JP4972424B2 - Vehicle steering system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for miniaturizing an expensive turning power motor in a SBW (steer-by-wire) type vehicle steering device. <P>SOLUTION: A controller 61 of the SBW type vehicle steering device 10 controls a connecting mechanism 50 to mechanically connect a steering mechanism 20 and a turning mechanism 30, and controls driving of the turning power motor 45 and reaction force motor 24 to perform a control for turning steered wheels 35, when a steering wheel 21 is operated when vehicle speed is around zero. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a technology for improving a steer-by-wire vehicle steering apparatus.

  2. Description of the Related Art Conventionally, as a general vehicle steering apparatus, a structure in which a steering mechanism is connected to a steering wheel and wheels are steered via the steering mechanism by a steering force of the steering wheel is known.

In recent years, the steering mechanism is mechanically separated from the steering wheel, and a steering actuator (steering power motor) generates steering power according to the steering amount, and this steering power is used as the steering mechanism. A steer-by-wire (steer-by-wire, hereinafter abbreviated as “SBW”) vehicle steering device is known (see, for example, Patent Document 1).
JP-A-2005-29016

In such a vehicle steering device, the control device controls the steering power motor, so that the characteristic of the ratio of the steering angle of the wheel to the steering amount (operation angle) of the steering wheel, that is, the steering characteristic is automatically set. Can be set automatically.
Here, in the conventional SBW-type vehicle steering device, the steering angle ratio is the largest when the vehicle speed is 0, and the steering characteristics are set so that the steering angle ratio decreases as the vehicle speed increases. . As a result, the turning angle of the wheel is increased with respect to the steering angle of the steering wheel at low vehicle speeds, and the turning ability can be improved. The turning angle was reduced and the stability of the vehicle was improved.

  However, in general, in steering at a vehicle speed of 0 (when the vehicle is stopped), the wheel does not rotate, and the vehicle is steered on the spot. Therefore, the maximum power for steering is required for the steering. In particular, in a conventional SBW-type vehicle steering device that achieves the maximum steering angle ratio at a vehicle speed of 0, the steering angle of the wheel is the maximum with respect to the steering angle with respect to the steering wheel at the time of vehicle speed of 0. The motor is required to have the maximum speed for turning the wheel, and the enlargement of the turning power motor cannot be avoided. Here, the steering power motor is expensive, and is required to be small in size because it is disposed in a narrow space of the vehicle.

  Accordingly, an object of the present invention has been made in view of the above-described problems, and an object of the present invention is to provide a technique capable of downsizing an expensive steered power motor in an SBW-type vehicle steering apparatus. .

The present invention proposes the following matters in order to solve the above problems.
(1) A steering mechanism (for example, equivalent to the steering mechanism 20 in FIG. 1) provided with a steering wheel (for example, equivalent to the steering wheel 21 in FIG. 1) and a steering power motor (for example, the steering power motor 45 in FIG. 1). The steering wheel operation amount is detected by a steering angle sensor in a state in which mechanical connection with a steering mechanism (for example, the steering mechanism 30 in FIG. 1) provided with is disconnected, and the detected value is converted into an electric signal. Then, based on the electric signal, the steering power motor is driven to steer the wheel, and the reaction force motor connected to the steering wheel is driven according to the operation amount and the steered amount to drive the steering wheel. In a vehicle steering apparatus that applies a steering reaction force, a coupling mechanism (for example, equivalent to the coupling mechanism 50 in FIG. 1) that can mechanically connect the steering mechanism and the steering mechanism, and the steering power And a control means (for example, corresponding to the control unit 61 in FIG. 1) for controlling the driving of the reaction force motor and the coupling mechanism. When operated, the coupling mechanism is controlled, the steering mechanism and the steering mechanism are mechanically connected, and the wheels are steered by controlling the driving of the steering power motor and the reaction force motor. A vehicle steering apparatus is proposed.

According to the present invention, when the steering wheel is steered when the vehicle speed is near zero, the steering mechanism and the steering mechanism are connected by the connecting mechanism, and the driving of the steering power motor and the reaction force motor is controlled to control the wheels. Steer.
As a result, when the vehicle is steered in the vicinity of 0, the wheels can be steered using the reaction force motor in addition to the steered power motor, so that the output of the steered power motor can be suppressed.

