JPH05147219A - Ink jet recording device - Google Patents

Abstract

PURPOSE:To provide a compact ink jet recording device with a high recording action throughput. CONSTITUTION:The ink jet recording device is composed of recording heads 101a to 101d which liquefies solid ink with a higher than room temperature melting point, discharging the liquid, a discharge control part which outputs a discharge signal complying with an image at a specified timing, to the recording heads 101a to 101d, a rotating drum 108 which transports cut recording sheets 109 sequentially at a specified transport interval, in synchronization with the discharge signal so that the sheets run opposite to the recording heads 101a to 101d, and a blade 118 for removing ink which sticks to the rotating drum 108. A discharge control part applies an unloaded discharge signal which enables an ink discharge to be simulated for purposes other than for recording an image, to the recording heads 101a to 101d, during a recording operation, so that an unloaded discharge is performed on a position where the recording sheet 109 is not present on the rotating drum 108.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for ejecting ink droplets for recording, and more particularly to an ink jet recording apparatus for liquefying and ejecting solid ink.

[0002]

2. Description of the Related Art Conventionally, as this type of ink jet recording apparatus, a serial scan type recording apparatus for recording by ejecting ink by moving a recording head over the entire recording width of recording paper, and recording paper There is known a line type recording apparatus including a full line type recording head in which ink ejection ports are formed over the entire maximum recording width.

As a serial scan type recording apparatus,
As shown in FIG. 7, a recording medium 709 wound around a rotary drum 708 is adsorbed and held, and the circumferential direction is used as a recording line, and the recording head is moved for each recording line to perform recording. Then, as shown in FIG. 8, a recording paper 809 is sandwiched between a pair of rollers 808 and 811, and is held in a planar shape with respect to the recording head 801, and ink is ejected while moving the recording head over its entire width. There is a flat conveyance type that performs recording by doing so.

In the case of the drum transport type recording apparatus shown in FIG. 7, the recording paper 709 wound around the rotary drum 708 has a front end and a rear end regardless of whether the recording is monochromatic recording or color recording. It is only the time when the portion where the recording paper does not exist faces the recording head 701. Also,
In the planar transport type recording apparatus shown in FIG. 8, a large number of recording heads ejecting inks of different colors may be combined in order to realize a color image. In that case, one of the reciprocating movements of the recording heads is performed. Only the discharge operation can be performed. This is because the color tone will change for each recording line if the order of ink color application changes back and forth. Therefore, assuming a color printer, there is an advantage that the recording time of the drum-conveying type recording apparatus is shorter than that of the flat-conveying-type recording apparatus.

On the other hand, a line type recording apparatus is shown in FIG.
As shown in FIG. 4, four full line type recording heads 901a, 901b, 901 that eject ink of different colors are provided.
c, 901d so that they face the recording papers 905a, 90a.
There is a belt transport system in which 5b is sequentially transported by the recording paper transport belt 904. In this case, high-speed recording is possible because the time required for paper feeding and paper ejection is shorter than that of the above-described drum transport system.

As a problem peculiar to the above-mentioned ink jet recording apparatus, when the recording head is left in a non-ejection state for a certain time, the water content of the ink in the nozzle communicating with the ink ejection port evaporates and the viscosity of the ink becomes high. There is a point that it becomes impossible to eject.

Therefore, in the conventional ink jet recording apparatus, the recording head is moved from the recording position opposed to the rotating drum or the conveying belt to a predetermined blank discharge area other than the recording head at regular intervals, and the recording head is moved to a space other than the recording target. The ejection was prevented from becoming impossible. There is a problem of non-ejection even in an ink jet recording apparatus that uses solid ink and has a feature of recording on plain paper, and similarly, the non-ejection is prevented by performing the above-described blank ejection.

[0008]

However, the above conventional example has the following problems.

As the nozzle diameter of the recording head communicating with the ink ejection port is smaller, the viscosity of the ink in the vicinity of the ink ejection port rises in a shorter time, so that the time until nozzle non-ejection is shortened. In recent years, there has been a recording head in which a nozzle diameter becomes smaller as a higher-definition image is required and ejection failure occurs in a few seconds. With the method of preventing the non-ejection by performing the idle ejection by moving the head from the recording position facing the drum or belt to the idle ejection area as in the conventional example, it is necessary to move the recording head every few seconds, and as a result, the throughput is increased. It will fall significantly. In particular, in the case of a line type recording apparatus, an empty ejection area covering the width of the recording head is required to receive the ink ejected from the full line type long recording head, which leads to an increase in the size of the apparatus.

