Image forming apparatus

Abstract

To provide an image forming apparatus that, even when a consumable item is replaced during printing, can resume the printing within a shorter time than before.SOLUTION: The present invention is an image forming apparatus that forms an image on a roll paper conveyed along a paper feed path, and has: an intermediate transfer body that carries developer images; image forming means that forms the developer images on the intermediate transfer body; transfer means that transfers the developer images on the intermediate transfer body to a roll paper; fixing means that fixes the transferred developer images; an image formation control unit that controls an initial operation of the image forming means; and a fixing control unit that calculates the predicted time of warm-up of the fixing means on the basis of information on the roll paper and the temperature of the fixing means, and starts the warm-up during the initial operation of the image forming means so that the warm-up is completed at the timing when the initial operation is completed. The initial operation of the image forming means and the warm-up are executed in a situation where the roll paper is fed to the paper feed path.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an image forming apparatus, and can be applied to, for example, an image forming apparatus that prints on a long medium such as continuous paper (roll paper). [Background technology]

[0002] Conventionally, when an image forming apparatus detects the end of the life of a consumable part during printing, the image forming apparatus stops paper transport and prompts the user to replace the consumable part. After the user replaces the consumable part, the image forming apparatus resumes printing.

[0003] Incidentally, when a consumable is replaced, the image forming apparatus must perform initialization processes such as aging processing, waiting for toner supply, and processing for correcting color registration and density, as well as warming up the fixing unit, before resuming printing.

[0004] For example, Patent Document 1 discloses an image forming apparatus that performs an initialization process when a toner cartridge is replaced, and Patent Document 2 discloses a technique related to a warm-up operation of a fixing unit of an image forming apparatus. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2010-266588 A [Patent Document 2] JP 2017-181937 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in a conventional image forming apparatus, when a consumable item is replaced, it takes time before printing can be resumed because the image forming apparatus must start a warm-up operation for the fixing unit after the above-mentioned initialization process is performed.

[0007] Therefore, there is a demand for an image forming apparatus that can resume printing in a shorter time than before even when a consumable is replaced during printing. [Means for solving the problem]

[0008] The present invention is an image forming device that forms an image on roll paper transported along a paper passage path, comprising: (1) an intermediate transfer body that carries a developer image; (2) an image forming means that forms the developer image on the intermediate transfer body based on image data; (3) a transfer means that transfers the developer image on the intermediate transfer body to the roll paper; (4) a fixing means that fixes the developer image transferred by the transfer means; (5) an image forming control unit that controls the initial operation of the image forming means; and (6) a fixing control unit that calculates an expected warm-up operation of the fixing means based on media information of the roll paper and the temperature of the fixing means, and starts the warm-up operation of the fixing means during the initial operation of the image forming means so that the warm-up operation of the fixing means is completed at the timing when the initial operation of the image forming means is completed; and (7) the initial operation of the image forming means and the warm-up operation of the fixing means are performed with the roll paper passed through the paper passage path. Effect of the Invention

[0009] According to the present invention, even if a consumable is replaced during printing, printing can be resumed in a shorter time than before. [Brief description of the drawings]

[0010] [Figure 1] FIG. 2 is a block diagram showing the configuration of a control system of the printer according to the embodiment. [Diagram 2] 1 is a diagram showing an outline of the overall configuration of a printer according to an embodiment; [Diagram 3] 4 is a flowchart showing a characteristic operation (initial processing) of the printer according to the embodiment. [Figure 4] 4 is a flowchart showing a characteristic operation (advance warm-up) of the printer according to the embodiment. [Diagram 5] FIG. 2 is an explanatory diagram showing an example of the contents of each initial process and a prediction of the time required for each process according to the embodiment. [Figure 6] FIG. 4 is an explanatory diagram showing an example of a temperature rise table according to the embodiment; [Figure 7] 5A and 5B are schematic diagrams illustrating a state in which a secondary transfer roller and a transfer belt are separated from each other according to the embodiment. [Figure 8] 6 is a flowchart showing operations of fixing warm-up and image initial during advance warm-up according to the embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] (A) Main embodiment An embodiment of an image forming apparatus according to the present disclosure will be described in detail below with reference to the drawings. In the following, an example in which the image forming apparatus according to the present disclosure is applied to a printer will be described.

