JP2009063316A - Rotation angle detecting device and shifting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotation angle detecting device which enables widening of the range of detection of a rotation angle wherein the angle can be detected accurately. <P>SOLUTION: The rotation angle detecting devices 30a and 30b have each a magnet 35 which has four magnetic poles integrally rotating with a rotating shaft, Hall elements 33 and 34, which are disposed opposite to the magnet 35 in the radial direction and detect the change in a magnetic flux density accompanying the rotation of the rotating shaft, and a tubular yoke 32 which is provided outside the Hall elements 33 and 34. The magnet 35 is given magnetic field orientation, in a direction opposite to that of the Hall elements 33 and 34, in a state where the boundary lines of the magnetic poles are disposed opposite to the Hall elements 33 and 34, while the magnet is magnetized along the direction of the magnetic field orientation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rotation angle detection device and a shift device.

  2. Description of the Related Art Conventionally, there is a so-called by-wire type shift device that detects a switching operation of a shift lever or the like as an electric signal and electronically switches a connection state of a vehicle transmission based on the detection signal. For such a shift device, for example, a rotation angle detection device as shown in Patent Document 1 is used to detect the rotation angle of the rotation shaft of the shift lever, and the operation position of the shift lever is detected based on this detection signal. It is possible to do.

This rotation angle detection device includes a magnet that rotates integrally with a rotation shaft, a Hall element that is arranged at a fixed interval from the circumference of the magnet, and a magnet and a hall that are concentrically with the rotation shaft outside the magnet and the Hall element. And a ring material made of a magnetic material provided so as to surround the element. When the magnet rotates with the rotation of the rotating shaft, the Hall element outputs a sinusoidal detection signal (output voltage) S2 corresponding to the change in magnetic flux density, as shown by a two-dot chain line in FIG. The control unit of the shift device detects the rotation angle of the rotation shaft based on the detection signal output from the rotation angle detection device. At this time, in order to detect the rotation angle with high accuracy, as shown in FIG. 6, in the detection signal S2 output from the Hall element, a region that can be regarded as a linear output in the vicinity where the output value is “0” (the detection signal S2 is This is performed using a linearly changing rotation angle region K2. Further, by drawing the magnetic field lines generated by the magnets into the ring material, dispersion of the magnetic field lines is suppressed, and the detection accuracy of the rotation angle is improved. The control unit of the shift device discriminates the operation position of the shift lever based on the rotation angle of the rotation shaft by the operation of the shift lever, and a switching signal for switching the connection state of the transmission to the connection state corresponding to the operation position. Is output.
JP 2003-262537 A

  However, in the conventional rotation angle detection device, as described above, when the magnet rotates with the rotation of the rotation shaft, the Hall element outputs a sinusoidal detection signal corresponding to the change in magnetic flux density passing through the Hall element. To do. In this sinusoidal detection signal, a region that can be regarded as a linear output is narrow. Accordingly, the detection range of the rotation angle that can be accurately detected is narrowed. Accordingly, when this rotation angle detection device is used in a shift device, the rotation angle of the rotation shaft corresponding to each operation position of the shift lever is reduced. The range is also narrowed. For this reason, for example, when an assembly error or the like occurs in the mechanical part of the rotation angle detection device and the positional relationship between the Hall element and the magnet varies, the operation position of the shift lever may be detected erroneously. Concerned.

  The present invention has been made in view of such conventional circumstances, and an object thereof is to provide a rotation angle detection device and a shift device capable of widening a detection range of a rotation angle that can be accurately detected. There is to do.

  The invention according to claim 1 is a magnet having a four-pole magnetic pole that rotates integrally with the rotating shaft, and is disposed opposite to the outer surface of the magnet and detects a change in magnetic flux density accompanying the rotation of the rotating shaft, A rotation angle detection device comprising: a magnetic detection element that outputs a sinusoidal detection signal; and a cylindrical yoke provided outside the magnetic detection element so as to surround the magnet and the magnetic detection element. The magnet is magnetically oriented in a direction perpendicular to the facing direction of the magnetic detection element when the boundary of one of the magnetic poles is arranged to face the magnetic detection element, and in the direction of the magnetic field orientation. The gist of the present invention is that it is an anisotropic magnet magnetized along.

  According to the present invention, since the magnet is magnetically oriented in a direction orthogonal to the facing direction of the magnetic detection element when the boundary between the magnetic poles is arranged to face the magnetic detection element, the magnetic detection element It becomes easy to be magnetized in the direction orthogonal to the facing direction. For this reason, when magnetized along the direction of the magnetic field orientation, the magnetic force in the direction perpendicular to the facing direction of the magnetic detection element in the magnet becomes stronger than the magnetic force in the facing direction of the magnetic detection element. As a result, the magnetic flux density on the boundary side of the magnetic pole arranged opposite to the magnetic detection element is lower than the magnetic flux density on the boundary side of the magnetic pole not arranged opposite to the magnetic detection element, and the magnetic flux density is highest in the circumferential direction of the magnet. The position is a position away from the boundary of the magnetic pole facing the magnetic detection element. Therefore, in the sinusoidal detection signal output from the magnetic detection element, the range of the rotation angle corresponding to the region that can be regarded as a linear output near the boundary of the magnetic pole arranged opposite to the magnetic detection element is widened, and the detection is performed with high accuracy. The detection range of the rotation angle that can be made can be widened. In addition, by providing a yoke so as to surround the magnet and the magnetic detection element outside the magnetic detection element, it is preferable to prevent the magnetic flux from leaking outside the yoke, so that the rotation angle can be detected more accurately. Can do.