The present invention has been made in view of the problems of the above-mentioned conventional technique, and an object of the present invention is to provide a small-sized ink jet recording apparatus having a high throughput of recording operation.

[0011]

According to the present invention, a recording head for liquefying and ejecting a solid ink having a melting point higher than room temperature and an ejection signal corresponding to an image are output to the recording head at a predetermined timing. An inkjet recording apparatus comprising: an ejection control unit; and a recording paper conveyance unit that conveys a single piece of recording paper at a predetermined conveyance interval in synchronization with the ejection signal so as to face the recording head in order. The ejection control unit has an ink removing unit for removing ink adhering to the paper conveying unit, and the ejection control unit discharges the recording paper of the recording paper conveying unit to a position where no recording paper exists during the recording operation, except for the purpose of image recording. A blank ejection signal for performing the above is applied to the recording head.

Further, in the above-mentioned ink jet recording apparatus, the recording paper conveying means is composed of a rotary drum for holding the recording paper by electrostatic attraction, and the ink removing means is provided for a portion of the surface of the rotary drum where the recording paper does not exist. When the blade is in contact with substantially the entire width, when the recording paper conveying means has a conveying belt that holds the recording paper by electrostatic attraction and conveys it in a plane, and when the ink removing means is the conveying belt. In the case where the blade is in contact with substantially the entire width of the surface of the carrying belt on the side opposite to the recording head, the ink removing means is pressed against the surface of the surface of the carrying belt under pressure over the substantially entire width of the surface of the carrying belt. And a heating unit which is arranged upstream of the web in the moving direction of the conveyor belt and heats the conveyor belt. And if the discharge control unit, when the portion where the recording paper does not exist between the front and rear ends of the recording paper held by the recording sheet conveying means opposed to the recording head,
When outputting a blank ejection signal, when the recording head is mounted on a carriage that can move over the entire maximum recording width of the recording paper, and when the recording head has an ink ejection port over the entire maximum recording width of the recording paper. There is a case of a formed full line type, and a case of the recording head ejecting ink by utilizing thermal energy and having an electrothermal converter that generates the thermal energy.

[0013]

According to the ink jet recording apparatus of the present invention, during the recording operation, the blank discharge is performed to the position where the recording paper does not exist, so that it is not necessary to move the recording head for the blank discharge. Further, although it is considered that the ink is adhered to the recording paper conveying means due to the idle discharge, it is removed by the ink removing means, so that the recording paper and the image on the recording paper are not contaminated.

[0014]

Embodiments of the present invention will now be described with reference to the drawings.

First, a first embodiment of the ink jet recording apparatus of the present invention will be described.

FIG. 1 is a perspective view showing a first embodiment of an ink jet recording apparatus of the present invention.

The ink jet recording apparatus of this embodiment has four recording heads 101a, 101b and 10 for ejecting black, yellow, magenta and cyan inks, respectively.
1c and 101d are mounted on a carriage 102, and a recording medium 109 is attracted and held by a rotating drum 108 to face the recording heads 101a, 101b, 101c and 101d, and a color recording is performed while rotating. Recording device.

In the carriage 102, a wire 107 stretched between a motor pulley 105 connected to a carriage motor 104 and a tension pulley 106 is engaged, and the carriage motor 104 rotates, whereby 2 guides 10 in the direction of arrow A
It is possible to reciprocate along 3, 114 over substantially the entire maximum recording width of the recording paper.

The recording paper 109 is electrostatically attracted to the rotary drum 108 which is rotated in the direction of the arrow B by the drum motor 110, and the rotary drum 108 rotates, whereby the recording head 101a mounted on the carriage 102, 1
It is moved so as to face the ink ejection surfaces of 01b, 101c, and 101d. While the recording paper 109 is held by the rotary drum 108, the recording line extends in the circumferential direction, and one rotation of the rotary drum 108 completes the recording of one recording line.

