JPH05270006A - Ink jet printer - Google Patents

Abstract

PURPOSE:To make it possible to perform, when a nondelivery state of ink has occurred in a nozzle of a record head, an operation for restoring said state efficiently without needlessly consuming the ink. CONSTITUTION:A plurality of caps for covering the outer periphery of each group of nozzles 5 of a record head 4 are comprised of a restoration cap 19 for performing covering and restoring operations of nozzle and preserving caps 20 which perform only covering operation of nozzle so that a restoring operation is performed only for a group of nozzles 5, wherein a nondelivery state has occurred.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer for recording by ejecting ink from nozzles provided in a recording head, and more particularly to an ink jet printer capable of efficiently performing a nozzle recovery operation. ..

[0002]

2. Description of the Related Art Conventionally, there is known an ink jet printer for performing desired printing on a recording medium such as paper by ejecting ink supplied to a recording head from its nozzle. In principle, an inkjet printer, when dust adheres to the nozzles of the recording head or bubbles occur in the ink flow path inside the head,
A problem of non-ejection of ink occurs.

Therefore, conventionally, by ejecting ink from the ejection port while covering the ejection port of the nozzle provided in the recording head, or by pressurizing the ink tank in the recording head, the ejection port of the nozzle. There is proposed an inkjet printer including a recovery device that removes bubbles in the ink flow path of the recording head by causing the ink to flow out from the ink jet printer.

FIG. 4 shows an example of an ink jet printer equipped with such a conventional recovery device.
A pair of carriage shafts 2, 2 extending in a direction parallel to the axial direction of the platen 1 are arranged in front of the cylindrical platen 1, and can reciprocate along these carriage shafts 2. A carriage 3 is arranged. A recording head 4 capable of performing full-color printing, for example, is mounted on the carriage 3.

The recording head 4 is provided with four nozzle aggregates 5, 5 ... Corresponding to the four color inks for full-color printing so as to face the platen 1, and each nozzle aggregate is arranged. The body 5 is composed of a plurality of nozzles arranged in the vertical direction so as to face the platen 1. Then, these nozzle assemblies 5 are
It is fixed to a head mount 6 supported by the carriage 3.

An inlet 7 having a function as a buffer tank is arranged on the carriage 3 at the back of each nozzle assembly 5 so as to communicate with each nozzle constituting the nozzle assembly 5 and to function as a buffer tank. The ink cartridges 8, 8 ... Of the corresponding color that are detachably mounted on the carriage 3 are communicated with the ink cartridge 7.

On the surface of the head mount 6 facing the platen 1, there is provided a pressurizing port 9 which can be joined to a pressurizing air supply port 18 provided in a cap device 12 which will be described later. The pressure port 9 is connected to all the ink cartridges 8, 8 ... Through a pressure tube 10 and an air pipe 11.

On the other hand, on one side of the platen 1, each nozzle is covered to prevent the ink in the nozzle from drying out when not in use, or bubbles formed in the nozzle or foreign matter clogged in the nozzle. Cap device 1 used for removing
2 are provided. The cap device 12 has a casing 14 in which an opening 13 is formed on the carriage 3 side, and inside the opening 13 of the casing 14, a cap that is movable in the direction in which the recording head 4 is moved toward and away from the recording head 4. A body 15 is provided. This cap body 15
Has a plurality of vertically long caps 16 corresponding to each nozzle assembly 5 of the recording head 4 so as to cover each nozzle assembly 5, and inside each cap 16, A rubber liner 17 is stretched, and this liner 17
Are projected from the inside of the peripheral edge of the cap 16 to the outside so that they can be press-contacted to the outer periphery of each nozzle assembly 5 in a secret manner.

A pressure air supply port 18 connected to a pressure pump (not shown) provided in the cap device 12 is provided on the upper front surface of the cap body 15, and this pressure is applied. The air supply port 18 communicates with the pressurizing port 9 provided in the recording head 4 when the cap device 12 covers the nozzle surface of the recording head 4, and all the ink cartridges mounted on the carriage 3. It is configured so that the inside of 8 can be pressurized at the same time.

In such an ink jet printer, when a non-ejection state of ink occurs due to clogging of nozzles or generation of bubbles in an ink flow path during printing,
The carriage 3 is driven to move the recording head 4 to the cap device 1
2 is moved to a position facing the recording head 4, the cap device 12 is moved toward the recording head 4, and each cap 16 formed on the cap main body 15 covers the nozzle assembly 5 facing the recording head 4. All of the ink cartridges 8 are supplied by driving a pressure pump (not shown) provided in 12 to supply pressure air from the pressure air supply port 18 to the pressure port 9 provided in the recording head 4. Pressurize the ink inside. When the ink in the ink cartridge 8 is pressurized, the ink will flow out from the nozzles of all the nozzle assemblies 5, 5 ... And the air bubbles in the ink flow path will be discharged together with this ink and the non-discharge state will be recovered. Is performed.

[0011]

By the way, in the ink jet printer, the non-ejection state of ink rarely occurs simultaneously for the nozzle aggregates of all colors, and normally, only for the nozzle aggregates 5 of one color. It is common that non-ejection of ink occurs.

However, in the conventional ink jet printer, when an ink non-ejection state occurs, all nozzles are always covered with the cap device 12 and ink is discharged from the nozzles of all colors to recover the non-ejection state. Since such a configuration is adopted, there is a problem that a large amount of ink is unnecessarily consumed due to the ink flowing out from the nozzles that do not need to perform the recovery operation.

The present invention has been made in view of the above-mentioned conventional problems, and when ink is not ejected from the nozzles of the recording head, the recovery work is wasted. It is an object of the present invention to provide an ink jet printer that can be efficiently performed without any need.

[0014]

In order to achieve the above-mentioned object, an ink jet printer of the present invention comprises a recording head having a plurality of nozzle aggregates each including at least one nozzle, and each nozzle aggregate of the recording head. An ink jet printer having a cap device provided with a plurality of caps capable of respectively covering the outer circumference of a body, and a storage cap for covering only the recovery cap and the nozzle capable of performing a nozzle covering and recovering operation of the plurality of caps It is composed of and.

[0015]

According to the present invention, a plurality of caps respectively covering the outer periphery of each nozzle assembly of the recording head provided in the cap device are covered only with a recovery cap capable of performing a recovery operation and a recovery operation and a nozzle. Since it is composed of a storage cap, when an ink ejection failure occurs in a nozzle, a recovery operation is performed by covering only the nozzle in the ejection failure state with a recovery cap and letting the ink flow out. Can be done.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. In addition, about the same structure as the above-mentioned conventional one, the same code | symbol is attached in drawing and the description is abbreviate | omitted.

1 to 3 show one embodiment of the ink jet printer of the present invention, FIG. 1 is a perspective view showing the main part of the overall construction, and FIG. 2 is the ink jet printer of FIG. FIG. 6 is a cross-sectional view showing the structure of a recovery cap provided in the recording head and the cap device of FIG.
FIG. 3 is a sectional view showing the structure of the recording head and the storage cap.

The ink jet printer according to the present embodiment has a recording head 4 in which four nozzle aggregates 5 respectively corresponding to four color inks for full-color printing are arranged so as to face the platen 1, and the recording head 4 is not used. A cap device 12 used for covering each nozzle to prevent the ink in the nozzle from being dried and for removing air bubbles formed in the nozzle and foreign substances clogged in the nozzle is provided. Although it is similar to the conventional one in the point, the structure of the cap body 15 provided in the cap device 12 and the mechanism for pressurizing the inside of the ink cartridge 8 provided in the recording head 4 are different.

That is, the plurality of caps provided on the cap main body 15 cover the nozzle assembly 5 of the recording head 4 and prevent the drying thereof, and have a function of performing the recovery operation, and the recording head 4. Storage cap 20 having only the function of covering the nozzle assembly 5 of FIG. 1 and preventing its drying. In the present embodiment, one of the four caps is the recovery cap 19 and the remaining three. One is a storage cap 20.

Further, the front surface of the cap body 15 is provided with a pressurized air supply port 18 connected to a pressure pump (not shown) provided in the cap device 12 as in the conventional case. However, unlike the conventional one, the position of the pressurized air supply port 18 is not in the center of the cap body 15 but above the recovery cap 19, and the nozzle assembly 5 covered by the recovery cap 19 will be described later. It is configured to pressurize only the ink in the ink cartridge 8 corresponding to.

Further, on the surface of the head mounting base 6 of the recording head 5 facing the platen 1, a pressurizing port 9 that can be joined to a pressurizing air supply port 18 provided in the cap device 12 as in the conventional case. Although the conventional one pressurizes the ink in all the ink cartridges 8 by one pressurizing port 9, in the present embodiment, four inks corresponding to each color are provided. The pressurizing ports 9, 9, ... Are provided above the nozzle assemblies 5, 5 ,.
The pressurizing ports 9, 9 ... Are connected to the ink cartridges 8 of the respective colors via independent pressurizing tubes 10, 10 ... and the air pipes 11, 11 ,. It is configured so that it can be pressurized independently.

Next, the structure of the recording head 4 and the above-mentioned recovery cap 19 and storage cap 20 in this embodiment will be further described with reference to FIGS. 2 and 3.

As shown in FIGS. 2 and 3, the nozzle assembly 5 of the recording head 4 is composed of a plurality of ink flow paths 21 arranged in the vertical direction.
A piezoelectric element 23 for ejecting ink from the nozzle opening 22 at the tip is arranged in the.

Further, as shown in FIG. 2, the recovery cap 19 is provided therein with a wiper 24 for removing dust and the like adhering to the nozzle openings 22 of the recording head 4 by sliding its surface. A communication passage 26 communicating with an atmosphere release valve (not shown) for communicating the space 25 formed by the recovery cap 19 and the surface of the recording head 4 on which the nozzle openings 22 are arranged with the atmosphere. Also, a waste liquid pipe 27 is provided which is connected to a suction means (not shown) for removing the ink flowing out of the space 25 from the nozzle opening 22 by the recovery operation.

A compressed air supply port 18 is provided above the recovery cap 19 of the cap body 15.
The pressurized air supply port 18 is connected to a pressurizing means (not shown) by a pressurized air passage 28.

On the other hand, the storage cap 20 need only have a function of covering the nozzle assembly 5 and protecting it, so that the nozzle opening 22 of the recording head 4 as shown in FIG.
The structure is only provided with a communication passage 30 that communicates with an atmosphere release valve (not shown) for communicating the space 29 formed with the surface on which is arranged with the atmosphere.

Next, the operation of this embodiment will be described.

First, in the standby state in which the printing operation is not performed, the recording head 4 is in a position facing the cap device 12, and each nozzle assembly 5 is covered by the caps in the facing positions. There is. At that time, the nozzle assembly 5 at the right end in FIG. 1 is covered by the recovery cap 19 of the cap device 12, and the other three nozzle assemblies 5 are covered by the storage cap 20, but Since the cap 19 also has a function of protecting the nozzle assembly 5, the nozzle assembly 5 at the right end is maintained in a state of being protected from drying like the other three nozzle assemblies 5. When a printing operation is performed, the covering by the cap is released and the recording head 4 is driven while the carriage 3 moves along the platen 1, whereby ink is ejected from the nozzles and desired recording is performed.

Next, when an ink ejection failure occurs in any of the nozzles during the printing operation, the carriage 3 is driven to recover the nozzle assembly 5 including the nozzle in which the ejection failure occurs. After moving to a position facing the cap 19, the cap device 12 is moved toward the recording head 4 to cover the nozzle assembly 5 with the recovery cap 19 to obtain the state shown in FIG.

After that, the pressurizing means is driven in a state where the communication port 26 is in communication with the atmosphere, and the nozzle in which the non-ejection state of the recording head 4 has occurred through the pressurized air passage 28 and the pressurized air supply port 18. By supplying pressurized air to the pressurizing port 9 corresponding to the nozzle assembly 5, the inside of the ink cartridge 8 is pressurized so that the ink flows out from the nozzle port 22 and the wiper 24 is driven to recover the non-ejection state. Perform recovery operation. The ink that has flowed out into the space 25 of the recovery cap 19 by this recovery operation is removed from this space 25 via the waste liquid pipe 27 by driving the suction means after the communication port 26 is not communicated with the atmosphere. It

At this time, the other three nozzle assemblies 5
Is covered by the storage cap 20 depending on its position,
Or it is in a state where it is not covered by any cap, but in any state these 3
Since no recovery work is performed on one nozzle assembly 5, ink does not flow out from the nozzle assembly 5 other than the nozzle assembly 5 including the nozzle in which the ejection failure state has occurred. As described above, according to the present embodiment, the four caps provided on the cap device 12 corresponding to the four nozzle assemblies 5 of the recording head 4 are provided with the cap 19 and the nozzles for the purpose of covering and recovering the nozzles. And a cap 20 for storage that can cover only the above, and when a nozzle is in a non-ejection state, the recovery operation can be performed only on the nozzle assembly 5 including the nozzle. Ink does not flow out from the nozzle assembly that has not occurred, and wasteful consumption of ink by the recovery operation can be prevented.

In the above-described embodiment, the description has been given by taking the ink jet printer provided with a plurality of nozzle assemblies each having a plurality of nozzles as an example. However, the present invention is not limited to this, and at least two. The present invention can be applied as long as it has three or more nozzles and caps, and two or more recovery caps may be provided. Further, it goes without saying that the recovery mechanism for the non-ejection state may be a mechanism for causing the ink to flow out by sucking the ink using a negative pressure from the nozzle port, instead of pressurizing the ink. It is possible.

[0033]

As described above in detail, according to the ink jet printer of the present invention, a plurality of caps respectively covering the outer circumferences of the nozzles of the recording head provided in the cap device perform nozzle covering and recovery operations. By configuring the recovery cap to be obtained and the storage cap that covers only the nozzle, when the ink ejection failure occurs in the nozzle, the recovery operation is performed only to the nozzle in the ejection failure state. Therefore, it is possible to effectively recover the non-ejection state without the ink being wastefully consumed by the recovery operation from being ejected from the nozzles that do not need to perform the recovery operation.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of the overall configuration of an inkjet printer of the present invention.

2 is a cross-sectional view showing a structure of a recovery cap provided in a recording head and a cap device of the inkjet printer of FIG.

3 is a cross-sectional view showing the structure of a storage cap provided in the recording head and the cap device of the inkjet printer of FIG.

FIG. 4 is a perspective view showing a main part of the overall configuration of a conventional inkjet printer.

[Explanation of symbols]

 1 Platen 2 Carriage Shaft 3 Carriage 4 Recording Head 5 Nozzle Assembly 8 Ink Cartridge 9 Pressurizing Port 10 Pressurizing Tube 11 Air Pipe 12 Cap Device 15 Cap Body 18 Pressurized Air Supply Port 19 Recovery Cap 20 Storage Cap

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B41J 2/185 8306-2C B41J 3/04 102 R

Claims (1)

[Claims] 1. An ink jet having a recording head provided with a plurality of nozzle assemblies each comprising at least one nozzle, and a cap device provided with a plurality of caps capable of covering the outer circumference of each nozzle assembly of the recording head. In the printer, an ink jet printer characterized in that the plurality of caps are composed of a recovery cap capable of performing nozzle covering and recovery operations and a storage cap only covering nozzles.