JP4040386B2 - Inkjet recording device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ink jet recording apparatus that performs recording by discharging ink from a nozzle of an ink jet recording head to a recording medium.
[0002]
[Prior art]
Recording devices having functions such as printers, copiers, facsimiles, etc., or composite electronic devices including computers and word processors, and recording devices used as output devices for workstations, are based on image information such as paper and plastic thin plates. It has a configuration for recording an image on a recording material (recording medium). Such a recording apparatus can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type, and the like according to a recording method.
[0003]
In a serial type recording apparatus that employs a serial scanning method in which main scanning is performed in a direction crossing the recording material conveyance direction (sub-scanning direction), an image is recorded by recording means mounted on a carriage that moves along the recording material. Recording is performed on the entire recording material by repeating the operation of recording and feeding a predetermined amount of paper (pitch conveyance) after recording for one line is completed. On the other hand, in a line type recording apparatus that records only by sub-scanning in the conveyance direction of the recording material, the recording material is set at a predetermined recording position, and after recording for one line at a time, a predetermined amount The recording is performed on the entire recording material by repeating the operation of performing the paper feeding (pitch feeding) and the recording of the next line all at once.
[0004]
Among the above recording apparatuses, an ink jet recording apparatus (ink jet recording apparatus) using a serial scanning method performs recording by ejecting ink from a recording means (recording head) to a recording material. Is easy to make compact, can record high-definition images at high speed, can be recorded on plain paper without any special treatment, has low running cost, and is non-impact, so there is little noise In addition, there is an advantage that it is easy to record a color image using multicolor inks.
[0005]
In particular, an ink jet recording means (recording head) that discharges ink using thermal energy is an electrothermal transducer, electrode, liquid formed on a substrate through a semiconductor manufacturing process such as etching, vapor deposition, and sputtering. By forming a road wall, a top plate, etc., a product having a high-density liquid channel arrangement (discharge port arrangement) can be easily manufactured, and further downsizing can be achieved.
[0006]
In recent years, the requirements for the material of the recording material have also been diversified. In addition to the normal recording material such as paper and resin thin plate (OHP, etc.), thin paper and processed paper (paper with punch holes for filing, perforated paper, There is a growing demand for recording on paper having an arbitrary shape.
[0007]
In the above ink jet recording apparatus, in order to obtain a clear and high quality recording result, it is very important to keep the distance between the recording material and the recording head constant and stable. Therefore, in order to improve the smoothness of the recording material, the arrangement of the roller for conveying the recording material, the arrangement of the pressing member for the recording material, the arrangement of the guide member for guiding the end of the recording material, etc. Various devices have been devised in the recording material transport mechanism.
[0008]
[Problems to be solved by the invention]
However, the above prior art has a limit in maintaining the smoothness of the recording material. In particular, the behavior of the recording material becomes unstable at the leading edge and the trailing edge of the recording material, and the recording material may come into contact with the recording head. In particular, this phenomenon becomes prominent when the recording material is curled, and not only the recording material is broken or torn, but in the worst case, the recording head may be destroyed. .
[0009]
SUMMARY An advantage of some aspects of the invention is that it provides an ink jet recording apparatus that can prevent a recording head from being damaged by a recording medium.
[0010]
[Means for Solving the Problems]
To achieve the above object, an ink jet recording apparatus of the present invention, the recording and the heater board in which the nozzles are configured to eject ink, and a flexible circuit board for transmitting electrical signals to the heater board, the printhead having a In an ink jet recording apparatus for recording on a medium, a carriage that detachably mounts the recording head and reciprocally scans the recording medium, and a carriage that guides the recording head when the recording head is mounted on the carriage A cover, and a head protection plate that is molded integrally with the carriage cover and elastically deforms by contacting the recording head when the recording head is mounted on the carriage, and is disposed at a position facing the recording head. the distance between the head protection plate with the recording medium that is, the said recording medium flexible circuit Smaller than the distance between the plates, wherein the greater than the distance between the heater boat with the recording medium.
