1. Field of the Invention
The invention relates to a liquid ejecting apparatus that is provided with a tank accommodation unit for accommodating sub-ink-tanks that are connected to a main ink tank through ink tubes.
2. Description of the Related Art
There are cases where ink jet printers must deal with the printing of relatively large amounts of ink. For example, as shown in Japanese Patent Laid-Open No. 2002-307712, there are cases where sub-ink-tanks are provided on a print head unit that has an ink ejection portion that ejects ink, and main ink tanks, which supply ink to the sub-ink-tanks, are provided separately on the main body of the printer. The sub-ink-tanks of the print head unit and the main ink tanks are connected by ink supply tubes that form ink supply pathways. Herewith, each of the inks from ink retention units of each of the main ink tanks is separately supplied to the sub-ink-tanks through the set of ink supply tubes.
And, for example, a serial ink jet printer carries out the printing of ink by way of the print head unit ejecting ink on the printing surface of a print medium while a carriage, in which the aforementioned print head unit is detachably mounted, moves back and forthwith respect to the print surface of the print medium. As for such serial printers, when performing the supply of ink to the print head unit, there are cases where a change of the ink pressure inside the print head unit occurs, due to acceleration and deceleration that comes along with back and forth movement of the carriage. In a case where an ink pressure variation has occurred, there is a danger that the ejection of ink at the ink ejection portion of the print head unit will become unstable. In particular, in the case where the carriage reciprocates at a high speed for the purpose of high speed printing, the influence of ink pressure variation, caused by acceleration and deceleration, becomes larger.
As a solution to this problem, as described in Japanese Patent Laid-Open No. 2002-307712, it is proposed to mount sub-ink-tanks in the print head unit, which sub-ink-tanks have pressure regulation parts that regulates ink pressure.
By way of providing a negative pressure generation mechanism as a pressure regulation part at the portion of the ink ejection unit of the print head unit that is on the upstream side, the ink ejection portion can eject ink without being effected by pressure variation of ink inside the print head unit, caused by the back and forth movement of the print head. Therefore, in printers of this type space is necessary for sub-ink-tanks to be disposed inside the print head unit.
In printers such as that mentioned above, a needle of a needle holding member provided at one end of a ink supply tube (see Japanese Patent Laid-Open No. 2002-307712), is capable of being inserted and removed, through a sealing member, into and out of a needle acceptance portion of the print head unit, which the needle acceptance portion is in communication with the sub-ink-tank. In the case where a replacement is necessary, for example, a case where a failure has occurred in the print head unit, or a case where the duration of use of the print head unit has reached its lifespan, in order to replace the print head unit, the needle of the needle holding member is removed from the needle acceptance portion of the print head unit. On the other hand, in the case of carrying out the connection of needles and the needle acceptance portion, through the sealing member, the full load, along the direction of insertion of the needle, which is caused by friction between the tips of each of the needles and each of the contacted surfaces of the sealing members, acts on the contour portion that forms the needle acceptance portion of the print head unit. In doing so, it is necessary that damage to the printer main body and the print head unit due to the insertion force of these needles, and problems such as ink leakage between the needles and the needle acceptance portions, does not occur.
Additionally, for example, as set forth in Japanese Patent Laid-Open No. 2006-255965, an apparatus is proposed wherein ink inside each of the main ink tanks is supplied to the print head unit through an ink supply tube group, via the pressurized air of a pressure pump.
In a case where the number of ink colors supplied to a print head unit such as the one described above is relatively small, the number of needles, and the number of sealing members at the needle acceptance portions of the sub-ink-tanks, are also small. Thus, at the time of the connection operation, the insertion force of the needles, which acts on the contour portion of the print head unit through the sealing member along the direction of insertion of the needle, is small.
