JPH06198987A - Recording device - Google Patents

Abstract

PURPOSE:To reduce noise to be generated at the start of a motor by providing a control means for exciting a stepping motor in a stopped state such that supplying electric power increases during energization of a first excitation phase. CONSTITUTION:An MPU 1000 executes a control procedure of a predetermined program and controls all sections. The MPU 1000 comprises a ROM 1001 storing a program corresponding to the above, a RAM 1002 to be used as a work area at executing the control procedure, and a timer 1003 for measuring times. The MPU 1.000 controls a head cartridge (record head) 1, carrier motor 11, a conveying motor 13, and a recovery motor 26. The head cartridge 1 is driven by a discharge heater driver 1A and the carrier motor 11, the conveying motor 13 and the recovery motor 26 are respectively driven by motor drivers 11A, 13A, and 26A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording device.

[0002]

2. Description of the Related Art Conventionally, an operating unit (hereinafter referred to as a carrier) equipped with a recording head that reciprocates vertically with respect to a conveyance direction of a recording medium such as paper and OHP sheet (hereinafter also referred to as recording paper or simply paper). A so-called serial type recording apparatus (hereinafter referred to as a serial printer) having a) has been proposed in a form in which recording heads of various recording systems are mounted. The recording head used in this serial printer includes a wire dot system, a thermal system, a thermal transfer system, and an inkjet system.

[0003]

In these printers, the driving means for conveying the recording medium is the conveying roller, the pinch roller pressed by the conveying roller, and the gear for transmitting the power from the driving source to the conveying rotor. It is composed of rows and drive sources. A normal motor (mostly a stepping motor) is used as the drive source, and when the recording medium is started to be conveyed, the motor in a non-excited state is excited to perform so-called acceleration in which the speed is sequentially increased to a predetermined level. It is common to drive at a constant speed after accelerating to the transport speed of.

However, in many cases, a knob for manually feeding the recording medium is attached to the feeding roller,
The knob is turned to set the recording medium in the recording device before recording. In this case, when the knob rotates, the motor, which is the drive source, also rotates, so the rotor stop position of the motor is not constant, and even if recording is started and the motor is excited, the excited phase and the actual rotor stop If the phase does not match, the so-called step-out occurs in which the rotor cannot follow the excitation.

Therefore, usually, the first excitation time is lengthened, and after the rotor coincides with the excitation phase, the excitation phase is switched to control the motor to rotate (hereinafter, the first excitation time should be increased. Called hold).

However, the hold time depends on the load of the drive system and the structure of the motor, especially the rotor inertia, and it is necessary to set a time suitable for each drive system. Also, if the hold time is too long, the movement noise when the rotor moves because it matches the excitation phase,
This causes a rise in the noise level of the recording device.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems, for which purpose the present invention has a drive means for conveying a recording medium and a control means for controlling the drive means. By controlling the motor by the control means so as to reduce the noise generated when the motor, which is the drive source, is started, a low noise recording apparatus is obtained.

[0008]

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

(Embodiment 1) FIG. 1 is a diagram showing the construction of an ink jet recording apparatus according to the present invention. Here, 1 is a head cartridge having an ink jet recording head, 2
Is a carrier for mounting this and scanning in the X direction in the figure. Reference numeral 3 is a hook for attaching the head cartridge 1 to the carrier 2, and 4 is a lever for operating the hook 3. Reference numeral 5 is a support plate that supports an electrical connection portion for the head cartridge 1. Reference numeral 6 is an FPC (flexible printed circuit) for connecting the electrical connection portion and the main body control portion. Reference numeral 7 is a guide shaft for guiding the carrier 2 in the S direction, and is inserted into a bearing 8 of the carrier. Reference numeral 9 is a timing belt to which a carrier is mounted and which transmits power for moving the carrier in the X direction, and is stretched around pulleys 10A and 10B arranged on both sides of the device. The driving force is transmitted from the carrier motor 11 to one pulley 10B via a transmission mechanism such as a gear. Reference numeral 12 denotes a conveyance roller that regulates a recording surface of a recording medium such as paper and conveys the recording surface when recording or the like, and is driven by a conveyance motor 13. Further, a knob 29 for manually conveying the recording medium is attached to one end of the conveying roller 12. Reference numeral 14 denotes a paper pan for guiding the recording medium to the recording position, and 15 denotes a recording medium conveying roller 12 which is disposed in the feeding path of the recording medium.
It is a pinch roller that is pressed toward and conveyed. 16 is facing the discharge port of the head cartridge 1,
A platen for restricting the recording surface of the recording medium.
A paper discharge roller 17 is arranged downstream of the recording position in the recording medium conveyance direction and discharges the recording medium toward a paper discharge port (not shown). Reference numeral 18 denotes a spur provided corresponding to the paper discharge roller 17, and presses the paper discharge roller 17 via the recording medium to generate a conveyance force of the recording medium by the paper discharge roller 17. Reference numeral 19 is a release lever for releasing the bias of the pinch roller 15 and the spur 18 when setting the recording medium.

