JP2007034016A - Fixing device and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent trouble such as a fixation defect, an abnormal image, and unit damage due to erroneous detection of a contactless sensor. <P>SOLUTION: Temperature detection information on a fixing roller 1 is output from a thermopile 8 and a contact type thermistor 9 to a CPU 31. The CPU 31 compares a detected temperature of the thermopile 8 and a detected temperature of the contact type thermistor 9 with each other to monitor detection abnormality of the thermopile 8, computes the difference between the temperature detected and measured by the thermopile 8 and the temperature detected and measured by the contact type thermistor 9, and determined that the thermopile 8 is in an abnormal state when the difference exceeds a predetermined fixed value (±10°C). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fixing device that fixes an unfixed image on a transfer sheet using a heating rotator and a pressure rotator, and an image forming apparatus equipped with the fixing device.

  FIG. 17 is a schematic configuration diagram of a conventional fixing device, FIG. 18 is an explanatory view showing the relationship between the fixing roller and the temperature sensor in the fixing device of FIG. 17, and 1 is a fixing roller having a built-in heater 2 as a heating source. Reference numeral 3 denotes a pressure roller that is in pressure contact with the fixing roller 1. The surface hardness of the pressure roller 3 is about 30 Hs, and the surface hardness of the fixing roller 1 is about 40 Hs. Depends on the nip width required in the process. For example, an infrared heater such as a halogen heater is used as the heater 2 disposed in the fixing roller 1.

  Reference numerals 4 and 5 denote an inlet guide plate and an outlet guide plate for introducing and guiding the transfer paper P to the nip portion between the fixing roller 1 and the pressure roller 3, and 6 acts to peel off the transfer paper P from the fixing roller 1. It is a separation plate.

  In FIG. 17, the transfer paper P onto which an unfixed toner image has been transferred and conveyed to the entrance guide plate 4 is heated and pressed at the nip portion between the rotating fixing roller 1 and the pressure roller 3. As a result, the unfixed toner image is fixed on the transfer paper P and sent to the exit guide plate 5.

  A temperature sensor 7 is provided for detecting the surface temperature of the fixing roller 1 for heater control of the heater 2 provided on the fixing roller 1.

  Since the temperature sensor 7 is in contact with the fixing roller 1, an image formed on the transfer paper P over time due to scratches generated on the fixing roller 1 by the temperature sensor 7, or toner or paper dust accumulated in the temperature sensor 7. In the worst case, the transfer paper may be wound around the fixing roller 1 due to the fixing of the toner.

In order to eliminate such problems, a non-contact temperature sensor is used as the temperature sensor. As the non-contact type temperature sensor, a thermopile thermocouple, an NC sensor, a thermistor type, or the like is used. However, the non-contact type temperature sensor is easily affected by dirt and airflow caused by toner, paper dust, and the like, and various proposals have been made and implemented as in Patent Documents 1 and 2 in order to cope with this.
JP 2004-45330 A JP 2005-24436 A

  As described above, non-contact temperature sensors that are easily affected by dirt and airflow due to toner, paper dust, etc. can be dealt with by adding wipers, airflow adjustment, etc. As a safety measure, only a method of cutting off power supplied to a heater such as a thermostat or a thermal fuse was employed.

  However, this power cut-off method tends to lead to defective fixing and abnormal images, and in the worst case, the unit may be damaged.

  The object of the present invention is to solve the above-mentioned conventional problems, prevent the occurrence of defects such as fixing failure, abnormal image, unit damage, etc. due to erroneous detection of a non-contact sensor, and promptly detect the abnormality. An object of the present invention is to provide a fixing device and an image forming apparatus capable of grasping the situation.

  In order to achieve the object, the invention described in claim 1 includes a heating rotator provided with a heating source, and a press-contact rotator that press-contacts the heating rotator, the heating rotator and the press-contact rotator, In a fixing device for fixing an unfixed image on the transfer paper by passing the transfer paper through the nip of the printer, at least two temperature sensors for detecting the temperature of the heating rotator are provided, and at least one of the temperature sensors Is a non-contact type temperature sensor, and includes a control unit that monitors the detection temperature of the non-contact type temperature sensor based on the detection temperature of another temperature sensor and stops heating driving and rotation driving when an abnormality occurs. To do.