Further, in the ink jet recording apparatus of this embodiment, a position (hereinafter referred to as a "capping position") facing the left end portion of the guides 103 and 114, which is outside the reciprocating range of the carriage 102 during the recording operation. Further, a cap 112 for preventing the evaporation of ink in the recording heads 101a, 101b, 101c, 101d is provided.

The cap 112 has a hollow structure, and has the recording heads 101a, 101b, 101.
Four openings 112a, 112b, 112c, and 112d are formed on the surfaces of c and 101d that face the ink ejection surface, the openings 112a, 112b, 112c, and 112d communicating with the hollow portion and having a shape corresponding to the shape of the ink ejection surface. The cap 112 is movable in the direction of arrow C, and when the power is turned off, the recording heads 101a, 101b, 101c, and 10c that face the cap 112 and stop.
The openings 112a, 112 are formed on the ink ejection surface of 1d.
The ink ejection surfaces are kept in a sealed state by pressing b, 112c, and 112d into contact with each other. Further, the cap 112 has a pump 115 connected to the hollow portion via an air tube 111, and the openings 112 a, 112 b, 112.
By operating the pump 115 in a state where c and 112d are in pressure contact with each ink ejection surface, a negative pressure can be created in the hollow portion. Furthermore, the cap 112 is
An ink discharge tube 116 that communicates with the hollow portion and a waste ink tank (not shown) is provided. By setting the hollow portion in a negative pressure state, the recording heads 101a, 101b,
The ink sucked from the ejection ports 101c and 101d is discharged to the waste ink tank. The cap 112 is provided with a heater (not shown), and the temperature of the entire cap 112 is raised by the heater to reduce the ink viscosity.

In this embodiment, the recording head 10 is also used.
A blade 118, which is an ink removing unit for removing ink droplets adhering to the rotary drum 108 by the ink ejecting operation from the ink la 1a, 101b, 101c, and 101d, is provided below the guide 103 (see FIG. 2).

The blade 118 is made of resin or the like, is rotatably supported in the direction of the arrow D about a support shaft 119, and is in contact with the rotary drum 108 over substantially the entire width thereof. .. The blade 118 stops at two positions, a contact position and a non-contact position, with respect to the rotary drum 108. Foreign matters such as ink drops removed by the blade 118 are stored in the ink receiver 120. The ink receiver 120 can be replaced if necessary.

Next, the recording heads 101a, 101b, 101c, 101d mounted on the carriage 102.
The configuration will be described with reference to FIGS. 3 (a) and 3 (b).

Recording heads 101a, 101b, 101
c and 101d are attached to a head support plate 117 which is vertically fixed on the carriage 102.

Recording heads 101a, 101b, 101
c and 101d correspond to the black, yellow, magenta, and cyan inks, respectively, and each have a density of 16 / mm and 64 nozzles that communicate with the ink ejection ports are formed. A heater for ejecting ink is provided in each nozzle, and each heater is energized according to an image signal, and ink is ejected by utilizing the bubbling in the nozzle at that time.

122a, 122b, 122C, 122d
Are print heads 101a, 101b, 101, respectively.
Ink tanks for storing black, yellow, magenta, and cyan solid inks corresponding to c and 101d. The ink tanks 122a, 122b, 122c,
The upper surface of 122d is approximately 1 from the orifice surface of each recording head.
It is set to 0 mm lower, which prevents ink from jumping out due to vibration. Ink tank 122
On the bottom surfaces of a, 122b, 122c and 122d, heaters 124a, 124b and 12 for melting ink are respectively provided.
4c and 124d are joined. Reference numeral 121 denotes an ink supply plate adhered to the head support plate 117, and ink supply holes 126a, 126b, 12 communicating with the four ink tanks 122a, 122b, 122c, 122d, respectively.
6c and 126d are formed. Head support plate 117
The ink supply holes 126a, 126b, 126c, 12
6d communicating with grooves 127a, 127b, 127c, 12
7d are provided, and the respective grooves 127a, 127 are provided.
The head support plate 117 is at the uppermost part of b, 127c, 127d.
Penetrates into the back of. The ink supply holes 126a, 1
Joints 123a, 123 are provided on 26b, 126c, 126d.
Ink supply pipe 125 through b, 123c, and 123d
a, 125b, 125c, 125d are connected,
The ink supply pipes 125a, 125b, 125c, 12
The other ends of 5d are recording heads 101a, 101b,
It is connected to 101c and 101d. Ink tank 1
The ink dissolved in the inks 22a, 122b, 122C, 122d is the ink supply holes 126a, 126b, 126c, 1
26d and the ink supply pipes 125a, 125b, 125c, 12 passing through the grooves 127a, 127b, 127c, 127d.
Moving to 5d, each recording head 101a, 101b, 101
c, 101d are supplied. The recording head 101
The heaters 128a, 128b, 128c and 128d are also joined to a, 101b, 101c and 101d, respectively, so that the nozzle portion can be heated.