[0012] (A-1) Configuration of the embodiment FIG. 2 is a diagram showing an outline of the overall configuration of the printer according to the embodiment.

[0013] In FIG. 2, the printer 1 is a printer that prints on paper P as a long medium, and has a main body section 20 that forms an image on the paper P, and a paper supply section 10 that supplies the paper P to the main body section 20.

[0014] The paper supply unit 10 is attached to the lower front surface of the main body 20, and includes a paper holder 11, a guide roller 12, a medium transport sensor S1, a cutter unit 14, and transport rollers 15.

[0015] The paper holder 11 is provided at the front end of the paper supply unit 10, and rotatably holds paper P as a medium wound in a roll. A transport path R1 that connects the paper holder 11 and the main body unit 20 is provided inside the paper supply unit 10.

[0016] Guide roller 12 is provided behind paper holder 11 and guides the paper fed out from paper holder 11 to transport path R1.

[0017] Along the transport path R1, a medium transport sensor S1 and a cutter unit 14 are provided in this order from the upstream side in the paper transport direction (i.e., the side closer to the paper holding unit 11). Furthermore, within the paper supply unit 10, a plurality of transport rollers 15 are provided along the transport path R1.

[0018] The transport rollers 15 transport the paper P fed out from the paper holder 11 to the main body 20 along the transport path R1.

[0019] The medium transport sensor S1 detects the presence or absence of paper P passing through the transport path R1, transport abnormalities, and the like.

[0020] The cutter unit 14 cuts the paper P in the width direction perpendicular to the conveying direction as required.

[0021] The main body 20 has medium transport sensors S2 and S3, a fixing unit 21, a transport roller 22, and an image forming unit 30. A transport path R2 is provided inside the main body 20, extending from the lower front surface to the lower rear surface. The front end of the transport path R2 is connected to the transport path R1 of the paper supply unit 10, and the rear end is connected to a paper discharge port 23 provided on the rear surface of the main body 20. In the main body 20, the medium transport sensor S2, the image forming unit 30, the fixing unit 21, and the medium transport sensor S3 are provided along the transport path R2 in this order from the upstream side in the paper transport direction. Furthermore, a plurality of transport rollers 22 are provided inside the main body 20 along the transport path R2.

[0022] The fixing unit 21 fixes the toner image transferred onto the paper P by the image forming unit 30 onto the paper P by applying heat and pressure.

[0023] The transport rollers 22 transport the paper P supplied from the paper supply unit 10 along the transport path R2 to the image forming unit 30 and the fixing unit 21, and then discharge the paper P from the paper discharge opening .

[0024] The medium transport sensors S2 and S3 detect the presence or absence of paper P passing through the transport path R2, transport abnormalities, etc. The number and locations of the medium transport sensors S disposed within the printer 1 are not particularly limited.

[0025] Image forming unit 30 includes toner cartridges 31 (31Y, 31M, 31C, 31K, 31W), photoconductor drums 32 (32Y, 32M, 32C, 32K, 32W) as image forming means, a transfer belt 33 as an intermediate transfer body, a secondary transfer roller 34, etc.

[0026] The image forming unit 30 transfers a developer image (hereinafter also referred to as a "toner image") developed with toner of each color onto the surface of the paper P transported along the transport path R2, thereby forming an image on the paper P. In this embodiment, the image forming unit 30 employs a secondary transfer method in which the toner images formed on the photoconductor drums 32 are primarily transferred onto the transfer belt 33, and then the toner images are secondarily transferred from the transfer belt 33 onto the paper P.

[0027] The toner cartridges 31 (31Y, 31M, 31C, 31K, 31W) contain toner of the corresponding color (yellow, magenta, cyan, black, white).

[0028] The photoconductor drums 32 (32Y, 32M, 32C, 32K, 32W) are cylindrical members that carry electrostatic latent images on their surfaces, and are constructed using photoconductors. The photoconductor drums 32 are supplied with toner so that an image corresponding to the electrostatic latent image is formed (developed).

[0029] The transfer belt 33 is rotatably stretched around a plurality of rollers such as belt rollers, and conveys the toner image formed by the photosensitive drum 32 to a secondary transfer roller .

[0030] The secondary transfer roller 34 transfers the toner image formed on the transfer belt 33 onto a continuous, long sheet of paper P.

[0031] Next, there will be described the configuration of the control system of the printer 1. Fig. 1 is a block diagram showing the configuration of the control system of the printer according to the embodiment.

[0032] 1, the printer 1 has an initial control unit 101 as an image formation control unit, a consumables management unit 103, and a print control unit 104. The initial control unit 101, the consumables management unit 103, and the print control unit 104 are configured to operate as functional units corresponding to various programs by reading out various programs stored in a storage unit (not shown) into a memory (not shown) and executing the programs.

[0033] The initial control unit 101 performs initialization (including correction, etc.) when the power is turned on, when an error is cleared, or when a consumable is replaced. The initial control unit 101 has an initial completion time prediction unit .

[0034] The initial completion time prediction unit 102 determines the contents to be performed in the initialization based on the information held by the consumables management unit 103, and predicts the completion time of the initialization based on the contents.

[0035] The consumables management unit 103 detects the management of the usage amount and replacement of consumables implemented in the printer 1. In this embodiment, the printer 1 holds, as detachable consumables, toner cartridges 31 (31Y, 31M, 31C, 31K, 31W), photoconductor drums 32 (32Y, 32M, 32C, 32K, 32W), transfer belt 33, fixing unit 21, and cutter unit 14.

[0036] The print control unit 104 performs printing at a print speed and fixing temperature suitable for the paper P specified by the user. The print control unit 104 includes a print medium storage unit 105 and a fixing control unit .

[0037] The print medium storage unit 105 stores information about the last printed sheet P and the sheet P being printed.

[0038] The fixing control unit 106 controls the speed and temperature of the fixing unit 21 based on the information of the paper P stored in the print medium storage unit 105. The fixing control unit 106 holds a current temperature 107, a target temperature 108, and a temperature rise table 109, and controls a fixing temperature sensor 110 (not shown).

[0039] The fixing temperature sensor 110 measures the temperature of the fixing unit 21 .

[0040] A current temperature 107 is the current temperature of the fixing unit 21 measured by a fixing temperature sensor 110. A target temperature 108 is a fixing target temperature for each paper P that is specified.

[0041] The temperature rise table 109 is a table showing the temperature rise of the fixing unit 21 over time for each type of paper P.

[0042] Next, the initialization process (image initial process) when replacing consumables and the prediction of the time required for each process will be described. Fig. 5 shows an example of the contents of each initial process according to the embodiment and the prediction of the time required for each process. The initial completion time prediction unit 102 predicts the completion time of the initial according to each initial I1 to I4 shown in Fig. 5 below.

[0043] 5A is applied when the photoconductor drum 32 is replaced with a new one. In addition to checking each medium transport sensor S and checking the installation of consumables, initial I1 requires aging processing, density correction, and full-size color shift correction. Also, a check of the toner sensor (not shown) that detects the toner supplied to the photoconductor drum 32 is performed in parallel with the aging processing.

[0044] The initial I2 shown in Fig. 5B is applied when the photoconductor drum 32 is replaced with a used one. The initial I2 requires a check of each medium transport sensor S, a check of the installation of consumables, as well as density correction and full-size color shift correction. Also, the toner sensor check is performed in parallel with the aging process.

[0045] The initial I3 shown in Fig. 5(C) is applied when the toner cartridge 31 is replaced after detecting toner low / toner empty. In addition to checking each medium transport sensor S and checking the installation of the consumables (toner cartridge 31), the initial I3 requires waiting for the toner sensor to detect toner full, density correction, and color misregistration correction for fine adjustment only. Also, the toner sensor is checked in parallel with waiting for toner full detection.

[0046] 5D is applied when the toner cartridge 31 has been replaced without detecting toner low / empty (or when neither the toner cartridge 31 nor the photoconductor drum 32 has been replaced). In addition to checking each medium transport sensor S and the installation of consumables, initial I4 requires checking the toner sensor and performing color shift correction with only fine adjustment.

[0047] Next, the time required for warming up the fixing unit 21 (warming up process) will be described.

[0048] Fig. 6 is an explanatory diagram showing an example of a temperature rise table according to the embodiment. In Fig. 6, the temperature rise table 109 shows the correlation between the elapsed time and the fixing temperature when the heater (heating element such as a halogen lamp) inside the fixing unit 21 is turned on (heated) for each type of medium. In Fig. 6, the correlation for each of two types of medium (paper P), namely, label paper and plain paper light, is shown, but the medium type is not particularly limited. The fixing control unit 106 uses the correlation in the temperature rise table 109 to predict the time required to raise the fixing temperature from the current temperature 107 to the target temperature 108.

[0049] Next, supplementary details of the image initial processing executed in the image forming unit 30 and the warm-up processing of the fixing unit 21 will be described.

[0050] FIG. 7 is a schematic diagram showing the state of separation between the secondary transfer roller and the transfer belt according to the embodiment.

[0051] 7, during the initialization process, inside the printer 1, the secondary transfer roller 34 and the opposing transfer belt 33 are separated from each other so as not to interfere with each other. Therefore, it is not necessary to make the image initial speed (transport speed on the transfer belt 33) for aging, density, color shift correction, etc. of the photosensitive drum 32 equal to the warm-up speed (fixing warm-up speed) of the fixing unit 21 (transport speed on the transport paths R1 and R2).

[0052] Image initialization on the transfer belt 33 is most accurate when performed at the actual initialization speed (printing speed), and the faster the speed, the sooner it will be completed. On the other hand, fixing warm-up is performed at a slower speed, as less heat is absorbed by the paper P, and the temperature rises more quickly. Also, since the paper P is transported even during fixing warm-up, a slower speed reduces the distance the paper P is transported, resulting in less wasted paper.

[0053] After the secondary transfer roller 34 and the transfer belt 33 are separated, the image initial speed is fast and the fixing warm-up speed is slow, which can reduce paper waste and the fixing warm-up time (=reduction in power consumption).

[0054] (A-2) Operation of the embodiment Next, the operation of the printer 1 according to the embodiment having the above configuration will be described.

[0055] 3 is a flowchart showing a characteristic operation (initialization process) of the printer 1 according to the embodiment. When all covers (not shown) are closed, the printer 1 performs an initialization process (initialization process).

[0056] (A-2-1) Overall flow of initialization process <s101> First, the initial control unit 101 judges whether the only cover that has been opened or closed (not shown) on the printer 1 is the top cover. If a cover other than the top cover has been opened or closed (S101-NO), the initial control unit 101 proceeds to step S108 (normal initial processing) since there is a possibility that the state of the paper P has not been maintained. On the other hand, if only the top cover has been opened or closed (S101-YES), the initial control unit 101 proceeds to step S102.

[0057] <s102> Before the cover is opened, the initial control unit 101 checks whether the paper P continues to pass through and whether the toner cartridge 31 or the photosensitive drum 32 has reached the end of its life.

[0058] If paper was not passing before the cover was opened, or if the toner cartridge 31 or the photosensitive drum 32 is not in an end-of-life state (S102-No), the initial control unit 101 proceeds to step S108 (normal initial processing) because it is unclear whether printing will resume immediately after the initial processing.

[0059] On the other hand, if the paper was passing before the cover was opened and the toner cartridge 31 or the photosensitive drum 32 is in the end of life state (S102-Yes), the initial control unit 101 proceeds to step S103.

[0060] <s103> The initial control unit 101 checks each medium transport sensor S, and confirms that the state of each medium transport sensor S has not changed before and after the cover is opened and closed (that the paper passing state is maintained).

[0061] If the state of the medium transport sensor S has changed (S103-No), the initial control unit 101 proceeds to step S109. On the other hand, if the state of the medium transport sensor S has not changed (S103-Yes), the initial control unit 101 proceeds to step S104.

[0062] <s104> The consumables management unit 103 reads the information on the consumables, compares it with the consumables information before the cover was opened, and checks whether the consumables have been replaced.

[0063] <s105> The initial control unit 101 checks whether replacement of the transfer belt 33 or the fixing unit 21 has been detected by the consumables management unit 103. If the initial control unit 101 detects replacement of the transfer belt 33 or the fixing unit 21 (S105-Yes), the initial control unit 101 proceeds to step S108 (normal initial processing) since the state of the conveying paths R1 and R2 has changed and the paper passing state cannot be maintained. On the other hand, if the initial control unit 101 has not detected replacement of the transfer belt 33 or the fixing unit 21 (S105-No), the initial control unit 101 proceeds to step S106.

[0064] <s106> The initial control unit 101 checks whether replacement of the toner cartridge 31 or the photosensitive drum 32 has been detected by the consumables management unit 103. If the initial control unit 101 has not detected replacement of the toner cartridge 31 or the photosensitive drum 32 (S106-No), the lifespan state continues, so the process proceeds to step S108 (normal initial processing). On the other hand, if the initial control unit 101 detects replacement of the toner cartridge 31 or the photosensitive drum 32, the process proceeds to step S107 (advance warm-up).

[0065] <s107> When the initial control unit 101 detects the replacement of the toner cartridge 31 or the photosensitive drum 32 in the above-mentioned step S106 (S106-Yes), it performs a pre-warm-up (S107). The details of this pre-warm-up will be described later.

[0066] <s108> If it is determined in each of the above processes that it is not appropriate to perform the advance warm-up, the initial control unit 101 performs a normal initial process.

[0067] <s109> Furthermore, when it is determined in step S103 that the state of the medium transport sensor S has changed (S103-No), the initial control unit 101 determines whether all the medium transport sensors S are OFF.

[0068] If all the medium transport sensors S are OFF (S109-Yes), the initial control unit 101 determines that the paper P has been removed and printing will not continue, cancels the paper passing state, and proceeds to the above-mentioned step S108 (normal initial processing). On the other hand, if some of the medium transport sensors S are ON (S109-No), the initial control unit 101 proceeds to step S110 (jam detection).

[0069] <s110> If, in step S109 described above, some of the media transport sensors S are ON (S109-No), the initial control unit 101 determines that printing cannot continue because the state of the paper P has changed from before the cover was opened, such as by being partially slack or torn, detects a jam, and ends the series of processes.

[0070] <s111> On the other hand, after performing the normal initialization in step S108 described above, the print control unit 104 waits for reception of print data. When the print control unit 104 receives the print data (S111-Yes), the process proceeds to step S112.

[0071] <s112> The fixing control unit 106 starts the fixing warm-up.

[0072] <s113> The print control unit 104 starts printing when the fixing temperature reaches the target temperature.

[0073] <s114> On the other hand, if the advance warm-up of step S107 described above has been performed, the print control unit 104 determines whether print data has been received. Since the fixing warm-up is performed in parallel with the image initial process, if the print control unit 104 receives print data before the end of the initial process (image initial and fixing warm-up) (S114-Yes), it proceeds to step S115 at the same time as the end of the initial process. On the other hand, if the print control unit 104 has not received print data (S114-No), it proceeds to step S116.

[0074] <s115> The print control unit 104 starts printing.

[0075] <s116> The print control unit 104 judges whether a certain time has passed after the end of the initial process. If the certain time has passed (S116-Yes), the print control unit 104 proceeds to step S117.

[0076] <s117> If the certain period of time has elapsed (S116-Yes), the print control unit 104 ends the warm-up and returns to normal standby (the fixing unit 21 is at normal standby temperature).

[0077] (A-2-2) Pre-warm-up (details of step S107) FIG. 4 is a flowchart showing a characteristic operation (advance warm-up) of the printer according to this embodiment.

[0078] <s201> When the advance warm-up is started, the initial control unit 101 inquires of the consumables management unit 103 about information on replacement consumables.

[0079] <s202> The initial control unit 101 checks whether replacement of the photosensitive drum 32 has been detected as a result of inquiring to the consumables management unit 103. If the initial control unit 101 detects replacement of the photosensitive drum 32 (S202-Yes), the initial control unit 101 proceeds to step S203. On the other hand, if the initial control unit 101 does not detect replacement of the photosensitive drum 32 (S202-No), the initial control unit 101 proceeds to step S206.

[0080] <s203> When the initial control unit 101 detects replacement of the photosensitive drum 32 in the above-mentioned step S202 (S203-Yes), it judges whether or not the detected photosensitive drum 32 is a new one. When the photosensitive drum 32 is a new one, the initial control unit 101 proceeds to step S204. On the other hand, when the photosensitive drum 32 is not a new one (S203-No), it proceeds to step S205.

[0081] <s204> If the photoconductor drum 32 detected to have been replaced in step S203 is a new one (S203-Yes), the initial completion time predicting unit 102 calculates the expected initial time assuming that the initial I1 shown in FIG. 5 is executed.

[0082] <s205> In addition, if the photosensitive drum 32 detected to have been replaced in the above-mentioned step S203 is not new (S203-No), the initial completion time prediction unit 102 calculates the expected initial time assuming that the initial I2 shown in the above-mentioned Figure 5 is executed.

[0083] <s206> On the other hand, if the initial control unit 101 does not detect replacement of the photosensitive drum 32 in the above-mentioned step S202 (S202-No), it checks whether or not replacement of the toner cartridge 31 has been detected. If the initial control unit 101 detects replacement of the toner cartridge 31 (S206-Yes), it proceeds to step S207. On the other hand, if the initial control unit 101 does not detect replacement of the toner cartridge 31 (S206-No), it proceeds to step S209.

[0084] <s207> When the initial control unit 101 detects replacement of the toner cartridge 31 in the above-mentioned step S206 (S206-Yes), it checks whether the state before replacement was a toner low state or a toner empty state. When the state before replacement of the toner cartridge 31 was a toner low state or a toner empty state (S207-Yes), the initial control unit 101 proceeds to step S208. On the other hand, when the state before replacement of the toner cartridge 31 was not a toner low state or a toner empty state (S207-No), the initial control unit 101 proceeds to step S208.

[0085] <s208> If it is determined in the above-mentioned step S207 that the state of the toner cartridge 31 before replacement is a toner low state or a toner empty state (S207-Yes), the initial completion time prediction unit 102 calculates the predicted initial time assuming that the initial I3 shown in the above-mentioned Figure 5 will be executed.

[0086] <s209> Furthermore, if replacement of the toner cartridge 31 is not detected in the above-mentioned step S206 (S206-Yes) or if it is determined in the above-mentioned step S207 that the state of the toner cartridge 31 before replacement is not a toner low state or a toner empty state (S207-No), the initial completion time prediction unit 102 calculates the predicted initial time assuming that initial I4 shown in the above-mentioned Figure 5 is executed.

[0087] <s210> After calculating the predicted initial time, the initial control unit 101 requests the fixing control unit 106 to predict the warm-up time via the print control unit 104. The fixing control unit 106 acquires the current temperature 107 measured by the fixing temperature sensor 110.

[0088] <s211> The fixing control unit 106 obtains information about the paper P (paper P in a passing state) used in the previous printing (immediately before replacement) from the print medium storage unit 105. The target temperature 108 is determined based on the obtained information about the paper P.

[0089] <s212> The fixing control unit 106 obtains table information relating to the paper P used in the immediately preceding printing from the temperature rise table 109.

[0090] <s213> The fixing control unit 106 calculates the time required for warming up using the current temperature 107 and the target temperature 108 from the table information related to the paper P used in the immediately previous printing.

[0091] <s214> The initial control unit 101 subtracts the expected warm-up time from the expected initial time to calculate the timing for starting warm-up.

[0092] <s215> The initial control unit 101 starts initial processing (image initial processing) based on the confirmed initial contents.

[0093] <s216> After starting the image initial process, the initial control unit 101 issues a warm-up instruction to the fixing control unit 106 after the time calculated in step S214 has elapsed. In response to the instruction, the fixing control unit 106 starts the fixing warm-up.

[0094] (A-2-3) Secondary transfer roller separation operation during advance warm-up FIG. 8 is a flowchart showing the operations of the fixing warm-up and the image initial operation during the advance warm-up according to the embodiment.

[0095] <s301> When the advance warm-up in step S107 described above is started, the initial control unit 101 separates the transfer belt 33 from the secondary transfer roller 34 as shown in FIG.

[0096] <s302> After the separation is completed, the initial control unit 101 starts image initial (the above-mentioned step S215) at the previous printing speed.

[0097] <s303> After starting the image initial, the initial control unit 101 waits for the timing of starting the fixing warm-up calculated in the above-mentioned S214.

[0098] <s304> When it is time to start the fixing warm-up, the fixing control unit 106 starts the fixing warm-up at the lowest conveying speed. By warming up the fixing at a low conveying speed, it is possible to shorten the time it takes to reach the target temperature 108 and reduce the amount of paper P wasted by being conveyed during the warm-up.

[0099] <s305> After both the image initial process and the fixing warm-up process are completed, the transfer belt 33 and the secondary transfer roller 34 are nipped.

[0100] The subsequent process contents in FIG. 8 are similar to steps S114 to S117 in FIG. 3 described above, and therefore the description thereof will be omitted.

[0101] (A-3) Effects of the embodiment According to this embodiment, the following effects are obtained.

[0102] The initial control unit 101 (initial completion time prediction unit 102) estimates the time required for initial processing according to the consumables replaced when printing on paper P stopped due to the end of its life. In addition, the print control unit 104 (fixing control unit 106) estimates the time required for fixing warm-up required to resume the stopped printing, using the current fixing temperature (current temperature 107) and target temperature 108. By adjusting the start timing so that the image initial processing and fixing warm-up are completed at the same time and can be directly transferred to the printing operation, it is expected that paper waste will be reduced and printing will resume sooner.

[0103] In addition, as shown in FIG. 7 above, by separating the secondary transfer roller 34 from the transfer belt 33, the fixing warm-up speed, which was previously set to the initial speed, can be slowed down, thereby reducing paper waste and power consumption during warm-up.

[0104] (B) Other embodiments The present disclosure is not limited to the above-described embodiment, and may include modified embodiments as exemplified below.

[0105] (B-1) In step S215 described above, if the result of subtracting the expected warm-up time of the fixing unit 21 from the image initial processing time is 0 or less, the warm-up of the fixing unit 21 may be started simultaneously with the image initial processing.

[0106] (B-2) In the above embodiment, the printer 1 is an example of a color printer that uses toner of five colors, but it may also be a monochrome printer that uses only one color (black). [Explanation of symbols]

[0107] 1...printer, 10...paper supply section, 11...paper holding section, 12...guide roller, 14...cutter unit, 15...conveyor roller, 20...main body, 21...fixing section, 22...conveyor roller, 23...paper outlet, 30...image forming section, 31...toner cartridge, 32...photosensitive drum, 33...transfer belt, 34...secondary transfer roller, 101...initial control section, 102...initial completion time prediction section, 103...consumables management section, 104...print control section, 105...print media memory section, 106...fixing control section, 107...current temperature, 108...target temperature, 109...temperature rise table, 110...fixing temperature sensor, P...paper, R1, R2...conveyor path, S (S1 to S3)...media conveyance sensor.

Claims

1. An image forming apparatus for forming an image on a roll of paper transported along a paper path, comprising: an intermediate transfer member carrying a developer image; an image forming means for forming the developer image on the intermediate transfer body based on image data; a transfer means for transferring the developer image of the intermediate transfer body onto the roll paper; a fixing unit for fixing the developer image transferred by the transfer unit; an image forming control unit that controls an initial operation of the image forming means; a fixing control unit that calculates an expected time for a warm-up operation of the fixing unit based on medium information of the roll paper and a temperature of the fixing unit, and starts the warm-up operation of the fixing unit during the initial operation of the image forming unit so that the warm-up operation of the fixing unit is completed at the timing when the initial operation of the image forming unit is completed; The initial operation of the image forming unit and the warm-up operation of the fixing unit are performed in a state where the roll paper is passed through the paper passage.

1. An image forming apparatus comprising:

2. 2. The image forming apparatus according to claim 1, wherein a transport speed of the roll paper transported along the paper path during a warm-up operation of the fixing unit is slower than that during printing.

3. 3. The image forming apparatus according to claim 2, wherein the speed of forming the developer image by said image forming means during the initial operation and the speed of conveying the developer image by said intermediate transfer body are the same as those during printing.

4. 2. The image forming apparatus according to claim 1, wherein the image formation control section performs control to separate the transfer section from the intermediate transfer body before starting an initial operation by the image forming section.

5. 5. The image forming apparatus according to claim 1, wherein an initial operation by the image forming means and a warm-up of the fixing means are performed at the timing when the image forming means or a toner cartridge that supplies developer to the image forming means is replaced.

Images