JP4318052B2 - Inkjet printer - Google Patents

Description

  The present invention relates to an ink jet printer that forms an image by ejecting ink onto a print medium.

  2. Description of the Related Art Conventionally, in an inkjet printer that performs printing by ejecting minute ink droplets from a plurality of ejection openings provided in an inkjet head, main scanning that ejects ink while moving the inkjet head in the main scanning direction (paper width direction) A so-called serial head type printer that performs printing by combining the movement operation in the direction and the operation of moving the paper in the sub-scanning direction, and a line head having a print width corresponding to the paper width of the paper as the print medium. There is a so-called line head type printer that performs printing while relatively moving the line head and the paper. Particularly, in the line head type printer, it is not necessary to move the ink jet head in the main scanning direction of the paper, and the printing speed can be increased as compared with the serial head type printer.

  In both the conventional serial head type printer and the line head type printer, in order to obtain a good image, it is necessary to maintain good ink discharge from the fine nozzles provided in the ink jet head. . For this reason, by discharging the ink inside the ink jet head, a purge operation for discharging foreign matter or bubbles present in the ink flow path, or by wiping the ink discharge surface where the ink discharge port of the nozzle is provided to the discharge surface. A recovery operation for properly ejecting minute ink from the nozzle, such as a wiping operation for removing extraneous ink droplets and foreign matters attached, is performed.

  In the serial head type printer, since the inkjet head is movable in the main scanning direction due to its structure, the inkjet head is retracted outside the printing area on the extension line in the main scanning direction to perform the purge operation and the wiping operation. It is possible.

  However, the line head type ink jet head has a wider ink discharge surface than the ink jet head of the serial head type printer, and if the recovery operation is performed by moving the ink jet head out of the printing area in the horizontal direction in the printer, the apparatus becomes larger. Leads to. Therefore, in the line head type ink jet printer, the recovery operation can be performed by inserting a maintenance unit that performs the recovery operation between the ink jet head and the medium transport device while the inkjet head is fixed in the horizontal direction. Conventionally done.

  Patent Documents 1 and 2 disclose a technique for performing an ink jet head recovery operation in a line head printer. According to the printer disclosed in Patent Document 1, during the recovery operation, the conveyor belt is moved in a direction (downward) away from the inkjet head, or the upper surface of the conveyor belt is upstream in the medium conveyance direction of the inkjet head. Alternatively, the maintenance unit is inserted into a gap formed between the inkjet head and the transport belt from the direction orthogonal to the medium transport direction of the transport belt by pressing downward on the downstream side.

  Further, in Patent Document 2, maintenance is performed by swinging the conveyance belt together with the other roller from the inkjet head, with one of the two rollers supporting the conveyance belt as a bridge. A space is formed so that the unit faces the discharge surface.

JP 2002-120386 (pages 10 to 11, FIG. 13) Japanese Unexamined Patent Publication No. 2000-62151 (pages 5-6, FIG. 1)

  However, in the ink jet printer described in Patent Document 1, since the maintenance unit is inserted from the direction perpendicular to the medium conveyance direction of the conveyance belt, the space in which the maintenance unit stands by other than during the recovery operation is separated from the conveyance belt. It is necessary to install on the side. Further, in the ink jet printer described in Patent Document 2, the conveyor belt is swung from the position where the conveyor belt faces the ejection surface of the inkjet head in a state where the conveyor belt is stretched downward with one roller supporting the conveyor belt as an axis. Since it is retracted by moving it, at least a space for swinging the stretched conveyor belt is required. Therefore, in the above-described conventional technique, there is a problem that it is difficult to reduce the size of the apparatus in order to secure a space necessary for moving the transport belt or a space necessary for moving the maintenance unit.

  Accordingly, an object of the present invention is to provide an ink jet printer that solves the above-described problems and can reduce the size of the apparatus by effectively using the space inside the apparatus.

