JPH10323089A - Controller and control method for printer motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller and control method for a printer motor capable of accurately adjusting the moving speed of a printing head and improving printing quality by adjusting the variation time interval of a motor control signal with an accuracy several times higher than the accuracy of a CPU timer. SOLUTION: This printer refers to a rotation trigger signal 13 generated by a CPU11 and its motor driver 19 rotates and drives a carriage (CR) motor 21 by the motor driver control signals 38, 39 generated by a motor driver control section 15. In this case, the motor driver control section 15 contains a motor driver signal generating circuit 15A, a motor driver drive mode setting register 15B, a block revolution setting register 15C, and a step time setting table 15D during block rotation, and the motor driver control signals 38, 39 are sequentially changed at least by n step (n>=2 as integer) for one rotation trigger signal 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device and a control method for a motor for a printer, and more particularly to a control device for a motor for a printer capable of increasing the printing speed of a printer and improving the printing quality. And a control method.

[0002]

2. Description of the Related Art A plurality of types of motors such as a carriage (CR) motor, a paper feed (PF) motor, and a platen gap adjustment motor are used in a printer. Generally, these motors are rotationally driven by motor currents generated by respective motor drivers, and each motor driver is controlled by a control signal output from a motor driver control unit or the like.

On the other hand, the rotation of these motors needs to be controlled in a control mode corresponding to each purpose, such as printing, carriage movement, or other mechanical purposes.

In addition, for example, in the rotation of a motor for printing, it is necessary to flexibly change the rotation operation state in accordance with a mechanical environment such as a remaining amount of ink and a head temperature.

FIG. 5 shows an example of such a conventional printer motor control.

In the printer shown in FIG.
The rotation of the rotation shaft causes the belt 52 to move left and right, and the carriage 53 fixed to the belt 52 and the print head 54 fixed to the carriage 53 move left and right on the printing paper 55. The printing is executed while performing the printing. The rotation control of the CR motor 51 is generally performed using a CPU 57 having a timer 56 built therein.
While the time is managed in real time by the built-in timer 56 of the PU 57, the rotational operation state of the CR motor 51 is controlled. Further, at the timing when the print head 54 has moved to a position on the printing paper 55 where printing is to be performed, the print head 5 is moved.
4 for time management of a series of printing sequences, such as time management for sending an ink ejection control signal 58 to the CP 4.
A built-in timer 56 of U57 is used.

In the above-described control of the CR motor 51, a control signal of the CR motor 51 is conventionally synchronized with an interrupt process of the CPU 57 which is generated every time the time set in the built-in timer 56 of the CPU 57 elapses. By changing the rotation mode, the rotation driving mode of the CR motor 51 (2-2)
Phase drive, 1-2 phase drive, W1-2 phase drive, etc.).

FIG. 6 shows a timing flow of an operation when printing is performed by using the built-in timer of the CPU.

That is, this shows a state in which the CR motor 51 rotates while the state of the motor control signal 60 changes for each interruption process 59 by the CPU. CR motor 51
With the rotation of the print head 54, the print head 54 moves on the print paper 55, and the print data 61 is printed on the print paper 55 at the position where the ink ejection control signal 58 becomes active.

[0010]

In order to improve the printing speed and printing quality of a printer, it is necessary to precisely control the current flowing through various motors for the printer in smaller time units. For this purpose, it is necessary to precisely control the motor driver control signal for controlling the motor driver that generates the motor current described above in smaller time units.

Hereinafter, a problem of so-called color adjustment will be described as an example.

FIG. 7 shows a print head 54 for ejecting ink.
The schematic structure of is shown. Here, a description will be given assuming that there are two nozzle rows on the print head 54, a nozzle row 71 and a nozzle row 72. Each of the nozzle rows 71 and 72 has a nozzle 7
3, a plurality of nozzles such as the nozzle 74 are arranged. In addition, the nozzle row 71 and the nozzle row 72 are spaced apart from each other by a predetermined distance 75 in design. For example, when color printing is performed using the print head 54 shown in FIG. 7, different colors of ink are assigned to the nozzle rows 71 and 72, and these inks are attached to the same position to perform color synthesis. . That is, as shown in FIG. 8, when the print head 54 is at the position (A), ink is ejected from the nozzle row 72, and when the print head 54 comes to the position (B), By ejecting the ink from the nozzle row 71, the ink of the nozzle row 72 and the ink of the nozzle row 71 of a different color are ejected to the print position 76 of the printing paper 55, and the colors are combined, so that color printing is possible. Becomes

