JP2013092461A - Sensor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sensor device that can be made compact along the axis of a rotary shaft even when detecting torque imparted to the rotary shaft and the angle of rotation of the rotary shaft.SOLUTION: A sensor device 14 includes a torque sensor 40 which is arranged along an input shaft 20 and a lower shaft 20 connected to each other through a torsion bar 22, and detects torque imparted to the input shaft 20, and a rotational angle sensor 50 which is arranged closely to an outer periphery of the torque sensor 40 in radial directions of the shafts 20, 21. The rotational angle sensor 50 includes a detection gear 52 which rotates as the lower shaft 21 rotates, and a sensor body 51 as a part for detecting the angle of rotation of the detection gear 52. Then the rotational angle sensor 50 detects the angle of rotation of the lower shaft 21 on the basis of the angle of rotation of the detection gear 52 detected through the sensor body 51.

Description

  The present invention relates to a sensor device capable of detecting torque applied to a rotation shaft and a rotation angle of the rotation shaft.

  2. Description of the Related Art A so-called electric power steering device is known in which an electric motor is provided on a steering shaft or a rack shaft of a vehicle, and assisting a driver's steering operation by applying an assist force from the electric motor to the steering shaft or the rack shaft. In this electric power steering apparatus, a target torque is set based on a steering torque detected through a torque sensor provided on a steering shaft, and the drive amount (assist amount) of the electric motor is controlled to generate the target torque. . In such an electric power steering apparatus, generally, the steering shaft is divided into an input shaft coupled to the steering wheel and a lower shaft coupled to the drive wheels via a rack shaft or the like, and each shaft Are connected to each other via a torsion bar. As a result, when steering torque is input to the input shaft as the steering wheel is operated, torsional deformation corresponding to the steering torque occurs in the torsion bar. That is, relative rotational displacement occurs in the input shaft and the lower shaft. The torque sensor is usually arranged so as to surround the input shaft and the lower shaft, and detects the steering torque by detecting the relative rotational displacement of each shaft.

  By the way, in the middle of the steering shaft of the vehicle, in order to execute various control of the vehicle, the rotation angle of the steering shaft is detected over a plurality of rotations, that is, the rotation angle that detects the steering angle that is the absolute angle of the steering shaft. A sensor may be provided. When this type of rotation angle sensor is disposed on the steering shaft together with the torque sensor described above, there is a problem that the length of the installation space occupied by these sensors in the axial direction of the steering shaft becomes long. In particular, in the middle of the steering shaft, there is a case where an energy absorbing mechanism is provided that absorbs impact energy applied during a frontal collision of the vehicle by shortening to telescopic under a substantially constant resistance over a predetermined stroke. In such a case, it is necessary to ensure a long shortening stroke of the steering shaft that contributes to energy absorption. Therefore, it is required to shorten the axial lengths of the torque sensor and the rotation angle sensor described above as much as possible.

  Therefore, conventionally, as seen in Patent Document 1, for example, a rotation angle sensor and a torque sensor are arranged adjacent to each other along the axial direction of the steering shaft, and a part of each component of each sensor is integrated. Such a method has been proposed. Thereby, since the installation space of each sensor in the axial direction of the steering shaft can be reduced, it is possible to reduce the size of the sensor device mounted on the electric power steering device.

JP 2007-271565 A

  Thus, if a part of each component of the rotation angle sensor and the torque sensor is integrated, the installation space for each sensor can surely be reduced. However, since it is necessary to secure the installation space for each sensor along the axial direction of the steering shaft, it cannot be said that the sensor device is sufficiently downsized in the axial direction, and there is still room for improvement. It has become.

  Such a problem is not limited to a sensor device mounted on an electric power steering device, but is a problem common to sensor devices capable of detecting the torque applied to the rotation shaft and the rotation angle of the rotation shaft. is there.

  The present invention has been made in view of such circumstances, and the purpose thereof is to reduce the size in the axial direction of the rotating shaft even when the torque applied to the rotating shaft and the rotation angle of the rotating shaft are detected. It is an object of the present invention to provide a sensor device that can handle the above.

  In order to solve the above-mentioned problem, the invention according to claim 1 is arranged along the first and second rotating shafts coaxially connected via a torsion bar, and the first and second rotating shafts are arranged. A torque sensor that detects the torque by detecting a relative rotational displacement that occurs between any one of the rotation shafts when torque is applied thereto, and an outer periphery of the torque sensor in a radial direction of the rotation shaft A rotation angle sensor disposed in proximity to the detection gear, the rotation angle sensor rotating based on rotation of one of the first and second rotation shafts, and rotation of the detection gear A sensor body that is a part for detecting an angle, and detecting a rotation angle of one of the first and second rotation shafts based on a rotation angle of the detection gear detected through the sensor body. Is the gist.

