The present disclosure relates to a recording apparatus and a recording method.
Japanese Patent Laid-Open No. 2015-147423 discloses a configuration of an ink-jet recording apparatus in which ink is supplied from an ink tank to a recording head through a tube using a water head difference.
Such an ink-jet recording apparatus prevents ink from dripping off by maintaining negative pressure in the recording head using the water head difference to keep a meniscus using surface tension generated in the nozzle of the recording head. The pressure in the recording head is decreased as the ink in the recording head is ejected, thereby charging the ink into the recording head from the ink tank through the tube.
The ink in the tube is acted upon by an inertia force due to acceleration/deceleration when the recording head moves back and forth. In recording an image that requires less ink ejected from the recording head, the pressure in the recording head is not decreased so much by the ejection of the ink. This causes the pressure in the recording head to be gradually increased because of an inertia force due to the movement of the recording head. The increase in the pressure in the recording head may break the meniscus of the ink formed in the nozzle to expand the ink over the nozzle surface, causing an ejection failure.
The present disclosure prevents the occurrence of ejection failure due to the break of the meniscus in the nozzle of a recording head even in recording an image that needs less ink to be ejected.
According to an aspect of the present disclosure, a recording apparatus includes an ink tank configured to store ink, a recording head including a nozzle configured to eject the ink, a carriage having the recording head mounted on the carriage and configured to move back and forth in predetermined directions to perform recording on a recording medium, a carriage control unit configured to move the carriage, and a supply tube connected to the recording head and the ink tank and configured to supply the ink from the ink tank into the recording head, wherein the supply tube includes a bent portion configured to move with movement of the carriage in the predetermined directions, wherein, assuming that, of an acceleration/deceleration area of a carriage moving area in which the carriage is accelerated or decelerated to change speed of the carriage, an area in which pressure changes to decrease negative pressure in the recording head is a first area, and an area in which the pressure changes to increase the negative pressure in the recording head is a second area, the carriage control unit moves the carriage in such a manner that an absolute value of acceleration of the carriage that is accelerated or decelerated in the first area is less than an absolute value of acceleration of the carriage that is accelerated or decelerated in the second area.
Further features of the present disclosure will become apparent from the following description of exemplary embodiments with reference to the attached drawings.
Mechanical Configuration of Ink-Jet Recording Apparatus
Overview of the Apparatus
Referring to
Ink is ejected from the ink ejection port (nozzle of nozzle arrays 101 to 108 in
The recording head 3 is fitted with a flexible wiring board for supplying a signal pulse for driving ejection, a head-temperature regulating signal, and so on. The other end of the flexible wiring board connects to a control unit including one or more control circuits (e.g., recording-head control circuit 411 in
Configuration of Recording Head
The recording head 3 is capable of ejecting different tones (including colors and tints) of ink in the main scanning direction S. In this embodiment, the recording head 3 can eject black (Bk), gray (Gy), light gray (Lgy), light cyan (Lc), cyan (C), light magenta (Lm), magenta (M), and yellow (Y) inks. A plurality of recording elements corresponding to the individual inks arranged in the X-direction and nozzle arrays 101 to 108 corresponding to the individual recording elements are juxtaposed in the Y-direction on two ejecting element substrates 100. The individual recording element arrays connect to the ink supply tubes 4 at connections 25. The inks are supplied from the ink supply system 8 through the connections 25 to the individual recording element arrays through ink channels in the recording head 3. Each supplied ink forms a meniscus on the surface of each nozzle because of surface tension. The inks do not go out of the recording head 3 unless a pressure change exceeding the withstand pressure of the meniscus occurs. While this embodiment takes the recording head capable of ejecting eight colors of ink as an example, there is no limitation to the colors and the number of colors of the inks in the recording head. Specifically, a recording head that ejects a single black (Bk) ink or a recording head that ejects four-color inks, such as black (Bk), cyan (C), magenta (M), yellow (Y) inks, may be used.
Block Diagram
An interface (I/F) circuit 410 connects the ink-jet recording apparatus 1 to an external network, such as a local area network (LAN). The ink-jet recording apparatus 1 transmits and receives various jobs and data to and from an external device, such as a host computer, via the I/F circuit 410.
