JP3387749B2 - Recording head and recording apparatus using the recording head - Google Patents

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 using the recording head, and more particularly to an inkjet type recording head for recording by ejecting ink and a recording apparatus using the recording head.

[0002]

2. Description of the Related Art An ink jet recording method in which ink is ejected and ejected from a minute ejection port to perform recording is capable of reducing noise generated during recording to a negligible level, and only capable of high speed recording. In addition, there are many advantages such as fixing and recording on so-called plain paper without requiring special processing.

Several methods have been proposed so far for carrying out ink jet recording. Among them, for example, Japanese Patent Laid-Open No. 54-51837 or German Patent Publication (DOS) No. 2843064 has been proposed. The recording method described has a feature different from other inkjet recording methods in that an action force for ejecting ink is obtained by causing thermal energy to act on a liquid (ink).

According to the recording methods disclosed in these publications, the liquid subjected to the action of thermal energy causes a state change accompanied by a sharp increase in volume, and the action force resulting from this state change causes the tip of the recording head to change. Liquid is ejected from an orifice (ejection port) provided in the recording medium to form flying droplets, and the droplets adhere to the recording medium to perform recording. In particular, the inkjet recording method disclosed in DOLS 2843064 can be applied not only very effectively to the so-called drop-on-demand method, but also by arranging a large number of ejection openings in a line, the entire width of the recording paper can be obtained. Since it is possible to easily realize a full-line type recording head configured to have a corresponding recording width and further increase the discharge port density, it is possible to record a high-resolution and high-quality image at high speed. it can.

In the ink jet recording head to which such a recording method is applied, an ejection port provided mainly for ejecting a liquid droplet and a liquid flow path communicating with this ejection port,
Electrothermal converter (heating element) for generating thermal energy
And a substrate provided with. The liquid flow path has a thermal action part, which is a part where thermal energy for ejecting droplets acts on the liquid, as a part of the configuration.

Since the printhead is usually provided with a plurality of ejection ports, a plurality of heating elements are arranged in a line on the substrate for the printhead. In addition to a plurality of heating elements arranged in a line, a driver for driving the heating elements in a one-to-one correspondence with the heating elements in accordance with image data is serially input to such a substrate. A shift register for outputting image data to each driver in parallel and a latch circuit for temporarily storing the output from the shift register are also mounted. Here, the shift register stores image data having the same number of bits as the number of heating elements. A substrate for a recording head in which these circuits are incorporated on the same substrate is, for example, a silicon substrate, and an IC (integrated circuit) having a Bi-CMOS configuration (a configuration in which bipolar transistors and CMOS transistors are mixed) is monolithically formed on the substrate. It is manufactured by forming a heating element as a heating portion.

FIG. 6 is a diagram showing an internal equivalent circuit of a logic circuit mounted on a recording head substrate having 64 heating elements (heating elements). These 64 heating elements (heating elements) are arranged in a line on the substrate.

This substrate, as shown in FIG.
64 heating elements arranged in a line (heating element: H1,
H2, ..., H64) 101, one for each heating element 101
A power transistor 102 that is a driver is provided so as to correspond to the pair 1. One end of each heating element 101 is commonly connected to a heating element driving power supply terminal 110,
The other end is connected to the collector of the corresponding power transistor 102. Power transistor 102
The emitters of are commonly connected to the common terminal 111.

The on-time of each power transistor 102 is controlled according to the pulse signal input to the heat pulse width input terminal 107. Image data (DATA) from the outside is serially input bit by bit (for example, b1, b2, ..., b64) to the shift register 104, and the latch circuit 11 is provided on the output side of the shift register 104.
7 is provided. The clock input terminal 105 and the data input terminal 106 are connected to the shift register 104,
Clock (CLK) input to the clock input terminal 105
The shift operation is executed according to. Further, a power supply terminal 108 for supplying power to a logic circuit portion represented by the shift register 104, the latch circuit 117, etc. on the substrate.
And a ground terminal (GND) 109. The above are the minimum required components for the logic circuit of the printhead.

By the way, in the ink jet recording head, by reducing the number of ejection ports for ejecting ink at the same time, refilling (refilling) of ink from the ink tank to the liquid flow path is properly performed, and deterioration of recording quality is prevented. It is known that high quality recording becomes possible. Therefore, the print head is divided into several blocks (8 blocks in the example shown in FIG. 4), and the logic circuit is designed in consideration that adjacent ejection ports do not eject ink at the same time. ing.

