JP7622372B2 - LIQUID EJECTOR AND MIST COLLECTION PART - Google Patents

Description

The present invention relates to a liquid ejection device and a mist collection unit.

The inkjet recording device of Patent Document 1 is known as an example of a conventional liquid ejection device. This inkjet recording device has a recording head and a mist collection section that collects the mist of ink emitted from the recording head, and the mist collection section has a duct. The duct extends upward from a suction port at the bottom and bends horizontally at the top, and a fan and filter are located inside this horizontal part of the duct.

JP 2005-271314 A

In the inkjet recording of Patent Document 1, air containing mist is sucked into a duct from a suction port by a fan, flows upward through the duct, turns horizontally, and passes through a filter where the mist is collected. When this air turns horizontally from above, a convection current is generated that flows in the opposite direction to the direction of the turn. This convection current causes the mist to flow toward the inner wall of the duct opposite the filter and adhere to the inner wall. This causes the adhered mist to coagulate, and the ink may flow down along the inner wall, soiling the recording medium, etc.

In view of this situation, the present invention aims to provide a liquid ejection device and a mist collection section that can reduce the amount of liquid that flows down from the mist collection section.

A liquid ejection device according to one aspect of the present invention comprises a head which ejects liquid onto an ejected medium, and a mist collection section for collecting a mist of the liquid, the mist collection section having an air flow path through which air flows, and a filter arranged within the air flow path and having a filter surface, the air flow path having an intake port for drawing in the air, an exhaust port for exhausting the air, a corner portion provided between the intake port and the exhaust port, a first portion extending from the intake port to the corner portion in a first direction, and a second portion extending from the corner portion to the exhaust port in a second direction intersecting the first direction, the corner portion having an opposing surface intersecting the second direction, the filter surface opposing the opposing surface, and having a first end closer to the intake port in the first direction and a second end farther from the intake port, the second end being closer to the opposing surface in the second direction than the first end.
A mist collection section according to one aspect of the present invention comprises an air flow path for flowing air, and a filter disposed within the air flow path and having a filter surface, the air flow path having an intake port for drawing in the air, an exhaust port for exhausting the air, a corner portion provided between the intake port and the exhaust port, a first portion extending from the intake port to the corner portion in a first direction, and a second portion extending from the corner portion to the exhaust port in a second direction intersecting the first direction, the corner portion having an opposing surface intersecting the second direction, the filter surface facing the opposing surface and having a first end closer to the intake port in the first direction and a second end farther from the intake port, the second end being closer to the opposing surface in the second direction than the first end.

The present invention has the effect of providing a liquid ejection device and a mist collection section that can reduce the amount of liquid that flows down from the mist collection section.

The above objects, other objects, features, and advantages of the present invention will become apparent from the following detailed description of preferred embodiments, taken in conjunction with the accompanying drawings.

1 is a perspective view of a liquid ejection device according to an embodiment of the present invention. FIG. 2 is a functional block diagram showing a configuration of the liquid ejection device of FIG. 1 . 2 is a schematic diagram of the head unit of FIG. 1 as viewed from below. FIG. FIG. 2 is a cross-sectional view that illustrates the liquid ejection device of FIG. 1 . 5 is a cross-sectional view of the mist collecting portion of FIG. 4 taken along a cross section perpendicular to the front-rear direction. 6 is a schematic diagram of the mist collecting unit of FIG. 5 as viewed from the left side. FIG. 11 is a cross-sectional view of a mist collecting portion of a liquid ejecting device according to a modified example of an embodiment of the present invention, taken along a cross section perpendicular to the front-rear direction.

The following describes in detail an embodiment of the present invention with reference to the drawings. Note that, in the following, the same or corresponding elements are given the same reference symbols throughout the drawings, and redundant explanations will be omitted.

<Configuration of Liquid Ejection Apparatus>
As shown in Fig. 1, a liquid ejection device 10 according to an embodiment of the present invention is, for example, an inkjet printer that ejects liquid such as ink from a head 20 onto an ejection receiving medium A (Fig. 4) to print an image. Examples of A include sheets such as fabric and paper, and three-dimensional objects such as balls and mugs. The liquid ejection device 10 includes a housing 11, a head unit 12, a scanning device 50, a transport device 60, and a control device 70 (Fig. 2). Details of the control device 70 will be described later.

The scanning direction in which the head 20 is moved by the scanning device 50 is referred to as the left-right direction, and the transport direction in which the ejection medium A is transported by the transport device 60 is referred to as the front-rear direction. The ejection direction perpendicular to the ejection surface 20a (Figure 4) of the head 20 is referred to as the up-down direction. The scanning direction, transport direction, and ejection direction intersect with each other (for example, are perpendicular). However, the arrangement of the liquid ejection device 10 is not limited to this.

The housing 11 houses the head unit 12, the scanning device 50, the transport device 60, and the control device 70. The housing 11 has a main body with an opening at the top, and a lid that can be opened and closed to cover the top opening of the main body.

The main body has a front wall and a rear wall. The rear wall is provided behind and parallel to the front wall. A front opening 11a opens into the front wall, and a rear opening 11b opens into the rear wall. When viewed from the front, the front opening 11a and the rear opening 11b are arranged so as to overlap each other. The internal space of the main body is connected to the outside via the front opening 11a and the rear opening 11b.

The scanning device 50 has a pair of scanning rails 51, a carriage 52, a drive belt 53, and a scanning motor 54, and moves the head unit 12 in the left-right direction. The pair of scanning rails 51 are long members extending in the left-right direction, and are arranged parallel to each other so as to sandwich the head unit 12 between them in the front-rear direction. The carriage 52 carries the head unit 12 and is supported so as to be transportable in the left-right direction along the scanning rails 51. The drive belt 53 is an endless belt that extends along the scanning rails 51 in the left-right direction, is connected to the carriage 52, and is linked to the scanning motor 54 via a pulley. The scanning motor 54 drives the drive belt 53, causing the carriage 52 to move back and forth in the left-right direction along the scanning rails 51.

