Steering system and electric vehicle

Abstract

The invention provides a steering system and an electric vehicle, and is applied to the technical field of electric vehicles. The steering system comprises a steering motor, a transmission mechanism, a lead screw, a steering controller and an angle sensor, a motor shaft of the steering motor is in transmission connection with the transmission mechanism, the steering motor is used for driving the lead screw to drive wheels of the electric vehicle to steer after the rotating speed is reduced through the transmission mechanism, and the transmission mechanism comprises a plurality of gears. The multiple gears comprise an input gear and an output gear, the input gear is in transmission connection with the motor shaft, the lead screw is sleeved with the output gear, the output gear is in transmission connection with the lead screw, and the angle sensor is used for detecting the rotation angle of the output gear; an angle signal from the angle sensor is received, and the rotating speed or torque output by the steering motor is controlled according to the rotating angle, indicated by the angle signal, of the output gear. Therefore, the control precision of the steering system is improved.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicles, and in particular to a steering system and an electric vehicle. Background Art

[0002] During the steering process of an electric vehicle, the steering motor drives the lead screw to steer the wheels, so accurately capturing the lead screw's axial displacement is crucial. However, the commonly used linear position sensor (LPS) has a fixed range and is unable to support the need to detect larger lead screw displacements. Furthermore, its detection error increases with displacement, making it difficult for the steering system to accurately control the wheel steering based on the lead screw's axial displacement. Summary of the Invention

[0003] An embodiment of the present application provides a steering system and an electric vehicle. During the process of the steering system driving the wheels of the electric vehicle to steer, the control accuracy of the steering system is improved by controlling the output of the steering motor based on the angle signal received from the angle sensor included in the steering system, thereby achieving precise control of the wheel steering.

[0004] In the first aspect, an embodiment of the present application provides a steering system, which includes a steering motor, a transmission mechanism, a screw, a steering controller and an angle sensor. The motor shaft of the steering motor is connected to the transmission mechanism. The steering motor is used to drive the screw to steer the wheels of the electric vehicle after reducing the speed through the transmission mechanism. The transmission mechanism includes multiple gears, and the multiple gears include an input gear connected to the motor shaft and an output gear sleeved on the screw and connected to the screw. The angle sensor is used to detect the rotation angle of the output gear.

[0005] The steering controller is used to receive the angle signal from the angle sensor and control the speed or torque output by the steering motor according to the rotation angle of the output gear indicated by the angle signal when the steering system drives the wheels of the electric vehicle to turn.

[0006] In this embodiment, in the process of the steering system driving the wheels of the electric vehicle to steer, the driving force that drives the vehicle to rotate is directly transmitted to the screw through the output gear. The angle of the output gear will not be affected by abnormalities of other components in the transmission mechanism (such as tooth jumping, slipping, tearing, etc. of the synchronous belt). The angle sensor is used to detect the rotation angle of the output gear, and the angle sensor is not limited by the range and can meet the detection needs of various ranges. The steering control receives the angle signal from the angle sensor and controls the speed or torque output by the steering motor according to the rotation angle of the output gear indicated by the angle signal. Compared with controlling the torque output by the steering motor according to the axial displacement of the screw indicated by the displacement signal from the linear displacement sensor, the control accuracy of the steering system is improved, and precise control of wheel steering is achieved.

[0007] In an embodiment of the first aspect, the angle sensor is a magnetic field sensor, which includes a magnet and a detection chip. The magnet rotates as the output gear rotates, and the detection chip determines the rotation angle of the output gear through the rotation angle of the magnet.

[0008] In this embodiment, the angle sensor is a magnetic field sensor, which includes a magnet and a detection chip. When the magnet rotates with the output gear, the detection chip determines the rotation angle of the output gear by detecting the rotation angle of the magnet, thereby detecting the rotation angle of the output gear.

[0009] In an embodiment of the first aspect, the steering system further includes a sensor mounting gear, the sensor mounting gear is meshed with the output gear and rotates with the rotation of the output gear, and the magnet is mounted on the sensor mounting gear.

[0010] In this embodiment, the steering system also includes a sensor-mounting gear that rotates with the output gear. A magnet is mounted on the sensor-mounting gear. The rotation angle of the magnet detected by the detection chip represents the rotation angle of the sensor-mounting gear. The sensor-mounting gear meshes with the output gear, making it easy to determine the rotation angle of the output gear based on the rotation angle of the sensor-mounting gear. Furthermore, the angle sensor in this embodiment of the application is simpler to install and smaller in size than a linear displacement sensor.

[0011] In one embodiment of the first aspect, the radius of the sensor mounting gear is smaller than the output gear and the number of teeth of the sensor mounting gear is smaller than the number of teeth of the output gear.

[0012] In this embodiment, by setting the radius of the sensor mounting gear to be smaller than the output gear and the number of teeth of the sensor mounting gear to be smaller than the number of teeth of the output gear, the volume of the sensor mounting gear is limited to be smaller than the output gear, so as to reduce the volume of the angle sensor, so that the installation of the angle sensor in the steering system does not require the expansion of the volume of the existing product.

[0013] In an embodiment of the first aspect, the sensor mounting gear and gears other than the output gear are spaced apart from each other.

[0014] In this embodiment, by setting the sensor mounting gear and other gears except the output gear at a distance, the rotation of the sensor mounting gear is only related to the rotation of the output gear and is not affected by abnormalities of other gears or other components, thereby further improving the detection accuracy of the rotation angle of the output gear.

[0015] In an embodiment of the first aspect, the magnet is an annular magnet, which is sleeved on the lead screw and fixed to an end surface of the output gear, and the magnet rotates as the output gear rotates.

