JP2003019838A - Control of carriage motor in printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique whereby an appropriate control is enabled even when an excess load is applied to a carriage motor of a printer. SOLUTION: A control circuit 200 of the carriage motor 60 has a duty adjustment circuit 220. The duty adjustment circuit 220 prevents a PID output ΣQ from continuously increasing over a predetermined effective limiting value by adjusting an integration result QI at an integrating element 212 when the PID output ΣQ exceeds the effective limiting value. Alternatively, the duty adjustment circuit 220 prevents the PID output ΣQ from continuously increasing over the effective limiting value by adjusting a target velocity Vt when the PID output ΣQ exceeds the effective limiting value continuously by a predetermined number of times.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for controlling the operation of a carriage motor of a printing device.

[0002]

2. Description of the Related Art An ink jet printer includes a carriage having a print head, a carriage motor for moving the carriage, and a drive control device for controlling the carriage motor. FIG. 9 is a block diagram showing the configuration of a conventional drive control device. This drive control device has a control circuit 300, a drive circuit 320, and a carriage motor 330. Carriage motor 3
An encoder 332 for detecting the current velocity Vc of the carriage is provided on the unit 30. Control circuit 300
Is a subtractor 302 for obtaining a deviation ΔV between the target speed Vt and the current speed Vc, a proportional element 304, and an integral element 3
06, a differentiating element 308, and an adder 310. The three calculation elements 304, 306, 308 output calculation results according to the speed deviation ΔV, and these calculation results are added by the adder 310. This addition result ΣQ
Are supplied to the drive circuit 320 as control signals. The drive circuit 320 receives the drive signal Sdr corresponding to the control signal ΣQ.
Is supplied to the carriage motor 330 to drive it.

FIG. 10 is an explanatory diagram showing the relationship between the motor drive signal Sdr and the characteristics of the carriage motor 330.
FIG. 10A shows a signal change of the motor drive signal Sdr. The duty Dt of the motor drive signal Sdr is a value obtained by dividing the on-level period Ton by one cycle Tp of the drive signal. In the present specification, the motor drive signal Sdr
Duty Dt of "carriage motor duty"
Also called.

When a brush DC motor is used as the carriage motor 330, its torque / rotational speed characteristic is proportional to the duty Dt, as shown in FIG. 10 (B). The drive circuit 320 generates the drive signal Sdr so that the duty Dt of the drive signal Sdr is proportional to the control signal ΣQ. As a result, the carriage motor 330 generates a driving force according to the control signal ΣQ given from the control circuit 300 to drive the carriage.

[0005]

The control circuit 30 described above is provided.
A control circuit that performs normal PID control such as 0 can control the speed and position of the carriage motor 330 with high accuracy. However, if the load on the carriage motor 330 becomes excessive for some reason, the control accuracy may decrease. For example, when the frictional force of the guide rails of the carriage becomes large or when the carriage has an excessive weight, the carriage motor 330 is overloaded.

FIG. 11 is a graph showing the state of control when an excessive load is applied to the carriage motor 330. In FIG. 11A, the horizontal axis represents position (or time) and the vertical axis represents speed. The target speed Vt is the carriage j
It is set in advance according to the deviation between the target position Pt and the current position. When the carriage motor 330 is overloaded, the current speed Vc reaches the target speed Vt even if the level of the control signal ΣQ reaches a value corresponding to 100% duty of the carriage motor, as shown in FIG. 11 (B). It may not reach. At this time, the level of the control signal ΣQ continues to increase. The reason for this is that the speed deviation ΔV is kept positive, and the integration results in the integrating element 306 gradually accumulate.

In this state, the current position is the target position Pt
As the target speed Vt decreases, the current speed Vt
It will be below c. As a result, the speed deviation ΔV becomes negative and the value of the control signal ΣQ also begins to decrease. However,
In the case of 1 (B), the level of the control signal ΣQ is 100
Since it can be said that the value corresponding to the% duty is far exceeded, the duty of the carriage motor is 10 for a while.
It is maintained at 0%. After that, the target speed Vt is considerably reduced, and the carriage starts decelerating for the first time after the control signal ΣQ falls below the value corresponding to 100% duty.
As a result, even when the carriage reaches the target position Pt, the carriage motor 330 continues to operate and stops only when the target position Pt is exceeded, as indicated by the arrow.

