JP2012030565A - Liquid ejecting head unit and liquid ejection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid ejecting head unit that secures the rigidity of a head fixing member even in a constitution in which the number of a liquid ejection head attached to the head fixing member is less than an original attachable number and eliminates the need for redesigning the head fixing member, and to provide a liquid ejection device with the same.SOLUTION: A dummy head 23 has an end surface 65 corresponding to a nozzle forming surface 53 of a recording head 18, and is mounted on a head attachment part 41 of a center part of a sub carriage in a head alignment direction so as to straddle a head inserting opening 28 in a state that the end surface is aligned on the same surface of the nozzle forming surface 53 of the recording head.

Description

  The present invention relates to a liquid ejecting head unit used in a liquid ejecting apparatus such as an ink jet recording apparatus, and a liquid ejecting apparatus including the liquid ejecting head unit, and in particular, a frame-like head to which a plurality of liquid ejecting heads can be attached. The present invention relates to a liquid ejecting head unit having a fixing member and a liquid ejecting apparatus.

  The liquid ejecting apparatus is an apparatus that includes a liquid ejecting head capable of ejecting liquid as droplets and ejects various liquids from the liquid ejecting head. A typical example of the liquid ejecting apparatus is an ink jet recording that includes an ink jet recording head (hereinafter referred to as a recording head) and performs recording by ejecting liquid ink as ink droplets from the nozzle of the recording head. An image recording apparatus such as an apparatus (printer) can be given. In recent years, the present invention is applied not only to this image recording apparatus but also to various manufacturing apparatuses such as a display manufacturing apparatus.

  In recent years, the above-mentioned printer is a multi-head type that employs a configuration in which a plurality of recording heads each having a nozzle group in which a plurality of nozzles are arranged are arranged and fixed on a head fixing member such as a subcarriage as a single head unit. There are some (see, for example, Patent Document 1). The sub-carriage is a frame-shaped flat plate member having openings where a plurality of recording heads are attached, and a sub-carriage made of synthetic resin has been put into practical use in order to reduce the weight. Each recording head is positioned with respect to the sub-carriage and fixed by screwing.

JP 2008-273109A

  Incidentally, as described above, the sub-carriage has a frame shape in which a portion to which the recording head is attached is open, and thus it is difficult to ensure rigidity. In addition, in a multi-head printer, the number of recording heads attached to the sub-carriage may be increased or decreased according to a change in specifications. For example, in the case of a configuration in which a smaller number of recording heads than the original number that can be attached to the sub-carriage are attached to the sub-carriage, if no measures are taken, the head attachment of the sub-carriage is reduced by the amount reduced. A space is generated at the position. When such a space is generated, the rigidity of the sub-carriage is reduced accordingly. As a result, when an external force is applied to the sub-carriage due to the recording paper to be printed coming into contact with the recording head or being wound in the space (so-called paper jam), the sub-carriage is deformed and each recording There is a possibility that the relative position of the head is displaced or tilted. For this reason, conventionally, it has been necessary to redesign the sub-carriage each time the specification is changed so that the above-described space does not occur.

  Such a problem is not only an ink jet recording apparatus equipped with a recording head for ejecting ink, but also a configuration in which a plurality of liquid ejecting heads are fixed to a frame-shaped head fixing member such as the sub-carriage. Similarly, other liquid ejecting head units and liquid ejecting apparatuses including the same exist.

  The present invention has been made in view of such circumstances, and an object of the present invention is to increase the rigidity of the head fixing member even in a configuration in which the number of liquid ejecting heads attached to the head fixing member is smaller than the original attachable number. An object of the present invention is to provide a liquid ejecting head unit that can be secured and does not require redesign of a head fixing member, and a liquid ejecting apparatus including the liquid ejecting head unit.

In order to achieve the above object, a liquid ejecting head unit of the present invention includes a liquid ejecting head having a nozzle forming surface in which a nozzle for ejecting liquid to a landing target is provided,
A head fixing member having a plurality of head mounting portions to which the liquid ejecting head is attached, and having an opening through which the liquid ejecting head attached to the head attaching portion is inserted;
A protective member for protecting the liquid jet head attached to the head attachment portion from the landing target;
With
The protection member has a front end surface corresponding to the nozzle formation surface of the liquid ejecting head, and the front end surface is aligned on the same surface as the nozzle formation surface of the liquid ejecting head. It is attached to the head attachment part in the center part in the head row direction so as to straddle the opening.

  According to the present invention, when the number of liquid ejecting heads attached to the head fixing member is smaller than the original mountable number, the protective member is attached to the head attaching portion in the center of the head fixing direction in the head fixing member. Thus, the protective member functions as a beam spanned across the center of the opening of the head fixing member, and the frame-like head fixing member is reinforced. This prevents the rigidity of the head fixing member from being lowered even in a configuration in which the number of liquid ejecting heads attached to the head fixing member is smaller than the original number that can be attached. As a result, for example, in a recording operation (printing operation) in which an image or the like is recorded while relatively moving the liquid ejecting head unit and a landing target such as recording paper, the head is fixed by contacting the landing target with the liquid ejecting head. Deformation of the head fixing member when an external force is applied to the member is suppressed, and displacement and inclination of the relative positions of the liquid ejecting heads are prevented. Therefore, if the number of liquid ejecting heads attached to the head fixing member is increased or decreased by changing the specification within the range of the original number that can be attached, the head fixing member can be shared without redesigning.

