JP2021186994A - Printer - Google Patents

Abstract

To suppress a scatter of ink mists caused by an influence of the cooling air of a platen.SOLUTION: A printer 1 comprises: printing heads 36a to 36d having nozzle faces 39b, discharging inks from nozzles arranged at the nozzle faces 39b, and printing a sheet S; a platen drum 30 arranged in a position opposing the nozzle face 39b; and a blowing part for making cooling air F for cooling the platen drum 30 flow in a width direction of the platen drum 30. When the printing heads 36a to 36d exist in printing positions Ta, one end of the nozzle face 39b of the platen drum 30 in the width direction is protruded to the outside of the platen drum 30, and a windproof plate 70b is arranged while opposing one end of the nozzle face 39b.SELECTED DRAWING: Figure 3

Description

The present invention relates to a printing apparatus.

Conventionally, a printing apparatus having a drum-shaped platen and adhering ink to a printing medium wound around the platen is known. In this type of printing apparatus, a hollow portion is provided in a drum, and cooling air is blown through the hollow portion to cool the platen (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-181083

In a configuration in which cooling air flows in the vicinity of a platen or the like as in the conventional printing apparatus, an air flow may be generated around the print head due to the influence of the cooling air. This air flow may cause ink mist floating in the printing apparatus to adhere to the nozzle surface. Therefore, it is necessary to perform maintenance on the print head and the like in consideration of the adhesion of ink mist due to this air flow.

One aspect for solving the above-mentioned problems is to have a nozzle surface, and to eject ink from a nozzle provided on the nozzle surface to print on a print medium, and to arrange the print head at a position facing the nozzle forming surface. The platen is provided with a blower portion for flowing the cooling air for cooling the platen in the width direction of the platen, and one end of the nozzle surface in the width direction of the platen when the print head is in the printing position. Is a printing device that protrudes to the outside of the platen and is provided with a windbreak plate facing one end of the nozzle surface.

The plan view which shows the schematic structure of the printing apparatus which concerns on embodiment of this invention. Side view of the main part of the printing device. Front view of the print head and platen drum. Side view of the main part of the printing module. Front view of the shading unit. A perspective view of a main part of a platen drum and a windbreak plate.

Hereinafter, the present embodiment will be described with reference to the drawings.
FIG. 1 is a plan view showing a schematic configuration of the printing apparatus 1 according to the present embodiment.
As shown in FIG. 1, the printing apparatus 1 includes a housing member 10 that constitutes the exterior of the printing apparatus 1. A working opening 12 having a door 11 is provided on one side surface of the housing member 10. The internal space of the housing member 10 is divided into a print area Ra and a maintenance area Rb by a flat plate-shaped frame member 81. As shown in FIG. 1 and each of the following figures, the longitudinal direction of the housing member 10 is the length direction of each member of the printing apparatus 1, and is indicated by reference numeral L. Further, the direction orthogonal to the direction L in the horizontal plane is defined as the width direction and is indicated by the symbol W.

The print area Ra is a space surrounded by the frame member 81 and the frame member 82 overlapping the side surface of the housing member 10. The print area Ra houses a printing unit 5 that prints on a print medium. The printing unit 5 is composed of a feeding unit 2, a process unit 3, and a winding unit 4. The feeding section 2, the process section 3, and the winding section 4 are arranged along the longitudinal direction of the housing member 10.

In this embodiment, the printing apparatus 1 exemplifies a configuration in which printing is performed on a long sheet S as a printing medium. The sheet S is made of high-quality paper, cast paper, art paper, coated paper, synthetic paper, polyethylene terephthalate, polypropylene and the like.

The feeding unit 2 has a feeding shaft 20 around which the sheet S before printing is wound. The sheet S is fed from the feeding shaft 20 and sent to the process unit 3 for printing by the process unit 3. The take-up unit 4 includes a take-up shaft 40 that winds up the printed sheet S. In FIG. 1 and each figure described later, the transport direction of the sheet S in the printing unit 5 is indicated by reference numeral Ds.

The process unit 3 has a platen drum 30 and a printing module 3U arranged to face the platen drum 30. The platen drum 30 is a cylindrical member, and a rotating shaft 302 is arranged at the center of the axis of the platen drum 30. The platen drum 30 is driven by a motor (not shown) and rotates about a rotation shaft 302. The sheet S unwound from the feeding shaft 20 is wound around the platen drum 30. As will be described later, the sheet S is in close contact with the outer peripheral surface 30a of the platen drum 30, and is conveyed toward the winding portion 4 as the platen drum 30 rotates.

The print module 3U has print heads 36w, 36a, 36b, 36c, 36d, ultraviolet irradiators 37a, 37b and the like, which will be described later with reference to FIG. The printing module 3U ejects ink to the sheet S and irradiates the ink with ultraviolet rays to form an image on the printed surface of the sheet S. The platen drum 30 supports the sheet S at a position facing the printing module 3U and conveys the sheet S.

