JPH05100745A - Position controller - Google Patents

Abstract

PURPOSE:To provide an inexpansive position controller having an excellent reproducibility even if forward rotation and backward rotation are repeated. CONSTITUTION:This position controller is constituted of a DC drive motor 101, a means 102 to generate a pulse synchronously with the rotation of the motor 101, the means 103 to set a target count value, the means 104 to integrate the pulse outputted from the number of revolution detecting means 102 until it coincides with the target count value, and simultaneously, output an on- forward integration signal or an on-backward integration signal, the means 105 to rotate the DC drive motor 101 forward or backward in accordance with the on-forward integration signal or the on-backward integration signal, and an edge detecting means 106 which is installed between the number of revolution detecting means 102 and the means 104, and during the forward rotation, detects the edge of one side of the pulse and outputs a count increment command, and during the backward rotation, detects the edge of the other side and outputs a count decrement command.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position control device using a direct current motor as a drive source, and more particularly to a position control device in which the displacement of the direct current motor is small even after the direct rotation or the reverse rotation.

[0002]

2. Description of the Related Art In recent years, many automobile interiors have been electrified, and one of them is posture control of a driver's seat. FIG. 8 is a perspective view of a driver's seat in which a DC motor that is an actuator is incorporated, and four motors of a reclining adjustment motor 801, a slide adjustment motor 802, a front vertical adjustment motor 803, and a rear vertical adjustment motor 804 are provided. It has been incorporated.

FIG. 9 is a functional diagram of a control circuit conventionally used for one of the four motors, for example, a reclining adjustment motor 801.
2, a target value setting unit 203, a counter unit 204, and a rotation direction switching unit 205. Rotation speed detection unit 202
Is composed of a disk 2021 and a detector 2022 directly attached to the drive shaft of the motor 801, for example.

Two magnets 2021a and 2021b are attached to the disk 2021 so as to face each other by 180 degrees.
A Hall element detector is used as the detector 2022. As a result, from the detector 2022,
Two pulses are output for each rotation. This pulse is processed by the pulse edge detection unit 210 and then incremented or decremented according to the rotation direction of the motor that is input to the counter unit 204 and output from the comparison unit 206.
Then, the comparison unit 206 compares the target value set by the target value setting unit 203 with the value of the counter unit 204, and causes the motor 801 to rotate normally or reversely through the rotation direction switching unit 205 until they match.

The rotational force of the motor 401 is reduced by the gear 210, the torque is amplified, and the angle of the backrest of the driver's seat is changed. FIG. 10 is a timing diagram showing the output pulse of the detector and the pulse input to the counter.
(A) shows the output pulse of the detector 2022, (B) shows the pulse count timing during forward rotation, and (C) and (D) show the pulse count timing during reverse rotation.

As the pulse counting method in the counter section 204, one of the following two methods is used. 1) Count the rising or falling edges of the output pulse of the detector 2022. 2) Count both rising and falling edges of the detector 2022 output pulse.

[0007]

However, each of the cases has the following problems. That is, in the case of the method of 1), for example, when counting the rising edges, when the pulse is normally rotated from the position of a in FIG. 10A by 3 pulses, it stops at the position of b or c due to inertia. Next 3
When the pulse reverse rotation starts from b,
Although it returns to a as shown in (C), when the reverse rotation is started from c, it stops at d as shown in FIG.

When the backrest is used for adjusting the angle of the backrest, the backrest is raised against the weight of the driver, and when the backrest is tilted, the leaning angle is promoted by the weight of the driver. Therefore, an overshoot is accumulated at every adjustment, and it becomes impossible to ignore the deviation from the set value.

To solve this problem, the method 2) is usually applied. In this method, the pulse edge detector 21 is used.
0 and the number of pulses read by the counter unit 204 are doubled, and high-speed processing is required. In particular, when the motor 801 is miniaturized, the motor 80 is kept in order to maintain the driving torque.
It is necessary to rotate 1 at a high speed, and the increase in the number of pulses to be counted inevitably requires the use of hardware having a high processing speed, resulting in an increase in cost.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a position control device which has a good reproducibility even when the forward rotation and the reverse rotation are repeated and which is inexpensive.