  According to this configuration, since the rotation angle sensor is arranged in parallel with the torque sensor in the radial direction of the first and second rotation shafts, the installation space for the rotation angle sensor in the axial direction of each rotation shaft can be reduced. Can do. For this reason, it becomes possible to reduce the size of the sensor device in the axial direction of each rotating shaft.

  According to a second aspect of the present invention, in the sensor device according to the first aspect, the torque sensor forms a first magnetism to be applied to the torque sensor magnetic detector and the torque sensor magnetic detector. And a first magnetic change caused by cooperation of relative rotational displacements of the first and second rotating shafts through the torque sensor magnetic detection unit. A relative rotational displacement of the first and second rotating shafts is detected, and the detection gear is provided with a quadrupole magnet, and the sensor body is disposed to face the quadrupole magnet. A rotation angle sensor for detecting the second magnetism formed by the same quadrupole magnet, and the rotation angle sensor changes the second magnetism based on the rotation of the detection gear. Detected through magnetic detector for rotation angle sensor And summarized in that in order to detect one of the rotation angle one of the first and second axis of rotation by Rukoto.

  As the torque sensor and the rotation angle sensor, for example, it is conceivable to use a magnetic sensor that performs sensing using magnetism formed by a magnet or a coil. In this case, as described above, when the rotation angle sensor is arranged close to the outer periphery of the torque sensor, the magnetism formed in the rotation angle sensor is detected on the torque sensor side, and the sensing accuracy of the torque sensor is lowered. There is a fear. In this regard, as described above, if a quadrupole magnet is used as a member for forming magnetism in the rotation angle sensor, the diffusion of magnetism to the surroundings can be suppressed, so that magnetic interference with the torque sensor is prevented. Can be suppressed. For this reason, even when a magnetic sensor is used as the torque sensor and the rotation angle sensor, it is possible to accurately maintain the sensing accuracy of the torque sensor.

The gist of the invention according to claim 3 is that, in the sensor device according to claim 2, a magnetic shielding member is provided between the torque sensor and the quadrupole magnet.
According to this configuration, since the magnetism formed in the quadrupole magnet of the rotation angle sensor can be shielded by the magnetic shielding member, magnetic interference to the torque sensor can be further suppressed. For this reason, it becomes possible to maintain the sensing accuracy of the torque sensor more accurately.

  According to a fourth aspect of the present invention, in the sensor device according to the second or third aspect, the magnetic forming portion is formed of a cylindrical magnet attached to an outer periphery of the first rotating shaft, The torque sensor includes a yoke disposed so as to surround the cylindrical magnet, and a cylindrical holding member that holds the yoke and rotates integrally with the second rotating shaft, When a relative rotational displacement occurs on the second rotation shaft, a magnetic change generated in the yoke based on the relative rotational displacement of the cylindrical magnet and the holding member is transmitted through the torque sensor magnetic detection unit. Detecting the relative rotational displacement of the first and second rotating shafts by detection, external teeth for meshing the detection gear are formed on the outer peripheral surface of the holding member. Is the gist.

  As in the same configuration, if an external tooth that engages the detection gear is formed on the holding member that is a component of the torque sensor, an additional gear that engages the detection gear is connected to the first rotation shaft or the first rotation shaft. Since there is no need to provide the second rotating shaft, the number of parts can be reduced. For this reason, the structure can be simplified.

  According to a fifth aspect of the present invention, in the sensor device according to the fourth aspect, the holding member is integrally assembled with the second rotating shaft by press-fitting the second rotating shaft therein. The gist of the invention is that the external teeth are formed on an outer peripheral surface of a portion of the holding member into which the second rotation shaft is press-fitted.

  As in the same configuration, when the second rotating shaft is press-fitted inside the holding member, if external teeth are formed on the outer peripheral surface of the portion where the second rotating shaft is press-fitted in the holding member, While providing the holding member with external teeth, the length of the holding member in the axial direction of each rotating shaft can be made as short as possible. For this reason, it is possible to reduce the size of the sensor device.

  According to the sensor device of the present invention, it is possible to reduce the size in the axial direction of the rotating shaft even when the torque applied to the rotating shaft and the rotation angle of the rotating shaft are detected.

BRIEF DESCRIPTION OF THE DRAWINGS The block diagram which shows the schematic structure about one Embodiment of the electric power steering apparatus of the vehicle to which the sensor apparatus concerning this invention is applied. Sectional drawing which shows the cross-sectional structure about the sensor apparatus of the embodiment. The perspective view which shows the disassembled perspective structure of the torque sensor about the sensor apparatus of the embodiment. The development which developed the 1st and 2nd yoke and cylindrical magnet on the plane about the torque sensor. (A), (b) is an expanded view which shows the operation example of the torque sensor. The perspective view which expands and shows the attachment part of the rotation angle sensor about the sensor apparatus of the embodiment. Sectional drawing which shows the cross-section around the rotation angle sensor about the sensor apparatus of the embodiment. Sectional drawing which shows the cross-section along the AA line of FIG. Sectional drawing which shows the cross-sectional structure about the other example of the electric power steering apparatus of the vehicle to which the sensor apparatus concerning this invention is applied.

