JP2001341297A - Liquid jet unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid jet unit having a head member for ejecting a liquid from nozzle openings in which micro vibration control can be carried out in correspondence with the arranging position of nozzle openings. SOLUTION: The inventive liquid ejector comprises a head member 8 having a plurality of nozzle openings 51 sorted into a plurality of groups based on the arranging position, a common reservoir 49 for storing liquid, and liquid channels 48, 46, 36, 47, 50 for supplying liquid from the common reservoir 49 to the plurality of nozzle openings 51. Micro vibration control signal generating means 6, 12, 55-58, 200 generate micro vibration control signals for respective sorted groups of nozzle openings 51. The micro vibration control means 6 drives a micro vibration means 35 for each sorted group of nozzle openings 51.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid ejecting apparatus having a head member for ejecting liquid from a nozzle opening, for example, an ink jet recording apparatus having a recording head for ejecting ink droplets from a nozzle opening to perform recording. More particularly, the present invention relates to a liquid ejecting apparatus that prevents a liquid from being thickened at a nozzle opening.

[0002]

2. Description of the Related Art An ink jet recording apparatus such as an ink jet printer or an ink jet plotter moves a recording head in a main scanning direction and also moves a recording paper (a kind of printing recording medium) in a sub scanning direction. By ejecting ink droplets from the nozzle openings of the recording head in conjunction with this movement, an image (character) is recorded on recording paper. The ejection of the ink droplets is performed, for example, by expanding and contracting a pressure generating chamber communicating with the nozzle opening.

At the nozzle opening of the recording head, the ink is exposed to air, so that the ink solvent (eg, water) evaporates gradually. Due to the evaporation of the ink solvent, the viscosity of the ink at the nozzle opening increases, deteriorating the image quality of the recorded image. That is, when the ink viscosity of the portion increases, the ejected ink droplets may fly in a direction deviated from the normal direction.

For this reason, in the ink jet recording apparatus, measures have been taken to prevent the viscosity of the ink at the nozzle opening from increasing. One of the measures to increase the viscosity is agitation of the ink due to the slight vibration of the meniscus. Here, the meniscus is a free surface of the ink exposed at the nozzle opening.

[0005] In the stirring of the ink, the meniscus is alternately moved in the ejection direction of the ink droplet and the drawing direction opposite to the ejection direction so that the ink droplet is not ejected. This movement of the meniscus also causes the pressure generating chamber to expand and
It is performed by contracting. By finely vibrating the meniscus, the ink at the nozzle opening is agitated, thereby preventing the ink from increasing in viscosity.

[0006] The stirring of the ink is performed in conjunction with the recording operation. For example, during the acceleration period immediately after the main scanning of the carriage on which the recording head is mounted (ie, outside of printing)
Or during the recording period of one line (that is, during printing). In the stirring during the acceleration period, a non-printing micro-vibration drive signal (micro-vibration control signal) for micro-vibrating the meniscus is supplied to the recording head, and the meniscus of all the nozzle openings is micro-vibrated. In addition, during stirring during printing, a micro-vibration pulse is generated from a discharge drive signal for discharging ink droplets, and the generated micro-vibration pulse is supplied to the recording head. Thus, the ink is stirred at the nozzle openings that do not discharge ink droplets.

In Japanese Patent Application No. 2000-21507,
The document describes that the meniscus of the ink at the nozzle opening is finely vibrated from an appropriate timing immediately before ejecting the ink droplet to a predetermined time or an appropriate timing immediately before ejecting the ink droplet.

[0008]

In the conventional ink jet recording apparatus, the non-printing minute vibration driving signal supplied to the recording head is supplied to all the nozzle openings regardless of the arrangement position of the nozzle openings. For this reason, there is a possibility that adverse effects such as wetting around the nozzle openings may occur due to the “rebound” of the pressure fluctuation of the reservoir due to the micro-vibration caused by the non-printing micro-vibration drive signal.

In order to improve the pressure fluctuation absorbing ability of the reservoir, it has been proposed to partition a part of the reservoir communicating with the nozzle opening by a thin portion (Japanese Patent Laid-Open No. 9-3).
No. 14836). However, even in this case, if the compliance of the thin portion is small, the pressure fluctuation in the reservoir cannot be sufficiently absorbed. In this case, there is also a possibility that wetting occurs around the nozzle opening.

The present invention has been made in view of the above points, and provides an ink jet recording apparatus capable of performing micro-vibration control corresponding to the arrangement position of a nozzle opening. It is an object of the present invention to provide a liquid ejecting apparatus having a head member for ejecting liquid from a nozzle opening, capable of performing micro-vibration control corresponding to an arrangement position of the nozzle opening.

[0011]

SUMMARY OF THE INVENTION The present invention provides a plurality of nozzle openings, each of which is divided into a plurality of groups based on the arrangement position, a common reservoir for storing liquid, and a plurality of nozzle openings from the common reservoir. A head member having a liquid flow path for supplying liquid to the nozzle, fine vibration means for finely vibrating the liquid in the nozzle opening portion for each group of separated nozzle openings, and a fine vibration means for each group of separated nozzle openings. Micro vibration control signal generating means for generating a micro vibration control signal, and micro vibration control means for driving the micro vibration means based on the micro vibration control signal,
A liquid ejecting apparatus comprising:

According to the present invention, the fine vibration control signal generating means generates a fine vibration control signal for each group of the nozzle openings classified based on the arrangement position, and based on the fine vibration control signal. Is driven, suitable microvibration control according to the pressure fluctuation absorbing ability of the common reservoir can be realized.

Preferably, the common reservoir is at least partially defined by a thin portion. In this case, the pressure fluctuation absorbing ability of the common reservoir is improved.

The plurality of nozzle openings are usually arranged in a row. In this case, preferably, adjacent nozzle openings are separated into different groups. By providing, for example, a time difference in the micro-vibration control of the adjacent nozzle openings, even when the pressure fluctuation absorbing ability of the common reservoir is small, it is possible to more effectively prevent the area around the nozzle openings from getting wet.

For example, a plurality of nozzle openings are classified into n groups at intervals of n, and, for example, a time difference can be provided in the micro-vibration control for each group. As a more specific example, the plurality of nozzle openings may be divided into two groups alternately (every two) and the microvibration control of each group may be performed alternately (with a time difference).

Preferably, each vibration control signal generated for each group of the separated nozzle openings has a continuous pulse waveform, and the pulse waveform of each vibration control signal is substantially the same. The appearance frequency of the pulse waveform of each fine control signal is substantially the same, and the appearance cycle of the pulse waveform of each fine control signal is shifted for each fine control signal. The deviation of the appearance period of the pulse waveform provides the time difference of the micro vibration control.

Further, the micro-vibration control signal generating means includes a micro-vibration signal generating means for generating a common micro-vibration signal, and a micro-vibration mode signal generating means for generating a micro-vibration mode signal for each of the separated groups of nozzle openings. A signal fusion unit that generates a vibration control signal based on the common vibration signal and the vibration mode signal,
May be provided.

In this case, it is preferable that the signal fusion unit generates a fine vibration control signal by ANDing the common fine vibration signal and the fine vibration mode signal.

In this case, for example, the common fine vibration signal is a periodic signal having a predetermined waveform, and the fine vibration mode signal has a predetermined rectangular pulse train and has the same period as the common fine vibration signal. It is a periodic signal having.

The liquid is, for example, ink, and the head member is, for example, a recording head.

Further, a fine vibration control signal generating means for generating a fine vibration control signal for each of the separated groups of nozzle openings, and a fine vibration control means for driving the fine vibration means based on the fine vibration control signal. , Can be implemented by a computer system.