  (2) The present invention relates to the vehicle steering apparatus according to (1), wherein the coupling mechanism is a speed change mechanism (for example, equivalent to the speed change gear mechanism 70 of FIG. 5) that changes the output of the reaction force motor, and the steering mechanism. And a coupling clutch (for example, equivalent to the clutch mechanism 56 in FIG. 5) that mechanically connects the steering mechanism and the control means when the steering wheel is operated when the vehicle speed is near zero The steering power motor is controlled to steer the wheels, the coupling clutch is controlled, the steering mechanism and the steering mechanism are mechanically connected, and the output of the reaction force motor is controlled. A vehicle steering apparatus has been proposed in which the wheels are steered by being shifted by the speed change mechanism.

According to this invention, when the steering wheel is steered when the vehicle speed is near zero, the steering mechanism and the steering mechanism are connected, and the wheels are steered by controlling the driving of the steering power motor and the reaction force motor. However, the output of the reaction force motor at this time is made the optimum output as the steering output by the speed change mechanism.
Thereby, the output of the turning power motor can be suppressed to a lower level when the vehicle speed is around zero.

  According to the present invention, when the steering wheel is steered when the vehicle speed is near zero, the steering mechanism and the steering mechanism are connected by the connection mechanism, and the reaction force motor is used in addition to the steering power motor to rotate the wheels. By steering, the output of the steered power motor can be suppressed, and the steered power motor can be reduced in size.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Note that the constituent elements in the present embodiment can be appropriately replaced with existing constituent elements, and various variations including combinations with other existing constituent elements are possible. Therefore, the description of the present embodiment does not limit the contents of the invention described in the claims.

<Configuration of Vehicle Steering Device of First Embodiment>
The configuration of the vehicle steering apparatus 10 according to the first embodiment of the present invention will be described with reference to FIG.
The vehicle steering device 10 mechanically separates the steering mechanism 30 from the steering wheel 21 as a steering member, and generates steering power from the steering actuator 38 according to the steering amount of the steering wheel 21. This is a so-called steer-by-wire (SBW) type vehicle steering apparatus in which the steering mechanism 30 steers the left and right steered wheels 35, 35 by transmitting the steering power to the steering mechanism 30. .

  The steering mechanism 20 of the vehicle steering device 10 includes a steering wheel 21 gripped by the driver, a steering shaft 22 connected to the steering wheel 21, a steering angle sensor 23 that detects the steering angle of the steering wheel 21, and the steering wheel 21. A reaction force motor 24 for generating a steering reaction force (reaction torque) against the motor, a motor rotation angle sensor 25 for detecting the rotation angle of the reaction force motor 24, and a reaction force torque for detecting a reaction force torque acting on the steering shaft 22. The sensor 32 includes a reaction force transmission mechanism 26 that transmits a steering reaction force to the steering shaft 22.

  Here, the reaction force motor 24 is an electric motor, and the reaction force transmission mechanism 26 is a worm 27 provided on the motor shaft of the reaction force motor 24 and a worm wheel 28 coupled to the steering shaft 22 and meshed with the worm 27. A worm gear mechanism, that is, a booster mechanism. The steering reaction force is an operation resistance added to the steering wheel 21 in the rotational direction.

  The turning mechanism 30 includes an input shaft 31 for inputting a steering force of the steering shaft 22, a rack shaft 34 connected to the input shaft 31 via a rack and pinion mechanism 33, and left and right turning wheels at both ends of the rack shaft 34. Tie rods 36, 36 and knuckles 37, 37 that connect 35, 35 (for example, front wheels), a steering actuator 38 that adds steering power to the input shaft 31, and an input shaft that detects the rotation angle of the input shaft 31. The rotation angle sensor 41 and a rack shaft position sensor 42 for detecting the position of the rack shaft 34 are configured.