If the diameter of the rotary shaft of the CR motor 51 of the printer varies, for example, the moving speed of the print head 54 changes depending on the type of the printer. It is difficult to perform ink ejection to the same position with high accuracy. Therefore,
In order to correct the moving speed of the print head 54 due to such mechanical variation, it is necessary to adjust the time interval for changing the control signal of the CR motor 51 in a shorter time unit.

However, in the above-described conventional control method shown in FIG. 5, the built-in timer 56 of the CPU 57 uses one of the clocks 81 input from the oscillation circuit 80 to the CPU 57.
Since the clock time is set to the minimum time unit, the time interval for changing the control signal 60 of the CR motor 51 cannot be adjusted in a shorter time unit.

In the conventional control method, the CPU 57 needs to manage the motor control every time the motor control signal 60 changes, so that the moving speed of the print head 54 can be increased to increase the printing speed. CPU5
7 increases the rate of being called out for controlling the CR motor 51, and this causes an obstacle, so that the printing speed as a whole cannot be increased.

An object of the present invention is to precisely adjust the moving speed of the print head by adjusting the change time interval of the motor control signal with a multiple of the accuracy of the CPU timer, and to improve the print quality. An object of the present invention is to provide a printer motor control device and a control method that can be improved.

Another object of the present invention is to increase the moving speed of the print head without increasing the rate at which the CPU is called to change the motor control signal.
An object of the present invention is to provide a control device and a control method for a printer motor that can improve the printing speed as a whole.

[0018]

In order to achieve the above object, a control device and a control method for a printer motor according to the present invention use a motor control signal generated by referring to a rotation trigger signal generated in connection with a CPU. In the control of the printer motor for controlling the rotation of the motor, the motor control signal is sequentially changed by at least n (n is an integer of n ≧ 2) steps in response to one rotation trigger signal.

That is, according to the first aspect of the present invention, in the printer motor control device for controlling the rotation of the motor by the motor control signal generated by referring to the rotation trigger signal generated in relation to the CPU, The motor control signal is sequentially applied to the rotation trigger signal at least for n times.
(N is an integer greater than or equal to 2).

One rotation trigger signal output in connection with the CPU causes the motor control signal to be at least n
(N is an integer of n ≧ 2) step output,
The rotation speed can be adjusted with an accuracy of n times the unit time of the U timer.

Further, the rate at which the CPU is called for motor control is calculated during the period when the print head is actually moving, and can be reduced to (1 / n) times of the conventional method. Can be improved.

Further, in the invention according to claim 2, further, a means for setting each step time of the n steps and a value of the number of steps n for changing the motor control signal with respect to the one rotation trigger signal are further provided. Setting means.

Further, the invention according to claim 3 is characterized by further comprising means for changing the value of the number n of steps for changing the motor control signal in response to the one rotation trigger signal.

Thus, the state of the motor control signal can be flexibly changed according to the printing speed and the like.

On the other hand, the invention according to claim 4 is characterized by further comprising means for presetting a motor control state corresponding to each of the n steps.

According to a fifth aspect of the present invention, the printer motor is a carriage motor.

Further, the invention according to claim 6 is characterized in that the change in n steps is performed during the constant speed driving of the carriage.

Further, the invention according to claim 7 is characterized in that the value of n is changed according to the moving speed of the carriage.

Thus, for example, when the carriage is moved at a high speed, the value of n is increased, and when the carriage is moved at a low speed, the value of n is decreased.

[0030] The invention according to claim 8 is characterized in that the rotation trigger signal is generated by counting up a timer operating in connection with the CPU.

On the other hand, the invention according to claim 9 has a plurality of modes for changing the motor control signal by n (n is an integer of n ≧ 1) steps in response to one rotation trigger signal generated in relation to the CPU. Thus, a printer motor control device for controlling the rotation of the motor is characterized in that it has a switching means for arbitrarily switching the plurality of modes.