A program for realizing each means in the computer system and a computer-readable recording medium on which the program is recorded are also covered by the present invention.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the ink jet recording apparatus according to the first embodiment of the present invention is an ink jet printer, and includes a printer controller 1 and a print engine 2.

The printer controller 1 includes an external interface (external I / F) 3, a RAM 4 for temporarily storing various data, and a ROM for storing control programs and the like.
5, a control unit 6 including a CPU and the like, an oscillation circuit 7 for generating a clock signal, a drive signal generation unit 9 for generating a drive signal to be supplied to the recording head 8, a drive signal, Internal interface (internal I / F) 10 for transmitting dot pattern data (bitmap data) developed based on print data to the print engine 2
And

The external I / F 3 receives print data composed of, for example, a character code, a graphic function, and image data from a host computer (not shown). Also, a busy signal (BUSY) and an acknowledgment signal (ACK) are output to a host computer or the like via the external I / F3.

The RAM 4 has a reception buffer 4A, an intermediate buffer 4B, an output buffer 4C, and a work memory (not shown). The receiving buffer 4A temporarily stores the print data received via the external I / F 3, the intermediate buffer 4B stores the intermediate code data converted by the control unit 6, and the output buffer 4C The dot pattern data is stored. Here, the dot pattern data is print data obtained by decoding (translating) intermediate code data (for example, gradation data).

The ROM 5 stores font data, graphic functions, and the like, in addition to a control program (control routine) for performing various data processing.

The control unit 6 performs various controls according to a control program stored in the ROM 5. For example, the print data in the reception buffer 4A is read, and the print data is converted into intermediate code data, and the intermediate code data is stored in the intermediate buffer 4B. The control unit 6
Analyzes the intermediate code data read from the intermediate buffer 4B and develops (decodes) it into dot pattern data with reference to the font data and graphic functions stored in the ROM 5. After performing the necessary decoration processing, the control unit 6 stores the dot pattern data in the output buffer 4C.

If one recordable dot pattern data is obtained by one main scan of the recording head 8,
The dot pattern data for one line is stored in the output buffer 4.
C sequentially output to the recording head 8 through the internal I / F 10. When one line of dot pattern data is output from the output buffer 4C, the expanded intermediate code data is erased from the intermediate buffer 4B, and expansion processing for the next intermediate code data is performed.

The drive signal generator 9 according to the present embodiment outputs an ejection drive signal (a fine vibration control signal in printing) used for fine vibration of the meniscus 52 (see FIG. 5B) during recording and printing. Main signal generating unit 11 for generating a non-printing common micro-vibration signal used for micro-vibration of the non-printing meniscus 52 (see FIG. 5B). The ejection drive signal from the main signal generation unit 11 and the non-printing common micro-vibration signal from the micro-vibration signal generation unit 12 are input, and the ejection driving signal or the non-printing common micro-vibration signal is input to the internal I
/ F10, and a selection unit 13 for outputting to the / F10.

As shown in FIG. 2, for example, the ejection driving signal has a waveform 61t having a waveform 61t which rises from the reference voltage by a predetermined voltage, then temporarily drops below the reference voltage, rises again to the predetermined voltage, and falls again below the reference voltage. One waveform part 61,
Trapezoidal waveform 6 that drops by a predetermined voltage from the reference voltage 6
A second corrugated portion 62 having 2t and a third having a trapezoidal waveform 63t similar to the trapezoidal waveform 62t of the second corrugated portion 62
A periodic signal in which a waveform portion 63 and a fourth waveform portion 64 having a waveform 64t having a voltage substantially the same as the lowest voltage of the first waveform portion 61 and then returning a predetermined voltage above the reference voltage and then returning are connected in series. It is constituted by.

On the other hand, the non-printing common micro-vibration signal is usually constituted by the same signal. For example, as shown in FIG.
It is composed of a periodic signal in which trapezoidal pulses 201 whose potential is switched between a minimum potential and a maximum potential are connected in series at substantially equal intervals.

The drive signal generator 9 can be constituted by a logic circuit, and can be a CPU, ROM, R
It can also be configured by a control circuit configured by an AM or the like.

The print engine 2 includes a paper feed mechanism 16
, A carriage mechanism 17 and the recording head 8.

The paper feed mechanism 16 is composed of a paper feed motor, a paper feed roller, and the like. As shown in FIG.
The recording paper 18 (a type of print recording medium) is sequentially sent out in conjunction with the recording operation of the recording head 8. That is, the paper feed mechanism 16 moves the recording paper 18 in the recording paper feed direction which is the sub-scanning direction.

As shown in FIGS. 4A to 4C, the carriage mechanism 17 is movably mounted on a guide member 20 and can carry the recording head 8 and the ink cartridge 19, and a drive pulley. 22 and the driven pulley 23 and the carriage 2
1 and a pulse motor 25 for rotating the drive pulley 22, a printer housing 26 in a state parallel to the recording paper width direction (along the main scanning direction).
A linear encoder 27 installed on the carriage 21
And a slit detector 29 attached to the linear encoder 27 and capable of detecting a plurality of slits 28 of the linear encoder 27.

The linear encoder 27 of this embodiment is
It is a transparent thin plate member, and the slits 28 are formed at a pitch of 360 dpi as shown in FIG.
The slit detector 29 can be configured by, for example, a photo interrupter.

According to such a carriage mechanism 17,
The operation of the pulse motor 25 causes the carriage 21 to reciprocate along the width direction (main scanning direction) of the recording paper 18. Accordingly, the recording head 8 mounted on the carriage 21 moves along the main scanning direction. The movement of the carriage 21 is performed starting from the reference position on the home position side. Here, the home position is a position where the carriage 21 is made to stand by when the power is not turned on or when recording is not performed for a long time. In the present embodiment, a home position is provided at the right end in FIG.

The recording head 8 is located at the home position.
Is provided with a capping mechanism 30 for preventing the evaporation of the ink solvent in the nozzle openings 51 (described later).

On the other hand, the reference position is set at a position slightly to the left of the home position. Specifically, a reference position is set between the right edge of the recording paper 18 and the capping mechanism 30.

When the carriage 21 moves, the slit detector 29 moves together with the carriage 21. With this movement, the slit detector 29
Are sequentially detected, and a pulse-like detection signal corresponding to the pitch of the slits 28 is output. The control unit 6 recognizes the position of the recording head 8 based on the detection signal from the slit detector 29.

Specifically, the control unit 6 controls the carriage 21
Resets the count value of the position counter in a state where is positioned at the reference position, receives a rising pulse (detection signal) from the slit detector 29 output with the movement of the carriage 21, and sets the position every time a pulse is received. Count up the counter. Thus, the count value of the position counter becomes head position information indicating the position of the carriage 21, that is, the scanning position of the recording head 8. Here, the position counter may be provided, for example, in a work memory (not shown) of the RAM 4, but the counter may be provided separately.

Accordingly, the linear encoder 27 and the slit detector 29 function as scanning position information output means, that is, information (detection signal) relating to the position of the recording head 8 with the main scanning of the carriage 21 (recording head 8). Is output. The control unit 6 and the position counter (R
AM4) functions as a scanning position holding unit, that is, holds the updated count value after updating the count value (head position information) of the position counter based on the detection signal from the slit detector 29.

Next, the recording head will be described. The illustrated recording head 8 is schematically constituted by an actuator unit 33 and a flow path unit 34 as shown in FIG. The illustrated recording head 8 uses the piezoelectric vibrator 35 in the flexural vibration mode as a pressure generating element.

Here, the piezoelectric vibrator 3 in the flexural vibration mode
Reference numeral 5 denotes a structure in which the pressure generating chamber 36 is contracted by the charging to deform the pressure generating chamber 36 so as to reduce the volume, and is expanded by the discharge to deform the pressure generating chamber 36 so as to increase the volume.