In addition, in a state where the protection member and each liquid ejecting head are attached to the head fixing member, the nozzle forming surface of each liquid ejecting head and the front end surface of the protecting member are located on the same surface. Further, it is possible to prevent the recording medium from coming into contact with the part of the protective member that protrudes further, or the landing target to be caught in the space formed by the tip surface retreating from the nozzle forming surface.
Furthermore, by attaching the protection member to the head attachment portion at the center of the head fixing direction in the head fixing member, the liquid ejecting heads are arranged symmetrically with the protection member interposed therebetween. Accordingly, even when the weight of the protection member is different from the weight of the liquid ejecting head, the weight distribution in the head arrangement direction of the head fixing member can be made symmetric from the center in the direction to both sides.

  The said structure WHEREIN: It is desirable for the said protection member to be removable with respect to the head attachment part of the said center part.

  According to the above configuration, since the protective member can be attached to and detached from the central head mounting portion, for example, by temporarily removing the protective member during replacement or repair work of the liquid jet head, the liquid jet The attachment / detachment work of the head becomes easy, and the workability of maintenance is improved. In addition, it is possible to easily cope with a case where the number of liquid ejecting heads attached to the head fixing member is increased or decreased by changing the specification within the range of the original attachable number.

The present invention further includes a liquid ejecting head having a nozzle forming surface in which a nozzle for ejecting liquid to a landing target is provided, and a plurality of head mounting portions to which the liquid ejecting head is mounted. A liquid ejecting head unit comprising: a head fixing member formed with an opening through which a liquid ejecting head to be attached is formed; and a protection member that protects the liquid ejecting head attached to the head attaching portion from the landing target. Equipped with
A liquid ejecting apparatus for ejecting liquid from the nozzles and causing the liquid ejecting head to land on the landing target while relatively moving the liquid ejecting head unit and the landing target in a head row arrangement direction;
The protection member has a front end surface corresponding to the nozzle formation surface of the liquid ejecting head, and the front end surface is aligned on the same surface as the nozzle formation surface of the liquid ejecting head. It is attached to the head attachment part in the center part in the head row direction so as to straddle the opening.

  According to the present invention, when the number of liquid ejecting heads attached to the head fixing member is smaller than the original mountable number, the protective member is attached to the head attaching portion in the center of the head fixing direction in the head fixing member. Thus, the protective member functions as a beam spanned across the center of the opening of the head fixing member, and the frame-like head fixing member is reinforced. This prevents the rigidity of the head fixing member from being lowered even in a configuration in which the number of liquid ejecting heads attached to the head fixing member is smaller than the original number that can be attached. As a result, for example, in a recording operation (printing operation) in which an image or the like is recorded while relatively moving the liquid ejecting head unit and a landing target such as recording paper, the head is fixed by contacting the landing target with the liquid ejecting head. Deformation of the head fixing member when an external force is applied to the member is suppressed, and displacement and inclination of the relative positions of the liquid ejecting heads are prevented. Therefore, if the number of liquid ejecting heads attached to the head fixing member is increased or decreased by changing the specification within the range of the original number that can be attached, the head fixing member can be shared without redesigning.

In addition, in a state where the protection member and each liquid ejecting head are attached to the head fixing member, the nozzle forming surface of each liquid ejecting head and the front end surface of the protecting member are located on the same surface. Further, it is possible to prevent the recording medium from coming into contact with the part of the protective member that protrudes further, or the landing target to be caught in the space formed by the tip surface retreating from the nozzle forming surface.
Furthermore, by attaching the protection member to the head attachment portion at the center of the head fixing direction in the head fixing member, the liquid ejecting heads are arranged symmetrically with the protection member interposed therebetween. Accordingly, even when the weight of the protection member is different from the weight of the liquid ejecting head, the weight distribution in the head arrangement direction of the head fixing member can be made symmetric from the center in the direction to both sides.

FIG. 3 is a perspective view illustrating a part of the internal configuration of the printer. It is a front view of a printer. It is a top view of a printer. FIG. 3 is a right side view of the printer. It is a top view of a carriage. It is a front view of a carriage. It is a right view of a carriage. It is sectional drawing which simplified and showed the structure of the carriage. It is a bottom view of a subcarriage, (a) is a state where a recording head or the like is not attached, and (b) is a state where a recording head or the like is attached. FIG. 3 is a perspective view illustrating a configuration of a recording head. It is a perspective view explaining the structure of a dummy head. It is a figure explaining the structure of the subcarriage in 2nd Embodiment, (a) is sectional drawing, (b) is a bottom view. It is a perspective view explaining the modification of a dummy head.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. In the embodiments described below, various limitations are made as preferred specific examples of the present invention. However, the scope of the present invention is not limited to the following description unless otherwise specified. However, the present invention is not limited to these embodiments. In the following, an ink jet recording apparatus (hereinafter referred to as a printer) will be described as an example of the liquid ejecting apparatus of the invention.

  1 is a perspective view showing a part of the internal configuration of the printer 1, FIG. 2 is a front view of the printer 1, FIG. 3 is a plan view of the printer 1, and FIG. 4 is a right side view of the printer 1. The illustrated printer 1 ejects ink, which is a kind of liquid, toward a recording medium (landing target) such as recording paper, cloth, or film. In the printer 1, a carriage 3 (a type of head unit holding member) is mounted inside a frame 2 so as to be capable of reciprocating in the main scanning direction, which is a direction intersecting the recording medium feeding direction. On the inner wall of the frame 2 on the back side of the printer 1, a pair of upper and lower guide rods 4 a and 4 b that are elongated along the longitudinal direction of the frame 2 are attached in parallel with a space therebetween. The carriage 3 is supported so as to be slidable with respect to the guide rods 4a and 4b by fitting the guide rods 4a and 4b to a bearing portion 7 (see FIG. 7) provided on the back side thereof. ing.

