US20030025471A1 - Control unit and method for controlling motor for use in printer, and storage medium storing control program - Google Patents
Control unit and method for controlling motor for use in printer, and storage medium storing control program Download PDFInfo
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- US20030025471A1 US20030025471A1 US10/253,498 US25349802A US2003025471A1 US 20030025471 A1 US20030025471 A1 US 20030025471A1 US 25349802 A US25349802 A US 25349802A US 2003025471 A1 US2003025471 A1 US 2003025471A1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J19/00—Character- or line-spacing mechanisms
- B41J19/18—Character-spacing or back-spacing mechanisms; Carriage return or release devices therefor
- B41J19/20—Positive-feed character-spacing mechanisms
- B41J19/202—Drive control means for carriage movement
Definitions
- the DC unit 6 comprises a position calculating part 6 a , a subtracter- 6 b , a target speed calculating part 6 c , a speed calculating part 6 d , a subtracter 6 e , a proportional element 6 f , an integrating element 6 g , a differentiating element 6 h , an adder 6 i , a D/A converter 6 j , a timer 6 k , and an acceleration control part 6 m.
- the subtracter 6 e is designed to calculate a speed deviation of the actual speed of the carriage 3 , which is calculated by the speed calculating part 6 d , from a target speed.
- the driver 5 has, e.g., four transistors. By turning each of the transistors ON and OFF on the basis of the output of the D/A converter 6 j , the driver 5 can be selectively in (a) an operation mode in which the CR motor 4 is normally or reversely rotated, (b) a regenerative brake operation mode (a short brake operation mode, i.e., a mode in which the stopping of the CR motor is maintained), or (c) a mode in which the CR motor is intended to be stopped.
- a regenerative brake operation mode a short brake operation mode, i.e., a mode in which the stopping of the CR motor is maintained
- a mode in which the CR motor is intended to be stopped.
- control unit in this second preferred embodiment can suppress the fluctuation in speed of the CR motor 4 , and can also suppress the fluctuation in speed due to other factors.
- the computer body 131 comprises an internal memory 135 of a RAM, and a built-in or exterior memory unit 136 .
- a flexible or floppy disk (FD) drive 137 As the memory unit 136 , a flexible or floppy disk (FD) drive 137 , a CD-ROM drive 138 and a hard disk drive (HD) unit 139 are mounted.
- a flexible disk or floppy disk (FD) 141 which is inserted into a slot of the FD drive 137 to be used, a CD-ROM 142 which is used for the CD-ROM drive 138 , or the like is used as a storage medium 140 for use in the memory unit 136 .
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- Character Spaces And Line Spaces In Printers (AREA)
- Control Of Electric Motors In General (AREA)
- Control Of Direct Current Motors (AREA)
- Ink Jet (AREA)
- Accessory Devices And Overall Control Thereof (AREA)
Abstract
There is provided a control unit capable of suppressing the fluctuation in speed a motor for use in a printer. The control unit comprises: a speed detecting part for detecting the speed of a motor for use in a printer in a predetermined period tv; an average speed calculating part for calculating an average speed using at least the current detected speed, which is detected by the speed detecting part, and a detected speed which has been detected n (≧2), which corresponds to substantially half period of the fluctuation in speed of the motor, before the timing in detecting the current detected speed; and a speed control part for controlling the speed of the motor on the basis of a speed deviation of the average speed, which is the output of the average speed calculating part, from a target speed of the motor.
Description
- 1. Field of the Invention
- The present invention relates generally to a control unit and method for controlling a motor for use in a printer, and a storage medium storing a control program. More specifically, the invention is used for controlling the speed of a motor for driving a carriage of a serial printer.
- 2. Description of Related Art
- In a typical serial printer such as an ink jet printer, a recording head scans on a printing paper to print. This recording head is fixed to a carriage to move with the carriage. This carriage is driven by a DC (Direct Current) motor. The system for driving the carriage is as follows.
- First, a timing belt is stretched at a predetermined tension between a driving pulley, which is fixed to the rotating shaft of the DC motor, and a driven wheel which is a companion to the driving pulley. The carriage is mounted on the timing belt. Thus, the carriage is driven by the rotation of the DC motor so as to move main scanning directions.
- When the carriage is moving at a constant speed, i.e., when the DC motor is rotating at a constant speed, print is carried out.
- Conventionally, the speed control for causing the speed of the DC motor to be a constant speed is carried out by a PID control based on the deviation of a detected actual speed from a target speed.
- However, as shown in FIG. 13, a typical DC motor has a
stator 210 and arotor 220. Thestator 210 comprises ayoke 210 a and amagnetic pole 210 b. Therotor 220 comprises aprotruding portion 220 a which serves as a magnetic pole of an electromagnet, and acoil 220 b which is wound onto the base portion of theprotruding portion 220 a. Therotor 220 is designed to sequentially switch the polarity of the electromagnet by the operation of acommutator 230 and abrush 240. Therefore, the DC motor has the fluctuation in torque. Assuming that the number of phases of the DC motor (the number of coils, i.e., the number of the base portions of theprotruding portions 220 a) is p, the fluctuation in torque occurs 2p times while the DC motor makes one rotation. Furthermore, the number of phases of the DC motor is 3 in FIG. 13. - Therefore, in the serial printer using the DC motor for driving the carriage, there is a problem in that the speed of the carriage (i.e., the speed of the DC motor) fluctuates due to the fluctuation in torque of the DC motor to cause the dispersion between printed dots, so that it is not possible to carry out a precise print.
- It is therefore an object of the present invention to eliminate the aforementioned problems and to provide a control unit and method for controlling a motor for use in a printer, which can suppress the fluctuation in speed of the motor, and a storage medium having a control program recorded therein for controlling a motor for use in a printer.
- In order to accomplish the aforementioned and other objects, according to one aspect of the present invention, there is provided a control unit for controlling a motor for use in a printer, the control unit comprising: a speed detecting part for detecting the speed of a motor for use in a printer in a predetermined period tv; an average speed calculating part for calculating an average speed using at least the current detected speed, which is detected by the speed detecting part, and a detected speed which has been detected n (≧2), which corresponds to substantially half period of the fluctuation in speed of the motor, before the timing in detecting the current detected speed; and a speed control part for controlling the speed of the motor on the basis of a speed deviation of the average speed, which is the output of the average speed calculating part, from a target speed of the motor.
- Furthermore, assuming that the period of the fluctuation in speed of the motor is Tv, the number n used for calculating the average speed preferably meets the following expression.
- T v/(2t v)−2≦n<T v/(2t v)+2
- The average speed calculating part preferably calculates an average speed of k+1 detected speeds from the current detected speed to a detected speed of k (n>k≧0) before, and k+1 detected speeds from a detected speed of n before to a detected speed of k+1 before.
- The speed control part preferably has a differentiating element which operates on the basis of the speed deviation of the average speed from the target speed.
- The speed control part may have a proportional element which operates on the basis of the speed deviation of the average speed from the target speed.
- The speed detecting part may comprise an encoder for generating an output pulse in accordance with the rotation of the motor, and a speed calculating part for calculating the speed of the motor in a period of the output pulse on the basis of the output pulse of the encoder.
- The motor may be a carriage motor for use in an ink jet printer, and the encoder may generate the output pulse in accordance with the movement of a carriage driven by the carriage motor via a pulley, which is mounted of the rotating shaft of the carriage motor, and via a timing belt which is driven by the pulley.