In order to solve the above-described problem, the invention according to claim 1 is an ink jet printer having a discharge surface provided with a discharge port for discharging ink, and printing disposed opposite to the discharge surface. An inkjet head that performs printing by ejecting ink onto a medium, an endless loop-shaped conveyance belt that conveys and conveys the print medium on an outer peripheral surface, and the print medium carried on the outer peripheral surface faces the ejection surface A first roller and a second roller that support the conveyor belt so as to support the outer peripheral surface in a facing state opposite to the discharge surface, and a frame that rotatably supports the first roller; provided in the frame, a flat belt support member supporting from the inner peripheral surface side of the conveyor belt, a transfer unit having, while contacting the lower surface of the belt support member Has a cam for moving said first roller, from said operating position the conveyor belt is supported in the opposing state, the cam times to move to the retracted position than the operating position approaches the second roller the Rukoto is moving, a roller moving mechanism which apart from the facing position facing the ejection surface also bent from the opposite state the conveyor belt,
A cap provided on the elastic sheet and capable of covering the discharge surface; a wire fixed to the elastic sheet parallel to the transport direction of the print medium; and two fixed to both ends of the wire and a bobbin, by winding the wire on the bobbin by rotating the two bobbins, the cap, and recovery position opposing the ejection surface between the conveyor belt and the ejection surface, A cap moving mechanism for moving between a standby position facing the outer peripheral surface of the transport belt opposite to the side facing the discharge surface of the transport belt, and the transport belt separated from the facing position in the state, and a cap moving mechanism control means for moving to the recovery position from the standby position to the cap, the cap is stopped by reaching the recovery position , Wherein Rukoto said the roller moving mechanism rotates the cam, it is brought into close contact with the cap so as to cover the ejection surface pressed against the ejection surface such that the first roller is moved into the operating position And

According to a second aspect of the present invention, in the ink jet printer according to the first aspect, when the cap moves between the recovery position and the standby position, the cap does not come into contact with the transport unit. A guide member for guiding is provided.
According to a third aspect of the present invention, in the ink jet printer according to the second aspect, the guide member is a plurality of guide rollers, and the wire is guided between the bobbins by the guide rollers. Features.

According to a fourth aspect of the present invention, in the ink jet printer according to any one of the first to third aspects, the second roller is a driving roller that rotates by being transmitted with a driving force. The roller is a driven roller that is rotated by transmitting a rotational force generated by the rotation of the second roller via the conveyor belt.

According to a fifth aspect of the present invention, in the ink jet printer according to any one of the first to fourth aspects, the cap is formed from the first roller when the transport belt is separated from the facing position. It is inserted into the recovery position from the first roller side in the direction toward the second roller.

The invention according to claim 6 is the ink jet printer according to any one of claims 1 to 5 , further comprising an ink absorbing member that absorbs ink from the cap at the standby position. .

  According to the present invention, the conveyor belt is bent during the recovery operation of the inkjet head to retract the conveyor belt from the ejection surface, and therefore the space in which the conveyor belt moves and the conveyor belt when the conveyor belt retracts are disposed. The space can be reduced, and thus the ink jet printer can be reduced in size.

  An ink jet printer according to a preferred embodiment of the present invention will be described below.

  The ink jet printer of the present invention performs a recovery operation by the maintenance unit in order to recover the ink jet head to an appropriate state. At this time, it is necessary to retreat the conveying belt facing the ejection surface during printing so as to be separated from the ejection surface, so as to form a space where the maintenance unit faces the ejection surface of the inkjet head.

  In the ink jet printer of the present invention, in order to retract the transport belt, at least one of the rollers that span the transport belt is moved to bend the transport belt to retract the transport belt. By bending and retracting the conveyor belt, the degree of freedom of the path for moving the conveyor belt is increased compared to the conventional case where the conveyor belt is retracted without being bent in a state where the conveyor belt is stretched between two rollers. It is possible to reduce the belt moving space. Furthermore, the space occupied by the conveyor belt in a state where the conveyor belt is retracted can be reduced. In addition, the maintenance unit can stand by at a position close to the discharge surface, and the moving space of the maintenance unit can be reduced. Therefore, according to the present invention, it is possible to reduce the size of the entire inkjet printer.

  Preferred embodiments of the present invention will be described below with reference to the drawings. (Overall Configuration of Printer) First, an ink jet printer according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a side view illustrating the overall configuration of the ink jet printer 10 according to the present embodiment, and FIG. 2 is an explanatory diagram illustrating the configuration and operation of the roller moving mechanism 34 in the present embodiment.