Thus, for example, in a state in which the rotation speed is low, a mode in which the motor control signal is changed by one step in response to one rotation trigger signal is selected to enable flexible motor control, and a constant rotation speed is maintained. In the high speed state, by switching to a mode in which the motor control signal is changed by a plurality of steps in response to one rotation trigger signal,
The motor rotation speed can be adjusted with a multiple of accuracy higher than that of the conventional CPU timer. Further, by switching the mode, the number of steps of the motor control signal can be arbitrarily changed from a plurality of steps to a plurality of steps for one rotation trigger signal.

[0033]

Embodiments of the present invention will be described below in detail with reference to the drawings.

In the present embodiment, the control device according to the present invention is applied to control of a carriage motor composed of a permanent magnet type or hybrid type two-phase stepping motor for a serial printer.

That is, the control device according to the present embodiment is provided in a printer controller of a serial printer (not shown), and as shown in FIG. This is applied to an example in which the motor driver 19 drives the carriage (CR) motor 21 to rotate in response to the motor driver control signals 38 and 39 in which occurs.

Hereinafter, a specific configuration of the control device according to the present embodiment will be described.

The CPU 11 receives the clock 23 supplied from the first transmission circuit 22 and executes a printing operation using the program stored in the ROM 25 and the RAM 27. Printing head 54 (see FIG. 5)
Is moved by the rotation of the CR motor 21, and the CR motor 21 is rotated by the two-phase current of the A-phase current 33 and the B-phase current 34 from the motor driver 19. The motor driver 19 is controlled by an A-phase current control signal group 38 and a B-phase current control signal group 39 from the motor driver control unit 15, and changes to the state of the A-phase current control signal group 38 and the B-phase current control signal group 39. Accordingly, 2-2 phase drive, 1-2 phase drive,
The CR motor 21 is rotationally driven while using various driving methods such as W1-2 phase driving. Inside the CPU 11, there is a CPU timer 12, and the CPU timer 12
2 is supplied with the clock 23, and the timer time is measured.

As shown in FIG. 2, the motor driver control unit 15 includes a motor driver control signal generation circuit 15A, a motor driver driving mode setting register 15B, a block rotation speed setting register 15C, and a step time setting during block rotation. And a table 15D. The motor driver control signal generation circuit 15A operates with the minimum time unit determined by the clock 42 supplied from the second oscillation circuit 40. In addition, the motor driver control signal generation circuit 15A uses the clock 42 supplied from the second oscillation circuit 40 to output the A-phase current control signal group 3
8 and a B-phase current control signal group 39 are generated, and these signals are supplied to the motor driver 19. Here, the motor driver control signal generation circuit 15A includes a motor driver drive mode setting register 15B, a block rotation speed setting register 1
5C, step time setting table 15 for block rotation
Motor driver control signal groups 38 and 39 corresponding to the state D are generated in synchronization with the rotation trigger signal 13 from the CPU 11.

The motor driver A-phase current control signal group 3
8 includes an A-phase control signal CRAPH, an A-phase current value control signal CRA1 and CRA0, and an A-phase reference voltage signal VREF_A, and the motor driver B-phase current control signal group 39 includes a B-phase control signal CRBPH and a B-phase current. It includes the value control signals CRB1 and CRB0 and the B-phase reference voltage signal VREF_B. A phase control signal C
The RAPH and B phase control signals CRBPH are signals for controlling the directions of the A phase current 33 and the B phase current 34, respectively.
The A-phase current value control signals CRA1 and CRA0 and the B-phase current value control signals CRB1 and CRB0 are
3. Digitally setting the current value of the B-phase current 34 to 1 (full)
l), signals determined as 2/3, 1/3, A-phase reference voltage signal VREF_A, B-phase reference voltage signal V
REF_B is a signal that determines the absolute value of the current of the A-phase current 33 and the current of the B-phase current 34, that is, the current value at the time of full.

In the control device according to the present embodiment, when the block rotation mode is set in the motor driver drive mode setting register 15B, one rotation trigger signal 13 from the CPU 11 is given n steps (n ≧ 2). Of the CR motor 21 is automatically generated from the motor driver control signal generation circuit 15A, and the CR motor 21 is rotated n steps (n ≧ 2), that is, a plurality of steps.

