JPH02179752A - Ink jet recorder - Google Patents

Abstract

PURPOSE:To enhance reliability of high image quality by a construction wherein a recording head part can be turned, and an opening part at the time of the turning is located on the upstream side with respect to a recording material feeding direction. CONSTITUTION:A driving force of a head unit-driving motor 26 is transmitted through a gear 27 to a head frame 28. The frame 28 can be turned on a turnable shaft l. At this time, a recording paper is fed rightward on a feeding belt. Since a gap between a recording head and the feeding belt is narrow, jamming with the paper occurs comparatively frequently in the gap. To avoid this, a moving mechanism for the head part is provided with a center of turning on the downstream side with respect to a recording paper feeding direction. An ink jet recorder ordinarily comprises a fixing device on the downstream side with respect to the feeding direction of the head part, the head frame 28 is provided with a rail 29, and a head block 6 with the recording head 1 positioned thereon can be taken out and replaced, in one body with the head 1. Thus, it is easy to protect an ejecting surface of the head at the time of jamming with the recording paper, and to prevent an ink from being dried or solidified on the ejecting surface.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is used as an inkjet recording device having functions such as a facsimile machine, a copying machine, and a printer, and as an output device such as a multifunction device and a workstation having such functions. The present invention relates to an inkjet recording device.

[Conventional technology]

Non-impact recording methods have 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 these, the recording head used in the inkjet recording method, which discharges liquid using thermal energy, has a high density array of liquid discharge ports (orifices) for discharging recording droplets to 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 make it long and planar (two-dimensional), so it is easy to make multi-nozzles and high-density packaging, and it is also highly productive in large quantities. It is also possible to provide an inkjet recording head and an apparatus having the head that are inexpensive to manufacture.

In this way, using an electrothermal converter as an energy generation means,
An inkjet recording head manufactured through a semiconductor manufacturing process generally has a liquid path corresponding to each orifice, and applies thermal energy 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. 17 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. 18 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 figure, a recording head L101 similar to the aforementioned recording head is driven by a motor 1.
It is constructed integrally with a carriage 1214 that is reciprocated on the rail 1213a by the drive of the carriage 1216. Ink tank 1222Y, 1222M.

The ink contained in 1222C and 1222B is supplied into the recording head 1101 by pumps 1223Y, 1223M, 1223c, and 1223B. The recording member (recording paper) is conveyed along the platen roller 1212 and temporarily stopped. Then, the recording head 1101 is connected to the rail 121.
While moving forward along lines 3a and 1213b, ink is ejected to record an image. After recording an image for a predetermined paper width, the recording head 1101 moves to the rail 1213a again.

It moves back along 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-orifice and elongated to approximately 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. Above all, image quality, reliability, and durability.

Regarding the recovery operation (recovery system) of the head, which has a large effect on the lifespan, etc., especially with long multi-nozzle types, the absolute number of ejection ports increases, so it is necessary to ensure stable ejection from all ejection ports and prevent non-ejection. 2nd place becomes important. Therefore, the performance of the recovery system is so important that it determines the performance of the entire device.

Therefore, the present invention solves the problem that affects the performance of the recovery system when configuring an inkjet recording device that uses a multi-nozzle recording head that is long enough to cover the width of the recording paper, and achieves high image quality. The object of the present invention is to provide a highly reliable inkjet recording device that can be used for a long period of time.

[Means to solve the problem]

An inkjet recording device having a multi-orifice type elongated head according to the present invention has a configuration in which the recording head portion is rotatably movable, so that the opening portion when the head portion rotates is
It is configured to be located on the upstream side in the conveyance direction of the recording material.

〔Example〕

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

FIG. 1 is a schematic sectional view of an inkjet recording apparatus for explaining one embodiment of the present invention. First, the outline of the inkjet recording apparatus of this embodiment will be explained using FIG. In the figure, 301 is a scanner unit that reads a document and converts it into an electrical signal. A signal based on the converted signal is given to the recording head section 305 of the printer section 302 as a drive signal. Paper feed section 303
The recording paper, which is one of the recording members stored in the recording paper, is sent out 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 the recording paper is sent out to the tray 420 via the fixing paper discharge section 307. In addition, 30
Reference numeral 6 denotes a recovery cap section, which has a function to maintain the recording head section 305 in a state where printing is possible at all times. Each of the above configurations will be explained in detail below.