  An ink jet printer 10 shown in FIG. 1 is a line head type color ink jet printer having four line type ink jet heads 12 inside a casing 11. That is, it is a line printing type inkjet printer in which the position of the inkjet head 12 is fixed at the time of printing and an image is formed on a print medium conveyed by a conveyance unit 20 described later. A sheet tray 14 is provided at the bottom of the casing 11 of the inkjet printer 10, a paper discharge tray 18 is provided at the top, and a transport unit 20 having a transport belt 25 is provided at the center in the figure. Is formed so as to pass through the lower part of the inkjet head 12 to form an image. The inkjet printer 10 also includes a movable maintenance unit 40 for performing a recovery operation for recovering the head main body 13 of the inkjet head 12 to an appropriate state.

  (Image Forming Mechanism) The four inkjet heads 12 have a head body 13 at the lower end. The head main body 13 is formed by bonding a flow path unit in which an ink flow path including a pressure chamber is formed and an actuator unit that applies pressure to the ink in the pressure chamber. Each of the head main bodies 13 has a rectangular cross section, and the longitudinal direction of the head main body 13 is perpendicular to the paper transport direction (medium transport direction, the direction of arrow A in FIG. 1) (the direction perpendicular to the paper surface in FIG. 1). Are arranged close to each other. The bottom surfaces (ejection surfaces 13a) of the four head bodies 13 are opposed to the sheet conveyance path. These discharge surfaces 13a are provided with a large number of discharge ports having a minute diameter corresponding to a nozzle, and magenta (M), yellow (Y), cyan (C), and black (K) from the four head bodies 13, respectively. Ink is ejected.

  The inkjet head 12 is arranged so that a slight gap is formed between the ejection surface 13a and the conveyance belt 25, and a sheet conveyance path is formed in this gap portion. With this configuration, when the paper transported on the transport belt 25 sequentially passes immediately below the four head bodies 13, ink of each color is ejected from the ink ejection port toward the upper surface (printing surface) of the paper. Thus, a desired color image is formed on the paper.

  The ink jet printer 10 performs a recovery operation in order to maintain good ink discharge from the fine nozzles provided in the head body 13. The recovery operation is performed when the ink is initially introduced from the ink supply source (not shown) to the inkjet head 12, or when the printer 10 is not used for a long period of time and then resumed. What constitutes the main part of the recovery operation is a discharge operation for preventing the ink in the vicinity of the discharge port from drying when a purge operation for pressurizing and removing the ink inside the inkjet head 12 from the discharge port or a printing operation is not performed. This is a capping operation for sealing the surface 13a.

  In this embodiment, the purging operation and the capping operation are performed by a maintenance unit 40 described later. The maintenance unit 40 is configured to be movable between a standby position separated from the discharge surface 13a and a recovery position facing the discharge surface 13a shown in FIG.

  (Configuration of Paper Conveying System) The paper feed tray 14 is provided with paper feed rollers 15 for stacking paper and feeding the uppermost paper of the stacked paper. The paper sent out by the paper feed roller 15 is sent out to the transport unit 20 by the feed roller 16 provided on the paper transport path while being guided by the guide frame 17 constituting the paper transport path. Then, the paper P is carried on the transport belt 25 of the transport unit 20, and an image is formed by the ink jet head 12. Thereafter, the paper P is discharged to the discharge tray 18 by the feed roller 16 while being guided by the guide frame 17.

  (Configuration of Transport Unit) The transport unit 20 includes a first roller 22, a second roller 24, and a transport belt 25 that is stretched between both rollers. The first roller 22 is rotatably supported by the frame 30 (roller support member, see FIG. 2) at both ends thereof. Further, a driving belt 28 for transmitting the driving force of the transport motor 27 is stretched around the second roller 24 which is a drive roller, and the second roller 24 rotates as the transport motor 27 rotates. It has become. The first roller 22 is a driven roller that is rotated by the rotational force of the conveyor belt 25 by applying a rotational force to the conveyor belt 25 by the rotation of the second roller 24.

  The conveyor belt 25 is an endless belt formed in a loop shape from a flexible material such as rubber. The outer peripheral surface 26 of the transport belt 25 is treated with silicon rubber. While the transported paper is held on the outer peripheral surface 26 by adhesive force, the second roller 24 is driven to drive the downstream side in the medium transport direction ( It can be transported toward the left in Fig. 1.

When performing the printing operation, the first roller 22 maintains a state (opposing state) where the outer peripheral surface 26 of the conveying belt 25 is in a position (opposing position) facing the discharge surface 13a, as shown in FIG. In position (operating position). On the other hand, when performing the recovery operation described later, the first roller 22 is
In order to separate the transport belt 25 from the ejection surface 13a, the transport belt 25 is moved to a retracted position by a roller moving mechanism 30 described later. When the first roller 22 is in the operating position, the conveyor belt 25 is stretched while being tensioned by the first roller 22 and the second roller 24.