Next, the operation of this embodiment will be described with reference to the flow chart shown in FIG.

First, when the power of the recording apparatus is turned off, the recording heads 101a, 101b, 101c and 101d are capped by the cap 112 at the capping positions described above.

In this state, when the power of the recording apparatus is turned on (step 401), the recording heads 101a, 101b,
101c, 101d heaters 128a, 128b, 1
28c, 128d and ink tanks 122a, 122b,
122c, 122d heaters 124a, 124b, 1
24c and 124d are driven (step 402), and the print heads 101a, 101b, 101c and 101d and the ink tanks 122a, 122b, 122c and 122d are heated.

At this time, the recording heads 101a, 101
b, 101c and 101d and ink tanks 122a and 12
The temperatures of 2b, 122c and 122d are respectively detected by temperature sensors (not shown), and the heaters 128a, 128b, 128c and 128 are heated until the respective temperatures reach 90 ° C.
Power is continuously supplied to d, 124a, 124b, 124c, and 124d. Then, the recording heads 101a, 101b, 10
1c, 101d and ink tanks 122a, 122b, 1
After the temperature of each of 22c and 122d reaches 90 ° C, the heater 1 is maintained so as to maintain the temperature of 90 ° C to 93 ° C.
28a, 128b, 128c, 128d, 124a, 1
The energization of 24b, 124c and 124d is controlled (step 403). In addition, the recording heads 101a, 101b, 10
Cap 112 capping 1c, 101d
As for the above, the temperature is controlled similarly to the recording heads 101a, 101b, 101c, 101d and the ink tanks 122a, 122b, 122c, 122d by energizing the above-mentioned heater.

Subsequently, the pump 115 is driven (step 404), whereby each recording head 101a,
Ink near the ink ejection openings of 101b, 101c, 101d is sucked out, and ink tanks 122a, 122b, 122c, are formed in the nozzles communicating with the respective ink ejection openings.
Ink is supplied from 122d. The ink sucked from each of the recording heads 101a, 101b, 101c, 101d is stored in the waste ink tank through the waste ink tube 116. The suction operation of the pump 115 is performed for 1 second, and then the cap 112 is retracted (in the direction of arrow C in FIG. 1) (step 405) to release the capping of the recording heads 101a, 101b, 101c and 101d.

Recording heads 101a, 101b, 101
After the capping of c and 101d is released, the recording heads 101a, 101b, 101c,
When the image signal is input to 101d, the recording operation starts (step 406).

Recording heads 101a, 101b, 101
When an image signal is input to c and 101d, one sheet of recording paper 109 is fed from a paper feed tray (not shown) (step 407) and electrostatically attracted to the surface of the rotary drum 108 (step 408). ..

When the recording paper 109 is electrostatically attracted to the rotary drum 108, the carriage 102 is guided by the guides 103 and 114.
Along the line to the first recording line position (step 409). Then, the rotary drum 108 rotates in the direction B in FIG. 1, and accordingly, the recording heads 101a, 1a
Recording is performed by ejecting ink of each color from 01b, 101c, and 101d, and recording of one line is completed when the rotary drum 108 makes one rotation (step 4).
10).

When the recording for one line is completed, the carriage 102 moves by 64 dots (4 mm) and stops at the next recording line position. During the movement of the carriage 102, the recording heads 101a, 101b, 10 are moved toward the gap between the front end and the rear end of the recording paper 109 of the rotary drum 108.
50 blank discharges from 1c and 101d are performed (step 411).

