JP3550489B2 - MOTOR CONTROL METHOD, MOTOR CONTROLLER, AND TIME CLOCK WITH THE MOTOR CONTROLLER - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a motor control method, a motor control device, and a time clock provided with the motor control device.
[0002]
[Prior art]
An inexpensive DC motor may be used as a driving unit for pulling in a time card by a time recorder and further raising the time card to a position where it can be printed on a print column.
[0003]
In such a time clock, when a time card is inserted into the card insertion slot, this is detected by a sensor, a DC motor is driven by a control circuit, the time card is drawn to a predetermined position, and further printed according to the date data. The print head prints at a predetermined position in the column to a height at which printing can be performed and stops when the column is stopped.
[0004]
The control for starting or stopping the DC motor is performed by a control circuit. The stop operation of the motor is performed by applying a brake to the motor when the motor reaches a forward position by a predetermined distance from the stop target position. To stop at.
[0005]
[Problems to be solved by the invention]
However, there is a problem that when the DC motor is suddenly braked during high-speed rotation, an excessive force acts on the motor, resulting in low durability.
[0006]
In addition, changes in temperature and humidity change the characteristics of the motor, the paper thickness of the time card, or the characteristics of the machine itself. As a result, the load on the motor changes. Therefore, there is a problem that the rotation speed of the motor fluctuates and the stop position of the time card is shifted. This problem is not limited to the motor for a time clock, but also applies to all devices using a DC motor.
[0007]
[Means for Solving the Problems]
To solve the above problem,The motor control method according to claim 1 is a motor control method for stopping an object moved via a motor whose operation speed varies depending on a motor usage environment such as temperature or humidity at a predetermined target position. The second motor for operating the motor, which is sometimes driven under the first drive condition for operating at the first operating speed, at a second operating speed lower than the first operating speed before the target position. The motor is switched to a driving condition, a braking signal is supplied to the motor in a state where the motor is decelerated, and the object is stopped at the target position. The deceleration period for operating the motor under the second driving condition is a fixed period. The first operation speed is directly or indirectly detected, and the timing of switching from the first drive condition to the second drive condition is corrected based on the detection result. According to this,The motor that is rotating under the first drive condition is not suddenly braked just before the stop target position, and the motor is driven in the second drive condition by low-voltage drive or the like for a certain section before the brake section. At the end of the drive section under the second drive condition, a braking force is applied to stop the motor at the target position, so that no excessive force acts on the motor.
[0008]
Also,In the motor control method according to claim 2,Further, in order to accurately stop the object at the target position in response to the speed fluctuation of the motor or the like, the rotation speed of the motor rotating under the first driving condition is measured by the detecting means, and the correction amount is calculated from the average value. The calculated switching timing for switching the motor to the second drive condition is corrected.
[0009]
Correction of such switching timingAs in the motor control method according to claim 4,This is performed by detection means including an encoder that works in conjunction with the motor. This detection operation is preferably performed a plurality of times, and the reliability can be improved by employing the average value.As in the motor control method according to claim 3,Further, the accuracy of the data can be improved by using the latest data.
[0010]
According to a fourth aspect of the present invention, the motor is a recording medium transport motor for moving a recording medium such as a time card for a time recorder.
[0011]
The motor control device that performs such motor control includes a storage unit as in the motor control device according to claim 6. The storage unit includes a storage unit for operating the motor at the first operation speed in normal times. And a second drive condition for operating at a second operation speed lower than the first operation speed.
[0012]
Further, in the motor control device according to the seventh aspect, the storage means stores a plurality of correction amounts of timing for switching from the first drive condition to the second drive condition in association with the first operation speed of the motor. It has two storage circuits. In the motor control device according to the eighth aspect, the storage means further includes a third storage circuit for storing a detection result by the detection means, and the switching timing of the motor speed is organically controlled by the three storage circuits. To be performed.
[0013]
In the motor control device according to the ninth aspect, the detection unit includes an encoder that operates in conjunction with the motor, and the detection unit determines a period of the output pulse of the encoder or the first period based on the period. The operation speed is calculated.
[0014]
According to a tenth aspect of the present invention, the motor is a recording medium transport motor for moving a recording medium such as a time card for a time recorder, and the motor control device is specifically described in the eleventh aspect. When applied to the time card transport device of the time recorder, the time card can be accurately stopped at the stop target position even when an inexpensive DC motor is used, and the life of the time recorder can be extended.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, embodiments of the present invention will be described with reference to the accompanying drawings.
