JP2007331283A - Inkjet recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet recording apparatus with an inexpensive constitution, which is equipped with an ink mist recovery mechanism capable of preventing the retention of an ink mist in an image forming portion, and of preventing the diffusion of the ink mist to the outside of the apparatus. <P>SOLUTION: This inkjet recording apparatus comprises: a suction fan 100 which is arranged on a side wall 46 at one end, in the direction of the movement of a carriage 20, of a case 40; an air supply opening 111 which is provided in a side wall 47 at the other end, in the direction of the movement of the carriage, of the case; and ink mist recovery members 104 and 117 for removing the ink mist in the air by coming into contact with the air discharged from the suction fan. Additionally, a circulating duct 107 for guiding the air, from which the ink mist is removed, to the air supply opening is provided. The air discharged from the suction fan is circulated into the case through the circulating duct and the air supply opening, after the removal of the ink mist. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ink jet recording apparatus that performs recording by discharging ink to a recording medium from a recording head mounted on a carriage that reciprocates. Specifically, the present invention relates to an ink jet recording apparatus provided with an ink mist collecting mechanism for discharging and collecting ink mist generated in an image forming unit.

  As an output device such as a computer or a workstation, a recording device having functions such as a printer, a copying machine, or a facsimile is known. The recording apparatus is configured to form an image (including characters and symbols) on a recording medium such as paper, cloth, a plastic sheet, an OHP sheet, an envelope, or the like by a recording head based on image information. There are a serial type and a line type as a scanning method in the recording apparatus. The serial type is a method in which an image is recorded while alternately repeating main scanning for moving the recording head along the recording medium and sub-scanning for feeding the recording medium at a predetermined pitch. The line type is a system in which an image is recorded only by paper feeding (sub-scan) of a recording medium while recording one line at a time. The recording apparatus can be classified into an ink jet type, a thermal transfer type, a laser beam type, a thermal type, a wire dot type, and the like depending on the recording type.

  An ink jet type ink jet recording apparatus forms an image by discharging ink from a discharge port of a recording head to a recording medium based on image information. The recording head of the ink jet recording apparatus is provided with an ejection port array composed of an array of ejection ports for ejecting ink. In the case of color recording, a plurality of ejection port arrays are provided for each ink color. . In a serial type ink jet recording apparatus, a recording head is mounted on a carriage that moves in the main scanning direction, and an image is recorded by driving the recording head in synchronization with the movement of the carriage. Then, the recording of the entire recording medium is performed by alternately repeating recording for one line and feeding a predetermined amount of paper. The present invention relates to an ink jet recording apparatus that performs recording while moving a recording head along a recording medium.

  When an image is formed on a recording medium with such an ink jet recording apparatus, the recording medium being conveyed is temporarily stopped. Then, ink is selectively ejected from a plurality of ejection openings based on the image signal while reciprocating the carriage, thereby recording one line in a region facing the recording head. After recording for one line, the recording medium is conveyed (paper fed) by a predetermined pitch, and the next line is recorded. A target image is formed on the recording medium by alternately repeating such recording for one line and paper feeding.

  In an ink jet recording apparatus, an image is formed by ejecting liquid ink. Therefore, when ink is ejected from the ejection port of the recording head, fine mist-like ink (ink mist) is generated around the ink droplet. . Also, when ink droplets land on the recording medium, not all of the ink droplets are instantaneously attracted to the recording medium, and some of the ink droplets bounce off the surface of the recording medium due to impact of the landing or the like. In some cases, the rebounded ink scatters in the form of mist and becomes ink mist. The generated ink mist is wound up inside the recording apparatus by a negative pressure generated rearward in the movement direction as the carriage moves. The wound ink mist becomes floating ink and adheres to components and members inside the recording apparatus.

When the user's hand touches these parts and members, the hand becomes dirty with the adhered ink. Also, when ink mist adheres to the carriage sliding mechanism, carriage positioning encoder, or the like, the recording apparatus may malfunction due to the influence of the attached ink mist. Therefore, as a mechanism for removing such ink mist, for example, in Patent Document 1, air inside the recording apparatus is sucked and discharged by a suction fan disposed at an end of the image forming unit, thereby removing ink mist in the air. A recovery mechanism is disclosed.
JP 2004-25718 A

  In recent years, in an ink jet recording apparatus, ink droplets ejected from a recording head have been increasingly miniaturized in order to cope with high image quality. For this reason, the amount of ink mist generated is also increasing. On the other hand, in the ink jet recording apparatus, the movement distance of the carriage becomes longer due to the expansion of the width dimension of the medium (recording medium), and the length and volume (volume) of the housing provided in the image forming unit so as to surround the carriage also increase. ing. For this reason, the conventional ink mist collection mechanism has a disadvantage that the ink mist remains in the vicinity of the center of the carriage movement range even if suction is performed by suction fans provided at both ends of the apparatus main body in order to enhance the collection capability. It was.

  As a countermeasure, a method of increasing the suction force by increasing the number of rotations of the suction fan can be considered. However, this method requires a special fan having a high suction power or increases the number of suction fans. For this reason, the ink mist collecting mechanism in the conventional ink jet recording apparatus has the disadvantages of increasing the cost and increasing the noise particularly when applied to a large apparatus.

  The present invention has been made in view of such technical problems. SUMMARY OF THE INVENTION An object of the present invention is to provide an ink jet recording apparatus having an ink mist collecting mechanism that can prevent ink mist from staying in an image forming unit and prevent ink mist from spreading outside the apparatus with an inexpensive configuration. It is.

  The present invention relates to an ink jet recording apparatus in which a recording head is mounted on a carriage that reciprocates in a housing, and recording is performed by discharging ink from the recording head to a recording medium based on image information. In the present invention, a suction fan disposed on the side wall of one end of the casing in the carriage movement direction and an air supply port provided on the side wall of the other end of the casing in the carriage movement direction are provided. Further, an ink mist collecting member that removes ink mist in the air by coming into contact with the exhaust air from the suction fan, and a circulation duct for guiding the air from which the ink mist has been removed to the air supply port are provided. And after removing ink mist, the exhaust air from a suction fan is circulated in a housing | casing through a circulation duct and an air supply port.

  According to the present invention, there is provided an ink jet recording apparatus having an ink mist collecting mechanism that can prevent ink mist from staying in an image forming unit and prevent ink mist from spreading outside the apparatus with an inexpensive configuration. .

  Embodiments of the present invention will be specifically described below with reference to the drawings. Note that the same reference numerals denote the same or corresponding parts throughout the drawings. FIG. 4 is a front perspective view of the ink jet recording apparatus according to the embodiment of the present invention. FIG. 5 is a rear perspective view of the ink jet recording apparatus of FIG. FIG. 6 is a partially broken perspective view showing the configuration of the image forming unit of the ink jet recording apparatus according to the embodiment of the present invention. 4 and 5, the ink jet recording apparatus 10 is fixed to the top of a stand 12 with casters 12a. The recording apparatus 10 has an operation unit 14. The paper size, online / offline, command, and the like can be instructed by various switches installed on the operation unit 14.

  A recording medium insertion port 16 for inserting a recording medium such as roll paper or cut paper from the direction of arrow A is provided on the back surface of the recording apparatus 10. The recording medium inserted from the recording medium insertion port 16 is conveyed inside the recording apparatus based on an instruction from the operation unit 14 and is recorded in the image forming unit. The recorded recording medium is discharged from the recording medium discharge port 18 in the arrow B direction. The ink jet recording apparatus of the illustrated form is suitable for recording an image on a large recording medium such as roll paper. Inside the ink jet recording apparatus 10, an image forming unit for recording an image on the recording medium 11 by an ink jet recording head 22 as shown in FIG. 6 is provided.

  Next, the configuration and operation of the image forming unit will be described with reference to FIG. The illustrated ink jet recording apparatus can record an image on either a sheet-like recording medium (cut paper or the like) or a recording medium (roll paper or the like) wound in a roll. Here, the case of recording on roll paper inserted from the recording medium insertion port 16 will be described. However, a sheet-like recording medium can be inserted from this insertion port, and the recording operation in that case is also substantial. Is the same. On the back surface of the recording apparatus 10, a roll shaft around which the roll paper 11 is wound is rotatably held. The rolled paper 11 is fed in the direction of arrow A from the recording medium insertion port 16. The image forming unit is provided with a platen 34 for supporting the back surface of the recording medium 11 conveyed in the direction of arrow A.

  Above the platen 34, two guide rails 36 extending in the paper width direction are installed in parallel. A carriage 20 on which a recording head (inkjet recording head) 22 is mounted is guided and supported along two guide rails 36 so as to reciprocate in the directions of arrows D and E. The carriage 20 is slidably supported with respect to the guide rail 36 via a slide bearing. The illustrated recording head 22 is a recording head capable of color recording, and includes four recording head portions (ink ejection portions) 22K, 22C, 22M, and 22Y. These ink discharge sections (recording head sections) are provided with discharge port arrays that discharge black, cyan, magenta, and yellow inks. A part of the transport roller 24 extending in the paper width direction is exposed from an opening (not shown) formed in the platen 34. Further, on the upper side of the platen 34, a pinch roller 26 pressed against the conveying roller 24 is rotatably supported at positions at predetermined intervals in the paper width direction.

  The roll paper 11 is sandwiched between the transport roller 24 and the plurality of pinch rollers 26 and is rotated in the direction of arrow A by rotating the transport roller with a motor (not shown). When forming an image, the recording heads 22K, 22C, 22M, and 22Y are recorded on the basis of image information by a head control unit (not shown) while moving the carriage 20 in the directions of arrows D and E (main scanning) above the roll paper 11. To eject ink. As a result, an image is formed on a portion of the roll paper 11 positioned in the image forming area. By alternately repeating the image formation by the recording head 22 and the pitch conveyance (paper feeding) of the roll paper 11, a target image is recorded in a target range. The roll paper that has finished forming an image in the predetermined range is cut into a predetermined size by the cutting device 38 and discharged. Thereby, the operation of the image forming unit is temporarily ended. In the ink jet recording apparatus, ink mist is generated when ink is ejected from the ejection ports 22K, 22C, 22M, and 22Y as described above.

  FIG. 1 is a front cross-sectional view showing a configuration of an ink mist collecting mechanism in an image forming unit of an ink jet recording apparatus according to an embodiment of the present invention and a state when a carriage is located substantially at the center. FIG. 2 is a front sectional view showing a state where the carriage is positioned closer to the suction fan in the ink mist collecting mechanism of FIG. FIG. 3 is a front sectional view showing a state where the carriage is positioned closer to the air supply port in the ink mist collecting mechanism of FIG. In FIG. 1, the image forming unit of the ink jet recording apparatus 10 is surrounded by an outer package 45, and a casing 40 surrounding the image forming unit is configured by this outer package. The carriage 20 can reciprocate in the left-right direction along the guide rail 36 inside the housing 40. By this reciprocation, the main scanning of the recording medium at the time of recording is performed. When ink is ejected from the recording head 22 on the carriage 20 such as during image formation, ink mist is generated in the housing 40.

  A suction fan 100 for discharging the air in the housing is disposed on the side wall 46 that partitions the image forming unit provided at one end (on the right side in the drawing) of the housing 40 in the carriage movement direction. An exhaust duct 103 is formed on the discharge side of the suction fan 100. In addition, an air supply port for supplying air to the side wall 47 that partitions the image forming unit provided at the other end (on the left side in the drawing) of the case 40 in the carriage movement direction. 111 is provided. The exhaust duct 103 is formed so as to extend downward along the outside of the side wall 46 of the casing 40 and further extend along the lower side of the casing. The exhaust duct 103 is connected to the circulation duct 107 via a mesh-like mist trap 117. The circulation duct extends along the lower side of the housing 40 and then communicates with an air supply port 111 provided in the side wall 47. Therefore, the exhaust air from the suction fan 100 is difficult to be sent to the circulation duct 107 through the exhaust duct 103 and the mist trap 117, and can be circulated from the air supply port 111 into the housing 40.

  Therefore, an ink absorber 104 as an ink mist collecting member for removing (capturing) ink mist in the air by contacting the exhaust air from the suction fan 100 is mounted inside the exhaust duct 103. Yes. The exhaust duct 103 communicates with the mist collection box 105 (waste ink collection box) through the opening 108 at a position before the mist trap 117. An ink absorber 104 is also loaded inside the mist collection box 105. Therefore, also in the mist collection box 105, the ink mist in the exhaust air from the suction fan 100 can be captured. Ink mist that has not been removed by the ink absorber 104 in the exhaust duct 103 is also captured and recovered by a mesh-like mist trap 117 provided between the exhaust duct and the circulation duct 107. This mist trap 117 also constitutes an ink mist collecting member together with the ink absorber 104.

The ink mist thus captured by the ink absorber 104 and the mist trap 117 is collected in the mist collection box 105 through the ink absorber and the mist trap. The ink jet recording apparatus of this embodiment is provided with the ink mist collection mechanism as described above. Thus, by removing the ink mist from the exhaust air, it is possible to prevent the ink mist from spreading outside the apparatus (outside the apparatus).
Further, the mist collection box 105 is provided with an out-of-machine discharge fan 106 for discharging the air flowing into the mist collection box from the opening 108 to the outside of the apparatus. In other words, when the external discharge fan 106 is operated, a part of the air discharged from the suction fan 100 can be discharged outside the apparatus. The air discharged to the outside of the apparatus is the air from which the ink mist has been removed by the ink mist collecting mechanism described above.

  Air that has passed through the exhaust duct 103 and the mist trap 117 (air from which ink mist has been removed) is supplied into the housing 40 from the air supply port 111 via the circulation duct 107. That is, it is circulated into the housing 40. The supplied air is blown from the side of the carriage 20 in the housing 40 toward the upper part from the lower side. As a result, an airflow that flows toward the suction fan 100 on the opposite side is generated above the movement range (scanning range) of the carriage 20. By this air flow, the ink mist in the housing 40 is moved to the vicinity of the suction fan 100 as shown in FIG.

  As described above, the air exhausted from the suction fan 100 for collecting ink mist can be used to generate an airflow passing through the image forming unit in the housing 40. According to this air flow, even in a large-sized ink jet recording apparatus, ink mist generated in the apparatus can be discharged out of the housing without staying in the apparatus, and the discharged ink mist can be efficiently collected. Further, the air (part thereof) from which the ink mist has been removed by the ink mist collecting member can be discharged by the external discharge fan 106. Thus, a negative pressure can be maintained in the housing, and the ink mist can be more effectively prevented from spreading outside the apparatus. That is, the air purified by the ink absorber 104 or the like is discharged outside the apparatus by the outside discharge fan 106 before being returned to the circulation duct 107. For this reason, the circulation air supply amount from the air supply port 111 can be reduced, and the exhaust amount from the suction fan 100 can be increased. Thus, by realizing the condition “exhaust amount> air supply amount” in the circulation type ink mist collecting mechanism, the ink mist generation space can be maintained in a negative pressure state.

  Next, a method for controlling the amount of air discharged by the suction fan 100 and the amount of circulating air from the air supply port 111 according to the position of the carriage 20 in the circulating ink mist collecting mechanism according to the present embodiment will be described with reference to FIGS. explain. As shown in FIG. 2, when the carriage 20 being driven is positioned closer to the suction fan 100 (either during movement or when stopped), the volume between the carriage 20 and the suction fan 100 (in-machine volume) is narrow. The volume between the carrier 20 and the air supply port 111 (in-machine volume) is large. In this case, the number of rotations of the suction fan 100 is increased, and control is performed to increase both the amount of air discharged from the suction fan 100 and the amount of air supplied from the air supply port 111 (the amount of air supply 116). A circulating air flow rate in the housing 40, which is a traveling space, is secured. Thereby, the ink mist in the housing 40 can be moved to the vicinity of the suction fan 100, and the ink mist can be effectively discharged by the suction fan. At the same time, by maintaining the inside of the housing 40 at a negative pressure, it is possible to prevent the ink mist from diffusing outside the apparatus together with the ink mist collecting members (ink mist capturing members) 104 and 117.

  As shown in FIG. 3, when the driving carriage 20 is positioned closer to the air inlet 111 (either during movement or when stopped), the volume between the carriage 20 and the suction fan 100 (in-machine volume) is The volume between the carriage 20 and the air inlet 111 (in-machine volume) is small. In this case, the amount of air discharged from the suction fan 100 needs to be increased by the increase in the in-machine volume, and at the same time, the amount of air supplied from the air supply port 111 (the amount of the air supply 116) needs to be suppressed. For this reason, an out-of-machine exhaust fan 106 configured in the exhaust duct 103 is used. That is, by driving the external discharge fan 106 simultaneously with the suction fan 100, the amount of exhaust from the housing 40 can be increased as compared with the case of the suction fan 100 alone. Then, the amount of air returned to the circulation duct 107 is reduced by discharging the air to the outside by the outside discharge fan 106, thereby suppressing the amount of air supplied from the air supply port 111. Thus, by maintaining the inside of the housing 40 at a negative pressure, it is possible to more effectively prevent the ink mist from spreading outside the apparatus. In this case, the position of the carriage 20 can be detected by detection means such as a linear encoder, and the driving of the suction fan 100 and the external discharge fan 106 can be controlled based on the detection result.

  According to the embodiment described above, the exhaust air from the suction fan 100 is circulated into the housing 40 through the circulation duct 107 and the air supply port 111 after removing the ink mist. Accordingly, it is possible to prevent the ink mist from staying in the image forming unit and to prevent the ink mist from diffusing outside the apparatus with an inexpensive configuration. Furthermore, the amount of air discharged from the casing and the amount of air supplied to the casing can be controlled while generating a circulating airflow in the casing surrounding the image forming unit. Further, by arranging the external exhaust fan 106 in the exhaust duct 103 and adjusting the exhaust air amount and the air supply amount by the external exhaust fan, the inside of the housing 40 can be maintained at an appropriate negative pressure. This makes it possible to effectively collect the ink mist while preventing the ink mist from spreading outside the apparatus more effectively. Further, the inside of the housing can be maintained at a negative pressure by making the amount of air discharged from the suction fan 100 variable according to the position of the carriage 20 in the housing 40. This also makes it possible to improve the ink mist collection performance while effectively preventing the ink mist from diffusing outside the apparatus.

  Further, since the ink mist in the casing 40 is discharged by the suction fan while being collected in the vicinity of the suction fan 100 by the circulating airflow, it is possible to reliably prevent the ink mist from remaining in the central portion of the image forming unit. Since the discharge air amount and the air supply amount are controlled in accordance with the change in the discharge volume depending on the position of the carriage 20, it is possible to simultaneously stabilize the discharge performance of the ink mist and prevent the ink mist from spreading outside the apparatus. Can do. Furthermore, according to the above-described embodiment, it is not necessary to increase the number of fans used or to use a fan with a special high exhaust performance, and to improve the ink mist collection performance by controlling the normal fan rotation speed. Can do. Accordingly, it is possible to improve the ink mist collection performance with an inexpensive configuration and without generating a large noise. As a result, there is provided an ink jet recording apparatus that can prevent image quality deterioration due to ink mist and can easily form a high quality image.

  In the above embodiment, the case where the present invention is applied to an ink jet recording apparatus has been described as an example. The present invention is not limited to a single recording apparatus such as a printer, a copying machine, a facsimile, or a captured image forming apparatus. The present invention can be widely applied as a recording apparatus in a composite apparatus combining these or a composite apparatus such as a computer system. In addition, the present invention can be similarly applied when applied to a recording apparatus, regardless of the number and arrangement of recording heads, and can be similarly applied to an inkjet recording apparatus regardless of the type or properties of ink. It is. The present invention can be applied to a recording medium regardless of the material and form as long as it can record an image, such as paper, cloth, plastic sheet, OHP sheet, and envelope.

FIG. 3 is a front cross-sectional view illustrating a configuration of an ink mist collection mechanism in an image forming unit of an ink jet recording apparatus according to an embodiment of the present invention and a state when a carriage is positioned substantially at the center. FIG. 2 is a front sectional view showing a state where a carriage is positioned closer to a suction fan in the ink mist collecting mechanism of FIG. FIG. 3 is a front cross-sectional view showing a state where the carriage is positioned closer to the air supply port in the ink mist collecting mechanism of FIG. 1. 1 is a front perspective view of an ink jet recording apparatus according to an embodiment of the present invention. FIG. 5 is a rear perspective view of the ink jet recording apparatus of FIG. 4. 1 is a partially broken perspective view illustrating a configuration of an image forming unit of an ink jet recording apparatus according to an embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inkjet recording device 20 Carriage 40 Case of image forming part (carriage moving part) 45 Exterior 46 47 Side wall 100 Suction fan 103 Exhaust duct 104 Ink absorber 105 Ink collection box 106 External discharge fan 107 Circulation duct 116 Air supply 117 Mist trap

Claims (7)

In an inkjet recording apparatus in which a recording head is mounted on a carriage that reciprocates within a housing, and recording is performed by discharging ink from the recording head to a recording medium based on image information.
A suction fan disposed on a side wall of one end of the casing in the carriage movement direction;
An air supply port provided on the side wall of the other end of the casing in the carriage movement direction;
An ink mist collecting member that removes ink mist in the air by contacting the exhaust air from the suction fan;
A circulation duct for guiding the air from which the ink mist has been removed to the air supply port;
With
An ink jet recording apparatus, wherein air discharged from the suction fan is circulated into the housing through the circulation duct and the air supply port after removing ink mist.   An exhaust fan outside the machine is disposed in the exhaust duct of the suction fan, and the inside of the housing is negatively adjusted by adjusting the amount of air exhausted from the suction fan and the amount of circulating air from the air supply port by the exhaust fan outside the machine. 2. The ink jet recording apparatus according to claim 1, wherein the pressure can be maintained.   3. The inkjet recording apparatus according to claim 1, wherein the inside of the housing is kept at a negative pressure by varying an amount of air discharged from the suction fan in accordance with a position of the carriage in the housing. .   4. The ink jet recording apparatus according to claim 1, wherein the ink mist collecting member is configured of an ink absorber disposed in an exhaust duct of the suction fan. 5.   5. The ink jet recording apparatus according to claim 1, wherein the ink mist collecting member includes a mesh mist trap disposed in an exhaust duct of the suction fan.   When the carriage is located closer to the suction fan, the number of rotations of the suction fan is increased to increase the amount of air exhausted from the suction fan and the amount of air supplied from the air supply port. The ink jet recording apparatus according to claim 1, wherein an air flow rate is ensured.   When the carriage is positioned closer to the air supply port, the air discharge fan is driven simultaneously with the suction fan to increase the amount of exhaust air and suppress the air supply amount to the air supply port. An ink jet recording apparatus according to any one of claims 2 to 6.

Images