That is, when the block rotation mode is set in the motor driver drive mode setting register 15B, the motor driver control signal generation circuit 15A
In response to one rotation trigger signal 13 from 11, the motor driver control signal groups 38 and 39 having the number of steps set in the block rotation number setting register 15C are set in the step time setting table 15D for block rotation. It is sequentially generated at the specified time intervals and output to the motor driver 19. The CPU 11 controls the block rotation speed setting register 15C.
The rotation trigger time to be output next is set from the block rotation speed and the step time interval in the block rotation mode set in the block rotation step time setting table 15D set in the motor driver. It is output to the control unit 15.

The operation of the control device according to the present embodiment will be described with reference to FIGS.

In the present embodiment, the CR motor 21 starts rotating from a stopped state, accelerates the rotational speed, performs a constant-speed rotation drive for printing, and then reduces the rotational speed. Applied to a sequence of stops. In a state in which the rotation speed is low, a mode in which the motor driver control signal group 38 or 39 is changed by one step in response to one rotation trigger signal 13 from the CPU 11 is used, and ink ejection for printing is performed. In the constant speed state where the rotation speed is high, a mode is used in which the motor driver control signal group 38 or 39 is changed by a plurality of steps for one rotation trigger signal 13.

First, in the initial state, the CR motor 21
Means that the rotation is stopped.

Here, before starting the control for starting the rotation of the CR motor 21, the CPU 11 performs the processing of (S1) shown in FIG. That is, the CPU 11 issues a signal 16 for setting an internal register to the motor driver drive mode setting register 15B, and outputs the motor driver drive mode setting register 15B to the motor driver in response to one rotation trigger signal 13 from the CPU 11. Control signal group 38, 39
Is set to a mode in which a signal for changing the state of the above by one step is output from the motor driver control signal generation circuit 15A. Further, the CPU timer 12 is provided with a time T0 for maintaining the motor control state J0 (see FIG. 3A) before the rotation of the CR motor 21 and starts the counter of the CPU timer 12.

By the (S1) processing, the state of the motor driver control signal groups 38 and 39 becomes the J0 state, and FIG.
As shown in (a), the J0 state is held until the count-up time T0 of the CPU timer 12. CPU timer 12
As a result, the rotation trigger signal 13a is input to the motor driver control signal generation circuit 15A, and upon receiving the rotation trigger signal 13a, the motor driver control signal generation circuit 15A performs only one step as shown in FIG. The motor driver control signal groups 38 and 39 changed to the J1 state are generated and supplied to the motor driver 19,
The motor driver 19 responds to this J1 state signal by
The motor 21 is driven to rotate. In addition, the CPU 11 performs the process of (S2) shown in FIG. That is, the CPU 11 enters the time T1 for holding the motor control state J1 into the CPU timer 12, and starts the counter of the CPU timer 12.

By this (S2) processing, after T1 time, C
The PU timer 12 counts up and the rotation trigger signal 1
3b is input to the motor driver control signal generation circuit 15A, and the motor driver control signal generation circuit 15A receives the rotation trigger signal 13b, as shown in FIG.
Further, a group of motor driver control signals 38 and 39 changed by one step into the J2 state are generated and supplied to the motor driver 19, and the motor driver 19 rotates the CR motor 21 according to the signal in the J2 state. . Also, CP
U11 sets the time T2 for holding the motor control state J2 to C
It enters the PU timer 12 and starts the counter of the CPU timer 12.

Thereafter, the above control operation is repeated until the CR motor 21 reaches a predetermined motor control state Jn (see FIG. 3B). Control signal group 3
By advancing the states of 8, 39 one by one, C
The R motor 21 is driven to rotate. At this time, by gradually shortening the interval at which the rotation trigger signal 13 is output from the CPU 11, the motor driver control signal groups 38, 3
9, the step interval becomes shorter, and the rotational speed of the CR motor 21 becomes faster.

When the rotation of the CR motor 21 is accelerated as described above and the rotation speed of the CR motor 21 reaches a predetermined speed, the motor driver drive mode setting register 15B
Is set to the block rotation mode. The predetermined speed for changing to the block rotation mode may be set in advance as a control program in the ROM 25.