First, ink supply to the full-line elongated recording head used in this embodiment will be explained using FIG. 16. FIG. 16 is an explanatory diagram schematically showing the configuration of the long recording head and ink supply means, and 1601
1652 is a common liquid chamber in the recording head 1601, and 1653 is an ejection port for ejecting liquid arranged on a recording liquid ejection surface 1654. Therefore, the number of ejection ports 1653 of this embodiment is arranged in the same number as the recordable width of the target recording material, and each of the ejection ports 1653
By selectively driving a heating element provided in a liquid path (not shown) leading to the head, 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 as described above, when recording is performed, the solenoid valve 1
662 is kept in the open state □, and the supply tank 165
5, the recording liquid is replenished to the common liquid chamber 1652 by its own weight, and from the liquid chamber 1652 it is supplied to the ejection port 1 via a liquid path (not shown).
I am led to 653. 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 165
9 can be driven to send the recording liquid into the common liquid chamber 1652 through the circulation pipe 1661, and from the common liquid chamber 1652 through the first supply pipe 1657, the recording liquid can 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. The evaporation of the ink liquid in the liquid path and its attendant effects are avoided by sealing the air space at the joint part with ink vapor and bringing the space formed by the cap and the recording head to the saturated vapor pressure of the ink. Prevents increase in viscosity and drying of ink in the liquid path. However, in a low fA environment 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 in the liquid path from evaporating. In some cases, it may not be possible to prevent non-ejection or unstable ejection of ink from the ejection ports during printing after the printing pause period. In the present invention, the problem of whether or not ink is ejected for the first time after a pause is hereinafter referred to as the "starting 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.

If the ink dries out due to being left unrecorded for a long period of time, increasing its viscosity and causing it to stick to the ejection port and/or the inside of the liquid path, pressurized circulation of the ink will If the non-recording state is relatively short and the sticking state is slight, the head is rotated to a state where printing can be performed by a blank ejection operation.

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

In the ink sheet recording method, small droplets of a recording liquid called ink are emitted 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. Driving signals based on these 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 main parts of a printer section in an inkjet recording apparatus according to the present invention, respectively. The state of the recording head during the recovery operation will be explained using FIG. 2(a). Ic, IM, IY,
lBk is cyan, respectively.

This is an inkjet recording head to which inks of magenta, yellow, and black colors are supplied. 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, IM, IY, of each of these colors,
Near the ejection ports of the IBk, there are ink absorbers 3C and 3M for absorbing ink corresponding to the ejection ports of each head.
, 3Y, and 3Bk are arranged. Ink absorber 3C,
3M, 3Y.

38 is 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 1Bk. The ink absorbers 3C and 3Y in FIG. 2(a) are shown separated from the ejection surfaces of the recording heads IC and IY. In addition, ink absorbers 3M and 3B
k indicates the position where the recording heads IM and IBk are brought into contact with the ejection surfaces. 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.

In addition, an ink squeezing member 5 is provided near each ink absorber.
is provided, and the ink absorbed by the ink absorbers 3C, 3M, 3Y, and 38k can be squeezed out and dropped by a lever (not shown). Figure 2 (a
) shows a state in which the ink absorber 3Y of the yellow head IY is squeezed.

A head block 6 to which the recording heads IC, IM, IY, and IBk are fixed is removably inserted into the block stay 9 via a rail 15. Further, this block stay 9 can rotate integrally with the head block 7 and each color head about the rotation center N as an axis. 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, LM, IY
, lBk, and the ink absorbers 3C, 3M, 3Y
- The ink absorbed and recovered by the ink 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.

FIG. 3(a) and FIG. 3(b) are schematic explanatory diagrams for explaining the recording head and positioning and fixing parts, respectively.
FIG. 3(a) is a schematic top view, and FIG. 3(b) is a schematic side view. In FIG. 3(a), 20.21 is a head fixing member, and the abutment portions 1a at both ends of the head l are
By being inserted into the abutting portion of the fixing member 20.21, the position in the direction of arrows A and B in FIG. 3(a) is changed, and the position in the vertical direction (direction of arrow C in FIG. 3(b)) is changed. is the positioning axis 18. It is determined by 19. Further, reference numeral 22 denotes a pressing pin, and the head inserted into the head fixing member 20.21 is brought into contact with the abutting portions 20a, 21a via the pressing pin 22 by the repulsive force of the spring 23, thereby positioning and fixing the head. is accomplished. Reference numeral 24 denotes an adjustment screw, which allows the position of each head to be adjusted in the direction of the arrow in FIG. 3(a), that is, in the direction perpendicular to the paper feeding direction (hereinafter referred to as "left margin").

25 is an eccentric piece for adjusting the head inclination direction.

In FIG. 3(a,), the position of each head in the direction of arrow B is moved by moving the head abutting portion 1a by the eccentricity l caused by rotating the top 25, and each head is adjusted independently. is possible.

With the above adjustment mechanism, the mounting position of each head can be easily adjusted. Therefore, it is easy to correct the deviation of images drawn in each color and record higher quality images.