[0011]
According to the ink jet recording apparatus of the present invention, when the carriage scans, if there is a curled or bent portion (edge portion) of the recording medium in front of the scanning direction, the edge of the recording medium Since the portion first contacts the head protection plate of the carriage, it does not contact the end portion of the recording head. Therefore, it is possible to prevent the recording head from coming into contact with the recording medium and being damaged.
[0016]
Further, by adopting a configuration in which an inclined surface or a curved surface is formed at the end of the head protection plate on the flexible circuit board side, it is possible to prevent the recording medium from being caught by the end. Furthermore, it is possible to prevent as well as alleviate the impact when the recording medium is brought into contact with the end portion of the head protecting plate, the end portion of the head protecting plate or beating the recording medium.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
[0018]
(First embodiment)
FIG. 1 is a perspective view showing the overall configuration of the recording apparatus according to the first embodiment of the present invention, and FIG. 2 is a side sectional view of the recording apparatus.
[0019]
A recording apparatus 1 having an automatic feeding device includes a paper feeding unit 2, a paper feeding unit 3, a paper discharging unit 4, a carriage unit 5, and a cleaning unit 6. Below, these outlines are divided into items and described sequentially.
[0020]
(A) Paper Feed Unit As shown in FIGS. 1 and 2, the paper feed unit 2 is based on a pressure plate 21 on which recording materials (not shown) are stacked and a feed rotating body 22 that feeds the recording materials. 20 is attached. A movable side guide 23 is movably provided on the pressure plate 21, and the movable side guide 23 regulates the stacking position of recording materials. The pressure plate 21 is rotatable about an axis coupled to the base 20, and is urged to the feeding rotating body 22 by a pressure plate spring 24.
[0021]
(B) Paper Feed Unit The paper feed unit 3 includes a transport roller 36 that transports the recording material, and a pinch roller 37 that is in contact with and driven by the transport roller 36. The transport roller 36 and the pinch roller 37 constitute a roller pair. The pinch roller 37 is held by a pinch roller guide 30 and is urged by a pinch roller spring 31 so that the pinch roller 37 is pressed against the transport roller 36, thereby generating a transport force of the recording material. .
[0022]
Further, a platen 34 for guiding the recording material is disposed at the entrance of the paper feeding unit 3 to which the recording material is conveyed. The pinch roller guide 30 is provided with a PE sensor lever 35 that is displaced when the leading and trailing ends of the recording material pass. A head comprising an ink jet recording head that forms an image based on image information sent from the electric substrate 9 (FIG. 2) that also functions as a control unit of the recording apparatus main body, and an ink tank that stores ink to be supplied thereto. The cartridge 7 is disposed on the downstream side of the conveyance roller 36 in the conveyance direction of the recording material.
[0023]
According to the above configuration, the recording material sent to the paper feeding unit 3 is guided by the platen 34 and the pinch roller guide 30 and sent to the roller pair composed of the conveying roller 36 and the pinch roller 37. At this time, the PE sensor lever 35 is pushed and displaced by the leading end of the recording material that has been conveyed, and the PE sensor 32 detects the displacement to obtain the recording position of the recording material. Further, the recording material is conveyed on the platen 34 by rotating the roller pairs 36 and 37 by an LF motor (not shown).
[0024]
In the head cartridge 7 of this embodiment, the ink tank can be replaced with the ink jet recording head. The head cartridge 7 can apply heat to the ink in the nozzles of the recording head by a heater or the like. The ink boiles due to the heat, and the ink is ejected from the nozzles of the recording head due to the pressure change caused by the growth or contraction of the bubbles due to the film boiling, so that an image is formed on the recording material. ing.