As described above, conventionally, there has been a problem that, when an excessive load is applied to the carriage motor, appropriate control may not be performed.

The present invention has been made to solve the above-mentioned conventional problems, and provides a technique capable of performing appropriate control even when an excessive load is applied to a carriage motor of a printing apparatus. The purpose is to do.

[0010]

In order to achieve the above object, the first printing device of the present invention comprises:
A printing apparatus having a print head includes a carriage on which the print head is mounted, a carriage motor for moving the carriage, and a drive control device for controlling the operation of the carriage motor. The drive control device includes a drive circuit that drives the carriage motor, a detection unit that detects a current speed of the carriage, and a target speed generation unit that generates a target speed of the carriage.
And a control unit for generating a control signal to be supplied to the drive circuit according to a deviation between the target speed of the carriage and the current speed. Further, the control unit includes a plurality of calculation elements each including a proportional element and an integral element, each calculating a calculation result according to the speed deviation, an adder for adding the calculation results of the plurality of calculation elements, and the addition. An adjusting unit that adjusts the signal level of the control signal according to the addition result of the converter. The adjustment unit prevents the addition result from continuing to increase beyond the effective limit value by adjusting the integration result in the integrating element when the addition result exceeds a predetermined effective limit value.

In the first printing apparatus, when the addition result exceeds the predetermined effective limit value, the integration result in the integrating element is adjusted to prevent the addition result from continuously increasing beyond the effective limit value. Therefore, even when an excessive load is applied to the carriage motor of the printing apparatus, if the speed deviation decreases, appropriate drive control can be immediately performed in response to this.

In addition, the integral element is the velocity deviation ΔV.
And the integration gain Ki, the product ΔV · Ki is updated by adding the previous integration result to the product ΔV · Ki, and the adjusting unit updates the product ΔV · Ki when the addition result exceeds a predetermined effective limit value. The integration result may be adjusted by setting the value of Ki to 0.

Alternatively, the adjusting unit subtracts the difference between the addition result and the effective limit value from the integration result in the integrating element when the addition result exceeds a predetermined effective limit value, and the addition result is added. May be adjusted to a value equal to the effective limit value to adjust the integration result.

According to these configurations, it is possible to easily prevent the addition result from continuing to increase beyond the effective limit value.

The effective limit value is preferably a value corresponding to the maximum output of the carriage motor.

According to this structure, it is possible to perform appropriate control while fully utilizing the capabilities of the carriage motor.

In the second printing apparatus according to the present invention, the adjusting section adjusts the target speed in the target speed generating section when the addition result exceeds the predetermined effective limit value continuously for the predetermined number of times. This prevents the addition result from continuing to increase beyond the valid limit value.

In the second printing apparatus, the target speed in the target speed generating unit is adjusted to prevent the addition result from continuing to increase beyond the effective limit value. Therefore, the carriage motor of the printing apparatus is excessively large. Even when a load is applied, if the speed deviation is reduced, appropriate drive control can be immediately performed accordingly.

The adjusting unit sets the target speed in the target speed generating unit to a value equal to the current speed when the addition result exceeds the predetermined effective limit value a predetermined number of times in succession. May be.

With this configuration, it is possible to easily prevent the addition result from continuing to increase beyond the effective limit value.

The present invention can be implemented in various forms. For example, a motor drive control method and device, a print control method and print control device, a printing method and printing device, and those methods or devices. It can be realized in the form of a computer program for realizing the function of, a recording medium recording the computer program, a data signal embodied in a carrier wave including the computer program, and the like.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described in the following order based on examples. A. Overall configuration of device: B. First Example: C.I. Second embodiment: D. Third Example: E. Modification:

A. Overall Configuration of Apparatus: FIG. 1 is a schematic perspective view showing the main configuration of an inkjet printer 20 as an embodiment of the present invention. The printer 20 includes a paper feed motor 30 that feeds a print paper P in the sub-scanning direction SS, a platen 40, and a carriage 5 on which a print head 52 is mounted.
0 and a carriage motor 60 that moves the carriage 50 in the main scanning direction MS.

