JP5915164B2 - Steering control device - Google Patents

Description

  The present invention relates to a steering control device for a steering device having a tilt mechanism that changes a tilt angle of a steering wheel and an electric motor that drives the tilt mechanism, and relates to a steering control device that controls a supply current of the electric motor.

  The steering control device described in Patent Document 1 changes a tilt angle by driving an electric motor in accordance with an operation of a tilt switch.

JP 2010-840

  As the electric motor rotates, the magnitude of the force acting on the tilt mechanism changes according to the tilt angle. For this reason, when comparing the operation speed of the tilt mechanism when the tilt angle starts to be changed according to the driver's request with the operation speed of the tilt mechanism in the process of changing the tilt angle, the former and the latter are Not necessarily equal.

  On the other hand, when changing the tilt angle, the driver stops the instruction to change the tilt angle when the tilt angle requested by the driver is reached. However, when the operation speed of the tilt mechanism increases as described above, it is difficult to stop the tilt angle change instruction at the timing when the tilt angle reaches the required position.

  In order to solve the above problems, an object of the present invention is to provide a steering control device having high operability when adjusting a tilt angle.

(1) A first means is a control device for a steering device having the invention according to claim 1, that is, a tilt mechanism that changes a tilt angle of a steering wheel and an electric motor that drives the tilt mechanism. In the steering control device that controls the supply current of the electric motor, the steering control device includes a calculation unit in which a relationship between the tilt angle and the supply current of the electric motor is defined in advance, and the supply current of the electric motor is calculated using the calculation unit The calculation means includes a map in which a relationship between the tilt angle and a supply current of the electric motor is defined, and the map is a first motor current map used when increasing the tilt angle, and A second motor current map for use in reducing the tilt angle, the second motor current map Supply current of the electric motor is determined based is summarized as smaller than the supply current of said electric motor to be determined based on the first motor current map.

According to this invention, since the supply current of the electric motor is controlled using the relationship between the predetermined tilt angle and the supply current of the electric motor, the operating speed of the tilt mechanism can be controlled according to the tilt angle. . For this reason, the operability when adjusting the tilt angle can be improved by defining the above relationship so as not to cause a change in the operating speed of the tilt mechanism that makes it difficult to adjust the tilt angle. In addition, since the supply current of the electric motor is controlled using a predetermined relationship, the calculation load of the control device is reduced compared to a configuration in which the supply current of the electric motor is controlled by feedback control. In addition, the current supplied to the electric motor can be calculated by applying the tilt angle at that time to the map. For this reason, compared with the structure which calculates the supply current of an electric motor using a computing equation, the calculation load of a control apparatus becomes small.

(2) second means, the invention i.e. according to claim 2, wherein the computing means according to claim 1 comprising an arithmetic expression for calculating the supply current of the electric motor on the basis of the tilt angle The gist of the present invention is a steering control device.

  According to the present invention, the supply current of the electric motor can be calculated by applying the tilt angle at that time to the arithmetic expression. For this reason, the storage capacity required for the control device is smaller than the configuration in which the map is stored in advance and the supply current of the electric motor is calculated.

( 3 ) The third means is the invention according to claim 3 , that is, the steering device defines a support member that supports the steering wheel and a changeable range of the tilt angle that is a rotation angle of the support member. The steering control device includes a first limit angle and a second limit angle as angles at both ends in the changeable range of the tilt angle, respectively, and the tilt angle and the first limit angle or the A range in which the difference from the second limit angle is equal to or less than a predetermined angle is a near limit range, and a range other than the near limit range of the changeable range is a normal range. The operation speed of the tilt mechanism when the angle is within the limit range is the operation speed VA, and the operation of the tilt mechanism when the tilt angle is within the normal range. As degree of operating speed VB, the operating speed VA is according to claim 1 or 2 relationship and has a supply current of predefined the tilt angle and the electric motor so that the operating speed lower than VB The gist of the present invention is a steering control device.

  When the rotation of the support member is restricted by the restriction member while the operation speed of the tilt mechanism is high, one or both of these members may be deformed due to the contact between the support member and the restriction member. The above-described invention focuses on this point and reduces the operation speed of the tilt mechanism when the tilt angle is in the vicinity of the limit. For this reason, a possibility that at least one of a support member and a control member will change becomes small.