  Hereinafter, an embodiment in which a sensor device according to the present invention is applied to a sensor device mounted on an electric power steering device of a vehicle will be described with reference to FIGS. First, the outline of the electric power steering apparatus for a vehicle according to the present embodiment will be described with reference to FIG.

  As shown in FIG. 1, in the vehicle, when the steering wheel 1 is operated by the driver, the steering shaft 2 rotates based on the steering force applied to the steering wheel 1. The steering shaft 2 is formed by connecting a column shaft 3, an intermediate shaft 4, and a pinion shaft 5. A rack and pinion mechanism 6 is connected to the end of the pinion shaft 5, and the rotation of the steering shaft 2 is converted into a reciprocating linear motion of the rack shaft 7 via the rack and pinion mechanism 6. The reciprocating linear motion of the rack shaft 7 is transmitted to the steered wheels 9 via the tie rods 8 connected to both ends thereof, thereby changing the steered angle of the steered wheels 9, that is, the traveling direction of the vehicle.

  In such a vehicle, the electric power steering apparatus 10 includes an electric motor 11 connected to the column shaft 3 via a gear mechanism 12. The electric power steering device 10 applies the motor torque as an assist force to the steering shaft 2 by decelerating the rotation of the electric motor 11 through the gear mechanism 12 and transmitting it to the column shaft 3.

  Further, the vehicle is provided with various sensors that detect the state of the vehicle and the operation amount of the steering wheel 1. For example, the vehicle is provided with a vehicle speed sensor 13 that detects the speed of the vehicle. The column shaft 3 is provided with a sensor device 14 that detects torque (steering torque) acting on the shaft and an absolute rotation angle (steering angle) of the shaft. And the output of the vehicle speed sensor 13 and the sensor apparatus 14 is input into the control apparatus 15 comprised centering on a microcomputer. The control device 15 sets a target torque, which is a target value of the driver's steering torque, based on the vehicle speed and the steering torque detected through the vehicle speed sensor 13 and the sensor device 14. Then, feedback control is performed on the current flowing through the electric motor 11 so that the steering torque detected through the sensor device 14 becomes the target torque. Note that the steering angle detected through the sensor device 14 is used for executing various types of vehicle control such as, for example, control for preventing a side slip of the vehicle in an ESC (Electronic Stability Control) system. .

Next, the structure of the sensor device 14 will be described with reference to FIG.
As shown in FIG. 2, the column shaft 3 has an input shaft 20 connected to the steering wheel 1 and a lower shaft 21 connected to the intermediate shaft 4 connected to the coaxial line m via a torsion bar 22. It consists of a structure. In the present embodiment, the input shaft 20 serves as the first rotating shaft, and the lower shaft 21 serves as the second rotating shaft. Among these, the input shaft 20 is coupled to the torsion bar 22 via the coupling pin 23 and is rotatably supported by a bearing (not shown) provided above the case 30. The lower shaft 21 is coupled to the torsion bar 22 via the coupling pin 24 and is rotatably supported by a bearing 31 provided below the case 30. In the column shaft 3, when a steering torque is applied to the input shaft 20 as the steering wheel 1 is operated, the steering torque is transmitted from the input shaft 20 to the lower shaft 21 via the torsion bar 22. Torsional deformation occurs in the torsion bar 22. As a result, a relative rotational displacement corresponding to the steering torque is generated between the input shaft 20 and the lower shaft 21. The sensor device 14 includes a torque sensor 40 that detects a steering torque based on the relative rotational displacement between the input shaft 20 and the lower shaft 21, and a steering angle by detecting the rotation angle of the lower shaft 21. And a rotation angle sensor 50 for detecting.

  Among these, the torque sensor 40 is disposed along the input shaft 20 and the lower shaft 21. The torque sensor 40 includes a cylindrical magnet 41 as a magnetic forming portion attached to the outer peripheral surface of the input shaft 20, first and second yokes 43 and 44 arranged so as to surround the cylindrical magnet 41, and these The first and second magnetism collecting rings 45 and 46 for guiding the magnetism generated in the yokes 43 and 44 to the magnetic sensor 47 are provided. The first and second yokes 43 and 44 are held by being integrally molded by a first holding member 48 made of a resin member. Further, the first and second magnetism collecting rings 45 and 46 are held by being integrally molded by a second holding member 49 made of a resin member.