[0033]
【Example】
Hereinafter, as one embodiment of the present invention, a case where the present invention is applied to a motor for a time clock will be described.
As shown in FIG. 1, a roller shaft 2 is provided in the vicinity of an upper portion of a frame 1 so as to be rotatable in a horizontal posture. Pinch rollers 2a, 2a are fixed to the roller shaft 2 at positions corresponding to the vicinity of both sides of the time card C. A roller (not shown) forming a pair with the pinch rollers 2a, 2a is rotatably provided on the opposite side of the surface of the time card C facing the roller shaft 2, and the time card C is rotated by forward and reverse rotation of the roller shaft 2. Can be moved up and down. A wheel train R for transmitting rotation of a DC motor 8 to be described later to the roller shaft 2 to move the time card in the vertical direction is provided on the front left portion 1a of the frame 1.
[0034]
The configuration of the wheel train R will be described by going back from the roller shaft 2 side to the drive side.
As shown in FIG. 2, a roller shaft driving gear 3 is fixed to the roller shaft 2, and a pinion 4a integral with the first intermediate wheel 4 meshes with the driving gear. A second intermediate wheel 5 meshes with the first intermediate wheel 4, and a pinion 6a integral with the third intermediate wheel 6 further meshes with this intermediate wheel. The third intermediate wheel 6 meshes with the motor gear 7. The motor gear 7 is fixed to a motor shaft 8a of a DC motor 8 attached to a lower portion of the frame 1. Therefore, when the forward / reverse rotation of the motor 8 is transmitted to the roller shaft 2 via the wheel train R, the time card C is pulled in or pulled up.
[0035]
The second intermediate wheel 5 is provided with a rotating plate 9 concentric with the second intermediate wheel 5 so as to be integrally rotatable. The rotary plate 9 is provided with radial through holes 9a at equal intervals inside the outer peripheral portion. An interrupter-type optical sensor 10 is provided at one location near the outer peripheral portion of the rotating plate 9 so as to sandwich the rotating plate 9, and through the rotation of the rotating plate 9, a through hole 9 a allows light from the optical sensor 10 to pass. Or to shut it off. That is, the rotating plate 9 and the sensor 10 constitute a detecting unit (encoder) 16 for converting the rotation amount of the motor 8 into a pulse signal. The data signal output from the detection means 16 is output to a control circuit 15 described later.
[0036]
As shown in FIG. 1, near the upper part of the frame 1, a pair of card sensors 13, 13 constituting card detecting means are provided on both sides of the time card C, respectively.
[0037]
Here, in the time recorder of this embodiment, when a time card (standard specification product) that is optimal for the specification of the time recorder is used, since the time card is provided with print columns on both front and back sides, the user can set the time. You need to insert the card correctly. Therefore, as in the case of the time card C shown in FIG. 1, a notch C1 is provided at the upper end of the time card C, so that the front and back of the time card can be discriminated by the above-mentioned pair of card detecting means. ing.
[0038]
Also, it is not a standard specification time card but can be used (a time card in which data such as a print column is stored in advance). For example, a print column is provided only on one side instead of having print columns on the front and back. There are printheads that are provided, and printheads are provided on the front and back sides, but the positions of the printouts are different. These can also be used. In this case, it is necessary to switch the mode for the time card in advance.
[0039]
As described above, when any time card is used, when the time card is inserted from the card insertion slot, the card detecting means detects the lower end of the time card, and the time recorder starts the operation of pulling in the time card. In the case of a standard time card, the pull-in operation is such that one of the pair of card detecting means detects the upper end of the side on which the notch of the time card is provided, and the other detects the notch of the time card. Is performed until the upper end of the side where the is not provided is detected.
[0040]
Then, a threshold value is set for the difference between the detection times of the two card detection units. That is, when the time card is within the threshold value, the time card is used for the present time recorder, and it is determined that the time card has been correctly inserted. When the time is equal to or less than the threshold, the time card is a time card other than the time card for the present time recorder, but it is determined that the time card is correctly inserted, and the time card is processed according to the set mode. I have. If the time is equal to or greater than the threshold, even if the time card is for the present time recorder or another time card, it is determined that an error has occurred, and a time card ejection operation is performed as a pull-in operation error.
[0041]
Below the roller shaft 2, a print head 14 for printing the date and time and the like in a print column C2 of the time card C is provided. The print head 14 is mounted on a carrier (not shown), which also moves horizontally along a carrier feed axis (not shown).