  As shown in FIG. 2A, the frame 30 is provided with a belt support roller 31. Further, the transport unit 20 is provided with a pressing roller 29 (see FIG. 1) corresponding to the position of the belt support roller 31 when the transport belt 25 is at the opposite position, and the pressing roller 29 by a spring mechanism (not shown). Is urged toward the outer peripheral surface 26 of the conveyor belt 25. Therefore, the press roller 29 and the belt support roller 31 can press the paper against the outer peripheral surface 26 of the transport belt 25 and reliably transport the paper so that the paper does not float from the outer peripheral surface 26.

  Further, as shown in FIG. 2A, the belt 30 is provided with a belt guide roller 32, and when the transport belt 25 is at the opposite position, the transport belt 25 is inserted in the same manner as the belt support roller 31. Support from the circumference. The belt guide roller 32 functions as a guide member that contacts the conveyance belt 25 from the inner peripheral surface and guides the bent state of the conveyance belt 25 when the first roller 22 moves from the operating position to the retracted position. When the first roller 22 moves from the operating position to the retracted position, the conveyor belt 25 bends. However, if the belt guide roller 32 is not provided, the conveyor belt 25 may come into contact with the maintenance unit 40 depending on the direction in which the conveyor belt 25 is bent. there is a possibility. However, such a problem can be avoided by guiding the direction in which the conveying belt 25 is bent by the belt guide roller 32.

  The frame 30 is provided with a belt receiving member 33 that supports the conveyor belt 25 from below when the first roller 22 moves from the operating position to the retracted position. As shown in FIG. 2B, the conveyance belt 25 bent by the belt receiving member 33 can be prevented from coming into contact with the maintenance unit 40, and the ink attached to the maintenance unit 40 is transferred to the conveyance belt 25. Can be prevented.

  (Roller Moving Mechanism) Next, when the recovery operation of the ejection surface 13a of the inkjet head 12 is performed, the first roller 22 is operated in order to separate the transport belt 25 from the position (opposite position) facing the ejection surface 13a. The roller moving mechanism 34 for moving from the position to the retracted position will be described with reference to FIG.

  The roller moving mechanism 34 is a mechanism for moving the frame 30 on which the first roller 22 is pivotally supported, and guides the moving direction by engaging the guide pin 35 and the guide pin 35 provided on the frame 30. The guide rail 36, the frame 30 is fixed by a fixing member 37, and a moving belt 38 that transmits a driving force for moving the frame 30, and a pair of belt pulleys 39 on which the moving belt 38 is bridged are configured.

  The guide rail 36 is a member in which a groove having a width slightly larger than the diameter of the guide pin 35 is formed, and is provided at both ends in the width direction of the transport belt 25 of the housing 11. One of the belt pulleys 39 is driven by a drive motor (not shown).

  As shown in FIG. 2A, the first roller 22 is pivotally supported by the frame 30 and moves together with the frame 30 when the moving belt 38 is driven. As shown in FIGS. 2A to 2C, the guide roller 35 provided on the frame 30 is guided by the guide rail 36, so that the first roller 22 moves depending on the arrangement of the guide rail 36. Move the route. At this time, the conveyance belt 25 is guided in its bent state by the belt guide roller 32, and the conveyance belt 25 can be prevented from contacting the maintenance unit 40. The roller moving mechanism also serves as a guide moving mechanism that moves the belt guide roller 32.

  In this embodiment, the case where the guide pin 35 abuts on the right end portion of the guide rail 36 in the figure is the case where the first roller 22 is in the operating position, and the guide pin 35 is located on the left end portion in the figure. The case of contact is the case where the first roller 22 is in the retracted position.

  As shown in FIG. 2C, the retracted position of the first roller 22 is a position at least separated from an area where the maintenance unit 40 moves to a position facing the ejection surface 13a (maintenance unit moving area). Any position may be used as long as the conveying belt 25 is separated from the discharge surface 13a. By minimizing the distance that the first roller 22 is separated from the maintenance unit 40 moving region, it is possible to save the space of the inkjet printer 10. Further, the retracted position of the first roller 22 is set by the second roller 24 in the direction from the first roller 22 to the second roller 24 when the transport belt 25 is in the facing state (in the present embodiment, the medium transport direction). Also, by setting the position on the upstream side, the space for retracting the first roller 22 on the downstream side in the conveyance direction of the second roller 24 (left side in FIG. 1) can be reduced, and space saving of the inkjet printer 10 can be achieved. Can be planned.