The carriage 50 includes a carriage motor 60.
It is pulled by a pulling belt 62 driven by and is moved along a guide rail 64. In addition to the print head 52, a black cartridge 54 and a color ink cartridge 56 are mounted on the carriage 50.

Home position of the carriage 50 (see FIG.
At a position on the right side of), a capping device 80 for sealing the nozzle surface of the print head 52 when stopped is provided. When the carriage 50 reaches the top of the capping device 80 after the print job is completed, the capping device 80 is automatically raised by a mechanism (not shown) to seal the nozzle surface of the print head 52. This capping prevents the ink in the nozzle from drying. Positioning control of the carriage 50 is performed, for example, in order to accurately position the carriage 50 at the position of the capping device 80.

FIG. 2 is a block diagram showing the electrical configuration of the printer 20. The printer 20 includes the main control circuit 10
2, CPU 104, main control circuit 102 and CPU
Various memories (ROMs connected to the 104 via a bus)
110, RAM 112, EEPROM 114). The main control circuit 102 includes an interface circuit 120 that transmits and receives signals to and from an external device such as a personal computer, and a paper feed motor drive circuit 130.
Head drive circuit 140 and CR motor drive circuit 15
0 and 0 are connected.

The paper feed motor 30 is driven by the paper feed motor drive circuit 130 to rotate the paper feed roller 34, thereby moving the printing paper P in the sub-scanning direction. The paper feed motor 30 is provided with a rotary encoder 32, and an output signal of the rotary encoder 32 is input to the main control circuit 102.

A print head 52 having a plurality of nozzles (not shown) is provided on the bottom surface of the carriage 50. Each nozzle is driven by the head drive circuit 140 to eject an ink droplet.

The carriage motor 60 is driven by the CR motor drive circuit 150. This printer 20
A linear encoder 70 for detecting the position and speed of the carriage 50 along the main scanning direction is provided. The linear encoder 70 is composed of a linear code plate 72 provided in parallel with the main scanning direction and a photo sensor 74 provided in the carriage 50. The output signal of the linear encoder 70 is input to the main control circuit 102.

The main control circuit 102 has a function of supplying control signals to the three drive circuits 130, 140, 150, respectively, and the interface circuit 12 has a function.
It also has a function of decoding various print commands received at 0, controlling print data adjustment, and monitoring various sensors. On the other hand, the CPU 104 has various functions for assisting the main control circuit 102, and executes various memory controls, for example.

FIG. 3 is a block diagram showing the configuration of a drive control device for the carriage motor 60. This drive control device includes a CR motor control circuit 200 and a CR motor drive circuit 150. The CR motor control circuit 20
0 is a part of the main control circuit 102 shown in FIG.

The output signal Sen of the linear encoder 70 is
It is input to the position calculation circuit 230 and the speed calculation circuit 232 in the CR motor control circuit 200. These circuits 23
0 and 232 use the A-phase signal and B-phase signal (not shown) of the output signal Sen of the encoder 70 to determine the current position Pc and the current velocity Vc of the carriage, respectively. The first subtractor 202 receives the given target position Pt and the current position Pc.
The deviation ΔP between the above and is obtained and input to the target speed generation circuit 204. The target speed generation circuit 204 generates a target speed Vt according to this position deviation ΔP. The change pattern of the target speed Vt is the same as that shown by the solid line in FIG. 11, for example.

The second subtractor 206 receives the target speed Vt.
The deviation ΔV between the current speed Vc and the current speed Vc is calculated.
Is input to the proportional element 210, the integral element 212, and the derivative element 214. These three calculation elements 210, 212,
The calculation results QP, QI, and QD of 214 are added by the adder 216, and the addition result ΣQ is calculated.

The outputs QP, QI, QD of the respective arithmetic elements 210, 212, 214 and the addition result ΣQ thereof are given, for example, by the following equations (1) to (4). QP (j) = ΔV (j) × Kp (1) QI (j) = QI (j−1) + ΔV (j) × Ki (2) QD (j) = {ΔV (j) −ΔV (j −1)} × Kd (3) ΣQ (j) = QP (j) + QI (j) + QD (j) (4) where j is time, Kp is proportional gain, Ki is integral gain, Kd is a differential gain.