That is, when the motor control state Jn is reached, the CPU 11 performs the processing of (S3) shown in FIG. 3B. First, the CPU 11 outputs the signal 1 for setting the internal register.
6 is issued to the motor driver drive mode setting register 15B, the block rotation speed setting register 15C, and the step time setting table 15D. In response to the internal register setting signal 16, the motor driver drive mode setting register 15 B receives one rotation trigger signal 1 from the CPU 11.
3 is set to a mode in which a control signal change in a plurality of steps is output from the motor driver control signal generation circuit 15A. In addition, the block rotation number setting register 15C includes:
For example, 4 is set as the value of the number of steps n. Furthermore, the holding time of each step (Jn + 1 state holding time, J
(n + 2 state holding time, Jn + 3 state holding time) are set in the block rotation step time setting table 15D. The holding time of the Jn + 4 state is determined by the time set in the CPU timer 12 set in the S4 process.

In FIG. 3B, the CPU 11 executes the process (S3) in the Tn period immediately before the Tn + 1 period that actually enters the operation mode in which a plurality of steps are changed, and the first rotation trigger at which Tn + 1 is started. The respective states of the motor driver drive mode setting register 15B, the block rotation speed setting register 15C, and the step time setting table 15D are synchronized with the signal 13e.
A, and as shown in FIG. 3 (b), the motor driver control signal group 3
The operation of changing 8 and 39 four times is started.

Motor driver control signal generation circuit 15A
Are based on various setting states taken in synchronization with the rotation trigger signal 13e.
9 is changed to Jn + 2, Jn + 3, and Jn + 4 after the holding time of each step, as shown in FIG. J
The state changes from the n + 4 state to the Jn + 5 state when the next rotation trigger signal 13f is input. Therefore, T
In the S4 process performed at the beginning of the n + 1 period, the CPU timer 12 is set to Tn + 1 time.

Here, the S4 process performed by the CPU 11 will be described. Tn + 1 time (Jn + 1 state holding time + Jn + 2 state holding time + Jn + 3 state holding time + Jn + 4 state holding time) is input to the CPU timer 12. Next Tn + 2
The holding time of each step in the period is set in each step time setting table 15D (Jn + 5 state holding time, Jn + 6 state holding time, Jn + 7 state holding time,
The Jn + 8 state holding time is determined by the time set in the CPU timer 12 set in S5 processing described later.

Subsequently, the motor driver control signal groups 38 and 3 are supplied by the rotation trigger signal 13f input by the time-up of the CPU timer 12 after Tn + 1 time.
The state of 9 becomes the Jn + 5 state, and the CPU 11 performs the S5 process.

Here, the S5 process performed by the CPU 11 will be described. Tn + 2 time (Jn + 5 state holding time + Jn + 6 state holding time + Jn + 7 state holding time + Jn eighteen state holding time) is input to the CPU timer 12. Next Tn + 3
The retention time of each step in a period (not shown) is set in each step time setting table 15D.

Thereafter, by repeating the same operation, the rotation of the CR motor 21 is controlled so that the motor driver control signals 38 and 39 change four times for one rotation trigger signal 13. Will be

As described above, the motor driver control signal group 3
The CPU timer 1 sets the time corresponding to 4 steps of changes in 8 and 39.
2 which is 4 times higher than the conventional CR
The rotation speed of the motor 21 can be adjusted. Further, the rate at which the CPU 11 is called to change the state of the motor driver control signal groups 38 and 39 from the CPU 11 is 1/4 of the conventional rate, assuming that the change speed of the state of the control signal groups 38 and 39 is the same. Since the time allocated to other data processing increases, it is possible to improve the total printing speed and shorten the throughput by the printer to which the control device of the present embodiment is applied.

When the printing operation performed by rotating the CR motor 21 at a constant speed is completed, the rotation speed of the CR motor 21 starts to decrease, and when the rotation speed is reduced to a predetermined speed, the CR motor 21
The rotation control of the control exits from the block rotation mode described above in synchronization with the rotation trigger signal 13 from the CPU 11,
The mode returns to the mode in which the motor driver control signal group 38 or 39 is advanced by one step in response to one rotation trigger signal 13 from the PU 11. The predetermined speed for exiting from the block rotation mode can also be set in advance as a control program in the ROM 25. And C
By gradually increasing the interval at which the rotation trigger signal 13 is output from the PU 11, the step interval of the motor driver control signal groups 38 and 39 is increased, and the rotation speed of the CR motor 21 is reduced, and finally stopped. Is done.

