Steering angle sensor for determining the steering angle of a steering handle of a motor vehicle

Abstract

Steering device for a motor vehicle, comprising a contact unit (2) configured to establish an electrical connection between at least one component arranged on a steering handle of the steering device and a component located outside the steering device, wherein the contact unit (2) has a housing (22) in which an electrical conductor element in the form of a winding band (24) is located;- a steering angle sensor (1) for determining a steering angle of the steering handle, comprising: - at least one angle sensor (1) comprising - at least one first transmission element (12) configured to cooperate with a second transmission element (21) following a rotation of the steering handle of the motor vehicle, wherein - the second transmission element (21) is at least partially arranged in the housing (22) of the contact unit (2), characterized in that the angle sensor (1) comprises a multiturn sensor device (11) cooperating with the first transmission element (12), wherein the second transmission element (21) at least partially surrounds the winding band (24).

Description

The invention relates to a steering device for a motor vehicle according to claim 1.From the prior art, sensors for determining the steering angle of a steering wheel (the "steering angle" or "steering wheel angle") are known. These previously known steering angle sensors must be arranged at least partially below a contact unit of the steering wheel, which leads to an increased installation space requirement. Such a steering angle sensor is described, for example, in DE 10 2014 102 982 A1. DE 10 2014 210 518 A1 discloses a steering angle sensor for detecting a steering angle of a steering shaft over an angle range of greater than 360°.The problem to be solved by the invention is to provide a steering device with a steering angle sensor which takes up as little additional installation space as possible and can be realized in as simple a manner as possible.This problem is solved by providing a steering device having the features of claim 1. Further developments of the invention are specified in the dependent claims.A steering device for a motor vehicle is then provided, witha contact unit configured to establish an electrical connection between at least one component arranged on a steering handle of the steering device and a component located outside the steering device, whereinthe contact unit has a housing in which an electrical conductor element in the form of a winding strip is located;a steering angle sensor for determining a steering angle of the steering handle, comprising:at least one angle sensor,at least one first transmission element configured to cooperate with a second transmission element following a rotation of the steering handle of the motor vehicle, whereinthe angle sensor has a multiturn sensor device interacting with the first transmission element, whereinthe second transmission element is arranged at least partially in the housing of the contact unit and surrounds the winding tape at least partially.The multiturn sensor device enables the steering angle sensor to be designed as space-saving as possible. Moreover, by using a multiturn sensor device (multi-revolution sensor device) for determining the number of revolutions of the steering handle, a memory for temporarily storing the number of revolutions detected and, accordingly, a continuous voltage supply of the memory can be dispensed with. This increases the operational reliability of a steering device and thus of the entire vehicle, since the absolute steering angle is detected in particular also when the vehicle ignition is switched off. For example, the multiturn sensor device can detect at least two revolutions (i.e. 2×3 360°) of the steering handle, in particular without additional electrical intermediate storage. It is conceivable that up to 50 revolutions can be registered.The steering handle is designed, for example, in the form of a steering wheel which has a steering wheel rim which at least partially revolves around a central region of the steering wheel (in particular a hub). However, it is also conceivable for the steering handle to be another element which can be rotated about a steering axis in order to preset a wheel steering angle. The steering axis is defined in particular by a steering column of the vehicle. However, it is also conceivable that the invention is used in connection with a steer-by-wire steering system which does not have a steering column for mechanically transmitting a rotation of the steering handle to the vehicle wheels.The multiturn sensor device is e.g. a magnetic multiturn sensor device, wherein for example recorded revolutions can be stored in magnetic ways by the multiturn sensor device itself.For example, the multiturn sensor device comprises a magnetizable and / or conductive structure and at least one magnetic element, wherein magnetizable or the conductive structure and the magnetic element are rotatable relative to one another. The multiturn sensor device is designed, for example, such that the magnetizable and / or conductive structure and / or the magnetic element-viewed in a direction perpendicular to a steering axis of the motor vehicle-can be located at least partially next to a receptacle for an electrical conductor element of a contact unit of the vehicle assigned to the steering handle and / or next to the electrical conductor element of the contact unit. The receptacle in which the electrical conductor element is located is formed by a housing or a housing section of the contact unit.The contact unit serves primarily to establish an electrical connection between components of the vehicle (for example a power supply or a controller) which are located outside a steering device and components (for example switches and / or displays) which are attached to the steering handle of the steering device. The electrical conductor element is designed in the form of a conductor strip (winding strip).It is possible for the