JPWO2019044031A1 - Nozzle position adjustment device for recording head - Google Patents

Abstract

A plurality of head modules that have a nozzle surface composed of a plurality of nozzles for ejecting liquid droplets on a recording medium to be conveyed and are arranged side by side in a direction intersecting the conveyance direction of the recording medium to form a recording head (20). (24), a top plate (70) extending in the intersecting direction, and a support plate (72) suspended from the top plate (70), and a support member (50) to which the head module (24) is attached. ) And a nozzle position adjusting device (90) of the recording head (20), the support plate (72) positions the position in the direction along the transport direction provided in the head module (24). The top plate (70) has a reference surface (52) with which the positioning member (36) abuts, and the top plate (70) has a position in the intersecting direction of the head modules (24) and a position in the rotational direction about the normal direction of the nozzle surface. It has an adjusting mechanism (100) for adjusting.

Description

  The present disclosure relates to a nozzle position adjustment device for a recording head.

  Recording in which a plurality of head modules having a nozzle surface composed of a plurality of nozzles for ejecting liquid droplets onto a conveyed recording medium are arranged in a staggered manner on a support member extending in a direction orthogonal to the conveying direction of the recording medium. In the head, a position adjusting mechanism for adjusting the position of the head module with respect to the supporting member in the three-dimensional direction is provided for each head module, which has been proposed in the past (for example, Japanese Patent Laid-Open No. 2009-262540 or (See Japanese Patent Laid-Open No. 2015-107656).

  However, when the position adjusting mechanism of the head module with respect to the supporting member is provided for each head module, a space for providing the position adjusting mechanism is provided mainly in at least one of the upstream side and the downstream side of the recording medium in the transport direction. It becomes necessary, and in a plurality of recording heads arranged for each color, space saving on the upstream side and the downstream side of the recording medium in the transport direction may be hindered.

  Therefore, according to the present disclosure, in a recording head provided with a mechanism for adjusting the position of the head module with respect to the support member, nozzle position adjustment of the recording head that can realize space saving on the upstream side and the downstream side in the transport direction of the recording medium. The purpose is to obtain the device.

  In order to achieve the above object, a nozzle position adjusting device for a recording head according to an embodiment of the present disclosure has a nozzle surface that includes a plurality of nozzles that eject droplets onto a recording medium that is conveyed, The head module has a plurality of head modules that are arranged side by side in the intersecting direction to form a recording head, a top plate that extends in the intersecting direction, and a support plate that is suspended from the top plate. The support plate has a reference surface with which a positioning member for positioning the position in the transport direction provided on the head module abuts, and the top plate intersects with the head module. It has an adjusting mechanism for adjusting the position in the direction and the position in the rotational direction about the normal to the nozzle surface.

  According to the present disclosure, in a recording head provided with a mechanism for adjusting the position of the head module with respect to the support member, it is possible to realize space saving on the upstream side and the downstream side in the recording medium conveyance direction.

1 is a side view showing a schematic configuration of an inkjet recording apparatus according to this embodiment. FIG. 4 is a bottom view showing the nozzle surface of the bar head according to the present embodiment. It is a front view showing a schematic structure of a bar head concerning this embodiment. It is a side view which shows the head module which comprises the bar head which concerns on this embodiment. It is a side view which shows the base frame which comprises the bar head which concerns on this embodiment. It is a front view showing a process of attaching a head module to a base frame concerning this embodiment. It is a side view showing a process of attaching a head module to a base frame concerning this embodiment. It is a side view showing a state where a head module is attached to a base frame according to the present embodiment. It is a perspective view which shows the position adjusting mechanism of the bar head which concerns on this embodiment typically from a back surface. It is a perspective view which shows typically the position adjustment mechanism of the bar head which concerns on this embodiment from the front. It is a side view which shows the modification of the base frame which comprises the bar head which concerns on this embodiment.

  Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the drawings. In the following, an arrow X indicates a direction orthogonal (intersecting) to the conveying direction of the paper P as a recording medium. The arrow X direction is also the arrangement direction of the nozzles N formed on the nozzle surface 22 of the bar head 20 as a recording head (the direction of the nozzle row). A direction along the conveyance direction of the paper P (direction parallel to the nozzle surface 22 and orthogonal to the direction of the nozzle row) is indicated by an arrow Y, and a height direction orthogonal to the arrow X and the arrow Y is indicated by an arrow Z. Show. Further, the conveyance direction of the paper P may be simply referred to as “conveyance direction”.

<Schematic configuration of inkjet recording device>
First, a schematic configuration of the inkjet recording device 10 will be described. As shown in FIG. 1, the inkjet recording apparatus 10 is a single-pass type line printer that forms an image on a recording surface of a sheet P, and includes a conveying drum 12, bar heads 20K, 20C, 20M, 20Y, and an inline sensor 15. And so on.

  Two grippers 14 for gripping the leading edge of the paper P are provided at positions facing each other with the rotation axis sandwiched in the transport surface (peripheral surface) of the transport drum 12 arranged with the arrow X direction as the axial direction. There is. A large number of suction holes (not shown) are formed on the transfer surface of the transfer drum 12.

  Therefore, the paper P introduced from the paper supply unit 16 is gripped by the gripper 14, is wound around the transport surface of the rotating transport drum 12, and is sucked from the suction holes, so that the transport P is transported. It is designed to be held by suction on the surface. Then, the transport drum 12 is configured to transport the suction-held paper P in the transport direction, which is the rotation direction of the transport drum 12.

  The four bar heads 20K, 20C, 20M, 20Y are arranged in order from the upstream side at a predetermined interval in the transport direction of the transport drum 12. The bar heads 20K, 20C, 20M, and 20Y have nozzle surfaces 22K, 22C, 22M, and 22Y facing the transport drum 12, respectively. A plurality of nozzles N (see FIG. 2) for ejecting black ink droplets, cyan ink droplets, magenta ink droplets, and yellow ink droplets are formed on the nozzle surface 22K, 22C, 22M, and 22Y, respectively. It is formed over the entire width of P (X direction).

  Further, the bar heads 20K, 20C, 20M, and 20Y have tangential lines at positions where the nozzle surfaces 22K, 22C, 22M, and 22Y face the nozzle surfaces 22K, 22C, 22M, and 22Y of the transport surface of the transport drum 12. It is held so that it is parallel to the direction. Further, a control unit (not shown) that controls the ink jet recording apparatus 10 controls the bar heads 20K, 20C, 20M, and 20Y to eject ink droplets from each nozzle N. As a result, an image is formed on the recording surface of the paper P that is transported by the transport drum 12.

  Further, an in-line sensor 15 is arranged on the downstream side of the four bar heads 20K, 20C, 20M and 20Y in the paper transport direction of the transport drum 12. The in-line sensor 15 is configured to read an image recorded on the recording surface of the paper P conveyed by the conveying drum 12 and convert the image into image data. Then, the paper P from which the image on the recording surface has been read is transported by the transport drum 12 and discharged from the paper discharge unit 18.

<Structure of bar head>
Next, the structure of the bar head 20 will be described. Since the bar heads 20K, 20C, 20M, and 20Y have the same configuration, the bar head 20 will be described here.

  As shown in FIGS. 2 to 5, the bar head 20 is configured by connecting a plurality of head modules 24 in one row. The head modules 24 have the same structure, and are mounted in a row on a base frame 50 as a supporting member to form one bar head 20. Therefore, the configurations of the head module 24 and the base frame 50 will be described below.

[Structure of head module]
The head module 24 is a short head, and is capable of recording an image of a predetermined print width by itself. Then, by connecting a plurality of head modules 24 along the direction of the nozzle row (the direction orthogonal to the transport direction of the paper P), one long head is configured.