The transport device 60 has a stage 61, a pair of transport rails 62, a stage support base 63, and a transport motor 64 (Figure 2). The ejection receiving medium A is placed on the upper surface of the stage 61, and defines the distance between the ejection receiving medium A and the head 20 in the vertical direction. The pair of transport rails 62 extend in the front-rear direction, penetrate the housing 11, protrude forward from the front opening 11a, and protrude rearward from the rear opening 11b. The stage support base 63, for example, removably supports the stage 61, is supported so as to be movable in the front-rear direction along the pair of transport rails 62, and is connected to the transport motor 64. The transport motor 64 drives the stage support base 63 to move the stage 61 in the front-rear direction.

The head unit 12 has one or more heads 20. When there are multiple heads 20, the multiple heads 20 are arranged in the front-to-rear direction. A tank is connected to the head 20, and liquid is supplied from the tank to the head 20.

As shown in FIG. 2, the head unit 12 includes, in addition to the heads 20, fixing units 30 and mist collection units 40 in the same number as the heads 20. The heads 20 include a driving element 21, the fixing units 30 include a light source 31, and the mist collection units 40 include a fan motor 41a. The head unit 12 will be described in detail later.

<Configuration of the control device>
2, the control device 70 is connected to the drive element 21 via the head drive circuit 22 and controls the drive of the drive element 21. The control device 70 is connected to the light source 31 via the light source drive circuit 32 and controls the drive of the light source 31. The control device 70 is connected to the fan motor 41a via the fan drive circuit 42 and controls the drive of the fan motor 41a. The control device 70 is connected to the scan motor 54 via the scan drive circuit 55 and controls the drive of the scan motor 54. The control device 70 is connected to the transport motor 64 via the transport drive circuit 65 and controls the drive of the transport motor 64.

The control device 70 has a calculation unit 71 and a storage unit 72. The storage unit 72 is a memory accessible by the calculation unit 71, and is composed of RAM, ROM, etc. The RAM temporarily stores various data such as print jobs. The ROM stores programs for performing various data processing.

The calculation unit 71 is composed of a processor such as a CPU, and an integrated circuit such as an ASIC. The calculation unit 71 executes a program stored in the ROM to control the drive element 21, the light source 31, the fan motor 41a, the scanning motor 54, and the transport motor 64, and executes the printing process. The printing process will be described in detail later.

<Head unit configuration>
3 and 4, in the head unit 12, the head 20, the mist collection unit 40, and the fixing unit 30 are arranged in that order from left to right. For example, in the case of unidirectional printing in which the head 20 ejects liquid when it moves to the left and does not eject liquid when it moves to the right, the fixing unit 30 and the mist collection unit 40 are disposed upstream (right side) of the head 20 in the movement direction (left side) during printing. Therefore, the fixing unit 30 and the mist collection unit 40 move following the head 20 that ejects liquid.

The head 20 is connected to a carriage 52 (FIG. 1) by a connecting portion 56, and has a plurality of nozzles 23, a plurality of individual flow paths 24, a common flow path 25, a flow path forming body 26, and a plurality of driving elements 21 (FIG. 2). The plurality of nozzles 23 are arranged in a row at a predetermined interval in the front-rear direction to form a nozzle row, and further, the plurality of nozzle rows are arranged at a predetermined interval from each other in the left-right direction. The nozzle row may be inclined with respect to the front-rear direction.

The flow path forming body 26 is, for example, a rectangular parallelepiped shape, and has nozzles 23, individual flow paths 24, and a common flow path 25 formed therein, with the nozzles 23 opening on its lower surface (discharge surface 20a). The common flow path 25 extends in the front-rear direction and is connected to a tank. The multiple individual flow paths 24 are provided by branching off from the common flow path 25. The upstream ends of the individual flow paths 24 are connected to the common flow path 25, and the downstream ends are connected to the nozzles 23. The multiple nozzles 23 that make up the nozzle row are mutually connected to the same common flow path 25. Thus, liquid is supplied from the tank to the common flow path 25, and while flowing in the front-rear direction through the common flow path 25, it is diverted to the individual flow paths 24 and supplied to the nozzles 23.

The driving element 21 is a piezoelectric element or the like, and is provided corresponding to the individual flow path 24. The driving element 21 is driven by the control device 70 (Figure 2) to change the volume of the individual flow path 24. This applies pressure to the liquid in the individual flow path 24 to eject the liquid from the nozzle 23. This liquid is hardened by the energy of light.

The fixing unit 30 has multiple light sources 31, a cover 33, a light source board 34, and a case 35. The light sources 31 are, for example, LEDs, and are arranged on the underside of the light source board 34. The light sources 31 emit light (for example, ultraviolet light) that hardens the liquid that is ejected from the nozzles 23 and lands on the ejection medium A. The cover 33 is transparent so that the light from the light sources 31 can pass through, and is attached to the case 35 so as to cover the multiple light sources 31. The light source board 34 is equipped with the multiple light sources 31 and a light source drive circuit 32 (Figure 2). The case 35 houses the light sources 31 and the light source board 34.

The mist collection section 40 is disposed between the head 20 and the fixing section 30 in the left-right direction. The mist collection section 40 extends above the head 20 and the fixing section 30, and its upper end is disposed above the upper end of the head 20 and the upper end of the fixing section 30.

The mist collection unit 40 has an air flow path 43 through which air flows. The air flow path 43 has an intake port 43a for drawing in air and an exhaust port 43b for exhausting air. The intake port 43a is provided at one end of the air flow path 43, has edges that intersect (e.g., perpendicular) in the vertical direction, and faces downward relative to the air flow path 43. The intake port 43a is disposed between the ejection surface 20a of the head 20 and the light source 31 of the fixing unit 30 in the horizontal direction.

The exhaust port 43b is provided at the other end of the air flow path 43, and has edges that intersect (e.g., perpendicular) in the left-right direction. The exhaust port 43b opens closer to the head 20 side than the fixing unit 30 side in the air flow path 43, and faces left with respect to the air flow path 43. The exhaust port 43b is located above the top end of the head 20 in the vertical direction, and at least a portion of it is located above the top end of the fixing unit 30.

