JPH02179749A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To obtain images with favorable fixation and drying by such a switching as to lower a driving frequency for a recording head and a feeding velocity for a paper at the time of recording images on an OHP paper, as compared with those values at the time of normal recording. CONSTITUTION:A mode is selected by an OHP mode selecting key on a console. With a recording starting signal inputted, all of a feeding velocity for feeding a paper from a paper-supplying part 303 to registration rollers 415, 416, a feeding velocity for a belt in a belt-feeding part 304 and a discharging velocity for a paper at paper- discharging rollers 211, 212 are set in accordance with low-velocity mode feeding. Power supplies for a heating element A200, a heating element B201 and a fan 203 are switched ON, and auxiliary fixation is conducted. The degree of lowering in velocity for this mode varies depending on the materials of a coating agent on an OHP paper and of an ink, ejection quantity of the ink, and the like. Where ordinary papers and coated papers are fed at a velocity of 100m/sec and a driving frequency therefor is 1.6kHz, and when an appropriate feeding velocity for the OHP paper is 25mm/sec (i.e., 1/4 times 100mm/sec), a driving frequency therefor is 0.4kHz. Thereby, favorable fixation without overflow, bleeding or the like of the ink can be achieved in recording on the OHP paper.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an image recording device having functions such as a facsimile machine, a copying machine, and a printer, and a multifunctional device having such functions;
The present invention relates to an image recording device used as an output device for a workstation or the like.

[Conventional technology]

The non-equivalent recording method has recently attracted attention because the noise generated during recording is so small that it can be ignored. Among them, there is a possibility of high-speed recording,
Moreover, the inkjet recording method is an extremely powerful recording method that can perform recording on so-called plain paper without requiring any specific fixing process.

A recording head applied to an inkjet recording device generally includes a fine liquid ejection opening (orifice), a liquid path, an energy acting part provided in a part of this liquid path, and a droplet forming device that acts on the liquid in the acting part. It is equipped with an energy generation means for generating energy.

Energy generating means for generating such energy include recording methods using electromechanical transducers such as piezo elements, irradiating electromagnetic waves such as lasers, absorbing them into the liquid and generating heat, and the effect of the heat generated. A recording method using an energy generating means that ejects and flies droplets, or a recording method using an energy generating means that ejects a liquid by heating the liquid with an electrothermal converter such as a heating element having a heating resistor. There is. Among them, the recording l\\rad used in the inkjet recording method in which liquid is ejected using thermal energy, is a system in which liquid ejection ports (orifices) are arranged in high density to eject recording liquid droplets and form flying droplets. This makes it possible to record with high resolution. Among these, a recording head that uses an electrothermal converter as a thermal energy generating means is easy to make the overall size of the recording head compact, and is based on IC technology and microelectromechanical technology, which have recently made significant advances in technology and reliability in the semiconductor field. It is possible to fully utilize the advantages of processing technology, and it is easy to lengthen and planarize (two-dimensional), so it is easy to use multi-nozzles and high-density packaging, and it is also possible to mass produce high productivity ( It is also possible to provide an inkjet recording head and a device having the head, which is inexpensive to manufacture.

In this way, using an electrothermal converter as an energy generation means,
Generally, an ink sheet recording head manufactured through a semiconductor manufacturing process has a liquid path corresponding to each orifice, and thermal energy is applied to the liquid filling the liquid path for each liquid path to draw the liquid from the corresponding orifice. An electrothermal transducer is provided as a means for ejecting liquid to form flying droplets. Moreover, the structure is such that liquid is supplied to these liquid passages from a common liquid chamber communicating with each liquid passage.

FIG. 11 is a schematic configuration diagram of such an inkjet recording head, in which an electrothermal transducer 1103, an electrode 1104, and a liquid are formed on a substrate 1102 through semiconductor manufacturing process steps such as etching, vapor deposition, and sputtering. An inkjet recording head composed of a road wall 1105 and a top plate 1106 is shown.

A recording liquid 1112 is supplied from a liquid storage chamber (not shown) through a liquid supply pipe 1107 into a common liquid chamber 1108 of the recording head 1101. In the figure, 1109 is a liquid supply pipe connector. The liquid 1112 supplied into the common liquid chamber 1108 is supplied into the liquid path 1110 by a so-called capillary phenomenon, and is stably held by forming a meniscus at the discharge port surface (orifice surface) at the tip of the liquid path. By supplying electricity to the electrothermal converter 1103, the liquid on the surface of the electrothermal converter is rapidly heated, bubbles are generated in the liquid path, and the expansion and contraction of the bubbles causes the liquid to be discharged from the discharge port 1111. A droplet is formed. With the above-described configuration, a high-density ejection port arrangement such as an ejection port density of 16 nozzles/mm, 128 ejection ports or 256 ejection ports, or even a multi-nozzle inkjet in which ejection ports are arranged over the entire recording width can be achieved. A recording head can be formed.

FIG. 12 is a schematic perspective view showing a configuration example of an inkjet printing apparatus in which the above-described inkjet printing head is actually arranged in the printing apparatus.

In the same figure, a recording head 1101 similar to the recording head described above is driven by a motor 1216 to drive a rail 121.
It is constructed integrally with a carriage 1214 that reciprocates on 3a. Ink tank 1222Y.

The ink contained in 1222M, 1222C, 1222B is pumped by pumps 1223Y, 1223M, 1223c, 1
223B into the recording head 1101. The recording member (recording paper) is conveyed along the platen roller 1212 and temporarily stopped. Then, the recording head 1101 discharges ink while moving forward along the rails 1213a and 1213b to record an image. After recording an image for a predetermined paper width, the recording head 1101 moves again to the rail 1213a,
The recording paper moves backward along the line 1213b and returns to the home position, but during this time the recording paper is conveyed by a desired amount by the platen roller 1212 and stopped again. Then, image recording is performed by repeating such operations.

A recording method in which printing is performed while reciprocating the recording head on the stopped recording paper is hereinafter referred to as a serial scan method.

[Problem to be solved by the invention]

However, if the recording head is made multi-noise and elongated to the same width as the recording paper, the recording method will be completely different from the conventional serial scan method.

For this reason, various problems arise that are different from those of conventional serial scan type recording apparatuses.

One of them is that the multi-nozzle method can significantly increase the recording speed compared to the serial scan method. For this reason, when printing on paper with a slow ink absorption rate such as OHP (overhead projector) paper, ink fixation and drying problems may occur, and when overlapping ink for color printing, etc. Overflow, bleeding, etc. may become a problem.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an inkjet recording apparatus that can obtain good fixing without overflowing or bleeding of ink when recording on OHP paper.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention is designed to perform print recording by switching to reduce the driving frequency of the recording head and the conveyance speed of the paper, compared to normal image recording when recording an image on OHP paper. It is configured.

