JP3800034B2 - Inkjet recording device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ink jet recording apparatus including a recording head that discharges ink supplied from an ink cartridge as ink droplets.
[0002]
[Prior art]
In general, ink used in an ink jet recording apparatus is obtained by uniformly dispersing and mixing dispersed particles such as pigment and toner in a solvent. Such an ink has a property that printing is not performed for a long period of time, and when the ink is not circulated in the ink storage unit, the dispersed particles descend and precipitate due to the specific gravity difference between the solvent and the dispersed particles. .
[0003]
In order to keep the concentration constant against the precipitation of such dispersed particles, it has been studied to provide a stirring device. For example, in the ink jet printing apparatus disclosed in Japanese Patent Application Laid-Open No. 5-229140, in order to effectively stir ink having high viscosity or pigment having a high specific gravity, a stirring blade and an ink jet vane are provided in the ink storage unit. A rotation shaft for imparting rotation is provided and rotated by a drive motor from outside the ink storage unit.
[0004]
However, since the above apparatus employs a structure in which the ink storage unit is provided with a stirring blade and a rotary shaft, there is a problem that the ink storage unit is increased in size by the drive unit including the stirring blade and the rotary shaft. Further, when the amount of ink falls below a certain amount in the ink storage section, the function of the stirring blade is reduced by half, and a sufficient stirring effect cannot be expected. Further, the rotation of the stirring blade causes a flow of ink in a certain direction in the ink storage unit, and depending on the shape of the inner wall surface of the ink storage unit, ink stagnation tends to occur near the inner wall surface.
[0005]
In order to solve such a problem, for example, an electrostatic ink jet recording apparatus disclosed in Japanese Patent Laid-Open No. 10-286562 has been devised. In this recording apparatus, a pair of opposed stirring electrodes are arranged inside the ink storage unit, and the polarity is changed by applying an AC voltage for a certain period of time. As a result, even when the charged toner is precipitated in the ink storage unit, the charged toner precipitated due to the change in the polarity of the stirring electrode repeatedly moves to the low voltage side, and the precipitated charged toner has a stirring action, so that the ink with a constant concentration is obtained. It becomes.
[0006]
[Problems to be solved by the invention]
However, the ink jet recording apparatus stirs ink by changing the polarity by applying an alternating voltage to the pair of stirring electrodes provided in the ink storage portion for a certain period of time. There is a problem that a controller for applying an AC voltage to the stirring electrode is required, and the apparatus becomes complicated and large. In addition, since a pair of agitation electrodes must be provided in the ink reservoir, and the agitation electrode and the controller must be electrically connected, the structure of the ink reservoir itself becomes complicated and large, and an increase in cost can be avoided. In addition, there is a limit to the amount of ink that can be stored. For this reason, it is actually difficult to apply to a relatively small recording apparatus using a replaceable ink cartridge.
[0007]
The present invention has been made in view of such circumstances, and an ink jet recording apparatus capable of preventing sedimentation by stirring ink stored in a replaceable ink cartridge without complicating or increasing the size of the ink cartridge. The purpose is to provide.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, an ink jet recording apparatus of the present invention stores a recording head that ejects ink droplets in response to a print signal, and ink that is detachably mounted on the recording head and supplied to the recording head. And an ink agitating means for agitating the ink in the ink cartridge mounted on the recording head, the ink jet recording apparatus comprising: A carriage for reciprocating movement, and the ink agitating means moves the magnetic member provided in the ink chamber of the ink cartridge and the magnetic member provided in any part of the region including the moving range of the carriage in the vertical direction. The gist is to have a magnetic member moving means for moving.
[0018]
In the ink jet recording apparatus of the present invention, when the magnetic member moving means is a magnet provided such that the height thereof changes with respect to the moving direction of the carriage, the magnetic member moves as the carriage reciprocates. It is possible to effectively prevent sedimentation by stirring the ink stored in the replaceable ink cartridge that moves in the ink chamber.
[0019]
In the ink jet recording apparatus of the present invention, when the magnetic member moving means is at least one magnet provided in an area including the moving range of the carriage, the magnetic member is moved along with the reciprocating movement of the carriage. The ink that moves indoors and is stored in the replaceable ink cartridge can be agitated to effectively prevent sedimentation.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail.