- Preferably, assuming that the distance between adjacent slits of a code plate of the encoder is λ, that a pitch circle length of the pulley is L and that the number of phases of the motor is p, the n meets the following expression.
- L/(4pλ)≦n<L/(4pλ)+2
- The speed control part may further comprise: a second speed calculating part for calculating the speed of the motor in a second predetermined period on the basis of the output pulse of the encoder; a second average speed calculating part for calculating the average speed using at least the current calculated speed, which is calculated by the second speed calculating part, and a calculated speed which has been m (m≧2) before; and a second differentiating element which operates on the basis of a speed deviation of the output of the second average speed calculating part from the target speed.
- The motor may be a DC motor.
- According to another aspect of the present invention, there is provided a method for controlling a motor for use in a printer, the method comprising the steps of: detecting the speed of a motor for use in a printer in a predetermined period tv; calculating an average speed using at least the current detected speed and a detected speed which has been detected n (≧2), which corresponds to substantially half period of the fluctuation in speed of the motor, before the timing in detecting the current detected speed; and controlling the speed of the motor on the basis of a speed deviation of the average speed from a target speed of the motor.
- In this control method, assuming that the period of the fluctuation in speed of the motor is Tv, the number n used for calculating the average speed preferably meets the following expression.
- T v/(2t v)−2≦n<T v/(2t v)+2
- Preferably, the step of controlling the speed of the motor controls the speed of the motor on the basis of the sum of the speed deviation and the output of a differentiating element which operates on the basis of the speed deviation.
- According to a further aspect of the present invention, there is provided a computer-readable storage medium storing control program code for controlling a motor for use in a printer, comprising: first program code means for detecting the speed of a motor for use in a printer in a predetermined period tv; second program code means for calculating an average speed using at least the current detected speed and a detected speed which has been detected n (≧2), which corresponds to substantially half period of the fluctuation in speed of the motor, before the timing in detecting the current detected speed; and third program code means for controlling the speed of the motor on the basis of a speed deviation of the average speed from a target speed of the motor.
- The present invention will be understood more fully from the detailed description given herebelow and from the accompanying drawings of the preferred embodiments of the invention. However, the drawings are not intended to imply limitation of the invention to a specific embodiment, but are for explanation and understanding only.
- In the drawings:
- FIG. 1 is a block diagram showing the construction of the first preferred embodiment of a control unit for controlling a motor for use in a printer according to the present invention;
- FIG. 2 is a graph showing the fluctuation in speed for explaining effects in the first preferred embodiment;
- FIG. 3 is a waveform illustration showing the fluctuation in speed of a CR motor;
- FIG. 4 is a schematic diagram for explaining the driving of a carriage;
- FIG. 5 is a block diagram showing the construction of the second preferred embodiment of a control unit for controlling a motor for use in a printer according to the present invention;
- FIG. 6 is a block diagram schematically showing the construction of an ink jet printer;
- FIG. 7 is a perspective view showing the peripheral construction of a carriage;
- FIG. 8 is a schematic view showing the construction of a linear type encoder;
- FIGS.9(a) and 9(b) are waveform illustrations of output pulses of an encoder;
- FIG. 10 is a schematic perspective view of a printer for explaining the position of a paper detecting sensor;
- FIG. 11 is a block diagram showing the construction of a typical speed control unit for use in an ink jet printer;
- FIGS.12(a) and 12(b) are waveform illustrations for explaining the operation of the speed control unit shown in FIG. 11;
- FIG. 13 is a schematic diagram showing the construction of a typical DC motor;
- FIG. 14 is a flow chart showing a control procedure in a method for controlling a motor for use in a printer according to the present invention;
- FIG. 15 is a perspective view showing an example of a computer system using a storage medium, in which a print control program has been recorded, according to the present invention; and
- FIG. 16 is a block diagram showing an example of a computer system using a storage medium, in which a print control program has been recorded, according to the present invention.
- Referring now to the accompanying drawings, the preferred embodiments of the present invention will be described below.
- First, the schematic construction and control of an ink jet printer, which uses a control unit for controlling a motor for use in a printer according to the present invention, will be described. The schematic construction of this ink jet printer is shown in FIG. 6.
- This ink jet printer comprises: a paper feed motor (which will be also hereinafter referred to as a PF motor)1 for feeding a paper; a paper feed motor driver 2 for driving the paper feed motor 1; a carriage 3; a carriage motor (which will be also hereinafter referred to as a CR motor) 4; a CR motor driver 5 for driving the carriage motor 4; a DC unit 6; a pump motor 7 for controlling the suction of ink for preventing clogging; a pump motor driver 8 for driving the pump motor 7; a recording head 9, fixed to the carriage 3, for discharging ink to a printing paper 50; a head driver 10 for driving and controlling the recording head 9; a linear type encoder 11 fixed to the carriage 3; a code plate 12 which has slits in regular intervals; a rotary type encoder 13 for use in the PF motor 1; a paper detecting sensor 15 for detecting the position of the rear edge of a paper which is being printed; a CPU 16 for controlling the whole printer; a timer IC 17 for periodically generating an interruption signal to output the signal to the CPU 16; an interface part (which will be also hereinafter referred to as an IF) 19 for transmitting/receiving data to/from a host computer 18; an ASIC 20 for controlling the printing definition, the driving waveform of the recording head 9 and so forth on the basis of printing information which is fed from the host computer 18 via the IF 19; a PROM 21, RAM 22 and EEPROM 23 which are used as working and program storing regions for the ASIC 20 and the CPU 16; a platen 25 for supporting the paper 50 during print; a carrier roller 27, driven by the PF motor 1, for carrying the printing paper 50; a pulley 30 mounted on the rotating shaft of the CR motor 4; and a timing belt 31 driven by the pulley 30.
