JP2008238940A - Vehicular control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the disagreement of a steering angle and a turning angle at starting in a configuration of mechanically separating a steering wheel from a steering gear. <P>SOLUTION: In a vehicular control device 1, a starting state signal generating means 41 generates a starting state signal for a period of time determined by a timer 41A when an ignition switch 43 is ON. During the generation, turning of a tire is prohibited. A second driving signal forming means 42 forms a driving signal and a driving motor 12 makes the steering wheel 2 rotate. When a differential angle of the steering wheel 2 to the turning angle of the tire becomes smaller, the driving signal from the second driving signal forming means 42 is stopped by a command of a differential angle signal comparing means 31 and a steering reaction force is generated from the driving motor 12 according to operation of a driver. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle control device.

  A steer-by-wire vehicle control device has been developed in which a steering wheel and a steering gear for steering a steering wheel are mechanically separated. In this vehicle control device, a sensor for detecting the rotation of the steering wheel is provided, the steering angle of the steering wheel is detected by the sensor, and the steering angle corresponding to this is calculated by the control device. Further, the steering gear is driven so that the steering wheel angle matches the steering angle.

In this type of vehicle control device, a motor is provided so as to apply a reaction force to the steering wheel. When applying the reaction force, the rotation angle of the steering wheel and the vehicle speed are detected, and the target reaction force torque is calculated according to these. Torque corresponding to the target reaction torque is applied to the steering wheel. On the steered wheel side, the motor is steered by servo control (see, for example, Patent Document 1).
JP 2004-291853 A

However, when the steering wheel or the steering wheel is moved with the ignition switch turned off, the steering angle of the steering wheel may be different from the steering angle of the steering wheel. In this case, since the system is started in a state where the steering angle does not coincide with the steering angle, a large reaction force may suddenly occur on the steering wheel.
The present invention has been made in view of such circumstances, and a main object thereof is to provide an appropriate reaction force regardless of the difference between the steering angle and the steering angle.

The invention according to claim 1 of the present invention for solving the above-mentioned problems is a steering shaft rotatably supported on a vehicle body of a vehicle, a steering wheel attached to the steering shaft and rotating together with the steering shaft, and the steering A first counter having a first counter that detects rotation of the shaft and receives the pulse train signal from an encoder that generates a pulse train signal along with the rotation of the steering shaft, counts the pulse train signal, and generates a first count signal. 1 position detection means and a first count signal output from the first counter of the first position detection means is converted into a signal indicating the amount of rotation of the steering wheel, and output as a steering angle signal An angle calculating means and rotating the steering wheel; A drive motor capable of steering, a steered wheel supported to be steerable by a vehicle body of the vehicle, a drive means having an electric motor and changing a steering angle of the steered wheel with respect to the vehicle body of the vehicle, A second counter that detects a change in the steering angle, counts a detection signal supplied from an encoder that generates a detection signal in accordance with a change in the steering angle of the steering wheel, and outputs a second count signal; A second position detection means having a second count signal supplied from the second counter of the second position detection means is converted into a signal indicating a change amount of the steering angle of the steering wheel, Steering angle calculation means for outputting the steering angle signal, and the steering angle signal is supplied from the steering angle calculation means, and the steering angle signal is supplied from the steering angle calculation means, and the steering angle signal and the steering angle are supplied. Compare the angle signal and An angle difference signal calculating means for generating an angle difference signal, and a first drive signal generating means for generating an angle difference signal from the angle difference signal calculating means and generating a drive signal for the drive motor based on the angle difference signal And a start state signal generating means for generating a start state signal only for a predetermined time when the power is turned on, and driving the drive motor so that the difference in steering angle with respect to the steering angle is reduced when the start state signal is generated. The vehicle control device includes a second drive signal generating means for generating a signal.
This vehicle control device causes the steering reaction force to act on the steering wheel based on the angle difference signal by the first drive signal generation means. At the time of starting, the driving motor is driven so that the starting state signal is generated and the angle difference is reduced by the second driving signal generating means. As a result, at the start, the steering wheel is rotated to an angle that matches the steering angle.