Next, the moving mechanism of the head portion will be explained using FIG. 4. 26 is a head unit drive motor, and this motor is driven via a gear 27 to the head frame 28.
transmitted to. The head frame 28 can rotate in the direction of the arrow in the figure with the rotation axis l as the center of rotation. At this time, as can be seen from Figure 1, the recording paper is
The recording head is conveyed on the conveyor belt from the left direction in the figure.The gap between the recording head and the conveyor belt is, for example, 0.3 to 2,
The gap is very narrow (0 mm), and the recording paper is relatively often jammed in this gap. Therefore, the above-mentioned head movement mechanism has its rotation center located downstream in the recording paper conveyance direction. In other words, when the head is rotated, the opening is on the left side of the drawing, that is, on the upstream side in the conveyance direction, so even if a jam occurs in this area, the entire head will rotate and the upstream side will be the opening. This prevents jammed paper from getting stuck in the head portion and damaging the ejection surface of the head, as well as preventing ink from sliding.

At the same time, in an inkjet recording apparatus, the fixing device is usually located downstream of the head section in the conveying direction. Therefore, if the structure of the present invention has an opening on the upstream side, the effects of warm air and high temperatures from the fixing device can be minimized, the head ejection surface can be protected, and the ink can dry and stick. It is possible to prevent discharge failure. Also, head frame 2
8 is provided with a rail 29 for inserting and removing head blocks, so that the head block 6 on which the head l is positioned and mounted can be taken out and replaced integrally with each recording head l. To remove and insert the head block 6, the head frame 28 is inserted into a notch (
(not shown). There are four stopping positions of the head frame 28: (1) recovery position, (2) printing position, (2) retreat position, and (2) head unit attachment/detachment position. Fourth
Figures (a) and 4(b) show the recovery position.

■ The retracted position is the retracted position of the recording head section 305 when moving the recovery container 2, as will be described later in FIGS. 12(b) and (e), and ■ the printing position is as shown in FIG. 12(d). This is the head-down position, which will be described later. In the present invention, the (1) retracted position and (2) head unit attachment/detachment position are configured to be the same position. Detection of each of these positions is performed accurately by shielding light from the detection portions of the sensors 51 arranged corresponding to the respective stop positions by a light shielding plate 52 provided on the head frame 28.

FIG. 4(b) shows an example in which a worm decelerator is used in the drive section of the head moving mechanism described above. 59 is warm, 6
0 is the worm wheel. As a result, the head frame 28 can only be moved by driving from the motor side due to the characteristics of the worm decelerator, and the head frame itself will not naturally fall due to the weight of the plurality of heads mounted in the head frame. There will be no accidents (
Furthermore, it is also possible to fix the position of the head frame at the position where the motor is stopped.

FIGS. 5(a) and 5(b) are schematic side views of main parts for explaining the drive mechanism of the head recovery device, and are the same as FIGS. 4(a) and 4(b) described above. It shows the state seen from the side. FIG. 5(C) is a schematic partial enlarged view of the left side portion of the drive mechanism of the recovery device shown in FIG. 5(a) when viewed from the back side.

In these figures, 30 is a motor for driving the recovery device, and the drive of the motor is transmitted to a drive screw 37 via gear trains 31 to 36. The drive screw 37 converts the driving force transmitted from the motor 30 into linear motion, and the linear motion of the screw nut 38 meshed with the drive screw 37 moves the recovery container 2 from the recovery position, that is, the capping position, to the retracted position. move it.

The nut holder 39 engaged with the screw nut 38 and the recovery container 2 are connected by a connecting pin 40, and the motor 3
0 enables reciprocating movement of the recovery container 2.

Further, two arm portions 41 and 42 (the opposite side is not shown) are rotatably supported on the front and rear sides of the recovery system container 2, respectively. The arm portion 42 has rollers 45 (
The opposite side (not shown) is rotatably supported. on the other hand,
A unit side plate 47 facing the arm portion 42 of the recovery container 2
(The opposite side is not shown) is provided with a roller 45a (the opposite side is not shown). Note that rollers similar to the rollers 45 and 45a are also provided on the arm portion 41 side. Also, the rail 48 is provided with a groove into which the recovery container 2 is reciprocated. 49 are provided on both sides of the recovery container 2, respectively. Further, each of the arm portions 41 and 42 is provided with a torsion coil spring 44 so that each roller is urged against the groove of the rail. The rotational force of the motor 30 is transmitted through gear trains 31 to 36. Screw 37. Natsu 38. This is transmitted to the arm portions 41 and 42 via the nut holder 39 and the connecting pin 40, and is converted into a reciprocating motion of the recovery container 2. At this time, the rollers 45, 45a rotatably attached to the arm portions 41, 42 are urged along the grooves provided in the rails 48, 49 by the repulsive force of the torsion coil spring 44. (moves loosely along the line. Therefore, 1
) - It is possible to cause the recovery container 2 to move with a desired trajectory depending on the shape of the wheels 48 and 49. Like this,
Since a plurality of rollers for moving the container 2 are used for one arm, the load caused by the container 2 is distributed.
Therefore, the container 2 can be moved smoothly. Furthermore, since the arm portions and rollers are provided on both sides of the container 2, only one screw is required to drive the container 2, and the driving force can be transmitted smoothly enough. The stopping positions of the recovery container 2 are a recovery position 2a and a retracted position 2b, and at each position, a light shielding plate 50 attached to the nut holder 39 is connected to a sensor (photointerrupter) arranged corresponding to each stop position. ) This is done accurately by shielding the detection section 51 from light.

