CN117360621A

CN117360621A - Position sensor and steering device

Info

Publication number: CN117360621A
Application number: CN202310834152.0A
Authority: CN
Inventors: 䔓焕; 李慜暎; 文一起; 裵珍硕; 徐正郁
Original assignee: Halla Creedong Electronics Co ltd
Current assignee: Halla Creedong Electronics Co ltd
Priority date: 2022-07-07
Filing date: 2023-07-07
Publication date: 2024-01-09

Abstract

Position sensor and steering device. Comprising the following steps: a substrate; an initial axis extending from a first side to a second side of the substrate in a manner perpendicular to the substrate; a first initial gear provided on the initial shaft at a first side of the base plate; a second initial gear provided on the initial shaft at a second side of the base plate; a first servo axis provided on a first side of the substrate to be perpendicular to the substrate and parallel to the initial axis; a second servo axis which is separated from the first servo axis and is provided perpendicular to the substrate and parallel to the initial axis at a second side of the substrate; a first servo gear engaged with the first initial gear and provided on the first servo shaft at the first side of the base plate; a second servo gear engaged with the second initial gear and provided on the second servo shaft at the second side of the substrate; a first servo rotor provided on the first servo shaft on the first side of the substrate; a first induction coil; a second servo rotor provided on the second servo shaft on the second side of the substrate; and a second induction coil.

Description

Position sensor and steering device

Technical Field

The disclosed invention relates to a position sensor and a steering device capable of detecting the position and movement of a rack bar.

Background

In general, a steering device for controlling a traveling direction of a vehicle may include a steering wheel disposed on a driver's seat, a steering column connected to the steering wheel, a rack/pinion converting a rotational motion provided from the steering column into a linear motion, a rack bar connected to the rack, and the like.

Also, the steering device may include an angle sensor that measures a rotation angle of the steering column that rotates as the driver turns the steering wheel, and a torque sensor that measures a torque that the driver applies to the steering wheel in order to turn the steering wheel. The control device (electronic control unit, ECU) of the steering device can recognize the steering angle of the vehicle based on the output of the angle sensor and the torque sensor.

Recently, studies have been made to omit the mechanical connection between the steering wheel and the rack bar in the steering device. A steering device known as a so-called steer-by-wire (steering-by-wire) can detect rotation of a steering wheel using an angle sensor and a torque sensor and make a rack bar perform a linear motion using a motor.

Thus, since the mechanical connection between the steering wheel and the rack bar is omitted, a separate sensor for detecting the linear movement of the rack bar is required.

Disclosure of Invention

An object of an aspect of the disclosed invention is to provide a position sensor and a steering device capable of detecting the position and movement of a rack bar.

An object of an aspect of the disclosed invention is to provide a position sensor and a steering device capable of improving reliability, stability, and robustness of detecting a position and detecting movement.

A position sensor according to an aspect of the disclosed invention may include: a substrate; an initial (initial) axis extending from a first side to a second side of the substrate in a manner perpendicular to the substrate; a first initial gear provided on the initial shaft on a first side of the substrate; a second initial gear provided on the initial shaft on a second side of the substrate; a first servo (service) axis disposed on a first side of the substrate, perpendicular to the substrate and parallel to the initial axis; a second servo axis which is separated from the first servo axis and is arranged on a second side of the substrate to be perpendicular to the substrate and parallel to the initial axis; a first servo gear engaged with the first initial gear, the first servo gear being provided on the first servo shaft on the first side of the substrate; a second servo gear engaged with the second initial gear, the second servo gear being provided on the second servo shaft on the second side of the substrate; a first servo rotor provided on the first servo shaft on a first side of the substrate; a first induction coil provided on a first surface of a first side of the substrate; a second servo rotor provided on the second servo shaft on a second side of the substrate; and a second induction coil provided on a second surface of the second side of the substrate.

The first gear ratio between the first initial gear and the first servo gear may be different from the second gear ratio between the second initial gear and the second servo gear.

The diameter of the first initial gear may be different from the diameter of the second initial gear.

The diameter of the first servo gear may be different from the diameter of the second servo gear.

The diameter of the first initial gear may be larger than the diameter of the first servo gear, and the diameter of the second initial gear may be larger than the diameter of the second servo gear.

The first servo gear and the first servo rotor may rotate around a rotation axis of the first servo shaft, and the second servo gear and the second servo rotor may rotate around a rotation axis of the second servo shaft.

The virtual straight line extending from the rotation axis of the first servo rotor may pass through the center of the first induction coil, and the virtual straight line extending from the rotation axis of the second servo rotor may pass through the center of the second induction coil.

The first servo rotor may include a plurality of first rotor teeth provided on a circumference of the first servo rotor, and the second servo rotor may include a plurality of second rotor teeth provided on a circumference of the second servo rotor.

The first induction coil may be arranged in a zigzag manner between a virtual first circle having a first radius and a virtual second circle having a second radius larger than the first radius, and the second induction coil may be arranged in a zigzag manner between a virtual third circle having a third radius and a virtual fourth circle having a fourth radius larger than the third radius.

The radial width of each of the plurality of first rotor teeth may be the same as the difference between the second radius and the first radius, and the radial width of each of the plurality of second rotor teeth may be the same as the difference between the fourth radius and the third radius.

The circumferential width of each of the plurality of first rotor teeth may be the same as the interval between adjacent first rotor teeth, and the circumferential width of each of the plurality of second rotor teeth may be the same as the interval between adjacent second rotor teeth.

