JP2001191557A - Ink-jet type recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that ink drops discharged by a flushing operation float as mist and contaminate surroundings. SOLUTION: A case-like ink collection unit 31 is set to a move path of a recording head 22 loaded to a carriage 21. A reception opening part 32 where ink drops discharged from the recording head by the flushing operation is formed to the collection unit. A chain of air passages 41 is formed to turn up and down inside the unit, with an exhaust fan 42 disposed to a terminal end part of the air passage. Even if the ink drops discharged from the recording head change into ink mist, the ink mist can be surely taken into the unit by an air flow and trapped at the chain of air passages formed to turn up and down.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention includes an ink jet recording head for forming an image on a recording sheet by discharging ink droplets from nozzle openings, and ink droplets discharged when a flushing drive signal is supplied to the recording head. In particular, the present invention relates to an ink-jet recording apparatus in which a flushing area receiving light is arranged on a moving path of a recording head, and particularly to an ink-jet recording apparatus capable of effectively collecting unnecessary mist (fog-like ink) due to minute ink droplets generated during a flushing operation. The present invention relates to an expression recording device.

[0002]

2. Description of the Related Art Ink jet recording apparatuses have been used in many types of printing including color printing in recent years, since noise at the time of printing is relatively small and small dots can be formed at a high density. Such an ink jet recording apparatus is generally mounted on a carriage and scans in the width direction of recording paper, and an ink jet recording head;
A paper feeder is provided for moving the recording paper in a direction perpendicular to the scanning direction of the recording head, and recording is performed by discharging ink droplets from the recording head onto the recording paper in accordance with print data.

[0003] By constructing such that black ink and each color ink of yellow, cyan and magenta can be continuously supplied to the recording head,
Not only text printing with black ink but also full-color printing is possible by changing the discharge ratio of each color ink.

In such an ink jet type recording head, the ink pressurized in the pressure generating chamber is ejected from the nozzle opening as ink droplets onto the recording paper to perform printing. There is a problem that printing failure occurs due to an increase in ink viscosity, solidification of the ink, adhesion of dust, and mixing of air bubbles. For this purpose, the ink jet recording apparatus is provided with a capping means for sealing the nozzle openings of the recording head during non-printing and a wiping member for wiping and cleaning the nozzle forming surface as required.

[0005] The capping means not only functions as a lid for preventing the ink from drying in the nozzle openings of the recording head when printing is stopped, but also when the nozzle openings are clogged, the capping means is provided with a suction pump. It also has a function of sucking and discharging ink from the nozzle opening in response to a negative pressure to eliminate clogging due to solidification of the ink in the nozzle opening and ink ejection failure due to air bubbles entering the ink flow path.

[0006] Forcible suction and discharge of ink for eliminating the clogging of the recording head and the incorporation of air bubbles into the ink flow path is called a cleaning operation. If you want to resume printing later,
This is executed, for example, when the user recognizes that the quality of the print image has deteriorated and operates, for example, a cleaning switch. After the ink is sucked and discharged from the recording head, an operation of wiping the nozzle forming surface of the recording head with a wiping member made of an elastic plate such as rubber is involved.

The recording head also has a function of applying a drive signal unrelated to printing to eject ink droplets. This function is called a flushing operation, and the nozzle of the head is wiped by the wiping member. This operation is performed at regular intervals in order to recover irregular meniscuses generated in the vicinity of the opening, and to prevent clogging due to thickening of ink in the nozzle opening where ink droplets are not discharged during printing.

FIG. 5 shows an example of a conventional ink jet recording apparatus configured to discharge an ink droplet toward a flushing area formed on a moving path of a recording head during a flushing operation.

In FIG. 5, reference numeral 1 denotes a carriage,
The carriage 1 is driven via a timing belt driven by a carriage motor (not shown) to drive the left and right frames 2 and 2.
It is configured to be guided by a guide shaft 4 supported by 3 and reciprocated in the axial direction.