An input/output unit 406 includes an input section and an output section. The input section receives an instruction to turn on the power, an instruction to execute recording, and instructions to set various functions from the user. The output section displays various items of apparatus information, such as a power-saving mode, and setting screens for various functions that can be executed by the ink-jet recording apparatus 1. In this embodiment, the input/output unit 406 is an operation panel provided on the ink-jet recording apparatus 1. The input/output unit 406 is connected to a system bus 416 via the input/output control circuit 405 so as to be capable of transmission and reception of data. In this embodiment, the CPU 401 controls information notification of the output section.
The input section may be the keyboard of the external host computer so that user's instructions can be received from the external host computer. The output section may be a light-emitting diode (LED) display, a liquid crystal display (LCD), or a display connected to the host device. If the input/output unit 406 is a touch panel, user's instructions can be received with a software keyboard. The input/output unit 406 may be a speaker and a microphone to output notification to the user by voice and input user's instruction by voice.
Alternatively, an external information processing apparatus including a CPU and a ROM that have the same functions as those of the CPU 401 and the ROM 402 and connected to the ink-jet recording apparatus 1 may perform a recording-medium determination process (described later) to determine recording media to be used in the ink-jet recording apparatus 1.
A recording-head control circuit 411 supplies a drive signal according to the record data to a nozzle driving circuit mounted on each recording head 3 and including a selector and a switch to control the recording operation of the recording head 3, such as nozzle drive sequence. For example, when print data is sent from the outside to the I/F circuit 410, the print data is temporarily stored in the RAM 403. The recording-head control circuit 411 drives the recording head 3 on the basis of record data for recording converted from the print data. At that time, a conveying-motor driving circuit 412 drives a conveying motor 413 on the basis of, for example, the band width of the record data to rotate the conveying roller 26 connected to the conveying motor 413, thereby conveying the recording media. A carriage-motor (CR) driving circuit 414 drives a CR motor 415 to move the carriage 2 along the guide rails 5 with a carriage belt 6.
The data sent from the I/F circuit 410 includes not only the print data but also data with content that is set by the printer driver. The print data may be received from the outside via the I/F circuit 410 and stored in a storage or may be stored in a storage, such as a hard disk, in advance. The CPU 401 reads the print data from the storage and converts the print data to record data for using the recording head 3 by controlling an image processing circuit 409 (binarizing process). The image processing circuit 409 executes, in addition to the binarizing process, color space conversion, HV conversion, gamma correction, image rotation, and other various image processing operations.
The CPU 401 calculates the average duty cycle of ink per band on the basis of the record data. In this embodiment, the CPU 401 counts a cycle in which two dots of ink are ejected to a 1/600 inch (600 dpi) square as 100% duty cycle. The calculated average duty cycle is temporarily stored in the RAM 403. The average duty cycle is obtained from the RAM 403 in determining the velocity of the carriage 2, and is used to determine the velocity of the carriage 2.
Configuration of Ink Supply System
Ink Supply System
In
The main tank 9 illustrated in
The main tank 9 discussed herein may be of a detachable cartridge type or in the form of injecting ink from a bottle into the main tank 9.
Variations in Pressure
As described above, the supply tube 4 connected to the subtank 10 has the extending portion 41 parallel to the Y-direction in which the carriage 2 moves and the bent portion 42 at which the supply tube 4 is folded so as to be connected to the −Y side (the left in
Parameters of Pressure Variations
Variations in the internal pressure of the recording head 3 are determined from the length L between the supply tube 4 and the connection 25 with the recording head 3 and the acceleration or deceleration.
The relationship with deceleration was measured in the same way.
Next, pressure variations were measured when acceleration and deceleration are repeated, although intermittently.
Changes in Variation Reference
To describe decompression due to variations in pressure caused by continuous reciprocating motion and ink ejection, the pressure measuring device 19 was disposed immediately in front of the recording head 3 in the recording apparatus 1 shown in
The reason why the reference value (b-0) shifts to the positive pressure side will be described with reference to
Controlling Acceleration/Deceleration
In the recording apparatus 1 of this embodiment, the acceleration/deceleration area of the carriage 2 is at both right and left ends in the reciprocating scanning operation, as shown in
The first area 51 and the second area 52 will be described hereinbelow.
First Area
The first area 51 in this specification will be described with reference to
Second Area
The second area 52 in this specification will be described with reference to
The above relationship depends on how the supply tube 4 creeps. Referring to
The first and second areas depend on, not the positional relationship in the recording apparatus 1, but an increase and decrease in the internal pressure of the recording head 3.
This embodiment will be described in more detail with reference to examples and comparative examples. The present disclosure is not limited to the following examples unless departing from the spirit of the present disclosure. For example, even if the size of the apparatus, the colors and the number of inks, the length and the diameter of the tube, the carriage velocity, or the nozzle diameter of the recording head is changed, the advantageous effects of the present disclosure are given.
In this example, the ink-jet recording apparatus 1 illustrated in
Average Duty Cycle Per One Band
The print patterns in the examples and comparative examples of the present disclosure were set at an average duty cycle per band. The discharge rate per dot of the recording head 3 used in this example was about 11.4 ng. For the definition of the average duty cycle, application of two dots of ink to a 1/600 inch (600 dpi) square was defined as 100% duty cycle. Accordingly, if the average duty cycle per band is 100%, the application amount is 22.8 ng/600 dpi. In this example, the average duty cycle per band for black (Bk) was set to 5% (the application amount in this case can be converted to 1.1 ng/600 dpi), and for the other colors, the average duty cycle per band was set to 0%.
First Area and Second Area
In the embodiments and comparative examples below, the first area 51 is the acceleration/deceleration area shown in
Evaluating Image
If the meniscus is broken, the ink expands over the nozzle surface of the recording head 3 to cause the ejection ink to be drawn by the ink expanding over the nozzle surface, causing wet misfiring.
For evaluation of the effects of the embodiments and the comparative examples, it was visually determined whether print streaks were generated on the image when image data was continuously printed on five sheets of A1-size plane paper. A solid image as shown in
In Example 1, the absolute value of acceleration at acceleration in the first area 51 was set significantly less than the absolute value of acceleration at acceleration and the absolute value of acceleration at deceleration in the second area 52. This allows the increase in the reference line of pressure variations to be kept low at about 25 mmAq, causing no print streaks due to misfiring. Thus, the print result was “misfiring not occurred”. Thus, it was determined that deterioration of images can be prevented as compared with Comparative Example 1 in which all of the acceleration/deceleration was 20.0 m/s/s, and the increase in the reference line of pressure variations was about 75 mmAq, so that misfiring occurred.
In Example 2, the absolute value of acceleration at deceleration in the first area 51 was set to 1.0 m/s/s, and the absolute value of acceleration at acceleration was set to 20.0 m/s/s. This also caused no print streaks, having the same advantageous effects as those of Example 1.
In Example 3, the absolute value of acceleration at acceleration in the first area 51 was set to 1.0 m/s/s, which is less than the absolute value 20.0 m/s/s of acceleration at acceleration and deceleration in the second area 52. The absolute value of acceleration at deceleration in the first area 51 was set to 22.0 m/s/s greater than 20.0 m/s/s. The result of printing was “Misfiring not occurred”. The reference line of pressure variations was 40 mmAq, which is slightly greater than those of Example 1 and Example 2. However, no print streaks occurred, in other words, the deterioration of image quality could be prevented, as compared with Comparative Example 1.
In Example 4, the absolute value of acceleration at acceleration in the first area 51 was set to 20.0 m/s/s, and the absolute value of acceleration at deceleration in the first area 51 was set to 1.0 m/s/s. In contrast, the absolute value of acceleration at acceleration in the second area 52 was set to 18 m/s/s, and the absolute value of acceleration at deceleration in the second area 52 was set to 20.0 m/s/s. In other words, the absolute value of acceleration at acceleration in the first area 51 was set greater than the absolute value of acceleration at acceleration in the second area 52, and the absolute value of acceleration at acceleration and the absolute value of acceleration at deceleration in the second area 52 were set greater than the absolute value of acceleration at deceleration in the first area 51. The result of printing was “Misfiring not occurred”, and the reference value of pressure variations was 30 mmAq, which is slightly greater than those of Example 1 and Example 2. This may be caused by the decrease in inertia force that decreases the pressure in the recording head 3 due to the decrease in the absolute value of acceleration at deceleration in the second area 52.