5 and 6, the air flow path 43 is cylindrical with a hollow portion, and air flows through this hollow portion. The air flow path 43 has an inner surface (inner wall) that forms a hollow portion inside, and an outer surface (outer wall) on the opposite side. The outer wall is exposed to the outside of the air flow path 43. The air flow path 43 has a first portion 44, a corner portion 45, and a second portion 46, and is tubular in shape bent at the corner portion 45. Note that in the example of FIG. 5, the air flow path 43 is bent at the corner portion 45 by 90 degrees, but the bending angle is not limited to this. For example, the air flow path 43 may be bent at the corner portion 45 at an angle greater than 90 degrees (obtuse angle) or less than 90 degrees (acute angle).

The corner portion 45 is provided between the intake port 43a and the exhaust port 43b in the air flow path 43. The first portion 44 extends in a first direction from the intake port 43a to the corner portion 45, and the second portion 46 extends in a second direction that intersects with the first direction from the corner portion 45 to the exhaust port 43b. Note that the first direction is referred to as "up" and the second direction is referred to as "left", but the arrangement of the mist collection unit 40 is not limited to this.

The first portion 44 is, for example, cylindrical in shape with a rectangular cross section perpendicular to the vertical direction, and has a first left wall 44a, a first right wall 44b, a first front wall 44c, and a first rear wall 44d. These are flat plates whose lower ends surround the suction port 43a and extend upward from the lower ends. The inner surface of the first right wall 44b (first inner wall 44b1) and the inner surface of the first left wall 44a (second inner wall 44a1) face each other, and the second inner wall 44a1 is closer to the head 20 than the first inner wall 44b1. The first front wall 44c and the first rear wall 44d are arranged between the first left wall 44a and the first right wall 44b with their inner surfaces facing each other and parallel to each other, and connect their edges.

The first portion 44 has a straight pipe portion 44e and an expanded diameter portion 44f in the vertical direction. The straight pipe portion 44e has a constant cross section perpendicular to the vertical direction throughout, and its lower end is connected to the upper end of the expanded diameter portion 44f. In the straight pipe portion 44e, the first inner wall 44b1 and the second inner wall 44a1 are arranged parallel to each other.

The enlarged diameter portion 44f has an intake port 43a at its lower end, and a cross section perpendicular to the vertical direction expands downward. In the enlarged diameter portion 44f, the first right wall 44b extends in the vertical direction, and the first left wall 44a is inclined relative to the first right wall 44b so as to extend downward and to the left.

Therefore, the first inner wall 44b1 is flat and extends upward from the suction port 43a through the enlarged diameter portion 44f and the straight pipe portion 44e. The second inner wall 44a1 is parallel to the first inner wall 44b1 in the straight pipe portion 44e, and is inclined to the left relative to the first inner wall 44b1 as it extends downward in the enlarged diameter portion 44f, and extends toward the head 20 below the connecting portion 56. This second inner wall 44a1 may be formed of a linearly inclined flat surface, or may be formed of a curved surface. When the second inner wall 44a1 is inclined linearly, it may be inclined while changing the inclination angle in stages.

The second portion 46 is, for example, cylindrical in shape with a rectangular cross section perpendicular to the left direction, and has a second upper wall 46a, a second lower wall 46b, a second front wall 46c, and a second rear wall 46d. These are flat plates whose left ends surround the periphery of the discharge port 43b and extend from the left end to the right. The second upper wall 46a and the second lower wall 46b are arranged parallel to each other with their inner surfaces facing each other. The second front wall 46c and the second rear wall 46d are arranged between the second upper wall 46a and the second lower wall 46b with their inner surfaces facing each other and parallel to each other, connecting their edges.

The corner portion 45 has a lower end connected to the upper end of the first portion 44 and a left end connected to the right end of the second portion 46. The corner portion 45 has an opening 45a, a third right wall 45b, a third front wall 45c, a third rear wall 45d, and a connecting plate 45e. The third front wall 45c is connected to the first front wall 44c and the second front wall 46c, which are arranged on the same plane as each other. The third rear wall 45d is connected to the first rear wall 44d and the second rear wall 46d, which are arranged on the same plane as each other.

The third right wall 45b is connected to the first right wall 44b. The third right wall 45b has an inner surface (opposing surface 45f) connected to the first inner wall 44b1. The first inner wall 44b1 and the opposing surface 45f are arranged on the same plane inside the air flow path 43, are flat, and are perpendicular to the left-right direction. The opposing surface 45f intersects (e.g., is perpendicular to) the left-right direction and faces the exhaust port 43b in the left-right direction with the filter 48 in between.

The third right wall 45b has an outer surface (third right outer surface) opposite the opposing surface 45f, and the first right wall 44b has an outer surface (first right outer surface) opposite the first inner wall 44b1. The third right outer surface and the first right outer surface are disposed on the same plane outside the air flow path 43, are flat, and are perpendicular to the left-right direction. At least a portion of the third right outer surface and the first right outer surface face the fixing section 30 (Figure 4).

The opening 45a opens at the upper end of the corner portion 45 and has a size that allows the holder 49 to pass through. The opening 45a is provided on the opposite side of the air flow path 43 from the intake port 43a in the vertical direction, and is disposed between the second upper wall 46a and the connecting plate 45e in the left-right direction. The periphery surrounding the opening 45a is formed by the right end of the second upper wall 46a, the upper end of the third right wall 45b, the upper end of the third front wall 45c, and the upper end of the third rear wall 45d.

The connecting plate 45e is flat and protrudes to the right from the upper end of the third right wall 45b, and is disposed at the same height as the second upper wall 46a in the vertical direction. The connecting plate 45e is provided with a first fixing hole 45g for fixing the holder 49 to the air flow path 43, and the first fixing hole 45g penetrates the connecting plate 45e in the vertical direction.

The mist collection section 40 includes an air flow path 43, a collection section 47, a filter 48, a holder 49, and a fan 41. The collection section 47 is provided on the first right wall 44b, and collects liquid adhering to the first inner wall 44b1 of the first right wall 44b. The collection section 47 has a through hole 47a, a guide plate 47b, two protrusions 47c, an absorber 47d, and a receiving section 47e.

The through hole 47a is provided in the enlarged diameter portion 44f of the first part 44, extends longitudinally, and penetrates the first right wall 44b in the transverse direction between the first inner wall 44b1 and the first right outer surface.

The protrusions 47c protrude from the first inner wall 44b1 and have an elongated shape. The two protrusions 47c are arranged above the through-hole 47a with a gap between them in the left-right direction. These protrusions 47c are provided in pairs at the front and rear, and are arranged in a V-shape so that they approach each other downward when viewed in the left-right direction, and their bottom ends are spaced apart. The through-hole 47a is located below the bottom ends of these protrusions 47c.

The guide plate 47b protrudes to the left from the lower edge of the through hole 47a and extends upward. When the guide plate 47b is viewed from the left, the guide plate 47b is positioned at a distance from the through hole 47a so that the guide plate 47b overlaps the through hole 47a.

The receiving portion 47e is disposed outside the air flow path 43 and is attached to the first right outer surface of the first right wall 44b below the through hole 47a. The receiving portion 47e is box-shaped with an open upper end and an internal space.

The absorber 47d is formed of a porous material such as a sponge, and has, for example, a rectangular parallelepiped shape. The absorber 47d is fitted into the receiving portion 47e so as to cover the through-hole 47a. The inner surface of the absorber 47d contacts the first right outer surface, and the upper surface of the absorber 47d is disposed above the through-hole 47a.

The filter 48 is formed of a porous material such as a sponge, has a rectangular parallelepiped shape, and is disposed in the air flow path 43 so as to cover the exhaust port 43b. The filter 48 has a right surface (filter surface 48a), a left surface 48b, and a side surface 48c.

The filter surface 48a faces the opposing surface 45f of the corner portion 45 and is farther from the outlet 43b in the left-right direction than the left surface 48b. The left surface 48b is the surface opposite the filter surface 48a. The filter surface 48a and the left surface 48b are flat. However, the filter surface 48a and the left surface 48b may be curved or have irregularities.

The filter surface 48a has a first end 48d in the up-down direction and a second end 48e located above the first end 48d. The first end 48d is closer to the intake port 43a than the second end 48e in the up-down direction, and closer to the exhaust port 43b than the second end 48e in the left-right direction. The first end 48d is located in the second portion 46 of the air flow path 43, and is located on the second lower wall 46b within the second portion 46. The lower surface of the filter 48 faces the second lower wall 46b.

The second end 48e is located to the right of the first end 48d and within the corner portion 45 of the air flow path 43. In the corner portion 45, the second end 48e is closer to the opening 45a in the up-down direction than the first end 48d, and closer to the opposing surface 45f in the left-right direction than the first end 48d. Therefore, the filter surface 48a is inclined upward and to the right so as to approach the opposing surface 45f from the first end 48d toward the second end 48e.

In the left-right direction, the distance between the second end 48e and the right end (opposing surface 45f) of the corner portion 45 is narrower than the distance between the second end 48e and the left end of the corner portion 45. For example, the distance between the second end 48e and the opposing surface 45f is less than half the dimension of the corner portion 45 in the left-right direction, and is less than half the dimension of the first portion 44 in the left-right direction (the distance between the first inner wall 44b1 of the first right wall 44b and the second inner wall 44a1 of the first left wall 44a).

The side surface 48c extends between and connects the filter surface 48a and the left surface 48b along their peripheries. The side surface 48c has an upper surface, a lower surface, a front surface, and a rear surface. The upper surface faces the opening 45a and slopes downward from the upper end of the left surface 48b toward the second end 48e of the filter 48, sloping downward and to the right. This leaves a gap between the second end 48e and the periphery of the opening 45a.

The holder 49 has, for example, a left holding plate 49a, a lower holding plate 49b, a right holding plate 49c, a covering portion 49d, and a handle portion 49e, which hold the filter 48 so that it can be detached from the air flow path 43 via the opening 45a. The left holding plate 49a, the lower holding plate 49b, the right holding plate 49c, the covering portion 49d, and the handle portion 49e are flat.

The left holding plate 49a contacts and supports the left surface 48b of the filter 48. The left holding plate 49a is disposed between the filter 48 and the fan 41, and has a circulation hole 49f in the area facing the fan 41. Because the circulation hole 49f penetrates the left holding plate 49a, air that has passed through the filter 48 passes through the circulation hole 49f and is drawn into the fan 41.

The left end of the lower holding plate 49b is connected to the lower end of the left holding plate 49a, and extends from there to the right in a direction perpendicular to the left holding plate 49a, contacting and supporting the lower surface of the filter 48. The lower end of the right holding plate 49c is connected to the right end of the lower holding plate 49b, and extends from there to the upper side in a direction perpendicular to the lower holding plate 49b, contacting and supporting the right surface of the filter 48. In the vertical direction, the right holding plate 49c is shorter than the left holding plate 49a and is positioned below the circulation hole 49f. As a result, the left holding plate 49a, the lower holding plate 49b, and the right holding plate 49c cover the lower part of the filter 48, allowing air to pass through the filter 48 and the circulation hole 49f.

The left end of the covering portion 49d is connected to the upper end of the left retaining plate 49a and extends to the right from there. The left region of the covering portion 49d covers the upper surface of the filter 48 and is positioned on the periphery of the opening 45a of the air flow path 43, blocking the opening 45a and forming the upper wall of the air flow path 43.

The right region of the covering portion 49d is disposed on the connecting plate 45e. This covering portion 49d has a second fixing hole 49g at a position corresponding to the first fixing hole 45g of the connecting plate 45e, and the second fixing hole 49g passes through the connecting plate 45e in the vertical direction. The holder 49 is fixed to the air flow path 43 by inserting a bolt 49h into the first fixing hole 45g and the second fixing hole 49g and tightening the bolt 49h with a nut 49i.

