JP7512587B2 - Liquid ejection device - Google Patents

Description

The present invention relates to a liquid ejection device.

Conventionally, liquid ejection devices that print on a sheet by ejecting liquid are known. For example, Patent Document 1 discloses an image forming device equipped with a head moving means that moves a head unit in both directions along the sheet transport direction between a position corresponding to the transport means and a position corresponding to the maintenance and recovery means. The transport means transports the sheet, and the maintenance and recovery means maintains and recovers the recording head that is included in the head unit and ejects liquid.

Patent No. 5181686

The technology disclosed in Patent Document 1 mentions moving the head unit between a position corresponding to the transport means and a position corresponding to the maintenance and recovery means, but does not mention the positioning of the wiper that wipes the nozzle surface of the head unit. Furthermore, in conventional liquid ejection devices, there is a problem in that the nozzle surface of the head cannot be sufficiently wiped due to misalignment between the head and the wiper. One aspect of the present invention aims to sufficiently wipe the nozzle surface of the liquid ejection head by preventing misalignment between the liquid ejection head and the wiper.

In order to solve the above-mentioned problem, a liquid ejection device according to one aspect of the present invention includes a liquid ejection head having a nozzle surface on which nozzles for ejecting liquid are formed, a wiper for wiping the nozzle surface, a cap for covering the nozzles, a maintenance unit on which the wiper and the cap are mounted, a relative movement means for relatively moving the liquid ejection head and the maintenance unit in a first direction parallel to the nozzle surface and a second direction intersecting the nozzle surface, and a head positioning means for positioning the liquid ejection head and the cap, the head positioning means including a maintenance protrusion provided on one of the liquid ejection head and the maintenance unit, a fitting portion provided on the other of the liquid ejection head and the maintenance unit into which the maintenance protrusion fits, and a fitting portion provided on the other of the liquid ejection head and the maintenance unit, the head positioning means being arranged to move the liquid ejection head and the maintenance unit relative to each other in the first direction so that when the nozzle surface is wiped by the wiper, the head positioning means is arranged to position the liquid ejection head and the cap. and a wiper guide means for guiding a relative movement between the wiper and the liquid ejection head. When the wiper is caused to wipe the nozzle surface, the relative movement means positions the liquid ejection head and the maintenance unit at a first position in which the maintenance protrusion is disengaged from the fitting portion and at least a portion of the maintenance protrusion is positioned at the same position as at least a portion of the wiper guide means in the second direction. When the nozzle is covered by the cap, the relative movement means moves the liquid ejection head and the maintenance unit to a first position in which the maintenance protrusion is disengaged from the fitting portion and at least a portion of the maintenance protrusion is positioned at the same position as at least a portion of the wiper guide means in the second direction. The head and the maintenance unit are positioned at a second position where they are closer to each other in the second direction than at the first position and the maintenance protrusion fits into the fitting portion, and when separating the liquid ejection head, the cap, and the wiper, the relative movement means positions the liquid ejection head and the maintenance unit at a third position where the maintenance protrusion does not fit into the fitting portion and the maintenance protrusion is located at a different position from the wiper guide means in the second direction.

According to one aspect of the present invention, by preventing misalignment between the liquid ejection head and the wiper, the nozzle surface of the liquid ejection head can be wiped sufficiently.

1 is a schematic diagram illustrating a configuration of a liquid ejection device according to a first embodiment of the present invention. 2 is a schematic diagram showing the configuration of a liquid ejection head and a maintenance unit when maintenance is performed on the liquid ejection head included in the liquid ejection device shown in FIG. 1 . 3 is a schematic diagram showing a case where the liquid ejection head and the maintenance unit shown in FIG. 2 are in a position different from the position shown in FIG. 2 . 3 is a top perspective view showing a state in which the liquid ejection head and a maintenance unit shown in FIG. 2 face each other. FIG. 2 is a top perspective view showing the configuration of a liquid ejection head and a transport unit of the liquid ejection device shown in FIG. 1 during printing. 6 is a front view showing the configuration of the liquid ejection head and the transport unit shown in FIG. 5 . FIG. 10 is a bottom perspective view showing a state in which a liquid ejection head and a maintenance unit according to a second embodiment of the present invention face each other. FIG. 10 is a bottom perspective view showing the configuration of a liquid ejection head and a transport unit of a liquid ejection device according to a second embodiment of the present invention during printing.

[Embodiment 1]
<Configuration of liquid ejection device 1>
Fig. 1 is a schematic diagram showing the configuration of a liquid ejection device 1 according to a first embodiment of the present invention. As shown in Fig. 1, the liquid ejection device 1 includes a housing 10, a liquid ejection head 20, a maintenance unit 30, a drive unit 40, and a transport unit 50. The liquid ejection device 1 is a device that ejects liquid from the liquid ejection head 20 onto an ejection receiving medium S1 and fixes the liquid on the ejection receiving medium S1.