The frame member 81 is provided with a notch at a position corresponding to the print module 3U, and the notch allows the print area Ra and the maintenance area Rb to communicate with each other. The print module 3U is movable between the print area Ra and the maintenance area Rb through the notch of the frame member 81. The position of the print module 3U in the print area Ra is defined as the print position Ta, and the position of the print module 3U in the maintenance area Rb is defined as the maintenance position Tb.

In the maintenance area Rb, a maintenance mechanism (not shown) for performing maintenance of the print heads 36w, 36a, 36b, 36c, 36d and the like included in the print module 3U is arranged. The maintenance mechanism includes, for example, an ink receiver that receives ink ejected by the print heads 36w, 36a, 36b, 36c, and 36d, and a blade that wipes the print heads 36w, 36a, 36b, 36c, and 36d. The print module 3U is located at the print position Ta when printing on the sheet S, and faces the platen drum 30. The print module 3U moves to the maintenance position Tb when performing maintenance such as flushing, cleaning, and wiping of the print heads 36w, 36a, 36b, 36c, and 36d. Further, when the printing apparatus 1 is not executing the printing operation, the printing module 3U is located at the maintenance position Tb. In this state, the print heads 36w, 36a, 36b, 36c, 36d are protected by a capping mechanism (not shown).

FIG. 2 is a side view of a main part of the printing apparatus 1. As shown in FIG. 2 and the following figures, the vertical direction in the installed state of the printing apparatus 1 is the height direction, and is indicated by reference numeral H. The height direction H is orthogonal to the L direction and the width direction W. Further, FIG. 2 shows the transport path of the sheet S from the feeding section 2 to the winding section 4 via the process section 3 with reference numerals Pc.

The sheet S unwound from the feeding portion 2 is wound around the driven roller 21, nipped into the pair of rollers 31 and 31n, and conveyed to the platen drum 30. The printing apparatus 1 has a roller 33 that abuts on the outer peripheral surface 30a of the platen drum 30. The roller 33 sandwiches the sheet S with the outer peripheral surface 30a, and brings the sheet S into close contact with the outer peripheral surface 30a.

The print module 3U includes print heads 36w, 36a, 36b, 36c, 36d arranged side by side along the outer peripheral surface 30a, and ultraviolet irradiators 37a, 37b. The print heads 36w to 36d and the ultraviolet irradiators 37a and 37b are supported by the support member 35. The support member 35 is an arch-shaped member arranged along the outer peripheral surface 30a. There is a gap between the support member 35 and the outer peripheral surface 30a, and this gap is indicated by reference numeral δ. The support member 35 has the tips of the print heads 36w, 36a, 36b, 36c, 36d and the ultraviolet irradiators 37a, 37b facing the outer peripheral surface 30a.

A roller 34 is arranged downstream of the platen drum 30 in the path Pc. The sheet S is wound around the roller 33 and the roller 34 so as to be in close contact with the outer peripheral surface 30a. The sheet S is conveyed toward the take-up shaft 40 by reversing the conveying direction by the roller 34. A pair of rollers 32, 32n, and a roller 41 for niping the sheet S are arranged between the roller 34 and the take-up shaft 40.

The five print heads 36w, 36a, 36b, 36c, and 36d are arranged side by side along the transport direction Ds and eject different inks. For example, the print head 36w ejects white ink, the print head 36a ejects yellow ink, the print head 36b ejects cyan ink, the print head 36c ejects magenta ink, and the print head 36d ejects black ink. The ink ejected by the print heads 36w, 36a, 36b, 36c, and 36d is a photocurable ink that is cured by irradiation with light. The ultraviolet irradiators 37a and 37b have an ultraviolet light source and irradiate the ink adhering to the sheet S with ultraviolet rays.

FIG. 3 is a front view of the print head 36d and the platen drum 30, and is a view seen from the downstream side in the transport direction Ds. In FIG. 3, for convenience of understanding, the ultraviolet irradiator 37b located downstream of the print head 36d is not shown. Further, the configurations of the print heads 36w, 36a, 36b, and 36c are the same as those of the print head 36d shown in FIG.

A nozzle for ejecting ink opens on the surface of the print head 36d facing the outer peripheral surface 30a. This surface is referred to as a nozzle forming surface 39a. A plurality of nozzles are arranged side by side along the width direction W on the nozzle forming surface 39a to form a nozzle row. The nozzle row has a width in which the print head 36d can print in the width direction W, and can print on a sheet S thinner than this width. In other words, the print head 36d has a nozzle row distributed in a range wider than the width of the sheet S on the nozzle forming surface 39a. The print heads 36w, 36a, 36b, and 36c also have a nozzle forming surface 39a facing the outer peripheral surface 30a, similarly to the print head 36d. A nozzle row composed of a plurality of nozzles is formed on each of the nozzle forming surfaces 39a of the print heads 36w, 36a, 36b, and 36c. The number of nozzle rows included in the print heads 36w, 36a, 36b, 36c, and 36d is arbitrary, and a plurality of nozzle rows may be arranged side by side along the length direction L.