The platen 16 is rotatably supported on both sides by the shafts of the paper discharge rollers 17, and is urged from the stop position of the left and right plates 20 toward the front surface portion 21 of the paper pan 14 to make the conveying rollers 12 smaller than the outermost circumference. 16A provided at a plurality of positions in the portion 12A that is formed is the front portion 21 of the paper pan.
Touches the inside of.

Reference numeral 22 denotes a cap made of an elastic material such as rubber which corresponds to the ink ejection port forming surface of the recording head at the home position, and is supported so as to be able to come into contact with and separate from the recording head. The cap 22 is used for protection of the recording head during non-recording, and for ejection recovery processing of the recording head. The ejection recovery process is performed by causing the cap 22 to face the ejection port forming surface and driving an energy generating element provided in the ink ejection port and used for ejecting ink to eject ink from all ejection ports. A process (preliminary ejection) for removing ejection failure factors such as air bubbles and dust, or ink that has become thicker and is no longer suitable for recording, or the ink is ejected from the ejection port with the ejection port formation surface covered with a cap 22. Is a process for removing the cause of the ejection failure by forcibly discharging.

The cap 23 acts as a suction force for forcibly discharging the ink, and at the time of the discharge recovery process by the forcible discharge or the discharge recovery process by the preliminary discharge, the cap 22.
It is a pump used for sucking the ink received in. Reference numeral 24 is a waste ink tank for storing the waste ink sucked by the pump 23. The waste ink tank 24 is connected to the pump 23 by 28 tubes.

Reference numeral 25 denotes a blade for wiping the ejection port forming surface of the recording head. The blade 25 is located at a position where it projects toward the recording head side and performs wiping in the course of carrier movement, and a retracted position where it does not engage with the ejection port forming surface. It is movably supported. Reference numeral 26 is a motor, and 27 is a cam device for receiving power transmitted from the motor 26 to drive the pump 23 and move the cap 22 and the blade 25, respectively.

T is a temperature sensor provided to detect the temperature (environmental temperature) in the recording apparatus. The temperature sensor T is a known thermistor that shows an output voltage according to a temperature change, and an output signal is input to an MPU 1000 described later through a predetermined signal amplification circuit or the like.

FIG. 2 is a perspective view showing the recording medium conveying means in this embodiment.

As described above, in the carrying means for carrying the recording medium by pressing the pinch roller 15 against the carrying roller 12, the carrying roller 12 is connected to the carrying motor 13 through the gear train 30, and the carrying motor 13 is carried. By driving the motor 13 to rotate, the transport roller 12 can be rotated. In general, a stepping motor is often used as the carry motor, and when the recording medium is fed by a desired carry amount, the motor may be driven by the number of steps corresponding to the carry amount.

Further, a knob 29 for manually conveying the recording medium is attached to the conveying roller, which is used when the recording medium is set in the recording device. When the knob 29 is turned, not only the transport roller 12 but also the gear train 30 and the transport motor 13 connected to the transport roller rotate together.

Next, a stepping motor which is a drive source will be described with reference to FIGS. FIG. 3 is a sectional perspective view of a four-phase PM (permanent magnet) type stepping motor used as the carry motor 13 in this embodiment.

Reference numeral 41 is a shaft which is an output shaft of the motor, 42 is a magnet rotor integrally attached to the shaft 41, and the shaft 41 is a case 40A, 4A.
It is rotatably supported by bearings 43A and 43B provided at 0B.

Further, bobbins 4A and 44B wound with coils are arranged in the case 40B, and further, inside thereof,
Comb-shaped stators 45A, 45B, 45C and 45D are attached.