  A carriage motor 8 as a drive source for moving the carriage 3 is disposed on the back side of the frame 2 and on one end side in the main scanning direction (right end portion in FIG. 3). The drive shaft of the carriage motor 8 protrudes from the back surface side to the inner surface side of the frame 2, and a drive pulley (not shown) is connected to the tip portion. The drive pulley is rotated by driving the carriage motor 8. An idle pulley (not shown) is provided at a position opposite to the drive pulley in the main scanning direction (left end portion in FIG. 3). A timing belt 9 is stretched around these pulleys. A carriage 3 is connected to the timing belt 9. When the carriage motor 8 is driven, the timing belt 9 rotates as the driving pulley rotates, and the carriage 3 moves in the main scanning direction along the guide rods 4a and 4b.

  On the inner wall on the back surface of the frame 2, a linear scale 10 (encoder film) is stretched in parallel with the guide rods 4a and 4b along the main scanning direction. The linear scale 10 is a band-shaped (band-shaped) member made of a transparent resin film. For example, a plurality of opaque stripes crossing the band width direction are printed on the surface of a transparent base film. Each stripe has the same width and is formed at a constant pitch in the longitudinal direction of the band. A linear encoder that optically reads the stripe of the linear scale 10 is provided on the back side of the carriage 3 (not shown). The linear encoder is composed of, for example, a pair of light-emitting elements and light-receiving elements arranged opposite to each other, and outputs encoder pulses according to the difference between the light-receiving state at the transparent portion of the linear scale 10 and the light-receiving state at the stripe portion. It is like that. That is, the linear encoder is a kind of position information output means, and outputs an encoder pulse corresponding to the scanning position of the carriage 3 as position information in the main scanning direction. Thereby, a control unit (not shown) of the printer can control the recording operation on the recording medium by the head unit 17 while recognizing the scanning position of the carriage 3 based on the encoder pulse from the linear encoder. Then, the printer 1 moves forward when the carriage 3 moves from the home position on one end side in the main scanning direction toward the opposite end (full position), and returns when the carriage 3 returns from the full position to the home position side. A so-called bidirectional recording process is possible in which characters, images, and the like are recorded on the recording paper in both directions when moving.

  As shown in FIG. 3, an ink supply tube 14 that supplies ink of each color to each recording head 18 of the head unit 17 and a signal cable 15 that supplies a signal such as a drive signal are connected to the carriage 3. In addition, although not shown in the figure, the printer 1 has a cartridge mounting unit to which an ink cartridge (liquid supply source) storing ink is detachably mounted, a transport unit for transporting recording paper, and a recording head in a standby state at the home position. A capping unit for capping the 18 nozzle forming surface 53 (see FIG. 10), a suction pump for applying a negative pressure to the nozzle forming surface in a state where the nozzle forming surface 53 is capped (sealed) by the capping unit, and the like are provided. It has been. This suction pump also functions as a suction means for sucking mist from a suction nozzle of a dummy head 23 described later. A drainage tank is provided on the downstream side of the suction pump, and the ink sucked by the suction pump is discharged to the drainage tank.

  FIG. 5 is a plan (top) view of the carriage 3, FIG. 6 is a front view of the carriage 3, and FIG. 7 is a right side view of the carriage 3. FIG. 8 is a schematic cross-sectional view of the carriage 3. FIG. 5 shows a state where the carriage cover 13 is removed. The carriage 3 includes a carriage main body 12 in which a later-described head unit 17 (a kind of liquid ejecting head unit in the present invention) is mounted, and a carriage cover 13 that closes an upper opening of the carriage main body 12 and is divided vertically. It is a possible hollow box-shaped member. The carriage main body 12 includes a substantially rectangular bottom plate portion 12a and side wall portions 12b standing upward from four outer peripheral edges of the bottom plate portion 12a, and a space surrounded by the bottom plate portion 12a and the side wall portions 12b. The head unit 17 is accommodated therein. The bottom plate portion 12a has a bottom opening 19 through which the nozzle forming surface 53 of each recording head 18 of the accommodated head unit 17 is exposed. When the head unit 17 is housed in the carriage body 12, the nozzle forming surface 53 of each recording head 18 is below the bottom of the carriage body 12 from the bottom opening 19 of the bottom plate portion 12 a (the recording medium during the recording operation). Project to the side).

  An eccentric cam 21 (see FIG. 8) for adjusting the posture of the head unit 17 accommodated in the carriage body 12 is provided between the carriage body 12 and the head unit 17. The carriage body 12 is provided with a plurality of adjustment levers 20 for rotating these eccentric cams 21. By operating these adjusting levers 20, the eccentric cam 21 rotates and the cam diameter from the center of rotation to the outer peripheral surface increases or decreases. By the increase or decrease of this cam diameter, the carriage body of the head unit 17 accommodated in the carriage body 12. The posture such as the position and the inclination with respect to 12 can be adjusted.

  The head unit 17 is formed by unitizing a plurality of recording heads 18 and the like, and includes a sub-carriage 26 (a kind of head fixing member in the present invention) to which these recording heads 18 are attached, and a flow path member 24. ing. The sub-carriage 26 has a hollow box shape whose upper surface is opened from a plate-like base portion 26a to which the recording head 18 is fixed, and standing wall portions 26b that rise upward from the four outer peripheral edges of the base portion 26a. Is formed. A space surrounded by the base portion 26a and the four standing wall portions 26b functions as a housing portion 35 (see FIG. 8) that houses at least a part of the recording head 18 (mainly the sub tank 37). The sub-carriage 26 of the present embodiment is made of metal, for example, aluminum, and has higher rigidity than the carriage main body 12 and the carriage cover 13. The material of the subcarriage 26 is not limited to metal, and synthetic resin can also be used.