A predetermined distance is secured between the nozzle forming surface 39a and the outer peripheral surface 30a. This interval is called a paper gap. At the time of printing, the sheet S and the nozzle row face each other with a paper gap, and the ink droplets ejected from the nozzles fly through the paper gap and land on the sheet S.

In order to form a nozzle row longer than the width of the sheet S on the print heads 36w, 36a, 36b, 36c, 36d, the size of the print heads 36w to 36d in the width direction W, that is, the width dimension of the print heads 36w to 36d. Is longer than the width dimension of the platen drum 30. Therefore, both ends of the print heads 36w to 36d in the width direction W project outward from the ends of the platen drum 30 in the width direction W.

The nozzle forming surface 39a projects from the tip of the print head 36d toward the platen drum 30. As shown in FIG. 3 and FIG. 6 described later, a head cover member 39 is attached to the tip of the print head 36d. The head cover member 39 is a box-shaped member whose upper portion is open, and is fitted into the tip of the print head 36d. An opening is formed along the width direction W on the lower surface side of the head cover member 39, and the nozzle forming surface 39a is exposed from this opening. That is, the head cover member 39 is a cover that covers a portion other than the nozzle forming surface 39a at the tip of the print head 36d. The nozzle forming surface 39a and the tip surface, which is the surface of the lower surface of the head cover member 39 facing the inner platen drum 30, are substantially flush with each other. Similar to the print head 36d, the head cover member 39 is also attached to the tips of the print heads 36w, 36a, 36b, and 36c. Therefore, the tips of the print heads 36w to 36d have a shape in which the nozzle forming surface 39a protrudes, but the step is filled by the head cover member 39, and the surface becomes a substantially flat surface.
The nozzle surface 39b refers to the lower end surface of the print head 36d. That is, the nozzle surface 39b is a surface including the nozzle forming surface 39a and the tip surface of the head cover member 39. The position of the boundary between the nozzle forming surface 39a and the tip surface of the head cover member 39 on the nozzle surface 39b may be appropriately determined according to the specifications of the printing apparatus 1.

Irradiation portions (not shown) for irradiating ultraviolet rays are formed at the tips of the ultraviolet irradiators 37a and 37b. The irradiation unit irradiates the entire region of the sheet S to which the ink has adhered with ultraviolet rays. Therefore, the width dimension of the irradiation portion is longer than the width dimension of the outer peripheral surface 30a. Therefore, the width dimension of the ultraviolet irradiator 37a and 37b is longer than the width dimension of the outer peripheral surface 30a, and both ends of the ultraviolet irradiator 37a and 37b in the width direction W project from both ends of the outer peripheral surface 30a in the width direction W. There is.

As described with reference to FIG. 1, the print module 3U is movable between the print position Ta and the maintenance position Tb. In order to enable this movement, the support member 35 is supported by two rails 351 extending in the width direction W, and moves in the width direction W along the rail 351.

The printing device 1 of the present embodiment includes a blower fan 51 and an exhaust fan 52. Specifically, the frame member 82 is provided with a plurality of blower fans 51, and the frame member 81 is provided with a plurality of exhaust fans 52.

A horizontal virtual plane including the center of the platen drum 30 in the height direction H is shown by reference numeral P30 in FIG. The blower fan 51 and the exhaust fan 52 are arranged below the virtual plane P30. The blower fan 51 blows air outside the housing member 10 to the hollow portion 300 of the platen drum 30. The exhaust fan 52 is arranged below the virtual plane P30. The exhaust fan 52 sucks the air in the hollow portion 300 of the platen drum 30 and exhausts it to the maintenance area Rb.

Therefore, the airflow flows from the hollow portion 300 of the platen drum 30 to the maintenance region Rb by the blower fan 51 and the exhaust fan 52 in the axial direction of the rotating shaft 302. This air flow flows on the inner peripheral side of the platen drum 30 and acts as a cooling air F for cooling the platen drum 30. The blower fan 51 and the exhaust fan 52 function as a blower portion through which the cooling air F flows, the blower fan 51 functions as a suction portion, and the exhaust fan 52 functions as a discharge portion.

FIG. 4 is a side view of a main part of the printing module 3U. More specifically, it is a view of the print heads 36w to 36d, the ultraviolet irradiators 37a and 37b, and the light shielding plate 70 as viewed from the width direction W. FIG. 5 is a front view of the light shielding unit 6.

