JPH07104140B2 - Center position determination method for rotating body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention is suitable for determining the center position of a rotating body that is used to determine the rotational center position of a rotating body that rotates in conjunction with steering of a vehicle. It is about.

[Conventional technology]

Conventionally, in vehicles such as automobiles, a plurality of slits are provided at equal angular intervals in a rotating disk that rotates in association with steering of a steering wheel, and two photo interrupters are arranged adjacent to each other at a position where the slits pass, It performs various controls linked to the steering of the steering wheel.

That is, in association with steering of the steering wheel, the first and second
In the photo interrupter, a pulsed electric signal having the same waveform and a phase difference of approximately 90 ° is generated, and the electric signal is counted to detect the rotation direction and the rotation position of the handle.

[Problems to be Solved by the Invention]

However, according to such a conventional rotational position detector, in the case where the counter causes a miscount due to electric noise or the like, there is no means for correcting the error, and therefore the system is accumulated due to the error accumulation. There was a problem that malfunction occurred.

Also, in order to reduce power consumption, if the power supply to the rotary position detector is cut off after the ignition switch is turned off, the rotation position change of the steering wheel until the next ignition switch is turned on causes an error. ,
It was something that was accumulated.

[Means for Solving the Problems]

The present invention has been made to solve such a problem, and a predetermined rotation angle position of a rotating body that rotates in a clockwise direction and a counterclockwise direction in conjunction with steering of a vehicle steering wheel is set as an origin position. Of the origin position that is located for each rotation,
After the origin position is detected, the origin position that continues to stay within a predetermined rotation angle range centered on the origin position while the vehicle travels for a predetermined distance is determined as the rotation center position of the rotating body.

[Action]

Therefore, according to the present invention, among the origin positions located every other rotation of the rotating body, while the vehicle travels a predetermined distance after the origin position is detected, the vehicle continues to stay within a predetermined rotation angle range around the origin position. The origin position can be determined as the rotation center position of the rotating body.

〔Example〕

Hereinafter, the method for determining the center position of the rotating body according to the present invention will be described in detail. FIG. 1 is a block diagram showing an embodiment of the center position determining method. In the figure, 5 is an UP / DOWN switching circuit that receives a pulse-shaped electric signal sent from a rotational position detection sensor (Fig. 2) and sends processing signals (up signal and down signal) according to steering of the steering wheel, 6 Reference numerals 7 and 7 denote first and second UP / DOWN counters to which the processing signal sent by the UP / DOWN switching circuit 5 is input, and 8 an output terminal (not shown) at a position corresponding to the count value counted by the counter 6. ) Is selected and its level is set to "L" or "H", and 9 is a lamp drive circuit that changes the irradiation direction of the headlight (not shown) according to the output state of the decoder 8.

The rotational position detection sensor shown in FIG. 2 is composed of a rotating disc 1 that rotates in association with steering of a vehicle steering wheel, and photo interrupters 2 to 4 having a light emitting element and a light receiving element. Photo interrupters 2 and 3 are
It is arranged adjacent to the passage position of the slits 1a of the same shape opened at equal angular intervals on the outer peripheral surface of the rotary disc 1.
The photointerrupters 2 and 3 are adapted to generate a pulse-shaped electric signal having the same waveform and a phase difference of approximately 90 ° by passing through the slit 1a as the rotary disc 1 rotates. The electrical signal is input to the UP / DOWN switching circuit 5. Also, the rotating disk 1
A slit 1b for detecting the origin position is independently provided at a predetermined rotation angle position on the outer peripheral surface of the slit.
The passage of 1b is detected by the photo interrupter 4. That is, the slit 1b is the photo interrupter 4
Is set as the origin position of the rotary disc 1, and this origin position is set in correspondence with the steering position of the steering wheel (hereinafter, this steering position is referred to as the steering wheel center) during straight traveling. That is, in the handle center, the rotary disc 1 is located at the origin position as shown in the figure (hereinafter, this position is referred to as the rotary center of the rotary disc), and the handle centered on the handle center The origin position of the rotary disc 1 is detected to be deviated by 360 ° for each rotation in the clockwise direction and the counterclockwise direction. Generally, a steering wheel of an automobile can rotate less than two rotations in a clockwise direction (hereinafter, rightward direction) and a counterclockwise direction (hereinafter, leftward direction) about a steering wheel center. The photo interrupter 4 detects the total of three origin positions including the rotation center, and at the time of detecting the origin position, one of the input ends of the AND gate 10 in FIG. A signal is input.

