JP2018120068A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible, in an electrophotographic printer, to protect a document to be read even when a conveyance path for the document and a conveyance path for a recording sheet to be printed are used in common.SOLUTION: When receiving a copying request from a user, an image forming apparatus does not immediately feed a document M to a conveyance path L1, but feeds the document M to the conveyance path L1 after a surface of a photoreceptor drum 121 as an image carrier is cleaned and a recording sheet P is conveyed to the conveyance path L1, and when the temperature of a fixing part 13 is not reduced to a predetermined threshold or lower, prevents conveyance of the document M to the conveyance path L1.SELECTED DRAWING: Figure 1

Description

  The present invention particularly relates to an electrophotographic image forming apparatus.

  In a printer having a scanner function, in Patent Documents 1 and 2 below, a document conveyance path to be read (scanner target) and a print target (print target) are disclosed in order to realize downsizing of the apparatus. It describes that the recording paper conveyance path is shared.

  In addition, there are various printer printing methods such as an inkjet method and an electrophotographic method. A general electrophotographic printer charges a photoconductor as an image carrier having no charge (charging process), and irradiates a charged photoconductor surface with laser light based on a document. Then, a latent image of the original is formed on the surface of the photoconductor (exposure process), the latent image is visualized with toner (development process), and the toner image formed by the visualization is formed on the recording paper at the transfer unit. The process consists of five processes: transfer (transfer process), and fix the transferred toner image onto the recording paper at the fixing unit (fixing process).

Japanese Patent Laid-Open No. 2006-016201 Japanese Patent Laid-Open No. 06-054140

  Since the inventions described in Patent Documents 1 and 2 are assumed to be ink jet printers, in the electrophotographic printers as in the inventions described in Patent Documents 1 and 2, the reading target Assuming that a technique for sharing the original document conveyance path and the recording paper conveyance path to be printed is adopted, the following problems are expected to occur when the original is read.

  The first problem is that there is a risk that document smear will occur when the document is passed through a transfer nip for toner image transfer formed by the image carrier and the transfer unit.

  A second problem is that the original may be shrunk by passing the original through a fixing nip formed by a high-temperature fixing unit.

  The third problem is that the transport path of an electrophotographic printer tends to be complicated, and therefore there is a risk that a paper jam (jam) will occur when the document is transported and the document will be damaged.

  The present invention has been made in view of the above circumstances, and in an electrophotographic image forming apparatus, even if a conveyance path of a document to be read and a conveyance path of a recording sheet to be printed are shared, The object is to reduce document damage.

  An image forming apparatus according to one aspect of the present invention includes a paper feeding unit that stores recording paper and feeds the recording paper, an image carrier, and a transfer unit. A toner image is formed on a surface of the image carrier. And forming an image on the recording paper by transferring the toner image onto the recording paper fed by the paper feeding unit at a transfer nip formed by the image carrier and the transfer unit. A fixing unit that fixes the toner image transferred to the recording paper to the recording paper at a fixing nip portion formed by a heating roller and a pressure roller; and the recording paper on which the toner image is fixed by the fixing unit is discharged. A discharge tray, a conveyance path for conveying the recording paper from the paper feeding unit to the discharge tray through the fixing unit, a manual feed tray, and a document placed on the manual feed tray to the conveyance path. With the feeding section to send An image reading sensor provided at a position facing the conveyance path, a document reading unit that reads an image of a document conveyed on the conveyance path, and image data obtained by reading by the document reading unit A control unit that controls the image forming unit to form an image on the recording paper fed by the paper feeding unit, and an operation accepting unit that accepts a user operation. If the copy execution condition is satisfied, the control unit causes the feeding unit to feed the document placed on the manual feed tray to the conveyance path, and the document reading unit To read an image of the document conveyed on the conveyance path, to cause the sheet feeding unit to feed the recording paper to the conveyance path, and to feed the image forming unit to the image feeding unit. Images on the recording paper The copy execution conditions are set in advance so that the surface of the image carrier is cleaned, the recording paper is transported to the transport path, and the temperature of the fixing unit is lower than the temperature at the time of image formation. This is at least one of being equal to or less than a predetermined first threshold value.