[0042]
FIG. 3 is a block diagram showing a configuration of the motor control device. An output signal from the above-described card detecting means 13 can be input to a control circuit (CPU) 15 which forms a central portion of the motor control device. ing. The detecting means 16 is the above-described encoder, directly or indirectly measures the rotation speed (first operating speed) of the motor under normal voltage driving (first driving condition), and outputs the output signal to the control circuit 15. It can be supplied to The data calculated here is data for calculating the amount of correction of the timing of switching the motor 8 to low-speed rotation by normal voltage driving. As for the calculated data, the average value of the latest eight data is stored in the storage unit 17 described later.
[0043]
In the control circuit 15, a storage means 17 is provided so as to be able to exchange data. The storage means 17 is provided with three storage circuits for storing the print position and print content of the time card C and for storing motor control data to be described later.
[0044]
The control circuit 15 can process the various data described above and output the result to the motor drive circuit 18. The motor drive circuit 18 receives the command signal from the control circuit 15, switches the drive voltage just before the stop target position, decelerates the motor 8, and then supplies a brake signal to the motor 8 to move the time card to the stop target position. It works to stop. The rotation of the motor 8 is detected by detection means 16 such as an encoder, and control for switching the drive voltage of the motor is performed based on the detection result.
[0045]
Here, three storage circuits provided in the storage unit 17 will be described.
The first storage circuit 17a stores two driving conditions for controlling the speed of the motor 8. As a first condition, a condition (first drive condition) for driving the motor 8 at a normal voltage to rotate the motor 8 at a normal rotation speed (first operation speed) at the time of, for example, a pull-in operation or a pull-up operation of a time card is stored. I have. The second condition is that the motor is driven at a rotation speed lower than the first operation speed (second operation speed) at a position before stopping the motor (second operation speed) (the second driving condition). Is stored.
[0046]
When the control circuit 15 reads the first drive condition from the first storage circuit 17a and outputs a command signal to the motor drive circuit 18, the motor 8 rotates at the first operation speed to perform a time card pull-in operation. When reaching the end position of the pull-in operation, the control circuit 15 switches from the first drive condition to the second drive condition and rotates at a speed lower than the normal rotation speed (second operation speed) for a certain period (deceleration period). ) Is set to move only. After the elapse of the deceleration period due to the second operation speed, a braking signal can be supplied to the motor 8 to stop at the target position (see FIG. 4). The deceleration period is set to be constant.
[0047]
The second storage circuit 17b stores data for coping with a change in the first operation speed due to a change in the use environment of the motor such as temperature and humidity when the motor 8 is rotating under the first drive condition. Is stored. This is because even if the motor 8 is driven under the same first driving condition, the first operating speed fluctuates due to a change in the use environment. Therefore, the motor 8 is stopped only by the data stored in the first storage circuit 17a. It is known that the position cannot be controlled correctly, and data necessary for coping with this is stored. That is, assuming that the rotation speed of the motor 8 is high even under the same first driving condition due to a change in temperature, humidity, or the like, the time is not changed from the first driving condition to the second driving condition before the stop target position. The card will overrun the stop target position. Conversely, when the rotation speed of the motor is low, the motor stops before reaching the stop target position. The second storage circuit 17b associates a plurality of correction amounts of timing for switching from the first drive condition to the second drive condition with respect to a change in the first operation speed caused by a change in the use environment to the above-described first operation speed. To remember.
[0048]
The third storage circuit 17c stores a detection result by the detection means (encoder) 16. The detection result by the encoder 16 is configured to store the detection result of a plurality of times, and the third storage circuit 17c has a storage area for that, and the control circuit 15 can read out the data in association with the first operation speed. It has become. The storage area always stores a plurality of predetermined latest detection results, for example, the latest eight data, and sequentially updates the data from the oldest one. As a result, the timing of switching from the first driving condition to the second driving condition can always be set based on the latest data, whereby the latest eight data before the upper end detection of the card can be obtained, The detection location is constant.
[0049]
Since the detection result stored in the third storage circuit 17c may reduce the reliability of the switching timing when the motor 8 fluctuates in speed, the average value of the latest plurality of detection results may be calculated. A storage area for storing is further provided.
[0050]
[Description of operation]
In FIG. 4, the horizontal axis indicates the amount of rotation of the DC motor by the number of light beams, that is, the number of pulses of the sensor passing through the through hole 9a (see FIG. 2) of the rotary plate 9 of the encoder, and the vertical axis indicates the motor speed (rotation speed). Speed), and each curve shows a change in speed from the start of the motor until the motor stops. The curve shown by a solid thick line indicates a certain operating condition (hereinafter, this condition is referred to as a “normal state”). ), Where the solid thin curve is slower than the normal speed, and the thin broken curve is faster than the normal speed.