  As shown in FIG. 8, a flange portion 30 projects from the standing wall portion 26 b of the sub carriage 26 toward the side. In the flange portion 30, insertion holes 31 are formed corresponding to attachment screw holes (not shown) provided at the attachment position of the head unit 17 of the bottom plate portion 12 a of the carriage body 12. Then, the head unit fixing screws 22 are fastened to the mounting screw holes through the insertion holes 31 in a state in which the positions of the corresponding insertion holes 31 are aligned with the mounting screw holes of the bottom plate portion 12a of the carriage body 12 (screws). The head unit 17 is accommodated and fixed inside the carriage body 12. As described above, before the head unit 17 is permanently fixed to the carriage body 12, the position of the head unit 17 relative to the carriage body 12 and the posture such as the tilt are adjusted by the operation of the adjustment lever 20. Is done.

  The flow path member 24 attached to the upper part of the sub-carriage 26 is a box-shaped member with a thin vertical direction, and is made of, for example, a synthetic resin. The flow path member 24 is screwed to the upper end surface of each upright wall part 26b by a flow path fixing screw 45 so as to straddle the upper opening formed by the four upright wall parts 26b of the sub-carriage 26. Inside the flow path member 24, ink distribution flow paths (not shown) of respective colors corresponding to flow path connection portions 38 of sub tanks 37 (described later) of the recording heads 18 are formed. Ink of each color sent from the ink cartridge side through the ink supply tube 14 is introduced into each ink distribution channel. On the lower surface of the flow path member 24, a connection flow path 40 extending downward is provided at a position corresponding to the flow path connection portion 38 of the sub tank 37 of each recording head 18. The connection flow path 40 is a hollow cylindrical member in which a lead-out path (not shown) communicating with the corresponding color ink distribution flow path is formed. The connection flow path 40 is configured to be inserted into the flow path connection portion 38 of the sub tank 37 of each recording head 18 and connected in a liquid-tight state. Then, the ink that has passed through the ink distribution flow path inside the flow path member 24 is supplied to the sub tank 37 of each recording head 18 via the connection flow path 40 and the flow path connection portion 38.

  FIG. 9 is a simplified view of the lower surface side of the sub-carriage 26 (the surface on the nozzle forming surface 53 side of each recording head 18 and the side facing the recording medium during the recording operation). The dummy head 23 (described later) is not attached, and (b) shows the state where each recording head 18 and dummy head 23 are attached. A head insertion opening 28 (corresponding to the opening in the present invention) that is common to each recording head 18 is provided in a substantially central portion of the base portion 26a of the sub-carriage 26, through which a plurality of recording heads 18 can be inserted. The head insertion opening 28 in the present embodiment is a through hole having a rectangular shape in plan view. By forming the head insertion opening 28, the base portion 26a is a frame-like frame body composed of four sides. In addition, a total of five head mounting portions 41 a to 41 e are provided side by side in a direction corresponding to the main scanning direction on the lower surface of the base portion 26 a of the sub-carriage 26 in the present embodiment. That is, the sub-carriage 26 in the present embodiment is designed so that the five recording heads 18 can be attached. The head attachment portion 41 is an area (attachment position) where the recording head 18 or the dummy head 23 is fixed. Each head mounting portion 41 is provided with a fastening hole 29. The fixing hole 29 is a female screw portion having a threaded inner periphery, and is configured such that a fixing screw 27 described later is screwed. The fixing holes 29 are respectively formed on the side portions on both sides of the direction corresponding to the nozzle row direction (direction perpendicular to the head row setting direction) with the head insertion opening 28 interposed therebetween with respect to one head mounting portion 41. A total of four locations are provided, two in a row in the head row direction. These fixing holes 29 are formed at positions corresponding to a head screw hole 42 of the recording head 18 or a dummy head screw hole 43 of the dummy head 23 described later.

  In the following, the first recording head 18a, the second recording head 18b, the third recording head 18c, and the first recording head 18a will be described with respect to the sub-carriage 26 that is designed so that a maximum of five recording heads 18 can be attached. A case where a total of four recording heads 18 of the four recording heads 18d are attached will be described. Each recording head 18 is inserted into a receiving portion 35 by inserting a sub-tank 37 to be described later from below the head insertion opening 28 (the lower surface side of the base portion 26a), and the nozzle forming surface 53 of each recording head 18 is placed in the base portion 26a. Are fixed to the base portion 26a side by side in the main scanning direction (direction intersecting (preferably perpendicular to) the nozzle row direction) during the recording operation in a state of projecting below the lower surface of the recording medium (on the recording medium side during the recording operation). Is done. As described above, in the configuration in which a smaller number of recording heads 18 than the original attachable number are attached to the sub-carriage 26, only the difference in the head attaching portions 41 is provided. If no measures are taken with this configuration, a space is created in a portion corresponding to the head mounting portion 41. When such a space is generated, the rigidity of the sub-carriage 26 is correspondingly reduced as compared with the configuration in which the recording head 18 is attached to all the head attachment portions 41.