The position sensor may further include a processor electrically connected to the first induction coil and the second induction coil.

The processor may identify the impedance or the magnetic resistance of the first induction coil, identify the rotation angle of the first servo rotor based on the result of identifying the impedance or the magnetic resistance of the first induction coil, identify the impedance or the magnetic resistance of the second induction coil, and identify the rotation angle of the second servo rotor based on the result of identifying the impedance or the magnetic resistance of the second induction coil.

The processor may identify a rotation angle of the initial shaft based on a rotation angle of the first servo rotor and a rotation angle of the second servo rotor.

The primary shaft may be coupled to a rack assembly of a vehicle.

The steering apparatus according to an aspect of the disclosed invention may include: a rack bar assembly connected to wheels of a vehicle; a steering motor for providing a rotation for linearly moving the rack bar assembly; an angle sensor that recognizes a rotation angle of a steering column connected to a steering wheel of the vehicle; an initial shaft connected to the rack bar assembly; a position sensor that measures a rotation angle of the initial shaft; and a controller that controls the steering motor based on an output signal of the angle sensor and an output signal of the position sensor. The above-mentioned position sensor may include: a substrate perpendicular to the initial axis; a first initial gear provided on the initial shaft on a first side of the substrate; a second initial gear provided on the initial shaft on a second side of the substrate; a first servo axis perpendicular to the substrate and parallel to the initial axis on a first side of the substrate; a second servo axis which is separated from the first servo axis and is arranged on a second side of the substrate to be perpendicular to the substrate and parallel to the initial axis; a first servo gear engaged with the first initial gear, the first servo gear being provided on the first servo shaft on the first side of the substrate; a second servo gear engaged with the second initial gear, the second servo gear being provided on the second servo shaft on the second side of the substrate; a first servo rotor provided on the first servo shaft on a first side of the substrate; a first induction coil provided on a first surface of a first side of the substrate; a second servo rotor provided on the second servo shaft on a second side of the substrate; and a second induction coil provided on a second surface of the second side of the substrate.

A first gear ratio between the first initial gear and the first servo gear is different from a second gear ratio between the second initial gear and the second servo gear.

The diameter of the first initial gear may be different from the diameter of the second initial gear, and the diameter of the first servo gear may be different from the diameter of the second servo gear.

A processor may be included that is electrically connected to the first inductive coil and the second inductive coil. The processor recognizes an impedance or a magnetic resistance of the first induction coil, recognizes a rotation angle of the first servo rotor based on a result of recognizing the impedance or the magnetic resistance of the first induction coil, and recognizes an impedance or the magnetic resistance of the second induction coil, and recognizes a rotation angle of the second servo rotor based on a result of recognizing the impedance or the magnetic resistance of the second induction coil.

The processor may recognize a rotation angle of the initial shaft based on the rotation angle of the first servo rotor and the rotation angle of the second servo rotor, and provide an output signal corresponding to the rotation angle of the initial shaft to the controller.

Drawings

Fig. 1 shows an example of a steering device including a position sensor according to an embodiment.

Fig. 2 shows an upper perspective view of a position sensor according to an embodiment.

Fig. 3 shows a lower perspective view of a position sensor according to an embodiment.

FIG. 4 illustrates an exploded view of a position sensor according to an embodiment.

FIG. 5 illustrates a side view of a position sensor according to an embodiment.

Fig. 6 illustrates a first initial gear and a first servo gear included in a position sensor according to an embodiment.

Fig. 7 illustrates a second initial gear and a second servo gear included in a position sensor according to an embodiment.

Fig. 8 shows a first rotor and a first induction coil included in a position sensor according to an embodiment.

Fig. 9 shows a control structure of a position sensor according to an embodiment.

Fig. 10 shows an example of the rotation angle of the position sensor recognition shaft according to an embodiment.

Detailed Description

As shown in fig. 1, the steering apparatus 1 may include a steering wheel 10, a steering column 20, an angle sensor 30, a torque sensor 40, a rack bar assembly 50, a steering motor 60, a position sensor 100, or a steering controller 70. The structures shown in fig. 1 are not essential structures of the steering apparatus 1, and at least some of the structures shown in fig. 1 may be omitted.

The steering wheel 10 may obtain an input regarding the traveling direction of the vehicle or a steering wish of the driver (hereinafter referred to as "steering input") from the driver. The steering wheel 10 may be rotated in a clockwise direction or a counterclockwise direction according to a steering input of a driver.

The steering column 20 supports the steering wheel 10 and can be used as a rotation shaft of the steering wheel 10. The steering column 20 may rotate as the steering wheel 10 rotates.

The angle sensor 30 detects the rotation of the steering wheel 10 or the steering column 20 by the driver, and may measure the rotation angle of the steering wheel 10 or the steering column 20. The angle sensor 30 may provide an electrical signal corresponding to the measured rotation angle to the steering controller 70.

The torque sensor 40 detects rotation of the steering wheel 10 or the steering column 20, and may measure torque applied to the steering wheel 10 or the steering column 20 by the driver. The torque sensor 40 may provide an electrical signal corresponding to the measured torque to the steering controller 70.

The rack bar assembly 50 is connected to wheels of a vehicle, and can be linearly moved by driving of a steering motor 60. The rack bar assembly 50 may change the direction of the rotation axis of the wheels of the vehicle in order to change the traveling direction of the vehicle. For example, the rack bar assembly 50 may be linearly moved so that the rotation shaft of the wheel of the vehicle rotates in a counterclockwise direction. Thus, the vehicle can be steered to the left. Also, the rack bar assembly 50 may be linearly moved so that the rotation shaft of the wheel rotates in a clockwise direction. Thereby, the vehicle can be steered to the right.