However, with ink jet printers, there is a tendency for the number of ink colors supplied to the print head unit to increase as high image quality printing is demanded. In such cases the number of needles and sealing members also increases. As a result, in such cases a plurality of needle acceptance portions of the print head unit, and a plurality of needles, are connected through sealing members inside the needle acceptance portion. In this case, the resultant force of each of the needle insertion forces, which act along the direction of insertion on the portion of the contour portion of the print head unit at which the sealing member and the needle acceptance portion is provided (also referred to below as the connection end of the print head unit), increases in accordance with the growth of the number of ink colors.
And, in the case of dealing with high speed printing as mentioned above, there is a necessity to ensure space inside the print head unit for mounting sub-ink-tanks, because the sub-ink-tanks are disposed inside the print head unit. Thus, in this configuration, the number of sub-ink-tanks, which store each of the inks, increases as the number of ink colors increase. Because of this, the resultant force of each of the needle insertion forces that act on the connection end of the print head unit increases, and due to the resultant force of each of the insertion forces along the insertion direction of the needle, and insufficient strength of the connection end, there is a possibility that a damage may occur, such as the connection end bending greatly, thus deforming and a crack forming therein.
As a measure to prevent the aforementioned deformation of the connection end, a method has been considered wherein the strength of the connection end is increased by way of increasing the material thickness of the connection end or providing a plurality of beams that are parallel to the needle insertion direction at the space inside the print head unit. However, increasing the material thickness of the connection end, as well as increasing the number of beams, as mentioned above, causes a problem wherein the size of the print head unit increases, and as such is a inexpedient solution.
In light of the above problems, the present invention aims to provide a liquid ejection apparatus. The liquid ejection apparatus can increase the rigidity of a tank reception portion in accordance with the number of sub-ink-tanks, without an increase in the size of the liquid ejection apparatus.
In order to accomplish the above described object, the liquid ejection apparatus of the invention comprises: a print head that ejects ink, a sub-ink-tank that has an ink retention portion that retains the ink, an ink supply needle that that has an ink supply aperture formed therein that supplies ink to the sub-ink-tank, a tank accommodation unit that is connected to the sub-ink-tank and forms an ink flow path that is in communication with the ink retention portion, when the-sub-ink-tank is accommodated therein, a sealing member that seals an aperture that is connected to the ink flow path provided on the tank accommodation unit, and a plurality of fixation portions, which are for fixing the sub-ink-tank and the tank accommodation unit, and which include at least one fixation portion that is provided above the aperture, wherein the tank accommodation unit, which is pushed toward the sub-ink-tank by the ink supply needle that is inserted through the sealing member into the aperture, is pushed back, in the direction that is opposite to the insertion direction of the ink supply needle, by the plurality of fixation portions, which are disposed on the sub-ink-tank along a straight line extending along the longer direction of the sub-ink-tank.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
In
Although not shown in the figure, the main ink tanks 14 are disposed inside of an ink jet printer, for example. The main ink tank 14 have twelve small chambers 14A1 to 14A12 within tank cases 14C, and the small chambers each have structures that house one ink bag. The main ink tank 14 has twelve ink bags which are mounted in the small chamber, respectively. Each of the small chambers 14A1 to 14A12 inside the main ink tank 14 are in communication with each other through a communication pathway. A single pressure pump is connected to the communication pathway. Thus pressure inside the small chambers 14A1 to 14A12 is controlled by the common pump 18, through the communication pathway.
Operation of the pressure pump 18 is controlled by a control unit (omitted from the figure), based on the detected output from a pressure sensor provided in the ink supply tubes to be described later. The control unit, based on the detected output from the pressure sensor, supplies pressurized air, which is at a prescribed pressure, to the communication pathway via the pressure pump 18, such as to pressurize the ink bags 16IB1 to 161B12 inside the main ink tank with air. Herewith each of the inks inside the ink bags 16IB1 to 161B12, which are pressurized by the pressurized air, are supplied to the print head unit to be described later. That is, ink is stably supplied to the sub-ink-tanks also in the case of high speed printing, by way of each of the inks being supplied by pressure.