  Here, when the exploded perspective structure of the torque sensor 40 is shown in FIG. 3, the cylindrical magnet 41 is composed of a multipolar magnet in which N poles and S poles are alternately arranged in the circumferential direction. In FIG. 3, the first and second holding members 48 and 49 are omitted for convenience.

  The first and second yokes 43, 44 are formed on the annular portions 43 a, 44 a surrounding the circumference of the cylindrical magnet 41, and the inner peripheral surface of the annular portion 43 a, and are arranged in the axial direction of the column shaft 3 ( A plurality of triangular claw portions 43b and 44b that are bent in a direction indicated by an arrow a in FIG. Among these, the claw portions 43b and 44b are bent in parallel to the axial directions of the input shaft 20 and the lower shaft 21 and in opposite directions. Further, FIG. 4 is a diagram in which the first and second yokes 43 and 44 and the cylindrical magnet 41 are developed on a plane, and the claw portions 43b and 44b are arranged in the radial direction of the column shaft 3 (arrow b in FIG. Are alternately arranged along the direction indicated by.

  On the other hand, as shown in FIG. 2, the lower end portion of the first holding member 48 is provided with a press-fit portion 48 b whose inner diameter is set smaller than the portion surrounding the cylindrical magnet 41. The first holding member 48 is assembled to the lower shaft 21 by press-fitting the upper end portion of the lower shaft 21 therein. As a result, the first holding member 48 rotates integrally with the lower shaft 21 about the axis m.

  Further, as shown in FIG. 3, the first and second magnetic flux collecting rings 45 and 46 are made of an annular magnetic member. As shown in FIG. 2, these magnetism collecting rings 45, 46 are arranged to face the outer edges of the first and second yokes 43, 44 exposed from the outer peripheral surface of the first holding member 48. . Thereby, the magnetism generated in the first and second yokes 43 and 44 is guided to the first and second magnetic flux collecting rings 45 and 46. Further, as shown in FIG. 3, the first and second magnetic flux collecting rings 45 and 46 include magnetic flux collecting portions 45 a and 46 a that are opposed to each other with a predetermined gap therebetween. Between these magnetic flux collectors 45a and 46a, a magnetic sensor serving as a magnetic sensor for a torque sensor is configured with a Hall element that outputs a voltage signal corresponding to the strength of the applied magnetism (magnetic field) as a result of the Hall effect. 47 is arranged. As a result, when magnetism is induced from the first and second yokes 43, 44 to the first and second magnetism collecting rings 45, 46, a leakage flux is generated between the magnetism collecting portions 45a, 46a. It acts on the magnetic sensor 47.

  On the other hand, as shown in FIG. 2, a plate-like magnetic shielding member 60 that shields magnetism is provided on the outer peripheral surface of the second holding member 49. Further, the right end portion of the second holding member 49 is accommodated in the torque sensor case 42. Then, the torque sensor case 42 is fastened to the right side surface of the case 30 by screws or the like (not shown), so that the first and second magnetic flux collecting rings 45 and 46 are relative to the case 30 at the positions in the drawing. It is held immovable.

  In the torque sensor 40, when a steering torque is input to the input shaft 20 and a relative rotational displacement is generated between the input shaft 20 and the lower shaft 21, as shown in FIGS. 5 (a) and 5 (b). The positional relationship between the cylindrical magnet 41 and the first and second yokes 43 and 44 changes, and the magnetism collected by the yokes 43 and 44 changes. In accordance with this change, the intensity of magnetism applied to the magnetic sensor 47 changes, and a voltage signal corresponding to the relative rotational displacement of each shaft 20, 21 is output from the magnetic sensor 47. As shown in FIG. 2, the output signal of the magnetic sensor 47 is output to the control device 15 via a wiring 42a provided on the right side surface of the torque sensor case 42. And the control apparatus 15 detects the relative rotational displacement of each shaft 20 and 21 based on the output of the magnetic sensor 47, and integrates, for example, the spring constant of the torsion bar 22 to the detected relative rotational displacement. For example, the steering torque is calculated.

  On the other hand, the rotation angle sensor 50 includes a box-shaped sensor body 51 that is housed in an opening formed on the left side surface of the case 30 and is disposed in the vicinity of the outer periphery of the left side surface of the torque sensor 40. The sensor main body 51 has a structure in which various components such as the detection gear 52 and the substrate 53 are accommodated. As shown in FIG. 6, the entire rotation angle sensor 50 is fixed to the case 30 by fastening the flange portion 51 b formed on the sensor main body 51 to the left side surface of the case 30 with a screw 33. Here, as shown in FIG. 2, the center portion of the detection gear 52 is supported by a shaft portion 51 a formed on the inner wall of the sensor body 51 so as to be rotatable about the axis n <b> 1 in the drawing. In addition, a part of the detection gear 52 is exposed to the outside from an opening formed on the torque sensor 40 side of the sensor body 51 and is extended close to the lower end of the second holding member 49, so that the first holding member The outer teeth 48a formed on the outer peripheral surface of the 48 press-fitting portions 48b are meshed. That is, the detection gear 52 rotates around the shaft portion 51 a based on the rotation of the first holding member 48. If the external teeth 48a are formed on the first holding member 48 in this way, the first holding member 48 can function as a gear, so that a separate gear with which the detection gear 52 is meshed can be provided. There is no need to attach to the first holding member 48 or the lower shaft 21. For this reason, it becomes possible to reduce the number of parts. Further, if the external teeth 48a are formed on the outer peripheral surface of the press-fit portion 48b of the first holding member 48, the axial directions of the shafts 20 and 21 are provided while the external teeth 48a are provided on the first holding member 48. The length of the first holding member 48 can be shortened as much as possible. For this reason, it is possible to reduce the size of the sensor device 14.