The steering motor 60 is connected to the rack bar assembly 50 through a power conversion device, and may provide a rotational force for linearly moving the rack bar assembly 50. The steering motor 60 may provide a rotational force for linearly moving the rack bar assembly 50 to the left or right in response to control of the steering controller 70. For example, the rotation of the steering motor 60 may be converted into linear motion by a rack, a pinion, or the like.

The position sensor 100 detects the linear motion of the rack bar assembly 50 and can measure the displacement of the rack bar assembly 50. For example, the linear motion of the rack bar assembly 50 may be converted into a rotational motion by the rack 51 and the pinion 52, and the position sensor 100 may measure the displacement of the converted rotational motion. The position sensor 100 may provide an electrical signal to the steering controller 70 corresponding to the measured displacement of the rack bar assembly 50.

The steering controller 70 obtains detection signals output from the angle sensor 30, the torque sensor 40, and/or the position sensor 100, and can control the steering motor 60 based on the obtained detection signals.

For example, the steering controller 70 may identify a steering input and/or a steering intent of the driver based on the output signals of the angle sensor 30 and/or the torque sensor 40. The steering controller 70 may control the steering motor 60 to move the rack bar assembly 50 to the target position based on the identified steering input and/or steering intent.

The steering controller 70 may identify the measured position of the rack bar assembly 50 based on the output signal of the position sensor 100. The steering controller 70 compares the actual measurement position with the target position, and controls the steering motor 60 so that the actual measurement position of the rack bar assembly 50 follows the target position.

In this way, the angle sensor 30 can detect the steering input of the driver. Also, the position sensor 100 may detect the displacement of the rack bar assembly 50.

The angle sensor 30 and the position sensor 100 may perform the same or at least similar functions as identifying the rotation angle of the shaft. Also, the angle sensor 30 and the position sensor 100 may have the same or at least similar structures.

The specific structure and operation of the position sensor 100 will be described below, and the structure and operation of the base of the angle sensor 30 may be substantially the same as those described below.

Fig. 2 shows an upper perspective view of a position sensor according to an embodiment. Fig. 3 shows a lower perspective view of a position sensor according to an embodiment. FIG. 4 illustrates an exploded view of a position sensor according to an embodiment. FIG. 5 illustrates a side view of a position sensor according to an embodiment. Fig. 6 illustrates a first initial gear and a first servo gear included in a position sensor according to an embodiment. Fig. 7 illustrates a second initial gear and a second servo gear included in a position sensor according to an embodiment. Fig. 8 shows a first rotor and a first induction coil included in a position sensor according to an embodiment.

As shown in fig. 2, 3, 4, 5, 6, 7, and 8, the position sensor 100 may include an initial shaft 110, a first initial gear 111, a first servo shaft 120, a first servo gear 121, a first servo rotor 123, a first induction coil 151, a second initial gear 131, a second servo shaft 140, a second servo gear 141, a second servo rotor 143, a second induction coil 152, or a substrate 150. The structures shown in fig. 2 to 8 are not necessarily required for the position sensor 100, and at least a part of the structures shown in fig. 2 to 8 may be omitted.

The primary shaft 110 may be coupled to the rack bar assembly 50 by a power conversion device. The power conversion device may convert the linear motion of the rack bar assembly 50 into the rotational motion of the initial shaft 110. For example, the power conversion device may include a rack 51 and a pinion 52.

The primary shaft 110 may be rotationally movable with the linear movement of the rack assembly 50. For example, as the rack assembly 50 moves linearly in a first direction, the initial shaft 110 may rotate in a first rotational direction (clockwise). Also, as the rack bar assembly 50 moves linearly in a second direction different from the first direction, the initial shaft 110 may rotate in a second rotational direction (counterclockwise direction) different from the first rotational direction.

The initial axis 110 may be set to be substantially perpendicular to the substrate 150. Specifically, the preliminary shaft 110 may penetrate the substrate 150 through a through hole 150c formed in the substrate 150. The preliminary shaft 110 may extend from the first face 150a of the substrate 150 to the second face 150b of the substrate 150 through the through hole 150 c.

The first initial gear 111 is substantially cylindrical and may be provided on the first surface 150a side of the substrate 150.

The first preliminary gear 111 may be provided on the preliminary shaft 110 in such a manner as to rotate together with the preliminary shaft 110. Specifically, the first preliminary gear 111 may be provided on the same shaft as the preliminary shaft 110. Thus, the first initial gear 111 can rotate at the same rotational speed and in the same rotational direction as the initial shaft 110, centering on the same shaft as the rotational shaft of the initial shaft 110.

A plurality of first preliminary teeth 111a may be formed at the outer circumferential surface of the first preliminary gear 111. As the first preliminary gear 111 rotates, the plurality of first preliminary teeth 111a may rotationally move along the outer circumferential surface of the first preliminary gear 111.

The first servo gear 121 is substantially cylindrical and may be provided on the first surface 150a side of the substrate 150.

The first servo gear 121 may be provided on the first servo shaft 120. Wherein the first servo axis 120 may be disposed substantially parallel to the initial axis 110.

