JP2001246751A - Recording head, recording apparatus with the recording head, and method for driving recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To normally record even when the number of recording elements to be simultaneously driven changes without increasing the number of lines for signals to be transmitted to a recording head from a recording apparatus body. SOLUTION: There are provided, on an element base 100, heating units 101, power transistors 102, an AND circuit 113, a latch circuit 103 for latching recording data synchronously with a latch clock Latch, a shift register 104 for holding serial recording data Data inputted from an input terminal 106 synchronously with a serial clock Clock correspondingly to each recording element, a counter circuit 121 for counting the number of simultaneously turned on bits of the recording data, and a heat pulse-generating circuit 122 for generating an optimum heat pulse Heat based on a clock signal 105 with taking the number of simultaneously turned on bits into account.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording head, a recording apparatus provided with the recording head, and a method of driving the recording head, and more particularly to a recording head capable of driving a plurality of recording elements in accordance with recording data, and the recording head. And a method of driving a recording head.

[0002]

2. Description of the Related Art As an information output device in, for example, a word processor, a personal computer, a facsimile, etc., there is a printer for recording desired information such as characters and images on a sheet-like recording medium such as paper or film.

[0003] Various types of printing methods are known for printers. However, ink-jet printing is possible because non-contact printing is possible on printing media such as paper, colorization is easy, and quietness is high. In recent years, the method has attracted special attention. As a configuration, a recording head that ejects ink according to desired recording information is mounted, and recording is performed while reciprocating scanning in a direction perpendicular to the feeding direction of a recording medium such as paper. Are generally widely used because they are inexpensive and easy to miniaturize.

A recording head applied to a thermal ink jet type printer that discharges ink by utilizing foaming energy generated by heating ink among ink jet types has an orifice provided for discharging liquid. A liquid discharge section having a liquid flow path which is a part of a heat acting section communicating with the orifice and discharging liquid droplets, the heat energy acting on the liquid; and a means for generating heat energy. An electrothermal conversion element (heating element) is provided on an element substrate such as a semiconductor substrate.

In recent years, not only a plurality of heating elements but also a driver such as a power transistor for driving each heating element and image data input in series have been provided to each element base of such a recording head. A shift register having the same number of bits as that of the heating element for sending the data in parallel to each other and a latch circuit for temporarily storing data output from the shift register are formed on the same base.

FIG. 5 is a block diagram showing an example of a circuit configuration formed on an element substrate of a conventional recording head.

In FIG. 5, reference numeral 500 denotes an element substrate,
501 is a heating element (resistor) provided corresponding to the printing element (nozzle), and 502 is a power transistor for controlling the energization of each heating element 501. 513, an AND circuit for defining operating conditions of the power transistor 502;
A latch circuit latches recording data in synchronization with a latch signal Latch input from a latch clock input terminal 507. Reference numeral 504 denotes a shift register, which is the recording data D input from the serial data input terminal 506.
data and the serial clock Clock input from the serial clock input terminal 505 in synchronization with the recording data.
Holds data corresponding to the number of recording elements in the recording head.

Reference numerals 508 to 512 denote input / output terminals.
Reference numeral 08 denotes an input terminal for a drive pulse signal (HE) for controlling the ON time of the power transistor 502, that is, the time for driving the heating element 501 by supplying a current from outside the recording head unit, and reference numeral 509 denotes a driving power supply for the logic circuit. (5V) input terminal, 510 is a ground terminal for driving power of the logic circuit, 511 is an input terminal for driving power of the heating element 501, 5
Reference numeral 12 denotes a ground terminal for a heating element driving power supply.

In the circuit having the above configuration, the recording data input from the serial data input terminal 506 is stored in the shift register 504 and held in the latch circuit 503 by the latch signal Latch. In this state, the terminal 50
8, a heat pulse (HE) is input. Where AN
By taking the logical sum of the heat pulse and the print data in the D circuit 513, the transistor 502 corresponding to the print data is turned on for a time corresponding to the width of the heat pulse, and the current flows through the corresponding heating element 501, and the liquid flow The ink in the path is heated and foams, and is discharged as droplets from the nozzle tip.

