This application claims the priority benefit of Japan application serial no. 2021-096257 filed on Jun. 9, 2021. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
The invention relates to a printing apparatus performing printing on a recording medium.
In order to prevent ink clogging in a recording head, an inkjet printing apparatus performs a maintenance operation in which ink is idly discharged from the recording head.
Such printing apparatus includes a maintenance unit for collecting the ink idly discharged from the recording head (see, for example, Patent Document 1).
The maintenance unit has a roller provided below the recording head, a motor rotating the roller in a predetermined direction, and a scraper which is sheet-like and a tip of which linearly contacts the outer circumferential surface of the roller. In a state in which the roller rotates in the predetermined direction, the recording head idly discharges the ink toward the outer circumferential surface of the roller. The ink idly discharged from the recording head is attached to the outer circumferential surface of the roller. Through the rotation of the roller in the predetermined direction, when the ink attached to the outer circumferential surface of the roller arrives at the tip of the scraper, the ink is scraped off by the tip of the scraper. The ink that is scraped off drops from the outer circumferential surface of the roller, and is collected in a waste ink container provided below the roller.
[Patent Document 1] Japanese Laid-Open No. 2010-30273
In the printing apparatus, a pigment ink may be used as the ink for printing. In general, pigment ink is highly viscous and easily curable. When such pigment ink is used, the ink (pigment ink) scraped off from the outer circumferential surface of the roller does not drop from the outer circumferential surface of the roller, but is attached to and accumulates on the side surface of the scraper. When the ink accumulates and piles up on the side surface of the scraper, the ink that piles up overflows to the top of the roller and is attached to the recording head, which leads to the concern of causing printing defects.
A printing apparatus according to an aspect of the invention is a printing apparatus performing printing on a recording medium. The printing apparatus includes: a recording head, discharging ink to the recording medium; a roller, configured to collect ink which is idly discharged from the recording head and does not contribute to the printing on the recording medium, and having an outer circumferential surface configured for the ink idly discharged from the recording head to be attached; a drive source, rotating the roller in a predetermined direction; and a scraper, configured to scrape off the ink attached to the outer circumferential surface of the roller in a state in which the roller rotates in the predetermined direction. The scraper is provided with: a recessed surface, making surface contact with the outer circumferential surface of the roller; and a notch part, formed at an end of the recessed surface, making line contact with the outer circumferential surface of the roller, and recessed in a substantially V shape along a rotation direction of the roller and from the end of the recessed surface toward another end.
In
In order to achieve the objective, a printing apparatus according to an aspect of the invention is a printing apparatus performing printing on a recording medium. The printing apparatus includes: a recording head, discharging ink to the recording medium; a roller, configured to collect ink which is idly discharged from the recording head and does not contribute to the printing on the recording medium, and having an outer circumferential surface configured for the ink idly discharged from the recording head to be attached; a drive source, rotating the roller in a predetermined direction; and a scraper, configured to scrape off the ink attached to the outer circumferential surface of the roller in a state in which the roller rotates in the predetermined direction. The scraper is provided with: a recessed surface, making surface contact with the outer circumferential surface of the roller; and a notch part, formed at an end of the recessed surface, making line contact with the outer circumferential surface of the roller, and recessed in a substantially V shape along a rotation direction of the roller and from the end of the recessed surface toward another end.
According to the aspect, the notch part of the scraper is formed at the end of the recessed surface, and has a shape recessed in the substantially V shape along the rotation direction of the roller and from the end of the recessed surface toward the another end. In the state in which the roller rotates in the predetermined direction, the ink attached to the outer circumferential surface of the roller is scraped off by the notch part of the scraper. The predetermined direction refers to a direction in which the ink attached to the outer circumferential surface of the roller is scraped off by the scraper along the rotation direction of the roller. At this time, while being sequentially scraped off from the two ends of the notch part in the substantially V shape to the central part, the ink attached to the outer circumferential surface of the roller is collected at the central part of the notch part and then drops due to the own weight of the ink. Accordingly, by suppressing the ink scraped off from the outer circumferential surface of the roller from accumulating at the scraper, the ink can be suppressed from attaching to the recording head.
For example, in the printing apparatus according to an aspect of the invention, the recessed surface may make surface contact with the outer circumferential surface of the roller throughout an end of the roller in an axial direction to another end. In addition, the notch part may include: a first edge part, extending from the end of the roller in the axial direction toward a central part and from the end of the recessed surface toward the another end; and a second edge part, extending from the another end of the roller in the axial direction toward the central part and from the end of the recessed surface toward the another end.