  According to a second aspect of the present invention, there is provided a heat-resistant endless belt stretched by at least two or more rotating bodies, and at least one pressing body that is in pressure contact with at least one of the rotating bodies across the endless belt. A fixing device for fixing an unfixed image on the transfer paper by passing the transfer paper through a nip between the endless belt and the press contact member. At least two temperature sensors for detecting the temperature of the non-contact type temperature sensor, and the temperature detected by the non-contact type temperature sensor is monitored based on the temperature detected by another temperature sensor. A control unit for stopping the heating drive and the rotation drive is provided.

  According to a third aspect of the present invention, there is provided a heat-resistant endless belt stretched by at least two or more rotating bodies, and at least one pressing body that is in pressure contact with at least one of the rotating bodies across the endless belt. A fixing device for fixing an unfixed image on the transfer paper by passing the transfer paper through a nip between the endless belt and the press contact member. A heating element is provided in the heating source, and at least two temperature sensors are provided. The temperature sensor detects the temperature of the endless belt, and at least two of the temperature sensors are used as non-contact temperature sensors. The detection temperature of the other non-contact type temperature sensor is configured to be monitored, and the temperature of each of the heating bodies is controlled based on the detection temperature of each temperature sensor, and Serial based on the monitoring the temperature detected by the non-contact type temperature sensor, characterized in that the abnormality in either one has a control unit for stopping the heating drive and the rotary drive when it is detected that occurred.

  According to the fixing device of the present invention having the above-described configuration, even when the non-contact type temperature sensor causes a false detection due to dirt or the like, it is monitored by another temperature sensor, so that an appropriate fixing operation is performed. In addition, it is possible to prevent the occurrence of fixing failure and abnormal images, and in turn to prevent damage to the unit.

  According to a fourth aspect of the present invention, in the fixing device according to any one of the first to third aspects, the temperature sensor other than the non-contact type temperature sensor is a contact type temperature sensor. Since the temperature of the heating rotator having the heating source can be reliably detected by the mold temperature sensor, the heating drive and the rotation drive can be reliably controlled against the detection abnormality of the non-contact type temperature sensor.

  According to a fifth aspect of the present invention, in the fixing device according to the fourth aspect, the contact-type temperature sensor is installed outside the sheet passing range of the transfer paper. Since temperature detection can be reliably performed without damaging the temperature detection target within the range, it is possible to cope with the detection abnormality of the non-contact temperature sensor without increasing the cost.

  According to a sixth aspect of the present invention, in the fixing device according to any one of the first to third aspects, the control unit stops all driving systems simultaneously with the heating stop of the heating source. By stopping all driving at the same time as the occurrence of an abnormality, it is possible to prevent the occurrence of problems such as transfer paper having an unfixed image jammed in the middle of the conveyance path or scattering of an unfixed image.

  According to a seventh aspect of the present invention, in the fixing device according to any one of the first to third aspects, an abnormality notification information signal is output simultaneously with the stop, and with this configuration, an abnormality is generated and stopped. This information signal can be output, so that the down time of the fixing system can be reduced, for example, by notifying an operator or the like.

  According to an eighth aspect of the present invention, there is provided a heating source for heating and pressurizing the transfer paper on which the image has been transferred in the image forming unit, and fixing an unfixed image on the transfer paper. A heating rotator that is heated by a source; and a pressure contact rotator that is in pressure contact with the heating rotator, and a fixing device configured to pass the transfer paper through a nip between the heating rotator and the pressure rotator. In the image forming apparatus, the fixing device according to any one of claims 1 to 7 is mounted as the fixing device. With this configuration, a non-contact temperature sensor in the fixing device detects a temperature error due to dirt or the like. Even when an error occurs, monitoring is performed by another temperature sensor, so that an appropriate fixing operation is performed, and it is possible to prevent the occurrence of defective fixing and abnormal images.

  According to a ninth aspect of the present invention, in the image forming apparatus according to the eighth aspect of the present invention, the image forming apparatus further includes a drive control unit that stops the driving of the mechanical system installed in the apparatus at the same time as the driving of the heating source is stopped. With this configuration, the drive of all the mechanical systems is stopped simultaneously with the occurrence of an abnormality, so that transfer paper having an unfixed image is jammed in the middle of the conveyance path or the unfixed image is scattered in the image forming unit. Can be prevented.

