JP2007118545A - Picture recording device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a picture recording device which can maintain an image recording position and a maintenance position to a proper recording head with a simple configuration by eliminating effects even if distortion in an apparatus frame or an unevenness component precision is generated. <P>SOLUTION: A roller 36b-1 of the end of a platen support 36b which performs rising and falling of a platen part 30 having a conveying mechanism is supported elastically by a compression spring used as an elastic member. At the maintenance position, a maintenance part 60 is raised in superposition on the platen part 30 elastically biased by the set ability of a compression spring 100, and supported by immobility (elastic power bias immobility condition), at the upper image recording position, a compression spring is contracted by a load which is made to bring into contact with an image recording mechanism 20 and exceeds set capability, (elastic power bias movable condition) supported by movability to constitute an image forming apparatus. Thereby, the proper operation of a maintenance unit 61 is not disturbed at the maintenance position without the operation of the elasticity, and at the recording position, a recording medium on the image recording mechanism 20, and a conveyance mechanism provides proper spacing. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image recording apparatus for recording an image on a recording medium conveyed by an endless belt represented by a line head type ink jet printer or the like to which a recording head is fixed.

  In recent years, with the spread of computers, image recording apparatuses such as printers used as peripheral devices have also become widespread. This image recording apparatus takes out, for example, an A4 or B5 size cut sheet accommodated as a recording medium in a supply cassette or the like, conveys the image information when passing through the front of the image recording unit, and discharges the cassette. It is stored in.

  An image recording apparatus includes an ink jet recording method using a line-type fixed recording head that does not scan and move during image recording. In this recording method, when an endless belt is used as one of the conveying means, a cut sheet is sucked or adsorbed to the endless belt and conveyed in front of the ink discharge port of the line type fixed recording head. In addition, ink is discharged over the entire width of the cut sheet.

  In such an image recording apparatus, the gap between the endless belt and the recording head is set very narrow, for example, 1 mm or less. For this reason, when the cut sheet is jammed for some reason during the image information recording operation, it is necessary to make a space for removing the jammed cut sheet by moving the belt conveyance unit away from the recording head. Also, when performing the recovery operation of the recording head, the maintenance section must be inserted below the recording head. To insert the maintenance section, the belt conveying section is moved in the apparatus to create a space. There is a need.

  For example, Patent Document 1 discloses an apparatus provided with a support releasing mechanism that separates the belt conveyance unit from the recording head in a substantially parallel state in order to secure a space for performing jam processing between the belt conveyance unit and the recording head. Has been proposed. Specifically, a belt conveyance unit is provided on the recording apparatus main body so as to be able to swing around the driving roller on one end side around which the endless belt is wound, and the driving roller is centered when the cut sheet is jammed. A configuration in which the other end side of the belt conveying unit can be separated from the recording head is disclosed. Furthermore, a configuration is also disclosed in which the belt conveying unit can be raised and lowered while maintaining a parallel state with respect to the recording head by the lifting mechanism.

The line-type fixed recording head for recording a color image has at least four recording heads of black, yellow, magenta, and cyan arranged along the recording medium conveyance direction. Therefore, each time the recording medium transported by the belt from the upstream side passes in front of the ink ejection port of each recording head, each color ink is ejected to form a color image. These recording heads are held by the main body frame, and a belt conveyance mechanism configured to be movable up and down is also held by the main body frame via a link, an arm, and the like. Further, as a maintenance mechanism, a recovery cap portion is provided to appropriately remove ink clogging in the nozzles and maintain the recording head in a state where recording is possible at all times.
Japanese Patent No. 2816217

  In the recording apparatus of Patent Document 1 described above, in order to maintain the recording head by the recovery cap portion, the belt platen portion is retracted by the lifting mechanism, and then the posture of the recording head portion is changed, thereby freeing space. The recovery cap portion is inserted so as to face the recording head. These series of operations are complicated and require separate driving means, resulting in an increase in size and cost of the apparatus. In addition, the control mechanism is complicated in order to accurately position the recording head and the recovery cap during maintenance.

  In addition, the recording head, the recovery cap unit, and the like are mounted on the apparatus frame (main body frame). The weights of the lifting and lowering mechanisms of the belt platen part and the recovery cap part are always loaded on the apparatus frame, and the load is repeatedly applied to the main body frame by the operation of each mechanism. For this reason, the device frame cannot be set correctly when the load balance is lost due to the floor condition at the installation location and the torsion or distortion occurs, and the recording head and recovery cap section cannot be set correctly. There is also a drawback in that the image cannot be positioned at the proper position and cannot be opposed to each other, and good image recording and maintenance cannot be performed.

  In addition, the accuracy of manufactured parts has varied, so even if it is within the standard as a non-defective product, if the setting conditions are strict, a combination of many parts will increase the total error. During adjustment, errors may occur gradually due to changes over time even when operating normally.

  The present invention provides an image recording apparatus capable of maintaining the image recording position and the maintenance position with respect to an appropriate recording head with a simple configuration even when distortion and variations in component accuracy occur in the apparatus frame. The purpose is to provide.

  The present invention provides an image recording unit capable of recording an image over the entire recording width of a recording medium, a maintenance unit that recovers ink ejection by acting on an ink ejection port of the image recording unit, and the image recording unit. A recording medium conveyance unit that is disposed to face and holds the recording medium and conveys the recording medium in a direction orthogonal to the width direction of the recording medium, and the recording medium conveyance unit in contact with the recording medium conveyance unit And a maintenance unit that can be moved up and down, and a variable interval mechanism that varies a distance between the recording medium transport unit and the maintenance unit with respect to the image recording unit, and a variable interval mechanism, and at least during a maintenance operation by the maintenance unit Urges in the direction to reduce the interval, supports the maintenance unit in an immobile state by urging elastic force, and the recording medium transport unit performs the maintenance operation. Of a position at which an image recording apparatus and an elastic biasing mechanism for supporting the movable state by the urging of the resilient force of the recording medium conveying unit in a position close to the image recording unit.

  The present invention also provides an image recording unit capable of recording an image over the entire recording width of a recording medium, a maintenance unit that acts on an ink ejection port of the image recording unit to recover ink ejection, and the image recording unit And a recording medium transport unit that holds the recording medium and transports the recording medium in a direction perpendicular to the width direction of the recording medium, and abuts on the recording medium transport unit, and the recording medium transport unit And an interval variable mechanism for varying an interval between the image recording unit and the maintenance unit, and a part of the abutting portion of the recording medium conveyance unit, and the recording medium conveyance unit is elastically disposed with respect to the interval variable mechanism. And an elastic urging mechanism that supports the recording medium conveyance unit during the maintenance operation by the maintenance unit, and the recording medium conveyance unit is configured to support the recording medium conveyance unit. In a position close to the image recording unit than the position in the nonce operation, to provide an image recording apparatus that the recording medium conveying unit to elastically support.

  The present invention absorbs variations in the relative positional relationship between units caused by distortion of the device frame and errors in parts accuracy, eliminates the influence, and maintains an appropriate image recording position and maintenance position with respect to the recording head with a simple configuration. Provided is an image recording apparatus capable of performing the above.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of an image recording apparatus according to the first embodiment of the present invention.
The image recording apparatus 1 includes at least a medium supply unit 10, an image recording mechanism 20, a platen unit 30, a discharge unit 50, a maintenance unit 60, an ink supply unit 70, a recording medium reversing unit 80, and a control unit 90. The unit is mounted on the apparatus frame 2 shown in FIG. In the following description of each embodiment, the conveyance direction of the recording medium is the X-axis direction or the sub-scanning direction, and the direction orthogonal to the conveyance direction is the Y-axis direction or the main scanning direction, or the width direction of the recording medium. Further, a direction perpendicular to the XY plane is defined as a Z-axis direction or a vertical direction.

  First, the concept of the image recording apparatus shown in FIG. 1 will be described. In the image recording apparatus, the platen unit 30 that configures the medium supply conveyance path so as to face the image recording mechanism 20 is supported by the platen drive unit 36 that configures the interval variable mechanism so as to be movable up and down. At the time of image recording, the four platen support portions 36b of the platen drive portion 36 stand up, rotate to the top stop point, and the platen frame 33 is pushed up by the tips (rollers 36b-1) of these platen support portions 36b. It has become. Accordingly, if there is a variation in the dimensions of the components during manufacturing and assembly, or if the apparatus frame 2 is distorted after the start of use, the tip of the platen support 36b (roller 36b- Variations occur in the height of 1). This variation in height is a problem of the conventional apparatus, and the ink head row 41 and the platen unit 30 that is the transport mechanism cannot be moved to an appropriate engagement position for engaging with the set recording position. There is a problem that damage is caused to an engagement mechanism, which will be described later, and that an appropriate facing position between the ink head row 41 and the maintenance unit 61 is shifted. In the present embodiment, even if there is a variation in the height of the tip (roller 36b-1) of the platen support portion 36b using an elastic body, for example, an elastic force of a compression spring, it is absorbed by moving elastically. The ink head row 41 and the platen unit 30 can be easily fixed at the image recording position by accurately setting them at appropriate positions.

First, the device frame 2 will be described with reference to FIG.
The apparatus frame (main body frame) 2 supports the medium supply unit 10, the image recording mechanism 20, the medium discharge unit 50, the maintenance unit 60, the ink supply unit 70, the recording medium reversing unit 80, and the control unit 90. In the following embodiments, the support includes supporting a support target via at least one other member and supporting directly without any other member. Furthermore, the support includes fixing and moving as well as supporting rotatably.

  The apparatus frame 2 has a rectangular base plate 2P. When the base plate 2P is disposed on a horizontal base surface, the upper surface thereof is horizontal. A pair of medium supply side front side walls 2Fa and 2Fb are provided upright on one side of the upper surface of the base plate 2P corresponding to the medium supply side. On the other hand, a pair of discharge side L-shaped side walls 2Ba and 2Bb are provided upright on the other side portion corresponding to the medium discharge side. The front side walls 2Fa and 2Fb are connected by width direction connecting portions 2Wa and 2Wb, and the medium discharge side L-shaped side walls 2Ba and 2Bb are connected by width direction connecting portions 2Wc and 2Wd. Further, the medium supply side side wall 2Fa and the medium discharge side L-shaped side wall 2Ba are connected by the longitudinal direction connecting portions 2La and 2Lb. The medium supply side wall 2Fb and the medium discharge side L-shaped side wall 2Bb are connected by longitudinal direction connecting portions 2Lc and 2Ld. In this way, the front side walls 2Fa and 2Fb and the rear L-shaped side walls 2Ba and 2Bb are fixedly supported on the base plate 2P.

  The front side walls 2Fa and 2Fb are provided with member support portions 2Fc (not shown) and 2Fd for supporting each portion constituting the image recording apparatus 1. The front side wall 2Fa and the member support portion 2Fc (not shown) have a hole 2Ha having a common axis. Similarly, the front side wall 2Fb and the member support portion 2Fc have a common axis. 2Hb is formed. A registration roller pair 13 described later is pivotally supported by these two holes 2Ha and 2Hb. Further, the width direction connecting portion 2Wc is provided with a support member (not shown) that supports a rear end portion of a carriage 42 described later at one point.

Next, the medium supply unit 10 will be described.
The medium supply unit 10 includes a recording medium tray 11, and a pickup roller 12 is disposed with respect to the recording medium tray 11. A registration roller pair 13 for performing position correction (skew correction) on the taken-out recording medium is disposed downstream thereof. The recording medium tray 11 can accommodate a plurality of recording media, for example, a plurality of cut sheets having a plurality of sizes such as A4 and B5. Note that the recording medium tray 11 may be configured as a reel that accommodates a roll-shaped recording medium.

The pickup roller 12 is a mechanism for taking out recording media stored in the recording media tray 11 one by one. The pickup roller 12 is rotatably supported on the front side walls 2Fa and 2Fb of the apparatus frame 2 described above.
The registration roller pair 13 includes a pair of a driving roller 13a and a driven roller 13b that are in contact with each other. The driving roller 13a is rotated by a driving force transmitted from a driving mechanism (not shown). The support structure for the registration roller pair 13 will be described later. In addition, the distance between the registration roller pair 13 and the pickup roller 12 is arranged at a distance that allows skew correction with respect to the recording medium. In the present embodiment, the conveyance path of the recording medium extending to the boundary between the medium supply unit 10 and the image recording mechanism 20 is referred to as a medium supply conveyance path.

  The registration roller pair 13 performs correction (skew correction) in the width direction (main scanning direction; X-axis direction) by bending the recording medium after the leading edge of the recording medium sent from the pickup roller 12 arrives. Thereafter, the image is transferred to the image recording mechanism 20 side.

  The pickup roller 12 and the driving roller 13a of the registration roller pair 13 are connected to a common driving force transmission system (not shown) composed of a motor and an encoder, and driving force is provided from this driving force transmission system. The driving force transmission system is connected to the control unit 90 and is driven according to a command from the control unit 90. Further, the pickup roller 12 and the registration roller pair 13 are configured to be able to be disconnected from the driving force transmission system by a clutch. These clutches are connected to the control unit 90, and ON / OFF is controlled by the control unit 90. The pickup roller 12 and the registration roller pair 13 are configured to be rotatable around the X axis.

Next, the image recording mechanism 20 will be described.
The image recording mechanism 20 includes a platen unit 30 and an image recording unit 40. The platen unit 30 is a recording medium transport mechanism that sucks and holds the recording medium fed from the registration roller pair 13 and transports the recording medium in front of the ink discharge port of the recording head with a predetermined interval. As shown in FIGS. 1, 3A, and 3B, the platen unit 30 includes a platen belt 31 having a plurality of suction holes 31a, a plurality of platen belt rollers 32, a platen frame 33, and a platen suction unit 34. And a platen drive 36. In FIG. 3 (a), only about half of the platen belt 31 in the Y-axis is shown for explanation.

  The platen belt 31 is an endless belt made of rubber or resin, and is suspended on a plurality of platen belt rollers 32 to constitute a belt conveyor. The region of the platen belt 31 that faces the image recording unit 40 is configured such that the recording medium that is conveyed properly faces the recording head. This area is called a platen recording medium conveyance area, and is indicated by reference numeral 31c in FIG.

  At least one of the platen belt rollers 32 is connected to a belt roller drive motor 32a that provides a rotational driving force. In addition, the upstream platen belt roller 32 is provided with a driven roller at a position facing the platen belt 31 with the platen belt 31 therebetween, thereby preventing the recording medium from being lifted.

  As shown in FIG. 3B, a platen suction part 34 that generates a negative pressure for adsorbing the recording medium is provided in the platen frame 33. The platen suction unit 34 includes a platen frame 33, first to third platen chambers 35a, 35b, and 35c, and a platen chamber negative pressure generation source 34a.

  The platen drive unit 36 constituting the interval variable mechanism has a pair of platen drive unit rotation shafts 36a. As shown in FIG. 1, the platen drive unit rotation shaft 36 a is disposed at both ends of the platen unit 30 on the Y axis so as to face each other on the Y axis. More specifically, one platen drive unit rotation shaft 36a (left side in FIG. 1) and the other platen drive unit rotation shaft 36a (right side in FIG. 1) face each other in the Y-axis direction. The platen part 30 is located below both ends of the Y axis.

The platen part positioning mechanism will be described with reference to FIGS.
Here, the Y (+) side is called the downstream side, the Y (−) side is called the upstream side, the X (+) side is called the front side, and the X (−) side is called the rear side.
On the platen frame head facing surface 33a side of the platen frame 33, platen guide holes 39a, 39b, and 39c for alignment with the image recording unit 40 are provided in an area that does not face the platen belt 31 (non-platen area). (See FIG. 5). In the present embodiment, platen guide holes 39a and 39c on the upstream front side and rear side in the recording medium conveyance direction, and platen guide holes 39b and 39c on the downstream front side and rear side, respectively. A total of four are provided.

A platen guide hole 39a is provided on the rear side upstream of the platen frame head facing surface 33a. As shown in FIG. 6, the platen guide hole 39a has a recess 39a-1 on the upstream side surface. The recess 39a-1 is formed with a right side shape on the upstream side surface. A pin 42c serving as a first fitting portion constituting an engagement mechanism provided in a carriage 42 described later is inserted into the recess 39a-1 formed with a right-angle shape on the upstream side surface (see FIG. 7). ). In the platen guide hole 39a, a parallel pin 39a-2 having an axial shape along the X-axis direction is disposed at a position facing the recess 39a-1. One end of a spring 39a-3 is brought into contact with the tip of the parallel pin 39a-2, and the pin 42c is pressed against the side surface of the recess 39a-1 by the elastic force of the spring 39a-3. With this force, the platen portion 30 is positioned on the carriage 42. Also, the platen guide hole 39a is not shown so as to cover the parallel pins 39a-2 and the springs 39a-3, leaving a hole portion into which the pin 42c is inserted. A cover is provided.

  On the other hand, the platen guide hole 39b disposed on the downstream front side is similarly configured. In this case, although details of the platen guide hole 39b are not shown, the platen guide hole 39b is constituted by a long hole parallel to a line connecting the center of the platen guide hole 39b and the center of the platen guide hole 39a. In addition, a pin (not shown) is pressed by the elastic force of the spring. The remaining two platen guide holes 39c have a sufficiently large diameter with respect to the outer diameter of the pin 42c, and do not interfere with the position of the pin positioned by the platen guide hole 39a and the platen guide hole 39b. Yes.

The platen driving unit 36 will be described with reference to FIGS. 1, 5, and 8 to 10.
The platen frame 33 has two sets of a pair of platen drive unit guides 33 c for guiding the platen drive unit 36. As shown in FIG. 5, these platen drive section guides 33c are provided on the opposite side to the platen frame head facing surface 33a in the Z axis. Further, the pair of platen driving unit guides 33c are provided at both ends of the platen frame 33 at positions separated in the Y-axis direction and the X-axis direction. These platen driving unit guides 33 c have guide surfaces along the Y axis and extend from the end of the platen frame 33 by a predetermined distance.

  Each platen drive unit rotation shaft 36a extends along the X axis and rotates around the X axis. More specifically, as shown in FIG. 8, each platen drive unit rotation shaft 36 a is placed on the X axis so as to face the platen drive unit guides 33 c disposed at both ends of the platen frame 33 on the X axis. Have dimensions along. The pair of platen driving unit rotating shafts 36a are connected to each other by a platen driving unit belt 36c (see FIG. 1) so that the rotational force can be transmitted to each other. A platen driving unit motor 36d is connected to one of the pair of platen driving unit rotating shafts 36a, and the platen driving unit belt 36c is rotated by the rotation of the platen driving unit motor 36d, and the pair of platen driving unit rotating shafts. 36a is rotated in synchronization with each other. The platen drive unit motor 36d is connected to the control unit 90, and the drive is controlled by the control unit 90.

  Each platen drive unit rotation shaft 36a supports a platen support unit 36b disposed in the Z-axis direction corresponding to the platen drive unit guides 33c at both ends in the X-axis direction of the platen frame 33. That is, two platen support portions 36b are provided for each platen drive portion rotation shaft 36a. Each platen support portion 36b has a platen drive portion rotation shaft 36a supported at one end and abuts the platen drive portion guide 33c at the other end. Accordingly, the four platen support portions 36b can rotate along the platen drive portion guide 33c in accordance with the rotation of the platen drive portion rotation shaft 36a.

  With such a configuration, the position of the Z-axis of the platen frame 33 changes depending on the contact position of the platen support part 36b in the platen drive part guide 33c. That is, the platen frame 33 moves up and down in the Z-axis direction according to the drive of the platen drive unit rotation shaft 36a. The platen frame 33 is disposed at the uppermost position in the Z-axis direction when the platen support portion 36b is parallel to the Z-axis direction.

  As shown in FIGS. 9 and 10, the platen support portion 36 b has a roller 36 b-1 that contacts the platen driving portion guide 33 c and moves the platen portion 30 up and down while rotating. The roller 36b-1 has a rotating shaft 36b-1a inserted into a U-shaped long hole 36b-2 formed at the tip of the arm 36b-3, and along the U-shaped long hole 36b-2, a platen The support part 36b is slidable in the longitudinal direction (see FIG. 10). The roller 36b-1 is provided with a bracket 36b-4. The bracket 36b-4 rotatably holds the rotation shaft 36b-1a of the roller 36b-1, slides the roller 36b-1 along the long hole 36b-2, and slides the arm 36b-3. It is comprised so that it may move (refer Fig.9 (a)).

  Further, as shown in FIG. 9B, the bracket 36b-4 is inserted into a hole formed in the bracket guide 36b-5 fixed to the arm 36b-3 so that the tip portion can be moved.

  A cutout 36b-7 is opened in the arm 36b-3, and a stopper 36b-4a fixed on the bracket 36b-4 is inserted into and attached to the cutout. The stopper 36b-4a moves in the notch 36b-7 to limit the moving range of the roller 36b-1 with respect to the longitudinal direction of the platen support 36b. Further, the compression spring 36b-6 is fitted in the bracket 36b-4 in a compressed state. Accordingly, the compression spring 36b-6 is in a state where the roller 36b-1 is pushed up by pressing the bracket 36b-4 in the longitudinal direction of the platen support 36b (the upper end in FIG. 9B). That is, when the load of the image recording mechanism 20 and the maintenance unit 60 is not applied to the roller 36b-1, that is, in a state where the tip of the platen support 36b is free, the bracket 36b-4 is compressed by the compressed compression spring 36b-6. Is biased toward the upper end of the arm 36b-3, and as shown in FIG. 9B, the bracket 36b-4 has a stopper 36b-4a pressed against the upper end of the notch 36b-7 of the arm 36b-3. It has become.

  The amount of force (elastic force) of the compression spring 36b-6 in this state is called a set force amount, and is a unit that is lifted by the platen support portion 36b in the vicinity of the maintenance operation position (in the first embodiment, the platen portion 30 and the maintenance portion 60). Is set to a value larger than the component force in the compression direction of the compression spring 36b-6 generated by the weight applied to the tip of each platen support 36b.

  11 and 12, the lower end of the maintenance unit 60 comes into contact with the upper surface of the platen unit 30 and is lifted upward, and the maintenance unit 61 of the maintenance unit 60 performs a maintenance operation facing the ink head unit 43 of the image recording mechanism 20. It is the perspective view and front view which show a state. FIG. 13 is a front view showing a state in which the maintenance unit 60 is further lowered together with the platen unit 30 in order to move the maintenance unit 60 so as to face or retract from the ink head unit 43. 11 and 13 are simplified views of only one ink head unit 43 and one recovery cap portion 61a included in the maintenance unit 61 corresponding thereto. FIG. 12 shows a simplified diagram of one ink head unit 43.

  In this embodiment, when the platen part 30 is lifted and held at the maintenance position by the platen support part 36b, the compression spring 36b-6 is in a state where the platen part 30 and the maintenance part 60 are loaded. The stopper 36b-4a is kept pressed against the upper end of the notch 36b-7 of the arm 36b-3. In other words, in a state where only the platen unit 30 and the maintenance unit 60 are mounted on the platen support unit 36b, the maintenance unit 61 of the maintenance unit 60 is not contracted from the state in which the compression spring 36b-6 generates the set force. It is possible to press the head unit 43 properly. Hereinafter, in the present invention, the state in which the stopper 36b-4a is pressed against the upper end of the notch 36b-7 by the elastic force of the compression spring 36b-6 and does not move is defined as an elastically biased state, and the region is elastically biased. This is referred to as a non-moving region (or simply an elastic non-moving region). That is, it means that the external force (load) is lower than the set force amount of the compression spring 36b-6, and the compression spring 36b-6 does not contract.

  Similarly, when the platen unit 30 is lifted and held at the image recording position by the platen support unit 36b, in addition to the load of the platen unit 30 and the maintenance unit 60, the image recording mechanism 20 is added to the compression spring 36b-6. When the roller 36b-1 is further pressed through the platen portion 30 and a force greater than the set force is applied, the compression spring 36-b6 is compressed, and the roller 36b-1 moves to the lower end side along the elongated hole 36b-2. It goes down, but it is elastic, but it can move. In this state, thereafter, even when a slight load is applied to the roller 36b-1 at the tip of the platen support 36b, the compression spring can be easily moved in the direction in which the compression spring expands or contracts. The state in which the compression spring 36b-6 expands and contracts and the roller 36b-1 moves in the longitudinal direction of the platen support portion 36b is defined as an elastic movable state (or simply an elastic state), and the region is elastically biased movable. This is referred to as a region (or simply an elastic movable region).

  As shown in FIG. 14, the compression spring 36b-6 starts to contract and the roller 36b-6 elastically moves from the point in time when the load applied to each platen support portion 36b exceeds the above-described force point to the compression spring 36b-6. Become. Accordingly, the compression spring 36b-6 at the maintenance position is in an elastically immovable state and is in an elastic immobile region, and the compression spring 36b-6 at the image recording position is in an elastically energized movable state and is in an elastic movable region.

Next, the rack mechanism 38 for suspending the platen unit 30 from the carriage 42 will be described.
In this case, the platen frame 33 of the platen portion 30 is provided with a rack mechanism 38 as a second fitting mechanism that constitutes an engagement mechanism on both the front side and the rear side (see FIGS. 4 and 5). As shown in FIG. 15, the basic structure of the rack mechanism 38 is engaged with a pin 42c of a carriage 42, which will be described later, and a slide hook 38-1 for hanging the platen portion 30 on the carriage 42, and these slide hooks 38-1. Are provided at both ends. In order to press the slide hook 38-1 against the lower surface of the platen frame head facing surface 33a and the rack member 38-2 that moves the slide hook 38-1 to the engaged state and the released state position with respect to the pin 42c. And a spring (not shown) for pushing up the slide hook 38-1 from the rack member 38-2. Further, as shown in FIG. 16, the slide hook 38-1 is formed so as to be compatible with recording media having different thicknesses depending on the position in the moving direction. For example, if the recording medium is a recording sheet, a plurality of positions can be taken including a normal sheet position, a thick sheet A position, a thick sheet B position, and an open position according to the thickness.

  The slide hooks 38-1 provided at both ends of the front rack member 38-2 are provided at positions facing the platen guide holes 39 c and 39 b at both front ends of the platen unit 30. The slide hooks 38-1 provided at both ends of the rear rack member 38-2 are provided at positions facing the platen guide holes 39 a and 39 c at both ends on the rear side of the platen portion 30.