Prescribed amounts (for example, on the order of 40 cc) of grey ink, black ink, yellow ink, magenta ink, cyan ink, light ink of prescribed ink colors, and processing liquid, etc., are respectively housed inside the ink bags 16IB1 to 161B12.
A spout 20 is provided, as an ink supply port, on each of the ink bags 16IB1 to 161B12. With each of the ink bags 16IB1 to 161B12, the later described ink supply tubes 12T1 to 12T12 are detachably inserted into ends of the spouts, which are exposed to the peripheries of the each of the small chambers 14A1 to 14A12. When the end of an ink supply tube is connected to the spout 20, it is sealed with respect to the spout 20.
The other ends of the flexible ink supply tubes 12T1 to 12T12 are respectively connected to the tube connecting portion of the tube connecting connectors 22. As shown by
The ink supply needles 22N1 to 22N6, which communicate with the ports referred to above and are laid out with one pair for double file, are each formed such as to project from the other surface of the tube connecting connector 22 and to be inserted into apertures of the sub-ink-tanks.
The tube connecting connector 22 is detachable, along the direction shown by the arrows of
In the case where the tube connecting connector 22 is connected to the later described connection end 24SW of the sub-ink-tank accommodation unit 24 of the print head unit 10, a pair of the ink supply needles 22N1, 22N2, 22N3, 22N4, 22N5, and 22N6 respectively come close to the connection end 24SW at approximately the same time. As shown in
Also, as shown in
Herewith a pair of the ink supply needles 22N1 to 22N6 introduce each of the inks through the connection end 24SW and into each of the supply pathways, which communicate into the later described sub-ink tanks 26ST1 to 26ST6.
Explanation will be made with respect to the ink supply needle pairs 22N1, and explanation with respect to the other ink supply needles 22N2 to 22N6 of each pair will be omitted because the ink supply needles 22N1 to 22N6 of each pair have the same configuration as each other.
One ink supply needle among the ink supply needle pairs 22N1 is formed at a position that is offset, in the direction denoted by the X arrow of
As shown in
As shown in
The print head unit 10, as shown in
The aperture pairs 24a1 to 24a6 of the connection end 24SW correspond to the array of ink supply needle pairs 22N1 to 22N6 of the above described tube connecting connector 22, and are formed on a common surface. Thus, because the ink supply needle pairs 22N1 to 22N6 are disposed on a common surface, and the aperture pairs 24a1 to 24a6 are disposed on a common surface of the connection end 24SW that faces the tube connecting connector 22, a reduction in size of the tube connecting connector 22 is planned.
The respective aperture pairs shown in
A positioning hole 24THA, which fits together with the positioning pin 22PA, is formed below the right aperture (in upper row of apertures as seen in
A wiring board 28, which transmits a drive pulse signal group supplied through the carriage (see
As shown by
Sealing members SE are formed at each of the bottom portions of first ink retention chamber 26R1 and a second ink retention chamber 26R3 shown in
Explanation will be made with respect to the sub-ink-tank 26ST2, and explanation with respect to the other sub-ink-tanks 26ST1, 26ST3 to 26ST6 will be omitted because the sub-ink-tanks 26ST1 to 26ST6 have the same configuration as each other.
The sub-ink-tank 26ST2 has through-holes 26Tc and 26Td, which are for insertion of screws 32A and 32B, formed as sub-ink-tank-side fixation portions as shown in
As shown in
The mechanism by which ink is supplied to the sub-ink-tank 26ST2 and the mechanism by which ink is supplied from the sub-ink-tank 26ST2 will be explained next. Ink is supplied from the aforementioned right aperture (as seen in
The inks that have been supplied to the first retention chamber 26R1 and the second retention chamber 26R3 are respectively supplied, through filters FI, from the ink discharge pathways of the aforementioned ink retention portions 26R2 and 26R4 to the ink ejection unit 30. In the ink ejection unit 30, that ink is supplied to common liquid chambers (not shown) that correspond to the print element substrate for each ink color, used for ink ejection.