According to the aspect, the first edge part and the second edge part of the notch part formed in the substantially V shape throughout the end to the another end in the axial direction of the roller can make line contact three-dimensionally with the outer circumferential surface of the roller. Accordingly, the ink attached to the outer circumferential surface of the roller can be effectively scraped off.
For example, in the printing apparatus according to an aspect of the invention, the scraper may be configured to be further provided with a suspended surface suspended from the notch part.
According to the aspect, while being sequentially scraped off from the two ends of the notch part in the substantially V shape to the central part, the ink attached to the outer circumferential surface of the roller is collected at the central part of the notch part and then dammed by the suspended surface. The ink dammed by the suspended surface drops from the suspended surface due to the own weight of the ink. Accordingly, the ink attached to the outer circumferential surface of the roller can drop effectively.
According to the printing apparatus according to an aspect of the invention, the ink scraped off from the outer circumferential surface of the roller can be suppressed from attaching to the recording head.
In the following, the embodiments of the invention will be described in detail with reference to the drawings. The embodiments described below are all inclusive or specific examples. The values, shapes, materials, components, positions where the components are provided, and connection configurations shown in the following embodiments are merely examples, and shall not be construed as limitations on the invention. In addition, among the components in the following embodiments, the components not described in the independent claims are described as arbitrary components.
(Embodiment)
[1. Outline of Printing Apparatus]
Firstly, a printing apparatus 2 of the embodiment is outlined with reference to
In
The printing apparatus 2 is an inkjet printing apparatus serving to perform printing by discharging ink to a recording medium 4. In the embodiment, the printing apparatus 2 is a so-called coupon printer for printing a coupon. The recording medium 4 is a roll paper wound like a roll, for example.
As shown in
An accommodation part 14 for accommodating the recording medium 4 wound like a roll is provided inside the housing 6. As shown in
As shown in
As shown in
An ink tank 22 and a recording head 24 are mounted in the carriage 20. The ink tank 22 is filled with four types of ink of CMYK (C: Cyan, M: Magenta, Y: Yellow, K: Black), for example. In addition, the ink filled in the ink tank 22 is pigment ink containing pigment as coloring agents. The recording head 24 is provided at the lower end of the carriage 20, and discharges mist-like ink of each color downward (minus Z-axis side) from the ink tank 22.
During execution of printing, the conveyance unit 8 conveys the recording medium 4 to from the accommodation part 14 to the discharge port 16, and the carriage 20 of the print unit 10 moves reciprocally along the guide frame 18. In such state, with the recording head 24 discharging ink toward the recording medium 4, the recording medium 4 is printed.
In addition, before execution of printing, a maintenance operation is performed to prevent ink clogging in the recording head 24. In the maintenance operation, the carriage 20 stops at a maintenance position (the position of the carriage 20 shown in
As shown in
[2. Configuration of Maintenance Unit]
Then, the configuration of the maintenance unit 12 according to the embodiment will be described with reference to
As shown in
The frame 26 supports the motor 28, the guide member 32, and the waste ink container 34, etc. The frame 26 is formed by pressing a sheet metal, for example.
The motor 28 is a drive source for rotating the roller 30. The motor 28 is supported by the frame 26 and connected to the roller 30 via a gear mechanism 36 and a shaft 38. The rotation driving force of the motor 28 is transmitted to the roller 30 via the gear mechanism 36 and the shaft 38.
The roller 30 collects the ink by transmitting the ink idly discharged from the recording head 24 toward the waste ink container 34. When the carriage 20 stops at the maintenance position, the roller 30 is provided right below the carriage 20. As shown in
An end of the roller 30 in the axial direction is connected with the shaft 38 (see
As shown in
The tubular part 42 guides the ink scraped off by the scraper 48 from the outer circumferential surface 30a of the roller 30 to the waste ink container 34. As shown in
As shown in
The scraper 48 scrapes off the ink attached to the outer circumferential surface 30a of the roller 30. The scraper 48 has a recessed surface 50, a notch part 52, and a suspended surface 54.
As shown in
As shown in
In the specification, “substantially V shape” refers to a shape that spreads out from the downstream side toward the upstream side in the predetermined direction. It is not required that each of a first edge part 52a and a second edge part 52b is a straight line. Each of the first edge part 52a and the second edge part 52b may also be a curved line. In addition, it is not required that the “substantially V shape” is a shape in left-right symmetry, but may also be a shape in left-right asymmetry.
More specifically, the notch part 52 includes the first edge part 52a and the second edge part 52b. An end of the first edge part 52a and an end of the second edge part 52b are connected with each other at the central part of the roller 30 in the axial direction.