The duty adjusting circuit 220 adjusts the integrating element 212 or the target speed generating circuit 204 according to the addition result ΣQ (also referred to as “PID output”) to supply the Didy signal Dt to the drive circuit 150.
Adjust the level of. The duty signal Dt is a signal proportional to the addition result ΣQ, and the carriage motor 60
Is a signal indicating the duty of. Duty adjustment circuit 2
The processing contents of 20 will be described later.

The CR motor drive circuit 150 is a DC-DC converter 154 composed of a transistor bridge.
And a base drive circuit 152. The base drive circuit 152 generates a base signal to be applied to the base of the transistor of the DC-DC converter 154 according to the duty signal Dt supplied from the CR motor control circuit 200. The DC-DC converter 154 generates a motor drive signal Sdr according to this base signal and supplies it to the carriage motor 60. The relationship between the motor drive signal Sdr and the characteristics of the carriage motor is the same as that shown in FIG.

B. 1st Example: FIG. 4 has shown operation | movement of the CR motor control circuit in a comparative example. In this comparative example, the CR motor control circuit 200 shown in FIG. 3 from which the duty adjustment circuit 220 is omitted is used. In other words, it is assumed in the comparative example that the normal PID control is performed without using the duty adjustment circuit 220.

In the table of FIG. 4, time j, target speed Vt, current speed Vc, speed deviation ΔV, proportional output (P
Output) QP, integral output (I output) QI, and PI output ΣQ (= QP + QI) are shown. As indicated in the remarks, the proportional gain Kp is assumed to be 1.5 and the integral gain Ki is assumed to be 1. The differential output is omitted (that is, the differential gain is set to 0). The setting values of these gains are merely values for convenience of description.

At time j = 0, I output QI is assumed to be 700. From time j = 1 to time j = 6,
The target speed Vt is constant at 200 cps (characters / second), and the current speed Vc gradually increases from 80 cps to 180 cps. During this time, since the speed deviation ΔV is positive, the I output QI also gradually increases.

As shown in the lower part of FIG. 4, PI output ΣQ =
1000 corresponds to 100% duty, and when the PI output ΣQ is 1000 or more, the duty of the carriage motor 50 is set to 100%. Therefore, in the following, this value 1000 is referred to as "the effective limit value Σ of the PI output ΣQ.
Qmax ".

The PI output ΣQ exceeds the effective limit value ΣQmax after the time j = 2, but since the speed deviation ΔV is kept positive, both the integrated output QI and the PI output ΣQ continue to increase. During the period from time j = 6 to time j = 9, the current speed Vc and the target speed Vt are both kept constant, but the current speed Vc has not reached the target speed Vt. The reason for this is that the carriage motor 60 is operating at the maximum output (that is, 100% duty) during this period, but since the load is larger than the maximum output, the current speed Vc does not increase and is kept substantially constant. Because it will be. As a result, since the speed deviation ΔV is kept positive,
Both the integrated output QI and the PI output ΣQ continue to increase.

At time j = 11, the current position approaches the target position Pt (FIG. 11), so the target speed Vt starts to decrease. However, during that period, PI output Σ
Since Q greatly exceeds the effective limit value ΣQmax, even if the target speed Vt decreases, the PI output ΣQ still has the effective limit value ΣQ.
It takes time to go below max. Actually, the duty of the drive signal of the carriage motor 60 becomes 100% or less only when the PI output ΣQ becomes the effective limit value ΣQmax or less, and then the deceleration of the motor is started.

As described above, the simple PI control (or P
In ID control), if the addition result ΣQ of the outputs of the calculation elements continues to increase beyond the effective limit value ΣQmax corresponding to the maximum output of the motor, even if the target speed Vt starts to decrease, the current speed Vc decreases It will take a considerable amount of time. As a result, as described in FIG. 11 described above,
It becomes difficult for the carriage to stop at the target position Pt.

