JP2014065367A - Rotation angle/rotational torque detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotation angle/rotational torque detecting device that is used, for example, for detecting a rotation angle and rotational torque of mainly automobile steering and that can perform reliable and high-precision detection without errors.SOLUTION: Second magnets 14 mounted to a first detection gear 22 and a second detection gear 23 respectively are provided on a lateral side of an intermediate part of a first magnet body 5 and a second magnet body 6 that are substantially ring-shaped and arranged opposite to a first magnet 4, thereby the second magnets 14 rotating by being mounted to the first detection gear 22 and the second detection gear 23 are placed in a position at nearly equal distances from the first magnet body 5 and the second magnet body 6 on the lateral side of the intermediate part of the first magnet body 5 and the second magnet body 6. As a result, magnetic flux fluctuation of the first magnet body 5 and the second magnet body 6 due to the second magnet 14 is divided into almost equal portions, so that rotational torque can be detected without errors and the rotation angle/rotational torque detecting device which can perform reliable high-precision detection of the rotation angle and the rotational torque can be obtained.

Description

  The present invention relates to a rotation angle / torque detection device mainly used for detection of a rotation angle and a rotation torque of a steering of an automobile.

  In recent years, with the advancement of advanced functions of automobiles, various rotational torque detectors and rotational angle detectors are used to detect the rotational torque and rotational angle of the steering and perform various controls of the vehicle such as a power steering device and a brake device. Things are increasing.

  Such a conventional rotation angle / torque detection device will be described with reference to FIGS. 4 and 5. FIG.

  4 is a cross-sectional view of a conventional rotation angle / torque detection device, and FIG. 5 is a partial perspective view. In FIG. 4, reference numeral 1 denotes a substantially cylindrical first rotating body that rotates in conjunction with steering. A substantially cylindrical second rotating body 3 disposed below the first rotating body 1 is a substantially columnar connecting body, with the first rotating body 1 at the upper end of the connecting body 3 and the second rotating body at the lower end. The rotating bodies 2 are fixed to each other.

  Reference numeral 4 denotes a substantially cylindrical first magnet, in which a plurality of N poles and S poles having different magnetic poles are adjacent to each other vertically and horizontally, arranged in the circumferential direction, and the first magnet 4 is It is fixed to the outer periphery of the second rotating body 2.

  Reference numeral 5 denotes a substantially ring-shaped first magnetic body, and 6 denotes a second magnetic body. The first magnetic body 5 and the second magnetic body 6 face the outer periphery of the first magnet 4 and Are arranged one above the other with a gap in between.

  Furthermore, 7 is a substantially rectangular third magnetic body, and a plurality of third magnetic bodies 7 are radially arranged at predetermined angular intervals by insert molding, press fitting, or the like in the first rotating body 1. The first magnet 4 is disposed between the first magnetic body 5 and the second magnetic body 6.

  Reference numeral 8 denotes a wiring board on which a plurality of wiring patterns (not shown) are formed on the upper and lower surfaces. The first magnetic body 5 and the second magnetic body 6 are opposed to the first magnet 4 on the upper surface. A first magnetic detection element 9 such as a Hall element is mounted and mounted between the two, and a control means 10 connected to the first magnetic detection element 9 is formed by an electronic component such as a microcomputer. Thus, a rotational torque detector is configured.

  Reference numeral 11 denotes a rotating gear formed below the outer periphery of the second rotating body 2, reference numeral 12 denotes a first detecting gear, reference numeral 13 denotes a second detecting gear, which are formed to have different numbers of teeth and rotate. The first detection gear 12 and the second detection gear 13 are meshed with the gear 11.

  Further, a second magnet 14 is mounted on the center of the first detection gear 12 and the second detection gear 13 by a holding member, insert molding, or the like, and faces the second magnet 14. A plurality of second magnetic detection elements 15 such as AMR (anisotropic magnetoresistance) elements are mounted and mounted on the lower surface of the wiring board 8.

  The rotation gear 11, the first detection gear 12, the second detection gear 13, the second magnet 14, and the second magnetic detection element 15 form a rotation angle detector, and the second The magnetic detection element 15 is connected to the control means 10 to constitute a rotation angle / torque detection device.

  The rotation angle / torque detection device configured in this way is mounted on the first rotating body 1 or the second rotating body 2 with the steering shaft mounted below the steering wheel of the automobile, and the control means. 10 is connected to an electronic circuit (not shown) of the automobile body via a connector, a lead wire (not shown) or the like.

  In the above configuration, when the steering wheel is rotated, the first rotating body 1 is rotated along with the rotation of the steering wheel, and after the connecting body 3 is twisted, the second rotating body 2 is slightly delayed from the first rotating body 1. At this time, for example, since the rotational torque is small when the vehicle is traveling, there is little delay in the rotation of the second rotating body 2 with respect to the first rotating body 1, and the rotational torque is large when the vehicle is stopped. The delay in rotation of the body 2 increases.

  Then, as the first rotating body 1 rotates, the third magnetic body 7 fixed to the first rotating body 1 rotates, and the first magnet 4 fixed to the second rotating body 2 a little later than this. And the first magnetic detection element 9 passes through the first magnetic body 5, the second magnetic body 6, and the third magnetic body 7, and the N-pole and S-pole magnets of the first magnet 4. Is detected and input to the control means 10.

  At this time, the magnetism detected by the first magnetism detecting element 9 is the second rotation in which the first magnet 4 is fixed to the first rotating body 1 to which the third magnetic body 7 is fixed. When the rotation delay of the body 2 is small, the magnetism is weak, and when the rotation delay is large, the magnetism is strong.

  Then, from the strength of the magnetism of the first magnetic detecting element 9 detected through the first magnetic body 5 and the second magnetic body 6, the control means 10 is used for the first rotating body 1, that is, the steering shaft. The rotational torque is calculated and output to the electronic circuit of the vehicle body.

  Further, as the second rotating body 2 rotates, the rotating gear 11 formed below the outer periphery rotates, so that the first detecting gear 12 and the second detecting gear 13 meshed with the rotating gear 11 are respectively It rotates in conjunction.

  In addition, as the first detection gear 12 and the second detection gear 13 rotate, the plurality of second magnets 14 mounted in the center of the first detection gear 12 and the second detection gear 13 also rotate, and this changing magnetism is transferred to the plurality of second magnets. A sine wave, cosine wave, or substantially sawtooth angle detection signal that is detected by the magnetic detection element 15 and repeatedly increases and decreases is input to the control means 10.

  At this time, since the first detection gear 12 and the second detection gear 13 have different numbers of teeth, the angle detection signals output from the plurality of second magnetic detection elements 15 are the inclinations of the data waveforms. The angle and shape are different and there is a phase difference that is input to the control means 10.

  Then, from the angle detection signals from the first detection gear 12 and the second detection gear 13 and the number of teeth of each gear, the control means 10 performs a predetermined calculation to rotate the rotating gear 11, that is, the steering shaft. The angle is detected and output to the electronic circuit of the automobile body. The electronic circuit calculates data such as the rotational angle and the rotational torque from the control means 10 described above, and the vehicle such as the power steering device or the brake device is calculated. Various controls are performed.

  That is, according to the rotation angle and torque output from the control means 10, the control of the effectiveness of the brake device in accordance with the rotation operation angle of the steering wheel, the control of the force for rotating the steering wheel, etc. Was configured to be performed by.

  As prior art document information related to the invention of this application, for example, Patent Document 1 is known.

JP 2012-2519 A

  However, in the conventional rotation angle / torque detection device, the control means 10 rotates from the strength of the magnetism detected by the first magnetic detection element 9 via the first magnetic body 5 and the second magnetic body 6. Although it is formed so as to calculate torque, a second magnet 14 is mounted in the vicinity of the second magnetic body 6 and mounted in the center of the first detection gear 12 and the second detection gear 13 and rotates. Therefore, the magnetic flux of the second magnetic body 6 close to the second magnet 14 may fluctuate due to this magnetism, and an error may occur in the magnetism detected by the first magnetic detection element 9. was there.

  The present invention solves such a conventional problem, and an object of the present invention is to provide a rotation angle / torque detection device capable of detecting a rotation angle and a rotation torque with high accuracy and accuracy without error. .

  In order to achieve the above object, the present invention relates to a second magnet mounted on a detection gear, which includes a first ring-shaped magnetic body and a second magnetic body that are arranged opposite to the first magnet. The rotation angle / torque detection device is provided on the side of the middle part, and the second magnet that is mounted on the detection gear and rotates is located on the side of the middle part of the first magnetic body and the second magnetic body. Since the first magnetic body and the second magnetic body are disposed at substantially equal distances, the fluctuation of the magnetic flux between the first magnetic body and the second magnetic body by the second magnet is substantially equally divided. Thus, the rotation torque can be detected without error, and the rotation angle / torque detection device capable of detecting the rotation angle and the rotation torque with high accuracy and reliability can be obtained.

  As described above, according to the present invention, there is an advantageous effect that it is possible to realize a rotation angle / torque detection device that can detect a rotation angle and a rotation torque with high accuracy and reliability.

Sectional drawing of the rotation angle and torque detection apparatus by one embodiment of this invention Exploded perspective view Partial perspective view Sectional view of a conventional rotation angle / torque detection device Partial perspective view

  Hereinafter, embodiments of the present invention will be described with reference to FIGS.

  In addition, the same code | symbol is attached | subjected to the part of the structure same as the structure demonstrated in the term of background art, and detailed description is simplified.

(Embodiment)
FIG. 1 is a cross-sectional view of a rotation angle / torque detection device according to an embodiment of the present invention, FIG. 2 is an exploded perspective view thereof, and FIG. 3 is a partial perspective view thereof. A first rotating body made of an insulating resin such as polybutylene terephthalate which rotates in a substantially cylindrical shape, 2 is a substantially cylindrical second rotating body disposed below the first rotating body 1, 3 is a torsion bar, etc. The first rotating body 1 is fixed to the upper end of the connecting body 3 and the second rotating body 2 is fixed to the lower end thereof.

  Reference numeral 4 denotes a substantially cylindrical first magnet made of ferrite, Nd-Fe-B alloy, or the like. A plurality of N poles and S poles having different magnetic poles are vertically and horizontally arranged adjacently and arranged in the circumferential direction. At the same time, the first magnet 4 is fixed to the outer periphery of the second rotating body 2.

  In addition, 5 is a substantially ring-shaped first magnetic body such as permalloy, iron, Ni—Fe alloy, and the like, 6 is a second magnetic body, and the first magnetic body 5 and the second magnetic body 6 are the first. The magnet 4 is opposed to the outer periphery of the magnet 4 so as to be vertically stacked with a predetermined gap.

  Further, reference numeral 7 denotes a third rectangular magnetic body such as permalloy, iron, or Ni—Fe alloy, and the plurality of third magnetic bodies 7 are predetermined in the first rotating body 1 by insert molding, press fitting, or the like. Are arranged radially between the first magnet 4 and the first magnetic body 5 and the second magnetic body 6.

  8 is a wiring board such as paper phenol or glass epoxy, and a plurality of wiring patterns (not shown) are formed on the upper and lower surfaces by copper foil or the like, and the lower surface is opposed to the first magnet 4, A plurality of first magnetic detection elements 9 such as Hall elements and GMR elements, which are disposed between the first magnetic body 5 and the second magnetic body 6, are mounted and mounted, and electronic components such as a microcomputer are used. The control means 10 connected to the plurality of first magnetic detection elements 9 is formed to constitute a rotational torque detector.

  Reference numeral 11 denotes a rotating gear formed below the outer periphery of the second rotating body 2, reference numeral 22 denotes a first detection gear made of insulating resin, and reference numeral 23 denotes a second detection gear. The second detection gear 23 is provided with substantially cylindrical holding portions 22A and 23A protruding upward, and the first detection gear 22 and the second detection gear 23 are meshed with the rotary gear 11, respectively.

  In addition, the diameter and the number of teeth of these gears are the largest in the rotating gear 11, and are decreasing in the order of the first detecting gear 22 and the second detecting gear 23. For example, the number of teeth of the rotating gear 11 is 48, The number of teeth of the first detection gear 22 is 32, and the number of teeth of the second detection gear 23 is 28.

  In addition, second magnets 14 such as ferrite and Nd-Fe-B alloy are respectively held in the holding portions 22A and 23A of the first detection gear 22 and the second detection gear 23 at the center of the upper surface thereof. The first magnetic body 5 and the second magnetic body 5 are located on the side of the intermediate portion of the gap between the lower end of the first magnetic body 5 and the upper end of the second magnetic body 6. It arrange | positions so that it may become a substantially equidistant position from the 2nd magnetic body 6. FIG.

  Further, a plurality of second magnetic sensing elements 15 such as AMR (anisotropic magnetoresistive) elements are mounted and mounted on the lower surface of the wiring board 8 facing the plurality of second magnets 14. The first detection gear 22, the second detection gear 23, the second magnet 14, and the second magnetic detection element 15 form a rotation angle detection unit and control the plurality of second magnetic detection elements 15. Connected to the means 10, a rotation angle / torque detection device is configured.

  The rotation angle / torque detection device configured in this way is mounted on the first rotating body 1 or the second rotating body 2 with the steering shaft mounted below the steering wheel of the automobile, and the control means. 10 is connected to an electronic circuit (not shown) of the automobile body via a connector, a lead wire (not shown) or the like.

  In the above configuration, when the steering wheel is rotated, the first rotating body 1 is rotated along with the rotation of the steering wheel, and after the connecting body 3 is twisted, the second rotating body 2 is slightly delayed from the first rotating body 1. At this time, for example, since the rotational torque is small when the vehicle is traveling, there is little delay in the rotation of the second rotating body 2 with respect to the first rotating body 1, and the rotational torque is large when the vehicle is stopped. The delay in rotation of the body 2 increases.

  Then, as the first rotating body 1 rotates, the third magnetic body 7 fixed to the first rotating body 1 rotates, and the first magnet 4 fixed to the second rotating body 2 a little later than this. And the plurality of first magnetic detection elements 9 pass through the first magnetic body 5, the second magnetic body 6, and the third magnetic body 7, and the N pole and the S pole of the first magnet 4. Is detected, and this is input to the control means 10.

  That is, when the steering wheel is not rotated and is in a neutral position and the vehicle is in a straight traveling state, a plurality of elements arranged between the first magnet 4 and the first magnetic body 5 and the second magnetic body 6 are arranged. Since the center of the third magnetic body 7 is at the center of the N and S poles adjacent to each other of the first magnet 4, the magnetic forces from these N poles to the S poles are in balance.

  Accordingly, no magnetic flux is generated between the first magnetic body 5 and the second magnetic body 6 outside the plurality of third magnetic bodies 7, and thus the plurality of first magnetic bodies disposed between them. The magnetism detected by the magnetism detecting element 9 is zero.

  On the other hand, the steering wheel is rotated right or left, the first magnet 4 or the third magnetic body 7 is rotated, and the center of the third magnetic body 7 is shifted from the first magnet 4. In this state, the first magnet 4 generates a magnetic flux that forms a closed magnetic path from the N pole to the S pole in the third magnetic body 7.

  At the same time, a magnetic flux from the N pole to the S pole is also generated by the first magnet 4 in the first magnetic body 5 and the second magnetic body 6, so that this magnetism is used as a plurality of first magnetic detection elements. 9, a predetermined voltage waveform corresponding to the strength of the magnetism is output to the control means 10 as a torque detection signal.

  At this time, the rotation delay of the second rotating body 2 relative to the first rotating body 1 is about 1 degree as an angle when the rotational torque is small, and around 4 degrees when the rotational torque is large. At the same time, the magnetism detected by the plurality of first magnetism detecting elements 9 is the second magnet with the first magnet 4 fixed to the first rotor 1 to which the third magnetic body 7 is fixed. When the rotation delay of the rotating body 2 is small, the magnetism is weak, and when the rotation delay is large, the magnetism is strong.

  Then, the control means 10 performs the first rotation from the strength of the magnetism of the first magnetic detection element 9 detected through the first magnetic body 5, the second magnetic body 6, and the third magnetic body 7. The rotational torque of the body 1, that is, the steering shaft is calculated and output to the electronic circuit of the vehicle body.

  Further, as the second rotating body 2 rotates, the rotating gear 11 formed below the outer periphery rotates, so that the first detecting gear 22 and the second detecting gear 23 meshed with the rotating gear 11 respectively. It rotates in conjunction.

  As the first detection gear 22 and the second detection gear 23 rotate, the plurality of second magnets 14 mounted in the center of the first detection gear 22 and the second detection gear 23 also rotate to change the direction of magnetism. A plurality of second magnetic detection elements 15 detect the direction of magnetism of the second magnet 14, and a sine wave, cosine wave, or substantially sawtooth angle detection signal that repeatedly increases and decreases is input to the control means 10.

  At this time, since the first detection gear 22 and the second detection gear 23 have different numbers of teeth, the angle detection signal output from the plurality of second magnetic detection elements 15 is the inclination angle of the data waveform. And the shape is different and the phase difference is input to the control means 10.

  Then, the control means 10 performs a predetermined calculation from the two different angle detection signals from the first detection gear 22 and the second detection gear 23 and the number of teeth of each spur gear portion, and the rotation gear 11, That is, the rotation angle of the steering is detected, and this rotation angle signal is output to the electronic circuit of the automobile body. The electronic circuit calculates the rotation angle signal and the data such as the rotation torque signal from the control means 10 described above. Various controls of the vehicle such as a power steering device and a brake device are performed.

  In other words, the electronic circuit adjusts to the running or stopped state of the vehicle. For example, when the vehicle is running and the rotational torque of the steering is small, the power steering device is loosened and the steering wheel is rotated with a somewhat heavy force. Thus, when the vehicle is stopped and the rotational torque of the steering is large, the power steering device is greatly effective and control is performed so that the steering wheel can be rotated even with a light force.

  Alternatively, when the steering is greatly rotated by the rotation angle signal from the control means 10, the effect of the brake device is intermittently activated, and when the steering is rotated slightly, the brake device is continuously activated. The brake device is controlled in accordance with the rotation of the steering wheel.

  At this time, in the present invention, the second magnet 14 mounted on the first detection gear 22 and the second detection gear 23 is connected to the first magnetic body 5 facing the first magnet 4 and the second magnet 14. Since the first magnetic body 5 and the second magnetic body 6 are provided at the side of the middle part of the second magnetic body 6 and are disposed at substantially equal distances, the first magnet by the second magnet 14 is used. Fluctuations in the magnetic flux of the body 5 and the second magnetic body 6 are almost equally divided so that no error occurs in the magnetism detected by the first magnetic detection element 9.

  That is, the first detection gear 22 and the second detection gear 23 are provided with substantially cylindrical holding portions 22A and 23A protruding upward, and a plurality of second magnets 14 are respectively attached to the center of the upper surface. By forming these second magnets 14 so as to be positioned on the side of the middle portion of the gap between the lower end of the first magnetic body 5 and the upper end of the second magnetic body 6 that are stacked one above the other, Only one of the body 5 and the second magnetic body 6 is configured to be affected by the magnetism of the second magnet 14 and prevent the magnetic flux from fluctuating.

  Further, a plurality of first magnetic detection elements 9 are provided between the first magnetic body 5 and the second magnetic body 6, and the magnetism of the first magnet 4 is detected by the plurality of first magnetic detection elements 9. As a result, even if one of the first magnetic detection elements 9 is damaged or malfunctioned, the control means 10 can detect these malfunctions.

  In the above description, the third magnetic body 7 is fixed to the first rotating body 1, and the first magnet 4 is fixed to the second rotating body 2, and the second rotating body 2 rotates below the outer periphery. The configuration in which the gear 11 is provided and the first detection gear 22 and the second detection gear 23 are engaged with each other has been described. However, the first magnet 4 is connected to the first rotary body 1 and the second rotary body is set. 2 and the configuration in which the third magnetic body 7 is fixed, or the configuration in which the rotation gear 11 is provided in the first rotation body 1 and the first detection gear 22 and the second detection gear 23 are engaged with each other. Implementation of the present invention is possible.

  Further, a configuration in which the first detection gear 22 is meshed with the rotary gear 11 and the second detection gear 23 is meshed with the first detection gear 22, or the first detection gear 22 or the second gear is coupled to the rotary gear 11. Only one of the two detection gears 23 may be engaged.

  As described above, according to the present embodiment, the second magnet 14 mounted on the first detection gear 22 and the second detection gear 23 is arranged in a substantially ring shape arranged to face the first magnet 4. By providing the first magnetic body 5 and the second magnetic body 6 at the side of the intermediate portion, the second magnet 14 mounted on the first detection gear 22 and the second detection gear 23 and rotating is provided. Since the first magnetic body 5 and the second magnetic body 6 are disposed at an approximately equal distance from the first magnetic body 5 and the second magnetic body 6 on the side of the intermediate portion, the second magnet 14, the fluctuation of the magnetic flux of the first magnetic body 5 and the second magnetic body 6 is almost equally divided, the rotational torque can be detected without error, and the rotational angle and the rotational torque that can detect the rotational torque with high accuracy and reliability can be detected. -A torque detection device can be obtained.

  The rotation angle / torque detection device according to the present invention has an advantageous effect that there is no error and that it is possible to obtain a highly accurate and reliable detection of the rotation angle and rotation torque. This is useful for detecting the rotation angle and torque.

DESCRIPTION OF SYMBOLS 1 1st rotary body 2 2nd rotary body 3 Connection body 4 1st magnet 5 1st magnetic body 6 2nd magnetic body 7 3rd magnetic body 8 Wiring board 9 1st magnetic detection element 10 Control Means 11 Rotating gear 14 Second magnet 15 Second magnetic detection element 22 First detection gear 22A, 23A Holding portion 23 Second detection gear

Claims (1)

A first rotating body that rotates in conjunction with the steering, a second rotating body that is fixed to the first rotating body via a coupling body, and the first rotating body or the second rotating body. Between the first and second magnetic bodies, the substantially cylindrical first magnet, the substantially ring-shaped first and second magnetic bodies disposed opposite to the first magnet, and the first and second magnetic bodies. A first magnetic detection element disposed; a rotary gear formed on the first rotary body or the second rotary body; a detection gear meshed with the rotary gear; and a first gear mounted on the detection gear. Two magnets, a second magnetism detecting element for detecting the magnetism of the second magnet, and the control means connected to the first magnetism detecting element and the second magnetism detecting element. A rotation angle / torque detection device in which a magnet is provided on the side of an intermediate portion between the first magnetic body and the second magnetic body.

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