As described above, in the present embodiment, in a state where the rotation speed is low, the mode in which the motor driver control signal group 38 or 39 is changed by one step in response to one rotation trigger signal 13 from the CPU 11 is set. In the constant speed state where the rotation speed is high and ink jetting for printing is performed, a mode in which the motor driver control signal group 38 or 39 is changed by a plurality of steps for one rotation trigger signal 13 is selected. be able to. Accordingly, in a state where the rotation speed is low, the CPU can manage the rotation control of the CR motor 21 for each step change, so that flexible motor control becomes possible. On the other hand, when the rotation speed is high, the rotation speed of the CR motor 21 can be adjusted with an accuracy four times higher than the accuracy of the conventional CPU timer, so that the printing quality can be improved. Further, since the ratio at which the CPU 11 is called is 1/4 of the conventional rate, the time allocated to other data processing is increased, so that the printing speed can be improved and the throughput can be reduced.

FIG. 4 is a flowchart showing a control procedure by the control device according to the present embodiment.

First, the CPU timer 12 starts (S
101), it is determined whether to change the mode setting (S102). When changing the mode setting, the mode is changed (S103). Here, the mode change means, for example, a change in the number of set automatic generation steps. That is, by changing the mode, the number of set automatic generation steps is changed from one step to a plurality of steps, that is, not only from a single-step change rotation mode to a multi-step change (block rotation) rotation mode,
Changing from multiple steps to multiple steps, ie
For example, from the four-step change mode described above, 8 or 1
It is possible to change to a 6-step change mode or the like. Then, the N-th control state (N = 1) is determined (S10).
4) When the CPU timer 12 counts up (S1)
05), the rotation trigger signal 13 is generated in response to the count-up signal (S106). As described with reference to FIG. 3B, the CPU 11 synchronizes with the rotation trigger signal 13 to set the motor driver driving mode setting register 15.
B, the states of the block rotation speed setting register 15C and the step time setting table 15D are fetched into the motor driver control signal generation circuit 15A, and by this fetching, the rotation mode changes from a single step change to a multiple step change (block rotation) rotation mode. Mode change state becomes effective. Subsequently, the motor driver control signal generation circuit 15A supplied with the rotation trigger signal 13 outputs the motor driver control signal groups 38 and 39 in the first control state (S
107). Then, as long as N is smaller than the set automatic generation step number (S108), it is determined whether the set holding time of the N-th state has elapsed (S109), and if so, the N-th control state Are output (S110), the process returns to S108 as N = N + 1, and the same determination is made. If N is not smaller than the set number of automatic generation steps in S108 (S108), the process returns to S102, and it is determined again whether to change the mode setting.

As described above, the present invention has been described with respect to specific embodiments. However, the present invention is not limited to these embodiments, and is applicable to other embodiments within the scope of the invention described in the claims. You.

For example, in the above embodiment, the CPU built-in timer is used, but an external timer may be used as long as it operates in connection with the CPU.

In the above-described embodiment, the control of the carriage motor for the printer has been described. However, the present invention is of course applicable to the control of other motors for the printer.

In the above-described embodiment, the mode in which one rotation trigger signal is changed by one step at the beginning is adopted, and the mode is changed to four steps. However, ink ejection for printing is performed. In a constant speed state where the rotation speed is high, one rotation trigger signal may be changed by 8 to 16 steps. For example, when adjusting the rotation speed of the CR motor 21 by 2-2 phase excitation,
A mode that changes every eight steps is sufficient. As described above, the present invention is made from the viewpoint that the control of the rotation speed of the CR motor is sufficient if it is adapted as a block of a plurality of steps, for example, in a situation where ink ejection for printing is performed. Therefore, various changes in the number of steps may be used depending on the situation where the rotation speed of the CR motor 21 is adjusted.

Further, in the above-described embodiment, the motor driver control unit 15 is connected to the motor driver control signal generation circuit 1
5A, a motor driver drive mode setting register 15B,
Although the configuration is made up of the block rotation number setting register 15C and the step time setting table 15D at the time of block rotation, in addition to these, for example, an EEPROM is provided in the motor driver control unit 15, and each of the plurality of steps described above is stored in this EEPROM. By writing the motor control signal output state corresponding to each step as a program, the motor control signal state corresponding to each preset step is automatically output sequentially in accordance with the program. You may do it. In this way, by rewriting the EEPROM program, the phase data of the motor driver can be freely rewritten according to the performance of the CPU and the purpose of motor control.