On the other hand, the UP / DOWN switching circuit 5 processes the inputted pulse-shaped electric signal and sends out the number of up signals and down signals corresponding to the right steering amount and the left steering amount of the steering wheel, The UP / DOWN counters 6 and 7 are adapted to count up or count down the count value by the number of input up signals or down signals. That is, the count value in the UP / DOWN counter 6 is set to zero with reference to the time when the rotary disc 1 is at the rotation center, and the count value is sequentially increased by steering the steering wheel to the right, and the count value is incremented by steering to the left. The values are decreasing sequentially. Then, the count value sent by the UP / DOWN counter 6 is input to the decoder 8, and the operation of the lamp drive circuit 9 based on the output state of the decoder 8 controls the irradiation direction of the headlight in conjunction with steering of the steering wheel. It is supposed to be done. Also,
It goes without saying that the UP / DOWN counter 7 is also configured to sequentially increase the count value by steering the steering wheel to the right and sequentially decrease the count value by steering the steering wheel to the left. When the "H" level is reached, the count value of the counter 7 is reset and returns to zero.

On the other hand, the Q-bar output of the RS flip-flop circuit 11 is input to the other input terminal of the AND gate 10, and the output of the AND gate 10 is set to the S input of the flip-flop circuit 11. Is entered as. Then, the Q output of the flip-flop circuit 11 is inputted to one end of the AND gate 12,
A pulse signal (distance signal) corresponding to the traveling distance is input to the other end of the AND gate 12. The distance signal passing through the AND gate 12 is input to the frequency divider 13, and the frequency divider 13 overflows and UP / DOWN every time this distance signal is input as a travel distance of 200 m or more.
A load signal is sent to the counter 6.
Then, when the load signal is input, the UP / DOWN counter 6 takes in the count value of the UP / DOWN counter 7 at that time and rewrites the count value. That is, the count value of the UP / DOWN counter 7 is transferred to the UP / DOWN counter 6, and the count value of the counter 6 is rewritten to the transferred count value.

On the other hand, the count value of the UP / DOWN counter 7 is adapted to be compared by the comparator 15, and the comparator 15 has a range of ± 180 with respect to the rotation center of the rotating disk 1.
The count value ± x corresponding to the rotation angle position of ° is set as the comparison reference count value. That is, the comparator 15 sends a reset signal to the frequency divider 13 when the count value input via the UP / DOWN counter is not within the range of ± x counts. The reset signal sent from the comparator 15 and the load signal sent from the frequency divider 13 are branched and input to the OR gate 16, and the output of the OR gate 16 is given to the R terminal of the prep-flop circuit 11. It has become a thing.

Next, the operation of the apparatus thus configured will be described. That is, it is assumed that the vehicle is traveling straight ahead and the rotating disc 1 that rotates in association with steering of the steering wheel is at the rotation center position as shown in FIG. At this time, UP / DOWN
The count value of the counter 6 should actually be zero, but it is a count value deviated from zero due to the above-mentioned electric noise or the handle rotation after the ignition switch is turned off. There are cases. When such a deviated count value is input to the decoder 8, there occurs a problem that the irradiation direction variable operation of the headlight controlled by the decoder 8 deviates corresponding to the count value. However, in the present embodiment, since the correction operation as described below is performed promptly, it becomes possible to control the irradiation direction of the headlight in conjunction with steering of the steering wheel without any trouble.