  According to a tenth aspect of the present invention, in the image forming apparatus according to the eighth or ninth aspect, a control unit that causes the notification unit provided outside the apparatus main body to notify the stop state simultaneously with the stop. With this configuration, this configuration can promptly notify the operator that the machine is in an abnormal state, so that the machine down time can be reduced.

  According to the present invention, even when the non-contact temperature sensor has detected a temperature error due to dirt or the like, since it is monitored by another temperature sensor, an appropriate fixing operation is performed, fixing failure, abnormal image A fixing device and an image forming apparatus that have a large practical effect, such as preventing occurrence of damage and, in turn, preventing damage to the unit, and allowing the operator to quickly grasp the situation when detecting an abnormality. Can be provided.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram illustrating an overall configuration of an image forming apparatus for explaining an embodiment of the present invention, in which 11 is an apparatus main body of the image forming apparatus, 12 is a paper feed tray for storing transfer paper P, and 13 is a schematic diagram. A manual feed tray for manually feeding the transfer paper P, 14 is an image forming unit, 15 is a fixing device, and 16 is a paper discharge tray.

  In the image forming unit 14, reference numeral 21 denotes a photosensitive belt, 22 denotes an exposure unit that exposes the surface of the photosensitive belt 21 to form a latent image, and 23, 24, 25, and 26 denote black, cyan, magenta, and yellow colors. A developing unit 27 visualizes the latent image with the corresponding toner, and a transfer unit 27 transfers the toner developed image onto the transfer paper P.

  The transfer paper P is fed from the paper feed tray 12 or the manual feed tray 13 and sent to the transfer unit 27 by the transport roller 28, and the toner image formed on the photosensitive belt 21 is transferred to the transfer paper P by the transfer unit 27. Is done. The photographic paper P having a toner image of an unfixed image is heated and pressed by the fixing device 15 to be fixed as described later, and is then discharged to the discharge tray 16 by the discharge roller 29. The

  FIG. 2 is an enlarged configuration diagram showing the first embodiment of the fixing device of FIG. 1 according to the present invention, wherein 1 is a fixing roller which is a heating rotary body incorporating a heater 2 which is a heating source, and 3 is a fixing roller. A pressure roller, which is a pressure-rotating member that is in pressure contact with 1, 4 and 5 are an inlet guide plate and an outlet guide plate for introducing and guiding the transfer paper P into a nip portion between the fixing roller 1 and the pressure roller 3, and 6 is a fixing roller 1. This is a separation plate that acts to peel off the transfer paper P from the paper.

  In the first embodiment, at least two temperature sensors are provided for controlling the temperature of the heater 2 provided on the fixing roller 1. In this example, as shown in FIG. 3, a thermopile 8 that is a non-contact type temperature sensor is installed at the center of the fixing roller 1, and a thermistor 9 that is a contact type temperature sensor is installed beside the thermopile 8. The contact type thermistor 9 is not in contact with the fixing roller 1 when the transfer paper P is passed, but is in contact with or separated from the fixing roller 1 only when the fixing roller 1 is not passing (when not rotating). It can be moved by a mechanism (for example, a solenoid device).

  In FIG. 2, the transfer paper P having the unfixed toner image transferred to the entrance guide plate 4 after the toner image is transferred by the transfer unit 27 is a nip between the rotating fixing roller 1 and the pressure roller 3. By being heated and pressurized in the section, the unfixed toner image is fixed on the transfer paper P, sent to the paper discharge roller 29 shown in FIG. 1 through the exit guide plate 5, and discharged to the paper discharge tray 16. .

  FIG. 4 is a block diagram showing the configuration of the fixing control system in the present embodiment. Temperature detection information from the thermopile 8 and the contact type thermistor 9 is received by a CPU (Central Processing Unit) 31 which is a control unit. A determination of abnormality is detected, and a drive control signal is output to the heater drive unit 32 that turns on and off the heater 2 and the mechanical system drive unit 33 that drives the mechanical system in the fixing device 15 and the image forming apparatus. In addition, when it is determined that an abnormality has been detected, a notification control signal is output to a notification driving unit 34 that drives a display unit such as an operation panel or a notification buzzer provided outside the main body of the image forming apparatus. Yes.

  FIG. 5 is a flowchart relating to the fixing control of this embodiment. When the main switch of the image forming apparatus is turned on and the fixing apparatus 15 is started, the temperature detection information of the fixing roller 1 from the thermopile 8 and the contact type thermistor 9 is the CPU 31. (S1). The CPU 31 monitors the detection abnormality of the thermopile 8 by comparing the detection temperature of the thermopile 8 with the detection temperature of the contact type thermistor 9 (S2).

  That is, the difference between the temperature detected and measured by the thermopile 8 and the temperature detected and measured by the contact type thermistor 9 is calculated as shown in the explanatory diagram of the abnormality determination example of the temperature sensor (thermopile) shown in FIG. When the value exceeds a certain value (± 10 ° C.) (shaded area in FIG. 6), it is determined that the thermopile 8 is in an abnormal state.

  When it is determined that the thermopile 8 is in an abnormal state (NO in S3), all the heaters 2 are turned off with respect to the heater drive unit 32 and the mechanical system drive unit 33, and the transport system, roller A drive stop signal for stopping the drive of the mechanical system such as the rotation mechanism is output (S4). Further, a drive signal is output to the notification drive unit 34 (S5), and the display unit or the notification buzzer is turned on to notify the operator or the like that there is an abnormal state.

  When it is determined that the thermopile 8 is normal (YES in S3), the fixing device 15 continues to operate (S6), and until the predetermined fixing operation ends (S7), the temperature sensor as described above is operated. Monitoring is performed.

  Thus, in the first embodiment, erroneous detection of the non-contact temperature sensor (thermopile) can be prevented before problems such as fixing failure, abnormal image, and unit damage occur.

  FIG. 7 is a configuration diagram of a fixing device according to Embodiment 2 of the present invention. In the following description, members corresponding to those already described are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the second embodiment, an endless fixing belt 37 made of a heat-resistant material is provided between a pair of rotating bodies of a heating roller 36 and a fixing roller 1 including a halogen heater 35 that is a heating source. Note that reference numeral 38 in FIG. 7 denotes a tension roller that applies tension to the fixing belt 37.

  In this example, the surface hardness of the pressure roller 3 is 70 Hs, the surface hardness of the fixing roller 1 is 30 Hs, the heating roller 36 is heated by the halogen heater 35, and the heat is transferred to the pressure roller 3 via the fixing belt 37. It is configured to transmit to the nip part of the.

  Further, as shown in FIG. 8, a thermopile 8 as a non-contact type temperature sensor is installed at the central portion of the heating roller 36 (fixing belt 37), and a contact type thermistor 9 is installed beside it. The contact type thermistor 9 is not in contact with the fixing belt 37 when the transfer paper P is passed, but is in contact with the fixing belt 37 only when the fixing roller 1 and the fixing belt 37 are not rotated. A separation mechanism is provided.

  In the temperature sensor of the second embodiment, the abnormality determination is performed by calculating the difference between the temperature measured by the thermopile 8 and the temperature measured by the contact type thermistor 9 as in the first embodiment, and the value exceeds a certain value. If it is determined that there is an abnormality in the thermopile 8.

  As shown in the configuration diagram of the temperature sensor of the fixing device according to the third embodiment of the present invention shown in FIG. 9, the width through which the maximum size of the transfer paper P that can be used in the fixing roller 1 or the heating roller 36 passes. By disposing the contact type thermistor 9 in the outer area A (longitudinal direction), it is possible to prevent the occurrence of problems such as damage to the sheet passing area of the fixing roller 1 or the heating roller 36 due to the contact of the contact type thermistor 9. it can.

  FIGS. 10A and 10B are explanatory diagrams showing an example of abnormality determination of the temperature sensor (thermopile) in the third embodiment. When the transfer paper P shown in FIG. 10A is passed, FIG. ) And the non-sheet-passing time shown in FIG. 2), the difference between the temperature detected and measured by the thermopile 8 and the temperature detected and measured by the contact-type thermistor 9 is calculated, and the value is calculated as described above. When the determination reference value is exceeded (the hatched area in FIGS. 10A and 10B), it is determined that the thermopile 8 is in an abnormal state.

  FIG. 11 is a configuration diagram of a fixing device according to Embodiment 4 of the present invention. The configuration of Embodiment 2 shown in FIG. 7 is that the contact type thermistor 9 is eliminated as a temperature sensor and a non-contact type temperature sensor (for example, thermopile, non-pile) is used. Only the contact-type thermistor, NC sensor, etc.) are used, and the non-contact-type temperature sensors 41a, 41b are located inside the maximum sheet passing size of the transfer paper P to be used, as shown in FIG. There are at least two sensors (for example, thermopile) 41a, at least one end temperature sensor (for example, a non-contact type thermistor) 41b in the vicinity of the end, and at least two of them. The difference is that the heaters 2a and 2b of the book (shown one by one in the figure) are provided.

  As shown in FIG. 13, the heaters 2a and 2b have different heating distributions, and are constituted by a central heater 2a that heats only the center of the heating roller 36 and an end heater 2b that heats only the end.

  In the fourth embodiment, the non-contact temperature sensors 41a and 41b monitor the temperature of other temperature sensors. Further, at the time of start-up and standby, after the temperature sensor at the center or the end reaches a predetermined temperature, it is determined that the other temperature sensor cannot reach the predetermined temperature within a certain time.

  FIGS. 14A, 14B, and 14C are explanatory diagrams showing an example of temperature sensor abnormality determination in the fourth embodiment. FIG. 14A is a stand-up state, FIG. 14B is a stand-by state, and FIG. 14 (c) is a judgment criterion at the time of paper passing, and the difference between the temperatures detected and measured by the non-contact temperature sensors 41a and 41b is calculated, and the value exceeds the judgment criterion value. In the case (the hatched area in FIGS. 14A to 14C), it is determined that the corresponding temperature sensor is in an abnormal state.

  At the time of paper passing, as shown in FIG. 14C, the abnormality determination setting value varies depending on the paper size. That is, when the edge of the transfer paper comes outside the sensor position of the edge temperature sensor 41b, an abnormality occurs when the temperature difference between the center temperature sensor 41a and the edge temperature sensor 41b is not within a certain temperature range (A). If the edge of the transfer paper is located inside the sensor position of the edge temperature sensor 41b, the temperature difference between the temperature sensor 41a and the edge temperature sensor 41b is not within a certain temperature range (b). If it is judged abnormal.

  FIG. 15 is a timing chart of the specific operation of each part in steps (S4) and (S5) of the operation flow shown in FIG. 5 of the present embodiment, and is driven simultaneously with the heater off due to the abnormality detection of the heaters 2, 2a and 2b. The transfer paper P on which an unfixed image is placed is fixed to the fixing device by stopping the driving of all the mechanical systems (each roller of the fixing device, the paper discharge roller, each part of the image forming unit, the paper feeding / conveying roller). It is possible to prevent damage to the mechanical system due to clogging before 15 or scattering of an unfixed image.

  Also, as shown in FIG. 16, simultaneously with turning off the heaters when an abnormality is detected in the heaters 2, 2a, 2b, the display unit on the operation panel or a notification buzzer is turned on to notify the service call and It is possible to reduce the machine down time by grasping the status and promptly performing the response process.

  The present invention is applied to a heat roller fixing unit such as a heat roller type and a belt fixing type used for a fixing device in an image forming apparatus such as a laser printer, a copying machine, a facsimile machine, and the like. It is effective for use in a heat and pressure fixing unit having a function and an image forming apparatus equipped with the same.

1 is a schematic configuration diagram illustrating an overall configuration of an image forming apparatus for describing an embodiment of the present invention. 1 is a configuration diagram of a first embodiment of a fixing device according to the present invention. Installation configuration diagram of temperature sensor in embodiment 1 A block diagram showing a configuration of a fixing control system in the present embodiment Flowchart related to fixing control of this embodiment Explanatory drawing of the abnormality determination example of the temperature sensor in Embodiment 1. Configuration diagram of a fixing device in Embodiment 2 of the present invention Installation configuration diagram of temperature sensor in embodiment 2 Installation configuration diagram of temperature sensor of fixing device in Embodiment 3 of the present invention (A), (b) is explanatory drawing which shows the abnormality determination example of the temperature sensor in Embodiment 3. Configuration of Fixing Device in Embodiment 4 of the Present Invention Installation configuration diagram of temperature sensor in embodiment 4 Configuration diagram of heater in embodiment 4 (A)-(c) is explanatory drawing which shows the abnormality determination example of the temperature sensor in Embodiment 4. Specific operation timing chart in the operation flow of this embodiment Other timing charts of specific operations in the operation flow of this embodiment Schematic configuration diagram of a conventional fixing device FIG. 17 is an explanatory diagram showing a relationship between a fixing roller and a temperature sensor in the fixing device of FIG.

Explanation of symbols

1 Fixing roller 2 Heating heater 2a Heating heater (center heater)
2b Heater (end heater)
3 Pressure roller 8 Thermopile 9 Thermistor 14 Image forming unit 15 Fixing device 27 Transfer unit 31 CPU
32 Heater drive unit 33 Mechanical system drive unit 34 Notification drive unit 36 Heating roller 37 Fixing belt 41a Non-contact temperature sensor (central temperature sensor)
41b Non-contact temperature sensor (end temperature sensor)

Claims (10)

A heating rotator provided with a heating source and a pressure rotator that is in pressure contact with the heating rotator, and passing the transfer paper through a nip between the heating rotator and the pressure rotator, thereby allowing the transfer paper to pass over the transfer paper. In a fixing device for fixing an unfixed image,
At least two temperature sensors for detecting the temperature of the heating rotating body, wherein at least one of the temperature sensors is a non-contact type temperature sensor, and the detection temperature of the non-contact type temperature sensor is based on the detection temperature of another temperature sensor; And a controller that stops heating and rotating when an abnormality occurs. A heat-resistant endless belt stretched between at least two rotating bodies, at least one press-contacting body pressed against at least one of the rotating bodies across the endless belt, and heating for heating the endless belt A fixing device that fixes a non-fixed image on the transfer paper by passing the transfer paper through a nip between the endless belt and the press contact member,
Comprising at least two temperature sensors for detecting the temperature of the endless belt, at least one of which is a non-contact type temperature sensor, and monitoring the detection temperature of the non-contact type temperature sensor based on the detection temperature of another temperature sensor; A fixing device comprising a controller that stops heating driving and rotational driving when an abnormality occurs. A heat-resistant endless belt stretched between at least two rotating bodies, at least one press-contacting body pressed against at least one of the rotating bodies across the endless belt, and a heat source for heating the endless belt A fixing device for fixing an unfixed image on the transfer paper by passing the transfer paper through a nip between the endless belt and the pressure contact member,
At least two heating elements are provided in the heating source, and at least two temperature sensors are provided. The temperature sensors detect the temperature of the endless belt, and at least two of the temperature sensors are non-contact type temperature sensors. As described above, the detection temperatures of the other non-contact type temperature sensors can be monitored, the temperature of each of the heating bodies is controlled based on the detection temperature of each of the temperature sensors, and the detection detection of the non-contact type temperature sensor A fixing device comprising: a control unit that stops heating driving and rotational driving when it is detected that an abnormality has occurred in one of the two based on temperature.   The fixing device according to claim 1, wherein a temperature sensor other than the non-contact type temperature sensor is a contact type temperature sensor.   The fixing device according to claim 4, wherein the contact-type temperature sensor is installed outside a sheet passing range of the transfer paper.   The fixing device according to claim 1, wherein the control unit stops all driving systems simultaneously with stopping the heating of the heating source.   The fixing device according to claim 1, wherein the control unit outputs an abnormality notification information signal simultaneously with the stop. In order to heat and press the transfer paper on which image transfer has been performed in the image forming unit and fix an unfixed image on the transfer paper, a heating source and a heating rotator overheated by the heating source And a pressure contact rotator that is in pressure contact with the heating rotator, and an image forming apparatus including a fixing device configured to pass the transfer paper through a nip between the heating rotator and the pressure rotator.
An image forming apparatus comprising the fixing device according to claim 1 as the fixing device.   The image forming apparatus according to claim 8, further comprising a drive control unit configured to stop driving of a mechanical system installed in the apparatus at the same time as driving of the heating source is stopped.   The image forming apparatus according to claim 8, further comprising a control unit that causes a notification unit provided outside the apparatus main body to notify the stop state simultaneously with the stop.

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