magnetic element to be connected to the first transmission element in a rotationally fixed manner and to follow a rotation of the first transmission element. It is conceivable that the magnetic element is fastened to an axis of the first transmission element. It is also possible for the magnetic element to be fastened to a housing which is connected to the first transmission element in a rotationally fixed manner. For example, the magnetic element is designed in the form of a disk.The magnetic element is in particular designed in the form of a permanent magnet. The magnetizable and / or conductive structure is, for example, a magnetizable and / or conductive material strip and is in particular arranged at a distance from the magnetic element, so that the latter is rotatable relative to the material strip. In particular, magnetizable and / or conductive structure is mounted in the vehicle in such a way that the magnetic field of the magnetic element acts on it. For example, the magnetizable and / or conductive structure is arranged on a carrier (for example in the form of a printed circuit board) which does not follow a rotation of the first transmission element. During rotation of the first gear element, a rotation also of the magnetic element occurs, so that a rotating magnetic field acts on the magnetizable and / or conductive structure.The magnetizable and / or conductive structure runs, for example, in a spiral shape. It is also conceivable for it to comprise a GMR material (Riesenmagnetowiderstandsmaterial). A rotating magnetic field acting on the magnetizable and / or conductive structure during rotation of the first transmission element can result in a change in positions of magnetic domains of the structure, i.e. of regions between differently magnetized sections of the structure. The magnetizable and / or conductive structure thus stores the number of revolutions of the magnetic field that have taken place. On the basis of the positions of the magnetic domains, the angle of rotation and the number of revolutions made of the magnetic field acting on the structure and thus of the first transmission element can be determined. On the basis of the angle of rotation or the rotations of the first gear element, the angle of rotation or the number of rotations of the second gear element that have taken place, i.e. of the steering handle, can in turn be determined.A multiturn sensor device, which determines a number of revolutions of a magnetic field on the basis of the domain positions, is described in DE 10 2017 104 551 A1. Reference is hereby expressly made to this document with respect to the multiturn sensor device. For example, the multiturn sensor device of the steering angle sensor according to the invention is a sensor described in DE 10 2017 104 551 A1. It is conceivable, for example, for the multiturn sensor device of the steering angle sensor according to the invention to have a sensor according to one of Claims 9 to 13 of DE 10 2017 104 551 A1, wherein the "magnetic strip" mentioned there corresponds to the magnetizable and / or conductive structure mentioned above.It is also conceivable for the magnetizable and / or conductive structure to be part of an integrated sensor circuit. For example, the integrated sensor circuit comprises an activation and / or evaluation electronics, with the aid of which the position of the magnetic element and thus the steering angle and / or the number of revolutions of the steering handle can be determined on the basis of the state (in particular its magnetic state) of the magnetizable and / or conductive structure. It is conceivable for the integrated sensor circuit to be designed in the manner of the sensor component ADMT4001 (Analog Devices). It is also possible that the integrated sensor circuit, as already explained above with reference to the magnetizable and / or conductive structure, is located next to the receptacle for an electrical conductor element of the contact unit of the motor vehicle assigned to the steering handle and / or next to the electrical conductor element of the contact unit.The first transmission element is in particular designed in the form of a gearwheel or a gearwheel segment, i.e. in the form of an element whose toothing at least partially revolves around an axis of rotation.The housing of the contact unit is formed integrally, for example. It is, of course, also possible for this to be a multi-part housing. The housing forms the receptacle for the electrical conductor element, wherein the second gear element is at least partially likewise arranged in this receptacle.The second gear element is in particular designed and arranged such that it at least partially revolves around a steering axis about which the steering handle is rotatable.It is furthermore conceivable for the housing (in particular an upper housing part) to form or have a structure (centring structure) which centres the first transmission element. The structure is formed, for example, in the manner of a pin (connected, for example, in one piece to the housing) or some other raised structure, which is aligned, in particular, along an axis of rotation of the first transmission element and engages, in particular, in a corresponding depression of the first transmission element. Conversely, the first gear element could of course also be provided with a raised structure which engages in a speaking depression of the housing.It is possible that the first gear element is at least partially also arranged in the housing of the contact unit. For example, the housing forms a corresponding receiving region for the first transmission element. It is also possible for the housing of the contact unit to form a first receiving region for the first transmission element and a second receiving region for the second transmission element. The first gear element can of course also be accommodated in a housing separate from the contact unit and in particular this housing forms or has the above-mentioned centering structure.The invention is explained in more detail below on the basis of exemplary