An ink jet recording head 5 is mounted on the carriage 1 downward, and a black ink cartridge 6 for supplying ink to the recording head 5 and a color ink cartridge 7 are detachably mounted on an upper portion thereof. Mounted as possible. A paper guide member 8 is arranged below the recording head 5 corresponding to the scanning direction, and the recording paper 9 placed on the paper guide member 8 is recorded by a paper feeding means (not shown). The head 5 is configured to be sequentially transported in a direction orthogonal to the scanning direction.

In the drawing, reference numeral 10 denotes capping means disposed in a non-printing area (home position). When the recording head 5 moves directly upward, it moves upward to seal the nozzle forming surface of the recording head 5. It is configured to be able to stop. Below the capping means 10, a suction pump 11 for applying a negative pressure to the internal space of the capping means 10 is arranged.

As described above, the capping means 10 functions as a lid for preventing the nozzle openings of the recording head 5 from drying during the pause of the recording apparatus, and also applies a negative pressure from the suction pump 11 to the recording head 5. It also has a function as a cleaning means for causing the ink to be sucked and discharged by acting.

In the vicinity of the capping means 10, a wiping member 12 formed of an elastic plate or the like such as rubber is arranged. When the carriage 1 reciprocates toward the capping means 10, the recording head 5 is moved. The wiping operation for wiping the nozzle forming surface is performed.

On the other hand, a flushing area 13 is formed in the vicinity of the other end facing the capping means 10 via the central printing area. The flushing area 13 is formed by an opening formed so as to penetrate the paper guide member 8. A part of a waste liquid absorber 14 that absorbs and retains ink discharged from the capping unit 10 via the pump 11 is disposed at the inner bottom of the opening that forms the flushing region 13.
The absorbent 14 is accommodated in an absorbent storage case disposed along the paper guide member 8, that is, in a waste liquid tank 15.

[0015]

As described above, in such a recording apparatus, flushing is periodically performed in order to prevent a discharge failure due to ink thickening at an unused nozzle during printing. It is configured to: In particular, in recent models, flushing of about several tens of shots / one nozzle is performed on average every few seconds. In this flushing operation, thousands to tens of thousands of shots may be ejected from each nozzle at a timing after the cleaning operation to prevent color mixing, at a timing at the start of printing, and periodically during printing. is there.

When an opening hole is formed in the paper guide member 8 as the flushing area 13 as shown in FIG. 5, the distance from the nozzle forming surface of the recording head 5 to the waste liquid absorbing material 14 is about several tens mm. Inevitably, the flying distance of the ink is increased. For this reason, some of the ink droplets ejected from the nozzle openings of the recording head become mist (fog ink) due to air resistance before reaching the absorbing material 14 and float as indicated by the arrow, and the recording paper And the problem of contaminating the inside and outside of the apparatus.

In order to prevent such a problem from occurring, it is conceivable to arrange a waste liquid absorbing material at a position close to the recording head. In fact, it is not possible to secure a sufficient volume.

In addition, the ink droplets ejected from the nozzle openings are charged to a considerable extent, and are affected by the static electricity generated in the drive unit in the recording apparatus, and the air is exhausted by an exhaust fan arranged to suppress the temperature rise in the apparatus. The flow is accelerated by the flow or the air flow accompanying the movement of the carriage, and as described above, there remains a problem that the recording paper and the inside and outside of the recording apparatus are contaminated. In particular, in a recent printing apparatus in which the amount of each ink droplet is controlled as small as possible in order to realize high image quality, such a problem appears more remarkably.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and provides an ink jet recording apparatus capable of effectively collecting ink mist floating as fine droplets, particularly during a flushing operation. Accordingly, it is an object of the present invention to provide an ink jet recording apparatus having a high commercial value without contaminating the inside and outside of the apparatus.

[0020]

In order to achieve the above-mentioned object, an ink jet recording apparatus according to the present invention is mounted on a carriage which scans a recording sheet in a width direction and ejects ink droplets from nozzle openings. An ink jet recording apparatus comprising: an ink jet recording head for forming an image on recording paper by performing recording; and an ink recovery unit that receives ink droplets when a flushing drive signal is supplied to the recording head and is disposed on a moving path of the recording head. The ink recovery unit includes a unit box formed in a housing shape and an exhaust fan, and the unit box allows ink droplets ejected from a nozzle opening of a recording head to pass through by a flushing operation. The receiving opening is formed, and the direction of gravity and the A series of air passages is formed so as to be turned up and down in the anti-gravity direction, and the exhaust fan is disposed in the air passage of the unit box or at the end of the air passage, and a receiving opening of the unit box is provided. From the air flow path toward the end of the air flow path.