The actuator unit 33 includes a first lid member 37, a spacer member 38, a second lid member 39, a piezoelectric vibrator 35, and the like. Channel unit 34
Are the ink supply port forming substrate 40 and the reservoir forming substrate 41
And a nozzle plate 42 and the like. The recording head 8 is configured by integrating the actuator unit 33 and the flow path unit 34 with the adhesive layer 43. Note that the adhesive layer 43 can be composed of a heat-sealing film or an appropriate adhesive.

The first lid member 37 is generally a thin ceramic plate having elasticity. In the present embodiment, the first lid member 37 has a thickness of 1 mm.
It is made of zirconia (ZrO ₂ ) of about 0 μm. On the back surface (upper surface) of the first lid member 37, a common electrode 44 of the piezoelectric vibrator 35 is formed.
The piezoelectric vibrator 35 made of PZT or the like is laminated on the common electrode 44. The drive electrode 45 of the piezoelectric vibrator 35 is provided on the back surface (upper surface) of the piezoelectric vibrator 35.

The spacer member 38 is a ceramic plate having a through hole (opening) serving as the pressure generating chamber 36. In this case, the spacer member 38 is made of plate-like zirconia having a thickness of about 150 micrometers.

The second lid member 39 has a through hole as a supply side communication hole (ink supply port) 46 on the left side in FIG. 5A, and the first nozzle communication hole 4 on the right side in FIG.
7 is a ceramic material having a through hole. The second lid member 39 is made of, for example, plate-like zirconia.

The first (upper) surface of the spacer member 38 is
The lid member 37 has a second lid member 39 on the front surface (lower surface).
Are arranged respectively. That is, the spacer member 38 is sandwiched between the first lid member 37 and the second lid member 39. The first lid member 37, the second lid member 39, and the spacer member 38 are formed in an integrated manner by molding a clay-like ceramic material into a predetermined shape, and then laminating and firing the same. Is done.

The above-described ink supply port forming substrate 40 has a through hole as an ink supply port 48 on the left side and a first hole on the right side.
It is a plate-like member having a through hole as the nozzle communication hole 47. As shown in FIG. 5A, the ink supply port forming substrate 4
A concave portion 40r is formed in a part on the side of the zero pressure generation chamber 36 to form a thin portion 40t.

In the case of the present embodiment, the ink supply port forming substrate 40 is formed of a plate material in which two sheets of non-rusting steel are joined by an adhesive film, and one of the non-rusting steels is etched using the adhesive film as an etching stopper. The recess 40r is formed by performing the processing. However,
The thin portion 40t can also be formed by embossing with a press or the like and polishing the other protruding surface.

The reservoir forming substrate 41 is a plate-like member having a through hole (opening) as the common reservoir 49 and a through hole as the second nozzle communication hole 50 on the right side. In this case, it is made of a plate-like stainless steel having a thickness of about 150 micrometers. The opening as the reservoir 49 is located in a region below the thin portion 40t of the ink supply port forming substrate 40.

The nozzle plate 42 is a thin plate-like member having a large number, for example, 48, of nozzle openings 51 formed on the right side in a row along the sub-scanning direction, and may be formed of, for example, a stainless steel plate. The nozzle openings 51 are opened at a predetermined pitch corresponding to the dot formation density.

The front side (lower side) of the reservoir forming substrate 41
And an ink supply port forming substrate 40 on the back side (upper side). Between the reservoir forming substrate 41 and the nozzle plate 42, and between the reservoir forming substrate 41 and the ink supply port forming substrate 40
The ink supply port forming substrate 40, the reservoir forming substrate 41, and the nozzle plate 42 are integrated with each other to form the channel unit 34.

In the recording head 8 having such a configuration, the reservoir 49 of the flow path unit 34 and the supply side communication hole 46 of the actuator unit 33 communicate with each other through the ink supply port 48. Also, the supply side communication hole 46 and the first
The nozzle communication holes 47 communicate with each other via the pressure generating chamber 36. Further, the nozzle opening 51 and the first nozzle communication hole 47 communicate with each other via the second nozzle communication hole 50. Thus, a series of ink flow paths from the reservoir 49 to the nozzle opening 51 through the pressure generating chamber 36 is formed. The reservoir 49 is connected to an ink supply passage (not shown) through
The ink from the ink cartridge 19 is supplied. In the present embodiment, all ink supplied to each nozzle opening 51 is supplied via a common reservoir 49.

By changing the volume of the pressure generating chamber 36, an ink droplet can be ejected from the nozzle opening 51. Specifically, when the piezoelectric vibrator 35 is charged, the piezoelectric vibrator 35 contracts in a direction orthogonal to the electric field, and the first lid member 37 is deformed. The generation chamber 36 contracts. On the other hand, when the charged piezoelectric vibrator 35 is discharged, the piezoelectric vibrator 35 extends in a direction orthogonal to the electric field, and the first lid member 37 deforms in the return direction to expand the pressure generating chamber 36. When the pressure generating chamber 36 is once expanded and then contracted rapidly, the pressure generating chamber 36
5A, the ink pressure rises sharply, and ink droplets are ejected from the nozzle openings 51 as shown by the dashed line in FIG.

At this time, part of the ink in the pressure generating chamber 36 flows back to the reservoir 49 via the ink supply ports 46 and 48. The ink that has flowed back to the reservoir 49 causes pressure fluctuations in the ink in the reservoir 49. However, this pressure fluctuation is caused by the thin portion 40t of the ink supply port forming substrate 40.
Is absorbed by

Further, by expanding and contracting the pressure generating chamber 36 to such an extent that ink droplets are not ejected, the ink at the opening of the nozzle opening 51 can be agitated, and the viscosity of the ink at that portion can be prevented from increasing. . That is, when the pressure generating chamber 36 is expanded and contracted to such an extent that ink droplets are not ejected, as shown in FIG.
(The free surface of the ink exposed at the nozzle opening 51)
It moves alternately in the downward direction, which is the ink discharge direction, and in the upward direction, which is the ink withdrawal direction, and vibrates slightly. As a result, the ink at the nozzle opening can be stirred.

Next, the electrical configuration of the recording head 8 will be described. As shown in FIG. 1, the recording head 8 includes a shift register 55, a latch circuit 56, a level shifter 57, a switch 58, and a piezoelectric vibrator 35, which are electrically connected in order. Further, as shown in FIG. 6, the shift register 55, the latch circuit 56, the level shifter 57, the switch 58, and the piezoelectric vibrator 35
Shift register elements 55A to 55N, latch elements 56A to 56N provided for each nozzle opening 51 of the recording head 8,
Level shifter elements 57A to 57N, switch element 58A
To 58N and the piezoelectric vibrators 35A to 35N.

Information on the arrangement position of each nozzle opening 51 is sent to the mode bit signal generator 200 via, for example, the external I / F 3. In this case, the 48 nozzle openings 51 are alternately divided into two groups 51a and 51b, as shown in FIG. 7, and the information on which group each nozzle opening 51 belongs to is determined by the mode. The signal is sent to the bit signal generator 200.

The mode bit signal generator 200 generates, for each nozzle opening 51, a mode bit signal corresponding to the arrangement position of the nozzle opening 51. In this case, the mode bit signal is composed of 2-bit digital data of either "01" or "10", and corresponds to the group (first group 51a or second group 51b) to which the nozzle opening 51 belongs.
Two mode commands are realized.

Micro vibration signal generator 12 (or main signal generator 11), shift register 55, latch circuit 56, level shifter 57, switch 58, mode bit signal generator 2
The control unit 6 and the control unit 6 function as a micro-vibration control signal generation unit, that is, a non-printing common micro-vibration signal from the micro-vibration signal generation unit 12 and a micro-vibration mode signal (described later) based on the mode bit signal are combined. The micro vibration control signal is supplied to the recording head 8 (piezoelectric vibrator 35), or the in-print micro vibration control signal is generated from the ejection drive signal and supplied to the recording head 8.