Next, capping with a cap and empty discharge.

A recovery mechanism such as pressurized ink circulation will be explained.

FIGS. 6(a) and 6(b) are schematic side views for explaining the cap driving section of the recovery device according to the present invention.

Figure 6(a) shows the time when the absorber is detached from the ejection surface of the head.
FIG. 6(b) shows the absorber in contact with the ejection surface of the head. 60 is a cap drive motor, and the drive of this motor is transmitted to the rack shaft 65 via gear trains 61 to 64, and further to the cap drive slide arm 68 via members 66 and 67. This slide arm 68 is slidable along a slide pin 72.

The reciprocating movement of the slide arm 68 is converted into the vertical movement of the absorbent guide 7 by the rotating arm 69 that moves the cap up and down. The ink absorbers guided by the absorber guides 7 are each held by absorber stoppers 71, and slide pins 72 provided at both front and rear ends move up and down along guide portions 73a provided on the cap side plates 73. configured to be possible.

With this configuration, the driving force of the motor 60 is transmitted as the driving force for bringing the ink absorber 3 into contact with and separating from the ejection surface of the head l. Further, detection of the position of contact and detachment is performed by detecting the position of the detection member 65a attached to the rack shaft 65 using microswitches 80 and 81 provided in the recovery container 2.

Next, one preferred embodiment of the squeezing mechanism for the ink absorber of the recovery/cap section of the present invention will be described. 7th
FIG. 7(a) and FIG. 7(b) are schematic explanatory views for explaining the ink absorber squeezing mechanism of the recovery device according to the present invention, and FIG. 7(a) shows the standby state, FIG. 7(b) shows the absorber when it is squeezed. Reference numeral 60 denotes an aperture drive motor, which in this embodiment also serves as the aforementioned cap drive motor. The driving of the cap mechanism and the diaphragm mechanism is transmitted by switching the driving with an electromagnetic clutch (not shown). The drive transmitted by a clutch (not shown) is transmitted to the aperture drive cam 79 via gear trains 75 to 78. Here, the rotation of the cam 79 is converted into a reciprocating motion of the slide arm 82.

The slide arm 82 is capable of linear movement along a slide pin 83 provided on the side plate of the cap, and is thereby further transmitted to the ink absorber squeezing member 5 via the lever 84 to absorb the ink absorber 3. By suppressing and deforming the body toward the guide 7 side, it is possible to squeeze out the ink that has soaked into the ink absorber and make it fall (7th
Figure (b)). Further, the aperture members of each color are connected by a connecting bar 86, so that the drive from the motor can be transmitted to all colors at the same time.

In the apparatus of this embodiment, the aperture mechanism is controlled to operate when the aforementioned cap, that is, the ink absorber 3 is removed from the head ejection surface, and the aperture mechanism is detected by a cam 79 provided on the cam 79. This is done by detecting the rotation of the cam with the microswitch 87. Normally, one rotation of the cam, that is, one time of aperture, constitutes one operation.The ink absorbing body 3, whose ink absorbing power has been increased again by these aperture operations, It is brought into contact with the ejection surface of the head again to perform complete cleaning.

Next, a mechanism for wiping the head ejection surface will be described. 8th
FIG. 8(a) and FIG. 8(b) are schematic explanatory views for explaining the head ejection surface wiping mechanism of the recovery device according to the present invention, and FIG. 8(a) shows the standby state, FIG. 8(b) shows the driving state.