( 4 ) The fourth means is the invention according to claim 4 , that is, when a current is supplied to the electric motor and a period during which the tilt angle does not change is continued beyond a predetermined period, The gist of the steering control device according to any one of claims 1 to 3 , wherein the tilt angle at that time is learned as a reference tilt angle.

  In the steering device, the tilt angle recognized by the control device may deviate from the actual tilt angle due to the accumulation of displacement in the tilt mechanism or aging degradation. On the other hand, when the operation of the tilt mechanism is restricted by contact with another member, the state in which the tilt angle does not change is continued even when current is supplied to the electric motor. The above-described invention focuses on these points to learn the reference tilt angle. For this reason, there is a high possibility that the deviation between the tilt angle recognized by the control device and the actual tilt angle is eliminated.

( 5 ) The steering means according to any one of claims 1 to 4 , wherein the fifth means estimates the tilt angle based on the invention according to claim 5 , that is, the induced voltage of the electric motor. It is a summary.

  In the present invention, since the tilt angle is calculated based on the induced voltage of the electric motor, in a steering apparatus that is not provided with a sensor that measures the tilt angle, the supply current to the electric motor can be determined according to the tilt angle. it can.

  The present invention provides a steering control device having high operability when adjusting a tilt angle.

The schematic diagram which shows the structure of the steering device containing the electronic control apparatus about the electronic control apparatus of one Embodiment of this invention. In the steering device of the embodiment, (a) is a schematic diagram showing the component force of the tilt screw axial force when the tilt angle is the lower limit angle, and (b) is the component force of the tilt screw axial force when the tilt angle is the upper limit angle. FIG. The graph which shows the relationship between the vertical component force of a tilt screw axial force, and a tilt angle about the steering device of embodiment. The graph which shows the relationship between a tilt angle and its operation speed about the steering device of embodiment. The map which shows the relationship between the tilt angle memorize | stored in the electronic controller of embodiment, and a motor current. The flowchart which shows the procedure of the motor current determination process performed by the electronic controller of embodiment. The flowchart which shows the procedure of the reference | standard rotation angle learning process performed by the electronic controller of embodiment. Regarding other embodiments of the present invention, (a) is a map showing the relationship between the tilt angle stored in the electronic control device and the motor current, and (b) is the relationship between the tilt angle in the steering device and its operating speed. Graph showing.

With reference to FIG. 1, the whole structure of the steering apparatus 1 is demonstrated.
The steering device 1 is provided with a steering wheel 2, a steering shaft 11, a column tube 12, a column bracket 13, a holding member 21, and a tilt screw shaft 22. The steering device 1 includes a tilt screw nut 23, a rotation angle sensor 24, a flexible shaft 25, a transmission mechanism 26, an electric motor 31, a speed reduction mechanism 32, an electronic control device 33, and an operation unit 34.

  The steering wheel 2 is connected to one end of the steering shaft 11. The steering shaft 11 is inserted through the column tube 12. The column tube 12 supports the steering shaft 11 so as to be rotatable around a central axis Ta in the longitudinal direction. The other side of the steering shaft 11 with respect to the steering wheel 2 is connected to a turning mechanism (not shown). The steered mechanism changes the direction of the steered wheels according to the operation of the steering wheel 2.

  The column tube 12 is provided with a first column rib 17 protruding outward in the radial direction on the outer surface of the vehicle front side. The column tube 12 is connected to the mounting rib 16 of the vehicle via the first column rib 17 so as to be rotatable about the tilt center axis P. Further, the column tube 12 is provided with a second column rib 18 protruding outward in the radial direction on an outer surface substantially facing the first column rib 17 with the central axis Ta as a center. In addition, the column tube 12 is provided with a third column rib 19 protruding outward in the radial direction of the column tube 12 at a position on the rear side of the vehicle parallel to the central axis Ta from a position where the second column rib 18 is provided. Yes.