The handle 49e is provided in the right region of the covering 49d that corresponds to the connecting plate 45e, and its lower end is connected to the rear end of the covering 49d and rises upward from there. The user can attach the holder 49 to the air flow path 43 by gripping the handle 49e and inserting the holder 49 into the air flow path 43 from the opening 45a. The user can also remove the holder 49 from the air flow path 43 by gripping the handle 49e and pulling the holder 49 out of the air flow path 43 from the opening 45a.

A guide 43c for attaching and detaching the holder 49 is provided in the air flow path 43. The guide 43c is located in a corner portion 45 in the air flow path 43, below the opening 45a and to the right of the second portion 46. The guide 43c is provided, for example, on each of the inner surfaces of the third front wall 45c (third front inner surface) and the inner surface of the third rear wall 45d (third rear inner surface) that face each other. The guide 43c protrudes rearward from the third front inner surface, and protrudes forward from the third rear inner surface. The guide 43c extends diagonally downward to the left.

As a result, when the holder 49 is inserted into the air flow path 43 from the opening 45a, the lower right corner of the holder 49 abuts against the guide 43c and is guided along the guide 43c to a predetermined position in the second part 46. The holder 49 is supported by the guide 43c at a predetermined position. On the other hand, when the holder 49 is lifted up to remove the holder 49 from the air flow path 43 through the opening 45a, the lower right corner of the holder 49 is guided along the guide 43c to the opening 45a. Therefore, the holder 49 can be easily attached to and detached from the air flow path 43 by moving the holder 49 up and down.

The fan 41 has a rotating shaft 41b, multiple blades 41c, an intake port 41d, and an exhaust port 41e, and thus draws air containing the mist of liquid ejected from the head 20 into the air flow path 43. The fan 41 is disposed within the second portion 46.

The rotating shaft 41b crosses (for example, is perpendicular to) the vertical direction and is inclined with respect to the vertical direction so that it is upward toward the left. The rotating shaft 41b is connected to the fan motor 41a (Figure 2) and rotates when driven by the fan motor 41a. The multiple blades 41c are connected to the rotating shaft 41b and rotate around the rotating shaft 41b.

The intake port 41d faces the left surface 48b of the filter 48 through the flow hole 49f of the holder 49. The intake port 41d is to the left of the outlet port 41e and is arranged so as to sandwich the rotation shaft 41b between them in the left-right direction. The outlet port 41e is arranged outside the exhaust port 43b of the air flow path 43. However, the outlet port 41e may be arranged inside the air flow path 43 further than the exhaust port 43b.

<Printing process>
In such a liquid ejection device 10, as shown in Fig. 2, the control device 70 controls the scanning motor 54 to perform a movement operation that moves the head unit 12 in the left-right direction. The control device 70 also controls the drive element 21 to perform a discharge operation that causes the head 20 to eject liquid. The control device 70 controls the light source 31 to perform an application operation that causes the light source 31 to apply light. Furthermore, the control device 70 controls the transport motor 64 to perform a transport operation that transports the ejection receiving medium A backward by a predetermined amount. The liquid ejection device 10 then alternates between an image recording process including a movement process, a discharge process, and an application process, and a transport process to proceed with the printing process.

In this image recording process, as shown in FIG. 4, the head 20 moves to the left by the carriage 52 while ejecting liquid from the nozzles 23 of the head 20 onto the ejection receiving medium A. As a result, the liquid lands on the ejection receiving medium A on the stage 61, which faces the ejection surface 20a of the head 20. In addition, the fixing unit 30 applies light from the light source 31 while moving to the left following the head 20. As a result, light is applied to the liquid on the ejection receiving medium A facing the light source 31, and the liquid hardens due to the light and is fixed on the ejection receiving medium A. As a result, an image is formed on the ejection receiving medium A by the liquid.

In addition, during the image recording process, the mist collection unit 40 moves to the left behind the head 20 while the fan 41 is driven. As a result, air containing liquid mist ejected from the head 20 is sucked into the air flow path 43 from the intake port 43a of the mist collection unit 40. In this air flow path 43, the air flows upward through the first portion 44, changes direction at the corner portion 45, and flows to the second portion 46. At the corner portion 45 and the second portion 46, the air passes through the filter 48, and the mist contained in the air is collected by the filter 48. Then, the air passes through the fan 41 from the intake port 41d to the outlet port 41e in the second portion 46, and is discharged from the exhaust port 43b.

In addition, because air from the head 20 flows into the first portion 44 from the left side of the mist collection section 40 through the intake port 43a, the mist contained in the air tends to adhere to the first inner wall 44b1 of the first right wall 44b of the first portion 44. In addition, when the air flow direction changes from top to left at the corner portion 45, a convection current flows to the right, and the mist contained in the convection current adheres to the opposing surface 45f.

As a result, the mist adhering to the first inner wall 44b1 and the opposing surface 45f liquefies, and the liquid flows downward along the opposing surface 45f and the first inner wall 44b1. This liquid flows down along the protrusion 47c on the first inner wall 44b1 toward the through hole 47a, and is guided to the through hole 47a. In addition, the liquid that passes through the through hole 47a from top to bottom is guided to the through hole 47a by the guide plate 47b. Therefore, the liquid is guided to the through hole 47a and passes through the through hole 47a. The liquid is then absorbed and collected by the absorber 47d that covers the through hole 47a, and is received by the receiver 47e.

In this way, the mist collection unit 40 collects the mist from the head 20 using the filter 48 and the collection portion 47. This reduces the adhesion of mist to the fixing unit 30, which is located upstream of the mist collection unit 40 in the movement direction, and suppresses the decrease in the intensity of the light from the light source 31 of the fixing unit 30 caused by the mist. It also reduces the amount of liquid flowing down from the mist collection unit 40, and suppresses the liquid from contaminating the ejection medium A, etc.

<Action and Effects>
In the liquid ejection device 10, the filter surface 48a faces the opposing surface 45f, and has a first end 48d close to the suction port 43a in the first direction and a second end 48e far from the suction port 43a in the second direction. In the second direction, the second end 48e is closer to the opposing surface 45f than the first end 48d.