Generally, the respective colors of ink that are supplied through the apertures 24a1 to 24a6, are supplied, to the ink ejection unit 30 from the ink discharge pathways of the sub-ink-tanks 26ST1 to 26ST6. And, they are supplied to the ink ejection unit 30 along the direction shown by the arrows in
With respect to the above structure, a case of assembling the sub-ink-tanks 26ST1 to 26STS to the tank accommodation portion 24A will be explained. First, the positions of the each third fixation portions (the fitting holes) 26Tb of the sub-ink-tanks 26ST1 to 26ST6 are aligned with the connection pins 24P of the tank accommodation portion 24A. Next, the sub-ink-tanks 26ST1 to 26ST6 are inserted into the tank accommodation portion 24A until the first fixation portion (the through hole) 26Tc and the second fixation portion (the through hole) 26Td respectively touch the tank holder in side the tank accommodation portion 24A.
Next, the screw 32A and the screw 32B are respectively screwed through the first and second fixation portions (the through holes) 26Tc and 26Td into the threaded bores 24c and 24d.
In the case where, as shown in
In doing so, that insertion force is transmitted to the sub-ink-tanks 26ST1 to 26ST6 via the third fixation portion (the fitting hole) 26Tb and the connection pin 24P. Herewith, by way of being fixed by the first and second fixation portions (the through holes) 26Tc and 26Td, and the third fixation portion (the fitting hole) 26Tb, rigidity of the tank accommodation portion 24A is reinforced, the counteracting force, which works against the insertion force of the ink supply needles being inserted into the apertures, works effectively, and it is possible to restrain deformation of the connection end 24SW. Because of such reasons the connection end 24SW does not locally deform, due to deformation of the tank accommodation portion 24 being restrained, and due to it not being deformed, therefore the tips of the ink supply needles 22N1 to 22N6 are reliably inserted into the apertures and reliably sealed to the sealing member that seals the apertures, and it is possible to suppress the leakage of ink.
As an example for comparison, as shown in
When a plurality of ink supply needles 22N1 to 22N6 are inserted into the apertures of the tank accommodation portion, which has deformed in the above manner, several of the ink supply needles, among the plurality of ink supply needles, are not reliably inserted into the sealing member 24′r and the sealing there becomes inadequate. In such a case, when ink is supplied to the ink supply needles 22N1 to 22N6, there is a possibility that ink leakage will occur from the locations where sealing is inadequate.
According to the above described embodiment of the invention, it is possible to suppress, as described immediately above, ink supply needle insertion not being reliably sealed and the occurrence of ink leakage, caused by the tank accommodation portion 24A being pushed and deforming, by way of the existence of a plurality of fixation portions for fixing a sub-ink tanks 24 and the tank accommodation portion 24A, and there being at least one fixation portion at the region above the apertures into which the ink supply needles are inserted. It should be noted that the area that is described as the “region above” the apertures denotes the entire area of the sub-ink-tank end portion protruded through the tank holder of the tank accommodation portion 24A of a sub-ink-tank.
In the above example, the sub-ink-tanks 26ST1 to 26ST6 are fixed to the sub-ink-tank accommodation unit 24 by way of the screws 32A and 32B being screwed into holes. It should be noted that the fixation member is not limited to the above embodiment; for example, without using screws such as that of the above embodiment at the first and second fixation portions, fixation may be carried out by way of a stud holder and a nut.
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 Nos. 2010-192351, filed Aug. 30, 2010 and 2011-180741, filed Aug. 22, 2011 which are hereby incorporated by reference herein in their entirety.
Number | Date | Country | Kind |
---|---|---|---|
2010-192351 | Aug 2010 | JP | national |
2011-180741 | Aug 2011 | JP | national |