embodiments with reference to the figures. The following are shown: FIG. 1 shows a steering angle sensor according to an exemplary embodiment of the invention; FIG. 2 shows the steering angle sensor from FIG. 1 together with a contact unit of a vehicle in an exploded illustration; and FIG. 3 shows the steering angle sensor from FIG. 1 and the contact unit in a partially cut-away plan view.FIG. 1 shows a steering angle sensor 1 according to the invention for detecting a steering angle of a steering handle of a steering device of a motor vehicle, wherein the steering angle sensor 1 comprises an angle sensor having a multiturn sensor device 11 which interacts with a first transmission element in the form of a first gearwheel 12. The multiturn sensor device 11 has a magnetic element in the form of a magnetic disk 111 which is connected to a shaft 112 in a rotationally fixed manner. The first gearwheel 12 is in turn likewise connected to the shaft 112 so that a rotation of the gearwheel 12 is transmitted to the magnetic disc 111. The magnetic disk 111 is located in a housing 113 of the steering angle sensor 1, wherein the first gear 12 is arranged above the housing 113. It is also conceivable that the rotation of the first gearwheel 12 is transmitted to the magnetic 111 via the housing 113.The multiturn sensor device 11 furthermore comprises a magnetizable and / or conductive structure (not recognizable in FIG. 1 ), which is arranged on a carrier in the form of a printed circuit board 114. The printed circuit board 114 is fixed to the vehicle, i.e. it does not follow a rotation of the first gearwheel 12, so that a relative movement between the magnetic disc 111 and the magnetizable and / or conductive structure arises during a rotation of the first gearwheel 12. This relative movement brings about a change in the magnetic properties of the magnetizable and / or conductive structure, which permits conclusions to be drawn about the angle and / or the number of revolutions of the magnetic disc 111, as explained above. It is conceivable for the magnetizable and / or conductive structure to be part of an appropriately configured integrated sensor circuit 115, as likewise already explained above. The sensor circuit 115 is electrically contacted, for example, with the aid of conductor tracks of the printed circuit board 114.The first gear wheel 12 is in engagement with a second gear element in the form of a second gear wheel 21 which belongs to a contact unit 2 (FIGS. 2 and 3 ) of the steering device. The second gearwheel 21 is arranged and designed such that it follows a rotation of the steering handle of the steering device. Accordingly, the rotation of the steering handle is transmitted to the first gear wheel 12 with the aid of the second gear wheel 21, so that the steering angle and / or the number of revolutions of the steering handle can be determined with the aid of the multiturn sensor device 11. For example, the second gearwheel 21 is connected to a steering axle (in particular a steering column) interacting with the steering handle.As shown in FIGS. 2 and 3, the second gearwheel 21 is arranged in a receptacle 23 formed by a housing 22 of the contact unit 2. The first gearwheel 12 projects through a cutout 2121 of a side wall 212 of a housing lower part 211 into the receptacle 23.Furthermore, an electrical conductor element in the form of a winding tape 24 is located in the housing 22 of the contact unit 2. the second gearwheel 21 surrounds the winding tape 24 at least partially, wherein it is conceivable that the winding tape 24 is arranged together with the second gearwheel 21 in the receptacle 23. The multiturn sensor device 11 is designed such that the magnetic disk 111 is located at least partially laterally or radially, i.e. viewed in a direction perpendicular to the steering axis, next to the receptacle 23 and / or the winding tape 24. For example, the magnetic disk 111 is arranged next to the contact unit 2. It is also conceivable for the sensor circuit 115 to likewise be located at least partially laterally next to the receptacle 23 and / or the winding tape 24. It is also possible for the sensor circuit 115 to be located completely outside the contact unit 2.The multiturn sensor device 11 and the first gearwheel 12 are accommodated in a further housing 13, wherein the printed circuit board 114 is at least partially located in a housing lower part 131 and the first gearwheel 12 is at least partially arranged in a housing upper part 132. It is possible for the housing 13 (for example the upper housing part 132) to be connected at least partially integrally to the housing 22 of the contact unit 2. It is of course also conceivable for the housing 13 to be formed completely separately from the housing 22 of the contact unit and to be located next to the housing 22 of the contact unit 2 and not below the contact unit 2. The upper housing part 132 and the lower housing part 211 are in particular made of plastic, for example by injection molding.In addition, a centering structure can be formed or integrally formed on the upper housing part 132, with which centering structure the first gearwheel 12 is centered. For example, the (in particular raised) structure engages with a corresponding, central structure of the first gearwheel 12. It is conceivable that the centering structure is a pin which engages in a depression 121 of the first gearwheel 12. Conversely, it is of course also possible for the first gearwheel 12 to form a raised structure which engages in a centring structure, formed as a depression, of the upper housing part 132. The centering structure is connected, for example, integrally to the upper housing part 132 or the gearwheel 12. However, it is also conceivable that this is a separate part (e.g. a pin) which is connected to the upper housing part 132 or the gearwheel 12. For example, the separate part is pressed into the upper housing part 132 or the gearwheel 12 or is inserted into the injection mold by injection molding before the upper housing part 132 or the gearwheel 12 is produced.