- Furthermore, the
DC unit 6 is designed to drive and control the paperfeed motor driver 2 and theCR motor driver 5 on the basis of a control command, which is fed from theCPU 16, and the outputs of theencoders paper feed motor 1 and theCR motor 4 comprises a DC motor. - The peripheral construction of the
carriage 3 of this ink jet printer is shown in FIG. 7. - The
carriage 3 is connected to thecarriage motor 4 via thetiming belt 31 and thepulley 30 to be driven so as to be guided by aguide member 32 to move in parallel to theplaten 25. Thecarriage 3 is provided with therecording head 9 on the surface facing the printing paper. Therecording head 9 comprises a nozzle row for discharging a black ink and a nozzle row for discharging color inks. Each nozzle is supplied with ink from anink cartridge 34, and discharges drops of ink to the printing paper to print characters and/or images. - In a non-print region of the
carriage 3, there are provided acapping unit 35 for sealing a nozzle opening of therecording head 9 during non-print, and apump unit 36 having thepump motor 7 shown in FIG. 6. When thecarriage 3 moves from a print region to the non-print region, thecarriage 3 contacts a lever (not shown) to move thecapping unit 35 upwards to seal therecording head 9. - When the nozzle opening row of the
recording head 9 is clogged with ink, or when thecartridge 34 is exchanged or the like to force therecording head 9 to discharge ink, thepump unit 36 is operated in the sealed state of therecording head 9, to suck ink out of the nozzle opening row by a negative pressure from thepump unit 36. Thus, dust and paper powder adhering to a portion near the nozzle opening row are cleaned. Moreover, bubbles of therecording head 9, together with ink, are discharged to acap 37. - Then, the construction of the
linear type encoder 11 mounted on thecarriage 3 is shown in FIG. 8. Thisencoder 11 comprises alight emitting diode 11 a, acollimator lens 11 b, and adetection processing part 11 c. Thedetection processing part 11 c has a plurality of (four)photodiodes 11 d, asignal processing circuit 11 e, and two comparators 11 f A and 11 f B. - If a voltage VCC is applied between both ends of the
light emitting diode 11 a via a resistor, light rays are emitted from thelight emitting diode 11 a. The light rays are collimated by thecollimator lens 11 b to pass through thecode plate 12. Thecode plate 12 is provided with slits at regular intervals (e.g., every {fraction (1/180)} inches (={fraction (1/180)}×2.54 cm)). - The parallel rays passing through the
code plate 12 are incident on each of the photodiodes lid via a fixed slit (not shown), and converted into electric signals. The electric signals outputted from the fourphotodiodes 11 d are processed by thesignal processing circuit 11 e. The signals outputted from thesignal processing circuit 11 e are compared by the comparators 11 f A and 11 f B, and the compared results are outputted as pulses. The pulses ENC-A and ENC-B outputted from the comparators 11 f A and 11 f B are outputs of theencoder 11. - The phase of the pulse ENC-A is different from the phase of the pulse ENC-B by 90 degrees. The
encoder 4 is designed so that the phase of the pulse ENC-A is advanced from the pulse ENC-B by 90 degrees as shown in FIG. 9(a) when theCR motor 4 is normally rotating, i.e., when thecarriage 3 is moving a main scanning direction, and the phase of the pulse ENC-A lags behind the pulse ENC-B by 90 degrees as shown in FIG. 9(b) when theCR motor 4 is reversely rotating. One period T of the pulses corresponds to the distance between adjacent slits of the code plate 12 (e.g., {fraction (1/180)} inches (={fraction (1/180)}×2.54 cm)). This is equal to a period of time, in which thecarriage 3 moves between the adjacent slits. - On the other hand, the
rotary type encoder 13 for use in thePF motor 1 has the same construction as that of thelinear type encoder 11, except that the code plate is a rotating disk which rotates in accordance with the rotation of thePF motor 1. Furthermore, in the ink jet printer, the distance between adjacent slits of a plurality of slits provided in the code plate of theencoder 13 for use in the PF motor is {fraction (1/180)} inches ({fraction (1/180)}×2.54 cm). When thePF motor 1 rotates by the distance between adjacent slits, the paper is fed by {fraction (1/1440)} inches (={fraction (1/1440)}×2.54 cm). - Referring to FIG. 10, the position of the
paper detecting sensor 15 shown in FIG. 6 will be described below. - In FIG. 10, the
paper 10 inserted into apaper feeding port 61 of aprinter 60 is fed into theprinter 60 by means of apaper feeding roller 64 which is driven by apaper feeding motor 63. The front edge of thepaper 50, which has been fed into theprinter 60, is detected by, e.g., an opticalpaper detecting sensor 15. Thepaper 50, the front edge of which has been detected by thepaper detecting sensor 15, is fed by means of apaper feed roller 65 and a drivenroller 66 which are driven by thePF motor 1. - Subsequently, ink drops from the recording head (not shown), which is fixed to the
carriage 3 moving along thecarriage guide member 32, to carry out a print. Then, when the paper is fed to a predetermined position, the rear edge of thepaper 50, which is currently being printed, is detected by thepaper detecting sensor 15. Then, agear 67 c is driven, via agear 67 b, by means of agear 67 a which is driven by thePF motor 1. Thus, apaper discharging roller 68 and a drivenroller 69 are rotated to discharge the printedpaper 50 from apaper discharging port 62 to the outside. - Referring to FIGS. 11 and 12, an example of the speed control of the
DC motor 4 using theDC unit 6 shown in FIG. 6 will be described below. - The
DC unit 6 comprises aposition calculating part 6 a, a subtracter-6 b, a targetspeed calculating part 6 c, aspeed calculating part 6 d, asubtracter 6 e, aproportional element 6 f, an integratingelement 6 g, a differentiatingelement 6 h, anadder 6 i, a D/A converter 6 j, atimer 6 k, and anacceleration control part 6 m. - The
position calculating part 6 a is designed to detect the leading and trailing edges of each of the output pulses ENC-A and ENC-B of theencoder 11 to count the number of the detected edges, and to calculate the position of thecarriage 3 on the basis of the counted value. In this counting, when theCR motor 4 is normally rotating, if one edge is detected, “+1” is added, and when theCR motor 4 is reversely rotating, if one edge is detected, “−1” is added. Each of the periods of the pulses ENC-A and ENC-B is equal to the distance between adjacent slits of thecode plate 12, and the phase of the pulse ENC-A is different from the phase of the pulse ENC-B by 90 degrees. Therefore, the counted value “1” in the above described counting corresponds to ¼ of the distance between adjacent slits of thecode plate 12. Thus, if the counted value is multiplied by ¼ of the distance between adjacent slits, it is possible to obtain the moving amount of thecarriage 3 from a position corresponding to a counted value “0”. At this time, the definition of theencoder 11 is ¼ of the distance between adjacent slits of thecode plate 12. If the distance between adjacent slits is {fraction (1/180)} inches (={fraction (1/180)}×2.54 cm), the definition is {fraction (1/720)} inches (={fraction (1/720)}×2.54 cm). - The
subtracter 6 b is designed to calculate a position deviation of the actual position of thecarriage 3, which is obtained by theposition calculating part 6 a, from a target position which is fed from theCPU 16. - The target
speed calculating part 6 c is designed to calculate a target speed of thecarriage 3 on the basis of the position deviation which is the output of thesubtracter 6 b. This operation is carried out by multiplying the position deviation by a gain Kp. This gain Kp is determined in accordance with the position deviation. Furthermore, the value of the gain Kp may be stored in a table (not shown). - The
speed calculating part 6 d is designed to calculate a speed of thecarriage 3 on the basis of the output pulses ENC-A and ENC-B of theencoder 11. This speed is obtained as follows. First, the leading and trailing edges of each of the output pulses ENC=A and ENC-B of theencoder 11 are detected, and the time interval between the edges corresponding to ¼ of the distance between adjacent slits of thecode plate 12 is counted by, e.g., a timer counter. Assuming that the counted value is T and that the distance between adjacent slits of thecode plate 12 is λ, the speed of the carriage is λ/(4T). Furthermore, in this preferred embodiment, the speed of the carriage is obtained by counting one period of the output pulse ENC-A, e.g., the period between the leading edge and the next leading edge, by means of a timer counter. - The
subtracter 6 e is designed to calculate a speed deviation of the actual speed of thecarriage 3, which is calculated by thespeed calculating part 6 d, from a target speed. - The