The liquid ejection device 1 is, for example, an inkjet label printer that prints on a label serving as the receiving medium S1. The liquid ejection device 1 is, for example, a line-head type printer in which the liquid ejection head 20 does not move relative to the receiving medium S1 during the printing process in a main scanning direction that is perpendicular to the transport direction DC described below and parallel to the nozzle surface 22 described below. However, the scope of application of the present invention is not limited to line-head type printers, and it is also applicable to serial type printers that print while moving a carriage carrying a liquid ejection head in the main scanning direction.

In the case of a serial type printer, the maintenance unit is placed outside the platen on which the receiving medium S1 is placed in the main scanning direction. In this case, no positioning is performed between the liquid ejection head and the transport unit. The housing 10 is an exterior member that houses each component inside. In FIG. 1 and the following description, the liquid ejection head 20 side is the upper side, and the transport unit 50 side is the lower side.

The ejection receiving medium S1 may be a sheet made of various materials. For example, the ejection receiving medium S1 may be paper, cloth, resin, nonwoven paper, wood, ceramic, semiconductor, metal, glass, or a composite of these. Sheet-like forms include those simply called sheets, as well as forms called paper, stickers, plates, foils, wafers, substrates, disks, films, and panels.

Furthermore, the scope of application of the present invention is not limited to liquid ejection devices that eject liquid onto a sheet-like ejection medium S1, but can also be applied to liquid ejection devices that eject liquid onto a case attached to a smartphone, fabric, or the like, as the ejection medium S1.

The liquid ejection head 20 is used to print on the receiving medium S1. The maintenance unit 30 performs maintenance on the liquid ejection head 20 to restore the ejection state of the multiple nozzles 21. The drive unit 40 drives the liquid ejection head 20 and the maintenance unit 30 to move. The transport unit 50 has rollers 45, 46, and transports the receiving medium S1 in the transport direction DC by the rollers 45, 46. The detailed configurations of the liquid ejection head 20, the maintenance unit 30, the drive unit 40, and the transport unit 50 will be described later.

When maintenance of the liquid ejection head 20 is not being performed, the maintenance unit 30 remains stationary at the retreat position P1. When maintenance of the liquid ejection head 20 is being performed, the downstream side of the transport unit 50 descends to the storage position P2, and the maintenance unit 30 moves to above the transport unit 50, which is stationary at the storage position P2. Then, the downstream side of the transport unit 50 rises to a position close to the liquid ejection head 20, and the maintenance unit 30 moves to the maintenance position P3 opposite the liquid ejection head 20.

When maintenance of the liquid ejection head 20 is completed, the downstream side of the transport unit 50 descends to the storage position P2, and the maintenance unit 30 returns to the retracted position P1. The downstream side of the transport unit 50 rises to a position close to the liquid ejection head 20. Then, the ejection medium S1 becomes ready for printing. Note that when the maintenance unit 30 returns to the retracted position P1, the entire transport unit 50 may descend to the storage position P2. In other words, the transport unit 50 may descend to the storage position P2 while remaining in a horizontal position.

The medium S1 to be ejected is unwound from roller 41. The medium S1 to be ejected is sandwiched between roller 43 and roller 44 via roller 42 and transported in the transport direction DC. Inside the housing 10, a transport unit 50 is disposed so as to face the liquid ejection head 20. As the medium S1 to be ejected is transported on the transport unit 50 by rollers 45 and 46, liquid is ejected from the liquid ejection head 20 onto the surface of the medium S1 to be ejected.

The transport unit 50 has a transport belt BE wound so as to be stretched between rollers 45 and 46. The transport unit 50 transports the ejection receiving medium S1 by adsorbing it to the transport belt BE. Examples of the adsorption method include an electrostatic adsorption method and an air adsorption method. In the electrostatic adsorption method, static electricity is generated on the surface of the transport belt BE to adsorb the ejection receiving medium S1 to the transport belt BE. In the air adsorption method, multiple through holes are formed in the transport belt BE, and air is sucked through the through holes to adsorb the ejection receiving medium S1 to the transport belt BE. It is also possible to simply place the ejection receiving medium S1 on the transport belt BE without adsorbing it to the transport belt BE.

Furthermore, the scope of application of the present invention is not limited to liquid ejection devices equipped with a transport unit having a transport belt BE. The present invention is also applicable to liquid ejection devices equipped with a transport unit that does not have a transport belt and in which a platen on which the ejection medium S1 is placed is provided between rollers 45, 46.

<Configuration when performing maintenance on liquid ejection head 20>
Fig. 2 is a schematic diagram showing the configuration of the liquid ejection head 20 and the maintenance unit 30 when performing maintenance on the liquid ejection head 20 included in the liquid ejection device 1 shown in Fig. 1. The diagram indicated by 101 in Fig. 2 is a front view showing the configuration of the liquid ejection head 20 and the maintenance unit 30, and the diagram indicated by 102 in Fig. 2 is a bottom view showing the configuration of the liquid ejection head 20 and the maintenance unit 30. In the diagram indicated by 102 in Fig. 2, the maintenance unit 30 is omitted, and the bottom 32A of the cap 32 is also omitted.

