WO2015146235A1

WO2015146235A1 - Inkjet recording device

Info

Publication number: WO2015146235A1
Application number: PCT/JP2015/051218
Authority: WO
Inventors: 荒川　裕明
Original assignee: コニカミノルタ株式会社
Priority date: 2014-03-25
Filing date: 2015-01-19
Publication date: 2015-10-01
Also published as: JPWO2015146235A1

Abstract

　This device is provided with: a first guide part (74) having a guide surface (74a) for guiding a flow of air towards the front edge of a recording head (71), along the direction of rotation of an image formation drum (50), and introducing the flow into a gap between the recording head (71) and the image formation drum (50); a second guide part (75) having a guide surface (75a) for guiding the flow of air introduced into the gap between the recording head (71) and the image formation drum (50), in a direction away from the outside peripheral surface of the image formation drum (50); and a mist recovery part (76) having an introduction port (76a) into which the flow of air guided by the second guide part (75) is introduced, for recovering the ink component contained in the flow of air introduced into the introduction port (76a).

Description

Inkjet recording device

The present invention relates to an ink jet recording apparatus.

Image formation using ink of an ink jet recording method or the like can form a high-definition image with a relatively simple configuration, and its application is expanding in various ways.
The inkjet recording apparatus includes an image forming drum that conveys the recording medium along the outer peripheral surface thereof, a supply unit that supplies the recording medium at a predetermined supply position of the image forming drum, and an image forming drum. 2. Description of the Related Art There is known a recording head that includes a recording head that forms an image by discharging ink onto a transported recording medium.

In such an ink jet recording apparatus, apart from ink droplets (main droplets) for landing on the recording medium, sub-droplets (satellite) that may be ejected together with the main droplets and these ink droplets are not required. A fine mist-like ink mist is generated.

Further, in the ink jet recording apparatus provided with the image forming drum, for example, as shown in FIG. 9, an air flow is generated on the surface of the image forming drum 1050 by the rotation of the image forming drum 1050 along the conveyance direction F of the recording medium. This is because resistance force (shear stress) is generated between the image forming drum 1050 and the air due to the rotation of the image forming drum 1050 due to the viscosity of air as a fluid. As a result, the closer to the outer peripheral surface of the image forming drum 1050, the higher the air flow velocity. When this air flow collides with the front side wall of the recording head 1071, it flows down along this wall surface and intersects with the air flow along the outer peripheral surface of the image forming drum 1050 at the introduction point A, so that a turbulent flow region is generated.

Therefore, in the vicinity of the ink discharge area B where the ink droplets are discharged facing the nozzle formation area 1071p where the nozzle row is formed, an unstable air flow mixed with this turbulent flow is generated. When ink droplets are ejected from the nozzles in this state, the main droplets are sufficiently affected by the air flow because the mass and initial velocity at the time of ejection are sufficient, and land on the desired position on the recording medium relatively stably. However, satellites and ink mist are affected by the air flow, and this turbulent flow causes noise to land on the recording medium, causing deterioration in image quality, or adhering to the nozzle surface and causing poor discharge. It may cause.

After that, at the derivation point C, the air pressure suddenly decreases in the vicinity of the rear side wall of the recording head 1071, and the Karman vortex may be generated on the wall surface side of the recording head 1071 rather than the boundary layer D. For this reason, the rear side wall of the recording head 1071 is soiled by satellites or ink mist, which is not preferable.

Therefore, for example, a guide surface is formed by cutting out the front edge and the rear edge in the scanning direction of the recording head to form a guide surface, and the air flow in the gap between the recording medium and the recording head caused by the scanning of the recording head. It has been studied to control (for example, Patent Documents 1 and 2).

JP 2011-218626 A JP 2002-103595 A

However, the recording head described in Patent Document 1 has a shape in which only the leading edge is cut out, and the air flow in the gap between the recording medium and the recording head can be controlled, but the pressure drop in the gap leading portion is reduced. Therefore, the generation of Karman vortices in the vicinity of the rear side wall of the recording head cannot be suppressed, and the air flow may diffuse in the lead-out portion and contaminate surrounding members. There is.

In addition, since the recording head described in Patent Document 2 has a configuration in which the trailing edge is cut out in a tapered shape in addition to the leading edge, generation of Karman vortices in the vicinity of the trailing side wall of the recording head can be suppressed. However, since the air flow diffuses at the part where the gap between the recording medium and the recording head is led, the problem of fouling surrounding members cannot be solved.

An object of the present invention is to stabilize the air flow in the gap between the recording medium conveyed by the image forming drum and the recording head to prevent unnecessary ink from adhering to the recording medium and the nozzle surface, and to derive from the gap. It is an object of the present invention to provide an ink jet recording apparatus capable of preventing the recording head and surrounding members from being contaminated by suppressing the diffusion of the air flow containing unnecessary ink.

In order to solve the above problems, the invention described in claim 1 is an ink jet recording apparatus that performs recording on a recording medium by discharging ink,
An image forming drum that conveys the recording medium by holding and rotating the recording medium on an outer peripheral surface;
A recording head provided at a position away from the outer peripheral surface of the image forming drum by a predetermined distance and having a nozzle surface in which a plurality of nozzles for ejecting ink are arranged along a direction intersecting the rotation direction of the image forming drum;
The air flow toward the upstream front edge of the recording head in the rotation direction of the image forming drum is guided in the direction along the rotation direction of the image forming drum and introduced into the gap between the recording head and the image forming drum. A first guide portion having a guide surface;
A second guide portion having a guide surface for guiding an air flow derived from a gap between the recording head and the image forming drum in a direction away from the outer peripheral surface of the image forming drum;
A recovery portion that has an inlet for introducing an airflow guided by the second guide portion, and that recovers an ink component contained in the airflow introduced into the inlet;
It is provided with.

The invention according to claim 2 is an ink jet recording apparatus that performs recording on a recording medium by discharging ink,
An image forming drum that conveys the recording medium by holding and rotating the recording medium on an outer peripheral surface;
A plurality of nozzles for ejecting ink has a recording head arranged along a direction intersecting the rotation direction of the image forming drum, and the nozzle of the image forming drum is located at a predetermined distance from the outer peripheral surface of the image forming drum. A plurality of head units arranged in parallel along the rotation direction;
The head unit is configured to guide an air flow toward a front edge portion of a head unit provided on the most upstream side in the rotation direction of the image forming drum among the plurality of head units in a direction along the rotation direction of the image forming drum. And a first guide portion having a guide surface to be introduced into a gap between the image forming drum and the image forming drum,
Among the plurality of head units, an air flow derived from a gap between the head unit provided on the most downstream side in the rotation direction of the image forming drum and the image forming drum is away from the outer peripheral surface of the image forming drum. A second guide part having a guide surface for guiding;
A recovery portion that has an inlet for introducing an airflow guided by the second guide portion, and that recovers an ink component contained in the airflow introduced into the inlet;
It is provided with.