The main signal generator 11, shift register 55, latch circuit 56, level shifter 57, switch 5
The control unit 8 and the control unit 6 function as a drive pulse supply unit, that is, generate a drive pulse from the ejection drive signal from the drive signal generation unit 9, and
To supply.

Next, control for discharging ink droplets will be described.

First, the case where the meniscus 52 is finely vibrated by the non-printing common fine vibration signal from the fine vibration signal generator 12 to stir the ink will be described.

In this case, the control unit 6 appropriately synchronizes the upper bit data of the mode bit signal from the mode bit signal generation unit 200 with the clock signal (CK) from the oscillation circuit 7, and Serial transmission is performed to sequentially set the shift register elements 55A to 55N. When the bit data for all the nozzle openings 51 are set in the shift register elements 55A to 55N, the control unit 6 sends the latch signal (LAT) to the latch circuit 56, that is, the latch elements 56A to 56N at a predetermined timing. ) Is output. With this latch signal, each latch element 56A
To 56N latch the bit data set in the shift register elements 55A to 55N. The latched bit data is supplied to a level shifter 5 which is a voltage amplifier.
7, that is, supplied to each of the level shifter elements 57A to 57N.

Each of the level shifter elements 57A to 57N (micro vibration mode signal generation means) has bit data of, for example, "1".
In the case of, the voltage value at which the switch 58 can be driven, for example,
The bit data is boosted up to several tens of volts to be a micro vibration mode signal (see FIG. 3). The boosted micro vibration mode signal is supplied to the switch 58, that is, the switch element 58.
A to 58N (signal fusion unit). The switch elements 58A to 58N are connected by the micro vibration mode signal. On the other hand, when the bit data is, for example, “0”, the corresponding level shifter elements 57A to 57N do not perform boosting.

A non-printing common micro-vibration signal from the micro-vibration signal generator 12 is applied to each of the switch elements 58A to 58N. When the switch elements 58A to 58N are connected, the non-printing common minute vibration signal is supplied to the piezoelectric vibrators 35A to 35N connected to the switch elements 58A to 58N.

When the non-printing common micro-vibration signal is applied based on the upper bit data, the control unit 6 then proceeds to
The lower bit data is transmitted serially and set in the shift register elements 55A to 55N. Then, when the bit data is set in the shift register elements 55A to 55N, the set bit data is latched by applying a latch signal, and the common non-printing minute vibration signal is supplied to the piezoelectric vibrators 35A to 35N. Let it.

When the vibration control signal is supplied to the piezoelectric vibrator 35, the pressure generating chamber 36 slightly expands and contracts, and
As described with reference to (b), the discharge side position near the opening edge of the nozzle opening 51 (shown by a dotted line in the figure) and the drawing side position closer to the pressure generating chamber 36 than this discharge side position (the solid line in the figure) ), The meniscus 52 slightly vibrates. That is, the ink in the nozzle opening is stirred. At this time, the ink in the reservoir 49 also vibrates, but the vibration (pressure fluctuation) is absorbed by the thin portion 40t, and the nozzle opening 51
The adverse effect of the vibration "rebounding" on the side of is surely avoided.

As described above, in the illustrated printer, whether or not the non-printing common micro-vibration signal is supplied to the piezoelectric vibrator 35 can be controlled by the mode bit signal. That is, the micro vibration control signal generated by ANDing the rectangular pulse micro vibration mode signal obtained by latching and boosting the bit data “1” of the mode bit signal and the non-printing micro vibration signal is a piezoelectric vibration signal. Is supplied to the child 35. When the bit data of the mode bit signal is “0”, the supply of the non-printing common fine vibration signal to the piezoelectric vibrator 35 is cut off. When the bit data is “0”, the piezoelectric vibrator 35 holds the previous charge (potential).

Therefore, by dividing the common micro-vibration signal in the time axis direction and setting each bit of the bit data of the mode bit signal corresponding to the divided portion, a plurality of micro-vibration control signals can be obtained from the common micro-vibration signal. The vibration control signal can be selectively generated, and the generated vibration control signal can be supplied to the piezoelectric vibrator 35. Thus, by generating the micro-vibration mode signal corresponding to each group of the nozzle openings 51 classified according to the arrangement position, it is possible to realize the micro-vibration control with a substantially time difference, and to control the wetting around the nozzle openings. Evils are more effectively avoided.

In this example, as shown in FIG. 3, the common micro-vibration signal is composed of a periodic signal in which a trapezoidal pulse 201 whose potential switches between a minimum potential and a maximum potential is connected in series. The mode bit signal is, for each nozzle opening 51, a group (first group 5) to which the nozzle opening 51 belongs.
"10" or "01" is generated according to 1a or the second group 51b).

Then, as shown in FIG. 3, the first group 51a
And the pulse waveform for the nozzle openings 51 belonging to the second group 51b are supplied in a time relationship that is alternately shifted.

Thus, even when the pressure fluctuation absorbing capacity of the common reservoir 49 is small, wetting around the nozzle opening can be avoided more effectively. The pressure fluctuation absorbing capacity of the common reservoir 49 can be represented by the compliance per nozzle of the thin portion 40t. In this case, to achieve the same compliance per nozzle,
Since the compliance of is sufficient, the size of the recording head 8 can be reduced as a result.

Next, a procedure for applying a drive pulse to the piezoelectric vibrator 35 will be described. In the following description, a case will be described where each piece of print data (corresponding to one dot data) constituting the dot pattern data is composed of 4 bits.

In this case, the control unit 6 sends the print data (S
The data of the most significant bit in I) is serially transmitted from the output buffer 4C by appropriately synchronizing with the clock signal (CK) from the oscillation circuit 7, and the shift register element 55
A to 55N are sequentially set. When the print data for all the nozzle openings 51 is set in each of the shift register elements 55A to 55N, the control unit 6 issues a predetermined timing.
To the latch circuit 56, that is, to each of the latch elements 56A to 56N,
The latch signal (LAT) is output. With this latch signal, each of the latch elements 56A to 56N latches the print data set in each of the shift register elements 55A to 55N. The latched print data is supplied to the level shifter 57 as a voltage amplifier, that is, each level shifter element 57A.
~ 57N.

When the print data is, for example, "1", each of the level shifter elements 57A to 57N (main mode signal generating means) boosts the print data to a voltage value at which the switch 58 can be driven, for example, several tens of volts. To obtain a main mode signal (see FIG. 2). The boosted main mode signal is supplied to the switch 58, that is, the switch elements 58A to 58N.
Is applied to The switch elements 58A to 58N are connected by the main mode signal. On the other hand, when the print data is, for example, “0”, the corresponding level shifter elements 57A to 57N do not perform boosting.

An ejection drive signal (COM) from the main signal generator 11 is applied to each of the switch elements 58A to 58N. When the switch elements 58A to 58N are connected, the ejection drive signal is supplied to the piezoelectric vibrators 35A to 35N connected to the switch elements 58A to 58N.

After the application of the ejection drive signal based on the data of the most significant bit, the control unit 6 serially transmits the data of one bit lower and sets it in the shift register elements 55A to 55N. Then, if data is set in the shift register elements 55A to 55N,
By applying the latch signal, the set data is latched, and the ejection drive signal is transmitted to the piezoelectric vibrators 35A to 35A.
5N. Thereafter, the same operation is repeated up to the least significant bit while shifting the print data to lower bits one bit at a time.