In this embodiment, a cleaning blade 88 is used to wipe the head ejection surface. Reference numeral 60 denotes a blade drive motor, which also serves as the ink absorber diaphragm drive motor mentioned above in this embodiment, and also in sequence:
Since it is driven in conjunction with the diaphragm drive, the drive of only the wiping mechanism is not particularly changed. Similar to the aperture drive described above, the drive of the motor 60 transmitted to the cam 79 via the gear trains 75 to 78 is transmitted to the blade drive slide arm 90. The slide arm 90 is capable of linear movement along a slide pin 91 provided on the side plate of the cap, which further allows the blade rotation arm 9 to move in a straight line.
2, and the blade 88 mounted on the blade stand 93 interlocked with this is rotated about the shaft 94. Needless to say, this center of rotation is selected at a position where ink droplets, fixed ink, or dust adhering to the head ejection surface can be efficiently wiped away. As described above, the driving source is the same as that for driving the ink absorber aperture, and the blade is similarly configured to be driven when the ink absorber is separated from the head ejection surface. Detection is also performed by a microswitch 87 provided on the cam 79 in the same way as the aperture drive.
The ink absorber aperture drive and blade drive are performed by a motor 60.
This is simultaneously performed in a state where the ink absorber 3 is separated from the head ejection surface by driving.

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. 9 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.

lBk 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 3Bk are arranged, 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 IC, LM, IY, and IBk are covered by the ink seal 4, the partition plate 8, and the ink absorbers 3C, 3.
M, 3Y,: Surrounded by Hlk, maintains a moderately moist state,
It is possible to prevent the head discharge port from drying out. As described above, capping prevents ink from not being ejected when the recording head is at rest or on standby, and also protects the ejection ports and prevents dirt and the like from adhering to or entering the vicinity of the ejection ports.

Next, (1) preliminary (empty) ejection operation will be explained. 1st
Diagram O is a schematic diagram showing the idle ejection operation. Similar to the above-described capping operation, the ink absorbers 3C, 3M, and 3Y are held with a certain gap from the ejection surface of the capped recording head.

For 38k, an arbitrary number of ink ejection pulses are applied to the ejection energy generating means of all the print heads IC, IM, IY, and IBk. 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. FIGS. 11(1) to 11(4) are schematic diagrams showing the operation of the recovery/cap section 306 when performing an ink pressurization circulation operation in the ink supply system as an ink discharge operation. The operations in the recovery/cap section 306 include (1) normal capping, (2) pressurized ink circulation, (3) absorbent squeezing/wiping,
(4) Absorber contact - There are cycles (1) to (4). (1) to (4) in FIG. 11 correspond to these.

First, (1) capping refers to the aforementioned capping, which 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 38k 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. This allows the ink to circulate through the ink supply system through the inside of the head, removing internal air bubbles, and also expelling pressurized ink from the ejection port.This prevents it from sticking to the ejection surface. The ink ejected from the head ejection port is removed together with the ejected ink, and the vicinity of the ejection port is cleaned.As mentioned above, the ink ejected from the head ejection port is absorbed by the ink absorber: 3 (3C) which is in contact with the ejection surface.
, 3M, 3Y, 3Bk) without leaking to other parts (the ink that is absorbed and exceeds the maximum saturation amount in the absorber falls into the recovery container 2 through the absorber due to its own weight, The ink is guided into the waste ink tank (not shown) by the waste ink hose 12 through the waste ink tube 13.The pressurized circulation time at this time, that is, the pressurization time of the supply pump, is usually shortened due to the efficiency of removing stuck ink and air bubbles. 0.
It is preferably about 5 seconds to several seconds.

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 Kanehou 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 12(a)~
(f) is a state diagram when printing operation is started 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, the 12th
The state shown in FIG. 2B is the head-up state, 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 is retracted toward the upper right in the figure. This state is (c) unit oven, and after this state, (d) head down is performed. As a result, as shown in FIG. 12(d), the head is placed in a printable state (position), and the recovery system container 2 is placed in the retracted position. In this state, recording paper is passed from the right side in the figure with a constant gap kept from the head ejection surface, while the head IC, IM,
Image signals are input to IY and IBk, ink is ejected, and printing is performed on recording paper.

When the print on the recording paper is completed, that is, the head has finished discharging the ink, the head is moved up again as shown in FIG. 12(e), and then the head is recovered as shown in FIG. 12(f). The system container 2 is moved to the head side position, and the 12th
The printer enters the state shown in Figure (a), that is, the cap state, and enters the standby state in preparation for the next printing. The above (a) to (f)
), a normal copy operation is performed.

In addition, the above-mentioned (1) ink circulation can be performed in (a) cap operation in this operation, that is, at a predetermined timing during standby operation, for example, when the power is turned on or every certain period of time, to increase throughput. It is possible to prevent a decrease in image quality and obtain a good image.