[0025]
(C) Carriage part The carriage part 5 has a carriage 50 to which the head cartridge 7 is detachably attached. The carriage 50 holds a guide shaft 81 that reciprocally scans the carriage 50 in a direction perpendicular to the conveyance direction of the recording material, and holds the upper rear end of the carriage 50 so that a gap between the head cartridge 7 and the recording material is constant. It is supported by a guide rail 82 that is maintained at the same time. These guide shafts 81 and guide rails 82 are attached to the chassis 8. Further, the chassis 8 includes a restriction portion 8a for restricting a range in which the carriage 50 moves in the left direction in FIG.
[0026]
The carriage 50 is driven via a timing belt 83 by a carriage motor 80 attached to the chassis 8. The timing belt 83 is stretched and supported by an idle pulley 84. Further, the carriage 50 is provided with a flexible cable 56 for transmitting a recording signal from the electric board 9 to the head cartridge 7. The linear encoder 101 that detects the position of the carriage 50 in the scanning direction is mounted on the carriage 50. The linear encoder 101 can detect the position of the carriage 50 by reading the number of lines formed on the linear scale 102 attached to the chassis 8. A signal relating to the position of the carriage 50 detected by the linear encoder 101 is transmitted to the electric board 9 via the flexible cable 56 and processed.
[0027]
In the above configuration, when an image is formed on the recording material, the roller pairs 36 and 37 convey the recording material to the row position (position in the conveyance direction of the recording material) where the image is recorded, and the carriage motor 80 By the feedback control using the linear encoder 101, the carriage 50 is moved to a row position (a position perpendicular to the conveyance direction of the recording material) where the image is recorded, and the head cartridge 7 is opposed to the image recording position. Thereafter, an image is formed on the recording material by the head cartridge 7 ejecting ink toward the recording material in response to a signal from the electric substrate 9.
[0028]
(D) Paper Discharge Unit The paper discharge unit 4 includes a paper discharge roller 41 that discharges a recording material on which image recording has been performed to the outside of the recording apparatus 1, and a rotatable spur 42 that contacts the paper discharge roller 41. Yes. The spur 42 rotates following the rotating paper discharge roller 41.
[0029]
With this configuration, the recording material on which an image is recorded below the carriage unit 5 is discharged by being sandwiched between the nip between the discharge roller 41 and the spur 42 and discharged to a discharge tray (not shown) or the like.
[0030]
(E) Cleaning unit The cleaning unit 6 includes a pump 60 that sucks ink from the nozzles of the recording head of the head cartridge 7, a cap 61 that prevents the nozzles of the head cartridge 7 from drying, and a face surface of the head cartridge 7 (discharge port formation). And a PG motor 69 as a drive source thereof.
[0031]
Next, details of the carriage unit 5 in the recording apparatus 1 of the present embodiment will be described.
[0032]
FIG. 3 is a perspective view of the carriage unit of the recording apparatus shown in FIG. 1 as viewed from the ink ejection surface side of the head cartridge, and FIG. 4 is a view of the carriage unit shown in FIG.
[0033]
As shown in FIG. 3, the carriage unit 5 includes a head fixing lever 51 that fixes the head cartridge 7 to the carriage 50, and a carriage cover 52 that guides the head cartridge 7 when the head cartridge 7 is mounted on the carriage 50. .
[0034]
In addition, the head cartridge 7 receives each of the electrical signals from the heater board 72 configured with nozzles that eject black ink, the heater board 73 configured with nozzles that eject color ink, and the electrical substrate 9 (FIG. 2). And an FPC (flexible circuit board) 71 for transmitting to the heaters of the heater boards 72 and 73. In the present embodiment, these heater boards 72 and 73 and the FPC 71 constitute an ink jet recording head which is an ink discharge portion.
[0035]
As shown in FIGS. 3 and 4, a head protection plate 52R and a head protection plate 52L are provided in the vicinity of both sides of the FPC 71 of the head cartridge 7 in the main scanning direction of the carriage 50, respectively. These are formed integrally with the carriage cover 52, and when the head cartridge 7 is attached to the carriage 50, the head cartridge 7 abuts and elastically deforms. Therefore, the relative distance between each head protection plate 52R, 52L and the FPC 71 can be determined with high accuracy and constant regardless of the manufacturing error of each head protection member 52R, 52L.