Here, considering the energy required for foaming the liquid in the heating element 501, if the heat radiation condition is constant, the energy is equal to the energy input to the unit area of the heating element and the energy of the area of the heating element. Expressed by the product. Thereby, the voltage applied to both ends of the heating element 501 and the heating element 50
The current and time (pulse width) flowing through 1 may be set to values at which the required energy can be obtained.

Regarding the voltage applied to the heating elements, the number of heating elements driven at the same time (that is, simultaneously turned on) because of the impedance of the path from the power supply of the printing apparatus main body to the element substrate of the recording head. The number of bits, hereinafter referred to as the number of simultaneous ON bits).

That is, when the number of simultaneous ON bits is small, the current flowing from the recording apparatus main body to the element substrate of the recording head decreases, so that a voltage substantially equal to the power supply voltage is applied. On the other hand, when the number of simultaneous ON bits increases, the current flowing from the recording apparatus main body to the element substrate of the recording head increases, so that the voltage drop due to the impedance between the power supply and the element substrate increases.

In recent thermal ink-jet printers, the size of droplets ejected for high image quality has been reduced, and the number of simultaneous on-bits has tended to increase in order to improve the recording speed. For this reason, the change in the voltage drop due to the change in the number of simultaneous ON bits tends to be further increased.

Here, when the pulse width to be applied is constant, when the number of simultaneous ON bits is large and the voltage drop is large, the value of the current flowing through the heating element becomes small, and the amount of energy supplied to the heating element becomes insufficient. As a result, ink droplets cannot be ejected correctly, or in extreme cases, the quality of an image recorded without ejecting ink is degraded.

On the other hand, if a pulse width that can be ejected correctly even when the number of simultaneous on-bits becomes the maximum is added, excessive energy is supplied to the heating element, which may lead to burning of the heating element and shortening of the service life. There is.

As a method for coping with this, the number of simultaneous ON bits is monitored on the recording apparatus side, and the heat pulse width is changed according to the number of simultaneous ON bits. A method for applying a substantially constant energy has been proposed.

[0017]

The method of changing the heat pulse width according to the change in the number of simultaneous ON bits can be implemented by outputting a heat signal with the changed pulse width on the recording apparatus main body side.

However, since the recording head for performing color recording is provided with element bases by the number of inks to be used, the control for changing the pulse width is performed separately on each element base. Heat signal needs to be added. This leads to an increase in the number of signals transmitted from the printing apparatus main body to the printing head, and an increase in the number of pads used for connection between the two, and complicated control on the printing apparatus side. This problem becomes more pronounced when two types of dark and light inks are used for each color in order to increase the number of gradations of the recorded image.

The present invention has been made in view of the above situation, and the number of simultaneously driven recording elements is changed without increasing the number of signal lines transmitted from the recording apparatus main body to the recording head. It is an object of the present invention to provide a recording head capable of performing normal recording even when recording, a recording apparatus including the recording head, and a method of driving the recording head.

[0020]

In order to achieve the above object, a recording head according to the present invention comprises a plurality of recording elements, a plurality of driving elements for driving the corresponding recording elements, and image data to be recorded. Holding means for holding, counting means for counting the number of printing elements to be driven simultaneously from the image data, and a drive signal for generating a drive signal to be supplied to the drive element according to the number of printing elements to be driven simultaneously A driving unit that drives a driving element corresponding to the image data held by the holding unit in accordance with the drive signal.

[0021] The above object is also achieved by a recording apparatus having the recording head.