  In addition, an image forming apparatus according to one aspect of the present invention includes a paper feeding unit that stores recording paper and feeds the recording paper, an image carrier, and a transfer unit, and a toner is provided on a surface of the image carrier. An image that forms an image on the recording paper by transferring the toner image onto the recording paper fed by the paper feeding unit at a transfer nip formed by the image carrier and the transfer unit. A forming unit; a fixing unit that fixes the toner image transferred to the recording paper to the recording paper at a fixing nip portion formed by a heating roller and a pressure roller; and the recording paper on which the toner image is fixed by the fixing unit. A paper discharge tray, a transport path for transporting the recording paper from the paper feed unit to the discharge tray through the fixing unit, a manual feed tray, and a document placed on the manual feed tray. Salary to be sent to An image reading sensor provided on the opposite side of the conveyance path, a document reading section that reads an image of a document conveyed on the conveyance path, and image data obtained by reading by the document reading section And a control unit that forms an image on the recording paper fed by the paper feeding unit by controlling the image forming unit, and an operation receiving unit that accepts a user operation, and a plurality of the discharge trays are provided. The transport path is branched in the direction of each of the discharge trays, and further includes a branching member for distributing the transport direction of the document at a branch point of the transport path, and the operation reception unit receives a copy request from the user. The control unit controls the driving of the branch member to place the branch member at a predetermined position, and the path to the discharge tray is the most curved. It is an small predetermined path of.

  According to the present invention, even in an electrophotographic image forming apparatus in which a conveyance path of a document to be read and a conveyance path of recording paper to be printed are shared, damage to the document can be reduced. Is possible.

1 is a schematic side sectional view showing a structure of an image forming apparatus according to a first embodiment of the present invention. FIG. 2 is a schematic side cross-sectional view showing a photosensitive drum and its peripheral part constituting an image forming apparatus. FIG. 2 is a functional block diagram schematically illustrating a main internal configuration of the image forming apparatus according to the first embodiment. 5 is a flowchart illustrating an example of a copy process performed by the image forming apparatus 1 according to the first embodiment. 5 is a flowchart illustrating an example of a copy process performed by the image forming apparatus 1 according to the first embodiment. 10 is a flowchart illustrating an example of a copy process performed by the image forming apparatus 1 according to the second embodiment. It is the figure which showed an example of the operation screen displayed on a display part.

  Embodiments of an image forming apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side sectional view showing the structure of the image forming apparatus according to the first embodiment of the present invention. FIG. 2 is a schematic side cross-sectional view showing the photosensitive drum and its peripheral portion constituting the image forming apparatus.

  The image forming apparatus 1 is, for example, a printer having both a scanner function and a copy function. The apparatus main body 11 includes a document reading unit 5, a sheet feeding unit 14, an image forming unit 12, a fixing unit 13, a top discharge tray 151, and a rear discharge tray. A discharge tray 152 and a manual feed tray 161 are included. The rear discharge tray 152 and the manual feed tray 161 are configured to be openable and closable.

  The paper feed unit 14 is provided at the bottom of the apparatus main body 11, and includes a paper feed cassette 141 for storing a plurality of recording papers P, and a recording paper pickup for taking out the recording papers P stored in the paper feed cassette 141 one by one. A roller 142 and a paper feed roller pair 143 that feeds the recording paper P taken out by the recording paper pickup roller 142 to the transport path L1.

  The recording paper P fed by the paper feed roller pair 143 is sent out to the transport path L1 through the transport drum 171. The recording paper P delivered to the transport path L1 is supplied to the image forming unit 12 by the registration roller pair 172. Note that the registration roller pair 172 and the roller driving unit 156 (FIG. 3) that supplies rotational driving force to the registration roller pair 172 are also examples of the “conveyance path” in the claims.

  The manual feed tray 161 is provided in front of the apparatus main body 11 and places the document M thereon. The originals M placed on the manual feed tray 161 are taken out one by one by the original pickup roller 162, and the originals M taken out by the original pickup roller 162 are sent out to the transport path L1 by the feeding roller 163. That is, the conveyance path of the document M to be read is shared with the conveyance path of the recording paper P to be printed. The document pickup roller 162 and the feeding roller 163, and the roller driving unit 156 (FIG. 3) for supplying rotational driving force thereto are examples of the feeding unit in the claims.

  The document reading unit 5 includes a document reading sensor provided at a position facing the conveyance path L1, and reads an image of the document M conveyed on the conveyance path L1. An example of the document reading sensor is a CIS (Contact Image Scanner).

  The image forming unit 12 is provided above the paper feed cassette 141 and includes a photosensitive drum 121, a charging device 122, an exposure device 123, a developing device 124, a transfer roller 125, and a cleaning device 60.

