Patent Application
20170120609
Field of the Invention
The present invention relates to a printing apparatus that performs a printing operation by ejecting ink onto a printing medium and a liquid storage member used in a printing apparatus.
Description of the Related Art
For a conventional ink jet printing apparatus, there is a configuration including a head that ejects ink, an ink tank that stores ink, and an ink flow path that connects the head and the ink tank (Japanese Patent Laid-Open No. 2010-208151). The ink tank has a buffer tank communicating with the atmosphere and is designed so that air flows into the ink tank from the buffer tank in the case where ink is consumed in the head.
In the ink jet printing apparatus described in Japanese Patent Laid-Open No. 2010-208151, the opening of a communication flow path through which the ink tank and the buffer tank communicate within the buffer than is arranged under an ejection port surface of the head so as to prevent ink from leaking out of the head. Due to the configuration such as this, the interior of the head is maintained in the negative pressure state by a hydraulic head difference.
In the field of the ink jet printing apparatus, there exists an ink jet printing apparatus including an injection port through which ink can be injected into an ink tank from the top of the ink tank. In the ink jet printing apparatus such as this, it is difficult to maintain the negative pressure state within the head by making use of the hydraulic head difference as in Japanese Patent Laid-Open No. 2010-208151.
That is, in the configuration of the ink jet printing apparatus described in Japanese Patent Laid-Open No. 2010-208151, the injection port is provided on the top of the ink tank and in the case where the injection port opens, the ink tank is caused to communicate with the atmosphere via the injection port. In this case, there is a possibility that the ink within the ink tank leaks out to the outside through the buffer tank and the atmosphere communication port of the buffer tank.
An object of the present invention is to provide a printing apparatus or a liquid storage member that suppresses ink from leaking out to the outside at the time of ink injection in a configuration in which an injection port is provided to an ink tank. The printing apparatus of the present invention includes a print head that performs a printing operation by ejecting a liquid, a liquid storage container in which a liquid storage chamber that stores the liquid to be supplied to the print head, an atmosphere communication chamber that communicates with the atmosphere, and a communication flow path that causes the liquid storage chamber and the atmosphere communication chamber to communicate are formed integrally, and a liquid injection portion provided on the liquid storage container and configured to be injected the liquid into the liquid storage chamber from the outside, and the liquid storage container can take a first posture in which the atmosphere communication chamber is located under the liquid storage chamber in the direction of gravity and a second posture in which the atmosphere communication chamber and the liquid storage chamber are located side by side in the horizontal direction, and in the case where the posture of the liquid storage container is the second posture, the liquid injection portion and the communication flow path are located on the upper side of the liquid storage container.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
Hereinafter, embodiments of the present invention are explained in detail with reference to the attached drawings. Explanation is given by attaching the same symbols to the same configurations through each drawing. In the present embodiment, as a printing apparatus, a serial-type ink jet printing apparatus 11 (hereinafter, described as a “printing apparatus”) is explained as an example.
A carriage 12 receives a drive from the carriage motor 204 via the timing belt while being supported by the main chassis and moves along the main scanning direction perpendicular to the conveyance direction of a printing medium. Due to the configuration such as this, it is possible for the print head 13 to reciprocate along the main scanning direction together with a carriage 12. In the vicinity of the carriage 12, a code strip for detecting the position of the carriage 12 is installed in a stretched state in parallel to the timing belt. In the code strip, for example, markings are formed at a pitch of 150 to 300 per inch. On the other hand, on the carriage 12, an encode sensor for reading the code strip is mounted.
In the present embodiment, it is possible for the print head 13 to eject inks of four colors (cyan, magenta, yellow, black) and ejection units 131 each ejecting each of the inks of four colors are arranged in parallel to one another in the main scanning direction. The ejection unit 131 is formed by, for example, an ejection port (nozzle) corresponding to each of the inks of four colors and an ejection port formation surface, to be described later, refers to a surface on which the ejection port in the print head 13 is formed. The print head 13 prints an image by ejecting each ink to a printing medium based on image data input to the printing apparatus 11. The printing medium may be any medium on which an image can be formed by landing ink droplets. For example, it is possible to use those of various materials and in various forms, such as paper, cloth, an optical disk label surface, a plastic sheet, an OHP sheet, and an envelope. Further, the printing apparatus 11 includes an ink flow path 14 of each ink corresponding to the ink of each color of the print head 13 and can supply the ink of each color to the print head from the ink tank 15. The printing apparatus 11 of the present embodiment includes four kinds of ink tank: a tank for black 151, a tank for cyan 152, a tank for magenta 153, and a tank for yellow 154.
Further, the printing apparatus 11 includes a maintenance unit within a movement range in the scanning direction of the carriage 12. The maintenance unit includes a recovery unit configured to perform recovery processing of the print head 13 and is arranged so as to face the ejection unit 131, to be described later. The recovery unit includes a cap unit configured to cap the ejection unit 131 and a suction mechanism configured to forcibly suck in ink in the capped state to remove the residual bubbles and the ink of which the viscosity has been increased within the ejection unit 131. By the recovery processing of the recovery unit, the function of the print head 13 is recovered and at the same time, the ejection characteristics of the print head are maintained.
As shown in
The ink storage chamber 33 and the buffer space 34 communicate via a communication flow path 35. In the present embodiment, the ink storage chamber 33 and the buffer space 34 share part of the bottom surface of the ink storage chamber 33 so that the bottom surface serves as the ceiling surface of the buffer space 34. It can be said that the bottom surface of the ink storage chamber 33 and the ceiling surface of the buffer space 34 are partition walls 36 that define the ink storage chamber 33 and the buffer space 34.
