JP2001171138A - Ink-jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet recording apparatus in which ink of a cap is prevented from adhering to a recording medium, waving of the recording medium is sufficiently restricted and good images can be recorded even when the cap is inside a recording region to reduce a breadth of the recording apparatus. SOLUTION: The apparatus has a platen 8 for guiding a rear face of the recording medium P by a rib shape at a recording position opposite to a recording head 2, the cap 4 set within the recording region by notching part of the platen 8 for protecting a discharge opening of the recording head 2, and a shutter means 10 for shutting the recording head 2 and the cap 4. The shutter means 10 has the rib shape for guiding the rear face of the recording medium P, which opens when the recording head 2 is capped and closes when recording to the recording medium P is carried out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an ink jet recording apparatus which performs recording by discharging ink onto a recording medium.

[0002]

2. Description of the Related Art A recording device having a function such as a printer, a copying machine, a facsimile or the like, or a recording device used as an output device of a composite electronic device or a workstation including a computer or a word processor, etc. It is configured to record an image on a recording medium such as a thin plastic plate. This recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type, and the like according to a recording method.

In a serial type printing apparatus employing a serial scanning system in which a main scan is performed in a direction intersecting a conveying direction (sub-scanning direction) of a printing medium, an image is printed by a printing means mounted on a carriage moving along the printing medium. By repeating the operation of recording and performing a predetermined amount of paper feed (pitch conveyance) after completing the recording of one line, and then recording the image of the next line again on the stopped recording medium, Recording of the entire recording medium is performed. Among these recording apparatuses, an ink jet recording apparatus (ink jet recording apparatus) performs recording by discharging ink from a recording unit (recording head) onto a recording medium, and the recording unit can be easily made compact. High-definition images can be recorded at high speed, and can be recorded on plain paper without requiring special processing. Also, running cost is low,
The non-impact method has advantages such as low noise and easy recording of a color image using multicolor inks. Above all, a line-type apparatus using a line-type recording means in which multicolor discharge ports are arranged in the paper width direction can further increase the recording speed.

[0004] In particular, an ink jet type recording means (recording head) for discharging ink using thermal energy is an electrothermal transducer formed on a substrate through a semiconductor manufacturing process such as etching, vapor deposition, or sputtering. By forming an electrode, a liquid path wall, a top plate, and the like, it is possible to easily manufacture a device having a high-density liquid path arrangement (discharge port arrangement) and achieve further downsizing.

[0005] In the above-described ink jet recording head, if the ink is not ejected for a long period of time, the ink in the nozzles evaporates and dries, causing the ink to thicken and solidify, resulting in ejection failure. In order to prevent this, at the time of non-printing, the ink in the nozzles is prevented from thickening and solidifying by closing the discharge port surface of the print head with a cap made of an elastic member such as rubber.

[0006] Generally, the cap is provided outside the recording area so as to avoid contact with the recording medium because the ink is attached thereto. However, as shown in FIG. 10, there is a case where the cap 4 is provided by cutting out a part of the platen 8 through which the recording medium passes for the purpose of reducing the width of the recording apparatus. At this time, when the recording head 2 is capped, the cap 4 is raised to come into contact with the recording head 2, and when recording on the recording medium, it is retracted below the paper passing surface so as not to contact the recording medium. .

[0007]

However, the conventional ink jet recording apparatus has the following problems. At the time of recording on a recording medium, the cap is retracted below the paper passing surface so as not to contact the recording medium. However, the distance retracted downward is insufficient, and there is a possibility that the ink comes into contact with the recording medium. In addition, even if the ink does not directly contact, the ink attached to the cap may adhere to the platen and contact the recording medium.

[0008] Further, if high-duty printing is performed on a recording medium with little stiffness, the recording medium will be wavy. When the recording medium is wavy, the recorded image is disturbed because the recording medium comes into contact with the recording head or the distance between the recording medium and the recording head varies greatly depending on the location. Therefore, in order to suppress the waving, a platen may be provided with a rib shape. However, in the conventional recording apparatus, since a part of the platen is cut off,
Since the rib shape cannot be provided in that portion, the waving of the recording medium cannot be sufficiently suppressed, and the image is disturbed.

The present invention has been made in view of the above circumstances,
Even if the cap is in the recording area in order to reduce the width of the recording apparatus, the ink of the cap does not adhere to the recording medium, the ripple of the recording medium is sufficiently suppressed, and the ink jet recording can record a good image. It is intended to provide a device.

[0010]

To achieve the above object, one aspect of the ink jet recording apparatus according to the present invention is:
In an ink jet recording apparatus for performing recording by discharging ink on a recording medium arranged opposite to a recording unit, a platen for guiding a back surface of the recording medium by a rib shape at a recording position facing the recording unit, A cap that protects the ejection port of the recording unit, and a shutter unit that shuts off the recording unit and the cap, wherein the shutter unit is provided in the recording area by cutting out a part of the shutter unit. It has a rib shape for guiding the back surface of the recording medium, and is opened when the recording means is capped and closed when recording on the recording medium.

