JPH11342621A - Ink jet recording apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiping mechanism capable of executing the wiping operation with an equal condition with respect to the discharging opening arrangement direction of an ink jet recording head with a small driving force. SOLUTION: The length 1 of a wiping roller 3 for the wiping operation of a face surface 1f provided with discharging openings of a recording head 1 has a size shorter than the discharging opening arrangement length L of the recording head 1 as well as it is engaged with a lead screw 4 having both ends fixed, elongating parallel with respect to the discharging opening arrangement direction. The wiping operation of the face surface 1 is executed by rotation of the wiping roller 3 according to the driving force of a motor 6 for transmitted via a cleaner roller 5. Further, the wiping roller 3 moves along the lead screw 4 according to the interaction between the rotation and a groove of the lead screw 4 so that the wiping operation is executed for all the discharging openings provided in the range of the length L. Accordingly, the pressure of contact of the wiping roller 3 to the face surface 1 can be evened easily, and further, the driving force thereof can be made smaller.

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 a so-called full multi-type recording head in which ink discharge ports are arranged corresponding to the width of a recording medium being conveyed. It concerns the mechanism.

[0002]

2. Description of the Related Art As one of ejection recovery processes for an ink jet type recording head, a surface (hereinafter, also referred to as a "face surface") on which an ink ejection port of the recording head is arranged is wiped with a predetermined member (wiping). It is known to do. By this wiping operation, it is possible to remove water droplets and ink droplets adhered to the face surface, and prevent adverse effects such as deflecting the ejection direction near the ink ejection port. When performing this kind of wiping operation on a full multi-type recording head, by relatively moving the recording head and a blade made of a material such as rubber, a mechanism for performing a wiping operation of the face surface by the blade, In general, a mechanism for rotating the roller-shaped wiping member while pressing it against the face surface, or a combination of these mechanisms is generally used. In particular, the latter mechanism is suitable for removing thickened ink on the face surface.

FIG. 4 is a schematic perspective view showing an example of a mechanism for the latter wiping operation. In the figure, when performing a wiping operation, a full multi-type recording head 1 moves downward in the figure and a wiping roller 3 provided in a cap case 2 comes into contact with a face surface thereof. Is rotated by the driving force of the motor 6 to perform the wiping operation. When performing such a wiping operation, a predetermined amount of ink is ejected from the recording head 1 to the wiping roller 3, whereby the wiping roller 3 and the like are pre-wetted to increase the viscosity of the ink on the face surface. There is also a case where the removability is improved.

[0004]

However, the conventional wiping mechanism described above may cause some problems as described below.

[0005] (1) In either case of a mechanism using a blade or a mechanism using a wiping roller, ink may remain on the blade or the wiping roller, and the next wiping operation may be performed in a state where the ink has dried and solidified. This may damage the discharge port on the face surface and its vicinity.

(2) In any mechanism using a blade or a wiping roller, a blade or a roller covering the entire discharge port array is used, and a wiping operation is performed at once for the entire discharge port row. In addition, the pressure distribution of the wiping member such as a roller is not uniform, and the wiping conditions may vary depending on the position of the discharge port. Particularly, depending on the rigidity of the wiping member, the wiping member may not be able to perform a sufficient wiping operation at a central portion of the discharge port array due to a decrease in the contact pressure.

(3) Further, since the wiping operation is performed once for the entire discharge port as described above, the driving force for the wiping operation becomes relatively large, thereby increasing the size of the apparatus and increasing power consumption. May also bring.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to perform a wiping operation under uniform conditions with respect to the arrangement of ejection ports of a recording head. Another object of the present invention is to provide an ink jet recording apparatus which requires a small driving force for the operation and can perform a wiping operation without damaging the face surface.

[0009]

According to the present invention, there is provided:
In an ink jet recording apparatus that performs recording by ejecting ink from a recording head to a recording medium using a recording head provided with a plurality of ink ejection ports, the length of a range in which the plurality of ink ejection ports of the recording head are arranged is determined by A wiping roller having a short length, the wiping roller being rotated to perform a wiping operation on a surface of the recording head on which the plurality of ink discharge ports are provided, and the wiping roller is rotated by the plurality of ink discharge ports. A wiping unit that moves in the arrangement direction of the outlets, and a wiping roller of the wiping unit and a recording head that are relatively moved to make contact with the wiping roller and the surface on which the plurality of ink ejection ports are disposed. And moving means.

Preferably, the wiping means transmits a driving force for rotating the wiping roller via a cleaner roller which rotates in contact with the wiping roller.

According to the above arrangement, since the length of the wiping roller is smaller than the arrangement length of the ink ejection ports, the pressure at the time of performing the wiping operation by contacting the ejection port arrangement surface can be made uniform. And the conditions for the wiping operation when the roller is moved along the discharge port arrangement can be made constant. Further, the pressing force of the entire wiping roller can be reduced, and the driving force for rotating the wiping roller can be relatively small. Further, when the driving force for rotating the wiping roller is transmitted via the cleaner roller, it is possible to remove ink droplets and the like attached to the wiping roller by the cleaner roller in accordance with the transmission operation.

[0012]

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

(First Embodiment) FIG. 1 is a schematic perspective view showing the relationship between a recording head and an ejection recovery mechanism in an ink jet printer according to an embodiment of the present invention.

In FIG. 1, a recording head 1 is a so-called full multi-type head in which ink discharge ports (not shown) are arranged in a range corresponding to a recording width of a recording sheet P conveyed for recording. is there. The recording head according to the present embodiment uses thermal energy generated by an electrothermal conversion element provided in a liquid path corresponding to each ink ejection port to generate bubbles in the ink, and ejects the ink by the pressure. is there. The recording head 1 has a surface on which the ejection ports are provided (hereinafter, also referred to as a “face surface”) opposed to a sheet of paper P as a recording medium, whereby ink ejected from each ejection port is placed on the sheet of paper P. The dots can be formed by attaching them. The paper P is transported by a transport mechanism (not shown) in a direction perpendicular to the arrangement direction of the ink discharge ports in the print head in synchronization with the above-described ink discharge from the print head. It should be noted that a known mechanism for conveying the recording paper can be used, and therefore illustration and description thereof are omitted.

The recording head 1 is provided so as to be movable in the vertical direction indicated by an arrow A in the figure, and performs a recording operation at the lowest position in the moving range. At this time, the recording paper P keeps a predetermined amount of gap (about 0.1 mm in the present embodiment) with the face surface of the recording head 1. On the other hand, during a capping or wiping operation during non-recording (hereinafter also referred to as “wiping”), the recording head 1 comes into contact with the cap case 2 at a position above the lowermost position, thereby covering the face surface. Will be In order to enable such an arrangement relationship, the cap case 2 moves along with the above-described movement of the recording head 1 in the direction of the arrow A, and the retracted position when the recording head 1 moves to the lowermost position; Is provided so as to be movable in the direction indicated by arrow B in the figure between the above-mentioned contact positions. The position shown in FIG. 1 shows a state in which the cap case 2 has moved rightward in order to contact the recording head 1 and the recording head 1 has been lowered accordingly. Also, during such a non-printing operation, the recording paper P is not normally conveyed. The recording paper P does not exist on the transport path.

The mechanism itself for moving the recording head 1 and the cap case 2 described above is as follows.
There is no difference from the conventional example shown in FIG. 4, and the illustration and description thereof are omitted here.

FIG. 2 is a cross-sectional view showing details of the inside of the cap case. A mechanism such as wiping according to the present embodiment will be described with reference to FIGS.

A lead screw 4 is provided in the cap case 2 so as to extend in parallel with the direction of arrangement of the ejection ports in the recording head 1. Both ends of the lead screw 4 are fixed on both sides of the cap case 2 by screws. The wiping roller 3 has a cylindrical shape, and its length 1 is shorter than the discharge port arrangement width L of the recording head, and its length takes into account pressure and the like when the wiping roller 3 comes into contact with the face surface, as described later. Is determined. The wiping roller 3 can rotate and move along the lead screw 4 by engaging with the lead screw 4. That is, the wiping roller 3 has two layers concentrically, and its outer cylindrical portion is made of a porous material such as Rubicell (manufactured by Toyo Polymer Co., Ltd.). Ink absorption can be performed. The inner cylindrical portion of the wiping roller 3 has a bushing portion having a hole formed at the center thereof. The hole is fitted to the lead screw 4 and a pin (not shown) provided in the bushing portion is connected to the lead screw 4.
Engages with the groove. This allows the wiping roller 3 to move along its own lead screw by rotating the wiping roller 3 as described later. The moving amount of the wiping roller 3 is set to L + l or more so that the wiping roller 3 can pass through each discharge port under the same conditions.

The cleaner roller 5 extends in parallel with the lead screw 4, and both ends thereof are rotatably supported by both sides of the cap case. Also, the cleaner roller 5
A gear for receiving the driving force of the motor 6 is attached to one end thereof, so that the gear can be rotated by the driving force of the motor 6. The cleaner roller 5 and the wiping roller 3 are arranged in a positional relationship such that they press against each other in the radial direction to cause a certain degree of deformation of the outer cylindrical portion of the wiping roller 3.

The portion of the cap case 2 which comes into contact with the recording head 1 has a stepped portion, and the face surface 1 can be capped by bringing the stepped portion into contact with the recording head 1. By keeping the distance to the wiping roller 3 constant, the wiping conditions at the time of capping can be made uniform. Then, in this sealed state, the wiping roller 3 can come into contact with the face surface 1f with a predetermined deformation as shown in FIG.

When wiping is performed based on the above-described configuration, the above-described recording head 1 and cap case 2 are used.
With each movement, a cap state as shown in FIG. 2 is obtained. In this state, the cleaning roller 5 is rotated by driving the motor 6 to rotate the wiping roller 3 which comes into pressure contact with the cleaning roller 5. This rotation causes the wiping roller 3 to wipe the face surface 1 f of the recording head 1. Can be. Since the outer cylindrical portion of the wiping roller 3 comes into contact with the face surface with a certain deformation, the wiping range of the face surface 1f can be a portion where the discharge ports are arranged and the vicinity of both sides thereof. The ink or the like adhering to the discharge port and its vicinity by this wiping is absorbed and removed by the outer cylindrical portion of the wiping roller 3, and thereafter, the removed ink and the like attached to the wiping roller 3 are scraped off by the cleaner roller 5, and the surface thereof is removed. Be cleaned. Then, waste ink or the like generated by the wiping described above is guided to a predetermined portion of the apparatus via the drain 7. Further, with the rotation of the wiping roller 3, the interaction between the groove of the fixed lead screw 4 and the pin provided on the rotating wiping roller 3 causes the wiping roller 3 to move along the fitted lead screw 4. Moving. Note that the direction of this movement is determined by the rotation direction of the wiping roller 3. Therefore, by controlling the rotation direction of the motor 6 together with its driving, the wiping roller 3 can reciprocate along the lead screw 4. When performing wiping, wiping can be performed while the wiping roller 3 is positioned at one end of the lead screw in advance and moved toward the other end. Alternatively, wiping may be performed by reciprocating, and the number of movements can be determined according to the specifications of the apparatus.

As described above, according to the present embodiment, by using the wiping roller having a length shorter than the arrangement length of the ejection openings in the recording head, the pressure on the face surface of the wiping roller during wiping can be reduced. It is easy to make it constant throughout, and the driving force of the wiping roller can be relatively small. further,
Since the driving force for the rotation of the wiping roller is transmitted through a cleaner roller that cleans the wiping roller, the surface of the wiping roller is always cleaned, and ink remains on the surface and increases. Problems such as sticking and damaging the face surface can be prevented beforehand.

In the above configuration, the contact state between the recording head 1 and the cap case 2 where wiping is performed is as follows.
This is a state adopted also in the case of capping for preventing the evaporation of ink moisture through the ink discharge port and suppressing the viscosity of the ink. That is, in this capping state, the wiping roller 3 is not rotated and is moved to a predetermined portion, and the end of the face surface 1f is sealed by the stepped portion of the cap case 2 or the predetermined air communication is established. Maintain the associated high humidity condition.

(Second Embodiment) FIG. 3 is a schematic sectional view showing a configuration inside a cap case according to a second embodiment of the present invention.

As is clear from the drawing, the present embodiment
This embodiment is different from the first embodiment in that a mechanism for cleaning the wiping roller 3 with a liquid via the cleaning roller 5 is added. That is, a cleaning liquid such as water is injected from the injection port 8, whereby a part of the cleaning roller 5 can be immersed in the cleaning liquid. As a result, the cleaning roller 5
Is pressed against the wiping roller 3 in a state of being wet with the cleaning liquid,
The cleaning of the wiping roller 3 is performed by this pressure contact, and the wiping roller 3 rotates while absorbing the cleaning liquid, so that the face surface 1f can be wiped with the cleaning liquid.

Although the above-described embodiment relates to an ink jet printer, it is obvious that the application of the present invention is not limited to this. The inkjet recording apparatus of the present invention can be applied as a recording section of a copying machine, a facsimile apparatus, in addition to the above-described printer,
The present invention is applicable not only to the recording medium but also to an apparatus that performs recording on OHP paper, cloth, or the like.

(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 discharging ink, 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 type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal on a one-to-one basis.
This is effective because air bubbles inside can be formed. The liquid (ink) is ejected through the 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 bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. 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 configuration (a linear liquid flow path or a right-angled liquid flow path) of a discharge port, a liquid path, and an electrothermal converter as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat. No. 44,558 which disclose a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 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 aperture for absorbing a pressure wave 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.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed 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.

It is preferable to add ejection recovery means for the recording head, preliminary auxiliary means, and the like as the constitution of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, the recording head is heated using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer, another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.

The types and the number of recording heads to be mounted are, for example, not only those provided for one color ink but also a plurality of inks having different recording colors and densities. 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 recording modes of full color by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. 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 solidifying when it reaches 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
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent Publication No. 1260, it is also possible to adopt a form in which the sheet is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet. 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 only used as an image output terminal of an information processing apparatus such as a computer, but also for a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. It may take a form.

[0036]

As described above, according to the present invention,
Since the length of the wiping roller is smaller than the array length of the ink ejection ports, it is easy to make the pressure when the wiping operation is performed by bringing the roller into contact with the ejection port arrangement surface, and this roller is arranged in the ejection port array. Along, the condition of the wiping operation at the time of moving can be a certain condition. Further, the pressing force of the entire wiping roller can be reduced, and the driving force for rotating the wiping roller can be relatively small.
Further, when the driving force for rotating the wiping roller is transmitted via the cleaner roller, it is possible to remove ink droplets and the like attached to the wiping roller by the cleaner roller in accordance with the transmission operation.

As a result, wiping can always be performed under uniform conditions, and the size and cost of the apparatus can be reduced. Further, it is possible to prevent a problem such as damage to the ejection port arrangement surface of the recording head due to the ink or the like thickened by the wiping operation.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view particularly showing a wiping mechanism in an ink jet printer according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the wiping mechanism shown in FIG.

FIG. 3 is a cross-sectional view showing a wiping mechanism according to a second embodiment of the present invention.

FIG. 4 is a schematic perspective view showing a wiping mechanism according to a conventional example.

[Explanation of symbols]

 Reference Signs List 1 recording head 2 cap case 3 wiping roller 4 lead screw 5 cleaner roller 6 motor 7 waste ink drain 8 inlet

Claims (6)

[Claims] 1. An ink jet recording apparatus which uses a recording head provided with a plurality of ink ejection ports and ejects ink from the recording head to a recording medium to perform recording, wherein the plurality of ink ejection ports of the recording head are arranged. A wiping roller having a length shorter than the length of the area to be wiped, and by wiping the wiping roller, performing a wiping operation on the surface of the recording head on which the plurality of ink ejection ports are provided, and wiping the wiping roller. Wiping means for moving the plurality of ink ejection ports in the arrangement direction; and a surface on which the wiping rollers and the plurality of ink ejection ports are arranged by relatively moving a wiping roller and a recording head of the wiping means. And a moving means for contacting with the ink jet recording apparatus. 2. The ink jet recording apparatus according to claim 1, wherein said wiping means transmits a driving force for rotating said wiping roller via a cleaner roller which rotates in contact with said wiping roller. apparatus. 3. The wiping means includes a lead screw rotatably supporting a wiping roller, a lead screw in which a groove of the wiping roller is engaged with a part of the wiping roller, the lead screw extending in a moving direction of the wiping roller. 3. The ink jet recording apparatus according to claim 1, wherein the wiping roller performs the movement of the wiping roller by an interaction between the groove and a part of the wiping roller when the wiping roller rotates. 4. The wiping unit according to claim 3, wherein the wiping unit has a cap for capping the recording head, and the wiping roller, the lead screw, and the cleaner roller are housed in the cap. Ink jet recording device. 5. The ink jet recording apparatus according to claim 4, wherein a cleaning liquid for immersing the cleaner roller can be introduced into the cap. 6. The recording head according to claim 1, wherein the recording head uses thermal energy to generate bubbles in the ink, and discharges the ink by the pressure of the bubbles. Inkjet recording device.