JPH07329298A - Recording head and recorder using the same - Google Patents

Abstract

PURPOSE:To provide a small-sized recording head and a recorder having the same head which can record at a high speed and high quality. CONSTITUTION:A recording head has an ink jet discharge port to simultaneously record the recording width of a recording medium, and comprises a plurality of driving ICs 23 for controlling ink jet discharges from a plurality (e.g., 64) of discharge ports. Image clocks (CLK) and a pulse width setting signal (ENB) are externally cascade connected to the ICs 23 in such a manner that the signals are so regulated as to satisfy specific reference for all the ICs 23 in the pulse widths of the signals by correcting circuits 31, 32 provided in the ICs 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head and a recording apparatus equipped with the recording head, and more particularly, to a recording head according to the ink jet system in which thermal energy is used to eject ink droplets from the ejection port, and the recording head. Recording device.

[0002]

2. Description of the Related Art An ink jet type recording apparatus is a recording apparatus for forming an ink discharge droplet by various methods and adhering it to a recording material such as recording paper to record an image. Among them, an ink jet recording apparatus that uses heat as energy for forming discharged droplets has a high density of nozzles that discharge droplets, so that it is possible to obtain high-resolution and high-quality images at high speed. It has the outstanding feature to say.

In such an ink jet recording apparatus,
A plurality of droplet forming means for ejecting ink droplets from the ejection port by applying thermal energy to the ink, that is,
Droplet forming means having an electrothermal converter capable of generating heat by supplying a current pulse to heat the ink;
An integrated circuit for driving the electrothermal converter (driving I
Some of them have a recording head in which a plurality of C and C are arranged on the same substrate.

FIG. 6 shows a recording head 20 having the above structure.
And FIG. 7 is a block diagram showing the configuration of a driver circuit 30 for driving the print head and FIG. 7 is a time chart showing the drive timing thereof.

In FIG. 6, 21 is an electrothermal converter provided corresponding to a plurality of ink ejection openings (not shown) of the recording head, and 23 is a plurality of ejection openings (or electrothermal conversion body 2).
It is an integrated circuit (referred to as a driving IC) for ejecting ink jet from 1). Electrothermal converter 21
As shown in the timing chart of FIG. 7, the recording data (SI) having the same number of bits as the above is synchronized with the data transfer clock (CLK) supplied from the image data generating circuit 22 of the driver circuit 30 to the shift register 24. Then, the transferred record data is read into the latch circuit 25 by the latch signal (LAT) supplied from the drive timing generation circuit 29. After that, the flip-flop (F / F) 26 belonging to each driving IC 23 is input in response to the input of the energization instruction signal (EI) and the energization instruction signal transfer clock (ECK) supplied from the drive timing generation circuit 29.
The pulse signals are sequentially supplied to the current-carrying body driving IC 27 from. Under these conditions, the pulse width setting signal (E
NB) is supplied at the timing as shown in FIG. 7, the current-carrying body driving ICs 27 belonging to the respective driving ICs 23 are sequentially activated, and the pulse width setting signal (E
Only while “NB” is “ON”, the electrothermal converter 21 is selectively energized, and ink is ejected from the ink ejection port. In this case, the frequency of the image data transfer clock (CLK) is generally several MHz, and the energization time for one electrothermal converter is generally several μs. It should be noted that the heater driving power supply circuit 28 is always supplied with the predetermined voltage VM for each of the electric conductors of the electrothermal converter 21.
Is being applied more. The GND output from the heater driving power supply circuit 28 is grounded.

The circuit constituting the recording head having the above-mentioned structure is integrated by using the driving IC 23 as one unit, and a plurality of the integrated circuits 23 are mounted on the same substrate. That is, the recording density is 16 dots / mm and the recording width is A
4 (about 210 mm) and the driving IC 23 controls ink ejection from 64 ejection ports (64 bits), one print head is equipped with 53 ejection control integrated circuits. .

At this time, the mounting area on the board is made as small as possible,
Further, a control signal such as an image data clock (CLK) input to the recording head is cascade-connected to all the driving ICs 23 in order to simplify wiring on the substrate.