That is, it is no exaggeration to say that most of the roads of automobiles are straight roads, and the vehicle will not travel a long distance with the steering wheel rotated once. That is, even if the origin position detection signal is generated at the one-turn steering position of the steering wheel, its generation period is short, and the steering wheel returns to the vicinity of the steering wheel center after traveling a short distance. In a study based on the inventor's actual vehicle, the vehicle sometimes travels on the U-turn road with one rotation, but the traveling distance before returning the steering wheel to the vicinity of the steering wheel center is less than 200 m. In other words, after the origin position detection signal is generated at the 1-turn steering position, the rotation angle must be 18
Steering is performed at 0 ° or more. Therefore, after the origin position detection signal is generated, 18
If the steering wheel is not steered by 0 ° or more, the origin position at that time may be determined as the rotation center position.

Now, it is assumed that the flip-flop circuit 11 and the frequency divider 13 are in the initial set state, and the origin position detection signal is generated at the rotation center position of the rotating disk 1, that is, the straight steering position. At this time, the origin position detection signal of "H" level is input to the AND gate 10. At the other end of the AND gate 10, the Q bar output of the flip-flop circuit 11, that is, "H"
Since the level signal has already been input, the origin position detection signal input to one end of the signal passes through the AND gate 10,
The UP / DOWN counter 7 is reset and the flip-flop circuit 11 is set. This allows UP / DOW
The count value of the N counter 7 becomes zero, and the flip-flop circuit 11 sets the levels of its Q output and Q bar output to "H" and "L". Flip-flop circuit 11
The gate of the AND gate 10 is closed by inverting the Q bar output of the AND gate to the “L” level, but the gate of the AND gate 12 is opened by the Q output thereof being turned to the “H” level. Therefore, the distance signal passes through the AND gate 13 and starts to be input to the frequency divider 13. At this time, since the count value of the counter 7 has already become zero due to the origin position detection signal input via the AND gate 10, the comparator 15 does not send the reset signal and the frequency divider 13 is input. The frequency division operation of the distance signal is continuously performed. This frequency dividing operation is continuously performed not only when the count value of the counter 7 is zero but also within the range of ± x counts. That is, if the steering is within ± 180 ° around the steering wheel center, the comparator 15 does not send the reset signal, and the frequency dividing operation of the frequency divider 13 is continuously performed. When the vehicle travels 200 m in such a state, the frequency divider 13 overflows the input distance signal, and the load signal is sent to the UP / DOWN counter 6. Upon receiving the load signal, the UP / DOWN counter 6 takes in the current count value of the UP / DOWN counter 7 and rewrites the count value. That is,
If the rotary disc 1 is at the rotation center position at this point, the count value in the UP / DOWN counter 7 is zero, and this count value is transferred to the UP / DOWN counter 6
The count value of becomes zero. At this time, the rotating disc 1
If is not in the rotation center position and is rotating (within ± 180 °), the UP / DOWN counter 7 is performing accurate counting with the rotation center position as the zero reference, and this count value is displayed in the counter 6. Will be transferred. That is, even if the UP / DOWN counter 6 makes a miscount, the UP / DOWN counter 6 takes in an accurate count value based on the rotation center position, and corrects it appropriately. The load signal sent from the frequency divider 13 is input to the R terminal of the flip-flop circuit 11 via the OR gate 16, and the flip-flop circuit 11 is reset to prepare for the next origin position detection signal.