  1 indicates the intersection between the perpendicular of the central axis Ta passing through the tilt central axis P and the central axis Ta. In the following, the tilt angle θt increases when one end of the column tube 12 on the steering wheel 2 side rotates about the tilt central axis P so as to face the upper side in the gravitational direction, and rotates so as to face the lower side in the gravitational direction. The description will be continued assuming that the tilt angle θt decreases.

  The top plate of the column bracket 13 is fixed to a mounting stay 15 of the vehicle by mounting bolts 14. A holding member 21 is attached to the lower end of the column bracket 13 so as to be rotatable around a central axis S parallel to the tilt central axis P. The holding member 21 is provided with an insertion port for the tilt screw shaft 22. Further, the tilt screw nut 23 and the rotation angle sensor 24 are held inside the holding member 21.

  A spiral groove is formed on the cylindrical surface of the tilt screw shaft 22. The groove of the tilt screw shaft 22 is formed from one end side to immediately before the end portion on the other end side. Therefore, the tilt screw shaft 22 has a first cylindrical portion in which a groove is formed and a second cylindrical portion in which no groove is formed. The first cylindrical portion is inserted into the tilt screw nut 23. A bevel gear is attached to the end of the first cylindrical portion. A bevel gear of the first cylindrical portion is inserted into the transmission mechanism 26. The direction of the groove of the tilt screw shaft 22 is a direction approaching the column bracket 13 from the holding member 21 by forward rotation. The time when the tilt screw shaft 22 rotates forward is when the tilt screw shaft 22 rotates clockwise when viewed from the side of the column tube 12 along the longitudinal center axis Tb. The tilt screw shaft 22 rotates in the reverse direction when it rotates counterclockwise when viewed from the column tube 12 side along the central axis Tb. The groove of the tilt screw shaft 22 is a ratio (hereinafter simply referred to as a rotational movement ratio) between an amount of movement of the tilt screw shaft 22 in the axial direction and a change amount of a rotational angle θk (hereinafter simply referred to as a rotational angle θk) around the axial direction. Is set to a predetermined value. 1 indicates an intersection between the central axis Tb in the longitudinal direction of the tilt screw shaft 22 and the central axis Ta.

The tilt screw nut 23 has a groove on the inner surface that meshes with the groove of the tilt screw shaft 22.
The rotation angle sensor 24 detects the rotation angle around the central axis Tb of the tilt screw shaft 22 as a rotation angle θk in the range of 0 ° to 359 °.

The flexible shaft 25 has a bevel gear that meshes with a bevel gear that is attached to the tilt screw shaft 22 at one end.
The transmission mechanism 26 is attached to the column bracket 13 so as to be rotatable about an axis (not shown) parallel to the tilt center axis P. A bevel gear of the tilt screw shaft 22 and a bevel gear of the flexible shaft 25 are inserted into the transmission mechanism 26. Inside the transmission mechanism 26, the tilt screw shaft 22 and the flexible shaft 25 are supported by bearings (not shown) so that the bevel gears mesh with each other at right angles and can rotate.

  The electric motor 31 is attached to the second column rib 18 so that the central axis of the end of the flexible shaft 25 on the electric motor 31 side and the rotation central axis of the rotor of the electric motor 31 intersect perpendicularly. The electric motor 31 is attached to the second column rib 18 via the speed reduction mechanism 32. The speed reduction mechanism 32 transmits the rotational torque τ of the electric motor 31 to the flexible shaft 25.

  The operation unit 34 is provided with an increase button for instructing an increase in the tilt angle θt and a decrease button for instructing a decrease. When the increase button is pressed by the user, an instruction signal Ss indicating an instruction to increase the tilt angle θt is generated by the operation unit 34. On the other hand, when the decrease button is pressed by the user, an instruction signal Ss indicating an instruction to decrease the tilt angle θt is generated by the operation unit 34.

  The electronic control device 33 is attached to the second column rib 18. The electronic control device 33 controls the electric motor 31 based on signals output from the operation unit 34 and the rotation angle sensor 24. Further, the electronic control device 33 has a storage unit (not shown) for storing various information. Note that reference signs PQ to RS shown in FIG. 1 are solid lines connecting the reference signs P to S, respectively, and are not actual members provided in the steering device 1.