[0021]
FIG. 1 is a diagram showing an example of the peripheral structure of the ink jet recording apparatus of the present invention. This apparatus includes an ink cartridge (hereinafter referred to as “cartridge”) 2 and a carriage 3 to which a recording head 1 is attached.
[0022]
The carriage 3 is connected to a stepping motor 5 via a timing belt 4 and is guided by a guide bar 6 to reciprocate in the paper width direction (main scanning direction) of the recording paper 7. The carriage 3 has a box shape that opens to the top, and is attached so that the nozzle surface of the recording head 1 is exposed on the surface facing the recording paper 7 (the lower surface in this example), and the cartridge 2 is accommodated. It has become.
[0023]
Then, ink is supplied from the cartridge 2 to the recording head 1 and ink droplets are ejected onto the upper surface of the recording paper 7 while moving the carriage 3 so that images and characters are printed on the recording paper 7 in a dot matrix. .
[0024]
In the figure, reference numeral 8 denotes a cap that prevents the nozzles from being dried as much as possible by sealing the nozzles of the recording head 1 during a printing pause. The cap 8 also functions as an ink receiver during a flushing operation in which ink droplets are forcibly ejected from the nozzles at regular intervals during printing. Reference numeral 9 denotes a wiper member for wiping the nozzle surface of the recording head 1.
[0025]
FIG. 2 is a sectional view showing an embodiment of the ink jet recording apparatus of the present invention. As shown in the figure, the carriage 3 has a generally box shape that opens to the upper surface as a whole, and the cartridge 2 is accommodated therein. The recording head 1 is attached to the carriage 3 so that the nozzle surface is exposed on the lower surface.
[0026]
A positioning member 24 is provided at the bottom of the carriage 3 to fit the ink supply unit 13 formed on the lower surface of the cartridge 2 to position the cartridge 2. On the upper surface of the positioning member 24, an ink supply needle 14 is provided which is inserted into the ink supply unit 13 and receives supply of ink supplied from the cartridge 2 to the recording head 1.
[0027]
In the figure, reference numeral 10 denotes a guide hole through which the guide bar 6 is inserted to guide the carriage 3. Further, the front and rear side surfaces (left and right in the figure) of the cartridge 2 are engaged with engaging portions 25 and 26 provided at the front and rear of the upper opening edge of the carriage 3 to fix the cartridge 2 to the carriage 3. Members 11 and 12 are formed.
[0028]
The carriage 3 is provided with a heater 15 that abuts the bottom surface of the cartridge 2 and heats the ink in the cartridge 2 at the bottom. In addition, at least a portion of the cartridge 2 that is in contact with the heater 15 is provided with an ink chamber 17 that contains liquid and flowable ink that is not held by an ink holder such as a porous material.
[0029]
With such a configuration, in the ink jet recording apparatus, the bottom of the cartridge 2 is heated by the heater 15 provided in the carriage 3 to heat the ink in the vicinity of the bottom in the ink chamber 17 to generate convection. The ink in 17 can be stirred. In this way, the ink in the cartridge 2 is agitated not by the cartridge 2 but by the heater 15 provided in the carriage 3 of the recording apparatus, so that the replaceable cartridge 2 can be obtained without complicating and increasing the size of the cartridge 2. The ink stored in the container can be agitated to effectively prevent the ink from settling.
[0030]
In the above embodiment, the heater 15 is provided in contact with the bottom surface of the ink chamber 17, but the present invention is not limited to this, and the heater 15 is provided in contact with the side surface in the vicinity of the bottom of the ink chamber 17. You can also.
[0031]
FIG. 3 is a plan view showing an ink jet recording apparatus according to the second embodiment of the present invention. In this recording apparatus, the cartridge 2 is provided with an ink chamber 17 (see FIG. 4) in which liquid and fluid ink that is not held by an ink holding member such as a porous material is stored. In this example, the cartridge 2 stores magnetic ink containing magnetic particles 20 (see FIG. 4).
[0032]
In the recording apparatus, the magnet 16A that moves the magnetic ink in the cartridge 2 within the cartridge 2 to the rear side of the left end carriage 3 and the front side of the right end carriage 3 within the movement range T of the carriage 3, respectively. , 16B are provided to generate a magnetic field in a region around the magnets 16A, 16B. As a result, the force for moving the magnetic ink in the ink cartridge 2 varies depending on the location. In FIG. 3, reference numeral 19 denotes a paper feed roll for feeding the recording paper 7 in a direction perpendicular to the moving direction of the carriage 3. Other than that, it is the same as that of the said embodiment, and the same code | symbol is attached | subjected to the same part.