In this case, immediately after the receiving opening in the unit box, an ink droplet collecting space is formed in the direction of gravity, and the air flow path in the anti-gravity direction is formed immediately after the receiving opening. It is desirable that they are formed toward the surface. Further, preferably, in the ink droplet collection space formed immediately after the receiving opening,
A waste liquid outlet is formed at the lower bottom.

On the other hand, preferably, a plate-like body for further increasing the surface area of the air flow path is arranged in the air flow path.
In this case, it is preferable that the plate-shaped members are arranged so as to be alternated in the air flow path, and the plate-shaped members are formed so as to meander in the air flow path further in the horizontal direction.

In a preferred embodiment,
Each of the plate-like bodies arranged so as to be alternated in the air flow path is formed in a state where the tip end of each plate-like body is inclined in the direction of gravity. Further, the respective plate-like bodies formed so as to be staggered are arranged in the air flow path in the antigravity direction.

Further, it is preferable that a waste liquid guiding hole communicating with the ink droplet collecting space is formed in a lower bottom portion of a series of air flow paths formed so as to be folded up and down. Preferably, an air filter is arranged in a part of the air flow path. In this case, the air filter is preferably arranged immediately before the exhaust fan.

In a preferred embodiment,
In the unit box, one side wall, a peripheral side wall connected to the side wall, and an inner wall body forming a series of air passages are integrally formed inside the peripheral side wall, and the other side surface facing the one side wall is open. And a sealing member that seals the open end of the box-shaped member to form a housing.

In this case, preferably, the sealing member is made of a heat-sealing film, and the heat-sealing film seals the open end of the box-shaped member.

According to the ink jet recording apparatus constructed as described above, the ink droplets ejected from the nozzle openings of the recording head located in the flushing area are immediately discharged from the ink receiving unit formed in the ink recovery unit. It is introduced into the collection unit.

The ink droplets ejected from the nozzle openings of the recording head are collected in an ink droplet collecting space formed in the unit box immediately after the receiving opening toward the direction of gravity. The waste liquid collected in the ink droplet collecting space can be discharged to the outside through a waste liquid outlet formed in the lower bottom portion of the ink droplet collecting space.

On the other hand, even if a part of the ink droplet changes to a mist while being ejected to the receiving opening in the unit box and flying, the mist is transferred to the air flow path in the unit box or to the terminal end thereof. The airflow from the arranged exhaust fan ensures that the air is taken into the unit box.

Then, the ink mist taken into the unit box rides on the airflow from the exhaust fan,
The air passes through a series of air flow paths formed so as to turn up and down in the direction of gravity and the direction of anti-gravity, and is captured while contacting the wall surface of the air flow path.

In this case, the contact area of the ink mist can be substantially increased by arranging the plate-like body in the air flow path, so that the efficiency of ink mist recovery can be improved.

Further, by arranging the plate-like bodies so as to be alternated in the air flow path, the air flow path is formed so as to meander in the horizontal direction by each plate-like body. Accordingly, the moving path of the air flow becomes more complicated, and the efficiency of collecting the ink mist can be further improved.

[0033]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an ink jet recording apparatus according to the present invention will be described based on an embodiment shown in the drawings. FIGS. 1 to 4 all show an ink recovery unit provided in the ink jet recording apparatus according to the present invention. FIG. 1 is a perspective view showing the entire unit box constituting the ink recovery unit.

FIG. 2 shows a state in which the ink recovery unit is viewed from the front, and FIG. 3 is a sectional view of the unit box cut along a vertical plane. FIG. 4
(A) and (B) are side views of the ink collection unit viewed from the left and right directions, respectively.