[0011]

FIG. 1 is a basic configuration diagram of a position control device according to a first invention, in which a direct-current drive motor 1 is used.
01, a rotation speed detection means 102 for generating a pulse in synchronization with the rotation of the DC drive motor 101, a target count value setting means 103 for setting a target count value, and a target count set by the target count value setting means 103. Counting means 104 that counts the pulses output from the rotation speed detecting means 102 and outputs a forward-direction integrating or reverse-direction integrating signal until they match the value, and the counting means 10.
A forward rotation between the motor control means 105 for rotating the direct-current drive motor 101 in the forward direction or the reverse direction in accordance with the forward integration or reverse integration signal output from the rotation speed detection means 102 and the counting means 104. During rotation, one edge of the pulse output from the rotation speed detection means 102 is detected and an increment command is given to the counting means 104. During reverse rotation, the other edge of the pulse output from the rotation speed detection means 102 is detected. The edge detection unit 106 outputs a decrement command to the counting unit 104.

In the second invention, the edge detecting means 10
Reference numeral 6 is a change determination means for determining whether or not there is a change in the signal of the rotation speed detection means 102, and rotation speed detection is performed during reverse rotation with reference to one edge of the rotation speed detection means 102 during forward rotation. Frequency dividing means for dividing the output of the rotation speed detecting means 102 by ½ based on the other edge of the means 102,
Composed of.

[0013]

The pulse edge for counting by the counter is switched to one edge during the forward rotation and to the other edge during the backward rotation, so that the position can be controlled with good reproducibility even when the forward rotation or the reverse rotation is repeated. it can.

[0014]

FIG. 2 is a hardware configuration diagram of an embodiment of a position control device according to the present invention. For example, a rotation speed detection mechanism 202 including a disc 2021 and a detector 2022 is attached to the rotation shaft of the DC drive motor 201 for adjusting the reclining angle.

Two magnets 2021a and 2021b are attached to the disk 2021 as markers facing each other by 180 degrees. A Hall element is used as the detector 2022, and a pulse signal is output each time a magnet is detected. The driving force of the DC drive motor 201 is decelerated and torque-amplified by the gear mechanism 210 attached to the shaft, and is used to change the angle of the backrest of the driver's seat.

The pulse detected by the detector 2022 is guided to the controller 220. The control unit 220 is constructed as, for example, a microcomputer system, and is composed of a CPU 2202, a memory 2203, a pulse input interface 2204, a switch interface 2205, and an output interface 2206 centering on a bus 2201.

The output of the detector 2022 is captured by the controller 220 via the pulse input interface 2204. The following three switches are connected to the switch interface 2205. 2205a ... A switch for instructing the rotation direction during manual operation, and for example, the angle of the backrest continuously changes while the switch is on.

2205b ... A memory switch for storing the current position, which has, for example, two storage memories and can store different positions. 2205c ... A switch for selecting a reproduction mode, which can be set to one position of the storage memory selected by the storage switch. Further, the output interface 2206 is connected to the rotation direction switching unit 205.

The rotation direction switching unit 205 switches the rotation direction of the motor 201 by switching the direction of the current flowing from the battery 230 to the motor 201. FIG. 3 shows the control unit 2.
It is a flowchart of the main routine performed by 20, and is performed as an interrupt process at every predetermined time. In step 301, a count command DC processed by a pulse edge processing routine described later is read.

In step 302, it is judged whether or not the value of the count command DC has changed, and when it has changed, the value (1, 0,
-1) is counted, and it is determined in step 303 whether or not the manual mode switch 2205a is operated so as to perform a normal rotation or a reverse rotation operation. If an affirmative decision is made in step 303, a flag (F1, F indicating the direction of rotation)
2) is set and while the manual mode switch 2205a is in the ON state, the motor 201 is continuously rotated in the normal direction or the reverse direction in the rotation direction to change the angle of the backrest. When the desired angle is reached, the manual mode switch 2205a is set to the neutral position and turned off.

Note that it is common to incorporate an interlock logic so that the forward rotation and reverse rotation commands are not output at the same time due to an erroneous operation of the manual mode switch 2205a. When a negative determination is made in step 303, it is determined in step 305 whether or not the memory switch 2205b is in a memory mode in which the memory switch 2205b is operated.

When the affirmative determination is made in step 305, the process proceeds to step 306, and the current pulse edge count value is stored in the memory designated by the storage switch 2205b. That is, the desired position can be stored by operating the memory switch 2205b after changing to the desired position with the manual mode switch 2205a. Meanwhile, step 3
When a negative determination is made in 05, it is determined in step 308 whether or not the reproduction switch 2205c is operated.

When the affirmative judgment is made in step 308, the reproducing operation is executed in step 307, and when the negative judgment is made, that is, in any mode, the processing is ended. FIG. 4 is a flowchart of a pulse edge routine for processing a pulse edge, which is executed as interrupt processing at the same time intervals as the main routine. In step 401, the sensor output is read, and in step 402, based on the rotation direction flags F1 and F2 set in step 304 of the main routine described above or step 507 or 508 of the reproduction operation routine described later, whether the rotation direction is normal rotation or not. Is determined.