  The rack and pinion mechanism 33 includes a pinion 43 formed on the input shaft 31 and a rack 44 formed on the rack shaft 34. The steering actuator 38 includes a steering power motor 45 that generates steering power and a steering power transmission mechanism 46 that transmits the steering power to the input shaft 31. Here, the turning power motor 45 is an electric motor. The turning power transmission mechanism 46 includes a worm 47 provided on the motor shaft of the turning power motor 45 and a worm gear 48 that is coupled to the input shaft 31 and meshed with the worm 47, that is, a boosting mechanism. It is.

  As described above, the vehicle steering apparatus 10 is an end take-off type steering apparatus in which the steering torque is extracted from both ends of the rack shaft 34. Further, the vehicle steering device 10 is configured such that a steering shaft 22 provided on the steering wheel 21 and an input shaft 31 provided on the steering mechanism 30 are connected by a connecting mechanism 50 including a clutch mechanism 51. is there. Specifically, the steering input side of the clutch mechanism 51 is connected to the steering shaft 22 via the first universal shaft joint 52, and the steering output side of the clutch mechanism 51 is connected to the input shaft 31 via the second universal shaft joint 53. Connected.

  The clutch mechanism 51 is an open-type clutch mechanism when energized, which is in an open state during control and is in a connected state when the connection signal Cn of the control unit 61 or the clutch power supply is cut off. The clutch mechanism 51 includes a connection rod 54 and a connection detection sensor 55. The connection detection sensor 55 is a limit switch that detects that the connection rod 54 is pushed by the tip of the connection rod 54 when the connection rod 54 is inserted into the rod connection hole and connected. The connection detection sensor 55 issues a connection completion signal when the connection rod 54 is connected to the rod connection hole, and issues an opening signal when the connection rod 54 is released from the rod connection hole and the connection is released.

  The control unit 61 receives detection signals from the steering angle sensor 23, the motor rotation angle sensor 25, the reaction force torque sensor 32, the input shaft rotation angle sensor 41, and the rack shaft position sensor 42, and detects the vehicle speed. Receiving detection signals from the sensor 62, the yaw rate sensor 63 for detecting the yaw angular velocity (the angular velocity of the yaw motion), the acceleration sensor 64 for detecting the acceleration of the vehicle, and other various sensors 65, the reaction force motor 24, the turning power motor are received. 45 and a control signal to the clutch mechanism 51.

  The controller 61 sets a target steering reaction force based on the vehicle speed signal from the vehicle speed sensor 62, the steering angle signal from the steering angle sensor 23, and the like. Then, the control unit 61 controls the reaction force motor 24 so that the output value of the reaction force torque sensor 32, that is, the actual steering reaction force coincides with the target steering reaction force. As a result, a steering reaction force in the direction opposite to the operation direction of the steering wheel 21 by the driver is applied to the steering wheel 21, so that the driver mechanically connects the steering wheel 21 and the steered wheels 35 and 35. It is possible to obtain a steering feeling as if it were.

  Here, the control unit 61 automatically sets the steering reaction force according to the operation of the steering wheel 21 and the turning amount of the steered wheels 35 and 35 by controlling the reaction force motor 24, and the steering reaction force. Can be added to the steering wheel 21 and controlled as in the following (1) to (4).

  (1) When the worm wheel 28 is rotated by the reaction force motor 24 in the direction opposite to the steering direction of the steering wheel 21, the steering force of the steering wheel 21 is canceled by the steering reaction force of the reaction force motor 24. work. For this reason, when the steering wheel 21 is steered, a steering force that is larger by the steering reaction force is required.

  (2) When the worm wheel 28 is rotated in the same direction as the steering direction of the steering wheel 21 by the reaction force motor 24, the action of adding the steering reaction force of the reaction force motor 24 to the steering force of the steering wheel 21 works. . For this reason, when the steering wheel 21 is steered, a steering force that is as small as the steering reaction force is sufficient.

  (3) When the steering wheel 21 is held at an arbitrary angle in a stopped state, the reaction force motor 24 applies a torque commensurate with the direction and force in which the steered wheels 35 and 35 return to the straight traveling state to the worm wheel 28. A holding force is generated by giving.

  (4) When the steering wheel 21 is subsequently returned, a return force (steering reaction force) corresponding to so-called self-aligning torque that automatically returns the steering wheel 21 to the neutral position of the steering wheel 21 is a reaction force motor. 24 is transmitted to the worm wheel 28.