This ink recovery unit is employed in a recording apparatus in which the nozzle forming surface of an ink jet recording head 22 mounted on a carriage 21 is arranged obliquely downward as shown in FIG. 2, for example. You. That is, in FIG. 2, the carriage 21 and the recording head 22 mounted on the carriage 21 are configured to reciprocate in a direction perpendicular to the paper surface, whereby the recording head 22 is fed in an oblique direction (not shown). It is configured to be able to scan in the width direction of the recording paper.

The ink collecting unit is disposed on a part of the moving path of the recording head 22, and functions to collect ink droplets that are ejected from the recording head 22 based on the flushing operation.

As shown in FIGS. 2 and 3, the unit box 31 constituting the ink recovery unit has a receiving opening through which ink droplets ejected from the nozzle openings of the recording head 22 by the flushing operation can pass. 32 are formed. In this embodiment, between the receiving opening 32 formed in the unit box 31 and the scanning area of the carriage 21, another component member 25 not related to the ink recovery unit is provided. It is arranged in a state attached to 31.

The ink droplets based on the flushing operation are directed toward the receiving opening 32 formed in the unit box 31 through the duct-like opening 25a (see FIG. 3) formed in the component member 25. It is made to be ejected.

Immediately after the receiving opening 32 in the unit box 31, an ink droplet collecting space 33 is formed in the direction of gravity, that is, downward. Therefore, most of the ink droplets ejected from the recording head 22 based on the flushing operation fall into the ink droplet collecting space 33 formed in the direction of gravity, and are temporarily stored in the lower bottom portion 34 thereof. You. The lower bottom portion 34 of the ink droplet collecting space 33 is formed with an inclined surface which decreases toward a substantially central portion thereof, and a waste liquid outlet is provided at the lowest position formed by the two inclined surfaces. 35 are formed.

Therefore, most of the ink droplets ejected based on the flushing operation are stored in the ink droplet collecting space 3.
3, go down the inclined surface formed in the lower bottom part 34, and
And can be discharged through a waste pipe 36 formed so as to protrude from the discharge port 35 to the outside.

On the other hand, an air flow path 41 is formed immediately after the receiving opening 32 in the unit box 31 so as to be directed in the antigravity direction, that is, upward. As shown in FIGS. 1 to 3, the air passage 41 is formed in a meandering manner so as to be folded up and down, and an upper end of a unit box constituting a terminal end of the air passage 41 is provided at the upper end. , An exhaust fan 42 is arranged as shown in FIG.

In this configuration, when the exhaust fan 42 is driven, an airflow is formed from the receiving opening 32 of the unit box through the air passage 41 toward the terminal end of the air passage, that is, toward the exhaust fan 42. .
In this case, the flow rate of the air in the receiving opening 32, that is, the suction flow rate, is preferably adjusted to be about 1 m / sec or more.

According to this configuration, when a part of the ink droplet ejected from the recording head by the flushing operation changes into an ink mist during the flight, the ink mist is meandering up and down along with the air flow. Air flow path 41
Guided in.

In this embodiment, in the series of air passages 41, the air passage in the anti-gravity direction (upward) has a large width, and the wide air passage has The plate-like members 43 are formed so as to be alternated.

Each of the plate members 43 functions to substantially increase the surface area of the air flow path. Further, as described above, each of the plate members 43 is arranged so as to be staggered, so that each of the plate members 43 is staggered. The air flow path 41 is formed so as to meander in the horizontal direction by the plate-like body.

Therefore, the ink mist riding on the air flow meanders up and down, and passes through the air flow passage 41 meandering left and right by each plate-like body, thereby forming the air flow passage 4.
1 and contact with the wall surface or each of the plate-like bodies 43.

Then, as shown in FIGS. 1 to 3,
Each of the plate-like members 43 is formed such that the tip end of each plate-like member is slightly inclined in the direction of gravity. With this configuration, the waste liquid due to the ink mist captured by each plate-like body flows down the surface of each plate-like body 43 and falls downward, and therefore, the collection of the waste liquid is promoted.