As described above, in the illustrated printer, whether or not the ejection drive signal is supplied to the piezoelectric vibrator 35 can be controlled by the print data. That is, a driving pulse signal generated by ANDing the rectangular pulse-shaped main mode signal obtained by latching and boosting the bit “1” of the print data and the ejection driving signal is supplied to the piezoelectric vibrator 35.
When the bit of the print data is “0”, the supply of the ejection drive signal to the piezoelectric vibrator 35 is cut off. When the bit of the print data is set to “0”, the piezoelectric vibrator 35 holds the electric charge (potential) immediately before.

Therefore, by dividing the ejection drive signal in the time axis direction and setting each bit of the print data in accordance with the divided portion, a plurality of drive pulses and a plurality of fine vibrations in printing can be obtained from one ejection drive signal. The signal can be selectively generated, and the generated driving pulse or the in-print fine vibration signal can be supplied to the piezoelectric vibrator 35. Accordingly, the meniscus 52 is finely vibrated with an appropriate intensity during printing to obtain a sufficient ink stirring effect without adverse effects such as wetting and bending, or a plurality of driving pulses having different amounts of ink droplets (that is, dot diameters) are used. It can be supplied to the piezoelectric vibrator 35 of the recording head 8.

For example, in the example shown in FIG. 2, the ejection drive signal is supplied to the first waveform section 61, the second waveform section 62, and the third waveform section 6.
Third, the first waveform section 61 generates a small dot drive pulse, the fourth waveform section 64 generates a medium dot drive pulse, and the first waveform section 61 and the fourth waveform section 64. To generate a large dot drive pulse, and a second waveform portion (pulse portion) 62 to generate a print in-vibration control signal for the nozzle openings 51 belonging to the first group 51a.
The waveform portion (pulse portion) 63 generates an in-print slight vibration control signal for the nozzle openings 51 belonging to the second group 51b.

Here, the small dot drive pulse is a drive pulse for discharging an ink droplet capable of forming a small dot.
The medium dot drive pulse is a drive pulse for discharging an ink droplet capable of forming a medium dot, and the large dot drive pulse is a drive pulse for discharging an ink droplet capable of forming a large dot. Further, each in-print vibration control signal is a drive pulse for finely vibrating the meniscus 52 with respect to the nozzle openings 51 of the first group 51a or the second group 51b that does not eject ink droplets.

Thus, the in-print micro-vibration signal for the nozzle openings 51 belonging to the first group 51a and the in-print micro-vibration signal for the nozzle openings 51 belonging to the second group 51b are:
They are supplied at different times.

Then, the micro-vibration signal in the print is transmitted to the piezoelectric vibrator 3.
5, the pressure generating chamber 36 slightly expands and contracts, and as described with reference to FIG.
The meniscus 52 slightly oscillates between a discharge side position (shown by a dotted line in the figure) near the opening edge of No. 1 and a drawing side position (shown by a solid line in the figure) closer to the pressure generating chamber 36 than the discharge side position. I do. That is, the ink in the nozzle opening is stirred.

By controlling the in-print microvibration with such a time lag, even when the pressure fluctuation absorbing ability of the common reservoir 49 is small, wetting around the nozzle opening can be avoided more effectively. In this case, in order to realize the compliance per nozzle of the thin portion 40t, 1 / l of the conventional one is used.
2 is sufficient, so that the recording head 8 can be reduced in size.

In this example, the print data is composed of 4-bit data D1, D2, D3 and D4, and by setting each data to D1 = 1, D2 = 0, D3 = 0 and D4 = 0, a small dot is set. A drive pulse is generated, and each data is set to D1 =
By setting 0, D2 = 0, D3 = 0, and D4 = 1, a medium dot drive pulse is generated, and each data is D1 = 1, D2
= 0, D3 = 0, D4 = 1, a large dot drive pulse is generated, and each data is D1 = 0, D2 = 1, D
By setting 3 = 0 and D4 = 0, an in-print micro-vibration pulse for the nozzle openings 51 belonging to the first group 51a is generated, and each data is D1 = 0, D2 = 0, D3 = 1, D4 = 0. Is set to generate a micro-vibration pulse in printing for the nozzle openings 51 belonging to the second group 51b. Each data is represented by D1 = 0, D2 = 0, D3 = 0, D4 =
If it is set to 0, even the in-print microvibration control is not performed.

Here, the data D2 and D3 of the middle two bits of the print data may use a mode bit signal. For example, when the uppermost and lowermost two bits D1 and D4 of the print data are both 0, the upper and lower bit data of the mode bit signal are input to D2 and D3,
When at least one of the most significant and least significant two bits D1 and D4 of the print data is not 0, by inputting 0 to both D2 and D3, it is possible to generate the same drive pulse and fine vibration pulse in print as described above. it can. In this case, the substantial print data consists of two bits D1 and D4, so that the processing can be simplified and speeded up.

However, the number of bits of the print data and the waveform and type of the micro-vibration pulse in the print can be appropriately selected. The number of in-print micro-vibration pulses is the same as the number of types of mode bit signals in out-of-print micro-vibration control, and is preferably the same as the number of groups into which the nozzle openings 51 are separated, but is the same. No need.

Next, the recording operation of the printer having the above configuration will be described. In this printer, the meniscus 52 is finely vibrated as needed in conjunction with one main scan (recording operation of one line) of the recording head 8 in order to prevent the ink from increasing in viscosity. Specifically, the recording head 8 (carriage 2
During the acceleration period 1), immediately before the start of recording, and in each state during the recording operation, the meniscus 52 is slightly vibrated.

In the following description, as shown in FIG. 8, the image 18X is located in the area of the recording paper 18 opposite to the home position HP, that is, in the latter half of one line.
Will be described.

FIG. 8 is a timing chart for explaining recording (printing) of one line. In FIG.
The recording paper 18 is also shown, and the correspondence between the recording position of the recording head 8 and time is also shown. FIG. 9 is a flowchart illustrating a dot pattern development process.
FIG. 10 is a flowchart for explaining the dot pattern recording process and the position information acquisition process performed by interrupting the dot pattern recording process.

This recording operation is based on the intermediate code data.
It is broadly divided into a dot pattern development process for generating dot pattern data for a row and a dot pattern recording process for recording on the recording paper 18 based on the developed dot pattern data.

Hereinafter, each of these processes will be described.

In the dot pattern development process shown in FIG.
The control unit 6 first functions as a dot pattern data generation unit, and generates dot pattern data for one row.
That is, the intermediate code data stored in the intermediate buffer 4B is read (S1), and the read intermediate code data is developed into dot pattern data based on the font data and the graphic function of the ROM 5 (S2), and the developed dot data is obtained. The pattern data is stored in the output buffer 4C (S3). Then, this development work is repeatedly executed until a dot pattern for one line is stored (S4).

When one line of dot pattern data has been stored in the output buffer 4C (S4), the control section 6 functions as a recording start position information setting means and performs recording indicating the recording start position in the printing range of one line. The start position information is set (S5). The recording start position is a position where the first ink droplet is ejected in the main scanning direction. In the example of FIG. 8, the recording start position is indicated by reference numeral P1.

The recording start position information in the present embodiment is set in accordance with the count value corresponding to the slit 28 of the linear encoder 27, that is, the count value of the pulse PS output from the slit detector 29. .

Subsequently, the control section 6 transfers the developed dot pattern data to the recording head 8 (S6). Triggered by the transfer of the dot pattern data, the printing operation of the image for one line is started, and the printing head 8 is main-scanned. Then, in conjunction with this main scanning, fine vibration control is performed in which the meniscus 52 is finely vibrated to agitate the ink.
At the time of execution of the micro-vibration control, the control unit 6
Functions as micro vibration control means.

