JP2009226990A - Steering device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steering device securing a good steering feel. <P>SOLUTION: The steering device 1 inlcudes: an input shaft 3 to transmit a steering angle θ input to a steering wheel 2; an external thread 3a disposed on an external circumferential surface of the input shaft 3; a movable member 8 having an internal thread 8a into which the external thread 3a is screwed; a stopper member 29 located opposite to an axial end face of the movable member 8; a stopper member side magnet 30 disposed on that surface of the stopper member opposite to the axial end face of the movable member 8; and a movable member side magnet 31 different in polarity from the stopper member side magnet 30, disposed at that position on the axial end face of the movable member 8 opposite to the stopper member side magnet 30. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a steering apparatus suitable for being applied to vehicles such as passenger cars, trucks, and buses.

  A steering device applied to a vehicle includes, for example, a steering wheel, a column shaft, a torque sensor input shaft, an intermediate shaft, a rack and pinion mechanism, and an assist force generation unit, and a torsion bar at any position of the column shaft. The steering force acting on the torsion bar is detected by a torque sensor, and the turning force corresponding to the steering force is generated by the assist force generator and transmitted to the rack bar of the rack and pinion mechanism, for example. Has been done.

  In recent years, a so-called steer-by-wire type steering device has been proposed, and a steering angle corresponding to the steering angle is detected without detecting a steering angle input by a steering wheel and via a mechanical power transmission mechanism. Is generated on the wheels. In such a steering device, the portion that detects the steering angle and the portion that generates the turning angle are not mechanically connected. Therefore, it is necessary to regulate the steering angle in the portion that detects the steering angle. Arise.

As a means for regulating the steering angle as described above, there is one as described in Patent Document 1, and the rotation of the shaft connected to the steering wheel is screwed into the male screw and the male screw provided on the outer peripheral surface of the shaft. The moving member provided with the mating female screw converts the displacement of the moving member into the axial direction, and the displacement of the moving member in the axial direction is regulated by a stopper positioned opposite to the axial end surface of the moving member, and steering is performed. It is done to regulate the corners.
Japanese Patent Laid-Open No. 2005-186861

  However, in such a steering apparatus, when the steering force is input to the steering wheel, the shaft is rotated, and the moving member moves in the axial direction by the screw mechanism, the axial end surface of the moving member comes into contact with the stopper. In the state where the moving member is fixed in the axial direction by the stopper, if a further steering force is input, the male screw may be bitten by an excessive force with respect to the female screw of the moving member. In addition to adverse effects, the steering wheel is steered in the opposite direction, and when returning from the normal state to the normal state, vibration is generated, which also has a problem of adversely affecting the steering feeling. .

  In view of the above problems, an object of the present invention is to provide a steering device that can ensure a good steering feeling.

To solve the above problem,
The steering device according to the present invention is:
An input shaft for transmitting a steering angle input to the steered wheels, conversion means for converting the steering angle of the input shaft into axial displacement of the input shaft, and a moving member moved in the axial direction by the conversion means A regulating member positioned opposite to the axial end surface of the moving member, a regulating member-side magnet provided on a surface of the regulating member facing the axial end surface of the moving member, and the axial direction of the moving member It is provided with the moving member side magnet in which the polarity differs from the said regulating member side magnet provided in the position facing the said regulating member side magnet of an end surface.

  The steering wheel is a steering wheel, the input shaft is a shaft connected to the steering wheel, and the conversion means is typically a male screw provided on the outer peripheral surface of the input shaft; It may be a screw mechanism constituted by a moving member provided with a female screw threadedly engaged with the male screw, or a groove portion spirally provided on the outer peripheral surface of the input shaft and an inner peripheral surface of the moving member. Similarly, it may be a ball screw mechanism composed of spirally provided grooves and balls that are movably fitted in these grooves.

Here, in the steering device,
It is preferable that the restriction value of the steering angle determined by restricting the axial displacement of the moving member by the restricting member is larger than the maximum steering angle determined by the maximum turning angle of the wheel.

  According to this, when the steering angle is the maximum steering angle, the steering generated in the input shaft and the steered wheel via the conversion means by the repulsive force between the restriction member side magnet and the moving member side magnet. If the repulsive force is set so that the reaction force has a magnitude that determines that the driver cannot rotate the steering wheel any more, that is, a critical value, the steering reaction force becomes the critical value. At this point, the driver can be encouraged to avoid further rotation of the steered wheel.

