JPH1076677A - Ink jet recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit satisfactory restoring operation without accompanying the enlargement of the size of device or any complicated constitution and without generating any trouble such as the deposit of ink and the like by a method wherein the device is controlled so as to effect first preliminary discharging and second preliminary discharging for washing deposit adhered to a preliminary discharging receiving unit. SOLUTION: An ink jet recording device is provided with a means to control the device so as to effect first preliminary discharge for restoring the faulty discharge of ink of a recording head 2 and second preliminary discharge for washing deposit adhered to a preliminary discharge receiving unit while the amount of ink, discharged by the second preliminary discharge, is sufficiently much amount with respect to the amount of ink discharged by the first preliminary discharge or an amount of a degree that the ink flows down after being collided against a preliminary discharge receiving unit wall surface and it corresponds to an amount of 500 shots per one nozzle or more, for example. In this case, the number of shot of first and second preliminary discharge is determined properly by the characteristics of the recording device or various conditions such as the number of nozzles of the recording head 2, the discharging amount of ink per one nozzle, the viscosity or drying speed of ink and the like.

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, and more particularly, to an ink jet recording apparatus used in a printer, a facsimile, or the like which performs recording by discharging ink.

[0002]

2. Description of the Related Art In this type of ink jet recording apparatus, for example, ink is supplied to an ink jet recording head from a cartridge type ink tank filled with recording ink and discharged from an ejection port provided in the recording head. The ink is ejected as recording droplets toward the recording material, and recording is performed.

In such an ink jet recording apparatus, dust or bubbles may be mixed in an ink supply system from an ink tank to a recording head, and an ink ejection port provided in the recording head and a liquid passage communicating with the ink ejection port may be provided. In general, since the inside diameter is as small as several microns to several tens of microns, if dust and air bubbles are introduced into the liquid path of the recording head, they adhere to the liquid path and hinder the flow of ink, There is a fear that the ink ejection efficiency may be reduced, or in a severe case, clogging may occur to cause ink ejection failure. In addition, when the recording apparatus is not filled with the ink and the ink is not ejected for a long time, there is a fear that components constituting the ink may precipitate and cause abnormal ink ejection.

[0004] In order to solve these problems,
At the time of recording, it is desirable to maintain the ink ejection from the recording head in a good state, and as a recovery means therefor, a pressure recovery means, a suction recovery means and the like have been employed. Among these, the suction recovery means sucks ink from the discharge port using a suction pump or the like while the peripheral portion of the ink discharge port is closed with a cap, and fixes ink, air bubbles, dust, and the like that accumulates in the liquid path. And other obstacles are removed from the fluid path.

In such an ink jet recording apparatus, a blade made of an elastic material such as rubber or the like is used to remove foreign matter which hinders ink ejection such as ink and dust attached to the ejection opening surface. A process of wiping and cleaning the discharge port surface, that is, a wiping operation is performed.

Further, in order to prevent drying and sticking of the nozzles which are not frequently used during printing, ejection as a recovery operation, ie, preliminary ejection operation, is performed at regular intervals. In this method, ink is ejected from all nozzles to predetermined positions other than the recording section at intervals (for example, every 20 seconds) at which ink in nozzles that are not ejected does not dry. Further, in order to stabilize the discharge after the wiping process by the blade, the preliminary discharge may be performed even after the wiping operation.

[0007] These series of recovery means are generally performed by a recovery device including a cap, a suction pump, a blade, and the like provided outside the recording range. The recovery device is also provided with the preliminary ejection operation. It is generally performed in a preliminary discharge receiving portion which is an opening portion. The ink discharged to the preliminary discharge receiving portion is transmitted and held by a waste ink absorber provided below the recovery device by a flow path led from the opening. The waste ink flow path has a simple and low-cost configuration in which an opening portion surrounded by a wall is simply continuous from the receiving portion to the absorber.

[0008]

However, in the conventional ink jet recording apparatus as described above, the ink which has been ejected from the preliminary ejection receiving portion or the wall constituting the flow path and receives the ink which flows down naturally is used as the ink jet recording device. Because it is configured to be held by the waste ink absorber below, when using a certain kind of ink, for example, an ink with improved fixability to plain paper or water resistance, only a small amount of ejected ink such as preliminary ejection is used. When the ink adheres to the wall, it dries before flowing down, and the repetition causes a problem that the ink is gradually deposited on the wall.

Particularly, in the case where a recording head having an ejection direction at an angle of, for example, about 10 ° is used due to a restriction imposed by a processing method of forming a nozzle of the recording head, the ejection is received on a wall surface relatively close to the receiving portion. Therefore, there is a fear that if the ink is deposited there, the receiving portion may be closed in a short time with respect to the life of the apparatus.

In order to solve this problem, it is conceivable that the ejection receiving portion and the flow path are provided sufficiently large. However, a space is required in the width direction especially for a recording head having an ejection angle. This necessitates a reduction in the size and cost of the apparatus.

Therefore, an object of the present invention is to pay attention to the above-mentioned conventional problems, and to solve the problems, without enlarging the device and making it complicated, without causing the above-mentioned inconvenience. An object of the present invention is to provide an ink jet recording apparatus capable of performing a recovery operation.

[0012]

In order to achieve the above object, according to the present invention, there is provided a recording head which discharges ink toward a recording material to perform recording, and a preliminary discharging operation which is a non-recording operation. In an ink jet recording apparatus having a preliminary ejection receiving section for receiving ejected ink, a first preliminary ejection for recovering ink ejection failure of the recording head and cleaning of deposits attached to the preliminary ejection receiving section And a means for controlling to perform the second preliminary discharge for performing the second preliminary discharge.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the amount of ink discharged by the second preliminary discharge is smaller than the amount of ink discharged by the first preliminary discharge. It has a number of configurations, a means for counting the number of times of the first preliminary ejection or the amount of ink to be ejected, and a configuration for performing the second preliminary ejection when a predetermined number of times or a predetermined amount of ink is reached. The above object is achieved by providing a means for counting the number of the recording materials, and performing the second preliminary ejection when the number reaches a predetermined number.

[0014]

According to the configuration of the present invention as described above, it is possible to prevent the preliminary discharge receiving portion from being blocked, etc., without particularly increasing the size of the apparatus and complicating the configuration.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings based on a plurality of examples.

[0016]

【Example】

(Embodiment 1) FIG. 1 is a schematic perspective view of an ink jet recording apparatus according to a first embodiment of the present invention. Here, an ink jet recording apparatus is shown in which an ink cartridge containing a supply ink and a recording head are formed in an integral cartridge form and an ink jet cartridge is mounted on a carriage to perform recording.

In FIG. 1, reference numeral 1 denotes a recording material (hereinafter, referred to as a "recording sheet") such as a sheet of paper or a thin plastic sheet. The recording sheet 1 is a sheet feeding device such as a manual feed or cut sheet feeder (not shown). A predetermined interval, for example, 0.5 to 2.
The sheet is sent at an interval of about 0 mm, and is set at a recording start position by rotation control of a sheet feed roller (not shown). Reference numeral 3 denotes a carriage on which the recording head 2 is mounted and which is movably guided along guide shafts 4 and 5;
A timing belt connected to the carriage 3 for moving and scanning the carriage 3, a motor 7 for driving the timing belt 6, and an idle pulley 8.

On the other hand, the recording sheet 1 is held on a platen 9 by a sheet holding plate 10 and the carriage 3
Each time one scan is recorded on the recording sheet 1 by the moving scan, the sheet is fed in the direction perpendicular to the scanning direction by that amount, and the recorded recording sheet 1 is discharged by the discharge roller 1.
1 is held between the spur roller 12 and the spur roller 12 interlocked therewith and discharged. In some cases, a heater is provided on the platen 9 to fix the ink on the recorded recording sheet 1.

Reference numeral 13 denotes a recovery device according to the embodiment of the present invention, which is provided at a position facing the recording head outside the recording area outside the platen 9. The recovery device 13 will be described later in detail. Reference numeral 14 denotes a rotation knob for manually feeding the recording sheet 1.

The recording head 2 ejects ink by using thermal energy. As shown in FIG. 2, a schematic partial perspective view of an ink ejection section is provided in the ejection unit 20 of the recording head 2. An electrothermal conversion element 23 is provided in a liquid passage 22 communicating with each ink ejection port 21. Then, the thermal energy generated in response to the electric signal supplied to the electrothermal conversion element 23 causes bubbles in the ink in contact with the liquid path 22 due to film boiling, and utilizes the pressure change generated by the growth and contraction. And the ink ejection port 21
, Ink is ejected from the printer and ejected as flying ink droplets on the recording sheet 1 to perform dot recording. Still further, in FIG.
2 is a common liquid chamber for leading ink to the second liquid chamber. Here, the ink discharge ports 21 and the liquid paths 22 are formed at a predetermined pitch in a direction crossing the scanning direction of the carriage 3 shown in FIG.

Further, the ink discharge port 21 of the recording head 2 in this embodiment has a plurality of nozzles of 70 nozzles or more in the sub-scanning direction. In addition, the speed of the recording apparatus is increased.

FIG. 3 is a schematic perspective view of an example of the configuration of the recovery device 13 according to the present invention.

In FIG. 3, inside the recovery device 13,
A pump 1302 for generating a suction negative pressure by reciprocating the piston 1301 is provided. A cap 1303 made of an elastic material such as rubber is provided at a suction port (not shown) provided in the pump 1302. Installed. With the peripheral portion of the ink discharge port of the recording head 2 closed with the cap 1303, the pump 1302
By generating a suction pressure in the above, the ink is sucked from the ink discharge port of the recording head 2 and dust and the like accumulated in the liquid path are removed from the liquid path. The ink sucked by the pump 1302 is discharged and held by a waste ink absorber 1304 provided below the recovery device 13. Reference numeral 1305 denotes a blade which is made of an elastic member such as rubber and removes extra ink droplets, dust, and the like around the ejection openings of the recording head 2. That is, when the blade 1305 is at a position where it is pressed against the ejection surface of the recording head 2, the recording head 2
By moving the carriage 3 so that the ink passes over the front surface of the blade 1305, ink and impurities attached to the ejection surface are removed, and the ejection stability of the recording head 2 is ensured.

Reference numeral 1306 denotes a pump cam driven by a drive source (not shown) to move the piston 1301 up and down to generate suction pressure in the pump 1302.

Further, the recovery device 13 has a preliminary discharge receiving section 1 for receiving discharge (preliminary discharge) as a recovery operation.
307 are provided. That is, a predetermined ejection is performed after the carriage 3 moves so that the recording head 2 comes to a position facing the preliminary ejection receiving unit 1307, and the ink ejected to the preliminary ejection receiving unit 1307 is discharged from the discharge passage. The waste ink is discharged from 1308 to the waste ink absorber 1304.

Here, the state of the ink ejected to the preliminary ejection receiving portion 1307 will be described in detail. FIG. 4 is a schematic side view of the recovery device 13 illustrating an ideal flow of the discharged ink, and FIG. 5 is a schematic plan view of the recovery device 13 illustrating the flow of the discharged ink, which is a problem. .

In FIG. 4, the recording head 2 mounted on the carriage 3 is provided with a preliminary ejection receiving portion 13 of a recovery device 13.
Preliminary ejection is performed at a position opposite to 07. The ejected ink droplet a flows in the direction b in the wall behind the preliminary ejection receiver, and is guided from the discharge channel 1308 to the waste ink absorber 1304.

On the other hand, in FIG. 5, when there is an ejection angle of the ink ejected from the recording head 2, the ink ejected to the preliminary ejection receiving portion 1307 is moved to the side portion inside the preliminary ejection receiving portion before reaching the inner wall. Will be hit. Here, if the ink used is an ink with improved fixability to plain paper or water resistance, if only a small amount of discharged ink such as preliminary discharge adheres to the wall, it will dry before flowing down,
Ink gradually accumulates on the wall of c,
In the worst case, there is a fear that the receiving portion may be blocked by the grown deposit.

The problem here is that the ink is ejected intermittently and by a small amount of preliminary ejection (for example, about 10 to 100 shots per nozzle).
It has been found that if the amount falls, it hardly accumulates.

Therefore, in the ink jet recording apparatus according to the embodiment of the present invention, the first preliminary ejection for recovering the ejection failure of the ink of the recording head and the cleaning for the deposit adhering to the preliminary ejection receiving portion. Means for controlling the second preliminary ejection to be performed, and the amount of ink ejected by the second preliminary ejection is sufficiently larger than the amount of ink ejected by the first preliminary ejection. The amount is such that it falls down on the wall surface of the preliminary discharge receiving portion, for example, 500 or more per nozzle.

The number of first and second preliminary ejections depends on the characteristics of the printing apparatus, that is, the number of nozzles of the printing head, the ejection amount per nozzle, or the ink viscosity and drying speed, and other conditions. It can be determined as appropriate.

Next, an example of the control means for performing the second preliminary discharge according to the present invention will be described with reference to the operation sequence flowchart of FIG.

In FIG. 6, after the control is started, in step S1, a counter for counting the number of times of the first preliminary ejection is reset. Thereafter, in step S2, the first preliminary ejection is performed in accordance with the printing operation, and the number of times is counted by a counter. In step S3, it is determined whether the number of preliminary ejections recorded in the counter has reached a predetermined number (for example, 10 times).
And the printing operation and the preliminary ejection are repeated. If it is determined in step S3 that the predetermined number of times has been reached, there is a possibility that the ink deposited by the preliminary ejection has started to be deposited to some extent in the preliminary ejection receiving unit. A large amount of discharge (second preliminary discharge) is performed.
Thereafter, returning to step S1, the counter is reset again, and recording is performed while repeating the operation up to now.

(Other Embodiment 2-4) Next, another embodiment of the present invention will be described.

In the first embodiment, step S in FIG.
Although the content of the counter set at 1 is the number of ejections of the first preliminary ejection, as a second embodiment, the counter is configured so as to count the amount of ejected ink converted from the number of ejections, and to set a predetermined amount of ink. May be controlled so as to perform the second preliminary discharge at a timing when it is assumed that the second preliminary discharge adheres to the preliminary discharge wall surface.

Further, as a third embodiment, the content of the counter set in step S1 of FIG. 6 is set to the number of recording materials used for recording, and the second preliminary ejection is performed when a predetermined number of recordings is reached. May be controlled as follows. This is an effective control means particularly for a recording apparatus which performs control such that preliminary discharge is performed at the head of each page.

Further, as a fourth embodiment, control may be performed such that the second number of preliminary ejections is changed according to the type of ink used. The fourth embodiment will be described with reference to the operation sequence flowchart of FIG. Step S
Steps S1 to S3 in FIG. 6 are performed from 21 to S23.
When it is determined in step S23 that the predetermined number of preliminary ejections has been reached, the flow advances to step S24 to determine the type of print head currently used. If the installed recording head is a normal black ink head,
Proceeding to step S25, the second preliminary ejection is performed for 500 shots.

On the other hand, when it is determined in step S24 that the mounted head is a head for color ink, if it is assumed that cleaning of deposits of color ink requires a larger amount of ink than ordinary black ink, the second Preliminary ejection is performed 1000 times. This is effective control means for a printing apparatus that performs monochrome printing and color printing by replacing the ink jet cartridge, and is a control method suitable for a case where the characteristics differ depending on the type of ink.

(Embodiment) In each of the embodiments described above, the ejection unit of the recording head 2 and the ink tank unit are integrated, and when the ink runs out, the disposable unit is replaced together with the recording head 2. Although the description has been given of the case of the recording apparatus in which the ink-jet cartridge of the shape is mounted on the carriage 3 as an example, the application of the present invention is not limited thereto, and the ejection unit and the ink tank may be independently provided on the carriage 3. An ink jet recording apparatus which is mounted on the top and is configured so that only the ink tank can be replaced when the ink runs out, or only an ejection unit is mounted on the carriage 3 and a tube is provided from an ink tank arranged at another place in the recording apparatus. The present invention can be applied to any of the fixed tank type ink jet recording apparatuses that supply ink to the discharge unit via the like. It is a matter of course that the same effect can be obtained.

