Patent Grant
11086259
The present invention relates to an image forming apparatus to which a toner container is attachable.
Conventionally, image forming apparatuses of an electrophotographic type, an electrostatic recording type, and so forth, to which a toner container storing toner is attachable, include a known one that replenishes toner in the toner container to a developing device via a container (referred to as the hopper). The known image forming apparatus supplies, when toner in the hopper becomes insufficient, toner to the hopper by rotating the attached toner container. This causes toner to be stored in the hopper, which is used for development by the developing device. At this time, whether or not the toner container is rotating is monitored by a rotation sensor. If rotation of the toner container is not detected, an abnormality message is displayed on a screen. However, there are various kinds of causes why rotation of the toner container is not detected, and hence it takes a time to identify the cause.
Assuming that it is assured that a power supply circuit board and a motor are normally operating, it is possible to consider, as the main cause of disabling the rotation sensor from detecting rotation of the toner container, failure of the rotation sensor itself and rotation failure of the toner container e.g. due to faulty attachment of the toner container. For example, in the case of faulty attachment of the toner container, load on a gear increases, which causes improper rotation of the toner container or disables the toner container from rotating. In recent years, the number of units, as components associated with the developing device, has been increased, and hence if it is possible to quickly and accurately identify a unit to be replaced according to the cause of a failure, this leads to reduction of downtime.
An image forming apparatus disclosed in Japanese Laid-Open Patent Publication (Kokai) No. 2009-151180 includes a current detecting circuit provided in a bottle motor that rotates a toner container, and determines whether or not an overload (heavy load) of the toner container has occurred, based on a value of electric current flowing through the bottle motor. In the disclosed image forming apparatus, in a case where it is determined that an overload has occurred, it is determined that faulty attachment of the toner bottle has occurred, and the downtime is reduced by prompting a user to reattach the toner bottle.
However, in the disclosed image forming apparatus, it is necessary to provide the exclusive current detection circuit in the bottle motor, and hence the configuration becomes complicated and further it is disadvantageous from the viewpoint of cost.
The present invention provides an image forming apparatus capable of determining which of failure of a detection unit for detecting rotation of a toner container and rotation failure of the toner container has occurred, without providing a component for detecting a drive load.
The present invention provides an image forming apparatus comprising a photosensitive member, an exposure unit configured to expose the photosensitive member to form an electrostatic latent image, a developing unit configured to develop the electrostatic latent image formed on the photosensitive member with toner, an attachment section to which a toner container that stores toner is attachable, a drive unit configured to drive the toner container attached to the attachment section, for rotation, to discharge toner from the toner container, a storage section configured to store the toner discharged from the toner container attached to the attachment section, a replenishment unit configured to replenish the toner stored in the storage section to the developing unit, a first detection unit configured to detect rotation of the toner container attached to the attachment section, a second detection unit configured to detect the toner stored in the storage section, and a determination unit configured to determine, based on a detection result of the first detection unit and a detection result of the second detection unit, which of failure of the first detection unit and rotation failure of the toner container has occurred.
According to the present invention, it is possible to determine which of failure of the detection unit for detecting rotation of the toner container and rotation failure of the toner container has occurred, without providing a component for detecting a drive load.
Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings).
The present invention will now be described in detail below with reference to the accompanying drawings showing embodiments thereof.
In the printer unit 101, recording sheets P, stored in a sheet feed cassette 110, are fed to a conveying path by a pickup roller 111, a sheet feeding roller 112, and a retard roller 113, one by one. Each recording sheet P fed from the sheet feed cassette 110 is conveyed along the conveying path by a sheet feeder conveying roller 114. When the recording sheet P has reached a position of a registration roller pair 115, skew of the sheet P is corrected by the registration roller pair 115 at rest. After that, the registration roller pair 115 starts to rotate to thereby convey the recording sheet P to a transfer nip between a photosensitive drum (photosensitive member) 131 and a transfer roller 133.
The printer unit 101 has an image forming section that forms an image on a recording sheet P, and the image forming section is comprised of a laser scanner unit 120, the photosensitive drum 131, a charge roller 132, the transfer roller 133, and a developing device 140. In the image forming section, an outer peripheral surface of the photosensitive drum 131, which is driven for rotation, is uniformly charged to a potential of a predetermined polarity by action of the charge roller 132. The laser scanner unit 120 is an exposure unit configured to expose the charged photosensitive drum 131 with a light beam (laser light). More specifically, the laser scanner unit 120 outputs laser light L modulated according to image information (time-series digital pixel signal), and scans the charged photosensitive drum 131 with the laser light L to thereby form an electrostatic latent image on the photosensitive drum 131. The laser scanner unit 120 outputs the laser light L based on image data (image information) obtained by the reader unit 102 that reads an image of an original, or based on image data received from an external apparatus, such as a personal computer, via a network.
The developing device 140 includes a developing roller 141 and develops an electrostatic latent image on the photosensitive drum 131 with toner supplied (replenished) from a toner replenishment unit 150 which includes a toner bottle T, to thereby form a toner image. To form the toner image, toner corresponding to the image data is discharged from the developing device 140. The toner image formed on the photosensitive drum 131 is moved to the transfer nip in accordance with rotation of the photosensitive drum 131. A transfer bias of a polarity opposite to the polarity of the photosensitive drum 131 is applied to the transfer roller 133, whereby the toner image on the photosensitive drum 131 is transferred onto a surface of the recording sheet P at the transfer nip.
The recording sheet P having the toner image transferred thereon in the image forming section is conveyed into a fixing device 160. The fixing device 160 applies heat and pressure to the recording sheet P using a fixing heater and a pressure roller to thereby fix the toner image on the recording sheet P. The recording sheet P on which the image has been thus formed is discharged, after passing the fixing device 160, onto a discharge tray 171 outside the apparatus by a discharge roller 170.
Further, in a case where double-sided printing is performed on the recording sheet P, the recording sheet P on a first side of which image formation has been finished passes the position of an inversion flapper 181 and is then conveyed in an opposite direction by the discharge roller 170 and guided to an inversion conveying path 180 by the inversion flapper 181. The recording sheet P having been guided to the inversion conveying path 180 is conveyed to the position of the registration roller pair 115 again by inversion section conveying rollers 182 and 183. At this time, the first side and a second side of the recording sheet P are inverted from when the image forming operation was performed on the first side. Then, image formation is performed on the second side of the recording sheet P similarly to the above-mentioned image formation on the first side, and then the recording sheet P is discharged onto the discharge tray 171.
The ROM 401 stores control programs for controlling the overall operation of the image forming apparatus 100. The RAM 402 is a volatile storage device (memory) which is used as a work area for the CPU 400 and is used to temporarily store various data, such as image data. The CPU 400 controls the overall operation of the image forming apparatus 100 by loading the control programs stored in the ROM 401 into the RAM 402, and executing the loaded programs. The CPU 400 controls the operation of the toner replenishment unit 150 by controlling the operations of a bottle motor 201 and a conveying path motor 211. In the toner replenishment unit 150, there are arranged a bottle rotation sensor 202 (first detection unit), a hopper-internal toner sensor 217 (second detection unit), a conveying path-internal rotation sensor 213, and a developing device-internal toner sensor 221. Signals output from these sensors 202, 217, 213, and 221 are input to the CPU 400.
As shown in
When the toner bottle T rotates in a clockwise direction, as viewed in
If the amount of light received by the light receiving section of the bottle rotation sensor 202 is smaller than the threshold value, the CPU 400 recognizes that the bottle rotation sensor 202 outputs a low-level signal (see
The hopper-internal toner sensor 217 for detecting presence/absence of toner in the hopper 216 is provided in the hopper 216. The CPU 400 controls the toner bottle T so as to cause toner to be stored in the hopper 216 up to a boundary face at which the hopper-internal toner sensor 217 is disposed. Details of a method of detecting presence/absence of toner using the hopper-internal toner sensor 217 will be described hereinafter with reference to
A rotational shaft of the screw 212 within the toner conveying path 210 is connected to the conveying path motor 211 via a drive gear train (not shown). A rotational drive force is applied from the conveying path motor 211 to the screw 212 via the drive gear train. The screw 212 conveys toner flowing into the toner conveying path 210 in one direction (from left to right, as viewed in
The hopper-internal toner sensor 217 and the developing device-internal toner sensor 221 are both magnetic permeability sensors.