As shown in FIGS. 3 and 4, the light-shielding unit 6 is arranged on the side of the platen drum 30 in the width direction W. The light-shielding unit 6 is located corresponding to the notch provided in the frame member 81, and is located between the platen drum 30 and the maintenance area Rb.

As shown in FIGS. 4 and 5, the light-shielding unit 6 has three fan-shaped light-shielding plates 61a, 61b, and 61c. The light-shielding plates 61a, 61b, 61c are arranged so as to form one fan shape, and the respective arcs of the light-shielding plates 61a, 61b, 61c form one arc. In other words, the light-shielding plates 61a, 61b, 61c are arranged side by side in the arrangement direction of the print heads 36w to 36d and the ultraviolet irradiators 37a, 37b, and the light-shielding plate 61b is located in the center of the arrangement direction, and the light-shielding plate 61a and the light-shielding plate 61a and the light-shielding plate 61b are arranged side by side. The plate 61c is located at the end in the arrangement direction.

The light-shielding plates 61a, 61b, 61c block the irradiation light emitted by the ultraviolet irradiators 37a, 37b, that is, the ultraviolet rays directed from the gap δ or the like toward the maintenance region Rb. The light-shielding plates 61a, 61b, 61c prevent the maintenance region Rb from being irradiated with ultraviolet rays, and can suppress the curing of the ink in the maintenance region Rb. The surface of the light-shielding plates 61a, 61b, 61c on the platen drum 30 side may be processed to suppress the reflectance of ultraviolet rays. For example, the surfaces of the light-shielding plates 61a, 61b, and 61c may be coated with a black matte coating. By this processing, it is preferable that the surfaces of the light-shielding plates 61a, 61b, 61c function as a low-reflector having a reflectance of, for example, 10% or less with respect to the ultraviolet rays irradiated by the ultraviolet irradiators 37a, 37b.

The light-shielding plate 61a is movably supported by the support member 62a in the direction indicated by the reference numeral Da in the drawing. Similarly, the light-shielding plate 61b is supported by the support member 62b so as to be movable in the direction indicated by the reference numeral Db. The light-shielding plate 61c is supported by the support member 62c so as to be movable in the direction indicated by the reference numeral Dc. When the light-shielding plates 61a, 61b, 61c move in the Da direction, the Db direction, and the Dc direction, respectively, the fan shape formed by the light-shielding plates 61a, 61b, 61c expands and contracts. That is, the light-shielding unit 6 changes its size by moving the light-shielding plates 61a, 61b, 61c.

The support members 62a, 62b, 62c are arranged at the center of the fan shape of the light shielding unit 6. The support member 62a fits into the groove cam 63 and moves in the Da direction together with the light-shielding plate 61a as the groove cam 63 rotates. Similarly, the support member 62b is fitted to the groove cam 63 and moves in the Db direction together with the light-shielding plate 61b as the groove cam 63 rotates. The support member 62c fits into the groove cam 63 and moves in the Dc direction together with the light-shielding plate 61c as the groove cam 63 rotates. By rotating the groove cam 63 in this way, the light-shielding plates 61a, 61b, and 61c are simultaneously moved, and the light-shielding unit 6 is expanded and contracted as a whole.

The groove cam 63 is connected to the rotating shaft 64, and the rotating shaft 64 is connected to the output shaft of the light-shielding plate motor 65. The rotating shaft 64 is rotated by the power of the light-shielding plate motor 65, and the light-shielding unit 6 is expanded and contracted. The light-shielding plate motor 65 can switch the rotation direction by a control device (not shown), and can switch between an operation of expanding the light-shielding unit 6 and an operation of reducing the light-shielding unit 6.

As described above, the printing module 3U can move in the width direction W through the notch provided in the frame member 81, and can move between the printing position Ta and the maintenance position Tb. Since the light-shielding unit 6 is located at a position corresponding to the notch of the frame member 81, when the print module 3U moves in the width direction W, the light-shielding unit 6 is reduced so as to avoid the print module 3U. That is, the light-shielding plates 61a, 61b, 61c move toward the rotation axis 64. As a result, the light-shielding plates 61a, 61b, 61c are lowered to a position where they do not overlap with the lower ends of the print heads 36w to 36d and the ultraviolet irradiators 37a, 37b, and the printing module 3U can be moved in the width direction W. This state is defined as the retracted state of the shading unit 6.

After the printing module 3U is stopped, the light-shielding unit 6 moves the light-shielding plates 61a, 61b, 61c to expand as a whole. The expanded state of the light-shielding unit 6 is called a normal position. The normal position is a position where the light blocking unit 6 can block the ultraviolet rays emitted by the ultraviolet irradiators 37a and 37b. The light-shielding unit 6 is in the normal position at least while the print module 3U is located at the print position Ta.