proportional element 6 f is designed to multiply the speed deviation by a constant Gp to output the multiplied result. The integratingelement 6 g is designed to integrate a value which is obtained by multiplying the speed deviation by a constant Gi. The differentiatingelement 6 h is designed to multiply a difference between the current speed deviation and the last speed variation by a constant Gd to output the multiplied result. Furthermore, the operations in theproportional element 6 f, integratingelement 6 g and differentiatingelement 6 h are carried out every one period of the output pulse ENC-A of theencoder 11, i.e., in synchronism with the leading edge of the output pulse ENC-A. - The outputs of the
proportional element 6 f, integratingelement 6 g and differentiatingelement 6 h are added by theadder 6 i. Then, the added result, i.e., the driving current of theCR motor 4, is fed to the D/A converter 6 j to be converted into an analog current. On the basis of the analog current, theCR motor 4 is driven by thedriver 5. - In addition, the
timer 6 k and theacceleration control part 6 m are used for controlling acceleration, and the PID control using theproportional element 6 f, integratingelement 6 g and differentiatingelement 6 h is used for controlling the constant speed and deceleration during acceleration. - The
timer 6 k is designed to generate a timer interruption signal every a predetermined time on the basis of a clock signal which is fed from theCPU 16. - The
acceleration control part 6 m is designed to integrate a predetermined current value (e.g., 20 mA) into a target current value every time it receives the timer interruption signal, and to feed the integrated result, i.e., the target current value of theDC motor 4 during acceleration, to the D/A converter 6 j. Similar to the PID control, the target current value is converted into an analog current by the D/A converter 6 j. On the basis of this analog current, theCR motor 4 is driven by the driver. - The
driver 5 has, e.g., four transistors. By turning each of the transistors ON and OFF on the basis of the output of the D/A converter 6 j, thedriver 5 can be selectively in (a) an operation mode in which theCR motor 4 is normally or reversely rotated, (b) a regenerative brake operation mode (a short brake operation mode, i.e., a mode in which the stopping of the CR motor is maintained), or (c) a mode in which the CR motor is intended to be stopped. - Referring to FIGS.12(a) and 12(b), the operation of the
DC unit 6 will be described below. - If a start-up command signal for starting the
CR motor 4 is fed from theCPU 16 to theDC unit 6 when theCR motor 4 is stopped, a start-up initial current value Io is fed from theacceleration control part 6 m to the D/A converter 6 j. Furthermore, this start-up initial current value Io, together with the start-up command signal, is fed from theCPU 16 to theacceleration control part 6 m. Then, this current value Io is converted into an analog current by the D/A converter 6 j to be fed to thedriver 5, and the CR motor is started up by the driver 5 (see FIG. 12(a), 12(b)). - After the start-up command signal is received, the
timer 6 k generates a timer interruption signal every a predetermined time. Every time theacceleration control part 6 m receives the timer interruption signal, theacceleration control part 6 m integrates a predetermined current value (e.g., 20 mA) into the start-up initial current value Io, to feed the integrated current value to the D/A converter 6 j. Then, the integrated current value is converted into an analog current by the D/A converter 6 j to be fed to thedriver 5. Then, the CR motor is driven by thedriver 5 so that the value of the current supplied to theCR motor 4 is the integrated current value, so that the speed of theCR motor 4 increases (see FIG. 12(b)). Therefore, the current value supplied to the CR motor is step-wise as shown in FIG. 12(a). - Furthermore, at this time, although the PID control system also operates, the D/
A converter 6 j selects and incorporates the output of theacceleration control part 6 m. - The integration of the current value in the
acceleration control part 6 m is carried out until the integrated current value becomes a constant current value Is. When the integrated current value becomes the predetermined value Is at time t1, theacceleration control part 6 m stops the integration, and supplies the constant current value Is to the D/A converter 6 j. Thus, theCR motor 4 is driven by thedriver 5 so that the value of the current supplied to theCR motor 4 becomes the current value Is (see FIG. 12(a)). - Then, in order to prevent the speed of the
CR motor 4 from overshooting, theacceleration control part 6 m controls theCR motor 4 so as to reduce the current, which is supplied to theCR motor 4, when the speed of theCR motor 4 becomes a predetermined speed V1 (see time t2). At this time, the speed of theCR motor 4 further increases. However, when the speed of theCR motor 4 reaches a predetermined speed Vc (see time t3 in FIG. 12(b)), the D/A converter 6 j selects the output of the PID control system, i.e., the output of theadder 6 i, to carry out the PID control. - That is, the target speed is calculated on the basis of the position deviation of the actual position, which is obtained from the output of the
encoder 11, from the target position. In addition, theproportional element 6 f, integratingelement 6 g and differentiatingelement 6 h are operated on the basis of the speed deviation of the actual speed, which is obtained from the output of theencoder 11, from the target speed to carry out the proportional, integrating and differentiating operations. Moreover, theCR motor 4 is controlled on the basis of the sum of these calculated results. Furthermore, the above described proportional, integrating and differentiating operations are carried out in synchronism with, e.g., the leading edge of the output pulse ENC-A of theencoder 11. Thus, the speed of theDC motor 4 is controlled so as to be a desired speed VΘ. Furthermore, the predetermined speed Vc is preferably a value of 70% to 80% of the desired speed VΘ. - Since the speed of the
DC motor 4 is the desired speed VΘafter time t4, a printing processing can be carried out. When the printing processing is completed and when thecarriage 3 reaches the target position (see time t5 in FIG. 12(b)), theDC motor 4 is decelerated to be stopped at time t6. - (First Preferred Embodiment)
- The construction of the first preferred embodiment of a control unit for controlling a motor for use in a printer according to the present invention is shown in FIG. 1. The control unit in this preferred embodiment is used for controlling a
carriage motor 4 comprising a DC motor for use in an ink jet printer, and comprises aDC unit 80. TheDC unit 80 includes an averagespeed measuring part 90, which is substituted for thespeed calculating part 6 d of theDC unit 6 shown in FIG. 11, and asubtracter 96 which is newly provided. - The average
speed measuring part 90 comprises aspeed calculating part 91, amemory 92, and an averagespeed calculating part 93. Thespeed calculating part 91 has the same construction as that of thespeed calculating part 6 d shown in FIG. 11. Thespeed calculating part 91 is designed to calculate a speed of theCR motor 4, i.e., a speed of thecarriage 3, on the basis of the output of theencoder 11. - This operation is carried out in synchronism with the leading edge of the output pulse ENC-A of the
encoder 11. - The
memory 92 is designed to store therein n speed data from the last calculated result to a calculated result of n (n≧1) before, which have been calculated by thespeed calculating part 91. After the averagespeed calculating part 93 reads n speed data, thememory 92 is designed to store therein the current speed which is calculated by thespeed calculating part 91 in place of the calculated speed of n before. - The average
speed calculating part 93 is designed to calculate an average of two speed data of the current speed data, which are calculated by thespeed calculating part 91, and speed data of n before, which have been stored in thememory 92. - The
subtracter 6 e is designed to calculate a speed deviation of the current speed, which is calculated by thespeed calculating part 91, from a target speed, which is the output of the targetspeed calculating part 6 c, to transmit the calculated speed deviation to the integratingelement 6 g. - The
subtracter 96 is designed to calculate a speed deviation of the average speed, which is the output of the averagespeed calculating part 93, from the target speed, which is the output of the targetspeed calculating part 6 c, to transmit the calculated speed deviation to theproportional element 6 f and the differentiatingelement 6 h. - The
proportional element 6 f is designed to multiply the output of thesubtracter 96 by a constant Gp to transmit the multiplied result to theadder 6 i. The integratingelement 6 g is designed to integrate a value, which has been obtained by multiplying the output of thesubtracter 6 e by a constant Gi, to transmit the integrated result to theadder 6 i. The differentiatingelement 6 h is designed to multiply a difference between the current speed deviation and the last speed deviation by a constant Gd to transmit the multiplied result to theadder 6 i. Furthermore, the operations in theproportional element 6 f, integratingelement 6 g and differentiatingelement 6 h are carried out in synchronism with the leading edge of the output pulse ENC-A of theencoder 11. - The outputs of the