Also, FIG. 3 is a schematic diagram showing a case where the liquid ejection head 20 and maintenance unit 30 shown in FIG. 2 are in a position different from the position shown in FIG. 2. The view indicated by 201 in FIG. 3 shows a case where the liquid ejection head 20 and maintenance unit 30 are in a first position, which will be described later. The view indicated by 202 in FIG. 3 shows a case where the liquid ejection head 20 and maintenance unit 30 are in a third position, which will be described later. Note that the view indicated by 101 in FIG. 2 shows a case where the liquid ejection head 20 and maintenance unit 30 are in a second position, which will be described later.

As shown in FIG. 2, the liquid ejection head 20 has a nozzle surface 22 on which nozzles 21 for ejecting liquid are formed. Specifically, the liquid ejection head 20 is structured such that, for example, three heads 23 are provided on the lower surface of a resin holder H1. The heads 23 include nozzles 21. A plurality of nozzles 21 are formed in the nozzle surface 22 in a line along a direction perpendicular to the transport direction DC and perpendicular to the up-down direction.

The liquid ejection head 20 is not limited to this structure, and may, for example, have a structure consisting of a single head without a holder. The liquid ejection head 20 ejects liquid onto the ejection receiving medium S1. If the liquid ejection device 1 is, for example, an inkjet type image forming device, the liquid ejection head 20 is a recording head that ejects ink, and an image is formed on the ejection receiving medium S1 by fixing the ink. The liquid ejected from the liquid ejection head 20 is, for example, ink, but it may also be a liquid containing resin, a liquid containing metal, etc.

The liquid ejection device 1 further includes a rubber wiper 31 and a cap 32, and the maintenance unit 30 is equipped with the wiper 31 and the cap 32. The wiper 31 may be made of cloth. The wiper 31 extends along a direction perpendicular to the transport direction DC and perpendicular to the up-down direction. When maintenance of the liquid ejection head 20 is performed, the wiper 31 wipes the nozzle surface 22. The wiper 31 protrudes from the maintenance unit 30 so as to extend upward. The wiper 31 is disposed adjacent to the cap 32 in a first direction D1, which will be described later.

The cap 32 covers the nozzle 21 at a time separate from the time when the nozzle surface 22 is wiped. The cap 32 has a bottom 32A and a lip 32B. An annular lip 32B is provided on the outer periphery of the bottom 32A. The upper surface of the lip 32B comes into contact with the nozzle surface 22, and the nozzle 21 is surrounded by the lip 32B, so that the cap 32 covers the nozzle 21. Note that the upper surface of the lip 32B of the cap 32 may come into contact with the nozzle surface 22, or may come into contact with the lower surface of a frame provided on the head 23 so as to cover the edge of the nozzle surface 22, parallel to the nozzle surface 22.

A suction hole (not shown) is formed in the bottom 32A of the cap 32. When the suction hole is connected to a pump (not shown), the cap 32 covers the nozzle 21, and the pump is driven to reduce the pressure inside the cap 32 and perform a purging operation that forcibly expels ink from the nozzle 21. In addition, when printing is not being performed on the ejection medium S1, the cap 32 covers the nozzle 21 to prevent the nozzle 21 from drying out. Note that the cap 32 does not have to be connected to the pump, and may only have the function of covering the nozzle 21 to prevent the nozzle 21 from drying out.

Figure 4 is a top perspective view showing the liquid ejection head 20 and maintenance unit 30 shown in Figure 2 facing each other. The wiper 31 and cap 32 are omitted in Figure 4. The same applies to Figures 5 to 8. Note that Figure 4 shows the liquid ejection head 20 and maintenance unit 30 in a second position, which will be described later. The drive unit 40 moves the liquid ejection head 20 and maintenance unit 30 relative to each other in the first direction D1 and the second direction D2.

The first direction D1 is a direction parallel to the nozzle surface 22, and specifically may be the same direction as the transport direction DC, or may be the same direction as the opposite direction to the transport direction DC. The second direction D2 is a direction intersecting the nozzle surface 22, and specifically is a vertical direction or a direction inclined from the vertical direction. When the drive unit 40 moves the liquid ejection head 20 and the maintenance unit 30 relative to each other, it may move only either the liquid ejection head 20 or the maintenance unit 30, or it may move both the liquid ejection head 20 and the maintenance unit 30.

The drive unit 40 is an example of a relative movement means. The drive unit 40 is connected to each of the liquid ejection head 20 and the maintenance unit 30, and moves each of the liquid ejection head 20 and the maintenance unit 30 using a motor or the like (not shown).

The liquid ejection device 1 further includes a head positioning means 60. As shown in FIG. 4, the head positioning means 60 includes a maintenance protrusion 24, a fitting portion 33, and a wiper guide means 34. A plurality of maintenance protrusions 24 are provided on the lower surface of the holder H1 of the liquid ejection head 20, and protrude from the holder H1 so as to extend downward.

The maintenance protrusions 24 are provided on the lower surface of the holder H1 along the first direction D1. The number of maintenance protrusions 24 is, for example, four. The four maintenance protrusions 24 may be the same size. The wiper guide means 34 is provided on the upper surface of the maintenance unit 30.

The fitting portion 33 is provided on the maintenance unit 30. Specifically, the fitting portion 33 is provided in a groove portion 34A formed in the wiper guide means 34. The maintenance protrusion 24 fits into the fitting portion 33. When the maintenance protrusion 24 fits into the fitting portion 33, the head positioning means 60 positions the liquid ejection head 20 and the cap 32. The liquid ejection head 20 and the cap 32 can be fixed in position in the first direction D1 and in position in the direction D3 described below.

As shown in FIG. 4, the shape of the fitting portion 33 is cylindrical, but is not limited to this. For example, the shape of the fitting portion 33 may be a shape formed by two plate portions arranged in the groove portion 34A so as to be parallel to the direction D3. The height of the fitting portion 33 in the vertical direction from the bottom surface of the groove portion 34A is lower than the height from the bottom surface to the top surface of the groove portion 34A. The fitting portion 33 may be a hole with a bottom, or a through hole without a bottom.

When the drive unit 40 moves the liquid ejection head 20 and the maintenance unit 30 relative to each other in the first direction D1 so that the nozzle surface 22 is wiped by the wiper 31, the wiper guide means 34 guides the relative movement between the liquid ejection head 20 and the wiper 31.

The liquid ejection head 20 and the wiper 31 can be fixed in position in the direction D3, and the direction in which the nozzles 21 are arranged can be made to coincide with the extension direction of the wiper 31. The wiper guide means 34 extends along the first direction D1 and one end of the maintenance unit 30. The wiper guide means 34 is provided near one of the two ends of the maintenance unit 30 along the first direction D1.

It is preferable that the wiper guide means 34 extends downstream of the transport of the ejection medium S1 beyond the range where the maintenance protrusion 24 moves when the nozzle surface 22 is wiped by the wiper 31. This allows the maintenance protrusion 24 to remain inserted into the groove portion 34A even after the wiper 31 has finished wiping the nozzle surface 22, making it possible to stabilize the position of the liquid ejection head 20 relative to the maintenance unit 30.

As shown by 201 in FIG. 3, when the wiper 31 is caused to wipe the nozzle surface 22, the drive unit 40 positions the liquid ejection head 20 and the maintenance unit 30 at a first position. The first position is a position where the maintenance protrusion 24 is disengaged from the engagement portion 33, and where at least a portion of the maintenance protrusion 24 is positioned at the same position as at least a portion of the wiper guide means 34 in the second direction D2. This will be explained in detail below.

For example, consider a case where the liquid ejection head 20 is positioned at the second position described below. In this case, the drive unit 40 raises the liquid ejection head 20 along the second direction D2. This disengages the maintenance protrusion 24 from the fitting portion 33. Also, at least a portion of the maintenance protrusion 24 is positioned at the same position as at least a portion of the wiper guide means 34 in the second direction D2. Specifically, when the two maintenance protrusions 24 are inserted into the groove portion 34A, at least a portion of the two maintenance protrusions 24 overlap with at least a portion of the wiper guide means 34 when viewed from the direction D3 perpendicular to the first direction D1 and the up-down direction.

The drive unit 40 moves the maintenance unit 30 in the first direction D1. As a result, the wiper 31 moves in the first direction D1 while in contact with the nozzle surface 22, wiping the nozzle surface 22. By wiping the nozzle surface 22 with the wiper 31, the meniscus of the nozzle 21 can be adjusted.

When the wiper 31 wipes the nozzle surface 22, the drive unit 40 may move the liquid ejection head 20 in the first direction D1 instead of the maintenance unit 30. The drive unit 40 may also move the maintenance unit 30 and the liquid ejection head 20 along the first direction D1.

As shown by 101 in FIG. 2, when the cap 32 is to cover the nozzle 21, the driving unit 40 positions the liquid ejection head 20 and the maintenance unit 30 at a second position. The second position is a position where they are closer to each other in the second direction D2 than the first position, and where the maintenance protrusion 24 fits into the fitting portion 33. This will be described in detail below.

The drive unit 40 moves the maintenance unit 30 to a position where the nozzle 21 is surrounded by the lip 32B when viewed from below. The drive unit 40 then lowers the liquid ejection head 20. As a result, the liquid ejection head 20 and the maintenance unit 30 are closer to each other in the second direction D2 than they are at the first position, and the maintenance protrusion 24 fits into the fitting portion 33. As the maintenance protrusion 24 fits into the fitting portion 33, the cap 32 comes into a state where it covers the nozzle 21.

In this manner, when the cap 32 covers the nozzle 21, the drive unit 40 moves both the liquid ejection head 20 and the maintenance unit 30, but is not limited to this. When the cap 32 covers the nozzle 21, the drive unit 40 may move only one of the liquid ejection head 20 and the maintenance unit 30.