At this time, the blade 118 is attached to the rotary drum 1.
The ink that has been solidified by adhering to the rotary drum 108 by the idle ejection is removed by bringing the ink into pressure contact with 08 (step 412). As described above, in steps 410 to 412, the rotation of the rotary drum 108 and the carriage 10 are performed.
When the recording of one page of the recording paper 109 is completed by repeating the movement of one line 2 and the cleaning of the rotary drum 108 (step 413), the recording paper 109 is
The electrostatic attraction by the rotating drum 108 is released and the electrostatic discharge is discharged (step 414).

When recording of one page of the recording paper 109 is completed and paper ejection is completed, it is checked whether or not all recording is completed (step 415). If not completed, the feeding shown in step 407 is performed. The recording of the next page is performed by repeating the paper operation and thereafter. On the other hand, when all recording is completed, the rotation of the rotary drum 108 is stopped, the carriage 102 is moved to the capping position, and the recording heads 101a, 101b, 101 are moved by the cap 112.
Capping c and 101d (step 416).
Then, finally, by turning off the power source of the recording apparatus (step 417), the recording heads 101a, 101
The capping states b, 101c, and 101d are in a standby state until the next recording operation.

Next, the second embodiment of the present invention will be described with reference to FIG.
The description will be made with reference to (a) and (b).

FIG. 5 is a view showing a second embodiment of the ink jet recording apparatus of the present invention, (a) is a plan view and (b) is a side view.

The ink jet recording apparatus of this embodiment has four full line type recording heads 501 for ejecting cyan, magenta, yellow and black inks, respectively.
a, 501b, 501c, 501d, the recording paper is conveyed in order by the recording paper conveying belt 504.
This is a belt-conveyance type recording apparatus that performs recording while conveying so as to face 01a, 501b, 501c, and 501d.

The recording paper conveying belt 504 is a roller 50.
It is stretched between 6 and 507. Recording paper 505a, 50
5b is sandwiched between the roller 506 and a pair of pinch rollers 502, and placed on the recording paper transport belt 504 at predetermined intervals (20 mm in this embodiment). It The recording papers 505a and 505b placed on the recording paper conveyance belt 504 are the rollers 5
When 06 rotates in the direction of arrow E, the recording head 501
a, 501b, 501c, 501d are conveyed (direction of arrow F), and after the recording is completed, the rollers 507 and
It is sandwiched between a pair of pinch rollers 503 and discharged. Also in the case of the present embodiment, the recording paper is electrostatically adsorbed by the recording paper conveyance belt 504 and is smoothly conveyed without floating. A blade 508 for removing foreign matter such as solid ink adhering to the surface of the recording paper conveyance belt 504 is provided below the recording paper conveyance belt 504 and is always in contact with the surface of the recording paper conveyance belt 504. Has been. Further, below the contact portion between the blade 508 and the recording paper conveyance belt 504, an ink receiver 509 is provided for accumulating the foreign matter removed by the blade 508.

Recording heads 501a and 501 of this embodiment
b, 501c, and 501d are the recording heads 101a, 101b, 101c, and 101d used in the first embodiment described above.
Ink is ejected on the same principle as. Each of the recording heads 501a, 501b, 501c, and 501d has 3360 nozzles formed in a width corresponding to the recording sheet width of A4 size, and ejects at a timing of 16 shots / mm. Further, in the present embodiment, the recording heads 501a, 501b, 501c, 501d.
Is configured to perform idle discharge toward the recording paper conveyance belt 504 by utilizing the conveyance interval of the recording paper conveyed by the recording paper conveyance belt 504.

The operation of this embodiment will be described below.

First, the recording paper 505a is fed between the pinch roller 502 and the roller 506 by a paper feeding mechanism (not shown), and the recording paper conveying belt 5 passes between them.
It is placed on 04. After that, the recording paper 505a is conveyed in the direction of the arrow F as described above while being in close contact with the recording paper conveyance belt 504 by electrostatic attraction, and first passes below the recording head 501a that ejects cyan ink. To do. Ink is ejected when the recording paper 505a passes under the recording head 501a. After that, the recording heads 501b, 501c, and 501d that eject magenta, yellow, and black inks pass in order, and an image is formed thereby.