With this configuration, the gap between the filter surface 48a and the opposing surface 45f is narrower on the second end 48e side than on the first end 48d side. This reduces the space for convection in this gap, making convection more difficult. This reduces the amount of mist contained in the convection, and reduces the amount of liquid that adheres to the opposing surface 45f due to convection and flows down from the mist collection section 40.

In addition, at the corner portion 45, the filter surface 48a is inclined so as to approach the opposing surface 45f from the first end 48d toward the second end 48e, and faces the intake port 43a side in the vertical direction. Therefore, air flows from the intake port 43a toward the filter surface 48a and flows into the filter 48. The filter surface 48a into which the air flows is large, and the mist contained in the air is efficiently collected by the filter 48. This reduces the mist contained in the convection current, and reduces the liquid that adheres to the opposing surface 45f due to the convection current and flows down from the mist collection section 40.

Furthermore, the distance between the first end 48d and the opposing surface 45f is wider than the distance between the second end 48e and the opposing surface 45f. Therefore, even if the collected liquid accumulates on the first end 48d side of the filter 48, the air flowing in from the intake port 43a can flow through the distance between the first end 48d and the opposing surface 45f and into the corner portion 45. Therefore, the mist contained in the air can be collected by the second end 48e side of the filter 48 at the corner portion 45.

In the liquid ejection device 10, the filter 48 has a rectangular parallelepiped shape. When the filter 48 holds the captured mist, the captured mist moves to the bottom of the filter 48 by gravity. When the amount of mist held per unit volume of the filter 48 exceeds a threshold value, air becomes difficult to flow through the filter 48. For this reason, some parts of the filter 48 may have difficulty in allowing air to flow through them. For example, a filter 48 that is triangular when viewed from the front with corners facing downwards has a lower part with a smaller volume than the upper part, and compared to a rectangular parallelepiped filter 48, the lower part may have difficulty in allowing air to flow through it even when holding a small amount of mist.

In contrast, when the filter 48 is rectangular, the volume of the upper part above the center of the filter 48 in the vertical direction is equal to the volume of the lower part below the center. For this reason, the rectangular filter 48 is less likely to have difficulty in allowing air to flow through the lower part of the filter 48 compared to a filter 48 that is triangular when viewed from the front and has corners facing downward. Also, the filter 48 has a larger volume at the lower part compared to a filter 48 that is triangular when viewed from the front and has corners facing downward, so it can adequately retain the collected mist and reduce the amount of liquid that flows down from the mist collection unit 40.

In the liquid ejection device 10, the first end 48d of the filter 48 is disposed in the second portion 46. With this configuration, the filter 48 can ensure a passage for airflow along the first direction at the corner portion 45. In addition, the liquid collected by the filter 48 remains in the second portion 46, and the amount of liquid that flows down from the mist collection section 40 can be reduced.

In the liquid ejection device 10, the first direction is a bottom-to-top direction, and the liquid ejection device 10 is provided with a holder 49 that holds the filter 48. The holder 49 covers the lower part of the filter 48. With this configuration, the holder 49 can protect the filter 48. The holder 49 also prevents the liquid collected by the filter 48 from leaking from the filter 48, and can reduce the amount of liquid that flows down from the mist collection section 40.

In the liquid ejection device 10, the air flow path 43 has an opening 45a through which the holder 49 can pass, and a guide 43c that is provided on the inner surface of the air flow path 43 and guides the holder 49 that has passed through the opening 45a. With this configuration, the filter 48 held by the holder 49 can be replaced by attaching and detaching the holder 49 to and from the air flow path 43 through the opening 45a. This allows the filter 48 to fill with liquid collected by the filter 48, reducing leakage from the filter 48.

In the liquid ejection device 10, the filter 48 has a side surface 48c that extends along the periphery of the filter surface 48a. The holder 49 has a covering portion 49d that covers the side surface 48c on the second end 48e side and the opening 45a, and a handle portion 49e that protrudes from the covering portion 49d. A gap is provided between the second end 48e and the periphery of the opening 45a.

With this configuration, when the covering portion 49d is placed on the peripheral portion of the opening 45a to cover the opening 45a, a gap is provided between the second end 48e of the filter 48 and the peripheral portion of the opening 45a. This prevents the second end 48e of the filter 48 from being pinched between the covering portion 49d and the peripheral portion.

In the liquid ejection device 10, the first portion 44 has an expanded diameter portion 44f. The expanded diameter portion 44f has a first inner wall 44b1 extending in a first direction from the suction port 43a, and a second inner wall 44a1 that is closer to the head 20 than the first inner wall 44b1. The second inner wall 44a1 extends toward the suction port 43a in the opposite direction to the first direction, approaching the head 20.

With this configuration, the suction port 43a is expanded toward the head 20 by the expanded diameter portion 44f. This reduces the gap between the head 20 and the mist collection unit 40, reducing the diffusion of mist in this gap, and the mist collection unit 40 can efficiently suck in the mist through the suction port 43a.

In addition, in the enlarged diameter portion 44f, the second inner wall 44a1 is inclined relative to the first inner wall 44b1. Therefore, the air flowing in from the intake port 43a gradually changes its flow direction along the second inner wall 44a1. This reduces the occurrence of backflow and allows the air to flow smoothly through the first portion 44, allowing the mist collection section 40 to efficiently suck in the mist.

The liquid ejection device 10 includes a carriage 52 that carries the head 20 and moves back and forth in the second direction and the direction opposite to the second direction, and a connecting portion 56 that connects the head 20 and the carriage 52. The first direction extends upward. The second inner wall 44a1 of the expanded diameter portion 44f is disposed below the connecting portion 56. With this configuration, the mist that accumulates below the connecting portion 56 can be collected by the mist collection portion 40.