As shown by 202 in FIG. 3, when the liquid ejection head 20 is separated from the cap 32 and wiper 31, the drive unit 40 positions the liquid ejection head 20 and the maintenance unit 30 in a third position. The third position is a position where the maintenance protrusion 24 is not engaged with the engagement portion 33, and where the maintenance protrusion 24 is located at a different position from the wiper guide means 34 in the second direction D2. This will be described in detail below.

For example, consider a case where the liquid ejection head 20 is positioned at the second position. In this case, the drive unit 40 raises the liquid ejection head 20. This causes the maintenance protrusion 24 to no longer engage with the engagement portion 33. Furthermore, the maintenance protrusion 24 is positioned at a different position from the wiper guide means 34 in the second direction D2. Specifically, when viewed from the direction D3, the maintenance protrusion 24 does not overlap with the wiper guide means 34.

In this way, when separating the liquid ejection head 20 from the cap 32 and the wiper 31, the drive unit 40 moves only the liquid ejection head 20, but this is not limited to the above. When separating the liquid ejection head 20 from the cap 32 and the wiper 31, the drive unit 40 may move only the maintenance unit 30, or may move both the liquid ejection head 20 and the maintenance unit 30. If the operation of causing the wiper 31 to wipe the nozzle surface 22 and the operation of causing the cap 32 to cover the nozzle 21 are not performed, the operation of separating the liquid ejection head 20 from the cap 32 and the wiper 31 is performed.

As described above, when the nozzle 21 is covered by the cap 32 in the second position, the liquid ejection head 20 and the cap 32 can be positioned. Furthermore, when the nozzle surface 22 is wiped by the wiper 31 due to the relative movement from the first position, it is possible to prevent misalignment between the liquid ejection head 20 and the wiper 31. Therefore, the nozzle 21 can be sealed by the cap 32 to reduce drying of the liquid inside the nozzle 21, and the nozzle surface 22 can be wiped sufficiently.

<Configuration of Liquid Ejection Apparatus 1 During Printing Execution>
Fig. 5 is a top perspective view showing the configuration of the liquid ejection head 20 and the transport unit 50 when the liquid ejection device 1 shown in Fig. 1 is executing printing. Fig. 6 is a front view showing the configuration of the liquid ejection head 20 and the transport unit 50 shown in Fig. 5. The liquid ejection device 1 further includes a transport positioning means 70. As shown in Figs. 5 and 6, the transport positioning means 70 has a maintenance protrusion 24 and a transport guide means 51.

The transport guide means 51 is provided on the upper surface of the transport unit 50. Specifically, the transport guide means 51 is provided on the upper surface of the transport unit 50 that is not moved by the rollers 45, 46, that is, on a portion other than the transport surface along which the ejection medium S1 is transported. For example, the transport guide means 51 is provided on a bearing that supports the rollers 45, 46. The transport surface is parallel to the nozzle surface 22.

The transport guide means 51 extends along the first direction D1 and one end of the transport unit 50. The transport guide means 51 is provided near one of the ends of the transport unit 50 along the first direction D1. A support portion 52 is provided near the other end of the transport unit 50 along the first direction D1. Two of the four maintenance protrusions 24 come into contact with the support portion 52. As a result, the support portion 52 supports the two maintenance protrusions 24.

A groove 51A is formed in the transport guide means 51. When the liquid ejection device 1 is performing printing, the maintenance protrusion 24 is inserted into the groove 51A. The bottom surface of the groove 51A serves as a positioning surface 51B. In this way, the transport unit 50 has a positioning surface 51B.

When the maintenance protrusion 24 comes into contact with the positioning surface 51B, the transport positioning means 70 positions the transport unit 50 and the liquid ejection head 20. The transport guide means 51 also guides the relative movement between the liquid ejection head 20 and the transport unit 50. With this configuration, liquid can be appropriately ejected onto the ejection medium S1 transported by the transport unit 50 without misalignment between the position of the ejection medium S1 and the position of the liquid ejection.

Furthermore, the distance between the liquid ejection head 20 and the transport unit 50 can be fixed, and the positions of the liquid ejection head 20 and the transport unit 50 in the direction D3 can be fixed. Also, the direction in which the multiple nozzles 21 are arranged can be made to coincide with the direction D3.

A spring (not shown) may be provided on the upper surface of the holder H1 of the liquid ejection head 20. The spring is an example of a biasing means that biases the liquid ejection head 20 downward so that the maintenance protrusion 24 contacts the positioning surface 51B. When the wiper 31 wipes the nozzle surface 22, the maintenance protrusion 24 is disengaged from the fitting portion 33, so the force of the spring is not applied to the maintenance unit 30, and the maintenance unit 30 can move. When the cap 32 is made to cover the nozzle 21, the spring biases the liquid ejection head 20 downward so that the maintenance protrusion 24 fits into the fitting portion 33.

As shown in FIG. 4, the wiper guide means 34 has a groove portion 34A in which a fitting portion 33 is formed. A guide protrusion 25 shown in FIG. 6 is provided on the holder H1 of the liquid ejection head 20. The guide protrusion 25 is inserted into the groove portion 34A shown in FIG. 4 together with the maintenance protrusion 24 in the first position. The guide protrusion 25 is for guiding the relative movement between the liquid ejection head 20 and the wiper 31.

According to the above configuration, the maintenance protrusion 24 and the guide protrusion 25 are inserted into the groove 34A formed in the wiper guide means 34, which enables the wiper guide means 34 to guide the relative movement between the liquid ejection head 20 and the wiper 31.

As mentioned above, the maintenance protrusion 24 is not only for positioning the liquid ejection head 20 and the cap 32, but also for positioning the transport unit 50 and the liquid ejection head 20. When the maintenance protrusion 24 or the guide protrusion 25 comes into contact with the positioning surface 51B, the transport guide means 51 positions the transport unit 50 and the liquid ejection head 20.

As shown in FIG. 6, the length of the guide protrusion 25 in the vertical direction is shorter than the length of the maintenance protrusion 24 in the vertical direction. In this case, the maintenance protrusion 24 comes into contact with the positioning surface 51B. Conversely, the length of the maintenance protrusion 24 in the vertical direction may be shorter than the length of the guide protrusion 25 in the vertical direction. In this case, the guide protrusion 25 comes into contact with the positioning surface 51B.

The length of the guide protrusion 25 in the vertical direction may be the same as the length of the maintenance protrusion 24 in the vertical direction. In this case, the height of the positioning surface that contacts the guide protrusion 25 from the top surface of the transport unit 50 is different from the height of the positioning surface that contacts the maintenance protrusion 24 from the top surface of the transport unit 50. This causes the maintenance protrusion 24 or the guide protrusion 25 to contact the positioning surface.

According to the above configuration, the maintenance protrusion 24 or the guide protrusion 25 comes into contact with the positioning surface 51B. Therefore, compared to when both the maintenance protrusion 24 and the guide protrusion 25 come into contact with the positioning surface 51B, it is possible to prevent the liquid ejection head 20 from tilting relative to the transport unit 50 due to the difference in the length of the protrusions, since one of the protrusions does not come into contact with the positioning surface 51B.

The liquid ejection device 1 further includes a spring SR shown in FIG. 5. The spring SR connects a frame (not shown) of the housing 10 to the transport unit 50. The spring SR is an example of a biasing means that biases the transport unit 50 in a direction D4 that is perpendicular to the transport direction DC and parallel to the nozzle surface 22.

With the above configuration, the transport unit 50 is biased by the spring SR in a direction D4 perpendicular to the transport direction DC of the ejection medium S1 and parallel to the nozzle surface 22, so that the transport unit 50 can be positioned and misalignment between the position of the ejection medium S1 and the position of the liquid ejection can be prevented.

[Embodiment 2]
A second embodiment of the present invention will be described below. For ease of explanation, the same reference numerals are used for members having the same functions as those described in the first embodiment, and the description thereof will not be repeated. Fig. 7 is a bottom perspective view showing a state in which a liquid ejection head 20A and a maintenance unit 30A according to the second embodiment of the present invention face each other.

In embodiment 2, as shown in FIG. 7, the head positioning means 60A has a maintenance protrusion 35, a fitting portion 26, and a wiper guide means 27. A plurality of maintenance protrusions 35 are provided on the upper surface of the maintenance unit 30A, and protrude from the maintenance unit 30A so as to extend upward.

The maintenance protrusions 35 are provided on the upper surface of the maintenance unit 30A along the first direction D1. The number of maintenance protrusions 35 is, for example, four. The four maintenance protrusions 35 may be the same size. The wiper guide means 27 is provided on the lower surface of the holder H2 of the liquid ejection head 20A.

The fitting portion 26 is provided on the liquid ejection head 20A. Specifically, the fitting portion 26 is provided in a groove portion 27A formed in the wiper guide means 27. The maintenance protrusion 35 fits into the fitting portion 26. When the maintenance protrusion 35 fits into the fitting portion 26, the head positioning means 60A positions the liquid ejection head 20A and the cap 32 mounted on the maintenance unit 30A. The maintenance unit 30A is also provided with the aforementioned guide protrusion 25.

Figure 8 is a bottom perspective view showing the configuration of the liquid ejection head 20A and the transport unit 50A when the liquid ejection device according to the second embodiment of the present invention is performing printing. In the second embodiment, as shown in Figure 8, the transport positioning means 70A has a fitting portion 26, a wiper guide means 27, and a transport protrusion 53.

The transport protrusions 53 are provided on the upper surface of the transport unit 50A and protrude from the transport unit 50A so as to extend upward. The transport protrusions 53 are provided on the upper surface of the transport unit 50A along the first direction D1. The number of transport protrusions 53 is, for example, four. The four transport protrusions 53 may be the same size.

The wiper guide means 27 not only guides the relative movement between the liquid ejection head 20A and the wiper 31 mounted on the maintenance unit 30A, but also guides the relative movement between the liquid ejection head 20A and the transport unit 50A.

The wiper guide means 27 is provided near one of the ends of the holder H2 of the liquid ejection head 20A in the first direction D1. A support portion 28 is provided near the other end of the holder H2 in the first direction D1. Two of the four transport protrusions 53 come into contact with the support portion 28. As a result, the support portion 28 supports the two transport protrusions 53.

As described above, in the configurations of embodiment 1 and embodiment 2, the maintenance protrusion is provided on one of the liquid ejection head and the maintenance unit, and the fitting portion and wiper guide means are provided on the other of the liquid ejection head and the maintenance unit. In addition, the guide protrusion 25 is provided on the liquid ejection head 20 or the maintenance unit 30A.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. The technical scope of the present invention also includes embodiments obtained by appropriately combining the technical means disclosed in the different embodiments.

REFERENCE SIGNS LIST 1 Liquid ejection device 20, 20A Liquid ejection head 21 Nozzle 22 Nozzle surface 24, 35 Maintenance protrusion 25 Guide protrusion 26, 33 Fitting portion 27, 34 Wiper guide means 27A, 34A, 51A Groove portion 30, 30A Maintenance unit 31 Wiper 32 Cap 40 Driving portion 50, 50A Transport unit 51 Transport guide means 51B Positioning surface 53 Transport protrusion 60, 60A Head positioning means 70, 70A Transport positioning means D1 First direction D2 Second direction S1 Discharge receiving medium SR Spring

Claims (6)