[0036]
FIG. 5 is a perspective view showing the head cartridge shown in FIG.
[0037]
The FPC 71 is fixed to the head cartridge 7 by bonding, and is configured to be easily peeled off from the end portions 71R and 71L on both sides thereof. Further, the thickness of the FPC 71 itself is as thin as about 200 μm, and if the jammed recording material is caught on the FPC 71, the FPC 71 may be peeled off or torn, which may cause a failure of the recording head. Therefore, in this embodiment, the head protection plates 52R and 52L shown in FIGS. 3 and 4 are provided in the carriage unit 5 so that the recording material is not caught by the FPC 71.
[0038]
FIG. 6 is a diagram showing the relationship between the distance between the ink discharge portion of the carriage portion shown in FIG. 4 and the recording material.
[0039]
As shown in FIG. 6, the carriage unit 5 is configured such that the surfaces of the head protection plates 52 </ b> R and 52 </ b> L protrude from the surface of the FPC 71. Therefore, when the distance between the recording material P conveyed to the image recording area below the carriage unit 5 and the FPC 71 is d1, and the distance between the recording material P and each of the head protection plates 52R and 52L is d2. And d1> d2.
[0040]
Therefore, when the carriage unit 5 scans in the right direction of FIG. 6, for example, if there is a curled or bent portion (edge portion) of the recording material P in front of the scanning direction, the recording material P First contacts the right head protection plate 52R of the carriage unit 5. When the carriage unit 5 further scans in the right direction, the right end 71R of the FPC 71 passes through a position facing the edge portion of the recording material P. However, since the distance between the end portion of the head protection plate 52R and the end portion 71R of the FPC 71 is very small, the edge portion of the recording material P does not contact the end portion 71R, and the recording head does not touch the recording material P. Will not be damaged by contact.
[0041]
Thereafter, when the carriage unit 5 further scans in the right direction, the end portion of the left head protection plate 52L passes through a position facing the edge portion of the recording material P. As shown in FIG. 6, since slopes are formed at the ends of the head protection plates 52R and 52L, at this time, the edge portion of the recording material P abuts on the slopes and travels along the slopes to cause the head protection plate 52L. It is sent smoothly to the surface. That is, the edge portion of the recording material P is not caught by the end portion of the head protection plate 52L. Therefore, the impact when the edge portion of the recording material P abuts against the end portion of the head protection plate 52L can be reduced, and the end portion of the head protection member 52L can be prevented from breaking the recording material. .
[0042]
Even when the carriage unit 5 scans in the left direction in FIG. In this case, the left end 71L of the FPC 71 is protected from the edge portion of the recording material P by the head protection plate 52L, and the edge of the recording material P is formed by the end 71R formed on the right head protection plate 52R. Part catching is prevented.
[0043]
As described above, the recording apparatus 1 according to the present embodiment is configured such that the head protection plates 52R and 52L are closer to the recording material than the FPC 71 of the head cartridge 7, so that the recording material may be jammed or curled. Even when this occurs, the edge of the recording material is prevented from being caught at the end of the FPC 71 during the scanning of the carriage unit 5, so that the recording head can be prevented from being damaged. Reliability can be improved.
[0044]
In the above description, an example is shown in which slopes are formed at the ends of the head protection plates 52R and 52L. However, other than this, even if curved surfaces are formed at the ends of the head protection plates 52R and 52L, Good.
[0045]
In the present embodiment, the head protection plates 52R and 52L are provided on both sides in the scanning direction of the head cartridge 7. However, when one end of the recording material P is not lifted, one side thereof is provided. Only a head protection plate may be provided.
[0046]
(Second Embodiment)
FIG. 7 is a front view of the carriage unit in the recording apparatus according to the second embodiment of the present invention. FIG. 8 is a diagram showing the relationship between the distance between the ink ejection unit of the carriage unit and the recording material shown in FIG. is there.