  The head module 24 includes an inkjet head 26 that ejects ink droplets, and a bracket 30 that attaches the inkjet head 26 to the base frame 50. The inkjet head 26 is mainly composed of a head main body 28 and an electrical equipment piping 27.

  The head main body 28 has a rectangular plate shape and has the nozzle surface 22 on the lower surface portion. The nozzle surface 22 has a band-shaped nozzle forming region 22A in the center. The nozzle formation region 22A has a constant width and is formed along the X direction. The nozzle N is formed in the nozzle forming area 22A.

  Here, in the inkjet head 26, as shown in FIG. 2, the nozzles N are arranged in a two-dimensional matrix. Specifically, the nozzles N are arranged at a constant pitch along the X direction, and are also arranged at a constant pitch along a direction inclined by a predetermined angle with respect to the X direction.

  By arranging the nozzles N in this way, it is possible to reduce the substantial interval between the nozzles N projected in the X direction. The nozzles N may be arranged in a line along the X direction. Further, as shown in FIG. 4, the electrical equipment piping portion 27 is an assembly of piping, a circuit board, and the like, and is provided above the head main body portion 28.

  As shown in FIGS. 3 and 4, the bracket 30 is formed in an L shape including a horizontal portion 32 and a vertical portion 34. The horizontal portion 32 functions as a mounting portion for the inkjet head 26, and the vertical portion 34 functions as a mounting portion for the base frame 50. The horizontal portion 32 is formed with an opening 32A (see FIG. 7) through which the electrical equipment piping portion 27 of the inkjet head 26 passes.

  The horizontal portion 32 has a rectangular plate shape, and is formed in a shape (rectangular shape) substantially the same as the outer shape of the head main body portion 28 of the inkjet head 26. Further, the inkjet head 26 is configured such that the head main body portion 28 is attached to the lower surface portion of the horizontal portion 32. The vertical portion 34 also has a plate-like plate shape, is disposed perpendicular to the horizontal portion 32, and is joined to one end portion on the upper surface of the horizontal portion 32 to be integrated with the horizontal portion 32.

  The vertical portion 34 has a vertical portion main body 34A formed to have substantially the same width as the horizontal portion 32, a pair of first overhang portions 34B formed to extend from both sides of the vertical portion main body 34A in the X direction, and a pair of And a pair of second overhanging portions 34C formed by further overhanging in the X direction from the first overhanging portions 34B.

  Further, in the vertical portion 34, a head module Y-direction positioning unit that serves as a reference for Y-direction positioning when the head module 24 is attached to the base frame 50, and a head module Z-direction positioning unit that serves as a Z-direction positioning reference. And a part of the X-direction mounting position adjusting means for finely adjusting the mounting position in the X direction.

  As shown in FIGS. 2 to 4, the head module Y-direction positioning means constitutes two head module Y-direction fixed contact members 36 that constitute the head module Y-direction positioning member, and also constitutes the head module Y-direction positioning member. It is composed of one head module Y direction movable contact member 38. The straight line connecting the centers of the two head module Y-direction fixed contact members 36 is parallel to the X-direction.

  The two head module Y-direction fixed contact members 36 are formed of rigid spheres (spheres having rigidity), and are provided on the second overhanging portion 34C of the vertical portion 34. More specifically, the head module Y-direction fixed contact member 36 has a reduced diameter formed on the inner surface (the surface facing the base frame 50 when the head module 24 is attached to the base frame 50) of the second protrusion 34C. It is provided in a state in which it is inserted into the hole shown and is biased by an unillustrated coil spring from the inner surface of the second overhanging portion 34C so that a part thereof protrudes by a predetermined amount.

  On the other hand, the head module Y-direction movable contact member 38 is also formed of a rigid sphere (a sphere having rigidity) and is provided in the vertical portion main body 34A of the vertical portion 34. Specifically, the head module Y-direction movable contact member 38 is provided in the vertical portion main body 34A by being inserted into the head module Y-direction movable contact member insertion hole 39 formed in the vertical portion main body 34A.

  The head module Y direction movable contact member insertion hole 39 is formed along the Y direction and penetrates from the outer surface to the inner surface of the vertical portion main body 34A. Therefore, the head module Y-direction movable contact member 38 is provided so as to be inserted into the head module Y-direction movable contact member insertion hole 39 and projectable from the inner surface of the vertical portion main body 34A. The head module Y direction movable contact member insertion hole 39 is also formed with a reduced diameter on the inner surface side of the vertical portion main body 34A so that the head module Y direction movable contact member 38 does not fall off.

  Further, the head module Y direction movable contact member insertion hole 39 is constituted by a screw hole, and the head module Y direction movable contact member position adjusting screw 40 is screwed therein. The head module Y-direction movable contact member position adjusting screw 40 is configured by a so-called grub screw (screw whose head is the same size as the screw portion). By adjusting the screwing amount of the head module Y-direction movable contact member position adjusting screw 40, the protrusion amount of the head module Y-direction movable contact member 38 from the inner surface of the vertical portion main body 34A is adjusted. ..

  As will be described later, the head module Y-direction fixed contact member 36 and the head module Y-direction movable contact member 38 are provided on the base frame 50 side when the head module 24 is attached to the base frame 50. The direction positioning member 52 and the movable contact base frame Y direction positioning member 54 (see FIG. 6) are brought into contact with each other. As a result, the head module 24 is positioned in the Y direction with respect to the base frame 50.

  The head module Z-direction positioning means includes a pair of head module Z-direction contact members 42 that form a head module Z-direction positioning member. The pair of head module Z-direction contact members 42 are provided on the first overhanging portion 34B of the vertical portion 34. The head module Z-direction contact member 42 is also formed of a rigid sphere (a sphere having rigidity).

  The head module Z-direction contact member 42 is provided in the first overhang portion 34B by being inserted into the head module Z-direction contact member insertion hole 44 formed in the first overhang portion 34B. The head module Z direction contact member insertion hole 44 is formed along the Z direction and penetrates from the lower surface of the first overhanging portion 34B toward the upper surface thereof.

  Therefore, the head module Z-direction contact member 42 is inserted in the head module Z-direction contact member insertion hole 44, and a part of the head module Z-direction contact member 42 is provided so as to project from the upper surface of the first projecting portion 34B. The head module Z-direction contact member insertion hole 44 is formed with a reduced diameter on the upper surface side of the first projecting portion 34B so that the head module Z-direction contact member 42 does not fall off.

  Further, the head module Z-direction contact member insertion hole 44 is constituted by a screw hole, and the head module Z-direction contact member position adjusting screw 45 is screwed therein. The head module Z-direction contact member position adjusting screw 45 is composed of a so-called imet screw. By adjusting the screwing amount of the head module Z-direction contact member position adjusting screw 45, the protrusion amount of the head module Z-direction contact member 42 from the upper surface of the first projecting portion 34B is adjusted. ..

  As will be described later, the head module Z-direction contact member 42 comes into contact with the base frame Z-direction contact member 56 provided on the base frame 50 side when the head module 24 is attached to the base frame 50. .. As a result, the head module 24 is positioned in the Z direction with respect to the base frame 50.

  As shown in FIGS. 3 and 4, the X-direction mounting position adjusting means mainly includes an eccentric roller 46 as a first eccentric cam, a plunger 48 functioning as an X-direction biasing means, and an X-direction positioning reference pin 58. It consists of and. The eccentric roller 46 and the plunger 48 are provided on the head module 24, and the X-direction positioning reference pin 58 is provided on the base frame 50.

  The eccentric roller 46 is provided at one end of the shaft portion 46A, and is attached to the vertical portion main body 34A by inserting the shaft portion 46A into the eccentric roller attachment hole 35. A helical gear (worm wheel) 47 is provided at the other end of the shaft portion 46A. The eccentric roller mounting hole 35 is a through hole penetrating from the outer surface side to the inner surface side of the vertical portion main body 34A, and the shaft portion 46A is formed in a cylindrical shape parallel to the Y direction.

  The shaft portion 46A of the eccentric roller 46, which is inserted into the eccentric roller mounting hole 35, functions as a transmission shaft (rotation shaft) for transmitting the rotational driving force from the helical gear 47, and at the same time with respect to the eccentric roller 46. It is connected eccentrically. That is, the eccentric roller 46 is eccentrically rotated with respect to the shaft center of the shaft portion 46A. A screw gear 102 described later (see FIG. 3) is engaged with the helical gear 47.

  The plunger 48 is arranged along the X direction on the inner surface side of the vertical portion main body 34A, and its tip (pressing portion) is arranged to face the eccentric roller 46 at a constant interval. The X-direction positioning reference pin 58 is arranged between them. That is, when the head module 24 is attached to the base frame 50, the X-direction positioning reference pin 58 provided on the base frame 50 side is fitted between the eccentric roller 46 and the plunger 48, and the eccentric roller 46 and the plunger 48 are connected. It is supposed to be pinched by.

  Then, the plunger 48 presses the X-direction positioning reference pin 58, which is in contact with the eccentric roller 46, in the X-direction, and the head module 24 is biased in the X-direction. ..

  According to the X-direction mounting position adjusting means configured in this way, when the motor 92 of the nozzle position adjusting device 90 described later is rotated and the screw gear 102 is rotated via the drive shaft 122 and the transmission shaft 104, the screw The rotation of the gear 102 is transmitted to the helical gear 47, and the eccentric roller 46 rotates with the rotation of the helical gear 47. When the eccentric roller 46 rotates, the head module 24 moves in the X direction according to the rotation amount.

  Further, as shown in FIG. 3, a guide groove 62 for attaching the bracket 30 to the base frame 50 is formed in the vertical portion 34 of the bracket 30. The guide groove 62 is formed in the vertical portion main body 34A of the vertical portion 34, and has a predetermined width and is formed vertically downward (Z direction) from the upper surface portion of the vertical portion main body 34A at a predetermined depth.

  When the head module 24 (bracket 30) is attached to the base frame 50, a pair of Y-direction guide posts 76 provided on the base frame 50 side are fitted into the guide grooves 62. Therefore, the width of the guide groove 62 is formed to be substantially the same as the width (diameter) of the Y-direction guide post 76. An arc-shaped enlarged diameter portion 64 is formed at a substantially central portion of the tip portion (lower end portion) of the guide groove 62.

  Therefore, when the head module 24 is attached to the predetermined position of the base frame 50, the pair of Y-direction guide posts 76 provided on the base frame 50 side are accommodated in the expanded diameter portion 64. As a result, the head module 24 attached to the base frame 50 is movably supported.

  Further, the expanded diameter portion 64 is formed at a position corresponding to the Y-direction guide post 76, and when the head module 24 is attached to the base frame 50, the Y-direction guide post 76 is housed at a substantially central position thereof. It has become. In the present embodiment, when the head module 24 is attached to the base frame 50, the enlarged diameter portion 64 is formed so as to form a circle centered on the axis of the Y-direction guide post 76.

  The circle is formed larger than the diameter of the Y-direction guide post 76. Thus, when the head module 24 is attached to the base frame 50, the head module 24 can be movably supported within a predetermined range. Moreover, when the head module 24 is attached to the base frame 50, the head module 24 can be attached without rattling.

  A pair of notches 66 and 68 are formed on both sides of the guide groove 62. When the head module 24 (bracket 30) is attached to the base frame 50, the lock bar 79 of the Z-direction hanging rod 78 provided on the base frame 50 side is engaged with the pair of notches 66 and 68. It has become. In other words, the bracket 30 is locked to the base frame 50 by the lock bar 79 of the Z-direction hanging rod 78 engaging with the notches 66 and 68.

  The pair of notches 66 and 68 are formed to include the wall surfaces of the guide groove 62 that face each other, and are formed with a predetermined depth on the outer surface side and the inner surface side of the vertical portion 34 of the bracket 30, respectively. That is, one notch 66 is formed on the outer surface side of the vertical portion 34, and the other notch 68 is formed on the inner surface side of the vertical portion 34.

  Further, the vertical portion 34 of the bracket 30 is provided with a magnet 60 for detecting a displacement amount (movement amount) of at least the X direction of the head module 24 when the head module 24 is attached to the base frame 50. The magnet 60 constitutes a position detecting means together with a magnetic sensor 74 provided on the base frame 50 side. When the head module 24 is attached to the base frame 50, the magnet 60 is arranged so as to face the magnetic sensor 74 provided on the base frame 50 side.

[Structure of base frame]
As shown in FIGS. 3 and 5, the base frame 50 as a support member is mainly configured by an upper frame 70 as a top plate and a lower frame 72 as a support plate. The upper frame 70 is a rectangular plate having a thickness that ensures rigidity, and is arranged horizontally (parallel to the XY plane).

  The lower frame 72 is also in the shape of a rectangular plate having a thickness that ensures rigidity, and is arranged vertically (parallel to the XZ plane) below the upper frame 70. The head module 24 is attached to the lower frame 72. That is, the lower frame 72 functions as a mounting portion for mounting the head module 24.

  Further, the base frame 50 is provided with a head module support means for supporting the head module 24. In detail, since the head module 24 is attached to the lower frame 72, the head module support means is provided on the lower frame 72 for each head module 24.

  The head module support means is composed of a pair of Y-direction guide posts 76 and a Z-direction suspension rod 78. The Y-direction guide posts 76 are formed in a cylindrical shape having a flange portion 76A at the top, and are arranged side by side at regular intervals in the vertical direction (Z direction). The Y-direction guide post 76 is provided so as to project from the outer surface of the lower frame 72, and is arranged parallel to the Y-direction.

  Therefore, when the head module 24 is attached to the base frame 50, the guide groove 62 formed in the vertical portion 34 of the bracket 30 is fitted and attached to the pair of Y-direction guide posts 76. Since the width (diameter) of the Y-direction guide post 76 is formed to be substantially the same as the width of the guide groove 62, the head module 24 can be mounted without rattling.

  Further, the pair of Y-direction guide posts 76 are each provided with a Y-direction pressing plate 80. The Y-direction pressing plate 80 is formed in a ring shape, and is provided on the outer peripheral surface of the Y-direction guide post 76 so that the Y-direction guide post 76 is inserted in the inner peripheral portion thereof.

  Further, each of the pair of Y-direction guide posts 76 is provided with a Y-direction pressing spring 82 as Y-direction biasing means. The Y-direction pressing spring 82 is fitted to the Y-direction guide post 76 so that the Y-direction guide post 76 is inserted into the inner peripheral portion of the Y-direction pressing spring 82. That is, the Y-direction pressing spring 82 is arranged between the flange portion 76A of the Y-direction guide post 76 and the Y-direction pressing plate 80.

  As described above, when the head module 24 is attached to the base frame 50, the pair of Y-direction guide posts 76 are fitted into the guide grooves 62. When the pair of Y-direction guide posts 76 are fitted into the guide groove 62, the Y-direction pressing plate 80 engages with the vertical portion 34 of the bracket 30. Since the Y-direction pressing plate 80 is biased in the Y-direction by the Y-direction pressing spring 82, the head module 24 is pressed toward the base frame 50 by the Y-direction pressing plate 80.

  Further, the pair of Y-direction guide posts 76 are arranged at regular intervals in the vertical direction as described above, but the Y-direction pressing springs 82 provided in each Y-direction guide post 76 have different biasing forces, that is, springs. Different constants are used. Specifically, the Y-direction pressing spring 82 provided on the lower Y-direction guide post 76 has a larger spring constant than the Y-direction pressing spring 82 provided on the upper Y-direction guide post 76. ing.

  As a result, the pressing force by the Y-direction pressing plate 80 provided on the lower Y-direction guide post 76 becomes larger than the pressing force by the Y-direction pressing plate 80 provided on the upper Y-direction guide post 76. It is configured. This is to prevent the head module 24 from tilting when adjusting the mounting position in the X direction.

  That is, by increasing the spring constant of the Y-direction pressing spring 82 provided on the lower Y-direction guide post 76 near the X-direction mounting position adjusting means, the center of the rotational moment at the time of adjusting the mounting position in the X direction is the X direction. The head module 24 is set near the mounting position adjusting means so that the head module 24 can be prevented from inclining (when the spring constant of the Y-direction pressing spring 82 provided in the upper Y-direction guide post 76 is increased, the head module 24 is provided. The upper side of the becomes difficult to move, and it is easy to tilt).

  In addition, in the bar head 20 according to the present embodiment, the X-direction mounting position adjusting means is provided in the vicinity of the lower Y-direction guide post 76, so that the Y-direction provided in the lower Y-direction guide post 76 is provided. The spring constant of the pressing spring 82 is made larger than that of the Y-direction pressing spring 82 provided on the upper Y-direction guide post 76.

  However, when the X-direction mounting position adjusting means is provided close to the upper Y-direction guide post 76, the spring constant of the Y-direction pressing spring 82 provided in the upper Y-direction guide post 76 is set to the lower side. Is larger than the spring constant of the Y-direction pressing spring 82 provided in the Y-direction guide post 76.

  That is, the spring constant of the Y-direction pressing spring 82 of the Y-direction guide post 76, which is installed closer to the X-direction mounting position adjusting means, is greater than the spring constant of the Y-direction pressing spring 82 of the Y-direction guide post 76 on the other side. It is preferable to make it large. Accordingly, it is possible to prevent the head module 24 from tilting when adjusting the mounting position in the X direction.

  The Z-direction hanging rod 78 is formed in a columnar shape, and an operating portion 77 having a diameter larger than that of the Z-direction hanging rod 78 is formed at the top thereof. The Z-direction suspension rod 78 is arranged parallel to the Z-direction. A Z-direction hanging rod insertion hole 84 for mounting the Z-direction hanging rod 78 is formed in the upper frame 70.

  The Z-direction hanging rod insertion hole 84 is formed along the Z-direction and penetrates from the upper surface portion to the lower surface portion of the upper frame 70. The Z-direction suspension rod 78 is inserted into the Z-direction suspension rod insertion hole 84 and attached to the upper frame 70. The Z-direction hanging rod 78 attached to the upper frame 70 is arranged on the front side of the outer surface of the lower frame 72.

  The Z-direction suspension rod 78 is arranged on the same straight line as the pair of Y-direction guide posts 76, and is arranged above the pair of Y-direction guide posts 76. Therefore, when the head module 24 is attached to the base frame 50, the Z-direction hanging rod 78 is housed in the guide groove 62.

  The Z-direction suspension rod 78 is provided with a Z-direction pressing spring 86 as Z-direction biasing means. The Z-direction pressing spring 86 is provided on the Z-direction suspending rod 78 so that the Z-direction suspending rod 78 is inserted into the inner peripheral portion thereof, and the operating portion of the Z-direction suspending rod 78 is provided. It is provided between 77 and the upper frame 70. As a result, the Z-direction suspension rod 78 is biased upward by the biasing force of the Z-direction pressing spring 86 (biased in the direction of pulling up toward the upper frame 70).

  A lock bar 79 is provided at the tip (lower end) of the Z-direction suspension rod 78. The lock bar 79 is provided so as to project radially outward from the peripheral surface of the Z-direction suspension rod 78 (is provided orthogonally to the axial direction of the Z-direction suspension rod 78), and is a guide groove. It is formed longer than the width of 62.

  The lock bar 79 is engaged with the cutouts 66 and 68 formed in the guide groove 62 on the head module 24 side to lock the head module 24. Here, the lock bar 79 is fitted into the notches 66 and 68 by rotating the Z-direction suspension rod 78.

  That is, since the lock bar 79 is formed longer than the width of the guide groove 62, the head module 24 is attached to the base frame 50 in the same direction as the width direction (X direction) of the guide groove 62. Then, the lock bar 79 comes into contact with the inlet portion (upper end portion) of the guide groove 62, and the head module 24 cannot be attached.

  Therefore, when the head module 24 is attached to the base frame 50, the lock bar 79 is positioned so as not to contact the wall surface of the guide groove 62 (in the state shown in FIG. 5), and the head module 24 is moved in this state. Attach to the base frame 50. Then, when the head module 24 is attached to the base frame 50 and the locking bar 79 is located at the position where the notches 66 and 68 are formed, the Z-direction suspension rod 78 is rotated. Then, the locking bar 79 fits into the notches 66 and 68.

  Here, since the Z-direction suspension rod 78 is biased upward by the Z-direction pressing spring 86, when the lock bar 79 is fitted into the cutout portions 66 and 68, the lock bar 79 is cut out. It engages with the portions 66 and 68 (engages with the ceiling surface of the inner peripheral portion of the notches 66 and 68). As a result, the head module 24 is attached to the base frame 50 while being urged upward.

  As described above, when the axial direction of the locking bar 79 becomes parallel to the width direction (X direction) of the guide groove 62, the locking bar 79 fits into the notches 66 and 68. Therefore, the position of the lock bar 79 in this case is the lock position. On the other hand, when the axial direction of the lock bar 79 is orthogonal to the width direction (X direction) of the guide groove 62, the lock bar 79 does not come into contact with the wall surface of the guide groove 62 (removes from the notches 66 and 68). Therefore, the position of the lock bar 79 in this case is the unlock position.

  Further, the base frame 50 includes a base frame Y-direction positioning means for performing Y-direction positioning when mounting the head module 24 on the base frame 50, and a base frame Z-direction positioning means for performing Z-direction positioning. Is provided.

  The base frame Y-direction positioning means includes two fixed-contact base frame Y-direction positioning members 52 as reference surfaces that form the base frame Y-direction positioning member, and one movable contact that also forms the base frame Y-direction positioning member. It is composed of the base frame Y direction positioning member 54 (see FIG. 6).

  Each of the two fixed contact base frame Y-direction positioning members 52 is formed of a pin (for example, a stainless steel pin) having rigidity, and is formed to have higher hardness than the head module Y-direction fixed contact member 36. The two fixed contact base frame Y-direction positioning members 52 are provided so as to project downward (downward in the Z direction) from the lower surface of the lower frame 72.

  Further, the two fixed contact base frame Y direction positioning members 52 are arranged at the same intervals as the installation intervals of the two head module Y direction fixed contact members 36 provided on the head module 24 side, and the head module 24 is mounted on the base frame 50. When mounted, the two head module Y-direction fixed contact members 36 are provided at positions where they abut on the peripheral surface. That is, the two fixed contact base frame Y-direction positioning members 52 are provided corresponding to the two head module Y-direction fixed contact members 36 provided on the head module 24 side.

  On the other hand, the movable contact base frame Y-direction positioning member 54 is also made of a pin having rigidity (for example, a stainless steel pin), and is formed to have higher hardness than the head module Y-direction movable contact member 38. The movable contact base frame Y-direction positioning member 54 is housed in a recess formed on the outer surface of the lower frame 72, and is arranged parallel to the Y direction.