A windbreak plate 70b is provided on the light-shielding plate 61b. The windbreak plate 70b is a plate-shaped member fixed to the surface of the light-shielding plate 61b, and projects from the surface of the light-shielding plate 61b toward the platen drum 30. Similarly, the light-shielding plate 61a is provided with a windbreak plate 70a, and the light-shielding plate 61c is provided with a windbreak plate 70c.

The windbreak plate 70b is provided so that the upper surface of the windbreak plate 70b is substantially at the same position as the outer peripheral surface 30a in the normal direction of the outer peripheral surface 30a. In other words, the normal direction of the outer peripheral surface 30a can be said to be the height direction or the radial direction of the cylindrical platen drum 30.
As shown in FIG. 5, the windbreaker plate 70b is composed of three windbreakers 70b1, 70b2, and 70b3. The windbreakers 70b1, 70b2 and 70b3 are joined together to form one continuous plate. For example, one plate may be bent to form windbreakers 70b1, 70b2, 70b3. The windbreakers 70b1, 70b2, and 70b3 have different angles from each other, and the windbreaker plate 70b is arranged so as to draw an arc along the curved outer peripheral surface 30a as a whole.

Like the windbreak plate 70b, the windbreak plate 70a has a plurality of windbreak portions and is arranged so as to draw an arc along the outer peripheral surface 30a as a whole. The same applies to the windbreak plate 70c.

FIG. 6 is a perspective view of a main part of the platen drum 30 and the windbreak plate 70b. The windbreak plate 70b faces the protruding portion 36d1, which is a portion of the platen drum 30 that protrudes outward when the print head 36d is in the printing position.
The protrusion 36d1 includes a part of the nozzle surface 39b. Specifically, the protruding portion 36d1 includes a portion of the nozzle surface 39b that protrudes to the outside of the platen drum 30 and / or a portion of the tip surface of the print head 36d that is not covered by the head cover 39. The protrusion 36d1 is located closer to the maintenance region Rb than the outer peripheral surface 30a in the width direction W. In other words, the windbreak plate 70b is arranged at a position overlapping the protrusion 36d1 when viewed from the normal direction of the outer peripheral surface 30a. Further, the windbreak plate 70b faces the protruding portion 36d1 protruding from the platen drum 30 on the downstream side in the blowing direction of the cooling air F.

The lower surface of the protrusion 36d1 faces the space between the platen drum 30 and the light shielding unit 6. Therefore, the wind may be blown to the protruding portion 36d1 due to the influence of the cooling air F flowing through the inner peripheral side of the outer peripheral surface 30a, that is, the hollow portion 300 of the platen drum 30. This wind is, for example, an air flow that blows upward when a part of the cooling air F collides with the frame member 81 or the light-shielding unit 6, and may cause a wind toward the protrusion 36d1. Further, while the printing apparatus 1 is printing, an air flow is generated around the platen drum 30 as the platen drum 30 rotates. This airflow may also generate wind in the direction toward the protrusion 36d1.

The wind blown on the protrusion 36d1 may, for example, cause ink mist drifting in the printing apparatus 1 generated when ink droplets are ejected from the nozzle of the nozzle forming surface 39a to adhere to the protrusion 36d1. The ink mist adhering to the protrusion 36d1 may be dropleted and drips on the outer peripheral surface 30a of the platen drum 30, and may contaminate the outer peripheral surface 30a and the sheet S, and must be removed by maintenance. Therefore, if the adhesion of ink mist to the nozzle surface is promoted due to the influence of the cooling air F, it is necessary to take measures such as increasing the frequency of maintenance. In the printing apparatus 1 of the present embodiment, the windbreak plate 70b is located below the protrusion 36d1 to block or reduce the airflow toward the protrusion 36d1. This can be expected to have the effect of reducing the frequency of maintenance as a countermeasure against the dripping of ink mist in the protruding portion 36d1, reducing the time for stopping the printing device 1 for maintenance, and increasing the availability of the printing device 1.

In the configuration shown in FIG. 4, the windbreak plate 70b faces the protrusions 36d1 of the print heads 36a, 36b, 36c, and 36d, respectively. Therefore, also in the print heads 36a, 36b, 36c, the effect of blocking or reducing the wind hitting the protruding portion 36d1 by the windbreak plate 70b can be expected.

The windbreak plate 70a and the windbreak plate 70c also have the same effect as the windbreak plate 70b. As shown in FIG. 4, the windbreak plate 70a is arranged so as to face the front end surfaces of the print head 36w and the ultraviolet irradiator 37a. The windbreak plate 70c is arranged so as to face the tip surface of the ultraviolet irradiator 37b. Since the ultraviolet irradiators 37a and 37b are larger than the platen drum 30 in the width direction W like the print heads 36w to 36d, they project in the width direction W. The windbreak plates 70a and 70c block or reduce the airflow blown from below to the protrusion in the width direction W. This prevents or suppresses the adhesion of ink mist due to unintended airflow. For example, it is possible to suppress the adhesion of ink to the print head 36w and the ultraviolet irradiators 37a and 37b.

In the facing portion where the windbreak plate 70a and the windbreak plate 70b face each other, the end portion of the windbreak plate 70a and the end portion of the windbreak plate 70b overlap each other in the height direction H. Specifically, the windbreak portion 70b1 of the windbreak plate 70b is located above the end portion of the windbreak plate 70a. Similarly, in the facing portion where the windbreak plate 70b and the windbreak plate 70c face each other, the end portion of the windbreak plate 70b and the end portion of the windbreak plate 70c overlap each other in the height direction H. Specifically, the windbreak portion 70b3 of the windbreak plate 70b is located above the end portion of the windbreak plate 70c. Therefore, looking at the windbreak plates 70a, 70b, 70c in the radial direction from the rotation shaft 302 of the platen drum 30, the windbreak plates 70a, 70b, 70c are arranged without gaps. Therefore, the windbreak plates 70a, 70b, and 70c can more effectively attenuate the unintended airflow.

An ink receiving portion 90 is arranged below the windbreak plate 70a. The ink receiving portion 90 is located below the lowest position on the windbreak plate 70a. Further, the ink receiving portion 90 is also arranged below the windbreak plate 70c. The ink receiving portion 90 is located below the lowest position on the windbreak plate 70c. That is, in the region where the windbreak plates 70a, 70b, and 70c are arranged, the pair of ink receiving portions 90 are arranged corresponding to both ends in the length direction L.

The windbreak plates 70a, 70b, and 70c are arranged so as to form an arc as a whole, and the center in the length direction L is the highest and both ends are low. Therefore, when the ink mist adheres to the windbreak plates 70a, 70b, and 70c and becomes a droplet, the ink flows toward the end in the length direction L. For example, when ink adheres to the lower surface or the upper surface of the windbreak plate 70b, the ink flows toward the windbreak plate 70a or the windbreak plate 70c. The windbreaker 70b1 is above the windbreaker 70a, and the windbreaker 70b3 is above the windbreaker 70c. Therefore, ink flows from the windbreak plate 70b to the windbreak plate 70a and / or the windbreak plate 70c.

The ink adhering to the windbreak plate 70a and the windbreak plate 70c flows downward and drops downward. The dropped ink drops on the ink receiving portion 90. Therefore, the ink adhering to the windbreak plates 70a, 70b, and 70c can be collected in the ink receiving unit 90 without being scattered in the process unit 3.

Further, as shown in FIG. 6, the tip of the windbreak plate 70b is bent downward to form a bent portion 72b. The bent portion 72b is configured by bending the end portion of the windbreak plate 70b on the platen drum 30 side toward the rotation shaft 302, that is, in the normal direction of the outer peripheral surface 30a. The bent portion 72b has an effect of preventing the wind blown from below toward the protruding portion 36d1 from flowing in the direction toward the outer peripheral surface 30a. The bent portion 72b is formed in each of the windbreak portions 70b1, 70b2, and 70b3.

Further, the windbreak plate 70a and the windbreak plate 70c may have a configuration in which the bent portions 72a and 72c are formed, respectively, like the windbreak plate 70b.

As described above, the printing apparatus 1 of the present embodiment has the nozzle surface 39b, and the printing heads 36w, 36a, 36b, 36c that eject ink from the nozzles provided on the nozzle surface 39b and print on the sheet S. , 36d. The printing device 1 has a platen drum 30 arranged at a position facing the nozzle surface 39b, and a blower fan 51 and an exhaust fan as a blower portion for flowing cooling air F for cooling the platen drum 30 in the width direction of the platen drum 30. 52 is provided. When the print heads 36w, 36a, 36b, 36c, 36d are in the printing position, one end of the nozzle surface 39b in the width direction of the platen drum 30 protrudes to the outside of the platen drum 30 and protrudes from the platen drum 30. A windbreak plate 70b is provided so as to face one end of the nozzle surface 39b. As a result, when an airflow toward one end of the nozzle surface 39b protruding from the platen drum 30 is generated due to the influence of the cooling air F that cools the platen drum 30, this airflow is blocked or attenuated by the windbreak plate 70b. be able to. Therefore, the phenomenon that the ink mist adheres to the nozzle surface 39b can be suppressed or eliminated. Therefore, the effect of reducing the stains on each part caused by the adhered ink mist can be expected. This makes it possible to reduce the frequency of maintenance, for example, reduce the frequency and time for stopping the printing operation of the printing device 1, and increase the availability of the printing device 1.