With the transfer of the dot pattern data, the control section 6 performs a dot pattern recording process. In this dot pattern recording process, the control unit 6 first functions as a non-printing microvibration control unit (a type of microvibration control unit), and stirs ink (microvibration) during the acceleration period of the carriage 21.
Is performed. That is, triggered by the transfer of the dot pattern data, the control unit 6 supplies the non-printing common fine vibration signal from the fine vibration signal generation unit 12 to the piezoelectric vibrator 35 of the recording head 8.

In this process, as shown in FIGS. 8 and 10, the control section 6 starts supplying the non-printing common micro-vibration signal (S11, t0), and thereafter starts scanning of the recording head 8 (S12). , T1). Further, for example, at the timing immediately before the recording head 8 switches from the acceleration state to the constant speed state, the supply of the non-printing common micro vibration signal is stopped (S1).
3, t2).

In this series of processing, the control section 6 first outputs a control signal to the selection section 13 so that the non-printing common fine vibration signal from the fine vibration signal generation section 12 can be supplied. Then, by setting each bit data of the mode bit signal in the shift register 55 and supplying a latch signal, a vibration control signal corresponding to the arrangement position of the nozzle opening 51 is generated and supplied to the piezoelectric vibrator 35. (See FIG. 3). Thereafter, the control unit 6 supplies an operation pulse to the pulse motor 25 and moves the carriage 21 in the main scanning direction to scan the recording head 8. When the timing of stopping the non-printing micro-vibration signal is reached, the supply of the non-printing common micro-vibration signal from the micro-vibration signal generating unit 12 is stopped to stop the non-printing micro-vibration. The stop timing of the non-printing vibration control signal may be set as a timing at which a predetermined number of pulse waveforms of the non-printing vibration control signal are supplied.

By the way, when the recording head 8 is scanned,
Along with this scanning, a slit detector 29 provided on the carriage 21 detects the slit 28 of the linear encoder 27 and outputs a pulse-like detection signal (a signal indicated by a symbol PS in FIG. 8). The control unit 6 monitors the detection signal, and executes the position information acquisition processing upon receiving the detection signal. This position information acquisition process is a process executed by interrupting the dot pattern recording process.
As shown in (b), this is a process of counting up (+1) the position counter (S21). Specifically, based on the detection signal from the slit detector 29, the count value of the position counter as the head position information is updated by adding +1. When the position counter has counted up, the process returns to the dot pattern recording process. The count value of the position counter is reset when the scanning of the recording head 8 for one row is stopped or when the recording head 8 returns to the reference position.

When the supply of the non-printing common micro-vibration signal is stopped, the control section 6 outputs a control signal to the selection section 13 of the drive signal generation section 9 and outputs the ejection drive signal from the main signal generation section 11. Is set in a state where it can be supplied (S14).

When the ejection drive signal can be supplied, the control section 6 functions as recording start timing determining means and determines whether or not the recording start timing has come (S15). In the present embodiment, the control unit 6 monitors the count value of the position counter, and determines that the recording start timing has come when the count value reaches the count value corresponding to the recording start position P1 ( t
4).

If it is determined that the recording start timing has come, the control section 6 supplies an ejection drive signal to record an image on the recording paper 18 (S16). In this case, FIG.
As described in, based on the dot pattern data,
Any one of a small dot drive pulse, a medium dot drive pulse, a large dot drive pulse, and a fine vibration pulse in each print is supplied to each of the piezoelectric vibrators 35A to 35N. By supplying these drive pulses, each nozzle opening 51
From this, ink droplets capable of forming small dots, medium dots or large dots are ejected.

The nozzle opening 5 which does not discharge ink droplets
With respect to 1, the meniscus 52 is finely vibrated by supplying the in-print fine vibration signal corresponding to the arrangement position of the nozzle opening 51, and the ink in the nozzle opening is stirred.

With such control, the ink droplets are ejected in a state where the ink viscosity has returned to the normal viscosity due to the slight vibration of the meniscus 52 performed immediately before. For this reason, even the first ink droplet ejected in a certain row can be caused to fly accurately in a predetermined direction. Therefore, even when the amount of ink droplets to be ejected is reduced and the viscosity of the ink tends to increase, it is possible to effectively prevent the image quality from deteriorating at the recording start portion. In particular, the first group 5
Since the in-print micro-vibration signal for the nozzle opening 51 belonging to the first group 1a and the in-print micro-vibration signal for the nozzle opening 51 in the second group 51b are supplied with a time lag, the nozzle opening is controlled by the in-print micro vibration control. The surrounding area can be reliably prevented from getting wet.

In particular, when large-sized recording paper is used, the state in which ink droplets are not ejected for a relatively long time tends to increase ink viscosity. However, even in such a case, by adopting the above-described control, it is possible to reliably prevent the image quality from deteriorating at the recording start portion.

When the recording operation for one line is completed, the pulse motor 25 is stopped (S17). After that, the recording head 8 is moved to the home position HP and positioned at the reference position. After that, the same recording operation is repeated for the next one line.

In the above embodiment, the recording head 8 using the so-called flexural vibration mode piezoelectric vibrator 35 has been exemplified. Instead of the recording head 8, a longitudinal vibration mode piezoelectric vibrator 73 is used. A recording head 70 may be used.

As shown in FIG. 11, in the recording head 70 in the longitudinal vibration mode, a comb-shaped piezoelectric vibrator 73 is inserted from one opening into a storage chamber 72 of a box-shaped case 71 made of, for example, plastic. Inserted comb-shaped tip 73a
Faces the other opening. A channel unit 74 is joined to the surface (lower surface) of the case 71 on the other opening side,
The comb-shaped tip portions 73a are abutted and fixed to predetermined portions of the flow path unit 74, respectively.

The piezoelectric vibrator 73 is obtained by cutting a plate-like vibrator plate in which common internal electrodes 73c and individual internal electrodes 73d are alternately laminated with a piezoelectric body 73b interposed therebetween in a comb-teeth shape corresponding to the dot formation density. It is configured. By applying a potential difference between the common internal electrode 73c and the individual internal electrode 73d, each piezoelectric vibrator 73 expands and contracts in the vibrator longitudinal direction orthogonal to the laminating direction.

The channel unit 74 is configured by laminating a nozzle plate 76 and an elastic plate 77 on both sides with a channel forming plate 75 interposed therebetween.

The flow path forming plate 75 is provided with a plurality of pressure generating chambers 81 which are communicated with the plurality of nozzle openings 80 formed in the nozzle plate 76 and are arranged in a row with the pressure generating chamber partition walls therebetween.
This is a plate member in which a plurality of ink supply units 82 communicating with at least one end of each pressure generating chamber 81 and an elongated common ink chamber 83 communicating with all the ink supply units 82 are formed. For example, by etching a silicon wafer, an elongated common ink chamber 83 is formed, and the pressure generating chamber 81 is formed in the nozzle opening 8 along the longitudinal direction of the common ink chamber 83.
A groove-shaped ink supply section 82 may be formed between each pressure generating chamber 81 and the common ink chamber 83 so as to be formed at a pitch of 0. In this case, an ink supply unit 82 is connected to one end of the pressure generating chamber 81, and the nozzle opening 80 is located near the end opposite to the ink supply unit 82. Further, the common ink chamber 83 is a chamber for supplying the ink stored in the ink cartridge to the pressure generating chamber 81, and an ink supply pipe 84 communicates with substantially the center in the longitudinal direction.

The elastic plate 77 is laminated on the surface of the flow path forming plate 75 on the side opposite to the nozzle plate 76, and the stainless plate 8
A polymer film such as PPS is coated on the lower surface of
8 is a double structure laminated. And
The stainless plate 87 corresponding to the pressure generating chamber 81 is etched to form an island portion 89 for abutting and fixing the piezoelectric vibrator 73.