Further, the shutter means is retracted below the platen when opened.

Further, the notch of the platen is sufficiently larger than the cap.

[0013] Further, the shutter means is provided with a cleaner means for wiping ink.

Further, the recording means records the image using ink droplets formed by thermal energy.

According to the above arrangement, the platen for guiding the back surface of the recording medium in the form of a rib at the recording position facing the recording means, and the recording means provided in the recording area with a portion of the platen cut away. It has a cap for protecting the discharge port, a shutter means for shutting off the recording means and the cap, and the shutter means has a rib shape for guiding the back surface of the recording medium, and is opened when the recording means is capped. ,
Since the cap is closed at the time of recording on the recording medium, the ink of the cap does not adhere to the recording medium, the waving of the recording medium is sufficiently suppressed, and a good image can be recorded.

When the shutter means is opened,
Since the recording unit is retracted below the platen, there is no problem in capping the recording unit.

Further, since the notch of the platen is sufficiently larger than the cap, the ink of the cap does not adhere to the platen.

Further, since the shutter means is provided with the cleaner means for wiping the ink, the ink adhered to the edge of the platen by opening and closing the shutter means can be wiped off.

Further, since the recording means records an image using ink droplets formed by thermal energy, the recording of the image can be executed quickly and accurately.

[0020]

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

<First Embodiment> FIG. 1 is a plan view of an ink jet recording apparatus according to a first embodiment of the present invention. FIG. 2 is a front view of the inkjet recording apparatus during recording. FIG. 3 is a front view of the ink jet recording apparatus at the time of capping.

Reference numeral 2 denotes a recording head which records an image on the recording medium P by discharging ink from the ink discharge port 2a. The recording head 2 is mounted on the carriage 1 and reciprocates while being supported by a guide shaft 3 that guides the moving direction. 11
Is a timing belt fixed to the carriage 1. Reference numeral 12 denotes a carriage motor, and a timing belt 11
, The carriage 1 is driven.

Reference numeral 4 denotes a cap for closing the ink discharge port 2a of the recording head 2 during non-printing and suction. 5
Is a cap lever for holding the cap 4. The cap 4 moves up and down as the cap lever 5 rotates about the rotation center 5a. In this embodiment, the cap 4 is moved up and down by rotation of the cap lever 5, but may be moved up and down by a cam or the like. A suction pump 7 sucks ink from the recording head 2 via a suction tube 6.

Numeral 8 is a platen having a plurality of ribs 8a.
The back of the recording medium P is guided. The platen 8 is partially cut out in the recording area, and the cap 4 that moves up and down is provided in the cutout. Since the notch of the platen 8 is sufficiently large with respect to the cap 4,
When the ink moves up and down, the ink attached to the cap 4 does not adhere to the platen 8. 10 is a recording head 2
Shutter means for shutting off the cap 4 and the recording medium P
Has a rib portion 10b for guiding the rear surface of the substrate. Rib part 10b
Have substantially the same shape and substantially the same height as the ribs 8a of the platen 8. When recording on the recording medium P, the shutter means 10
Covers the notch of the platen 8, and the rib portion 10b guides the back surface of the recording medium P in cooperation with the rib 8a of the platen 8.

FIG. 4 shows a front view of the shutter means 10. The shutter means 10 includes a base 10a, a rib 1
0b, guide portion 10c (shown in FIG. 5), compression spring 10d
It is composed of The shutter means 10 is fixed to a rotating shaft 8b provided on the platen 8, and is configured to be rotatable around the rotating shaft 8b by a drive source (not shown) such as a motor. The height of the shutter means 10 is supported by the guide portion 8c of the platen 8 and the stopper 13 in the vertical direction.

FIG. 5 is a side view showing the shutter means 10 closed during recording, as viewed from the left. FIG. 6 is a side view of the shutter means 10 opened at the time of capping as viewed from the left side.

In FIG. 5, the rib 10b of the shutter means 10 is guided by the guide 10c,
It is urged upward by d. When the shutter means 10 is rotated by a drive source (not shown) to open the notch of the platen 8, the slope of the rib 10 b hits the platen 8. Then, the rib portion 10b is lowered against the spring force of the compression spring 10d, and is housed below the platen 8 (the state of FIG. 6). Thereby, the notch of the platen 8 is opened, and the cap 4 comes out of the face.

FIG. 7 is a flowchart showing the operation of the first embodiment of the present invention. At the time of non-recording, as shown in FIGS. 3 and 6, the shutter means 10 (not shown in FIG. 3) is accommodated below the platen 8, and the notch of the platen 8 is open. The recording head 2 is in contact with the cap 4 and is capped.