According to another aspect of the present invention, there is provided a method of driving a recording head, comprising: a plurality of recording elements; a plurality of driving elements each for driving a corresponding recording element; Means for counting the number of printing elements to be driven simultaneously from the image data, and supplying the driving elements to the driving elements according to the number of printing elements to be driven simultaneously. And a drive control step of driving a drive element corresponding to the image data held by the holding unit in accordance with the drive signal.

That is, in a recording head including a plurality of recording elements, a plurality of driving elements for driving the corresponding recording elements, and a holding unit for holding image data to be recorded, the recording head is driven simultaneously from the image data. The number of print elements to be counted is counted, a drive signal to be supplied to the drive elements is generated according to the number of print elements to be simultaneously driven, and the drive elements corresponding to the image data held by the holding unit are driven according to the drive signals. .

With this arrangement, it is possible to appropriately drive each printing element even if the number of printing elements driven simultaneously changes without increasing the number of signal lines transmitted from the printing apparatus main body to the printing head. Therefore, it is possible to always perform recording that sufficiently exhibits the original performance of the recording apparatus.

Further, in a printing apparatus using such a printing head, processing on the printing apparatus main body side can be reduced.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

In this specification, the term “record” (also referred to as “print”) refers not only to the formation of significant information such as characters and figures, but also to the fact that humans are visually or irrelevant. Regardless of whether or not the image has been exposed so as to be perceivable, a case where an image, a pattern, a pattern, or the like is widely formed on a recording medium or a medium is processed is also referred to.

Here, the "recording medium" is not limited to paper used in a general recording apparatus, but is widely used for cloth, plastic film, metal plate, glass, ceramics, wood,
A material that can accept ink, such as leather, is also referred to.

Further, “ink” (sometimes referred to as “liquid”) is to be interpreted broadly as in the definition of “recording (printing)”, and by being applied on a recording medium, It refers to a liquid that can be used for forming an image, a pattern, a pattern, or the like, processing a recording medium, or processing ink (for example, solidifying or insolubilizing a colorant in ink applied to the recording medium).

Further, the term "element substrate" used below does not indicate a simple substrate made of a silicon semiconductor but a substrate provided with each element, wiring, and the like.

Further, the expression "on the element substrate" used in the following description indicates not only the upper side of the element substrate but also the surface of the element substrate and the inside of the element substrate near the surface. The term "built-in" as used in the present invention is not a term indicating that each element is simply disposed on a substrate, but is a step of manufacturing a semiconductor circuit. This indicates that the device is integrally formed and manufactured on an element substrate by, for example, the method described above.

First, a typical overall configuration and a control configuration of a recording apparatus using the recording head of the present invention described below will be described.

<Schematic Description of Apparatus Main Body> FIG. 6 shows an ink jet printer IJ which is a typical embodiment of the present invention.
It is an external appearance perspective view showing the outline of composition of RA. In FIG. 6, the carriage HC that engages with the spiral groove 5004 of the lead screw 5005 that rotates via the driving force transmission gears 5009 to 5011 in conjunction with the forward / reverse rotation of the drive motor 5013 has pins (not shown). Guide rail 50
03 reciprocates in the directions of arrows a and b. The carriage HC includes a recording head IJH and an ink tank IT.
Integrated inkjet cartridge IJC
Is installed.

Reference numeral 5002 denotes a paper holding plate, which is a carriage H
The recording paper P is pressed against the platen 5000 over the moving direction of C. Reference numerals 5007 and 5008 denote photocouplers, which are home position detectors for confirming the presence of the carriage lever 5006 in this region and switching the rotation direction of the motor 5013.

Reference numeral 5016 denotes a member for supporting a cap member 5022 for capping the front surface of the recording head IJH.
Reference numeral 15 denotes a suction device that suctions the inside of the cap, and performs suction recovery of the recording head through the opening 5023 in the cap. 5
Reference numeral 017 denotes a cleaning blade. Reference numeral 5019 denotes a member which allows the blade to move in the front-rear direction. These members are supported by a main body support plate 5018. It goes without saying that the blade is not limited to this form and a known cleaning blade can be applied to this example.