[Effect]

According to the present invention, with the above-described configuration, an image can be recorded on OHP paper that is well fixed and dried without ink bleeding or overflowing.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a schematic sectional view of an image recording apparatus for explaining one embodiment of the present invention. First, the outline of the image recording apparatus of this embodiment will be explained using FIG.

In the figure, 301 is a part of a scanner that reads a document and converts it into an electrical signal. A signal based on the converted signal is sent to the recording head unit 305 of the printer unit 302.
is given as a drive signal to Recording paper, which is one of the members to be recorded, stored in the paper feed section 303 is fed sheet by sheet toward the belt conveyance section 304 when necessary. When the recording paper passes through the belt conveyance section 304, an image is recorded by the recording head section 305, and then the recording paper is transferred to the fixing paper discharge section 307.
It is then sent out to the tray 420. Note that 306 is a recovery cap portion, which has a function to maintain the recording head portion 305 in a state where printing is possible at all times. Each of the above configurations will be explained in detail below.

First, the ink supply to the full-line elongated recording head used in this embodiment will be explained using FIG. 10. FIG. 10 is an explanatory diagram schematically showing the configuration of the elongated recording head and ink supply means, where 1601 is the recording head, 1652 is a common liquid chamber in the recording head 1601, and 1653 is a recording liquid ejection surface. 1654 is a discharge port for discharging liquid. However, the discharge port 1 of this embodiment
Numerals 653 are arranged in number in the recordable width of the target recording material, and selectively drive heating elements provided at unillustrated branch paths leading to the respective ejection ports 1653. It is possible to eject the recording liquid and perform recording without moving or scanning the head itself.

1655 is a recording liquid supply tank for supplying recording liquid to the recording head 1601; 1656 is a main tank for replenishing the supply tank 1655 with recording liquid;
55 to the recording head 16 through a supply pipe 1657.
When replenishing the recording liquid, the recording liquid can be refilled from the main tank 1656 to the supply tank 1655 by a recovery pump 1659 via a one-way replenishment rectifier valve 1658. Also, 16
60 is a one-way recovery rectifier valve used during a recovery operation to recover the ejection function of the recording head 1601;
1661 is a circulation pipe in which a recovery rectifier valve 1660 is interposed, and 1662 is the above-mentioned first supply pipe 16.
A solenoid valve 57 is installed, and 1663 is an air vent valve for the supply tank.

In the recording head 1601 and its recording supply system and recovery system configured in this way, when recording is performed, the solenoid valve 16
62 is kept in an open state, and recording liquid is supplied from the supply tank 1655 to the common liquid chamber 1652 by its own weight, and from the liquid chamber 1652 to the discharge port 165 via a liquid path (not shown).
I am guided by 3. In addition, during a recovery operation performed to remove air bubbles remaining in the common liquid chamber 1652 and the supply system and to cool the recording head 1601, the recovery pump 1659 is driven to supply the recording liquid to the common liquid chamber 16 through the circulation pipe 1661.
52 and from the common liquid chamber 1652 to the first supply pipe 16
57 allows the recording liquid to be returned to the supply tank 1655 for circulation. Furthermore, at the time of initial filling of the liquid path, etc., with the solenoid valve 1662 closed, the pump 1659 pumps the recording liquid through the circulation pipe 1661 to the common liquid chamber 1652, and as the bubbles are discharged, the recording liquid is discharged from the discharge port 1653. can be done.

Normally, such a recording head is left with ink remaining inside the ink ejection openings when not recording. A capping means having a cap that can be joined to the ejection port surface or the ejection port side of the print head is provided, and the cap and the print head are bonded during non-printing, so that the print head can be covered with a cap and the surroundings can be covered. evaporation of the ink liquid in the liquid path and by filling the air layer at the joint with ink vapor to bring the space formed by the cap and the recording head to the saturated vapor pressure of the ink. This prevents the accompanying increase in viscosity and drying of the ink in the liquid path. However, in low-humidity environments or when recording is stopped for a long period of time, the viscosity of the ink may increase even if the above-mentioned capping is performed to prevent the ink liquid from evaporating in the crossroads. During recording after the pause period, it may not be possible to prevent ink from being ejected from the ejection ports or from being ejected unstablely. In the present invention, the problem of whether or not ink is ejected for the first time after a pause is solved in the following way.
called "problem". To solve this problem, as described above, the recovery pump 1659 is driven to circulate and pressurize the ink, and an ink circulation and pressure means is also used to discharge the ink from all the ejection ports of the recording head. There is. Furthermore, if the above-mentioned non-ejection condition is slight, the entire energy generating means of the head is driven to perform an ink ejection operation similar to that used for recording on paper or the like. Since this is not ejection for recording an image, it is hereinafter referred to as "dry ejection" in the present invention.

As mentioned above, if the ink dries up due to being left in a non-recording state for a long time and its viscosity increases and it becomes stuck in the ejection port and/or the liquid path, pressurized circulation of the ink will cause the non-recording state to occur again. If the stuck state is slight in a relatively short period of time, the head is rotated to a state where printing can be performed by an idle ejection operation.

A recording member suitably used in this embodiment will be described.

In the inkjet recording method, small droplets of recording liquid called ink are ejected and recorded by adhering them to the surface of a recording paper such as paper. It is necessary that the image does not become blurry. In addition, the ink adhering to the recording member is quickly absorbed into the recording member, and there is no phenomenon of ink flowing out or seeping, especially when ink of different colors is repeatedly adhering to the same spot within a short period of time. It is preferable to have characteristics that can suppress the spread of printed dots to an extent that does not impair the clarity of the image quality. These characteristics may not be fully satisfied with copy paper called plain paper used in electrophotographic copying machines and other paper used as general recording paper. When printing with only one color or superimposing two colors on these papers, it is often possible to obtain a somewhat satisfactory image quality, but for example, when printing a full-color image by superimposing three or more colors of ink, When the amount of ink that adheres to the paper increases, it may not be possible to record a sufficiently satisfactory image quality.