Further, the CPU 400 uses different control parameters based on sensor output values in a manner adapted to respective usages of the toner sensors 217 and 221. For example, it is necessary to keep the toner density in the developing device 140 constant, and hence the CPU 400 directly uses the sensor output value of the developing device-internal toner sensor 221 as a control parameter. On the other hand, to store a first predetermined amount of toner in the hopper 216, it is only required to determine whether or not there is a corresponding amount of toner. To this end, the CPU 400 compares the output of the hopper-internal toner sensor 217 with a binarization threshold value, and in a case where the output value is not smaller than the binarization threshold value, the CPU 400 acquires a signal indicating that toner is present (ON) as a detection result. On the other hand, in a case where the output value of the hopper-internal toner sensor 217 is smaller than the binarization threshold value, the CPU 400 acquires a signal indicating that toner is absent (OFF) as the detection result. In other words, the output of the toner sensor 217 is changed to ON if the toner amount in the hopper 216 is not smaller than the first predetermined amount, and to OFF if the toner amount in the hopper 216 is smaller than the first predetermined amount. The first predetermined amount corresponds to the position where the toner sensor 217 is disposed (boundary face). The CPU 400 uses the detection result thus obtained by the toner sensor 217 as a control parameter.
The CPU 400 acquires information on presence or absence of toner in the hopper 216 and the toner density in the developing device 140, by monitoring the output signals from the hopper-internal toner sensor 217 and the developing device-internal toner sensor 221 e.g. at intervals of 100 msec. Note that the above-mentioned method of determining presence/absence of toner is described, by way of example, but the configuration for detecting presence/absence of toner using a piezo sensor may be employed. The hopper-internal toner sensor 217 is not necessarily required to be configured to detect presence/absence of toner in the hopper 216, but may be configured to output a value corresponding to the amount of toner.
Next, a sequence for replenishing toner from the toner bottle T to the hopper 216 and a sequence for replenishing toner from the hopper 216 to the developing device 140 will be described with reference to
When the image forming operation is being performed, toner corresponding to image data is discharged from the developing device 140. With this operation, when the toner density in the developing device 140 is lowered, toner is replenished from the hopper 216 to the developing device 140 through the toner conveying path 210 (see
Incidentally, when the amount of toner in the toner bottle T (in the toner container) becomes smaller than a second predetermined amount, even when the toner bottle T is rotated, toner is no longer replenished to the hopper 216. Therefore, as shown in
Here, there is a case where the toner bottle T is disabled from properly rotating (hereinafter referred to as the rotation failure) due to excessive rotation load (too heavy rotation load) of the toner bottle T caused e.g. by faulty attachment of the toner bottle T to the attachment section 220. In this case, when the CPU 400 as a determination unit determines that the toner bottle T is not rotating, the CPU 400 executes an abnormality diagnosis sequence (an abnormality determination process, described hereinafter with reference to
Next, a method of identifying, in a case where the detection result of the bottle rotation sensor 202 indicates that the toner bottle T is not rotating, whether a non-rotating state of the toner bottle T is caused by failure (abnormality) of the bottle rotation sensor 202 or rotation failure of the toner bottle T will be described with reference to
During normal toner replenishment, as shown in
In a case where the bottle rotation sensor 202 is in failure, as shown in
During rotation failure of the toner bottle T, as shown in
Next, the abnormality diagnosis sequence will be described. Conventionally, when the non-rotating state of the toner bottle T is detected by the bottle rotation sensor 202, it has been impossible to identify which unit has made it impossible to detect rotation of the toner bottle T. This is because whether or not the toner bottle T is rotating has been determined only depending on the bottle rotation sensor 202. In contrast, in the present embodiment, the CPU 400 determines which of failure of the bottle rotation sensor 202 and rotation failure of the toner bottle T has occurred, by making use the output of the hopper-internal toner sensor 217.
Here, as a premise, it is assumed that no electrical failure, such as coming-off of a connector of a power supply circuit board or bundled wires, has occurred. In a case where the detection result of the bottle rotation sensor 202 indicates that the toner bottle T is not rotating, the CPU 400 stores the output of the hopper-internal toner sensor 217, obtained at this time, in the RAM 402 as a stored value Pr. For example, although in the illustrated example in
However, there is a possibility that the bottle rotation sensor 202 fails in a state in which the toner bottle T is almost out of toner, and hence this situation is also taken into account when performing the determination. Even when the toner bottle T is rotating, toner ceases to be discharged midway through replenishment, and hence the stored value Pr of the hopper-internal toner sensor 217 is changed to “OFF”. In this case, if it is uniformly determined that the toner bottle T is in rotation failure, this leads to an erroneous determination.