[0067]

As described above, according to the present invention,
To enable at least n (n ≧ 2) motor control signal changes with one rotation trigger signal from the CPU,
The rotation speed of the printer motor can be adjusted with a multiple of the accuracy of the PU timer.

Accordingly, since the ink jetting for printing is performed particularly in the constant speed state where the rotational speed is high, the motor rotation speed during ink jetting, that is, the print head moving speed is determined by a plurality of times of CPU timer accuracy. The adjustment can be performed with double precision, and the printing quality can be improved.

Further, since the number of calls of the CPU for motor control at a high motor rotation speed is reduced to 1 / n, it is possible to increase the time allotted to other data processing by the CPU. The printing speed by the printer can be increased accordingly.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration in which a printer motor control device according to an embodiment of the present invention is applied to control a CR motor of a serial printer.

FIG. 2 is a diagram showing a configuration of a printer motor control device according to an embodiment of the present invention.

FIG. 3 is a timing chart for explaining the operation of the printer motor control device according to the embodiment.

FIG. 4 is a flowchart illustrating a control procedure performed by the control device according to the present embodiment.

FIG. 5 is a diagram for explaining a control method of a conventional printer motor.

FIG. 6 is a diagram for explaining a conventional printer motor control method using a timing chart.

FIG. 7 is a diagram showing a schematic structure of an ink jet nozzle for explaining a problem in a conventional control method of a printer motor.

FIG. 8 illustrates a conventional printer motor control method.
FIG. 4 is a diagram for explaining a problem of color adjustment.

[Explanation of symbols]

Reference Signs List 11 CPU 12 CPU timer 13a to 13f Rotation trigger signal 15 Motor driver control unit 15A Motor driver control signal generation circuit 15B Motor driver drive mode setting register 15C Block rotation speed setting register 15D Step time setting table for block rotation 17 Motor driver Control signal 19 Motor driver 21 Carriage (CR) motor 22 First transmission circuit 23 Clock 25 ROM 27 RAM 33 A-phase current 34 B-phase current 38 A-phase current control signal group 39 B-phase current control signal group 40 Second oscillation Circuit 42 clock

Claims (10)

[Claims] 1. A control device for a printer motor for controlling rotation of a motor by a motor control signal generated by referring to a rotation trigger signal generated in relation to a CPU, wherein the motor is controlled in response to one rotation trigger signal. A controller for a printer motor, comprising means for sequentially changing the control signal by at least n (n is an integer of n ≧ 2) steps. 2. The controller for a printer motor according to claim 1, further comprising: means for setting each step time of the n steps; and changing the motor control signal with respect to the one rotation trigger signal. Means for setting the value of the number n. 3. The controller for a printer motor according to claim 1, further comprising means for changing a value of the number n of steps for changing the motor control signal with respect to the one rotation trigger signal. A controller for a printer motor. 4. The printer motor control device according to claim 1, further comprising means for presetting a motor control state corresponding to each of said n steps. Control device. 5. The printer motor control device according to claim 1, wherein said printer motor is a carriage motor. 6. The printer motor control device according to claim 3, wherein the change of n steps is performed during a constant speed drive of the carriage. 7. The control device for a printer motor according to claim 3, wherein the value of n is changed according to the moving speed of the carriage. 8. A control device for a printer motor according to claim 1, wherein said rotation trigger signal is generated by counting up a timer operating in connection with a CPU. apparatus. 9. The motor rotation is controlled by providing a plurality of modes for changing the motor control signal by n (n is an integer of n ≧ 1) steps in response to one rotation trigger signal generated in relation to the CPU. A controller for a printer motor, comprising: a switching unit for arbitrarily switching the plurality of modes. 10. A printer motor control method for generating a rotation trigger signal in relation to a CPU and generating a motor control signal with reference to the rotation trigger signal to control the rotation of the motor. A method for controlling a motor for a printer, wherein the motor control signal is sequentially changed by at least n (n is an integer of n ≧ 2) steps with respect to the signal.