FIG. 13 shows the registration rollers (415, 4 in FIG.
16), the recording paper reaches the conveyor belt 101 along guide plates 417 and 418. The conveyor belt 101 has an insulating layer (preferably with a volume resistance of 1012 Ωcm or more) on the side where the recording paper is placed, and a conductive layer (with a volume resistance of 108 Ω cm or more) on the opposite side.
・It is desirable that it be less than cm. ) 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 transport bell l-101 reaches the grounded conductive roller 107, the recording paper and the transport bell)
Since the recording paper is maintained in close contact with the conveyor belt 101 by electrostatic attraction, the recording paper is closely attached to the conveyor belt 101 and moves together 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 and recording heads IC, LM, 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 101. There is. Further, the platen 115 is provided with a pin 116,
The platen 115 is moved by the spring 117 and the guide bin 118.
is pressed and supported on the recording head section 305 side. In the recording area, set the distance between the recording heads IC, IM, IY, LBk and the recording surface of the recording paper by 100% to the desired setting value.
In order to obtain high-quality image recording, it is desirable to maintain accuracy on the order of μm. For this purpose, the platen 115 is arranged so that the platen 115 is placed 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. 5 is kept within several tens of μm.

Further, the recording heads IC, LM, 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 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 accuracy between the recording surface of the recording paper and the ejection orifice surface of each recording head in the recording area is improved. is kept within a desired range relative to the set point.

When the recording paper passes through this recording area, the recording head IC,
Images are recorded in sequence according to recording information using IM, 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 lot, the drive roller 10
The outer diameter deflection of the conveyor belt 101, the rotational precision of the drive motor, etc. are kept within desired ranges, and the speed fluctuation of the conveyor belt 101 is made sufficiently small so that there is 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 101 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 was shown in which the transport bell I-101 had a two-layer structure having an insulating layer and a conductive layer.
The conveyor belt 101 includes an insulating layer having a desired volume resistance.
It may be a layer, or it may have a multilayer structure of 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 configuration and physical properties of the recording member, but also varies depending on the external atmosphere. ,・The rate of natural fixation cannot be shorter than a certain time due to physical characteristics.

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
A halogen heater is used for the recording members 210, . 41 to heat the recording surface of the recording member 210 in a non-contact manner. The recording member 210 is attached to the conveyor table 20 due to ink adhesion.
Even when the recording member 210 rises from the recording member 2 and causes curling peculiar to inkjet printing, the fan 203 sends out warm air downward, so that the recording member 210 is reliably transported along the high-temperature conveyance table 202. 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 this apparatus will be explained using the diagrams of FIGS. 1 to 2, FIGS. 9 to 15, and flowcharts of FIGS. 19 to 27. 20 to 27 show subroutines of the flowchart of FIG. 19.

First, when the inkjet recording device is powered on, the first
As shown in the state diagram in Figure 1, <(1) Capping, (
After a series of operations including 2) ink pressurization circulation, (3) absorber squeezing, and (4) absorber contact (subroutine of FIG. 20: ink pressurization circulation operation), the system returns to the (1) capping state again. As a result of this series of operations (Step 1 in Figure 9), the device is stopped for a long time before the power goes out, and the ink thickens (
It is possible to prevent ink from not ejecting due to sticking due to drying (that is, increase in viscosity due to evaporation of the solvent) or generation of bubbles.

(1) Capping, (2) Pressurized ink circulation, (3)
) The series of operations following absorber squeezing, (4) absorber contact, and (1) capping is hereinafter referred to as ink pressurization circulation operation, but this ink pressurization circulation operation is not executed only immediately after power is turned on. do not have. For example, if the ink is used in a high-temperature or high-humidity environment where it is likely to thicken, or if the power is turned on, it may be left unused or left unused for a long time, which may cause problems such as sticking and foaming. , for a certain period of time using a timer, etc. (within an allowable time period in which the above problems do not occur, hereinafter referred to as cycle time)
This problem is solved by performing the above-mentioned ink pressurization circulation operation every time. 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. 9 is maintained. When the recording start signal is input, as explained in FIG. 10, a blank discharge operation is performed in which a certain 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 FIG. 19 as step 2. 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. , so that all the nozzles of the head can eject only by a dry ejection operation.This dry ejection operation is performed as shown in FIG. 12 ( a)-(d)
As shown in FIG. 2, the unit oven operation is performed in which the head moves to three directions and retreats, and then retreats to the upper right direction of the recovery container 2. This operation is shown in FIG. 22 as a subroutine: unit open operation. Subsequently, the head section 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 101 (
Perform a head-down motion. This is shown in step 3 of FIG. ). The head section 305 is a head block 6
an abutment surface (not shown) provided on the platen 115
The platen 115 comes into contact with a pin 116 provided above and stops at a position where the platen 115 is pushed down slightly against the spring 117 pushing it up. The stop position is detected by a printing position detection sensor and the printing 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, and due to the characteristics of the angle of progression, the head section 305 is pushed up by the reaction force of the spring 117. It is possible to maintain a stopped state without any trouble. The head is now ready for printing. Next, a paper feeding operation is performed, and as shown in the subroutine flowchart of FIG.
A pair of register rollers 415 which is fed by a pair of register rollers 2 and stopped after passing through conveyance rollers 413 and 414 and a guide section 419.
, 416.