The gist of the invention described in claim 2 is that it further includes another magnetic detection element disposed opposite to the magnetic detection element with the magnet interposed therebetween.
According to the present invention, the distribution of the magnetic flux density around the quadrupole magnet changes at a period of 180 deg. Therefore, the pair of magnetic detection elements arranged opposite to each other with the magnet interposed therebetween are substantially the same as the magnet rotates. A detection signal is output. For this reason, it becomes possible to measure a rotation angle by a double system based on the detection signal output from a pair of magnetic detection elements, and it is possible to improve the reliability of the rotation angle detection device.

  The invention according to claim 3 includes a shift lever that is rotated along a shift gate, and a rotation angle detection device that detects a rotation angle of the shift lever, and is based on a detection result of the rotation angle detection device. A shift device that switches a connection state of a transmission of a vehicle, wherein the rotation angle detection device is disposed opposite to a magnet having a four-pole magnetic pole that rotates integrally with a rotation shaft of the shift lever, and an outer surface of the magnet. And detecting a change in the magnetic flux density accompanying the rotation of the rotating shaft and outputting a sinusoidal detection signal, and enclosing the magnet and the magnetic detection element outside the magnetic detection element. A rotation angle detection device comprising a cylindrical yoke provided, wherein the magnet is paired with the magnetic detection element when a boundary of one magnetic pole thereof is disposed opposite to the magnetic detection element. With magnetic field orientation is performed in the direction perpendicular to the direction, and its gist that along the direction of the magnetic field orientation is magnetized anisotropic magnet.

  According to the present invention, since the magnet is magnetically oriented in a direction orthogonal to the facing direction of the magnetic detection element when the boundary between the magnetic poles is arranged to face the magnetic detection element, the magnetic detection element It becomes easy to be magnetized in the direction orthogonal to the facing direction. For this reason, in the magnet magnetized along the direction of the magnetic field orientation, the magnetic force in the direction orthogonal to the direction facing the magnetic detection element is stronger than the magnetic force in the direction facing the magnetic detection element. As a result, the magnetic flux density on the boundary side of the magnetic pole arranged opposite to the magnetic detection element is lower than the magnetic flux density on the boundary side of the magnetic pole not arranged opposite to the magnetic detection element, and the magnetic flux density is highest in the circumferential direction of the magnet. The position is a position away from the boundary of the magnetic pole facing the magnetic detection element. Therefore, in the sinusoidal detection signal output from the magnetic detection element, the range of the rotation angle corresponding to the region that can be regarded as a linear output near the boundary of the magnetic pole arranged opposite to the magnetic detection element is widened, and the detection is performed with high accuracy. The detection range of the rotation angle that can be made can be widened. As a result, it is possible to set a wide range of the rotation angle corresponding to each operation position of the shift lever, and it is preferable to prevent the operation position of the shift lever from being erroneously detected by the rotation angle detection device. be able to. Further, by providing the yoke outside the magnetic detection element, it is possible to suitably prevent the magnetic flux from leaking outside the yoke, so that the rotation angle can be detected with higher accuracy.

The gist of the invention described in claim 4 is that it further comprises another magnetic detection element disposed opposite to the magnetic detection element with the magnet interposed therebetween.
According to the present invention, the distribution of the magnetic flux density around the quadrupole magnet changes at a period of 180 deg. Therefore, the pair of magnetic detection elements arranged opposite to each other with the magnet interposed therebetween are substantially the same as the magnet rotates. A detection signal is output. For this reason, it becomes possible to measure a rotation angle by a double system based on the detection signal output from a pair of magnetic detection elements, and it is possible to improve the reliability of the rotation angle detection device. Therefore, the reliability of the shift device is also improved.

  The invention according to claim 5 is provided with return means for urging the shift lever, which is rotated from the reference position set along the shift gate to the operation position, to the reference position side, and the magnet includes: The gist is that the boundary of the magnetic pole is disposed opposite to the magnetic detection element in a state where the shift lever is at the reference position.

  According to the present invention, the disturbance magnetic field (disturbance magnetism) around the rotation angle detection device enters the yoke provided outside the magnetic detection element, and acts on the magnet while avoiding the boundary of the magnetic pole having a relatively low magnetic flux density. . For this reason, the influence of the disturbance magnetic field which acts on a magnetic detection element can be suppressed in the state where the magnetic flux density which passes through the magnetic detection element arranged facing the magnetic pole boundary of a magnet is comparatively low. Further, after the shift lever is rotated from the reference position to the operation position against the biasing force of the return means, when the operation force on the shift lever is released, the shift lever returns to the reference position by the biasing force of the return means. . For this reason, in a state where the shift lever is not operated, the magnet is disposed so that the boundary of the magnetic pole faces the magnetic detection element. That is, the influence of the disturbance magnetic field can be suppressed in a state where the shift lever is not operated, in other words, in a state where the magnetic flux density passing through the magnetic detection element is relatively low. For this reason, it is possible to prevent the operation position of the shift lever from being erroneously detected due to fluctuations in the detection signal output from the magnetic detection element due to the disturbance magnetic field, and to improve the reliability of the shift device. Can do.