The stepping motor used in this embodiment is
One step is a 7.5 ° motor, and in this case, the rotor 42 is magnetized with 12 pole pairs of NS poles. Further, the stators 45A, 45B, 45C and 45D are shifted by 7.5 ° and are stacked in the axial direction. The coils wound around the bobbins 44A and 44B are two coils wound on one bobbin in different winding directions. The coil of 44A has one phase and three phases, and the coil of 44B has two coils.
Phases and 4 phases.

Next, the principle of motor rotation will be described with reference to FIG.

FIG. 4 shows the positional relationship between the stator magnetic poles and the rotor in the 2-2 phase excitation drive.

First, FIG. 4 (a) shows a case in which current is applied to the coil 1 phase of the bobbin 44A and the coil 2 phase of the bobbin 44B. At this time, the stator 45A is the N pole, and the following 45B is the S pole.
The poles, 45C are N poles, and 45D are S poles. Focusing on the south pole in this state, the center of the south pole is P in the figure.
1, P2, and the N pole of the rotor faces this.

Next, FIG. 4B shows the coil 2 in the (a) state.
It shows a state in which the current is switched from one phase of the bobbin 44A to a three-phase coil while the phases remain unchanged. Here, since the stator 45A changes to the S pole and 45B changes to the N pole, both the centers P1 and P2 of the S pole move by 7.5 °, and the N pole of the opposing rotor also moves by 7.5 °. .

Similarly, the center of the S pole can be moved by 7.5 ° by switching the phase of the coil for passing the current in FIGS. 4 (c) and 4 (d), and thus the rotor can be moved to 7.5. It becomes possible to move or rotate in increments of °.

Next, the first excitation of the motor will be described with reference to FIG.

FIG. 5A shows a so-called non-excitation state in which no current is supplied to the motor, and the stator is not magnetized.
This is the non-recording state, or the state when the recording medium is set in the recording device. As described above, the motor can be rotated by turning the knob, so the rotor 42
The position of is also not constant.

Next, in FIG. 5B, from the state shown in FIG. 5A, the magnetization of the stator is made to flow through the stator 1 shown in FIG. 4A, that is, the coil 1 phase of the bobbin 44A and the coil 2 phase of the bobbin 44B. 45A is the north pole, 45B is the south pole, and 45C
Is magnetized to the N pole and 45D is magnetized to the S pole. Now, the centers of the stator south poles are P1 and P2 in the figure, and the center of the north pole of the rotor that should be opposed to this is at Q. Since the N pole and the S pole attract each other, Q moves toward P1 (in the direction of the arrow in the figure), and the rotor stops at the position where Q and P1 coincide. This state is the state shown in FIG. As described above, the motor rotates by switching the phase of the coil that allows current to flow. However, when the first excitation is performed from the non-excitation state as shown in FIG. 5, the excitation is performed when the rotor and stator phases do not match. When the phases are switched, the rotor cannot follow the phase switching of the stator, and so-called step-out occurs in which the rotation of the motor is stopped.

Further, FIG. 6 shows the same as FIG.
It is a graph showing the movement of the rotor when the rotor starts to hold the state and moves so as to match the phase of the stator. The horizontal axis represents the elapsed time from the start of holding, the vertical axis represents the phase position of the stator, and shows the locus of movement of the N pole center Q of the rotor. In this way, the hold is started, and the rotor north pole center Q becomes the stator south pole center P1.
In the case of moving toward P1, it is coincident with P1 but cannot be stopped immediately, and once it goes too far (overshoot) and approaches again, it ends up stopping at the position of P1 while vibrating.

Therefore, the phase switching of the stator is performed after t1 time when the phases of the rotor and the stator are completely coincident with each other and stopped after the vibration is converged. This is a method for surely starting the motor without causing step-out. is there.

Next, the relationship between the rotor position and the input current to the coil will be described.

FIG. 7 shows from the start of holding until the switching to the next phase is performed. FIG. 7 (a) shows the position of the rotor and FIG. 7 (b) shows the input current waveform. When the current I is input and the hold is started at time 0, the rotor Q (FIG. 5B) approaches the stator P1 while vibrating, and the vibration converges at time t1. However, if the hold is not completed at the time t1, the hold is executed until the time t2 with some margin, and then the phase of the coil is switched at the time t2 and the coil is energized until the time t3, the Q of the rotor moves to the stator P2. start. Here, as described above, since the position of the rotor in the non-excited state is not constant, the rotor position Q (FIG. 5) at the moment the hold is started is also arbitrary,
The distance to the destination P1 also varies depending on the rotor position Q. Therefore, when the hold time is long, the vibration increases due to the rotor position Q, and appears as noise. Further, the stepping motor has a starting frequency, and if the frequency is within this self-starting frequency, the stepping motor can rotate without stepping out even if excitation is performed without acceleration.