To avoid this, in the present embodiment, the CPU 400 acquires a toner remaining amount Tr remaining in the toner bottle T at a time point when the operation has timed out in a state in which the output of the bottle rotation sensor 202 is held at OFF. Further, the CPU 400 acquires a replenishment required amount Hr (necessary replenishment amount) of toner to the hopper 216 at a time when the operation has timed out in a state in which the output of the bottle rotation sensor 202 is held at OFF. The replenishment required amount Hr is an amount of toner required to recover the output of the hopper-internal toner sensor 217 from OFF to ON. Then, in a case where the toner remaining amount Tr is smaller than the replenishment required amount Hr, the CPU 400 does not perform determination regarding which of failure of the bottle rotation sensor 202 and rotation failure of the toner bottle T has occurred. Instead, the CPU 400 performs error notification, such as display of the error on the UI 403.
The toner remaining amount Tr can be determined based on the total number of rotations Br2 of the toner bottle T, counted from the start of use of a new toner bottle T. The replenishment required amount Hr can be determined based on the number of rotations Dr of the screw 212 (see
Next, a process including the sequence for replenishing toner from the toner bottle T to the hopper 216 and an abnormality diagnosis sequence will be described with reference to
In a step S801, the CPU 400 waits until it is determined based on the output of the hopper-internal toner sensor 217 that toner is absent in the hopper 216. Then, if it is determined that toner is absent in the hopper 216 because the output of the hopper-internal toner sensor 217 is changed to OFF, the CPU 400 proceeds to a step S802.
In the step S802 and steps S803 and S804, the CPU 400 initializes a bottle toner-absent timer Tx, a bottle rotation sensor timer Ty, and a bottle motor timer Tz to 0. Here, the bottle toner-absent timer Tx is a timer for determining that the amount of toner in the toner bottle T has become smaller than the second predetermined amount (referred to as “bottle toner is absent”). The bottle rotation sensor timer Ty is a timer for determining that the ON edge of the output the bottle rotation sensor 202 is not detected. The bottle motor timer Tz is a timer for monitoring the rotation time of the bottle motor 201. The value counted up by each timer is used by converting the same to a time.
In a step S805, the CPU 400 stores a bottle rotation counter value Br1 stored in the RAM 402, in another address, as the total number of rotations Br2 of the toner bottle T. The CPU 400 can determine the toner remaining amount Tr in the toner bottle T before driving the toner bottle T for rotation, from the total number of rotations Br2 (step S1002 in
In a step S806, the CPU 400 starts to drive the bottle motor 201 for rotation. This causes the toner bottle T to be rotated. In a step S807, the CPU 400 counts up the bottle motor timer Tz using the timer 291. In a step S808, the CPU 400 determines whether or not the bottle toner-absent timer Tx has timed out. That is, the CPU 400 determines whether or not the count of the bottle toner-absent timer Tx has exceeded a time timeX (e.g. 40 sec). The time timeX is stored in advance in the RAM 402. If it is determined that the bottle toner-absent timer Tx has timed out because Tx>timeX holds, it is determined that the amount of toner in the toner bottle T has become smaller than the second predetermined amount (bottle toner is absent), and hence the CPU 400 proceeds to a step S823. On the other hand, if it is determined that the bottle toner-absent timer Tx has not timed out, the CPU 400 proceeds to a step S809. In the step S809, the CPU 400 counts up the bottle toner-absent timer Tx using the timer 291.
In a step S810, the CPU 400 determines whether or not the bottle rotation sensor timer Ty has timed out. That is, the CPU 400 determines whether or not the count of the bottle rotation sensor timer Ty has exceeded a time timeY. The time timeY is stored in advance in the RAM 402. If it is determined that the bottle rotation sensor timer Ty has timed out because Ty>timeY holds, it is determined that the time timeY has elapsed in a state in which the output of the bottle rotation sensor 202 is held at OFF. In this case, the detection result of the bottle rotation sensor 202 indicates that the toner bottle T is not rotating, and hence there is a possibility that the bottle rotation sensor 202 is in failure or the toner bottle T is in rotation failure. Accordingly, the CPU 400 proceeds to a step S820. On the other hand, if it is determined that the bottle rotation sensor timer Ty has not timed out, the CPU 400 proceeds to a step S811.