On the other hand, with the recording on the recording paper 505a, the second recording paper 505b is fed at a timing with a distance of 20 mm from the rear end of the recording paper 505a. Therefore, after the recording of the recording paper 505a is completed and before the recording of the next recording paper 505b is started, the recording heads 501a, 501b, 501c,
501d has a period in which no ejection is performed, but as described above, idle ejection is performed by using this period to prevent ink non-ejection due to nozzle clogging due to ink drying. In this case, the ink is adhered to the recording paper conveyance belt 504 by the idle discharge, but the ink is immediately solidified and is removed by the blade 508, so that the other recording paper, the roller, etc. It doesn't get dirty. After the recording is completed, the recording paper 505a is sandwiched between the pinch roller 503 and the roller 507, the curvature is separated, and the recording paper 505a is discharged into a paper discharge tray (not shown).

In the case of the recording apparatus having the full-line type recording head corresponding to the A4 width as in the present embodiment, the width of the recording head is about 250 mm, and the blank ejection is performed to the portions other than the recording paper conveyance belt. If an attempt is made, the size of the ink receiver for receiving the ink becomes large, and as a result, the size of the entire apparatus becomes large. Furthermore, in that case, it is necessary to move the recording head in a direction other than the recording paper conveyance belt, and the distance becomes long, so that it takes time and the recording throughput decreases. However, as in the present embodiment, the above-mentioned problems can be solved by performing the idle discharge on the recording paper conveyance belt by utilizing the recording paper conveyance interval.

Next, the third embodiment of the present invention will be described with reference to FIG.
The description will be made with reference to (a) and (b).

6A and 6B are views showing a third embodiment of the ink jet recording apparatus of the present invention. FIG. 6A is a plan view and FIG. 6B is a side view.

The ink jet recording apparatus of this embodiment is also equipped with four full-line type recording heads 601a, 601b, 601c and 601d, as in the case of the above-mentioned second embodiment. A belt-conveying recording device that conveys recording paper in order. Also in the case of the present embodiment, similarly, the recording heads 601a, 601b, 601c, and 601d perform idle ejection by utilizing the recording paper conveyance interval of the recording paper conveyance belt 604.

The ink jet recording apparatus according to this embodiment has the recording heads 601a, 601b, 601c and 601d.
The web 608 is provided for removing the ink adhering to the recording paper conveyance belt 604 by the idle discharge of. The web 608 is stretched around a web supply roller 609, a web winding roller 610, and a pressure contact roller 611. A motor (not shown) is connected to the web winding roller 610, and the rotation of the motor causes the web 608 to move in a direction opposite to the moving direction (direction G in the drawing) of the recording paper transport belt 604. Drive in the middle H direction). Further, a heater fan 612 that sends hot air to the recording paper conveyance belt 604 is provided on the upstream side of the web 608 with respect to the moving direction of the recording paper conveyance belt 604.

The ink removing operation according to this embodiment will be described below.

The heater fan 612 is turned on a few seconds before the ink adhering to the recording paper conveyance belt 604 due to the idle discharge passes over the heater fan 612, and the heated air liquefies the solidified ink. ..
After that, the liquefied ink comes into contact with the web 608 that is pressed against the recording paper conveyance belt 604 by the pressing roller 611 before being absorbed and removed. After absorbing the ink, the web 608 is wound by the web winding roller 610 by about 3 mm, so that the new surface is pressed against the recording paper conveyance belt 604. The heater fan 612 is turned off immediately after the ink ejected by the idle ejection passes. After that, similarly, the heater fan 612
Also, while the web 608 is intermittently operated, the blank discharge is performed together with the recording operation.

In the present embodiment, a large amount of ink can be absorbed by pressing the web 608 against the surface of the recording paper conveying belt 604 with one pressing roller 611, so that the ink discharged by the blank ejection can be applied to the ink receiver. The number of times of replacement is smaller than that of storing ink, and ink can be removed smoothly.

In each of the above-mentioned embodiments, the color recording apparatus having four recording heads has been described as an example, but black color or other single color recording can be similarly considered. INDUSTRIAL APPLICABILITY The present invention brings excellent effects particularly in a recording head and a recording apparatus of the inkjet recording system that forms flying droplets by utilizing thermal energy among the inkjet recording systems to perform recording.

Regarding its typical structure and principle, see, for example, US Pat. Nos. 4,723,129 and 4740.
No. 796, the present invention is preferably carried out using these basic principles. This recording method is applicable to both the so-called on-demand type and continuous type.