[0033]
With this configuration, in the ink jet recording apparatus, as shown in FIG. 4, when printing is performed by reciprocating the carriage 3, the magnetic particles 20 in the ink chamber 17 are moved when the carriage 3 moves to the left end. Is attracted to the left end magnet 16A and moved backward, and when the carriage 3 is moved to the right end on the opposite side, the magnetic particles 20 in the ink chamber 17 are attracted to the right end magnet 16B and moved forward. .
[0034]
Thus, the magnetic ink in the ink chamber 17 can be agitated by alternately moving the magnetic particles 20 from one to the other as the carriage 3 reciprocates. As described above, since the ink in the cartridge 2 is agitated not by the cartridge 2 but by the magnets 16A and 16B provided in the moving range T of the carriage 3 of the recording apparatus, the structure of the cartridge 2 is complicated and enlarged. In addition, the ink stored in the replaceable cartridge 2 can be agitated to effectively prevent the ink from settling.
[0035]
FIG. 5 is an explanatory diagram showing an ink jet recording apparatus according to a third embodiment of the present invention. In this recording apparatus, one magnet 16 is provided above the carriage 3 on one end side of the movement range of the carriage 3. Other than that, it is the same as the above embodiments, and the same reference numerals are given to the same parts.
[0036]
In this apparatus, when the carriage 3 moves to the end where the magnet 16 is provided, the magnetic particles 20 in the ink chamber 17 are attracted to the magnet 16 and move upward, and the carriage 3 moves to another position. Then, the magnetic particles 20 moved upward start to settle due to their own weight. Thus, the magnetic ink in the ink chamber 17 can be agitated by repeatedly moving the magnetic particles 20 upward.
[0037]
In this case, the magnet 16 is preferably provided at the end opposite to the end where the cap 8 is provided. By doing so, since the stay time of the carriage 3 is long on the cap 8 side, the magnetic particles 20 moved upward attracted to the magnet 16 are sufficiently settled and stirred at the position of the carriage 3. . Other than that, it is the same as that of each said embodiment, and there exists the same effect.
[0038]
In the recording apparatus of the second embodiment, the example in which the magnets 16A and 16B provided on the left and right ends are respectively arranged on the rear side and the front side of the carriage 3 has been described. However, the present invention is not limited to this. It can also be provided on the upper and lower sides of the carriage 3.
[0039]
In the recording apparatus, the two magnets 16A and 16B are arranged at the left and right end portions in the movement range T of the carriage 3, respectively. However, the present invention is not limited to this. Any of these locations can be arranged as appropriate. Furthermore, in the second and third embodiments, the magnetic field generating means for generating a magnetic field is not limited to the magnets 16, 16A, 16B, and a coil or the like can be used.
[0040]
FIG. 6 is an explanatory diagram showing an ink jet recording apparatus according to a fourth embodiment of the present invention. In this recording apparatus, a pair of electromagnets 16 </ b> C and 16 </ b> D is provided on one end side of the movement range of the carriage 3 so as to sandwich the carriage 3. The electromagnets 16C and 16D are connected to polarity inversion means 28 for appropriately inverting the polarity. Other than that, it is the same as the above embodiments, and the same reference numerals are given to the same parts.
[0041]
In this recording apparatus, the force for moving the magnetic particles 20 is reversed by reversing the polarity of the pair of electromagnets 16C and 16D sandwiching the ink cartridge 2 by the polarity reversing means 28. Along with this reversal, the magnetic particles 20 are alternately moved from one to the other to stir the magnetic ink in the ink chamber 17.
[0042]
FIG. 7 is an explanatory diagram showing an ink jet recording apparatus according to a fifth embodiment of the present invention. In this recording apparatus, the cartridge 2 has an ink chamber 17 in which ink that is in a liquid and flowable state and is not held by an ink holder such as a porous material is accommodated. In this example, the cartridge 2 stores charged ink containing charged particles 21.
[0043]
In the recording apparatus, a pair of charged bodies 22 are provided at positions where the carriage 3 is sandwiched from the front and the rear at the left end portion and the right end portion within the movement range of the carriage 3, respectively. An electric field is generated. In the figure, reference numeral 27 denotes a power supply device for applying a voltage to the charging body 22.