In the recording head 70 having the above configuration,
By extending the piezoelectric vibrator 73 in the longitudinal direction of the vibrator, the island portion 89 is pressed toward the nozzle plate 76, the elastic film 88 around the island portion 89 is deformed, and the pressure generating chamber 81 contracts. When the piezoelectric vibrator 73 is contracted in the longitudinal direction from the contracted state of the pressure generating chamber 81, the pressure generating chamber 81 expands due to the elasticity of the elastic film 88. When the pressure generating chamber 81 is once expanded and then contracted, the ink pressure in the pressure generating chamber 81 increases, and ink droplets are ejected from the nozzle openings 80.

Also in such a recording head 70, the meniscus can be finely vibrated by expanding and contracting the piezoelectric vibrator 73 to the extent that ink droplets are not ejected, and the ink at the nozzle opening can be agitated.

Further, in the above-described embodiment, the control section 6 functioning as the micro-vibration control means is provided with the drive signal generation section 9.
Although the drive signal generated by the (main signal generation unit 11 and micro vibration signal generation unit 12) is supplied to the recording head 8,
The micro vibration control means is not limited to this configuration.

In the above-described embodiment, the recording start position information setting means sets the recording start position of the recording head 8 based on the dot pattern data. Not limited. For example, the recording start position may be set based on print data (corresponding to one type of recording data) from the host computer, or may be set based on intermediate data (corresponding to one type of recording data).

In the above description, the printer having the recording head 8 for expanding and contracting the pressure generating chamber 36 by using the piezoelectric vibrator 35 has been described. The present invention can also be applied to a printer or a plotter having a so-called bubble jet (registered trademark) type recording head that discharges ink droplets from nozzle openings by changing the size of the bubbles.

Next, an ink jet recording apparatus according to a second embodiment of the present invention will be described with reference to FIGS. FIG. 12 is a diagram illustrating a manner of sorting the nozzle openings 51 in the present embodiment. FIG. 13 illustrates a non-printing common micro-vibration signal generated by the micro-vibration signal generating unit 12 of the ink jet recording apparatus according to the present embodiment, and a micro-vibration control signal generated based on the non-printing common micro-vibration signal. FIG.

As shown in FIG. 12, in the case of the present embodiment, forty-eight nozzle openings 51 have three groups 5 every three nozzle openings 51.
1a, 51b, and 51c, and information on which group each nozzle opening 51 belongs to is sent to the mode bit signal generator 200.

In this case, the mode bit signal is "10
A group (first group 51a, second group 51b, or third group 51c) composed of 3-bit digital data of any one of "0", "010", and "001" and to which nozzle opening 51 belongs.
Are realized.

Then, as shown in FIG. 13, the first group 51
a pulse waveform for the nozzle opening 51 belonging to
The pulse waveforms for the nozzle openings 51 belonging to the group 51b and the pulse waveforms for the nozzle openings 51 belonging to the third group 51c are supplied in a temporally shifted relationship.

The other structure is substantially the same as that of the first embodiment described with reference to FIGS. Second
In this embodiment, the same parts as those in the first embodiment shown in FIGS. 1 to 11 are denoted by the same reference numerals, and detailed description thereof will be omitted.

According to the present embodiment, since the number of nozzle openings for which the micro-vibration control outside the print is simultaneously performed is 18,
Even when the pressure fluctuation absorbing ability of the common reservoir is small, wetting around the nozzle opening can be further effectively avoided.

Although a detailed description is omitted, if the number of pulse waveforms included in the ejection drive signal for in-print micro-vibration is set to three, the number of nozzle openings for which the in-print micro-vibration control is performed simultaneously Can also be set to 18.

As described above, if the number of groups for separating the nozzle openings 51 is increased and micro-vibration control is performed for each group, the probability of occurrence of wetting around the nozzle openings can be further reduced. However, it is necessary to consider that one cycle of the common micro-vibration signal (or the ejection drive signal) becomes longer.

Next, an ink jet recording apparatus according to a third embodiment of the present invention will be described with reference to FIGS. FIG. 14 is a schematic block diagram illustrating the configuration of an ink jet recording apparatus according to the third embodiment of the present invention. As shown in FIG. 14, the ink jet recording apparatus according to the present embodiment has a mode bit signal generator 2
Does not have 00.

The micro-vibration signal generator 12 according to the present embodiment, as shown in FIG. 15, controls the first micro-vibration control for the nozzle openings 51 belonging to the first group 51a in accordance with the position of the nozzle openings 51. It is possible to generate both a signal and a second vibration control signal for the nozzle opening 51 belonging to the second group 51b.

In this example, as shown in FIG. 15, the first vibration control signal is constituted by a periodic signal in which a trapezoidal pulse 301 whose potential is switched between a minimum potential and a maximum potential is connected in series. I have.

Similarly, the trapezoidal pulse 30 whose potential switches between the minimum potential and the maximum potential is also used as the second micro vibration control signal.
2 are connected in series to form a periodic signal.

Each of the trapezoidal pulses 301 and 302 has the same waveform. Furthermore, the frequencies of appearance of the pulses 301 and 302 in each micro vibration control signal are the same. However, the appearance periods of the pulses 301 and 302 in each of the vibration control signals are alternately shifted.

Therefore, for example, the second vibration control signal is
It can be generated by passing a micro control signal through a delay circuit or the like.

Since the ink jet recording apparatus of the present embodiment does not have the mode bit signal generating section 200, each micro vibration control signal is used as it is as a micro vibration control signal. (Even when the mode bit signal generation unit 200 is provided, the same mode is applied when the signal “1” is always output.) The other configuration is the first described with reference to FIGS. 1 to 11.
The configuration is substantially the same as that of the embodiment. In the third embodiment, the same parts as those in the first embodiment shown in FIGS. 1 to 13 are denoted by the same reference numerals, and detailed description is omitted.

According to the present embodiment, the pulse waveform for the nozzle openings 51 belonging to the first group 51a and the second group 5
The pulse waveform for the nozzle opening 51 belonging to 1b is
They are supplied in a staggered time relationship.

As a result, even when the pressure fluctuation absorbing ability of the common reservoir is small, wetting around the nozzle opening can be avoided more effectively.

For forming each pulse waveform, it is preferable to use the method described in Japanese Patent No. 2940542. The contents described in the patent specification are:
This reference is incorporated herein by reference.

As described above, the printer controller 1 is constituted by a computer system. However, a computer-readable recording medium on which a program for causing the computer system to realize each of the above-described components is also covered by the present invention. It is.

Further, when each of the above-described elements is realized by a program such as an OS operating on a computer system, a recording medium storing a program including various instructions for controlling the program of the OS or the like is also protected by the present invention. The subject.

The present invention can be applied to any liquid ejecting apparatus other than the ink jet type recording apparatus. As an example of the liquid, glue, nail polish, or the like may be used in addition to ink.

[0144]

As described above, according to the present invention,
The micro-vibration control signal generation means generates a micro-vibration control signal for each group of nozzle openings classified based on the arrangement position, and the micro-vibration means is driven based on the micro-vibration control signal. Suitable fine vibration control according to the pressure fluctuation absorbing ability can be realized.

If a part of the common reservoir is partitioned by the thin portion, the pressure fluctuation absorbing ability of the common reservoir is improved.

In the case where a plurality of nozzle openings are arranged in a row, if a time difference is provided for the micro-vibration control of the adjacent nozzle openings, even if the pressure fluctuation absorbing ability of the common reservoir is small, the vicinity of the nozzle openings can be more effectively reduced. Can be avoided.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram illustrating a configuration of an ink jet recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an ejection drive signal and a drive pulse generated based on the ejection drive signal.

FIG. 3 is a diagram illustrating a micro vibration control signal.

FIG. 4 is a perspective view of the ink jet recording apparatus of FIG.

5A and 5B are diagrams illustrating the structure of a recording head, and FIG.
Is a sectional view, and (b) is an enlarged sectional view of a portion A in (a).