  In addition, after the steering angle exceeds the maximum steering angle, the steering reaction force becomes equal to or greater than the critical value, and prompts the driver not to further rotate the steering wheel, the restriction member Can abut against the axial end face of the moving member to mechanically restrict the axial displacement of the moving member. Thereby, after the axial displacement of the moving member is restricted by the restricting member, it is possible to prevent the driver from further rotating the steering wheel and causing the conversion means to bite.

  That is, when the converting means is the screw mechanism, the male screw of the input shaft is prevented from being bitten by an excessive force with respect to the female screw of the moving member, and is bitten once. Since it is possible to avoid the operation of returning from the normal state to the normal state, it is possible to prevent the occurrence of vibration during steering and to ensure a good steering feeling.

  Further, even when the converting means is the ball screw mechanism, the ball is prevented from being released from the moving member and the groove portion of the input shaft, and the biting is prevented, and the normal state is changed from the once bited state. Therefore, it is possible to avoid the occurrence of vibration during steering and to ensure a good steering feeling.

  At the same time, when the steering angle is the maximum steering angle, the moving member can be prevented from coming into contact with the restricting member. Therefore, after securing the maximum steering angle necessary for turning, The steering device of the present invention using the restricting member side magnet and the moving member side magnet can be configured.

Furthermore, in the steering device,
Steering angle detection means for detecting the steering angle is provided, and when the steering angle is equal to or greater than the maximum steering angle, the steering angle detection means fixes the detected value of the steering angle to the maximum steering angle. Is preferred.

  According to this, even though the steering angle is the maximum steering angle, the driver steers a larger steering angle against the repulsive force between the moving member side magnet and the restriction member side magnet. In the case of input to a wheel, the steering angle detection means fixes the detected value of the steering angle to the maximum steering angle, so that the timing at which the driver determines that the steering wheel cannot be rotated any more is delayed, or Even when the determination is incorrect, the detected value of the steering angle can be prevented from exceeding the maximum steering angle. Thereby, the control of the steering device can be stabilized.

Furthermore, in the steering device,
Steering reaction force control means for generating a steering reaction force corresponding to the steering angle is provided, and the steering reaction force generated by the steering reaction force control means at the maximum steering angle is reduced to the restriction member side magnet at the maximum steering angle. And the steering reaction force generated by the repulsive force of the moving member side magnet.

In addition, in the steering device,
It is preferable that the steering reaction force control means does not generate the steering reaction force when the steering angle is larger than the maximum steering angle.

  According to this, the steering device in particular is a so-called steer-by-wire type in which a portion for turning a wheel and the steering wheel and the input shaft are not mechanically connected to each other, In the case where the steering reaction force control means for simulating the force is provided, the steering reaction force generated by the steering reaction force control means and the repulsive force between the restriction member side magnet and the moving member side magnet It is possible to ensure continuity with the steering reaction force generated via the conversion means and to ensure a good steering feeling.

  In particular, when the repulsive force between the restriction member-side magnet and the moving member-side magnet can be sufficiently large, when the steering angle exceeds the maximum steering angle, it acts on the steering wheel and the input shaft. The steering reaction force is a combination of the steering reaction force due to the repulsive force and the steering reaction force due to the steering reaction force control means, and can be prevented from becoming excessive.

  ADVANTAGE OF THE INVENTION According to this invention, the steering apparatus which can ensure a favorable steering feeling can be provided.

  The best mode for carrying out the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic view showing a steering apparatus according to the present invention, and FIG. 2 is a schematic sectional view showing the steering apparatus according to the present invention including a central axis.

  As shown in FIG. 1, the steering device 1 of this embodiment includes a steering wheel 2, a shaft 3, a steering unit 4, a steering unit 5, a mechanical connection unit 6, and an EPSECU 7 (Electronic Power Steering Electronic Control Unit).

  Further, as shown in FIG. 2, the steering unit 4 includes a shaft 3, a trapezoidal screw nut 8, a lock plate 9, a guide shaft 10, a housing 11, a worm gear 12, a motor 13, a pulley 14, and a steering angle. And a sensor 15.

