sensor element (230, 330) that is radially sensitive to the magnetic field between the north pole (222) and the south pole (224), Wherein the at least one sensor element (230, 330) is mounted to an elongate extension of a printed circuit board (340), Wherein the elongate extension projects from an open end of the magnetic structure (220) and extends into the hollow interior of the magnetic structure (220), and Wherein the magnetic structure (220) is rotatable about the axis (160) and relative to the at least one sensor element (230, 330), and is linearly movable relative to the at least one sensor element (230, 330) and parallel to the axis (160).

2. The sensor assembly (200) according to claim 1, wherein the magnetic structure (220) includes a closed end opposite to the open end of the magnetic structure (220), and Wherein the end of the elongate extension is positioned at a distance from the closed end to enable the magnetic structure (220) to be linearly movable relative to the at least one sensor element (230, 330).

3. The sensor assembly (200) according to claim 1 or 2, further comprising a metal shield (310) at an outer surface of the magnetic structure (220), the outer surface not facing the at least one sensor element (230, 330).

4. The sensor assembly (200) according to claim 1 or 2, wherein the at least one sensor element (230, 330) is a three-dimensional Hall sensor.

5. The sensor assembly (200) according to claim 1 or 2, wherein the at least one sensor element (230, 330) includes a first sensor element (230) sensitive to a magnetic field and a second sensor element (330) sensitive to a magnetic field.

6. The sensor assembly (200) according to claim 5, wherein the first sensor element (230) and the second sensor element (330) are at opposite sides of the axis (160) and at equal radial distances from the axis (160).

7. The sensor assembly (200) according to claim 1 or 2, wherein the magnetic structure (220) is shaped as a hollow cylinder closed at the axial ends.

8. The sensor assembly (200) according to claim 7, wherein a first half of the hollow cylinder forms the north pole (222), and a second half of the hollow cylinder forms the south pole (224).

9. A speed change mechanism for controlling a gearbox, comprising the sensor assembly (200) according to any one of claims 1 to 8.

10. The speed change mechanism according to claim 9 further comprises: A handle (100), the handle (100) being coupled to the magnetic structure (220), wherein, rotation of the handle (100) for selecting a drive mode causes the magnetic structure (220) to rotate; and pushing of at least a part of the handle (100) causes a linear movement of the magnetic structure (220) parallel to the axis (160).

11. A vehicle, comprising an automatic gearbox and a speed change mechanism according to claim 9 or 10 for controlling the automatic gearbox.

Images