In the inkjet recording apparatus of this embodiment, the paper that satisfies the above-mentioned characteristics is coated with a coating (for example, finely powdered silicic acid) on the base paper that can obtain the above-mentioned characteristics, as disclosed in Japanese Patent Application Laid-Open No. 148583/1983. It is preferable to use a recording member that has been subjected to. The ink is attached to the coating surface of the recording member. Therefore, in this embodiment, in order to record a higher quality image, coated paper is used when recording an image using ink of three or more colors, and coated paper is used when recording an image using ink of one or two colors. I try to select and use non-coated paper (paper that is not coated as described above). However, it is perfectly acceptable to record images using coated paper using one or two color inks.

In the scanner part 301, 401 is a document, and 402 is a document scanning unit that scans the document. The document scanning unit 402 includes a rod eye lens 403, a life-size color separation line sensor (color image sensor) 404, and an exposure means 405. At least when the document scanning unit 402 moves and scans in the direction of arrow A to read the image of the document 401 on the document table, the exposure lamp in the exposure means 405 in the document scanning unit 402 is turned on.
Reflected light from a document 401 is guided by a rod array lens 403 to a 1-magnification color separation line sensor (hereinafter referred to as a reading sensor) 40 which is a color information reading sensor.
4, reads the color image information of the document for each color, and converts it into electrical digital signals. This digital signal is sent to the printer section 302.

Based on these signals, drive signals are supplied to the recording heads for each color, and liquid is ejected.

FIGS. 2(a) and 2(b) are schematic cross-sectional views of a part of the printer in the image recording apparatus according to the present invention. The state of the recording head during the recovery operation will be explained using FIG. 2(a). I.C., L.M.

IY and IBk are inkjet recording heads to which cyan, magenta, yellow, and black inks are supplied, respectively. Each head is fixed to the head block 6 with high precision, and the parallelism of each head, the distance between the heads, etc. are guaranteed within a desired precision. Head IC and LM of each of these colors.

Near the ejection ports of IY and IBk, there are ink absorbers, 3C, for absorbing ink corresponding to the ejection ports of each head.
, 3M, 3Y, and 3Bk are installed.

The ink absorbers 3C, 3M, 3Y, and 3Bk are supported by an absorber guide 7 so as to be movable toward and away from the ejection surfaces of the recording heads IC, LM, IY, and IBk. Figure 2 (a
), the ink absorbers 3C and 3Y are attached to the recording head I.
c and IY are shown separated from the ejection surface. Further, the ink absorbers 3M and 3Bk are connected to the recording head LM.
It is shown in contact with the discharge surface of IBk and IBk.

An ink partition plate 8 is provided between the ink absorbers. Further, an ink seal 4 is provided between each partition plate 8 and the head block 6 to seal ink between each color. Further, an ink squeezing member 5 is provided near each ink absorber, and the ink absorbers 3C, 3M, and 3Y are controlled by a lever (not shown).

It is now possible to squeeze out the ink absorbed by 38k and let it fall. FIG. 2(a) shows a state in which the ink absorber 3Y of the yellow head IY is squeezed.

A head block 6 to which recording heads Ic, IM, IY, and IBk are fixed is removably inserted into a block stay 9 via a rail 15. Further, this block stay 9 is rotatable around the rotation center N, together with the head block 7 and each color head. The recovery system container 2 can be moved from the recovery operation state in FIG. 2(a) to the retreat position shown by the two-dot chain line by a moving mechanism (not shown). Further, an ink discharger 13 is provided at the bottom of the recovery system container 2, and the recording head IC, IM, IY
, IBk, and the ink absorbers 3C, 3M, 3Y
, 3Bk and collected is guided to a discharge ink tank (not shown) via a discharge ink hose (not shown).

FIG. 2(b) is a schematic cross-sectional view of essential parts showing the state of the recording head during image recording. After the recovery system container 2 moves to the retracted position from the state shown in FIG. 2(a) (after moving to the area indicated by the two-dot chain line in FIG. 2(a)), the recording head moves as shown in FIG.
As shown in b), it has been rotated to the horizontal position. In this state, ink is ejected based on the image recording signal of each head, and an image is formed on the recording paper that is conveyed at a desired distance from the ejection surface P of the recording head.

Next, the recovery operation by the recovery system will be explained in more detail.

For convenience, the recovery operation is divided into three parts: (1) capping, (2) preliminary (empty) ejection, and (2) ink discharge, and these operations will be explained in order.

First, the capping operation will be explained.

FIG. 3 is a schematic diagram showing the capping state of the recording head. In this figure, recording heads IC, IM, and IY are arranged side by side in a head block 6.

IBk is a recovery/cap part 30 as a discharge recovery means.
6. The recovery system container 2 includes an ink seal 4, a partition plate 8, and ink absorbers 3C and 3M.

3Y and 38k are disposed, and the ink absorber usually has a certain gap from the head ejection surface. As a result, the vicinity of the ejection ports of the recording heads lc, IM, IY, and IBk are covered by the ink seal 4, the partition plate 8, and the ink absorbers 3C, 3.
Surrounded by M, 3Y, and 38k, it is possible to maintain an appropriate moist state and prevent the head ejection port from drying out. As described above, capping prevents ink from being ejected when the recording head is at rest, during standby, etc., and also protects the ejection ports and prevents dust and the like from adhering to or entering the vicinity of the ejection ports.

Next, (1) preliminary (empty) ejection operation will be explained. The diagram is a schematic diagram showing a dry ejection operation. Similar to the capping operation described above, the print head Ic, 3C, 3M, 3Y, 3Bk, which is held with a certain gap from the print head ejection surface in the capped state,
An arbitrary number of ink ejection pulses are applied to the ejection energy generating means of all the IM, IY, and IBk heads. In this way, it is possible to prevent ejection failure due to ink sticking to all ejection ports, and prevent ejection failure and image disturbance due to ink with a changed viscosity. Normally, the idle ejection operation is set to be performed when copying is turned on.

Next, (1) ink ejection operation will be explained. Figure 5 (
1) to (4) are the recovery/cap section 3 when performing ink pressurized circulation operation in the ink supply system as ink discharge operation.
FIG. 2 is a schematic diagram showing the operation in 06. The operations in the recovery/cap section 306 include (1) normal capping, (2) pressurized ink circulation, (3) absorbent squeezing/wiping, (
4) There are cycles (1) to (4) of absorber contact.

(1) to (4) in FIG. 11 correspond to these.

First, (L) capping refers to the above-mentioned (2) capping, and is a normal standby state or hibernation state. In this state, when the pressurized ink circulation mode is selected, for example, by a command from the user or the host computer, the state shown in FIG. 11(2) is reached. That is, each of the ink absorbers 3C, 3M, 3Y, and 3Bk, which were held with a certain gap, is moved to the recording head IC.