The invention according to claim 3 is the ink jet recording apparatus according to claim 2,
The plurality of head units are arranged at predetermined intervals from each other,
A lid member that closes gaps between the plurality of head units is provided.

The invention according to claim 4 is the ink jet recording apparatus according to claim 2 or 3,
The recording head is provided so as to protrude from a surface of the head unit facing the image forming drum,
And a guide member that guides an airflow that enters the gap between the head unit and the outer peripheral surface of the image forming drum and flows down in the vicinity of the front edge and the rear edge of the recording head.

The invention according to claim 5 is the ink jet recording apparatus according to any one of claims 2 to 4,
The head unit includes a plurality of the recording heads arranged in parallel from the upstream side to the downstream side in the rotation direction of the image forming drum,
A closing member for closing gaps between the plurality of recording heads arranged side by side is provided.

The invention according to claim 6 is the ink jet recording apparatus according to any one of claims 1 to 5,
The first guide portion is characterized in that the guide surface is formed such that the distance from the outer peripheral surface of the image forming drum gradually decreases from the upstream side to the downstream side in the rotation direction of the image forming drum. To do.

The invention according to claim 7 is the inkjet recording apparatus according to claim 6,
In the first guide portion, the guide surface has a bullet shape so that an angle formed by a tangent line of the guide surface and a tangent line of the outer peripheral surface of the image forming drum decreases as the distance from the outer peripheral surface of the image forming drum increases. It is characterized by.

The invention according to claim 8 is the inkjet recording apparatus according to any one of claims 1 to 7,
The second guide portion has the guide surface formed such that the distance from the outer peripheral surface of the image forming drum gradually increases from the upstream side to the downstream side in the rotation direction of the image forming drum. To do.

The invention according to claim 9 is the ink jet recording apparatus according to claim 8,
The guide surface of the second guide portion is bullet-shaped so that an angle formed by a tangent line of the guide surface and a tangent line of the outer peripheral surface of the image forming drum increases as the distance from the outer peripheral surface of the image forming drum increases. It is characterized by.

The invention according to claim 10 is the inkjet recording apparatus according to any one of claims 1 to 9,
The collection unit is provided such that the introduction port is continuously arranged on a guide surface of the second guide unit.

The invention according to claim 11 is the inkjet recording apparatus according to any one of claims 1 to 10,
The recovery unit includes a discharge port for discharging the airflow introduced from the introduction port to a predetermined position.

The invention according to claim 12 is the ink jet recording apparatus according to any one of claims 1 to 11,
The introduction port is directed in a direction along a guide surface of the second guide portion.

The invention according to claim 13 is the ink jet recording apparatus according to any one of claims 1 to 12,
The collection unit includes a filter through which an air flow introduced from the introduction port passes, and collects the ink component contained in the air flow introduced into the introduction port by the filter.

The invention according to claim 14 is the ink jet recording apparatus according to any one of claims 1 to 13,
The collection unit includes an intake unit for intake of an airflow introduced from the introduction port.

The invention according to claim 15 is the ink jet recording apparatus according to claim 13,
The recovery part has an intake part for taking in the airflow introduced from the introduction port, and the intake part is arranged downstream of the filter in the flow-down direction of the airflow introduced from the introduction port. It is characterized by.

According to the present invention, the air flow in the gap between the recording medium conveyed by the image forming drum and the recording head is stabilized to prevent unnecessary ink from adhering to the recording medium and the nozzle surface, and derived from the gap. It is possible to prevent the recording head and surrounding members from being stained by suppressing the diffusion of the air flow containing unnecessary ink.

It is a figure which shows the main structures of an inkjet recording device. It is a perspective view of an image forming drum. It is a figure which shows the internal structure of a head unit. It is a figure which shows the internal structure of a head unit. FIG. 4 is a perspective view showing a positional relationship between an image forming drum and a cleaning unit and positions before and after movement of a head unit. FIG. 3B is an AA cross-sectional enlarged view in FIG. 3B. It is a figure explaining the shape of the 1st guide part. It is a figure which shows the external appearance structure of the head unit in another embodiment of this invention. It is the elements on larger scale of the head unit in FIG. It is a figure explaining the motion of the airflow in the conventional inkjet recording device.

Hereinafter, an ink jet recording apparatus according to an embodiment of the present invention will be described with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples. In addition, in the following description, what has the same function and structure attaches | subjects the same code | symbol, and abbreviate | omits the description.

As shown in FIG. 1, the inkjet recording apparatus 1 includes, for example, a paper feed unit 10, an image forming unit 20, and a paper discharge unit 30. The ink jet recording apparatus 1 transports the recording medium P stored in the paper feeding unit 10 to the image forming unit 20, forms an image on the recording medium P by the image forming unit 20, and discharges the recording medium P on which the image is formed. The paper is discharged onto the paper unit 30.

[Paper Feeder]
The paper feed unit 10 includes a paper feed tray 11 that stores the recording medium P, and a transport unit 12 that transports the recording medium P from the paper feed tray 11 to the image forming unit 20.
The paper feed tray 11 is a plate-like member provided so that a plurality of recording media P cut into a standard size can be placed in a stacked state. The paper feed tray 11 is provided so as to move up and down according to the amount of the recording medium P placed on the paper feed tray 11, and the uppermost recording medium P is transported by the transport unit 12 in the vertical movement direction. Held at a position.
The transport unit 12 includes a transport mechanism that transports the recording medium P on the belt 123 by driving a ring-shaped belt 123 that is stretched by a plurality of (for example, two)

rollers

121 and 122, and a paper feed tray 11. A supply unit that transfers the uppermost recording medium P placed thereon onto the belt 123 is provided. The transport unit 12 transports the recording medium P transferred from the supply unit onto the belt 123 so as to follow the belt 123.

[Configuration of image forming unit]
The image forming unit 20 uses the image forming drum 50 as a conveying device that holds the recording medium P along a cylindrical outer peripheral surface, and the recording medium P conveyed by the conveying unit 12 of the paper feeding unit 10 to the image forming drum 50. The transfer unit 22, the first heater 91 for heating the recording medium P held on the image forming drum 50, and a plurality of head mechanisms for forming an image by ejecting ink onto the recording medium P held on the image forming drum 50 As a head unit 70, a cleaning unit 60 (see FIG. 4) that receives ink ejected from the head unit 70 during maintenance of the head unit 70, and an energy beam for curing the ink ejected onto the recording medium P are irradiated. The irradiation unit 93 and the recording medium P irradiated with the irradiation unit 93 are received from the image forming drum 50 and conveyed to the paper discharge unit 30. Conveying mechanism 96, and a second heater 94 or the like for heating the outer peripheral surface of the directly imaging drum 50 without using the recording medium P.