  Each rack member 38-2 on the front side and the rear side has a rack drive gear 38-3 meshed with a rack portion 38-5 provided in the vicinity of the approximate center of the rack member 38-2, and the rack drive gear 38-3. Reciprocates in the Y direction. The rack drive gear 38-3 is driven by a rack drive motor (not shown), and its position is detected and controlled by a rack HPSW 38-4 which is a state detection means. More specifically, the home position at the position where the slide hook 38-1 is released from the pin 42c is detected by the rack HPSW 38-4, and the slide hook 38-1 is detected by the rack drive motor rotation angle from the home position position. The normal paper position, the thick paper A position, and the thick paper B position are controlled (see FIGS. 4 and 5).

Next, the image recording unit 40 will be described.
The image recording unit 40 has an ink ejection device for ejecting ink onto a recording medium. As shown in FIG. 19, the carriage 42 has a plurality of ink head rows 41 and a head cooling unit 49. These ink head arrays 41 are composed of a plurality of short recording heads arranged for recording an image. The ink head row 41 is provided for each color, and is arranged such that a plurality of short recording heads extend over the same or larger dimension as the maximum recording width of the recording medium to be used. .

  As shown in FIG. 1, the image recording unit 40 of this embodiment has a total of four ink head rows 41 of black (K), cyan (C), magenta (M), and yellow (Y). Yes. Further, in the image recording unit 40 in FIG. 1, for the sake of explanation, suffixes (K, C, M and Y) indicating the corresponding colors are added to the reference numerals indicating the respective ink head columns 41. .

  The carriage 42 includes a head attachment portion 42a to which the ink head row 41 is attached, a carriage hole 42b for exposing the ink head row 41 to the recording medium, a carriage alignment pin 42c for aligning the platen portion 30, and A pair of medium supply roller connecting portions 42d is provided. The ink head row 41 attached to the head attachment portion 42a is configured by arranging a plurality of ink head units 43 in a row with their longitudinal directions coinciding with each other.

  The ink head arrays 41 have a dimension in the longitudinal direction that is equal to or larger than the recording width dimension of the recording medium so that an image can be recorded over the entire recording width of the recording medium used for image recording. That is, when the image recording unit 40 supports recording for the entire width of the A3 recording medium, the width of the ink head row 41 is set to be equal to or larger than the width of the A3 recording medium. In the present embodiment, the ink head row 41 is composed of six ink head units 43. The number of the ink head units 43 constituting the ink head row 41 can be changed according to the recording width dimension of the recording medium to be used.

Next, the carriage 42 will be further described with reference to FIGS. 17 (a) and 17 (b).
First, the support portion for the medium supply roller connecting portion 42d and the registration roller pair 13 will be described.

  As shown in FIG. 17A, the pair of medium supply roller connecting portions 42d are fixed to both side portions (front side, rear side) of the head mounting portion 42a on the X axis so as to face each other. The pair of medium supply roller connecting portions 42d is a pair of medium supply roller bearing fitting portions 42e that support a bearing (not shown) of one roller (the lower drive roller 13a in FIG. 17B) of the registration roller pair 13. have.

  Further, an elongated hole 42f that supports the shaft of the other roller of the registration roller pair 13 (the upper driven roller 13b in FIG. 17B) so as to be movable up and down above the medium supply roller bearing fitting portion 42e. Is open. The registration roller pair 13 is pivotally supported by the medium supply roller connecting portion 42d, and both ends of the shaft protrude outside the two medium supply roller connecting portions 42d. Around the two protruding shafts, a nip spring 13c that is formed in an annular shape by connecting both ends of a tension spring is hung. The driven roller 13b is elastically biased toward the driving roller 13a by the nip spring 13c, thereby generating a nip pressure between the registration roller pair 13. Both shaft ends of the drive roller 13a extend further from the medium supply roller bearing fitting portion 42e and protrude outward from the holes 2Ha and 2Hb of the apparatus frame 2. The holes 2Ha and 2Hb are sized to have play with respect to the shaft of the drive roller 13a. Specifically, the bottom surfaces of the holes 2Ha and 2Hb with which the shaft of the driving roller 13a abuts are set to have a predetermined height with respect to the recording medium conveyance system. The amount of play allows a slight displacement in the paper transport direction (that is, the horizontal direction) and upward so that the drive roller 13a is supported only from the frame in the height direction even when the apparatus frame is deformed. It has a hole shape with play. The amount of play is determined by the position tolerance with respect to the paper conveyance system upstream and downstream of the registration roller pair 13. In FIG. 1, the medium supply roller connecting portion 42d is omitted for simplification of the drawing.

  The pair of medium supply roller bearings 42e are provided to face each other in the width direction of the head mounting portion 42a. As described above, the pair of medium supply roller bearings 42e sets the rotation center of one roller of the registration roller pair 13 in the width direction of the head mounting portion 42a. For this reason, the conveyance direction of the recording medium by the registration roller pair 13 is set to the longitudinal direction of the head mounting portion 42a.

  Accordingly, the longitudinal direction of the head mounting portion 42a can be set in parallel to the Y axis, which is the recording medium conveyance direction. Further, the width direction of the head mounting portion 42a coincides with the X axis. Accordingly, the carriage 42 can be rotated around the axis of the medium supply roller bearing 42e via the medium supply roller coupling portion 42d. In other words, the carriage 42 can rotate around the X axis.

  Next, the medium discharge side support portion 42m of the carriage 42 will be described with reference to FIGS. 18 (a) and 18 (b).

  At the medium discharge side end of the carriage 42, a medium discharge side support portion 42m having a protruding portion shape is provided near the approximate center in the medium width direction. The medium discharge side support part 42m is composed of a protrusion part 42m-1 and a spherical part 42m-2. The protrusion 42m-1 is formed integrally with the carriage 42 and has a strength sufficient to support the weight of the entire carriage 42. Further, the spherical portion 42m-2 is provided below the protrusion 42m-1, and abuts on the support portion 2Wc-2 provided on the width direction connecting portion 2Wc of the apparatus frame 2 described in FIG. Is positioned relative to the apparatus frame 2 only in the Z direction, and is slidably held in the X and Y directions.

  Thus, the medium discharge side of the carriage 42 is held in such a manner that only the Z direction is restricted by the spherical portion 42m-2 with respect to the apparatus frame 2, so the medium discharge side of the carriage 42 is in the X direction, Y It can move freely with respect to the direction, rotation about the Y axis, and rotation about the Z axis. The Z direction is also restricted only by the weight of the carriage 42. When a force greater than the weight of the carriage 42 is applied from below the carriage 42, the carriage 42 is lifted from the apparatus frame 2. Will be. In order to prevent the carriage 42 from being lifted by a predetermined amount or more, the support portion provided in the width direction connecting portion 2Wc of the apparatus frame 2 is for restricting the displacement of the protrusion 42m-1 in the Z direction to a predetermined amount or less. A restricting portion 2Wc-1 is provided.

  As described above, the carriage 42 is engaged with the apparatus frame 2 only at the above-described three positions. The medium supply side is held to be rotatable about the X axis around the medium supply roller bearing 42e with respect to the apparatus frame 2 via the medium supply roller coupling portion 42d and the registration roller pair 13. On the medium discharge side, only the position in the Z direction is regulated by the medium discharge side support portion 42m. Therefore, even when an external force is applied and the apparatus frame 2 is deformed, the medium discharge of the carriage 42 with respect to the apparatus frame 2 is performed. The side is moved and rotated about the X direction, the Y direction, the Y axis, and the Z axis, so that the apparatus frame 2 is not affected by the deformation, and the carriage 42 posture and the carriage 42 with respect to the registration roller pair 13 are not affected. The posture of the platen part 30 suspended from the can always be kept constant.

Next, a description will be given of the pin 42c constituting the coupling portion with the platen portion 30 of the carriage 42.
At the four corners of the carriage 42, pins 42c are provided at positions corresponding to the platen guide holes 39a, 39b, 39c provided in the platen portion 30 shown in FIG. 5 (see FIG. 17). These pins 42c engage with platen guide holes 39a, 39b, 39c of the platen portion 30, respectively. In this engagement, since the platen guide hole 39 a and the platen guide hole 39 b are pressed against the platen part 30 by the plunger mechanism, the platen part 30 is accurately positioned with respect to the carriage 42.

  20 and 6 to 8, the pin 42c has a stepped surface 42c-1 on which the platen frame head facing surface 33a of the platen unit 30 lifted by the platen drive unit 36 abuts, and a platen guide hole 39a (39b, 39c).

  The coupling portion includes a cylindrical surface 42c-2 that contacts the concave portion 39a-1 formed in a right-angle shape, and a slit portion 42c-3 that engages with the slide hook 38 and can suspend the platen portion 30 from the carriage 42. And a chamfered portion 42c-4 as shown in FIGS. 27A and 27B in order to guide the platen 30 so as to be smoothly inserted into the platen guide hole 39a (39b, 39c). . Here, the stepped surface 42c-1 ensures a predetermined space between the platen belt 31 and the ink head row 41 even when the platen frame head facing surface 33a of the platen portion 30 abuts against this surface. Dimensions are determined.

  Next, the discharge unit 50 will be described.

  The discharge unit 50 is a mechanism that discharges the recording medium on which the image is recorded by the image recording mechanism 20. As shown in FIG. 1, the discharge unit 50 includes a discharge unit transport roller pair 51, a discharge unit discharge roller pair 52, a path switching unit 53, and a discharge tray 55. The recording medium conveyed from the platen unit 30 is conveyed by the discharge unit conveyance roller pair 51 and the discharge unit discharge roller pair 52 and discharged to the discharge tray 55.

Next, the maintenance unit 60 will be described.
As shown in FIG. 1, the maintenance unit 60 includes a plurality of maintenance units 61, a plurality of maintenance ink pans 62, a maintenance unit driving unit 63, a conveyance direction guide frame 64, four elevating guide frames 65, position detection means (not shown). )have. The plurality of maintenance units 61 are provided so as to correspond to the positions of the four ink head rows 41. Specifically, as shown in FIG. 12, the maintenance units 61 are arranged at a predetermined distance apart on the Y axis, similarly to the arrangement of the ink head rows 41.

Next, the control unit 90 will be described.
As shown in FIG. 21, the control unit 90 is constituted by a computer including a CPU, a timer, a ROM, a RAM, and the like. The control unit 90 is connected to the medium supply unit 10, the image recording mechanism 20, the discharge unit 50, the maintenance unit 60, the ink supply unit 70, and the recording medium reversing unit 80, and controls these drives.

Next, the operation of the image recording apparatus configured as described above will be described.
First, when an image is recorded by the image recording apparatus 1, image data is input to the control unit 90 via an interface (not shown). When image data is input, the control unit 90 executes image recording processing.

  Next, the control unit 90 causes the image recording apparatus 1 to retract the maintenance unit 60. When the maintenance unit 60 is retracted, it is confirmed that the rack HPSW 38-4 (see FIG. 5) of the platen unit 30 is ON (the slide hook 38-1 is in the open position with respect to the pin 42c), and then the platen drive unit motor 36d. And the platen unit 30 is raised in the direction of the arrow through the platen drive unit 36 (state shown in FIG. 22A).

  When the platen support 36b is rotated by the platen drive 36, the roller 36b-1 at the tip of the platen support 36b comes into contact with the platen drive guide 33c. When the platen support portion 36b further rotates, the platen portion 30 is lifted and raised by the roller 36b-1.

  When the platen unit 30 is raised, the upper surface thereof contacts the lower surface of the maintenance unit 60. After the contact, the roller 36b-1 rotates with the rise of the platen support portion 36b, and the platen portion 30 and the maintenance portion 60 are smoothly lifted and raised, and the 11 platen portion 30 is engaged. The tip of the pin 42c protruding from the carriage 42 comes into contact with the hole.

  Therefore, the position of the platen portion 30 and the maintenance portion 60 mounted on the platen portion 30 is corrected to the position of the engagement hole by the pin 42c, and the platen portion 30 abuts against the abutting surface to be in a state where the position in the plane direction is regulated. When further raised, the platen frame head facing surface 33a of the platen portion 30 abuts against the stepped surface 42c-1 of the pin 42c. Until the platen frame head facing surface 33a comes into contact with the stepped surface 42c-1, the position of the platen support portion 36b1 remains in a state where the stopper 36b-4a is in contact with the notch 36b-7 (ie, elastically biased and immobile). The platen support 36b rotates.

  As described above, this is set so that the set force amount of the compression spring 36b-6 becomes larger (does not shrink) with respect to the weight of the platen portion 30 and the maintenance portion 60 that compress the compression spring 36b-6, and is elastic. The stopper 36b-4a is pressed by the force to be in a stationary state.

  When the platen support portion 36b is further rotated and rises by the platen driving portion 36, the rise of the platen portion 30 is restricted by the stepped surface 42c-1 of the pin 42c of the carriage 42. For this reason, in addition to the weight of the platen part 30 and the maintenance part 60, the weight of the image recording part 40 is loaded on the platen support part 36b. As described above, when the component force applied in the longitudinal direction of the platen support portion 36b due to this load becomes larger than the set force amount, the compression spring 36b-6 of the platen support portion 36b starts to contract against the weight component force. Further, as the platen support 36b rises, the stopper 36b-4a moves away from the upper end surface of the notch 36b-7, and the platen support 36b rotates while being displaced downward.

  As described above, the gap between the roller 36b-1 provided at the tip of the platen support portion 36b and the stepped surface 42c-1 of the pin 42c of the carriage 42 is caused by component variations that occur during manufacturing. The variation occurs, but is absorbed by the sliding (downward displacement) of the roller 36b-1 due to the elasticity of the compression spring 36b-6.

  At this time, in the state where the platen driving unit 36 reaches the top dead center as shown in FIG. 1, the roller 36b-1 provided at the tip of the four platen support units 36b is lowered, so that the stopper 36b -4a is in the middle of the notch 36b-7 away from the upper end and not in contact with the lower end. Therefore, the compression spring 36b-6 is in an elastic state capable of expanding and contracting. The position where the platen driving unit 36 reaches the top dead center is the image recording position.

  Since the compression spring 36b-6 is in an elastic state in which the compression spring 36b-6 can be expanded and contracted in the middle of the position, when the platen portion 30 is lowered due to the dimensional variation of parts or the state of distortion of the frame, the roller 36b-1 moves upward. Since it is biased, the platen frame head facing surface 33a can be brought into close contact with the pin step surface 42c-1.

  Further, when the platen drive unit 36 reaches the top dead center, the position where the roller 36b-1 attached to the tip of the four platen support units 36b contacts the platen drive unit guide 33c protrudes from the carriage 42. Near the four pins 42c. That is, it is in the vicinity of the stepped surface 42c-1 of the pin 42c against which the platen frame head facing surface 33a is elastically abutted. The platen frame head facing surface 33a of the platen unit 30 abuts the stepped surface 42c-1 of the pin 42c of the carriage 42, and the platen support unit 36b lifts the carriage 42 together with the maintenance unit 60 via the platen unit 30 and the pin 42c. Act on.

  At this time, the compression spring 36b-6 of the platen drive unit 36 lifts the platen unit 30 and the maintenance unit 60 and reliably abuts against the stepped surface 42c-1 of the pin 42c of the carriage 42. As described above, the acting position of the force amount of the compression spring 36b-6 is in the vicinity of the stepped surface 42c-1 of the pin 42c of the carriage 42. Therefore, the pushing force of the compression spring 36b-6 is efficiently stepped surface 42C-1. The platen frame head facing surface 33a is brought into close contact with the stepped surface 42C-1.

  When the point of application of the compression spring push-up force is at a position away from the stepped surface 42C-1 (for example, in the middle of the two pins 42c), it acts as a force that bends the platen portion 30 like a beam. For this reason, the flatness of the platen unit 30 changes, causing the belt conveyance direction to change at the time of printing and causing a print position shift between colors. If the operating position of the compression spring 36b-6 is in the vicinity of the stepped surface 42c-1 of the pin 42c of the carriage 42, such a problem does not occur. When the pushing force of the compression spring 36b-6 is large, the carriage 42 may be lifted through the platen unit 30 and the maintenance unit 60, but the displacement restriction provided on the medium discharge side support unit 42m of the carriage 42 The upward movement of the carriage can be restricted to a predetermined amount or less by the portion 2Wc-1.

In this state where the platen unit 30 is pressed against the pin 42C by the platen drive unit 36, a space constituted by the lower surface of the platen frame head facing surface 33a and the lower surface of the slit portion 42c-3 of the pin 42c of the carriage 42. In this case, a distance that allows the slide hook 38-1 to be inserted is secured.

Next, by moving the rack member 38-2 in the direction of the arrow, the slide hook 38-1 is moved to a predetermined recording position (for example, a plain paper position) (the state shown in FIG. 22C, see FIG. 26). .
When the movement of the rack member 38-2 is completed, the platen support portion 36b is rotated, and the platen support portion 36b is rotated from the top dead center in a direction in which the platen support portion 36b is tilted. Initially, the roller 36b-1 of the platen support portion 36b of the platen drive portion 36 is pushed down without resisting the weights of the carriage 42, the maintenance portion 60, and the platen portion 30, but as the platen support portion 36b rotates. The roller 36b-1 moves until it hits the end of the long hole 36b-2 of the arm 36b-3. Up to this point, the platen unit 30 is in contact with the carriage 42. When the platen support portion 36b further rotates further, the platen portion 30 starts to descend in the direction of the arrow in the figure, and the lower surface of the platen frame head facing surface 33a of the platen portion 30 and the upper surface of the slide hook 38-1 come into contact with each other. At the same time, the lower surface of the slide hook 38-1 and the lower surface of the slit portion 42c-3 of the pin 42 come into contact (see the state shown in FIG. 22D).

If the rotation of the platen support portion 36b is further continued from this position, the platen drive portion guide 33c and the platen support portion 36b of the platen portion 30 are separated, and the platen portion 30 is separated from the carriage 42 via the pin 42c. It will be in the state suspended (refer FIG. 24).
In this state, the platen unit 30 is suspended by the carriage 42 supported by the apparatus frame 2 and is in a state of being completely disconnected from the apparatus frame 2 without being in contact with the apparatus frame 2. For this reason, even if a disturbance or the like is applied to the apparatus frame 2 and the apparatus frame 2 is deformed, the positional relationship between the platen unit 30 and the carriage 42 does not change. Further, since the carriage 42 also supports the registration roller pair 13, the positional relationship among the registration roller pair 13, the platen unit 30 and the carriage 42 does not change. In addition, since the carriage 42 supports the upper and lower rollers together with the registration roller pair 13, the cross angle formed by the axes of the upper and lower rollers is kept constant. When the cross angle changes, the medium conveyance direction changes, but by supporting both the registration roller pair 13 in this way, the cross angle does not change and the medium conveyance direction is stabilized. Therefore, the positional relationship between the recording medium conveyed by the registration roller pair 13 and the platen unit 30 and the ink head row 41 of each color held by the carriage 42 and the conveying direction vary in the X, Y, and Z directions. I don't get it.

Next, after the retraction of the maintenance unit 60 is completed and the arrangement of the platen unit 30 at the position where the recording medium can be transported is completed, the recording medium is started to be taken out.
(Removal of recording medium)
The control unit 90 turns on the clutch and drives the pickup roller 12 to rotate. The pickup roller 12 picks up the recording medium from the recording medium tray 11 and conveys the recording medium to the registration roller pair 13 along the recording medium conveyance direction.

(Alignment of recording media)
Next, the recording medium is arranged at the time of conveyance by abutting the leading end of the recording medium against the registration roller pair 13. After the position adjustment of the recording medium, the recording medium is conveyed to the area of the image recording mechanism 20 and an image recording process by the image recording mechanism 20 is performed.

(Image recording process)
In this image recording process, first, the first to third platen chambers 35 a, 35 b, and 35 c are made negative pressure by the platen chamber negative pressure generation sources 34 a of the platen unit 30. At the same time, the platen belt 31 is driven. When the recording medium is conveyed from the medium supply unit 10 to the image recording mechanism 20 (at the beginning of conveyance), the leading end of the recording medium is attracted and held on the platen belt 31 by the suction force of the first platen chamber 35a.

  For this reason, the recording medium can be prevented from floating from the platen belt 31. The recording medium held by suction is moved by the platen belt 31 at a predetermined speed along the recording medium conveyance direction. In the image recording state in which the platen unit 30 is suspended by the carriage 42, the two platen belt rollers 32 are kept substantially parallel, and the platen belt 31 that conveys the recording medium is parallel to the X and Y axes. I support it.

  Subsequently, when the leading end of the recording medium is transported to a position facing the ink head row 41, each ink head row 41 starts ejecting ink to the recording medium. Since the ink head row 41 extends over the entire width of the recording medium, an image can be recorded over the entire width with a single ejection. Along with this image recording, the platen unit 30 conveys the recording medium along the Y axis. For this reason, images are sequentially recorded in the longitudinal direction of the recording medium.

  Then, the recording medium passes through all the ink head rows 41 through all the areas, thereby completing the image recording throughout. Thereafter, when the rear end of the recording medium passes through the recording areas of all the ink heads, the image recording process is completed.

(Standby operation)
After a predetermined time has elapsed after the image recording operation is completed, or when the maintenance operation is started, it is necessary to move the platen unit 30 from the recording operation position to the standby position or the maintenance operation position.

First, the platen support part 36b is rotated, and the platen part 30 suspended from the carriage 42 is again lifted in the direction of the arrow shown (see the state shown in FIG. 22E).
When the platen support portion 36b is moved to the top dead center, the platen portion 30 again strikes the stepped portion 42c-1 of the pin 42c, and the lower surface of the platen frame head facing surface 33a, the lower surface of the slit portion 42c-3 of the pin 42c, The space formed by is sufficient to pull out the slide hook 38-1 in the direction of the arrow shown in the drawing (see the states shown in FIGS. 23 and 22 (f)).

  Here, the rack drive motor is rotated, and the slide hook 38-1 is pulled out (see the states shown in FIGS. 26 and 22 (g)). Thereafter, the platen support part 36b is rotated in the reverse direction from the top dead center, the tip is lowered, and the platen part 30 is lowered in the direction shown by the arrow (see the state shown in FIG. 22 (h)). Even when a jam error occurs, the processing space can be secured by separating the platen unit 30 from the image recording unit 40 by the same operation.

  Further, when the maintenance operation is performed, the platen unit 30 is similarly placed on the roller 36b-1 of the platen support unit 36b from the recording operation position where the platen unit 30 is suspended by the carriage 42. Thereafter, the maintenance unit 60 is moved to a retracted position in which the upper surface of the maintenance unit 61 provided in the maintenance unit 60 is separated in the vertical direction from the ink discharge nozzle surface (not shown) provided on the lower surface of the ink head unit 43. Lower (see the state shown in FIG. 13). This lowering operation is performed by the platen driving unit 36 as described above. This retracted position is controlled by a Z-axis retracted position sensor 68d.

  After the maintenance unit 60 is lowered to a predetermined position, the maintenance unit 61 is moved below the ink head unit 43 by the maintenance unit driving unit 63. After each maintenance unit 61 has moved to a position facing each ink head unit 43, the maintenance unit 61 is raised to a maintenance position where it abuts against the ink ejection surface of the ink head unit 43 by the platen drive unit 36 (state shown in FIG. 11). reference). The maintenance position is controlled by the Z-axis suction position sensor 68c.

  The maintenance unit 61 is pivotally supported by a mechanism (not shown) so as to be swingable up and down with respect to the maintenance unit 60. Further, it is elastically biased upward by a pressing spring (not shown), and upward displacement is restricted by a stopper (not shown).

  Thus, when the maintenance unit 61 is brought into contact with the ink discharge surface of the ink head unit 43 at the maintenance position, the pressing spring is contracted. With the amount of spring force corresponding to the contraction, the ink can be elastically pressed against the ink ejection surface. Maintenance operation is performed in this state. When the maintenance is completed, the maintenance unit 60 is lowered again to the retracted position, and then the maintenance unit 61 is moved to the retracted position provided in the lateral direction of the ink head unit 43. When this retracting operation is completed, the platen unit 30 returns to a state where it can move up and down to the image recording operation position.

  The elasticity of the pressing spring is used when the maintenance operation is performed, if the maintenance units 61 are not uniformly adhered to all the ink head units 61, the maintenance effect is uneven. For example, if the maintenance unit 60 is tilted and is not in close contact with the ink head unit 43 and there is a gap, no matter how many times the ink head unit 43 is maintained, the ink on the nozzle opening and the nozzle surface, etc. The rest does not return to normal.

  At the maintenance position, the maintenance unit 60 overlaps the platen unit 30 and is supported by the arm 36b of the platen drive unit 36. The roller 36b-1 of the platen support 36b is provided with a compression spring 36b-6 for elastically biasing. However, the amount of compression spring force is set so that the stopper described above is pressed against the upper end of the notch of the bracket guide 36b-5 and the compression spring 36b-6 does not expand and contract (elastically biased and immobile state). . Therefore, at the maintenance position, the compression spring 36b-6 does not expand and contract, and the height displacement of the roller 36b-1 does not occur.

  The maintenance unit 61 supported by the roller 36b-1 via the platen unit 30 is horizontal at a certain height, and is parallel to the ink ejection surface of the ink head unit 43. With this configuration, the adhesion degree of the maintenance unit 61 to all the ink head units 43 can be made uniform. Therefore, the maintenance operation for all the ink head units 43 can be reliably performed.

  Further, on the platen frame head facing surface 33a side of the platen frame 33, platen guide holes 39a, 39b, and 39c for alignment with the image recording unit 40 are formed in a region (non-platen region) that does not face the platen belt 31. Provided (see FIG. 5). In the present embodiment, platen guide holes 39a and 39c on the upstream front side and rear side in the recording medium conveyance direction, and platen guide holes 39b and 39c on the downstream front side and rear side, respectively. A total of four are provided.

  With the configuration described above, since the separation / proximity operation of the maintenance unit 60 with respect to the ink head unit 43 can be performed using the lifting mechanism of the platen unit 30, the mechanism can be simplified and the apparatus can be downsized. . Further, since the control can be simplified, the position of the maintenance unit 60 with respect to the ink head unit 43 can be easily controlled.

  Also, in the mechanism for raising and lowering the platen unit 30 via the elastic means, since the elastic member is always set to a predetermined displacement amount during maintenance, the platen unit 30 supported by the elevation mechanism is all The maintenance unit 60 can be held in parallel to the ink head unit 43, and the maintenance operation can be performed reliably.

  Further, when the platen portion 30 is applied to the pin 42C provided on the carriage 42, the application is performed in the vicinity of the pin 42C, so that the flatness of the platen portion 30 is not deformed and the application surface is not affected. It can be reliably applied. The color superposition between the colors is always stable, and the ink head unit 43 can be kept in the best state by the stable maintenance, so that a high-quality image recording apparatus can be realized.

Next, a second embodiment will be described.
FIGS. 28A and 28B are diagrams illustrating a schematic configuration of a platen unit in the image recording apparatus according to the second embodiment. FIG. 28 (a) shows a state of a maintenance position where the elastic mechanism is not affected by the elastic force and the position is rigidly determined. FIG. 28 (b) shows the state of the carriage pin 42c while the elastic force of the elastic mechanism is acting. The state where it abutted against the stepped surface 42c-1 is shown. In FIG. 28B, the height of the platen unit 30 (the interval between the carriage 42 and the platen unit 30) indicates the same position in the image recording state. In the present embodiment, the shape of the platen drive section guide 33c of the platen frame 33 is different from the first embodiment described above. Other components are the same as those in the first embodiment.

  In the above-described first embodiment, the compression spring is provided so that the roller 36b-1 provided at the tip of the platen support 36b is elastically movable. On the other hand, the roller 36b-1 at the tip of the platen support portion 36 of the present embodiment is not provided with a compression spring and does not move elastically with respect to the platen support portion b36. In the present embodiment, a lever 101 that is elastically movable is provided on a platen driving section guide 33c in which the roller 36b-1 of the platen support section 36b contacts and moves at the lower part of the platen section 30.

  In this platen drive section guide 33c, the portion of the platen support section 36b at the maintenance position where the roller abuts is in contact with a non-elastic region 103 made of a rigid body (metal or the like) having no elasticity, and at least the platen support section at the image recording position. The portion with which the roller 36b-1 at the tip of 36b abuts is composed of two regions, an elastic region 104 formed of an elastically movable lever 101. Note that the inelastic region 103 of the present embodiment is the same as the elastically biased immobile state in the first embodiment, and the elastic region 104 is the same as the elastically movable state in the first embodiment.

  The lever 101 is pivotally supported at one end by a fulcrum 102 provided on the platen frame 33 so as to be rotatable. A compression spring 100 for elastically biasing the other end of the lever 101 downward is provided. The lever 101 urged by the amount of force (elastic force) by the compression spring 100 hits the stopper 105 provided on the platen frame 33 and holds the position protruding downward (θ) from the surface of the inelastic region 103. . The amount of force of the compression spring in the state where it hits the stopper 105 is set in the same manner as in the first embodiment. The compression spring 100 and the lever 101 constitute an elastic member (or elastic means) in this embodiment.

  The outer periphery of the lever 101 around the fulcrum part 102 is formed in an arc shape centered on the fulcrum part 102, and the radius is set to be equal to the distance from the fulcrum part 102 to the platen drive part guide 33c. Has been. With this configuration, when the roller 36b-1 moves between the inelastic region 103 and the elastic region 104, the roller 36b-1 can move smoothly without a step.

The operation of the second embodiment will be described.
First, in order to lift the platen unit 30, when the platen support unit 36b is rotated to start up, the roller 36b-1 first moves while contacting the inelastic region 103 of the platen drive unit guide 33c. In the maintenance operation position shown in FIG. 28A, since the contact position of the roller 36b-1 is still in the inelastic region 103, the height of the platen portion 30 is not displaced by the elastic member.

  Subsequently, the roller 36b-1 moves and enters the elastic region 104 shown in FIG. When entering the elastic region 104, the roller 36b-1 moves while contacting the lever 101 urged by the compression spring 100. The platen frame head facing surface 33a further rises and abuts against the stepped surface 42c-1 of the pin 42c. After that, the lever 101 cannot be held stationary by the amount of force (elastic force) in the compression spring 100. Compression starts. By this compression, the lever 101 is displaced, and the platen frame head facing surface 33a is pressed against the stepped surface 42c-1 to make sure that the platen frame head facing surface 33a is in close contact, and also absorbs variations in the abutting position due to component variations.

  As described above, in the second embodiment, the platen driving unit guide 33c is divided into the non-elastic urging region 103 that is rigidly abutted and the elastic urging region 104 that abuts while elastically urging, thereby maintaining the operation. The height position of the maintenance unit 61 with respect to the ink head unit 43 becomes uniform at the position where the ink head unit 43 is performed.

  In the embodiment, the elastic biasing mechanism including the lever 101 and the compression spring 100 is provided in the platen unit 30. However, the platen unit 30 and the platen driving unit 36 are combined by combining the first and second embodiments. Both may be provided with an elastic urging mechanism.

Next, a first modification according to the second embodiment will be described.
In the first modification shown in FIG. 29, instead of the compression spring used for the elastic member (or elastic means) in the second embodiment, the torsion coil spring 111 is fitted to the fulcrum portion 102 to One end is fixed by a spring stopper portion 112 disposed on the platen frame 33, and the other end of the torsion coil spring 111 is fixed to the slit 101 a of the lever 101. The amount of force of the torsion coil spring 111 is assumed to have the same amount of force as in the first and second embodiments described above. Accordingly, the operation is the same as that of the second embodiment.

  According to the 1st modification, it has an effect equivalent to 2nd Embodiment. Furthermore, the torsion coil spring can be made smaller and lighter than the pressure spring.

Next, a second modification according to the second embodiment will be described.
In the second modification shown in FIG. 30, a leaf spring 121 is fitted into the lever 101 in place of the compression spring used for the elastic member (or elastic means) in the second embodiment, and the fulcrum portion 102 is bent as a fulcrum. Thus, it is the structure fixed with the spring stopper part 122. FIG.

  According to the 2nd modification, it has an effect equivalent to 2nd Embodiment. Further, the leaf spring can be made smaller and lighter than the pressure spring and the torsion coil spring.

  In the first and second embodiments and the first and second modifications described above, the elastic member is exemplified by a compression spring (coil spring: spring), a torsion coil spring, and a leaf spring. However, it can also be implemented using a rubber material and a resin material having the same elastic force. In the first and second embodiments, the direction in which the elastic member is urged is exemplified by the displacement in the direction in which the interval between the image recording mechanism 20 and the platen unit 30 is reduced, that is, the direction in which the spring is contracted. . Of course, the present invention is not limited to the reduction, and the stopper position can be changed so that the elastic force acts in the extending direction.

In addition, this invention is not limited to each embodiment mentioned above, In the implementation stage, it can change variously in the range which does not change the summary.
Furthermore, each embodiment described above includes inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if several constituent requirements are deleted from all the constituent requirements shown in the embodiment, if the above-mentioned problem can be solved and the effect presented in the section of the invention effect can be obtained, this constituent requirement is The deleted configuration can be extracted as an invention.

1 is a diagram illustrating a schematic configuration of an image recording apparatus according to a first embodiment of the present invention. It is a figure which shows schematic structure of the apparatus frame which concerns on 1st Embodiment. It is a figure which shows schematic structure of the platen part which concerns on 1st Embodiment. It is a figure which shows schematic structure of the platen part positioning mechanism which concerns on 1st Embodiment. It is a figure which shows schematic structure of the platen part positioning mechanism which concerns on 1st Embodiment. It is a figure which shows schematic structure of the platen guide hole which concerns on 1st Embodiment. It is a figure which shows schematic structure of the platen guide hole and pin which concern on 1st Embodiment. It is a figure which shows schematic structure of the platen drive part which concerns on 1st Embodiment. It is a figure which shows schematic structure of the platen support part which concerns on 1st Embodiment. It is a figure which shows schematic structure of the platen support part which concerns on 1st Embodiment. FIG. 5 is a perspective view showing a state where the maintenance unit according to the first embodiment is placed on the platen unit and faces the image recording mechanism to perform a maintenance operation. It is a front view which shows the state which the maintenance part which concerns on 1st Embodiment which concerns on 1st Embodiment is mounted in a platen part, opposes an image recording mechanism, and performs maintenance operation | movement. It is a front view which shows the state which lowered | hung the maintenance part which concerns on 1st Embodiment with respect to the image recording mechanism. It is a figure for demonstrating the shrinkage | contraction of the compression spring which concerns on 1st Embodiment. It is a figure which shows schematic structure of the rack mechanism which concerns on 1st Embodiment. It is a figure which shows schematic structure of the slide hook of the rack mechanism which concerns on 1st Embodiment. FIG. 3 is a diagram illustrating a schematic configuration of a medium supply roller connecting portion of the carriage according to the first embodiment. FIG. 3 is a diagram illustrating a schematic configuration of a medium discharge side support portion of the carriage according to the first embodiment. It is a figure which shows schematic structure of the carriage which concerns on 1st Embodiment. It is a figure which shows schematic structure of the pin which concerns on 1st Embodiment. It is a block block diagram for demonstrating the control part which concerns on 1st Embodiment. It is a figure for demonstrating the operation state of the pin of 1st Embodiment. It is a figure for demonstrating the operation state of the carriage and platen part of 1st Embodiment. It is a figure for demonstrating the operation state of the carriage and platen part of 1st Embodiment. It is a figure for demonstrating the operation state of the carriage and platen part of 1st Embodiment. It is a figure for demonstrating the operation state of the carriage and platen part of 1st Embodiment. It is a figure which shows schematic structure of the pin which concerns on 1st Embodiment. It is a figure which shows schematic structure of the platen part of the image recording apparatus concerning the 2nd Embodiment of this invention. It is a figure which shows schematic structure of the 1st modification based on 2nd Embodiment. It is a figure which shows schematic structure of the 2nd modification concerning 2nd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image recording apparatus, 2 ... Apparatus frame, 2P ... Base plate, 2Fa, 2Fb ... Front side wall, 2Ba, 2Bb ... L-shaped side wall, 2Wa-2Wd ... Width direction connection part, 2Wc-1 ... Displacement regulation part, 2Wc- 2 ... support part, 2La-2Ld ... longitudinal direction connection part, 2Fc, 2Fd ... member support part, 2Ha. 2Hb ... hole, 10 ... medium supply unit, 11 ... recording medium tray, 12 ... pickup roller pair, 13 ... registration roller pair, 13a ... drive roller, 13b ... driven roller, 13c ... nip spring, 14a ... pickup sensor, 14b DESCRIPTION OF SYMBOLS ... Registration sensor, 20 ... Image recording mechanism, 22a-1 ... Electromagnet, 22a-2 ... Positioning member, 22a-3 ... Power supply, 22a-4 ... Suction plate, 22b-1 ... Female screw part, 22b-2 ... Male screw part, 22b-3 ... Screw motor, 22c-1 ... Hook, 22c-2 ... Positioning member, 22c-3 ... Lock pin, 22d-1 ... Manual lever, 22d-2 ... Positioning member, 22d-3 ... Rotating shaft, 22d-4 ... Hook part, 22d-5 ... Handle part, 30 ... Platen part, 31a ... Suction hole, 31 ... Platen belt, 32 ... Platen belt roller 32a ... belt roller drive motor, 32b ... roller encoder, 33 ... platen frame, 33a ... platen frame head facing surface, 33c ... platen drive section guide, 33d ... groove, 33e ... facing surface hole, 34 ... platen suction section, 34a Platen chamber negative pressure source 35a to 35c Platen chamber 36 Platen drive unit 36a Platen drive shaft 36b Platen support unit 36c Platen drive belt 36b-1 Roller 36b 2 ... long hole, 36b-3 ... arm, 36b-4 ... bracket, 36b-5 ... bracket guide, 36b-6 ... compression spring, 37 ... image width detection means, 38 ... rack mechanism, 38-1 ... slide hook, 38-2 ... Rack member, 38-3 ... Rack drive gear, 38-4 ... Rack HPSW, 38-5 ... La 39a-39c ... Platen guide hole, 39a-1 ... Recess, 39a-2 ... Parallel pin, 39a-3 ... Spring, 40 ... Image recording part, 41 ... Ink head row, 42 ... Carriage, 42a ... head Mounting portion 42b Carriage hole 42c Pin 42c-1 Stepped surface 42c-2 Cylindrical surface 42c-3 Slit portion 42c-4 Chamfered portion 42d Media supply roller connecting portion 42e ... medium supply roller bearing fitting part, 42f ... elongated hole, 42m ... medium discharge side support part, 42m-1 ... projection part, 42m-2 ... spherical part, 43 ... ink head unit, 49 ... head cooling part, 49a ... Cooling fan, 50 ... discharge section, 51 ... discharge section transport roller pair, 52 ... discharge section discharge roller pair, 53 ... path switching section, 54 ... discharge auxiliary section, 54b ... wing, 55 ... discharge tray, 60 ... maintenance 61, maintenance unit, 62 ... maintenance ink pan, 63 ... maintenance unit drive unit, 63a ... suction unit drive mechanism, 64 ... transport direction guide frame, 65 ... lift guide frame, 65B ... slide mechanism, 66 ... suction pump 68a ... Y-axis suction position sensor, 68b ... Y-axis withdrawal position sensor, 68c ... Z-axis suction position sensor, 68d ... Z-axis withdrawal position sensor, 68e ... X-axis home position sensor, 70 ... Ink. Supply unit, 71b ... distributor valve, 71c ... bubble detection unit, 72e ... pressurization valve, 72g ... atmospheric release valve, 72h ... connection tube valve, 72ka ... liquid level detection sensor, 73Ab ... open / close detection sensor, 73Gd ... lock plate drive Means, 731 ... wireless reading device, 75b ... pressure sensor, 76 ... pressure pump, 80 ... recording medium reversal , 81c, a conveyance path sensor, 82b, a conveyance path sensor, 82a, a reverse belt unit, 83d, an end detection sensor, 83b, a reverse roller pair, 84a, a re-medium supply roller pair, 90, a control section, 91, an input section, 92 ... Output section, 138-1 ... Wedge slide, 100 ... Compression spring, 101 ... Lever, 102 ... Support point, 103 ... Non-elastic biasing area, 104 ... Elastic biasing area, 111 ... Torsion coil spring, 112,122 ... Spring stopper Part, 121 .. leaf spring.

Claims (6)

An image recording unit capable of recording an image over the entire recording width of the recording medium;
A maintenance unit that acts on the ink discharge port of the image recording unit to recover ink discharge;
A recording medium transport unit that is disposed facing the image recording unit, holds the recording medium, and transports the recording medium in a direction perpendicular to the width direction of the recording medium;
An interval variable mechanism that abuts the recording medium conveyance unit, supports the recording medium conveyance unit and the maintenance unit so as to be movable up and down, and varies an interval between the recording medium conveyance unit and the maintenance unit with respect to the image recording unit;
Provided in the interval variable mechanism, and at least during the maintenance operation by the maintenance unit, urges the interval in a direction to reduce the interval, supports the maintenance unit in an immovable state by urging elastic force, and the recording medium transport unit An elastic biasing mechanism that supports the recording medium transport unit in a movable state by biasing an elastic force at a position closer to the image recording unit than a position during the maintenance operation;
An image recording apparatus comprising: The elastic biasing mechanism is
An elastic member having an elastic force that immobilizes the interval variable mechanism when a load is applied by the recording medium conveyance unit and the maintenance unit;
A stopper member formed in the interval variable mechanism and moving in conjunction with the displacement of the elastic member;
A locking member which is provided in the interval variable mechanism and engages with the stopper member to define a variable range of displacement of the elastic member;
The stopper member is pressed against and maintained at the variable range end of the locking member by the elastic force of the elastic member in the non-moving state, and the recording medium transport unit is pressed against the image recording unit in the movable state. The image recording apparatus according to claim 1, wherein the distance varying mechanism is made movable by displacing the gap. An image recording unit capable of recording an image over the entire recording width of the recording medium;
A maintenance unit that acts on the ink discharge port of the image recording unit to recover ink discharge;
A recording medium transport unit that is disposed facing the image recording unit, holds the recording medium, and transports the recording medium in a direction perpendicular to the width direction of the recording medium;
An interval variable mechanism that abuts on the recording medium conveyance unit and varies an interval between the image recording unit and the image recording medium conveyance unit and the maintenance unit;
An elastic biasing mechanism that is provided in a part of the abutting portion of the recording medium conveying unit and elastically supports the recording medium conveying unit with respect to the interval variable mechanism;
Have
The variable interval mechanism inelastically supports the recording medium conveyance unit during the maintenance operation by the maintenance unit, and the recording medium conveyance unit is closer to the image recording unit than the position during the maintenance operation. An image recording apparatus characterized by elastically supporting the recording medium transport unit. The elastic biasing mechanism is
An elastic member;
A locking member that is formed in the recording medium transport unit and moves in conjunction with the displacement of the elastic member;
The image recording apparatus according to claim 3, further comprising: a stopper member that is provided in the recording medium conveyance unit and engages with the locking member to prevent displacement of the elastic member. .   4. The image recording apparatus according to claim 1, wherein an urging direction of the elastic force by the elastic urging mechanism is a direction in which the interval is reduced.   4. The image recording apparatus according to claim 1, wherein the maintenance unit moves closer to and away from the image recording unit in conjunction with the elevation of the recording medium transport unit.

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