[0051]
First, a description will be given of the case of the speed in the normal state shown by the solid thick line. A minute time elapses during the acceleration after the motor starts, and the normal voltage driving (the first driving condition) is performed while moving the time card from a certain time point d0. )) (First operation speed). After the motor is rotated at a constant speed by the normal voltage and the time card is moved by the section A, a speed by the low-voltage driving (second driving condition) at a position d2 a predetermined distance before the stop target position d1 (second operating speed). ) And move only by section B. At this time, the rotation speed of the motor is N1 at the time of the normal voltage, but becomes N2 when the section B is completed by deceleration by the low voltage driving. This section B is a deceleration period due to switching to low-voltage driving, and this period is set to be constant in an initial state.
[0052]
At a position d3 where the time card C has passed the section (deceleration period) B due to the low voltage driving of the motor 8, the circuit of the motor is switched to supply a braking signal to the motor to apply a brake and stop at the stop target position d1. Let it. The brake is applied by supplying a braking signal to the motor. Specifically, the circuit of the motor is switched to generate a torque in the reverse direction to the motor, and the motor works by canceling the torque due to the inertial force of the motor and this torque.
[0053]
When the motor is stopped in this manner, if the actual rotation speed of the motor is in accordance with the basic setting, the control circuit does not need to correct the drive voltage switching timing and the brake timing. However, in reality, the environment in which the time card is used is constantly changing, and the rotational speed of the motor changes accordingly. Therefore, it is necessary to correct these timings.
[0054]
Next, the operation for correcting such a timing will be described with reference to the flowchart shown in FIG.
FIG. 5A shows a control procedure in a time card pull-in operation. First, when a time card is inserted into the card slot of the time clock (S1), the sensors 13 and 13 of the card detecting means are shielded from light (S2), and the fact that the time card has been inserted is output to the control circuit 15. . Upon receiving this signal, the control circuit 15 drives the motor 8 by the motor drive circuit 18 to draw in the time card (S3). At this time, since the rotating plate 9 of the encoder 16 serving as the detecting means is also interlocked with the rotation of the motor 8, the light emitted from the light emitting element of the optical sensor is read using the light receiving element through the through hole 9a of the rotating plate. Is converted into a pulse signal and output to the control circuit 15. The pulse signal is used by the control circuit 15 to calculate the cycle of the motor rotation speed, and only the latest eight data of these cycles are stored in the third storage circuit 17c of the storage means 17 (S4).
[0055]
Further, the operation of pulling in the time card C continues. In this time zone, the presence of the time card is constantly detected by the sensors 13 and 13 of the card detecting means. At this time, the speed measurement by the encoder 16 is continued until one of the left and right card detection sensors transmits light, and the data is updated while only the latest eight data are always stored in the third storage circuit 17. Is performed.
[0056]
The updating of the data is continued until the right or right sensor transmits light (S5), and the upper end of the card is detected by the transmission. After the upper end of the card is detected, the drawing operation is further continued and both sensors transmit light (S6), so that it is determined whether or not the time card has been correctly inserted (S7).
[0057]
In this determination, one of the pair of card detection sensors 13, 13 detects the upper end of the cutout portion C1 of the time card, and the other sensor detects the upper end of the cutout portion of the time card within the threshold value. When the upper end is detected (that is, both sensors are through holes), a predetermined feed stop operation is started.
[0058]
Prior to the start of the feed stop operation, if the difference between the detection times of the sensors 13 and 13 is within the above-described threshold value, it is determined that the time card C of the standard specification of the present time recorder is correctly inserted. If the difference between the detection times is equal to or smaller than the threshold, it is determined that other time cards are correctly inserted. On the other hand, when the difference between the detection times is equal to or greater than the threshold value, it is determined that an error has occurred in the time card of any specification, and the time card ejection operation is performed as a pull-in operation error process. If the time card C is not properly inserted, such as the specifications or the front and back sides, the ejection operation of the time card is performed as an erroneous insertion (S8), and the same operation is repeated by re-inserting the time card having the correct specifications on the correct side. It is.
[0059]
If it is determined that the insertion of the time card C is correct, the average value z of the eight data obtained by measuring the period of the encoder and the correction amount based on the z are calculated (S9). This correction amount is how much distance (pulse) should be shifted from the basic setting at the timing of switching the rotation of the motor from the normal voltage drive to the low voltage drive, and a and b in FIG. 4 correspond to this. I do.