  In view of such a problem, in the head unit 17 according to the present invention, the head insertion opening is provided in each head mounting portion 41 (41a, 41b, 41d, 41e) other than the third head mounting portion 41c in the central portion of the sub-carriage 26. In addition, the recording head 18 is attached in a state of straddling the head 28, and the dummy head 23 is attached to the third head mounting portion 41c in the center so as to straddle the head insertion opening 28, thereby suppressing a decrease in rigidity of the sub-carriage 26. Yes. That is, the dummy head 23 functions as a reinforcing member that reinforces the sub-carriage 26. Details of the dummy head 23 will be described later.

FIG. 10 is a perspective view illustrating the configuration of the recording head 18 (a kind of liquid ejecting head). Since the basic structure and the like are common to the recording heads 18, one of the five recording heads 18 attached to the sub-carriage 26 is shown as a representative.
The recording head 18 includes a flow path unit that forms an ink flow path including a pressure chamber that communicates with the nozzle 51, and a pressure generating means such as a piezoelectric vibrator or a heating element that causes pressure fluctuations in the ink in the pressure chamber (both are shown in the figure). (Not shown) is provided in the head case 52. The recording head 18 applies a drive signal from the control unit side of the printer 1 to the pressure generating means to drive the pressure generating means, thereby ejecting ink from the nozzles 51 to land on a recording medium such as recording paper. It is configured to perform a recording operation. A plurality of nozzles 51 for ejecting ink are provided on the nozzle forming surface 53 of each recording head 18 to form a nozzle array 56 (a kind of nozzle group). The nozzle array 56 is arranged in a direction orthogonal to the nozzle array. It is formed side by side. One nozzle row 56 includes, for example, 360 nozzle openings opened at a pitch of 360 dpi. Ink flow paths, pressure generating means, and the like corresponding to each nozzle row 56 are individually provided, and different inks may be assigned to the two nozzle rows 56 of the same recording head 18 as described later.

  The head case 52 is a hollow box-like member that is short in the direction orthogonal to the nozzle row direction (main scanning direction during the recording operation) and long in the nozzle row direction. A flow path unit is fixed to the front end side of the head case 52 (side facing the recording medium during recording operation) with the nozzle forming surface 53 exposed. Further, pressure generating means and the like are accommodated in an accommodation space formed inside the head case 52, and ink is supplied to the flow path unit side on the base end surface side (upper surface side) opposite to the front end surface. A sub tank 37 is attached. Further, flange portions 52 a that protrude toward the side are formed on both sides in the nozzle row direction on the upper surface side of the head case 52. In each flange portion 52a, two head screw holes 42 are formed in a state of being aligned in a direction perpendicular to the nozzle row, corresponding to the fixing holes 29 provided in the head mounting portion 41 of the sub-carriage 26. . That is, two head screw holes 42 are formed in each flange portion 52a, and four head screw holes 42 are provided on one recording head 18 on both sides. The distance between the head screw holes 42 is matched to the distance between the fixing holes 29 of the head mounting portion 41. The inner diameter of the head screw hole 42 is set to be slightly larger than the inner diameter of the fixing hole 29, and a fixing screw 27 described later can be inserted.

  The sub tank 37 is a member that introduces ink from the flow path member 24 to the pressure chamber side of the recording head 18. The sub-tank 37 has a self-sealing function for controlling the introduction of ink into the pressure chamber side by opening and closing a valve in accordance with an internal pressure fluctuation. At both end portions in the nozzle row direction on the rear end surface (upper surface) of the sub tank 37, a flow path connection portion 38 to which the connection flow path 40 of the flow path member 24 is connected is provided. A ring-shaped packing (not shown) is fitted into the flow path connecting portion 38, and liquid tightness with the connection flow path 40 is ensured by this packing. Further, two drive boards (not shown) for supplying a drive signal to the pressure generating means are provided inside the sub tank 37, and two flexible cables 55 (electrically connected to each drive board) ( A kind of wiring member in the present invention is drawn out to the rear end face side of the sub tank 37. The flexible cable 55 is connected to the signal cable 15 and supplies a drive signal or the like sent from the control unit of the printer 1 through the signal cable 15 to the pressure generating means side through the drive board.

  FIG. 11 is a perspective view illustrating the configuration of the dummy head 23. The dummy head 23 is made integrally from, for example, a synthetic resin. The dummy head 23 is attached to the sub-carriage 26 so as to be adjacent to the outer side in the same direction with respect to the recording head 18 that is originally arranged at the end of the sub-carriage 26 in the head row direction. It is a protective member that protects the recording head 18 from recording paper or the like during operation. For this reason, dummy head attachment portions 44 to which the dummy heads 23 are attached are respectively provided on both sides of the sub-carriage 26 in the head row direction. In the present embodiment, the dummy head 23 is used as a reinforcing member for the sub-carriage 26 without being attached to the dummy head attachment portion 44. The dummy head 23 in the present embodiment is manufactured in a shape that follows the shape of the recording head 18. That is, each dimension of the dummy head 23 (the depth in the direction corresponding to the nozzle row direction, the width in the direction corresponding to the main scanning direction, the front end surface 65 (the surface on the side facing the recording medium during the recording operation) to the rear end surface ( The height) up to the upper surface on the side opposite to the front end surface 65 is aligned with the corresponding dimensions of the recording head 18. The dummy head attached to the dummy head attaching portion 44 has a shape having no rear end side (upper surface side) portion than a dummy head flange portion 57 described below.

  The dummy head 23 has flange portions (dummy head flange portions) 57 formed on both sides in the direction corresponding to the nozzle row direction, similarly to the recording head 18. The dimension in the width direction of the dummy head flange portion 57, the protruding length from the dummy head main body 58, and the thickness are aligned with the corresponding dimensions of the flange portion 52a. The vertical distance from the upper surface of the dummy head flange portion 57 (the surface on the side contacting the base portion 26 a of the sub-carriage 26) to the leading end surface 65 is from the upper surface of the flange portion 52 a of the recording head 18 to the nozzle forming surface 53. It is aligned to the vertical distance. Two dummy head screw holes 43 are formed in the dummy head flange portions 57 on both sides corresponding to the fixing holes 29 provided in the base portion 26a of the sub-carriage 26, respectively. That is, two dummy head screw holes 43 are formed in each dummy head flange portion 57. That is, the dummy head 23 is provided with four dummy head screw holes 43 on both sides. The inner diameter of each dummy head screw hole 43 is aligned with the inner diameter of the head screw hole 42 of the recording head 18 so that the fixing screw 27 can be inserted. The interval between the dummy head screw holes 43 is also the same as the interval between the head screw holes 42 of the recording head 18. The dummy head 23 configured in this way can be attached to the head attachment portion 41 of the sub-carriage 26. In other words, the attachment structure (structure such as a screw hole for fixing) of the recording head 18 to the head attachment portion 41 and the attachment structure of the dummy head 23 to the head attachment portion 41 are made common. In the state of being attached to the sub-carriage 26, the leading end surface 65 of the dummy head 23 is configured to be positioned on the same plane with respect to the nozzle forming surface 53 of the recording head 18 attached to the same sub-carriage 26. Yes. The positional relationship between the tip surface 65 of the dummy head 23 attached to the sub-carriage 26 and the nozzle forming surface 53 of the recording head 18 suffices if the dummy head 23 is designed to be aligned on the same surface. However, manufacturing or structural errors are allowed. In addition, the material of the dummy head 23 is not limited to the synthetic resin, and other materials such as metal can be adopted as long as the material has rigidity capable of reinforcing the sub-carriage 26.

  In the present embodiment, a plurality of suction nozzles 66 are provided on the front end surface 65 of the dummy head 23 along a direction corresponding to the nozzle row direction. The diameter of the suction nozzle 66 is set larger than the diameter of the nozzle 51 of the recording head 18. The suction nozzle 66 is configured to suck the mist in a state where the ink ejected from the nozzle 51 of the recording head 18 is drifting in the atmosphere without landing on the landing target such as recording paper during the recording operation. Yes. Inside the dummy head 23, suction channels 67 communicating with the respective suction nozzles 66 are respectively formed along the height direction of the dummy head. Each suction channel 67 is connected to one end of the drainage tube 68 on the rear end face side of the dummy head 23. The other end of the drainage tube 68 is connected to the above-described suction pump. By the operation of this suction pump, each suction flow path 67 is made negative pressure through the drainage tube 68, so that ink mist drifting in the atmosphere is sucked from the suction nozzle 66. Yes. The ink mist sucked from the suction nozzle 66 is discharged to the drainage tank through the suction channel 67 and the drainage tube 68. In the present embodiment, the configuration in which the mist suction function is provided to the dummy head 23 is illustrated, but the mist suction function may not be provided in the dummy head 23. Further, the shape of the dummy head 23 is not limited to that illustrated. At least, it can be attached to the head attachment portion 41 of the sub-carriage 26 without interfering with the other recording heads 18, and when attached to the sub-carriage 26, the tip surface is the nozzle forming surface 53 of the recording head 18. As long as they are located on the same plane, any shape can be adopted.

Next, the manufacturing process (assembly process) of the head unit 17 will be described.
First, the dummy head 23 is attached to the third head attachment portion 41c at the center of the sub-carriage 26 in the head row direction (dummy head attachment step). That is, the rear end side of the dummy head 23 is accommodated in the accommodating portion 35 from the lower surface side of the base portion 26a of the sub-carriage 26 through the head insertion opening 28, and the upper surface of the dummy head flange portion 57 is disposed on the frame portion of the base portion 26a. (The sides on both sides in the direction corresponding to the nozzle row direction) are brought into contact with each other. Then, the fixing screws 27 are screwed into the fixing holes 29 through the dummy head screw holes 43 in a state where the dummy head screw holes 43 are respectively aligned with the fixing holes 29 of the third head mounting portion 41 c. Thus, the dummy head 23 is fixed to the third head mounting portion 41c. As described above, when the dummy head 23 is first attached to the center portion of the sub-carriage 26, the dummy head 23 functions as a beam spanned across the head insertion opening 28, and the frame-shaped sub-carriage 26 is reinforced. Thereby, the deformation of the sub-carriage 26 due to the rotational moment when the remaining recording heads 18 are screwed to the sub-carriage 26 is suppressed.

  If the dummy head 23 is attached to the third head attachment portion 41c, the recording heads 18a to 18d are fixed in a state where they are positioned with respect to the corresponding head attachment portions 41 in the same procedure (heads). Installation process). In a state where the dummy head 23 and each recording head 18 are attached to the sub-carriage 26, as described above, the nozzle forming surface 53 of each recording head 18 and the leading end surface 65 of the dummy head 23 are located on the same surface. That is, the leading end surface 65 of the dummy head 23 is configured so as not to significantly protrude toward the recording medium side during the recording operation or to retreat significantly with respect to the nozzle forming surface 53 of each recording head 18. Yes. Each recording head 18 and dummy head 23 fixed to the sub-carriage 26 can be removed from the sub-carriage 26 by releasing the fastening screws 27. That is, each recording head 18 and dummy head 23 are detachably attached to the sub-carriage 26.