Specifically, the first servo gear 121 may be provided on the same shaft as the first servo shaft 120 in such a manner as to rotate together with the first servo shaft 120. Thus, the first servo gear 121 can rotate at the same rotational speed and in the same rotational direction as the first servo shaft 120, centering on the same axis as the rotational axis of the first servo shaft 120.

A plurality of first servo teeth 121a may be formed on the outer circumferential surface of the first servo gear 121. The plurality of first servo teeth 121a may be engaged with the plurality of first initial teeth 111a of the first initial gear 111. Specifically, the rotation of the first preliminary gear 111 may be transmitted to the first servo gear 121 through the plurality of first preliminary teeth 111a and the plurality of first servo teeth 121a.

The diameter D2 of the first servo gear 121 may be different from the diameter D1 of the first initial gear 111. Also, the number of the plurality of first servo teeth 121a formed on the outer circumferential surface of the first servo gear 121 may be different from the number of the plurality of first initial teeth 111a formed on the outer circumferential surface of the first initial gear 111.

As shown in fig. 6, the diameter D1 of the first preliminary gear 111 may be larger than the diameter D2 of the first servo gear 121. Also, the number of the plurality of first preliminary teeth 111a may be greater than the number of the plurality of first servo teeth 121a. For example, the ratio between the diameter D1 of the first initial gear 111 and the diameter D2 of the first servo gear 121 may be about 1.216:1. Also, the ratio between the number of the plurality of first initial teeth 111a and the number of the plurality of first servo teeth 121a may be about 1.216:1.

The first servo gear 121 rotates in mesh with the first initial gear 111, but the rotation speed of the first servo gear 121 may be different from that of the first initial gear 111. The rotation speed of the first servo gear 121 may be faster than the rotation speed of the first initial gear 111.

Further, the first initial gear 111 and the first servo gear 121 may be rotated at a certain gear ratio.

For example, the gear ratio between the first initial gear 111 and the first servo gear 121 may be about 1.216:1, and the rotation ratio between the first initial gear 111 and the first servo gear 121 may be about 1:1.216. In other words, during 1 rotation of the first initial gear 111, the first servo gear 121 may rotate about 1.216 rotations. Also, the first servo gear 121 may be rotated 360 degrees during the rotation of the first initial gear 111 by about 296 degrees.

The first servo rotor 123 may be provided in a substantially disk shape between the substrate 150 and the first servo gear 121 in the first surface 150a side of the substrate 150. In other words, the first surface 150a of the substrate 150 may be laminated in the order of the substrate 150, the first servo rotor 123, and the first servo gear 121.

The first servo rotor 123 may be provided on the first servo shaft 120 in a substantially disk shape. The first servo rotor 123 may be provided on the same shaft as the first servo shaft 120 in such a manner as to rotate together with the first servo shaft 120. Thus, the first servo rotor 123 can rotate at the same rotational speed and in the same rotational direction as the first servo shaft 120, centering on the same axis as the rotational axis of the first servo shaft 120. The first servo rotor 123 may rotate at the same rotational speed and in the same rotational direction as the first servo gear 121, with the same axis as the rotational axis of the first servo gear 121.

As shown in fig. 8, a plurality of first rotor teeth 123a may be formed at the outer circumference of the first servo rotor 123. A hollow may be formed between the plurality of first rotor teeth 123a.

The shape of the plurality of first rotor teeth 123a may be substantially the same. The shape of the hollow space between the plurality of first rotor teeth 123a may be substantially the same. In other words, the circumferential width and the circumferential interval of the plurality of first rotor teeth 123a may be substantially the same. Further, the circumferential width of each of the plurality of first rotor teeth 123a may be substantially the same as the circumferential interval between two adjacent first rotor teeth 123a.

For example, the first rotor teeth 123a may be formed periodically along the outer circumference of the first servo rotor 123. Also, during the rotation of the first rotor teeth 123a, the first rotor teeth 123a may periodically pass through the vicinity of a specific position of the substrate 150.

The diameter of the first servo rotor 123 is not limited. For example, the diameter of the first servo rotor 123 may be larger or the same as or smaller than the diameter of the first servo gear 121.

The first induction coil 151 may be provided on the first surface 150a of the substrate 150 in a substantially disk shape. The first induction coil 151 is fixed to the first surface 150a of the substrate 150 so as not to rotate together with the first servo shaft 120.

The first induction coil 151 may be arranged in a zigzag manner between circumferences of virtual circles having different radii. For example, as shown in fig. 8, the first induction coil 151 may be arranged in a zigzag manner between a virtual first circle 151a having a first radius and a virtual second circle 151b having a second radius greater than the first radius.

In other words, the distance between the center of the first induction coil 151 and the first induction coil 151 may be periodically changed. For example, the first induction coil 151 may extend from the circumference of the first circle 151a to the circumference of the second circle 151b, and from the circumference of the second circle 151b to the circumference of the first circle 151 a. Thus, the first induction coil 151 may repeatedly extend from the circumference of the first circle 151a to the circumference of the second circle 151b, and from the circumference of the second circle 151b to the circumference of the first circle 151 a.

The area occupied by the first induction coil 151 may be substantially the same as the area occupied by the plurality of first rotor teeth 123a of the first servo rotor 123. In other words, the plurality of first rotor teeth 123a of the first servo rotor 123 may be positioned corresponding to an annular region between the first circle 151a and the second circle 151b forming the first induction coil 151. The radial width of the first rotor teeth 123a may be substantially the same as the radial width of the ring shape between the first and second circles 151a and 151 b.