By the way, in the above operation, the operation after the origin position detection signal is generated at the straight-ahead steering position has been described, but the origin position detection signal is generated even at the one-turn steering position while the vehicle is traveling. Now, it is assumed that the flip-flop circuit 11 and the frequency divider 13 are in the initial set state and the origin position detection signal is generated at the one-turn steering position. At this time, the origin position detection signal of "H" level is input to the AND gate 10 in the same manner as described above, and UP / DOWN
As the count value of the counter 7 becomes zero, the distance signal starts to be input to the frequency divider 13. At this time, since the count value of the UP / DOWN counter 7 is zero, the comparison reference count value is within the range of ± x, so the comparator 15 does not send the reset signal to the frequency divider 13 and the frequency divider 13
The frequency division operation in is continued. However, as described above, the travel distance from returning the steering wheel from the one-turn steering position to near the steering wheel center is less than 200 m. Therefore, the count value of UP / DOWN counter 7 is 200m.
Until the vehicle runs, the steering wheel rotation angle is counted over 180 °, and it is outside the range of comparison reference count value ± x. At this point, the comparator 15 sends out an "H" level signal and resets the frequency divider 13. Where the divider
The timing of the reset signal input to 13 is
This is the period from when the distance signal is input to the vehicle until the vehicle travels 200m. Therefore, the frequency divider 13 is reset without waiting for the overflow of the distance signal, and the UP / DOWN counter 6
No load signal is sent to. That is, the count value of the counter 7 at this time is a count value when the one rotation position in the right or left direction of the rotary disc 1 is determined as the temporary rotation center position, and the UP / DOWN counter is used by using this count value. The count value in 6 is not corrected. The reset signal sent from the comparator 15 is also input to the R terminal of the flip-flop circuit 11 via the OR gate 16, and the flip-flop circuit 11 is reset to prepare for the next origin position detection signal.

As described above, according to the device of this embodiment, the UP / D
The OWN counter 7 counts each origin position as a provisional rotation center position, but the count value transferred to the UP / DOWN counter 6 is the count value corresponding to the true rotation center position. Accurate and appropriate correction using the value is performed, and the irradiation direction of the headlight can be controlled without any trouble in conjunction with steering of the steering wheel. In addition, once the origin position detection signal is generated at the rotation center position, the UP / DOWN counter 6 is properly corrected even if the steering wheel is being steered thereafter (within ± 180 °), and the curve is traveling. Even if there is, the correction of the irradiation direction variable operation of the headlight is surely performed.

In this embodiment, the comparison reference count value ± x in the comparator 15 is set to ± 180 as the rotation angle of the handle.
Although it is set to a value corresponding to °, it may not necessarily correspond to ± 180 °, and the dividing ratio of the frequency divider 13 is set to 200 m as the traveling distance, but it is not limited to 200 m.

Further, in the present embodiment, the correction operation of the counter in the so-called cornering lamp system in which the irradiation direction of the headlight is changed by interlocking with the steering of the steering wheel has been described. The counter in the system may be corrected.
Further, the correction is not limited to such a counter,
Various controls can be performed based on the determined rotation center,
Its utility value is extremely high.

〔The invention's effect〕

As described above, according to the method for determining the center position of a rotating body according to the present invention, among the origin positions located every other rotation of the rotating body, the origin position is the center while the vehicle travels a predetermined distance after the origin position is detected. The origin position that continues to stay within the specified rotation angle range is determined as the rotation center position of this rotating body, and it becomes possible to accurately determine the straight steering position of the vehicle. It becomes possible to correct the miscount of the counter in the position detector.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a method for determining a center position of a rotating body according to the present invention, and FIG. 2 is a schematic diagram showing a rotational position detection sensor used in this center position determining method. 1 ... Rotating disk, 1b ... Origin position detection slit, 2
4 …… Photo interrupter, 6,7 …… UP / DOWN counter,
11 …… RS flip-flop circuit, 13 …… divider, 15 ……
comparator.

Claims (1)

[Claims] 1. A rotating body that rotates in a clockwise direction and a counterclockwise direction in conjunction with steering of a steering wheel of a vehicle, and an origin position where a predetermined rotation angle position of this rotating body is an origin position and the rotating body is positioned for each rotation. An origin position detecting means for detecting the position of the rotor, and the position of the rotor is determined for each rotation of the rotating body within a predetermined rotation angle range around the origin position while the vehicle travels a predetermined distance after the origin position is detected. A method for determining a center position of a rotating body, characterized in that an origin position that continues to be stopped is determined as a rotation center position of the rotating body in a clockwise direction and a counterclockwise direction.