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, 41B. 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 IO1 is brought into close contact with the surface of the conveyor belt 101 in order from its tip by electrostatic adsorption force, and the recording heads IC, IM, IY, IBk
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 conveyance belt 101 to the guide 213, the diameter of the drive roller 102 is set to be relatively small (the stiffness of the paper is The diameter of the drive roller 102 is such that the distance traveled by the surface of the belt lO1 that is frictionally driven by one rotation of the drive roller 102 is equal to the distance between the first head IC and the fourth head IC. head lB which is the th head
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 101 would be driven by one revolution 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, or of course 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 of 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 Coreha heating element B201 to rise to the set temperature.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 lengthened, and the paper will be heated to the fixing unit 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. 26 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 case of an operational error, the first mode, plain paper mode, is the priority mode, and the second mode, coated paper mode, is the priority mode (unless selected by the operator). The fixing auxiliary means is activated.Therefore, even if an image compatible with coated paper is mistakenly printed on plain paper, it is possible to prevent the problem of offset of ink to the discharge roller 211, which will be described later, and disturbing other recording papers.

Furthermore, this device has a third mode shown in Fig. 26, which is an overhead projector film (OH
P) Paper (film) mode.

0) The IP paper used in this device is coated with 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. be. 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 during the complicated printing time, problems such as image disturbance and offset may occur. To prevent this problem, increase the time for overlapping the next image to allow time for the ink to be absorbed.Also, to prevent offset etc., increase the time from printing to contacting the image surface. It is conceivable that the fixing means should be intervened in between. In this device, all conveyance speeds related to paper feeding, such as paper feed speed, belt conveyance speed, and ejection speed, are adopted in the first mode and the second mode. In addition to slowing down to a speed that solves the above problem (low speed mode) while keeping the same ratio, the head drive frequency is also changed at the same time to ensure that an appropriate image is printed. ,
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. The heating element B201 and the fan 203 are also powered on at the same timing as in the first mode to assist in fixing.

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 101. 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 slightly faster than the conveyance speed of the conveyor belt lO1. For example, if the conveying speed of the register rollers 415 and 416 is set to be slower than the speed of the belt 101, the paper is conveyed by the register rollers 415 and 416 and the receiver is passed to the belt 101. The paper is electrostatically attracted and held on its surface, but at the position where the first head starts printing, only a portion of the paper from the leading edge is still attracted.
At this time, the conveying force of the register rollers 415 and 416 overcomes the conveying force of the belt 101, and the register rollers 415 and 4
Since the paper is controlled by the conveyance speed of belt 101
As the conveyance progresses, the amount of paper 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, in this device, the roller pair 415
The conveyance speed of 416 degrees is set higher than the conveyance speed of 101 degrees, and the 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 pair 415.41
6 does not affect the conveying force of the belt 101. However, if the speed difference is set to a large value, the loop becomes large and the suction operation becomes unstable due to fluttering or the like. Therefore, the speed difference should be zero or very small to the extent that the speed difference does not reverse (experimentally, it has been found that a ratio of about 0-1.5% is good.Next, we will discuss the transport speed of the paper ejecting section. In a normal configuration, the belt 101 and the paper ejection roller 211 and 21 are arranged so as not to affect the conveyance speed of the belt, like the relationship between the pair of registration rollers and the conveyance belt described above.
However, in this apparatus, a heating element such as A200 serves as a fixing means on the downstream side of the belt conveying device 304, and also serves as a guide, and the paper is transported to this conveying table 2.
Since the paper is heated from the back side along the surface of the conveyor table 202, if a loop is formed here, the paper will not be able to follow the surface of the transport 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 1O1, so that the paper does not form a loop. Further, at this time, the conveyance platform 200 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 21+ and 212.
A paper transport surface is set, and when the leading edge of the paper is sandwiched between the paper ejection rollers 211 and 212, the paper is further transferred to the transport table 2.
It is conveyed along the 02 surface. Here, the paper ejection roller 211. The conveyance force of the belt 101 is greater than the paper suction force of the belt 101 (the paper ejection rollers 211 and 21 are
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 bell l-101 (the wow-flush of conveyance) must be carried out with sufficient consideration to the accuracy of the outer diameter of the belt 101, the thickness accuracy of the belt 101, etc. In addition to these factors, consideration must also be given to things that cause disturbance to the conveying section 304 and cause wow and flutter, and in this apparatus as well, the paper sent out from the register rollers 415 and 416 is placed on the belt lO1. When the uke is handed over, as mentioned above,
The conveyance speed of register roller pair 415 and 416 is 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.