The results in Example 3 and Example 4 show that it is effective when at least one of the absolute value of acceleration at acceleration and the absolute value of acceleration at deceleration in the first area 51 is less than the absolute value of acceleration at acceleration or deceleration in the second area 52.
In Example 5, the absolute values of acceleration at acceleration and deceleration in the first area 51 were set to 3.0 m/s/s, which is less than the absolute value 20.0 m/s/s of acceleration at acceleration and deceleration in the second area 52. The printing duty cycle was set to 3% which is lower than those of Examples 1 to 4. Under the above conditions, the reference line of pressure variations during printing was about 0 mmAq without variations. As a result, no misfiring occurred, providing a high-quality image. This showed greater effects than those of Examples 1 to 4 in terms of pressure variations, allowing coping with the low duty cycle.
In Example 6, the difference between the absolute values of acceleration/deceleration in the first area 51 and the absolute values of acceleration/deceleration in the second area 52 was set smaller than that in Example 5. Specifically, the absolute values of acceleration/deceleration in the first area 51 were set to 5.0 m/s/s, and the absolute values of acceleration/deceleration in the second area 52 were set to 13.0 m/s/s. As a result, the reference line of pressure variations was increased by about 15 mmAq from that of Example 5, but no misfiring occurred, providing a high-quality image.
In Example 7, a recording head 3 including the damper shown in
In this example, the acceleration/deceleration is decreased to the minimum required for the average duty cycle of image data. In addition, for an image partly including a low duty cycle portion, the absolute values of acceleration/deceleration in the first area 51 are decreased only for a band corresponding to that portion, and in the viewpoint of throughput, acceleration/deceleration is not limited for the entire A1-size paper. Accordingly, in Example 8, the recording head 3 without the damper, used in Examples 1 to 6, was used, and a table in which acceleration/deceleration for each band corresponding to the average duty cycle of the band is set was prepared in the ROM 402 of the recording apparatus 1. In Table 1, the individual bands are numbered for description. The first band at which printing is started is numbered 1, and an image corresponding to 78 bands was input in total. The average duty cycle of the image pattern was decreased every 13 bands. The bands whose average duty cycle per band is 88% and 50% eject a large amount of ink, which may reduce a sufficient pressure in the recording head 3, so that the absolute value of acceleration/deceleration is not decreased. In other words, when the average duty cycle is half or higher (50% or higher) the maximum value (100%), the absolute value of acceleration/deceleration is nor decreased. In addition, for the bands of No. 66 to 78 in which no print data is present in one band, the absolute value of acceleration/deceleration is not decreased. This is because no ink is ejected, which does not trigger a meniscus break, reducing the tendency to break the meniscus even if the pressure in the recording head 3 is high to some degree. For the bands of Nos. 27 to 65, the absolute values of acceleration at acceleration/deceleration in the first area 51 were set less than the absolute value 20.0 m/s/s of the acceleration at acceleration/deceleration in the second area 52 according to the respective average duty cycles per band by multiplying proportions set according to the duty cycles per band. For example, for the band of Nos. 27 to 39, the absolute value was set to 20.0×0.93=18.6 m/s/s. As a result, no print streaks occurred in all the bands, providing a high-quality image. In addition, the reference line of pressure variations increased by about 30 mmAq at the maximum, which is an increase that can be withstood by the recording head 3 without a damper. The throughput can be made almost equal to that of Comparative Example 2 in which all of accelerations/decelerations are 20.0 mm/s/s because of a minimum required decrease in acceleration/deceleration, allowing outputting a high-quality image at high speed.
In Example 9, image data is input also for colors other than black (Bk). Image data that uses cyan (C), magenta (M), and yellow (Y) in addition to black (Bk), as shown in Table 2, was prepared. Table 2 shows an extract of image data of one band in A1-size image data and the ratio of acceleration/deceleration corresponding to the image data. Comparison among the average duty cycles of the individual colors in one band showed that the color with the highest average duty cycle was cyan (C) at 20%. In contrast, the color with the lowest average duty cycle was yellow (Y) at 0%. The higher the average printing duty cycle per band, the more the pressure in the recording head 3 decreased in pressure, which is advantageous against misfiring, as described in this specification. Accordingly, the most disadvantageous color against misfiring among the colors in Table 2 is yellow (Y) whose average duty cycle per band is 0%. However, if no ink is ejected at all, there is no cause to break the meniscus, allowing withstanding a certain amount of high pressure, as described in Example 8. Thus, the color that is most disadvantageous against misfiring in Table 2 is magenta (M) whose the average duty cycle is 3%. This example employed the ratio of acceleration/deceleration corresponding to magenta (M) with the lowest average duty cycle 3% among the ejected colors and set the absolute value of acceleration at acceleration and deceleration in the first area 51 to 0.62 times the absolute value of acceleration at acceleration and deceleration in the second area 52. As a result, no misfiring occurred in all the colors, providing a high-quality image without print streaks.