[Image forming unit: Image forming drum]
As shown in FIG. 2, the image forming drum 50 functioning as a recording medium transport unit includes a claw unit 51 and an intake unit 52 for holding the recording medium P on its outer peripheral surface, and has a predetermined transport direction F (FIG. 1 (counterclockwise).
The image forming drum 50 has three recording medium P holding areas obtained by dividing the outer peripheral surface into three equal parts. That is, the image forming drum 50 can hold a total of three recording media P.
As shown in FIG. 2, the claw portion 51 has a plurality of claws provided along the rotation axis direction (X direction) of the cylindrical image forming drum 50 at a predetermined position on the outer peripheral surface of the image forming drum 50. . The claw portion 51 sandwiches the vicinity of one side of the recording medium P in cooperation with the outer peripheral surface of the image forming drum 50.
As shown in FIG. 2, the air intake portion 52 includes a plurality of air intake holes provided on the outer peripheral surface of the image forming drum 50 along the recording medium P sandwiched by the claw portion 51 in the vicinity of one side, and the air intake holes. And a suction force generator (not shown) (for example, an air pump or a fan) that generates a suction force so as to suck the gas into the image forming drum 50. In other words, the suction unit 52 sucks the recording medium P along the outer peripheral surface of the image forming drum 50 by the suction force generated by the suction from the suction hole.

[Image forming part: Delivery unit]
The delivery unit 22 is provided at a position interposed between the conveyance unit 12 of the paper feeding unit 10 and the image forming drum 50. The delivery unit 22 includes a claw portion 221 that sandwiches one end of the recording medium P transported by the transport unit 12, a cylindrical delivery drum 222 that guides the recording medium P sandwiched by the claw portion 221, and the like. The recording medium P on the portion 12 is picked up by the claw portion 221 and is along the outer peripheral surface of the transfer drum 222, so that the recording medium P is guided to the direction along the outer peripheral surface of the image forming drum 50 and transferred to the image forming drum 50. .

[Image forming unit: first heater]
The first heater 91 is a lamp heater made of, for example, a non-contact type halogen lamp that irradiates infrared rays, and the irradiation light from the lamp heater is uniformly perpendicular to the outer peripheral surface of the image forming drum 50. A reflecting plate is provided to efficiently irradiate and heat the outer peripheral surface of the image forming drum 50.
The first heater 91 is located on the outer peripheral surface of the image forming drum 50 on the downstream side in the transport direction with respect to the supply position described above, and on the upstream side in the transport direction with respect to each head unit 70. That is, the first heater 91 is provided to heat the recording medium P before image formation on the outer peripheral surface of the image forming drum 50.

A temperature sensor 92 is provided in the vicinity of the first heater 91 and on the downstream side in the transport direction. As the temperature sensor 92, a contact-type temperature detection element such as a thermocouple or a thermistor may be used, but a non-contact type temperature detection element such as a thermopile is more preferable.
The first heater 91 is controlled based on the temperature detected by the temperature sensor 92 so that the recording medium P held by the image forming drum 50 and passed through the vicinity of the first heater 91 has a predetermined temperature.

[Image forming unit: head unit]
FIG. 3A is a schematic diagram of an internal configuration when the head unit 70 is viewed from the side. FIG. 3B is a schematic diagram of the internal configuration when the head unit 70 is viewed from above. Here, “upper” means a direction opposite to the one side (lower surface) side of the head unit 70 facing the outer peripheral surface of the image forming drum 50, which is the lower side of the head unit 70. Moreover, the case where it sees from a side shows the case where the head unit 70 is seen by making one side surface of the head unit 70 in alignment with the up-down direction and X direction of the head unit 70 into the front.
The head unit 70 is juxtaposed in the order of magenta (M), cyan (C), black (K), and yellow (Y) from the upstream side in the transport direction along the transport direction F of the recording medium P by the image forming drum 50. ing. Each of these colors has different spectral absorption characteristics. Among the head units 70 of each color, the head unit 70 closest to the irradiation unit 93 on the most downstream side has the four colors. Among them, yellow ink, which has a spectral absorption characteristic with the lowest visual density, is ejected.

Since the structure of the head unit 70 for each color is the same, only one head unit 70 will be described.
The head unit 70 is provided at a position away from the image forming drum 50 by a predetermined distance, and is disposed along the outer peripheral surface of the image forming drum 50.
3A and 3B, the head unit 70 includes a plurality of recording heads 71, an ink tank 72 that stores ink to be supplied to each recording head 71, and an illustration that leads from the ink tank 72 to each recording head 71. And an ink heater 73 for adjusting the temperature of the ink before ejection by heating in the ink path not to be discharged.

The recording head 71 has a nozzle surface 71f (see FIG. 5) on which a plurality of nozzles 711 arranged in a direction intersecting the conveyance direction F of the recording medium. In the present embodiment, a plurality of nozzles 711 are arranged along a direction parallel to the width direction X of the image forming drum 50 and perpendicular to the transport direction F. The recording head 71 selectively ejects ink from the plurality of nozzles 711 to form an image on the recording medium P held on the image forming drum 50. That is, the recording head 71 is provided such that the plurality of nozzles 711 are exposed on the lower surface side of the head unit 70. The recording head 71 shown in FIG. 3B has a plurality of nozzles 711 arranged in two rows of nozzles along the X direction.

The plurality of recording heads 71 are arranged in a row along the X direction, for example, as shown in FIG. 3B. The recording head 71 is supported by a support plate 71a. The plurality of recording heads 71 are arranged so that the positional relationship between the adjacent recording heads 71 is staggered in a direction orthogonal to the X direction (conveying direction F). Here, two or more recording heads 71 may be provided continuously along the recording medium conveyance direction F to form a set of recording heads.

In the ink path from the ink tank 72 to each recording head 71, a supply pressure adjusting mechanism is provided, and the supply pressure is slightly lower than the atmospheric pressure so that ink does not spill out from the nozzle 711 of each recording head 71. Has been adjusted.
The ink heater 73 includes a temperature sensor that detects the temperature of the supplied ink, and is output-controlled so as to be an appropriate temperature while monitoring the supplied ink temperature.