  (Maintenance unit) Next, the structure of the maintenance unit 40 in a present Example is demonstrated using FIG. 2 and FIG. FIG. 3 is an explanatory diagram showing the operation of each mechanism during the recovery operation.

  The maintenance unit 40 includes a frame 42, a cap 44, and a rotation shaft 46 that rotatably supports the frame 42 at one end of the frame 42.

  Four caps 44 corresponding to the four inkjet heads 12 are provided on a part of the upper surface of the frame 42. The cap 44 is formed of an elastic body such as rubber, and covers the ink discharge port group on the discharge surface 13a of the inkjet head 12 so that the cap 44 can be kept in close contact with the air tight. Further, a tube (not shown) is connected to each cap 44, and the ink discharged through the tube when the pressure purge is performed by pressurizing the ink in the inkjet head 12 to discharge the ink is shown. Not discarded in the waste ink reservoir. The purge method may be a suction purge in which a pump is connected to the tube and ink in the inkjet head 12 is sucked and discharged using a suction force generated by driving the pump.

  Below the frame 42, a cam 48 (unit moving mechanism) connected to a drive motor (not shown) is provided at a position where its peripheral surface comes into contact with the bottom surface of the frame 42. When the cam 48 is rotated by a driving force of a drive motor (not shown), the frame 42 is rotated with the rotation shaft 46 as a fulcrum, and the maintenance unit is in a recovery position where the cap 44 faces the discharge surface 13a (FIG. 2 ( c) and FIG. 3 (c)) and a standby position (see FIG. 2 (a) and FIG. 3 (a)) separated from the discharge surface 13a.

  As shown in FIG. 1, the standby position of the maintenance unit 40 is the side facing the discharge surface 13a of the conveyor belt 25 when viewed from the first roller 22 and the second roller 24 when the conveyor belt 25 is in an opposing state. Is a position facing the outer peripheral surface 26 of the conveying belt 25 on the opposite side (lower side). As described above, the maintenance unit moving region can be reduced by setting the standby position so that the maintenance unit 40 faces the transport belt 25.

  (Recovery Operation) Next, the recovery operation in the inkjet printer 10 having the above-described configuration will be described with reference to FIG. Note that when performing the recovery operation, the operation of the roller moving mechanism 34 and the unit moving mechanism is controlled by a unit moving mechanism control device (not shown).

  FIG. 3A is a diagram illustrating a state when a printing operation is performed. At this time, the first roller 22 is located at the operating position so that the outer circumferential surface 26 of the conveyor belt 25 faces the ejection surface 13a. The maintenance unit 40 is located at a standby position which is a position facing the outer peripheral surface opposite to the outer peripheral surface facing the discharge surface 13a of the transport belt 25. In such an arrangement, the sheet is conveyed and an image is formed by the inkjet head 12.

  When performing the recovery operation, first, the first roller 22 is moved from the operating position to the retracted position as described above, and the conveying belt 25 is separated from the discharge surface 13a as shown in FIG. The belt 25 is separated from the maintenance unit moving area.

  Next, when the cam 48 is rotated, the frame 42 of the maintenance unit 40 is pushed upward, and the cap 44 is in close contact with the ejection surface 13a of the inkjet head 12 as shown in FIG. The maintenance unit 40 moves to In this state, the inkjet head 12 performs a purge operation for increasing the pressure of the ink flow path and discharging the ink in the nozzles into the cap 44. When the purge operation is completed, the maintenance unit 40 is fixed at the position until the next printing operation is started, and the ink in the nozzles is dried by maintaining the cap 44 in close contact with the ejection surface 13a. Prevent capping.

  As described above, in the inkjet printer 10 according to the present embodiment, the conveyance belt 25 is bent by moving the first roller 22 in order to form a space for the maintenance unit 40 to face the ejection surface 13a. . Therefore, compared with the case where the transport belt 25 is moved without being bent, the space required for separating the transport belt 25 from the position facing the discharge surface 13a may be small, and the standby position of the maintenance unit 40 may be further increased. Since it is possible to approach the ejection surface 13a, the internal space of the inkjet printer 10 can be used effectively, and the apparatus can be downsized.