It contacts each of IM, IY, and IBk. In this state, the corresponding ink absorbers and head ejection surfaces are joined together. In this state, each recording head 3C, 3M, 3
Ink supply pumps (not shown) are driven in Y and 3Bk to forcibly increase the ink supply pressure. As a result, the ink circulates through the ink supply system through the inside of the head, and internal air bubbles are removed, and the pressurized ink is also discharged from the ejection ports. As a result, dust and the like adhering to the ejection surface are also removed together with the discharged ink, and the vicinity of the ejection port is cleaned. As described above, the ink discharged from the head discharge ports is absorbed by the ink absorber 3 (3C,
3M, 3Y, 3Blc) without leaking to other parts, and the ink that exceeds the maximum saturation amount in the absorber falls into the recovery container 2 through the absorber due to the ink's own weight. , discharge ink 1
3 and is guided into a drain ink tank (not shown) by a drain ink hose 121. The pressurized circulation time at this time, that is, the pressurization time of the supply pump, is preferably about 0.5 seconds to several seconds in view of the efficiency of removing fixed ink and bubbles.

Next, (3) absorbent squeezing and wiping will be explained.

(2) When the pressurized circulation is completed, the ink absorber 3 that was in contact with the head ejection surface is separated from the ejection surface again. In this state, the ink that is almost saturated in the ink absorber 3 is squeezed out by the squeezing member 5. The squeezed ink travels through the absorber guide 7 and the partition plate 8 due to its own weight, falls into the recovery container 2, and is discharged into the ink drain tank 13.
The ink is guided through the ink drain hose 12 into the drain ink tank.

At the same time, the ink absorber 3 is removed from the head ejection surface, and at the same time as the absorber is squeezed, the ejection surface wiping blade 88 is driven to remove the ejected ink, dirt, and deposits remaining on the head ejection surface. etc. can be wiped out. The wiped ink and the like fall onto the ink absorber 3, but since the above-mentioned squeezing operation is being performed at the same time, these fallen objects also fall into the recovery container 2 along with the squeezed out ink. It is further guided to the waste ink tank. That is, at the same time as the ink absorber 3 is removed from the ejection surface, the blade 88 removes the adhering residue on the ink ejecting surface and squeezes out the adhering material together with the excess ink in the ink absorber. .

This is the above-mentioned (3) absorber squeezing and wiping operation. When the ink absorber 3 is squeezed by the throttle member 5, its absorption capacity is restored and it is ready for the next ink absorption. The ink absorber 3 is preferably made of, for example, PVF resin, which is a highly absorbent sponge, and is preferably one that can withstand repeated use. In this example, Bell Eater (trade name) manufactured by Kanebo Co., Ltd., for example, was used. The absorber, which has squeezed out the absorbed ink, then comes into contact with the ejection surface of the head again. This is (4) absorber contact. In the step (2), the absorber was almost saturated, so the ink that could not be completely absorbed from the ejection surface of the head was squeezed, and the absorption capacity was restored.
It is completely cleaned by contacting the clean absorber.

After performing the series of operations (1) to (4), the capping (1), that is, the standby state is performed again, and the cleaned head is maintained in good condition. Normally, these pressurized circulation operations are performed when the power of the main body is turned on or after a long standby period.

As described above, by performing the recovery operations of ■cap, ■dry discharge, and ■ink pressurization circulation, ink discharge, that is, disturbances in recorded images due to discharge failure during image formation can be prevented (
recovery).

Next, the printing operation will be explained. Figure 6(a)-(
f) is a state diagram when printing operation starts from the standby state of the recovery system described above. First, regarding (a) cap, it is the above-mentioned (2) cap state, which is a normal standby state or a hibernation state. By selecting the print mode (copy ON) in this state, the above-described idle ejection operation is first performed. Next, see Figure 6 (
b) The state shown in "head up" is reached, that is, the state in which the recording head section 305 is retracted upward. In this state, the recovery system container 2 as the recovery/cap part 306
moves toward the upper right in the figure. This state is (C) unit open, and after this state, (d) head down is performed. As a result, as shown in FIG. 6(d), the head is placed in a printable state (position),
Further, the recovery system container 2 is placed in the retreat position. In this state,
Recording paper is passed from the right direction in the figure, keeping a constant gap from the head ejection surface, while the heads IC, LM, IY,
An image signal is input to lBk, ink is ejected,
ij! Printing is done on paper.

After the print on the recording paper is completed, that is, the head has finished discharging the ink, the head-up operation is performed again as shown in FIG. 6(e), and then the head is recovered as shown in FIG. 6(r). The system container 2 is moved to the head side position and is again shown in FIG. 6 (
The printer enters the state a), that is, the cap state, and enters the standby state in preparation for the next printing. A normal copy operation is performed through the series of operations (a) to (f) above. In addition, the above-mentioned (1) ink circulation can be performed by performing the Ca') cap operation in this operation, that is, at a predetermined timing during standby operation, for example, when the power is turned on or every fixed period of time. It is possible to prevent a decrease in image quality and obtain a good image.

Figure 7 shows the registration rollers (belt conveyance section) of the recording member (recording paper) conveyance means (Fig.
6), the recording paper reaches the conveyor belt 101 along guide plates 417 and 418. The conveyor belt lot has an insulating layer (preferably with a volume resistance of 1012 Ω・cm or more) on the side where the recording paper is placed, and a conductive layer (volume resistance 10” Ω・cm or more) on the opposite side.
It is desirable to set it to Cm or less. ) has a two-layer structure. This conveyor belt 101 is wound around a driving roller 102, a driven roller 103, and tension rollers 104 and 105, and is attached with a tension of, for example, 2 to 5 kg. The conveyor belt 101 is moved in the direction of arrow AA in the figure by a motor (not shown) that is connected to a drive roller 102 and applies a driving force to the drive roller 102 .

The recording paper is placed on the conveyor belt 101 immediately in front of the conductive roller 107. At this time, the surface of the conveyor belt 101 is given a potential of several hundred to several thousand volts by the charger 106. When the recording paper placed on the conveyor belt 101 reaches the grounded conductive roller 107, the recording paper and the conveyor belt lO
Since the recording paper is maintained in close contact with the conveyor belt 101 by electrostatic attraction, the recording paper moves together with the conveyor belt 101 in close contact with the conveyor belt 101.