The operation of the steering device 1 will be described.
When an instruction signal Ss indicating an instruction to increase the tilt angle θt is generated by operating the operation unit 34 by the user, the electronic control unit 33 supplies a positive motor current Im to the electric motor 31. On the other hand, a negative motor current Im is supplied to the electric motor 31 when an instruction signal Ss indicating an instruction to reduce the tilt angle θt is generated by operating the operation unit 34 by the user.

  The electric motor 31 rotates forward when the positive motor current Im is supplied, and rotates reversely when the negative motor current Im is supplied. The rotational torque τ of the electric motor 31 is transmitted to the tilt screw shaft 22 via the speed reduction mechanism 32, the flexible shaft 25, and the transmission mechanism 26. When the electric motor 31 is rotating forward, the tilt screw shaft 22 rotates forward, and when the electric motor 31 is rotating backward, the tilt screw shaft 22 rotates backward. As the tilt screw shaft 22 rotates with respect to the tilt screw nut 23, the rotational torque τ of the electric motor 31 is converted into an axial force Jf of the tilt screw shaft 22 (hereinafter referred to as a tilt screw axial force Jf).

  The tilt screw axial force Jf moves the tilt screw shaft 22 in the axial direction. As the tilt screw shaft 22 moves, the transmission mechanism 26, the second column rib 18, the column tube 12, the steering shaft 11, and the steering wheel 2 are integrally rotated about the tilt center axis P, and the tilt angle θt is increased. Be changed. A geometric relationship (hereinafter referred to as a geometric relationship) between the amount of movement of the tilt screw shaft 22 in the axial direction and the tilt angle θt is expressed by a predetermined arithmetic expression. Then, when the tilt screw shaft 22 rotates forward, the tilt angle θt increases. As the tilt screw shaft 22 rotates in the reverse direction, the tilt angle θt decreases. Hereinafter, the tilt angle θt when the tilt screw shaft 22 is lowered in the axial direction and the transmission mechanism 26 contacts the holding member 21 and reaches the lower limit is defined as a reference tilt angle θts of 0 °.

  With reference to FIG. 2 and FIG. 3, the relationship between the vertical component force Ef of the tilt screw axial force Jf (hereinafter referred to as the vertical component force Ef) and the tilt angle θt will be described. Reference signs P to S in FIGS. 2A and 2B respectively correspond to reference signs P to S shown in FIG. Moreover, the codes PQ to RS in FIGS. 2A and 2B respectively correspond to the codes PQ to RS shown in FIG. Also, the axis Kj shown in FIGS. 2A and 2B represents the reference tilt angle θts. Moreover, the code | symbol Sj shown to Fig.2 (a) and FIG.2 (b) shows the axis | shaft of a horizontal direction (henceforth the horizontal axis Sj).

  FIG. 2A shows a state where the transmission mechanism 26 contacts the tilt screw nut 23 and the tilt angle θt becomes the reference tilt angle θts. FIG. 2B shows a state in which the tilt angle θt is increased from the state shown in FIG. 2A and the upper limit is reached by the second cylindrical portion of the tilt screw shaft 22 contacting the groove of the tilt screw nut 23. Show. As the tilt angle θt increases, as shown in FIG. 2B, the angle θf (hereinafter simply referred to as the tilt screw shaft angle θf) formed by the tilt screw axial force Jf with respect to the horizontal axis Sj increases. The component force Ef increases. That is, as the tilt angle θt increases, the ratio of the vertical component force Ef to the tilt screw axial force Jf increases as shown in FIG. For this reason, when the tilt screw axial force Jf is decreased as the tilt angle θt increases, the change in the vertical component force Ef becomes smaller.

  Further, the downward force Kf in the gravity direction due to the weight of the member supported by the tilt screw shaft 22 contributes to the tilt screw axial force Jf when the tilt angle θt is decreased. For this reason, if the tilt screw axial force Jf when decreasing the tilt angle θt is made smaller than when increasing the tilt angle θt, the vertical component force Ef when switching between the operation for increasing the tilt angle θt and the operation for decreasing it is changed. Change is smaller.