  ADVANTAGE OF THE INVENTION According to this invention, the rotation angle detection apparatus and shift apparatus which can widen the detection range of the rotation angle which can be detected accurately can be provided.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
As shown to Fig.1 (a), the shift lever 2a of the shift apparatus 2 protrudes and is provided in the approximate center part of the instrument panel 1 in a vehicle interior. As shown in FIG. 1B, the shift device 2 is connected to a transmission 3 of the vehicle. The shift device 2 outputs a switching signal for switching the connection state of the transmission 3 based on a switching operation of the shift lever 2a by a vehicle occupant.

  As shown in FIG. 2A, a multi-axis structure 10 is provided at the base end portion of the shift lever 2a, and the multi-axis structure 10 is covered with a box-shaped housing (not shown). ing. The first structure 11 constituting the multi-axis structure 10 is supported by the housing so as to be rotatable about a first shaft 12 as a rotation shaft. A spring (torsion coil spring) 13 is provided on the outer periphery of the first shaft 12 as a return means. A proximal end portion 13 a of the spring 13 is fixed to the housing, and a distal end portion 13 b is fixed to the first structure 11. A protrusion 11 a extending in the direction along the first shaft 12 is formed at the center of the upper surface of the first structure 11. An insertion hole 11b extending in a direction orthogonal to the first shaft 12 is formed in the ridge 11a.

  The ridge 11 a is accommodated in a groove 14 a of the second structure 14 provided on the top of the first structure 11. The second structure 14 constitutes the multiaxial structure 10 together with the first structure 11. A through hole 14b extending in a direction perpendicular to the groove 14a is formed in a portion (lower part) corresponding to the groove 14a in the second structure 14. And the 2nd structure 14 inserts the 2nd axis | shaft 15 as a rotating shaft into the said through-hole 14b and the insertion hole 11b in the state which accommodated the said protrusion 11a in the groove part 14a, and thereby the 1st structure 11 is connected to the second shaft 15 so as to be rotatable. The second shaft 15 is connected to the second structure 14 so as to be integrally rotatable, while being inserted into the first structure 11 (more precisely, the protrusion 11a) so as to be relatively rotatable. Yes. On the outer periphery of the second shaft 15, a spring (torsion coil spring) 16 is provided as a return means. A proximal end portion 16 a of the spring 16 is fixed to the first structure 11, and a distal end portion 16 b is fixed to the second structure 14. A base end portion of the shift lever 2 a is connected to the upper portion of the second structure 14.

  Therefore, when the shift lever 2a connected to the upper part of the second structure 14 is operated in the first operation direction A indicated by an arrow in FIG. 2A, the operating force is transmitted through the protrusion 11a to the first structure. As a result, the first structure 11 rotates about the first shaft 12 against the elastic force of the spring 13. On the other hand, when the shift lever 2a is operated in the second operation direction B indicated by an arrow in FIG. 2A, the second structure 14 is centered on the second shaft 15 against the elastic force of the spring 16. Rotate as At this time, the first structure 11 does not rotate. Thus, the shift lever 2a can be tilted in the first operation direction A (shift direction) and in the second operation direction B (select direction) orthogonal to the first operation direction A, respectively.

  As shown in FIG. 1A, the instrument panel 1 is provided with an operation panel 20. A shift gate 21 is provided through the operation panel 20. As shown in FIG. 2B, the shift gate 21 includes a first gate 21a and a second gate 21b extending in parallel in the vertical direction in FIG. 2B, and a space between the first and second gates 21a and 21b. And a third gate 21c for connecting the two. The first gate 21a located on the left side in FIG. 2B has a length in the longitudinal direction (length in the shift direction) that is about half that of the second gate 21b. The third gate 21c extends from the upper end of the first gate 21a in a direction substantially orthogonal to the first gate 21a, and is connected to the second gate 21b at a substantially central portion of the second gate 21b. The shift lever 2a is allowed to move in the first operation direction A (shift direction) along the first and second gates 21a and 21b, and the second operation direction B (select direction) along the third gate 21c. ) Is allowed to move.

  In the present embodiment, the upper end of the first gate 21a and the connection point with the third gate 21c are set to the reference position P1, and the lower end of the first gate 21a is set to the regenerative brake position P2. . Further, the upper end of the second gate 21b is the reverse position P3, the connection point with the third gate 21c located substantially at the center of the second gate 21b is the neutral position P4, and the lower end in the figure is the drive. The position P5 is set. The shift lever 2a is normally held at the reference position P1. The shift lever 2a moves from the reference position P1 to the operation positions P2 to P5 against the biasing force of the springs 13 and 16 by a shift operation. When the operating force is released, the springs 13 and 16 are urged to automatically return from the operating positions P2 to P5 to the reference position P1.