When a recording command is issued, the cap 4 is lowered,
The contact with the recording head 2 is released. Next, the shutter means 10 is rotated by a drive source (not shown) to close the notch of the platen 8 (the state shown in FIGS. 2 and 5).

At the time of recording on the recording medium P, the shutter means 1
The zero rib portion 10b has substantially the same shape as the rib 8a of the platen 8, and has substantially the same height. Therefore, even when high-duty recording is performed on the recording medium P, the waving of the recording medium P is sufficiently suppressed, and a good image can be recorded.

When the recording operation is completed, the carriage 1 is driven so that the recording head 2 comes to the capping position. Next, the shutter means 10 is rotated by a drive source (not shown), and a cutout portion of the platen 8 is opened. In this state, the cap 4 rises and comes into contact with the recording head 2 to perform capping (the state shown in FIG. 3).

According to the configuration described above, the shutter means 10 has the rib portion 10b for guiding the back surface of the recording medium P, and is opened when the recording head 2 is capped, and is opened when recording on the recording medium P. Since the ink is closed, the ink of the cap 4 does not adhere to the recording medium P, and the waving of the recording medium P is sufficiently suppressed, and a good image can be recorded.

<Second Embodiment> FIGS. 8 and 9 show a second embodiment of the present invention. FIG. 8 is a front view showing a state in which the shutter means 20 is closed during recording, and FIG. 9 is a front view showing a state in which the shutter means 20 is opened during capping.

In the first embodiment, the shutter means 10 is opened and closed by rotation. However, as shown in FIGS. 8 and 9, the shutter means 10 may be linearly moved and opened and closed.

Reference numeral 20 denotes shutter means for shutting off the recording head 2 and the cap 4, and has a rib portion 20b for guiding the back surface of the recording medium P. Rib portion 20 of shutter means 20
b is rotatably provided on a support portion 20f provided on the base portion 20a by a torsion coil spring (not shown). When the shutter means 20 is closed at the time of recording on the recording medium, the rib portion 20b is supported substantially vertically, and guides the back surface of the recording medium P.

The shutter means 20 has a rack 20g for opening and closing. Reference numeral 21 denotes a drive gear that meshes with the rack 20g. When the drive gear 21 rotates in the direction A in the figure by a driving source (not shown), the drive gear 21 meshes with the rack portion 20g of the shutter means 20, and the shutter means 20 moves in the direction B in the figure. Rib portion 20b of shutter means 20
Corresponds to the platen 8. Then, the rib portion 20b falls down in opposition to the spring force of the torsion coil spring, and the shutter means 2
0 is stored under the platen 8 (the state of FIG. 9).

At the right end in the drawing of the shutter means 20, a cleaner means 20e for wiping ink is provided.
In FIG. 9, the shutter means 20 comes into contact with the platen 8 in a state of being housed under the platen 8. Thus, when the rib portion 20b of the shutter means 20 hits the platen 8, the ink attached to the end of the platen 8 can be wiped off so that the ink at that portion is not transferred.

According to the structure described above, the shutter means 20 is moved linearly by the rack, so that the mechanism for opening and closing the shutter means 20 is simplified.
In addition, a housing portion provided on the platen 8 for housing the shutter means 20 can be small.

<Others> It should be noted that the present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for performing ink ejection, particularly in an ink jet recording system. An excellent effect is obtained in a recording head and a recording apparatus of a type in which the state of ink is changed by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any of the continuous type, particularly, in the case of the on-demand type, the electric heat disposed corresponding to the sheet or the liquid path holding the liquid (ink or processing liquid) is used. By applying to the transducer at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding the nucleate boiling, the electrothermal transducer generates heat energy and is applied to the heat acting surface of the recording head. This is effective because film boiling can be caused, and as a result, bubbles in the liquid (ink or processing liquid) corresponding to this drive signal one-to-one can be formed. A liquid (ink or processing liquid) is ejected through an ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubbles are immediately and appropriately performed, and therefore, the ejection of a liquid (ink or processing liquid) having particularly excellent responsiveness is more preferable. Examples of the drive signal in the form of a pulse include those described in U.S. Pat.
Suitable are those described in US Pat. No. 45,262. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned specifications, U.S. Pat. Nos. 4,558,333 and 44,596 which disclose a configuration in which a heat acting portion is arranged in a bending region.
The configuration using the specification of No. 00 is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. Sho 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure liquid of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

In addition, even in the case of the serial type as described above, the recording head fixed to the apparatus main body or the electric connection with the apparatus main body or the ink from the apparatus main body is attached to the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

Further, it is preferable to add a discharge recovery means for the recording head, a preliminary auxiliary means, and the like as the constitution of the recording apparatus of the present invention since the effect of the present invention can be further stabilized. To be specific, these are pre-heating by using a capping unit, a cleaning unit, a pressurizing or suctioning unit, an electrothermal transducer or another heating element or a combination thereof for the recording head. Means and preliminary ejection means for performing ejection other than recording.