[0016] In this embodiment, the magnet is an annular magnet. By setting the magnet to be sleeved on the screw and fixed to one end face of the output gear, the magnet rotates as the output gear rotates, thereby obtaining the rotation angle of the output gear by detecting the rotation angle of the magnet.

[0017] In an embodiment of the first aspect, the steering system further comprises a sensor mounting shaft, the sensor mounting shaft being fixed to an end face of the output gear along the axial direction of the output gear, the sensor mounting shaft and the output gear rotating coaxially, and the magnet being fixedly mounted on the sensor mounting shaft.

[0018] In this embodiment, the angle sensor also includes a sensor mounting shaft, which is fixed to an end face of the output gear along the axial direction of the output gear. The sensor mounting shaft and the output gear rotate coaxially, and the magnet is fixedly mounted on the sensor mounting shaft so that the magnet rotates as the output gear rotates, thereby obtaining the rotation angle of the output gear by detecting the rotation angle of the magnet.

[0019] In an embodiment of the first aspect, a diameter of the sensor mounting shaft is smaller than a diameter of the output gear, and the sensor mounting shaft and the output gear are cocentrically arranged.

[0020] In this embodiment, by setting the diameter of the sensor mounting shaft smaller than that of the output gear, the size of the sensor mounting shaft is limited. This allows the angle sensor to be installed in the steering system without increasing the size of existing products. Furthermore, the concentric arrangement of the sensor mounting shaft and the output gear improves the structural stability of the angle sensor.

[0021] In an embodiment of the first aspect, the angle sensor is a resolver sensor, and the angle sensor includes an annular stator, which is sleeved on the lead screw.

[0022] In this embodiment, the angle sensor is a resolver sensor, which includes an annular stator. The annular stator is sleeved on the lead screw. The output gear or the lead screw is used as the rotor of the resolver sensor. The rotation angle of the output gear is detected by detecting the rotation angle of the rotor.

[0023] In an embodiment of the first aspect, the steering system includes a housing, the transmission mechanism and the angle sensor are accommodated in the housing, and the angle sensor is connected to the steering controller via a connecting line provided in the housing.

[0024] In this embodiment, a housing is provided to house the transmission mechanism and angle sensor, protecting them from external damage and malfunction. Furthermore, the angle sensor is connected to the steering controller via a connecting wire within the housing. Compared to linear displacement sensors, the angle sensor provided in this application does not require external terminals on the housing to connect to the steering controller, reducing costs.

[0025] In an embodiment of the first aspect, the angle sensor is used to output multiple angle signals with different frequencies to the steering controller; the steering controller is specifically used to: calculate the rotation angle of the output gear based on the received multiple angle signals with different frequencies, and control the speed or torque output by the steering motor based on the rotation angle of the output gear.

[0026] In this embodiment, the angle sensor is used to output multiple angle signals of different frequencies to the steering controller. The steering controller calculates the rotation angle of the output gear based on the received multiple angle signals of different frequencies, and controls the speed or torque output by the steering motor based on the rotation angle of the output gear, thereby expanding the measuring range and detection accuracy of the angle sensor, and multiple angle signals realize redundant backup.

[0027] In a second aspect, an embodiment of the present application provides an electric vehicle, which includes a steering system; the steering system includes a steering motor, a transmission mechanism, a lead screw, a steering controller and an angle sensor, the motor shaft of the steering motor is connected to the transmission mechanism, the steering motor is used to drive the lead screw to drive the wheels of the electric vehicle to steer after reducing the speed through the transmission mechanism, the transmission mechanism includes a plurality of gears, the plurality of gears include an input gear connected to the motor shaft and an output gear sleeved on the lead screw and connected to the lead screw, and the angle sensor is used to detect the rotation angle of the output gear.

[0028] The steering controller is used to receive the angle signal from the angle sensor and control the speed or torque output by the steering motor according to the rotation angle of the output gear indicated by the angle signal when the steering system drives the wheels of the electric vehicle to turn.

[0029] In an embodiment of the second aspect, the angle sensor is a magnetic field sensor, which includes a magnet and a detection chip. The magnet rotates as the output gear rotates, and the detection chip determines the rotation angle of the output gear through the rotation angle of the magnet.

[0030] In an embodiment of the second aspect, the steering system further includes a sensor mounting gear, the sensor mounting gear is meshed with the output gear and rotates with the rotation of the output gear, and the magnet is mounted on the sensor mounting gear.

[0031] In an embodiment of the second aspect, the angle sensor is a resolver sensor, and the angle sensor includes an annular stator, which is sleeved on the lead screw.

[0032] For the supplementary and technical effects of the solution provided in the second aspect above, please refer to the corresponding description of the first aspect and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 shows a schematic diagram of a steering system;

[0034] Figure 2 shows a schematic diagram of another steering system;

[0035] Figure 3 A schematic diagram of an electric vehicle provided in an embodiment of the present application is shown;

[0036] Figure 4 A schematic diagram of an electric vehicle architecture provided by an embodiment of the present application is shown;

[0037] Figure 5 A schematic diagram of a steering system provided in an embodiment of the present application is shown;

[0038] Figure 6 A schematic diagram of a transmission mechanism provided in an embodiment of the present application is shown;

[0039] Figure 7 A schematic diagram of another transmission mechanism provided in an embodiment of the present application is shown;

[0040] Figure 8 A schematic diagram of an angle sensor provided in an embodiment of the present application is shown;

[0041] Figure 9 A schematic diagram of another angle sensor provided in an embodiment of the present application is shown;

[0042] Figure 10 A schematic structural diagram of an angle sensor provided in an embodiment of the present application is shown;

[0043] Figure 11A schematic structural diagram of another angle sensor provided in an embodiment of the present application is shown;

[0044] Figure 12 A schematic structural diagram of another angle sensor provided in an embodiment of the present application is shown;

[0045] Figure 13 A schematic diagram of another angle sensor provided in an embodiment of the present application is shown;

[0046] Figure 14 A schematic structural diagram of another angle sensor provided in an embodiment of the present application is shown;

[0047] Figure 15 A schematic structural diagram of yet another angle sensor provided in an embodiment of the present application is shown;

[0048] Figure 16 A structural schematic diagram of a steering system provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0049] The technical solutions in the embodiments of the present application will be described below with reference to the accompanying drawings.