proportional element 6 f, integratingelement 6 g and differentiatingelement 6 h are added up by theadder 6 i. Then, the added result, i.e., the current for driving theCR motor 4 which causes the above described speed deviation to be zero, is fed to the D/A converter 6 j to be converted an analog current. On the basis of this analog current, theCR motor 4 is driven by thedriver 5. - In this preferred embodiment, the number n used for calculating the average speed approximates to Tv/(2tv) assuming that the period of the fluctuation in speed of the
CR motor 4 is Tv and that the period of the operation of the speed in thespeed calculating part 91 is tv. By thus causing the number n to approximate to Tv/(2tv), the fluctuation in speed of theCR motor 4 can be suppressed. - Referring to FIGS. 2 and 3, this will be described. In this preferred embodiment, it is assumed that the number of poles of the
CR motor 4 is 5, that the effective diameter length (i.e., the pitch circle length) L of thepulley 30, mounted on the rotating shaft of theCR motor 4, for driving thetiming belt 31 is 26 mm, and that the distance A between adjacent slits of thecode plate 12 of theencoder 11 is {fraction (1/180)} inches (=0.14 mm). Then, the fluctuation in speed of theCR motor 4 occurs 10 times every one rotation, i.e., 10 times while thecarriage 3 moves by 26 mm, so that the period Tv of the fluctuation in speed is equal to a period of time, in which thecarriage 3 moves by 2.6 mm (=26 mm/(2×5)). - On the other hand, the operation period tv of the
speed calculating part 91 is equal to the period of the output pulse ENC-A of theencoder 11, i.e., a period of time, in which thecarriage 3 moves by the distance between adjacent slits (=0.14 mm) of thecode plate 12. - Therefore, in one period of the fluctuation in speed of the
CR motor 4, Tv/tv=18.4 (=2.6 mm/0.14 mm) speed operations are carried out by thespeed calculating part 91. - In such conditions, assuming that the speed of the rotating shaft of the
CR motor 4 fluctuates as a sinusoidal wave about a predetermined speed VΘand that the number n used for calculating the average speed by the averagespeed calculating part 93 is a parameter, the state of the output of the average speed calculating part in this preferred embodiment is shown in FIG. 2. Furthermore, in FIG. 2, only the fluctuating part in speed is normalized. - In FIG. 2, a graph g1 shows the state of the fluctuation in speed when n=0, i.e., when the output of the average
speed calculating part 93 is coincident with the output of thespeed calculating part 91, and a graph g2 shows the state of the fluctuation in speed when n=7, i.e., the fluctuation in average speed of the current calculated speed and a calculated speed of 7 before. In addition, a graph g3 shows the state of the fluctuation in speed when n=8, i.e., the fluctuation in average speed of the current calculated speed and a calculated speed of 8 before, and a graph g4 shows the state of the fluctuation in speed when n=9, i.e., the fluctuation in average speed of the current calculated speed and a calculated speed of 9 before. Moreover, a graph g5 shows the state of the fluctuation in speed when n=10, i.e., the fluctuation in average speed of the current calculated speed and a calculated speed of 10 before, and a graph g6 shows the state of the fluctuation in speed when n=11, i.e., the fluctuation in average speed of the current calculated speed and a calculated speed of 11 before. - As can be seen from the calculated results shown in FIG. 2, when n=9, i.e., when n approximates to Tv/(2tv) (=9.2), the fluctuation in speed is smallest. It is considered that the reason for this is that if the product ntv of the operation period tv of the
speed calculating part 91 and the number n is about half of the period Tv of the fluctuation in speed of theCR motor 4, the average speed calculated by the averagespeed calculating part 93 approximates to zero as shown in FIG. 3, so that the fluctuation in speed decreases. - Therefore, it is possible to suppress the fluctuation in speed if the number n used for calculating the average speed meets the following expression.
- T v/(2t v)−2≦n<T v/(2t v)+2
- Furthermore, in practice, as shown in FIG. 4, the
timing belt 31 is stretched at a tension between thepulley 30, which is driven by theCR motor 4, and the drivenwheel 30 a which is driven by thepulley 30, so that the fluctuation in speed of theCR motor 4 is lately transmitted to thecarriage 3. Therefore, as can be seen from FIG. 2, it is considered that the use of n=10, in which the phase is advanced, is more effective in the suppression of the fluctuation in speed of theCR motor 4 although the fluctuation in speed is slightly greater than that when n=9. - Therefore, assuming that the distance between adjacent slits of the
code plate 12 of theencoder 11 is λ, that the pitch circle length (the effective diameter length) of thepulley 30 is L, and that the number of phases of theCR motor 4 is p, then, the number n used for calculating the average speed preferably meets the following expression. - L/(4pλ)≦n<L/(4pλ)+2
- Furthermore, assuming that the period of the fluctuation in speed of the
CR motor 4 is Tv and that the operation period of thespeed calculating part 91 is tv, the following expression is satisfied. - L/(4pλ)=(L/(2p))/(2λ)=T v/(2t v)
- As described above, according to this preferred embodiment, it is possible to suppress the fluctuation in speed of the CR motor.
- Furthermore, while the speed deviation serving as the deviation of the average speed from the target speed has been inputted to the
proportional element 6 f and the differentiatingelement 6 f in this preferred embodiment, the same effects can be obtained if the speed deviation is inputted to only the differentiatingelement 6 h and if the speed deviation of the output of thespeed calculating part 91 from the target speed is inputted to theproportional element 6 f and the integratingelement 6 f. In addition, the same effects can be obtained if the speed deviation of the average speed from the target speed is inputted to all of theproportional element 6 f, the integratingelement 6 g and the differentiatingelement 6 h. - Furthermore, while the
position calculating part 6 a has counted the leading and trailing edges of the output pulses ENC-A and ENC-B of theencoder 11 to multiply the counted value by the distance between adjacent slits of thecode plate 12 of theencoder 11, the leading and trailing edges of the output pulses ENC-A and ENC-B may be counted without the multiplication by the distance between adjacent slits, to be outputted. In this case, the target position is also expressed by the number of pulses, and the output of thespeed calculating part 91 is the inverse number of the period of the output pulse ENC-A of theencoder 11. In addition, the averagespeed calculating part 93 calculates an average value of the inverse number of the period of the output pulse ENC-A to output the calculated average value. - In addition, while the average
speed calculating part 93 has calculated the average speed of the current calculated speed and the calculated speed of n before in the above described first preferred embodiment, the average value (the average speed) of k+1 calculated speed data from the current calculated speed to a calculated speed of k (n>k≧1) before and k+1 calculated speed data from a calculated speed of n before and a calculated speed of n+k before may be obtained. In this case, n+k calculated speed data from the last calculated speed to the calculated speed of n+k before are stored in thememory 92. With this construction, it is possible to suppress the influence of noises. - In addition, the average
speed calculating part 93 may be designed to obtain an average value of m (n−1≧m≧2) calculated speed data, which are selected from n calculated speed data from the current calculated speed to a calculated speed of n−1 before and which include the current calculated speed, and m calculated speed data which are selected from n calculated speed data from a calculated speed of n before to a calculated speed of 2n−1 and which correspond to the m calculated speed data. The calculated speed data corresponding to the current calculated speed data are the calculated speed data of n before, and the calculated speed data corresponding to the calculated speed data of k (n−1≧k≧1) before are the calculated speed data of n+k before. - In addition, in the above described preferred embodiment, while the value approximating to Tv/(2tv)=L/(4pλ)=πD/(4λ) has been selected as the number n used for calculating the average speed assuming that the number of phases of the
CR motor 4 is p, that the effective length of thepulley 30 is L (=πD (D is a pitch circle diameter)), that the period of the fluctuation in speed of theCR motor 4 is Tv , that the operation period of thespeed calculating part 91 is tv and that the distance between adjacent slits of theencoder 11 is λ, n may be fixed to a predetermined value, and the pitch circle diameter D may be a value meeting the above described relationship. - Furthermore, in the ink jet printer, the speed of the