  Further, the control unit 61 automatically sets the characteristics of the angle ratio of the steered wheels 35 and 35 to the steering angle of the steering wheel 21, that is, the steering characteristics, by controlling the steered power motor 45. can do. That is, since the steering mechanism 30 is mechanically separated from the steering wheel 21 as described above, the correspondence between the steering angle of the steering wheel 21 and the operation amount of the steering actuator 38 is not subject to mechanical restrictions. Can be set. As a result, the steering characteristics can be flexibly set according to the traveling state of the vehicle, such as the vehicle speed, the degree of turning of the vehicle, and the presence or absence of acceleration or deceleration. Therefore, the handling stability of the vehicle can be enhanced and the danger avoidance capability can be enhanced.

  Further, the control unit 61 issues a connection signal Cn to the clutch mechanism 51 or stops the control and shuts off the power source of the clutch mechanism 51 so that the clutch mechanism 51 enters a connected state. As a result, when the electrical connection between the steering mechanism 20 and the steered mechanism 30 is released due to some factor, the control unit 61 issues a connection signal Cn or the control is stopped. The mechanism 51 is connected. That is, when the electrical connection is released, for example, the steering mechanism 20 and the steering mechanism 30 can be connected to automatically switch to the backup system. On the other hand, in the normal state, the clutch mechanism 51 can be opened, and the steering characteristics can be flexibly set according to the traveling state of the vehicle.

<Steering wheel steering control>
Next, turning control of the turning wheels 35 and 35 will be described with reference to FIG.
FIG. 2 is a turning control block diagram of the turning wheels 35 and 35 in the vehicle steering apparatus 10 according to the present embodiment. In addition, this block diagram shows the steering control of the steered wheels 35 and 35 in a state where the steering mechanism 20 and the steering mechanism 30 are not connected (normal state).

  As shown in FIG. 2, the steering control block of the steered wheels 35 and 35 in the normal state includes a steering angle sensor 23, a vehicle speed sensor 62, a control unit 61, and a steered power motor 45.

  Here, the steering angle sensor 23 detects the rotation angle of the steering wheel 21, and the vehicle speed sensor 62 detects the traveling speed of the vehicle. The controller 61 sets a target turning angle corresponding to the steering angle based on the steering characteristics (steering angle ratio (steering angle / steering angle)) according to the vehicle speed. And the control part 61 controls the turning power motor 45 so that this target turning angle and the actual turning angle of the turning wheels 35 and 35 may correspond. The steered power motor 45 steers the steered wheels 35 and 35 under the control of the control unit 61.

  Here, in the vehicle steering device 10, the target turning angle is set so that the turning angle of the turning wheels 35 and 35 is larger than the steering angle of the steering wheel 21 at low vehicle speeds. At high vehicle speeds, the target turning angle is set such that the turning angles of the turning wheels 35 and 35 are smaller than the steering angle of the steering wheel 21. As a result, the turning ability can be enhanced at low vehicle speeds, and the stability of the vehicle can be enhanced at high vehicle speeds.

<Rearing control at stationary>
Next, steering control of the steered wheels 35 and 35 at the time of stationary (steering when the vehicle is stopped) in the vehicle steering apparatus 10 according to the first embodiment will be described with reference to FIGS. 3 and 4.
FIG. 3 is a steering control block diagram of the steered wheels 35 and 35 at the time of stationary. FIG. 4 is a steering control flow of the steered wheels 35 and 35 at the time of stationary.

As shown in FIG. 3, the steering control block of the steered wheels 35 and 35 at the time of stationary is a rudder angle sensor 23, a vehicle speed sensor 62, a control unit 61, a steered power motor 45, and a reaction force motor. 24 and a clutch mechanism 51.
That is, in the steering control of the steered wheels 35 and 35 at the time of stationary, the steered wheels 35 and 35 are steered by using the reaction force motor 24 and the clutch mechanism 51 that are not used for steering in a normal state. There is a feature.