[0050] In the embodiments of this application, prefixes such as "first" and "second" are used only to distinguish different description objects and have no limiting effect on the position, order, priority, quantity, or content of the described objects. The use of prefixes such as ordinal numbers in the embodiments of this application to distinguish description objects does not constitute a limitation on the described objects. For a statement of the described objects, please refer to the description in the context of the claims or embodiments, and the use of such prefixes should not constitute an unnecessary limitation.

[0051] In the steering system, when the steering motor rotates to drive the axial displacement of the tie rod and thus drive the wheel to turn, see Figure 1 A linear position sensor 10 (LPS) is usually used to detect the displacement of the tie rod 11. However, the LSP has a fixed range and is difficult to support the demand for detecting larger displacements. Moreover, its detection error increases with the increase of displacement.

[0052] See also Figure 2 , Figure 2 FIG1 shows a schematic diagram of another steering system, in which a sensor 13 is provided for detecting the rotation speed of the steering motor 12, and then the displacement of the tie rod 11 is calculated by the detected rotation speed. Figure 2In the steering system shown, the entire transmission mechanism 14 is required to transmit the driving force between the steering motor 12 and the tie rod 11. If an abnormality occurs in the transmission mechanism 14, the difference between the actual displacement of the tie rod and the calculated displacement of the tie rod will increase, and the accuracy of obtaining the displacement of the tie rod will be low, thereby affecting the control accuracy of the wheel steering.

[0053] In view of this, an embodiment of the present application provides a steering system and an electric vehicle. In the process of the steering system driving the wheels of the electric vehicle to steer, the control accuracy of the steering system is improved by controlling the output of the steering motor based on the angle signal received from the angle sensor included in the steering system, thereby achieving precise control of the wheel steering.

[0054] See also Figure 3 , Figure 3 A schematic diagram of an electric vehicle is shown. Figure 3 As shown, the electric vehicle 100 includes a rear-wheel steering system 110 , a front-wheel steering system 120 , a vehicle controller 130 and a power battery 140 .

[0055] The rear-wheel steering system 110 is used to drive the rear wheels of the electric vehicle 100. The front-wheel steering system 110 is used to drive the front wheels of the electric vehicle 100. The vehicle controller 130 is used to control the rear-wheel steering system 110 and the front-wheel steering system 120 of the electric vehicle 100. The power battery 140 is used to provide power to the rear-wheel steering system 110 and the front-wheel steering system 120.

[0056] The electric vehicle 100 in the embodiment of the present application can specifically be any one of different types of vehicles such as a car, a truck, a passenger bus, etc., and can also be a transportation device for carrying people or goods such as a tricycle, a two-wheeled vehicle, a train, or other types of transportation vehicles driven by power batteries. The embodiment of the present application is not limited to this.

[0057] The power battery 140 in the embodiment of the present application can be a lithium-ion battery, a lithium metal battery, a lead-acid battery, a nickel-cadmium battery, a nickel-hydrogen battery, a lithium-sulfur battery, a lithium-air battery or a sodium-ion battery, etc., and the present application does not limit this.

[0058] See also Figure 4 , Figure 4 A schematic diagram of an electric vehicle architecture is shown, where the electric vehicle 100 further includes rear wheels 150 and front wheels 160 .

[0059] Figure 4 (a) in FIG. 1 shows a schematic diagram of a centralized steering system, such as Figure 4 As shown in (a) of FIG. 8 , the rear-wheel steering system 110 includes a steering motor 111 , a steering controller 112 and a steering gear 113 .

[0060] The steering motor 111 is used to provide driving force for steering the rear wheels of the electric vehicle 100. The steering controller 112 is used to control the output torque of the steering motor 111. The steering gear 113 is used to drive the rear wheels 150 of the electric vehicle to steer according to the output torque of the steering motor 111.

[0061] During the steering process of the electric vehicle 100, the steering controller 112 receives a steering angle signal from the vehicle controller 130 and receives a steering angle signal from the power battery 140 (eg, Figure 3 The electric energy (as shown) is used to control the steering motor 111 to output torque according to the steering angle indicated by the steering angle signal.

[0062] Among them, the torque output by the steering motor 111 includes forward torque and reverse torque. When the steering motor 111 outputs forward torque and outputs reverse torque, the steering direction of the rear wheel 150 is opposite. For example, when the steering motor 111 outputs forward torque, the rear wheel 150 of the electric vehicle 100 turns left, and when it outputs reverse torque, the rear wheel 150 of the electric vehicle 100 turns right.

[0063] like Figure 4 As shown in (a) in FIG. 8 , the front wheel steering system 120 includes a steering motor 121 , a steering controller 122 and a steering gear 123 .

[0064] The steering motor 121 is used to provide driving force for steering the front wheels 160 of the electric vehicle 100. The steering controller 122 is used to control the output torque of the steering motor 121. The steering gear 123 is used to drive the front wheels of the electric vehicle to steer according to the output torque of the steering motor 121.