carriage 3 fluctuates under the influence of (a) the fluctuation in speed of theCR motor 4, (b) the fluctuation in speed of thetiming belt 31, and (c) the fluctuation in speed of the pulley. Therefore, it is not only required to suppress the fluctuation in speed of theCR motor 4, but it is also required to suppress the fluctuation in speed due to other factors. In the following second preferred embodiment, the fact that the fluctuation in speed due to other factors can be suppressed will be described below. - (Second Preferred Embodiment)
- The construction of the second preferred embodiment of a control unit for controlling a motor for use in a printer according to the present invention is shown in FIG. 5. The control unit in this second preferred embodiment is used for controlling the speed of a CR motor of an ink jet printer. In this preferred embodiment, a
DC unit 80A is substituted for theDC unit 80 of the control unit in the first preferred embodiment shown in FIG. 1. TheDC unit 80A has an averagespeed measuring part 90A, asubtracter 97 and a differentiatingelement 98 which are newly added to theDC unit 80 shown in FIG. 1. - The average
speed measuring part 90A has substantially the same construction as that of the averagespeed measuring part 90, and comprises aspeed calculating part 91A, amemory 92A and an averagespeed calculating part 93A. - The
speed calculating part 91A has the same construction as that of thespeed calculating part 91, and is designed to calculate the speed of theCR motor 4, i.e., the speed of thecarriage 3, on the basis of the output pulse ENC-A of theencoder 11. This operation is carried out in synchronism with the leading edge of the output pulse ENC-A of theencoder 11. - The
memory 92A is designed to store therein m speed data from the last calculated result to the calculated result of m (m≧2) before, which are calculated by thespeed calculating part 91A. After the averagespeed calculating part 93A reads data of m before, thememory 92A is designed to store therein the current calculated speed, which is calculated by thespeed calculating part 91A, in place of the calculated speed of m before. - The average
speed calculating part 93A is designed to calculate an average value (an average speed) of the current speed data, which are calculated by thespeed calculating part 91A, and the calculated speed of m before, to transmit the calculated result to thesubtracter 97. - The
subtracter 97 is designed to calculate a speed deviation of the average speed, which is the output of the averagespeed calculating part 93A, from the target speed which is the output of the target speed calculating means 6 c. - The differentiating
element 98 is designed to multiply the difference between the current speed deviation and the last speed deviation by a constant GdA, to transmit the multiplied result to theadder 6 i. - Then, the sum of the outputs of the
proportional element 6 f, integratingelement 6 g, differentiatingelement 6 h and differentiatingelement 98 is calculated by theadder 6 i. The output of theadder 6 i, i.e., the driving current for theCR motor 4 which causes the speed deviation to be zero, is fed to the D/A converter 6 j to be converted an analog current. On the basis of this analog current, theCR motor 4 is driven by thedriver 5. - In this preferred embodiment, the number m used for calculating the average speed approximates to TvA/(2tvA) assuming that the period of the fluctuation in speed to be suppressed other than the fluctuation in speed of the
CR motor 4 is TvA and that the operation period in thespeed calculating part 91A is tvA. - As described above, the control unit in this second preferred embodiment can suppress the fluctuation in speed of the
CR motor 4, and can also suppress the fluctuation in speed due to other factors. - Furthermore, in the second preferred embodiment, the operation period of the
speed calculating part 91A has been equal to the period of the output pulse ENC-A of theencoder 11. However, when the period of the fluctuation in speed to be suppressed is shorter than the period of the fluctuation in speed of the CR motor, the operation of thespeed calculating part 91A is preferably carried out in synchronism with the leading and trailing edges of each of the output pulses ENC-A and ENC-B of the encoder, or on the basis of the output pulse of a higher definition encoder. - In addition, in the second preferred embodiment, the average
speed calculating part 93A has calculated the average speed of the current calculated speed and the calculated speed of m before. However, the average value (the average speed) of k+1 calculated speed data from the current calculated speed to the calculated speed of k (m>k≧1) before and k+1 calculated speed data from the calculated speed of m before to the calculated speed of m+k before may be obtained. In this case, thememory 92 stores therein m+k calculated speed data from the last calculated speed to the calculated speed of m+k before. - Furthermore, the DC motor has been described in the above described first and second preferred embodiments, the present invention can also be applied to an AC motor.
- (Third Preferred Embodiment)
- Referring to FIG. 14, the third preferred embodiment of the present invention will be described below. This third preferred embodiment relates to a method for controlling a motor for use in a printer, and the control procedure thereof is shown in FIG. 14.
- First, the speed of a motor for use in a printer, e.g., the speed of a carriage motor, is detected in a predetermined period tv to be stored (see step F1 in FIG. 14). Then, an average speed is calculated using at least the current detected speed and a detected speed which has been detected n (n≧2), which corresponds to substantially half period in the fluctuation in speed of the motor, before the timing in detecting the current detected speed (see step F2 in FIG. 14). Subsequently, the speed of the motor is controlled on the basis of the speed deviation of the average speed from the target speed (see step F3 in FIG. 14).
- According to the above described control method in this preferred embodiment, the influence of the fluctuation in speed is removed from the calculated average speed, so that the fluctuation in speed can be suppressed by controlling the speed of the motor on the basis of the speed deviation of the average speed from the target speed.
- Furthermore, at the step of calculating the average speed, the average speed of k+1 detected speeds from the current detected speed to the detected speed of k (n>k≧0) before and k+1 detected speeds from the detected speed of n before to the detected speed of n+k before may be obtained.
- In addition, at the step of controlling the speed of the motor, the motor may be controlled on the basis of the sum of the speed deviation and the output of the differentiating element which is operated on the basis of the speed deviation.
- (Fourth Preferred Embodiment)
- Referring to FIGS. 15 and 16, the fourth preferred embodiment of the present invention will be described below. This preferred embodiment relates to a storage medium, in which a control program for controlling a motor for use in a printer has been stored. FIGS. 15 and 16 are a perspective view and block diagram showing an example of a
computer system 130 which uses a storage medium, in which a print control program in this preferred embodiment has been recorded. - In FIG. 15, the
computer system 130 comprises acomputer body 130 including a CPU, adisplay unit 132, such as a CRT, aninput unit 133, such as a keyboard or mouse, and aprinter 134 for carrying out a print. - As shown in FIG. 16, the
computer body 131 comprises aninternal memory 135 of a RAM, and a built-in orexterior memory unit 136. As thememory unit 136, a flexible or floppy disk (FD) drive 137, a CD-ROM drive 138 and a hard disk drive (HD)unit 139 are mounted. As shown in FIG. 15, a flexible disk or floppy disk (FD) 141 which is inserted into a slot of the FD drive 137 to be used, a CD-ROM 142 which is used for the CD-ROM drive 138, or the like is used as astorage medium 140 for use in thememory unit 136. - As shown in FIGS. 15 and 16, it is considered that the
FD 141 or the CD-ROM 142 is used as the storage medium for use in a typical computer system. However, since this preferred embodiment relates to a control program for controlling a motor for use in theprinter 134, the control program of the present invention may be recorded in, e.g., aROM chip 143 serving as a nonvolatile memory which is built in theprinter 134. Of course, the storage medium may be any one of FDs, CD-ROMs, MOs (Magneto-Optical) disks, DVDs (Digital Versatile Disks), other optical recording disks, card memories, and magnetic tapes. - The
storage medium 140 in this preferred embodiment is designed to carry out a control procedure including steps F1 through F3 shown in FIG. 14. That is, thestorage medium 140 in this preferred embodiment may carry out the steps of detecting the speed of a motor in a predetermined period tv, calculating an average speed using at least the current detected speed and a detected speed which has been detected n (n≧2), which corresponds to substantially half period in the fluctuation in speed of the motor, before the timing in detecting the current detected speed, and controlling the speed of the motor on the basis of a speed deviation of the average speed from the target speed. - As described above, according to the present invention, it is possible to suppress the fluctuation in speed of a motor for use in a printer.