As shown in
An ink outflow unit 141 communicates with the ink storage chamber 33 and supplies ink to the print head 13 by causing the ink to flow out. The ink outflow unit 141 is formed in the vicinity of the bottom surface of the ink storage chamber 33. The ink outflow unit 141 configures the liquid outflow unit in the present invention.
The buffer space 34 and the outside of the ink tank 15 communicate via an atmosphere communication flow path 23 including an atmosphere opening 24 that opens into the atmosphere. In the present embodiment, the atmosphere communication flow path 23 is arranged on the rear side of the ink tank 15 and the atmosphere opening 24 is arranged in the vicinity of the top of the ink tank 15. Due to the configuration such as this, in the case where the ink in the ink storage chamber 33 is consumed in the state of being hermetically closed by the tank cap 22, it is possible to take in the outside air via the atmosphere communication flow path 23 and the atmosphere opening 24. It is possible for the ink tank 15 of the present embodiment to store the ink in the buffer space 34, which is pushed out by the expanded air, in the case where the air within the ink storage chamber 33 expands due to the fluctuations in pressure or the change in temperature as in the case of the ink tank described in Japanese Patent Laid-Open No. 2010-208151. Due to the configuration such as this, it is possible to prevent the ink that is pushed out by the expanded air and which flows backward through the atmosphere communication flow path 23 from leaking out through the atmosphere opening 24.
In the present embodiment, at the time of ink injection, in the case where the liquid surface within the ink tank 15 is at a height position that does not exceed a height position (Zh) of the ejection port formation surface of the head in the second posture (see
Further, in the case where an open/close valve is provided in the ink flow path 14, it is no longer necessary to take into consideration the position (hydraulic head difference) of the ink tank at the time of ink injection, and it is also possible to more securely suppress the leakage of ink at the time of ink injection.
As shown in
In
The height of the ejection port formation surface, which is the arrangement surface on which the ejection units 131 are arranged side by side, is taken to be Zh and the lowest position in the ink flow path 14, which is the flow path connecting the ink outflow unit 141 and the print head 13, is taken to be Z0. In the present embodiment, the ink outflow unit 141 is provided at the position the height of which is the same as that of the bottom surface (partition wall surface of the partition wall 36) of the ink storage chamber 33.
Further, the height of the position of the opening 32 in the communication flow path 35 is taken to be Z1. At this time, the height Z1 corresponds to the liquid surface height of ink at which the gas-liquid exchange between the ink and the atmosphere is performed as the ink is consumed by the print head 13.
As described previously, the buffer space 34 is located under the ink storage chamber 33 in the direction of gravity, and therefore, the position (Z1) of the opening 32 is arranged on the lower side of the height (Zh) of the ejection port formation surface of the print head 13. Due to the configuration such as this, it is possible for the printing apparatus 11 of the present embodiment to cause a hydraulic head difference to occur between Zh and Z1 and to favorably keep the negative pressure within the print head 13. Further, in the printing apparatus 11 of the present embodiment, a meniscus is formed also in the ejection port (ejection unit 131), and therefore, the backflow of ink into the ink storage chamber 33 is prevented, which is caused by air being mixed through the ejection port.
The height Z2 of the ink liquid surface is arranged under the height (Zh) of the ejection port formation surface of the print head 13. Because of this, even in the case where the ink 19 is pushed out into the buffer space 34, the negative pressure within the print head 13 does not change reversely to the positive pressure immediately, and therefore, it is unlikely that the ink leaks out of the print head 13.
Further, by limiting the height (Z2) of the ink liquid surface in the buffer space 34 to the position (Z0) of the partition wall surface or lower, which is the surface of the partition wall 36, the height (Z2) is always lower than the height of the ejection port formation surface of the print head 13, and therefore, it is possible to stably keep the negative pressure within the print head.
By limiting the height (Z2) of the ink liquid surface in the buffer space 34 to the position (Z0) of the partition wall surface or lower and further setting the lowest position in the ink flow path 14 to the position (Z0) of the partition wall surface or higher, the ink flow path 14 will always be located at the position higher than the height (Z2) of the ink liquid surface. Because of this, even in the case where air is mixed within the ink flow path 14, it is possible to favorably keep the negative pressure within the print head. Due to the configuration such as this, it is possible for the printing apparatus 11 of the present embodiment to favorably keep the negative pressure within the print head 13 even in the case where ink is stored in the buffer space 34.
As explained above, it is possible for the ink tank 15 of the present embodiment to take the first posture in which the buffer space 34 is located under the ink storage chamber 33 in the direction of gravity and the second posture in which the buffer space 34 and the ink storage chamber 33 are located side by side in the horizontal direction. Due to the configuration such as this, it is unlikely for the printing apparatus 11 of the present embodiment to cause the atmosphere to communicate through the ink injection port in the state where the negative pressure in the print head 13 is kept favorably. Because of this, even in the case of a configuration in which the ink injection port 21 is provided to the ink tank 15, it is possible to suppress ink from leaking out to the outside at the time of ink injection.
As shown in
As shown in
As explained above, according to the printing apparatus 11 of the present embodiment, the effect that it is possible to provide a printing apparatus with good operability is obtained in addition to the effect by the first embodiment.
In the above-described embodiments, the aspect is explained in which the ink tank 15 stores one kind of ink in the one ink storage chamber 33 and in the one buffer space 34. However, the embodiments are not limited to those described above.
That is, as shown in
Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment (s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like.
According to the printing apparatus of the present invention, it is possible to suppress ink from leaking out to the outside at the time of ink injection in a configuration in which an injection port is provided to an ink tank.
While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.
This application claims the benefit of Japanese Patent Application No. 2015-214358, filed Oct. 30, 2015, which is hereby incorporated by reference wherein in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2015-214358 | Oct 2015 | JP | national |