In this case, even if the vibration at the rotor position Q (FIG. 5) is not completely converged, even if the phase is switched to the next phase, the motor rotates without step-out. Therefore, there is no problem even if the hold time is short. However, when driving at a frequency higher than the self-starting frequency and acceleration is required, the hold time must be lengthened.

Next, the input current waveform according to the present invention will be described.

FIG. 8 represents the input current waveform implemented by the present invention. As described above, when the hold is started, a force for pulling the rotor into the stator is generated. Although this force is constant, the initial position Q of the rotor varies,
Depending on the position Q of the rotor, the speed at which the stator moves to the position P1 (FIG. 5) varies, and noise may appear due to the difference in vibration. Therefore, as shown in FIG. 8, by gradually increasing the input current to the coil from the moment when the hold is started, the force of pulling in the rotor of the stator is gradually increased, and the rotor does not move rapidly. Control to gradually increase the speed.

By controlling in this way, the movement of the rotor initial position Q does not start suddenly,
This reduces vibration and even noise.

In this embodiment, the input current waveform is the waveform obtained by using the trigonometric function sin curve, but the present invention is not limited to this, and the force of pulling in the rotor of the stator is gradually increased. It is sufficient if the waveform changes to.

FIG. 9 is a block diagram showing a configuration example of the control system of the recording apparatus in the configuration described so far.
In the figure, reference numeral 1000 denotes an MPU (microprocessor) that executes a control procedure of a preset program or the like to control each unit, a ROM 1001 storing a program or the like corresponding to the control means, and a work for executing the control procedure. RAM 1002 used as an area
And a one-chip type MPU that incorporates a timer 1003 that measures time for execution of control.

Of the configuration of FIG. 1 described above, the MPU 100
Controlled by 0 is a head cartridge (recording head) 1, a carrier motor 11, a conveyance motor 13 and a recovery system motor 26. The head cartridge 1 is driven by an ejection heater driver 1A, and the carrier motor 11 and the conveyance motor 13 are driven. The recovery system motor 26 is driven by the motor drivers 11A, 13A, 26A, respectively. Further, the MPU 1000 recognizes the cap position and the movement position of the carrier 2 based on the detection of the recovery system home sensor 35 and the carrier home sensor 36.

Next, FIG. 10 is a diagram showing an example of the control structure of the carry motor driver 13A in FIG.
In the figure, signal lines 1101 to 1104 are excitation signal lines for instructing the driver 1108 to flow current to the winding coils 1 to 4 phases of the carry motor 13, and are controlled by the MPU 1000. Further, the power supply of the carry motor 13 is supplied from the power supply line 1106 through the transistor switch 1107, and the transistor switch 1107 is the MPU.
It is turned on / off according to the signal of the signal line 1105 controlled by 1000.

Next, based on the configurations of FIGS. 9 and 10, FIG.
Control for gradually increasing the input current to the coil from the moment when the hold as shown in (4) is started will be described with reference to the flowchart of FIG.

First, FIG. 11A shows a desired current waveform at the time of holding in which the horizontal axis represents time t and the vertical axis represents current i. The hold current takes the maximum value I at T _100. sin curve, i = I sin (πt / 2T
₁₀₀ ). The _{T 1, T 2, T 3} ... is, the T ₁₀₀ 1
The time is divided into 00 and choreographed sequentially. Here, 100 pieces of data t ₁ , t ₂ , t _{3 obtained} by calculating the current-carrying time per each time from the current area per each time ...
Is stored in the ROM 1001 as a table. Formula here t _{n is, t n = (T n -T} n-1) ∫sin (π
t / 2T ₁₀₀ ). FIG. 11B shows FIG.
Current conduction time t ₁ , t ₂ , t ₃ ... And T ₁ , T
_2, T ₃ ... is a diagram showing the relationship between.

Next, the flowchart of FIG. 12 will be described.