Regarding the type or number of print heads to be mounted, for example, in addition to one provided for a single color ink, a plurality of inks having different print colors and densities are provided. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the full-color recording modes using mixed colors.

In addition, in the embodiment of the present invention described above, the ink is described as a liquid.
An ink that solidifies at room temperature or below and softens or liquefies at room temperature may be used, or the ink jet method controls the viscosity of the ink by adjusting the temperature of the ink itself within the range of 30 ° C to 70 ° C. Is generally controlled so as to be within the stable ejection range, so that the ink may be in a liquid state when the use recording signal is applied. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start to solidify when reaching the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink is disclosed in JP-A-54-56847 or JP-A-60
As described in JP-A-71260, a configuration may be adopted in which a liquid or solid substance is held in a concave portion or through hole of a porous sheet and opposed to an electrothermal converter. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the form of the ink jet recording apparatus of the present invention is not limited to those used as image output terminals of information processing equipment such as computers, copying apparatuses combined with readers and the like, and facsimile apparatuses having a transmission / reception function. It may take a form.

[0047]

As is apparent from the above description, in the ink jet recording apparatus according to the first aspect of the present invention, the rear surface of the recording medium has a rib shape at the recording position facing the recording means. A shutter provided with a platen for guiding, a cap provided in the printing area by cutting out a part of the platen, for protecting a discharge port of the printing means, and a shutter means for shutting off the printing means and the cap; Has a rib shape for guiding the back surface of the recording medium,
Since the recording means is opened during capping and closed during recording on the recording medium, the ink of the cap does not adhere to the recording medium, the wave of the recording medium is sufficiently suppressed, and a good image can be recorded.

In the ink jet recording apparatus according to the second aspect of the present invention, when the shutter means is opened, it is retracted below the platen, so that there is no problem in capping the recording means.

In the ink jet recording apparatus according to the third aspect of the present invention, since the notch of the platen is sufficiently larger than the cap, the ink of the cap does not adhere to the platen.

In the ink jet recording apparatus according to the fourth aspect of the present invention, since the shutter means is provided with the cleaner means for wiping the ink, the ink adhered to the platen can be wiped by opening and closing the shutter means.

In the ink jet recording apparatus according to the fifth aspect of the present invention, since the recording means records an image using ink droplets formed by thermal energy, the image recording can be performed quickly and accurately.

[Brief description of the drawings]

FIG. 1 is a plan view of an ink jet recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a front view of the inkjet recording apparatus at the time of recording according to the first embodiment of the present invention.

FIG. 3 is a front view of the inkjet recording apparatus at the time of capping according to the first embodiment of the present invention.

FIG. 4 is a front view of the shutter means according to the first embodiment of the present invention.

FIG. 5 is a side view of the shutter unit during recording according to the first embodiment of the present invention.

FIG. 6 is a side view of the shutter means at the time of capping according to the first embodiment of the present invention.

FIG. 7 is a flowchart of an operation according to the first exemplary embodiment of the present invention.

FIG. 8 is a front view of an ink jet recording apparatus during recording according to a second embodiment of the present invention.

FIG. 9 is a front view of the inkjet recording apparatus at the time of capping according to the second embodiment of the present invention.

FIG. 10 is a plan view of a conventional inkjet recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Carriage 2 Recording head 3 Guide shaft 4 Cap 5 Cap lever 6 Suction tube 7 Suction pump 8 Platen 10 Shutter means 11 Timing belt 12 Carriage motor 13 Stopper 20 Shutter means 21 Drive gear

Claims (5)

[Claims] 1. An ink jet recording apparatus which performs recording by discharging ink on a recording medium arranged opposite to a recording means, wherein a back surface of the recording medium is guided by a rib shape at a recording position opposed to the recording means. A platen, a cap provided in the recording area by cutting out a part of the platen, and a cap for protecting the ejection port of the recording unit; and a shutter unit for shutting off the recording unit and the cap. The ink jet recording apparatus according to claim 1, wherein the shutter has a rib shape for guiding a back surface of the recording medium, and is opened when the recording means is capped and closed when recording on the recording medium. 2. When the shutter means is opened,
The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus is retracted below the platen. 3. The notch of the platen is sufficiently larger than the cap.
3. The ink jet recording apparatus according to claim 1. 4. An ink jet recording apparatus according to claim 1, wherein said shutter means is provided with a cleaner means for wiping ink. 5. An ink jet recording apparatus according to claim 1, wherein said recording means records said image by ink droplets formed by thermal energy.