According to a second aspect of the present invention, in the vehicle control device according to the first aspect of the present invention, the vehicle control device further includes a prohibition signal generation circuit that stops the steering of the steered wheels when a start state signal is generated.
In this vehicle control device, the prohibition signal generation circuit stops the steering of the steering wheel. As a result, the drive motor is driven so that the steering angle of the steering wheel coincides with the steering angle of the steering wheel in the stopped state.

According to a third aspect of the present invention, in the vehicle control device according to the first or second aspect, the difference between the steering angle with respect to the steering angle and the timer that starts counting upon generation of the start state signal is equal to or less than a predetermined value. If the count value of the timer reaches a predetermined value before the timer reaches, a warning signal generating means for generating a warning signal is provided.
This vehicle control device can start running as long as the driving of the steering wheel is completed before the count value of the timer reaches a predetermined value. When the angle difference between the steering wheel and the steering wheel cannot be reduced, an alarm is issued to inform the driver.

According to a fourth aspect of the present invention, in the vehicle control device according to any one of the first to third aspects, the second drive signal generating means generates only while the start state signal is generated. In other cases, the drive signal is supplied to the drive motor. In other cases, the drive signal generated by the first drive signal generation means is supplied to the drive motor, so that the difference between the actual steering angle and the steering angle is obtained. Drive signal switching means for switching so that the steering reaction force calculated accordingly acts on the steering wheel is provided.
This vehicle control device uses the drive motor to generate a steering reaction force after the driving of the steering wheel is completed.

  According to the present invention, at the time of starting, a start state signal is generated and the drive motor is driven so that the steering angle coincides with the steering angle, so that the driving is performed with a small difference between the steering angle and the steering angle. Can be started, and the progress of the vehicle can be further stabilized.

  As shown in FIGS. 1 and 2, the vehicle control apparatus 1 operates a steering shaft 3 to which a steering wheel 2 as input means operated by a driver is attached, and a steered wheel (hereinafter referred to as a tire) 4. The steering gear 5 to be directed is not mechanically connected, and is electrically connected via the first control device 6 on the steering shaft 3 side and the second control device 7 of the steering gear 5.

  The steering shaft 3 is rotatably supported by a housing 11 fixed to the vehicle body. The housing 11 accommodates a drive motor 12 in which a reduction mechanism is attached to an electric motor, and is coupled to the steering shaft 3 so that the power of the drive motor 12 can be transmitted. Furthermore, a first encoder 13 that outputs a pulse signal according to the rotation of the steering wheel 2 and a second encoder 14 that detects a neutral point of the steering angle of the steering wheel 2 are attached to the housing 11. . The drive motor 12 is connected to the first control device 6 via the drive circuit 16. The drive circuit 16 includes a switching element and the like, and is configured to supply a current from a power source (not shown) to the drive motor 12.

  The first encoder 13 is an incremental rotary encoder. The rotary encoder has a disk (not shown) that rotates together with the steering wheel 2, and two rows of patterns are formed on the disk. Each pattern is composed of, for example, slits having substantially the same width formed at equal intervals in the circumferential direction, and the slit arrangement of the other pattern is set to 1/4 of the slit width in the circumferential direction with respect to the arrangement of the slits of one pattern It is arranged just shifted. Therefore, if the light emitting element and the light receiving element are arranged with the disc interposed therebetween, a signal in which the pulse generation timing is shifted by a quarter period corresponding to each pattern can be obtained. An example of such a pulse signal is shown in FIG. Hereinafter, a first pulse signal generated by one pattern is referred to as an A-phase rotation detection signal Aw, and a second pulse train signal generated by the other pattern is referred to as a B-phase rotation detection signal Bw.