FIG. 5 shows a CR in the first embodiment of the present invention.
The operation of the motor control circuit 200 is shown. In the first embodiment, the duty adjusting circuit 220 forcibly sets the product ΔV · Ki in the integrating element 212 to zero when the PI output ΣQ exceeds the effective limit value ΣQmax = 1000. For example, at time j = 2, ΣQ = 1070, which exceeds the effective limit value ΣQmax. Therefore, the product ΔV · Ki is 0
And the I output QI is reset to 820 and the PI output ΣQ is recalculated to 970. In addition,
In FIG. 5, the arrow from the top to the bottom indicates that the adjustment by the duty adjustment circuit 220 is performed. The arrow to the upper right indicates that the adjusted integration result QI is used for the next integration calculation.

At time j = 3, the I output QI is updated based on the I output QI = 820 at the previous time j = 2, but the PI output ΣQ becomes 1020, and the effective limit value ΣQma
x exceeds 1000. Therefore, even at time j = 3, the product ΔV · Ki is set to 0, the I output QI is reset to 820 accordingly, and the PI output ΣQ
Is recalculated to 940.

From time j = 4 to time j = 7 thereafter, since the PI output ΣQ does not exceed the effective limit value ΣQmax, the duty adjustment circuit 220 does not perform the adjustment. From time j = 8 to time j = 10, the PI output ΣQ again exceeds the effective limit value ΣQmax, so the product ΔV · Ki is adjusted by the duty adjustment circuit 220, and the I output QI and the PI output ΣQ are also reset. Is set.

When the target speed Vt starts to decrease from time j = 11 and the speed deviation ΔV becomes negative, P is correspondingly increased.
The I output ΣQ also drops rapidly. Therefore, in the first embodiment, the current speed Vc starts to decrease earlier than in the comparative example shown in FIG. Specifically, in the comparative example of FIG. 4, the PI output ΣQ exceeds the effective limit value ΣQmax even at times j = 11, 12, so the duty of the drive signal of the carriage motor 60 is maintained at 100%. As a result, the current speed Vc is kept the same.
On the other hand, in the first embodiment of FIG. 5, time j = 11,
Since the PI output ΣQ is less than the effective limit value ΣQmax in 12, the duty of the drive signal of the carriage motor 60 is also less than 100%, and as a result, the current speed Vc starts to decrease from time j = 12. .

FIG. 6 shows the operations of the comparative example and the first embodiment in comparison. However, the graph of FIG. 6 does not completely correspond to the changes in the tables of FIGS. 4 and 5, but merely shows the tendency of those changes.

As shown in FIG. 6A, during the period in which the target speed Vt is maintained constant, the change in the current speed Vc is not so different between the comparative example and the first embodiment. The reason for this is that, as shown in FIG. 6B, in this period, the PI output ΣQ becomes equal to or more than the effective limit value ΣQmax in the comparative example, and therefore the duty of the carriage motor 60 is 100%. In the example as well, the PI output ΣQ is almost close to the effective limit value ΣQmax, so that the duty of the carriage motor 60 is almost 100%.

When the target speed Vt starts to decrease, the PI output ΣQ rapidly decreases in the first embodiment.
c also immediately drops, and the carriage 50 stops at approximately the target position Pt. On the other hand, in the comparative example, the PI output ΣQ remains effective limit value Σ for a while even if the target speed Vt decreases.
Since it is above Qmax, the decrease in speed will be delayed. As a result, the carriage 50 stops at a position beyond the target position Pt, as shown by the arrow.

As described above, in the first embodiment, the PI output Σ
When Q exceeds a predetermined effective limit value ΣQmax, the product ΔV · K i in the integral element 212 is forcibly set to zero, so that the PI output ΣQ can be set to the effective limit value ΣQmax or less. As a result, even if the speed deviation ΔV remains positive, the deviation ΔV is prevented from being excessively accumulated in the I output QI. Therefore, the target speed V
When t starts to decrease, it is possible to control the operation of the carriage motor 60 so that the current speed Vc decreases correspondingly. Further, it is possible to stop the carriage 50 at approximately the target position Pt.