  The input side of the shaft 3 is connected to the steering wheel 2, a male screw 3 a is formed on the outer peripheral surface of the shaft 3, and a female screw 8 a of a trapezoidal screw nut 8 is screwed to the male screw 3 a. The output side of the worm gear 12 is fitted to the worm gear 12 by serration, and the pulley 14 is fitted to the output side of the worm gear 12 by serration.

  The shaft 3, the worm gear 12, and the pulley 14 are integrally rotated, and are rotatably supported by bearings appropriately provided for the housing 11. The shaft 3 constitutes an input shaft for transmitting the steering angle θ of the driver input from the steering wheel 2 to the worm gear 12 and the pulley 14. The housing 11 is fixed to the reinforcement of the instrument panel on the vehicle body side.

  The trapezoidal screw nut 8 has a large-diameter portion on the right side in the axial direction and a small-diameter portion on the left side in the axial direction of the shaft 3. A hollow disk-like lock plate 9 is also formed by serration on the small-diameter portion on the left side in the axial direction. The trapezoidal screw nut 8 and the lock plate 9 are fitted in the axial direction of the shaft 3 and are supported by the housing 11 at positions spaced apart from the central axis of the shaft 3 in the radial direction. The guide shaft 10 is configured so as not to rotate in the circumferential direction with respect to the housing 11, and the shaft based on the direction changing action of the screw mechanism constituted by the male screw 3 a and the female screw 8 a as the shaft 3 rotates. 3 are displaced together in the axial direction.

  That is, the screw mechanism constituted by the male screw 3a and the female screw 8a constitutes a conversion means for converting the steering angle θ of the shaft 3 as an input shaft into an axial displacement. Along with this, the screw mechanism also has a function of converting the axial displacement of the trapezoidal screw nut 8 and the lock plate 9 into the circumferential displacement of the shaft 3, that is, the steering angle θ.

  Here, the shaft 3 constitutes an input shaft, and the trapezoidal screw nut 8 and the lock plate 9 constitute a moving member. Here, the male screw 3a and the female screw 8a are right screws, and if the steering wheel 2 is rotated to the right, the trapezoidal screw nut 8 and the lock plate 9 are displaced to the right in the axial direction, and are rotated to the left. The trapezoidal screw nut 8 and the lock plate 9 are displaced to the left in the axial direction.

  The pulley 14 is rotated with the rotation of the shaft 3, and the steering angle sensor 15 detects the rotation angle of the pulley 14 and thus the shaft 3, that is, the steering angle θ, and outputs the detection result to the EPS ECU 7.

  The EPS ECU 7 includes, for example, a CPU, a ROM, a RAM, a data bus that connects them, and an input / output interface. The CPU performs the following processing according to a program stored in the ROM, and controls the steering angle detecting means 7a. The means 7b and the steering reaction force control means 7c are configured. The motor 13 drives the worm gear 12 so that the steering wheel 2 generates a steering reaction force corresponding to the steering angle θ based on the control of the steering reaction force control means 7 c of the EPC ECU 7.

  Further, as shown in FIG. 1, the steered portion 5 includes a turning force generating portion 17 that moves the rack bar 16 in the vehicle width direction by a cylindrical motor (not shown) and a ball screw mechanism, and a pinion that meshes with the rack bar 16. The pinion part 18 provided with tie rod 19, the knuckle arm 20, the knuckle 21, and the wheel 22 comprised with a tire and a wheel are comprised.

  The rack bar 16 is supported by the steering force generator 17 so as to be movable in the vehicle width direction. At both ends of the rack bar 16, tie rods 19 extending in the vehicle width direction are provided with ball joints on the inner side in the vehicle width direction. The vehicle width direction outer side portion of the tie rod 19 is connected to the vehicle rear portion of the knuckle arm 20 extending in the vehicle front-rear direction via a ball joint. Further, the vehicle front portion of the knuckle arm 20 is rigidly coupled to the knuckle 21. The knuckle 21 supports the wheel 22 rotatably.

  The steering angle detection means 7a of the EPS ECU 7 detects the steering angle θ based on the output of the steering angle sensor 15, and the control means 7b of the EPS ECU 7 controls the drive of the motor of the turning force generator 17 based on the steering angle θ. Thus, the driving force generated by the motor is transmitted to the rack bar 16 via the ball screw mechanism.