Further, in each of the above embodiments, a case is described in which the recording head is used to increase the recording speed by providing a plurality of nozzles having 70 or more nozzles in the sub-scanning direction. The present invention can be applied to an ink jet recording apparatus such as a recording head having a discharge port of less than 70 nozzles or a full line head having a larger number of nozzles. An effect can be obtained.

In each of the above embodiments, an ink jet recording apparatus using one recording head has been described as an example. However, the present invention is not limited to a plurality of recordings such as color recording or gradation recording. The same can be applied to the case of an ink jet recording apparatus using a head, and the same effect can be achieved. The present invention also relates to an ink jet recording apparatus using a recording means (recording head) using an electromechanical transducer such as a piezo element, or an ink which solidifies at room temperature or below. The present invention can also be applied to a case where an ink that liquefies for the first time by energy is used.

In addition, the form of the ink jet recording apparatus according to the present invention can be used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, a facsimile apparatus having a transmitting / receiving function, a document. It may be in the form of a word processor having a creation function.

[0043]

As described above, according to the present invention,
Means for controlling so as to perform a first preliminary discharge for recovering ink discharge failure of the recording head and a second preliminary discharge for cleaning deposits attached to the preliminary discharge receiving portion; The amount of ink ejected by the second preliminary ejection is
A configuration in which the number of inks ejected by the first preliminary ejection is larger than the amount of ink ejected by the first preliminary ejection; The apparatus has a configuration for performing the second preliminary ejection, a means for counting the number of used recording materials, and a configuration for performing the second preliminary ejection when a predetermined number of recording materials is reached. It has become possible to provide an ink jet recording apparatus that can prevent a failure caused by blocking of a preliminary ejection receiving portion by ink deposited by preliminary ejection without using a complicated configuration.

[Brief description of the drawings]

FIG. 1 is a perspective view of an inkjet recording apparatus according to a first embodiment.

FIG. 2 is a schematic partial perspective view of an ink ejection unit in FIG. 1;

FIG. 3 is a schematic configuration perspective view of a recovery device according to the first embodiment.

FIG. 4 is a schematic side view of the flow of ejected ink by the recovery device of FIG. 3;

FIG. 5 is a schematic plan view of the flow of the ejected ink in FIG.

FIG. 6 is a flowchart of a preliminary ejection operation sequence according to the first embodiment.

FIG. 7 is a flowchart of a preliminary ejection operation sequence according to a fourth embodiment.

[Explanation of symbols]

 2 Recording Head 3 Carriage 13 Recovery Device 1304 Waste Ink Absorber 1307 Preliminary Discharge Receiving Unit 1308 Drain Flow Path

Claims (6)

[Claims] 1. An ink jet recording apparatus comprising: a recording head that discharges ink toward a recording material to perform recording; and a preliminary discharge receiving section that receives ink discharged by a preliminary discharge operation that is a non-recording operation. Means for controlling so as to perform a first preliminary ejection for recovering ink ejection failure of the recording head and a second preliminary ejection for cleaning deposits adhered to the preliminary ejection receiving portion. An ink jet recording apparatus comprising: 2. The ink jet recording apparatus according to claim 1, wherein an amount of ink ejected by said second preliminary ejection is larger than an amount of ink ejected by said first preliminary ejection. 3. A method for counting the number of times of the first preliminary ejection or the amount of ink to be ejected, and performing the second preliminary ejection when a predetermined number of times or a predetermined amount of ink is reached. 3. The ink jet recording apparatus according to claim 1, wherein 4. The apparatus according to claim 1, further comprising means for counting the number of used recording materials, wherein the second preliminary ejection is performed when the number reaches a predetermined number. An inkjet recording apparatus according to any one of the above. 5. The recording head according to claim 1, wherein the recording head ejects ink by using thermal energy, and includes a thermal energy conversion element for generating thermal energy to be applied to the ink. Item 5. An ink jet recording apparatus according to any one of Items 1 to 4. 6. The ink jet recording apparatus according to claim 1, wherein the recording head includes a plurality of nozzles of 70 or more in a sheet feeding direction of the recording material.