[0060]
For example, as shown by the broken line in FIG. 4, when the rotation speed of the motor in the normal voltage section is faster than the set value, the switching operation of the basic setting is shifted by a before the distance d2 to start the stop operation. It shows that it moves to. Also, as shown by the solid thin line, when the rotation of the motor is slower than the set value, the motor can be stopped at an accurate position by switching to low voltage driving at a position shifted by b after d2. It is assumed that.
[0061]
When the switching timing d2 for switching to the low-voltage driving is determined in this way, the rotation speed of the motor is switched to the low-voltage driving, and the time card is drawn in the B section by the low-speed rotation (S10).
[0062]
When the time card is pulled to the position d3 where the brake can be applied by the low voltage drive, the circuit of the motor drive circuit 18 is switched to apply a reverse voltage (braking voltage) to the motor 8, and a reverse torque is applied. To stop at the stop target position d1 (S11). The length of the brake section C is 150 msec in the basic setting. When the time card stops at the target position, the preparation operation for printing on the time card is completed, and the process shifts to time card positioning control (S12).
[0063]
FIG. 5B is a flowchart showing the operation of the time card positioning control. As described above, the insertion of the time card is determined by the pulling-in operation of the time card, and when the time card is stopped at the stop target position d1, the process proceeds to a time card pull-up start operation (S21).
[0064]
At the time of the pulling operation, the rotation of the motor 8 is in the opposite direction to that at the time of the pulling operation, and the time card C is pulled up by the pinch rollers 2a, 2a (see FIG. 1). At this time, the notch C1 formed on one side of the upper end of the time card C rises to a position crossing the sensor 13 of the card detecting means, and the other side shields the other sensor 13 so that the time card C The upper end is detected (S22). This operation is continued until the upper end position of the time card is detected during the rising operation of the time card, and when the upper end is detected, the start position of the stop operation for stopping at the correct position in the predetermined print column C2. (S23). The stop operation start position corresponds to a switching timing d2 for switching to low-voltage driving during the pull-in operation. Therefore, also in this case, the rotation speed of the motor during the lifting operation is measured by the encoder, and the average value z (small letter) of the eight measured values and a correction amount based on this z are calculated. If it is faster than this, the timing is corrected so as to be earlier, that is, in the direction of a shown in FIG. 4, and if it is later, this timing is corrected so as to be later, that is, corrected in the direction of b shown in FIG. The stop operation is started from the position where the operation is performed.
[0065]
The stop operation switches the rotation of the motor from the normal voltage drive to the low voltage drive, raises the time card by the low voltage drive in a certain section (section B) (S24), ends the movement in section B, and ends this section. When the motor reaches the position d3, the circuit is switched to apply a reverse voltage (braking voltage) to the motor, move the section C while applying the brake (S25), and stop at the stop target position d1. The printing step is determined (S26). These series of stop operations are performed based on the calculated value of the correction amount, as in the pull-in operation.
[0066]
When the printing stage is determined, printing of the time and the like is performed at the printing position positioned by the printing head 14. After printing, the time card is pulled up to a position where it can be extracted by the pinch rollers 2a.
[0067]
Although the above description of the configuration and operation has been made with respect to the transport motor that moves the recording medium such as the time recorder and the time card used therein, the present invention is not limited to the motor for the time recorder, but may be applied to a DC motor that moves an object. The control is generally applicable. By adopting the present invention, an object can be stopped at an accurate position by using an inexpensive DC motor, so that an expensive step motor does not have to be used.
[0068]
In the above embodiment, the rotation speed of the motor is changed by the voltage control method. However, the present invention is not limited to this, and the speed control may be performed by a well-known frequency control method or duty control method. .
[0069]
Further, the present invention is not limited to a time recorder, but is applicable to all devices using a DC motor as a power source, and the recording medium is not limited to a time card. For example, ordinary printing paper, a magnetic card, or an IC card And the like can be applied.
[0070]
【The invention's effect】
According to the present invention, in order to stop the moving object at the stop target position at the first operation speed, a predetermined section is previously switched to the second operation speed, ie, the rotation speed of the motor driven by the low voltage, and the rotation speed is reduced. By applying a brake after stopping the motor, the motor is prevented from being subjected to an excessive force, thereby improving the durability of the motor.
[0071]
Further, since the deceleration period for operating the motor under the second drive condition is a fixed period, the timing of starting the motor stop operation can be simplified.