  That is, when the driver inputs the steering angle θ by the steering wheel 2, the EPS ECU 7 calculates the turning angle δ corresponding to the steering angle θ, and the inside of the turning force generator 17 so as to realize the turning angle δ. By driving the motor, the rack bar 16 is moved in the vehicle width direction via the ball screw mechanism by driving the motor, and accordingly, the turning force is transmitted to the tie rod 19, the knuckle arm 20, and the knuckle 21. The wheel 22 is steered.

  Further, as shown in FIG. 1, the mechanical connecting portion 6 includes a pulley 23 provided around a shaft that is parallel to the axial direction of the shaft 3 and that is spaced downward, and the pulley 14 and the pulley 23 described above. A belt 24 wound around the roller 23, a roller 25 arranged coaxially with the pulley 23, an electromagnetic clutch 26 that transmits the rotational force from the pulley 23 to the roller 25 so as to be interrupted, and a pinion built in the pinion unit 18. A roller 27 connected coaxially, two cables 28 that transmit a rotational force between the roller 25 and the roller 27, and a guide tube 29 that guides the cable 28 are provided.

  The electromagnetic clutch 26 is energized based on the control of the control means 7b of the EPSECU 7 when the EPSECU 7 is normal. In the energized state, the electromagnetic clutch 26 is in an open state, and between the pulley 23 and the roller 25. No rotational force is transmitted. When the EPSECU 7 is abnormal or when the ignition switch is off, the magnet clutch 26 is engaged and the rotational force is transmitted between the pulley 23 and the roller 25 in the non-excited state.

  In other words, the mechanical connecting portion 6 is configured such that when the EPS ECU 7 is abnormal or the ignition switch is off, the steering angle θ input from the steering wheel 2 is converted to the shaft 3, pulley 14, belt 24, pulley 23, electromagnetic clutch 26, roller. 25, the cable 28, and the roller 27 are transmitted to the pinion built in the pinion unit 18, whereby the rack bar 16 is moved in the vehicle width direction, and manual steering is realized.

  Further, as shown in FIG. 3 in which the portion A of FIG. 2 is enlarged, the steering device 1 of the present embodiment is located at a plurality of positions on the circumference facing the right end surface in the axial direction of the trapezoidal screw nut 8 as a moving member. The end pin 30, the magnet 31 provided on the surface facing the right axial end surface of the trapezoidal screw nut 8 of the right end pin 30, and the annular shape provided at a position facing the magnet 31 on the right axial end surface of the trapezoidal screw nut 8. The magnet 31 and the magnet 32 having different polarities are provided. The right end pin 30 is a restriction member on the right side in the axial direction, the magnet 31 is a restriction member side magnet on the right side in the axial direction, and the magnet 32 is a moving member side magnet on the right side in the axial direction.

  In addition to this, when the steering angle θ is rotated to the right side to be the maximum steering angle + θmax, the shaft is connected via a screw mechanism constituted by the male screw 3a and the female screw 8a by the repulsive force of the magnet 31 and the magnet 32. 3 and the repulsive force of the magnet 32 so that the steering reaction force generated in the steering wheel 2 becomes a magnitude at which the driver judges that the steering wheel 2 cannot be rotated further to the right side, that is, a critical value Tu. Set.

  Further, as shown in FIG. 4 in which the portion B of FIG. 2 is enlarged, the steering device 1 of the present embodiment is located at a plurality of positions on the periphery facing the left end surface in the axial direction of the lock plate 9 as a moving member. The end pin 33, the magnet 34 provided on the surface of the left end pin 33 facing the left end surface in the axial direction of the lock plate 9, and the ring plate provided at a position facing the magnet 34 on the left end surface of the lock plate 9 in the axial direction. The magnet 34 and the magnet 35 having different polarities are provided. The left end pin 33 is a restricting member on the left side in the axial direction, the magnet 34 is a restricting member side magnet on the right side in the axial direction, and the magnet 35 is a moving member side magnet on the right side in the axial direction.

  In addition to this, when the steering angle θ is rotated to the left and is the maximum steering angle −θmax, a repulsive force between the magnet 34 and the magnet 35 causes a screw mechanism constituted by the male screw 3a and the female screw 8a, The magnet 31 and the magnet 32 are adjusted so that the steering reaction force generated in the shaft 3 and the steering wheel 2 has a magnitude that determines that the driver cannot rotate the steering wheel 2 further to the left, that is, a critical value Tu. Set the repulsion.