First, in a non-recording state such as when the power is turned on, s
The carry motor is initialized as in step 1. That is, the signal line 1105 in FIG.
3 is stopped, and the excitation signal line 1101
˜1104 are turned off and the carry motor 13 is kept in a non-excited state. Then, in step 2, the hold line having a waveform as shown in FIG. 11A is supplied from the step 2 to the signal line 1105 so that the motor power can be supplied to the carry motor 13. Then, in step 3, the value of the counter n provided on the RAM 1002 is set to 1. Next, at step 4, timer 1
003 is cleared, and at step 5, the signal line 1101,
When 1102 is turned on, current is passed through the 1-phase and 2-phase of the carry motor 13. Then, at step 6, the timer 1003 is started, and at step 7, it is determined whether the value of the timer 1103 matches the t _n time, and step 7 is repeated until they match, and if they match, the process proceeds to step 8 and the signal lines 1101, 11
02 is turned off to stop the flow of current to the 1-phase and 2-phase of the carry motor 13. Then, at step 9, the timer 1103
Values wait until it coincides with (T _100/100) Time, 1 is added if match step10 the value of the counter n, s
In step 11, it is judged whether or not the value of the counter n exceeds 100, and if not, the process returns to step 4. Also, st
If it exceeds 100 in ep11, the process proceeds to step12, a current is supplied to the first phase and the second phase of the carry motor 13, and the hold process is ended in step13.

Although the ink jet recording apparatus has been described in the present embodiment, the present invention is not limited to this, and can be applied to a conveyance drive system of various recording systems such as a thermal transfer recording apparatus and a sublimation type recording apparatus. Further, the present invention is not limited to the transport drive system, and can be applied to any drive system having a motor as a drive source, such as a carrier drive carrier motor and a recovery system drive recovery system motor.

Although the PM type stepping motor has been described in the present embodiment, the present invention is not limited to this, and the same applies to an HB (hybrid) type stepping motor and a VR (variable reluctance) type stepping motor. Can be applied to.

(Embodiment 2) In the above embodiment, the excitation signal lines 1101 to 1104 are controlled to control the hold current, but the power supply control line 1105 may be controlled to obtain the hold current as shown in FIG. It is possible. The method will be described with reference to the flowchart of FIG.

The operation of step1 is the same as that of step1 in FIG. Then, the transport motor 13 starts from step 2A.
In the step 2A, the signal lines 1101 and 1102 are turned on by a procedure of passing a hold current having a waveform as shown in FIG.
Then, the driver 1108 is controlled so that current can be passed through the 1-phase and 2-phase of the carry motor 13. Next, move to step 3,
The value of the counter n provided on the RAM 1002 is set to 1. Then, at step 4, the timer 1003 is cleared, and at step 5A, the signal line 1105 is turned on to supply the motor power to the carry motor 13. Then the transport motor 1
Current starts to flow in the 1-phase and 2-phase of 3. Then, the timer 1003 is started at step 6, and the timer 1 is started at step 7.
It is determined whether the value of 103 matches the time t _n, and step 7 is repeated until they match, and if they match, the process proceeds to step 8A to turn off the signal line 1105 and stop the power supply to the carry motor 13. Then, at step 9, timer 110
Wait until the value of 3 matches (T _100/100 ) hours,
If they match, 1 is added to the value of the counter n in step 10,
In step 11, it is judged whether or not the value of the counter n exceeds 100, and if not, the process returns to step 4. Also,
If the number exceeds 100 in step 11, the process proceeds to step 12A to supply power to the carry motor 13,
The hold process ends with.

(Embodiment 3) In this embodiment, the carry motor 1 is used.
As shown in FIG. 14, the motor power supply 2 has a power supply system for supplying power to the motor 3, and the motor power supply 2 is set to have a lower voltage than the motor power supply 1. When the control shown in the flowchart of FIG. 13 is performed with the configuration shown in FIG. 14, a current waveform obtained by superimposing the current from the motor power supply 1 and the current from the motor power supply 2 as shown in FIG. 15 is obtained. That is, even if the supply of the motor power supply 1 is stopped at step 8 in the carry motor 13, the exciting current is lightly flowed by the motor power supply 2. Therefore, the unstable state of the non-excitation state is eliminated and the vibration of the motor is effectively converged. be able to.

(Embodiment 4) Next, a control method of controlling the voltage of the power supply of the carry motor 13 to gradually increase the voltage applied to the carry motor 13 during hold will be described.