  As shown in FIG. 2 (a), on the base end side (multiaxial structure 10) of the shift lever 2a, a first rotation angle detection device 30a that detects the rotation angle (operation angle θ1) of the first shaft 12; A second rotation angle detection device 30b that detects the rotation angle (operation angle θ2) of the second shaft 15 is provided. As shown in FIG. 1B, the first and second rotation angle detection devices 30a and 30b are connected to the control unit 30c of the shift device 2, respectively. The transmission 3 is connected to the control unit 30c.

<Rotation angle detector>
Next, the first and second rotation angle detection devices 30a and 30b will be described. The first rotation angle detection device 30a and the second rotation angle detection device 30b have substantially the same configuration.

  As shown in FIGS. 3 and 4, the first and second rotation angle detection devices 30 a and 30 b are disposed at the outer end portion of the first shaft 12 or the second shaft 15 (see FIG. 2A). In addition, a disk-shaped holder 31 fixed to the housing is provided. The holder 31 is made of a nonmagnetic material such as resin.

  Around the surface of the holder 31 facing the first shaft 12 or the second shaft 15 (the upper side in FIGS. 3 and 4), an annular yoke fitting portion 31 a is recessed. A cylindrical yoke 32 having an inner diameter substantially equal to the inner diameter of the yoke fitting portion 31a and an outer diameter substantially equal to the outer diameter of the yoke fitting portion 31a is fitted to the yoke fitting portion 31a. The yoke 32 is made of a magnetic material.

  Further, on the surface of the holder 31 on the side facing the first shaft 12 or the second shaft 15, the first and second sections having a substantially arcuate cross section in the radial direction on the inner side in the radial direction from the yoke fitting portion 31 a. Second hall element fixing walls 31b and 31c are erected. Element accommodating recesses 31d and 31e are provided on the inner side surfaces of the first and second Hall element fixing walls 31b and 31c, respectively. Hall elements 33 and 34 as magnetic detection elements are fixed to the element receiving recesses 31d and 31e. The hall elements 33 and 34 are arranged in the corresponding element housing recesses 31d and 31e so that the detection surfaces 33a and 34a (see FIG. 5) are radially inward. In addition, holder through holes 31f that penetrate the holder 31 in the thickness direction are provided in portions of the holder 31 corresponding to the element receiving recesses 31d and 31e, respectively. The lead wires 33b and 34b of the hall elements 33 and 34 are led out to the back side of the holder 31 (lower side in FIGS. 3 and 4) through the holder through hole 31f.

  In addition, a magnet support portion 31g having a circular outer shape is erected at the center of the surface of the holder 31 facing the first shaft 12 or the second shaft 15 (upper side in FIGS. 3 and 4). ing. The magnet support portion 31g is formed lower than the first and second Hall element fixing walls 31b and 31c. A cylindrical magnet 35 having an inner diameter slightly larger than the outer diameter of the magnet support portion 31g is rotatably supported by the magnet support portion 31g.

  Engaging recesses 35a and 35b are formed in the surface of the magnet 35 on the side facing the first shaft 12 or the second shaft 15 (upper side in FIG. 4) so as to form a pair in the radial direction. In a state where the magnet 35 is rotatably supported by the magnet support portion 31g of the holder 31, the engagement concave portions 35a and 35b are connected to the engagement convex portion 36 (see FIG. 4) of the first shaft 12 or the second shaft 15. Arranged to engage in the circumferential direction. Thereby, the magnet 35 can rotate integrally with the first shaft 12 or the second shaft 15.

  As shown in FIG. 5, the magnet 35 according to the present embodiment is a single cylinder having a magnetic field orientation in a direction (vertical direction in FIG. 5) along a straight line connecting a pair of engaging recesses 35a and 35b. As shown by the arrows in FIG. 5, the four-pole magnetic poles were formed by magnetizing the member in the opposite direction along the direction of the magnetic field orientation and with the engagement recesses 35a and 35b as boundaries. An anisotropic magnet.

  As shown in FIG. 5, the magnet 35 is arranged so that the boundary between the magnetic poles where the engaging recesses 35a and 35b are not formed faces the hall elements 33 and 34 in a state where the shift lever 2a is at the reference position P1. Is done. The magnetic flux density passing through the Hall elements 33 and 34 and the direction of the magnetic flux change according to the rotation angle of the magnet 35, that is, the operation angles θ1 and θ2 of the shift lever 2a. For this reason, the Hall elements 33 and 34 receive the magnetic flux from the magnet 35 in the magnetic flux density and the direction of the magnetic flux according to the operation angles θ1 and θ2 of the shift lever 2a. A detection signal S1 corresponding to θ2 is output. The detection signal S1 varies with a period of 180 deg.