In this state, the recording paper reaches the recording area facing the recording head section 305. The recording head unit 305 includes a head block 6, recording heads Ic, IM, IY, and IBk, and a platen 115 is provided on the side facing the recording heads IC, IM, IY, and IBk via a conveyor belt lot. ing. Further, a pin 116 is provided on the platen 115, and a spring 117 and a guide pin 118 cause the platen 11 to
5 is pressed and supported on the recording head section 305 side. In the recording area, recording heads Ic, LM, IY, IBk
and the recording surface of the recording paper to the desired setting value.
In order to obtain high-quality image recording, it is desirable to maintain an accuracy of about 0 μm. For this purpose, the platen 115 is arranged so that the platen 115 has a surface in contact with the conveyor belt 101 so that the conveyor belt 101 substantially forms a flat surface in the recording area.
The flatness of No. 15 is kept within several tens of μm.

Further, the recording heads IC, IM, IY, and IBk are positioned and fixed to the head block 6 so that the flatness of the plane formed by the ejection port surfaces of all the heads is within about several tens of μm. Further, a pin 116 for positioning is attached to the platen 115. In this state, the platen 115 is guided by the guide pin 118, and the spring 1
If the repulsive force of pin 117 pushes it up in the direction of head block 6, the top of pin 116 and head block 6 will come into contact.
A gap l is formed for the recording paper to pass through. When the recording paper is conveyed in this configuration, the recording paper is in close contact with the conveyor belt (101) due to electrostatic adsorption force, so the distance between the recording surface of the recording paper and the ejection port surface of each recording head in the recording area is Accuracy is kept within the desired range for the setpoint.

When the recording paper passes through this recording area, the recording head Ic,
Images are recorded in sequence according to recording information using LM, IY, and IBk. At this time, if the speed fluctuation of the conveyor belt 101 is large, the recording position by each head will be shifted, resulting in color misregistration and color unevenness in the color image. In order to prevent this, the thickness accuracy of the conveyor belt 101, the drive roller 10
The outer diameter deflection of No. 2, the rotation accuracy of the drive motor, etc. are kept within desired ranges, and the speed fluctuation of the conveyor belt 101 is configured to be sufficiently small to cause no substantial problem.

The recording paper recorded in the recording area reaches the drive roller 102 while remaining in close contact with the conveyor belt 101, where it is separated from the conveyor belt 101 by the curvature of the conveyor belt formed by the drive roller 102 and is sent to the fixing section.

After that, the surface of the conveyor belt lO1 is covered with an ink absorber 119.
It is cleaned by a cleaner 120 equipped with.

The ink absorber 119 is formed of a continuous porous member such as polyvinyl formal resin, and the absorbed ink flows out from the opening 120 and is collected.

In this embodiment, an example is shown in which the conveyor belt 101 has a two-layer structure having an insulating layer and a conductive layer. Alternatively, it may have a multilayer structure including an insulating layer and a conductive layer.

The configuration of the fixing section will be explained in detail below.

In the inkjet recording method, ink is attached to a recording member, and the ink permeates into the recording member and becomes fixed. Alternatively, the ink is fixed on the recording member through an evaporation process of the ink solvent.

However, the time from when this ink adheres until it is fixed, that is, the fixing speed, not only depends on the composition and physical properties of the recording member, but also varies greatly depending on the external atmosphere. The settling speed cannot be made shorter than a certain time due to physical properties.

In many conventional serial scan recording apparatuses, fixing performance can be addressed with a somewhat simple configuration due to the recording speed. However, in recent years, as high-speed recording and color recording have been performed using line printers and the like, there have been cases where the ink is not sufficiently fixed on the recording member and is transported and discharged outside the apparatus.

Therefore, a fixing means is required to shorten the fixing speed and improve efficiency, and the configuration thereof is shown in FIG.

In the figure, a heating element 200 connects a surface of a recording member 210 to which no ink is attached (non-recording surface) to another heating element 2.
01 heats each surface of the recording member 210 to which ink is attached (recording surface). This heating element may be a halogen lamp, a sheathed heater, a thermistor, etc., but in this configuration, the heating element 200 uses several thermistors with a temperature control function, and is made of aluminum or the like with excellent heat transfer properties. The recorded member 2
10 non-recording surfaces were contact heated. On the other hand, the heating element 20
1 uses a halogen heater, and a fan 203 provided above a heating element 201 sends warm air onto the recording member 210 to heat the recording surface of the recording member 210 in a non-contact manner.

Even if the recording member 210 rises from the conveyor table 202 due to ink adhesion and curls peculiar to inkjet, the recording member 210 is reliably sent along the hot conveyor table 202 because the fan 203 sends warm air downward. . Therefore, since both sides of the recording member 210 are sufficiently dried, ink penetration is promoted, and the fixing speed is significantly reduced due to the synergistic effect.

The fixing temperature is set by a thermistor and a thermostat 204 that controls the temperature of the heater, and can be appropriately controlled according to the paper quality of the recording material. In addition, in order to prevent the fixing heat from affecting the ink in the head and supply system, a partition plate 205 with a heat insulating material such as glass fiber bonded to the surface is installed, and the heater holder 206 is made of heat resistant material such as polyphenylene oxide (PPO). Uses superior resin to prevent excessive transfer of fixing heat. Furthermore, an exhaust fan 207 is provided to exhaust excess fixing heat to the outside of the machine.

In addition, a heater cover 208 such as a wire mesh is installed in consideration of safety in the event of a jam of the recording member.

With the above configuration, the recording member 210 can be fixed by direct heating on the non-recording surface and heating with hot air on the recording surface, thereby preventing the recording from occurring in the inkjet recording method, especially in color inkjet recording in which ink droplets are overlaid, for example. It is possible to prevent deterioration in fixing performance due to curling of the member.

Next, the sequence of image recording after power-on of the present apparatus will be explained using the diagrams of FIGS. 1 to 2 and 3 to 9, and the flowcharts of FIGS. 13 to 21. 14 to 21 show subroutines of the flowchart of FIG. 14'.

First, when the power of the image recording device is turned on, the state diagram shown in Fig. 5 shows (1) capping, (2) pressurized ink circulation, (3) absorber squeezing, and (4) absorber contact. A series of operations (subroutine in Figure 14: ink pressurization circulation operation)
After that, the state returns to (1) capping state. Due to this series of operations (Step 1 in Figure 3), the device is stopped for a long time before the power is turned on, and the ink thickens (dries).
It is possible to prevent ink from not ejecting due to sticking or bubbles (increased viscosity due to evaporation of the solvent). The series of operations that follow the above (1) capping, (2) ink pressurization circulation, (3) absorber squeezing, (4) absorber contact, and (1) capping are hereinafter referred to as ink pressurization circulation operation. The ink pressurization circulation operation is not executed only immediately after power is turned on. For example, if the ink is not used for a long period of time after being turned on, or if it is used in a high temperature environment where ink is likely to thicken, etc.
Considering that problems such as sticking and bubble formation may occur if left unused, the ink is pressurized and circulated every fixed period of time (within an allowable period in which the above problems do not occur, hereinafter referred to as cycle time) using a timer or the like. The problem is solved by making the user perform an action. Furthermore, a humidity sensor (not shown) is provided near the recording head unit 305, and its signals are used to control changes in how many hours the ink pressurization circulation operation is performed and for how many seconds the ink pressurization time is performed. It is carried out. That is, when used in a low humidity condition, the cycle time is shortened or the ink pressurization time is lengthened. It has also been confirmed that changing both at the same time is even more effective.