The first edge part 52a linearly extends from the end of the roller 30 to the central part in the axial direction and from the end of the recessed surface 50 toward the other end (that is, from the upstream side toward the downstream side in the predetermined direction). In the XY plane view shown in
The second edge part 52b linearly extends from the other end of the roller 30 to the central part in the axial direction and from the end of the recessed surface 50 toward the other end (that is, from the upstream side toward the downstream side in the predetermined direction). In the XY plane view shown in
As shown in
In the following, the operation of scraping off the ink attached to the outer circumferential surface 30a of the roller 30 by using the scraper 48 is described with reference to
As shown in
Through the rotation of the roller 30 in the predetermined direction, when the ink attached to the outer circumferential surface 30a of the roller 30 arrives at the notch part 52, the ink is scraped off by the notch part 52. Specifically, as shown in an arrow Q in a broken line in
In addition, as shown in an arrow R in a broken line in
By doing so, after being collected at the central part from the two ends of the notch part 52, the ink scraped off from the outer circumferential surface 30a of the roller 30 is dammed by the suspended surface 54 as shown in
In the following, the configuration of a maintenance unit according to a comparative example is described with reference to
As shown in
The scraper 106 is formed in a sheet shape, and is supported in a bent shape by the protrusions 104 of the tubular part 102. An edge part 106a formed at the upper end of the scraper 106 is formed in a linear shape and makes line contact with the outer circumferential surface 30a of the roller 30. The scraper 106 is formed by resin, such as polyethylene terephthalate (PET), for example.
As shown in (a) of
Through the rotation of the roller 30 in the predetermined direction, when the ink attached to the outer circumferential surface 30a of the roller 30 arrives at the edge part 106a of the scraper 106, the ink is scraped off by the edge part 106a. At this time, the ink attached to the outer circumferential surface 30a of the roller 30 is uniformly scraped off throughout an end of the edge part 106a to the other end in the length direction (Y-axis direction). Therefore, as shown in (a) of
Then, when the roller 30 further rotates in the predetermined direction, as shown in (b) of
Then, when the roller 30 further rotates in the predetermined direction, as shown in (c) of
Comparatively, in the printing apparatus 2 according to the embodiment, the notch part 52 of the scraper 48 is formed at the end of the recessed surface 50 on the upstream side in the predetermined direction, and has a recessed shape that is substantially V-shaped from the upstream side toward the downstream side in the predetermined direction. In the state in which the roller 30 rotates in the predetermined direction, the ink attached to the outer circumferential surface 30a of the roller 30 is scraped off by the notch part 52 of the scraper 48.
At this time, a portion of the ink attached to the outer circumferential surface 30a of the roller 30 drops from the outer circumferential surface 30a of the roller 30 due to the own weight of the ink while being sequentially scraped off from the two ends of the notch part 52 in the substantially V shape to the central part. In addition, another portion of the ink attached to the outer circumferential surface 30a of the roller 30 is collected at the central part of the notch part 52 and then drops due to the own weight of the ink, while being sequentially scraped off from the two ends of the notch part 52 in the substantially V shape to the central part. Accordingly, by suppressing the ink scraped off from the outer circumferential surface 30a of the roller 30 from accumulating at the scraper 48, the ink can be suppressed from attaching to the recording head 24.
(Modified Example 1)
A guide member 32A according to Modified Example 1 is described with reference to
As shown in
(Modified Example 2)
A guide member 32B according to Modified Example 2 is described with reference to
As shown in
Even in such configuration, effects same as the above embodiment can still be obtained.
In the modified example, the notch part 52B includes two edge parts (the first edge part 52Ba and the second edge part 52Bb) in a substantially V shape. However, the invention is not limited thereto, and the notch part may include three or more edge parts in a substantially V shape.
(Other Modified Examples)
The printing apparatus according to the embodiments and the modified examples of the invention have been described above. However, the printing apparatus according to the invention is not limited thereto.
In the above embodiments and examples, the recording medium 4 is a roll paper. However, the invention is not limited thereto. For example, the recording medium 4 may also be a plain paper, a photo paper, or a compact disc read only memory (CD-ROM) having a printable label surface.
The printing apparatus according to the embodiment can be suitable as an inkjet printer performing printing by discharging ink to a recording medium, for example.
Number | Date | Country | Kind |
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2021-096257 | Jun 2021 | JP | national |
Number | Name | Date | Kind |
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20100002048 | Masaoka | Jan 2010 | A1 |
20210213734 | Martin | Jul 2021 | A1 |
Number | Date | Country |
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2010030273 | Feb 2010 | JP |
Number | Date | Country | |
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20220396075 A1 | Dec 2022 | US |