In this embodiment, as shown in FIGS. 1 and 2, in the air flow path from the receiving opening 32 to the terminal end, the air flow path in which A waste liquid guiding hole 45 communicating with the ink droplet collecting space 33 described above is formed in the lower bottom portion 44 in FIG.

The lower bottom part 44 in the air flow path described above
The waste liquid guide hole 4 is formed at the lowest position formed by the inclined surface which decreases in one direction.
5 are formed.

Therefore, the waste liquid which is caught in contact with each plate-like body 43 and dropped on the lower bottom portion 44 in the air flow path goes down the inclined surface formed in the lower bottom portion 44 and passes through the waste liquid guide hole 45. The ink is introduced into the ink droplet collecting space 33. The waste liquid thus introduced into the ink droplet collecting space 33 is guided to the outlet 35 as described above, and
Is discharged through the waste pipe 36.

In this embodiment, the waste liquid guide hole 45 as described above is provided at the lower bottom of the air flow passage where the plate-like body 43 is disposed at a position near the end of the air flow passage.
Is not formed. This is because the concentration of the ink mist is extremely low because it is close to the end of the air flow path, and no waste liquid is accumulated in the portion. However, depending on the design of the air flow path and the like, waste liquid may accumulate even at a position near the end of the air flow path. In this case, the waste liquid guide hole 45 is similarly formed at the lower bottom.
Is desirably formed so that the waste liquid can be discharged.

On the other hand, immediately before the exhaust fan 42 disposed at the end of the air flow path, an air filter 51 is disposed as shown in FIG. The air filter 51 is formed in a rectangular shape and in a flat shape, and is fitted into a space formed by a rib 52 along the outer shape. Therefore, minute ink mist that is not captured by the above-described series of air flow paths can be captured by the air filter 51.

As can be understood from the overall structure shown in FIG. 1, the unit box 31 constituting the ink recovery unit has a single side wall 31a and a peripheral side wall 31b connected thereto, which are integrally formed. Constitutes a box-shaped member whose other side face is open. Further, an inner wall 31c that forms the series of air flow paths and the like is integrally formed inside the inside surrounded by the peripheral side wall based on the one side wall 31a.

With this configuration, the one side wall 31a, the peripheral side wall 31b, and the inner wall body 31c can be integrally formed by, for example, injection molding. Then, the housing-shaped unit box 31 can be formed by sealing the open end of the integrally formed box-shaped member with a plate-shaped sealing member.

In this embodiment, as the sealing member, a heat welding film 55 made of a transparent resin material is used as shown in FIG. That is, the heat welding film 55 is cut in advance so as to substantially conform to the outer shape of the peripheral side wall 31b integrally formed with the one side wall 31a.

After the thermal welding film 55 is placed along the open end of the peripheral side wall 31b, a heater chip (not shown) is brought into contact with the heater chip from above, so that the thermal welding film 55 is A unit box 31 welded to each open end of the inner wall 31b and the inner wall 31c and formed in a housing shape can be obtained.

In place of the heat-sealing film 55,
It is also possible to use a flat sealing member. In this case, for example, a flat sealing member is formed of a thermoplastic synthetic resin, and the sealing member is welded to each open end of the peripheral side wall 31b and the inner wall body 31c by using a means such as vibration welding. Can be done.

In the embodiment described above, the exhaust fan is disposed at the end of the air flow path formed in the unit box. However, this is disposed in the air flow path formed in the unit box. However, the same operation and effect can be obtained. Further, in the embodiment, the air filter is disposed immediately before the exhaust fan,
Even if this air filter is arranged at any place in the air flow path formed in the unit box, the same effect can be obtained.

[0059]

As is apparent from the above description, according to the ink jet recording apparatus of the present invention, the ink box ejected from the nozzle opening of the recording head by the flushing operation is placed in the unit box constituting the ink recovery unit. A receiving opening that can pass through is formed,
A series of air passages is formed inside the inside so as to be turned up and down in the direction of gravity and the direction of antigravity. Then, an air flow is formed by the exhaust fan from the receiving opening toward the end of the air flow path, so that even if the ink droplet ejected from the nozzle opening changes to an ink mist, the air flow forms the inside of the unit box. Can be reliably captured. And since the ink mist is captured in a series of air flow paths formed so as to turn up and down,
The problem that the inside and outside of the apparatus are contaminated by the ink mist can be solved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an overall configuration of a unit box in an ink recovery unit provided in an ink jet recording apparatus according to the present invention.