Here, unless a recording start signal is input, the capping state shown in FIG. 3 is maintained. When the recording start signal is input, as explained in FIG. 4, a blank discharge operation is performed in which a fixed number of discharge pulses are given to all nozzles of all recording heads to cause them to discharge ink, thereby preventing non-discharge immediately before recording. conduct. This is shown in step 2 in FIG. The number of pulses for this idle ejection is also controlled by the signal from the humidity sensor, similar to the above-described ink pressurization circulation operation. That is, when the humidity is low, the number of idle ejection pulses is increased. The difference in effectiveness in preventing ejection failure between the ink pressurization circulation operation and the idle ejection operation is larger in the former, and therefore even the idle ejection operation cannot prevent ejection failure due to ink thickening, sticking, etc. This is a determining factor in the cycle time for the pressurized ink circulation operation.Therefore, when not in use, the capping means shuts off the ejection surface of the recording head from the outside air and prevents the ink from drying and sticking to some extent. , is configured such that all the nozzles of the head become ready for ejection only by a dry ejection operation.This dry ejection operation is performed as shown in FIG. 16 ( As shown in a) to (d), after the head moves upward and retreats, a unit open operation is performed in which the head retreats to the upper right direction of the recovery container 2. This operation is shown in FIG. 16 as a subroutine: unit oven operation.Continued. Then, the head unit 305 swings around the rotation center N so that the head ejection surface is vertically downward, that is, facing the surface of the transport head lot (head down operation is performed. This is shown in step 3 in FIG. 13). ).The head part 305 comes into contact with an abutment surface (not shown) provided on the head block 6 and a pin 116 provided on the platen 115, and is pushed down slightly against the spring 117 pushing up the platen 115. The stop position is detected by a print position detection sensor and the print position is stopped.Furthermore, a worm gear (not shown) is used as part of the transmission system for the drive source for swinging the head section 305. Due to the characteristics of the advancing angle, the hend portion 305 can be maintained in a stopped state without being pushed up by the reaction force of the spring 117.The head is now ready for printing.Next, a paper feeding operation is performed. As shown in the subroutine flowchart in FIG. 23, a recording member (paper) stored in a cassette 411 is fed by a pickup roller 412, passes through conveyance rollers 413, 414 and a guide section 419, and then stops at a register roller pair 415, 4
It is fed into the nip section of No. 16.

Here, after the leading edge of the paper comes into contact with the nip portion of the pair of register rollers 415 and 416, the paper is further fed out by the conveyance rollers 413 and 414 for a certain amount of time, and a loop is formed in the guide portion 419 in the paper by that amount. be done. This operation is a means of register alignment normally performed by electrophotographic copying machines, etc., and the loop force is used to align the leading edge of the sheet and correct paper skew.

Next, the register roller pair 415, 416 starts rotating and is sent onto the conveyor belt 101 via the guides 417, 418. Based on the signal to start the rotation of the register roller pair 415, 416, a signal to start scanning the document is generated. A print start signal is issued for each head IC, IM, IY, and IBk. The recording paper fed onto the conveyor belt 101 is brought into close contact with the surface of the conveyor belt 101 sequentially from its tip by electrostatic adsorption force, and the recording heads IC, IM, IY, LBk
When passing directly under the recording paper, printing is performed with the above-described means maintaining an appropriate gap between the head ejection surface and the recording paper surface. This situation is shown as a subroutine flowchart in FIG. After that, the paper is conveyed to the fixing/discharge unit 307, but when the paper is passed from the conveyor belt 101 to the guide 213, the diameter of the drive roller 102 is set relatively small, and the stiffness of the paper is This is done by means of so-called curvature separation, which causes natural separation. Here, the diameter of the drive roller 102 is determined by the distance traveled by the surface of the belt 101 that is frictionally driven by one rotation of the drive roller 102 between the first head, IC, and the fourth head, IB.
It is set to be equal to the distance between the respective ejection ports of k. This is done in consideration of the fact that if there is an eccentric component in the diameter of the drive roller 102, it will occur as a registration shift on the image.

Ideally, the surface of the belt lO1 would be driven by one rotation of the drive roller by the distance between the ejection ports of adjacent heads, but in consideration of mechanical strength, the surface of the drive roller 10
There is a limit to the minimum value of the diameter of 2, and when this is taken into account, it is relatively large.

This requires three times the distance between the four heads, resulting in an increase in the size of the device. Therefore, the head distance is the farthest, and the first one is the one that includes many other causes of registration misalignment.
The interval between the th head and the 4th head is considered. However, it may be between the first head and the third head (of course, it may also be between adjacent heads,
It is not limited to the above. However, some consideration must be given to the diameter of the drive roller and the distance between the heads as described above.

Next, there is a fixing process for the paper sent to the fixing/discharging unit 307, and there are three modes in this regard. This will be explained using the subroutine flowchart in FIG. As mentioned above (when using coated paper as recording paper, there is no need for fixing, but when using non-coated paper called plain paper in so-called electrophotographic copying machines etc., a fixing means is required. The first mode is the plain paper mode, and when printing is performed on plain paper, the heating element A200 and the heating element B201 are simultaneously powered on by the recording start signal.The fan 203 is powered on at the same time. A timer means receives the rotation start signal of the register rollers 415 and 416 at the timing when the paper is transferred from the conveyor belt 101 to the guide 213.