  In this embodiment, the movement path of the first roller 22 defined by the guide rail 36 is a direction in which the first roller 22 moves away from the discharge surface 13a as the first roller 22 approaches the second roller 24 ( (Downward) is formed in a straight line shape, but may be a curved line, a straight line or a combination of curved lines, and the inkjet printer 10 can be downsized in consideration of the position where the maintenance unit 40 is disposed. It is desirable to arrange the guide rails 36 in such a shape as shown.

  FIG. 4 is a view showing a modification of the first embodiment, and shows a case where the conveyor belt 25 is in an opposing state (FIG. 4A) and a case where it is separated from the discharge surface 13a (FIG. 4B). Show. In the modification shown in FIG. 4, the shape of the guide rail 36 when projected in the width direction of the transport belt 25 is a convex curve toward the discharge surface 13 a. In this case, the moving path of the first roller 22 (frame 31) determined by the guide rail 36a can be closer to the discharge surface 13a, and the standby position of the maintenance unit 40a is further increased than when the guide rail 36a is linear. Can be brought close to the ejection surface 13a, and the ink jet printer 10 can be miniaturized.

  FIG. 5 is a view showing another modification of the first embodiment, and shows a case where the conveyor belt 25 is in an opposing state (FIG. 5A) and a case where it is separated from the ejection surface 13a (FIG. 5B). )). In the modification shown in FIG. 5, the movement path of the first roller 22 defined by the guide rail 36b is along the direction (the direction parallel to the discharge surface 13a) from the first roller 22 toward the second roller 24. It is formed as follows. In this case, since the first roller 22 moves at an equal distance from the discharge surface 13a, the standby position of the maintenance unit 40b is set to the discharge surface 13a in a range where the conveyance belt 25 bent when the roller is retracted does not contact the maintenance unit 40b. It becomes possible to approach.

  In the example shown in FIG. 5, the maintenance unit 40b is configured to move in parallel to a direction (vertical direction) orthogonal to the ejection surface 13a. Thus, the configuration of the unit moving mechanism that moves the maintenance unit between the standby position and the recovery position is not limited to the above configuration, and the maintenance unit can be moved from the standby position to the recovery position. Any configuration can be appropriately changed.

  In this embodiment, only the first roller 22 is moved. However, the second roller 24 is also moved with respect to the first roller 22 so that the conveying belt 25 is bent and separated from the discharge surface 13a. It may be configured to move relatively.

  Next, a preferred embodiment of the present invention different from the first embodiment will be described with reference to FIG. FIG. 6 is a diagram illustrating a main part of the inkjet printer 100 according to the second embodiment. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description may be omitted.

  As shown in FIG. 6A, the inkjet printer 100 is movable to perform a recovery operation for recovering the transport unit 102 for transporting paper by the transport belt 25 and the head body 13 of the inkjet head 12 to an appropriate state. A maintenance unit 120 is provided.

  Of the first roller 22 and the second roller 24 that bridge the conveyance belt 25, the second roller 24 is a drive roller that is driven by a driving force transmitted from a drive motor (not shown). The first roller 22 is a driven roller that is rotatably supported by the frame 104 at both ends thereof.

The frame 104 that supports the first roller 22 is provided with a flat belt support member 106 that supports the transport belt 25 from the inner peripheral surface side. Frame 104 is movably supported by a link member 108 of the strip-shaped, rotating while contacting the bottom surface of the movable frame 104 belt support cam 110 disposed below the belt member 106 supports 106 Is done. Therefore, a roller moving mechanism for moving the first roller 22 from the operating position to the retracted position is realized by the link member 108 and the cam 110. When the recovery operation of the head main body 13 of the inkjet head 12 is performed, the first roller 22 moves from the operating position shown in FIG. 6A to the retracted position shown in FIG. 6B by the action of the roller moving mechanism. .

  The maintenance unit 120 is formed by integrally forming a cap 124 for covering the ejection surface 13a on the flexible and elastic elastic sheet 122 by the same member as the elastic sheet 122. The cap 124 covers the ink discharge port group on the discharge surface 13a of the ink jet head 12 and can be in close contact with the air tight, and can prevent the ink in the head body 13 from drying. .

  Two wires 126 are embedded in both ends of the elastic sheet 122 in the width direction in parallel to the medium conveyance direction (the direction of arrow B in FIG. 6), and the elastic sheet 122 is fixed to the wires 126. Both ends of the two wires 126 are fixed to two bobbins 128 and 130, respectively. The wire 126 is guided between the bobbin 128 and the bobbin 130 by the guide roller 132 so as not to come into contact with the transport unit 102. The maintenance unit 120 can move between the recovery position and the standby position by rotating the bobbin 128 or 130 by the driving force of a motor (not shown). Therefore, the unit moving mechanism includes bobbins 128 and 130 and a motor (not shown) that drives both bobbins.

  The operation of the roller moving mechanism and the unit moving mechanism is controlled by a unit moving mechanism control device (not shown).

  An ink absorbing member 134 is provided at a position facing the cap 124 of the maintenance unit 120 in the standby position, and absorbs ink dropped from the cap 124.

  In the ink jet printer 100 having the above-described configuration, when performing the recovery operation, first, the cam 110 is rotated to move the first roller 22 to the retracted position as shown in FIG. As the first roller 22 moves to the retracted position, the conveyor belt 25 bends away from the ejection surface 13a, and a space is formed in which the maintenance unit 120 can be inserted into the recovery position. Even if the downward movement amount of the first roller 22 is small, the conveyance belt 25 bends to secure a space necessary for inserting the maintenance unit 120 into the recovery position.

  Next, the bobbin 128 is rotated by a drive motor (not shown) to wind the wire 126, and the maintenance unit 120 is inserted from the first roller 22 side to the recovery position.

  Then, as shown in FIG. 6C, when the maintenance unit 120 reaches the recovery position and stops, the cam 110 rotates again and the frame 104 rises. At this time, the maintenance unit 120 inserted between the conveyor belt 25 and the discharge surface 13a is pressed against the discharge surface 13a, and the cap 124 is in close contact with the discharge surface 13a. The maintenance unit 120 is fixed at the position until the next printing operation is started, and the cap 44 is kept in close contact with the ejection surface 13a, so that the ink in the nozzles can be prevented from drying. When performing the printing operation, the maintenance unit 120 moves to the standby position by a procedure reverse to the procedure for inserting it to the recovery position.

  As described above, in the inkjet printer 100 of the present embodiment, the conveyor belt 25 is bent by moving the first roller 22 in order for the maintenance unit 120 to form a space facing the ejection surface 13a. That is, as the first roller 22 approaches the second roller 24, the conveyance belt 25 is bent, and a space necessary for inserting the maintenance unit 120 without the second roller 24 moving is secured. Therefore, compared to the case where the transport belt 25 is moved without being bent, the amount of downward movement of the first roller 22 is small, so that the space required for retracting the transport belt 25 may be small. The internal space of the inkjet printer 100 can be used effectively, and space saving can be achieved.

  In the present embodiment, the maintenance unit 120 performs only capping. However, a configuration may be adopted in which a tube is attached to the cap 124 and ink in the head main body 12 is discharged by pressurization or suction purge. Further, the elastic sheet 122 is provided with an ink absorbing member or a wiper member for wiping the ejection surface 13a, and the ejection surface 13a is wiped when moving from the standby position to the recovery position or when moving from the recovery position to the standby position. It may be configured.

  In this embodiment, only the first roller 22 is moved. However, the second roller 24 may be moved in a direction approaching the first roller 22. In this case, the amount of bending (the amount of bending) of the transport belt 25 is increased by the amount of movement of the second roller 24. Therefore, the first roller 22 required to secure a space necessary for inserting the maintenance unit 120 is used. The amount of movement can be made smaller than when the second roller 24 is not moved.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and can be appropriately changed within the technical scope described in the claims.

  For example, in addition to the belt in which the sheet-shaped rubber material is formed in a loop shape as described above, the conveyance belt 25 may be appropriately changed such as a belt formed by connecting a plurality of strip-shaped plates. Is possible.

  In the first embodiment, the guide member (belt guide roller 32) that guides the bending direction of the transport belt 25 does not necessarily have to be disposed in contact with the transport belt 25 from the inner peripheral surface side of the transport belt 25. The configuration may be such that the belt 25 is in contact with the outer peripheral surface of the belt 25 for guidance.

  In the first embodiment, the roller moving mechanism 34 that moves the first roller 22 also serves as a guide moving mechanism that moves the guide member (belt guide roller 32). However, the guide moving mechanism is the roller moving mechanism 34. You may comprise by another mechanism. In this case, the guide moving mechanism needs to be controlled to operate in conjunction with the roller moving mechanism.

1 is a side view illustrating an overall configuration of an inkjet printer according to Embodiment 1. FIG. It is explanatory drawing explaining the structure and operation | movement of a roller moving mechanism in Example 1. FIG. It is explanatory drawing which shows operation | movement of each mechanism at the time of performing recovery | restoration operation | movement in Example 1. FIG. FIG. 6 is an explanatory diagram illustrating a modified example of the first embodiment. FIG. 6 is an explanatory diagram illustrating a modified example of the first embodiment. FIG. 10 is an explanatory diagram illustrating the operation of each mechanism when performing a recovery operation according to the second embodiment.

DESCRIPTION OF SYMBOLS 10 Inkjet printer 11 Housing | casing 12 Inkjet head 13 Head main body 13a Ejection surface 14 Paper feed tray 15 Paper feed roller 18 Paper discharge tray 20 Conveyance unit 22 1st roller 24 2nd roller 25 Conveyance belt 30 Frame 31 Belt support roller 32 Belt guide Roller 33 Belt receiving member 34 Roller moving mechanism 35 Guide pin 36 Guide rail 37 Fixed member 38 Moving belt 39 Belt pulley 40 Maintenance unit 42 Frame 44 Cap 46 Rotating shaft 48 Cam 100 Inkjet printer 102 Transport unit 104 Frame 106 Belt support member 108 Link member 110 Cam 120 Maintenance unit 122 Elastic sheet 124 Cap 126 Wire 128 Bobbin 130 Bobbin

Claims (6)

An ink jet head having a discharge surface provided with a discharge port for discharging ink, and performing printing by discharging ink to a print medium disposed opposite to the discharge surface;
An endless loop-shaped conveyance belt that conveys the print medium supported on the outer peripheral surface, and an opposing surface that faces the discharge surface so that the print medium supported on the outer peripheral surface faces the discharge surface. A first roller and a second roller for supporting the conveyor belt so as to be supported in a state; a frame for rotatably supporting the first roller; and an inner peripheral surface of the conveyor belt provided on the frame. A transport unit having a flat belt support member supported from the side ;
A cam that rotates while contacting the lower surface of the belt support member, and the first roller is closer to the second roller than the operation position from the operation position where the conveying belt is supported in the facing state. the Rukoto rotates the cam so as to move to the retracted position, and a roller moving mechanism which apart from the facing position facing the ejection surface also bent from the opposite state the conveyor belt,
A cap provided on the elastic sheet and capable of covering the discharge surface ;
A wire fixed to the elastic sheet in parallel with the transport direction of the print medium, and two bobbins fixed to both ends of the wire, and rotating the two bobbins to by winding the bobbins, the cap, and recovery position opposing the ejection surface between the conveyor belt and the ejection surface, opposite to the ejection surface and opposite to that side of the conveyor belt A cap moving mechanism for moving between the outer peripheral surface of the conveyor belt and a standby position facing the outer peripheral surface ;
In a state in which the conveyor belt is spaced apart from the facing position, and a cap moving mechanism control means for moving to the recovery position from the standby position to the cap,
After the cap is stopped by reaching the recovery position, the first roller is a roller moving mechanism to move into the operating position by rotating the cam, pressing the cap on the ejection surface inkjet printer, wherein Rukoto is adhered so as to cover the ejection surface. The inkjet printer according to claim 1, further comprising a guide member that guides the cap so that the cap does not come into contact with the transport unit when the cap moves between the recovery position and the standby position. The inkjet printer according to claim 2 , wherein the guide member is a plurality of guide rollers, and the wire is guided between the bobbins by the guide rollers. The second roller is a driving roller that is rotated by being transmitted with a driving force,
Said first roller, an ink jet according to any one of claims 1 to 3, wherein the rotational force by the rotation of the second roller is transmitted via the conveyor belt is a driven roller that rotates Printer. The cap is inserted from the first roller side to the recovery position in the direction from the first roller to the second roller when the transport belt is in a state of being separated from the facing position. the ink jet printer according to any one of claims 1 to 4, characterized. The ink jet printer according to any one of claims 1 to 5, characterized in that an ink absorbing member for absorbing the ink from the cap on the standby position.

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