FIG. 2 is a front view of an ink recovery unit in which an exhaust fan is mounted on the unit box shown in FIG.

FIG. 3 is a vertical sectional view of the unit box shown in FIG. 1 cut along a vertical plane.

FIG. 4 is a side view of the ink collection unit viewed from left and right directions.

FIG. 5 is a longitudinal sectional view showing an example of forming a flushing area in a conventional ink jet recording apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Carriage 22 Recording head 25a Duct opening 31 Unit box 31a One side wall 31b Perimeter side wall 31c Inner wall body 32 Receiving opening part 33 Ink droplet collection space part 34 Lower bottom part 35 Waste liquid discharge port 36 Waste pipe 41 Air flow path 42 Exhaust fan 43 Plate Form 44 Lower bottom part 45 Waste liquid guide hole 51 Air filter 52 Rib 55 Thermal welding film (flat sealing member)

Claims (12)

[Claims] An ink jet recording head mounted on a carriage that scans in the width direction of the recording paper and ejects ink droplets from nozzle openings to form an image on the recording paper; and a flushing drive signal is sent to the recording head. An ink jet recording apparatus, comprising: an ink recovery unit that receives an ink droplet when supplied, disposed on a movement path of the recording head, wherein the ink recovery unit includes a unit box formed in a housing shape, A fan is provided, and the unit box is formed with a receiving opening through which ink droplets ejected from a nozzle opening of the recording head by a flushing operation can pass. A series of air passages are formed so as to be turned up and down in the direction, and the exhaust fan is united. Is disposed at the end portion of the air flow path or air flow path boxes, constituting the ink jet recording apparatus as an air flow towards the end of the air passage is formed from the receiving opening of the unit box. 2. An ink droplet collecting space is formed in the unit box immediately after the receiving opening in the direction of gravity, and the air flow path is directed in the anti-gravity direction immediately after the receiving opening. The ink jet recording apparatus according to claim 1, wherein the ink jet recording apparatus is formed. 3. The ink jet recording apparatus according to claim 2, wherein a waste liquid outlet is formed in a lower bottom portion of the ink droplet collecting space formed immediately after the receiving opening. 4. The ink jet recording apparatus according to claim 1, wherein a plate-like body for further increasing the surface area of the air flow path is arranged in the air flow path. 5. The air flow passage according to claim 4, wherein the plate-shaped members are arranged alternately in the air flow path, and each plate-shaped body is formed so as to meander in the horizontal direction further. Inkjet recording device. 6. The plate according to claim 5, wherein each of the plate-shaped members arranged so as to be staggered in the air flow path is formed such that a tip end of each plate-shaped member is inclined in the direction of gravity. Inkjet recording device. 7. The air flow path according to claim 4, wherein each of the plate-like bodies formed so as to be staggered in the air flow path is disposed in the air flow path in the anti-gravity direction. The ink-jet recording apparatus as described in the above. 8. A waste liquid guiding hole communicating with the ink droplet collecting space portion is formed at a lower bottom portion of a series of air flow paths formed so as to be folded up and down. An ink-jet recording apparatus according to any one of the above. 9. The ink jet recording apparatus according to claim 1, wherein an air filter is disposed in a part of the air flow path. 10. The ink jet recording apparatus according to claim 9, wherein the air filter is disposed immediately before the exhaust fan. 11. The unit box is formed integrally with one side wall, a peripheral side wall connected to the side wall, and an inner wall body forming a series of air flow paths inside the peripheral side wall and facing the one side wall. 11. A box-shaped member having a configuration in which the other side surface is opened, and a sealing member that seals an open end of the box-shaped member to form a housing. An ink jet recording apparatus according to any one of the above. 12. The ink jet recording apparatus according to claim 11, wherein the sealing member is formed of a heat-sealing film, and the heat-sealing film seals an open end of the box-shaped member.