This is because it takes about 1 to 2 seconds for the halogen heater of the heating element B201 to rise to the set temperature, and if the fan 203 is rotated and air is applied to the halogen heater from the time it starts up, this rise time will be extended, and the paper will move to the fixing section. 30
This is because the temperature does not reach the set temperature when the toner is conveyed to No. 7, and the fixing effect is degraded. Next, when using the coated paper in the second mode in FIG. 19 as recording paper, a mode key for selecting coated paper is provided on the operation section (not shown).
After selecting this key, image recording is performed in response to a recording start signal, but at this time, power is not turned on for both the heating element A 200 and the heating element B 201. As described above, in coated paper, the ink is quickly absorbed into the paper, so that the above-mentioned fixing assisting means is not necessary. However, in consideration of the unlikely event of an operational error, the first mode, plain paper mode, is the priority mode, and the second mode, coated paper mode, is not selected by the operator as described above. The fixing auxiliary means is activated. Therefore, even if an image compatible with coated paper is mistakenly printed on plain paper, the problem of ink being offset to the discharge roller 211 (described later) and disturbing other recording papers can be prevented.

Furthermore, this device has a third mode shown in Fig. 20, which is an overhead projector film (OH
P) Paper (film) mode.

The OHP paper used in this device has a coating that has the same characteristics as coated paper, but despite this, if you print repeatedly on the same spot in a short period of time, the ink may run out or bleed. . Furthermore, it takes a long time for the ink to be completely absorbed into the coating layer, and if something comes into contact with the image surface within a short time after printing, problems such as image disturbance and offset may occur. To prevent this problem, the next time the images are superimposed is lengthened to allow time for the ink to be absorbed. Furthermore, to prevent offset etc., the time from printing to contacting the image surface is lengthened. Alternatively, it is conceivable to intervene with a fixing means during that time. In this device, all conveyance speeds related to paper feeding, such as paper feed speed, heald conveyance speed, and ejection speed, are reduced to a speed that solves the above problem while maintaining the ratios adopted in the first and second modes. (Low speed mode) At the same time, of course, the drive frequency of the head is also changed so that an appropriate image can be printed. In other words,
The operation unit (not shown) is provided with an OHP mode selection key, and when this mode is selected and a recording start signal is input, the registration roller 415 is moved from the paper feed unit 303.
, 416, the belt conveyance speed of the belt conveyance unit 304, and the discharge speed of the paper discharge rollers 211 and 212 are all set to the low speed mode conveyance, and the heating element A20
0, heating element B201. The fan 203 is also powered on at the same timing as in the first mode to assist in fixing.

Also, as mentioned above, the first. Since the conveyance speed and ejection speed of the belt are also lower than in the second mode, the effect of fixing is further increased.

The degree of speed reduction in this third mode cannot be determined in part because it varies depending on the coating agent and ink material on the OHP paper, the amount of ink ejected, etc. However, for example, if the plain paper or coated paper is transported at a transport speed of lOOm m/sec and its driving frequency is 1.6KHz, the appropriate transport speed for OHP paper is 1/4 of that, 25mm/sec.
sec, an appropriate image can be obtained by setting the driving frequency to 0.4 KHz.

Here, as mentioned above, O
In contrast to HP paper, plain paper and coated paper are hereinafter generally referred to as general paper.

The above-mentioned plain paper, coated paper, and OHP paper also end up at the paper ejection roller 211. The sheets are transported, kicked out, and stacked on the tray 420 by the paper transport section 212, but the transport speeds of the respective paper transport sections described above are different, and the reasons and details thereof will be described below.

In the configuration of this apparatus, the process speed determined by the recording speed of the apparatus is achieved by the conveyance speed of the conveyor belt lot. That is, the conveyance speed of the conveyor belt 101 is set to be the same as the process speed. Therefore, if printing from the head is done at a correspondingly accurate speed, if the conveyance speed of the conveyor belt 101 is slower than the set speed, the image will shrink in the conveyance direction compared to the normal one, and conversely, if it is faster, it will expand and print. It will be formed.

On the other hand, the conveyance speed of the register rollers 415 and 416 is set to be slightly faster than the conveyance speed of the conveyance bell h101. This is to prevent the conveyance force of the register rollers 415 and 416 from affecting the conveyance force of the belt 101. For example, if the conveyance speed of the register rollers 415 and 416 is set to be slower than the speed of the bell l-101, the paper is conveyed by the register rollers 415 and 416 and the receiver is passed to the belt 101, and the electrostatic charge is applied to the surface of the belt. However, at the position where the first head starts printing, only a portion of the paper from the leading edge is still attracted, and at this time, the conveying force of the register roller 415.4L6 is equal to or less than that of the belt lO1. Register roller 415 overcomes the conveying force
, 416, the belt l
As the conveyance of O1 progresses, the number of sheets being attracted increases, and an abnormal image is formed until the conveyance force overcomes the conveyance force of the rollers 415 and 416. For this reason, this device uses 4 pairs of rollers.
The conveying speed of 15° 416 is set higher than the conveying speed of the belt 101, and distortion of the paper caused by the speed difference is eliminated by forming a loop between the guides 417 and 418. Therefore, in this configuration, the roller pairs 415, 4
The conveying force of the belt 101 does not affect the conveying force of the belt 101. However, if the speed difference is set to a large value, the loop becomes thick and the suction operation becomes unstable due to flapping, etc. Therefore, the speed difference should be zero or very small to the extent that the speed difference does not reverse, and experimentally the ratio is 0 to 1. It has been found that a value of about 1.5% is good.Next, we will discuss the conveyance speed of the paper discharge section.In a normal configuration, the conveyance speed of the belt should be adjusted as in the relationship between the registration roller pair and the conveyance belt described above. Belt 101 and paper ejection roller 211゜2 so as not to affect the
However, in this apparatus, a fixing means such as a heating element A200 is installed on the downstream side of the belt conveyance device 304, which also serves as a guide, and the sheet is moved along the surface of the conveyance table 202. Since the sheet is heated from the back side, if a loop is formed here, the sheet will not be able to follow the surface of the conveyor table 202, and the fixing effect will be significantly reduced. Therefore, in the configuration of this apparatus, the conveyance speed of the paper ejection rollers 211 and 212 is set to be faster than the conveyance speed of the belt 101, so that the paper does not form a loop. Further, at this time, the conveyance table 20 of the heating element A200 is placed at a position slightly higher than the plane obtained by connecting the suction surface of the belt 101 and the nip position of the paper ejection rollers 211 and 212.
2 paper transport surfaces are set, and when the leading edge of the paper is sandwiched between paper ejection rollers 211 and 212, the paper is further transported along the surface of the transport table 202. Here, the paper ejection rollers 211, 212 are adjusted so that the conveying force of the paper ejection rollers 211, 212 does not become larger than the suction force of the belt 101 against the paper.
The conveying force of 2 has been optimized. The surface of the paper ejection roller 211 that comes into contact with the image surface of the paper is flocked with nylon fibers to reduce the frictional force, taking into consideration measures to prevent offset during fixing. ) etc., thereby achieving a conveying force lower than that of the belt 101.