In the printing apparatus 1, the windbreak plate 70b is provided so as to face one end of the nozzle surface 39b at a position corresponding to the protrusion 36d1. Downstream of the cooling air F, the cooling air F collides with the structure of the process unit 3 and the like, so that airflows in various directions are generated. Therefore, by arranging the windbreak plate 70b downstream of the cooling air F, it is possible to more effectively block or attenuate the airflow toward the nozzle surface 39b.

In the printing apparatus 1, the windbreak plate 70b includes a bent portion 72b extending along the end portion of the platen drum 30. As a result, the airflow flowing toward the platen drum 30 can be more effectively blocked or attenuated.

The printing apparatus 1 is provided with an ultraviolet irradiator 37a between the print heads 36w and 36a, and an ultraviolet irradiator 37b downstream of the print head 36d so as to face the platen drum 30. The ultraviolet irradiator 37a is adjacent to the print head 36w and the print head 36a, and the ultraviolet irradiator 37b is adjacent to the print head 36d. The width dimension of the ultraviolet irradiators 37a and 37b is formed longer than the width dimension of the platen drum 30. The windbreak plates 70a and 70c are provided so as to face the portions where the print head 36w and the ultraviolet irradiators 37a and 37b protrude from the platen drum 30. As a result, the airflow toward the portion of the print head 36w, the ultraviolet irradiator 37a, and 37b protruding from the platen drum 30 can be blocked or attenuated by the influence of the cooling air F. Therefore, it is possible to prevent the ink mist from adhering to the print head 36w and the ultraviolet irradiators 37a and 37b, and reduce the frequency of maintenance of the print head 36w and the ultraviolet irradiators 37a and 37b.

The printing apparatus 1 includes a plurality of printing heads 36w to 36d arranged along the transport direction of the sheet S, and a printing module 3U having ultraviolet irradiators 37a and 37b. The plurality of windbreak plates 70a, 70b, 70c are arranged side by side along the arrangement direction of the print heads 36w to 36d and the ultraviolet irradiators 37a, 37b. The plurality of windbreak plates 70a, 70b, 70c are arranged so that at least a part of the windbreak plates 70a, 70b, 70c overlaps at the facing portion where the adjacent windbreak plates 70a, 70b, 70c face each other. Since the airflow does not flow through the gaps between the plurality of windbreak plates 70a, 70b, and 70c, the adhesion of ink mist can be suppressed or eliminated more effectively.

In the printing apparatus 1, an ink receiving portion 90 that receives ink flowing down from the windbreak plates 70a and 70c is located below the windbreak plates 70a and 70c located at the ends in the arrangement direction of the print heads 36w to 36d and the ultraviolet irradiators 37a and 37b. It will be provided. Therefore, the ink adhering to the windbreak plates 70a and 70c can be recovered, and the ink can be prevented from scattering in an unintended direction. Further, since the windbreak plate 70b is located above the windbreak plates 70a and 70c, the ink adhering to the windbreak plate 70b can be collected in the ink receiving portion 90 through the windbreak plate 70a or the windbreak plate 70b.

The printing device 1 is arranged on the side of the print heads 36w to 36d and the ultraviolet irradiators 37a and 37b, and includes light-shielding plates 61a, 61b and 61c for blocking the synchrotron radiation of the ultraviolet irradiators 37a and 37b, and the light-shielding plates 61a and 61b. , 61c are attached with windbreak plates 70a, 70b, 70c. Therefore, the influence of the airflow colliding with the light-shielding plates 61a, 61b, 61c on the nozzle surface 39b can be effectively suppressed or eliminated.
Specifically, a windbreak plate 70b is attached to the light-shielding plate 61b located on the side of the print heads 36a to 36d. Windproof plates 70a and 70c are attached to the light-shielding plates 61a and 61c arranged on the sides of the print head 36w and the ultraviolet irradiators 37a and 37b, respectively. Therefore, the airflow to the print heads 36w to 36d and the airflow to the ultraviolet irradiators 37a and 37b can be effectively blocked or attenuated by the windbreak plates 70a, 70b and 70c.

The above-described embodiment exemplifies one aspect of the present invention, and can be arbitrarily modified and applied without departing from the spirit of the present invention.

For example, in the above-described embodiment, the configuration in which the windbreak plates 70a, 70b, 70c are attached to the light-shielding plates 61a, 61b, 61c has been exemplified, but the present invention is not limited thereto. The windbreak plates 70a, 70b, 70c may be attached to the frame member 81 or other structures.

Further, in the above-described embodiment, the size of the print heads 36w to 36d in the width direction W, that is, the width dimension of the print heads 36w to 36d is longer than the width dimension of the platen drum 30, and the width of the print heads 36w to 36d. Both ends in the direction W exemplify a configuration in which both ends of the platen drum 30 project outward from the ends of the platen drum 30 in the width direction W. The present invention is not limited to this, and for example, if the printing apparatus 1 is wider than the width of the printable sheet S, the width dimension of the print heads 36w to 36d may be shorter than the width dimension of the platen drum 30. Even in this case, if one end of the nozzle forming surface 39a of the print head protrudes to the outside of the platen drum 30 when the print head is in the printing position, the nozzle forming surface 39a is caused by the air flow toward one end of the nozzle forming surface 39a. It is possible to prevent the ink mist from adhering to the surface by using a windbreak plate, and the same effect as that of the above embodiment can be obtained.

Further, in the above-described embodiment, the configuration in which the platen drum 30 having a cylindrical shape is provided and the print heads 36w to 36d and the ultraviolet irradiators 37a and 37b are arranged along the outer peripheral surface 30a of the platen drum 30 is exemplified. The present invention is not limited to this, and may include, for example, a horizontally extended platen. In this case, the print heads 36w to 36d and the ultraviolet irradiators 37a and 37b are arranged side by side in the horizontal direction along the surface of the platen. Further, the light-shielding plates 61a, 61b, 61c are arranged along the arrangement direction of the print heads 36w to 36d and the ultraviolet irradiators 37a, 37b. In this configuration, if the windbreak plates 70a, 70b, and 70c are arranged along the extending direction of the platen, the same effect as that of the above embodiment can be obtained.

Further, the arrangement order of the print heads 36w to 36d and the ultraviolet irradiators 37a and 37b shown in the above embodiment, the transport path of the sheet S, and the like can be appropriately changed, and the configuration of the other printing device 1 can be appropriately changed. It can be changed.

1 ... printing device, 2 ... feeding section, 3 ... process section, 3U ... printing module, 4 ... winding section, 5 ... printing section, 6 ... shading unit, 10 ... housing member, 30 ... platen drum, 30a ... outer peripheral surface , 35 ... Support member, 36w, 36a, 36b, 36c, 36d ... Print head, 36d1 ... Projection, 37a, 37b ... Ultraviolet irradiator, 39 ... Head cover member, 39a ... Nozzle forming surface, 39b ... Nozzle surface, 40 ... Winding shaft, 41 ... Roller, 51 ... Blower fan (blower part), 52 ... Exhaust fan (blower part), 61a, 61b, 61c ... Shading plate, 62a, 62b, 62c ... Support member, 63 ... Groove cam, 64 ... Rotating shaft, 65 ... Shading plate motor, 70 ... Shading plate, 70a, 70b, 70c ... Windbreak plate, 70b1, 70b2, 70b3 ... Windproof part, 72a, 72b, 72c ... Bent part, 81, 82 ... Frame member, 90 ... Ink receiving part, 300 ... Hollow part, 302 ... Rotating shaft, 351 ... Rail, F ... Cooling air, S ... Sheet (printing medium).

Claims (7)

A printing head having a nozzle surface and ejecting ink from a nozzle provided on the nozzle surface to print on a printing medium.
A platen arranged at a position facing the nozzle surface and
A blower portion for flowing cooling air for cooling the platen in the width direction of the platen is provided.
When the print head is in the print position, one end of the nozzle surface in the width direction of the platen protrudes to the outside of the platen.
A printing device provided with a windbreak plate facing one end of the nozzle surface. The printing apparatus according to claim 1, wherein the windbreak plate is provided at one end of the nozzle surface, facing a portion protruding from the platen on the downstream side in the blowing direction of the cooling air. The printing apparatus according to claim 1 or 2, wherein the windbreak plate includes a bent portion extending along an end portion of the platen. An ultraviolet irradiator adjacent to the print head and facing the platen is provided.
The width dimension of the ultraviolet irradiator is formed longer than the width dimension of the platen.
The printing apparatus according to any one of claims 1 to 3, wherein the windbreak plate is provided so as to face a portion where the ultraviolet irradiator protrudes from the platen. A printing module having a plurality of the print heads arranged along the transport direction of the print medium and the ultraviolet irradiator is provided.
The windbreak plate includes a plurality of the windbreak plates arranged side by side along the arrangement direction of the print head and the ultraviolet irradiator.
The printing apparatus according to claim 4, wherein at least a part of the windbreak plates overlaps at the facing portion where the windbreak plates are opposed to each other. The printing apparatus according to claim 5, wherein an ink receiving portion for receiving ink flowing down from the windbreak plate is provided below the windbreak plate located at the end in the arrangement direction of the print head and the ultraviolet irradiator. A light-shielding plate arranged on the side of the print head and the ultraviolet irradiator and blocking the irradiation light of the ultraviolet irradiator is provided.
The printing apparatus according to claim 5 or 6, wherein the windbreak plate is attached to the light-shielding plate.

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