In order to prevent this problem, when recording images continuously in this device, the timing for passing the paper onto the bell) 101 is set so that the trailing edge of the previous paper has passed through the fourth head printing section. By doing this later, the belt 10 is
The sequence is such that the next sheet is not transferred to No. 1. This is calculated by calculating the time required for the trailing edge of the paper to pass through the fourth head printing section, taking into consideration the length of the paper being conveyed in the feeding direction, and calculating the time required for the trailing edge of the paper to pass through the fourth head printing section.
This is done by a timer means based on the ON signal of 416.

The above is the operation from the start of recording to the end of printing and the ejection of paper. When the set number of copies have been recorded, the head is raised, and then the unit is The closing operation is performed, and finally the capping state is reached as shown in Fig. 3, and the series of recording operations ends.Here, if recording is being performed in the first mode and the third mode, the heating element A200 and heating element B201
And the fan 203 is energized when the trailing edge of the paper is the paper ejection roller pair 2.
It is shut off at the timing when it passes 11,212. 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 second
The subroutine paper ejecting operation is shown in Figure 5.

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. 19) will be explained using FIG. 15 and FIG. 27, 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 signal to start recording is input manually, and during this time, when the fixed 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. 27) 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 slightly shorter than the calculated subtraction time considering that ink dries easily.

〔Effect of the invention〕

As described above, in the inkjet recording apparatus having a multi-orifice type elongated head according to the present invention, the head portion that performs recording is configured to be rotatably movable, so that the opening when the head rotates is moved in the recording material conveyance direction. By arranging it on the upstream side, it is possible to protect the head ejection surface in the event of a recording material jam, simplify the handling of jammed paper, and prevent ink from drying on the head ejection surface due to the heat of the fixing device, which is normally installed on the downstream side. It has many excellent effects such as preventing sticking.

[Brief explanation of the drawing]

FIG. 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 essential parts of the head recovery system in FIG. 1, and FIG. ). Figure 6(a). Partial explanatory diagram, Fig. 7(a). (b) and (c) are detailed views of the recovery system drive unit (b) are the recovery system cap drives (b) are the recovery system ink absorber aperture drive units, respectively. Fig. 8 (a), (=c-) 9 is a cross-sectional view of the recording head in a capped state in FIG. 2, FIG. 1O is a cross-sectional view showing the idle ejection operation of the head in FIG. 2, and FIG. Fig. 12 is a state diagram showing the ink pressurization circulation operation, Fig. 12 is a state diagram when the recovery system enters the printing state from the standby state shown in Fig. 9, and Fig. 13 is a detailed cross section of the belt conveyance section in Fig. 1. Figure 14 is a detailed sectional view of the fixing and paper ejection section in Figure 1; Figure 15 is a flowchart showing one sequence of head control; Figure 16 is the configuration of the elongated recording head and ink supply means. FIG. 17 is a schematic configuration diagram of a conventional inkjet recording head, FIG. 18 is a configuration diagram of an inkjet recording apparatus in which a conventional recording head is arranged, and FIG. 19 is an overall diagram of an embodiment of the present invention. In the flowchart, the second
0 to 27 are subroutine flowcharts of the flowchart in FIG. 19, and the ink pressurization circulation operation,
A flowchart of a dry ejection operation, a unit oven operation, a paper feeding operation, a recording operation, a paper ejection operation, a heating element control, and a fixation timer is shown. Cow P Soph. Pressure Fig. 11 Squeezing/wiping contact Fig. 12 Erector (No change in content) Kanf or sword (text 41Z) Dimensions of sword roll name 111 help, 20th size of flute seal, mouth of earth pressure, work of safur÷, 4th stroke of paper) Bui size Furuko〉 Unit Otsubushi 1 to 222 Full hand sampler file Mr. Ichikawa's child Toy lower frame 250 Conference timer layer 270 Suffle〉 Hatsume Misaki 3 Ihon Ibli wholesale bag 26 Stomach sales volume 1 + (method) % formula % Name of the invention Relationship with the person who corrects the ink sheet recording device case

Claims (1)

[Claims] (1) In an inkjet recording device that performs recording by ejecting ink from an ejection port onto a recording surface of a recording material, the inkjet head for performing the inkjet recording is rotatable around a rotation center; ,
An inkjet recording apparatus characterized in that an opening of the rotating section is configured to face upstream in a recording material conveyance direction.