  The movable contact base frame Y-direction positioning member 54 is provided at a position where the head module Y-direction movable contact member 38 on the head module 24 side abuts the tip end surface of the head module 24 when the head module 24 is attached to the base frame 50. .. That is, the movable contact base frame Y-direction positioning member 54 is provided corresponding to the head module Y-direction movable contact member 38 provided on the head module 24 side.

  Here, as described above, when the head module 24 is attached to the base frame 50, the head module 24 is pressed toward the base frame 50 by the Y-direction pressing plate 80 provided on the Y-direction guide post 76.

  Therefore, when the head module 24 is attached to the base frame 50, the two head module Y-direction fixed contact members 36 provided on the head module 24 side are fixed to the two fixed contact base frame Y directions provided on the base frame 50 side. The positioning member 52 is pressed (contacted).

  Then, the head module Y direction movable contact member 38 provided on the head module 24 side is pressed (contacted) with the movable contact base frame Y direction positioning member 54 provided on the base frame 50 side. As a result, the head module 24 attached to the base frame 50 is positioned in the Y direction with respect to the base frame 50.

  As described above, the fixed contact base frame Y-direction positioning member 52 is formed to have higher hardness than the head module Y-direction fixed contact member 36. The movable contact base frame Y-direction positioning member 54 is formed to have higher hardness than the head module Y-direction movable contact member 38.

  As a result, the positional stability during positioning is improved, and the repeat accuracy when the head module 24 is replaced can be improved. As a method of increasing the hardness, it is possible to use a material having high hardness, a method of increasing the hardness by performing a surface treatment, or the like.

  The base frame Z direction positioning means for positioning the head module 24 in the Z direction with respect to the base frame 50 is composed of a pair of base frame Z direction contact members 56. The pair of base frame Z-direction contact members 56 are composed of rigid pins (for example, stainless steel pins) and are formed to have a higher hardness than the head module Z-direction contact member 42.

  The pair of base frame Z-direction contact members 56 are provided so as to project from the outer surface of the lower frame 72, and are arranged parallel to the Y direction. Further, the pair of base frame Z-direction contact members 56 are at the same intervals as the installation intervals of the pair of head module Z-direction contact members 42 provided on the head module 24 side, and when the head module 24 is attached to the base frame 50, It is provided at a position where the pair of head module Z-direction contact members 42 abut. That is, the pair of base frame Z-direction contact members 56 is provided corresponding to the head module Z-direction contact member 42 provided on the head module 24 side.

  As described above, when the head module 24 is attached to the base frame 50, the head module 24 is urged upward by the action of the Z-direction pressing spring 86 provided on the Z-direction suspension rod 78. Therefore, when the head module 24 is attached to the base frame 50, the pair of head module Z-direction contact members 42 provided on the head module 24 abut on the pair of base frame Z-direction contact members 56 provided on the base frame 50. To be done. As a result, the head module 24 is positioned in the Z direction with respect to the base frame 50.

  As described above, the base frame Z-direction contact member 56 is formed to have higher hardness than the head module Z-direction contact member 42. As a result, the positional stability during positioning is improved, and the repeat accuracy when the head module 24 is replaced can be improved. As a method of increasing the hardness, it is possible to use a material having a high hardness or a method of increasing the hardness by performing a surface treatment, as in the above.

  The base frame 50 is provided with an X-direction positioning reference pin 58, which is a component of the X-direction mounting position adjusting means. The X-direction positioning reference pin 58 is composed of a pin having rigidity (for example, a pin made of stainless steel), and is provided so as to project downward (downward in the Z direction) from the lower surface portion of the lower frame 72.

  Here, the X-direction positioning reference pin 58 is arranged at a position fitted between the eccentric roller 46 and the plunger 48 provided on the head module 24 side when the head module 24 is attached to the base frame 50. That is, when the head module 24 is attached to the base frame 50, the X-direction positioning reference pin 58 is fitted between the eccentric roller 46 and the plunger 48 and is sandwiched between them. When the eccentric roller 46 is rotated in this state, the head module 24 is displaced in the X direction with respect to the base frame 50.

  Further, the lower frame 72 of the base frame 50 is provided with a magnetic sensor 74 which constitutes a position detecting means together with the magnet 60 provided on the head module 24 side. A magnetic sensor mounting portion 88 is provided at a predetermined position on the lower frame 72, and the magnetic sensor 74 is mounted on the magnetic sensor mounting portion 88. When the head module 24 is attached to the base frame 50, the magnetic sensor 74 is arranged at a position facing the magnet 60 provided on the head module 24 side.

  When the head module 24 attached to the base frame 50 is displaced in the X direction by the X-direction attachment position adjusting means, the displacement amount is detected by the magnetic sensor 74. That is, information on the amount of displacement detected by the magnetic sensor 74 is output to a control unit (not shown).

  The material of the base frame 50 is not particularly limited, but it is preferable to use a material that is not easily affected by heat so that the head module 24 can be mounted with high accuracy. Specifically, it is preferable to use a material having a linear expansion coefficient of 10 ppm/° C. or less, which is lower than the iron-based linear expansion coefficient (about 15 ppm/° C.). As a result, it is possible to prevent the mounting position of the head module 24 from changing due to the influence of heat. As such a material, for example, ceramics, Invar, or Super Invar can be used.

<How to attach the head module>
Next, a method of mounting the head module 24 will be described based on FIGS. 6 to 8.

  As described above, the lower frame 72 of the base frame 50 is provided with the head module support means. The head module 24 is attached to the lower frame 72 of the base frame 50 by using this head module support means. The attachment method itself is the same for all parts.

  As shown in FIGS. 6 and 7, the head module 24 is attached to the base frame 50 by the operation of pushing the head module 24 upward from below. First, at a position below the base frame 50, the horizontal portion 32 of the bracket 30 of the head module 24 is placed in a posture parallel to the upper frame 70 of the base frame 50.

  Further, the vertical portion 34 of the bracket 30 is placed in a posture parallel to the lower frame 72 of the base frame 50. In this state, the position of the guide groove 62 formed in the bracket 30 of the head module 24 is aligned with the position of the Y-direction guide post 76 provided in the lower frame 72 of the base frame 50.

  Next, the head module 24 is pushed up toward the base frame 50 so that the Y-direction guide post 76 fits in the guide groove 62. When the Y-direction guide post 76 is fitted in the guide groove 62, the head module 24 is vertically pushed up using the Y-direction guide post 76 as a guide. Accordingly, rattling at the time of mounting can be prevented, and the head module 24 can be prevented from coming into contact with other members (head module 24 already mounted, etc.).

  When the Y-direction guide post 76 is fitted in the guide groove 62 and the head module 24 is pushed up, the Z-direction hanging rod 78 provided on the base frame 50 is housed in the guide groove 62. Here, the Z-direction hanging rod 78 is provided with a locking bar 79.

  Therefore, when the head module 24 is attached to the base frame 50, the locking bar 79 is positioned at the unlocked position so that the locking bar 79 does not contact the wall surface of the guide groove 62. As a result, it is possible to prevent the locking bar 79 from contacting the entrance portion of the guide groove 62 and inhibiting the movement of the head module 24.

  When the head module 24 is pushed up toward the base frame 50 as described above, the pair of head module Z-direction contact members 42 provided on the bracket 30 of the head module 24 are paired with the base frame 50 provided on the base frame 50. It contacts the Z-direction contact member 56.

  Then, when the pair of head module Z-direction contact members 42 come into contact with the pair of base frame Z-direction contact members 56 provided on the base frame 50, a pair of cutout portions formed in the guide groove 62 of the head module 24. 66 and 68 are located at the installation position of the lock bar 79 provided on the Z-direction suspension rod 78.

  In this state, the Z-direction suspension rod 78 is rotated to position the lock bar 79 at the lock position. As a result, the locking bar 79 is fitted into the notches 66 and 68, and the locking bar 79 is locked to the ceiling surface of the inner peripheral portion of the notches 66 and 68. As a result, as shown in FIG. 8, the head module 24 is attached to the base frame 50 while being suspended from the Z-direction suspension rod 78.

  Here, the Z-direction hanging rod 78 is provided with a Z-direction pressing spring 86. Therefore, when locked by the Z-direction suspension rod 78, the head module 24 is pushed upward by the action of the Z-direction pressing spring 86. As a result, the pair of head module Z-direction contact members 42 provided on the head module 24 abut on the pair of base frame Z-direction contact members 56 provided on the base frame 50. As a result, the head module 24 is positioned in the Z direction with respect to the base frame 50.

  The pair of Y-direction guide posts 76 fitted in the guide grooves 62 are provided with Y-direction pressing springs 82. The Y-direction pressing spring 82 presses the head module 24 toward the base frame 50 via the Y-direction pressing plate 80. As a result, the head module Y-direction fixed contact member 36 and the head module Y-direction movable contact member 38 provided on the head module 24 are fixed to the fixed-contact base frame Y-direction positioning member 52 and the movable contact provided on the base frame 50. The base frame Y direction positioning member 54 is pressed (contacted). As a result, the head module 24 is positioned in the Y direction with respect to the base frame 50.

  When the head module Z-direction contact member 42 comes into contact with the base frame Z-direction contact member 56, the Y-direction guide post 76 is housed in the expanded diameter portion 64 formed in the guide groove 62. As a result, the head module 24 is attached to the base frame 50 so as to be displaceable in at least the X direction.

  The position of the head module Z-direction contact member 42 and the head module Y-direction movable contact member 38 can be adjusted, but this position adjustment is preferably performed in advance (for example, at the time of shipping). As described above, the head module 24 is attached to the base frame 50. Then, the mounting work is performed on all the head modules 24.

  Here, it is preferable that the mounting work is performed in order from one end to the other end of the base frame 50. At this time, the first head module 24 (the head module 24 to be mounted first) is moved in the X direction. It is preferable that the displacement is adjusted by fitting it to the central value of the adjustment range. As a result, it is possible to reduce the risk that the subsequent mounting position of the head module 24 deviates from the adjustment range, and prevent the adjustment range from being unnecessarily large.

  In this way, the base frame 50 to which all the head modules 24 are attached is held by the predetermined holder provided in the inkjet recording apparatus 10 and mounted on the inkjet recording apparatus 10.

<Nozzle position adjustment device>
In the ink jet recording apparatus 10 according to the present embodiment having the above-described configuration, the nozzle position adjusting device 90 that automatically drives the X-direction attaching position adjusting means and the θ _Z- direction attaching position adjusting means will be described in detail. .

In the inkjet recording apparatus 10 according to the present embodiment, four bar heads 20K, 20C, 20M and 20Y are sequentially arranged in the transport direction of the transport drum 12. Therefore, in order to record a high-quality image, the head modules 24 of the bar heads 20K, 20C, 20M, and 20Y are adjusted so that the bar heads 20K, 20C, 20M, and 20Y have the same recording area width. It is necessary to adjust the mounting position in the X direction and the position in the rotation direction about the normal line direction of the nozzle surface 22, that is, the mounting position in the θ _Z direction.

Therefore, a reference bar head (for example, the bar head 20K) is determined, and the correction amount of the mounting position of the head module 24 of the remaining bar heads is adjusted by a control unit (not shown) so as to match the print area width of the bar head. calculate. Based on this correction amount, the control unit drives the nozzle position adjusting device 90 to adjust the mounting position of each head module 24 in the X direction and the mounting position in the θ _Z direction. This will be described below.

[Structure of adjustment mechanism]
As shown in FIG. 1, FIG. 3, FIG. 9, and FIG. 10, the nozzle position adjusting device 90 includes an adjusting mechanism 100 for adjusting the mounting position of the head module 24 in the X direction and the mounting position of the θ _Z direction, and a control unit. And a motor 92, 94, 96, 98 as a driving means for driving the adjusting mechanism 100. The adjusting mechanism 100 and the motors 92, 94, 96, 98 (nozzle position adjusting device 90) are provided on the upper side of the upper frame 70.

  The adjusting mechanism 100 includes a transmission shaft 104 having a screw gear (worm) 102 attached to a lower end thereof as a first transmission portion, and a second transmission portion having an eccentric roller 106 as a second eccentric cam attached to a lower end portion thereof. And a transmission shaft 108 of. That is, the screw gear 102 is connected so as to be coaxial with the transmission shaft 104, and the eccentric roller 106 is connected so as to be eccentric (shift the shaft) with the transmission shaft 108.

The eccentric roller 106 is arranged so as to contact the outer surface of the second overhanging portion 34C. By the rotation of the eccentric roller 106 in the forward and reverse directions with the transmission shaft 108 as the rotation axis, the second overhanging portion 34C resists the urging force of the coil spring urging the head module Y-direction fixed contact member 36, or the same. By moving in the Y direction by the urging force, the mounting position of the head module 24 in the θ _Z direction is adjusted.

  The transmission shafts 104 and 108 are provided for each head module 24. More specifically, as shown in FIG. 3, on the outer surface of the vertical portion main body 34</b>A of the vertical portion 34, ring-shaped guide portions 112 and 114 in plan view, through which the transmission shaft 104 is inserted, are vertically separated and integrated. Is provided for the purpose. Further, the transmission shaft 104 is integrally formed with a ring-shaped flange portion 104A which is brought into contact with and locked by the upper surface of the upper guide portion 112.

  That is, the transmission shaft 104 is inserted into the guide portions 112 and 114 from above, and the flange portion 104A is retained by the upper guide portion 112 so that the transmission shaft 104 is prevented from falling off. It is adapted to be attached to the lower end portion of the transmission shaft 104 protruding downward from the guide portion 114. A concave portion 105 having a “concave” shape in side view (or a front view) into which a convex portion 123 formed on a lower end portion of a drive shaft 122 described later is fitted is formed at an upper end portion of the transmission shaft 104. ..

  On the other hand, the support plate 110 is integrally provided on the second protrusion 34C of the vertical portion 34. On the outer surface of the support plate 110, ring-shaped guide portions 116 and 118 in plan view, through which the transmission shaft 108 is inserted, are integrally provided so as to be vertically separated from each other. The transmission shaft 108 is integrally formed with a ring-shaped flange portion 108A that is brought into contact with the upper surface of the upper guide portion 116 and locked.

  That is, the transmission shaft 108 is inserted into the guide portions 116 and 118 from above, and the flange portion 108A is retained by the upper guide portion 116 so as to prevent the transmission shaft 108 from falling off. It is adapted to be attached to the lower end portion of the transmission shaft 108 protruding downward from the guide portion 118. Further, a concave portion 109 having a “concave” shape in a side view (or a front view) into which a convex portion 125 formed on a lower end portion of a drive shaft 124 described later is fitted is formed at an upper end portion of the transmission shaft 108. .. In addition, in FIG. 6, the support plate 110, the transmission shafts 104, 108, and the like are omitted.

  The adjustment mechanism 100 includes a drive shaft 122 as a first actuator that is fitted to the transmission shaft 104 in a non-rotatable manner to transmit the rotational driving force, and a transmission shaft 108 that is fitted to the transmission shaft 108 in a relatively non-rotatable manner to transmit the rotational driving force. And a drive shaft 124 as a second actuator. Then, the lower end of each drive shaft 122, 124 has a convex shape of a "convex" shape in a side view (or a front view) that fits into a recess 105, 109 formed in the upper end of each transmission shaft 104, 108, respectively. Portions 123 and 125 are formed.

  Further, a motor 92 capable of rotating the drive shaft 122 in forward and reverse directions is attached to the upper end of the drive shaft 122. A motor 94 capable of rotating the drive shaft 124 in forward and reverse directions is attached to the upper end of the drive shaft 124. Therefore, by rotating the motors 92 and 94 in the forward and reverse directions, the transmission shafts 104 and 108 rotate in the forward and reverse directions via the drive shafts 122 and 124, whereby the screw gear 102 and the eccentric roller 106 are moved. It is configured to rotate in the forward and reverse directions.

  The motors 92, 94 of the drive shafts 122, 124 are attached to one end of a rectangular flat plate-shaped lifting member 120 whose longitudinal direction is the X direction. The other end of the elevating member 120 is integrally provided with one end of a guide member (not shown) in which a shaft 126 whose Z direction is the axial direction is inserted, and the other end of the guide member. , The Z direction is the axial direction, and the ball screw 128 is screwed.

  That is, a cylindrical portion through which the shaft 126 is inserted is formed at one end of the guide member, and a screw hole portion into which the ball screw 128 is screwed is formed at the other end of the guide member. Further, a motor 96 capable of rotating the ball screw 128 in the forward and reverse directions is attached to the upper end of the ball screw 128.

  Therefore, the ball screw 128 is rotated in the forward and reverse directions by rotationally driving the motor 96 in the forward and reverse directions, and the elevating member 120 is elevated and lowered along the shaft 126 via the guide member. That is, the drive shafts 122 and 124 are moved up and down together with the motors 92 and 94 by the rotational driving of the motor 96 in the forward and reverse directions.

  The shaft 126 and the ball screw 128 are provided on the outer surface of the rectangular flat plate-shaped moving member 130 whose longitudinal direction is the Z direction. A shaft 132 whose axial direction is the X direction is inserted through the upper part of the moving member 130, and a ball screw 134 whose axial direction is the X direction is screwed into the lower part of the moving member 130. That is, a through hole 130A into which the shaft 132 is inserted is formed in the upper part of the moving member 130, and a screw hole portion 130B into which the ball screw 134 is screwed is formed in the lower part of the moving member 130.

  Then, a motor 98 capable of rotationally driving the ball screw 134 in the forward and reverse directions is attached to one end of the ball screw 134. Therefore, the ball screw 134 is rotated in the forward and reverse directions by the rotational driving of the motor 98 in the forward and reverse directions, and the moving member 130 is moved along the shaft 132 (along the X direction). That is, the drive shafts 122 and 124 are configured to move along with the motors 92 and 94 along the X direction by rotationally driving the motor 98 in the forward and reverse directions.

  The moving member 130, the shaft 132, and the ball screw 134 constitute a moving mechanism that moves the drive shafts 122 and 124 along the X direction (the direction intersecting the conveyance direction of the paper P). The elevating member 120, the shaft 126, and the ball screw 128 constitute an elevating mechanism (first elevating mechanism and second elevating mechanism) for elevating the drive shafts 122 and 124 along the Z direction.

  Further, in the present embodiment, since the drive shafts 122 and 124 are both moved up and down, a single elevating mechanism is provided. However, an elevating mechanism including an elevating member 120, a shaft 126, and a ball screw 128 is provided for each drive shaft 122 and 124. It may be provided. That is, a first elevating mechanism for elevating the drive shaft 122 and a second elevating mechanism for elevating the drive shaft 124 may be provided.

  Further, in the upper frame 70, through holes 136 and 138 having a circular shape in a plan view (along the Z direction) penetrating from the upper surface portion to the lower surface portion thereof (in the Z direction) are formed in order to insert the drive shafts 122 and 124, respectively. Plural sets are formed corresponding to 104 and 108. That is, the through holes 136 and 138 are formed at positions coaxial with the transmission shafts 104 and 108 provided for each head module 24. Note that, in FIG. 9, the transmission shafts 104 and 108 are drawn so as to project from the through holes 136 and 138 for easy understanding of the configuration.

Further, a magnet (not shown) is provided in the vertical portion main body 34A, and a hall element (not shown) is attached to the lower frame 72 so as to face the magnet. Then, when the head module 24 moves in the θ _Z direction, the position of the magnet with respect to the Hall element (distance between the magnet and the Hall element) changes. By detecting this change as a change in magnetic flux by the Hall element, the position of the head module 24 in the θ _Z direction is detected.

[Operation of adjustment mechanism]
Next, the operation of the adjusting mechanism 100 (nozzle position adjusting device 90) configured as described above will be described.

When it is necessary to adjust at least one of the mounting position in the X direction and the mounting position in the θ _Z direction of the head module 24, the control unit drives the motor 98 to move the moving member 130 and adjust the mounting position of the head module. Move to the position corresponding to 24. Then, the control unit drives the motor 96 to lower the drive shafts 122 and 124.

  That is, the drive shafts 122 and 124 are inserted into the through holes 136 and 138 formed in the upper frame 70 from above, and the protrusions 123 and 125 formed at the lower ends of the drive shafts 122 and 124 are respectively inserted. The transmission shafts 104 and 108 are fitted into the recesses 105 and 109 formed on the upper ends thereof.

  After that, when adjusting the mounting position of the head module 24 in the X direction, the motor 92 is driven and the screw gear 102 is rotated via the drive shaft 122 and the transmission shaft 104. Then, the helical gear 47 meshing with the screw gear 102 rotates, and the eccentric roller 46 rotates via the shaft portion 46A.

  As a result, the reference pin 58 moves in the X direction against or against the biasing force of the plunger 48, that is, the head module 24 moves in the X direction according to the rotation amount of the eccentric roller 46. Move and adjust its position.

On the other hand, when adjusting the mounting position of the head module 24 in the θ _Z direction, the motor 94 is driven and the eccentric roller 106 is rotated via the drive shaft 124 and the transmission shaft 108. As a result, the one second overhanging portion 34C moves in the Y direction against or against the biasing force of the coil spring that biases the head module Y-direction fixed contact member 36.

  Here, the head module Y-direction fixed contact member 36 and the head module Y-direction movable contact member 38 provided on the other second overhanging portion 34C are the fixed contact base frame Y-direction positioning member 52 and the movable contact base, respectively. It is in contact with the frame Y-direction positioning member 54.

Therefore, when the eccentric roller 106 rotates, the head module 24 rotates in the θ _Z direction about the straight line connecting the head module Y-direction fixed contact member 36 and the head module Y-direction movable contact member 38. That is, the head module 24 moves along the θ _Z direction according to the rotation amount of the eccentric roller 106, and the position thereof is adjusted.

In this way, the mounting position of the head module 24 to be adjusted in the X direction and the mounting position in the θ _Z direction are adjusted, but when there is another head module 24 to be adjusted, the rotation drive of the motors 92, 94 is stopped. Then, the motor 96 is driven to rotate in the opposite direction to the above. Then, the drive shafts 122 and 124 are raised, the convex portions 123 and 125 are disengaged from the concave portions 105 and 109 of the transmission shafts 104 and 108, and the drive shafts 122 and 124 are upward from the through holes 136 and 138. Taken out.

Then, in this state, the motor 98 is rotationally driven to move the moving member 130 to a position corresponding to the head module 24 to be adjusted next, and the above steps are repeated. As described above, according to the nozzle position adjusting device 90 of the present embodiment, the mounting position in the X direction and the mounting position in the θ _Z direction of each head module 24 can be adjusted by the common driving unit.

  In other words, the motors 92 and 94 that rotate and drive the eccentric roller 46 (screw gear 102) and the eccentric roller 106 need not be provided for each head module 24. Therefore, a troublesome work such as connecting an electric wire to a motor provided in each head module 24 becomes unnecessary, and further, space saving of the bar head 20, particularly on the upstream side and the downstream side in the transport direction can be realized. ..

  More specifically, when the motors 92 and 94 are provided for each head module 24, the motors 92 and 94 are provided on the outer surface of each head module 24 (vertical portion 34). Therefore, the bar head 20 is bent downward due to the weight of the motors 92 and 94 to deteriorate the position accuracy, and at least one space on the upstream side and the downstream side of the bar head 20 in the transport direction is the installation space of the motors 92 and 94. It is taken as.

  However, according to the adjusting mechanism 100 (nozzle position adjusting device 90) according to the present embodiment, only one set of the motors 92 and 94 needs to be arranged on the upper side of the upper frame 70 where the space is relatively easy to take. It is possible to prevent the position of the motor 20 from bending downward and deteriorating the positional accuracy, and to prevent installation space for the motors 92 and 94 from being provided upstream and downstream of the bar head 20 in the transport direction.

Further, as a result, the bar heads 20K, 20C, 20M and 20Y can be arranged with a reduced distance in the transport direction. Therefore, it is possible to suppress or prevent the overlapping position of each color from being displaced. Further, the adjustment of the mounting position of the head module 24 in the X direction and the mounting position of the θ _Z direction is performed by rotating the eccentric rollers 46 and 106, respectively, so that the configuration is simple and fine adjustment is possible.

  Furthermore, according to the adjusting mechanism 100 (nozzle position adjusting device 90) of the present embodiment, since the transmission shafts 104 and 108 are provided for each head module 24, the lengths of the drive shafts 122 and 124 are relatively long. It can be short. Therefore, the strokes for raising and lowering the drive shafts 122 and 124 can be set within a relatively short range. Therefore, space saving on the upper side of each bar head 20 (upper frame 70) can also be realized.

  Although the nozzle position adjusting device 90 according to the present embodiment has been described above with reference to the drawings, the nozzle position adjusting device 90 according to the present embodiment is not limited to the illustrated one, and the gist of the present disclosure will be described. The design can be changed as appropriate without departing from the scope. For example, the transmission shafts 104, 108 and the like are not limited to the configuration provided on the head module 24 side, and may be provided on the lower frame 72 side.

  In addition, the lower frames 72 are provided not only on one of the upstream side and the downstream side of the upper frame 70 in the transport direction, but also in a pair on both the upstream side and the downstream side of the upper frame 70 in the transport direction, as shown in FIG. It may be formed (standing). In this case, the head modules 24 are alternately arranged in the lower frame 72 on the upstream side in the transport direction and the lower frame 72 on the downstream side in the transport direction. That is, the head modules 24 are arranged in a staggered pattern in a plan view.

10 Inkjet recording device 12 Conveying drum 14 Gripper 15 In-line sensor 16 Paper feed unit 18 Paper ejection unit 20 Bar head (recording head)
22 Nozzle Surface 22A Nozzle Forming Area 24 Head Module 26 Inkjet Head 27 Electrical Equipment Piping Section 28 Head Body Section 30 Bracket 32 Horizontal Section 32A Opening 34 Vertical Section 34A Vertical Section 34B Overhanging Section 34C Overhanging Section 35 Eccentric Roller Mounting Hole 36 Head module Y direction fixed contact member (positioning member)
38 head module Y direction movable contact member 39 head module Y direction movable contact member insertion hole 40 head module Y direction movable contact member position adjusting screw 42 head module Z direction contact member 44 head module Z direction contact member insertion hole 45 head module Z direction Contact member position adjusting screw 46 Eccentric roller (first eccentric cam)
46A Shaft 47 Helical gear 48 Plunger 50 Base frame (support member)
52 Base frame for fixed contacts Y direction positioning member (reference surface)
54 Movable Contact Base Frame Y-Direction Positioning Member 56 Base Frame Z-Direction Contact Member 58 Reference Pin 60 Magnet 62 Guide Groove 64 Expanding Portion 66 Notch 68 Notch 70 Upper Frame (Top Plate)
72 Lower frame (support plate)
74 magnetic sensor 76 Y direction guide post 76A flange 77 operation part 78 rod 79 locking bar 80 Y direction pressing plate 82 Y direction pressing spring 84 rod insertion hole 86 Z direction pressing spring 88 magnetic sensor mounting part 90 nozzle position adjusting device 92 Motor 94 Motor 96 Motor 98 Motor 100 Adjustment mechanism 102 Screw gear 104 Transmission shaft (first transmission portion)
104A Flange portion 105 Recessed portion 106 Eccentric roller (second eccentric cam)
108 transmission shaft (second transmission portion)
108A Flange portion 109 Recess 110 Support plate 112 Guide portion 114 Guide portion 116 Guide portion 118 Guide portion 120 Elevating member (first elevating mechanism/second elevating mechanism)
122 Drive shaft (first actuator)
123 Convex portion 124 Drive shaft (second actuator)
125 convex portion 126 shaft (first elevating mechanism/second elevating mechanism)
128 ball screw (first lifting mechanism/second lifting mechanism)
130 Moving member (moving mechanism)
130A through hole 130B screw hole portion 132 shaft (moving mechanism)
134 Ball screw (moving mechanism)
136 Through Hole 138 Through Hole N Nozzle P Paper (Recording Medium)

Claims (6)

A plurality of head modules that have a nozzle surface composed of a plurality of nozzles that eject droplets onto a recording medium that is conveyed, and that are arranged in parallel in a direction that intersects the conveying direction of the recording medium to form a recording head;
A support member having a top plate extending in the intersecting direction and a support plate suspended from the top plate, and a support member to which the head module is attached;
Equipped with
The support plate has a reference surface with which a positioning member provided in the head module for positioning the position in the direction along the transport direction abuts,
The nozzle position adjusting device of a recording head, wherein the top plate has an adjusting mechanism that adjusts a position of the head module in the intersecting direction and a position of a rotating direction about a normal direction of the nozzle surface. The adjustment mechanism is
Adjusting the position of the head module in the intersecting direction by rotating the first eccentric cam,
The nozzle position adjusting device for a recording head according to claim 1, wherein the position of the nozzle module of the head module is adjusted in a rotational direction about the normal direction of the nozzle surface by rotating the second eccentric cam. The adjustment mechanism is
A first actuator for rotating the first eccentric cam;
A second actuator for rotating the second eccentric cam;
A moving mechanism for moving the first actuator and the second actuator in the intersecting direction,
The nozzle position adjusting device for a recording head according to claim 2, further comprising: The adjusting mechanism is
A first transmission part that is fitted to the first actuator such that the first actuator cannot rotate relative to the first eccentric cam;
A second transmission part, in which the second actuator is fitted so as not to rotate relative to each other, and which transmits a rotational driving force to the second eccentric cam;
The nozzle position adjusting device for a recording head according to claim 3, further comprising: The adjustment mechanism is
A first elevating mechanism for elevating and lowering the first actuator to be fitted to the first transmission portion;
A second elevating mechanism for elevating and lowering the second actuator to be fitted to the second transmission portion;
The nozzle position adjusting device for a recording head according to claim 4, further comprising:   The nozzle position adjusting device for a recording head according to any one of claims 1 to 5, wherein a pair of the support plates are vertically provided on the top plate.