Reference numeral 5021 denotes a lever for starting suction for recovery from suction, and a cam 5020 which engages with the carriage.
The driving force from the driving motor is controlled by a known transmission mechanism such as clutch switching.

The capping, cleaning, and suction recovery are configured so that desired processing can be performed at the corresponding position by the action of the lead screw 5005 when the carriage comes to the area on the home position side. If a desired operation is performed at the timing, any of the embodiments can be applied.

<Description of Control Structure> Next, a control structure for executing the recording control of the above-described apparatus will be described.

FIG. 7 is a block diagram showing a configuration of a control circuit of the ink jet printer IJRA. In the figure showing a control circuit, 1700 is an interface for inputting a recording signal, 1701 is an MPU, 1702 is an MPU 17
ROM for storing a control program executed by 01, 17
Numeral 03 denotes a DRAM for storing various data (such as the recording signal and recording data supplied to the head). 170
Reference numeral 4 denotes a gate array (GA) that controls supply of print data to the print head IJH, and also controls data transfer between the interface 1700, the MPU 1701, and the RAM 1703. Reference numeral 1710 denotes a carrier motor for transporting the recording head IJH, and reference numeral 1709 denotes a transport motor for transporting the recording paper. Reference numeral 1705 denotes a head driver for driving the recording head, and reference numerals 1706 and 1707 denote motor drivers for driving the transport motor 1709 and the carrier motor 1710, respectively.

The operation of the above control configuration will be described. When a recording signal enters the interface 1700, the gate array 1
The recording signal is converted into recording data for printing between the 704 and the MPU 1701. And the motor driver 1
The printheads 706 and 1707 are driven, and the printhead is driven according to the print data sent to the head driver 1705 to perform printing.

Although the control program executed by the MPU 1701 is stored in the ROM 1702 here,
An erasable / writable storage medium such as an EEPROM may be further added so that the host computer connected to the inkjet printer IJRA can change the control program.

<Explanation of Ink Cartridge> As described above, the ink tank IT and the recording head IJH are integrally formed and are exchangeable ink cartridge IJC.
However, the ink tank IT and the recording head IJH may be configured to be separable so that only the ink tank IT can be replaced when the ink runs out.

FIG. 8 is an external perspective view showing the structure of an ink cartridge IJC in which the ink tank and the head can be separated. As shown in FIG. 8, the ink cartridge IJC holds the ink tank IT and the recording head I at the position of the boundary line K.
JH can be separated. When the ink cartridge IJC is mounted on the carriage HC, the ink cartridge IJC is provided with an electrode (not shown) for receiving an electric signal supplied from the carriage HC side. Is driven to eject ink.

In FIG. 8, reference numeral 500 denotes an ink ejection port array. The ink tank IT is provided with a fibrous or porous ink absorber for holding ink.

Hereinafter, embodiments of the recording head of the present invention used in the above-described recording apparatus will be described.

[First Embodiment] FIG. 1 is a block diagram showing a circuit configuration of a first embodiment of a recording head according to the present invention.

In FIG. 1, reference numeral 100 denotes an element substrate.
Reference numeral 101 denotes a heating element that functions as an electrothermal conversion element such as a resistor. Reference numeral 102 denotes a power transistor that controls energization of the heating element 101. 113 is the power transistor 102
AND circuit for defining the operating conditions of the input terminal 1
07 is a latch circuit that latches recording data in synchronization with a latch clock Latch input from the latch circuit 07. 104
Is a shift register, which is synchronized with the serial clock Clock input from the input terminal 105 and has an input terminal 1
The serial print data Data input from step 06 is held for each print element.

Reference numerals 109 to 112 denote power supply terminals.
9 is an input terminal for a drive power supply VDD of the logic circuit, 11
Reference numeral 0 denotes a ground terminal VSS for a logic circuit, 111 denotes an input terminal of a driving power supply VH of the heating element 101, and 112 denotes a ground terminal GND for a heating element driving power supply.

In this embodiment, in addition to the above, in consideration of the counter circuit 121 for counting the number of simultaneous ON bits and the number of simultaneous ON bits counted by the counter 121, an optimum heat pulse Heat based on the clock signal 105 is used. Is generated.

FIG. 2 is a timing chart showing the state of each signal of the circuit of FIG.
In this example, the number of recording elements provided in the memory is 16 and the shift register 104 and the latch circuit 103 correspond to 16 bits. Hereinafter, the operation of the present embodiment will be described with reference to FIG.

The recording data Data input from the input terminal 106 is in a state (High / Lo) at the rising edge of the clock every time the clock signal Clock is input.
Data indicating presence / absence is sequentially input to the shift register 104 bit by bit in accordance with w). Shift register 1
When the latch signal Latch is input after the number of bits (16) of the shift register has been input to 04, these data are transferred to the latch circuit 103 and temporarily stored and held. Then, the data held in the latch circuit 103 is input to the AND circuit 113.

On the other hand, the recording data Data, the clock signal Clock, and the latch signal Latch are On Bi.
The t-counter 121 also receives the latch signal Latch.
Is counted (the number of simultaneous ON bits) of the recording data Data input in the period of (1), and is output to the HE generation circuit 122. The HE generation circuit 122 determines the width of the heat pulse Heat corresponding to the number of simultaneous ON bits with reference to a table stored in advance.

Here, the width of the heat pulse is defined by the difference between the rising point and the falling point. In the present embodiment, the rising timing is synchronized with the rising of the latch signal Latch, and the falling timing is synchronized with the rising of the clock signal Clock. That is, in the HE generation circuit 122, the heat pulse Heat pulse is synchronized with the rising edge of the clock pulse by referring to the number of simultaneous ON bits.
Is switched from “High” to “Low”.

Then, the logical sum of the output from the latch circuit 103 and the heat pulse Heat is calculated in the AND circuit 113, and the power transistor 102 corresponding to the recording data Data is driven for a time defined by the width of the heat pulse Heat. Is done. As a result, a current flows through the heating elements 101 connected in series, the ink is heated and foamed, and ink droplets are ejected from the corresponding nozzles to perform printing.

As described above, according to the present embodiment,
The width of the heat pulse can be changed according to the number of simultaneous ON bits without increasing the number of signal lines from the printing apparatus main body to the print head. Thus, normal printing can be performed even if the number of printing elements driven simultaneously changes.

Further, in the recording apparatus using the recording head of the present embodiment, the processing on the recording apparatus main body side can be reduced.

[Second Embodiment] A second embodiment of the recording head according to the present invention will be described below. In the first embodiment, the clock signal Clock used for inputting print data is used to define the width of the heat pulse.
This embodiment uses a dedicated clock pulse to define the width of the heat pulse.

In the configuration in which the clock signal for data input is used to define the width of the heat pulse as in the first embodiment, when the frequency of the clock signal that defines the data transfer rate is low, the heat pulse width In some cases, the unit (resolution) for changing the pulse width becomes large, and an appropriate pulse width cannot be set. Conversely, when the frequency of the data transfer clock is high, the change range of the heat pulse width is within the data transfer time during which the clock pulse is input. In some cases, an appropriate pulse width cannot be set.

In view of the above points, the present embodiment is configured so that the resolution and change range of the heat pulse width can be arbitrarily set, and a dedicated clock pulse Hclock for defining the heat pulse is used. The data is supplied from the recording apparatus main body to the element substrate separately from the clock for data transfer.

FIG. 3 is a block diagram showing the circuit configuration of this embodiment. In the present embodiment, similarly to the first embodiment, a heating element 301, a power transistor 302, an AND circuit 313, a latch circuit 303,
It has a shift register 304, a counter circuit 321, and a heat pulse generation circuit 322.

In this embodiment, the input terminals are the first terminals.
Similarly to the embodiment, the input terminal 309 for the drive power supply VDD of the logic circuit and the ground terminal VSS3 for the logic circuit are provided.
10, an input terminal 311 of a driving power supply VH of the heating element 301,
And a ground terminal GND 312 for a heating element drive power supply, and in addition to this, a dedicated terminal 313 for inputting a clock pulse Hclock for defining a heat pulse.

In such a configuration, the resolution and change range of the heat pulse width can be arbitrarily set according to the value of the frequency of the Hclock supplied from the recording apparatus main body.

FIG. 4 is a timing chart showing the state of each signal of the circuit of FIG.
In this example, the number of recording elements provided in the memory is 16 and the shift register 304 and the latch circuit 303 correspond to 16 bits. Hereinafter, the operation of the present embodiment will be described with reference to FIG.

The recording data Data input from the input terminal 306 is in the state (High / Lo) at the rising edge of the clock every time the clock signal Clock is input.
Data indicating presence / absence is sequentially input to the shift register 304 bit by bit corresponding to w). Shift register 3
When the latch signal Latch is input after the number of bits of the shift register (16) has been input to 04, these data are transferred to the latch circuit 303 and temporarily stored and held. Then, the data held in the latch circuit 303 is input to the AND circuit 313.

On the other hand, the recording data Data, the clock signal Clock, and the latch signal Latch are On Bi.
t counter 321 and the latch signal Latch
Is counted (the number of simultaneous ON bits) of the recording data Data input within the period of (1), and is output to the HE generation circuit 322. The HE generation circuit 322 determines the width of the heat pulse Heat corresponding to the number of simultaneous ON bits with reference to a table stored in advance.

Here, the width of the heat pulse is defined by the difference between the rising point and the falling point. In the present embodiment, the rising timing is synchronized with the rising of the Hclock after a predetermined time has elapsed from the rising of the latch signal Latch, and the falling timing is set after the state of the heat pulse Heat is switched from “Low” to “High”. , A predetermined number of Hclock
It is synchronized with the rise of Hclock after counting k. That is, in the HE generation circuit 322, the heat pulse Hea
After switching the state of t from “Low” to “High”, the state of the heat pulse Heat is changed from “High” to “Low” in synchronization with the number of rising edges of Hclock.
w ".

Then, the logical sum of the output from the latch circuit 303 and the heat pulse Heat is calculated in the AND circuit 313, and the power transistor 302 corresponding to the recording data Data is driven for the time defined by the width of the heat pulse Heat. Is done. As a result, a current flows through the heating elements 301 connected in series, the ink is heated and foams, and ink droplets are ejected from the corresponding nozzles to perform printing.

As described above, according to the present embodiment,
In addition to the effects of the first embodiment, the resolution and change range of the heat pulse width can be arbitrarily set according to the frequency of the signal supplied from the recording apparatus main body.

[Other Embodiments] The embodiments of the present invention have been described above with reference to an ink jet type recording head using an electrothermal transducer and a recording apparatus using the recording head. , Thermal recording method,
The present invention can be applied to a recording head using a method using a piezoelectric element or a method using an LED element array) and a recording apparatus using the recording head, and the same effects can be obtained.

In the description of the first and second embodiments, the logic of all signals is positive.
The logic of each signal is not limited to that shown here, and it goes without saying that any one, a plurality, or all of the signals may be set to negative logic.

In the above embodiment, the rise of the heat pulse is synchronized with the rise of the latch signal. However, another signal may be supplied to define the rise of the heat pulse using the signal. Is possible,
Further, the signal can be used together with a signal for operating another circuit.

The above-described embodiment is particularly provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for ejecting ink even in an ink jet recording system. By using a method in which a change in the state of the ink is caused by energy, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method can be applied to both the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, liquid (ink)
By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding the nucleate boiling to an electrothermal transducer arranged corresponding to the sheet or the liquid path holding the Since thermal energy is generated in the electrothermal transducer and film boiling occurs on the heat-acting surface of the recording head, bubbles in the liquid (ink) corresponding to this drive signal on a one-to-one basis can be formed. It is valid.

The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable.

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

As the configuration of the recording head, in addition to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, The configurations described in U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, which disclose a configuration in which the heat acting surface is arranged in a bending region, are also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 59-123670 discloses a configuration in which a common slot is used as a discharge portion of an electrothermal transducer for a plurality of electrothermal transducers, or an opening for absorbing a pressure wave of thermal energy is discharged. A configuration based on JP-A-59-138461, which discloses a configuration corresponding to each unit, may be adopted.

Further, as a full line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, the length is determined by a combination of a plurality of recording heads as disclosed in the above specification. This may be either a configuration satisfying the above requirements or a configuration as a single recording head formed integrally.

In addition to the cartridge-type recording head in which the ink tank is provided integrally with the recording head itself described in the above embodiment, the recording head is electrically connected to the apparatus main body by being mounted on the apparatus main body. A replaceable chip-type recording head, which enables a simple connection and supply of ink from the apparatus main body, may be used.

Further, it is preferable to add recovery means for the printhead, preliminary auxiliary means, and the like to the configuration of the printing apparatus described above because the printing operation can be further stabilized. Specific examples thereof include capping means for the recording head, cleaning means, pressurizing or suction means, preheating means using an electrothermal transducer or another heating element or a combination thereof. It is also effective to provide a preliminary ejection mode for performing ejection that is different from printing, in order to perform stable printing.

Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but may be an integral recording head or a combination of a plurality of recording heads. Alternatively, the apparatus may be provided with at least one of full colors by color mixture.

In the above-described embodiment, the description has been made on the assumption that the ink is a liquid. However, even if the ink solidifies at room temperature or lower, the ink that softens or liquefies at room temperature is used. Or, in the ink jet method, generally, the temperature of the ink itself is controlled within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range.
It is sufficient that the ink is in a liquid state when the use recording signal is applied.

In addition, in order to positively prevent temperature rise due to thermal energy as energy for changing the state of the ink from the solid state to the liquid state, the temperature can be positively prevented.
Alternatively, in order to prevent evaporation of the ink, an ink which solidifies in a standing state and liquefies by heating may be used. In any case, the application of heat energy causes the ink to be liquefied by application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start to solidify when reaching the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used.

In such a case, the ink is disclosed in JP-A-54-5
No. 6,847, or Japanese Patent Application Laid-Open No. 60-71260, in which the porous sheet is opposed to the electrothermal converter while being held as a liquid or solid substance in the concave portion or through hole of the porous sheet. It may be. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

The present invention can be applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), but can be applied to a single device (for example, a copier, a facsimile). Device).

Further, an object of the present invention is to supply a storage medium (or a recording medium) on which a program code of software for realizing the functions of the above-described embodiments is recorded to a system or an apparatus, and to provide a computer (a computer) of the system or the apparatus. It is needless to say that the present invention can also be achieved by a CPU or an MPU) reading and executing the program code stored in the storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. Also,
When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also the operating system (OS) running on the computer based on the instructions of the program code.
It goes without saying that a case where the functions of the above-described embodiments are implemented by performing some or all of the actual processing, and the processing performs the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the program code is read based on the instruction of the program code. Needless to say, the CPU included in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

When the present invention is applied to the storage medium, the storage medium stores program codes corresponding to the above-described timing chart (shown in FIG. 2 and / or FIG. 4).

[0088]

As described above, according to the present invention, even if the number of recording elements driven simultaneously changes without increasing the number of signal lines transmitted from the recording apparatus main body to the recording head. Since the recording element can be appropriately driven, recording can always be performed while sufficiently exhibiting the original performance of the recording apparatus.

In a recording apparatus using such a recording head, processing on the recording apparatus main body side can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a circuit configuration of a first embodiment of a recording head according to the invention.

FIG. 2 is a timing chart showing the state of each signal when the circuit of FIG. 1 operates.

FIG. 3 is a block diagram illustrating a circuit configuration of a recording head according to a second embodiment of the present invention.

FIG. 4 is a timing chart showing the state of each signal when the circuit of FIG. 3 operates.

FIG. 5 is a block diagram illustrating a circuit configuration example of a conventional recording head.

FIG. 6 is a diagram illustrating an appearance of a printer as an embodiment of a recording apparatus using the recording head according to the invention.

FIG. 7 is a block diagram illustrating a control configuration of the printer of FIG. 6;

FIG. 8 is a diagram showing an ink jet cartridge of the printer of FIG.

[Explanation of symbols]

 100, 300 Element substrate 101, 301 Heating element 102, 302 Power transistor 103, 303 Latch circuit 104, 304 Shift register 121, 321 Counter 122, 322 Heat pulse generation circuit

Claims (15)

[Claims] 1. A plurality of printing elements, a plurality of driving elements each driving a corresponding printing element, holding means for holding image data to be printed, and the number of printing elements to be driven simultaneously from the image data Counting means for counting the number of printing elements to be driven simultaneously, driving signal generating means for generating a driving signal to be supplied to the driving elements according to the number of printing elements to be driven simultaneously, and driving elements corresponding to the image data held by the holding means. And a drive control means for driving according to the drive signal. 2. The printhead according to claim 1, wherein the drive signal generating means changes a pulse width of the drive signal according to the number of print elements to be driven simultaneously. 3. The driving signal generating means according to claim 2, further comprising a table for associating the number of recording elements to be simultaneously driven with a pulse width of the generated driving signal.
A recording head according to claim 1. 4. A shift register for serially inputting the image data in synchronization with a predetermined clock signal and sequentially shifting the input image data in accordance with the clock signal and storing as many shift registers as the number of recording elements. The recording head according to claim 1, wherein: 5. The recording head according to claim 4, wherein the drive signal generating means sets the rise and fall of the pulse width of the drive signal based on the clock signal. 6. The driving signal generating means sets rising and falling edges of a pulse width of the driving signal with reference to a unique clock signal.
A recording head according to claim 1. 7. The device according to claim 1, wherein said recording element, said driving means, said holding means, said counting means, said driving signal generating means, and said driving control means are formed on the same element base. 7. The recording head according to any one of 1 to 6. 8. The recording head according to claim 1, wherein the recording element includes an electrothermal conversion element. 9. The recording head according to claim 1, wherein the recording head is an ink jet recording head that ejects ink droplets from each recording element. 10. A recording apparatus which performs recording using the recording head according to claim 1. 11. A method for driving a recording head, comprising: a plurality of printing elements; a plurality of driving elements each for driving a corresponding printing element; and holding means for holding image data to be printed. A counting step of counting the number of printing elements to be driven simultaneously from image data; a driving signal generating step of generating a driving signal to be supplied to the driving element according to the number of printing elements to be driven simultaneously; And a drive control step of driving a drive element corresponding to the image data held by the drive signal according to the drive signal. 12. The printhead driving method according to claim 11, wherein said drive signal generating step changes a pulse width of a drive signal according to the number of print elements to be driven simultaneously. 13. The recording head according to claim 12, wherein in the driving signal generating step, the number of the recording elements to be driven simultaneously and the pulse width of the generated driving signal are associated with reference to a table. Drive method. 14. The image signal is serially input in synchronization with a predetermined clock signal, and the driving signal generating step sets rising and falling edges of a pulse width of the driving signal with reference to the clock signal. 14. The method of driving a recording head according to claim 11, wherein: 15. The drive signal generating step according to claim 11, wherein the rise and fall of the pulse width of the drive signal are set on the basis of a unique clock signal. Driving method of recording head.