First, FIG. 16 is a configuration diagram for controlling the voltage applied to the carry motor according to an instruction from the MPU 1000. The D / A converter 1700 receiving the instruction from the MPU 1000 through the signal line 1703, the voltage V
_{DA is applied} to the operational amplifier 1701, and the operational amplifier 1701 applies the base current of the transistor 1702 to the resistor R so that the motor voltage V _M becomes V _M * R2 / (R1 + R2) = V _DA.
It works like flowing to 3. As described above, MPU1000
Can generate any voltage as the motor voltage.

Next, a method of controlling the hold voltage of the carry motor using the above configuration will be described with reference to FIGS. FIG. 17 is a plot of a desired voltage waveform (solid line) at the time of holding with the time t on the horizontal axis and the voltage v on the vertical axis, and a sin curve in which the hold voltage takes the maximum value V ₁₀₀ at T ₁₀₀ , that is, , V = V ₁₀₀ sin (πt / 2T ₁₀₀ ). Further, T ₁ , T ₂ , T _3, ... Are times when T ₁₀₀ is divided into 100 and choreographed sequentially. Here, the average voltage for each time is calculated, and the 100 pieces of data V ₁ , V ₂ ,
Stored as table V ₃ ... to ROM1001. The double-lined graph in the figure shows the voltage applied to the carry motor by this control.

Next, the flowchart of FIG. 18 will be described. s
The operation of step1 is the same as that of step1 of FIG. Then, in step 2A, the signal lines 1101 and 1102 are turned on.
Then, the driver 1108 is controlled so that current can be passed through the 1-phase and 2-phase of the carry motor 13. Next, move to step 3,
The value of the counter n provided on the RAM 1002 is set to 1. Then, in step 4, the timer 1003 is cleared, and in step 5B, the DA converter 1700 is instructed via the signal line 1703 so that the motor voltage becomes V _N. Then, the voltage V _N is applied to the first phase and the second phase of the carry motor 13, and the current corresponding to the voltage starts to flow. And step6
In the timer is started 1003 waits until the value of the timer 1103 in step9 matches (T _100/100) Time, consistent by adding 1 to the value of the counter n at step10 if the value of the counter n at step11 100 It is judged whether or not it has exceeded, and if not, the process returns to step 4.
Also, if it exceeds 100 in step 11, step 1
Then, the process proceeds to 3 and the hold process ends.

(Fifth Embodiment) In the first to fourth embodiments, the electric power supplied to the motor is controlled to be gradually increased. However, the present invention is not limited to this and has, for example, two power supply systems. In the configuration of FIG. 14, a low voltage (v ₀ ; FIG. 19) is applied in the first phase excitation, and the voltage is switched to a high voltage (v ₁ ; FIG. 19) at time t1 before the time t2 when phase switching is performed. Can be similarly applied.

Further, although the voltage is switched in two steps in FIG. 19, it may be switched in three steps or more.

(Embodiment 6) In each of the above embodiments,
Although the power supply to the first excitation phase to the stepping motor is changed so as to be increased, the present invention is not limited to this and is similarly applied to energization to the phase after switching from the first excitation phase. can do.

When the stepping motor is driven by the 2-2 phase excitation, only the first excitation may be energized by the 1 phase excitation, and then the 2 step excitation may be performed. For example, FIG. 20A shows a so-called one-phase excitation state in which a current is applied only to one phase of the coil of the bobbin 44A, and the bobbin 44A is energized at the low voltage v ₀ in the fifth embodiment. At the time of switching from this state to the next phase, switching to two-phase excitation with a high voltage v ₁ is performed. This state is shown by the coil 1 phase of the bobbin 44A and the bobbin 44 of FIG. 20 (b).
This is the case where a current is applied to the two phases of the B coil.

FIG. 21 shows current waveforms when switching from such one-phase excitation to two-phase excitation. Figure 2
1, a small current i due to a low voltage v _{0 at} time t1
The 1-phase excitation of ₀ is completed, and the 2-phase excitation is started at the same time, and the supply current to the excitation phase is changed at a high voltage v ₁ .

By performing such control, it is possible to reduce the vibration of the rotor of the stepping motor when the one-phase excitation is switched to the two-phase excitation.

(Embodiment 7) In Embodiments 1 to 4, the current or voltage applied to the motor was controlled so as to form a sin curve, but the present invention is not limited to this, and may be linear, for example. Increase or 1- (1 / e
It can be applied using various increasing functions such as ^t ). In this case, the same effect can be obtained by using a function suitable for each drive system.