Further, as described above, the head unit 70 is provided along the image forming drum 50 side by side for each color (MCKY) used for image formation. In the inkjet recording apparatus 1 shown in FIG. 1, each color is arranged in the order of M, C, K, and Y from the upstream along the conveyance direction F of the recording medium P that is conveyed along with the rotation of the image forming drum 50. A corresponding head unit 70 is provided.
As shown in FIG. 4, the width of the head unit 70 in the X direction is wider than the width of the recording medium P held and conveyed by the image forming drum 50 in the X direction (for example, the width of the image forming drum 50). The width of the head unit 70 is set to be smaller, but the width of the head unit 70 is fixed. Image formation is performed by ejecting ink so as to be equal to or greater than the maximum width of the region. That is, the inkjet recording apparatus 1 is a one-pass inkjet recording apparatus, and the head unit 70 records a plurality of nozzles 711 by a plurality of recording heads 71 arranged side by side in the X direction when an image is formed. The direction (X direction) perpendicular to the direction in which the head 71 and the recording medium P move relatively is provided to be equal to or greater than the maximum width of an image formed on the recording medium P.
In this embodiment, a plurality of recording heads 71 are arranged in the X direction orthogonal to the recording medium conveyance direction so as to be equal to or larger than the maximum width of the image. It may be configured to be equal to or greater than the maximum width.

Each recording head 71 is provided with an actuator (not shown) for discharging the ink by increasing the pressure in each nozzle 711. By ejecting ink from any one of the nozzles 711, Image formation can be performed.

Further, in the present embodiment, a mist collection unit 76 described later is provided in the vicinity of the recording head 71.

[Image forming part: Cleaning part]
The four head units 70 are supported in the image forming unit 20 so as to be individually movable along the X direction. Specifically, as shown in FIG. 4, the head unit 70 is provided so as to be movable between the image forming drum 50 and the cleaning unit 60 arranged in the X direction. The head unit 70 moves to a position where the lower surface faces the image forming drum 50 during image formation, and moves to a position where the lower surface faces the cleaning unit 60 during various types of maintenance.
The cleaning unit 60 includes a waste ink unit (not shown) that receives and aggregates ink ejected from the head unit 70 during maintenance, and the ink ejected from the head unit 70 during maintenance maintains the inside of the image forming unit 20. To prevent fouling.

[Image forming part: Irradiation part]
The irradiation unit 93 includes, for example, a fluorescent tube such as a low-pressure mercury lamp, and irradiates energy rays such as ultraviolet rays by light emitted from the fluorescent tube. The irradiation unit 93 is provided in the vicinity of the outer peripheral surface of the image forming drum 50 and on the downstream side of each head unit 70 in the conveyance direction F of the recording medium P due to the rotation of the image forming drum 50. The irradiating unit 93 irradiates the recording medium P held by the image forming drum 50 and ejects the ink with an energy ray, and cures the ink on the recording medium P by the action of the energy ray.
The fluorescent tube emitting ultraviolet light is not limited to a low-pressure mercury lamp, but a mercury lamp having an operating pressure of several hundred [Pa] to 1 mega [Pa], a light source usable as a sterilizing lamp, a cold cathode tube, and an ultraviolet laser light source. A metal halide lamp, a light emitting diode, and the like can be given, and it is desirable that the light source is a light-saving light source (for example, a light emitting diode) that can irradiate ultraviolet rays with higher illuminance. The energy rays are not limited to ultraviolet rays, but may be any energy rays having a property of curing ink according to the properties of the ink, and the light source is also replaced according to the energy rays.

[Image forming unit: transport mechanism]
The transport mechanism 96 includes a paper discharge drum 961 that receives the recording medium P from the image forming drum 50, two

sprockets

963 and 964, and a timing belt 965 that is stretched therebetween.
The timing belt 965 is provided between the paper discharge drum 961 and the paper discharge unit 30 and conveys the recording medium P.

Similarly to the image forming drum 50, the paper discharge drum 961 includes one claw portion 962 that sandwiches one end portion of the recording medium P. The claw portion 962 of the paper discharge drum 961 extends from the image forming drum 50 to the paper discharge drum 961. And a plurality of claws constituting the claw portion 962 are opened when the paper discharge position and the delivery drum 961 to the timing belt 965 are located (the position where the claw portion 962 is closest to the timing belt 965). A cam mechanism for receiving or delivering the recording medium P is built in the paper discharge drum 961.

[Image forming unit: second heater]
The second heater 94 is a lamp heater made of, for example, a non-contact type halogen lamp that irradiates infrared rays. The second heater 94 has a reflector similarly to the first heater 91, and efficiently covers the outer peripheral surface of the image forming drum 50. Irradiate and heat.
Since the second heater 94 is provided from the paper discharge position to the supply position in the transport direction F, the recording medium P may exist on the outer peripheral surface of the image forming drum 50. The outer peripheral surface of the image forming drum 50 can be directly heated in a non-existing region.
A temperature sensor 95 is provided in the vicinity of the second heater 94 and on the downstream side in the transport direction. The temperature sensor 95 may be a contact-type temperature detection element such as a thermocouple or a thermistor, but a non-contact type temperature detection element such as a thermopile is more preferable.
The second heater 94 is controlled based on the temperature detected by the temperature sensor 95 so that the outer peripheral surface of the image forming drum 50 that has passed near the second heater 94 has a predetermined temperature.

[Output section]
The paper discharge unit 30 includes a plate-shaped paper discharge tray 31 on which the recording medium P sent out from the image forming unit 20 by the transport mechanism 96 is placed, and the recording medium P after image formation is taken out by the user. Store up to.

[ink]
The ink used in the present embodiment is an actinic ray curable ink that cures when irradiated with energy rays (active rays). Further, this ink has a property of changing phase between gel or solid and liquid depending on the temperature of the ink.
This actinic ray curable ink contains, for example, 1% by mass or more and less than 10% by mass of a gelling agent, and is characterized by reversibly sol-gel phase transition depending on temperature. The sol-gel phase transition is a solution state with fluidity at high temperatures, but when cooled below the gelation temperature, the entire liquid gels and changes to a state in which it loses fluidity, and conversely loses fluidity at low temperatures. This refers to a phenomenon that returns to a fluid state with fluidity when heated to a temperature equal to or higher than the solation temperature.

Next, the configuration of the recording head 71 according to the present embodiment will be described.
As shown in FIG. 5, a first guide portion 74 is fixed to the upstream front edge portion in the conveyance direction F of the recording medium P of the recording head 71 (that is, the rotation direction of the image forming drum 50). . The first guide portion 74 extends along the nozzle arrangement direction of the recording head 71. The distance between the lower surface of the first guide portion 74 and the outer peripheral surface of the image forming drum 50 gradually decreases from the upstream side to the downstream side in the conveyance direction F of the recording medium P, and a plurality of nozzles 711 are formed on the most downstream side. A guide surface 74a that coincides with the nozzle surface 71f is formed. More specifically, the guide surface 74a has a so-called bullet shape in a sectional view, and as shown in FIG. 6, the guide surface 74a is closer to the outer peripheral surface of the image forming drum 50, that is, the conveyance direction F of the recording medium P. From the upstream side to the downstream side, the angle formed by the tangent line of the guide surface 74a and the tangent line of the outer peripheral surface of the image forming drum 50 is reduced. In particular, at the position closest to the recording head 71 on the guide surface 74a, the guide surface 74a and the outer peripheral surface of the image forming drum 50 are closest, and the tangent line of the guide surface 74a and the tangent line of the outer peripheral surface of the image forming drum 50 at this position. The first guide portion 74 is formed so as to be substantially parallel to the.