  On the other hand, a mounting table 52 a to which the first magnet 54 is fixed is provided at the center of the detection gear 52. The substrate 53 is mounted with a first magnetic sensor 55 as a rotation angle sensor magnetic detecting portion facing the first magnet 54, and the magnetism (bias magnetic field) formed by the first magnet 54 is mounted. ) Is given to the first magnetic sensor 55. The first magnetic sensor 55 is a so-called MR sensor that is configured by a magnetoresistive element that changes its resistance value according to the direction of magnetism by the magnetoresistive effect, and is formed by a first magnet 54. A voltage signal corresponding to the direction of magnetism is output.

  By the way, in the rotation angle sensor 50 having such a structure, when the magnetism generated from the first magnet 54 reaches the first and second magnetism collecting rings 45 and 46 of the torque sensor 40, this magnetism is applied to the magnetism of the torque sensor 40. It will be detected by the sensor 47. That is, magnetic interference occurs in the torque sensor 40. When such magnetic interference occurs, the sensing accuracy of the torque sensor 40 may be reduced.

  Therefore, in the present embodiment, as shown in FIG. 7, as the first magnet 54, two magnetic poles of N pole and S pole are provided in the upper layer and the lower layer, respectively, and the lower layer is opposed to the upper N pole. The S pole is a quadrupole magnet in which the lower N pole is disposed opposite to the upper S pole. Thereby, as indicated by an arrow in FIG. 7, the magnetic field lines B1 emitted upward from the N pole of the upper layer are taken into the S pole of the upper layer, and the magnetic field lines B2 emitted from the upper N pole to the left are It is taken into the south pole. The magnetic field lines B3 emitted downward from the lower N pole are taken into the lower S pole, and the magnetic lines B4 emitted from the lower N pole to the right are taken into the upper S pole. Accordingly, since the magnetism emitted from the first magnet 54 can be prevented from diffusing in directions other than the vertical direction, the magnetism emitted from the first magnet 54 is applied to the first and second magnetism collecting rings 45 and 46. Can be suppressed. Further, since the magnetic shielding member 60 is provided between the first magnet 54 and the first and second magnetism collecting rings 45 and 46, the magnetic shielding member 60 also emits from the first magnet 54. It is possible to suppress the generated magnetism from reaching the first and second magnetism collecting rings 45 and 46. As a result, the detection accuracy of the torque sensor 40 can be accurately maintained. In addition, since the magnetic field lines B <b> 1 emitted upward from the N pole on the upper layer of the first magnet 54 pass through the first magnetic sensor 55, magnetism can be accurately imparted to the first magnetic sensor 55.

  In the rotation angle sensor 50, as shown in FIG. 2, when the first holding member 48 rotates around the axis line m integrally with the lower shaft 21, the detection gear 52 and the first magnet 54 move along the axis line. The direction of magnetism applied to the first magnetic sensor 55 changes around n1. As a result, a voltage signal corresponding to the rotation angle of the detection gear 52 is output from the first magnetic sensor 55. The power supply to the first magnetic sensor 55 and the output signal of the first magnetic sensor 55 to the external device are performed via the wiring 51 c provided on the left side surface of the sensor main body 51.