C. Second Embodiment: FIG. 7 shows the operation of the CR motor control circuit 200 in the second embodiment of the present invention. In the second embodiment, the duty adjustment circuit 220 is
When the PI output ΣQ exceeds the effective limit value ΣQmax, P
Difference between I output ΣQ and effective limit value ΣQmax (ΣQ-ΣQma
x) is subtracted from the I output QI to set the PI output ΣQ to a value equal to the effective limit value ΣQmax. For example, time j =
2, the PI output ΣQ before adjustment is 1070, which exceeds the effective limit value ΣQmax, so the difference (ΣQ−Σ
Qmax) = 70 is subtracted from the I output QI. As a result, the PI output ΣQ is forcibly set to a value equal to ΣQmax = 1000.

At time j = 3, the I output QI is updated based on the I output QI = 850 at the previous time j = 2, but the PI output ΣQ becomes 1050, and the effective limit value ΣQma
x exceeds 1000. Therefore, even at time j = 3, the difference (ΣQ−ΣQmax) = 50 is subtracted from the I output QI, and the PI output ΣQ is forcibly ΣQmax = 1000.
Is set to a value equal to. Since the processing after time j = 4 is the same, the description is omitted.

As described above, in the second embodiment, the PI output Σ
When Q exceeds a predetermined effective limit value ΣQmax, the difference (ΣQ-ΣQmax) is subtracted from the I output QI to obtain PI
Since the output ΣQ is set to a value equal to the effective limit value ΣQmax, the PI output ΣQ can be kept below the effective limit value ΣQmax. As a result, even if the state where the speed deviation ΔV is positive continues, it is possible to prevent the deviation ΔV from being excessively accumulated in the I output QI. Therefore, as in the first embodiment described above, when the target speed Vt starts to decrease, it is possible to control the operation of the carriage motor 60 so that the current speed Vc immediately decreases accordingly. Also,
It is possible to stop the carriage 50 at approximately the target position Pt.

In the first and second embodiments, the duty adjusting circuit 220 determines that the PI output ΣQ is the effective limit value ΣQma.
By adjusting the integration result (ie, I output QI) in the integration element 212 when x is exceeded, PI
It is common in that the output ΣQ is prevented from continuing to increase beyond the effective limit value ΣQmax.

D. Third Embodiment: FIG. 8 shows the operation of the CR motor control circuit 200 in the third embodiment of the present invention. In the third embodiment, the duty adjustment circuit 220 is
When the PI output ΣQ exceeds the effective limit value ΣQmax N times, the target speed Vt in the target speed generation circuit 204 is reset to the value of the current speed Vc at that time. Here, the number of times N
Can be set to an arbitrary value of 1 or more, but in the example of FIG. 8, N = 4.

In the example of FIG. 8, time j = 2 to time j = 5
PI output ΣQ is effective limit value ΣQmax
Therefore, the target speed Vt from the subsequent time j = 6 is reset to the current speed Vc = 180 cps at that time. The value of this target speed Vt is
When the value of the target speed Vt before the change changes (time j = 1
It is maintained until 1).

The PI output ΣQ exceeds the effective limit value ΣQmax = 1000 in the third embodiment, but the speed deviation ΔV
Becomes 0, the speed deviation ΔV is not accumulated in the I output QI. Therefore, compared to the comparative example, the I output QI and the PI output ΣQ can be suppressed to be small. Therefore, when the target speed Vt starts to decrease, the current speed Vc immediately decreases accordingly, so that the carriage motor 60 decreases.
It is possible to control the operation of. Further, it is possible to stop the carriage 50 at approximately the target position Pt.

E. Modifications: The present invention is not limited to the above-described embodiments and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are also possible. is there.

E1. Modification 1: As the carriage motor 60, a DC motor or an AC other than the brushed DC motor is used.
It is also possible to use a motor. The present invention can also be applied to control of motors other than the carriage motor of the printer.

E2. Modified Example 2: In the above embodiment, a part of the configuration realized by hardware may be replaced with software, and conversely, a part of the configuration realized by software may be replaced with hardware. May be. For example, the control circuit 20
It is also possible to realize some or all of the functions of 0 (FIG. 3) by a computer program.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing the main configuration of an inkjet printer 20 as an embodiment of the present invention.

FIG. 2 is a block diagram showing an electrical configuration of the printer 20.

FIG. 3 is a block diagram showing a configuration of a drive control device of a carriage motor 60.