Further, a second guide portion 75 is fixed to the rear edge portion of the recording head 71 on the downstream side in the conveyance direction F of the recording medium P. The second guide portion 75 extends along the nozzle arrangement direction of the recording head 71. The distance between the lower surface of the second guide portion 75 and the outer peripheral surface of the image forming drum 50 gradually increases from the upstream side to the downstream side in the conveyance direction F of the recording medium P, and coincides with the nozzle surface 71f on the most upstream side. Such a guide surface 75a is formed. More specifically, the guide surface 75a has a so-called bullet shape in a cross-sectional view, and the farther from the outer peripheral surface of the image forming drum 50, that is, from the upstream side to the downstream side in the conveyance direction F of the recording medium P. Thus, the angle formed by the tangent line of the guide surface 75a and the tangent line of the outer peripheral surface of the image forming drum 50 is increased.

Further, a mist collecting unit 76 as a collecting unit is provided downstream of the recording head 71 in the conveyance direction F of the recording medium P. The mist collection unit 76 is attached to the support plate 71 a and is provided so as to penetrate the lower surface of the cover body of the head unit 70. For example, the lower part of the mist collecting unit 76 is formed in a rectangular parallelepiped, the longitudinal direction thereof extends along the nozzle arrangement direction of the recording head 71, and an introduction port 76a for introducing gas is formed on the bottom surface. . The introduction port 76a is disposed so as to be continuous with the distal end of the guide surface 75a of the second guide portion 75, and faces the direction along the curved surface of the guide surface 75a. The upper part of the mist collecting unit 76 forms a cylindrical body, and the cylindrical body extends upward from the center of the lower part formed in a rectangular parallelepiped, and a discharge port 76b is opened at the upper end. Yes. The discharge port 76b may be provided at any position, but as described later, the discharge port 76b is provided at a position where the surrounding members are less likely to be soiled by satellites or ink mist mixed in the gas discharged from the discharge port 76b. It is preferred that Further, the discharge port 76b may be connected to a drain tank that stores the drain ink.

A filter 76 c is provided inside the mist collection unit 76. The filter 76c is made of, for example, a non-woven fabric or the like, and is disposed so as to close the inside of the cylindrical body portion described above.

An intake fan 76d as an intake section is provided above the filter 76c of the mist collecting section 76, that is, downstream of the filter 76c in the flow direction of the gas introduced from the introduction port 76a. For example, the intake fan 76d is electrically connected to a control unit (not shown), and is driven to rotate in response to an input of a drive signal from the control unit. The intake fan 76d sucks the gas introduced from the introduction port 76a and exhausts the sucked gas. Delivered to outlet 76b. The intake means is not limited to the intake fan 76d, and any means can be employed as long as it can intake the gas introduced from the introduction port 76a.

Since the present embodiment is configured as described above, when the image forming drum 50 rotates as shown in FIG. 5, it flows down along the transport direction F of the recording medium P to the surface of the image forming drum 50. An air flow is generated. At this time, an air flow having a higher flow velocity is generated as it approaches the outer peripheral surface of the image forming drum 50.

Of the air flow generated in this way, an air flow having a large flow velocity near the outer peripheral surface of the image forming drum 50 directly enters the gap between the nozzle surface 71 f of the recording head 71 and the outer peripheral surface of the image forming drum 50. On the other hand, the air flow toward the front edge portion of the recording head 71 at a position slightly away from the outer peripheral surface of the image forming drum 50 collides with the guide surface 74 a of the first guide portion 74. The airflow that has collided with the guide surface 74a (that is, the front edge portion of the recording head 71) moves along the curved surface of the guide surface 74a and is guided to the introduction point A, and near the outer peripheral surface of the image forming drum 50 described above. Then, the air flows into the gap between the nozzle surface 71 f of the recording head 71 and the outer peripheral surface of the image forming drum 50. Since the guide surface 74a has the shape described above, the flow direction of the air flow guided by the guide surface 74a and reaching the introduction point A is substantially the direction along the transport direction F of the recording medium P. It is possible to suppress the occurrence of a turbulent flow region due to the crossing of the air flow in the gap between the nozzle surface 71 f of 71 and the outer peripheral surface of the image forming drum 50.

The air flow in the gap between the nozzle surface 71f and the outer peripheral surface of the image forming drum 50 includes the air flow guided by the guide surface 74a. Therefore, the air flow is compressed and the air pressure becomes high. The flow velocity is larger than A. The speed of the air flow thus increased can be discharged from the nozzle 711 together with the main droplet, although the influence on the main droplet which is an ink droplet for landing on the recording medium P discharged from the nozzle 711 is small. The effect on small ink droplets such as certain satellites and ink mists is large. For this reason, such ink droplets having a small particle diameter are blown downstream by the accelerated air flow. In the present embodiment, the guide surface 74a of the first guide portion 74 suppresses the generation of a turbulent flow region in the gap between the nozzle surface 71f of the recording head 71 and the outer peripheral surface of the image forming drum 50, and the air flow can be stabilized. In addition, since the flow velocity of the air flow in the gap between the nozzle surface 71f and the outer peripheral surface of the image forming drum 50 can be increased, satellites and ink mist can be effectively blown by the air flow. Ink mist adheres to the nozzle surface 71f and discharge failure occurs, and deterioration of image quality due to satellite or ink mist adhesion to the recording medium P can be suppressed.

Thereafter, the air flow derived from the gap between the nozzle surface 71f and the outer peripheral surface of the image forming drum 50 has a reduced atmospheric pressure at the derived point C. Flows down along the conveyance direction F of the recording medium P, but the air flow at a position away from the outer peripheral surface of the image forming drum 50 diffuses in a direction different from the conveyance direction F. In the present embodiment, since the guide surface 75a of the second guide portion 75 is formed as described above, the atmospheric pressure at the derivation point C can be gradually reduced, and in a direction different from the conveyance direction F of the recording medium P. The diffused air flow is guided along a surface shape of the guide surface 75a in a predetermined direction away from the outer peripheral surface of the image forming drum 50, and Karman vortex can be prevented from being generated on the wall surface side of the recording head 71.

The air flow guided to the guide surface 75a of the second guide portion 75 flows down toward the introduction port 76a of the mist collecting portion 76. Thereby, the air flow guided by the second guide portion 75 can be introduced into the mist collecting portion 76 without leakage. The air flow introduced into the mist collecting unit 76 from the introduction port 76a is sucked by the intake fan 76d and passes through the filter 76c. Since the filter 76c adsorbs ink components such as satellites and ink mist contained in the air flow and allows only gas to pass therethrough, the satellite and ink mist mixed in the air flow can be reliably collected. Further, by sucking the air flow with the intake fan 76d, more air flow mixed with satellites and ink mists can be taken in and efficiently collected. Further, since the intake fan 76d is provided downstream of the filter 76c in the air flow direction, the intake fan 76d can be prevented from being contaminated.

The air flow from which satellites and ink mist have been removed by the filter 76c is discharged from the discharge port 76b. Therefore, it is possible to reduce the contamination of the recording head 71 and its peripheral members with ink.

In the present embodiment, the first guide portion 74 and the second guide portion 75 are provided integrally with the recording head 71, but the first guide portion 74 and the second guide portion 75 are different from the recording head 71. The structure provided in another body may be sufficient.

In the present embodiment, the mist collection unit 76 is provided in the head unit 70. However, the mist collection unit 76 may be provided separately from the head unit 70.

Next, another embodiment of the present invention will be described with reference to FIGS.
The embodiment shown in FIG. 7 is a recording medium of four head units 70 arranged in parallel so that the nozzle surface faces the outer peripheral surface of the image forming drum 50 along the conveyance direction F of the recording medium P. The first guide portion 74 described above is provided at the front edge portion of the magenta (M) head unit 70 disposed on the most upstream side in the P transport direction F, and the yellow (Y) head disposed on the most downstream side. The second guide portion 75 and the mist collection portion 76 described above are provided at the rear edge portion of the unit 70. Since the embodiment shown in FIG. 7 is configured as described above, when the image forming drum 50 rotates, an air flow that flows down along the conveyance direction F of the recording medium P is generated on the surface of the image forming drum 50. . Then, the air flow toward the front edge portion of the head unit 70 collides with the first guide portion 74 and is guided by the guide surface of the first guide portion 74, and the lower surface of each head unit 70 and the outer peripheral surface of the image forming drum 50. Down the gap. Thereafter, the air flow derived from the gap between the lower surface of each head unit 70 and the outer peripheral surface of the image forming drum 50 is guided by the guide surface of the second guide portion 75 and introduced into the mist collecting portion 76. Here, the four head units 70 are arranged at a predetermined interval, and a turbulent flow region is generated when an air flow enters the gap between the head units 70. A plate-like lid member 77 is provided to prevent the air flow from entering.

Furthermore, as shown in FIG. 8, each head unit 70 includes two recording heads 71 </ b> A and 71 </ b> B arranged in parallel along the conveyance direction F of the recording medium P, and the recording heads 71 </ b> A and 71 </ b> B are head units. 70 is provided so as to protrude downward from the lower surface of the cover body 70 (that is, the surface facing the image forming drum 50), the air flow changes in the direction of the air flow at the side walls and corners of the recording heads 71A and 71B. And a turbulent region may occur. Therefore, the flow direction of the air flow that enters the gap between the head unit 70 and the outer peripheral surface of the image forming drum 50 and flows in the vicinity of the front edge portion of the recording head 71A and the rear edge portion of the recording head 71B is guided. It is preferable to provide bullet-shaped

guide members

78a and 78b for suppressing the occurrence at the front edge portion of the recording head 71A and the rear edge portion of the recording head 71B, respectively. The

guide members

78a and 78b may be integrally attached to the recording heads 71A and 71B or may be configured separately.

Further, as shown in FIG. 8, since the recording heads 71A and 71B are provided at a predetermined interval, a turbulent flow region may be generated when an air flow enters the gap between the recording heads 71A and 71B. It is more preferable to provide a closing member 79 for closing the gap between the recording heads 71A and 71B to prevent the air flow from entering.

Thus, according to the configuration as described above, the head unit 70 and the head unit 70 disposed on the most downstream side in the transport direction F of the recording medium P to the head unit 70 disposed on the most downstream side In the gap with the outer peripheral surface of the image forming drum 50, an air flow having a high flow velocity can be caused to flow down while suppressing the occurrence of a turbulent flow area, and satellites and ink mist generated as ink droplets are ejected by the head units 70. Can be recovered without adhering to the recording heads 71A and 71B and surrounding members and fouling them. Further, it is possible to suppress adhesion to the recording medium P, and it is possible to reduce deterioration of image quality.

As described above, according to the present embodiment, the image forming drum 50 is conveyed by holding the recording medium P on the outer peripheral surface and rotating. The recording head 71 is provided at a position away from the outer peripheral surface of the image forming drum 50 by a predetermined distance, and a nozzle surface on which a plurality of nozzles 711 that eject ink are arranged along a direction intersecting the rotation direction of the image forming drum 50. 71f. The first guide portion 74 guides the air flow toward the upstream front edge portion of the recording head 71 in the rotational direction of the image forming drum 50 in the direction along the rotational direction of the image forming drum 50 and forms the image with the recording head 71. A guide surface 74 a is introduced into the gap with the drum 50. The second guide portion 75 has a guide surface 75 a that guides the air flow derived from the gap between the recording head 71 and the image forming drum 50 in a direction away from the outer peripheral surface of the image forming drum 50. The mist collection unit 76 has an introduction port 76a for introducing the air flow guided by the second guide unit 75, and collects ink components contained in the air flow introduced into the introduction port 76a. As a result, the airflow in the gap between the recording medium transported by the image forming drum and the recording head is stabilized to prevent unnecessary ink from adhering to the recording medium and the nozzle surface, and satellites and ink mist derived from the gap are also prevented. By collecting the unnecessary ink component by suppressing the diffusion of the air flow containing the unnecessary ink component, it is possible to prevent the recording head and surrounding members from being contaminated, and to prevent the unnecessary ink component from adhering to the recording medium. It is possible to prevent the deterioration of the image quality. Further, according to the present embodiment, unnecessary ink components can be efficiently removed using the airflow generated by the rotation of the image forming drum, so that a special device or the like for generating the airflow is not required. The increase in cost can be suppressed.

Further, according to the present embodiment, the first guide portion 74 has the guide surface 74a so that the distance from the outer peripheral surface of the image forming drum 50 gradually decreases from the upstream side to the downstream side in the rotation direction of the image forming drum 50. Is formed. As a result, it becomes possible to guide the flow direction of the airflow colliding with the guide portion with a simple configuration so as to approach the rotation direction of the image forming drum.

Further, according to the present embodiment, the closer the first guide portion 74 is to the outer peripheral surface of the image forming drum 50, the smaller the angle formed by the tangent line of the guide surface 74 a and the tangent line of the outer peripheral surface of the image forming drum 50. Thus, the guide surface 74a has a shell shape. As a result, it is possible to guide the airflow colliding with the guide portion so as to be closer to the rotation direction of the image forming drum.

Further, according to the present embodiment, the second guide portion 75 has the guide surface 75a so that the distance from the outer peripheral surface of the image forming drum 50 gradually increases from the upstream side to the downstream side in the rotation direction of the image forming drum 50. Is formed. As a result, the air flow derived from the gap between the recording head and the image forming drum can be stabilized and efficiently guided with a simple configuration.

Further, according to the present embodiment, the second guide portion 75 has a larger angle formed by the tangent line of the guide surface 75 a and the tangent line of the outer peripheral surface of the image forming drum 50 as it is farther from the outer peripheral surface of the image forming drum 50. Thus, the guide surface 75a has a shell shape. As a result, the airflow derived from the gap between the recording head and the image forming drum can be guided more efficiently.

Further, according to the present embodiment, the mist collecting section 76 is provided such that the introduction port 76a is continuously arranged on the guide surface 75a of the second guide section 75. As a result, the airflow guided by the second guide part can be more reliably taken into the recovery part.

Further, according to the present embodiment, the mist collecting unit 76 includes the discharge port 76b for discharging the air flow introduced from the introduction port 76a to a predetermined position. As a result, it is possible to improve the flowability of the airflow in the recovery unit. Further, it is possible to avoid contamination of peripheral members due to unnecessary ink components contained in the airflow.

In addition, according to the present embodiment, since the introduction port 76a faces the direction along the guide surface 75a of the second guide part 75, the airflow guided by the second guide part is more reliably collected. Will be able to capture.

Further, according to the present embodiment, the mist collecting unit 76 has the filter 76c through which the air flow introduced from the introduction port 76a passes, and the ink component contained in the air flow introduced into the introduction port by the filter 76c. It is recovered by adsorbing. As a result, unnecessary ink components contained in the airflow can be more reliably collected, and contamination of surrounding members can be avoided.

Further, according to the present embodiment, the mist collecting section 76 has the intake fan 76d for sucking the airflow introduced from the introduction port 76a. As a result, more air currents containing unnecessary ink components can be taken in, and unnecessary ink components can be recovered efficiently.

Further, according to the present embodiment, the mist collecting section 76 has the intake fan 76d disposed downstream of the filter 76c in the flow direction of the air flow introduced from the introduction port 76a, thereby preventing the intake section from being contaminated. can do.

Further, according to the present embodiment, the image forming drum 50 is conveyed by holding the recording medium P on the outer peripheral surface and rotating. The plurality of head units 70 includes a recording head 71 in which a plurality of nozzles for ejecting ink are arranged along a direction intersecting the rotation direction of the image forming drum 50, and a predetermined distance from the seed surface of the image forming drum 50. They are arranged in parallel along the rotation direction of the image forming drum 50 at distant positions. The first guide portion 74 causes the air flow colliding with the front edge portion of the head unit 70 provided on the most upstream side in the rotation direction of the image forming drum 50 among the plurality of head units 70 to rotate the image forming drum 50. The guide surface 74a is introduced in the gap between the head unit 70 and the image forming drum 50. The second guide unit 75 forms an image of the air flow derived from the gap between the head unit 70 provided on the most downstream side in the rotation direction of the image forming drum 50 and the image forming drum 50 among the plurality of head units 70. It has a guide surface 75 a that guides in a direction away from the outer peripheral surface of the drum 50. The mist collection unit 76 has an introduction port 76a for introducing the air flow guided by the second guide unit 75, and collects ink components contained in the air flow introduced into the introduction port 76a. As a result, the air flow in the gap between the recording medium conveyed by the image forming drum and the head unit is stabilized to prevent unnecessary ink from adhering to the recording medium and the nozzle surface, and satellites and ink mist derived from the gap are also prevented. It is possible to prevent the head unit and its surrounding members from being contaminated by suppressing the diffusion of air currents containing unnecessary ink components and collecting unnecessary ink components, and to prevent unnecessary ink components from adhering to the recording medium. It is possible to prevent the deterioration of the image quality. Further, according to the present embodiment, unnecessary ink components can be efficiently removed using the airflow generated by the rotation of the image forming drum, so that a special device or the like for generating the airflow is not required. The increase in cost can be suppressed.

Further, according to the present embodiment, the plurality of head units 70 are arranged at a predetermined interval from each other. The lid member 77 closes the gaps between the plurality of head units 70. As a result, it is possible to prevent an air current from entering the gap between the head units and thereby generating a turbulent flow area in the gap between the head unit and the image forming drum.

Further, according to the present embodiment, the recording heads 71A and 71B are provided so as to protrude from the surface of the head unit 70 facing the image forming drum 50. The

guide members

78a and 78b guide the air flow that enters the gap between the head unit 70 and the outer peripheral surface of the image forming drum 50 and flows down near the front and rear edges of the recording heads 71A and 71B. As a result, it is possible to prevent a turbulent flow region from being generated due to a change in the flow direction of the airflow at the side walls and corners of the recording head provided protruding from the head unit.

Further, according to the present embodiment, the head unit 70 includes a plurality of recording heads 71A and 71B arranged in parallel from the upstream side to the downstream side in the rotation direction of the image forming drum 50. The closing member 79 closes the gap between the plurality of recording heads 71A and 71B arranged in parallel. As a result, it is possible to prevent a turbulent flow region from being generated due to an air current entering the gaps between the plurality of recording heads and a change in the flow direction of the air current.

The description in the embodiment of the present invention is an example of the ink jet recording apparatus according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of each functional unit constituting the ink jet recording apparatus can be appropriately changed.

In the present embodiment, the shape of the guide surface 74a of the first guide portion 74 is a cannonball shape, but the shape of the guide surface 74a is not limited to this, and the airflow toward the front edge of the recording head 71 is imaged. The shape may be any shape as long as it can be guided in a direction along the rotation direction R of the forming drum 50 and introduced into the gap between the recording head 71 and the image forming drum 50, for example, a guide surface 74a may be a tapered shape having no curved surface.

In the present embodiment, the shape of the guide surface 75a of the second guide portion 75 is a bullet shape, but the shape of the guide surface 75a is not limited to this, and from the gap between the recording head 71 and the image forming drum 50. Any shape can be used as long as the derived airflow can be guided in a direction away from the outer peripheral surface of the image forming drum 50. For example, the guide surface 75a has a tapered shape without a curved surface. May be.

In the present embodiment, the first guide portion 74 and the second guide portion 75 are fixedly provided on the recording head 71. However, the front edge portion and the rear edge portion of the recording head 71 are notched. Thus, the first guide portion and the second guide portion may be formed.

In the present embodiment, the intake fan 76d is provided in the mist collecting section 76 so as to effectively take in the air flow including satellites and ink mist. However, the intake fan 76d may not be provided.