  The second encoder 14 is used as a center position detection sensor that detects a position at which the steering angle is reset. For example, a sensor is used that provides a marker on a disc that has been decelerated so as to rotate once when the steering wheel 2 is rotated within a steerable range, and that outputs a pulse signal when this marker is detected. The marker is provided corresponding to the rotational position of the steering wheel 2 when the tire 4 faces in the straight traveling direction. Since the vehicle is configured such that the tire 4 can be steered by the same amount on the right side and the left side with respect to the straight traveling direction, the rotational position of the steering wheel 2 at this time corresponds to the neutral point of the steerable region. To do. Accordingly, when the driver rotates the steering wheel 2, one neutral point position signal Cw (see FIG. 3) is output as the initial position signal each time the neutral point is reached. The neutral point position signal Cw is a pulse signal having a time width longer than ½ of each cycle of the rotation detection signals Aw and Bw and shorter than each cycle of the rotation detection signals Aw and Bw.

The first control device 6 includes, as first counting means, an up / down determination circuit 21 to which the rotation detection signals Aw and Bw are input, an edge detection circuit 22A to which the rotation detection signal Aw is input, and rotation detection. An edge detection circuit 22B to which the signal Bw is input and an up / down counter 24 as a first counter are included.
The up / down counter 24 is connected to the outputs of the edge detection circuits 22A and 22B via the OR circuit 25, and to the output of the up / down determination circuit 21 and the output of the reset signal shaping means 23. The reset signal shaping unit 23 generates a reset signal that resets the first count signal of the up / down counter 24 when the neutral point position signal Cw is input, and inputs the reset signal to the reset terminal.

  The first count signal output from the up / down counter 24 is connected to the steering angle calculation means 26. The steering angle calculation means 26 searches the steering angle map 27 and calculates the steering angle. The steering angle map 27 has a configuration in which the count value of the up / down counter 24 is associated with the steering angle. The output of the steering angle calculation means 26 is connected to a steering angle signal output circuit 28 and an angle difference signal calculation means 29.

In addition to the actual steering angle, the angle difference signal calculating unit 29 receives a steering angle signal of the second control device 7 via the steering angle signal receiving unit 37. The calculation result of the angle difference between the actual steering angle and the steering angle is input to the steering reaction force calculation means 30 and the angle difference signal comparison means 31 as an output of the angle difference signal calculation means 29.
The steering reaction force calculation means 30 searches the steering reaction force map 38 and calculates the steering reaction force generated by the drive motor 12. The steering reaction force map 38 has a configuration in which an angle difference and a steering reaction force are associated with each other. The magnitude and direction of the steering reaction force are selected so that the steering angle matches the steering angle. The output of the steering reaction force calculation means 30 is connected to the first drive signal generation means 39. The first drive signal generation means 39 receives the steering reaction force signal calculated by the steering reaction force calculation means 30 and generates a drive signal for the drive motor 12. The output of the first drive signal generating means 39 is connected to the drive signal switching means 40. The driving signal switching unit 40 is also connected to a starting state signal generating unit 41 and a second driving signal generating unit 42, and outputs a driving signal to the driving circuit 16.

The starting state signal generating means 41 generates a starting state signal when an ignition switch 43 provided outside the first control device 6 is turned on. The starting state signal generating means 41 has a timer 41A and can output the starting state signal continuously for a predetermined time.
The ignition switch 43 is provided between the power supply 44 and the constant voltage generation circuit 45. The output of the constant voltage generation circuit 45 is supplied to the other and is also connected to the voltage comparison means 46. The voltage comparison means 46 compares the data stored in the memory 47 with the voltage of the constant voltage generation circuit 45 and outputs the comparison result to the starting state signal generation means 41.
The output of the starting state signal generating means 41 is connected to a driving signal switching means 40, a second driving signal generating means 42, an angle difference signal comparing means 31, a timer 48, and a starting state signal output circuit 49. Yes.

The starting state signal output circuit 49 is connected to the second control device 7 and transmits a starting state signal.
The angle difference signal comparison unit 31 is configured to acquire the angle difference signal from the angle difference signal calculation unit 29 when receiving the input of the start state signal and compare it with the data stored in the memory 50. The comparison result is output to the second drive signal generation means 42 and the timer 48.
The drive signal generation unit 42 generates a drive signal at the time of start and outputs it to the drive signal switching unit 40.
The timer 48 starts counting from the input of the start state signal. When the angle difference signal becomes zero, the count value is reset. The count value is output to the alarm signal generating means 51.
The alarm signal generating means 51 is connected to the lamp 52. When the count value exceeds a predetermined value, the lamp 52 is turned on. The lamp 52 is disposed on the instrument panel.