FIG. 6 is a block diagram illustrating an electrical configuration of the recording head.

FIG. 7 is a view for explaining a mode of sorting the nozzle openings of FIG. 1;

FIG. 8 is a timing chart illustrating a recording operation of one row.

FIG. 9 is a flowchart illustrating a dot pattern development process.

10A is a flowchart illustrating a dot pattern recording process, and FIG. 10B is a flowchart illustrating a position information acquisition process.

FIG. 11 is a diagram illustrating a recording head using a piezoelectric vibrator in a longitudinal vibration mode.

FIG. 12 is a diagram illustrating a mode of sorting nozzle openings in an ink jet recording apparatus according to a second embodiment.

FIG. 13 is a diagram illustrating a micro-vibration control signal according to the second embodiment.

FIG. 14 is a schematic block diagram illustrating a configuration of an ink jet recording apparatus according to a third embodiment of the present invention.

FIG. 15 is a diagram illustrating a micro-vibration control signal according to the third embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer controller 2 Print engine 3 External interface 4 RAM 5 ROM 6 Control part 7 Oscillation circuit 8 Recording head 9 Drive signal generation part 9a Second correction rate determination part 9b First correction rate determination part 10 Internal interface 11 Main signal generation part 12 Micro vibration signal generator 13 Selector 16 Paper feed mechanism 17 Carriage mechanism 18 Recording paper 19 Ink cartridge 20 Guide member 21 Carriage 22 Drive pulley 23 Follower pulley 24 Timing belt 25 Pulse motor 26 Printer housing 27 Linear encoder 28 Slit 29 Slit detection Container 30 Capping mechanism 33 Actuator unit 34 Channel unit 35 Piezoelectric vibrator 36 Pressure generating chamber 37 First lid member 38 Spacer member 39 Second lid member 40 Ink supply port forming substrate 40r recess 40t thin portion 41 reservoir forming substrate 42 nozzle plate 43 adhesive layer 44 common electrode 45 drive electrode 46 supply side communication hole 47 first nozzle communication hole 48 ink supply port 49 reservoir 50 second nozzle communication hole 51 nozzle opening 52 meniscus 55 Shift register 56 latch circuit 57 level shifter 58 switch 61 first waveform section 62 second waveform section 63 third waveform section 64 fourth waveform section 61t to 64t waveform 70 recording head 71 case 72 storage chamber 73 piezoelectric vibrator 73a comb-shaped Tip part 74 Flow path unit 75 Flow path forming plate 76 Nozzle plate 77 Elastic plate 80 Nozzle opening 81 Pressure generation chamber 82 Ink supply part 83 Common ink chamber 84 Ink supply pipe 87 Stainless steel plate 88 Elastic film 89 Island part 201 Trapezoidal pulse 301 Trapezoid Luz 302 trapezoidal pulse

Claims (22)

[Claims] 1. A plurality of nozzle openings, each of which is separated into a plurality of groups based on an arrangement position, a common reservoir for storing liquid, and a liquid for supplying liquid from the common reservoir to the plurality of nozzle openings. A head member having a flow path, fine vibration means for finely vibrating the liquid in the nozzle opening portion for each group of separated nozzle openings, and a fine vibration generating signal for generating a fine vibration control signal for each group of separated nozzle openings. A liquid ejecting apparatus comprising: a vibration control signal generating unit; and a micro vibration control unit that drives the micro vibration unit based on the micro vibration control signal. 2. The liquid ejecting apparatus according to claim 1, wherein at least a part of the common reservoir is defined by a thin portion. 3. The liquid ejecting apparatus according to claim 1, wherein the plurality of nozzle openings are arranged in a row, and adjacent nozzle openings are separated into different groups. 4. The liquid ejecting apparatus according to claim 3, wherein the plurality of nozzle openings are divided into n groups every n nozzles. 5. The liquid ejecting apparatus according to claim 4, wherein the plurality of nozzle openings are alternately divided into two groups. 6. A vibration control signal generated for each group of separated nozzle openings has a continuous pulse waveform, and the pulse waveform of each vibration control signal is substantially the same, The frequency of appearance of the pulse waveform of each vibration control signal is substantially the same, and the frequency of appearance of the pulse waveform of each vibration control signal is shifted for each vibration control signal. 6. The liquid ejecting apparatus according to any one of 5. 7. A micro-vibration signal generating means for generating a common micro-vibration signal, a micro-vibration mode signal generating means for generating a micro-vibration mode signal for each group of separated nozzle openings. The liquid according to any one of claims 1 to 6, further comprising: a signal fusion unit that generates a vibration control signal based on the common vibration signal and the vibration mode signal. Injection device. 8. The liquid according to claim 7, wherein the signal fusion unit generates a vibration control signal by ANDing the common vibration signal and the vibration mode signal. Injection device. 9. The common fine vibration signal is a periodic signal having a predetermined waveform, and the fine vibration mode signal is a periodic signal having a predetermined rectangular pulse train and having the same period as the common fine vibration signal. The liquid ejecting apparatus according to claim 8, wherein 10. The liquid ejecting apparatus according to claim 1, wherein the liquid is ink, and the head member is a recording head. 11. A plurality of nozzle openings, each of which is separated into a plurality of groups based on an arrangement position, a common reservoir for storing liquid, and a liquid for supplying liquid from the common reservoir to the plurality of nozzle openings. A head member having a flow path, and fine vibration means for finely vibrating the liquid in the nozzle opening portion for each group of the separated nozzle openings. A fine vibration control signal generating means for generating a fine vibration control signal for each of the sorted groups of nozzle openings; and a fine vibration control means for driving the fine vibration means based on the fine vibration control signal. A control device, comprising: 12. The common reservoir according to claim 11, wherein at least a part thereof is defined by a thin portion.
The control device according to claim 1. 13. The control device according to claim 11, wherein the plurality of nozzle openings are arranged in rows, and adjacent nozzle openings are classified into different groups. 14. The control device according to claim 13, wherein the plurality of nozzle openings are separated into n groups every n nozzle openings. 15. The liquid ejecting apparatus according to claim 14, wherein the plurality of nozzle openings are alternately divided into two groups. 16. Each of the fine vibration control signals generated for each of the separated groups of nozzle openings has a continuous pulse waveform, and the pulse waveforms of the fine vibration control signals are substantially the same. The appearance frequency of the pulse waveform of each micro vibration control signal is substantially the same, and the appearance cycle of the pulse waveform of each micro vibration control signal is shifted for each micro vibration control signal. 1
6. The control device according to any one of 5. 17. A vibration control signal generating means for generating a vibration signal for generating a common vibration signal, a vibration mode signal generating means for generating a vibration mode signal for each group of separated nozzle openings. The control according to any one of claims 11 to 16, further comprising: a signal fusion unit that generates a vibration control signal based on the common vibration signal and the vibration mode signal. apparatus. 18. The signal fusion unit according to claim 17, wherein a fine vibration control signal is generated by ANDing the common fine vibration signal and the fine vibration mode signal.
The control device according to claim 1. 19. A periodic signal having a predetermined waveform, wherein the common micro-vibration signal is a periodic signal having a predetermined waveform, and a periodic signal having a predetermined rectangular pulse train and having the same period as the common micro-vibration signal. The control device according to claim 18, wherein: 20. The control device according to claim 11, wherein the liquid is ink, and the head member is a recording head. 21. A computer-readable recording medium that is executed by a computer system including at least one computer and records a program for causing the computer system to implement the control device according to claim 11. 22. An instruction for controlling a second program operating on a computer system including at least one computer, the program being executed by the computer system to control the second program, 21. A computer-readable recording medium on which a program for causing the computer system to implement the control device according to claim 11 is recorded.