In the present embodiment, the filter 76c is provided in the mist collecting unit 76 so as to effectively collect satellites and ink mist contained in the air flow. However, the filter 76c may not be provided.

In the present embodiment, the intake fan 76d is provided on the downstream side of the filter 76c in the flow-down direction of the airflow introduced from the introduction port 76a of the mist collecting section 76, but the intake air is provided on the upstream side of the filter 76c. A fan 76d may be provided.

Further, in the present embodiment, the direction of the introduction port 76a of the mist collecting unit 76 is directed in the direction along the curved surface of the guide surface 75a of the second guide unit 75, but is guided by the second guide unit 75. Any direction may be used as long as the airflow can be taken in.

Further, in the present embodiment, the introduction port 76a of the mist collection unit 76 is arranged so as to be continuous with the guide surface 75a of the second guide unit 75, but the introduction port 76a and the guide surface 75a are separated from each other. May be.

As described above, the present invention stabilizes the air flow in the gap between the recording medium conveyed by the image forming drum and the recording head to prevent unnecessary ink from adhering to the recording medium and the nozzle surface, and from the gap. The present invention is suitable for providing an ink jet recording apparatus capable of preventing the recording head and surrounding members from being stained by suppressing the diffusion of the derived air flow containing unnecessary ink.

DESCRIPTION OF SYMBOLS 1 Inkjet recording apparatus 50 Image forming drum 70

Head unit

71, 71A, 71B Recording head 71f Nozzle surface 711 Nozzle 74 1st guide part (1st guide part)
74a Guide surface 75 2nd guide part (2nd guide part)
75b Guide surface 76 Mist collection section (collection section)

76a Inlet port

76b Outlet port 76c Filter 76d Intake fan (intake unit)
77

Lid members

78a, 78b Guide member 79 Closure member

Claims

An inkjet recording apparatus that records on a recording medium by discharging ink,
An image forming drum that conveys the recording medium by holding and rotating the recording medium on an outer peripheral surface;
A recording head provided at a position away from the outer peripheral surface of the image forming drum by a predetermined distance and having a nozzle surface in which a plurality of nozzles for ejecting ink are arranged along a direction intersecting the rotation direction of the image forming drum;
The air flow toward the upstream front edge of the recording head in the rotation direction of the image forming drum is guided in the direction along the rotation direction of the image forming drum and introduced into the gap between the recording head and the image forming drum. A first guide portion having a guide surface;
A second guide portion having a guide surface for guiding an air flow derived from a gap between the recording head and the image forming drum in a direction away from the outer peripheral surface of the image forming drum;
A recovery portion that has an inlet for introducing an airflow guided by the second guide portion, and that recovers an ink component contained in the airflow introduced into the inlet;
An ink jet recording apparatus comprising:
An inkjet recording apparatus that records on a recording medium by discharging ink,
An image forming drum that conveys the recording medium by holding and rotating the recording medium on an outer peripheral surface;
A plurality of nozzles for ejecting ink has a recording head arranged along a direction intersecting the rotation direction of the image forming drum, and the nozzle of the image forming drum is located at a predetermined distance from the outer peripheral surface of the image forming drum. A plurality of head units arranged in parallel along the rotation direction;
The head unit is configured to guide an air flow toward a front edge portion of a head unit provided on the most upstream side in the rotation direction of the image forming drum among the plurality of head units in a direction along the rotation direction of the image forming drum. And a first guide portion having a guide surface to be introduced into a gap between the image forming drum and the image forming drum,
Among the plurality of head units, an air flow derived from a gap between the head unit provided on the most downstream side in the rotation direction of the image forming drum and the image forming drum is away from the outer peripheral surface of the image forming drum. A second guide part having a guide surface for guiding;
A recovery portion that has an inlet for introducing an airflow guided by the second guide portion, and that recovers an ink component contained in the airflow introduced into the inlet;
An ink jet recording apparatus comprising:
The plurality of head units are arranged at predetermined intervals from each other,
The inkjet recording apparatus according to claim 2, further comprising a lid member that closes a gap between the plurality of head units.
The recording head is provided so as to protrude from a surface of the head unit facing the image forming drum,
3. A guide member that guides an airflow that enters a gap between the head unit and the outer peripheral surface of the image forming drum and flows near the front edge and the rear edge of the recording head. 4. An ink jet recording apparatus according to item 3.
The head unit includes a plurality of the recording heads arranged in parallel from the upstream side to the downstream side in the rotation direction of the image forming drum,
The inkjet recording apparatus according to any one of claims 2 to 4, further comprising a closing member that closes a gap between the plurality of recording heads arranged side by side.
The first guide portion is characterized in that the guide surface is formed such that the distance from the outer peripheral surface of the image forming drum gradually decreases from the upstream side to the downstream side in the rotation direction of the image forming drum. The inkjet recording apparatus according to any one of claims 1 to 5.
In the first guide portion, the guide surface has a bullet shape so that an angle formed by a tangent line of the guide surface and a tangent line of the outer peripheral surface of the image forming drum decreases as the distance from the outer peripheral surface of the image forming drum increases. The ink jet recording apparatus according to claim 6, wherein the ink jet recording apparatus is provided. *
The second guide portion has the guide surface formed such that the distance from the outer peripheral surface of the image forming drum gradually increases from the upstream side to the downstream side in the rotation direction of the image forming drum. The ink jet recording apparatus according to any one of claims 1 to 7.
The guide surface of the second guide portion is bullet-shaped so that an angle formed by a tangent line of the guide surface and a tangent line of the outer peripheral surface of the image forming drum increases as the distance from the outer peripheral surface of the image forming drum increases. The inkjet recording apparatus according to claim 8, wherein:
The inkjet according to any one of claims 1 to 9, wherein the recovery unit is provided such that the introduction port is continuously disposed on a guide surface of the second guide unit. Recording device.
The inkjet recording apparatus according to any one of claims 1 to 10, wherein the recovery unit includes a discharge port for discharging the airflow introduced from the introduction port to a predetermined position.
The inkjet recording apparatus according to any one of claims 1 to 11, wherein the introduction port faces a direction along a guide surface of the second guide portion.
The recovery unit includes a filter through which an air flow introduced from the introduction port passes, and recovers the filter by adsorbing an ink component contained in the air flow introduced into the introduction port by the filter. Item 13. The ink jet recording apparatus according to any one of Items 1 to 12.
The inkjet recording apparatus according to any one of claims 1 to 13, wherein the recovery unit includes an intake unit for sucking an airflow introduced from the introduction port.
The recovery part has an intake part for taking in the airflow introduced from the introduction port, and the intake part is arranged downstream of the filter in the flow-down direction of the airflow introduced from the introduction port. The inkjet recording apparatus according to claim 13.