[0008]

However, in the above-mentioned conventional example, since all control signals of a large number of driving ICs are connected in cascade, control is performed by switching characteristics of the driving ICs or wirings between the driving ICs. The pulse width and duty of the signal may change. This amount of change is normally several ns to several tens of ns per driving IC, and can be ignored when the number of driving ICs connected is small or the data transfer rate is slow, but the number of driving ICs connected is small. When there are many cases and when the data transfer rate is high, it becomes a problem that cannot be ignored.

For example, an ink jet type recording head in which a recording density is 16 dots / mm, a recording width is an A3 width (about 297 mm), and one driving IC controls 64 ejection ports (64 bits) is considered. If the drive I is mounted
The number of Cs is about 74, and assuming that the pulse width variation of the control signal is 4 ns per one stage of the driving IC, the pulse width of the driving IC at the final stage varies by about 300 ns at the maximum compared to the input pulse width. Becomes That is, when the pulse width for energizing the electrothermal converter is 3 μs, the first driving I
Energization time of the electrothermal converter driven by C (3 μs)
Then, the energization time (3 μs ± 300 ns) of the electrothermal converter driven by the driving IC at the final stage changes by about 10%.

Such a change may cause unevenness in the density of the recorded image or cause non-ejection of the ink jet, which may significantly impair the quality of the printed image and the reliability of the ink jet print head. If the duty of the data transfer clock is 50% and the pulse width varies by 300 ns, the clock cycle is at least 600.
Since ns (variation width × 2) is required, the maximum value of the transfer clock is suppressed to 1.6 MHz. This is a major obstacle to improving the recording speed.

Therefore, in the conventional recording head, the control signal series supplied from the driver circuit is made into two series to reduce the number of cascade connection stages, and necessary control signals are connected in parallel to each driving IC. Although there are some, the number of input terminals increases and the wiring on the substrate becomes complicated, leading to an increase in the size of the substrate, which impedes miniaturization of the recording head and realization of high-speed recording.

The present invention has been made in view of the above-mentioned conventional example, and an object of the present invention is to provide a recording head which is compact and capable of high-quality and high-speed recording, and a recording apparatus equipped with the recording head.

[0013]

In order to achieve the above object, the recording head of the present invention has the following constitution. That is, a recording head in which a plurality of recording elements are arranged in a predetermined direction, a plurality of electric conductors corresponding to each of the plurality of recording elements, and the plurality of electric conductors are divided into a plurality of groups,
A plurality of driving means for driving the current-carrying body for each of the divided groups to perform a recording operation by the plurality of recording elements, and an image signal from the outside and a recording operation commonly applied to each of the plurality of driving means. Input means for inputting a control signal for controlling to perform the control signal, and the control signal so that the control signal is commonly applied to each of the plurality of driving means as a signal satisfying a predetermined reference over all of the plurality of driving means. And a recording head for adjusting the recording head.

According to another invention, a plurality of recording elements are arranged in a predetermined direction, and a plurality of electric conductors corresponding to each of the plurality of recording elements and the plurality of electric conductors are divided into a plurality of groups. , A plurality of driving means for driving the current-carrying body for each of the divided groups to perform a recording operation by the plurality of recording elements, and an image signal and a recording operation commonly applied to each of the plurality of driving means from the outside. Input means for inputting a control signal for controlling so as to perform the control, and the control signal so that the control signal is commonly applied to each of the plurality of drive means as a signal satisfying a predetermined reference over all of the plurality of drive means. A recording device provided with a recording head, characterized in that it has an adjusting means for adjusting a signal, the conveying means for conveying a recording medium in a predetermined direction, and an image signal from an external device. Input means for inputting, the recording head has a plurality of recording elements arranged over a length corresponding to a recording width of the recording medium, and the recording head is electrically controlled and the conveying means is mechanically controlled. A recording device is provided which records on a recording medium.