Therefore, the input terminal 114 to which the 3-bit block selection signals (B2, B1, B0) are input in parallel.
To 116, a 3 → 8 decoder 118 for decoding the block selection signal input to the input terminals 114 to 116 into a signal for each block, an odd-numbered element selection signal (hereinafter, ODD signal) and an even-numbered element selection signal (Hereafter, E
Input terminals 112 and 1 to which the VEN signal) is input, respectively.
13 and an AND circuit 119 corresponding to each power transistor 102, 64 power transistors are divided into 8 blocks of 8 power transistors each, and further adjacent power transistors, that is, odd-numbered elements (H1, H
3, ..., H63) and even-numbered elements (H2, H4, ..., H)
64) and 64 are driven separately, and a maximum of four power transistors are simultaneously driven.

Each AND circuit 119 is of a 4-input type, and the signals (BLK1, BLK2, ..., BL) output from the 3 → 8 decoder 118 for the corresponding block are provided.
K8), the pulse signal (ENB) input to the heat pulse width input terminal 107, the even-odd number element selection signal (ODD or EVEN), and the output signal of the latch circuit 117, and the corresponding power transistor 102 is turned on. To drive.

For example, the block selection signal B2 (MSB) is input to the input terminal 114, the block selection signal B1 is input to the input terminal 115, and the block selection signal B0 (L is input to the input signal 116.
SB) is input and B2 = B1 = B0 = 0, then 3
→ 8 The output signal BLK1 from the decoder 118 is turned on to select the heating elements H1, H2, ..., H8, and
When the ODD signal is input from the input terminal 112, the odd numbered heating elements H1, H3, H5, and H7 are selected.

The substrate is a power transistor 1
02 is formed by a bipolar process, and includes a logic circuit portion (shift register 104, latch circuit 117, 3 → 8).
The decoder 118, the AND circuit 119, etc.) are formed by a CMOS process.

In the recording apparatus using the recording head having such a structure, the image data (DATA) is input to the data input terminal 1.
The data is serially input to the shift register 104 via 06, these image data are temporarily stored in the shift register 104 and converted into parallel data, and the parallel data is latched by the latch circuit 117. The output of the latch circuit 117, the output signals (BLK1 to BLK8) from the 3 → 8 decoder 118, the odd-numbered element selection signal (ODD) or the even-numbered element selection signal (EVEN),
AND circuit 1 with the logical product of the heat pulse signal (ENB)
19, the power transistor 102 is turned on only when the output of the AND circuit 119 is turned on, and the heating element 1 is turned on.
01 is driven. As a result, the driven heating element 101
The ink in the liquid flow path corresponding to is heated and the ink is ejected from the ejection port to perform recording.

In addition to the above structure, in order to perform stable ink ejection, a heat retaining heater 121 for controlling the ink temperature is provided, and a rank heater 123 for monitoring the resistance value of the heating element is provided. The drive voltage and drive pulse width can be controlled with respect to variations in resistance. Then, one ends of the heat retaining heater 121 and the rank heater 123 are connected to the common terminal 111, and the other ends thereof are connected to the heat retaining heater terminal 122 and the rank heater terminal 120.

[0017]

However, in the above-mentioned conventional example, the warming heater terminal of the warming heater for controlling the temperature of the ink and the rank heater terminal of the rank heater for monitoring the resistance of the heating element are independently provided. So especially
In a recording head or a full-line type recording head configured by combining a plurality of circuit boards as described above, the number of terminals is increased by the number of combinations, which increases the production cost of the recording head as a whole or increases the recording device and recording device. There is a problem that the cable connecting to the head becomes thick and large.

The present invention has been made in view of the above conventional example, and an object of the present invention is to provide a recording head having a reduced number of terminals and a recording apparatus using the recording head.

[0019]

In order to achieve the above object, the recording head of the present invention has the following constitution.

That is, a heating element, a drive circuit for driving the heating element, a shift register for inputting and temporarily storing image data, and a latch circuit for latching the image data stored in the shift register are provided. A recording head mounted on one substrate, further comprising: a monitor element for monitoring the resistance of the heating element by causing a current to flow on the substrate; a preliminary heater used for head temperature adjustment; and the monitor element. And a common terminal for inputting a signal to the preliminary heater,
The auxiliary heater is connected to the drain side, and the auxiliary heater is connected to the gate side.
The monitor element in which a monitor element and the common terminal are connected.
NMO for controlling child monitor and driving of the preliminary heater
An S-transistor, and a current is applied to the common terminal.
The monitor element is monitored by
By changing the voltage applied to the auxiliary heater,
The recording head is characterized in that the heating temperature of the head changes .