  Here, the steering angle sensor 23 detects the rotation angle of the steering wheel 21, and the vehicle speed sensor 62 detects the traveling speed of the vehicle. The control unit 61 sets a target turning angle corresponding to the steering angle based on the steering characteristics according to the vehicle speed, and issues a Cn signal to the clutch mechanism 51. The clutch mechanism 51 that has received the Cn signal connects the steering mechanism 20 and the steering mechanism 30 by being controlled from the released state to the connected state. Then, the control unit 61 controls the steered power motor 45 and the reaction force motor 24 so that the steering torque of the steering wheel 21 matches the set target torque. That is, the control unit 61 controls the reaction force motor 24 so that the worm wheel 28 rotates in the same direction as the steering direction of the steering wheel 21. The steered power motor 45 and the reaction force motor 24 steer the steered wheels 35 and 35 according to the control of the control unit 61.

Next, the steering control process at the time of stationary will be described with reference to FIG.
First, the steering angle sensor 23 detects the rotation angle of the steering wheel 21, and the vehicle speed sensor 62 detects the traveling speed of the vehicle (step S101). When the detected value of the vehicle speed sensor 62 is zero, that is, when the vehicle is stopped and there is an output from the rudder angle sensor 23, the control unit 61 determines that the operation mode is when the steering wheel 21 is stationary. (“Yes” in step S102), a Cn signal is issued to the clutch mechanism 51 (step S103).

  When the Cn signal is received, the clutch mechanism 51 is controlled from the released state to the connected state. When the clutch mechanism 51 is controlled to be connected and the connection detection sensor 55 detects that the connection rod 54 is connected to the rod connection hole, the connection detection sensor 55 issues a connection completion signal to the control unit 61. Upon receiving the connection completion signal, the control unit 61 determines that the clutch mechanism 51 is connected (“YES” in step S104), and drives the reaction force motor 24 and the turning power motor 45 to turn the wheels. (Step S105).

  As described above, in the vehicle steering apparatus 10 according to the present embodiment, the steering mechanism 20 and the steering mechanism 30 are mechanically connected by connecting the clutch mechanism 51 when the vehicle is stationary, and the steering power motor 45 and Since the wheels are steered by controlling the driving of the reaction force motor 24, the output of the steered power motor 45 at the time of stationary can be suppressed, and the steered power motor 45 can be downsized.

Here, when the steering mechanism 20 and the steering mechanism 30 are mechanically coupled, the steering wheel 21 and the steered wheels 35 and 35 are coupled. A steering reaction force is generated directly from the wheels 35. Therefore, the turning power motor 45 can be reduced in size by using the reaction force motor 24 that is not necessary when the steering mechanism 20 and the turning mechanism 30 are connected.
Therefore, in the vehicle steering device 10 according to the present embodiment, it is not necessary to use a new device, and the turning power motor 45 can be reduced in size without cost.

<Configuration of Vehicle Steering Device of Second Embodiment>
The configuration of the vehicle steering apparatus 10A according to the second embodiment of the present invention will be described with reference to FIG.
In the present embodiment, the configuration of a connection mechanism 50A that connects the steering mechanism 20 and the steering mechanism 30 is different from that of the first embodiment.

  That is, the connection mechanism 50 </ b> A includes the clutch mechanism 51, the clutch mechanism 56, the transmission gear mechanism 70, the first connection shaft 80, and the second connection shaft 81.

  Here, the transmission gear mechanism 70 includes a first gear 71, a second gear 72, a third gear 73 (transmission gear) meshed with the first gear 71, and a fourth gear meshed with the second gear 72. 74 (transmission gear).

The first connecting shaft 80 is connected to the steering shaft 22 via the first universal shaft joint 52, and is connected to the input shaft 31 via the second universal shaft joint 53.
The first gear 71 is coupled to the first universal shaft joint 52 side of the first connecting shaft 80, and the second gear 72 is coupled to the second universal shaft joint 53 side of the first connecting shaft 80. The clutch mechanism 51 is coupled between the first gear 71 and the second gear 72 of the first connecting shaft 80.

The third gear 73 and the fourth gear 74 are coupled to the second connecting shaft 81. The clutch mechanism 56 is coupled between the third gear 73 and the fourth gear 74 of the second connecting shaft 81.
The second connecting shaft 81 is connected to the steering shaft 22 via the first gear 71 meshed with the third gear 73 and is connected to the input shaft 31 via the second gear 72 meshed with the fourth gear 74. The

The clutch mechanism 51 is a normally open clutch mechanism that includes a connecting rod 54 and a connection detection sensor 55. The clutch mechanism 51 is a clutch mechanism that is in a connected state when the electrical connection between the steering mechanism 20 and the steering mechanism 30 is released.
The clutch mechanism 56 is a normally open clutch mechanism including a connecting rod 57 and a connection detection sensor 58. The clutch mechanism 56 is a clutch mechanism that is in a connected state when stationary.

  That is, the vehicle steering apparatus 10A of the second embodiment is provided with a backup clutch mechanism 51 and a stationary clutch mechanism 56 in order to connect the steering mechanism 20 and the steering mechanism 30. .

  Here, the third gear 73 is a transmission gear, and the number of gears of the third gear 73 is configured to be different from the number of gears of the first gear 71. Therefore, the rotation of the first gear 71 accompanying the rotation of the steering shaft 22 is shifted by the third gear 73 and transmitted to the second connecting shaft 81. Then, the rotation of the steering shaft 22 that has been transmitted to the second connecting shaft 81 is transmitted to the input shaft 31 via the fourth gear 74 and the second gear 72 when the clutch mechanism 56 is connected. The

<Rearing control at stationary>
Next, steering control of the steered wheels 35 and 35 at the time of stationary in the vehicle steering apparatus 10A of the second embodiment will be described using FIG. 6 and FIG.
FIG. 6 is a turning control block diagram of the turning wheels 35 and 35 at the time of stationary. FIG. 7 is a steering control flow of the steering wheels 35 and 35 at the time of stationary.

As shown in FIG. 6, the steering control block of the steered wheels 35, 35 at the time of stationary is a rudder angle sensor 23, a vehicle speed sensor 62, a control unit 61, a steered power motor 45, and a reaction force motor. 24, a transmission gear mechanism 70, and a clutch mechanism 56.
That is, in the steering control of the steered wheels 35 and 35 at the time of stationary, the steered wheels are used by using the reaction force motor 24, the transmission gear mechanism 70, and the clutch mechanism 56 that are not used in the normal state (see FIG. 2). It is characterized in that 35 and 35 are steered.

  Here, the steering angle sensor 23 detects the rotation angle of the steering wheel 21, and the vehicle speed sensor 62 detects the traveling speed of the vehicle. The control unit 61 sets a target turning angle corresponding to the steering angle based on the steering characteristics corresponding to the vehicle speed, and issues a Cn signal to the clutch mechanism 56. The clutch mechanism 56 that has received the Cn signal connects the steering mechanism 20 and the steered mechanism 30 by being controlled from the released state to the connected state. And the control part 61 controls the turning power motor 45 and the reaction force motor 24 so that the set target turning torque and actual turning torque may correspond. That is, the control unit 61 controls the reaction force motor 24 so that the worm wheel 28 rotates in the same direction as the steering direction of the steering wheel 21. The steered power motor 45 and the reaction force motor 24 steer the steered wheels 35 and 35 according to the control of the control unit 61. At this time, the rotation (output) generated by the reaction motor 24 is converted to an optimum speed ratio by the transmission gear mechanism 70 and transmitted to the input shaft 31.

Next, the steering control process at the time of stationary will be described with reference to FIG.
First, the steering angle sensor 23 detects the rotation angle of the steering wheel 21, and the vehicle speed sensor 62 detects the traveling speed of the vehicle (step S201). When the detected value of the vehicle speed sensor 62 is zero, that is, when the vehicle is stopped and there is an output from the rudder angle sensor 23, the control unit 61 determines that the operation mode is when the steering wheel 21 is stationary. (“Yes” in step S202), a Cn signal is generated to the stationary clutch mechanism 56 (step S203).

  When the Cn signal is received, the clutch mechanism 56 is controlled from the released state to the connected state. When the clutch mechanism 56 is controlled to be connected and the connection detection sensor 58 detects that the connection rod 57 is connected to the rod connection hole, the connection detection sensor 58 issues a connection completion signal to the control unit 61. Upon receipt of the connection completion signal, the controller 61 determines that the clutch mechanism 56 has been connected (“YES” in step S204), and drives the reaction force motor 24 and the turning power motor 45 to turn the wheels. (Step S205). At this time, the rotation (output) of the reaction force motor 24 is shifted by the transmission gear mechanism 70 and transmitted.

  As described above, in the vehicle steering apparatus 10A according to the present embodiment, the steering mechanism 20 and the steering mechanism 30 are mechanically connected to each other by rotating the stationary clutch mechanism 56 during the stationary operation. The wheels are steered by controlling the driving of the rudder power motor 45 and the reaction force motor 24. Therefore, the output of the turning power motor 45 at the time of stationary can be suppressed, and the turning power motor 45 can be reduced in size.

  In particular, since the steering mechanism 20 and the steering mechanism 30 can be connected using the clutch mechanism 56 for the stationary operation separately from the backup clutch mechanism 51, the reduction ratio (speed increasing ratio) suitable for the stationary operation can be obtained. The steering mechanism 20 and the steering mechanism 30 can be connected. Thereby, the output of the reaction force motor 24 at the time of stationary can be transmitted with the optimal reduction ratio (speed increase ratio).

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes a design that does not depart from the gist of the present invention. That is, in the embodiment, the steering mechanism 20 and the steering mechanism 30 are connected at a vehicle speed of 0 (at the time of stationary), and the steering wheels 35 and 35 are steered using the reaction force motor 24. It is not limited to this. For example, not only when the vehicle speed is 0, but when the vehicle speed is near 0, the steering mechanism 20 and the steering mechanism 30 are connected, and the steering wheels 35 and 35 are steered using the reaction force motor 24. It is good as well.

1 is a configuration diagram of a vehicle steering apparatus according to a first embodiment of the present invention. It is a steering control block diagram of the steering wheel of the steering apparatus for vehicles which concerns on the said embodiment. It is a steering control block diagram of the steered wheel at the time of stationary of the vehicle steering device which concerns on the said embodiment. It is a steering control flow of the steering wheel at the time of stationary of the vehicle steering device which concerns on the said embodiment. It is a block diagram of the steering apparatus for vehicles which concerns on 2nd Embodiment of this invention. It is a steering control block diagram of the steered wheel at the time of stationary of the vehicle steering device which concerns on the said embodiment. It is a steering control flow of the steering wheel at the time of stationary of the vehicle steering device which concerns on the said embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Steering device for vehicles, 20 ... Steering mechanism, 21 ... Steering wheel, 23 ... Steering angle sensor, 24 ... Reaction force motor, 30 ... Steering mechanism, 45 ... Steering power motor, 50 ... coupling mechanism, 51 ... clutch mechanism, 61 ... control unit, 62 ... vehicle speed sensor

Claims (1)

A steering mechanism having a steering wheel coupled to a steering shaft, a steering mechanism having a steering power motor for adding steering power to an input shaft connectable to the steering shaft, the steering shaft, and the input shaft A coupling mechanism capable of mechanically coupling the steering mechanism and the steered mechanism by coupling
In a state where the mechanical connection between the steering mechanism and the steering mechanism is disconnected, the operation amount of the steering wheel is detected by a steering angle sensor, the detected value is converted into an electric signal, and the electric signal is based on the electric signal. The steering power motor is driven to steer the wheels, and the reaction force motor connected to the steering wheel via the steering shaft is driven according to the operation amount and the steering amount to steer the reaction force on the steering wheel. In the vehicle steering device that provides
The steering power motor, control means for controlling the driving of the reaction motor and the coupling mechanism comprises a
The coupling mechanism is
A first connection mechanism that transmits an output from the steering shaft to the input shaft when connected;
A second connection mechanism that shifts the output from the steering shaft during transmission and transmits the output to the input shaft;
The control means controls the second connecting mechanism when the steering wheel is operated when the vehicle speed is near zero , and mechanically connects the steering mechanism and the steering mechanism. A vehicle steering apparatus, wherein wheels are steered by controlling driving of the steering power motor and the reaction force motor .

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