The above-mentioned transport speed configuration allows smooth recording without disturbing the image during printing.

Now, to explain in detail the conveying performance of the belt conveying section 304, as mentioned above, fluctuations in the conveying speed of this conveying section 304 not only affect the expansion and contraction of the image, but also minute fluctuations in speed can affect color images, etc. When an image is formed by overlapping inks, it causes image defects such as misregistration and color unevenness. Therefore, the drive source of the drive roller 102 and the drive roller 10
The conveyance movement of the belt 101 (transport wow-flare) must be carried out with sufficient accuracy, giving due consideration to the outer diameter accuracy of the belt 101 and the thickness accuracy of the belt 101. In addition to these factors, consideration must also be given to factors that cause disturbance to the conveying section 304 and worsen wow and flutter. When it is handed over to me, as mentioned above,
The conveyance speed of the register roller pair 415, 416 is the same as that of the belt 1.
Since the conveyance speed is faster than that of 01, the belt lot has a structure in which it is pushed by the paper, and this external force worsens the wow and flutter of the belt 101. If printing was in progress on the previous sheet of paper at this point, the image would suffer from color unevenness, misregistration, etc., as described above.

To prevent this problem, when continuously recording images in this device, the paper is passed onto the bell l-101 at a timing when the trailing edge of the previous paper passes through the fourth head printing section. By doing this after the
The sequence is such that the next sheet is not delivered to 01. This is calculated by calculating the time required for the trailing edge of the paper to pass through the fourth print head, taking into consideration the length of the paper being conveyed in the feeding direction (registration roller pair 415).
, 416 by a timer means.

The above is the operation from the start of recording to the end of printing and ejecting the paper. When the set number of copies have been recorded, as shown in Figure 6 (
As explained in (e) and (f), the head-up and then unit-close operations are carried out, and finally the capping state is reached as shown in Fig. 3, ending the series of recording operations. mode and the third mode, power is applied to the heating element A200, the heating element B201, and the fan 203 so that the trailing edge of the paper is connected to the paper ejection roller pair 20.
It is shut off when it passes 1.212. This timing is performed by a sensor 213 that is linked to the arm 214 and detects the passage of the leading edge of the paper. This is the 19th
The subroutine paper discharge operation is shown in the figure.

Step 5 shows how the recording operation is repeated until a predetermined number of sheets are completed.

Next, the above-mentioned ejection failure prevention sequence (step 6 in FIG. 13) will be explained using FIGS. 19 and 21, which are flowcharts of the head control sequence.

As mentioned above, when the power is turned on to the apparatus, an ink circulation recovery operation is performed in consideration of the case where the apparatus has been left in a non-recording state for a long time. Thereafter, the device waits in the capping state until a recording start signal is input, but during this time, when the fixation timer means is activated, the circulation recovery operation is performed again. This fixed timer means prevents ejection failure due to increase in ink viscosity when the non-recording state continues for a long time even after the power is turned on.The time set for the timer varies depending on the characteristics of the ink and the environment in which it is used. However, it is on the order of several hours.

Next, when a recording start signal is input, a blank discharge operation is performed, and then the head is lowered to perform printing.

If the ejection timer is activated during recording, the head is raised to perform a dry ejection operation, and then the head is lowered to continue recording. The above-mentioned ejection timer is used to prevent ejection failure from nozzles that are not used for recording, in case not all nozzles are ejecting during recording. It is something to do. This is to recover from a minor discharge failure using a dry discharge means, and is a relatively short period of time on the order of several minutes. When the set number of images have been recorded in this way, the head down state is maintained for a certain period of time set by the output timer, and the apparatus waits for an input signal to start the next recording. If the signal to start recording is not input within the set time of the emitting timer, the head is raised, the unit is closed, and the unit enters the capping state. If a recording start signal is input within the set time, recording is started immediately and the image recording sequence described above (this is shown in the flowchart of FIG. 21) is taken. Here, a send-remaining timer can be substituted for the send-timer. The remaining timer is the time from the previous empty discharge until the end of image recording, which is subtracted from the output timer time, because it is the standby time when the head is in a head-down state and is not capped. , is set to be slightly shorter than the calculated subtraction time considering that ink dries easily.

〔Effect of the invention〕

As explained above, the present invention increases ink absorption and fixing/drying time by switching the drive frequency of the print recording head and paper conveyance speed to be lower than normal recording when recording an image on OHP paper. Eliminates ink overflow and smearing, allowing you to obtain images with great depth when fixed and dried.

Although recording on OHP paper has been described as one of the embodiments of the present invention, the gist of the present invention is to obtain the effect of recording images on paper that has slow ink absorption, slow fixation, and is difficult to dry. This method is effective not only for OHP paper but also for recording paper having the above characteristics.

[Brief explanation of the drawing]

1 is a schematic sectional view of an inkjet recording apparatus according to an embodiment of the present invention, FIGS. 2(a) and 2(b) are sectional views of main parts of the head recovery system in FIG. 1, and FIG. FIG. 4 is a cross-sectional view of the recording head in the capped state; FIG. 4 is a cross-sectional view showing the idle discharge operation of the head in FIG.
Figures (1) to (4) are state diagrams showing ink pressurization circulation operation;
6(a) to 6(f) are state diagrams when the recovery system enters the printing state from the standby state shown in FIG. 3, and FIG. 7 is a detailed sectional view of the belt conveyance section in FIG. 8 is a detailed cross-sectional view of the fixing/paper ejecting section in FIG. 1, FIG. 9 is a flowchart showing the sequence of head control, FIG. 1 shows a configuration diagram of an inkjet recording apparatus in which a recording head is arranged. FIG. 13 is a flowchart of the entire embodiment of the present invention, and each of FIGS. 14 to 21 is a subroutine flowchart of the flowchart in FIG. A flowchart of a recording operation, a paper ejecting operation, and a heating element control fixed timer is shown.

Claims (2)

[Claims] (1) A control device that can change and control the driving frequency of the inkjet heads and the conveyance speed of the conveyance means in an inkjet recording apparatus having a plurality of inkjet heads and a conveyance means provided at a position facing the inkjet heads and conveying a recording member. An inkjet recording device comprising: (2) The inkjet recording apparatus according to claim (1) has a mode of printing and recording on general paper and OHP (overhead projector) paper as the recording paper, and when printing on OHP paper, the head An inkjet recording apparatus characterized in that the driving frequency and the conveying speed of the conveying means are changed and controlled by the control device from those of the general paper.