  In addition, when the trapezoidal screw nut 8 abuts on the right end pin 30 and the lock plate 9 abuts on the left end pin 33, the axial displacement of the trapezoidal screw nut 8 and the lock plate 9 constituting the moving member is restricted. The control value θr of the steering angle θ input by the steering wheel 2 determined by the formula (1) is made larger than the maximum steering angle θmax determined by the maximum turning angle δmax of the wheel 22.

  Further, when the steering angle θ is equal to or greater than the maximum steering angle θmax, the steering angle detection unit 7a of the EPS ECU 7 fixes the detected value of the steering angle θ to the maximum steering angle θmax. In addition, the steering reaction force control means 7c of the EPS ECU 7 uses the steering reaction force generated at the maximum steering angle θmax as the repulsive force between the magnet 31 and the magnet 32 or the steering reaction force generated by the magnet 34 and the magnet 35 at the maximum steering angle θmax. When the steering angle θ is larger than the maximum steering angle θmax, the motor 13 is controlled so as not to generate a steering reaction force.

  FIG. 5 is a schematic diagram showing the relationship between the steering angle θ and the steering reaction force in the steering apparatus 1 of the present embodiment based on comparison with the prior art. As shown in FIG. 5, the steering angle range of the present embodiment is determined by a restriction value θr that is larger than the maximum steering angle θmax, compared to the conventional steering angle range determined by the maximum steering angle θmax of the steering angle θ. Therefore, the steering angle θ, that is, the rotation angle range of the steering wheel 2 becomes wider.

  Also in the prior art, if the steer-by-wire type is the same as the steering device 1 of the present embodiment, the steering of the EPS ECU 7 is such that the steering reaction force increases in a quadratic curve as the steering angle θ increases. Although the motor 13 is controlled based on the control of the reaction force control means 7c, in addition to this in the steering device 1 of the present embodiment, the steering reaction force based on the repulsive force of the magnet 31 and the magnet 32 is added in the right steering. In left steering, a steering reaction force based on the repulsive force of the magnet 34 and the magnet 35 is generated. Therefore, in the range where the steering angle θ exceeds the maximum steering angle θmax, the steering reaction force by the steering reaction force control means 7c is not generated. The steering reaction force based only on the repulsive force between the magnet 31 and the magnet 32 or the repulsive force between the magnet 34 and the magnet 35 is generated.

  According to the steering device 1 of the present embodiment described above, the following operational effects can be obtained. That is, in the case where the steering angle θ is the maximum steering angle θmax, the shaft 3 and the shaft 3 through the screw mechanism constituted by the male screw 3a and the female screw 8a by the repulsive force of the magnet 31 and the magnet 32 or the magnet 34 and the magnet 35. If the repulsive force is set so that the steering reaction force generated in the steering wheel 2 has a magnitude that determines that the driver cannot rotate the steering wheel 2 any more, that is, a critical value Tu, the steering reaction force Since when the driver reaches the critical value Tu, it can be expected that the driver will notice it and stop further steering, so the driver can be encouraged to avoid further rotation of the steering wheel 2.

  Further, after the steering angle θ exceeds the maximum steering angle θmax and the steering reaction force becomes equal to or greater than the critical value Tu, the trapezoidal screw nut 8 comes into contact with the left end surface in the axial direction of the right end pin 30 for right steering. In the case of left steering, the lock plate 9 comes into contact with the right end surface of the left end pin 33 in the axial direction, and the axial displacement of the trapezoidal screw nut 8 and the lock plate 9 constituting the moving member can be mechanically restricted.

  Accordingly, after the right end pin 30 restricts the axial displacement of the trapezoidal screw nut 8 in the axial direction, the driver further rotates the steering wheel 2 to the right, and the shaft is fitted to the female screw 8a of the trapezoidal screw nut 8 as shown in FIG. It is possible to prevent the driver from inputting the steering force Tg that the third male screw 3a bites through the steering wheel 2 and the male screw 3a biting into the female screw 8a.

  Similarly, after the right end axial displacement of the lock plate 9 is restricted by the left end pin 33, the driver further rotates the steering wheel 2 counterclockwise so that the male screw 3 a of the shaft 3 is engaged with the female screw 8 a of the trapezoidal screw nut 8. Can be prevented.