[0065] During the steering process of the electric vehicle 100, the steering controller 122 receives a steering angle signal from the vehicle controller 130 and receives a steering angle signal from the power battery 140 (eg, Figure 3 The steering motor 121 outputs torque according to the steering angle indicated by the steering angle signal.

[0066] Similarly, the torque output by the steering motor 111 and the steering motor 121 includes a positive torque and a negative torque. When the steering motor 121 outputs the positive torque and the negative torque, the steering directions of the front wheels of the electric vehicle 100 are opposite.

[0067] Figure 4 (b) in FIG. 1 shows a schematic diagram of a distributed steering system, such as Figure 4 As shown in (b) in the figure, the rear-wheel steering system 110 includes a steering motor 114 for the left rear wheel, a steering controller 115 for the left rear wheel, a steering gear 116 for the left rear wheel, a steering motor 117 for the right rear wheel, a steering controller 118 for the right rear wheel and a steering gear 119 for the right rear wheel.

[0068] The front wheel steering system 120 includes a left front wheel steering motor 124, a left front wheel steering controller 125 and a left front wheel steering gear 126, and a right front wheel steering motor 127, a right front wheel steering controller 128 and a right front wheel steering gear 129.

[0069] See also Figure 5 , Figure 5 A schematic diagram of a steering system is shown. Figure 5 by Figure 4 Taking the centralized steering system shown in (a) as an example, Figure 5 The steering system 20 shown may be a front wheel steering system 120 or a rear wheel steering system 110 .

[0070] like Figure 5 As shown, the steering system 20 includes a steering motor 21, a steering controller 22 and a steering gear 23. The steering motor 21 is in transmission connection with the steering controller 22 and the steering gear 23. The steering motor 21 is used to drive the wheels of the electric vehicle to steer through the steering gear 23.

[0071] The steering motor 21 and the steering controller 22 may be integrated into one body, and the steering gear 23 is connected to at least one wheel of the electric vehicle.

[0072] The steering gear 23 includes a transmission mechanism 231 , a lead screw 232 and a tie rod 233 .

[0073] The motor shaft of the steering motor 21 is connected to the transmission mechanism 231. The steering motor 21 is used to drive the screw 232 to drive the wheels of the electric vehicle to steer after reducing the speed through the transmission mechanism 231. The screw 232 can be a trapezoidal screw, a planetary roller screw, a ball screw, etc.

[0074] The two ends of the lead screw 232 are respectively hinged to a tie rod 233 , and the other ends of the two tie rods 233 are connected to the wheels of the electric vehicle through steering knuckles.

[0075] In the process of the steering system driving the wheels of the electric vehicle to steer, after the steering controller 22 receives the steering angle indicated by the steering angle signal, it controls the steering motor 21 to output torque, which is converted into a torque suitable for steering through the transmission mechanism 231. Thereafter, the converted torque is transmitted to the screw 232, which converts the rotational motion of the steering motor 21 into a linear motion axial displacement to drive the axial displacement of the tie rod 233. Finally, the wheel steering is driven by the tie rod 233.

[0076] See also Figure 6 , Figure 6 A schematic diagram of a transmission mechanism is shown.

[0077] The transmission mechanism 231 includes a plurality of gears, including an input gear 2311 transmission-connected to the motor shaft 211 and an output gear 2312 sleeved on the lead screw 232 and transmission-connected to the lead screw 232 .

[0078] like Figure 6 As shown, the input gear 2311 is sleeved on the motor shaft 211 and rotates with the rotation of the motor shaft 211. The input gear 2311 and the output gear 2312 are connected by a synchronous belt 2313. The output gear 2312 is sleeved on the nut of the screw 232, and the inner surface of the output gear 2312 is tightly fitted with the screw 232.

[0079] When the motor shaft 211 drives the input gear 2311 to rotate, the output gear 2312 rotates with the rotation of the input gear 2311 and drives the nut of the lead screw 232 to rotate.

[0080] It is understandable that Figure 6 The diagram merely illustrates a connection method between the input gear 2311 and the motor shaft 211 , a connection method between the output gear 2312 and the lead screw 232 , and a transmission method between the input gear 2311 and the output gear 2312 , without limiting the specific connection method and transmission method.

[0081] In one embodiment, the input gear 2311 and the output gear 2312 may be connected via a coupling, may be driven by a rack, a chain, other gears, etc., or may be directly meshed.

[0082] In another embodiment, the input gear 2311 and the output gear 2312, the input gear 2311 and the motor shaft 211, and the output gear 2312 and the lead screw 232 can all be configured to form a planetary gear set to achieve transmission. In this case, the outer or inner side of the motor shaft 211 and the outer side of the lead screw 232 have teeth that can mesh with the gears.

[0083] See also Figure 7 , Figure 7 A schematic diagram of another transmission mechanism is shown. Figure 6 A tensioner 2314 is added to the structure of the transmission mechanism 231 shown. The outer peripheral surface of the tensioner 2314 contacts the outer surface of the synchronous belt 2313 and squeezes the synchronous belt 2313 to keep the synchronous belt 2313 in a taut state, thereby increasing the tension between the synchronous belt 2313 and the input gear 2311 and the output gear 2312, preventing the synchronous belt 2313 from slipping and reducing the risk of the synchronous belt 2313.

[0084] The architecture of the embodiment of the present application is described above, and the embodiment of the present application proposes a steering system.

[0085] In one embodiment, the steering system may be a front wheel steering system.

[0086] In another embodiment, the steering system may be a rear wheel steering system.

[0087] The steering system further includes an angle sensor 24, which is used to detect the rotation angle of the output gear 2312. Figure 8 , Figure 8 A schematic diagram of an angle sensor is shown.

[0088] The steering controller 22 is used to receive an angle signal from the angle sensor and control the speed or torque output by the steering motor 21 according to the rotation angle of the output gear 2312 indicated by the angle signal when the steering system drives the wheels of the electric vehicle to turn.

[0089] based on Figure 6 and Figure 7 From the analysis of the transmission mechanism 231 shown, it can be seen that: the steering motor outputs driving force, the input gear and the output gear transmit the driving force to the screw, the screw converts the rotational motion into linear motion and transmits it to the tie rod, so that the tie rod is displaced in the axial direction to drive the wheel to steer.

[0090] That is to say, the driving force exerted on the tie rod to drive the steering of the wheel is directly transmitted to the screw by the output gear. The rotation angle of the output gear is the same as the rotation angle of the screw. According to the rotation angle of the output gear, the axial displacement of the screw or the steering angle of the wheel of the electric vehicle can be easily obtained. The axial displacement of the screw is the displacement of the tie rod.

[0091] Specifically, after obtaining the rotation angle of the output gear, the axial displacement of the screw is calculated according to the rotation angle of the output gear, including: calculating the axial displacement of the screw according to the lead of the screw and the angle of the output gear; or calculating the axial displacement of the screw according to the angle of the output gear and the pitch radius of the output gear.

[0092] When the axial displacement of the screw is large, the calculated axial displacement of the screw is more accurate than the displacement of the tie rod detected by the linear displacement sensor. Subsequently, the speed or torque output by the steering motor can be precisely controlled according to the rotation angle control of the output gear, thereby precisely controlling the steering of the wheel.

[0093] In this embodiment, in the process of the steering system driving the wheels of the electric vehicle to steer, the driving force that drives the vehicle to rotate is directly transmitted to the screw through the output gear. The angle of the output gear will not be affected by abnormalities of other components in the transmission mechanism (such as tooth jumping, slipping, tearing, etc. of the synchronous belt). The angle sensor is used to detect the rotation angle of the output gear, and the angle sensor is not limited by the range and can meet the detection needs of various ranges. The steering control receives the angle signal from the angle sensor and controls the speed or torque output by the steering motor according to the rotation angle of the output gear indicated by the angle signal. Compared with controlling the torque output by the steering motor according to the displacement of the transverse tie rod indicated by the displacement signal from the linear displacement sensor, the control accuracy of the steering system is improved, and precise control of wheel steering is achieved.

[0094] See also Figure 9 , Figure 9 A schematic diagram of another angle sensor is shown.

[0095] like Figure 9 As shown, in one embodiment, the angle sensor 24 is a magnetic field sensor, which includes a magnet 241 and a detection chip 242. The magnet 241 rotates with the rotation of the output gear 2312, and the detection chip 242 determines the rotation angle of the output gear 2312 through the rotation angle of the magnet 241.

[0096] It can be understood that the magnet rotates along with the rotation of the output gear, and the rotation angle of the output gear can be easily determined based on the rotation angle of the magnet.

[0097] The magnet 241 may be a magnet including an N pole and an S pole.

[0098] The detection chip 242 can be a tunneling magnetoresistance chip (TMR), anisotropic magnetoresistance chip (AMR), giant magnetoresistance chip (GMR), Hall chip (HALL), etc. The detection chip 242 does not contact the magnet 241 and senses the rotation angle of the magnet.

[0099] As the magnet rotates with the output gear, the direction of the magnetic field changes. The resistance of TMR / AMR / GMR changes with the change in the direction of the magnetic field. The rotation angle of the magnet can be calculated through the resistance of TMR / AMR / GMR. Among them, TMR has higher detection accuracy than AMR and GMR.

[0100] As the magnet rotates with the output gear, the direction or strength of the magnetic field will change. The voltage of the Hall will change with the change of the direction or strength of the magnetic field. The rotation angle of the magnet can be calculated through the voltage of the Hall.

[0101] In this embodiment, the angle sensor is a magnetic field sensor, which includes a magnet and a detection chip. When the magnet rotates with the output gear, the detection chip determines the rotation angle of the output gear by detecting the rotation angle of the magnet, thereby detecting the rotation angle of the output gear.

[0102] See also Figure 10 , Figure 10 A structural schematic diagram of an angle sensor is shown.

[0103] like Figure 10 As shown, in one embodiment, the steering system 20 further includes a sensor mounting gear 25 , which is meshed with the output gear 2312 and rotates along with the rotation of the output gear 2312 , and the magnet 241 is mounted on the sensor mounting gear 25 .

[0104] In the embodiments of the present application, there is no limitation on the specific installation method of the magnet on the sensor mounting gear.

[0105] In one embodiment, Figure 10 As shown in (b), the magnet is coaxially connected to the sensor mounting gear through a connecting shaft.

[0106] In another embodiment, the magnet may be connected to the sensor mounting gear via a connecting flange, or one end face of the magnet may be tightly connected to one end face of the sensor mounting gear.

[0107] The rotation angle of the magnet detected by the detection chip is the rotation angle of the sensor mounting gear.

[0108] When the steering motor drives the output gear to rotate, the sensor mounting gear rotates with the output gear. After obtaining the rotation angle of the sensor mounting gear, the rotation angle of the output gear can be calculated based on the gear ratio of the sensor mounting gear and the output gear.

[0109] In this embodiment, the steering system also includes a sensor-mounting gear that rotates with the output gear. A magnet is mounted on the sensor-mounting gear. The rotation angle of the magnet detected by the detection chip represents the rotation angle of the sensor-mounting gear. The sensor-mounting gear meshes with the output gear, making it easy to determine the rotation angle of the output gear based on the rotation angle of the sensor-mounting gear. Furthermore, the angle sensor in this embodiment of the application is simpler to install and smaller in size than a linear displacement sensor.

[0110] In one embodiment, there may be multiple sensor mounting gears, and the position of the angle sensor in the steering system may be adjusted through the meshing relationship between the multiple sensor mounting gears.

[0111] See also Figure 10 In (a), in one embodiment, the radius of the sensor mounting gear 25 is smaller than that of the output gear 2312 and the number of teeth of the sensor mounting gear 25 is smaller than that of the output gear 2312 .

[0112] That is, the volume of the sensor mounting gear is smaller than that of the output gear, and the space required to install the sensor mounting gear is smaller.

[0113] In this embodiment, by setting the radius of the sensor mounting gear to be smaller than the output gear and the number of teeth of the sensor mounting gear to be smaller than the number of teeth of the output gear, the volume of the sensor mounting gear is limited to be smaller than the output gear, so as to reduce the volume of the angle sensor, so that the installation of the angle sensor in the steering system does not require the expansion of the volume of the existing product.

[0114] In one embodiment, see Figure 10 In (a), the sensor mounting gear 25 and the other gears except the output gear 2312 are spaced apart.

[0115] That is, the sensor mounting gear does not contact the input gear and the tensioner.

[0116] In this embodiment, by setting the sensor mounting gear and other gears except the output gear at a distance, the rotation of the sensor mounting gear is only related to the rotation of the output gear and is not affected by abnormalities of other gears or other components, thereby further improving the detection accuracy of the rotation angle of the output gear.

[0117] See also Figure 11 , Figure 11 A schematic structural diagram of another angle sensor is shown.

[0118] like Figure 11 As shown, in one embodiment, the magnet 241 is an annular magnet. The magnet 241 is sleeved on the lead screw 232 and fixed to one end surface of the output gear 2312 . The magnet 241 rotates as the output gear 2312 rotates.

[0119] The inner wall of the magnet does not contact the lead screw.

[0120] The magnet is fixed to one end face of the output gear so that the rotation angle of the magnet is the same as the rotation angle of the output gear.

[0121] In one embodiment, the annular magnet may be composed of a single pair (one N pole and one S pole) or multiple pairs of magnetic poles (multiple N poles and multiple S poles), with the N poles and S poles being arranged in a cross pattern.

[0122] like Figure 11 As shown, the angle sensor including a single pair of magnetic poles is as shown in FIG. Figure 11 As shown in (a) of FIG. , the angle sensor includes multiple pairs of magnetic poles. Figure 11 As shown in (b) in FIG. 1 , the detection accuracy of the angle sensor including multiple pairs of magnetic poles is higher than that of the angle sensor including a single pair of magnetic poles.

[0123] In this embodiment, the magnet is an annular magnet. By setting the magnet to be sleeved on the screw and fixed to one end face of the output gear, the magnet rotates as the output gear rotates, thereby obtaining the rotation angle of the output gear by detecting the rotation angle of the magnet.

[0124] See also Figure 12 , Figure 12 A schematic diagram of yet another angle sensor is shown.

[0125] like Figure 12 As shown, in one embodiment, the steering system 20 also includes a sensor mounting shaft 26, which is fixed to an end face of the output gear 2312 along the axial direction of the output gear 2312, the sensor mounting shaft 26 and the output gear 2312 rotate coaxially, and the magnet 241 is fixedly mounted on the sensor mounting shaft 26.

[0126] In one embodiment, the sensor mounting shaft may be as follows Figure 12 As shown, the sensor mounting shaft is a hollow cylinder, and the inner wall of the sensor mounting shaft does not contact the lead screw or the tie rod.

[0127] In the distributed steering system, the angle sensors 24 corresponding to the coaxial wheels (such as the left rear wheel and the right rear wheel) are symmetrically distributed, such as Figure 13 As shown, Figure 13 A schematic diagram of yet another angle sensor is shown.

[0128] In this embodiment, the angle sensor also includes a sensor mounting shaft, which is fixed to an end face of the output gear along the axial direction of the output gear. The sensor mounting shaft and the output gear rotate coaxially, and the magnet is fixedly mounted on the sensor mounting shaft so that the magnet rotates as the output gear rotates, thereby obtaining the rotation angle of the output gear by detecting the rotation angle of the magnet.

[0129] Continue to see Figure 12 and Figure 13In one embodiment, the diameter of the sensor mounting shaft 26 is smaller than the diameter of the output gear 2312 , and the sensor mounting shaft 26 and the output gear 2312 are cocentrically arranged.

[0130] The sensor mounting shaft and the output gear are arranged concentrically, which means that the center of the cross section of the sensor mounting shaft is the same as the center of the output gear.

[0131] In this embodiment, by setting the diameter of the sensor mounting shaft smaller than that of the output gear, the size of the sensor mounting shaft is limited, allowing the angle sensor to be installed in the steering system without increasing the volume of existing products. Furthermore, by arranging the sensor mounting shaft and the output gear concentrically, the structural stability of the angle sensor is improved.

[0132] In another embodiment, the sensor mounting shaft 26 may be a sensor mounting bracket 27, such as Figure 14 As shown, Figure 14 Schematic diagram of another angle sensor is shown, in which the support frame 27 is composed of multiple columns, and the multiple columns do not contact the transverse rod.

[0133] The sensor mounting shaft 26 and the sensor mounting bracket 27 shown above are merely exemplary, and their specific shapes are not limited in the embodiment of the present application.

[0134] See also Figure 15 , Figure 15 A structural schematic diagram of yet another angle sensor is shown.

[0135] like Figure 15 As shown, in one embodiment, the angle sensor 24 is a resolver sensor, and the angle sensor 24 includes an annular stator 243 , which is sleeved on the lead screw 232 .

[0136] In one embodiment, the annular stator 243 is parallel to the output gear 2312 and the distance between the annular stator 243 and the output gear 2312 does not rotate with the rotation of the output gear.

[0137] In this embodiment of the present application, the output gear 2312 or the lead screw 232 serves as the rotor of the resolver sensor. As the output gear rotates, the resolver sensor decodes the rotor's rotation angle, which is the output gear's rotation angle, by detecting the electromagnetic coupling signal between the annular stator and the rotor.

[0138] In this embodiment, the angle sensor is a resolver sensor, which includes an annular stator. The annular stator is sleeved on the lead screw. The output gear or the lead screw is used as the rotor of the resolver sensor. The rotation angle of the output gear is detected by detecting the rotation angle of the rotor.

[0139] See also Figure 16 , Figure 16A structural schematic diagram of a steering system is shown.

[0140] like Figure 16 As shown, in one embodiment, the steering system 20 includes a housing 28 , a transmission mechanism 231 and an angle sensor 24 are accommodated in the housing 28 , and the angle sensor 24 is connected to the steering controller 22 via a connecting line 29 provided in the housing 28 .

[0141] The connecting line 29 can be fixed on the inner wall of the housing 28. The angle signal is a hard-wired signal, and the stability of the signal transmission is stronger.

[0142] In this embodiment, a housing is provided to house the transmission mechanism and angle sensor, protecting them from external damage and malfunction. Furthermore, the angle sensor is connected to the steering controller via a connecting wire within the housing. Compared to linear displacement sensors, the angle sensor provided in this application does not require external terminals on the housing to connect to the steering controller, reducing costs.

[0143] In one embodiment, the angle sensor 24 is wirelessly connected to the steering controller 22 .

[0144] The wireless connection method may be Bluetooth, Wi-Fi (e.g., Quectel MCU Wi-Fi FC41D), etc. During wireless communication between the angle sensor and the steering controller, there is no restriction on the specific power supply method of the direction detection chip, such as battery power, wireless charging, etc.

[0145] In this embodiment, the angle sensor is wirelessly connected to the steering controller, and there is no need to consider the wiring between the angle sensor and the steering controller, thereby reducing costs.

[0146] In one embodiment, the angle sensor 24 is connected to the steering controller 22 via a connection line 29 disposed in the housing 28 and is wirelessly connected to the steering controller 22 .

[0147] In this embodiment, the angle sensor and the steering controller are connected both via a connecting wire and wirelessly. The wired and wireless connection methods support high-speed and large-capacity transmission, and the wired and wireless connection methods realize redundant backup, thereby improving the reliability of signal transmission.

[0148] In one embodiment, the angle sensor 24 is used to output multiple angle signals of different frequencies to the steering controller 22; the steering controller 22 is specifically used to: calculate the rotation angle of the output gear 2312 based on the received multiple angle signals of different frequencies, and control the speed or torque output by the steering motor 21 according to the rotation angle of the output gear 2312.

[0149] The multiple angle signals may be detected by multiple detection chips included in the angle sensor.

[0150] In one embodiment, the steering controller uses a vernier algorithm to perform calculations based on a plurality of received angle signals with different frequencies, thereby obtaining a more accurate and larger range of axial displacement of the lead screw.

[0151] In another embodiment, the multiple angle signals may include a signal for recording the number of rotations of the magnet. The steering controller can calculate the axial displacement of the screw more accurately and in a larger range based on the number of rotations and angles of the magnet.

[0152] In this embodiment, the angle sensor is used to output multiple angle signals of different frequencies to the steering controller. The steering controller calculates the rotation angle of the output gear based on the received multiple angle signals of different frequencies, and controls the speed or torque output by the steering motor based on the rotation angle of the output gear, thereby expanding the measuring range and detection accuracy of the angle sensor, and multiple angle signals realize redundant backup.

[0153] In one embodiment, the angle sensor can also send an electrical signal (such as a voltage signal, a resistance signal, etc.) to the steering controller for calculating the rotation angle of the magnet. The steering controller solves the information indicated by the electrical signal to obtain the rotation angle of the magnet, and then calculates the axial displacement of the screw.

[0154] In one embodiment, the angle sensor proposed in the aforementioned embodiment can be used to detect the rotation angle of the input gear and control the output torque of the steering motor based on the rotation angle of the input gear. The specific arrangement of the angle sensor is similar to the arrangement of the angle sensor on the output gear in the aforementioned embodiment and will not be further described here.

[0155] In one embodiment, the angle sensor proposed in the aforementioned embodiment can also be used to detect the rotational angle of a gear other than the input and output gears in the transmission mechanism, and control the output torque of the steering motor based on the rotational angle of the gear. The specific arrangement of the angle sensor is similar to that of the output gear in the aforementioned embodiment and will not be further described here.

[0156] In one embodiment, the angle sensor proposed in the aforementioned embodiment can be used to detect the rotation angle of the motor shaft of the steering motor and control the output torque of the steering motor based on the rotation angle of the motor shaft. The specific arrangement of the angle sensor is similar to the arrangement of the angle sensor on the output gear in the aforementioned embodiment and will not be further described here.

[0157] Another embodiment of the present application provides an electric vehicle, which includes a steering system; the steering system includes a steering motor, a transmission mechanism, a screw, a steering controller and an angle sensor, the motor shaft of the steering motor is connected to the transmission mechanism, the steering motor is used to drive the screw to drive the wheels of the electric vehicle to steer after reducing the speed through the transmission mechanism, the transmission mechanism includes multiple gears, the multiple gears include an input gear connected to the motor shaft and an output gear sleeved on the screw and connected to the screw, and the angle sensor is used to detect the rotation angle of the output gear 2312.

[0158] The steering controller 22 is used to receive an angle signal from the angle sensor and control the speed or torque output by the steering motor 21 according to the rotation angle of the output gear 2312 indicated by the angle signal when the steering system drives the wheels of the electric vehicle to turn.

[0159] In one embodiment, the angle sensor 24 is a magnetic field sensor, which includes a magnet 241 and a detection chip 242 . The magnet 241 rotates with the rotation of the output gear 2312 , and the detection chip 242 determines the rotation angle of the output gear 2312 through the rotation angle of the magnet 241 .

[0160] In one embodiment, the steering system 20 further includes a sensor mounting gear 25 . The sensor mounting gear 25 is meshed with the output gear 2312 and rotates along with the rotation of the output gear 2312 . The magnet 241 is mounted on the sensor mounting gear 25 .

[0161] In one embodiment, the angle sensor 24 is a resolver sensor. The angle sensor 24 includes an annular stator 243 , which is sleeved on the lead screw 232 .

[0162] It can be understood that all relevant contents of each step involved in the above-mentioned steering system embodiment can be referred to the embodiment of the electric vehicle, and the embodiment of the present application will not be repeated here.

[0163] Finally, it should be noted that the above are only specific embodiments of this application, but the scope of protection of this application is not limited to them. Any changes or substitutions within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A steering system, characterized in that: The steering system includes a steering motor, a transmission mechanism, a lead screw, a steering controller, and an angle sensor. The motor shaft of the steering motor is in transmission connection with the transmission mechanism. The steering motor is used to drive the lead screw after reducing the speed through the transmission mechanism to drive the wheels of the electric vehicle to steer. The transmission mechanism includes a plurality of gears, each of which includes an input gear in transmission connection with the motor shaft and an output gear sleeved on the lead screw and in transmission connection with the lead screw. The angle sensor is used to detect the rotation angle of the output gear. The steering controller is used to: When the steering system drives the wheels of the electric vehicle to steer, the steering system receives an angle signal from the angle sensor and controls the speed or torque output by the steering motor according to the rotation angle of the output gear indicated by the angle signal.

2. The steering system according to claim 1, characterized in that The angle sensor is a magnetic field sensor, which includes a magnet and a detection chip. The magnet rotates as the output gear rotates, and the detection chip determines the rotation angle of the output gear according to the rotation angle of the magnet.

3. The steering system according to claim 2, characterized in that The steering system further includes a sensor mounting gear, which is meshed with the output gear and rotates along with the rotation of the output gear, and the magnet is mounted on the sensor mounting gear.

4. The steering system according to claim 2, characterized in that The radius of the sensor mounting gear is smaller than that of the output gear and the number of teeth of the sensor mounting gear is smaller than that of the output gear.

5. The steering system according to claim 2, characterized in that: The sensor mounting gear and other gears except the output gear are spaced apart from each other.

6. The steering system according to claim 2, characterized in that: The magnet is an annular magnet, which is sleeved on the lead screw and fixed to one end surface of the output gear. The magnet rotates as the output gear rotates.

7. The steering system according to claim 2, characterized in that The steering system further includes a sensor mounting shaft, which is fixed to an end face of the output gear along the axial direction of the output gear. The sensor mounting shaft and the output gear rotate coaxially, and the magnet is fixedly mounted on the sensor mounting shaft.

8. The steering system according to claim 2, characterized in that: The diameter of the sensor installation shaft is smaller than the diameter of the output gear, and the sensor installation shaft and the output gear are arranged concentrically.

9. The steering system according to claim 1, characterized in that The angle sensor is a resolver sensor, and the angle sensor includes an annular stator, which is sleeved on the lead screw.

10. The steering system according to claim 1, wherein: The steering system includes a housing, the transmission mechanism and the angle sensor are accommodated in the housing, and the angle sensor is connected to the steering controller via a connecting line provided in the housing.

11. The steering system according to any one of claims 1 to 10, characterized in that: The angle sensor is used to output a plurality of angle signals with different frequencies to the steering controller; the steering controller is specifically used to: The rotation angle of the output gear is calculated according to the received multiple angle signals with different frequencies, and the speed or torque output by the steering motor is controlled according to the rotation angle of the output gear.

12. An electric vehicle, characterized in that: The electric vehicle includes a steering system; the steering system includes a steering motor, a transmission mechanism, a lead screw, a steering controller, and an angle sensor. The motor shaft of the steering motor is in transmission connection with the transmission mechanism. The steering motor is used to drive the lead screw after reducing the speed through the transmission mechanism to drive the wheels of the electric vehicle to steer. The transmission mechanism includes a plurality of gears, each of which includes an input gear in transmission connection with the motor shaft and an output gear sleeved on the lead screw and in transmission connection with the lead screw. The angle sensor is used to detect the rotation angle of the output gear. The steering controller is used to: When the steering system drives the wheels of the electric vehicle to steer, the steering system receives an angle signal from the angle sensor and controls the speed or torque output by the steering motor according to the rotation angle of the output gear indicated by the angle signal.

13. The electric vehicle according to claim 12, characterized in that The angle sensor is a magnetic field sensor, which includes a magnet and a detection chip. The magnet rotates as the output gear rotates, and the detection chip determines the rotation angle of the output gear according to the rotation angle of the magnet.

14. The electric vehicle according to claim 13, characterized in that The steering system further includes a sensor mounting gear, which is meshed with the output gear and rotates along with the rotation of the output gear, and the magnet is mounted on the sensor mounting gear.

15. The electric vehicle according to claim 12, characterized in that The angle sensor is a resolver sensor, and the angle sensor includes an annular stator, which is sleeved on the lead screw.

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