This recording method will be briefly described. A sheet (liquid) holding a liquid (ink) or an electrothermal converter arranged corresponding to a liquid path is changed to a liquid (ink) corresponding to recording information. Thermal energy is generated by applying at least one drive signal for giving a rapid temperature rise that causes the film boiling phenomenon beyond the nucleate boiling phenomenon, and causes the film boiling on the heat acting surface of the recording head. . In this way, bubbles can be formed in one-to-one correspondence with the drive signal applied from the liquid (ink) to the electrothermal converter, which is particularly effective for the on-demand recording method. By the growth and contraction of the bubbles, liquid (ink) is ejected through the ejection holes,
Form at least one drop. It is more preferable to make this drive signal into a pulse shape, because the bubble growth and contraction are immediately and appropriately performed, so that the ejection of the liquid (ink) with excellent responsiveness can be achieved. As the pulse-shaped drive signal, U.S. Pat. Nos. 4,463,359 and 4,345 are used.
Those as described in the '262 patent are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

The structure of the recording head is a combination of a discharge hole, a liquid flow path, and an electrothermal converter as disclosed in the above-mentioned specifications (straight liquid flow path or right-angled liquid flow path).
Besides, as disclosed in US Pat. No. 4,558,333 and US Pat. No. 4,459,600, the present invention also includes a structure in which the heat acting portion is arranged in the bending region.

In addition, Japanese Laid-Open Patent Publication No. 123670/1984, which discloses a structure in which a common slit is used as a discharge hole for a plurality of electrothermal converters, absorbs a pressure wave of thermal energy. The present invention is also effective in a structure based on Japanese Patent Laid-Open No. 138461/1984, which discloses a structure in which the corresponding opening corresponds to the discharge portion.

Further, as a recording head in which the present invention is effectively used, there is a full line type recording head having a length corresponding to the maximum width of the recording medium which can be recorded by the recording apparatus. The full line head may be a full line configuration formed by combining a plurality of print heads as disclosed in the above-mentioned specification, or may be a single full line print head integrally formed.

In addition, by being attached to the apparatus main body, it can be electrically connected to the apparatus main body and can be supplied with ink from the apparatus main body by a replaceable chip type recording head or the recording head itself. The present invention is also effective when a cartridge-type recording head that is specially provided is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc. to the recording apparatus of the present invention because the recording apparatus of the present invention can be made more stable. Specific examples thereof include cleaning means, pressurizing means, electrothermal converter or other heating element for the recording head, preheating means by a combination thereof, and recording means. It is also effective to perform stable recording by adding a means for performing the preliminary ejection mode for ejecting.

In the embodiment described above, excessive temperature rise of the head or ink due to thermal energy is positively prevented by using it as energy for changing the state of the ink from the solid state to the liquid state, or It is also possible to use an ink that solidifies when left standing for the purpose of preventing the evaporation of the ink. In any case, liquefaction occurs only when heat energy is applied, such as when the ink is liquefied by applying heat energy according to the recording signal and ejected as an ink liquid, or when it begins to solidify when it reaches the recording medium. The use of an ink having the property of applying is also applicable to the present invention. Such an ink is disclosed in JP-A-54-56.
As described in Japanese Patent No. 847 or Japanese Patent Application Laid-Open No. 60-71260, facing the electrothermal converter in a state of being held as a liquid or solid in the recesses or through holes of the porous sheet. It may be in the form.

In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0065]

As described above, the present invention has the following effects. (1) Since the idle discharge can be performed during the recording operation without moving the recording head, the throughput of the recording operation is improved, and the disturbance of the image due to the non-ejection of ink is eliminated, and the reliability is improved. (2) The ink adhering to the recording paper conveying means by the idle ejection is automatically removed by the ink removing means, so that the recording paper being recorded and the recorded image are not contaminated.
It is economically advantageous. (3) A space for moving the recording head for idle ejection,
Since it is not necessary to use an ink receiver or the like for receiving the ink that has been ejected in a blank state, the size of the device can be reduced. (4) By performing the idle discharge at a portion between the front end portion and the rear end portion of the recording paper which is being conveyed and where the recording paper does not exist, the idle discharge is regularly performed during the recording operation. Therefore, the reliability of the recording apparatus is further improved.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of an inkjet recording apparatus of the present invention.

FIG. 2 is a side view showing an example of a recording paper conveying unit and an ink removing unit.