  As shown in FIG. 2, the steering gear 5 includes a steering motor 61 in which a reduction mechanism is attached to an electric motor as driving means, and a rack and pinion mechanism that converts the rotation of the steering motor 61 into a linear motion of a tie rod 63. ing. The tire 4 is connected to both ends of the tie rod 63 via a tie rod 63 and a knuckle arm 64. The steering motor 61 is connected to the second control device 7 via the drive circuit 65. The drive circuit 65 includes a switching element and the like, and is configured to supply a current from a power source (not shown) to the steering motor 61.

The steering motor 61 is provided with a third encoder 66 that detects the steering angle from the rotation of the steering motor 61. The third encoder 66 uses an incremental rotary encoder as described above. From the third encoder 66, an A-phase rotation detection signal Ag, which is a fourth pulse train signal, and a B-phase rotation detection signal Bg, which is a fifth pulse train signal whose pulse generation timing is shifted by ¼ cycle, Is output.
A fourth encoder 67 for detecting the neutral point of the steering angle is attached to the steering gear 5 as a center position detection sensor for detecting the position for resetting the steering angle. The fourth encoder 67 detects the neutral point of the steering angle by detecting the intermediate point between the rack end where the tie rod 63 moves to the right and the rack end where it moves to the left. A marking (not shown) that moves together with 63 is detected, and one neutral point position signal Cg (see FIG. 3) is output as an initial position signal. The neutral point position signal Cg is a pulse signal having a duration that is longer than ½ of each cycle of the rotation detection signals Ag and Bg and shorter than each cycle of the rotation detection signals Ag and Bg.

The second control device 7 includes, as second counting means, an up / down determination circuit 71 to which the rotation detection signals Ag and Bg are input, an edge detection circuit 72A to which the rotation detection signal Ag is input, and rotation detection. An edge detection circuit 72B to which the signal Bg is input and an up / down counter 74 as a second counter are included.
The up / down counter 74 is connected to the outputs of the edge detection circuits 72A and 72B via the OR circuit 75, and to the output of the up / down determination circuit 71 and the output of the reset signal shaping means 76. The reset signal shaping means 76 generates a reset signal for resetting the second count signal of the up / down counter 74 when the neutral point position signal Cg is inputted, and inputs the reset signal to the reset terminal.
The steering angle calculation means 79 searches the steering angle map 80 and calculates the steering angle. The steering angle map 80 has a configuration in which the count value of the up / down counter 74 is associated with the steering angle. The steering angle signal is output to the steering angle signal receiving means 37 (see FIG. 1) of the first control device 6 through the output circuit 81.

  A steering angle signal transmitted from the steering angle signal output circuit 28 of the first control device 6 is input to the angle difference signal calculation means 82 via the steering angle signal reception means 85. The output of the angle difference signal calculation means 82 is connected to the steering angle determination means 83. The steering angle determination means 83 searches the target steering angle map 86 and calculates the target steering angle. The target steering angle map 86 is set so that the output increases when the angle difference with respect to the actual steering angle is large. The target steering angle signal is converted into a drive signal by the drive signal generation means 87 and output to the drive circuit 65.

  The second control device 7 is provided with a starting state signal receiving means 88. The starting state signal receiving means 88 passes the starting state signal transmitted from the starting state signal output circuit 49 of the first control device 6 to the prohibition signal generating circuit 89. The prohibition signal generation circuit 89 receives the start state signal and outputs a prohibition signal to the drive signal generation means 87.

Next, the operation of this embodiment will be described.
When the driver rotates the steering wheel 2, two pulse train signals (rotation detection signals Aw, Bw) are output to the first control device 6 according to the rotation angle from the first encoder 13. The up / down determination circuit 21 determines the rotation direction of the steering wheel 2 from the order in which the signal levels of the pulse train signals of the rotation detection signal Aw and the rotation detection signal Bw change. In the direction indicated by the arrow AA1 in FIG. 3, the rotation detection signal Bw becomes high level after the rotation detection signal Aw becomes high level. In this case, for example, it is assumed that the steering wheel 2 is steered rightward, and the up / down counter 24 is instructed to count up. Conversely, in the direction indicated by the arrow AA2 in FIG. 3, the rotation detection signal Aw becomes high level after the rotation detection signal Bw becomes high level. In this case, it is assumed that the steering wheel 2 is steered leftward, and the up / down counter 24 is instructed to count down.

The edge detection circuit 22 </ b> A detects the rising edge and the falling edge of the rotation detection signal Aw pulse, and outputs them to the OR circuit 25. Similarly, the edge detection circuit 22B detects the rising edge and the falling edge of the rotation detection signal Bw pulse, and outputs them to the OR circuit 25. The OR circuit 25 calculates the logical sum of the signals from both edge detection circuits 22A and 22B, and creates a signal that causes a pulse to rise when one of the edge detection circuits 22A and 22B detects an edge. As a result, the resolution of the pulse signal output from the first encoder 13 is quadrupled.
The up / down counter 24 counts pulse signals output from the OR circuit 25 with reference to a neutral point position corresponding to straight traveling. When the up / down determination circuit 21 instructs to count up, the input pulse is added to the count value of the number of pulses up to the previous time. When the up / down determination circuit 21 instructs to count down, the input pulse is subtracted from the count value of the number of pulses up to the previous time.

  The steering angle calculation means 26 detects the steering angle map 27 with the first count signal output as the count value of the up / down counter 24, and acquires the actual steering angle corresponding to the first count signal. The actual steering angle signal (steering angle signal) is transmitted from the steering angle signal output circuit 28 to the second control device 7.

In the second control device 7, the steering angle signal is received by the steering angle signal receiving means 85. The angle difference signal calculation means 82 calculates a steering angle corresponding to the actual steering angle (hereinafter referred to as a target steering angle). Further, the difference between the current steering angle of the tire 4 calculated by the steering angle calculation means 79 (hereinafter referred to as the actual steering angle) and the target steering angle is calculated and output as an angle difference signal.
The steering angle determination means 83 searches the target steering angle map 86 with the angle difference signal to determine the steering angle command value. This command value corresponds to a steering angle such that the angle difference is zero. The drive signal generation means 87 creates a drive signal corresponding to the command value and outputs it to the drive circuit 65, rotates the steering motor 61, and moves the steering rod 62. As a result, the angle of the tire 4 connected by the tie rod 63 or the like changes.

When the steering motor 61 rotates, two types of rotation detection signals Ag and Bg are output from the third encoder 66. The second control device 7 determines the rotation direction from the change in the signal level of each pulse train signal of each rotation detection signal Ag, Bg by the up / down determination circuit 71. The determination algorithm is the same as that of the up / down determination circuit 21 of the first control device 6. Further, the edge detection circuits 72A and 72B and the OR circuit 75 generate a pulse signal having a resolution four times that of the rotation detection signals Ag and Bg.
The up / down counter 74 counts up or down the pulse signal output from the OR circuit 75 in accordance with a command from the up / down determination circuit 71. The steering angle calculation means 79 searches the steering angle map 80 using the second count signal output as the count value of the up / down counter 74 to obtain the actual steering angle. The actual steering angle signal (steering angle signal) is input to the angle difference signal calculating means 82 and the steering angle determining means 83 and used for controlling the steering motor 61. Further, it is sent from the output circuit 81 to the first control device 6.

  In the first control device 6, the steering angle signal is received by the steering angle signal receiving unit 37, and the steering angle corresponding to the actual steering angle (hereinafter referred to as the target steering angle) is calculated by the angle difference signal calculating unit 29. To do. Further, an actual steering angle (hereinafter referred to as an actual steering angle) calculated by the steering angle calculation means 26 is acquired as a steering angle signal, and an angle difference between the target steering angle and the actual steering angle is calculated. The steering reaction force calculation means 30 searches the steering reaction force map 38 based on the angle difference signal obtained at this time, and the steering reaction force is determined. The first drive signal generating means 39 generates a drive signal for the drive motor 12 according to the steering reaction force, and energizes the drive motor 12 from the drive circuit 16 via the drive signal switching means 40. A force is generated by the rotation of the drive motor 12 on the steering shaft 3 that is a rotating shaft connected to the drive motor 12. This force acts as a load for the driver who operates the steering wheel 2. As a result, the steering angle of the steering wheel 2 and the actual steering angle of the tire 4 quickly coincide with each other. In addition, information such as road surface conditions is transmitted to the driver, improving operability.

Here, the operation at the start of the vehicle control device 1 will be described.
When the ignition switch 43 is OFF, the first control device 6 and the second control device 7 do not operate. Therefore, when the steering wheel 2 is rotated or the direction of the tire 4 is changed by an external force or the like, The actual steering angle may not match the actual steering angle. In this state, when the ignition switch 43 is turned on, a voltage is applied from the power supply 44 to the constant voltage generation circuit 45. When the voltage of the constant voltage generation circuit 45 exceeds the threshold value registered in the memory 47, the voltage comparison unit 46 outputs a start state signal from the start state signal generation unit 41. The starting state signal is output for a time determined by the timer 41A. The time interval at this time is a time sufficient to make the actual steering angle substantially coincide with the actual steering angle, and is a time that does not hinder driving. When the start state signal is output, it is transmitted from the start state signal output circuit 49 to the second control device 7, and the timer 48 starts counting.

  The start state signal is input to the drive signal switching means 40, and the drive signal output from the first drive signal generating means 39 is invalidated based on the actual steering angle. The start state signal is further input to the second drive signal generation means 42, and the drive signal created by the second drive signal generation means 42 is input to the drive circuit 16 through the drive signal switching means 40 to drive the drive motor 12. Drive. The drive amount and drive direction of the drive motor 12 are determined from the angle difference acquired from the angle difference signal calculation means 29 by the angle difference signal comparison means 31.

  As a result of the drive motor 12 being driven, the steering shaft 3 is rotated and the steering wheel 2 is rotated so as to coincide with the steering angle of the tire 4. Since the steering angle of the steering wheel 2 is input from the first encoder 13 to the first control device 6, if this data is monitored by the angle difference signal comparison means 31, the movement of the steering wheel 2 can be confirmed. The angle difference signal comparison means 31 is driven by the drive signal generation means 42 when the actual steering angle substantially coincides with the actual steering angle, that is, when the value of the angle difference signal is equal to or smaller than the set angle stored in the memory 50. Stop signal generation. Further, the count of the timer 48 is stopped. The angle at this time may be zero or a constant value. The constant value is a value that does not greatly change the traveling direction with respect to the angle of the steering wheel 2 when the vehicle starts traveling, and an optimal value can be set in advance depending on the vehicle type.

On the other hand, in the second control device 7, the starting state signal is input from the starting state signal receiving means 88 to the prohibition signal generating circuit 89. The prohibition signal generation circuit 89 generates a prohibition signal and stops the generation of the drive signal in the drive signal generation means 87 while the start state signal is input. For this reason, the tire 4 is not steered and only the steering wheel 2 is driven to reduce the angular difference.
Then, when the time determined by the timer 41A elapses, the generation of the start state signal ends. Thereafter, in the first control device 6, the drive signal switching means 40 adopts the drive signal of the first drive signal generating means 39. In the second control device 7, the generation of the prohibition signal is stopped, and the steering motor 61 can steer the tire 4. Driving is started in a state where the angles of the steering wheel 2 and the tire 4 are substantially coincident, and the tire 4 is steered in accordance with the steering of the driver.

  If the count value of the timer 48 reaches a predetermined value before the actual steering angle substantially coincides with the actual steering angle, the alarm signal generating means 51 turns on the lamp 52. The driver turns on the ignition switch 43 again, or manually rotates the steering wheel 2.

In this embodiment, when the ignition switch 43 is turned on, the steering wheel 2 is rotated in accordance with the steering angle of the tire 4, so that the tire 4 and the steering wheel are steered with the ignition switch 43 turned off. Even when the angles of the wheels 2 are not coincident, the operation can be started in a state where the angles of the two are substantially coincident. For this reason, the progress of the vehicle can be further stabilized at the start of driving.
Since the angle difference is reduced by driving the steering wheel 2 at the time of starting, less force is required compared with the case where the tire 4 is steered. Since the steering of the tire 4 is prohibited while the steering wheel 2 side is driven, the angle difference can be reduced in a short time.

Note that the present invention can be widely applied without being limited to the above-described embodiment.
For example, you may comprise the 1st, 2nd control apparatuses 6 and 7 from one control apparatus.

It is a block diagram which shows the structure by the side of the steering wheel of the control apparatus for vehicles which concerns on embodiment of this invention. It is a block diagram which shows the structure by the side of the steering gear of the control apparatus for vehicles. It is a figure explaining the signal input into an up / down counter.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Control apparatus for vehicles 2 Steering wheel 3 Steering shaft 4 Tire (steering wheel)
5 Steering gear 6 First control device 12 Drive motor 24 Up / down counter (first counter, first position detecting means)
26 steering angle calculation means 29 angle difference signal calculation means 30 steering reaction force calculation means 31 angle difference signal comparison means 39 first drive signal generation means 40 drive signal switching means 41 start state signal generation means 42 second drive signal generation means 43 ignition switch 44 power supply 48 timer 51 alarm signal generating means 52 lamp 61 steering motor 66 third encoder 74 up / down counter (second counter, second position detecting means)
89 Prohibition signal generation circuit

Claims (4)

A steering shaft rotatably supported on the vehicle body;
A steering wheel attached to the steering shaft and rotating together with the steering shaft;
A first counter that detects rotation of the steering shaft and that receives the pulse train signal from an encoder that generates a pulse train signal as the steering shaft rotates, counts the pulse train signal, and generates a first count signal. First position detecting means comprising:
Steering angle calculation means for converting the first count signal output from the first counter of the first position detection means into a signal indicating the amount of rotation of the steering wheel, and outputting as a steering angle signal;
A drive motor capable of rotating the steering wheel;
A steering wheel supported to be steerable by a vehicle body;
A driving means having an electric motor and changing a steering angle of the steering wheel with respect to a vehicle body;
A change in the steering angle of the steering wheel is detected, a detection signal supplied from an encoder that generates a detection signal in accordance with a change in the steering angle of the steering wheel is counted, and a second count signal is output. Second position detecting means having a second counter;
The steering which converts the 2nd count signal supplied from the 2nd counter of the 2nd position detection means into the signal which shows the change amount of the steering angle of the steering wheel, and outputs it as a steering angle signal An angle calculation means;
A steering angle signal is supplied from the steering angle calculation means, and a steering angle signal is supplied from the steering angle calculation means. The steering angle signal is compared with the steering angle signal, and an angle difference that is the difference between the two is calculated. An angle difference signal calculating means for generating a signal;
First drive signal generation means for supplying an angle difference signal from the angle difference signal calculation means and creating a drive signal of the drive motor based on the angle difference signal;
Starting state signal generating means for generating a starting state signal only for a predetermined time when the power is turned on;
And a second drive signal generating means for generating a drive signal of the drive motor so that an angle difference between the steering angle and the steering angle is reduced when a start state signal is generated. Control device.   The vehicle control device according to claim 1, further comprising a prohibition signal generation circuit that stops the steering of the steering wheel when a start state signal is generated.   A timer that starts counting when a start state signal is generated, and an alarm signal is generated if the count value of the timer reaches a predetermined value before the angle difference between the steering angle and the steering angle falls below a predetermined value. The vehicle control device according to claim 1, further comprising an alarm signal generation unit.   The drive signal generated by the second drive signal generation means is supplied to the drive motor only while the start state signal is generated. Otherwise, the drive signal generated by the first drive signal generation means And a drive signal switching means for switching the steering reaction force calculated according to the difference between the actual steering angle and the steering angle to act on the steering wheel. The vehicle control device according to any one of claims 1 to 3.

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