[0015]

According to the present invention having the above-described structure, the plurality of driving means are provided with an input control signal which is commonly applied to the plurality of driving means and controls to perform the recording operation. The control signal is adjusted so that it is commonly applied to each means.

According to another aspect of the invention, a plurality of recording elements of the recording head, the control signals of which are adjusted as described above, are arranged over the recording width of the recording medium, and the electric control of the recording head and the machine of the conveying means. Recording on the recording medium is performed by dynamic control.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is an external perspective view showing the configuration of the main part of an ink jet type color printer which is a typical embodiment of the present invention. As shown in FIG. 1, the inkjet type color printer of the present embodiment has a plurality of color inkjets (cyan (C), magenta (M), yellow (Y)) over the entire width of the recording material (continuous sheet) 17. , Black (K)), four recording heads (full multi-type storage heads) 1A, 1B, 1C and 1D are arranged in the recording medium conveyance direction. Cyan (C), magenta (M), yellow (Y), and black (K) inks are ejected onto the recording material 17 at predetermined timings from the ejection ports 13 of the recording heads 1A, 1B, 1C, and 1D, respectively. It is discharged toward.

In the present embodiment, the recording material 17 which is a foldable continuous sheet is driven in the VS direction shown in FIG. 1 by driving the conveying motor under the control of the control circuit described below, and the recording material 17 is recorded. An image is recorded on the material 17. In addition,
In FIG. 1, reference numeral 18 is a sheet feeding roller, 19 is a recording material 17 which is a continuous sheet together with the sheet feeding roller 18.
Is a discharge-side roller that holds the sheet in the recording position and that feeds the sheet 17 in the direction of the arrow VS in conjunction with the sheet feed roller 18 that is driven by the drive motor. Further, the recording heads 1A to 1D have a common configuration.

FIG. 2 is a block diagram showing the configuration of the control circuit of an ink jet type color printer. In FIG. 2, 170 is an interface for inputting a recording signal from an external device such as a host computer, 171 is an MPU, and 172 is an R for storing a control program (including a character font if necessary) executed by the MPU 171.
OM, 173 is a DRA for temporarily storing various data (recording data, recording data supplied to the head, etc.).
It is M. A gate array 174 controls the supply of print data to the print heads 1A to 1D, and also controls data transfer between the interface 170, MPU 171, and RAM 173. A conveyance motor 178 conveys the recording paper (continuous sheet in this embodiment). Reference numeral 175 is a head driver for driving the recording head, and 176 is a motor driver for driving the carry motor 178.

The operation of the control circuit will be briefly described. When a recording signal is input to the interface 170, the gate array 1
The recording signal is converted between the 74 and the MPU 171 into recording data for printing. Then, the motor driver 176
Is driven, and the print heads 1A to 1D are driven in accordance with the print data sent to the head driver 175.
The recording operation is performed.

FIG. 3 is an external perspective view showing the structure of one of the ink jet type full-multi type recording heads 1A to 1D according to the present embodiment, which is cut away. In FIG. 3, reference numeral 11 is a heating resistor that constitutes an electrothermal converter 2 for generating air bubbles due to film boiling in the ink and ejecting the ink by generating heat in response to energization. Are formed through the same manufacturing process as the semiconductor. Reference numeral 13A is a liquid path forming member for forming the discharge port 13 and the liquid path 14 communicating with the discharge port 13 corresponding to the heating resistor 11, and 15 is a top plate. Reference numeral 16 is a common liquid chamber that communicates with each liquid passage 14 in common, and stores ink supplied from an ink supply source (not shown).

FIG. 4 is a block diagram showing a circuit structure of the recording heads 1A to 1D having the mechanical structure shown in FIG. In the configuration shown in FIG. 4, the same components and signals as those shown in the conventional example are designated by the same reference numerals and symbols, and the description thereof will be omitted.

The driving IC 23 mounted on each of the recording heads 1A to 1D of this embodiment uses an image data transfer clock (CL
A shift register 24 for inputting image data (SI) according to K), a latch circuit 25 for collectively holding input image data according to input of a latch signal (LAT), an energization instruction signal (EI) and an energization instruction signal transfer clock (ECK) A flip-flop (F / F) 26 for sequentially energizing the electrothermal converter 21 and an image data transfer clock (C
A correction circuit 31 for correcting the pulse width of LK) and a correction circuit for counting the corrected clock pulses output from the correction circuit 31 and correcting the “ON” time of the pulse width setting signal (ENB). 32 and latch circuit 2
5 output, flip-flop 26 output, and correction circuit 32
It is constituted by an electric conductor driving IC 27 that controls electric conduction to the electrothermal converter 21 according to the output of Then, one driving IC 23 controls a plurality of adjacent electrothermal converters 21. A plurality of drive ICs 23 are mounted on the recording heads 1A to 1D, and all the control signals are cascade-connected to each drive IC 23.

The correction circuit 31 has a reference clock (C
LK0) is included in the clock oscillator, and the correction circuit 31 uses a comparator to incorporate the reference clock (C
LK0) is compared with the input image data transfer clock (CLK), and based on the comparison result, if the pulse width of the image data transfer clock (CLK) is below a predetermined threshold value, the pulse width is corrected. Further, the correction circuit 32 inputs the corrected clock (CLK ′) from the correction circuit 31, counts this clock pulse by the built-in counter, and sets the time width and pulse width corresponding to the counted number of clock pulses. The signal (ENB) is compared with a built-in comparator. Based on the comparison result, the correction circuit 32 corrects the pulse width of the pulse width setting signal (ENB) if the pulse width is below a predetermined threshold. Here, it is assumed that the predetermined threshold value set in each driving IC 23 has a common value and the reference clock (CLK0) has a common frequency.

In this way, the pulse widths of the image data transfer clock (CLK) and the pulse width setting signal (ENB) input to each driving IC 23 are compared with a predetermined threshold value, and which driving IC 23 is always present. Also, in the above, the signal is adjusted so as to satisfy the predetermined standard and have a substantially constant pulse width.

Therefore, according to this embodiment, the pulse width setting signal (ENB) and the pulse width of the image data transfer clock (CLK) are driven inside the recording head without changing the number or type of external control signals. It is possible to make a correction for each driving IC, and it is possible to suppress a change in pulse width that occurs between the driving ICs.

As a result, even if a large number of driving ICs are connected in a cascade to form a full-multi type memory head, the energization time of the electrothermal converter driven by the first driving IC and the driving time of the final stage. There is almost no change between the energization time of the electrothermal converter driven by the IC and the high-quality image recording.

Furthermore, as a result of suppressing the fluctuation of the pulse width of the data transfer clock to be small, the clock cycle can be shortened, that is, the clock frequency can be increased, and the transfer rate of the image data can be increased. this is,
This contributes to the improvement of the recording speed of the entire printer device.

Furthermore, since the number and types of control signals supplied from the outside of the print head do not change, the number of input terminals of the print head does not increase and wiring on the substrate does not become complicated. There is an advantage.

In this embodiment, one of the two correction circuits used in one driving IC has a built-in clock, but the present invention is not limited to this. For example, as shown in FIG. 5, a reference clock generation circuit (CL) is provided inside the driving IC so that a common reference clock can be supplied to the correction circuit 31 and the correction circuit 32.
KGEN) 33 may be provided.

In this embodiment, a printer having a plurality of recording heads according to the number of inks has been described, but the present invention is not limited to this. For example, it goes without saying that the present invention can be applied to a monochrome type printer having one recording head.

The present invention is provided with means (eg, electrothermal converter or laser light) for generating heat energy as energy used for ejecting ink, particularly in the ink jet recording system, and by the heat energy, The printing apparatus of the type that causes a change in the state of ink has been described. According to such a method, the recording density is increased,
High definition can be achieved.

Regarding the typical structure and principle thereof, see, for example, US Pat. Nos. 4,723,129 and 4740.
What is done using the basic principles disclosed in 796 is preferred. This method can be applied to both the so-called on-demand type and continuous type, but especially in the case of the on-demand type, liquid (ink)
By applying at least one drive signal to the electrothermal transducer arranged corresponding to the sheet or liquid path in which the liquid crystal is held, which corresponds to the recorded information and gives a rapid temperature rise exceeding the film boiling. Since heat energy is generated in the electrothermal converter to cause film boiling on the heat acting surface of the recording head, air bubbles in the liquid (ink) corresponding to this drive signal in a one-to-one correspondence can be formed. It is valid. The liquid (ink) is ejected through the ejection openings by the growth and contraction of the bubbles to form at least one droplet. It is more preferable to make this drive signal in a pulse shape, because bubbles can be grown and contracted immediately and appropriately, and thus a liquid (ink) with excellent responsiveness can be achieved.

As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the discharge port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned specifications, The present invention also includes configurations using US Pat. No. 4,558,333 and US Pat. No. 4,459,600, which disclose configurations in which the heat-acting surface is arranged in a bending region. In addition, for multiple electrothermal converters,
Japanese Unexamined Patent Publication No. 59-123670, which discloses a structure in which a common slot is used as a discharge portion of an electrothermal converter, and Japanese Patent Laid-Open No. 59-63, which discloses a structure in which an opening for absorbing a pressure wave of thermal energy is associated with the discharge portion A configuration based on Japanese Patent No. 138461 may be used.

Further, as a full line type recording head having a length corresponding to the width of the maximum recording medium which can be recorded by the recording apparatus, a combination of a plurality of recording heads as disclosed in the above-mentioned specification provides the length. Either of the structure satisfying the requirement or the structure as one recording head integrally formed may be used.

In addition, by being mounted on the apparatus main body, it can be electrically connected to the apparatus main body and can be supplied with ink from the apparatus main body by a replaceable chip type recording head or the recording head itself. Alternatively, a cartridge type recording head provided with an ink tank may be used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc., which are provided as a configuration of the recording apparatus of the present invention, because the effect of the present invention can be further stabilized. . Specific examples thereof include capping means, cleaning means, pressurizing or suctioning means for the recording head, preheating means using an electrothermal converter or another heating element or a combination thereof, and recording. It is also effective to perform a stable recording by performing a preliminary discharge mode in which another discharge is performed.

Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be integrally formed or a plurality of combinations may be used. Alternatively, the device may be provided with at least one of full-color mixed colors.

In the embodiments of the present invention described above, the ink is described as a liquid, but an ink that solidifies at room temperature or lower, or one that softens or liquefies at room temperature may be used, or In the inkjet method, it is common to control the temperature of the ink itself within a range of 30 ° C to 70 ° C to control the temperature of the ink so that the viscosity of the ink is within a stable ejection range. It is sufficient that the ink is liquid.

In addition, in order to positively prevent the temperature rise due to thermal energy from being used as the energy for changing the state of the ink from the solid state to the liquid state,
Alternatively, in order to prevent the ink from evaporating, an ink that solidifies in a standing state and liquefies by heating may be used. In any case, by applying heat energy, such as ink that is liquefied by applying heat energy according to the recording signal and liquid ink is ejected, or that begins to solidify when it reaches the recording medium. The present invention can be applied to the case where an ink having a property of being liquefied for the first time is used. In such a case, the ink is retained as a liquid or solid in the recesses or through holes of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. It may be configured to face the electrothermal converter. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, as a form of the recording apparatus according to the present invention, in addition to the one provided integrally or separately as an image output terminal of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and further transmission / reception It may take the form of a facsimile machine having a function.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0045]

As described above, according to the present invention, the input control signal which is commonly applied to each of the plurality of driving means and controls to perform the recording operation satisfies the predetermined standard over all of the plurality of driving means. Since the control signal is adjusted so as to be commonly applied to each of the plurality of driving means as a signal, it is possible to suppress the fluctuation of the control signal that may occur between the plurality of driving means, and to provide a large number of driving means in the recording head. Even if it is provided, high-speed and high-quality recording can be realized without being affected by the fluctuation of the control signal.

Further, since the control signal fluctuation can be suppressed without receiving a special control signal from the outside,
There is also an advantage that the size of the recording head cannot be increased due to an increase in control signals for the recording head and the outside.

According to another aspect of the invention, a recording head having the above-described effects is used, and a plurality of recording elements of the recording head are arranged so as to be arranged over the recording width of the recording medium, and the recording head is formed. Since the recording on the recording medium is performed by the electrical control and the mechanical control of the conveying means, there is an effect that high-speed and high-quality recording can be performed.

[Brief description of drawings]

FIG. 1 is an external perspective view showing the configuration of the main part of an inkjet type color printer that is a typical embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a control circuit of an inkjet type color printer.

FIG. 3 is an external perspective view showing the structure of one of the inkjet type full multi-type recording heads 1A to 1D by breaking it.

4 is a block diagram showing a circuit configuration of recording heads 1A to 1D having a mechanical configuration as shown in FIG.

FIG. 5 is a block diagram showing another embodiment of the circuit configuration of the recording heads 1A to 1D.

FIG. 6 is a block diagram showing a configuration of a conventional recording head and a driver circuit for driving the recording head.

FIG. 7 is a time chart showing drive timings of the recording head shown in FIG. 6 and its driver circuit.

[Explanation of symbols]

 1A-1D Recording head 21 Electrothermal converter 23 Driving IC 24 Shift register 25 Latch circuit 26 Flip-flop 27 Conductor driving IC 31-32 Correction circuit 33 Reference clock generation circuit 170 Interface 171 MPU 172 ROM 173 DRAM 174 Gate array 175 Head driver 176 Motor driver 178 Conveyor motor

Claims (9)

[Claims] 1. A recording head in which a plurality of recording elements are arranged in a predetermined direction, wherein a plurality of electric conductors corresponding to each of the plurality of recording elements, and the plurality of electric conductors are divided into a plurality of groups, A plurality of driving means for driving the electric conductor for each of the divided groups to perform a recording operation by the plurality of recording elements, and an image signal from the outside and a recording operation commonly applied to each of the plurality of driving means to perform the recording operation. Input means for inputting a control signal for controlling to perform the control signal, and the control signal so that the control signal is commonly applied to each of the plurality of driving means as a signal satisfying a predetermined reference over all of the plurality of driving means. A recording head for adjusting the recording head. 2. The recording head according to claim 1, wherein the recording head is an inkjet recording head that performs recording by ejecting ink. 3. The recording head is a recording head for ejecting ink by utilizing thermal energy, and the current-carrying body is provided with an electrothermal converter for generating thermal energy given to the ink. The recording head according to claim 1, wherein the recording head is a recording head. 4. Each of the plurality of driving means is an integrated electronic circuit, and the electronic circuit temporarily stores an image signal corresponding to the number of electric conductors belonging to each of the plurality of driving means. The recording head according to claim 1, further comprising a register and a latch circuit that latches an image signal stored in the register. 5. The adjusting means includes a clock generating means for generating a clock of a predetermined frequency and a comparing means for comparing the clock of the predetermined frequency with the control signal, and based on a comparison result by the comparing means. The recording head according to claim 1, wherein the pulse width of the control signal is adjusted. 6. The control signal includes an image clock signal for supplying the image signal, and an instruction signal for instructing to energize the energizing body for a predetermined time. Recording head as described. 7. The recording head according to claim 1, wherein the control signal is cascade-connected to each of the plurality of driving units. 8. A recording apparatus including the recording head according to claim 1, further comprising a conveying unit that conveys a recording medium in a predetermined direction, and an input unit that inputs an image signal from an external device. The recording head has a plurality of recording elements arranged over a length corresponding to the recording width of the recording medium, and recording on the recording medium is performed by electrical control of the recording head and mechanical control of the conveying unit. A recording device characterized by. 9. The input means inputs a color image signal, and has the recording heads as many as the number of color components of the color image signal, the number of recording heads having the number of color components is in a conveyance direction of the recording medium. 9. The recording device according to claim 8, wherein the recording device is arranged in a line.