According to another aspect of the present invention, there is provided a recording apparatus using the recording head having the above structure, wherein a monitor means for monitoring the resistance of the monitor element by applying a current to the common terminal, and the common terminal. And a voltage control unit that controls to change the voltage input to the recording apparatus.

[0022]

The recording head may be an ink jet recording head which ejects ink for recording, or is a recording head which ejects ink by utilizing thermal energy and generates thermal energy applied to the ink. A heat energy converter for the above may be provided.

Further, a plurality of substrates may be combined to include many recording elements.

On the other hand, the voltage control means included in the recording apparatus having the above-mentioned structure operates by changing the voltage and adjusting the temperature of the recording head.

[0026]

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

<Schematic Description of Apparatus Main Body> FIG. 1 shows an ink jet printer IJ as a typical embodiment of the present invention.
It is an external appearance perspective view which shows the outline of a structure of RA.

In FIG. 1, a carriage 16 is equipped with an integrated ink jet cartridge IJC having a recording head IJH and an ink tank IT. The recording head IJH is provided with a nozzle group that ejects ink in opposition to the recording surface of the recording paper conveyed to the platen 24. The carriage 16 holds the inkjet cartridge IJC 20, is connected to a part of the drive belt 18 that transmits the driving force of the drive motor 17, and is slidable with two guide shafts 19A and 19B arranged in parallel with each other. It is possible to reciprocate over the entire width of the recording paper.

A head recovery device 26 is provided at one end of the reciprocating path of the carriage 16, for example, at a position facing the carriage 16 at the home position. Then, the head recovery device 26 is operated by the driving force of the motor 22 via the transmission mechanism 23, and the recording head IJH
The capping of the nozzle group is performed. Head recovery device 26
In association with the capping of the recording head IJH by the cap portion 26A of the recording head IJH, ink is sucked by a suction device provided in the head recovery device 26, or from the ink tank IT in the inkjet cartridge IJC to the recording head IJH.
A recovery process for removing the thickened ink in the nozzle is performed by forcibly discharging the ink from the ejection port by pressurizing the ink by a pressurizer provided in the ink supply path to the nozzle. At the end of recording, the recording head IJH is moved to the home position and its nozzle is capped to protect the recording head.

Further, on the side surface of the head recovery device 26, a blade 30 made of silicon rubber, which plays a role of wiping the ink ejection port of the recording head, is provided.
The blade 30 is held by the blade holding member 30A in the form of a cantilever.
2 and the transmission mechanism 23 to operate the recording head IJ
It becomes possible to engage H with the ink ejection surface. This allows
The blade 30 is projected into the movement path of the carriage 16 at an appropriate timing during the recording operation of the recording head IJH, or after the recovery processing using the head recovery device 26, and the recording head IJH moves as the carriage 16 moves. Wipe off condensation on the ejection surface, ink leakage or dust.

Further, the ink jet printer IJRA having the above-mentioned structure is provided with an automatic recording paper feeder (not shown).
Is provided, and the recording paper P is automatically fed.

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

FIG. 2 is a block diagram showing the configuration of the control circuit of the ink jet printer IJRA. In the figure showing the control circuit, 1700 is an interface for inputting a recording signal, 1701 is an MPU, 1702 is an MPU 170.
ROM for storing a control program executed by
Reference numeral 3 is a DRAM for storing various data (recording data, recording data supplied to the recording head IJH, etc.). Reference numeral 1704 is a gate array (GA) that controls the supply of print data to the print head IJH, and includes an interface 1700, an MPU 1701, and a RAM 1703.
It also controls data transfer between them. 1710 is a recording head IJ
A carrier motor for carrying H, 1709 is a carry motor for carrying the recording paper. Reference numeral 1705 denotes a head driver that drives the recording head IJH, and 1706 and 1707.
Are carrier motor 1709 and carrier motor 171 respectively.
It is a motor driver for driving 0.