- While the present invention has been disclosed in terms of the preferred embodiment in order to facilitate better understanding thereof, it should be appreciated that the invention can be embodied in various ways without departing from the principle of the invention. Therefore, the invention should be understood to include all possible embodiments and modification to the shown embodiments which can be embodied without departing from the principle of the invention as set forth in the appended claims.
Claims (18)
1. A control unit for controlling a motor for use in a printer, said control unit comprising:
a speed detecting part for detecting the speed of a motor for use in a printer in a predetermined period tv;
an average speed calculating part for calculating an average speed using at least the current detected speed, which is detected by said speed detecting part, and a detected speed which has been detected n (≧2), which corresponds to substantially half period of the fluctuation in speed of said motor, before the timing in detecting said current detected speed; and
a speed control part for controlling the speed of said motor on the basis of a speed deviation of said average speed, which is the output of said average speed calculating part, from a target speed of said motor.
2. A control unit for controlling a motor for use in a printer, as set forth in claim 1 , wherein assuming that the period of the fluctuation in speed of said motor is Tv, the number n used for calculating said average speed meets the following expression.
T v/(2t v)−2≦n<T v/(2t v)+2
3. A control unit for controlling a motor for use in a printer, as set forth in claim 2 , wherein said average speed calculating part calculates an average speed of k+1 detected speeds from the current detected speed to a detected speed of k (n>k≧0) before, and k+1 detected speeds from a detected speed of n before to a detected speed of k+1 before.
4. A control unit for controlling a motor for use in a printer, as set forth in claim 3 , wherein said speed control part has a differentiating element which operates on the basis of said speed deviation of said average speed from said target speed.
5. A control unit for controlling a motor for use in a printer, as set forth in claim 4 , wherein said speed control part has a proportional element which operates on the basis of said speed deviation of said average speed from said target speed.
6. A control unit for controlling a motor for use in a printer, as set forth in claim 5 , wherein said speed detecting part comprises an encoder for generating an output pulse in accordance with the rotation of said motor, and a speed calculating part for calculating the speed of said motor in a period of said output pulse on the basis of said output pulse of said encoder.
7. A control unit for controlling a motor for use in a printer, as set forth in claim 6 , wherein said motor is a carriage motor for use in an ink jet printer, and said encoder generates said output pulse in accordance with the movement of a carriage driven by said carriage motor via a pulley, which is mounted of the rotating shaft of said carriage motor, and via a timing belt which is driven by said pulley.
8. A control unit for controlling a motor for use in a printer, as set forth in claim 7 , wherein assuming that the distance between adjacent slits of a code plate of said encoder is λ, that a pitch circle length of said pulley is L and that the number of phases of said motor is p, said n meets the following expression.
L/(4pλ)≦n<L/(4pλ)+2
9. A control unit for controlling a motor for use in a printer, as set forth in claim 7 , wherein said speed control part further comprises:
a second speed calculating part for calculating the speed of said motor in a second predetermined period on the basis of said output pulse of said encoder;
a second average speed calculating part for calculating said average speed using at least the current calculated speed, which is calculated by said second speed calculating part, and a calculated speed which has been m (m≧2) before; and
a second differentiating element which operates on the basis of a speed deviation of the output of said second average speed calculating part from said target speed.
10. A control unit for controlling a motor for use in a printer, as set forth in claim 1 , wherein said motor is a DC motor.
11. A method for controlling a motor for use in a printer, said method comprising the steps of:
detecting the speed of a motor for use in a printer in a predetermined period tv;
calculating an average speed using at least the current detected speed and a detected speed which has been detected n (≧2), which corresponds to substantially half period of the fluctuation in speed of said motor, before the timing in detecting said current detected speed; and
controlling the speed of said motor on the basis of a speed deviation of said average speed from a target speed of said motor.
12. A method for controlling a motor for use in a printer, as set forth in claim 11 , wherein assuming that the period of the fluctuation in speed of said motor is Tv, the number n used for calculating said average speed meets the following expression.
T v/(2t v)−2≦n<T v/(2t v)+2
13. A method for controlling a motor for use in a printer, as set forth in claim 12 , wherein said step of calculating said average speed calculates an average speed of k+1 detected speeds from the current detected speed to a detected speed of k (n>k≧0) before, and k+1 detected speeds from a detected speed of n before to a detected speed of k+1 before.
14. A method for controlling a motor for use in a printer, as set forth in claim 13 , wherein said step of controlling the speed of said motor controls the speed of said motor on the basis of the sum of said speed deviation and the output of a differentiating element which operates on the basis of said speed deviation.
15. A method for controlling a motor for use in a printer, as set forth in claim 14 , wherein said step of detecting the speed of said motor includes a step of calculating the speed of said motor in a period of an output pulse of an encoder, which generates said output pulse in accordance with the rotation of said motor, on the basis of said output pulse of said encoder.
16. A method for controlling a motor for use in a printer, as set forth in claim 15 , wherein said motor is a carriage motor for use in an ink jet printer.
17. A method for controlling a motor for use in a printer, as set forth in claim 11 , wherein said motor is a DC motor.
18. A computer-readable storage medium storing control program code for controlling a motor for use in a printer, comprising:
first program code means for detecting the speed of a motor for use in a printer in a predetermined period tv;
second program code means for calculating an average speed using at least the current detected speed and a detected speed which has been detected n (≧2), which corresponds to substantially half period of the fluctuation in speed of said motor, before the timing in detecting said current detected speed; and
third program code means for controlling the speed of said motor on the basis of a speed deviation of said average speed from a target speed of said motor.