When it is determined in step 402 that the rotation is normal, the process proceeds to step 403, and it is determined whether or not the rising edge of the pulse is detected. If a rising edge is detected, the count command DC is set to "1" in step 404.
After setting to, go to step 408. On the contrary, if a negative determination is made in step 403, the count command DC is reset to "0" in step 405, and then the process proceeds to step 408.

If a negative decision is made in step 402 that it is not forward rotation, then the operation proceeds to step 409, in which it is decided whether or not the rotation direction is the reverse rotation direction. When it is determined that the reverse rotation is performed, the process proceeds to step 406, and it is determined whether or not the trailing edge of the pulse is detected. If an affirmative decision is made in step 406, the operation proceeds to step 407, in which the count command DC
Is set to "-1", the process proceeds to step 408.

When the determinations at steps 403, 406 and 409 are negative, the process proceeds to step 405 in any case. In step 408, the count command DC is written in a predetermined address of the memory 2203. FIG. 5 is a flowchart of the reproduction operation routine for the reproduction operation executed in step 307 of the main routine.

In step 501, the target value T stored in a predetermined address of the memory is read. Step 502
At 503, the target value T and the current count value C are compared. If the difference between the target value T and the current count value C is larger than a predetermined error ε, the routine proceeds to step 507, where the flag F1 indicating normal rotation is set to "1", and at step 505, via the output interface 2206. And outputs a forward rotation command to the rotation direction switching unit 205.

On the contrary, if the difference between the target value T and the current count value C is smaller than a predetermined error -ε, step 50
7, the flag F2 indicating reverse rotation is set to "1",
In step 505, a reverse rotation command is output to the rotation direction switching unit 205 via the output interface 2206. Note that these flags F1 and F2 are the same flags that are operated in the main routine described above.

If both of the determinations at step 502 and step 503 are negative, the process proceeds to step 506 to output a stop command to the rotation direction switching unit 205. FIG. 6 is a circuit diagram of an embodiment of the rotation direction switching unit 205, which is composed of two relays 2051 and 2052. Relay 2
Reference numeral 051 has an a contact 2051a which is closed when a forward rotation command is applied and a b contact 2051b which is closed when a forward rotation command is not applied. The a contact 2051a is at the + terminal of the battery 230, The B contact 2051b is connected to the ground.

The relay 2052 has an a-contact 2052a which is closed when a reverse rotation command is applied and a b-contact 2052b which is closed when a reverse rotation command is not applied. The a-contact 2052a is + of the battery 230. B contact 2 at the terminal
052b is connected to ground. When the forward rotation command is output via the output interface 2206, the relay 2
051 is switched to the a-contact side to form a circuit, and the motor 201 rotates in the forward direction.

When a reverse rotation command is output, a current flows in the reverse direction, and the motor 201 rotates in the reverse direction. In addition, in the pulse edge processing, in order to avoid erroneous detection due to so-called pulse chattering, it is common to provide a bounce elimination function that ignores the signal when the pulse does not maintain a constant value for 100 microseconds, for example.

According to the second aspect of the invention, by incorporating a pulse frequency dividing processing function into the bounce eliminate routine, it is possible to count the rising edge or the falling edge according to the rotating direction without modifying the main routine. FIG. 7 is a flowchart of a bounce elimination routine incorporating frequency division processing.
It is executed in place of the pulse edge processing routine shown in FIG.

This routine is interrupted at regular intervals of 1 ms, for example. First, in step 701, the sensor output is read and stored in A. In step 702, a timer that counts 100 microseconds is started. In step 703, the sensor output is read and stored in B. In step 704, it is determined whether or not 100 microseconds have elapsed, and if a negative determination is made, step 70
Return to 3.

In step 705, it is determined whether or not the read values A and B of the sensor output are equal. If a negative determination is made, it is determined that the sensor is chattering, and the processing of this routine ends. When an affirmative decision is made in step 705, the routine proceeds to step 706, and it is decided whether or not the outputs D and A at the time of execution of this routine last time are equal.

If an affirmative decision is made in step 706, it is assumed that the sensor output has not changed, and the execution of this routine ends. On the contrary, if a negative determination is made in step 706, the process proceeds to step 707 to determine whether or not the detected sensor change is a rising edge. If it is a rising edge, an affirmative decision is made in step 707 and step 7
In step 08, it is determined from the rotation direction flags F1 and F2 whether the rotation direction is positive.