The operation of the above control structure will be described. When a recording signal is input to the interface 1700, the gate array 17
The print signal is converted between the print signal 04 and the MPU 1701 to print data for printing. Then, the motor driver 17
06 and 1707 are driven, and the head driver 1
The print head IJH according to the print data sent to 705.
Is driven and recording is performed.

FIG. 3 is a sectional view schematically showing the structure of the substrate 301 of the recording head IJH. The substrate 301 is shown in FIG.
The internal equivalent circuit configuration is the same as the substrate of the conventional recording head shown in, and a heating element (electrothermal converter) that is an energy generating element that generates energy for ejecting ink, and a plurality of heating elements. A power transistor (driver) provided in a one-to-one relationship with the heating element for driving the heating element and a logic circuit such as a shift register or a latch circuit are formed on the same silicon substrate.

As shown in FIG. 3, the Si substrate 2 of P conductor is used.
Into 01, a dopant such as As is introduced by means of ion plantation and diffusion to form an N-type buried layer 202, and an N-type epitaxial layer 203 is formed thereabove. Further, impurities such as B are introduced into the N-type epitaxial layer 203 to form the P-type well region 204. After that, impurity introduction is repeated by a method such as photolithography, oxidation diffusion, and ion plantation, and N
A p-MOS 250 is formed in the type epitaxial region 203, and an n-MOS 251 is formed in the P-type well region. p-MO
The S250 and the n-MOS 251 are a gate wiring 215 made of polysilicon deposited by a CVD method through a gate insulating film 208 having a thickness of several hundreds, and a source region 205 and a drain region 20 into which an N-type or P-type impurity is introduced.
6 and so on.

The above-mentioned MOS transistors form the logic part of the latch circuit 103 and the shift register (S / R) 104.

Further, N serving as the driver 102 of the heating element
The PN-type power transistor 252 is formed by providing the collector region 211, the base region 212, the emitter region 213, etc. in the N-type epitaxial layer 203 by the steps such as impurity introduction and diffusion.

The elements are isolated from each other by an oxide film isolation region 253 formed by field oxidation. This field oxide film is used for the heating element 255.
In the lower part, it acts as the first heat storage layer 214.

After each element is formed, the interlayer insulating film 216 is formed.
Of PSG and BPSG are deposited by the CVD method, planarized by heat treatment, etc., and then the aluminum electrode 217 of the first layer is formed through the contact hole. In the heating element, the resistance layer 219 and another aluminum electrode 220 are formed so as to be laminated on each other in the same pattern. However, in the heating portion 255, the aluminum electrode 220 is cut out, and only the resistance layer 219 has a current. Is configured to communicate.
With this configuration, only the heat generating portion 255 generates heat. After that, S by plasma CVD method
An interlayer insulating film 218 such as iO is deposited, and a heater layer 219 and a second-layer aluminum electrode 218 are further provided through a through hole.
Is formed.

The protective film 221 is formed by plasma CVD.
An iN film is formed. The anti-cavitation film 222 is deposited on the uppermost layer by Ta or the like, and the pad portion 254 is opened and formed.

Although the power transistor is a bipolar transistor here, it may be a MOS transistor.

FIG. 4 is a diagram showing the structure of the substrate 301 of the recording head IJH.

First, the structure of the substrate will be described.

The substrate 301 has a generally rectangular shape,
64 heating elements 302 are arranged along the long side on one side.
Density of 360 pieces per 5.4 mm (ie 360 dp
In i), they are arranged at equal intervals. Along the other long side,
A plurality of input signal pads 310 used for connection with the recording device IJRA are arranged. In addition, a power transistor arrangement region 303 for arranging a power transistor for driving the heat generating element 302 is formed in a strip shape along the arrangement direction of the heat generating element 302 in a substantially central portion of the substrate 301. As described above, the power transistor and the heating element 30
Since there is a one-to-one correspondence with 2, the power transistor arrangement region 303 includes 64 power transistors, and these power transistors are arranged in one row in parallel with the arrangement direction of the heating elements 302. . The heating element 302 and the power transistor in the power transistor arrangement region 303 are electrically connected by the aluminum electrode 219 shown in FIG. The area where this wiring is provided is shown in FIG.
In the heater wiring portion 304.

Next, the structure around these heating elements 302 will be described with reference to FIG.