  Here, as described above, the magnet 35 is a member that has been magnetically oriented in a direction along a straight line connecting the engaging recesses 35a and 35b that form a pair. It is formed by magnetizing along the easy magnetization axis) and in the opposite direction with the engaging recesses 35a and 35b as the boundary. For this reason, as indicated by the alternate long and short dash line in FIG. 5, in the magnet 35, the direction along the straight line connecting the paired engaging recesses 35 a and 35 b, that is, the direction orthogonal to the opposing direction to the Hall elements 33 and 34. The magnetic force is stronger than the magnetic force in the direction facing the Hall elements 33 and 34. As a result, as indicated by the alternate long and short dash line in FIG. 6, the magnetic flux density on the boundary (0 deg and 180 deg in FIG. 6) side of the magnetic poles opposed to the Hall elements 33 and 34 is not opposed to the Hall elements 33 and 34. The position where the magnetic flux density is lower than the magnetic flux density at the boundary (90 deg and 270 deg in FIG. 6) and the magnetic flux density is highest in the circumferential direction of the magnet 35 is a position away from the boundary between the magnetic poles facing the Hall elements 33 and 34. Become. Therefore, in the sinusoidal detection signal S1 output from the Hall elements 33 and 34, the operation angle (rotation angle) corresponding to the region K1 that can be regarded as a linear output near the boundary between the magnetic poles arranged to face the Hall elements 33 and 34. ) The range of θ1, θ2 is widened. For comparison, the magnetic flux density distribution of a conventional isotropic magnet (four poles) is indicated by a two-dot chain line in FIGS.

  As shown in FIG. 1B, the detection signals output from the first and second rotation angle detection devices 30a and 30b (Hall elements 33 and 34) configured as described above are input to the control unit 30c. . The control unit 30c obtains the operation angle θ2 (see FIG. 2A) of the shift lever 2a in the second operation direction B based on the detection signal input from the second rotation angle detection device 30b, and sets the operation angle θ2 to this operation angle θ2. Based on this, it is determined whether the shift lever 2a is in the first or second gate 21a, 21b. Based on this assumption, the control unit 30c determines the operation angle θ1 in the first operation direction A (see FIG. 2A) of the shift lever 2a based on the detection signal input from the first rotation angle detection device 30a. The operation position of the shift lever 2a is determined. Here, in order to accurately detect the operation angles θ1 and θ2, it is desirable that the detection signal S1 has a sufficient amount of change with respect to the operation angles θ1 and θ2. In the detection signal S1 output from the first rotation angle detection device 30a and the second rotation angle detection device 30b, the control unit 30c defines a region that can be regarded as a linear output (a region of a rotation angle at which the detection signal S1 changes linearly). Using this, the operation position of the shift lever 2a is determined.

  More specifically, the control unit 30c has thresholds TH1 and TH2 (TH1 <0 <TH2) set in advance based on the state where the shift lever 2a is at the reference position P1 and the output value of the detection signal S1 is “0”. Is remembered. The control unit 30c compares the detection signals (voltage values) S1 corresponding to the operation angles θ1 and θ2 of the shift lever 2a with the threshold values TH1 and TH2, and determines the operation position of the shift lever 2a.

  For example, when the detection signal S1 input from the second rotation angle detection device 30b is between the threshold value TH1 and the threshold value TH2, the control unit 30c determines that the shift lever 2a is at the position of the first gate 21a. . In this state, the control unit 30c determines that the shift lever 2a is + θ with respect to the reference position P1 when the detection signal S1 input from the first rotation angle detection device 30a falls below the threshold value TH1 (see FIG. 6). It is determined that the regenerative brake position P2 in the direction is operated. Further, the control unit 30c compares the detection signal S1 input from the second rotation angle detection device 30b with a threshold value TH2 (see FIG. 6), and when the threshold value TH2 is exceeded, the shift lever 2a is moved to the second gate 21b. It is determined that the position is. Then, the control unit 30c determines that the shift lever 2a is the reference when the detection signal S1 input from the first rotation angle detection device 30a exceeds the threshold value TH2 in a state where the shift lever 2a is at the second gate 21b. It is determined that the reverse position P3 is operated in the −θ direction (see FIG. 2A) with respect to the position P1. Further, the control unit 30c determines that the shift lever 2a is the reference when the detection signal S1 input from the first rotation angle detection device 30a falls below the threshold value TH1 while the shift lever 2a is at the position of the second gate 21b. It is determined that the drive position P5 is operated in the + θ direction (see FIG. 2A) with respect to the position P1. Note that the control unit 30c, when the shift lever 2a is at the position of the second gate 21b and the detection signal S1 input from the first rotation angle detection device 30a is between the threshold value TH1 and the threshold value TH2, It is determined that the shift lever 2a has been operated to the neutral position P4. The control unit 30c outputs a switching signal to switch the connection state of the transmission 3 to a connection state corresponding to the detection result.

  Further, as shown in FIG. 6, since the distribution of magnetic flux density around the magnet 35 changes at a cycle of 180 degrees, the pair of Hall elements 33 and 34 arranged opposite to each other with the magnet 35 interposed between them The substantially same detection signal S1 is output with rotation. Based on the detection signals S1 respectively output from the pair of Hall elements 33 and 34, the control unit 30c moves to the rotation angle of each first shaft 12 or the second shaft 15, that is, to each operation direction A and B of the shift lever 2a. Are measured by a double system.

Next, the operation of detecting the operation position of the shift lever 2a by the rotation angle detection device configured as described above will be described.
As shown in FIG. 5, when the shift lever 2a is at the reference position P1, the Hall elements 33 and 34 are disposed opposite to the boundary of the magnetic pole on the side where the magnetic flux density is low. Therefore, the output value of the detection signal S1 is “0”. At this time, the disturbance magnetic field (disturbance magnetism) around the rotation angle detection devices 30a and 30b enters the yoke 32 provided outside the Hall elements 33 and 34, and avoids the boundary between the magnetic poles having a relatively low magnetic flux density. Act on 35. For this reason, in the state where the magnetic flux density passing through the Hall elements 33 and 34 is relatively low, the influence of the disturbance magnetic field acting on the Hall elements 33 and 34 is suppressed.

  When the shift lever 2a is operated to be positioned at the respective operation positions P2 to P5, the magnet 35 rotates together with the first shaft 12 or the second shaft 15, and the hall elements 33, The magnetic flux density passing through 34 and the direction of the magnetic flux change. Due to the change in the magnetic flux density and the direction of the magnetic flux, the detection signal S1 output from the Hall elements 33 and 34 changes. At this time, as described above, the region K1 in which the change of the magnetic flux density with respect to the operation angles θ1 and θ2 is linear is wider than the linear region K2 in the conventional rotation angle detection device, and therefore corresponds to the linear region K1. The range of operation angles θ1 and θ2 that can be detected with high accuracy is wider than that of a conventional rotation angle detection device. For this reason, it is possible to set a wide range of the rotation angles θ1 and θ2 corresponding to the operation positions P2 to P5 of the shift lever 2a. For example, an assembly error or the like occurs and the Hall elements 33 and 34 and the magnet 35 It is possible to suitably prevent the operation position of the shift lever 2a from being erroneously detected when there is a variation in the positional relationship between them.

  When the operating force on the shift lever 2a is released, the shift lever 2a returns to the reference position P1 by the urging force of the springs 13 and 16. For this reason, in a state where the shift lever 2 a is not operated, the magnet 35 is disposed so that the boundary between the magnetic poles faces the Hall elements 33 and 34. That is, in a state where the shift lever 2a is not operated, in other words, in a state where the magnetic flux density passing through the Hall elements 33 and 34 is relatively low, the detection signal S1 output from the Hall elements 33 and 34 varies due to the disturbance magnetic field. Can be prevented. When the shift lever 2a is rotated to the operation positions P2 to P5, the Hall elements 33 and 34 are affected by the disturbance magnetic field, but the Hall elements 33 and 34 are moved along with the rotation of the shift lever 2a. Since the magnetic flux density of the passing magnet 35 is increased, the influence of the disturbance magnetic field is small.

Next, the operational effects of the above embodiment will be described below.
(1) The magnet 35 of the rotation angle detectors 30a and 30b has a magnetic field orientation in a direction perpendicular to the direction of facing the Hall elements 33 and 34 when the boundary of one magnetic pole is disposed opposite to the Hall elements 33 and 34. Therefore, it is easy to be magnetized in a direction perpendicular to the facing direction to the Hall elements 33 and 34. For this reason, when magnetized along the direction of magnetic field orientation, the magnet 35 has a magnetic force in a direction perpendicular to the facing direction to the Hall elements 33 and 34 more than the magnetic force in the facing direction to the Hall elements 33 and 34. Become stronger. As a result, the magnetic flux density on the boundary side of the magnetic pole arranged opposite to the Hall elements 33 and 34 is lower than the magnetic flux density on the boundary side of the magnetic pole not arranged opposite to the Hall elements 33 and 34, and the circumferential direction of the magnet 35 The position where the magnetic flux density is the highest is the position away from the boundary between the magnetic poles facing the Hall elements 33 and 34. Therefore, in the sinusoidal detection signal S1 output from the Hall elements 33 and 34, an operation angle (rotation angle) corresponding to a region K1 that can be regarded as a linear output on the boundary side of the magnetic poles arranged to face the Hall elements 33 and 34. The range of θ1 and θ2 is widened, and the detection range of operation angles (rotation angles) θ1 and θ2 that can be accurately detected can be widened. As a result, it is possible to set a wide range of rotation angles θ1 and θ2 corresponding to each operation position of the shift lever 2a, and the operation positions P2 to P5 of the shift lever 2a are erroneously set by the rotation angle detection devices 30a and 30b. Can be suitably prevented. Further, since the yoke 32 is provided outside the hall elements 33 and 34 so as to surround the magnet 35 and the hall elements 33 and 34, the magnetic flux is preferably prevented from leaking outside the yoke 32. The angles (rotation angles) θ1 and θ2 can be detected with higher accuracy.

  (2) Further, since the region K1 that can be regarded as a linear output in the detection signal S1 is widened, a control process such as making the conventional sinusoidal detection signal S2 linear by calculation becomes unnecessary. Further, since a mechanism for reducing the change in the rotation angle of the rotation shaft with respect to the change in the rotation angle of the shift lever 2a becomes unnecessary, the rotation angle detection devices 30a and 30b, and hence the shift device 2 can be reduced in size. be able to.

  (3) Since the distribution of the magnetic flux density around the four-pole magnet 35 changes in a cycle of 180 degrees, the pair of Hall elements 33 and 34 that are arranged to face each other with the magnet 35 interposed therebetween is rotated with the rotation of the magnet 35. Substantially the same detection signal S1 is output. For this reason, it becomes possible to measure a rotation angle by a double system based on detection signal S1 output from a pair of hall elements 33 and 34, respectively, and to improve the reliability of rotation angle detectors 30a and 30b. Can do. Therefore, the reliability of the shift device 2 is also improved.

  (4) A disturbance magnetic field (disturbance magnetism) around the rotation angle detection devices 30a and 30b enters the yoke 32 provided outside the Hall elements 33 and 34, and avoids the boundary of the magnetic pole having a relatively low magnetic flux density. Act on 35. For this reason, in the state where the magnetic flux density passing through the Hall elements 33 and 34 arranged opposite to the boundary of the magnetic pole of the magnet 35 is relatively low, the influence of the disturbance magnetic field acting on the Hall elements 33 and 34 is affected. Can be suppressed. Further, when the shift lever 2a is rotated from the reference position P1 to the respective operation positions P2 to P5 against the biasing force of the springs 13 and 16, the spring 13 is released when the operation force applied to the shift lever 2a is released. , 16 return to the reference position P1. For this reason, in a state where the shift lever 2 a is not operated, the magnet 35 is disposed so that the boundary between the magnetic poles faces the Hall elements 33 and 34. That is, the influence of the disturbance magnetic field can be suppressed in a state where the shift lever 2a is not operated, in other words, in a state where the magnetic flux density passing through the Hall elements 33 and 34 is relatively low. For this reason, it is possible to prevent the operation positions P2 to P5 of the shift lever 2a from being erroneously detected due to fluctuations in the detection signal S1 output from the Hall elements 33 and 34 due to the disturbance magnetic field, and the shift device. 2 reliability can be improved.

  (5) One cylindrical member that is magnetically oriented in a direction along a straight line that connects the paired engaging recesses 35a and 35b is formed along the direction of the magnetic field orientation and the engaging recesses 35a and 35b. The magnet 35 having four magnetic poles is formed by magnetizing in the opposite direction with respect to. For this reason, for example, compared with the case where the cylindrical magnet 35 is formed from the several member of the shape divided | segmented in the circumferential direction at two places, the magnet 35 can be formed easily.

  Note that, as in the rotation angle detection device 40 shown in FIG. 7A, a magnet 41 having two magnetic poles in which the direction of magnetic field orientation (vertical direction in FIG. 7A) coincides with the direction of magnetization. (See FIG. 7B), the magnetic flux at a position (point C in FIG. 7A) that is in the middle of the boundary between the magnetic poles in the circumferential direction, as shown by a two-dot chain line in FIG. 7A. Density is highest. Therefore, the Hall elements 33 and 34 output sinusoidal detection signals similar to those of the conventional rotation angle detection device as indicated by a two-dot chain line in FIG. 6, and the detection signals can be regarded as linear outputs. Can not be widened. When forming a magnet 51 (see FIG. 8B) having six or more magnetic poles as in the rotation angle detection device 50 shown in FIG. Magnetized in the direction to form a magnetic pole. For this reason, when the direction of magnetic field orientation (the depth direction in FIG. 8A) and the direction of magnetization coincide with each other, as shown by the two-dot chain line in FIG. The magnetic flux density at the middle position (point D in FIG. 8A) is the highest. Therefore, as in the case of forming the two-pole magnetic pole, the Hall elements 33 and 34 output a sine wave-like detection signal similar to that of the conventional rotation angle detection device as indicated by a two-dot chain line in FIG. Therefore, the region that can be regarded as a linear output in the detection signal cannot be widened. That is, when the magnet 35 having four magnetic poles magnetized as in the above embodiment is used, the region K1 that can be regarded as a linear output in the sinusoidal detection signal S1 output from the Hall elements 33 and 34. The range of the rotation angle corresponding to can be widened.

In addition, you may change this Embodiment as follows.
In the above embodiment, the cylindrical magnet 35 is used. However, for example, a square cylindrical magnet may be used and can be changed as appropriate.

In the above embodiment, the magnet 35 is formed from one member, but the cylindrical magnet 35 may be formed from a plurality of members that are divided at two locations in the circumferential direction.
In the above embodiment, the magnet 35 having a magnetic field orientation in a direction along a straight line connecting the engaging recesses 35a and 35b forming a pair is used. However, the present invention is not limited to such a mode. When the boundary of one magnetic pole of the magnet 35 is disposed opposite to the Hall elements 33 and 34, the magnet 35 having a magnetic field orientation in a direction orthogonal to the opposing direction to the Hall elements 33 and 34 is paired. You may incline with respect to the straight line which connects engagement recessed part 35a, 35b.

  In the above embodiment, the engagement recesses 35a and 35b that are paired with the magnet 35 are provided, but the number of the engagement recesses 35a and 35b can be changed as appropriate. Further, the magnet 35 may be provided with an engaging convex portion that engages with the engaging concave portion of the first shaft 12 or the second shaft 15.

In the above-described embodiment, the pair of Hall elements 33 and 34 are disposed to face each other with the magnet 35 interposed therebetween, but one of the Hall elements 33 and 34 may be omitted.
In the above embodiment, the springs 13 and 16 for urging the shift lever 2a toward the reference position P1 are provided. However, the springs 13 and 16 are omitted, and the shift lever 2a does not return from the operation positions P2 to P5. It may be applied to a type of shift device.

  In the above embodiment, the shift lever 2a is set along the first operation direction A to the reference position P1, one side (for example, the reverse position P3) and the other side (drive position P5) of the reference position P1. Although it can move to three positions, it may move to two positions. Moreover, it is good also as a structure which can move to four or more positions. In this case, since the operation position of the shift lever 2a can be detected by presetting a plurality of threshold values corresponding to the operation position in the control unit 30c, the number of rotation angle detection devices 30a and 30b is greatly increased. It is possible to prevent the increase.

  In the above embodiment, the present invention is applied to the rotation angle detection devices 30a and 30b for detecting the operation position of the shift lever 2a of the shift device 2. However, the present invention is not limited to this mode, and the rotation angle detection devices 30a and 30b. May be applied to devices other than the shift device 2.

(A) The perspective view which shows the vehicle arrangement | positioning state of a shift apparatus, (b) The block diagram which shows schematically the electric structure of a shift apparatus. (A) The perspective view which shows schematic structure of a shift apparatus, (b) The top view which shows the shift gate of a shift apparatus. The perspective view of a rotation angle detection apparatus. The exploded perspective view of a rotation angle detection apparatus. The schematic plan view of a rotation angle detection apparatus. The characteristic view which shows the relationship between the rotation angle of a magnet, and magnetic flux density. (A) The schematic plan view of the other rotation angle detection apparatus for demonstrating the effect of the rotation angle detection apparatus of this Embodiment, (b) The perspective view of the magnet of another rotation angle detection apparatus. (A) The schematic plan view of the other rotation angle detection apparatus for demonstrating the effect of the rotation angle detection apparatus of this Embodiment, (b) The perspective view of the magnet of another rotation angle detection apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 2 ... Shift apparatus, 2a ... Shift lever, 3 ... Transmission, 12 ... 1st axis | shaft as a rotating shaft, 13, 16 ... Spring as a return means, 15 ... 2nd axis | shaft as a rotating shaft, 21 ... Shift gate, 30a, 30b ... rotation angle detection device, 32 ... yoke, 33, 34 ... Hall element as magnetic detection element, 35 ... magnet, [theta] 1, [theta] 2 ... rotation angle (operation angle), P1 ... reference position, P2-P5 ... operation Position, S1, S2 ... detection signal.

Claims (5)

A magnet having a four-pole magnetic pole that rotates integrally with the rotating shaft;
A magnetic detection element that is disposed opposite to the outer surface of the magnet and detects a change in magnetic flux density accompanying rotation of the rotation shaft, and outputs a sinusoidal detection signal;
A rotation angle detection device comprising a cylindrical yoke provided outside the magnetic detection element so as to surround the magnet and the magnetic detection element,
The magnet is magnetically oriented in a direction perpendicular to the facing direction of the magnetic detection element when the boundary of one magnetic pole is arranged to face the magnetic detection element, and along the direction of the magnetic field alignment. A rotation angle detection device characterized by being an anisotropic magnet magnetized in this manner. The rotation angle detection device according to claim 1,
The rotation angle detection device further comprising another magnetic detection element disposed opposite to the magnetic detection element with the magnet interposed therebetween. A shift lever that is rotated along a shift gate; and a rotation angle detection device that detects a rotation angle of the shift lever. Based on a detection result of the rotation angle detection device, the connection state of the transmission of the vehicle is determined. A shift device for switching,
The rotation angle detection device includes:
A magnet having a four-pole magnetic pole that rotates integrally with the rotation shaft of the shift lever;
A magnetic detection element that is disposed opposite to the outer surface of the magnet and detects a change in magnetic flux density accompanying rotation of the rotation shaft, and outputs a sinusoidal detection signal;
A rotation angle detection device comprising a cylindrical yoke provided outside the magnetic detection element so as to surround the magnet and the magnetic detection element,
The magnet is magnetically oriented in a direction perpendicular to the facing direction of the magnetic detection element when the boundary of one magnetic pole is arranged to face the magnetic detection element, and along the direction of the magnetic field alignment. A shift device characterized by being an anisotropic magnet magnetized in this manner. The shift device according to claim 3, wherein
A shift device further comprising another magnetic detection element disposed opposite to the magnetic detection element with the magnet interposed therebetween. The shift device according to claim 3 or 4,
A return means for urging the shift lever that has been rotated from the reference position set along the shift gate to the operation position toward the reference position;
The shift device according to claim 1, wherein the magnet has a magnetic pole boundary facing the magnetic detection element in a state where the shift lever is at the reference position.

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