The motor current map will be described with reference to FIGS. 4 and 5.
In the electronic control unit 33, the motor current is set to the tilt angle θt so that the vertical component force Ef is constant with respect to the tilt angle θt and the operation speed V is constant with respect to the tilt angle θt as shown in FIG. Accordingly, as shown in FIG. 5, a predetermined first motor current map Ip1 and second motor current map Ip2 are stored in the storage unit. The first motor current map Ip1 is a motor current map used when increasing the tilt angle θt, and the second motor current map Ip2 is a motor current map used when decreasing the tilt angle θt. As shown in FIG. 5, the motor current Im determined by the second motor current map Ip2 is smaller than the motor current Im determined by the first motor current map Ip1.

The operation of the electronic control device 33 will be described with reference to FIG.
The electronic control device 33 acquires the instruction signal Ss from the operation unit 34. Further, the electronic control unit 33 acquires the rotation angle θk from the rotation angle sensor 24. The electronic control unit 33 sets the amount of change in the rotation angle θk when the tilt screw shaft 22 rotates in the positive direction as a positive amount of change. Further, the electronic control unit 33 sets the amount of change in the rotation angle θk when the tilt screw shaft 22 rotates in the reverse direction as a negative amount of change. In the storage unit of the electronic control unit 33, the rotation angle θk corresponding to the lower limit tilt angle θt is stored as the reference rotation angle θs. The electronic control unit 33 calculates the total rotation angle θd around the center axis Tb of the tilt screw shaft 22 by calculating the total value of the positive change amount or the negative change amount from the rotation angle θk of the reference rotation angle θs. .

  The electronic control unit 33 calculates the amount of movement of the tilt screw shaft 22 in the axial direction based on the rotational movement ratio and the total rotational angle θd. Then, the tilt angle θt is measured based on the amount of movement of the tilt screw shaft 22 in the axial direction and the geometric relationship. One of the first motor current map Ip1 and the second motor current map Ip2 is selected by the electronic control unit 33 based on the instruction signal Ss acquired from the operation unit 34. In the selected motor current map, the motor current Im corresponding to the measured value of the tilt angle θt is determined by the electronic control unit 33 as the current supplied to the electric motor 31.

  In parallel with the operation of determining the motor current Im, the electronic control device 33 supplies the negative motor current Im to the electric motor 31 and starts the change to decrease the tilt angle θt, and then the rotation angle θk changes. When the non-period exceeds the predetermined period tx, an operation of learning the rotation angle θk as the reference rotation angle θs is also performed.

  With reference to FIG. 6, the flow of the motor current determination process of the electronic control unit 33 will be specifically described. The electronic control unit 33 repeatedly executes the motor current determination process of FIG. 6 at a predetermined cycle.

  In step S11, it is determined whether or not the instruction signal Ss is generated by the operation unit 34. If a negative determination is made in step S11, the motor current determination process ends. On the other hand, when an affirmative determination is made in step S11, in step S12, the tilt angle θt is measured based on the rotation angle θk detected by the rotation angle sensor 24.

In step S13, the motor current Im corresponding to the measured value of the tilt angle θt in step S12 is determined with reference to the motor current map selected according to the instruction signal Ss.
In step S 14, the motor current Im determined in step S 13 is supplied to the electric motor 31.

  With reference to FIG. 7, the flow of the reference rotation angle learning process of the electronic control unit 33 will be specifically described. The electronic control unit 33 repeatedly executes the reference rotation angle learning process of FIG. 7 in a predetermined cycle in parallel with the motor current determination process.

  In step S21, it is determined whether or not the period during which the rotation angle θk does not change after the start of the supply of the motor current Im exceeds the predetermined period tx. If a negative determination is made in step S21, the reference rotation angle learning process is terminated.

  If an affirmative determination is made in step S21, it is determined in step S22 whether or not the period during which the rotation angle θk does not change exceeds the predetermined period tx since the start of the decrease in the tilt angle θt. If an affirmative determination is made in step S22, the rotation angle θk detected by the rotation angle sensor 24 is reset to the reference rotation angle θs in step S23. If a negative determination is made in step S22, the process proceeds to step S24. In step S24, the supply of the motor current Im is stopped.

(Effect of embodiment)
According to the steering device 1 of the present embodiment, the following effects can be obtained.
(1) The steering device 1 includes an electronic control device 33 in which the relationship between the tilt angle θt and the motor current Im of the electric motor 31 is defined in advance, and the motor current Im of the electric motor 31 is calculated using the electronic control device 33. Control.

  According to this configuration, since the motor current Im of the electric motor 31 is controlled using the relationship between the predetermined tilt angle θt and the motor current Im (supply current) of the electric motor 31, the operating speed V of the tilt mechanism is It can be controlled according to the tilt angle θt. For this reason, the operability when adjusting the tilt angle θt can be improved by defining the above relationship so as not to cause a change in the operating speed V of the tilt mechanism that makes it difficult to adjust the tilt angle θt. In addition, since the motor current Im of the electric motor 31 is controlled using a predetermined relationship, the calculation load of the electronic control device 33 is smaller than the configuration in which the motor current Im of the electric motor 31 is controlled by feedback control. Become.

(2) The electronic control unit 33 includes a map in which the relationship between the tilt angle θt and the motor current Im of the electric motor 31 is determined.
According to this configuration, the motor current Im of the electric motor 31 can be calculated by applying the tilt angle θt at that time to the motor current map. For this reason, compared with the structure which calculates the motor current Im of the electric motor 31 using an arithmetic formula, the calculation load of the electronic control apparatus 33 becomes small.

  (3) When the electronic control unit 33 supplies the motor current Im to the electric motor 31 so that the tilt angle θt decreases, the period in which the tilt angle θt does not change continues beyond the predetermined period tx. Then, the rotation angle θk at that time is learned as the reference rotation angle θs.

  In the steering device, the tilt angle θt recognized by the electronic control device 33 may deviate from the actual tilt angle θt due to accumulation of deviation in the tilt mechanism, aging deterioration, or the like. On the other hand, when the operation of the tilt mechanism is restricted by contact with another member, the state where the tilt angle θt does not change continues even if the motor current Im is supplied to the electric motor 31. The above configuration focuses on these points and learns the reference rotation angle θs. For this reason, there is a high possibility that the deviation between the tilt angle θt recognized by the electronic control unit 33 based on the reference rotation angle θs and the actual tilt angle θt is eliminated.

  (4) The electronic control unit 33 supplies the motor current Im to the electric motor 31 to change the tilt angle θt, and when the period during which the rotation angle θk does not change exceeds the predetermined period tx, the motor current Im Stop supplying.

When the motor current Im is supplied to the electric motor 31 for rotation and the period during which the rotation angle θk does not change exceeds the predetermined period tx, there is a high possibility of being in the following two states.
(A) The electric motor 31 is driven so that the tilt angle θt decreases, but the transmission mechanism 26 is in contact with the holding member 21.
(B) Although the electric motor 31 is driven so that the tilt angle θt increases, the groove formed on the inner surface of the tilt screw nut 23 is in contact with the second cylindrical portion.

  According to the above configuration, the electric motor 31 is stopped in the case of (A) or (B), and the deformation after the transmission mechanism 26, the tilt screw shaft 22, and the tilt screw nut 23 come into contact with each other is suppressed. Can do.

  The present invention includes embodiments other than the above-described embodiment. Hereinafter, the modification of the said embodiment as other embodiment of this invention is shown. The following modifications can be combined with each other.

  In the above embodiment (FIG. 6), the motor current Im corresponding to the tilt angle θt is determined by referring to the motor current map. However, the electronic control unit 33 can also store an arithmetic expression for calculating the motor current Im of the electric motor 31 based on the tilt angle θt. Thus, the motor current Im of the electric motor 31 can be calculated by applying the tilt angle θt at that time to the arithmetic expression. For this reason, the storage capacity required for the electronic control unit 33 is reduced as compared with the configuration in which the motor current map is stored in advance and the motor current Im of the electric motor 31 is calculated.

  In the above embodiment (FIG. 1), the motor current Im is determined using one motor current map. Further, each of the transmission mechanism 26 and the tilt screw nut 23 is a restricting member that restricts the rotation of the tilt screw shaft 22 and determines the changeable range of the tilt angle θt. The tilt screw shaft 22 is a support member that supports the transmission mechanism 26, the column tube 12, the steering shaft 11, and the steering wheel 2. However, as shown in FIGS. 8A and 8B, the angles at both ends in the changeable range of the tilt angle θt are respectively the first limit angle and the second limit angle, and the tilt angle θt and the first limit angle are set. Alternatively, a range in which the difference from the second limit angle is equal to or less than a predetermined angle can be set as the near limit range, and a range other than the near limit range in the changeable range can be set as the normal range. In this case, as shown in FIG. 8B, the electronic control unit 33 sets the operation speed V of the tilt mechanism when the tilt angle θt is within the limit range as the operation speed VA, and the tilt angle θt is within the normal range. The operation speed V of the tilt mechanism at a certain time is defined as an operation speed VB. Then, a motor current map as shown in FIG. 8A showing the relationship between the tilt angle θt defined in advance so that the operating speed VA is less than the operating speed VB and the motor current Im of the electric motor 31 is stored. When rotation of the support member is restricted by the restriction member in a state where the operation speed V of the tilt mechanism is high, one or both of these members may be deformed due to contact between the support member and the restriction member. In this configuration, paying attention to this point, since the operating speed V of the tilt mechanism when the tilt angle θt is in the range near the limit is reduced, the possibility that at least one of the support member and the regulating member is deformed is reduced.

  In the above embodiment (FIG. 6), when the motor current Im is supplied to the electric motor 31 so that the tilt angle θt decreases, the period in which the tilt angle θt does not change continues beyond the predetermined period tx. When the user is in the middle of learning, the current tilt angle θt is learned as the reference tilt angle θts. However, when the motor current Im is supplied to the electric motor 31 so as to increase the tilt angle θt, and when the period during which the tilt angle θt does not change exceeds the predetermined period, the rotation angle at that time It is also possible to learn θk as the reference rotation angle θs.

According to this configuration, similarly to the above-described embodiment, there is a high possibility that the deviation between the tilt angle θt recognized by the electronic control device 33 and the actual tilt angle θt is eliminated.
In the above embodiment (FIG. 7), the reference rotation angle θs is learned when the tilt angle θt is adjusted in accordance with the operation by the user. However, the tilting is performed in order to make it easier for the user to board the vehicle. The reference rotation angle θs may be learned when the angle θt is automatically raised to the upper limit and the steering wheel 2 is retracted so as not to hinder the user's riding operation.

  In the above embodiment (FIG. 1), the rotation angle θk of the tilt screw shaft 22 is detected, but the rotation angle of the rotor is estimated based on the induced voltage (counterelectromotive voltage) of each phase of the electric motor 31 and the like. The tilt angle θt can also be calculated based on the estimation result. Thus, the motor current Im supplied to the electric motor 31 can be determined according to the tilt angle θt without using a sensor for detecting the tilt angle θt.

  In the above embodiment (FIG. 1), the steering device 1 is configured in which the steering shaft 11 and the steering mechanism are mechanically coupled. However, the steering shaft 11 and the steering mechanism are independent, and the present invention is also applied to a steer-by-wire type steering apparatus that controls the steering mechanism using an electric motor or the like as a power source according to the rotation of the steering shaft 11. can do.

  In the above embodiment (FIG. 1), the tilt angle θt is measured by detecting the rotation angle θk of the tilt screw shaft 22 as the rotation amount, but the position at which the displacement amount of the tilt screw shaft 22 in the central axis Tb direction is measured. It is also possible to provide a sensor and measure the tilt angle θt based on the amount of displacement detected by the position sensor.

  In the above embodiment (FIG. 1), the steering device 1 has only a tilt mechanism that can adjust the tilt angle θt, but the position of the steering wheel 2 in the direction of the central axis Ta can be adjusted. The present invention can also be applied to a steering apparatus that further includes a telescopic mechanism.