a liquid ejection head having a nozzle surface on which nozzles for ejecting liquid are formed;
a wiper that wipes the nozzle surface;
A cap for covering the nozzle;
a maintenance unit that mounts the wiper and the cap;
a relative movement unit that moves the liquid ejection head and the maintenance unit relatively in a first direction parallel to the nozzle surface and in a second direction intersecting the nozzle surface;
a head positioning means for positioning the liquid ejection head and the cap;
A transport unit that transports the ejection receiving medium;
a transport positioning unit that performs positioning of the transport unit and the liquid ejection head,
The head positioning means includes:
a maintenance protrusion provided on one of the liquid ejection head and the maintenance unit;
a fitting portion provided on the other of the liquid ejection head and the maintenance unit, into which the maintenance protrusion is fitted;
a wiper guide means that is provided on the other of the liquid ejection head and the maintenance unit and that guides the relative movement between the liquid ejection head and the wiper when the nozzle surface is wiped by the wiper by moving the liquid ejection head and the maintenance unit relatively in the first direction,
The transport positioning means is
the wiper guide means provided on the liquid ejection head;
a conveying protrusion provided on the conveying unit,
the wiper guide means also guides relative movement between the liquid ejection head and the transport unit;
When the wiper is caused to wipe the nozzle surface, the relative movement means positions the liquid ejection head and the maintenance unit at a first position in which the maintenance protrusion is disengaged from the fitting portion and at least a portion of the maintenance protrusion is positioned at the same position as at least a portion of the wiper guiding means in the second direction;
When the nozzles are covered by the cap, the relative movement means positions the liquid ejection head and the maintenance unit at a second position where the liquid ejection head and the maintenance unit are closer to each other in the second direction than at the first position and the maintenance protrusion is fitted into the fitting portion;
A liquid ejection device characterized in that, when separating the liquid ejection head from the cap and the wiper, the relative movement means positions the liquid ejection head and the maintenance unit at a third position in which the maintenance protrusion does not engage with the engagement portion and the maintenance protrusion is positioned at a different position from the wiper guide means in the second direction. a liquid ejection head having a nozzle surface on which nozzles for ejecting liquid are formed;
a wiper that wipes the nozzle surface;
A cap for covering the nozzle;
a maintenance unit that mounts the wiper and the cap;
a relative movement unit that moves the liquid ejection head and the maintenance unit relatively in a first direction parallel to the nozzle surface and in a second direction intersecting the nozzle surface;
a head positioning means for positioning the liquid ejection head and the cap;
A transport unit that transports the ejection receiving medium;
a transport positioning unit that performs positioning of the transport unit and the liquid ejection head,
The head positioning means includes:
a maintenance protrusion provided on one of the liquid ejection head and the maintenance unit;
a fitting portion provided on the other of the liquid ejection head and the maintenance unit, into which the maintenance protrusion is fitted;
a wiper guide means that is provided on the other of the liquid ejection head and the maintenance unit and that guides the relative movement between the liquid ejection head and the wiper when the nozzle surface is wiped by the wiper by moving the liquid ejection head and the maintenance unit relatively in the first direction,
the transport positioning means includes the maintenance protrusion provided on the liquid ejection head and a transport guide means provided on the transport unit,
When the wiper is caused to wipe the nozzle surface, the relative movement means positions the liquid ejection head and the maintenance unit at a first position in which the maintenance protrusion is disengaged from the fitting portion and at least a portion of the maintenance protrusion is positioned at the same position as at least a portion of the wiper guiding means in the second direction;
When the nozzles are covered by the cap, the relative movement means positions the liquid ejection head and the maintenance unit at a second position where the liquid ejection head and the maintenance unit are closer to each other in the second direction than at the first position and the maintenance protrusion is fitted into the fitting portion;
when separating the liquid ejection head from the cap and the wiper, the relative movement means positions the liquid ejection head and the maintenance unit at a third position in which the maintenance protrusion is not engaged with the engagement portion and is located at a position different from the wiper guiding means in the second direction;
The liquid ejection apparatus according to claim 1, wherein the transport guide means guides relative movement between the liquid ejection head and the transport unit. a liquid ejection head having a nozzle surface on which nozzles for ejecting liquid are formed;
a wiper that wipes the nozzle surface;
A cap for covering the nozzle;
a maintenance unit that mounts the wiper and the cap;
a relative movement unit that moves the liquid ejection head and the maintenance unit relatively in a first direction parallel to the nozzle surface and in a second direction intersecting the nozzle surface;
a head positioning unit for positioning the liquid ejection head and the cap,
The head positioning means includes:
a maintenance protrusion provided on one of the liquid ejection head and the maintenance unit;
a fitting portion provided on the other of the liquid ejection head and the maintenance unit, into which the maintenance protrusion is fitted;
a wiper guide means that is provided on the other of the liquid ejection head and the maintenance unit and that guides the relative movement between the liquid ejection head and the wiper when the nozzle surface is wiped by the wiper by moving the liquid ejection head and the maintenance unit relatively in the first direction,
The wiper guide means has a groove in which the fitting portion is formed ,
When the wiper is caused to wipe the nozzle surface, the relative movement means positions the liquid ejection head and the maintenance unit at a first position in which the maintenance protrusion is disengaged from the fitting portion and at least a portion of the maintenance protrusion is positioned at the same position as at least a portion of the wiper guiding means in the second direction;
When the nozzles are covered by the cap, the relative movement means positions the liquid ejection head and the maintenance unit at a second position where the liquid ejection head and the maintenance unit are closer to each other in the second direction than at the first position and the maintenance protrusion is fitted into the fitting portion;
when separating the liquid ejection head from the cap and the wiper, the relative movement means positions the liquid ejection head and the maintenance unit at a third position in which the maintenance protrusion is not engaged with the engagement portion and is located at a position different from the wiper guiding means in the second direction;
A liquid ejection device characterized in that the liquid ejection head or the maintenance unit is provided with a guide protrusion that is inserted into the groove together with the maintenance protrusion at the first position and guides relative movement between the liquid ejection head and the wiper . Further comprising a transport unit that transports the ejection receiving medium,
The transport unit has a positioning surface,
The liquid ejection device described in claim 3, characterized in that the maintenance protrusion is also for positioning the transport unit and the liquid ejection head, and the maintenance protrusion or the guide protrusion contacts the positioning surface to position the transport unit and the liquid ejection head. the transport unit transports the ejection receiving medium in a transport direction;
5. The liquid ejection device according to claim 1, further comprising a biasing unit that biases the transport unit in a direction perpendicular to the transport direction and parallel to the nozzle surface. a liquid ejection head having a nozzle surface on which nozzles for ejecting liquid are formed;
a wiper that wipes the nozzle surface;
A cap for covering the nozzle;
a maintenance unit that mounts the wiper and the cap;
a relative movement unit that moves the liquid ejection head and the maintenance unit relatively in a first direction parallel to the nozzle surface and in a second direction intersecting the nozzle surface;
a head positioning unit for positioning the liquid ejection head and the cap,
The head positioning means includes:
a maintenance protrusion provided on one of the liquid ejection head and the maintenance unit, the maintenance protrusion extending in a direction intersecting with the nozzle surface;
a fitting portion provided on the other of the liquid ejection head and the maintenance unit, into which the maintenance protrusion is fitted;
a wiper guide means that is provided on the other of the liquid ejection head and the maintenance unit and that guides the relative movement between the liquid ejection head and the wiper when the nozzle surface is wiped by the wiper by moving the liquid ejection head and the maintenance unit relatively in the first direction,
When the wiper is caused to wipe the nozzle surface, the relative movement means positions the liquid ejection head and the maintenance unit at a first position in which the maintenance protrusion is disengaged from the fitting portion and at least a portion of the maintenance protrusion is positioned at the same position as at least a portion of the wiper guiding means in the second direction;
When the nozzles are covered by the cap, the relative movement means positions the liquid ejection head and the maintenance unit at a second position where the liquid ejection head and the maintenance unit are closer to each other in the second direction than at the first position and the maintenance protrusion is fitted into the fitting portion;
A liquid ejection device characterized in that, when separating the liquid ejection head from the cap and the wiper, the relative movement means positions the liquid ejection head and the maintenance unit at a third position in which the maintenance protrusion does not engage with the engagement portion and the maintenance protrusion is positioned at a different position from the wiper guide means in the second direction.

Images