The liquid ejection device 10 is provided with a collection portion 47 that is provided on the first inner wall 44b1 and collects liquid that has adhered to the first inner wall 44b1. With this configuration, the collection portion 47 receives the liquid that adheres to the first inner wall 44b1 and flows down, thereby reducing the amount of liquid that flows down from the mist collection section 40.

In the liquid ejection device 10, the first direction extends upward. The collection portion 47 has a through hole 47a penetrating the first inner wall 44b1, and a receiving portion 47e located below the through hole 47a on the outer surface of the enlarged diameter portion 44f, which is opposite the first inner wall 44b1 in the second direction.

With this configuration, the mist that has adhered to the opposing surface 45f due to convection is liquefied and flows down along the opposing surface 45f and the first inner wall 44b1. At this time, the liquid passes through the through hole 47a provided in the first inner wall 44b1 and flows into the receiving portion 47e. This makes it possible to reduce the amount of liquid that flows down from the mist collection section 40.

The first inner wall 44b1 side of the first right wall 44b serves as a passage for air containing mist, and a receiving portion 47e is provided on the first outer right surface of the first right wall 44b. This prevents the receiving portion 47e from affecting the air flow.

In the liquid ejection device 10, the collection portion 47 includes an absorber 47d that is fitted into the receiving portion 47e and covers the through-hole 47a. With this configuration, the liquid that flows down along the opposing surface 45f and the first inner wall 44b1 is collected in the absorber 47d through the through-hole 47a. This makes it possible to reduce the amount of liquid that flows down from the mist collection section 40.

In addition, since the absorber 47d is provided on the first right outer surface of the first right wall 44b, it is possible to reduce the absorption of mist before the filter 48. This reduces the risk of the mist liquefying and filling the absorber 47d, causing leakage from the absorber 47d or the receiving portion 47e.

In the liquid ejection device 10, the head 20 ejects a liquid that hardens when energy is applied to it. The liquid ejection device 10 is provided with a fixing unit 30 that is disposed on the opposite side of the head 20 across the mist collection unit 40 and that applies energy to the liquid ejected onto the ejection receiving medium A. With this configuration, the mist collection unit 40 is disposed between the head 20 and the fixing unit 30, and can reduce adhesion of the mist from the head 20 to the fixing unit 30.

<Other Modifications>
In the above embodiment, the fixing unit 30 uses the light source 31 as a source for generating energy to fix the liquid on the ejection receiving medium A, but the source is not limited to this. For example, a heater that applies energy such as heat may be used as the source. Examples of heaters include a radiant heater, a hot air heater, and a contact heater. For example, the contact heater is provided on a roller. The roller heated by the contact heater comes into contact with the back surface of the ejection receiving medium A and fixes the liquid on the front surface of the ejection receiving medium A.

In this case, the liquid ejected from the head 20 is a liquid that is fixed to the ejection receiving medium A by energy such as heat, and for example, latex ink is used. Also, the fixing unit 30 does not need to be provided with a cover 33.

Also, for example, an energy generating device that generates radio waves such as microwaves may be used as the generation source. In this case, the liquid ejected from the head 20 is a liquid that is fixed on the ejection medium A by the energy of the microwaves, etc.

In the above embodiment, the second portion 46 extends to the left from the corner portion 45, but the direction in which the second portion 46 extends from the corner portion 45 is not limited to this. The second portion 46 may extend from the corner portion 45 in an upper left direction or a rear left direction, or may extend from the corner portion 45 to the right as shown in FIG. 7. In this case, the corner portion 45 has a third left wall 45h instead of the third right wall 45b. The inner surface of this third left wall 45h is the opposing surface 45h1 that faces the filter surface 48a in the left-right direction. The lower end of this opposing surface 45h1 is connected to the upper end of the second inner wall 44a1 and is disposed on the same plane as the second inner wall 44a1.

In the above embodiment, the filter 48 has a rectangular parallelepiped shape. However, the shape of the filter 48 is not limited to this as long as the second end 48e of the filter surface 48a is closer to the opposing surface 45f in the second direction than the first end 48d. For example, the filter 48 may have a triangular prism shape. In this case, the filter 48 has a triangular cross section that is perpendicular to the front-to-rear direction and has a smaller left-to-right dimension toward the bottom, and extends in the front-to-rear direction.

In the above embodiment, the collection portion 47 is provided on the first left wall 44, but the location of the collection portion 47 is not limited to this. The collection portion 47 may be provided on the first part 44 in the walls of the first right wall 44b, the first front wall 44c, the first rear wall 44d, etc. In this case, the through hole 47a of the collection portion 47 may penetrate the wall of the first part 44, and the absorber 47d and the receiving portion 47e may be provided on the outer surface of the wall, and the guide plate 47b and the convex portion 47c may be provided on the inner surface. This can reduce the liquid flowing down from the mist collection portion 40.

All of the above embodiments may be combined with one another as long as they do not exclude one another. Furthermore, many improvements and other embodiments of the present invention will be apparent to those skilled in the art from the above description. Therefore, the above description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode for carrying out the present invention. Details of the structure and/or function of the present invention may be substantially modified without departing from the spirit of the present invention.

The liquid ejection device and mist collection unit of the present invention are useful as liquid ejection devices and mist collection units that can reduce the amount of liquid that flows down from the mist collection unit.