  If the dummy head 23 and each recording head 18 are attached to the subcarriage 26, then the flow path member 24 is fixed to the subcarriage 26 (flow path attaching process). As described above, the flow path member 24 is fixed to the sub-carriage 26 by the flow path fixing screw 45. At this time, the connection flow path 40 of the flow path member 24 is inserted into the flow path connection portion 38 of the sub tank 37 of each recording head 18 and connected in a liquid-tight state. Note that the flow path member 24 may be fixed to the sub-carriage 26 before each recording head 18 is attached to the sub-carriage 26.

  The head unit 17 is completed through the above steps. As described above, the head unit 17 is configured such that the nozzle forming surface 53 of each recording head 18 and the leading end surface of the dummy head 23 are exposed from the bottom opening 19 of the bottom plate portion 12a of the carriage body 12. The head unit 17 is housed inside and adjusted in posture, such as the position and inclination of the head unit 17 with respect to the carriage body 12, and then fixed by screwing with a head unit fixing screw 22.

As described above, in the configuration in which the number of the recording heads 18 attached to the sub-carriage 26 is smaller than the original attachable number (maximum attachable number), the third head attachment at the center of the sub-carriage 26 in the head row direction is provided. By attaching the dummy head 23 to the portion 41c, the dummy head 23 functions as a beam that passes over the center of the head insertion opening 28, and the frame-shaped sub-carriage 26 is reinforced. As a result, even when the number of the recording heads 18 attached to the sub-carriage 26 is smaller than the maximum attachable number, it is possible to prevent the rigidity of the sub-carriage 26 from being lowered. As a result, in a recording operation (printing operation) for recording an image or the like while relatively moving the head unit 17 and a recording medium such as recording paper, the recording medium such as the recording paper comes into contact with the recording head 18 or the like. The deformation of the sub-carriage 26 when an external force is applied to the head 26 is suppressed, and the relative position shift and the posture tilt of each recording head 18 are prevented. Therefore, if the number of recording heads 18 attached to the subcarriage 26 is increased or decreased by changing the specification within the range of the maximum mountable number, the subcarriage 26 can be shared without redesigning.
When the dummy head 23 and each recording head 18 are attached to the sub-carriage 26, as described above, the nozzle forming surface 53 of each recording head 18 and the tip surface 65 of the dummy head 23 are located on the same surface. Therefore, the recording medium comes into contact with the portion of the dummy head 23 protruding from the nozzle forming surface 53 in the recording operation, or the recording medium is formed in a space formed by the front end surface 65 retreating from the nozzle forming surface 53. It is prevented that paper jam occurs due to being caught.
Further, by attaching the dummy head 23 to the third head attachment portion 41c in the center of the sub-carriage 26 in the head row direction, the recording heads 18 are arranged symmetrically with the dummy head 23 interposed therebetween. As a result, even when the weight of the dummy head 23 is different from the weight of the recording head 18, the weight distribution in the head row arrangement direction of the sub-carriage 26 can be made symmetric from the center in the direction to both sides. As a result, when the recording operation is performed while the head unit 17 is reciprocated with respect to the recording medium, the posture of the head unit 17 can be stabilized.

  Further, since the dummy head 23 can be attached to and detached from the sub-carriage 26, for example, the dummy head 23 is temporarily removed from the sub-carriage 26 when the recording head 18 attached to the sub-carriage 26 is replaced or repaired. As a result, the operation of attaching and detaching the recording head 18 is facilitated, and the maintenance workability is improved. In addition, it is possible to easily cope with the case where the number of recording heads 18 attached to the sub-carriage 26 is increased or decreased by changing the specification within the range of the maximum mountable number.

  In addition, this invention is not limited to each above-mentioned embodiment, A various deformation | transformation is possible based on description of a claim.

  12A and 12B are schematic views for explaining the configuration of the second embodiment of the present invention. FIG. 12A is a sectional view of the sub-carriage 26 with the recording head 18 and the dummy head 23 attached, and FIG. FIG. 4 is a bottom view of the sub-carriage 26 in a state where the recording head 18 and the dummy head 23 are attached. As shown in FIG. 12B, the sub-carriage 26 of the present embodiment is provided with a total of seven head mounting portions 41a to 41g. That is, the sub-carriage 26 is designed so that a total of seven recording heads 18 can be attached. In the present embodiment, the recording heads 18a to 18d are respectively attached to the four head attaching portions 41b, 41c, 41e, and 41f of the sub-carriage 26, and the remaining three head attaching portions 41a, 41d, and 41g are respectively dummy. Heads 23a to 23c are attached. That is, the dummy carriages 23 are attached to the sub-carriage 26 in the present embodiment at three locations, the central portion in the head row direction and both ends in the head row direction, and the sub carriage 26 is reinforced by each dummy head 23. The

  Further, in the present embodiment, the rear end portions (portions on the upper surface side opposite to the front end surface) of the dummy heads 23a to 23c are connected to each other by a connecting portion 70 disposed along the head row direction. ing. Thereby, the rigidity of the sub-carriage 26 can be further increased. In particular, the connecting portion 70 increases the rigidity in the direction in which the heads are arranged, that is, in the direction corresponding to the main scanning direction, so that the recording paper or the like comes into contact with the recording head 18 in the recording operation. Deformation of the sub-carriage 26 when an external force in the main scanning direction is applied is more effectively suppressed. As a result, the displacement of the relative position of each recording head 18 and the inclination of the posture are prevented more reliably. Also in the present embodiment, as in the first embodiment, the nozzle formation surface 53 of each recording head 18 and the tip of each dummy head 23 in a state where the dummy head 23 and each recording head 18 are attached to the sub-carriage 26. The surface 65 is located on the same surface. In the configuration of the present embodiment, the dummy heads 23a and 23c attached to the both ends of the head array direction protect the side surfaces of the recording heads 18a and 18d adjacent to the center part side in the head array direction, respectively. It is more reliably prevented that the recording paper or the like comes into contact with the recording head 18 inside.

  FIG. 13 is a perspective view for explaining a modified example of the dummy head 23, and shows a state viewed from the front end surface side. The dummy head 23 in this modification is characterized in that the liquid absorbing material 72 is provided at least on the entire front end face 65. The liquid absorbing material 72 is made of a material that can absorb ink, such as sponge, and absorbs ink mist drifting in the atmosphere. Accordingly, the mist suction function can be provided to the dummy head 23 more easily and at a lower cost than the configuration of the first embodiment in which the mist is sucked from the suction nozzle 66 by the suction pump. Note that the front end surface 65 of the dummy head 23 is retracted toward the rear end surface side of the dummy head 23 by the thickness of the liquid absorbing material 72. As a result, the surface of the liquid absorbing material 72 of the dummy head 23 is positioned on the same plane as the nozzle forming surface 53 of each recording head 18 in a state of being attached to the sub-carriage 26. Further, the ink absorbed by the liquid absorbing material 72 can be discharged to the drainage tank side by operating the suction pump in a state where the leading end surface of the dummy head 23 is capped by the capping portion.

Note that the shape of the sub-carriage 26 as the head fixing member is not limited to a box-like shape having an open upper surface as exemplified in the above embodiments. The present invention is applicable to any frame-like head fixing member having a base portion 26a to which at least a plurality of recording heads 18 are attached and having four side portions in which openings related to the accommodation of the recording heads 18 are opened. Can be applied.
Further, the configuration and the number of the recording heads 18 attached to the sub-carriage 26 are not limited to those exemplified in the above embodiment.

  Furthermore, in each of the above-described embodiments, the configuration in which the ink is ejected while the recording head 18 is reciprocally moved with respect to the recording medium is exemplified, but the present invention is not limited thereto. For example, it is possible to employ a configuration in which ink is ejected while moving the recording medium with respect to the recording head 18 in a state where the position of the recording head 18 is fixed.

  In the above description, the ink jet printer 1 which is a type of liquid ejecting apparatus has been described as an example. However, the present invention includes a liquid ejecting head unit having a head fixing member to which a plurality of liquid ejecting heads are mounted. The present invention can also be applied to other liquid ejecting apparatuses. For example, a display manufacturing apparatus that manufactures color filters such as liquid crystal displays, an electrode manufacturing apparatus that forms electrodes such as organic EL (Electro Luminescence) displays and FEDs (surface emitting displays), and chips that manufacture biochips (biochemical elements) The present invention can also be applied to a manufacturing apparatus and a micropipette that supplies an accurate amount of a very small amount of sample solution.

  DESCRIPTION OF SYMBOLS 1 ... Printer, 3 ... Carriage, 12 ... Carriage body, 13 ... Carriage cover, 17 ... Head unit, 18 ... Recording head, 22 ... Head unit fixing screw, 23 ... Dummy head, 24 ... Channel member, 26 ... Subcarriage 27 ... Fastening screw, 28 ... Head insertion opening, 29 ... Fastening hole, 41 ... Head mounting portion, 42 ... Head screw hole, 43 ... Dummy head screw hole, 51 ... Nozzle, 52 ... Head case, 53 ... Nozzle formation Surface, 56 ... Nozzle row, 57 ... Dummy head flange, 58 ... Dummy head main body, 65 ... Tip surface, 66 ... Suction nozzle, 67 ... Suction flow path, 68 ... Drain tube, 70 ... Connection part, 72 ... Suction Liquid material

Claims (3)

A liquid ejecting head having a nozzle forming surface in which a nozzle for ejecting liquid to a landing target is established;
A head fixing member having a plurality of head mounting portions to which the liquid ejecting head is attached, and an opening through which the liquid ejecting head is inserted;
A protective member for protecting the liquid jet head attached to the head attachment portion from the landing target;
With
The protection member has a front end surface corresponding to the nozzle formation surface of the liquid ejecting head, and the front end surface is aligned on the same surface as the nozzle formation surface of the liquid ejecting head. A liquid ejecting head unit, wherein the liquid ejecting head unit is attached to a head attaching portion at a central portion in a head array direction so as to straddle the opening.   The liquid ejecting head unit according to claim 1, wherein the protection member is detachable from the central head mounting portion. A liquid ejecting head having a nozzle forming surface in which nozzles for ejecting liquid to a landing target are provided, and a plurality of head attaching portions to which the liquid ejecting head is attached, and the liquid ejecting head attached to the head attaching portion. A liquid ejecting head unit including a head fixing member formed with an opening to be inserted and a protective member protecting the liquid ejecting head attached to the head attaching portion from the landing target is mounted.
A liquid ejecting apparatus for ejecting liquid from the nozzles and causing the liquid ejecting head to land on the landing target while relatively moving the liquid ejecting head unit and the landing target in a head row arrangement direction;
The protection member has a front end surface corresponding to the nozzle formation surface of the liquid ejecting head, and the front end surface is aligned on the same surface as the nozzle formation surface of the liquid ejecting head. A liquid ejecting apparatus, wherein the liquid ejecting apparatus is attached in a state of straddling the opening to a head attaching part at a central part in a head row arranging direction.

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