The center of the annular first induction coil 151 may be substantially the same as the rotation center of the first servo rotor 123. In other words, the virtual first straight line extending from the rotation axis of the first servo rotor 123 may pass through the center of the annular first induction coil 151.

The first servo rotor 123 may be disposed near the first induction coil 151. In other words, the first servo rotor 123 rotates around the center of the first induction coil 151 in the vicinity of the first induction coil 151.

Thus, by the rotation of the first servo rotor 123, the plurality of first rotor teeth 123a periodically pass through the vicinity of the first induction coil 151.

At this time, the first servo rotor 123 and the plurality of first rotor teeth 123a may be configured of a magnetic substance, and the plurality of first rotor teeth 123a as the magnetic substance periodically pass near the first induction coil 151, whereby the magnetic resistance of the first induction coil 151 may be periodically changed, and the impedance of the first induction coil 151 may be periodically changed. For example, the impedance or the magnetic resistance of the first induction coil 151 may be changed in accordance with a period of 1 rotation of the first servo rotor 123.

Accordingly, by measuring the periodic variation of the impedance or the magnetic resistance of the first induction coil 151, the rotation of the first servo rotor 123 can be recognized.

The second preliminary gear 131 may be disposed at the second face 150b side of the base plate 150. In other words, the second preliminary gear 131 may be provided on the opposite side of the first preliminary gear 111 with respect to the base plate 150.

The second initial gear 131 is substantially cylindrical and is provided on the initial shaft 110 so as to rotate together with the initial shaft 110. Specifically, the second preliminary gear 131 may be provided on the same shaft as the preliminary shaft 110. Thus, the second initial gear 131 can rotate at the same rotational speed and in the same rotational direction as the initial shaft 110, centering on the same shaft as the rotational shaft of the initial shaft 110.

A plurality of second preliminary teeth 131a may be formed at the outer circumferential surface of the second preliminary gear 131. As the second preliminary gear 131 rotates, the plurality of second preliminary teeth 131a may rotationally move along the outer circumferential surface of the second preliminary gear 131.

The second servo gear 141 may be provided at the second surface 150b side of the substrate 150. In other words, the second servo gear 141 may be provided on the opposite side of the first servo gear 121 with respect to the substrate 150.

The second servo gear 141 is substantially cylindrical and may be provided on the second servo shaft 140. Wherein the second servo axis 140 may be disposed substantially parallel to the initial axis 110. The second servo axis 140 may be detachable from the first servo axis 120. Further, the rotation axis of the second servo shaft 140 may be substantially the same as the rotation axis of the first servo shaft 120.

Specifically, the second servo gear 141 may be provided on the same shaft as the second servo shaft 140 in such a manner as to rotate together with the second servo shaft 140. Thus, the second servo gear 141 can rotate at the same rotational speed and in the same rotational direction as the second servo shaft 140, centering on the same axis as the rotational axis of the second servo shaft 140.

The outer circumferential surface of the second servo gear 141 may be formed with a plurality of second servo teeth 141a. The plurality of second servo teeth 141a may mesh with the plurality of second initial teeth 131a of the second initial gear 131. Specifically, the rotation of the second preliminary gear 131 may be transferred to the second servo gear 141 through the plurality of second preliminary teeth 131a and the plurality of second servo teeth 141a.

The diameter D4 of the second servo gear 141 may be different from the diameter D3 of the second preliminary gear 131. Also, the number of the plurality of second servo teeth 141a formed on the outer circumferential surface of the second servo gear 141 may be different from the number of the plurality of second initial teeth 131a formed on the outer circumferential surface of the second initial gear 131.

As shown in fig. 7, the diameter D3 of the second preliminary gear 131 may be greater than the diameter D4 of the second servo gear 141. Also, the number of the plurality of second preliminary teeth 131a may be greater than the number of the plurality of second servo teeth 141a. For example, the ratio between the diameter D3 of the second initial gear 131 and the diameter D4 of the second servo gear 141 may be about 9:1. Also, the ratio between the number of the plurality of second initial teeth 131a and the number of the plurality of second servo teeth 141a may be about 9:1.

The second servo gear 141 rotates in mesh with the second initial gear 131, but the rotation speed of the second servo gear 141 may be different from that of the second initial gear 131. The rotation speed of the second servo gear 141 may be faster than the rotation speed of the second preliminary gear 131. For example, the gear ratio of the second initial gear 131 to the second servo gear 141 may be about 9:1, and the rotation ratio of the second initial gear 131 to the second servo gear 141 may be about 1:9. In other words, during 1 rotation of the second preliminary gear 131, the second servo gear 141 may rotate about 9 rotations. Also, the second servo gear 141 may be rotated 360 degrees during the rotation of the second initial gear 131 by about 40 degrees.

As explained above, the gear ratio of the first initial gear 111 to the first servo gear 121 may be about 1.216:1, and during 1 revolution of the first initial gear 111, the first servo gear 121 may rotate about 1.216 revolutions. At this time, the first and second initial gears 111 and 131 are all provided on the initial shaft 110, and the same rotation as the initial shaft 110 is possible.

Accordingly, the rotation ratio of the first servo gear 121 to the second servo gear 141 may be about 1.216:9 (=1:7.4). Specifically, during 5 rotations of the first servo gear 121, the second servo gear 141 may rotate 37 rotations.

In other words, the first servo gear 121 may be rotated 5 turns and the second servo gear 141 may be rotated 37 turns while the first servo gear 121 and the second servo gear 141 are all returned to the reference position again after the first servo gear 121 and the second servo gear 141 are simultaneously rotated from the reference position.

Also, during 5 rotations of the first servo gear 121, the first initial gear 111 may be rotated 1480 degrees. Also, during the 37 rotations of the second servo gear 141, the second initial gear 131 may be rotated 1480 degrees. The rotation of the first and second preliminary gears 111 and 131 may be the same as the rotation of the preliminary shaft 110. Thus, the initial shaft 110 can be rotated 1480 degrees while all of the first and second servo gears 121 and 141 are returned to the reference positions again after the first and second servo gears 121 and 141 are simultaneously rotated from the reference positions.

Thus, through a combination of the rotation angle of the first servo gear 121 and the rotation angle of the second servo gear 141, the rotation of the initial shaft 110 to 1480 degrees can be recognized.

The second servo rotor 143 has a substantially disk shape, and is provided between the substrate 150 and the second servo gear 141 on the second surface 150b side of the substrate 150. In other words, the second surface 150b of the substrate 150 may be laminated in the order of the substrate 150, the second servo rotor 143, and the second servo gear 141.

The second servo rotor 143 may be provided on the second servo shaft 140 in a substantially disk shape. The second servo rotor 143 may be provided on the same shaft as the second servo shaft 140 in such a manner as to rotate together with the second servo shaft 140. Thus, the second servo rotor 143 can rotate at the same rotation speed and in the same rotation direction as the second servo shaft 140, centering on the same axis as the rotation axis of the second servo shaft 140. The second servo rotor 143 may rotate at the same rotational speed and in the same rotational direction as the second servo gear 141, centering on the same axis as the rotational axis of the second servo gear 141.

The shape of the second servo rotor 143 may be the same as the shape of the first servo rotor 123 shown in fig. 8.

The second induction coil 152 may be provided on the second surface 150b of the substrate 150 in a substantially disk shape. The second induction coil 152 is fixed to the second surface 150b of the substrate 150 so as not to rotate together with the second servo shaft 140.

The second induction coil 152 may be arranged in a zigzag manner between circumferences of virtual circles having different radii. For example, the second induction coil 152 may be arranged in a zigzag manner between a virtual third circle having a third radius and a virtual fourth circle having a fourth radius greater than the third radius. Also, the shape of the second induction coil 152 may be the same as the shape of the first induction coil 151 shown in fig. 8.

The center of the ring-shaped second induction coil 152 may be substantially the same as the rotation center of the second servo rotor 143. In other words, the virtual second straight line extending from the rotation axis of the second servo rotor 143 may pass through the center of the ring-shaped second induction coil 152.

The second servo rotor 143 may be disposed near the second induction coil 152. In other words, the second servo rotor 143 may rotate around the center of the second induction coil 152 in the vicinity of the second induction coil 152.

Thus, by the rotation of the second servo rotor 143, the plurality of second rotor teeth 143a can periodically pass near the second induction coil 152.

At this time, the second servo rotor 143 and the plurality of second rotor teeth 143a may be formed of a magnetic substance, the second rotor teeth 143a as the magnetic substance periodically pass near the second induction coil 152, whereby the magnetic resistance of the second induction coil 152 periodically changes, and the impedance of the second induction coil 152 may periodically change. For example, the impedance or reluctance of the second induction coil 152 may be changed in accordance with a period in which the second rotor tooth 143a rotates by 1 turn.

Accordingly, by measuring the periodic variation of the impedance or the magnetic resistance of the second induction coil 152, the rotation of the second servo rotor 143 can be recognized. By measuring the periodic variation of the impedance or the magnetic resistance of the first induction coil 151, the rotation of the first servo rotor 123 can be recognized.

The rotation of the first servo rotor 123 may be the same as the rotation of the first servo gear 121, and the rotation of the second servo rotor 143 may be the same as the rotation of the second servo gear 141.

Further, as described above, the rotation of the initial shaft 110 to 1480 degrees can be recognized by the combination of the rotation angle of the first servo gear 121 and the rotation angle of the second servo gear 141. Thus, rotation of the initial shaft 110 to 1480 degrees can be identified by the periodic variation of the impedance or reluctance of the first inductive coil 151 and the periodic variation of the impedance or reluctance of the second inductive coil 152.

As described above, the position sensor 100 may include the initial shaft 110 rotated according to the linear movement of the rack bar assembly 50, the first servo shaft 120 rotated according to a first ratio with respect to the rotation of the initial shaft 110, the first servo rotor 123 rotated together with the first servo shaft 120, the first induction coil 151 whose resistance or magnetic resistance varies according to the rotation of the first servo rotor 123, the second servo shaft 140 rotated according to a second ratio with respect to the rotation of the initial shaft 110, the second servo rotor 143 rotated together with the second servo shaft 140, and the second induction coil 152 whose resistance or magnetic resistance varies according to the rotation of the second servo rotor 143.

By measuring the change in the impedance or magnetic resistance of the first induction coil 151 and the change in the impedance or magnetic resistance of the second induction coil 152, the rotation angle of the initial shaft 110 can be recognized, and the linear displacement of the rack bar assembly 50 can be recognized.

Next, a configuration for measuring a change in impedance or magnetic resistance of the first induction coil 151 and a change in impedance or magnetic resistance of the second induction coil 152 will be described.

Fig. 9 shows a control structure of a position sensor according to an embodiment. Fig. 10 shows an example of the rotation angle of the position sensor recognition shaft according to an embodiment.

As shown in fig. 9, the position sensor 100 may include a first induction coil 151, a second induction coil 152, and a processor 160.

As shown in fig. 8 described above, in the annular region between the first circle 151a having the first radius and the second circle 151b having the second radius, the first induction coils 151 may be arranged in a zigzag manner along the circumferential direction. In other words, the distance between the center of the first induction coil 151 and the first induction coil 151 may be periodically changed.

The first servo rotor 123 may be rotatably provided near the first induction coil 151. The impedance or the magnetic resistance of the first induction coil 151 may be periodically changed by the rotation of the first servo rotor 123. For example, during the rotation of the first servo rotor 123 as a magnetic body, the first rotor tooth 123a portion of the first servo rotor 123 corresponding to the inner region of the first induction coil 151 may be periodically changed. Whereby the magnetic resistance of the first induction coil 151 is periodically changed, and the first induction coil 151 can periodically sense an induction current.

The second induction coil 152 may have the same structure as the first induction coil 151 described above.

The second servo rotor 143 may be rotatably provided near the second induction coil 152. The impedance or the magnetic resistance of the second induction coil 152 may be periodically changed by the rotation of the second servo rotor 143.

The processor 160 may identify the impedance or reluctance (or periodic variation thereof) of the first inductive coil 151 and the impedance or reluctance (or periodic variation thereof) of the second inductive coil 152.

For example, the processor 160 may measure the first and second induced currents induced in the respective first and second induction coils 151 and 152. The processor 160 may identify the magnetic resistance (or a change thereof) of the first induction coil 151 and the magnetic resistance (or a change thereof) of the second induction coil 152 based on the first induction current and the second induction current.

As another example, the processor 160 may periodically apply a voltage signal to each of the first and second induction coils 151 and 152, thereby measuring the current of each of the first and second induction coils 151 and 152. The processor 160 may identify the impedance of the first inductive coil 151 (or a change thereof) and the impedance of the second inductive coil 152 (or a change thereof) based on the respective currents of the first inductive coil 151 and the second inductive coil 152.

The processor 160 may identify the rotation angle of the first servo rotor 123 based on the identified result of the impedance or reluctance (or the periodic variation thereof) of the first induction coil 151. And, the processor 160 may recognize the rotation angle of the second servo rotor 143 based on the recognized result of the impedance or the reluctance (or the periodic variation thereof) of the second induction coil 152.

For example, the processor 160 may identify that the first servo rotor 123 rotates 1 turn based on a periodic variation of the impedance or reluctance of the first induction coil 151. And, the processor 160 may recognize that the second servo rotor 143 rotates 1 turn based on a periodic variation of the impedance or the reluctance of the second induction coil 152.

The processor 160 may recognize the rotation angle of the initial shaft 110 based on the rotation angle of the first servo rotor 123 and the rotation angle of the second servo rotor 143.

As described above, the rotation ratio between the initial shaft 110 and the first servo rotor 123 may be set according to a preset gear ratio between the first initial gear 111 and the first servo gear 121. For example, the rotation ratio between the initial shaft 110 and the first servo rotor 123 may be about 1:1.216. In other words, as shown in fig. 10, during the rotation of the first servo rotor 123 by 360 degrees (the rotation angle of the y-axis), the initial shaft 110 may be rotated by about 296 degrees (the rotation angle of the x-axis).

Also, the rotation ratio between the initial shaft 110 and the second servo rotor 143 may be set according to a preset gear ratio between the second initial gear 131 and the second servo gear 141. For example, the rotation ratio between the initial shaft 110 and the second servo rotor 143 may be about 1:9. In other words, as shown in fig. 10, during the rotation of the second servo rotor 143 by 360 degrees (the rotation angle of the y-axis), the initial shaft 110 may be rotated by about 40 degrees (the rotation angle of the x-axis).

The rotation angle of the first servo rotor 123 and the rotation angle of the second servo rotor 143 may both correspond to the rotation angle of the initial shaft 110. For example, as shown in fig. 10, when the rotation angle of the initial shaft 110 is "0", the rotation angle of the first servo rotor 123 is "0", and the rotation angle of the second servo rotor 143 is "0". Thereafter, when the rotation angle of the first servo rotor 123 and the second servo rotor 143 are both "0", the rotation angle of the initial shaft 110 is "1480".

Accordingly, when the rotation angle of the initial shaft 110 is between "0" degrees and "1480" degrees, the rotation angle of the initial shaft 110 may correspond to both the rotation angle of the inherent first servo rotor 123 and the rotation angle of the second servo rotor 143. In other words, the rotation angle of the initial shaft 110 between "0" degrees and "1480" degrees can be recognized from both the rotation angle of the first servo rotor 123 and the rotation angle of the second servo rotor 143.

In this way, the processor 160 recognizes the rotation angle of the initial shaft 110 in a preset angle range (e.g., from "0" degree to "1480" degree) based on the recognized result of the impedance or magnetic resistance (or the periodic variation thereof) of the first induction coil 151 and the impedance or magnetic resistance (or the periodic variation thereof) of the second induction coil 152.

And, the processor 160 may provide the identified rotation angle of the initial shaft 110 to the steering controller 70 of the steering apparatus 1.

As described above, the steering controller 70 may identify the measured position of the rack bar assembly 50 based on the output signal of the position sensor 100. Further, the steering controller 70 compares the measured position with the target position, and may control the steering motor 60 such that the measured position of the rack bar assembly 50 follows the target position.

The angle sensor 30 of the steering device 1 can have substantially the same configuration and function as the position sensor 100. The position sensor 100 recognizes the rotation angle of the initial shaft 110 connected to the rack bar assembly 50, and the angle sensor 30 can recognize the rotation angle of the steering column 20 connected to the steering wheel 10.

According to an aspect of the disclosed invention, an object is to provide a position sensor and a steering device capable of detecting the position and movement of a rack bar.

According to an aspect of the disclosed invention, an object is to provide a position sensor and a steering device capable of improving reliability, stability, and robustness of detecting a position and detecting movement.

Claims

1. A position sensor, comprising:

a substrate;

an initial axis extending from a first side to a second side of the substrate in a manner perpendicular to the substrate;

a first initial gear provided on the initial shaft on a first side of the substrate;

a second initial gear provided on the initial shaft on a second side of the substrate;

a first servo axis perpendicular to the substrate and parallel to the initial axis on a first side of the substrate;

a second servo axis which is separated from the first servo axis and is arranged on a second side of the substrate to be perpendicular to the substrate and parallel to the initial axis;

a first servo gear engaged with the first initial gear, the first servo gear being provided on the first servo shaft on the first side of the substrate;

a second servo gear engaged with the second initial gear, the second servo gear being provided on the second servo shaft on the second side of the substrate;

a first servo rotor provided on the first servo shaft on a first side of the substrate;

A first induction coil provided on a first surface of a first side of the substrate;

a second servo rotor provided on the second servo shaft on a second side of the substrate; and

and a second induction coil provided on a second surface of the second side of the substrate.

2. The position sensor of claim 1, wherein,

3. The position sensor of claim 1, wherein,

the diameter of the first initial gear is different from the diameter of the second initial gear.

4. The position sensor of claim 1, wherein,

the diameter of the first servo gear is different from the diameter of the second servo gear.

5. The position sensor of claim 1, wherein,

the diameter of the first initial gear is larger than the diameter of the first servo gear,

the diameter of the second initial gear is larger than that of the second servo gear.

6. The position sensor of claim 1, wherein,

the first servo gear and the first servo rotor rotate around a rotation axis of the first servo shaft,

The second servo gear and the second servo rotor rotate around a rotation axis of the second servo shaft.

7. The position sensor of claim 1, wherein,

a virtual straight line extending from the rotation axis of the first servo rotor passes through the center of the first induction coil,

a virtual straight line extending from the rotation axis of the second servo rotor passes through the center of the second induction coil.

8. The position sensor of claim 1, wherein,

the first servo rotor includes a plurality of first rotor teeth provided on a circumference of the first servo rotor,

the second servo rotor includes a plurality of second rotor teeth provided on a circumference of the second servo rotor.

9. The position sensor of claim 8, wherein,

the first induction coil is arranged in a zigzag manner between a virtual first circle having a first radius and a virtual second circle having a second radius larger than the first radius,

the second induction coil is arranged in a zigzag manner between a virtual third circle having a third radius and a virtual fourth circle having a fourth radius larger than the third radius.

10. The position sensor of claim 9, wherein,

The width of each of the plurality of first rotor teeth in the radial direction is the same as the difference between the second radius and the first radius,

the radial width of each of the plurality of second rotor teeth is equal to the difference between the fourth radius and the third radius.

11. The position sensor of claim 8, wherein,

the circumferential width of each of the plurality of first rotor teeth is the same as the interval between adjacent first rotor teeth,

the circumferential width of each of the plurality of second rotor teeth is the same as the interval between adjacent second rotor teeth.

12. The position sensor of claim 1, wherein,

the position sensor further includes a processor electrically connected to the first induction coil and the second induction coil.

13. The position sensor of claim 12, wherein,

the processor identifies the impedance or reluctance of the first induction coil,

the processor recognizes a rotation angle of the first servo rotor based on a result of recognizing the impedance or the magnetic resistance of the first induction coil,

the processor identifies the impedance or reluctance of the second inductive coil,

The processor recognizes a rotation angle of the second servo rotor based on a result of recognizing the impedance or the magnetic resistance of the second induction coil.

14. The position sensor of claim 13, wherein,

the processor recognizes a rotation angle of the initial shaft based on the rotation angle of the first servo rotor and the rotation angle of the second servo rotor.

15. The position sensor of claim 1, wherein,

the initial shaft is connected with a toothed bar assembly of the vehicle.

16. A steering apparatus, comprising:

a rack bar assembly connected to wheels of a vehicle;

a steering motor for providing a rotation for linearly moving the rack bar assembly;

an angle sensor that recognizes a rotation angle of a steering column connected to a steering wheel of the vehicle;

an initial shaft connected to the rack bar assembly;

a position sensor that measures a rotation angle of the initial shaft; and

a controller for controlling the steering motor based on the output signal of the angle sensor and the output signal of the position sensor,

the position sensor includes:

a substrate perpendicular to the initial axis;

17. The steering device according to claim 16, wherein,

18. The steering device according to claim 16, wherein,

the diameter of the first initial gear is different from the diameter of the second initial gear,

19. The steering device according to claim 16, wherein,

the position sensor further includes a processor electrically coupled to the first inductive coil and the second inductive coil,

20. The steering device according to claim 19, wherein,

the processor recognizes the rotation angle of the initial shaft based on the rotation angle of the first servo rotor and the rotation angle of the second servo rotor,

the processor provides an output signal corresponding to the rotation angle of the initial shaft to the controller.