FIG. 4 is an explanatory diagram showing an operation of a CR motor control circuit in a comparative example.

FIG. 5 is a CR motor control circuit 200 according to the first embodiment.
Explanatory diagram showing the operation of FIG.

FIG. 6 is a graph showing the operations of the comparative example and the first embodiment in comparison.

FIG. 7 is a CR motor control circuit 200 according to the second embodiment.
Explanatory diagram showing the operation of FIG.

FIG. 8 is a CR motor control circuit 200 according to the third embodiment.
Explanatory diagram showing the operation of FIG.

FIG. 9 is a block diagram showing a configuration of a conventional drive control device.

FIG. 10: Motor drive signal Sdr and carriage motor 3
Explanatory drawing which shows the relationship with the characteristic of 30.

FIG. 11 is a graph showing how control is performed when an excessive load is applied to the carriage motor.

[Explanation of symbols]

20 ... Inkjet printer 30 ... Paper feed motor 32 ... Rotary encoder 34 ... Paper feed roller 40 ... Platen 50 ... Carriage 52 ... Print head 54 ... Black cartridge 56 ... Color ink cartridge 60 ... Carriage motor 62 ... traction belt 64 ... Guide rail 70 ... Linear encoder 72 ... Code plate 74 ... Photo sensor 80 ... Capping device 102 ... Main control circuit 104 ... CPU 110 ... ROM 112 ... RAM 114 ... EEPROM 120 ... Interface circuit 130 ... Paper feed motor drive circuit 140 ... Head drive circuit 150 ... CR motor drive circuit 152 ... Base drive circuit 154 ... DC-DC converter 200 ... CR motor control circuit 202 ... First subtractor 204 ... Target speed generation circuit 206 ... Second subtractor 210 ... Proportional element 212 ... Integral element 214 ... Differential element 216 ... Adder 220 ... Duty adjusting circuit 230 ... Position calculation circuit 232 ... Speed calculation circuit 300 ... Control circuit 302 ... Subtractor 304 ... Proportional element 306 ... Integral element 308 ... differential element 310 ... Adder 320 ... Driving circuit 330 ... Carriage motor 332 ... Encoder

Claims (10)

[Claims] 1. A printing apparatus having a print head, comprising: a carriage on which the print head is mounted; a carriage motor for moving the carriage; and a drive control device for controlling the operation of the carriage motor. The drive control device includes a drive circuit that drives the carriage motor, a detection unit that detects a current speed of the carriage, a target speed generation unit that generates a target speed of the carriage, a target speed of the carriage, and a current speed of the carriage. A control unit for generating a control signal to be supplied to the drive circuit according to a deviation from the speed, the control unit including a proportional element and an integral element, and calculating according to the speed deviation. A plurality of calculation elements for respectively obtaining results, an adder for adding the calculation results of the plurality of calculation elements, and the control unit according to the addition result of the adder. An adjusting unit that adjusts the signal level of the control signal, wherein the adjusting unit adjusts the integration result in the integrating element when the addition result exceeds a predetermined effective limit value, whereby the addition result is A printing apparatus, characterized in that it is prevented from continuing to increase beyond the effective limit value. 2. The printing apparatus according to claim 1, wherein the integration element updates the integration result by adding a previous integration result to a product ΔV · Ki of the speed deviation ΔV and an integration gain Ki. The adjusting device adjusts the integration result by setting the value of the product ΔV · Ki to 0 when the addition result exceeds a predetermined effective limit value. 3. The printing apparatus according to claim 1, wherein the adjusting unit calculates the difference between the addition result and the effective limit value when the addition result exceeds a predetermined effective limit value. A printing apparatus that adjusts the integration result by subtracting it from the integration result in step 1 and setting the addition result to a value equal to the effective limit value. 4. The printing device according to claim 1, wherein the effective limit value is a value corresponding to a maximum output of the carriage motor. 5. A printing apparatus having a print head, comprising: a carriage on which the print head is mounted; a carriage motor for moving the carriage; and a drive control device for controlling the operation of the carriage motor. The drive control device includes a drive circuit that drives the carriage motor, a detection unit that detects a current speed of the carriage, a target speed generation unit that generates a target speed of the carriage, a target speed of the carriage, and a current speed of the carriage. A control unit that generates a control signal to be supplied to the drive circuit according to a deviation from the speed, and the control unit includes a proportional element and an integral element, and calculates according to the speed deviation. A plurality of calculation elements for respectively obtaining results, an adder for adding the calculation results of the plurality of calculation elements, and An adjusting unit that adjusts the signal level of the control signal, wherein the adjusting unit adjusts the target speed in the target speed generating unit when the addition result exceeds the predetermined effective limit value for a predetermined number of times in succession. By so doing, it is possible to prevent the addition result from continuing to increase beyond the effective limit value. 6. The printing apparatus according to claim 5, wherein the adjustment unit sets a target speed in the target speed generation unit when the addition result exceeds a predetermined effective limit value for a predetermined number of times in succession. A printing device that sets a value equal to the current speed. 7. A drive control device for controlling the operation of the carriage motor, the drive control device being used in a printing device having a carriage on which a print head is mounted and a carriage motor for moving the carriage. A drive circuit that drives the carriage, a detection unit that detects the current speed of the carriage, a target speed generation unit that generates a target speed of the carriage, and the drive circuit according to a deviation between the target speed of the carriage and the current speed. And a control unit for generating a control signal to be supplied to the control unit, wherein the control unit includes a proportional element and an integral element, and a plurality of calculation elements for respectively calculating a calculation result according to the velocity deviation, An adder that adds the calculation results of the calculation elements, and an adjusting unit that adjusts the signal level of the control signal according to the addition result of the adder are included. The adjustment unit prevents the addition result from continuously increasing beyond the effective limit value by adjusting the integration result in the integration element when the addition result exceeds a predetermined effective limit value. A drive control device characterized by the above. 8. A drive control device for controlling the operation of the carriage motor, the drive control device being used in a printing device having a carriage on which a print head is mounted and a carriage motor for moving the carriage. A drive circuit that drives the carriage, a detection unit that detects the current speed of the carriage, a target speed generation unit that generates a target speed of the carriage, and the drive circuit according to a deviation between the target speed of the carriage and the current speed. And a control unit for generating a control signal to be supplied to the control unit, wherein the control unit includes a proportional element and an integral element, and a plurality of calculation elements for respectively calculating a calculation result according to the velocity deviation, An adder that adds the calculation results of the calculation elements, and an adjusting unit that adjusts the signal level of the control signal according to the addition result of the adder are included. The adjusting unit adjusts the target speed in the target speed generating unit when the addition result exceeds a predetermined effective limit value for a predetermined number of times in succession so that the addition result exceeds the effective limit value. The drive control device is characterized in that it is prevented from continuing to increase. 9. A method for controlling an operation of a carriage motor for moving a carriage having a print head, comprising: (a) detecting a current speed of the carriage; and (b) generating a target speed of the carriage. And (c) generating a control signal to be supplied to the drive circuit of the carriage motor according to the deviation between the target speed of the carriage and the current speed, and the step (c) includes d) using a plurality of calculation elements including a proportional element and an integral element to obtain a plurality of calculation results according to the speed deviation; (e) adding the plurality of calculation elements; Adjusting the signal level of the control signal according to the addition result of the adder, and the step (f) includes integrating the integration element when the addition result exceeds a predetermined effective limit value. By adjusting the result, the control method of a carriage motor, characterized by preventing the addition result continues to increase beyond the effective limits. 10. A method for controlling the operation of a carriage motor for moving a carriage having a print head, comprising: (a) detecting a current speed of the carriage; and (b) generating a target speed of the carriage. And (c) generating a control signal to be supplied to the drive circuit of the carriage motor according to the deviation between the target speed of the carriage and the current speed, and the step (c) includes d) using a plurality of calculation elements including a proportional element and an integral element to obtain a plurality of calculation results according to the speed deviation; (e) adding the plurality of calculation elements; Adjusting the signal level of the control signal according to the addition result of the adder, the step (f), when the addition result exceeds a predetermined effective limit value a predetermined number of times consecutively, The eye By adjusting the speed, control method of a carriage motor, characterized by preventing the addition result continues to increase beyond the effective limits.