3A and 3B are diagrams showing an example of a recording head mounted on a carriage, FIG. 3A is a side view and FIG. 3B is a rear view.

FIG. 4 is a flowchart showing an example of the operation of the inkjet recording apparatus of the present invention.

5A and 5B are views showing a second embodiment of the ink jet recording apparatus of the present invention, FIG. 5A is a plan view and FIG. 5B is a side view.

6A and 6B are views showing a third embodiment of the ink jet recording apparatus of the present invention, FIG. 6A is a plan view and FIG. 6B is a side view.

FIG. 7 is a perspective view showing a conventional drum transport type inkjet recording apparatus.

FIG. 8 is a perspective view showing a conventional plane-conveying inkjet recording apparatus.

9A and 9B are diagrams showing a conventional belt-conveying inkjet recording apparatus, in which FIG. 9A is a plan view and FIG. 9B is a side view.

[Explanation of symbols]

 101, 501, 601 Recording head 102 Carriage 103, 104 Guide 105 Motor pulley 106 Tension pulley 107 Wire 108 Rotating drum 109, 505, 605 Recording paper 110 Drum motor 111 Air tube 112 Cap 113 Opening 114 Carriage motor 115 Pump 116 Ink discharging Tube 117 Head support plate 118 Blade 119 Spindle 120 Waste ink receiver 121 Ink supply plate 122 Ink tank 123 Joint 124, 128 Heater 125 Ink supply pipe 126 Ink supply hole 127 Groove 401-417 Steps 502, 503, 602, 603 Pinch roller 504, 604 Recording paper transport head 506, 507, 606, 607 Roller 608 Web 609 Web supply Roller 610 web take-up roller 611 pressure roller 612 heater fan

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location B65H 5/00 B 7111-3F 8804-2C B41J 29/00 J

Claims (9)

[Claims] 1. A recording head for liquefying and discharging a solid ink having a melting point higher than room temperature, and the recording head.
An ejection control unit which outputs an ejection signal corresponding to an image at a predetermined timing, and a recording which conveys a single piece of recording paper in synchronization with the ejection signal at a predetermined conveyance interval in order to face the recording head. An ink jet recording apparatus including a paper transporting means, having an ink removing means for removing ink adhering to the recording paper transporting means, wherein the ejection control unit records during the recording operation of the recording paper transporting means. An inkjet recording apparatus, wherein a blank discharge signal for blank discharge other than an image recording purpose is applied to the recording head at a position where no paper is present. 2. The recording paper conveying means comprises a rotary drum for holding the recording paper by electrostatic attraction, and the ink removing means makes contact with a portion of the surface of the rotary drum where the recording paper does not exist over substantially the entire width. The inkjet recording apparatus according to claim 1, wherein the inkjet recording apparatus is a blade. 3. The ink jet recording apparatus according to claim 1, wherein the recording paper conveying means has a conveying belt that holds the recording paper by electrostatic attraction and conveys it in a plane. 4. The ink jet recording apparatus according to claim 3, wherein the ink removing means is a blade that is in contact with the conveying belt on the side opposite to the recording head over substantially the entire width of the surface of the conveying belt. 5. A web, in which the ink removing means is pressed against substantially the entire width of the surface of the carrying belt on the side opposite to the recording head of the carrying belt, and the upstream side in the moving direction of the carrying belt with respect to the web. 4. The ink jet recording apparatus according to claim 3, further comprising: a heating unit that is disposed at a position to heat the transport belt. 6. The ejection control unit outputs an idle ejection signal when a portion of the recording paper held by the recording paper conveying means between the front end portion and the rear end portion of the recording paper, which does not exist, faces the recording head. The inkjet recording apparatus according to claim 1, 2, 3, 4, or 5. 7. The ink jet recording apparatus according to claim 1, wherein the recording head is mounted on a carriage that is movable over the entire maximum recording width of the recording paper. .. 8. The inkjet according to claim 1, 2, 3, 4, 5 or 6, wherein the recording head is a full line type in which ink ejection openings are formed over the entire maximum recording width of the recording paper. Recording device. 9. The recording head is for ejecting ink by utilizing heat energy, and is provided with an electrothermal converter for generating the heat energy.
2. The ink jet recording apparatus according to 2, 3, 4, 5, 6, 7 or 8.