The result of Comparative Example 5 in which the ratio of black (Bk) whose average duty cycle per band is 10% is employed is also listed in Table 4. As a result, no print streaks occurred in black (Bk), cyan (C), and yellow (Y), but misfiring occurred and print streaks appeared in magenta (M).
Example 10 uses a recording apparatus 1 including a thermometer capable of measuring the temperature in the recording apparatus 1. The printing environmental temperature was increased to 40° ° C. from 25° ° C. in Examples 1 to 9, and the same examination was performed. Ink temperature changes according to the printing environmental temperature. The viscosity decreases as the ink temperature increases, which makes it easier for the ink in the supply tube 4 to move with an equivalent inertia force. In this example, the viscosity 3.5 mPa's of black (Bk) at 25° C. changed to 2.4 mP·s when heated to 40° C. To prevent the reference value of pressure variations from increasing, Table 3 for the printing environmental temperature was prepared on the basis of the above measurement results and was recorded in the ROM 402 of the recording apparatus 1. The printing environmental temperature was measured using a temperature and humidity sensor 23 provided in the recording apparatus 1, as shown in
In Examples 11 to 13, the length L from the bent portion of the supply tube 4 to the connection 25 with the recording head 3 was taken into account in setting the acceleration/deceleration. As shown in
In this example, the length L is the length from the bent portion 42 to the connection 25 with the recording head 3 when the carriage velocities in the first area and the second area are 0, that is, the recording head 3 is located at the opposite end extremities of the recording apparatus 1. Specifically, as shown in
In this example, the length L1 was 300 mm, and the length L2 was 50 mm. Thus, when the absolute value of acceleration at acceleration and deceleration in the second area was set to 20.0 m/s/s, the absolute value of acceleration at acceleration and deceleration in the first area was 3.3 m/s/s. When printing is started with this setting value of acceleration/deceleration, the reference value of pressure variations was about 0 mmAq, and the result of printing was “misfiring not occurred”, which showed that it was effective. The throughput was 105 seconds.
In this example, the length L from the bent portion 42 of the supply tube 4 to the connection 25 with the recording head 3 was set to the length at the trailing end of the acceleration area and the leading end of the deceleration area. In other words, the length L is the length in a state in which the acceleration or deceleration in the acceleration/deceleration areas is 0 m/s/s, and the carriage 2 is moving. In this example, the length in the first area is denoted as L1′, and the length in the second area is denoted as L2′.
The absolute value dv1/dt of acceleration at acceleration and deceleration in the first area was expressed as Eq. 4 using the determined L1′ and L2′.
In this example, the length L1′ was 82 mm, and the length L2′ was 268 mm. Accordingly, the absolute value of acceleration at acceleration and deceleration in the first area was set to 6.1 m/s/s, which is about 0.3 times 20.0 m/s/s which is the absolute value of acceleration at acceleration and deceleration in the second area from the relationship of Eq. 4. When printing is started with the above setting, no print streaks occurred, as in Example 11, and the throughput was faster, 99 seconds. However, the absolute value of acceleration at acceleration and deceleration in the first area was greater than the absolute value of acceleration at acceleration and deceleration in the second area, as compared with Example 11. For this reason, the reference value of pressure variations increased slightly to 25 mmAq although no misfiring occurred.
In this example, a length L from a bent portion to the connection 25 with the recording head 3 was determined in consideration of the ink flowing direction. In this example, as shown in
In this case, the direction of the inertia force acting on the ink in the supply tube 4 from the bent portion 110 to the bent portion 120 in the first area is opposite to the direction of the inertia force acting on the ink in the supply tube 4 from the bent portion 120 to the connection 25 with the recording head 3.