[0044]
The charging body 22 provided at the left end portion of the charging bodies 22 in each of the above groups has a charging body 22 that is negatively charged on the front side of the carriage 3 and a charging body 22 that is positively charged on the rear side of the carriage 3. Is arranged. On the other hand, the charging member 22 provided at the right end portion has a positively charged charging member 22 disposed on the front side of the carriage 3 and a negatively charging member 22 disposed on the rear side of the carriage 3. Other than that, it is the same as the above embodiments, and the same reference numerals are given to the same parts.
[0045]
With such a configuration, in the above-described ink jet recording apparatus, when printing is performed by reciprocating the carriage 3, the charged particles 21 in the ink chamber 17 are charged on the left end side when the carriage 3 moves to the left end. Attracted to move. At this time, the positively charged particles 21 of the charged particles 21 are attracted to the negatively charged charged body 22 and moved forward, and the negatively charged particles are attracted to the positively charged charged body 22 and moved backward. Moving.
[0046]
Conversely, when the carriage 3 moves to the right end on the opposite side, the charged particles 21 in the ink chamber 17 are attracted to the charged body 22 on the right end side and move. At this time, the positively charged particles 21 of the charged particles 21 are attracted to the negatively charged charged body 22 and moved backward, and the negatively charged particles are attracted to the positively charged charged body 22 and moved forward. Moving.
[0047]
Thus, the charged ink in the ink chamber 17 can be agitated by alternately moving the charged particles 21 from one to the other. In this way, since the ink in the cartridge 2 is agitated not by the cartridge 2 but by the charging member 22 provided within the movement range T of the carriage 3 of the recording apparatus, the structure of the cartridge 2 is not complicated and enlarged. The ink stored in the replaceable cartridge 2 can be agitated to effectively prevent the ink from settling.
[0048]
In the recording apparatus, the voltage applied to the pair of charging bodies 22 at a position where the carriage 3 is sandwiched from the front and rear can be appropriately reversed. By doing this, the charged ink in the ink chamber 17 can be stirred by reversing the force for moving the charged particles 21 and alternately moving the charged particles 21 from one to the other.
[0049]
FIG. 8 is a front view showing an ink jet recording apparatus according to the sixth embodiment of the present invention. In this recording apparatus, the cartridge 2 is provided with an ink chamber 17 (see FIG. 9) that accommodates liquid and flowable ink that is not held by an ink holder such as a porous material. In the ink chamber 17, for example, a magnetic member 23 attracted to a magnet such as an iron piece or a stainless steel piece is movably accommodated.
[0050]
Further, the recording apparatus is provided with a bar-shaped magnet 18 provided so that its height changes with respect to the moving direction of the carriage over substantially the entire moving range T of the carriage 3. Other than that, it is the same as the above embodiments, and the same reference numerals are given to the same parts.
[0051]
With this configuration, in the ink jet recording apparatus, as shown in FIG. 9, when printing is performed by reciprocating the carriage 3, the magnetic member 23 in the ink chamber 17 is moved when the carriage 3 moves to the left end. Is attracted to the magnet 18 and moves downward. As the carriage 3 moves to the right, the magnetic member 23 in the ink chamber 17 is attracted to the magnet 18 and gradually moves upward. On the contrary, when the carriage 3 moves to the left, the magnetic member 23 in the ink chamber 17 is attracted by the magnet 18 and gradually moves downward.
[0052]
Thus, the ink in the ink chamber 17 can be stirred by repeatedly moving the magnetic member 23 up and down. Thus, since the ink in the cartridge 2 is agitated not by the cartridge 2 but by the magnet 18 provided in the moving range T of the carriage 3 of the recording apparatus, the cartridge 2 can be replaced without complicating or increasing the size of the cartridge 2. The ink stored in the possible cartridge 2 can be agitated to effectively prevent ink settling.
[0053]
FIG. 10 is an explanatory diagram showing an ink jet recording apparatus according to a seventh embodiment of the present invention. In this recording apparatus, a plurality of short magnets 18 are provided over substantially the entire length of the movement range T of the carriage 3 so that the height changes stepwise with respect to the movement direction of the carriage 3. The rest is the same as in the fifth embodiment, and the same reference numerals are given to the same parts. This recording apparatus also has the same function and effect as the fifth embodiment.