If an affirmative judgment is made in step 708, the routine proceeds to step 710, and if a negative judgment is made, the routine proceeds to step 712.
If it is a falling edge, a negative determination is made in step 707 and the flow proceeds to step 709 to rotate direction flags F1 and F2.
It is determined whether or not the rotation direction is opposite from the above. If the determination is affirmative, step 710 is performed. If the determination is negative, step 71 is performed.
Go to 2.

At step 710, the value of the count command DC is inverted, that is, it is set to "0" when it is "1" and set to "1" when it is "0". Count command D in step 712
After outputting C, the value of D is replaced with the value of A to prepare for the next process. Through the above processing, step 70 is performed during normal rotation.
7, 708 and 710 invert the DC value at each rising edge. Also, when reversing, steps 707 and 7
09 and 710 invert the value of DC at each rising edge.

Therefore, the sensor output is 1 / regardless of the rotation direction.
The frequency is divided by two, and the timing at which DC changes is the same. FIG. 11 is a detailed flowchart of the pulse edge count process of step 302 of the main routine shown in FIG. 3 when the bounce eliminate routine shown in FIG. 7 is used.

In step 3021, it is determined whether or not a DC rising or falling edge has occurred. When a positive determination is made, it is determined in steps 3022 and 3024 whether the rotation is normal or reverse based on the flag F1 or F2. In the case of normal rotation, the counter value C is incremented in step 3023, and in the case of reverse rotation, the counter value C is decremented in step 3025.

It should be noted that this step 3021 to step 3
The processing up to 025 is the same as the processing used in the conventional method 2) (a method of counting both the rising and falling edges of the sensor output). Therefore, according to the present embodiment, even if the frequency of the pulse which is the sensor output becomes high, the frequency is divided into 1/2, so that hardware having a high processing speed is not required, and even when the forward / reverse rotation is repeated. Position control can be performed with good reproducibility.

Further, according to the second invention, it becomes possible to incorporate the pulse frequency dividing processing into the bounce elimination processing routine.

[0042]

According to the position control device of the present invention, by counting the rising edge in the forward rotation and the falling edge in the reverse rotation, the position is controlled with good reproducibility even when the forward rotation and the reverse rotation are repeated. It becomes possible.

[Brief description of drawings]

FIG. 1 is a basic configuration diagram of a position control device according to the present invention.

FIG. 2 is a hardware configuration diagram of an embodiment of the position control device according to the present invention.

FIG. 3 is a flowchart of a main routine.

FIG. 4 is a flowchart of a pulse edge processing routine.

FIG. 5 is a flowchart of a reproduction operation routine.

FIG. 6 is a circuit diagram of an embodiment of a rotation direction switching unit.

FIG. 7 is a flowchart of a bounce elimination routine incorporating frequency division processing.

FIG. 8 is a perspective view of a driver's seat incorporating a DC motor.

FIG. 9 is a functional diagram of a conventionally used position control device.

FIG. 10 is a timing chart in the conventional position control device.

FIG. 11 is a detailed flowchart of pulse edge count processing.

[Explanation of symbols]

 101 ... DC drive motor 102 ... Rotation speed detecting means 103 ... Target count value setting means 104 ... Counting means 105 ... Motor control means 106 ... Edge detecting means

Claims (2)

[Claims] 1. A DC drive motor (101), a rotation speed detection means (102) for generating a pulse in synchronization with the rotation of the DC drive motor (101), and a target count value setting means for setting a target count value. (1
03) until the target count value set by the target count value setting means (103) matches the rotation speed detection means (102).
The counting means (1 that integrates the pulses output from the
04) and a motor control means (105) for rotating the direct-current drive motor (101) in the normal direction or in the reverse direction according to the signal during the forward direction integration or the backward direction integration output from the counting means (104). In this position control device, the rotation speed detecting means (102) and the counting means (10)
4), the rotation speed detection means (10
2) Detects one edge of the pulse output from the counting means (104) and detects an increment command to the counting means (104), and detects the other edge of the pulse output from the rotation speed detecting means (102) during reverse rotation. Then, the counting means (10
Edge detection means (1) that outputs a decrement command to (4)
06) is provided. 2. The change detecting means for judging whether or not there is a change in the signal of the rotation speed detecting means (102) by the edge detecting means (106), and the rotation speed detecting means (during forward rotation). Frequency division means for dividing the output of the rotation speed detection means (102) into 1/2 with reference to the other edge of the rotation speed detection means (102) during reverse rotation with reference to one edge of the rotation speed detection means (102). The position control device according to claim 1, comprising: