JP3014270B2 - Ink jet recording device - Google Patents

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 for performing recording by discharging ink from a recording means onto a recording material.

[0002]

2. Description of the Related Art A recording apparatus having functions such as a printer, a copying machine, a facsimile or the like, or a recording apparatus used as an output device of a multifunction machine or a workstation including a computer, a word processor, etc. An image (including characters and symbols) is recorded on a recording material (recording medium) such as an OHP (such as an OHP). The recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a thermal transfer type, a laser beam type, and the like according to a recording method of a recording unit to be used.

In a serial type recording apparatus employing a recording method in which a main scanning is performed in a direction crossing a conveying direction (sub-scanning direction) of the recording material, the recording material is set at a predetermined recording position, and then the recording material is set. An image (including characters and symbols) is recorded by recording means (recording head) mounted on a carriage that moves (main scans) along the line, and after recording for one line is completed, a predetermined amount of paper (Scanning), and thereafter, the operation of recording (main scanning) the image of the next line is repeated, whereby the image is recorded in a desired range of the recording material. On the other hand, in a line type recording apparatus that performs recording only by sub-scanning in which a recording material is transported in the transport direction, the recording material is set at a predetermined recording position, and recording for one line is continuously performed collectively. By feeding a predetermined amount of paper (pitch feed), an image is recorded on the entire recording material.

Among them, the ink jet type (ink jet recording apparatus) performs recording by ejecting ink from a recording means (recording head) to a recording material, so that the recording means can be easily made compact and high definition. Images can be recorded at a high speed, recording can be performed on plain paper without special processing, running costs are low, and the non-impact method reduces noise and uses multicolor inks. This makes it easy to record a color image. Above all, a line-type printing apparatus using a line-type printing means in which a large number of ejection ports are arranged in the paper width direction can further speed up printing.

[0005] In particular, an ink jet type recording means (recording head) for discharging ink by using thermal energy,
Through a semiconductor manufacturing process such as etching, vapor deposition, sputtering, etc., an electrothermal converter, an electrode,
By forming the liquid path wall, the top plate, and the like, it is possible to easily manufacture a device having a high-density liquid path arrangement (discharge port arrangement), and to further reduce the size. Further, by utilizing the advantages of the IC technology and the micromachining technology, it is easy to make the recording means longer and planar (two-dimensional), and it is also easy to make the recording means full multi-layer and high-density mounting. is there.

[0006] In an ink jet recording apparatus which performs recording by discharging ink from a fine discharge port, in order to prevent ink evaporation from the discharge port or protect the discharge port surface when left for a long time or during non-recording. In addition, a cap made of a rubber-like elastic body is pressed against a discharge port surface to seal the discharge port (capping). In addition, in the ink jet recording apparatus, in order to maintain and recover normal ink ejection, a pump connected to the cap is operated in a capping state to generate a negative pressure in the ejection port, thereby causing air bubbles, dust, etc. in the ejection port. A recovery processing capability of sucking out foreign matter together with ink is also performed.

[0007] In an ink jet recording apparatus for color recording for recording with a plurality of different color inks, a plurality of ejection port groups (or a plurality of recording heads) are used corresponding to each color. In the ink jet recording head for color recording, the ejection port groups of the respective colors are arranged close to each other and in the same plane or in an approximate plane.

As the cap for sealing the ejection port of the recording head, a cap having a rib closely contacting the periphery of the ejection port to prevent the ejection port from drying is used. In addition, the cap may be used in connection with a recovery device including a suction pump or the like for filling ink into a liquid passage communicating with each discharge port or sucking out the fixed or thickened ink from the discharge port. . Further, in the ink jet recording apparatus, foreign matters such as paper dust, other dust, and ink droplets may adhere to the ejection port surface or a front plate provided therearound. Then, an operation (wiping operation) of sliding the blade of the rubber-like elastic body against the discharge port surface at a predetermined timing is performed.

[0009]

However, the cap has a substantially rectangular rib, and after the pump is suctioned in a state in which the discharge port is sealed in close contact with the front plate, the cap is simply removed. Therefore, there is a disadvantage that ink remains on the contact surface between the rib of the cap and the front plate. In an ink jet recording apparatus for color recording, when the ejection port surface is wiped (wiped) with the blade while the remaining ink on the front plate remains, the ink remaining on the front plate is pushed into the ejection port, and the ink is discharged. , And wasteful consumption of ink increases due to an increase in the number of preliminary discharges for preventing color mixture, and a space for waste ink increases, resulting in an increase in size of the apparatus body.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems. When the cap is detached from the front plate, the ink remaining on the surface in close contact with the rib is positively determined. In order to prevent the ink remaining in the approach direction of the wiping blade by guiding in the direction of the wiping blade, it is possible to prevent the blade from pushing the mixed color ink into the ejection port (the ink remaining on the contact surface is mixed). This is to reduce the amount of ink for preliminary ejection.

[0011] The ink is guided by changing the shape of the rib of the cap from a simple rectangle to a part of which has a curve or an angle with respect to the rib on the opposing surface. By using the surface tension to guide the ink in a desired direction.

That is, according to the present invention, in an ink jet recording apparatus for performing recording by discharging ink from a recording means to a recording material, a front plate provided substantially on the same plane as a discharge port of the recording means; A cap for sealing the discharge port by being pressed by the front plate, wherein the cap is provided with a rib for tightly sealing the front plate, and the rib is provided when the cap is opened. By adopting a configuration in which at least one side is sequentially separated from the front plate, it is possible to prevent the mixed-color ink from being pushed into the discharge ports when wiping and cleaning the discharge port surface, and thereafter, Preliminary discharge can be reduced to prevent wasteful consumption of ink. In addition, small waste ink processing capacity can be achieved, and running cost can be reduced. And it is possible to reduce the size of the apparatus, there is provided a highly reliable ink jet recording apparatus.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, when the cap is detached, the ink at the contact portion with the front plate is guided in a predetermined direction. When the ink comes off, the ink in the contact portion with the front plate is guided in a predetermined direction, and the wiping blade in contact with the front plate enters from a direction where no ink remains, and the rib of the cap is attached to the front plate. With a configuration in which the contact width of the cap is sequentially changed in one direction, or a configuration in which the rib of the cap is substantially rectangular and is configured to be opened from a corner portion when the cap is detached, more efficiently, The above object is achieved.

[0014]

Since the contact line between the front plate and the rib of the cap separates sequentially instead of once, the ink is guided by utilizing the movement of the liquid in the direction with a small gap due to surface tension. Thus, the remaining ink is eliminated in the approach direction of the wiping blade. This prevents the ink from being pushed into the ejection port by the blade during wiping.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the same reference numerals indicate the same or corresponding parts. FIG. 1 is a schematic perspective view showing one embodiment of an ink jet recording apparatus to which the present invention is applied. In FIG. 1, reference numeral 1 denotes a replaceable cartridge type recording unit (recording head) having an integrated ink tank, and 2 denotes a carriage on which the recording head 1 is mounted and which reciprocates in the directions of arrows A and B in the figure. It is. The recording head 1
Is electrically connected to a control circuit of the apparatus main body via a flexible cable 7 described later.

Reference numeral 3 denotes a hook for attaching the recording head 1 to the carriage 2, and reference numeral 4 denotes a lever for operating the hook 3. The carriage 2 is formed with a concave portion 5 into which a convex portion 24 described later enters. Reference numeral 6 denotes a support plate for supporting an electrical connection to the recording head 1, and reference numeral 7 denotes a flexible cable for connecting the electrical connection to the control unit of the apparatus main body. Reference numeral 8 denotes a guide rail which is inserted into the carriage 2 and guides and supports the carriage 2 in directions indicated by arrows A and B. Reference numeral 9 denotes a timing belt which is connected to the carriage 2 and transmits power for moving the carriage 2 in the directions of arrows A and B. The timing belt 9 includes pulleys 10A, 10A,
It is stretched over B. A driving force is transmitted to one pulley 10B from the carriage motor 11 via a transmission mechanism such as a gear.

In FIG. 1, reference numeral 12 denotes a platen roller, and reference numeral 13 denotes a transport motor for driving the platen roller. The platen roller 12 regulates the recording surface of a recording material (recording medium) such as paper, and conveys (paper feeds) the recording material during recording or the like. 14 is a paper pan for guiding the recording material to the recording device,
Reference numeral 15 denotes a feed roller for pressing the recording material toward the transport roller 12. This feed roller 15 is
The recording medium is provided in the conveyance path of the recording material, and is for applying a conveying force to the recording material by pressing the recording material against the conveyance roller 12.

Reference numeral 16 denotes a discharge roller for discharging the recording material toward a discharge port (not shown), and 17 denotes a discharge roller 1.
6 is a spur provided correspondingly. The discharge roller 1
Reference numeral 6 is disposed downstream of the recording position in the recording material transport direction. In addition, the spur 17 is used for discharging the recording material to the discharge roller 1.
6 to apply the conveying force of the paper discharge roller 16 to the recording material. Reference numeral 18 denotes a platen provided at a position facing the ink discharge port of the recording head 1. The platen 18 is urged toward the paper pan front portion 19 by an elastic member (not shown), and presses the recording material therebetween. It is arranged to hold.

In the ink jet recording apparatus shown in FIG. 1, an ink jet recording head which performs recording while flying ink droplets toward a recording material is employed as a recording means (recording head) 1. Therefore, it is necessary to set the distance between the ejection port of the recording head 1 and the recording surface of the recording material to be small, and to strictly control the interval to avoid contact between the recording material and the ejection port. The paper pan front surface portion 19 is useful for regulating the position of the recording material and appropriately managing the distance from the ejection port.

In FIG. 1, reference numeral 20 denotes a feed roller 15, a spur 17, and a platen 18 when a recording material is attached or detached.
Release lever to release the bias of each of
Reference numeral 21 denotes a sensor for detecting the position of the carriage 2.
The sensor 21 detects the position of the carriage 2 by passing through a protrusion (not shown) provided on the carriage 2.

Reference numeral 22 denotes a cap facing the ejection port surface of the recording head 1 (the surface on which the ink ejection ports are formed) at the home position of the carriage 2. This cap 2
Numeral 2 is formed of a rubber-like elastic material, and is supported so as to be capable of coming into contact with / separating from the ejection port surface of the recording head 1. At this time, it is used to contact the discharge port surface to seal the discharge port. The ejection recovery processing includes discharging the ink from all the ejection ports by driving the energy generating element provided inside the ejection port and used for ink ejection by bringing the cap 22 into contact with the ejection port surface. (Preliminary discharge) or ink that is not suitable for recording due to bubbles, dust, thickening, etc. by forcibly discharging ink by applying a suction force to the discharge port while the discharge port surface is covered by the cap 22. This is a process for removing a discharge failure factor such as

In FIG. 1, reference numeral 23 denotes a pump used for a discharge recovery process. The pump 23 applies a suction force for forcibly discharging the ink, and is used for sucking the ink received by the cap 22 in the discharge recovery process by the forced discharge and the discharge recovery process by the preliminary discharge. On the outer shape of the pump 23, a convex portion 24 that enters the concave portion 5 of the carriage 2 is formed. 25
Is a waste ink tank for storing waste ink sucked by the pump 23;
And a tube that communicates with the waste ink tank 25.

Reference numeral 27 denotes a wiping blade for wiping off foreign substances on the discharge port surface of the recording head 1 for cleaning. The blade 27 is formed of an elastic material such as rubber, and protrudes toward the recording head 1 to advance the discharge port surface during wiping (wiping and cleaning) of the recording head 1 in the course of movement. The head 1 is movably supported at a retracted position that does not come into contact with the discharge port surface. The operation of the pump 23 and the driving of the recovery mechanism such as the movement (forward and backward) of the cap 22 and the blade 27 are performed by respective or common motors.

The recording means (recording head) 1 is an ink jet recording means for discharging ink using thermal energy, and is provided with an electrothermal converter for generating thermal energy. Further, the recording head 1 includes:
The recording is performed by discharging ink from the discharge ports by utilizing a pressure change generated by growth and shrinkage of bubbles caused by film boiling caused by the heat energy applied by the electrothermal transducer.

FIG. 2 is a partial perspective view schematically showing the structure of the ink ejection section of the recording head 1. In FIG. 2, a predetermined gap (for example, about 0.5
A plurality of discharge ports 82 are formed at a predetermined pitch on the discharge port surface 81 facing at an interval of about 2.0 mm), and each of the liquid paths 84 communicating the common liquid chamber 83 and each discharge port 82 is formed. An electrothermal converter (heat generating resistor or the like) 85 for generating energy for ink ejection is provided along the wall surface.
In the present embodiment, the recording head 1 is mounted on the carriage 2 in such a manner that the discharge ports 82 are arranged in a direction crossing the scanning direction of the carriage 2. Thus,
A recording means for driving (energizing) the corresponding electrothermal transducer 85 based on an image signal or a discharge signal to cause the ink in the liquid path 84 to boil, and to discharge the ink from the discharge port 82 by the pressure generated at that time. 1 is configured.

FIG. 3 is a schematic perspective view showing the capping mechanism of the first embodiment of the ink jet recording apparatus to which the present invention is applied. In FIG. 3, the cap 22 is formed of a rubber-like elastic material such as rubber, and is preferably formed of, for example, chlorinated butyl rubber having a low gas permeability. The cap 22 is integrally formed with a rib 31 for tightly adhering to a front plate of the recording head 1 to be described later and sealing the discharge port 82. The ribs 31 are connected to the ejection openings 8 of the recording head 1.
2 and a vertical rib 31A formed in parallel with the arrangement direction of the discharge ports 82, and horizontal ribs 31B and 31 formed up and down in a direction perpendicular to the arrangement direction of the discharge ports 82.
B, and a chevron-shaped rib 31C which is formed in an inverted letter shape so as to face the vertical rib 31A and move away from the center.

The area inside the rib 31 is deepened toward the center in the shape of a pyramid, and a suction hole 32 for suction is formed near the center. The suction hole 32 extends to the rear of the cap 22 and communicates with a suction tube mounting part (not shown). 33 is a cap holder. The cap holder 33 has a substantially box shape having a rectangular opening for holding the outer shape of the cap 22, and holder shafts 34, 34 are erected on upper and lower surfaces thereof. Further, the chevron rib 31C of the cap 22
A spring hanging shaft 35 is provided upright in the same direction.

In FIG. 3, the cap holder 33
A cap lever 36 is provided on the rear side. At opposing upper and lower positions of the front surface of the cap lever 36,
Arm portions 37, 37 for rotatably supporting the holder shafts 34, 34 of the cap holder 33 are formed.
A guide arm 38 is integrally formed on the surface of the cap lever 36 opposite to the cap 22. Rack teeth 39 are formed integrally with a part of the upper side of the guide arm 38. The guide arm 38 has an elongated guide hole 4 for sliding the guide arm 38 in parallel.
0 and 40 are formed on a straight line.

Further, a lever spring hanging shaft 41 is provided upright at a position of the cap lever 36 at the same height as the spring hanging shaft 35 of the cap holder 33. A cap holder spring 42 is stretched between a spring hook shaft 35 of the cap holder 33 and a lever spring hook shaft 41 of the cap lever 36. The spring 42 generates tension for rotating the cap holder 33 in one direction. The cap lever 36 is provided with a guide hole (a long hole) 40 in a guide shaft 43 erected on a frame (not shown).
Are fitted to the recording head 1 so as to be able to move forward and backward.

In FIG. 3, a gear 45 is fixed to the motor shaft of the cap motor 44, and the gear 45 meshes with the rack teeth 39 of the cap lever 36. As the cap motor 44, it is preferable to use a motor such as a pulse motor that rotates forward and backward by giving a predetermined pulse.

FIG. 4 is a schematic plan view of the recovery device of the first embodiment of the ink jet recording apparatus to which the present invention is applied.
In FIG. 4, a wiping mechanism for wiping and cleaning the discharge port surface (front plate) of the recording head 1 is provided alongside the capping mechanism described in FIG. The wiping mechanism includes a blade 27 made of a rubber-like elastic material and a blade holder 46 for holding the blade 27.
The blade holder 46 is attached to a frame of the recording apparatus. In addition, the blade 27
Is held at a position having a predetermined amount of overlap with the front plate 47 of the recording head 1. A suction tube 48 is connected to the suction port 32 of the cap 22, and the other end of the suction tube 48 is connected to the suction pump 23 (FIG. 1).

FIG. 5 is a schematic external perspective view of the recording head 1. 4 and 5, on the discharge port surface 81 of the recording head 1, a discharge port group for recording in yellow, a discharge port group for recording in magenta, a discharge port group for recording in cyan, and black. An ejection port group for ejecting four color inks is formed in the order of the ejection port group to be recorded. The front plate 47 is attached so as to surround the discharge port surface 81. In this embodiment, the front plate 47 has a flat seal portion slightly receded from the surface of the ejection port surface 81, and is attached to the ink tank portion 49 of the recording head 1.

The ink tank 49 of the recording head 1
Form a container by holding the ink inside and attaching the front plate 47. An ink absorber 50 is attached to a side surface of the recording head 1 (ink tank portion 49) on the rear side in the direction of arrow A.

FIG. 6 is a schematic plan view showing the operation of the first embodiment of the ink jet recording apparatus described above in a partly broken manner and showing the operation step by step. In FIG. 6, for simplicity,
Only the recording head 1, the cap 22, and the suction tube 48 are shown. FIG. 6A shows a state in which the cap 22 is pressed and closely attached to the front plate 47 of the recording head 1. 1 to 6, when the cap motor 44 is rotated clockwise (direction of arrow C), the rack teeth 39 (cap lever 36) meshing with the pinion 45 move in the forward direction (arrow D), and the cap 22 is rotated. The vertical rib 31 </ b> A of the rib 31 first contacts the front plate 47 of the recording head 1.

When the cap lever 36 advances further,
The cap holder 33 rotates in the direction of the arrow E around the holder shafts 34, 34 against the spring force of the cap holder spring 42, and the front plate 47 and the cap 22 are finally parallel while the ribs 31A of the cap 22, 3
All of 1B and 31C are in close contact with the front plate 47, and the sealing (capping) of the recording head 1 is completed, and the state shown in FIG.

Next, the cap 22 is moved by the suction pump 23.
When the inside is set to a negative pressure, the ink is sucked out from the ejection port 82, and the cap 22 is filled with the ink as shown in FIG. At this time, the four colors of yellow, magenta, cyan, and black are mixed to form a mixed color ink. Thereafter, the cap motor 44 is slightly rotated in the direction opposite to the direction of arrow A (counterclockwise) while being sucked by the pump 23, and stopped.

At this time, since the cap holder 33 is rotated by the spring force of the cap holder spring 42, as shown in FIG. 6C, the cap 22 on the side of the cap holder spring 42, that is, the chevron of the chevron rib 31C. The part will be slightly open. Then, since the air flows into the cap 22 from the opened portion, the ink in the cap 22 is sucked into the suction pump 23 and the discharge port 82
Does not come out of the ink. After a predetermined time has passed, after all the ink in the cap 22 has been sucked, the cap motor 44 is again rotated counterclockwise to
6 is retracted.

Vertical rib 31A, horizontal rib 31 of cap 22
The mixed color ink is held by the surface tension on the contact surface (front plate 47) with B, 31B and the chevron rib 31C. In the present embodiment, the vertical ribs 31A, the horizontal ribs 31B, 31B, and the chevron ribs 31C are pressed and slightly crushed in order to secure the sealing property during capping, so only the chevron portions of the chevron ribs 31C are exposed to the atmosphere. It is possible to communicate. FIG. 7 is a principle view schematically showing a state in which the cap 22 of the first embodiment shown in FIGS.

When the cap 22 is gradually retracted by the counterclockwise rotation of the cap motor 44, the pressed rib 31 is released from being crushed, and then the front plate 4
7 is performed. At this time, since the chevron rib 31C of the cap 22 has a chevron shape, it is gradually separated from the front plate 47 from the vertex of the chevron. Then, the ink on the contact surface is guided to the side where the gap is small as shown in FIG. 7, so that the ink moves in the direction of arrow F in FIG. Cap motor 44
When the is further rotated, the cap 22 is
7, the detachment of the cap 22 is completed.

FIG. 8 shows the cap 2 according to the first embodiment.
2A and 2B are schematic front views illustrating a front surface (close contact surface) of the recording head 1 and FIG. 2A, wherein FIG. Regarding the ink remaining on the contact surface, the ink in the mountain-shaped portion of the angled rib 31C is
B, 31B, the ink on the contact surfaces of the horizontal ribs 31B, 31B and the vertical rib 31A remains as it is,
As shown in FIG. 8B, the ink remains on the front plate 47 in a U-shape, and a side where no ink remains can be secured. Next, the front plate 47 is wiped and cleaned by the wiping blade 27 in the direction of arrow G (the recording head 1 moves in the direction opposite to the direction of arrow G). By this wiping cleaning (wiping), the remaining ink on the front plate 47 is absorbed by the ink absorber 50, and the front plate 47 and the discharge port surface 81 are also cleaned.

According to the embodiment described above, the shape of the rib (adhesion portion) 31 of the cap 22 is selected, and the cap 22 is detached from the front plate 47 in order to separate the cap 22 after sucking the ink. It is possible to control that the ink remaining in the close contact portion when opening is retracted from the direction of entry of the wiping blade 27, thereby preventing the mixed ink from being pushed into the ejection openings 82 when wiping with the wiping blade 27. This makes it possible to reduce the amount of subsequent preliminary ejection, thereby preventing wasteful consumption of ink. Further, the processing capability of the waste ink can be reduced, the running cost is inexpensive, the size can be reduced, and a highly reliable ink jet recording apparatus can be obtained.

FIGS. 9A and 9B are schematic diagrams showing the shape of the cap 22 and the state of remaining ink on the front plate of the recording head 1 in the second embodiment of the ink jet recording apparatus to which this embodiment is applied. It is a front view. In FIG. 9A, the ribs 31 of the cap 22 are vertical ribs 31.
A, the lower lateral rib 31B and the arcuate rib 31D. The ink remaining on the front plate 47 after ink suction is performed using the cap 22 of the present embodiment has an inverted L-shape as shown in FIG. 9B, and no ink remains on the upper and left sides. It will be.

According to the second embodiment shown in FIG.
And the front plate 47 is moved in the direction of arrow G by the wiping blade 27 (when the recording head 1
In the case of wiping cleaning, there is no ink at the upper part, so that ink does not flow down and the reliability of color mixing prevention is improved. Also, by using a wiping blade for wiping and cleaning in the direction of the arrow H (vertical direction), it is possible to prevent the ink from being pushed into the ejection openings 82 and to obtain the effect of preventing color mixing. That is, according to the second embodiment shown in FIG. 9, the same effect as that of the first embodiment shown in FIG. 8 can be obtained. In addition, the reliability of preventing color mixing is further improved, and the degree of freedom in the wiping direction by the blade is increased. Can be improved.

FIGS. 10A and 10B are schematic diagrams showing the shape of the cap 22 and the state of remaining ink on the front plate of the recording head 1 in a third embodiment of the ink jet recording apparatus to which this embodiment is applied. It is a front view. FIG.
In FIG. 0A, the ribs 31 of the cap 22 are formed by horizontal ribs 31B on the lower side and arcuate ribs 31E on the left and right sides having an intersection 51 above. The cap 22 is detached from the direction of the intersection 51. The detaching operation of the cap 22 in this case is performed according to the same principle as in the case of FIGS.

The remaining ink on the front plate 47 after the suction of the ink using the cap 22 of this embodiment is only one lower side as shown in FIG. 10B. Therefore, according to the third embodiment shown in FIG. 10, in addition to obtaining the same effects as those of the first and second embodiments described above, since the ink remains only on one side, the blade 27 can freely move in the entering direction. The degree of freedom can be further increased, and the degree of freedom of the size and position of the ink absorber 50 can be increased.

FIGS. 11A and 11B are schematic diagrams showing the shape of the cap 22 and the state of remaining ink on the front plate of the recording head 1 in the fourth embodiment of the ink jet recording apparatus to which this embodiment is applied. It is a front view. The rib 31 of the cap 22 is, as shown in FIG.
A horizontal horizontal rib 31B is formed on the lower side, and arcuate ribs 31E on the left and right sides extending from both ends to an intersection 51 on the upper side.
31E is formed. Each of the left and right arc-shaped ribs 31E is thin (Δw) at the upper portion and has a larger width (ΔW) toward the lower portion.

The detachment of the cap 22 in this embodiment is performed as follows.
As in the case of FIG. 10, the process is performed from the direction of the upper intersection point 51. The detaching operation of the cap 22 in this case is also described in FIGS.
It can be performed on the same principle as in the case of This cap 2
By the separation of 2, the ink in the contact portion is guided to the lower side horizontal rib 31B side. In that case, the ink at the contact portion is
Is left at the corner between the side surface of the front plate 47 and the front plate 47 due to surface tension, so that the remaining amount of ink is determined in proportion to the length of the rib 31. In the configuration as shown in FIG.
When the ink is held in the gap when E and 31E are detached from the front plate 47, the ink amount increases as the ink is guided downward.

Therefore, according to the embodiment of FIG. 11, since the width of each of the left and right arc-shaped ribs 31E is increased, the capacity for holding and guiding the ink can be increased, and the surface tension is correspondingly increased. Can reliably guide the ink, and the reliability can be improved.
That is, according to the fourth embodiment shown in FIG. 11, the same effects as those of the above-described embodiments can be obtained. In addition, the capacity of holding and guiding the ink is increased to more reliably guide the ink by the surface tension. Thus, an ink jet recording apparatus that can further enhance the effect of preventing color mixing when wiping and cleaning with a blade can be obtained.

FIG. 12 is a view showing a state in which the cap 22 is detached from the recording head 1 in the fifth embodiment of the ink jet recording apparatus to which the present embodiment is applied, and FIG. 12 (a) is a schematic rear view of the cap 22. FIG. 5B is a side view as viewed from the direction of arrow K in FIG. In FIG. 12, even when a substantially rectangular cap 22 having a conventional shape is used,
By opening the corner, the ink can be guided in a desired direction. In this case, the cap 22
Is bent from the front plate 47 so as to bend at the diagonal J, so that the remaining ink on the front plate 47 can be formed into an L-shape as in the second embodiment of FIG.

That is, according to the fifth embodiment of FIG. 12, as in the case of the second embodiment of FIG. 9, the ink mixing due to the ink being pushed into the discharge port 82 when the wiping blade 27 wipes and cleans is prevented. can do.
Further, according to the present embodiment, the cap 22 can be used as it is in the conventional type, and the concern of an increase in the width of the cap 22 in the width direction can be eliminated.

In each of the embodiments described above, the serial recording system in which the recording means (recording head) is moved in the main scanning direction has been described as an example. Also in the case of a line recording method in which recording is performed only by sub-scanning using a line recording unit having a length covering the portion,
It can be applied similarly and can achieve the same effect. In addition, the present invention provides a color printing apparatus using a plurality of printing means for printing in different colors, a single-color printing apparatus for printing with one printing means, or a plurality of printing means for printing in the same color at different densities. Gradation recording device to be used,
Furthermore, in the case of a recording device combining these,
It can be applied similarly and can achieve the same effect.

Further, the present invention relates to the case where a replaceable head cartridge in which a recording head and an ink tank are integrated is used, or the case where the recording head and the ink tank are separated and connected between them by an ink supply tube or the like. For example, the present invention can be applied to any arrangement of the recording head and the ink tank, and the same effect can be obtained.

The present invention can be applied to an ink jet recording apparatus using a recording means (recording head) using an electromechanical transducer such as a piezo element. This provides an excellent effect in an ink jet recording apparatus using a recording means of a method of ejecting ink. 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.
Preferably, this is done using the basic principles disclosed in US Pat. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, liquid (ink)
By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding nucleate boiling to an electrothermal transducer arranged corresponding to the sheet or liquid path in which Then, heat energy is generated in the electrothermal transducer, and the film is boiled on the heat acting surface of the recording means (recording head). As a result, air bubbles in the liquid (ink) can be formed in one-to-one correspondence with the driving signal. It is effective.

By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. 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, US Pat.
Those described in 463359 and 4345262 are suitable. In addition, US Pat. No. 4,431,131 of the invention relating to the rate of temperature rise of the heat acting surface.
If the conditions described in the specification of JP-A No. 24 are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of the discharge port, the liquid path, and the electrothermal converter (linear liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,558,333 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. 459600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication (Kokai) No. 123670/1984 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 pressure waves of thermal energy. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, the recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, as described above, 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 material (recording medium) on which a recording apparatus can record. . As such a recording head,
Either a configuration that satisfies the length by combining a plurality of recording heads, or a configuration as a single recording head that is integrally formed may be used. In addition, even in the case of the serial type as described above, the recording head fixed to the apparatus main body,
Alternatively, a replaceable chip-type recording head that can be electrically connected to the apparatus main body or supplied with ink from the apparatus main body by being attached to the apparatus main body, or an ink tank is provided integrally with the recording head itself The present invention is also effective when a cartridge type recording head is used.

Further, it is preferable to add recovery means or preliminary auxiliary means for the recording head provided as a configuration of the recording apparatus to the present invention since the effects of the present invention can be further stabilized. Specifically, in addition to the capping means, the cleaning means, and the suction recovery means as described above, a pressurized recovery means, an electrothermal converter, or another heating means for the recording head. It is also effective to perform stable printing by performing a preliminary heating mode using a device or a combination thereof and a preliminary ejection mode in which ejection is performed separately from printing.

As described above, the type and number of print heads to be mounted may be, for example, one provided for only one color ink, or a plurality of print heads having different print colors and densities. A plurality of inks may be provided in correspondence with the above ink. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, and may be any of a configuration in which the recording head is integrally formed or a combination of a plurality of recording heads. The present invention is extremely effective for an apparatus provided with at least one of color colors or 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, or an ink jet ink is used. In general, in the method, the temperature of the ink itself is adjusted 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. What is necessary is just to be liquid. in addition,
Whether 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 use ink that solidifies in a standing state to prevent evaporation of the ink In any case, the ink is liquefied by the application of the heat energy according to the recording signal, and the liquid ink is ejected,
The present invention is also applicable to a case where an ink having a property of being liquefied for the first time by thermal energy, such as one that starts to solidify when it reaches a recording medium, is used.

The ink in such a case is disclosed in
As described in JP-A-56847 or JP-A-60-71260, a form in which the liquid sheet or the solid sheet is opposed to the electrothermal converter while being held as a liquid or solid substance in the concave portion or through hole of the porous sheet. It may be. 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 according to the present invention is not only used as an image output terminal of an information processing apparatus such as a computer, but also a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. And the like.

[0063]

As is apparent from the above description, according to the first aspect of the present invention, in an ink jet recording apparatus for performing recording by discharging ink from a recording means to a recording material, substantially the same as the discharge port of the recording means. A front plate provided on a flat surface, and a cap pressed against the front plate to seal the discharge port, wherein the cap is provided with a rib for tightly sealing the front plate. Since the ribs are formed so that at least one side thereof is sequentially separated from the front plate when the cap is opened, the ribs are pushed into the discharge ports when the discharge port surfaces are wiped and cleaned. Can be prevented,
There is provided an ink jet recording apparatus capable of preventing unnecessary waste of ink by reducing the amount of subsequent preliminary ejection and requiring only a small waste ink processing capacity.

According to the second to fifth aspects of the present invention, in addition to the configuration of the first aspect, when the cap is detached, the ink at the contact portion with the front plate is guided in a predetermined direction, When the cap is detached, the ink in the contact portion with the front plate is guided in a predetermined direction, and the wiping blade in contact with the front plate enters from a direction in which no ink remains, and the rib of the cap is A configuration in which the contact width with the front plate is sequentially changed in one direction, or a rib of the cap,
It is substantially rectangular, and it is configured to open from the corner when the cap is detached, so it is possible to more efficiently prevent the mixed color ink from being pushed into the discharge port when wiping and cleaning the discharge port surface, There is provided an ink jet recording apparatus capable of preventing unnecessary waste of ink by reducing the amount of subsequent preliminary ejection and requiring only a small waste ink processing capacity.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view showing a configuration of an embodiment of an ink jet recording apparatus to which the present invention is applied.

FIG. 2 is a partial perspective view schematically illustrating a structure of an ink ejection unit of a recording unit in FIG.

FIG. 3 is a schematic perspective view showing a capping mechanism of the first embodiment of the ink jet recording apparatus to which the present invention is applied.

FIG. 4 is a schematic plan view showing a recording unit and a wiping mechanism in addition to the capping mechanism of FIG.

FIG. 5 is a schematic external perspective view of a recording unit in FIG. 4;

FIG. 6 is a partially broken plan view schematically showing a detaching operation of the capping mechanism of FIG. 3;

FIG. 7 is a schematic view showing the principle of the detaching operation of the capping mechanism of the ink jet recording apparatus according to the present invention.

FIG. 8 is a schematic front view showing a contact surface of a cap and a recording unit according to the first embodiment of the present invention.

FIG. 9 is a schematic front view showing a contact surface of a cap and a recording unit according to a second embodiment of the present invention.

FIG. 10 is a schematic front view showing a contact surface of a cap and a recording unit according to a third embodiment of the present invention.

FIG. 11 is a schematic front view showing a contact surface of a cap and a recording unit according to a fourth embodiment of the present invention.

FIG. 12 is a rear view and a side view schematically showing a cap according to a fifth embodiment of the present invention and a state when the cap is removed.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 recording means (recording head) 2 carriage 7 flexible cable 8 guide rail 9 timing belt 11 carriage motor 12 transport roller 13 transport motor 15 feed roller 16 discharge roller 18 platen 22 cap 23 pump 25 waste ink tank 27 wiping blade 31 rib 32 Suction port 33 Cap holder 36 Cap lever 42 Cap holder spring 44 Cap motor 46 Blade holder 47 Front plate 48 Suction tube 49 Ink tank unit 50 Ink absorber 51 Intersection 81 Discharge port face 82 Discharge port 84 Liquid path 85 Electrothermal converter

Claims (7)

(57) [Claims] 1. An ink jet recording apparatus which performs recording by discharging ink from a recording means to a recording material, a front plate provided substantially on the same plane as an ejection port of the recording means, and a front plate pressed by the front plate. A cap for sealing the discharge port, wherein the cap is provided with a rib for tightly sealing the front plate, and the rib has at least one side with respect to the front plate when the cap is opened. Are formed so as to be sequentially separated from each other. 2. The ink jet recording apparatus according to claim 1, wherein when the cap is detached, ink in a contact portion with the front plate is guided in a predetermined direction. 3. The ink in a contact portion with the front plate is guided in a predetermined direction when the cap is detached, and the wiping blade in contact with the front plate enters from a direction in which no ink remains. The ink jet recording apparatus according to claim 1, wherein 4. The ink jet recording apparatus according to claim 1, wherein the rib of the cap has a shape in which a contact width with the front plate changes sequentially in one direction. 5. The ink jet recording apparatus according to claim 1, wherein the rib of the cap has a substantially rectangular shape and is opened from a corner when the cap is detached. 6. An ink jet recording apparatus according to claim 1, wherein said recording means is an ink jet recording means provided with an electrothermal converter for generating thermal energy used for discharging ink. 7. An ink jet recording apparatus according to claim 6, wherein said recording means discharges the ink from a discharge port using film boiling generated in the ink by thermal energy generated by the electrothermal transducer. .