  That is, it is possible to prevent the male screw 3a of the shaft 3 from being bitten by an excessive force with respect to the female screw 8a of the trapezoidal screw nut 8, and to remove the biting from the once bited state to a normal state. Since the returning operation can be avoided, it is possible to prevent the occurrence of vibrations due to overcoming or sliding of the tooth surfaces of the female screw 8a and the male screw 3a during steering, and a better steering feeling for the driver. Can be secured.

  At the same time, when the steering angle θ input by the driver through the steering wheel 2 is the maximum steering angle + θmax on the right side, the trapezoidal screw nut 8 can be prevented from contacting the right end pin 30 and the driver can When the steering angle θ input by the steering wheel 2 is the left maximum steering angle −θmax, the lock plate 9 can be prevented from contacting the left end pin 33.

  Thus, the steering device 1 using the magnet 31, the magnet 32, the magnet 34, and the magnet 35 of the present embodiment can be configured while ensuring the maximum steering angle θmax necessary for turning.

  Further, in the steering device 1, the EPS ECU 7 is provided with a steering angle detection means 7a for detecting the steering angle θ, and when the steering angle θ is equal to or larger than the maximum steering angle θmax, the detected value of the steering angle θ is set to the maximum steering angle θmax. By fixing to the following, the following effects can be obtained.

  That is, although the steering angle θ is the maximum steering angle θmax, the driver steers a larger steering angle θ against the repulsive force of the magnet 31 and the magnet 32 or the repulsive force of the magnet 34 and the magnet 35. In the case of input to the wheel 2, the steering angle detection means 7a fixes the detected value of the steering angle θ to the maximum steering angle θmax, so that the timing at which the driver determines that the steering wheel 2 cannot be rotated any more is delayed, or Even when the determination is incorrect, the detected value of the steering angle θ can be prevented from exceeding the maximum steering angle θmax.

  As a result, it is possible to avoid the steering force generating unit 17 from generating a steering force that exceeds the maximum steering angle δmax in the steering unit 1, particularly in the steering unit 5, and to stabilize the control. .

  Furthermore, in the steering device 1, the EPS ECU 7 is provided with a steering reaction force control means 7c that generates a steering reaction force according to the steering angle θ, and the steering reaction force generated by the steering reaction force control means 7c at the maximum steering angle θmax is When the maximum steering angle θmax is the same as the steering reaction force generated by the repulsive force of the magnet 31 and the magnet 32 or the repulsive force of the magnet 34 and the magnet 35, and the steering angle θ is larger than the maximum steering angle θmax, the steering reaction force control means By controlling the motor 13 of the steering unit 4 so that the steering reaction force is not generated by 7c, the following operational effects can be obtained.

  That is, like the steering device 1 of the present embodiment, in particular, the steering unit 5 that steers the wheel and the steering unit 4 including the front shaft 3 are not mechanically connected when the EPSECU 7 is normal. The steer-by-wire type includes a steering reaction force control means 7c for simulating a steering reaction force from the wheel 22 and a motor 13 controlled by the steering reaction force control means 7c. The continuity between the steering reaction force generated by 7c and the steering reaction force generated by the repulsive force of the magnet 31 and the magnet 32 or the magnet 34 and the magnet 35 via the screw mechanism constituted by the male screw 3a and the female screw 8a is ensured. Thus, a good steering feeling can be ensured.

  Further, when the repulsive force between the magnet 31 and the magnet 32 and the repulsive force between the magnet 34 and the magnet 35 can be secured sufficiently large, when the steering angle θ exceeds the maximum steering angle θmax, it acts on the steering wheel 2 and the shaft 3. The steering reaction force to be obtained is a combined force of the steering reaction force due to the repulsive force between the magnet 31 and the magnet 32 or the repulsive force between the magnet 34 and the magnet 35 and the steering reaction force based on the control of the steering reaction force control means 6a. It can prevent becoming excessive.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions are made to the above-described embodiments without departing from the scope of the present invention. be able to.