[0047]
The carriage unit 5 in this embodiment also includes head protection plates 52R and 52L on both sides of the FPC 71, and the surface of each head protection plate 52R and 52L is configured to protrude from the surface of the FPC 71. Also in this embodiment, the distance between the recording material P conveyed to the image recording area below the carriage unit 5 and the FPC 71 is d1, and the distance between the recording material P and each of the head protection plates 52R and 52L is d2. Where d1> d2 is satisfied.
[0048]
However, in this embodiment, the heater boards 72 and 73 protrude from the surface of the FPC 71, and these are closer to the recording material P than the FPC 71. Such a convex portion is formed to electrically connect the heater boards 72 and 73 to the FPC 71, and is sometimes unavoidable in manufacturing the recording head.
[0049]
When the relative distance between the recording material P and the head cartridge 7 is defined, the distance d3 between the convex portion and the recording material P is strictly controlled so that the distance d3 is smaller than the distance d2. The relationship d1>d2> d3 is satisfied. Therefore, when the recording material P on which the ink has been ejected curls or swells, the convex portion comes into contact with the recording material P and functions to keep the recording material P away from the head cartridge 7. Therefore, even if the convex portion forming the distance d3 is formed on the head cartridge 7, the head protection plates 52R and 52L do not prevent the end portions 71R and 71L of the FPC 71 from being protected.
[0050]
(Other embodiments)
The present invention is particularly advantageous in an ink jet recording apparatus that performs recording by forming flying droplets using thermal energy among ink jet recording methods.
[0051]
As its typical configuration and principle, for example, those performed using the basic principle disclosed in US Pat. Nos. 4,723,129 and 4,740,796 are preferable. This method can be applied to both the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). By applying at least one drive signal corresponding to the recorded information and giving a rapid temperature rise exceeding the nucleate boiling to the electrothermal transducer, the thermal energy is generated in the electrothermal transducer, and the recording head This is effective because film boiling occurs on the heat acting surface of the liquid, and as a result, bubbles in the liquid (ink) corresponding to the drive signal on a one-to-one basis can be formed. By the growth and contraction of the bubbles, liquid (ink) is ejected through the ejection opening to form at least one droplet. It is more preferable that the drive signal has a pulse shape, since the bubble growth and contraction is performed immediately and appropriately, and thus it is possible to achieve discharge of a liquid (ink) having particularly excellent responsiveness.
[0052]
As this pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further excellent recording can be performed by employing the conditions described in US Pat. No. 4,313,124 of the invention relating to the temperature rise rate of the heat acting surface.
[0053]
As the configuration of the recording head, in addition to the combination configuration (straight liquid channel or right-angle liquid channel) of the discharge port, the liquid channel, and the electrothermal transducer as disclosed in each of the above-mentioned specifications, the thermal action A configuration using US Pat. No. 4,558,333 and US Pat. No. 4,459,600, which disclose a configuration in which the portion is arranged in a bent region, is also included in the present invention.
[0054]
In addition, for a plurality of electrothermal transducers, Japanese Patent Application Laid-Open No. 59-123670 that discloses a configuration in which a common slit is used as a discharge portion of the electrothermal transducer, or an aperture that absorbs pressure waves of thermal energy is provided. 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 the discharge unit.
[0055]
In addition, it is preferable to add recovery means for the recording head, preliminary auxiliary means, and the like provided as the configuration of the recording apparatus of the present invention, since the effects of the present invention can be further stabilized. Specifically, capping means, cleaning means, pressurizing or suction means for the recording head, preheating means using a heating element different from this, or a combination thereof, or recording is used. Performing a preliminary discharge mode for performing another discharge is also effective for performing stable recording.
[0056]
Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but the recording head may be configured integrally or may be a combination of a plurality of colors. The present invention is extremely effective for an apparatus having at least one of full colors.