  In the above embodiment (FIG. 1), the rotation angle sensor 24 is used as the detection means for measuring the tilt angle θt. However, the rotation angle sensor that detects the rotation angle of the rotor of the electric motor 31 or around the tilt center axis P A rotation angle sensor that directly detects the rotation angle as the tilt angle θt can also be used as the detection means.

  In the above embodiment (FIG. 7), the reference rotation angle θs is learned. However, in the case of using detection means that directly detects the tilt angle θt, the reference tilt angle θts when the support member is in contact with the regulating member. Can also learn.

  In the above embodiment (FIG. 1), the tilt angle θt is changed by rotating the tilt screw shaft 22 relative to the tilt screw nut 23 as a support member for changing the tilt angle θt. However, the tilt angle θt can also be changed by directly rotating the column tube 12 that rotatably supports the steering shaft 11 as a support member.

  In the above embodiment (FIG. 1), the column tube 12 is supported by the tilt screw shaft 22. However, the tilt angle θt can be changed by supporting the column tube 12 with the rack shaft of the rack and pinion mechanism and rotating the pinion gear as a rotating member.

  In the above-described embodiment (FIG. 1), the transmission mechanism 26 contacts the holding member 21 as the tilt screw shaft 22 is lowered in the axial direction, and the tilt angle θt when reaching the lower limit is the reference tilt angle of 0 °. It was set as θts. However, the tilt angle θt when the column tube 12 is parallel to the horizontal direction can be set to a reference tilt angle θts of 0 °.

  DESCRIPTION OF SYMBOLS 1 ... Steering device, 2 ... Steering wheel, 11 ... Steering shaft (support member), 12 ... Column tube (support member), 13 ... Column bracket, 14 ... Mounting bolt, 15 ... Mounting stay, 16 ... Mounting rib, 17 ... 1st column rib, 18 ... 2nd column rib, 19 ... 3rd column rib, 21 ... Holding member (regulation member), 22 ... Tilt screw shaft (support member), 23 ... Tilt screw nut (regulation member), 24 ... Rotation angle sensor (Detection means), 25 ... flexible shaft, 26 ... transmission mechanism (regulation member), 31 ... electric motor, 32 ... deceleration mechanism, 33 ... electronic control device (steering control device, calculation means), 34 ... operation unit.

Claims (5)

A control device for a steering device having a tilt mechanism that changes a tilt angle of a steering wheel and an electric motor that drives the tilt mechanism, and a steering control device that controls a supply current of the electric motor,
Comprising computing means in which the relationship between the tilt angle and the supply current of the electric motor is defined in advance, the supply current of the electric motor is controlled using this computing means ,
The calculation means includes a map in which a relationship between the tilt angle and a supply current of the electric motor is defined,
The map includes a first motor current map used when increasing the tilt angle, and a second motor current map used when decreasing the tilt angle;
The steering control device , wherein a supply current of the electric motor determined based on the second motor current map is smaller than a supply current of the electric motor determined based on the first motor current map . The steering control device according to claim 1, wherein the calculation means includes an arithmetic expression for calculating a supply current of the electric motor based on the tilt angle. The steering device includes a support member that supports the steering wheel, and a regulating member that defines a changeable range of the tilt angle that is a rotation angle of the support member.
In the steering control device, the angles at both ends in the changeable range of the tilt angle are set as a first limit angle and a second limit angle, respectively, and a difference between the tilt angle and the first limit angle or the second limit angle is predetermined. A range that is equal to or less than an angle is a range near the limit, and a range other than the range near the limit of the changeable range is a normal range,
The calculation means sets the operation speed of the tilt mechanism when the tilt angle is in the range near the limit as the operation speed VA, and operates the operation speed of the tilt mechanism when the tilt angle is in the normal range. 3. The steering control device according to claim 1, wherein a speed VB has a relationship between the tilt angle and a supply current of the electric motor that are defined in advance so that the operation speed VA is less than the operation speed VB. 4. . When is supplying current to the electric motor, and when the period in which the tilt angle does not change is continued beyond a predetermined period, according to claim 1-3 to learn the tilt angle at that time as a reference tilt angle The steering control device according to any one of the above. The steering control device according to any one of claims 1 to 4 , wherein the tilt angle is estimated based on an induced voltage of the electric motor.