In the step S811, the CPU 400 determines whether or not an ON edge of the output of the bottle rotation sensor 202 has been detected. Then, if an ON edge of the output of the bottle rotation sensor 202 has been detected, it is possible to determine that the toner bottle T is rotating, and hence the CPU 400 clears the bottle rotation sensor timer Ty in a step S812. Then, in a step S813, the CPU 400 counts up the bottle rotation counter value Br1, and then proceeds to a step S815. On the other hand, if an ON edge of the output of the bottle rotation sensor 202 has not been detected, the CPU 400 counts up the bottle rotation sensor timer Ty in a step S814, and then proceeds to the step S815.
In the step S815, the CPU 400 determines whether or not the bottle motor timer Tz has timed out. That is, the CPU 400 determines whether or not the bottle motor timer Tz has exceeded a time timeZ (Tz>timeZ). The time timeZ is stored in advance in the RAM 402. If it is determined that the bottle motor timer Tz has not timed out, the CPU 400 returns to the step S807. On the other hand, if it is determined that the bottle motor timer Tz has timed out, the CPU 400 clears the bottle motor timer Tz in a step S816, and then proceeds to a step S817.
In the step S817, the CPU 400 stops driving the bottle motor 201. In a step S818, the CPU 400 determines, based on the output of the hopper-internal toner sensor 217, whether or not toner is present in the hopper 216. Then, if the output of the hopper-internal toner sensor 217 is held at OFF so that it is determined that toner is absent in the hopper 216, the CPU 400 returns to the step S806. On the other hand, if the output of the hopper-internal toner sensor 217 has been changed to ON so that it is determined that toner is present in the hopper 216, the CPU 400 proceeds to a step S819. In the step S819, the CPU 400 initializes the bottle toner-absent timer Tx to 0, and then returns to the step S801.
In the step S820, the CPU 400 initializes the bottle rotation sensor timer Ty to 0. In a step S821, the CPU 400 stops driving the bottle motor 201. In a step S822, the CPU 400 performs the abnormality determination process described hereinafter with reference to
In the step S823, the CPU 400 initializes the bottle toner-absent timer Tx to 0. The CPU 400 stops driving the bottle motor 201 in a step S824, and determines that toner is absent in the toner bottle T and stores this fact in the RAM 402 in a step S825, followed by terminating the process in
In a step S901, the CPU 400 initializes a rotation counter (the number of rotations Dr) of the screw 212. The screw rotation counter is used to record how many rotations the screw 212 make after the output of the hopper-internal toner sensor 217 is changed to OFF. The number of rotations Dr is used to obtain the amount of toner in the hopper 216 and further the replenishment required amount Hr.
In a step S902, the CPU 400 determines whether or not the output of the hopper-internal toner sensor 217 is ON. Then, if the output of the hopper-internal toner sensor 217 is ON, in a step S903, the CPU 400 initializes the screw rotation counter, and then proceeds to a step S904. However, if the output of the hopper-internal toner sensor 217 is OFF, the CPU 400 proceeds to the step S904 without initializing the counter.
In the step S904, the CPU 400 determines whether or not toner is being replenished from the hopper 216 to the developing device 140. This is determined, for example, based on whether or not the CPU 400 controls to drive the conveying path motor 211. Then, if toner is not being replenished from the hopper 216 to the developing device 140, the screw 212 is not rotated, and hence the CPU 400 returns to the S902. On the other hand, if toner is being replenished from the hopper 216 to the developing device 140, the CPU 400 proceeds to a step S905, wherein the CPU 400 waits until an edge of the output of the conveying path-internal rotation sensor 213 is detected. When an edge of the output of the conveying path-internal rotation sensor 213 is detected, the CPU 400 counts up the screw rotation counter (Dr←Dr+1) in a step S06. The value of the screw rotation counter is stored in the RAM 402 as the number of rotations Dr. Note that in repeating the step S905, a step for detecting an error caused by timeout may be provided, and occurrence of the error may be notified to the user.
In a step S907, the CPU 400 determines whether or not the value of the screw rotation counter (Dr) is not smaller than a threshold value. The threshold value is set to a value corresponding to the first predetermined amount of toner in the hopper 216. Then, if Dr<the threshold value holds, the CPU 400 returns to the step S902. On the other hand, if Dr≥the threshold value holds, it can be determined that all of toner in the hopper 216 has been discharged to the developing device 140, and hence the CPU 400 terminates the process in
In a step S1003, the CPU 400 calculates the replenishment required amount Hr based on the number of rotations Dr which is a value of the screw rotation counter. Assuming that an average value of the amount of toner discharged per one rotation of the screw 212 is represented by α, the replenishment required amount Hr is calculated by Hr=αDr. Note that the method of acquiring the replenishment required amount Hr is not limited to the above-mentioned example. For example, the replenishment required amount Hr may be calculated from the rotation time of the screw 212 or by the method of detecting an amount of toner actually discharged from the hopper 216. In the step S1004, the CPU 400 determines whether or not the toner remaining amount Tr is not smaller than the replenishment required amount Hr (necessary replenishment amount) of toner to the hopper 216 (Tr≥Hr). If Tr≥Hr holds, the current toner remaining amount Tr makes it possible to replenish the replenishment required amount Hr of toner to the hopper 216, and hence the CPU 400 proceeds to the step S1005. However, if Tr<Hr holds, the current toner remaining amount Tr makes it impossible to replenish the replenishment required amount Hr of toner to the hopper 216, and hence the CPU 400 proceeds to a step S1008.
In the step S1005, the CPU 400 determines whether or not the stored value Pr stored in the RAM 402 is “ON” (indicating that hopper toner is present). Then, if the stored value Pr is “ON”, in a step S1006, the CPU 400 determines that the bottle rotation sensor 202 is in failure. In this case, the CPU 400 displays a message indicating that the hopper 216 is identified as a unit corresponding to the abnormal spot, on the UI 403 (see
In the step S1008, the CPU 400 performs error display, followed by terminating the process in
Note that the manner of error notification is not limited to the error display, shown in
According to the present embodiment, the CPU 400 determines which of failure of the bottle rotation sensor 202 and rotation failure of the toner bottle T has occurred, based on the detection result of the bottle rotation sensor 202 and the detection result of the hopper-internal toner sensor 217. The CPU 400 performs determination of the cause of the abnormality according to a detection result of the bottle rotation sensor 202, which indicates that the toner bottle T is not rotating. More specifically, the CPU 400 performs determination of the cause of the abnormality based on the output of the hopper-internal toner sensor 217 (stored value Pr) stored when it is determined that the toner bottle T is not rotating (step S1005). That is, in a case where the stored value Pr indicates that the amount of toner in the hopper 216 is not smaller than the first predetermined amount, the CPU 400 determines that the bottle rotation sensor 202 is in failure. On the other hand, in a case where the stored value Pr indicates that the amount of toner in the hopper 216 is smaller than the first predetermined amount, the CPU 400 determines that rotation failure of the toner bottle T has occurred. With this, it is possible to determine which of failure of the detection unit (bottle rotation sensor 202) for detecting rotation of the toner bottle T and rotation failure of the toner bottle T has occurred without providing a component, such as a current detecting circuit, for detecting a drive load of the bottle motor 201. Therefore, labor of a service person, for identifying the cause of a failure, is reduced, which makes it possible to reduce downtime. Further, this also contributes to cost reduction.
Further, in a case where the toner remaining amount Tr is smaller than the replenishment required amount Hr, the determination regarding which of failure of the bottle rotation sensor 202 and rotation failure of the toner bottle T has occurred is not performed. With this, it is possible to prevent erroneous determination which can occur e.g. in a case where the bottle rotation sensor 202 is in failure in a state in which the toner bottle T is almost out of toner.
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. 2019-002018 filed Jan. 9, 2019, which is hereby incorporated by reference herein in its entirety.
| Number | Date | Country | Kind |
|---|---|---|---|
| JP2019-002018 | Jan 2019 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 20100247119 | Kawahara | Sep 2010 | A1 |
| 20150071659 | Iikura | Mar 2015 | A1 |
| 20180299815 | Sakaguchi | Oct 2018 | A1 |
| Number | Date | Country |
|---|---|---|
| 2009151180 | Jul 2009 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20200218188 A1 | Jul 2020 | US |