Priority Applications (2)
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US10/253,498 US20030025471A1 (en) | 1999-07-26 | 2002-09-25 | Control unit and method for controlling motor for use in printer, and storage medium storing control program |
US11/074,761 US20050146300A1 (en) | 1999-07-26 | 2005-03-09 | Control unit and method for controlling motor for use in printer, and storage medium storing control program |
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JP2000141661A JP3859115B2 (en) | 1999-07-26 | 2000-05-15 | Printer motor control apparatus, control method, and recording medium recording control program |
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US09/625,994 US6528962B1 (en) | 1999-07-26 | 2000-07-26 | Control unit and method for controlling motor for use in printer, and storage medium storing control program |
US10/253,498 US20030025471A1 (en) | 1999-07-26 | 2002-09-25 | Control unit and method for controlling motor for use in printer, and storage medium storing control program |
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US11/074,761 Continuation US20050146300A1 (en) | 1999-07-26 | 2005-03-09 | Control unit and method for controlling motor for use in printer, and storage medium storing control program |
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US10/253,498 Abandoned US20030025471A1 (en) | 1999-07-26 | 2002-09-25 | Control unit and method for controlling motor for use in printer, and storage medium storing control program |
US11/074,761 Abandoned US20050146300A1 (en) | 1999-07-26 | 2005-03-09 | Control unit and method for controlling motor for use in printer, and storage medium storing control program |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070201843A1 (en) * | 2006-02-24 | 2007-08-30 | Omron Corporation | Electric motor controller |
US20100042262A1 (en) * | 2005-07-14 | 2010-02-18 | Access Business Group International Llc | Control methods for calibrating motor speed in an air treatment system |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3832712B2 (en) * | 2000-09-21 | 2006-10-11 | セイコーエプソン株式会社 | PRINT CONTROL DEVICE, CONTROL METHOD, AND RECORDING MEDIUM CONTAINING PRINT CONTROL PROGRAM |
US7026775B2 (en) * | 2001-12-20 | 2006-04-11 | Brother Kogyo Kabushiki Kaisha | Method and apparatus for controlling speed of moving body |
JP3687606B2 (en) * | 2001-12-20 | 2005-08-24 | ブラザー工業株式会社 | Motor control method and apparatus |
JP2004172854A (en) | 2002-11-19 | 2004-06-17 | Seiko Epson Corp | Image sensor controller, electronic apparatus and image sensor control method |
JP2004172861A (en) | 2002-11-19 | 2004-06-17 | Seiko Epson Corp | Electronic apparatus controller and method for controlling electronic apparatus |
JP2004170614A (en) | 2002-11-19 | 2004-06-17 | Seiko Epson Corp | Electronic equipment |
KR100777450B1 (en) | 2005-05-28 | 2007-11-21 | 삼성전자주식회사 | Encoder Speed Correction Method and System thereof |
JP4994768B2 (en) * | 2005-12-09 | 2012-08-08 | キヤノン株式会社 | Image forming apparatus |
JP2007182265A (en) * | 2005-12-29 | 2007-07-19 | Brother Ind Ltd | Sheet carrying device |
JP4483812B2 (en) | 2006-03-24 | 2010-06-16 | セイコーエプソン株式会社 | Printing apparatus, stick-slip handling method, program, and printing system |
US7898207B2 (en) * | 2007-12-04 | 2011-03-01 | Pitney Bowes Inc. | Method for controlling a DC motor |
JP5371419B2 (en) * | 2008-12-26 | 2013-12-18 | キヤノン株式会社 | Method for controlling motor in equipment |
JP5610838B2 (en) * | 2010-05-11 | 2014-10-22 | キヤノン株式会社 | Equipment with motor |
CN107718912A (en) * | 2017-11-21 | 2018-02-23 | 珠海冰河电子技术有限公司 | A kind of printer speed control method and device |
CN114337404B (en) * | 2021-12-30 | 2024-06-18 | 海信(广东)空调有限公司 | DC motor control method, air conditioner and computer readable storage medium |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4775945A (en) * | 1985-12-11 | 1988-10-04 | International Business Machines Corporation | Print head motor control system with automatic drive parameter calculations |
US5834912A (en) * | 1994-08-05 | 1998-11-10 | Kabushiki Kaisha Yashawa Denki | Motor speed control device |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3863118A (en) * | 1973-01-26 | 1975-01-28 | Warner Electric Brake & Clutch | Closed-loop speed control for step motors |
US4103216A (en) * | 1976-05-28 | 1978-07-25 | Tally Corporation | Stepping motor closed loop constant velocity control system |
US4490796A (en) * | 1981-10-16 | 1984-12-25 | International Business Machines Corporation | Print head motor control system using analog and digital feedback |
JPS60118077A (en) * | 1983-11-29 | 1985-06-25 | Oki Electric Ind Co Ltd | Spacing speed controlling method of printer |
JPH07115521B2 (en) * | 1988-11-30 | 1995-12-13 | 沖電気工業株式会社 | DC motor speed controller |
JP3230364B2 (en) * | 1994-03-03 | 2001-11-19 | 株式会社明電舎 | Speed estimation calculation processing method in speed control system |
JPH09202014A (en) * | 1996-01-24 | 1997-08-05 | Brother Ind Ltd | Printer |
EP0807528B1 (en) * | 1996-05-15 | 2001-12-12 | Océ-Technologies B.V. | Method and system for detecting the position of a carriage |
JP3281561B2 (en) * | 1996-12-25 | 2002-05-13 | シャープ株式会社 | Motor speed control device |
US6111384A (en) * | 1998-05-26 | 2000-08-29 | Eastman Kodak Company | Method for controlling motor speed |
-
2000
- 2000-05-15 JP JP2000141661A patent/JP3859115B2/en not_active Expired - Fee Related
- 2000-07-24 EP EP00306297A patent/EP1072425B1/en not_active Expired - Lifetime
- 2000-07-24 DE DE60026942T patent/DE60026942T2/en not_active Expired - Lifetime
- 2000-07-24 AT AT00306297T patent/ATE321669T1/en not_active IP Right Cessation
- 2000-07-26 CN CN00121956A patent/CN1120093C/en not_active Expired - Fee Related
- 2000-07-26 US US09/625,994 patent/US6528962B1/en not_active Expired - Lifetime
-
2002
- 2002-09-25 US US10/253,498 patent/US20030025471A1/en not_active Abandoned
-
2005
- 2005-03-09 US US11/074,761 patent/US20050146300A1/en not_active Abandoned
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4775945A (en) * | 1985-12-11 | 1988-10-04 | International Business Machines Corporation | Print head motor control system with automatic drive parameter calculations |
US5834912A (en) * | 1994-08-05 | 1998-11-10 | Kabushiki Kaisha Yashawa Denki | Motor speed control device |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20100042262A1 (en) * | 2005-07-14 | 2010-02-18 | Access Business Group International Llc | Control methods for calibrating motor speed in an air treatment system |
US20100037679A1 (en) * | 2005-07-14 | 2010-02-18 | Access Business Group International Llc | Control methods for setting a reference voltage in an air treatment system |
US8689603B2 (en) | 2005-07-14 | 2014-04-08 | Access Business Group International Llc | Control methods for setting a reference voltage in an air treatment system |
US9568210B2 (en) | 2005-07-14 | 2017-02-14 | Access Business Group International Llc | Control methods for setting a reference voltage in an air treatment system |
US10571394B2 (en) | 2005-07-14 | 2020-02-25 | Access Business Group International Llc | Control methods for setting a reference voltage in an air treatment system |
US20070201843A1 (en) * | 2006-02-24 | 2007-08-30 | Omron Corporation | Electric motor controller |
US7508150B2 (en) * | 2006-02-24 | 2009-03-24 | Omron Corporation | Electric motor controller |
Also Published As
Publication number | Publication date |
---|---|
US20050146300A1 (en) | 2005-07-07 |
CN1282015A (en) | 2001-01-31 |
DE60026942T2 (en) | 2006-08-24 |
JP2001103778A (en) | 2001-04-13 |
US6528962B1 (en) | 2003-03-04 |
EP1072425A2 (en) | 2001-01-31 |
JP3859115B2 (en) | 2006-12-20 |
EP1072425A3 (en) | 2001-02-07 |
DE60026942D1 (en) | 2006-05-18 |
EP1072425B1 (en) | 2006-03-29 |
CN1120093C (en) | 2003-09-03 |
ATE321669T1 (en) | 2006-04-15 |
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Legal Events
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Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |