Image forming apparatus

Abstract

Provided is an image forming apparatus capable of performing processing for cutting a printing medium on which double-sided printing is performed. An image forming apparatus includes: an image forming section (4) including a photosensitive drum (46), a developing roller (44R) that supplies toner onto the photosensitive drum, a transfer section (42) that transfers the toner supplied onto the photosensitive drum to a printing medium (S), and a fixing section (45) that fixes the toner transferred to the printing medium on the printing medium; a processing unit (100) that is provided downstream of the fixing unit in the conveying direction of the printing medium and performs processing for cutting the printing medium; and a control unit (C) that executes a double-sided printing process in which printing is executed on both sides of the printing medium by the image forming unit, and after the double-sided printing process is executed, the control unit executes a processing process in which processing for cutting the printing medium is performed by the processing unit.

Description

Technical Field

[0001] The present invention relates to an image forming device. Background Art

[0002] In an image forming apparatus such as an electronic photo printer, a cutting unit for cutting a sheet is sometimes installed. In addition, the following patent document 1 discloses an image forming apparatus that, after performing image forming processing on a sheet, generates two sheets each subjected to image forming processing by cutting the sheets with a cutting unit and discharges the sheets.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-186448

[0006] Technical problem to be solved by the invention

[0007] However, in the above-mentioned conventional image forming apparatus, it is not possible to cut the sheet after image forming processing is performed on both the front and back sides of the sheet. Summary of the invention

[0008] An object of the present invention is to provide an image forming apparatus capable of performing a process for cutting a print medium on which double-sided printing has been performed.

[0009] Technical means for solving technical problems

[0010] In order to solve the above-mentioned technical problems, the image forming device of the first mode of the present invention comprises: an image forming unit, which has a photosensitive drum, a developing roller, a transfer unit and a fixing unit, the developing roller supplies toner to the photosensitive drum, the transfer unit transfers the toner supplied to the photosensitive drum to the printing medium, and the fixing unit fixes the toner transferred to the printing medium on the printing medium; a processing unit, which is arranged downstream of the fixing unit in the conveying direction of the printing medium and performs processing for cutting the printing medium; and a control unit, which performs a double-sided printing process, and the double-sided printing process is performed by the image forming unit on both sides of the printing medium, and the control unit performs a processing process after performing the double-sided printing process, and the processing process is performed by the processing unit to cut the printing medium.

[0011] The image forming device of the second mode of the present invention may also be that in the image forming device of the first mode, the double-sided printing process includes: a first image forming process, which forms an image on one side of the printing medium through the image forming unit; and a second image forming process, which forms an image on the other side of the printing medium through the image forming unit after the first image forming process.

[0012] The image forming device of the third mode of the present invention may also be, in the image forming device of the first mode or the second mode, the processing unit is configured to cut the printing medium, and the processing is a process in which the printing medium is cut by the processing unit into a first printing medium and a second printing medium in front and behind in the conveying direction.

[0013] The image forming device of the fourth mode of the present invention may also be, in the image forming device of the second mode, further comprising: a main body casing having a first discharge portion for discharging the printing medium that has passed through the fixing portion; a first conveying path, the first conveying path being used to convey the printing medium that has passed through the fixing portion toward the first discharge portion; and a second conveying path different from the first conveying path, the second conveying path being used to convey the printing medium that has passed through the fixing portion toward the photosensitive drum again after the first image forming process.

[0014] The image forming device of the fifth embodiment of the present invention may also be, in the image forming device of the fourth embodiment, further comprising a discharge roller, which transports the printing medium that has passed the fixing section toward the first discharge section, and after the first image forming process and before the second image forming process, the control section performs a reverse transport process, and the reverse transport process cuts the printing medium back from the first transport path and transports it to the second transport path through the discharge roller.

[0015] The image forming device of the sixth mode of the present invention may also be, in the image forming device of the fourth mode, further comprising a third conveying path different from the first conveying path, the third conveying path being used to convey the printing medium that has passed the fixing section toward the processing section, and the processing section being arranged on the third conveying path.

[0016] An image forming apparatus according to a seventh aspect of the present invention may be the image forming apparatus according to the fourth aspect, wherein the processing section is provided in the first transport path.

[0017] The image forming device of the eighth embodiment of the present invention may also be an image forming device of any one of the fourth to seventh embodiments, wherein the image forming unit has a drum cartridge or a toner cartridge, the drum cartridge has the photosensitive drum, the toner cartridge has the developing roller, the main body housing also has a front cover and a rear cover, the front cover is capable of opening and closing an opening for loading and unloading the drum cartridge or the toner cartridge, the rear cover is capable of closing a second discharge portion different from the first discharge portion, the second discharge portion being used to discharge the print medium that has passed through the fixing unit, and when the front cover closes the opening and the rear cover closes the second discharge portion, the control unit executes the first image forming process, the second image forming process and the processing process.

[0018] The image forming device of the ninth mode of the present invention may also be, in the image forming device of the second mode, further comprising a detection unit, which is arranged upstream of the image forming unit in the conveying direction and can detect the length of the printing medium in the conveying direction, the control unit performs a detection process, and the detection process detects the length of the printing medium in the conveying direction by the detection unit, and when the length of the printing medium detected by the detection process is longer than a specified length, the control unit performs the first image forming process, the second image forming process and the processing process.

[0019] The image forming apparatus according to a tenth aspect of the present invention may be the image forming apparatus according to the second aspect, further comprising a main motor that drives the photosensitive drum, the developing roller, the transfer section, or the fixing section.

[0020] The image forming device of the eleventh mode of the present invention may also be, in the image forming device of the tenth mode, the processing part has: a cutting blade; a slide, which holds the cutting blade and can move in a prescribed direction; and a slide motor different from the main motor, which drives the slide.

[0021] The image forming apparatus according to a twelfth aspect of the present invention may be the image forming apparatus according to the eleventh aspect, wherein the control section drives the carriage motor after stopping the main motor when executing the processing.

[0022] The image forming device of the thirteenth mode of the present invention may also be an image forming device of any one of the tenth to twelfth modes, wherein the image forming unit further includes an exposure unit, which exposes the photosensitive drum, and the exposure unit has: a polygonal mirror, which is used to irradiate a specified light beam to the photosensitive drum; and a polygonal mirror motor different from the main motor, which drives the polygonal mirror to rotate.

[0023] The image forming device of the fourteenth embodiment of the present invention may also be, in the image forming device of the thirteenth embodiment, when receiving a printing job for multiple sheets of the printing medium, the control unit drives the polygonal mirror motor if the control unit performs the first image forming process on the second sheet of the printing medium through the image forming unit when performing the processing on the first sheet of the printing medium.

[0024] The image forming device of the fifteenth embodiment of the present invention may also be, in the image forming device of the thirteenth embodiment, when receiving a printing job for multiple sheets of the printing media, the control unit stops the polygonal mirror motor if the image forming unit does not perform the first image forming process on the second sheet of the printing medium when performing the processing on the first sheet of the printing medium.

[0025] The image forming apparatus according to a sixteenth aspect of the present invention may be, in the image forming apparatus according to the first aspect or the second aspect, wherein the fixing section includes a heater for heating the print medium, and the control section stops the heater when executing the processing.

[0026] The seventeenth embodiment of the image forming device of the present invention may also be, in the fifth embodiment of the image forming device, when a printing job for the printing medium is received, when the printing job contains 4N+1 pages of printing data, N is an integer greater than 0, the control unit, when it is determined that the printing data for the printing medium on which the processing has not been performed is the printing data of the final page, executes a process including the following processes: a third image forming process of forming an image of the final page on any one side of the printing medium by the image forming unit; and performing the processing by the processing unit on the printing medium after the third image forming process without performing the reverse conveying process.

[0027] In addition, in the conventional image forming apparatus as described above, it is not possible to hold the cut printing medium inside the image forming apparatus and form an image on the held cut printing medium. Therefore, there is a second technical problem: to realize an image forming apparatus that is more convenient than conventional image forming apparatuses.

[0028] In order to solve the above-mentioned second technical problem, the image forming device of the eighteenth mode of the present invention comprises: an image forming unit, the image forming unit has a photosensitive drum, a developing roller, a transfer unit and a fixing unit, the developing roller supplies toner to the photosensitive drum, the transfer unit transfers the toner supplied to the photosensitive drum to a printing medium, and the fixing unit fixes the toner transferred to the printing medium on the printing medium; a cutting unit, the cutting unit is arranged downstream of the fixing unit in the conveying direction of the printing medium and cuts the printing medium; a main body shell, the main body shell has a discharge tray, the discharge tray is used to discharge the printing medium that has passed the fixing unit; a first conveying path, the first conveying path is used to convey the printing medium that has passed the fixing unit toward the discharge tray; a second conveying path different from the first conveying path, the second conveying path is used to convey the printing medium that has passed the fixing unit toward the photosensitive drum again; and a control unit, which executes a process including the following processes: a first image forming process, in which the image forming unit forms an image on one side of the print medium; a cutting process, in which, after the first image forming process, the print medium is cut by the cutting unit into a first print medium and a second print medium located downstream in the conveying direction compared with the first print medium; a holding process, in which, after the cutting process, the first print medium is conveyed to the second conveying path and the first print medium is held in the second conveying path; and a re-inversion process, in which, after the holding process, the image forming unit forms an image on one side of the first print medium held in the second conveying path, and the first print medium held in the second conveying path is conveyed to the second conveying path again and the first print medium is reversed.

[0029] The image forming apparatus according to a nineteenth aspect of the present invention may be the image forming apparatus according to the eighteenth aspect, wherein the control unit holds the first print medium, on which no image has been formed by the first image forming process, in the second transport path through the holding process.

[0030] The image forming device of the twentieth aspect of the present invention may be, in the image forming device of the eighteenth aspect, wherein the control unit further executes a first discharge process that discharges the second print medium to the discharge tray after the cutting process and before the holding process.

[0031] The image forming device of the twenty-first embodiment of the present invention may also be, in the image forming device of the eighteenth embodiment, the main body shell has a feed tray, which is arranged upstream of the image forming unit in the conveying direction and can accommodate the printing medium, and the control unit also performs the following processing: a second image forming processing, after the first image forming processing, the second image forming processing is used to form an image on the other side of the printing medium through the image forming unit; and a second discharge processing, after the holding processing and before the second image forming processing, when the first image forming processing and the second image forming processing are performed on the printing medium taken out from the feed tray, the second discharge processing discharges the first printing medium held in the second conveying path to the discharge tray without forming an image on the first printing medium through the image forming unit.

[0032] The image forming device of the twenty-second embodiment of the present invention may also be, in the image forming device of the eighteenth embodiment or the twenty-first embodiment, the control unit also performs a determination process, which determines whether the re-reversal process is performed on the first printing medium based on information indicating the number of times the first printing medium has passed through the fixing unit.

[0033] The image forming device of the twenty-third embodiment of the present invention may also be, in the image forming device of the twenty-second embodiment, further comprising a detection unit, which is arranged downstream of the fixing unit and detects the passage of the first printing medium, and the control unit performs the re-reversal processing when it is determined in the determination processing that the number of times the first printing medium has passed through the detection unit is below a predetermined threshold value.

[0034] The image forming apparatus of the twenty-fourth aspect of the present invention may be the image forming apparatus of the twenty-second aspect, further comprising a detection unit which is provided downstream of the fixing unit and detects the passage of the printing medium. If the control unit determines in the determination process that the number of times the first printing medium has passed through the detection unit exceeds a predetermined threshold, the control unit does not execute the re-reversal process.

[0035] The image forming device of the twenty-fifth aspect of the present invention may be, in the image forming device of the twenty-fourth aspect, wherein the control unit executes the second discharge process when the control unit determines in the determination process that the number of times the first print medium has passed through the detection unit exceeds a predetermined threshold value.

[0036] The image forming device of the twenty-sixth embodiment of the present invention may also be, in the image forming device of the eighteenth embodiment, the fixing unit has a heating roller for heating the printing medium, and the control unit makes the temperature of the heating roller of the fixing unit in the re-reversal process lower than the temperature of the heating roller of the fixing unit in the first image forming process.

[0037] The image forming device of the twenty-seventh embodiment of the present invention may also be, in the image forming device of the twenty-first embodiment, the fixing unit has a heating roller for heating the printing medium, and the control unit makes the temperature of the heating roller of the fixing unit in the second discharge process lower than the temperature of the heating roller of the fixing unit in the first image forming process.

[0038] In addition, in the above-mentioned conventional image forming apparatus, there is room for improvement in the timing of ejecting the cut sheet and feeding the next sheet. Therefore, there is a third technical problem: to provide an image forming apparatus that improves the timing of ejecting the processed printing medium for cutting and the timing of feeding the next printing medium compared with the conventional method.

[0039] In order to solve the third technical problem mentioned above, the image forming device of the twenty-eighth mode of the present invention comprises: a conveying unit, which conveys a printing medium; a conveying path, which is used to convey the printing medium in a conveying direction; an image forming unit, which is arranged on the conveying path and has a photosensitive drum, a developing roller for supplying toner to the photosensitive drum, a transfer unit for transferring the toner supplied to the photosensitive drum to the printing medium, and a fixing unit for fixing the toner transferred to the printing medium on the printing medium; a processing unit, which is arranged downstream of the image forming unit and performs processing for cutting the printing medium; and a control unit. The control unit executes an image forming process and a processing process, wherein the image forming process forms an image on the printing medium through the image forming unit, and after the image forming process, the processing process is performed by the processing unit to cut the printing medium into a first printing medium and a second printing medium in front and behind in the conveying direction, and when the processing process is completed, the control unit synchronously executes the start of supplying the next printing medium and the start of discharging the first printing medium and the second printing medium processed by the processing process.

[0040] The image forming apparatus according to the twenty-ninth aspect of the present invention may be, in the image forming apparatus according to the twenty-eighth aspect, configured such that: the processing is a cutting process of cutting the print medium into the first print medium and the second print medium.

[0041] The image forming apparatus of the 30th aspect of the present invention may be, in the image forming apparatus of the 29th aspect, the processing section includes a cutting blade and a carriage, the carriage can hold the cutting blade and be driven from an initial position in a scanning direction, the scanning direction being the same direction as the axial direction of the photosensitive drum. In the cutting process, the control section moves the carriage from the initial position in the scanning direction to cut the printing medium, and when the cutting process is completed, the control section synchronously executes the start of supplying the next printing medium and the start of discharging the first printing medium and the second printing medium cut by the cutting process before the carriage returns to the initial position.

[0042] The image forming device of the thirty-first embodiment of the present invention may also be, in the image forming device of the thirtieth embodiment, when the rear end in the conveying direction of the second printing medium cut by the cutting process crosses the scanning track of the cutting blade, the control unit returns the slide from the cutting completion position which is the position where the cutting process is completed.

[0043] The image forming apparatus of the thirty-second aspect of the present invention may be the image forming apparatus of any one of the twenty-eighth aspect to the thirtieth aspect, further comprising: a feed tray on which a print medium is placed; and a pickup roller on which the print medium placed on the feed tray is picked up. When the processing is completed, the control unit synchronously starts to discharge the first print medium and the second print medium processed by the processing and starts to supply the next print medium by driving the pickup roller.

[0044] The image forming device of the thirty-third aspect of the present invention may also be, in the image forming device of the twenty-ninth aspect or the thirtieth aspect, further comprising: a feed tray on which a print medium is placed; a pickup roller which picks up the print medium placed on the feed tray; a discharge roller which discharges the print medium to the discharge tray; a first motor which drives the pickup roller; and a second motor which is different from the first motor and drives the discharge roller. At the timing when the cutting process is completed, the control unit starts the rotation of the first motor, and starts the rotation of the second motor in synchronization with the rotation speed of the first motor becoming a rotation speed suitable for driving the pickup roller, thereby driving the discharge roller.

[0045] The image forming device of the thirty-fourth embodiment of the present invention may also be, in the image forming device of the thirty-third embodiment, when the rotation speed of the first motor becomes a rotation speed suitable for driving the pickup roller, the control unit causes the pickup roller to clamp the next printing medium, thereby starting the supply of the next printing medium.

[0046] The image forming apparatus of the thirty-fifth aspect of the present invention may be, in the image forming apparatus of the twenty-ninth aspect or the thirtieth aspect, further comprising: a feed tray on which a print medium is placed; a pickup roller which picks up the print medium placed on the feed tray; a discharge roller which discharges the print medium to the discharge tray; and a third motor which drives the pickup roller and the discharge roller. When the cutting process is completed, the control unit starts driving the pickup roller and the discharge roller by the third motor.

[0047] The image forming apparatus of the thirty-sixth aspect of the present invention may be the image forming apparatus of the thirty-fifth aspect, further comprising a clutch connecting the third motor and the pickup roller. When the rotation speed of the third motor becomes a rotation speed suitable for driving the pickup roller, the control unit switches the clutch on to connect the pickup roller and the third motor to start supplying the next print medium.

[0048] The image forming apparatus of the thirty-seventh aspect of the present invention may be, in the image forming apparatus of the thirty-second aspect, further comprising: a first motor that drives the pickup roller; and a clutch that connects the first motor and the pickup roller. When the rotation speed of the first motor becomes a rotation speed suitable for driving the pickup roller, the control unit switches the clutch on to connect the pickup roller and the first motor to start supplying the next print medium.

[0049] The image forming device of the thirty-eighth embodiment of the present invention may also be, in the image forming device of the thirty-second embodiment, the plurality of conveying units are configured as follows: as the configuration position of the conveying unit in the conveying path moves toward the downstream side compared to the conveying unit arranged on the upstream side, the conveying speed of the conveying unit for the printing medium increases.

[0050] The image forming apparatus of the thirty-ninth aspect of the present invention may be the image forming apparatus of the thirty-second aspect, further comprising a discharge roller that discharges the print medium to a discharge tray. Of the pickup roller and the discharge roller, the discharge roller has a faster conveying speed for the print medium.

[0051] Effects of the Invention

[0052] According to the image forming apparatus of the first aspect, after printing is performed on both sides of the print medium by the image forming section, the processing section provided on the downstream side of the printing medium conveying direction relative to the fixing section performs processing for cutting the print medium. Thus, an image forming apparatus capable of performing processing for cutting the print medium on which double-sided printing is performed can be constructed.

[0053] According to the image forming apparatus of the second embodiment, an image is formed on one side of a printing medium by the first image forming process, and an image is formed on the other side of the printing medium by the second image forming process. Thus, double-sided printing can be reliably performed on the printing medium.

[0054] According to the image forming apparatus of the third aspect, the print medium can be cut into the first print medium and the second print medium through processing.

[0055] According to the image forming apparatus of the fourth aspect, by using the first conveyance path and the second conveyance path, it is possible to reliably perform double-sided printing on a print medium.

[0056] According to the image forming apparatus of the fifth aspect, the printing medium can be sequentially conveyed to the first conveyance path and the second conveyance path by the reverse conveyance process, thereby enabling more reliable double-sided printing to be performed on the printing medium.

[0057] According to the image forming apparatus of the sixth aspect, the printing medium can be conveyed to the processing unit provided in the third conveying path separately from the first conveying path. Therefore, the printing medium can be conveyed to the processing unit with high accuracy. Thus, the processing position of the processing unit in the printing medium can be adjusted with high accuracy to perform processing.

[0058] According to the image forming apparatus of the seventh aspect, the processing unit is provided in the first conveying path for conveying the print medium toward the first discharge unit. Therefore, the provision of a dedicated conveying path for guiding the print medium to the processing unit can be omitted. Thus, the image forming apparatus can be easily miniaturized.

[0059] According to the image forming apparatus of the eighth aspect, the possibility of a user inserting a hand or the like into the interior of the main body housing when performing the first image forming process, the second image forming process, and the processing process can be greatly reduced. Thus, double-sided printing on the print medium and processing for cutting the print medium can be safely performed.

[0060] According to the image forming apparatus of the ninth aspect, the length of the transported printing medium can be acquired through detection processing. Thus, based on the acquired printing medium length, the first image forming processing, the second image forming processing, and the processing processing can be performed on the printing medium with high accuracy. Thus, the printing accuracy of the printing medium on which the processing processing is performed can be improved.

[0061] According to the image forming apparatus of the tenth aspect, the control unit controls the driving of the main motor, thereby enabling the first image forming process and the second image forming process to be executed with high accuracy on the print medium, thereby improving the printing accuracy on the print medium.

[0062] According to the image forming apparatus of the eleventh aspect, the processing by the processing section can be independently executed, and the processing can be appropriately performed.

[0063] According to the image forming apparatus of the twelfth aspect, the processing by the processing section can be independently performed more reliably. Thus, the processing can be executed more appropriately.

[0064] According to the image forming apparatus of the thirteenth aspect, the control unit can drive the polygonal mirror motor independently of the main motor. Thus, the exposure unit can more appropriately expose the photosensitive drum. Therefore, the image quality of double-sided printing of the printing medium can be easily improved.

[0065] According to the image forming apparatus of the fourteenth aspect, the control unit continues to drive the polygonal mirror motor when the first print medium and the second print medium are processed continuously. Thus, even when the first print medium and the second print medium are processed continuously, the reduction in the processing capacity of the image forming apparatus can be greatly suppressed.

[0066] According to the image forming apparatus of the fifteenth aspect, when the control unit determines that the first image forming process is not executed after the processing process, the polygon motor is stopped. This makes it possible to easily achieve power saving of the image forming apparatus.

[0067] According to the image forming apparatus of the sixteenth aspect, the control unit stops the heater when executing the processing. This makes it possible to easily achieve power saving of the image forming apparatus.

[0068] According to the image forming apparatus of the seventeenth aspect, the control unit omits the reverse conveyance process when the number of remaining pages of the print data is one page. This can improve the processing capability of the image forming apparatus.

[0069] According to the image forming apparatus of the eighteenth aspect, the first printing medium held by the second conveying path is conveyed to the first conveying path once by performing a re-reversal process, and then conveyed to the first conveying path again via the second conveying path. The first printing medium conveyed to the first conveying path again can be conveyed in a manner that one surface of the first printing medium faces the transfer unit of the image forming apparatus. Thus, an image forming apparatus with improved convenience compared to conventional image forming apparatuses can be provided.

[0070] According to the image forming apparatus of the nineteenth aspect, the first print medium on which an image has not been formed by the first image forming process is held by the second conveying path by the holding process, whereby no image is formed on the first print medium held by the holding process. Therefore, even if the first image forming process is performed after the re-inversion process, a double image is not formed on one side of the first print medium. Thus, the concern that the quality of the image formed on one side of the first print medium is degraded can be reduced.

[0071] According to the image forming apparatus of the twentieth aspect, by executing the first discharge process, the second print medium is discharged to the discharge tray before the holding process is performed. Therefore, only the first print medium can be held in the second conveying path. That is, the concern that the first print medium and the second print medium collide in the second conveying path can be reduced. Thus, the possibility of clogging in the second conveying path can be reduced.

[0072] According to the image forming device of the twenty-first mode, by executing the second discharge process, when an image is formed on the front and back sides of the paper taken out from the feed tray, the first print medium held by the second conveying path is first discharged to the discharge tray. Therefore, even if the print medium taken out from the feed tray is conveyed to the second conveying path, the print medium will not collide with the first print medium. Thus, the possibility of clogging in the second conveying path can be reduced. In addition, the image that should be formed on the back side of the print medium taken out from the feed tray will not be formed on the first print medium. Thus, the quality degradation of the image formed on the print medium can be reduced.

[0073] According to the image forming apparatus of the twenty-second aspect, by executing the determination process, it is determined whether to perform the re-reversal process on the first printing medium based on the number of times the first printing medium passes through the fixing unit. Therefore, the first image forming process can be performed in consideration of the influence of the heat of the fixing unit on the first printing medium. Thus, the quality degradation of the image formed on the first printing medium can be reduced.

[0074] According to the image forming apparatus of the twenty-third aspect, when it is determined that the number of times the image has passed through the detection unit is less than a predetermined threshold value, the re-reversal process is performed, thereby making it possible to perform the re-reversal process only on the first printing medium determined to be less affected by the heat of the fixing unit. In other words, the first image forming process is performed on the first printing medium less affected by the heat of the fixing unit. Thus, it is possible to reduce the degradation of the quality of the image formed on the first printing medium.

[0075] According to the image forming apparatus of the twenty-fourth aspect, the re-reversal process is not performed when it is determined that the number of times the medium has passed through the fixing unit exceeds a predetermined threshold value, thereby not performing the re-reversal process on the first printing medium determined to be greatly affected by the heat of the fixing unit. In other words, the first image forming process is not performed on the first printing medium greatly affected by the heat of the fixing unit. Thus, it is possible to reduce the degradation of the quality of the image formed on the first printing medium.

[0076] According to the image forming apparatus of the twenty-fifth aspect, the second discharge process is executed when it is determined that the number of times the first printing medium has passed through the fixing unit exceeds a predetermined threshold value, thereby executing the second discharge process for the first printing medium determined to be greatly affected by the heat of the fixing unit. Therefore, the first printing medium can be discharged to the discharge tray without executing the image forming process for the first printing medium greatly affected by the heat.

[0077] According to the image forming apparatus of the twenty-sixth aspect, the temperature of the heating roller of the fixing unit during the re-reversal process is lowered, thereby reducing the thermal influence on the first printing medium caused by the first printing medium passing through the fixing unit during the re-reversal process. As a result, the quality degradation of the image formed on the first printing medium can be reduced.

[0078] According to the image forming apparatus of the twenty-seventh aspect, the temperature of the heating roller of the fixing unit in the second ejection process is reduced, so that when the first printing medium on which an image is not formed passes through the fixing unit in the second ejection process, heat is not applied to the heating roller. Thus, the power consumption of the fixing unit can be reduced.

[0079] According to the image forming apparatus of the twenty-eighth aspect, at the timing when the processing is completed, the control unit synchronously executes the start of supplying the next printing medium and the start of discharging the printing medium processed by the processing. Thus, the timing of discharging the processed printing medium and the timing of supplying the next printing medium can be improved compared with the past.

[0080] According to the image forming apparatus of the twenty-ninth aspect, the print medium can be cut into the first print medium and the second print medium through the processing.

[0081] According to the image forming apparatus of the thirtieth aspect, at the timing of the completion of the cutting process, the control unit can synchronously execute the start of the supply of the next printing medium and the start of the discharge of the printing medium cut by the cutting process before the carriage returns to the initial position. As a result, the timing of discharging the divided printing medium and the timing of supplying the next printing medium can be improved compared with the past. In addition, the timing of supplying the next printing medium and discharging the cut printing medium can be advanced by the time the carriage returns to the initial position compared with the past.

[0082] According to the image forming apparatus of the thirty-first aspect, the control unit returns the carriage from the cutting completion position to the initial position at the timing when the rear end of the second printing medium cut by the cutting process passes over the scanning track of the cutting blade. Thus, the carriage can be returned to the initial position at the most appropriate timing, and the timing of discharging the processed printing medium and the timing of supplying the next printing medium can be improved compared with the past.

[0083] According to the image forming apparatus of the thirty-second aspect, the control unit starts supplying the printing medium by driving the pickup roller. Thus, the printing medium placed on the feed tray can be smoothly picked up. Thus, compared with the past, it is easy to improve the timing of discharging the processed printing medium and the timing of supplying the next printing medium.

[0084] According to the image forming apparatus of the thirty-third aspect, at the time when the cutting process is completed, the control unit starts the rotation of the second motor to drive the discharge roller in synchronization with the rotation speed becoming suitable for driving the pickup roller. Thus, the discharge roller can be driven while ensuring the rotation speed of the pickup roller. Therefore, compared with the past, the timing of discharging the processed printing medium and the timing of supplying the next printing medium can be improved.

[0085] According to the image forming apparatus of the thirty-fourth aspect, the rotation speed of the first motor at the time of causing the pickup roller to nip the next print medium is set to a rotation speed suitable for driving the pickup roller, thereby enabling the next print medium to be fed satisfactorily.

[0086] According to the image forming apparatus of the thirty-fifth aspect, the control unit drives the pickup roller and the discharge roller via the third motor, thereby making it easier to drive the pickup roller and the discharge roller simultaneously than when controlling motors connected to the pickup roller and the discharge roller separately.

[0087] According to the thirty-sixth embodiment of the image forming apparatus, a clutch is provided for connecting the third motor and the pickup roller. Therefore, in a configuration for simultaneously driving the pickup roller and the discharge roller, the control unit can wait until the rotation speed of the third motor becomes a rotation speed suitable for driving the pickup roller.

[0088] According to the image forming apparatus of the thirty-seventh aspect, the clutch connecting the first motor and the pickup roller is provided, so the control unit can wait until the rotation speed of the first motor reaches a rotation speed suitable for driving the pickup roller.

[0089] According to the image forming device of the thirty-eighth embodiment, the conveying speed of the conveying section arranged on the downstream side in the conveying path can be increased. Thus, the print medium can be conveyed in a manner that the print medium supplied by the pickup roller does not catch up with other print media conveyed on the upstream side. That is, the interval between the print media used to convey the print medium can be appropriately ensured. In addition, by increasing the conveying speed of the conveying section on the downstream side, the print medium being conveyed can be stretched from the downstream side. Thus, the deflection of the print medium during conveyance can be suppressed, and the clogging of the print medium can be reduced.

[0090] According to the image forming apparatus of the thirty-ninth aspect, the delivery roller conveys the print medium faster than the pickup roller, so the print medium supplied by the pickup roller does not catch up with the other print medium conveyed by the discharge roller. That is, the interval between the print media for conveying the print medium can be appropriately ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0091] Figure 1 It is a diagram for explaining a schematic configuration of an image forming apparatus according to a first embodiment of the present invention.

[0092] Figure 2 This is a flowchart showing an operation example of the image forming apparatus according to the first embodiment.

[0093] Figure 3 is a flowchart showing an example of the operation of the image forming apparatus according to the first embodiment, and shows the following Figure 2 The operation example of part A is shown.

[0094] Figure 4 is a flowchart showing an example of the operation of the image forming apparatus according to the first embodiment, and shows the following Figure 3 A specific operation example of S12 is shown.

[0095] Figure 5 is a flowchart showing an example of the operation of the image forming apparatus according to the first embodiment, and shows the following Figure 3 A specific operation example of S16 is shown.

[0096] Figure 6 is a flowchart showing an example of operation of the image forming apparatus according to the first embodiment, Figure 3 A specific operation example of S17 is shown.

[0097] Figure 7 is a flowchart showing an example of operation of the image forming apparatus according to the first embodiment, Figure 3 A specific operation example of S18 is shown.

[0098] Figure 8It is a diagram for explaining a schematic configuration of an image forming apparatus according to a second embodiment and a third embodiment of the present invention.

[0099] Fig. 9 This is a flowchart showing an operation example of the image forming apparatus according to the third embodiment, and shows a flow of control by the control unit during initialization processing.

[0100] Fig.10 This is a flowchart showing an operation example of the image forming apparatus according to the third embodiment, and shows a control flow of the control unit when receiving a print job.

[0101] Fig.11 This is a flowchart showing an operation example of the image forming apparatus according to the third embodiment, and shows a control flow of the control unit when receiving a print job.

[0102] Fig.12 Yes means Fig.10 Flowchart showing the flow of control by the control unit in the first print medium image forming process.

[0103] Fig.13 It means according to Fig.10 Flowchart showing the flow of control by the control unit in the image forming process shown.

[0104] Fig.14 It is a diagram for explaining a schematic configuration of an image forming apparatus according to a fourth embodiment of the present invention.

[0105] Fig.15 It is a perspective view for explaining a cutting mechanism of an image forming apparatus according to a fourth embodiment.

[0106] Fig.16 This is a flowchart showing an operation example of the image forming apparatus according to the fourth embodiment.

[0107] Fig.17 It is a schematic diagram showing an initial position and a cutting completion position of a cutting operation of a cutting mechanism of an image forming apparatus according to a fourth embodiment.

[0108] Fig.18 This is a timing chart for explaining the feeding of the printing medium, the driving of the motor, and the cutting timing of the printing medium controlled by the control unit of the image forming apparatus according to the fourth embodiment.

[0109] Fig.19 It is a diagram for explaining a schematic configuration of an image forming apparatus according to a fifth embodiment of the present invention.

[0110] Fig. 20 This is a flowchart showing an operation example of the image forming apparatus according to the fifth embodiment.

[0111] Fig.21 This is a timing chart for explaining the feeding of the printing medium, the driving of the motor, and the cutting timing of the printing medium controlled by the control unit of the image forming apparatus according to the fifth embodiment. DETAILED DESCRIPTION

[0112] [First embodiment]

[0113] Below, refer to Figure 1 A first embodiment of the present invention will be described. In this embodiment, a laser printer that forms an image on a printing medium S using toner is described as an example of the image forming apparatus 1 .

[0114] [Configuration of Image Forming Apparatus 1]

[0115] Figure 1 FIG. 1 is a diagram for explaining a schematic configuration of an image forming apparatus 1 according to a first embodiment of the present invention. Figure 1 As shown, the vertical direction is defined with the installation surface side as the bottom, based on the state where the image forming apparatus 1 is installed and can be used. Also, the front-rear direction is defined with the side where the discharge tray TR is installed as the front.

[0116] In the following description, a monochrome printer that performs image forming processing of monochrome images is exemplified as the image forming device 1. However, the present invention is not limited thereto, and for example, a color printer that performs image forming processing of full-color images may also be used. In addition, the present invention may also be an MFP (Multi-Function Printer) that has functions other than the image forming function, i.e., the printing function, such as a scanner function, a copy function, or a fax function.

[0117] In the following description, the case where the print medium S is completely divided into two first print mediums and second print mediums in the front and rear in the conveying direction by the cutting mechanism 100 as a processing unit and then cut is exemplified. However, as long as the processing for cutting the print medium S is performed, the present invention is not limited in any way. Specifically, the present invention may also perform a cutting process in contact with a cutter described later of the cutting mechanism 100 in order to cut the print medium S. In addition, the present invention may also perform a crease process in order to cut the print medium S. In addition, the present invention may also perform a perforation process in order to cut the print medium S.

[0118] like Figure 1As shown, the image forming apparatus 1 includes: a main body housing 10, a feed unit 3, an image forming unit 4, a cutting mechanism 100, and a discharge tray TR. In addition, the image forming apparatus 1 includes an intermediate discharge roller 37, a discharge roller 38, a main motor M0, and a control unit C. A storage cover 10A that stores the cutting mechanism 100 is mounted on the main body housing 10 in a manner that it can be opened and closed relative to the main body housing 10. The storage cover 10A is provided with a sensor K7 that detects the open and closed state of the storage cover 10A, and the sensor K7 is configured to output its detection result to the control unit C. In the first embodiment, the main body housing 10 and the storage cover 10A constitute an outer container of the image forming apparatus 1, for example, to store the feed unit 3, the image forming unit 4, the cutting mechanism 100, etc.

[0119] The feed unit 3 supplies the print medium S. The feed unit 3 includes a feed tray 31, a pickup roller 32, a pressing plate 33, a separation roller 34, a feed roller 35, and a registration roller 36. The feed tray 31 is a box-shaped member with an open upper surface, and accommodates a predetermined amount of the print medium S. In addition, the print medium is not limited to paper media such as printing paper, and other media may be resin media made of plastic such as OHP sheets.

[0120] The pickup roller 32 delivers the print medium S stored in the feed tray 31. That is, when delivering the print medium S, the print medium S stored in the feed tray 31 approaches the pickup roller 32 through the pressing plate 33, and is fed to the separation roller 34 as the pickup roller 32 rotates. The separation roller 34 separates the print medium S picked up by the pickup roller 32 one by one. The feed roller 35 delivers the print medium S toward the registration roller 36. The registration roller 36 aligns the position of the top end of the print medium S and then delivers the print medium S toward the image forming unit 4.

[0121] The image forming unit 4 performs an image forming process on the printing medium S fed by the feeding unit 3 to form an image. The image forming unit 4 includes a photosensitive drum 46 and a developing roller 44R that supplies toner to the photosensitive drum 46. The image forming unit 4 also includes a transfer unit 42 that includes a transfer roller that transfers the toner supplied to the photosensitive drum 46 to the printing medium S, and a fixing unit 45 that fixes the toner transferred to the printing medium S on the printing medium S. The image forming unit 4 also includes an exposure unit 41 and a charger 43.

[0122] The exposure unit 41 exposes the photosensitive drum 46 by irradiating a predetermined light beam B indicated by a dashed line in the figure to the photosensitive drum 46. Specifically, the exposure unit 41 includes a laser light source (not shown), a polygon mirror 41G, a scanning lens 41L, a polygon motor 41M, and a reflection mirror 41R.

[0123] The polygon mirror 41G is a rotating polygon mirror with six reflection surfaces formed by the side surfaces of a regular hexagonal prism. The polygon mirror 41G is used to deflect the light beam B emitted by the laser light source toward the photosensitive drum 46. The polygon mirror motor 41M is a motor different from the main motor M0, and drives the polygon mirror 41G to rotate independently of the main motor M0 based on an operation instruction from the control unit C.

[0124] The exposure unit 41 deflects the light beam B by the polygon mirror 41G, and emits the light beam B from the polygon mirror 41G to the surface of the photosensitive drum 46 via the scanning lens 41L and the reflection mirror 41R. The exposure unit 41 scans the surface of the photosensitive drum 46 with the light beam B to expose the photosensitive drum 46. Thus, an electrostatic latent image constituting a toner image described later is formed on the surface of the photosensitive drum 46. The polygon motor 41M is, for example, a brushless DC motor.

[0125] The transfer unit 42 includes a transfer roller sandwiching the printing medium S with the photosensitive drum 46, and transfers the toner image from the photosensitive drum 46 to the printing medium S. The charger 43 includes, for example, a corona charger having a charging line and a grid portion (not shown). In the charger 43, a charging voltage is applied to the charging line and a grid voltage is applied to the grid portion by a high voltage generating circuit (not shown), thereby generating corona discharge, and the surface of the photosensitive drum 46 is uniformly charged.

[0126] Furthermore, for example, the transfer section 42 may include a transfer belt instead of a transfer roller. Furthermore, for example, the charger 43 may include a charging roller instead of a scorotron charger.

[0127] The developing roller 44R is integrally formed with a toner container 44A that contains toner as a developer to form a toner box 44. The toner box 44 is attachable to and detachable from the main body casing 10 through an opening 10B provided on the front side of the main body casing 10.

[0128] The photosensitive drum 46 and the charger 43 are integrally formed into a drum cartridge 47. The drum cartridge 47 can be attached to and detached from the main body casing 10 through the opening 10B. Figure 1 As shown by the double-dashed line in FIG. 1 , a front cover FC capable of opening and closing the opening 10B is provided on the front surface side. When the front cover FC opens the opening 10B, the user can load and unload the toner cartridge 44 or the drum cartridge 47. In addition, a sensor K5 for detecting the opening and closing state of the front cover FC is provided on the front cover FC. The sensor K5 is configured to output the opening and closing state of the front cover FC to the control unit C.

[0129] In addition, the case where the toner cartridge 44 and the drum cartridge 47 are separable from each other is described. However, the present invention is not limited to this, and for example, an integrated process cartridge in which the toner cartridge 44 and the drum cartridge 47 are not separable may be used.

[0130] In the image forming section 4, after the surface of the photosensitive drum 46 is uniformly charged by the charger 43, an electrostatic latent image based on the printing data from the control section C is formed on the surface of the photosensitive drum 46 by the light beam B from the exposure section 41. In addition, the developing roller 44R supplies toner from the inside of the toner box 44 to the surface of the photosensitive drum 46 on which the electrostatic latent image is formed. As a result, the electrostatic latent image is visualized, and a toner image is formed on the surface of the photosensitive drum 46. Thereafter, the printing medium S fed from the feeding section 3 is conveyed to a transfer position located between the photosensitive drum 46 and the transfer section 42, so that the toner image formed on the surface of the photosensitive drum 46 is transferred to the printing medium S.

[0131] The print medium S to which the toner image is transferred is transported to the fixing unit 45 via the photosensitive drum 46 and the transfer unit 42. The fixing unit 45 fixes the toner image formed on the print medium S. Specifically, the fixing unit 45 thermally fixes the toner image on the print medium S transported from the photosensitive drum 46 and the transfer unit 42. The print medium S to which the toner image is thermally fixed is discharged onto the discharge tray TR via the intermediate discharge roller 37 and the discharge roller 38.

[0132] like Figure 1 As shown by the solid line, the discharge tray TR is provided at the exposed portion of the upper surface of the main body housing 10. That is, the discharge tray TR is a storage portion for the print medium S, and is provided at the portion of the upper surface of the main body housing 10 that is not covered by the storage cover 10A. In addition, the discharge tray TR constitutes a first discharge portion for discharging the print medium S that has passed through the fixing portion 45. In addition, the discharge roller 38 is an example of a discharge roller that conveys the print medium S that has passed through the fixing portion 45 toward the first discharge portion.

[0133] The fixing unit 45 includes, for example, a heating roller 45HR, a pressure roller 45PR, and a heater 45H. The heating roller 45HR contacts the printing medium S on which the toner image is formed to heat the printing medium S. The pressure roller 45PR is pressed against the heating roller 45HR side by a pressing portion (not shown). The heater 45H heats the heating roller 45HR. In the fixing unit 45, the toner image on the printing medium S is fixed with a predetermined pressure applied between the heating roller 45HR and the pressure roller 45PR.

[0134] In addition, two heaters 45H are provided inside the heating roller 45HR, for example. The heater 45H is formed by using, for example, a halogen lamp. The heater 45H emits light and generates heat when energized, and heats the heating roller 45HR from the inside by radiant heat.

[0135] Specifically, the control unit C controls the supply current from the energized circuit to the heater 45H by controlling the energized circuit (not shown). Thus, the heating of the heating roller 45HR from the heater 45H is controlled by the control unit C. In addition, the control unit C also controls the rotation drive of the pressure roller 45PR by controlling the main motor M0. Then, in the fixing unit 45, the printing medium S to which the toner image is transferred is conveyed between the heating roller 45HR and the pressure roller 45PR, whereby the toner image is thermally fixed on the printing medium S.

[0136] In addition, the case where the fixing unit 45 having the heating roller 45HR and the pressure roller 45PR is used is described, but the fixing unit 45 of the present invention is not limited to this. For example, a heating unit having a heater having a substrate and a resistive heating element provided on the substrate may be used in the fixing unit instead of the heating roller 45HR. In addition, for example, a pressure pad type fixing unit may be used, which is provided with an endless belt that clamps the printing medium S with the heating roller 45HR and a clamping forming member having a pressure pad that presses the endless belt toward the heating roller 45HR side.

[0137] In addition, the main body housing 10 has a rear opening 10C. The rear opening 10C is provided on the rear surface side of the main body housing 10. Figure 1 As illustrated by the double-dashed line in the figure, the main body housing 10 has a rear cover RC that can open and close the rear opening 10C. The rear cover RC is provided on the rear surface side of the main body housing 10. The rear cover RC constitutes a closing member that closes the rear opening 10C. In addition, the rear cover RC also constitutes a second discharge tray, which serves as a second discharge unit for discharging the print medium S that has passed through the fixing unit 45.

[0138] In other words, the rear cover RC can also close the second discharge tray by closing the rear opening 10C. On the other hand, the rear cover RC can function as a second discharge tray for accommodating the print medium S conveyed by the fixing unit 45 and the intermediate discharge roller 37 by opening the rear opening 10C. As a result, the print medium S that has passed through the fixing unit 45 can be discharged to the second discharge tray without being bent. In addition, the rear cover RC has a sensor K6 for detecting the open and closed state of the rear cover RC. The sensor K6 is configured to output the open and closed state of the rear cover RC to the control unit C.

[0139] The cutting mechanism 100 is disposed downstream of the fixing unit 45 in the conveying direction of the printing medium S. The cutting mechanism 100 is disposed in the third conveying path H3 described later. The cutting mechanism 100 is a well-known cutter mechanism. The cutting mechanism 100 includes a blade 100A and a blade 100B. In addition, the cutting mechanism 100 includes a carriage (not shown) and a carriage motor M1 for driving the carriage. The carriage holds the blade 100A and the blade 100B as cutting blades (cutter). The carriage is configured to be movable in a predetermined direction by the carriage motor M1.

[0140] The carriage motor M1 is a motor different from the main motor M0 . The carriage motor M1 drives the carriage independently of the main motor M0 based on an operation instruction from the control unit C. The carriage motor M1 is, for example, a brushless DC motor.

[0141] Specifically, the carriage is moved in the width direction of the print medium S as a predetermined direction using the rotational force of the carriage motor M1, and the blades 100A and 100B cut the print medium S in the width direction. Thus, the cutting process of the blades 100A and 100B is performed on the print medium S, and the print medium S is completely divided into the first print medium and the second print medium in the conveying direction. The cutting process is an example of a processing process.

[0142] Furthermore, at least one of the blade 100A and the blade 100B is rotated by the carriage motor M1 to move the carriage, thereby moving together with the carriage to perform the cutting process.

[0143] In addition, the cutting mechanism 100 may be configured to include either the blade 100A or the blade 100B.

[0144] In addition, if Figure 1 As shown by the dotted line in , the image forming apparatus 1 includes a conveying path as a space for conveying the printing medium S. Specifically, the image forming apparatus 1 of the first embodiment includes a supply conveying path H0 for conveying the printing medium S from the feed section 3 toward the image forming section 4, and a first conveying path H1 for conveying the printing medium S that has passed through the fixing section 45 toward the discharge tray TR. In addition, the image forming apparatus 1 includes a second conveying path H2 for conveying the printing medium S that has passed through the fixing section 45 and has had an image formed on any one side thereof processed by the image forming section 4 again toward the photosensitive drum 46. In addition, the image forming apparatus 1 includes a third conveying path H3 for conveying the printing medium S that has passed through the fixing section 45 toward the cutting mechanism 100.

[0145] Specifically, in the supply conveying path H0, the location where the pickup roller 32 is provided is the starting location for conveying the printing medium S, and the location where the rear registration sensor K3 described later is provided is the end location for conveying the printing medium S. In addition, as conveying rollers for conveying the printing medium S, for example, a pickup roller 32, a separation roller 34, a feed roller 35, and a registration roller 36 are provided in the supply conveying path H0. These pickup roller 32, the separation roller 34, the feed roller 35, and the registration roller 36 are configured to rotate by the driving force from the main motor M0, for example.

[0146] In addition, in the supply and conveying path H0, a branch path H00 is provided on the front cover FC side. When the front cover FC opens the opening 10B, for example, the user can insert the printing medium S into the branch path H00 by reaching in from the outside of the image forming apparatus 1. Therefore, the user can feed the printing medium S into the supply and conveying path H0 via the branch path H00.

[0147] The supply conveying path H0 includes a tray sensor K1, a front registration sensor K2, and a rear registration sensor K3. The tray sensor K1 is provided near the feed tray 31. The tray sensor K1 detects the presence of the feed tray 31. The tray sensor K1 is configured using, for example, an optical sensor. The tray sensor K1 is configured to output the presence of the feed tray 31 to the control unit C.

[0148] The front registration sensor K2 detects the rear end of the printing medium S. The rear registration sensor K3 detects the front end of the printing medium S. The front registration sensor K2 and the rear registration sensor K3 can each use a sensor having an actuator, a light sensor, or the like, which swings by contacting the printing medium S. The front registration sensor K2 and the rear registration sensor K3 are examples of detection units provided upstream of the image forming unit 4 in the conveying direction. Moreover, the front registration sensor K2 and the rear registration sensor K3 constitute a detection unit capable of detecting the length of the printing medium S in the conveying direction.

[0149] In addition, the front registration sensor K2 and the rear registration sensor K3 output detection results to the control unit C. Specifically, the front registration sensor K2 outputs an ON signal to the control unit C during the period from the timing when the front end of the printing medium S reaches the position of the front registration sensor K2 to the time when the rear end of the printing medium S passes the position of the front registration sensor K2, and the front registration sensor K2 outputs an OFF signal to the control unit C during the period other than that. Similarly, the rear registration sensor K3 outputs an ON signal to the control unit C during the period from the timing when the front end of the printing medium S reaches the position of the rear registration sensor K3 to the time when the rear end of the printing medium S passes the position of the rear registration sensor K3, and the rear registration sensor K3 outputs an OFF signal to the control unit C during the period other than that.

[0150] In the first conveying path H1, the conveying end point of the supply conveying path H0 is the conveying start point of the printing medium S, and the connection part which is provided downstream of the discharge roller 38 in the conveying direction and connected to the discharge tray TR is the conveying end point of the printing medium S. That is, the first conveying path H1 is a conveying path between the installation part of the rear registration sensor K3 and the connection part G4 in the discharge tray TR, and the connection part G4 is an end part which is exposed on the upper surface side of the main body housing 10 and the user can collect the printing medium S. In addition, as a conveying roller for conveying the printing medium S, for example, an intermediate discharge roller 37 and a discharge roller 38 are provided in the first conveying path H1. These intermediate discharge rollers 37 and the discharge rollers 38 are configured to rotate by the driving force from the main motor M0, for example.

[0151] In the first conveying path H1, the sensor K4 is provided between the fixing unit 45 and the intermediate discharge roller 37. The sensor K4 is configured using, for example, a light sensor. The sensor K4 is configured to detect the presence or absence of the printing medium S between the fixing unit 45 and the intermediate discharge roller 37. The sensor K4 is configured to output the presence or absence of the printing medium S to the control unit C. In other words, the sensor K4 detects whether the printing medium S has passed through the fixing unit 45 and notifies the control unit C.

[0152] The conveyance start point of the print medium S in the second conveyance path H2 is a merging point G1 with the first conveyance path H1 . The merging point G1 is provided downstream of the intermediate discharge roller 37 in the conveyance direction.

[0153] On the other hand, the conveyance end point of the print medium S in the second conveyance path H2 is the merging point G3 with the first conveyance path H1. The merging point G3 is different from the merging point G1 and is provided upstream of the registration roller 36 in the conveyance direction.

[0154] As conveying rollers for conveying the printing medium S, a reverse conveying roller 39A and a reverse conveying roller 39B are sequentially provided in the second conveying path H2, for example, along the conveying direction in the second conveying path H2. Then, in the second conveying path H2, the printing medium S cut back from the confluence point G1 by the discharge roller 38 is sequentially conveyed toward the confluence point G3 by the reverse conveying roller 39A and the reverse conveying roller 39B. These reverse conveying rollers 39A and the reverse conveying roller 39B are, for example, configured to rotate by the driving force from the main motor M0.

[0155] In addition, if Figure 1As shown, the second conveying path H2 is a conveying path different from the first conveying path H1 and is provided below the first conveying path H1. In addition, the second conveying path H2 is connected to the first conveying path H1 at the confluence portion G1 and the confluence portion G3, and together with the first conveying path H1, it forms a conveying path for annularly conveying the printing medium S. Thus, in the image forming apparatus 1, in combination with the return of the printing medium S by the discharge roller 38, double-sided printing can be reliably performed.

[0156] The third conveyance path H3 starts conveying the print medium S at a merging point G2 with the first conveyance path H1. The merging point G2 is located upstream of the discharge roller 38 in the conveyance direction.

[0157] On the other hand, the conveyance end point of the print medium S in the third conveyance path H3 is the connection point G4 connected to the discharge tray TR. The connection point G4 is a point different from the merging point G2. The connection point G4 is provided downstream of the discharge roller 38 in the conveyance direction.

[0158] like Figure 1 As shown in FIG. 1 , the third conveying path H3 is a conveying path different from the first conveying path H1 . The third conveying path H3 is provided above the first conveying path H1 .

[0159] In addition, a flap FP is provided near the confluence portion G2 for distributing the print medium S to the first conveying path H1 or the third conveying path H3. In addition, as conveying rollers for conveying the print medium S, an upstream conveying roller 40A and a downstream conveying roller 40B are provided in sequence in the third conveying path H3, for example, with the cutting mechanism 100 interposed therebetween, along the conveying direction in the third conveying path H3.

[0160] The flap FP, the upstream conveying roller 40A, and the downstream conveying roller 40B are configured to be operated by the driving force from the drive motor M2, for example. The drive motor M2 is a motor different from the main motor M0. The drive motor M2 drives the flap FP, the upstream conveying roller 40A, and the downstream conveying roller 40B independently of the main motor M0 based on the operation instruction from the control unit C. The drive motor M2 is, for example, a stepping motor.

[0161] The main motor M0 drives the conveying rollers provided in the supply conveying path H0, the first conveying path H1, and the second conveying path H2, respectively, as described above, based on the operation instruction from the control unit C. In addition, the main motor M0 drives, for example, the photosensitive drum 46, the developing roller 44R, the transfer roller of the transfer unit 42, or the pressure roller 45PR of the fixing unit 45, based on the operation instruction from the control unit C. In other words, the main motor M0 is connected to a transmission mechanism such as a gear that transmits its rotational force, and the main motor M0 functions as a power source for, for example, the conveying rollers and the photosensitive drum 46 included in the image forming unit 4. The main motor M0 is, for example, a brushless DC motor.

[0162] The control unit C includes, for example, a CPU, a RAM, a ROM, and an input / output circuit. The control unit C performs image formation control by performing calculation processing based on the program and data stored in the ROM. In addition, the control unit C also appropriately performs control processing other than image formation control based on information obtained from, for example, the tray sensor K1, the front registration sensor K2, the rear registration sensor K3, and the sensors K4 to K7.

[0163] [Operation Example of Image Forming Apparatus 1]

[0164] See also below Figure 2 An operation example of the image forming apparatus 1 according to the first embodiment will be described in detail. Figure 2 1 is a flowchart showing an example of the operation of the image forming apparatus 1. In the following description, a case where double-sided printing is performed on an A4-sized print medium S is exemplified. In the following description, a case where the print medium S is cut and divided into two A5-sized print media, namely, a first print medium and a second print medium is exemplified.

[0165] like Figure 2 As shown in S1 of FIG. 1 , the control unit C determines whether a print job has been received for the image forming apparatus 1. When the control unit C determines that a print job has not been received (S1: No), the control unit C sets the image forming apparatus 1 to a standby state.

[0166] On the other hand, when the control unit C determines that a print job has been received (S1: Yes), the control unit C determines whether the front cover FC and the rear cover RC are in a closed state (S2). Specifically, the control unit C determines whether the front cover FC has closed the opening 10B based on the detection result of the sensor K5. In addition, the control unit C determines whether the rear cover RC has closed the rear opening 10C and thus the second discharge tray based on the detection result of the sensor K6.

[0167] In the first embodiment, in the determination process of S2 , the control unit C also determines whether the storage cover 10A is in the closed state relative to the main body casing 10 based on the detection result of the sensor K7 .

[0168] If the control unit C determines that the front cover FC, the rear cover RC, and the storage cover 10A are not all closed (S2: No), the control unit C determines that the image forming apparatus 1 is not in an operable state. Next, the control unit C sets the image forming apparatus 1 to a standby state.

[0169] In addition to this description, the control unit C may be configured to operate a notification unit such as a display unit or a sound output unit (not shown) to notify the user that the front cover FC, the rear cover RC, or the storage cover 10A is open or to urge a change to a closed state.

[0170] On the other hand, when the control unit C determines that the front cover FC, the rear cover RC, and the storage cover 10A are all closed (S2: Yes), the control unit C determines that the image forming apparatus 1 is in an operable state. Then, the control unit C can execute the subsequent first image forming process, the second image forming process, and the cutting process.

[0171] In the first embodiment, the control unit C understands the operable state of the image forming apparatus 1. As a result, when the first image forming process, the second image forming process, and the processing process are executed, the possibility of the user inserting his hand into the inside of the main body housing 10 and the storage cover 10A can be greatly reduced. Therefore, in the first embodiment, double-sided printing on the print medium S and processing for cutting the print medium S can be safely performed.

[0172] Next, the control unit C determines whether the length of the printing medium is longer than a prescribed length (S3). Specifically, the control unit C performs a detection process for detecting the length of the printing medium S conveyed in the supply conveying path H0 in the conveying direction based on the detection result of the detection unit, such as the rear registration sensor K3. Then, when the control unit C determines that the length of the printing medium S is less than a prescribed length (for example, the prescribed length of the A4 size minus 10 mm) (S3: No), the control unit C determines that the printing medium S is not of the A4 size. After that, the control unit C determines that the printing operation cannot be properly performed, and performs an abnormal notification indicating that the printing operation cannot be performed through a notification unit (not shown) (S4), and ends the process.

[0173] On the other hand, when the control unit C determines that the length of the print medium S is greater than the predetermined length (S3: Yes), the control unit C determines that the print medium S is of A4 size. After that, the control unit C determines that the printing job can be properly executed and ends the detection process. By using such a detection process, the length of the transported print medium S can be acquired. Thus, in the first embodiment, based on the acquired print medium length, the first image forming process, the second image forming process, and the processing process can be executed with high accuracy for the print medium S. As a result, in the first embodiment, the printing accuracy of the print medium S on which the processing process is executed can be improved.

[0174] In addition, the control unit C may also be configured to perform detection processing using the detection result of the front registration sensor K2, for example. In addition, in the first embodiment, the control unit C uses the detection result of the front registration sensor K2 and the registration roller 36 to correct the inclination of the print medium S relative to the conveying direction before the processing of S3.

[0175] Specifically, the control unit C obtains the deviation amount of the detection time of one end and the other end of the printing medium S in the width direction of the printing medium S by using the detection result of the front registration sensor K2. In detail, the control unit C obtains the difference between the detection time of one end and the detection time of the other end as the deviation amount, and obtains the difference time corresponding to the magnitude of the inclination of the printing medium S. Then, the control unit C corrects the inclination of the top end of the printing medium S by making the top end of the printing medium S collide with the registration roller 36 during the obtained difference time, thereby stopping the conveyance of the printing medium S. Thereafter, when the control unit C determines that the obtained difference time has passed, it determines that the inclination of the top end of the printing medium S has been corrected, and performs re-conveying of the printing medium S using the registration roller 36.

[0176] Next, the control unit C determines whether the number of pages of the print data is greater than or equal to 2 pages and less than 4L pages (S5). L, which indicates the number of pages of the print data, is an integer greater than or equal to 1, and the control unit C obtains L, which indicates the number of pages of the print data, from the received print job. When the control unit C determines that the number of pages is not greater than or equal to 2 pages and less than 4L pages (S5: No), the control unit C sequentially executes a series of processes following the subsequent part A.

[0177] On the other hand, when the control unit C determines that the number of pages is 2 or more and less than 4L pages ( S5 : Yes), the control unit C executes a first image forming process for forming an image on one surface of the print medium S by the image forming unit 4 ( S6 ).

[0178] Next, the control unit C executes a reverse conveying process (S7) of switching the print medium S from the first conveying path H1 back to the second conveying path H2 by the discharge roller 38. Next, the control unit C executes a second image forming process (S8) of forming an image on the other side of the print medium S by the image forming unit 4.

[0179] As described above, by executing the reverse conveying process by the control unit C, the print medium S can be conveyed to the first conveying path H1 and the second conveying path H2 in sequence. Thus, in the first embodiment, more reliable double-sided printing can be performed on the print medium S. In other words, the printing process is performed on the front side of the print medium S by the first image forming process. In addition, the printing process is performed on the back side of the print medium S by the second image forming process. In addition, the front side of the print medium S is an example of one side of the print medium S. In addition, the back side of the print medium S is an example of another side of the print medium S.

[0180] In addition, the present invention first performs a printing process on the back side of the print medium S by the first image printing process. Thereafter, the present invention can also be applied to double-sided printing in which a printing process is performed on the front side of the print medium S by the second image printing process. In this case, the back side of the print medium S is an example of one side of the print medium S. In addition, the front side of the print medium S is an example of the other side of the print medium S.

[0181] In addition, in the first embodiment, in the first image forming process and the second image forming process, the control unit C drives the photosensitive drum 46, the developing roller 44R, the transfer unit 42, or the fixing unit 45 by controlling the main motor M0. Therefore, in the first embodiment, the first image forming process and the second image forming process for the printing medium S can be performed with high accuracy. As a result, in the first embodiment, the printing accuracy of the double-sided printing for the printing medium S can be improved.

[0182] In addition, in the first embodiment, the control unit C drives the polygonal mirror motor 41M independently of the main motor M0 in the first image forming process and the second image forming process. Thus, in the first embodiment, the exposure unit 41 can appropriately expose the photosensitive drum 46. Therefore, in the first embodiment, the image quality of double-sided printing of the printing medium S can be easily improved.

[0183] Furthermore, in the first embodiment, the control unit C sets the fixing temperature of the fixing unit 45 and the transfer bias of the transfer unit 42 to different values ​​in the first image forming process and the second image forming process.

[0184] Specifically, the control unit C controls the temperature of the heater 45H so that the fixing target temperature in the first image forming process becomes a temperature higher than the fixing target temperature in the second image forming process. Thus, when the second image forming process is performed, the control unit C can use a more appropriate fixing temperature for the print medium S heated by the first image forming process and perform the fixing process of the fixing unit 45. As a result, in the first embodiment, the printing accuracy of the double-sided printing on the print medium S can be improved.

[0185] In addition, the control unit C controls the transfer unit 42 so that the transfer bias applied to the transfer roller in the first image forming process becomes a lower value than the transfer bias in the second image forming process. Thus, when the control unit C performs the second image forming process, the transfer unit 42 can perform the transfer process using a more appropriate transfer bias for the print medium S whose surface water evaporation resistance value increases due to the first image forming process. As a result, in the first embodiment, the printing accuracy of the double-sided printing on the print medium S can be improved.

[0186] Furthermore, in the first embodiment, the control unit C can adjust the collision time of the print medium S with the registration roller 36. In other words, the control unit C can adjust the stop time of the print medium S that stops due to the contact with the registration roller 36. However, in the case of a monochrome printer as in the first embodiment, the control unit C adjusts the stop time in the first image forming process and the stop time in the second image forming process to the same value. Thus, in the first embodiment, the printing accuracy of the double-sided printing on the print medium S can be improved.

[0187] On the other hand, unlike the first embodiment, in the case of a color printer having a plurality of color process cartridges, the control unit C controls the registration roller 36 so that the stop time in the first image forming process is longer than the stop time in the second image forming process. Thus, when the second image forming process is performed, the control unit C can perform the image forming process of the plurality of color process cartridges at a more appropriate conveying speed for the print medium S having a faster conveying speed than the first image forming process. Thus, in the first embodiment, the printing accuracy of the double-sided printing on the print medium S can be improved.

[0188] Next, the control unit C executes a cutting process (S9) for cutting the print medium S by the cutting mechanism 100. In other words, the control unit C cuts the A4-size print medium S into an A5-size first print medium and an A5-size second print medium.

[0189] In addition, when the control unit C executes the cutting process, the control unit C drives the carriage motor M1 after stopping the main motor M0. In this way, in the first embodiment, the control unit C drives the carriage motor M1 different from the main motor M0 when executing the cutting process, so that the cutting process using the cutting mechanism 100 can be independently executed. Therefore, in the first embodiment, the cutting process can be appropriately performed. Further, in the first embodiment, the control unit C stops the main motor M0 when executing the cutting process, so that the cutting process using the cutting mechanism 100 can be more reliably and independently executed. Therefore, in the first embodiment, the cutting process can be more appropriately performed.

[0190] Furthermore, when the control unit C executes the shutoff process, the control unit C stops the heater 45H. Thus, in the first embodiment, it is possible to easily achieve power saving of the image forming apparatus 1 .

[0191] Next, the control unit C executes a discharge process of discharging the A5-size first print medium and the A5-size second print medium to the discharge tray TR by the upstream transport roller 40A and the downstream transport roller 40B ( S10 ).

[0192] Then, also refer to Figures 3 to 7 , for the next Figure 2 A series of processing in the section A shown will be described in detail. Figure 3 is a flowchart showing an example of the operation of the image forming apparatus 1. Figure 2 The operation example of part A is shown. Figure 4 is a flowchart showing an example of the operation of the image forming apparatus 1. Figure 3 A specific operation example of S12 is shown.

[0193] Figure 5 is a flowchart showing an example of the operation of the image forming apparatus 1. Figure 3 A specific operation example of S16 is shown. Figure 6 is a flowchart showing an example of the operation of the image forming apparatus 1. Figure 3 A specific operation example of S17 is shown. Figure 7 is a flowchart showing an example of the operation of the image forming apparatus 1. Figure 3 The specific operation example of S18 shown in FIG. Figure 4 to Figure 7 In the above description, the subroutines including the processing of S3 and the processing of S4 are collectively recorded in the detection processing SB, and the detailed description of the detection processing SB is omitted.

[0194] like Figure 3 As shown in S11, the control unit C determines whether the number of pages of the print data is 4L pages, (4L+1) pages, (4L+2) pages, or (4L+3) pages. If the control unit C determines that the number of pages of the print data is 4L pages, (4L+1) pages, (4L+2) pages, and (4L+3) pages, the control unit C executes the printing process of 4L pages shown in S12, S13, S14, and S15, respectively. In addition, in each process of S12, S13, S14, and S15, the number of pages of the print data is the same as the number of 4L pages, and therefore, the control unit C performs the same control action on each part of the image forming apparatus 1. Figure 4 The specific operations of each of the processes of S12 , S13 , S14 , and S15 will be described later.

[0195] In addition, the 4L pages described here refer to, for example, the number of pages of the front side and the back side of the A4-sized print medium S and the front side and the back side of the same print medium S. That is, when the number of pages of print data is 4L pages, images are formed on the front side (front side and back side) and the back side (front side and back side) of the A4-sized print medium S, respectively.

[0196] In addition, (4L+α) pages means that in addition to the printing process of 4L pages, the printing process of the number of pages α is performed on the A5-sized printing area of ​​the A4-sized printing medium. In other words, the control unit C performs the printing process of (4L+α) pages on the A5-sized printing medium. In addition, as described above, the number of pages α can be any number from 0 to 3.

[0197] After that, when the control unit C determines that the number of pages of the print data is 4L pages, it determines that the image forming process in the received print job is completed by executing the process of S12, and ends the process. In addition, when the control unit C determines that the number of pages of the print data is (4L+1) pages, after executing the process of S13, it executes the printing process of the last page on the subsequent print medium S different from the print medium S on which the image of 4L pages is formed (S16).

[0198] Furthermore, when the control unit C determines that the number of pages of the print data is (4L+2), after executing the process of S14, the control unit C executes the print process of the last two pages on the subsequent print medium S different from the print medium S on which the image of the 4L pages is formed (S17). Furthermore, when the control unit C determines that the number of pages of the print data is (4L+3), after executing the process of S15, the control unit C executes the print process of the last three pages on the subsequent print medium S different from the print medium S on which the image of the 4L pages is formed (S18).

[0199] In addition, when the control unit C executes the printing process of 4L pages in S12, S13, S14 or S15, as shown in FIG. Figure 4 As shown in S21 of FIG. 1 , the control unit C initializes the count value M stored in the RAM to a value of "0". Next, the control unit C executes the subroutine of the detection process SB for each print medium S. Then, when the control unit C determines in the detection process SB that the print medium S is A4 size (S3: Yes), the control unit C determines whether the count value M is consistent with the value of L indicating the number of pages (S22). When the control unit C determines that the count value M is consistent with the value of L indicating the number of pages (S22: Yes), the control unit C determines that the printing process of 4L pages for the print medium S is completed and ends the process.

[0200] On the other hand, when the control unit C determines that the count value M does not match the value L indicating the number of pages (S22: No), the control unit C prints and fixes the print data of (4M+4) pages and (4M+2) pages on the first half and the second half of the print medium S, respectively (S23). In other words, the control unit C performs the first image forming process on one side of the A4-sized print medium S. As a result, the A5-sized second print medium and the A5-sized first print medium included in the print medium S are printed with the print data of (4M+4) pages and (4M+2) pages, respectively.

[0201] Next, the control unit C drives the upstream conveying roller 40A and the discharge roller 38 to switch back the print medium S and convey it from the first conveying path H1 to the second conveying path H2 ( S24 ). In other words, the control unit C performs reverse conveying processing on the print medium S.

[0202] Next, the control unit C prints and fixes the print data of (4M+1) pages and (4M+3) pages on the front half and the rear half of the print medium S, respectively (S25). In other words, the control unit C performs the second image forming process on the other side of the A4-sized print medium S. As a result, the first A5-sized print medium and the second A5-sized print medium included in the print medium S respectively print the print data of (4M+1) pages and (4M+3) pages. Therefore, the print data of (4M+1) pages and (4M+2) pages are printed on both sides of the first A5-sized print medium. In addition, the print data of (4M+3) pages and (4M+4) pages are printed on both sides of the second A5-sized print medium.

[0203] Next, the control unit C executes a cutting process (S26) for performing a process for cutting by the cutting mechanism 100. In other words, the control unit C cuts the A4-size print medium S into an A5-size first print medium and an A5-size second print medium.

[0204] In addition, when the control unit C receives a print job for a plurality of print media S, if the first image forming process is executed on the second print medium S while the cutting process is executed on the first print medium S, the polygonal mirror motor 41M is continuously driven. Thus, in the first embodiment, the control unit C continues to drive the polygonal mirror motor 41M when the processes are continuously executed on the first print medium S and the second print medium S. Thus, in the second embodiment, even when the processes are continuously executed on the first print medium S and the second print medium S, the reduction in the processing capacity of the image forming apparatus 1 can be greatly suppressed.

[0205] In addition, when receiving a print job for a plurality of print media S, the control unit C stops the polygonal mirror motor 41M if the first image forming process is not executed on the second print medium S when the first print medium S is cut. Thus, in the present embodiment, the control unit C stops the polygonal mirror motor 41M when it is determined that the first image forming process is not executed after the cutting process. Thus, in the present first embodiment, power saving of the image forming apparatus 1 can be easily achieved.

[0206] Next, the control unit C executes the discharge process (S27) of discharging the first print medium of A5 size and the second print medium of A5 size to the discharge tray TR through the upstream conveying roller 40A, the discharge roller 38, and the downstream conveying roller 40B. After that, the control unit C increments the value of the count value M by 1 (S28) and enters the detection process SB.

[0207] In addition, when the control unit C executes the printing process of the last page of S16, Figure 5 As shown, the control unit C executes the subroutine of the detection process SB. Then, when the control unit C determines that the print medium S is of A4 size in the detection process SB (S3: Yes), the control unit C prints and fixes the print data of (4M+1) pages on the front half of the print medium S (S31). In other words, the control unit C executes the third image forming process of forming the image of the final page on the other side of the A4-sized print medium S through the image forming unit 4.

[0208] Next, the control unit C does not perform the reverse conveying process on the print medium S after the third image forming process, but performs the cutting process (S32) for performing the processing for cutting by the cutting mechanism 100. In other words, the control unit C cuts the A4-sized print medium S into the first A5-sized print medium and the second A5-sized print medium.

[0209] Next, the control unit C executes a discharge process of discharging the A5-size first print medium and the A5-size second print medium to the discharge tray TR by the upstream transport roller 40A, the discharge roller 38 , and the downstream transport roller 40B ( S33 ).

[0210] In addition, although the case where the third image forming process is performed in the printing process of the last page is described, the present invention is not limited to this. For example, in a case where the printing job contains (4N+1) pages (N is an integer greater than 0) of printing data, the control unit C determines that the printing data for the printing medium S that has not been cut is the printing data of the last page. Then, the control unit C performs the third image forming process on any side of the printing medium S with the printing data of the last page. In such a second embodiment, the control unit C omits the reverse conveying process when the number of remaining pages of the printing data is one page. As a result, in the first embodiment, the processing capacity of the image forming device 1 can be improved.

[0211] In addition, when the control unit C executes the printing process of the last two pages of S17, Figure 6 As shown, the control unit C executes the subroutine of the detection process SB for each print medium S. Then, when the control unit C determines that the print medium S is A4 size in the detection process SB (S3: Yes), the control unit C prints and fixes the print data of (4M+2) pages on the rear half of the print medium S (S41). In other words, the control unit C executes the first image forming process on one side of the A4 size print medium S. As a result, the first print medium of A5 size included in the print medium S is printed with the print data of (4M+2) pages.

[0212] Next, the control unit C drives the upstream conveying roller 40A and the discharge roller 38 to switch back the print medium S and convey it from the first conveying path H1 to the second conveying path H2 ( S42 ). In other words, the control unit C performs reverse conveying processing on the print medium S.

[0213] Next, the control unit C prints and fixes the print data of (4M+1) pages on the front half of the print medium S (S43). In other words, the control unit C performs the second image forming process on the other side of the A4-sized print medium S. As a result, the print data of (4M+1) pages is printed on the first print medium of A5 size included in the print medium S. Therefore, the print data of (4M+1) pages and the print data of (4M+2) pages are printed on both sides of the first print medium of A5 size.

[0214] Next, the control unit C executes a cutting process (S44) for performing a process for cutting by the cutting mechanism 100. In other words, the control unit C cuts the A4-size print medium S into an A5-size first print medium and an A5-size second print medium.

[0215] Next, the control unit C executes a discharge process of discharging the A5-size first print medium and the A5-size second print medium to the discharge tray TR by the upstream transport roller 40A, the discharge roller 38 , and the downstream transport roller 40B ( S45 ).

[0216] In addition, when the control unit C executes the printing process of the last three pages of S18, Figure 7 As shown, the control unit C executes the subroutine of the detection process SB for each print medium S. Then, when the control unit C determines that the print medium S is A4 size in the detection process SB (S3: Yes), the control unit C prints and fixes (S51) the print data of (4M+2) pages on the second half of the print medium S. In other words, the control unit C executes the first image forming process on one side of the A4 size print medium S. As a result, the first print medium of A5 size included in the print medium S is printed with the print data of (4M+2) pages.

[0217] Next, the control unit C drives the upstream conveying roller 40A and the discharge roller 38 to switch back the print medium S and convey it from the first conveying path H1 to the second conveying path H2 ( S52 ). In other words, the control unit C performs reverse conveying processing on the print medium S.

[0218] Next, the control unit C prints and fixes the print data of (4M+1) pages and (4M+3) pages on the front half and the rear half of the print medium S, respectively (S53). In other words, the control unit C performs the second image forming process on the other side of the A4-sized print medium S. As a result, the first A5-sized print medium and the second A5-sized print medium included in the print medium S respectively print the print data of (4M+1) pages and (4M+3) pages. Therefore, the print data of (4M+1) pages and (4M+2) pages are printed on both sides of the first A5-sized print medium. In addition, the print data of (4M+3) pages is printed on one side of the second A5-sized print medium.

[0219] Next, the control unit C executes a cutting process (S54) for performing a process for cutting by the cutting mechanism 100. In other words, the control unit C cuts the A4-size print medium S into an A5-size first print medium and an A5-size second print medium.

[0220] Next, the control unit C executes a discharge process of discharging the A5-size first print medium and the A5-size second print medium to the discharge tray TR by the upstream transport roller 40A, the discharge roller 38 , and the downstream transport roller 40B ( S55 ).

[0221] As described above, in the image forming apparatus 1 of the first embodiment, an image is formed on one side of the print medium S by the first image forming process. In addition, an image is formed on the other side of the print medium S by the second image forming process. In addition, by the cutting process, a process for cutting is performed on the print medium S. Thus, in the first embodiment, it is possible to configure the image forming apparatus 1 capable of performing a process for cutting the print medium S on which double-sided printing is performed.

[0222] In addition, in the image forming apparatus 1 of the first embodiment, the cutting mechanism 100 is provided in the third conveying path H3. Therefore, in the present embodiment, the cutting mechanism 100 provided in the third conveying path H3 can be conveyed to the printing medium S separately from the first conveying path H1. In addition, the upstream conveying roller 40A and the downstream conveying roller 40B are driven by a driving motor M2 different from the main motor M0. Therefore, in the present first embodiment, the upstream conveying roller 40A and the downstream conveying roller 40B can be driven finely for the cutting mechanism 100, and the printing medium S can be conveyed with high precision. Therefore, in the present first embodiment, the cutting position of the cutting mechanism 100 in the printing medium S can be adjusted with high precision to perform the cutting process.

[0223] [Second embodiment]

[0224] Next, based on Figure 8 Next, an image forming apparatus 111 according to a second embodiment will be described. In order to facilitate the description, components having the same functions as those described in the first embodiment are denoted by the same reference numerals, and their description will not be repeated. Figure 8 It is a diagram for explaining a schematic configuration of an image forming apparatus 111 according to a second embodiment of the present invention.

[0225] The image forming apparatus 111 according to the second embodiment is different in that the storage cover 10A, the sensor K7 , the third conveyance path H3 , the flap FP, and the drive motor M2 are not provided, and the cutting mechanism 100 is provided in the first conveyance path H1 .

[0226] [Configuration of Image Forming Device 111]

[0227] Specifically, if Figure 8 As shown, in the image forming apparatus 111 according to the second embodiment, the cutting mechanism 100 is provided in the first conveying path H1, for example, between the discharge roller 38 and the downstream conveying roller 40B. In addition, in the image forming apparatus 111, unlike the image forming apparatus 1 according to the first embodiment, the upstream conveying roller 40A is provided in the first conveying path H1 upstream of the discharge roller 38.

[0228] Therefore, as conveying rollers for conveying the print medium S, for example, an intermediate discharge roller 37, an upstream conveying roller 40A, a discharge roller 38, and a downstream conveying roller 40B are provided in the first conveying path H1. In addition, in the image forming apparatus 111, unlike the image forming apparatus 1 according to the first embodiment, the intermediate discharge roller 37, the upstream conveying roller 40A, the discharge roller 38, and the downstream conveying roller 40B are driven by, for example, a driving force from a main motor M0.

[0229] The above configuration provides the image forming apparatus 111 according to the second embodiment with the same effects as those of the image forming apparatus 1 according to the first embodiment. In addition, in the image forming apparatus 111 according to the second embodiment, the cutting mechanism 100 is provided on the first conveying path H1. Thus, in the image forming apparatus 111 according to the second embodiment, it is possible to omit the provision of a dedicated conveying path or the like for guiding the print medium S to the cutting mechanism 100. As a result, in the image forming apparatus 111 according to the second embodiment, it is possible to easily achieve miniaturization of the image forming apparatus 111.

[0230] [Third embodiment]

[0231] Next, based on Figure 8 to Figure 13 Next, an image forming apparatus 121 according to the third embodiment will be described. In addition, for convenience of description, components having the same functions as those described in the first and second embodiments are denoted by the same reference numerals, and their description will not be repeated. Figure 8 This is a diagram for explaining a schematic configuration of an image forming apparatus 121 according to a third embodiment of the present invention.

[0232] [Configuration of Image Forming Device 121]

[0233] The sensor K4 included in the image forming apparatus 121 according to the third embodiment is a paper discharge sensor K4 that detects the presence or absence of the printing medium S. Then, the control unit C also appropriately executes control processing other than image formation control based on information obtained from, for example, the tray sensor K1, the front registration sensor K2, the rear registration sensor K3, the paper discharge sensor K4, and the sensors K5 to K7. The paper discharge sensor K4 is an example of a detection unit.

[0234] The conveyance start point of the printing medium S of the second conveying path H2 is the confluence point G1 with the first conveying path H1. The confluence point G1 is set downstream of the conveyance direction of the intermediate discharge roller 37. On the other hand, the conveyance end point of the printing medium S of the second conveying path H2 is the confluence point G3 with the first conveying path H1. The confluence point G3 is a point different from the confluence point G1. The confluence point G3 is set upstream of the conveyance direction of the registration roller 36.

[0235] The second conveying path H2 is configured such that the print medium S cut back from the confluence point G1 by the discharge roller 38 is sequentially conveyed toward the confluence point G3 by the reverse conveying roller 39A and the reverse conveying roller 39B. In addition, in the second conveying path H2, the first print medium is held by the reverse conveying roller 39A and the reverse conveying roller 39B. The distance between the reverse conveying roller 39A and the reverse conveying roller 39B in the conveying direction in the second conveying path H2 is a distance capable of holding the first print medium of A5 size.

[0236] [Operation Example of Image Forming Device 121]

[0237] Below, refer to Figures 9 to 13 , an operation example of the image forming apparatus 121 according to the third embodiment will be described in detail. Fig. 9 1 is a flowchart showing an example of the operation of the image forming apparatus 121 , and shows the flow of control by the control unit C during the initialization process. Fig.10 and Fig.11 This is a flowchart showing an example of the operation of the image forming apparatus, and shows the flow of control by the control unit when receiving a print job. Fig.12 Yes means Fig.10 Flowchart of the control flow of the control unit C in the first print medium image forming process (S112) shown. Fig.13 Yes means Fig.10 1 is a flowchart of the flow of control by the control unit C in the image forming process (S119) shown.

[0238] Reference Fig. 9 , the control flow of the control unit C during the initialization process is described. Fig. 9 As shown, first, when the power of the image forming apparatus 1 is turned on, the control unit C performs initialization processing (S100) of the image forming apparatus 1. In step S100, based on the control of the control unit C, the operation of the conveying roller, the operation of the image forming unit, and other operations of the image forming apparatus 1 are confirmed by driving the main motor M0.

[0239] Next, the control device C determines whether the rear registration sensor K3 is on (S101). The first printing medium held in the second conveying path H2 is conveyed from the second conveying path H2 to the first conveying path H1 by the drive of the main motor M0 in step S100. The rear registration sensor K3 detects the front end of the first printing medium conveyed to the first conveying path H1 by the processing of step S100. In addition, in step S101, the passage of the first printing medium can be determined based on the detection result of the front registration sensor K2, or the detection result of the front registration sensor K2 and the detection result of the rear registration sensor K3 can be combined to determine the passage of the first printing medium.

[0240] When the rear registration sensor K3 is not ON (S101: No), the control unit C executes step S105 described later. When the rear registration sensor K3 is ON (S101: Yes), the control unit C controls the heater 45H of the fixing unit 45 to set the temperature of the heating roller 45HR of the fixing unit 45 to the temperature α (S102). Here, the temperature α is a temperature lower than the temperature β of the heating roller 45HR in the image forming process described later. The control unit C sets the temperature of the heating roller 45HR to the temperature α by reducing the supply current to the heater 45H or stopping the heater 45H. As an example, the temperature α is a target temperature of 130 degrees Celsius. As an example, the temperature β is a target temperature of 180 degrees Celsius.

[0241] Next, the control unit C determines whether the paper discharge of the first print medium is completed (S103). When the paper discharge of the first print medium is completed (S103: Yes), the control unit C sets the number of times N that the first print medium passes through the fixing unit 45 to 0 (zero) (S104). Here, the number of times N that the first print medium passes through the fixing unit 45 also includes the number of times the print medium S passes through the fixing unit 45 before being cut by the cutting mechanism 100. That is, the case where the portion of the print medium S corresponding to the first print medium before being cut passes through the fixing unit 45 is taken into account.

[0242] In the following description, the number of times N that the first print medium passes through the fixing unit 45 is sometimes simply referred to as "number of times N". In the third embodiment, the number of times the first print medium passes through the paper discharge sensor K4 is referred to as the number of times N. The number of times the first print medium passes through the paper discharge sensor K4 is an example of the number of times N that the first print medium passes through the fixing unit 45.

[0243] Next, the control unit C determines whether the initialization process is completed (S105). If the initialization process is not completed (S105: No), the control unit C executes step S101. If the initialization process is completed (S105: Yes), the control unit C ends the process.

[0244] Next, refer to Figure 10 to Figure 13 , the control flow of the control unit C when receiving a printing job is described. Fig.10 As shown, first, when receiving a print job, the control unit C determines whether the size of the print medium designated by the print data of the print job is greater than or equal to the size of the print medium S accommodated in the feed tray 31 ( S110 ).

[0245] When the size of the print medium specified by the print data is larger than the size of the print medium S accommodated in the feed tray 31 (S110: Yes), the control unit C executes step S119 described later. When the size of the print medium specified by the print data is not larger than the size of the print medium S accommodated in the feed tray 31 (S110: No), the control unit C determines whether the second conveying path H2 holds the first print medium (S111). When the second conveying path H2 does not hold the first print medium (S111: No), the control unit C executes step S119 described later. When the second conveying path H2 holds the first print medium (S111: Yes), the control unit C executes the first print medium image forming process (S112).

[0246] Reference Fig.12 , the first print medium image forming process (S112) is described. In the first print medium image forming process (S112), first, the control unit C determines whether the size of the first print medium is appropriate (S140). In step S140, the control unit C determines whether the print data of the print job is data that can be printed on the first print medium.

[0247] Furthermore, in step S140, the control unit C determines whether the size of the first print medium is appropriate based on the size of the print medium S stored in the storage area of ​​the control unit C. The size of the print medium S stored in the storage area of ​​the control unit C may be the size of the print medium S detected based on the detection results of the front registration sensor K2 and the rear registration sensor K3, or may be a default value size corresponding to the feed tray 3131.

[0248] If the size of the first print medium is not appropriate (S140: No), the control unit C ends the first print medium image forming process without forming an image on the first print medium (S112). If the size of the first print medium is appropriate (S140: Yes), the control unit C determines whether the printing specified by the print job is double-sided printing (S141).

[0249] If the printing is not double-sided (S141: No), the control unit C adds 2 to the number of times N that the first printing medium passes through the fixing unit 45 (S142). If the printing is double-sided (S141: Yes), the control unit C adds 3 to the number of times N that the first printing medium passes through the fixing unit 45 (S143). In steps S142 and S143, the value added to the number of times N by the control unit C is an estimated value that the first printing medium passes through the fixing unit 45 when the image forming process is performed on the first printing medium. The conveyance of the first printing medium will be described later, but in the case of single-sided printing, the first printing medium passes through the fixing unit 45 twice. In addition, in the case of double-sided printing, the first printing medium passes through the fixing unit 45 three times.

[0250] In addition, in step S142 and step S143, an estimated value that the first printing medium passes through the fixing unit 45 when the temperature of the heating roller 45HR of the fixing unit 45 is the temperature β may be added. In this case, the control unit C adds +1 to the number N in step S142 and adds +2 to the number N in step S143. In this case, the threshold value γ in step S143 described later is γ=3.

[0251] After step S142 and step S143, the control unit C determines whether the number of times N that the first print medium has passed through the fixing unit 45 is greater than a threshold value γ (S144). Step S144 is a process for determining whether to perform a re-reversal process described later on the first print medium based on information indicating the number of times the first print medium has passed through the fixing unit 45. Step S144 is equivalent to a determination process. As an example, the threshold value γ is γ=4.

[0252] When the number of times N is greater than the threshold value γ (S144: Yes), the control unit C ends the first print medium image forming process (S112) without forming an image on the first print medium. That is, in this case, the control unit C does not perform the re-inversion process described later. When the number of times N is not greater than the threshold value γ (S144: No), the control unit C sets the temperature of the heating roller 45HR of the fixing unit 45 to the temperature α (S145).

[0253] Next, the control unit C conveys the first printing medium to the first conveying path H1 (S146). In step S146, the control unit C controls the main motor M0 to operate the conveying roller, and conveys the first printing medium to the first conveying path H1 via the supply conveying path H0. After step S146, the control unit C determines whether the first printing medium has passed the paper discharge sensor K4 (S147).

[0254] If the first printing medium does not pass the paper discharge sensor K4 (S147: No), the control unit C repeats step S147. If the first printing medium passes the paper discharge sensor K4 (S147: Yes), the control unit C conveys the first printing medium to the second conveying path H2 (S148). In step S148, the control unit C controls the main motor M0 to switch the first printing medium back from the first conveying path H1 through the discharge roller 38 and the upstream conveying roller 40A and convey it to the second conveying path H2.

[0255] Next, the control unit C sets the temperature of the heating roller 45HR of the fixing unit 45 to the temperature β (S149). After step S149, the control unit C controls the main motor M0 to convey the first printing medium conveyed to the second conveying path H2 to the first conveying path H1 (S150). The processing in steps S145 to S150 is equivalent to the re-reversal processing. In addition, step S149 can also be omitted from the re-reversal processing. In this case, the control unit C executes step S149 after step S150.

[0256] After step S150, the control unit C controls the image forming unit 4 to form an image on the front side of the first printing medium (S151). The front side of the first printing medium corresponds to the front side of the printing medium S. The back side of the first printing medium corresponds to the back side of the printing medium S. Next, the control unit C determines whether the printing specified by the print job is double-sided printing (S152).

[0257] If it is not double-sided printing (S152: No), the control unit C discharges the first print medium to the discharge tray TR (S153). After step S153, the control unit C sets the number of times N that the first print medium has passed through the fixing unit 45 to 0 (zero) (S154). After step S154, the control unit C ends the first print medium image forming process (S112).

[0258] In the case of double-sided printing (S152: Yes), the control unit C executes step S155. Step S155 is the same step as step S147. In the case of No in step S155, the control unit C repeatedly executes step S155. In the case of Yes in step S155, the control unit C sequentially executes steps S156 and S157. Step S156 is the same process as step S148, and step S157 is the same process as step S150. After step S157, the control unit C controls the image forming unit 4 to form an image on the back side of the first printing medium (S158). After step S158, the control unit C executes step S153.

[0259] return Fig.10 Then, the control unit C determines whether there is a next page to be printed (S113). If there is no next page to be printed (S113: No), the control unit C ends the processing when receiving the print job. If there is a next page to be printed (S113: Yes), the control unit C determines whether the printing specified by the print job is double-sided printing (S114). If it is not double-sided printing (S114: No), the control unit C executes step S119 described later. If it is double-sided printing (S114: Yes), the control unit C determines whether the second conveying path H2 holds the first printing medium (S115).

[0260] If the second conveying path H2 does not hold the first print medium (S115: No), the control unit C executes step S119 described later. If the second conveying path H2 holds the first print medium (S115: Yes), the control unit C sets the temperature of the heating roller 45HR of the fixing unit 45 to the temperature α (S116). The case where the answer is Yes in step S115 is the following: (i) the print data included in the print job is not suitable for the size of the first print medium; (ii) the number of times N exceeds the threshold value according to step S144.

[0261] After step S116, the control unit C discharges the first print medium held in the second conveying path H2 to the discharge tray TR (S117). In step S117, the control unit C discharges the first print medium held in the second conveying path H2 to the discharge tray TR without forming an image on the first print medium held in the second conveying path H2 by the image forming unit 4. Steps S115 to S117 correspond to the second discharge process. After step S117, the control unit C sets the number of times N that the first print medium has passed through the fixing unit 45 to 0 (zero) (S118).

[0262] Next, the control unit C executes image forming processing (S119). Fig.13 , the image forming process (S119) is described. Fig.13 As shown, in the image forming process (S119), first, the control unit C sets the temperature of the heating roller of the fixing unit 45 to the temperature β (S160). Then, the control unit C controls the main motor M0 to transport the print medium S stored in the feed tray 31 to the first transport path H1 via the supply transport path H0 (S161).

[0263] After step S161, the control unit C controls the image forming unit 4 to form an image on the front side of the print medium S (S162). Step S162 corresponds to the first image forming process. The front side of the print medium S is an example of one side of the print medium S. The back side of the print medium S is an example of another side of the print medium S.

[0264] Next, the control unit C determines whether the printing specified by the print job is double-sided printing (S163). If it is not double-sided printing (S163: No), the control unit C ends the image forming process (S119). If it is double-sided printing (S163: Yes), the control unit C transports the print medium S to the first transport path H1 (S164).

[0265] Next, the control unit C determines whether the print medium S has passed the paper discharge sensor K4 (S165). If the print medium S has not passed the paper discharge sensor K4 (S165: No), the control unit C executes step S164. If the print medium S has passed the paper discharge sensor K4 (S165: Yes), the control unit C controls the main motor M0 to switch back the print medium S and transport it to the second transport path H2 (S166).

[0266] Next, the control unit C controls the main motor M0 to convey the printing medium S to the first conveying path H1 (S167). Next, the control unit C controls the image forming unit 4 to form an image on the back side of the printing medium S (S168). Step S168 is equivalent to the second image forming process. After step S168, the control unit C ends the image forming process (S119).

[0267] return Fig.10 After step S119, the control unit C determines whether there is a cutting instruction for the print job (S120). If there is no cutting instruction (S120: No), the control unit C discharges the print medium S to the discharge tray TR (S122) and ends the processing when receiving the print job. If there is a cutting instruction (S120: Yes), the control unit C controls the cutting mechanism 100 to perform a cutting process of cutting the print medium S into a first print medium and a second print medium (S121).

[0268] like Fig.11 As shown, after step S121, the control unit C discharges the second printing medium to the discharge tray TR (S123). Step S123 is equivalent to the first discharge process. Next, the control unit C determines whether an image is formed on the first printing medium (S124). In the case where an image is formed on the first printing medium (S124: Yes), the control unit C discharges the first printing medium to the discharge tray TR (S126). When the control unit C discharges the first printing medium, it ends the processing when receiving the printing job. In the case where no image is formed on the first printing medium (S124: No), the control unit C determines whether the size of the first printing medium can be maintained by the second conveying path H2 (S125).

[0269] When the size of the first print medium cannot be held by the second conveying path H2 (S125: No), the control unit C discharges the first print medium to the discharge tray TR (S126). When the first print medium is discharged, the control unit C ends the processing when receiving the print job. When the size of the first print medium can be held by the second conveying path H2 (S125: Yes), the control unit C determines whether the first print medium is set to be held by the print job (S127). When the first print medium is not set to be held (S127: No), the control unit C discharges the first print medium to the discharge tray TR (S126). When the first print medium is discharged, the control unit C ends the processing when receiving the print job.

[0270] When the first printing medium is set to be retained (S127: Yes), the control unit C controls the main motor M0 to convey the first printing medium to the second conveying path H2 (S128). Next, the control unit C retains the first printing medium in the second conveying path H2 (S129). Steps S124 to S129 correspond to the retaining process. In addition, steps S124 and S125 may be omitted from the retaining process.

[0271] Next, the control unit C determines whether an image is formed on both sides of the second print medium (S130). If no image is formed on both sides of the second print medium (S130: No), the control unit C adds 1 to the number of times N that the first print medium has passed through the fixing unit 45 (S131). If an image is formed on both sides of the second print medium (S130: Yes), the control unit C adds 2 to the number of times N that the first print medium has passed through the fixing unit 45 (S132). The number of times N in step S131 and step S132 is the number of times the portion of the print medium S corresponding to the first print medium before cutting actually passed through the fixing unit 45. After step S131 and step S132, the control unit C ends the processing when receiving the print job.

[0272] [Effects of the Third Embodiment]

[0273] According to the image forming apparatus 121 of the third embodiment as described above, the control unit C performs the re-inversion process after performing the holding process. According to the above configuration, the first printing medium held by the second conveying path H2 is once conveyed to the first conveying path H1, and then conveyed to the first conveying path H1 again via the second conveying path H2. The first printing medium can be conveyed in such a manner that the front side of the first printing medium conveyed to the first conveying path H1 again faces the transfer unit 42 of the image forming unit 4. Thus, an image forming apparatus with improved convenience compared to conventional image forming apparatuses can be provided.

[0274] In addition, the control unit C causes the first printing medium that has not been imaged by the first image forming process to be held by the second conveying path H2 through the holding process. According to the above configuration, no image is formed on the first printing medium held by the holding process. Therefore, even if the first image forming process is performed after the re-inversion process, a double image is not formed on the front side of the first printing medium. Thus, concerns about the quality of the image formed on the front side of the first printing medium being reduced can be reduced.

[0275] According to the above configuration, the second print medium is discharged to the discharge tray TR before the holding process is performed. Therefore, only the first print medium can be held in the second conveying path H2. That is, the concern that the first print medium and the second print medium collide in the second conveying path H2 can be reduced. Thus, the possibility of clogging in the second conveying path H2 can be reduced.

[0276] In addition, the control unit C performs the second discharge process after the holding process and before the second image forming process. According to the above configuration, when an image is formed on the front and back sides of the print medium S taken out from the feed tray 31, the first print medium held by the second conveying path H2 is first discharged to the discharge tray TR. Therefore, even if the print medium S taken out from the feed tray 31 is conveyed to the second conveying path H2, the print medium S will not collide with the first print medium. Thus, the possibility of clogging in the second conveying path H2 can be reduced. In addition, the image that should be formed on the back side of the print medium S taken out from the feed tray 31 will not be formed on the first print medium. Thus, the quality reduction of the image formed on the print medium S can be reduced.

[0277] In addition, the control unit C performs a determination process. According to the above configuration, whether to perform the re-reversal process on the first printing medium is determined based on the number of times the first printing medium passes through the fixing unit 45. Therefore, the first image forming process can be performed in consideration of the influence of the heat of the fixing unit 45 on the first printing medium. Thus, the quality degradation of the image formed on the first printing medium can be reduced.

[0278] In addition, when the control unit C determines that the number of times N is less than the threshold value γ in the determination process, the re-inversion process is executed. According to the above configuration, the re-inversion process can be executed only for the first printing medium determined to be less affected by the heat of the fixing unit 45. That is, the first image forming process is executed for the first printing medium that is less affected by the heat of the fixing unit 45. Thus, the quality degradation of the image formed on the first printing medium can be reduced.

[0279] In addition, when it is determined in the determination process that the number of times N exceeds the threshold value γ, the control unit C does not perform the re-reversal process. According to the above configuration, the re-reversal process is not performed on the first printing medium determined to be greatly affected by the heat of the fixing unit 45. That is, the first image forming process is not performed on the first printing medium that is greatly affected by the heat of the fixing unit 45. As a result, it is possible to reduce the degradation of the quality of the image formed on the first printing medium.

[0280] In addition, when it is determined in the determination process that the number of times N exceeds the threshold value γ, the control unit C executes the second discharge process. According to the above configuration, the second discharge process is executed for the first print medium determined to be greatly affected by the heat of the fixing unit 45. Therefore, the first print medium can be discharged to the discharge tray TR without executing the image forming process for the first print medium that is greatly affected by the heat.

[0281] In addition, the control unit C can set the temperature of the heating roller 45HR of the fixing unit 45 during the re-reversal process to the temperature α. According to the above configuration, during the re-reversal process, the thermal influence on the first printing medium caused by the first printing medium passing through the fixing unit 45 can be reduced. Thus, the quality degradation of the image formed on the first printing medium can be reduced.

[0282] In addition, the control unit C sets the temperature of the heating roller 45HR of the fixing unit 45 in the second discharge process to the temperature α. According to the above configuration, in the second discharge process, when the first print medium without an image formed thereon passes through the fixing unit 45, heat is not applied to the heating roller 45HR. Thus, the power consumption of the fixing unit 45 can be reduced.

[0283] [Fourth embodiment]

[0284] Next, based on Figures 14 to 18 Next, an image forming apparatus 131 according to a fourth embodiment will be described. In addition, for the sake of convenience of description, components having the same functions as those described in the first embodiment are denoted by the same reference numerals, and their description will not be repeated. Fig.14 This is a diagram for explaining a schematic configuration of an image forming apparatus 131 according to a fourth embodiment of the present invention.

[0285] [Configuration of Image Forming Device 131]

[0286] like Fig.14 As shown, as conveying rollers for discharging the first print medium and the second print medium subjected to the cutting process to the discharge tray TR described later, an upstream conveying roller 40A and a downstream conveying roller 40B are sequentially provided in the third conveying path H3. The upstream conveying roller 40A and the downstream conveying roller 40B are examples of discharge rollers involved in the fourth embodiment. In the third conveying path H3, the upstream conveying roller 40A and the downstream conveying roller 40B are provided along the conveying direction in a manner of sandwiching the cutting mechanism 100.

[0287] In addition, each roller including the pickup roller 32, separation roller 34, feed roller 35, positioning roller 36, transfer roller of the transfer section 42, intermediate discharge roller 37, and discharge roller 38, which are an example of a plurality of conveying sections, is configured so that the conveying speed of the print medium S becomes faster as the configuration position in the image forming device 131 is more toward the downstream side than the roller configured on the upstream side on the conveying path.

[0288] In addition, the conveying speed of the upstream conveying roller 40A and the downstream conveying roller 40B for the printing medium S is configured to be faster than the conveying speed of the pickup roller 32 for the printing medium S. Each roller changes the conveying speed by adjusting, for example, the roller diameter, the rotation speed of the motor, which is a driving source for driving the roller to rotate, or the gear ratio of the gear, which is a transmission mechanism for transmitting the driving force of the motor. Here, the main motor M0 is an example of the first motor, such as a brushless DC motor. In addition, the drive motor M2 is an example of the second motor, such as a stepping motor M2.

[0289] In addition, the main motor M0 is connected to the pickup roller 32 via a transmission mechanism. The transmission mechanism connected to the pickup roller 32 has a clutch 32A. The clutch 32A is configured to be switchable between a transmission state in which the driving force of the main motor M0 is transmitted to the pickup roller 32 and a release state in which the driving force of the main motor M0 is not transmitted to the pickup roller 32. That is, the driving force of the main motor M0 is transmitted to the pickup roller 32 via the clutch 32A.

[0290] Here, use Fig.15 The details of the cutting mechanism 100 will be described in detail. Fig.15 1 is a perspective view illustrating the cutting mechanism 100. Fig.15 As shown, the cutting mechanism 100 includes a frame 71, a slide rail 72, a blade 100A as an example of a cutting blade, a print medium passage portion 74, a blade 100B as an example of a cutting blade, a slide 76, a slide motor M1, a driving pulley 77, a driven pulley 78 and a pulley belt 79.

[0291] The frame 71 extends in a scanning direction which is the same direction as the axial direction of the photosensitive drum 46. The slide rail 72 is a rail formed on the frame 71 and extending in the scanning direction. The blade 100A is a fixed blade. The blade 100A is a flat blade fixed to the frame 71 and extending in the scanning direction. The print medium passage portion 74 is a space formed in the frame 71 for the print medium S to pass through. The print medium passage portion 74 is formed between the slide rail 72 and the blade 100A. The blade 100B is a disk-shaped blade and is rotatably fixed to the carriage 76.

[0292] The slide 76 is engaged with the slide rail 72 and is mounted on the frame 71 so as to be slidable along the slide rail 72. Fig.15 The carriage 76 moves from the initial position indicated by the solid line to the cutting completion position indicated by the dotted line. Fig.15 The initial position is indicated by the solid line. When the carriage 76 moves along the slide rail 72 to the cutting completion position, a sheet of printing medium S is sandwiched between the blade 100A and the blade 100B and cut into a first printing medium and a second printing medium.

[0293] The carriage motor M1 drives the carriage 76 independently of the main motor M0 based on an operation instruction from the control unit C. Specifically, the cutting mechanism 100 uses the rotational force of the carriage motor M1 to move the carriage 76 in the scanning direction, thereby cutting the print medium S. Thus, the cutting process of the blade 100A and the blade 100B is performed on the print medium S, and the print medium S is completely divided into the first print medium and the second print medium in the front and rear in the conveying direction. The cutting process is an example of a processing process.

[0294] In addition, the cutting mechanism 100 is described to be composed of a blade 100A and a blade 100B, but is not limited thereto. For example, the blade 100A may be a movable blade in the shape of a disk similar to the blade 100B rather than a fixed blade. In this case, the blade 100A and the blade 100B are both fixed to the carriage 76 in a rotatable manner.

[0295] In addition, if Fig.15 As shown in the figure, the blade 100A as a fixed blade is arranged on the upper side, and the blade 100B as a movable blade is arranged on the lower side than the blade 100A, but it is not limited to this structure. For example, the blade 100B as a movable blade may be arranged on the upper side, and the blade 100A as a fixed blade may be arranged on the lower side. In addition, the cutting mechanism 100 may also be a structure having only one of the blade 100A and the blade 100B.

[0296] The driving pulley 77 is provided on the other side of the scanning direction of the frame 71. The driving pulley 77 receives the driving force of the carriage motor M1 and can rotate forward and reverse. The driven pulley 78 is provided on one side of the scanning direction of the frame 71. The pulley belt 79 is wound around the driving pulley 77 and the driven pulley 78. In addition, the carriage 76 is fixed to the pulley belt 79.

[0297] Thus, the carriage 76 slides in the scanning direction according to the rotation of the pulley belt 79. Specifically, when the carriage motor M1 rotates forward, the carriage 76 slides from one side to the other side in the scanning direction, and when the carriage motor M1 rotates reversely, the carriage 76 slides from the other side to one side in the scanning direction.

[0298] [Operation Example of Image Forming Device 131]

[0299] See also below Fig.16, Fig.17 and Fig.18 , an operation example of the image forming apparatus 131 according to the fourth embodiment will be described in detail. Fig.16 This is a flowchart showing an example of the operation of the image forming apparatus 131 . Fig.17 It is a schematic diagram showing the initial position and the cutting completion position of the cutting operation of the cutting mechanism 100. Fig.18 This is a timing chart for explaining the supply of the printing medium S, the motor driving, and the cutting timing of the printing medium S controlled by the control unit C. In addition, in the following description, a case where an image forming process is performed on an A4-sized printing medium S is exemplified. Furthermore, in the following description, a case where the printing medium S is cut and divided into two A5-sized printing media, namely, a first printing medium and a second printing medium is exemplified.

[0300] The control unit C determines in S200 whether a print job has been received for the image forming apparatus 131. When the control unit C determines that a print job has not been received (S200: No), the control unit C sets the image forming apparatus 131 to a standby state.

[0301] On the other hand, when the control unit C determines that a print job has been received (S200: Yes), in S201, the first print medium S is supplied. Specifically, the control unit C drives the pickup roller 32 to rotate and feeds the print medium S stored in the feed tray 31 to the separation roller 34. The separation roller 34 separates the print medium S picked up by the pickup roller 32 one by one. The feed roller 35 conveys the print medium S toward the registration roller 36. The registration roller 36 aligns the position of the top end of the print medium S and then conveys the print medium S toward the image forming unit 4.

[0302] In addition, the control unit C may determine whether the front cover FC and the rear cover RC are in the closed state between S200 and S201. Specifically, the control unit C determines whether the front cover FC closes the opening 10B based on the detection result of the sensor K5.

[0303] Alternatively, the control unit C may determine whether the rear cover RC closes the rear opening 10C and the second discharge tray based on the detection result of the sensor K6. Alternatively, the control unit C may determine whether the storage cover 10A is closed relative to the main body housing 10 based on the detection result of the sensor K7.

[0304] Then, when the control unit C determines that the front cover FC, the rear cover RC, and the storage cover 10A are not all in the closed state, the control unit C may determine that the image forming device 131 is not in an operable state. In this case, the control unit C may set the image forming device 131 to a standby state. Thus, the image forming process for the print medium S and the processing for cutting the print medium S can be safely performed.

[0305] Next, in S202, the control unit C executes an image forming process (S202) for forming an image on the printing medium S through the image forming unit 4. Specifically, the printing medium S is passed through the drum nip formed between the photosensitive drum 46 and the transfer roller, thereby transferring the toner image on the surface of the photosensitive drum 46 to the printing medium S. Then, the control unit C drives the fixing unit 45 to heat and convey the printing medium S with the toner image formed thereon through the fixing nip, thereby fixing the toner image formed on the printing medium S to the printing medium S.

[0306] Next, in S203, the control unit C determines whether there is a cutting instruction from the cutting mechanism 100. When the control unit C determines that there is no cutting instruction from the cutting mechanism 100 (S203: No), the discharge process (S204) of discharging the first print medium S to the outside of the image forming apparatus 1 is executed. Specifically, the control unit C drives the drive motor M2 to operate the flap FP located near the confluence portion G2, thereby closing the conveying path to the third conveying path H3. As a result, the print medium S is guided by the flap FP and conveyed to the first conveying path H1. Then, the print medium S is discharged by the discharge roller 38 onto the discharge tray TR. When the discharge process is executed in S204, the control unit C completes the operation of the image forming apparatus 1.

[0307] On the other hand, in S203, when it is determined that there is a cutting instruction from the cutting mechanism 100 (S203: Yes), the control unit C drives the cutting mechanism 100 to perform the cutting process (S205). Fig.17 As shown, the control unit C moves the carriage 76 from the initial position toward the cutting completion position along the scanning direction intersecting the conveying direction.

[0308] In detail, Fig.18 As shown, the control unit C moves the carriage 76 by rotating the carriage motor M1 forward (time t1). Then, when the cutting of the print medium S is completed, the control unit C stops the carriage motor M1 (time t2). Thus, the print medium S is divided into the first print medium and the second print medium.

[0309] When the cutting process is completed, the control unit synchronously starts the supply of the next printing medium S and the discharge of the first printing medium and the second printing medium before the carriage 76 returns to the initial position. Specifically, when the cutting process is completed, the control unit C starts the forward rotation of the main motor M0 in S206 (time t3). At this time point, the clutch 32A connected to the main motor M0 is in a clutch-disconnected state.

[0310] When the main motor M0 is rotated forward, the control unit C determines in S207 whether the main motor M0 reaches a predetermined rotation speed. If it is determined that the rotation speed of the main motor M0 has not reached the predetermined rotation speed (S207: No), the control unit C waits until the rotation speed of the main motor M0 reaches the predetermined rotation speed.

[0311] This standby time is equivalent to Fig.18 The time tw between time t3 and time t4 is shown. The timing of the end of time tw, that is, the timing of time t4, is determined by whether the control unit C receives a main motor lock signal from a drive circuit (not shown) of the main motor M0.

[0312] In more detail, the control unit C determines whether the main motor lock signal is on or off based on whether the main motor lock signal is received. When it is determined that the main motor lock signal is on, the control unit C determines that the rotation speed of the main motor M0 becomes a prescribed rotation speed. The prescribed rotation speed is a rotation speed at which the pickup roller 32 can properly pick up the print medium S. The prescribed rotation speed has a range. In addition, as the conveying speed of the print medium S, in the case of a configuration in which a conveying speed suitable for printing quality is required, the rotation speed suitable for printing quality can be used as the prescribed rotation speed.

[0313] On the other hand, when it is determined that the rotation speed of the main motor M0 has reached the predetermined rotation speed (S207: Yes), the control unit C switches the clutch 32A to ON at S208 (time t4). When the clutch 32A is switched ON, the control unit C transmits the driving force of the main motor M0 to the pickup roller 32. Then, when the pickup roller 32 rotates forward, the control unit C starts supplying the second print medium S at S209 (time t4). The second print medium S is supplied from the time when the clutch 32A is switched ON at time t4 to the time when the clutch 32A is switched OFF at time t5.

[0314] The supply of the second print medium S is performed by clamping the pickup roller 32. In addition, the second print medium S is a print medium S different from the first print medium S (the first print medium and the second print medium) that has been cut at the time point t4. In addition, for convenience, the first print medium S and the second print medium S are described, but it can also be the third print medium S and the fourth print medium S. In other words, as long as it is a configuration of the subsequent print medium S of the print medium S that has been cut, such as the Nth (N is an integer greater than 1) print medium S and the N+1th print medium S that are supplied from the feed tray 31.

[0315] In addition, the control unit C starts the forward rotation of the stepper motor M2 at S210 (time t4). When the control unit C starts the forward rotation of the stepper motor M2, the driving force is transmitted to the upstream conveying roller 40A and the downstream conveying roller 40B, and at S211, the discharge process of the first print medium and the second print medium is performed. That is, at the timing of the completion of the cutting process, the control unit C starts the main motor M0 to rotate, and synchronously with the rotation speed of the main motor M0 becoming a rotation speed suitable for driving the pickup roller 32, the stepper motor M2 starts to rotate. As a result, the control unit C synchronously executes the start of the supply of the second print medium S, the discharge of the first print medium after the cutting process, and the discharge of the second print medium at the timing of time t4.

[0316] Next, when the control unit C executes the discharge processing of the first printing medium and the second printing medium in S211, it determines in S212 Fig.17 The rear end PE of the second printing medium shown here exceeds the scanning track PA of the blade 100B.

[0317] Whether the rear end PE of the second printing medium has passed the scanning track PA of the blade 100B is determined, for example, by a detection unit capable of detecting the length of the printing medium S. Specifically, the control unit C obtains the detection results of the length of the printing medium by the front positioning sensor K2 and the rear positioning sensor K3. Then, the control unit C obtains an output signal from an encoder (not shown) used to estimate the conveyance amount of the printing medium S whose length is detected. The control unit C determines whether the rear end PE of the second printing medium has passed the scanning track PA of the blade 100B by estimating the conveyance amount of the printing medium S based on the output signal from the encoder.

[0318] Then, when it is determined that the rear end PE of the second printing medium has not passed over the scanning track PA of the blade 100B (S212: No), the control unit C continues the discharge process of the first printing medium and the second printing medium in S211. On the other hand, when it is determined that the rear end PE of the second printing medium has passed over the scanning track PA of the blade 100B (S212: Yes), the control unit C returns the carriage 76 to the initial position in S213.

[0319] Specifically, if Fig.18 As shown in FIG. 1 , when it is determined that the rear end PE of the second printing medium has passed the scanning track PA of the blade 100B, the control unit C stops the rotation of the stepping motor M2 at the timing of the discharge completion of the second printing medium (time t6). Then, the control unit C starts the reverse rotation of the carriage motor M1 at time t7, and moves the carriage 76 from the cutting completion position to the initial position. When the carriage 76 returns to the initial position from the cutting completion position, the control unit C stops the carriage motor M1 (time t8).

[0320] [Effects of the Fourth Embodiment]

[0321] As described above, according to the image forming apparatus 131 of the fourth embodiment, at the timing when the cutting process, which is an example of the processing process, is completed, the control unit C synchronously executes the start of supplying the second print medium S and the start of discharging the print medium S cut by the cutting process. As a result, the timing of discharging the cut first print medium and the second print medium and the timing of supplying the second print medium S can be improved compared with the related art.

[0322] In addition, at the timing when the cutting process is completed, the control unit C can synchronously start the supply of the second print medium S and the discharge of the print medium cut by the cutting process before the carriage 76 returns to the initial position. As a result, the timing of discharging the divided first print medium and the second print medium and the timing of supplying the second print medium S can be improved compared to the past. In addition, the timing of supplying the second print medium S and discharging the cut print medium S can be advanced by the time it takes for the carriage 76 to return to the initial position compared to the past.

[0323] In addition, the control unit C returns the carriage 76 from the cutting completion position to the initial position at the timing when the rear end PE of the second printing medium cut by the cutting process passes over the scanning track PA of the blade 100B. Thus, the carriage 76 can be returned to the initial position at the most appropriate timing, and the timing of discharging the cut first printing medium and the second printing medium and the timing of supplying the second printing medium S can be improved compared with the conventional method.

[0324] In addition, the control unit C starts feeding the print medium S by driving the pickup roller 32. Thus, the print medium S placed on the feed tray 31 can be smoothly picked up. Thus, the timing of discharging the cut first print medium and the second print medium and the timing of feeding the second print medium S can be easily improved compared with the past.

[0325] In addition, at the timing when the cutting process is completed, the control unit C starts the rotation of the stepping motor M2 to drive the upstream conveying roller 40A and the downstream conveying roller 40B in synchronization with the rotation speed becoming suitable for driving the pickup roller 32. As a result, the upstream conveying roller 40A and the downstream conveying roller 40B can be driven while ensuring the rotation speed of the pickup roller 32. Therefore, the timing of discharging the first print medium and the second print medium after the cutting and the timing of supplying the second print medium S can be improved compared with the past.

[0326] Furthermore, the control unit C makes the rotation speed of the main motor M0 at the time when the pickup roller 32 clamps the second print medium S a rotation speed suitable for driving the pickup roller 32 , thereby enabling the second print medium S to be fed satisfactorily.

[0327] Furthermore, since the clutch 32A that connects the main motor M0 and the pickup roller 32 is provided, the control unit C can wait until the rotation speed of the main motor M0 reaches a rotation speed suitable for driving the pickup roller 32 .

[0328] In addition, the control unit C can increase the conveying speed of the conveying unit provided on the downstream side of the conveying path among the plurality of conveying units (the pickup roller 32, the separation roller 34, the feed roller 35, the registration roller 36, the transfer roller of the transfer unit 42, the intermediate discharge roller 37, and the discharge roller 38). Thus, the print medium S can be conveyed in such a manner that the print medium S supplied by the pickup roller 32 does not catch up with another print medium conveyed on the upstream side.

[0329] That is, it is possible to appropriately ensure the interval between the printing media S for conveying the printing media S. In addition, by increasing the conveying speed of the conveying unit on the downstream side, the conveyed printing media S can be stretched from the downstream side. Thus, the deflection of the printing media S during conveyance can be suppressed, and the clogging of the printing media S can be reduced.

[0330] In addition, the upstream conveying roller 40A and the downstream conveying roller 40B convey the print medium S faster than the pickup roller 32. As a result, the print medium S supplied by the pickup roller 32 can be prevented from catching up with the print medium S conveyed by the upstream conveying roller 40A and the downstream conveying roller 40B. In other words, the interval between the print media S for conveying the print media S can be appropriately ensured.

[0331] [Fifth embodiment]

[0332] Next, based on Figure 19 to Figure 21 Next, an image forming apparatus 141 according to a fifth embodiment will be described. For convenience of description, components having the same functions as those described in the first and fourth embodiments are denoted by the same reference numerals, and description thereof will not be repeated. Fig.19 It is a diagram for explaining a schematic configuration of an image forming apparatus 141 according to a fifth embodiment of the present invention.

[0333] [Configuration of Image Forming Device 141]

[0334] like Fig.19 As shown in FIG. 1 , the image forming apparatus 141 according to the fifth embodiment has a configuration basically the same as that of the image forming apparatus 131 according to the fourth embodiment. Fig.19 As shown, the image forming apparatus 141 according to the fifth embodiment is different in that it does not include a stepping motor M2 which is a driving motor M2.

[0335] Since the image forming device 141 does not include the stepping motor M2, the main motor M0 is used to execute the driving control of the upstream conveying roller 40A and the downstream conveying roller 40B by the control unit C. That is, the upstream conveying roller 40A and the downstream conveying roller 40B are connected to the main motor M0 and the driving force of the main motor M0 is transmitted to them. The main motor M0 is an example of a third motor, such as a brushless DC motor.

[0336] [Operation Example of Image Forming Device 141]

[0337] Below, use Fig. 20 and Fig.21 , an operation example of the image forming device 141 is described in detail. Fig. 20 This is a flowchart showing an example of the operation of the image forming apparatus 141 . Fig.21 1 is a timing chart for explaining the supply of the printing medium S, the motor driving, and the cutting timing of the printing medium S controlled by the control unit C. Fig. 20 S200~S205 shown in FIG. Fig.16 S200 to S205 shown are the same, so the description is omitted.

[0338] When the cut-off process of S205 is completed, the control unit C starts the forward rotation of the main motor M0 in S306. Fig.21 As shown, at time t10, the control unit C moves the carriage 76 by rotating the carriage motor M1 forward.

[0339] Then, at time t11, the control unit C stops the carriage motor M1 when the cutting of the print medium S is completed. Thus, the print medium S is divided into the first print medium and the second print medium. Then, the control unit C starts driving the pickup roller 32 and the upstream conveying roller 40A and the downstream conveying roller 40B by the main motor M0 at the timing when the cutting process is completed. As a result, the control unit C executes the discharge process of the first print medium and the second print medium and starts the supply of the second print medium S.

[0340] Specifically, at time t12, when the main motor M0 starts to rotate forward (S306), the control unit C drives the upstream conveying roller 40A and the downstream conveying roller 40B connected to the main motor M0 to rotate. When the upstream conveying roller 40A and the downstream conveying roller 40B are driven to rotate, the discharge process of the first printing medium and the second printing medium is performed (S307). The discharge process starts at time t12 and is completed at time t15. At this time point, the clutch 32A connected to the main motor M0 is in a clutch-disconnected state.

[0341] Furthermore, at time t12, when the main motor M0 is rotated forward, the control unit C determines in S308 whether the main motor M0 has reached the specified rotation speed. If it is determined that the rotation speed of the main motor M0 has not reached the specified rotation speed (S308: No), the control unit C waits until the rotation speed of the main motor M0 reaches the specified rotation speed. This waiting time is equivalent to the time from Fig. 20 The time tw between time t12 and time t13 is shown.

[0342] On the other hand, when it is determined that the rotation speed of the main motor M0 has reached the predetermined rotation speed (S308: Yes), the control unit C switches the clutch 32A to ON at S309 (time t13). When the control unit C switches the clutch 32A to ON, the driving force of the main motor M0 is transmitted to the pickup roller 32. Then, when the pickup roller 32 rotates forward, the control unit C starts supplying the second print medium S at S310 (time t13) (CL9). The second print medium S is supplied from the time when the clutch 32A is switched ON at time t13 to the time when the clutch 32A is switched OFF at time t14.

[0343] Next, for the second print medium that has been discharged in S307, the control unit C determines in S311 that Fig.17 The rear end PE of the second printing medium shown here exceeds the scanning track PA of the blade 100B.

[0344] Then, when it is determined that the rear end PE of the second printing medium has not passed over the scanning track PA of the blade 100B (S311: No), the control unit C continues the discharge process of the first printing medium and the second printing medium in S307. On the other hand, when it is determined that the rear end PE of the second printing medium has passed over the scanning track PA of the blade 100B (S311: Yes), the control unit C returns the carriage 76 to the initial position in S312.

[0345] Specifically, when it is determined that the rear end PE of the second printing medium has passed the scanning track PA of the blade 100B, the control unit C reverses the carriage motor M1 at the timing of the completion of the discharge of the second printing medium (time t16). When the carriage motor M1 is reversed, the control unit C moves the carriage 76 from the cutting completion position to the initial position. When the carriage 76 returns to the initial position from the cutting completion position, the control unit C stops the carriage motor M1 (time t17).

[0346] [Effects of the Fifth Embodiment]

[0347] As described above, according to the image forming apparatus 141 of the fifth embodiment, the control section C starts driving the pickup roller 32 and the upstream conveying roller 40A and the downstream conveying roller 40B by the main motor M0 at the timing when the cutting process is completed. Thus, compared with the case where the motors connected to the pickup roller 32 and the upstream conveying roller 40A and the downstream conveying roller 40B are controlled separately, the pickup roller 32 and the upstream conveying roller 40A and the downstream conveying roller 40B can be easily driven at the same time.

[0348] In addition, a clutch 32A is provided to connect the main motor M0 and the pickup roller 32. As a result, in a configuration in which the pickup roller 32 and the upstream and downstream conveying rollers 40A and 40B are driven simultaneously, the control unit C can wait until the rotation speed of the main motor M0 reaches a rotation speed suitable for driving the pickup roller 32.

[0349] [Modification 1]

[0350] In the first to fifth embodiments described above, each image forming device 1, 111, 121, 131, 141 is a monochrome printer that performs image forming processing of monochrome images, but may be, for example, a color printer that performs image forming processing of full-color images. In addition, each image forming device 1, 111, 121, 131, 141 is not limited thereto, and may be an MFP (Multi-Function Peripheral) having multiple functions such as a printing function of an inkjet printer, a scanning function, a copying function, and a fax function.

[0351] [Additional Notes]

[0352] The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope indicated by the claims. Embodiments obtained by appropriately combining technical means disclosed in different embodiments are also included in the technical scope of the present invention.

[0353] Explanation of symbols

[0354] 1 image forming device, 4 image forming unit, 41 exposure unit, B light beam, 41R polygon mirror, 41M polygon mirror motor, 42 transfer unit, 44 toner cartridge, 44R developing roller, 45 fixing unit, 45H heater, 46 photosensitive drum, 47 drum cartridge, 10 main body casing, 38 discharge roller, 100 cutting mechanism (processing unit), 100A, 100B blades (cutting blades), M1 carriage motor, M0 main motor, K2 front registration sensor (detection unit), K3 rear registration sensor (detection unit), TR discharge tray (first discharge unit), FC front cover.

Claims

1. An image forming device, characterized in that: have: an image forming unit including a photosensitive drum, a developing roller, a transfer unit, and a fixing unit, wherein the developing roller supplies toner to the photosensitive drum, the transfer unit transfers the toner supplied to the photosensitive drum to a printing medium, and the fixing unit fixes the toner transferred to the printing medium on the printing medium; a processing section disposed downstream of the fixing section in a conveying direction of the printing medium and performing processing for cutting the printing medium; as well as a control unit that performs a double-sided printing process in which the image forming unit performs printing on both sides of the printing medium, The control unit executes a processing process for performing processing for cutting the print medium by the processing unit after executing the double-sided printing process.

2. The image forming apparatus according to claim 1, wherein: The double-sided printing process includes: a first image forming process of forming an image on one side of the printing medium by the image forming unit; and A second image forming process is performed after the first image forming process to form an image on the other surface of the printing medium by the image forming unit.

3. The image forming apparatus according to claim 1 or 2, characterized in that: The processing unit is configured to cut the printing medium. The processing is a processing in which the printing medium is cut into a first printing medium and a second printing medium in front and behind in the conveyance direction by the processing unit.

4. The image forming apparatus according to claim 2, wherein: Also available: a main body housing having a first discharge portion for discharging the printing medium that has passed through the fixing portion; a first conveying path for conveying the printing medium that has passed through the fixing unit toward the first discharge unit; as well as A second conveyance path different from the first conveyance path is used to convey the printing medium that has passed through the fixing unit toward the photosensitive drum again after the first image forming process.

5. The image forming apparatus according to claim 4, wherein: further comprising a discharge roller configured to transport the print medium having passed through the fixing unit toward the first discharge unit, After the first image forming process and before the second image forming process, the control unit executes a reverse conveyance process in which the print medium is switched back from the first conveyance path by the discharge roller and conveyed to the second conveyance path.

6. The image forming apparatus according to claim 4, wherein: further comprising a third conveying path different from the first conveying path, the third conveying path being used to convey the printing medium having passed through the fixing section toward the processing section, The processing unit is provided on the third conveying path.

7. The image forming apparatus according to claim 4, wherein: The processing unit is provided on the first conveying path.

8. The image forming apparatus according to any one of claims 4 to 7, characterized in that: The image forming unit includes a drum cartridge or a toner cartridge, the drum cartridge includes the photosensitive drum, and the toner cartridge includes the developing roller. The main body housing further comprises a front cover and a rear cover, wherein the front cover can open and close an opening for loading and unloading the drum cartridge or the toner cartridge, and the rear cover can close a second discharge portion different from the first discharge portion, the second discharge portion being used to discharge the printing medium that has passed through the fixing portion. The control section executes the first image forming process, the second image forming process, and the processing process when the front cover closes the opening and the rear cover closes the second discharge section.

9. The image forming apparatus according to claim 2, wherein: The apparatus further comprises a detection unit which is disposed upstream of the image forming unit in the conveying direction and is capable of detecting the length of the printing medium in the conveying direction. The control unit executes a detection process in which the detection unit detects the length of the printing medium in the conveying direction. When the length of the print medium detected by the detection process is longer than a predetermined length, the control unit executes the first image forming process, the second image forming process, and the processing process.

10. The image forming apparatus according to claim 2, wherein: A main motor is further provided, and the main motor drives the photosensitive drum, the developing roller, the transfer unit or the fixing unit.

11. The image forming apparatus according to claim 10, wherein: The processing unit has: Cutting blades; a carriage that holds the cutting blade and is movable in a prescribed direction; and A carriage motor, distinct from the main motor, drives the carriage.

12. The image forming apparatus according to claim 11, wherein: When executing the processing, the control unit drives the carriage motor after stopping the main motor.

13. The image forming apparatus according to any one of claims 10 to 12, characterized in that: The image forming unit further includes an exposure unit that exposes the photosensitive drum to light. The exposure unit comprises: a polygonal mirror for irradiating a prescribed light beam to the photosensitive drum; and A polygonal mirror motor different from the main motor drives the polygonal mirror to rotate.

14. The image forming apparatus according to claim 13, wherein: When a print job for a plurality of print media is received, The control unit drives the polygonal mirror motor when the image forming unit executes the first image forming process on the second print medium while executing the processing on the first print medium.

15. The image forming apparatus according to claim 13, wherein: When a print job for a plurality of print media is received, The control unit stops the polygonal mirror motor if the image forming unit does not execute the first image forming process on the second printing medium while executing the processing on the first printing medium.

16. The image forming apparatus according to claim 1 or 2, characterized in that: The fixing unit includes a heater for heating the printing medium. The control unit stops the heater when executing the processing.

17. The image forming apparatus according to claim 5, wherein: When receiving a print job for the print medium, When the print job includes print data of 4N+1 pages, where N is an integer greater than or equal to 0, the control unit, when determining that the print data for the print medium on which the processing has not been performed is print data for the final page, performs processing including the following processing: a third image forming process of forming the image of the final page on either side of the print medium by the image forming unit; and The printing medium after the third image forming process is subjected to the processing by the processing unit without performing the reverse conveying process.

Images