Further, in each of the above embodiments, the current or voltage to be applied to the motor is stored as a table in the ROM for control, but the present invention is not limited to this, and control is performed while sequentially calculating. May be. In this case, the memory capacity can be saved.

Further, in each of the above embodiments, the motor is controlled by one fixed pattern, but a plurality of control patterns are prepared, and the optimum control is made each time according to the use conditions (for example, the peripheral temperature of the recording apparatus). With the control pattern,
More reliable control is possible.

[0064]

As described above, according to the present invention, by controlling the drive system using the motor as the drive source, it is possible to reliably drive the motor and obtain a low noise recording apparatus.

[Brief description of drawings]

FIG. 1 is a perspective view showing an inkjet recording apparatus equipped with a disposable head to which the present invention is applied.

FIG. 2 is a perspective view showing a recording medium conveying unit of the inkjet recording apparatus to which the present invention is applied.

FIG. 3 is a perspective view showing a structure of a stepping motor which is a carrier driving source of a recording apparatus to which the present invention is applied.

FIG. 4 is an explanatory diagram showing a positional relationship between a stator and a rotor of a stepping motor.

FIG. 5 is an explanatory diagram showing a positional relationship between a stator and a rotor of a stepping motor.

FIG. 6 is a graph illustrating rotation of a rotor of a stepping motor.

FIG. 7 is an explanatory diagram showing the relationship between the rotation of the rotor of the stepping motor and the waveform of the input current to the motor.

FIG. 8 is an explanatory diagram showing an input current waveform to a motor to which the present invention is applied.

FIG. 9 is a block diagram of a recording apparatus to which the present invention is applied.

FIG. 10 is a motor drive circuit diagram of a recording apparatus to which the present invention is applied.

FIG. 11 is an explanatory diagram showing an input current waveform to the motor to which the present invention is applied.

FIG. 12 is a flowchart showing a control procedure of the recording apparatus to which the present invention is applied.

FIG. 13 is a flowchart showing another control procedure of the recording apparatus to which the present invention is applied.

FIG. 14 is another motor drive circuit diagram of the recording apparatus to which the present invention is applied.

FIG. 15 is an explanatory diagram showing a waveform of an input current to a motor according to another control method of the present invention.

FIG. 16 is another motor drive circuit diagram of the recording apparatus to which the present invention is applied.

FIG. 17 is an explanatory diagram showing a waveform of an input voltage to a motor according to another control method of the present invention.

FIG. 18 is a flowchart showing another control procedure of the recording apparatus to which the present invention is applied.

FIG. 19 is an explanatory diagram showing a waveform of an input voltage to a motor according to another control method of the present invention.

FIG. 20 is an explanatory diagram showing a positional relationship between a stator and a rotor of a stepping motor.

FIG. 21 is an explanatory diagram showing a waveform of an input current to a motor according to another control method of the present invention.

[Explanation of symbols]

 1 Head Cartridge 2 Carrier 7 Guide Shaft 8 Timing Belt 11 Carrier Motor 12 Conveyor Rotor 13 Conveyor Motor 14 Paper Pan 17 Paper Ejection Roller 18 Spur 36 Carrier Home Sensor 1000 MPU 1001 ROM 1002 RAM 1003 Timer

Claims (6)

[Claims] 1. A recording apparatus having a drive means using a stepping motor as a drive source and a control means for controlling the drive means, wherein the control means applies a first excitation phase to the stepping motor in a stopped state. A recording apparatus, which excites so as to increase power supply during an energization period. 2. The recording apparatus according to claim 1, wherein the control means increases the electric power supplied to the longest excitation phase when starting the movement of the stepping motor. 3. The recording apparatus according to claim 1, wherein the control means supplies a current to the stepping motor by repeating on / off of an excitation phase. 4. The recording apparatus according to claim 1, wherein the control unit supplies a current to the stepping motor by repeatedly turning on and off a power source. 5. A plurality of power supply sources for the stepping motor are provided, and the control means controls the current supply to the stepping motor by repeating ON / OFF of one of the power supply sources. The recording apparatus according to claim 1, wherein the recording apparatus is a recording apparatus. 6. The recording apparatus according to claim 1, wherein the control unit supplies a current to the stepping motor by changing a voltage of a power source.