As described above, the Si substrate 201 having the first heat storage layer 214 and the interlayer insulating film 216 formed thereon are formed.
An interlayer insulating film 21 acting as a second heat storage layer
8, a resistance layer (heating element layer) 219, and an aluminum electrode (heater wiring layer) 220 are sequentially stacked. Aluminum electrode 220
Is partially removed in a groove shape by etching or the like in a portion to be the heat generating portion 255 of the heat generating element 302,
A part of the resistance layer 219 is exposed at the bottom of the groove. On the exposed resistance layer 219 and aluminum electrode 220,
A protective film 221 for protecting these layers from the influence of ink and a cavitation resistant film 222 formed as a Ta protective layer are sequentially laminated. These two protective layers also
The aluminum electrode 220 has a groove portion corresponding to the groove shape, and the ink can be film-boiling in this groove portion.

Further, other components on the substrate 301 will be described with reference to FIG.

A region between the power transistor wiring region 303 and the long side on the input signal pad 310 side is a logic circuit region 309. In the logic circuit area 309, a shift register, a latch circuit, and the like each formed of a CMOS logic circuit are formed. The input signal pad 310 is used to supply a signal to each circuit formed in the logic circuit area 309.

Further, relatively large pads 311 and 312 are provided at both ends of the long side of the substrate 301 on the side where the input signal pad 310 is provided. The pad 311 is a pad for commonly applying a predetermined heating element drive voltage (+ VH) to each heating element 302, and the pad 312 is a ground (GND) pad. At both ends of the power transistor arrangement region 303 in the longitudinal direction,
Each of them is provided with a heater 313 for adjusting temperature, and a sub-heater 314 is provided near one of the heaters 313.

Further, a diode 315 for a temperature sensor is provided at each end of the substrate 301 on the side of the heating element 302, and a through hole 317 is provided near this diode. In addition, the power transistor arrangement region 30
Through holes 316 are provided in the vicinity of the four corners of No. 3, respectively. These through holes 316 and 317 are provided to establish electrical connection with the two wiring layers arranged below. Further, marks 318 used for position detection at the time of manufacturing and assembling the recording head are formed at both ends of the power transistor wiring region 303 in the longitudinal direction.

FIG. 5 is an internal equivalent circuit diagram of a circuit mounted on the substrate of the printhead IJH.

In FIG. 5, the same elements as those of the recording head shown in FIG. 6 of the conventional example are designated by the same reference numerals,
The description here is omitted. In that figure, 124 is N
The MOS transistor 125 is a common terminal of the heat retaining heater 121 and the rank heater 123.

The characteristic point of the configuration shown in FIG.
(1) NM in the heat retention heater 121 that controls the temperature of the ink
The drain side of the OS transistor 124 is connected, and the gate side thereof is connected to the rank heater 123 and the common terminal 125. (2) One end of the heat retaining heater 121 is connected to the heating element driving power supply terminal 110. The source side of the NMOS transistor 124 and one connection end of the rank heater 123 are connected to the common terminal 111.

With such a configuration, when the resistance value of the heating element is monitored, it can be measured by applying a current to the common terminal 125, and when controlling the temperature of the ejected ink, the temperature is input from the common terminal 125. By changing and applying the voltage, the electric power supplied to the heat retention heater 121 is controlled and the temperature thereof is adjusted.

Such an instruction to supply a current to the common terminal 125 and its voltage control are performed by the M mounting the recording head IJH.
PU1701 executes, the actual current is head driver 1
It is input to the common terminal 124 of the recording head IJH via 705.

Therefore, according to the embodiment described above,
Since the signal input terminal to the heat retention heater and the input signal terminal to the rank heater can be made common, the number of terminals per substrate can be reduced. This gives, for example,
In a printhead or a full-line printhead configured by combining a plurality of such substrates, the number of terminals can be reduced by the number of combinations, which contributes to a reduction in the production cost of the printhead as a whole. It will be. Further, it contributes to making the cable connecting such a recording head with the recording apparatus thin or small.

In the above embodiment, particularly in the ink jet recording system, a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for ejecting ink is provided, and High density and high definition recording can be achieved by using a method of causing a change in ink state by energy.

With regard to its typical structure and principle, for example, US Pat. Nos. 4,723,129 and 4740 are applicable.
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 ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective 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 configuration in which a common slot is used as a discharge portion of the electrothermal converter, and Japanese Patent Laid-Open No. 59-63, which discloses a configuration 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, the length can be increased by combining a plurality of recording heads as disclosed in the above-mentioned specification. Either of the structure satisfying the requirement or the structure as one recording head integrally formed may be used.

In addition to the cartridge type recording head in which the ink tank is integrally provided in the recording head itself described in the above-described embodiment, the recording head is electrically attached to the apparatus main body by being attached to the apparatus main body. A replaceable chip-type recording head that enables various connections and supply of ink from the apparatus main body may be used.

Further, it is preferable to add a recovery means for the recording head, a preliminary means, etc. to the structure of the recording apparatus described above because the recording operation can be made more stable. Specific examples thereof include capping means for the recording head, cleaning means, pressurizing or sucking means, electrothermal converters or heating elements other than these, or preheating means by a combination thereof. Further, provision of a preliminary ejection mode for performing ejection different from recording is also effective for stable recording.

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 above-described embodiments, the explanation is made on the premise that the ink is a liquid, but even if the ink solidifies at room temperature or lower, one that softens or liquefies at room temperature is used. Or, in the inkjet method, it is general that the temperature of the ink itself is adjusted within a range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is in a stable ejection range.
It suffices that the ink is in a liquid state when the use recording signal is applied.

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 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.

Even when the present invention is applied to a system composed of a plurality of devices (for example, host computer, interface device, reader, printer, etc.), a device composed of one device (for example, a copying machine, a facsimile). Device).

[0070]

As described above, according to the present invention, since the terminals for inputting the signals to the monitor element and the preliminary heater are made common, the number of terminals which the recording head must have can be reduced. There is. In particular, for example,
In the case of a recording head or a full-line type recording head configured by combining a plurality of substrates as described in claim 4 so as to have many recording elements, the number of terminals can be reduced by the number of combinations. There is an advantage that such a recording head can be produced at low cost.

[0071]

[Brief description of drawings]

FIG. 1 is an external perspective view showing the outline of the configuration of an inkjet printer IJRA that is a typical embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a control circuit of the inkjet printer IJRA.

FIG. 3 is a cross-sectional view schematically showing a configuration of a substrate 301 of the recording head IJH.

FIG. 4 is a diagram showing a configuration of a substrate 301 of a recording head IJH.

FIG. 5 is an internal equivalent circuit diagram of a circuit mounted on the substrate of the printhead IJH.

FIG. 6 is a diagram showing an internal equivalent circuit of a logic circuit mounted on a recording head substrate having 64 heating elements (heating elements).

[Explanation of symbols]

101 heating element 102 power transistor 104 shift register 117 Latch circuit 118 3 → 8 decoder 119 AND circuit 120 rank heater terminal 121 Heat insulation heater 122 Heat insulation heater terminal 123 Rank heater 124 NMOS transistor 125 common terminals IJH recording head

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshiyuki Imanaka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (56) References JP-A-7-242004 (JP, A) JP-A-7 -76079 (JP, A) JP-A-6-155743 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B41J 2/05

Claims (6)

(57) [Claims] 1. A heating element, a drive circuit for driving the heating element, a shift register for inputting and temporarily storing image data, and a latch circuit for latching the image data stored in the shift register. A recording head mounted on one substrate, further comprising: a monitor element for monitoring the resistance of the heating element by causing a current to flow on the substrate; a preliminary heater used for head temperature adjustment; and the monitor element. And a common terminal for inputting a signal to the spare heater, the spare heater is connected to the drain side, and the common side is connected to the gate side.
The monitor element in which a monitor element and the common terminal are connected.
NMO for controlling child monitor and driving of the preliminary heater
An S-transistor, and a current is applied to the common terminal to provide the monitor element.
Is monitored and the voltage applied to the common terminal changes.
Change the heating temperature of the head by the preliminary heater
A recording head characterized by: 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 which ejects ink by utilizing thermal energy, and is provided with a thermal energy converter for generating thermal energy applied to the ink. The recording head according to item 1. 4. The recording head according to claim 1, wherein a plurality of the substrates are combined to include many recording elements. 5. A recording apparatus using the recording head according to claim 1, wherein monitor means for monitoring the resistance of the monitor element by applying a current to the common terminal, and inputting to the common terminal. A recording device, comprising: a voltage control unit that controls to change the voltage. 6. The recording apparatus according to claim 5 , wherein the voltage control unit adjusts the temperature of the recording head by changing the voltage.