[0072]
Further, the rotation speed of the motor under the first driving condition is measured by the detecting means, and the timing of switching from the first driving condition to the second driving condition is corrected based on the measured value. Times and based on the average value, and furthermore, the correction is based on the average value using the latest multiple times of the multiple measurements, so that the start timing of the motor stop operation is determined. Is corrected, it is possible to stop at an accurate position even when the rotation speed of the motor fluctuates due to an external factor.
[0073]
Further, the detecting means for measuring the rotation speed of the motor detects output pulses from an encoder integrally formed in the middle of a wheel train provided from the motor to an action portion for moving the recording medium. Therefore, the target measurement can be performed without providing any special detecting means.
[0074]
Further, if the present invention is applied to the control of the motor for transporting the time card of the time recorder, the time card can be stopped at an accurate position and printed by an inexpensive DC motor, thereby contributing to a reduction in the manufacturing cost of the time recorder. .
[Brief description of the drawings]
FIG. 1 is a front view showing an example of the internal configuration of a time clock to which the present invention is applied.
FIG. 2 is a side view of the same.
FIG. 3 is a block diagram showing a configuration of the present invention.
FIG. 4 is a diagram showing a relationship between a movement amount of a time card and a rotation speed of a motor.
FIG. 5 is a flowchart illustrating a control operation of a time card.
[Explanation of symbols]
C time card
8 motor
13 Card detection means
15 Control circuit
16 Detecting means (encoder)
17 Storage means
17a first memory circuit
17b Second memory circuit
17c Third memory circuit
18 Motor drive circuit

Claims (11)

A motor control method for stopping an object moved via a motor whose operating speed fluctuates depending on a motor usage environment such as temperature or humidity at a predetermined target position,
The motor, which is driven under the first drive condition for operating at the first operation speed at normal time, is operated at a second operation speed lower than the first operation speed before the target position. Switch to 2 driving conditions,
A brake signal is supplied to the motor in a state where the motor is decelerated to stop the object at the target position ,
The deceleration period during which the motor is operated under the second drive condition is a fixed period, and the first operation speed is directly or indirectly detected. A motor control method, wherein a timing for switching to a driving condition is corrected . 2. The motor control method according to claim 1, wherein the detection result is obtained by averaging detection values of a plurality of predetermined detection operations. 3. The motor control method according to claim 2, wherein the detection result is obtained by averaging detection values of a plurality of predetermined detection operations performed immediately beforehand. 4. The method according to claim 1, wherein the detection of the first operation speed is performed by detecting a cycle of an output pulse of an encoder linked to the motor or calculating the cycle based on the detected cycle. 5. Motor control method. The motor control method according to any one of claims 1 to 4, wherein the motor is a recording medium transport motor for moving a recording medium such as a time clock time card. A motor control device for stopping an object moved via a motor whose operating speed fluctuates depending on a motor usage environment such as temperature or humidity at a predetermined target position,
  A first storage in which a first drive condition for operating the motor at the first operation speed and a second drive condition for operating the motor at a second operation speed lower than the first operation speed in a normal state are stored. Storage means having a circuit;
  The driving condition of the motor is switched from the first driving condition to the second driving condition before the target position by a signal from the control circuit to decelerate the motor, and thereafter, a braking signal is supplied to the motor. A motor drive circuit for stopping the object at the target position,
Detecting means for directly or indirectly detecting the first operation speed;
  With
A motor control device, wherein a deceleration period for operating the motor under the second drive condition is a fixed period, and a timing for switching from the first drive condition to the second drive condition is corrected based on the detection result. The storage unit further includes a second storage circuit that stores a plurality of correction amounts of timing for switching from the first drive condition to the second drive condition in association with the first operation speed of the motor. The motor control device according to claim 6, wherein: The storage unit further includes a third storage circuit that stores a detection result obtained by the detection unit. The third storage circuit includes a storage area that stores a plurality of detection values obtained by the detection unit. 8. The motor control device according to claim 7, wherein a plurality of predetermined detection values are averaged to obtain the detection result. 9. The method according to claim 6, wherein the detecting means includes an encoder that operates in conjunction with the motor, and calculates the first operation speed based on a cycle of an output pulse of the encoder or the cycle. The motor control device according to any one of the above. 10. The motor control device according to claim 6, wherein the motor is a recording medium transport motor for moving a recording medium such as a time clock time card. A motor control device according to claim 10 is provided. Time clock.

Images