  On the other hand, when the cross-sectional structure along the line AA in FIG. 2 is shown in FIG. 8, the sensor main body 51 is provided with a subordinate gear 56 that meshes with the detection gear 52 and rotates around the axis n2 in the drawing. It has been. In FIG. 8, the cross-sectional shape of the first holding member 48 is also shown for reference. For convenience, with respect to the external teeth of the detection gear 52, the dependent gear 56, and the first holding member 48, only the meshing portion is illustrated, the pitch circle is indicated by a one-dot chain line, and the tip circle is indicated by two points. Each is indicated by a chain line. As shown in FIG. 8, the dependent gear 56 has an outer diameter smaller than that of the detection gear 52 and has a different number of teeth from that of the detection gear 52. Also, a mounting table 56a is provided at the center of the dependent gear 56 in the same manner as the detection gear 52, and a second magnet 57 is fixed to the upper surface of the mounting table 56a. The second magnet 57 is also composed of a quadrupole magnet in the same manner as the first magnet 54 in order to prevent magnetic diffusion to the surroundings. Although not shown, the magnetic shielding member 60 illustrated in FIG. 2 is also disposed between the second magnet 57 and the torque sensor 40. On the other hand, a second magnetic sensor 58 is mounted on the substrate 53 shown in FIG. 2 so as to face the second magnet 57 as shown by a broken line in FIG. The magnetic field (bias magnetic field) is applied to the second magnetic sensor 58. Similarly to the first magnetic sensor 55, the second magnetic sensor 58 is also composed of an MR sensor. As a result, when the subordinate gear 56 rotates about the axis line n2 in the drawing as the detection gear 52 rotates, a voltage signal corresponding to the rotation angle of the subordinate gear 56 is output from the second magnetic sensor 58. Note that the power supply to the second magnetic sensor 58 and the acquisition of the external device of the output signal of the second magnetic sensor 58 are also performed via the wiring 51c shown in FIG. Further, in the external device, the respective rotation angles of the detection gear 52 and the subordinate gear 56 are detected based on the outputs of the first and second magnetic sensors 55 and 58, and a known calculation is performed from the detection results. The absolute rotation angle of the lower shaft 21, that is, the steering angle is calculated by the method.

  According to such a structure, as shown in FIG. 2, the sensor body 51 of the rotation angle sensor 50 is arranged in parallel with the torque sensor 40 in the radial direction of the shafts 20, 21. The installation space of the rotation angle sensor 50 in the axial direction can be reduced. For this reason, it is possible to reduce the size of the sensor device 14 in the axial direction of the shafts 20 and 21.

  Further, for example, when the rotation angle sensor 50 is not required according to the option setting of the electric power steering device, the entire rotation angle sensor 50 can be removed from the side surface of the case 30 only by removing the screw 33 shown in FIG. Easy to remove. For this reason, it becomes easy to make the electric power steering apparatus on the production line according to the option setting.

As described above, according to the sensor device of the present embodiment, the following effects can be obtained.
(1) The rotation angle sensor 50 is arranged close to the outer periphery of the torque sensor 40 in the radial direction of the shafts 20 and 21. Thereby, since the installation space of the rotation angle sensor 50 in the axial direction of each shaft 20 and 21 can be reduced, the sensor device can be downsized in the axial direction of each shaft 20 and 21. In addition, since the entire rotation angle sensor 50 can be easily removed from the side surface of the case 30, it is easy to make differently according to the presence or absence of the rotation angle sensor 50 in the production line of the electric power steering apparatus.

  (2) The rotation angle sensor 50 employs quadrupole magnets as the first and second magnets 54 and 57 for applying magnetism to the first and second magnetic sensors 55 and 58. Thereby, since magnetic interference in the torque sensor 40 can be suppressed, the sensing accuracy of the torque sensor 40 can be accurately maintained.

  (3) The magnetic shielding member 60 is provided between the torque sensor 40 and the first and second magnets 54 and 57. Thereby, since magnetic interference in the torque sensor 40 can be further suppressed, the sensing accuracy of the torque sensor 40 can be maintained more accurately.

  (4) The outer teeth 48a with which the detection gear 52 is meshed are formed on the outer peripheral surface of the press-fit portion 48b of the first holding member 48. This eliminates the need to attach a separate gear with which the detection gear 52 is engaged to the first holding member 48 or the lower shaft 21, thereby simplifying the structure. Moreover, since the length of the 1st holding member 48 in the axial direction of each shaft 20 and 21 can be shortened as much as possible while providing the external tooth 48a in the 1st holding member 48, size reduction of a sensor apparatus is possible. It becomes possible to plan.

  (5) The sensor device according to the present invention is applied to a sensor device mounted on an electric power steering device of a vehicle. Thereby, in the electric power steering device, the sensor device for detecting the steering angle and the steering torque can be downsized in the axial direction of the input shaft 20 and the lower shaft 21, in other words, in the axial direction of the steering shaft 2. Therefore, it is possible to reduce the size of the electric power steering device.

In addition, the said embodiment can also be implemented with the following forms which changed this suitably.
In the above embodiment, the external teeth 48a are formed on the outer peripheral surface of the press-fit portion 48b of the first holding member 48. However, depending on the shape of the first holding member 48, the external teeth May be formed. In short, it is sufficient that external teeth are formed on the outer peripheral surface of the first holding member 48.

  In the above embodiment, quadrupole magnets are used as the first and second magnets 54 and 57. For example, when the magnetic interference of the torque sensor 40 can be suppressed only by providing the magnetic shielding member 60. For example, various magnets may be used such as a dipole magnet as the first and second magnets 54 and 57.

  In the above embodiment, the magnetic shielding member 60 is provided between the first and second magnets 54 and 57 and the torque sensor 40. For example, a quadrupole magnet is used as the first and second magnets 54 and 57. If it is possible to suppress the magnetic interference of the torque sensor 40 only by using, the magnetic shielding member 60 can be omitted.

  In the above embodiment, the torque sensor 40 is a torque sensor that uses the magnetic sensor 47 configured around the Hall element. Instead, an appropriate torque sensor such as a twin resolver type torque sensor or a two-bobbin type torque sensor may be used. FIG. 9 shows an example of a twin resolver type torque sensor 70. In FIG. 9, elements having the same functions as those shown in FIG. 2 are denoted by the same reference numerals. As shown in FIG. 9, the torque sensor 70 includes a first resolver 71 that detects the rotation angle of the input shaft 20 and a second resolver 72 that detects the rotation angle of the lower shaft 21. Among these, the first resolver 71 includes an excitation coil 71 a attached to the outer peripheral surface of the input shaft 20, and a detection coil 71 b attached to the case 30 via a holding member 73. The first resolver 71 outputs a voltage signal corresponding to the rotation angle of the input shaft 20 by detecting the magnetism emitted from the excitation coil 71a by the detection coil 71b. The second resolver 72 includes an excitation coil 72 a attached to the outer peripheral surface of the lower shaft 21 and a detection coil 72 b attached to the case 30 via a holding member 73. The second resolver 72 outputs a voltage signal corresponding to the rotation angle of the lower shaft 21 by detecting the magnetism emitted from the excitation coil 72a by the detection coil 72b. The outputs of the first and second resolvers 71 and 72 are output to the control device 15 through the connector 32 provided on the right side surface of the case 30. On the other hand, a main gear 74 with which the detection gear 52 is engaged is attached to a portion of the outer periphery of the lower shaft 21 that is lower than the portion to which the excitation coil 72a is attached. Accordingly, when the main gear 74 rotates around the axis line m integrally with the lower shaft 21, the detection gear 52 rotates around the axis line n1. Thus, even when the twin resolver type torque sensor 70 is used, as shown in the drawing, the sensor body 51 of the rotation angle sensor 50 is replaced with a torque sensor in the radial direction of the input shaft 20 and the lower shaft 21. If it arrange | positions close to the outer periphery of 70, it is possible to acquire the effect similar to the said embodiment. Similar to the above embodiment, a magnetic shielding member may be provided between the torque sensor 70 and the first and second magnets 54 and 57.

  In the above embodiment, the rotation angle sensor 50 is a rotation angle sensor that detects the absolute angle of the lower shaft 21 based on the rotation angles of the detection gear 52 and the dependent gear 56. Instead, for example, a rotation sensor that includes only the detection gear 52 and detects the relative angle of the lower shaft 21 based on the rotation angle thereof may be used.

  In the above embodiment, the outer teeth 48a with which the detection gear 52 is meshed are formed on the outer peripheral surface of the first holding member 48. Instead, for example, the outer teeth are formed on the outer peripheral surface of the lower shaft 21. May be formed. Further, external teeth may be formed on the outer peripheral surface of the input shaft 20. In addition, when forming external teeth on the outer peripheral surface of the input shaft 20, for example, if the arrangement of the rotation angle sensor 50 illustrated in FIG. 2 is reversed in the vertical direction and the outer diameter of the detection gear 52 is increased, The detection gear 52 can be meshed with the external teeth formed on the input shaft 20. In this case, if the right portion of the detection gear 52 is disposed close to the upper end of the second holding member 49, the installation space for the rotation angle sensor 50 in the axial direction of the shafts 20 and 21 can be reduced. Is possible. If it is difficult to form external teeth on the first holding member 48, the input shaft 20, and the lower shaft 21, appropriate gears are separately attached to the outer periphery thereof as illustrated in FIG. May be.

The first and second magnetic sensors 55 and 58 are not limited to MR sensors, and may be any sensor that can detect the magnetic direction, such as a Hall IC.
-In above-mentioned embodiment, although the sensor apparatus concerning this invention was applied to the sensor apparatus mounted in the electric power steering apparatus of a vehicle, the torque provided to a rotating shaft and the rotation angle of a rotating shaft are detected. The present invention can be applied to an appropriate sensor device that can be used.

<Appendix>
Next, a technical idea that can be grasped from the above embodiment and its modifications will be additionally described.
(A) It has an electric motor that applies assist force to the steering shaft or rack shaft of the vehicle, and detects the steering angle and steering torque when steering the vehicle through a sensor device provided on the steering shaft. In the electric power steering apparatus in which a target torque is set based on a steering torque detected through the apparatus and a driving amount of the electric motor is controlled to generate the target torque, the steering shafts are mutually connected via a torsion bar. An electric power comprising a connected first rotating shaft and a second rotating shaft, wherein the sensor device according to any one of claims 1 to 5 is used as the sensor device. Steering device. The present invention is particularly effective when applied to an electric power steering apparatus as in the invention described in Appendix A. As a result, in the electric power steering device, the sensor device for detecting the steering angle and the steering torque can be downsized in the axial direction of the steering shaft, so that the electric power steering device can be downsized. Become.

  m: axis, B1 to B4 ... magnetic lines, n1, n2 ... axis, 1 ... steering wheel, 2 ... steering shaft, 3 ... column shaft, 4 ... intermediate shaft, 5 ... pinion shaft, 6 ... rack and pinion mechanism, 7 DESCRIPTION OF SYMBOLS ... Rack shaft, 8 ... Tie rod, 9 ... Steering wheel, 10 ... Electric power steering device, 11 ... Electric motor, 12 ... Gear mechanism, 13 ... Vehicle speed sensor, 14 ... Sensor device, 15 ... Control device, 20 ... Input shaft, DESCRIPTION OF SYMBOLS 21 ... Lower shaft, 22 ... Torsion bar, 23, 24 ... Connection pin, 30 ... Case, 31 ... Bearing, 32 ... Connector, 33 ... Screw, 40, 70 ... Torque sensor, 41 ... Cylindrical magnet, 42 ... For torque sensor Case, 42a ... Wiring, 43, 44 ... Yoke, 43a, 44a ... Ring portion, 43b, 44b ... Claw portion, 45 46 ... Magnetic collecting ring, 45a, 46a ... Magnetic collecting part, 47, 55, 58 ... Magnetic sensor, 48, 49 ... Holding member, 48a ... External teeth, 48b ... Press-fit part, 50 ... Rotation angle sensor, 51 ... Sensor body , 51a ... shaft portion, 51b ... flange portion, 51c ... wiring, 52 ... detection gear, 52a ... mounting table, 53 ... substrate, 54, 57 ... magnet, 56 ... subordinate gear, 56a ... mounting table, 60 ... magnetic shielding member 71, 72 ... resolver, 71a, 72a ... exciting coil, 71b, 72b ... detection coil, 73 ... holding member, 74 ... main gear.

Claims (5)

It is disposed along the first and second rotating shafts that are coaxially connected via the torsion bar, and when torque is applied to either one of the first and second rotating shafts, A torque sensor for detecting the torque by detecting a relative rotational displacement occurring in
A rotation angle sensor disposed close to the outer periphery of the torque sensor in the radial direction of the rotation shaft,
The rotation angle sensor is
A detection gear that rotates based on the rotation of one of the first and second rotating shafts;
A sensor body that is a part that detects a rotation angle of the detection gear,
A sensor device that detects a rotation angle of one of the first and second rotation shafts based on a rotation angle of the detection gear detected through the sensor body. The torque sensor includes a torque sensor magnetism detection section and a magnetism formation section that forms a first magnetism applied to the torque sensor magnetism detection section, and the first and second rotating shafts are relatively relative to each other. Detecting the relative rotational displacement of the first and second rotary shafts by detecting the change of the first magnetism caused by the cooperation of various rotational displacements through the magnetic sensor for the torque sensor. And
The detection gear is provided with a quadrupole magnet,
The sensor body has a magnetic sensor for a rotation angle sensor that is arranged to face the quadrupole magnet and detects a second magnetism formed by the quadrupole magnet,
The rotation angle sensor detects a change occurring in the second magnetism based on rotation of the detection gear through the rotation angle sensor magnetic detection unit, thereby rotating one of the first and second rotation shafts. The sensor device according to claim 1, which detects a corner. The sensor device according to claim 2, wherein a magnetic shielding member is provided between the torque sensor and the quadrupole magnet. The magnetic forming part is composed of a cylindrical magnet attached to the outer periphery of the first rotating shaft,
The torque sensor includes a yoke disposed so as to surround the cylindrical magnet, and a cylindrical holding member that holds the yoke and rotates integrally with the second rotation shaft. When the relative rotational displacement of the second rotating shaft occurs, the torque sensor magnetic detection unit detects a change in magnetism generated in the yoke based on the relative rotational displacement of the cylindrical magnet and the holding member. Detecting the relative rotational displacement of the first and second rotating shafts by detecting through
The sensor device according to claim 2, wherein outer teeth that engage with the detection gear are formed on an outer peripheral surface of the holding member. The holding member is integrally assembled to the second rotating shaft by press-fitting the second rotating shaft therein, and the external teeth are the second rotation of the holding member. The sensor device according to claim 4, wherein the sensor device is formed on an outer peripheral surface of a portion into which the shaft is press-fitted.

Images