  For example, the installation form of the magnet 32 is not limited to being provided in accordance with the axial end surface of the moving member as shown in the above-described embodiment, but as shown in FIG. 6 with respect to the axial end surface of the trapezoidal screw nut 8. It is also possible to provide a recess in the axial direction. According to this, by providing the magnet 31 and the magnet 32, it is possible to prevent the axial length of the housing 11 from increasing. The same applies to the magnet 35, and the magnet 35 can be provided so as to be recessed with respect to the axial end surface of the lock plate 9.

  The threshold value Tu used as a threshold by which the steering reaction force generated in the shaft 3 and the steering wheel 2 determines that the driver cannot further rotate the steering wheel 2 to the right side is determined by a plurality of drivers. It can be obtained statistically by investigating the sense, or can be obtained by calculation by multiplying the steering force Tg at which biting occurs by a predetermined safety factor.

  In the above-described embodiment, when the steering angle θ is equal to or less than the maximum steering angle θmax with the maximum steering angle θmax as a boundary, the steering reaction force control means 7c of the EPS ECU 7 controls the motor 13 to generate the steering reaction force. When the steering angle θ exceeds the maximum steering angle θmax, a steering reaction force is generated based on the repulsive force of the magnet 31, the magnet 32, the magnet 34, and the magnet 35, and the steering reaction force and the steering angle θ are Although the relationship is as shown in FIG. 5, this relationship is merely an example, and it depends on the steering reaction force by the steering reaction force control means 7 c and the repulsive force of the magnet 31 and the magnet 32 and the magnet 34 and the magnet 35. A steering reaction force based thereon may be generated at the same time.

  The present invention relates to a vehicle steering device, and can provide a steering device capable of ensuring a good steering feeling with a relatively simple configuration and minor changes. It is useful when applied to steering devices for various vehicles such as buses.

It is a mimetic diagram showing one embodiment of a steering device concerning the present invention. It is a mimetic diagram showing one embodiment of a steering device concerning the present invention. It is a mimetic diagram showing one embodiment of a steering device concerning the present invention. It is a mimetic diagram showing one embodiment of a steering device concerning the present invention. It is a mimetic diagram showing one embodiment of a steering device concerning the present invention. It is a mimetic diagram showing one embodiment of a steering device concerning the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Steering device 2 Steering wheel 3 Shaft 3a Male screw 4 Steering part 5 Steering part 6 Mechanical connection part 7 EPSECU
7a Steering angle detection means 7b Control means 7c Steering reaction force control means 8 Trapezoidal screw nut 8a Female screw 9 Lock plate 10 Guide shaft 11 Housing 12 Worm gear 13 Motor 14 Pulley 15 Steering angle sensor 16 Rack bar 17 Steering force generator 18 Pinion part 19 tie rod 20 knuckle arm 21 knuckle 22 wheel 23 pulley 24 belt 25 roller 26 electromagnetic clutch 27 roller 28 cable 29 guide tube 30 right end pin 31 magnet 32 magnet 33 left end pin 34 magnet 35 magnet

Claims (5)

  An input shaft for transmitting a steering angle input to the steered wheels, conversion means for converting the steering angle of the input shaft into axial displacement of the input shaft, and a moving member moved in the axial direction by the conversion means A regulating member positioned opposite to the axial end surface of the moving member, a regulating member-side magnet provided on a surface of the regulating member facing the axial end surface of the moving member, and the axial direction of the moving member A steering apparatus comprising: a moving member side magnet having a polarity different from that of the restricting member side magnet, provided at a position facing an end surface of the restricting member side magnet.   2. The restriction value of the steering angle determined by restricting axial displacement of the moving member by the restricting member is set to be larger than a maximum steering angle determined by a maximum turning angle of a wheel. The steering apparatus as described in.   Steering angle detection means for detecting the steering angle is provided, and when the steering angle is equal to or greater than the maximum steering angle, the steering angle detection means fixes the detected value of the steering angle to the maximum steering angle. The steering device according to claim 2.   Steering reaction force control means for generating a steering reaction force corresponding to the steering angle is provided, and the steering reaction force generated by the steering reaction force control means at the maximum steering angle is reduced to the restriction member side magnet at the maximum steering angle. The steering device according to claim 3, wherein the steering reaction force is the same as a steering reaction force generated by a repulsive force between the moving member side magnet and the moving member side magnet.   The steering apparatus according to claim 4, wherein the steering reaction force control means does not generate the steering reaction force when the steering angle is larger than the maximum steering angle.

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