  The photosensitive drum 121 is an image carrier and is configured to be rotatable about a rotation axis. The charging device 122 includes a charging roller 1221 (FIG. 2) and charges the surface of the photosensitive drum 121. The exposure device 123 forms a latent image on the surface of the photosensitive drum 121 by irradiating laser light based on the image data of the document M read by the document reading unit 5.

  The developing device 124 includes a developing roller 1241 and visualizes the latent image formed on the surface of the photosensitive drum 121 with toner. The transfer roller 125 transfers the toner image formed on the photosensitive drum 121 to the recording paper P at the transfer nip portion N1 formed with the photosensitive drum 121. The transfer roller 125 is an example of a transfer unit in the claims.

  The cleaning device 60 includes a cleaning roller 61 (FIG. 2) and a cleaning blade 62 (FIG. 2). The cleaning roller 61 and the cleaning blade 62 are in contact with the surface of the photosensitive drum 121 to remove toner and deposits remaining on the surface of the photosensitive drum 121 and clean the surface of the photosensitive drum 121. The cleaning roller 61 and the cleaning blade 62 are examples of the cleaning member in the claims.

  The fixing unit 13 fixes the toner image on the recording paper P by thermocompression bonding, and includes a heating roller 131 including a heat lamp 132 as a heat source, and a pressure roller 133. The heating roller 131 and the pressure roller 133 make a pair, and when the recording paper P is nipped and conveyed by the fixing nip N2 by the heating roller 131 and the pressure roller 133, an unfixed toner image is generated by the heat of the heat lamp 132. It is melted and fixed on the recording paper P by the pressure of the heating roller 131 and the pressure roller 133. A fixing thermistor 134 for detecting the temperature of the fixing unit 13 is provided near the heating roller 131. The fixing thermistor 134 is an example of a temperature detection unit in the claims.

  A flap 153 for distributing the recording paper P and the document M in the transport direction is provided at a branch point of the transport path L1 located downstream of the fixing nip portion N2 in the transport direction of the recording paper P and the document M. The flap 153 is configured to be rotatable about the rotation shaft 154 by a rotational driving force supplied from a flap driving unit 155 described later. Depending on the position of the flap 153, the recording paper P and the original M are conveyed in the direction of the top discharge tray 151 or in the direction of the rear discharge tray 152. The flap 153 is an example of a branch member in the claims.

  A case where double-sided printing is performed in the image forming apparatus 1 will be described. The recording paper P on which an image is formed on one side by the image forming unit 12 is sandwiched between the discharge roller pair 159, then switched back by the discharge roller pair 159 and sent to the reverse conveyance path L2. It is conveyed to the conveyance path L1 by the conveyance drum 171 and is supplied again to the image forming unit 12 by the registration roller pair 172. Thus, an image can be formed on the other side of the recording paper P.

  Further, a first recording paper sensor 181 is provided at a position upstream of the transfer nip portion N1 in the conveyance direction of the recording paper P and the original M and facing the conveyance path L1, and the recording paper P than the fixing nip portion N2. In addition, a second recording paper sensor 182 is provided on the downstream side in the conveyance direction of the document M and at a position facing the conveyance path L1. The first recording paper sensor 181 and the second recording paper sensor 182 include, for example, a light emitting unit and a light receiving unit, and can detect the recording paper P and the original M that are conveyed on the conveyance path L1. Yes.

  FIG. 3 is a functional block diagram schematically showing the main internal configuration of the image forming apparatus 1. The image forming apparatus 1 includes a control unit 10, a document reading unit 5, an image forming unit 12, an image memory 32, an HDD (Hard Disk Drive) 92, a fixing unit 13, a paper feeding unit 14, an operation unit 47, a fixing thermistor 134, The flap drive unit 155 includes a first recording paper sensor 181 and a second recording paper sensor 182. Components similar to those of the image forming apparatus 1 shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted here.

  The image memory 32 is an area for temporarily storing image data of the document M obtained by reading by the document reading unit 5 and temporarily storing image data to be printed by the image forming unit 12. It is. The HDD 92 is a large-capacity storage device that stores image data and the like read by the document reading unit 5.

  The operation unit 47 receives instructions such as an image forming operation execution instruction and a document reading operation execution instruction from the operator regarding various operations and processes that can be executed by the image forming apparatus 1. The operation unit 47 includes a display unit 473 that displays operation guidance to the operator. The display unit 473 is a touch panel, and the operator can operate the image forming apparatus 1 by touching buttons and keys displayed on the screen.