Claims

Steering device for a motor vehicle, having - a contact unit (2) which is designed to produce an electrical connection between at least one component arranged on a steering handle of the steering device and a component located outside the steering device, wherein - the contact unit (2) has a housing (22) in which an electrical conductor element in the form of a winding tape (24) is located; a steering angle sensor (1) for determining a steering angle of the steering handle, comprising: at least one angle sensor (1) comprising at least one first transmission element (12) configured to cooperate with a second transmission element (21) following a rotation of the steering handle of the motor vehicle, wherein the second transmission element (21) is at least partially arranged in the housing (22) of the contact unit (2), characterized in that the angle sensor (1) comprises a multiturn sensor device (11) cooperating with the first transmission element (12), wherein the second transmission element (21) at least partially surrounds the winding tape (24).Steering device according to Claim 1, characterized in that the multiturn sensor device (11) is a magnetic multiturn sensor device.Steering device according to Claim 1 or 2, characterized in that the multiturn sensor device (11) comprises a magnetizable and / or conductive structure and at least one magnetic element (111), wherein the magnetizable and / or conductive structure and the magnetic element (111) are rotatable relative to one another.Steering device according to Claim 3, characterized in that the multiturn sensor device (11) is designed such that the magnetizable and / or conductive structure and / or the magnetic element (111) can be arranged - viewed in a direction perpendicular to a steering axis of the motor vehicle about which the steering handle is rotatable - at least partially next to a receptacle (23) for the electrical conductor element (24) formed by the housing (22).Steering device according to Claim 3 or 4, characterized in that the magnetic element (111) is designed in the form of a disc.Steering device according to Claims 3 to 5, characterized in that the magnetic element (111) is a permanent magnet.Steering device according to one of Claims 3 to 6, characterized in that the magnetic element (111) is connected to the first transmission element (12) in a rotationally fixed manner.Steering device according to one of Claims 3 to 7, characterized in that the magnetic element (111) is fastened to a housing which is connected to the first transmission element (12) in a rotationally fixed manner.Steering device according to one of Claims 3 to 8, characterized in that the magnetizable and / or conductive structure is arranged on a carrier (114) which does not follow a rotation of the first transmission element (12).Steering device according to one of the preceding claims, characterized in that the first transmission element (12) is a gearwheel or a gearwheel segment.Steering device according to one of the preceding claims, characterized in that the second gear element (21) at least partially revolves around a steering axis about which the steering handle is rotatable.Steering device according to one of the preceding claims, characterized in that the housing (22) forms a structure which centres the first transmission element (12).Steering device according to Claim 12, characterized in that the structure is designed in the form of a pin or a depression.

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