[0054]
In the recording apparatuses of the sixth and seventh embodiments, the magnet 18 is provided so that its height changes with respect to the moving direction of the carriage 3. However, the present invention is not limited to this. It is also possible to provide the angle so that the angle changes in the horizontal rear direction with respect to the three moving directions. In this case, the same effect can be obtained.
[0055]
FIG. 11 is an explanatory view showing an ink jet recording apparatus according to an eighth embodiment of the present invention. In this recording apparatus, one magnet 18 is provided above the carriage 3 on one end side of the movement range of the carriage 3. The rest is the same as in the sixth and seventh embodiments, and the same parts are denoted by the same reference numerals.
[0056]
In this apparatus, when the carriage 3 moves to the end where the magnet 18 is provided, the magnetic member 23 in the ink chamber 17 is attracted by the magnet 18 and moves upward, and the carriage 3 moves to another position. Then, the magnetic member 23 that has moved upward sinks under its own weight. In this way, the ink in the ink chamber 17 can be agitated by repeatedly moving the magnetic member 23 upward. Other than that, it is the same as that of each said embodiment, and there exists the same effect.
[0057]
In each of the above embodiments, the ejection element that ejects ink from the recording head 1 may be a piezoelectric vibrator that raises or lowers the pressure in the pressure generation chamber to eject the ink in the pressure generation chamber, or heats the ink in the pressure chamber. Various elements such as a heating element to be vaporized can be used.
[0058]
【The invention's effect】
As described above, according to the ink jet recording apparatus of the present invention, since the ink stirring means is provided on the apparatus side instead of the ink cartridge, the ink stored in the replaceable ink cartridge is stirred to effect sedimentation. Can be prevented.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an ink jet recording apparatus to which the present invention is applied.
FIG. 2 is a cross-sectional view showing a first embodiment of an ink jet recording apparatus of the present invention.
FIG. 3 is a plan view showing a second embodiment of the ink jet recording apparatus of the present invention.
FIG. 4 is an explanatory diagram showing the operation of the ink jet recording apparatus.
FIG. 5 is an explanatory view showing a third embodiment of the ink jet recording apparatus of the present invention.
FIG. 6 is an explanatory view showing a fourth embodiment of the ink jet recording apparatus of the present invention.
FIG. 7 is an explanatory view showing a fifth embodiment of the ink jet recording apparatus of the present invention.
FIG. 8 is a front view showing a sixth embodiment of the ink jet recording apparatus of the present invention.
FIG. 9 is an explanatory diagram showing the operation of the ink jet recording apparatus.
FIG. 10 is an explanatory view showing a seventh embodiment of the ink jet recording apparatus of the present invention.
FIG. 11 is an explanatory view showing an eighth embodiment of the ink jet recording apparatus of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Recording head 2 Ink cartridge 3 Carriage 4 Timing belt 5 Stepping motor 6 Guide bar 7 Recording paper 8 Cap 9 Wiper member 10 Guide hole 11 Locking member 12 Locking member 13 Ink supply part 14 Ink supply needle 15 Heater 16 Magnet 16A Magnet 16B Magnet 16C Electromagnet 16D Electromagnet 17 Ink chamber 18 Magnet 19 Paper feed roll 20 Magnetic particle 21 Charged particle 22 Charged body 23 Magnetic member 24 Positioning member 25 Locking portion 26 Locking portion 27 Power supply device 28 Polarity reversing means

Claims (3)

A recording head that ejects ink droplets in response to a print signal; an ink cartridge that is detachably mounted on the recording head and stores ink supplied to the recording head; and an ink cartridge mounted on the recording head. An ink jet recording apparatus comprising an ink stirring means for stirring ink,
The ink jet recording apparatus includes a carriage that reciprocally moves a recording head, and the ink agitating unit is provided at any location in a region including the magnetic member that is present in the ink chamber of the ink cartridge and the carriage moving range. An ink jet recording apparatus comprising: a magnetic member moving unit that moves the magnetic member provided in a vertical direction.   2. An ink jet recording apparatus according to claim 1, wherein said magnetic member moving means is a magnet provided such that its height changes with respect to the moving direction of the carriage.   2. An ink jet recording apparatus according to claim 1, wherein said magnetic member moving means is at least one magnet provided in an area including a moving range of the carriage.

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