Accordingly, for the pressure in the recording head 3, the inertia force acting on the ink in the supply tube 4 between the bent portion 110 and the bent portion 120 acts toward the positive pressure side. The inertia force acting on the ink in the supply tube 4 from the bent portion 120 to the connection 25 with the recording head 3 acts toward the negative pressure side. In the second area, an opposite force acts similarly. Accordingly, for pressure variations, the length L10 of the supply tube 4 between the bent portion 110 and the bent portion 120 minus the length L11 between the bent portion 120 and the connection 25 with the recording head 3 in the first area is referred to as L1″. In this example, the lengths 10, 11, and L1″ are not actual lengths of the supply tube 4 but the lengths projected in the moving direction of the carriage 2. Likewise, the length L2″ is the length L20 of the supply tube 4 between the bent portion 130 and the bent portion 140 projected in the moving direction of the carriage 2 minus the length L21 of the supply tube 4 between the bent portion 140 and the connection 25 with the recording head 3 projected in the moving direction of the carriage 2. Thus, the absolute value dv1/dt of acceleration at acceleration and deceleration in the first area of this example was set to 4.0 m/s/s determined from Eq. 5.
During printing, the reference value of pressure variations shifted about 5 mmAq to the positive pressure side, but no print streaks occurred, and it was determined that no misfiring occurred. The throughput was 103 seconds. Thus, also the supply tube 4 having two or more bent portions as in this example prevents deterioration of image quality by controlling the acceleration/deceleration.
In Comparative Example 1, all of the absolute values of acceleration at acceleration and deceleration in the first area and the second area were set to 20.0 m/s/s, as shown in Table 4. The examination showed that the reference value of pressure variations increased by about 75 mmAq, causing print streaks.
Next, in Comparative Example 2, the average duty cycle per band was set to 80% only for black (Bk) image data under the same conditions as in Comparative Example 1. The result of printing was “misfiring not occurred”. This is because the reference value of pressure variations did not change because the pressure in the recording head is decreased by ejecting ink. A low printing duty cycle as in Comparative Example 1 causes print streaks.
In Comparative Example 3, all of the absolute values of acceleration/deceleration were set to 30 m/s/s. In addition, the recording head includes a damper for absorbing dynamic pressure as shown in
In Comparative Example 4, the absolute value of acceleration at acceleration and deceleration in the first area was set to 13.0 m/s/s, and the absolute value of acceleration at acceleration and deceleration in the second area was set to 10.0 m/s/s. Although the acceleration/deceleration were decreased as a whole, the absolute value of acceleration/deceleration in the first area was greater than the absolute value of acceleration/deceleration in the second area. As a result, the reference value of pressure variations in the recording head increased significantly, causing misfiring. This shows that the relative relationship between the acceleration/deceleration in the first area and the acceleration/deceleration in the second area has an effect.
In Comparative Example 5, the image data used in Example 9 was input, and the acceleration and the deceleration in the first area were set to 18.0 m/s/s suited to the average duty cycle per band of black (Bk). As a result, for black (Bk), the average duty cycle was high, forming a high-quality image, but for magenta (M) with the low average duty cycle, print streaks due to misfiring occurred.
The table below is a list of the examination conditions of Examples 1 to 13 and Comparative Examples 1 to 5.
The apparatus configurations described above are mere examples of an apparatus configuration for realizing the present disclosure. It is needless to say that, even if the size of the recording apparatus, the number of print inks, the number of supply tubes, the number of ejecting element substrates, and so on differ, the present disclosure is applicable. Although the examples illustrate a configuration in which the carriage velocity is controlled using, not the average duty cycle, the average duty cycle, the carriage velocity may be determined using the total dot count per band, the total amount of ink ejected, or the like.
The embodiments prevent ejection failure due to the breakage of the meniscus.
While the present disclosure has been described with reference to exemplary embodiments, it is to be understood that the disclosure 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. 2021-106633 filed Jun. 28, 2021, which is hereby incorporated by reference herein in its entirety.
Number | Date | Country | Kind |
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2021-106633 | Jun 2021 | JP | national |
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20070139487 | Sekiguchi | Jun 2007 | A1 |
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Number | Date | Country |
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2015147423 | Aug 2015 | JP |
Number | Date | Country | |
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20230001718 A1 | Jan 2023 | US |