[0057]
In the embodiment of the present invention described above, the ink is described as a liquid. However, the ink is solidified at room temperature or lower and softens at room temperature, or is liquid, or the above-described ink jet system. In general, the temperature of the ink itself is adjusted within a range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within a stable discharge range. Any liquid can be used.
[0058]
In addition, it is possible to prevent the temperature rise by heat energy from being used as the energy for changing the state of the ink from the solid state to the liquid state, or to use ink that solidifies in the standing state for the purpose of preventing ink evaporation. In any case, thermal energy such as ink that liquefies by application according to a recording signal of thermal energy and ejects as liquid ink, or that starts to solidify when it reaches the recording medium, etc. The use of ink having the property of being liquefied for the first time is also applicable to the present invention. In such a case, the ink is held as a liquid or solid in a porous sheet recess or through-hole as described in JP-A-54-56847 or JP-A-60-71260, It is good also as a form which opposes with respect to an electrothermal converter. In the present invention, the most effective one for each of the above-described inks is to execute the above-described film boiling method.
[0059]
In addition, as a form of the recording apparatus according to the present invention, a copying apparatus combined with a reader or the like, as well as an image output terminal of an information processing device such as a word processor or a computer, or a transmission / reception function It may be in the form of a facsimile machine having
[0060]
As described above , according to the ink jet recording apparatus of the present invention, it is possible to prevent the recording head from coming into contact with the recording medium and being damaged.
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating an overall configuration of a recording apparatus according to a first embodiment of the invention.
FIG. 2 is a side sectional view of the recording apparatus shown in FIG.
FIG. 3 is a perspective view of the carriage unit of the recording apparatus illustrated in FIG. 1 as viewed from the ink ejection surface side of the head cartridge.
4 is a front view of the carriage section shown in FIG. 3. FIG.
5 is a perspective view showing a state in which the head cartridge shown in FIG. 3 and the like is removed from the carriage. FIG.
6 is a diagram illustrating a relationship between a distance between an ink discharge unit of the carriage unit illustrated in FIG. 4 and a recording material.
FIG. 7 is a front view of a carriage unit in a recording apparatus according to a second embodiment of the invention.
8 is a diagram illustrating a relationship between a distance between an ink discharge unit of the carriage unit illustrated in FIG. 7 and a recording material.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Recording device 2 Paper feed part 3 Paper feed part 4 Paper discharge part 5 Carriage part 6 Cleaning part 7 Head cartridge 8 Chassis 8a Control part 9 Electric board 20 Base 21 Pressure plate 22 Feeding rotary body 23 Movable side guide 24 Pressure plate spring 30 Pinch Roller guide 31 Pinch roller spring 32 PE sensor 34 Platen 35 PE sensor lever 36 Transport roller 37 Pinch roller 41 Paper discharge roller 42 Spur 50 Carriage 51 Head fixing lever 52 Carriage cover 52R, 52L Head protection plate 56 Flexible cable 60 Pump 61 Cap 62 Wiper 69 PG motor 71 FPC (flexible circuit board)
71R, 71L End portions 72, 73 Heater board 80 Carriage motor 81 Guide shaft 82 Guide rail 83 Timing belt 84 Idle pulley 101 Linear encoder 102 Linear scale P Recording material

Claims (2)

And the heater board in which the nozzles are configured to eject ink, an ink jet recording apparatus for recording on a recording medium by a recording head having a flexible circuit board, the transmitting electrical signals to said heater board,
A carriage that removably mounts the recording head and reciprocally scans the recording medium;
A carriage cover for guiding the recording head when the recording head is mounted on the carriage;
A head protection plate formed integrally with the carriage cover and elastically deformed by contacting the recording head when the recording head is mounted on the carriage;
The distance between the recording medium arranged at a position facing the recording head and the head protection plate is smaller than the distance between the recording medium and the flexible circuit board, and the distance between the recording medium and the heater boat An ink jet recording apparatus characterized by being larger than the distance . The inkjet recording apparatus according to claim 1, wherein a slope or a curved surface is formed at an end of the head protection plate on the flexible circuit board side .

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