10: Liquid ejection device 20: Head 30: Fixing unit 31: Light source (source of generation)
40: Mist collecting section 43: Air flow path 43a: Intake port 43b: Exhaust port 43c: Guide 44: First portion 44a1: Second inner wall 44b1: First inner wall 44f: Expanded diameter portion 45: Corner portion 45a: Opening 45f: Opposing surface 45h1: Opposing surface 46: Second portion 47: Collection portion 47a: Through hole 47d: Absorber 47e: Receiving portion 48: Filter 48a: Filter surface 48c: Side surface 48d: First end 48e: Second end 49: Holder 49d: Covering portion 49e: Handle portion 52: Carriage 56: Connection portion

Claims (14)

A head that ejects liquid onto an ejection receiving medium;
A mist collection unit for collecting the mist of the liquid,
The mist collection unit has an air flow path through which air flows, and a filter disposed in the air flow path and having a filter surface,
the air flow path has an intake port for taking in the air, an exhaust port for exhausting the air, a corner portion provided between the intake port and the exhaust port, a first portion extending in a first direction from the intake port to the corner portion, and a second portion extending in a second direction intersecting the first direction from the corner portion to the exhaust port,
The corner portion has opposing surfaces that intersect with the second direction,
A liquid ejection device, wherein the filter surface faces the opposing surface and has a first end closer to the suction port in the first direction and a second end farther from the suction port, the second end being closer to the opposing surface in the second direction than the first end. The liquid ejection device according to claim 1, wherein the filter has a rectangular parallelepiped shape. The liquid ejection device according to claim 1 or 2, wherein the first end of the filter is disposed in the second portion. a carriage on which the head is mounted and which reciprocates in the second direction and a direction opposite to the second direction;
4. The liquid ejection device according to claim 1, wherein the head ejects the liquid onto the ejection receiving medium when the carriage moves in the second direction. The first direction is a bottom-to-top direction,
A holder for holding the filter is provided.
5. The liquid ejection device according to claim 1, wherein the holder covers a lower portion of the filter. A head that ejects liquid onto an ejection receiving medium;
A mist collection unit for collecting the mist of the liquid,
The mist collection unit has an air flow path through which air flows, and a filter disposed in the air flow path and having a filter surface,
the air flow path has an intake port for taking in the air, an exhaust port for exhausting the air, a corner portion provided between the intake port and the exhaust port, a first portion extending in a first direction from the intake port to the corner portion, and a second portion extending in a second direction intersecting the first direction from the corner portion to the exhaust port,
The first direction is a bottom-to-top direction,
A holder for holding the filter is provided.
The holder covers a lower portion of the filter,
The liquid ejection device, wherein the air flow path has an opening through which the holder can pass, and a guide provided on an inner surface of the air flow path for guiding the holder that has passed through the opening. A head that ejects liquid onto an ejection receiving medium;
A mist collection unit for collecting the mist of the liquid,
The mist collection unit has an air flow path through which air flows, and a filter disposed in the air flow path and having a filter surface,
the air flow path has an intake port for taking in the air, an exhaust port for exhausting the air, a corner portion provided between the intake port and the exhaust port, a first portion extending in a first direction from the intake port to the corner portion, and a second portion extending in a second direction intersecting the first direction from the corner portion to the exhaust port,
The corner portion has opposing surfaces that intersect with the second direction,
the filter surface faces the opposing surface and has a first end close to the suction port and a second end far from the suction port in the first direction;
The first direction is a bottom-to-top direction,
A holder for holding the filter is provided.
The holder covers a lower portion of the filter,
the air flow path has an opening through which the holder can pass, and a guide provided on an inner surface of the air flow path to guide the holder that has passed through the opening,
The filter has a side surface extending along a periphery of the filter surface,
the holder has a cover portion that covers the side surface of the second end side and the opening, and a grip portion that protrudes from the cover portion,
A liquid ejection device, wherein a gap is provided between the second end and a peripheral edge of the opening. the first portion having an expanded diameter portion;
the expanded diameter portion has a first inner wall extending in the first direction from the suction port and a second inner wall closer to the head than the first inner wall,
7. The liquid ejection device according to claim 1, wherein the second inner wall extends in a direction opposite to the first direction toward the suction port and approaches the head. A head that ejects liquid onto an ejection receiving medium;
A mist collection unit for collecting the mist of the liquid,
The mist collection unit has an air flow path through which air flows, and a filter disposed in the air flow path and having a filter surface,
the air flow path has an intake port for taking in the air, an exhaust port for exhausting the air, a corner portion provided between the intake port and the exhaust port, a first portion extending in a first direction from the intake port to the corner portion, and a second portion extending in a second direction intersecting the first direction from the corner portion to the exhaust port,
the first portion having an expanded diameter portion;
the expanded diameter portion has a first inner wall extending in the first direction from the suction port and a second inner wall closer to the head than the first inner wall,
the second inner wall extends toward the head as it moves toward the suction port in a direction opposite to the first direction,
a carriage on which the head is mounted and which reciprocates in the second direction and a direction opposite to the second direction;
a coupling portion that couples the head and the carriage,
The first direction extends upward,
A liquid ejection device, wherein the second inner wall of the expanded diameter portion is disposed below the connecting portion. A head that ejects liquid onto an ejection receiving medium;
A mist collection unit for collecting the mist of the liquid,
The mist collection unit has an air flow path through which air flows, and a filter disposed in the air flow path and having a filter surface,
the air flow path has an intake port for taking in the air, an exhaust port for exhausting the air, a corner portion provided between the intake port and the exhaust port, a first portion extending in a first direction from the intake port to the corner portion, and a second portion extending in a second direction intersecting the first direction from the corner portion to the exhaust port,
the first portion having an expanded diameter portion;
the expanded diameter portion has a first inner wall extending in the first direction from the suction port and a second inner wall closer to the head than the first inner wall,
the second inner wall extends toward the head as it moves toward the suction port in a direction opposite to the first direction,
A liquid ejection device comprising: a collection portion provided on the first inner wall, the collection portion collecting the liquid adhering to the first inner wall. The first direction extends upward,
The liquid ejection device described in claim 10, wherein the collection portion has a through hole penetrating the first inner wall, and a receiving portion located below the through hole and on the outer surface of the enlarged diameter portion, the receiving portion being located on a surface opposite the first inner wall in the second direction. The liquid ejection device according to claim 11, wherein the collection portion includes an absorbent body that is fitted into the receiving portion and covers the through hole. The liquid ejection device according to any one of claims 1 to 12, further comprising a fixing unit disposed on the opposite side of the head side across from the mist collection unit, and fixing the liquid ejected from the head onto the ejection receiving medium. The suction port is provided at an end portion of the first portion opposite to the corner portion in the first direction,
The liquid ejection device according to any one of claims 1 to 13, wherein the outlet is provided at an end of the second portion opposite to the corner portion in the second direction .