  The flap drive unit 155 includes a motor, a gear, a driver, and the like, and functions as a drive source that applies a rotational drive force to the rotary shaft 154 that forms the flap 153.

  The roller driving unit 156 includes a motor, a gear, a driver, and the like, and is rotationally driven by a pair of registration rollers 172, other transport e-rollers disposed in the transport paths L1 and L2, the document pickup roller 162, and the feed roller 163. It functions as a driving source that applies force.

  The control unit 10 includes a processor, a RAM (Random Access Memory), a ROM (Read Only Memory), and a dedicated hardware circuit. The processor is, for example, a central processing unit (CPU), an application specific integrated circuit (ASIC), or a micro processing unit (MPU). The control unit 10 includes a control unit 100 and an operation reception unit 101.

  The control unit 10 functions as the control unit 100 and the operation reception unit 101 by the operation of the processor according to the control program stored in the HDD 92. However, the control unit 100 and the like can be configured by a hardware circuit regardless of the operation of the control unit 10 according to the control program. The same applies to each embodiment unless otherwise specified.

  The control unit 100 governs overall operation control of the image forming apparatus 1. The control unit 100 includes a document reading unit 5, an image forming unit 12, an image memory 32, an HDD 92, a fixing unit 13, a paper feeding unit 14, an operation unit 47, a fixing thermistor 134, a flap driving unit 155, and a first recording paper sensor 181. , And the second recording paper sensor 182 to perform drive control and the like of these units.

  The operation receiving unit 101 receives an operation input from the user via the operation unit 47. For example, the operation reception unit 101 receives a copy request from the user.

  Next, copy processing performed in the image forming apparatus 1 according to the first embodiment will be described based on the flowcharts shown in FIGS. 4 and 5. This copy process is performed when the operation reception unit 101 receives a copy request (here, single-sided reading of a document) from the user.

  When the operation accepting unit 101 accepts a copy request from the user, the control unit 100 controls the drive of the flap driving unit 155 and rotates the flap 153 around the rotation shaft 154 so that the flap 153 It is arranged at a predetermined first position (here, a horizontal orientation; a position indicated by a broken line in FIG. 1) so that the recording paper P and the document M are conveyed in the direction of the rear discharge tray 152 ( S1).

  When the image forming apparatus 1 is configured as shown in FIG. 1, the path to the rear discharge tray 152 is less curved and has a straight path than the path to the top discharge tray 151 ( In other words, the control unit 100 arranges the flap 153 at a position where the flap 153 is horizontally oriented in S1.

  Subsequently, the control unit 100 rotates the photosensitive drum 121 and removes toner and deposits adhering to the surface of the photosensitive drum 121 with the cleaning roller 61 and the cleaning blade 62 for a predetermined time Tm. By doing so, the surface of the photosensitive drum 121 is cleaned (S2), and then the control unit 100 causes the paper supply unit 14 to feed the recording paper P to the transport path L1 (S3). However, it is determined whether or not the recording paper P is discharged to the rear discharge tray 152 (S4).

  For example, the control unit 100 discharges the recording paper P to the rear discharge tray 152 based on the time elapsed from the time when the second recording paper sensor 182 detects the trailing edge of the recording paper P as measured by a built-in timer. It is determined whether or not.

  When the control unit 100 determines that the recording paper P has been discharged to the rear discharge tray 152 (YES in S4), the temperature T of the fixing unit 13 indicated by the information obtained from the fixing thermistor 134 is a predetermined first threshold value. It is determined whether or not T1 (for example, 100 ° C.) or less (S5). The first threshold value T1 is a temperature having a predetermined value lower than a predetermined fixing appropriate temperature TA (for example, 180 to 200 ° C.) that is used when the fixing unit 13 forms an image.

  When the control unit 100 determines that the temperature T of the fixing unit 13 is equal to or lower than the first threshold T1 (YES in S5), the document pickup roller 162 causes the document M placed on the manual feed tray 161 to be taken out. Then, the roller driving source 156 is driven and controlled, and the document M is fed to the transport path L1 by the feeding roller 163 and the document pickup roller 162 (S11).

  Thereafter, the control unit 100 determines whether or not the document M fed to the transport path L1 exists (S12). For example, the control unit 100 determines that the document M exists when the first recording paper sensor 181 detects the leading edge of the document M. Further, the control unit 100 measures in advance the time from the start of the drive control for the document pickup roller 162 and the feeding roller 163 measured by the built-in timer until the first recording paper sensor 181 detects the leading edge of the document M. If the predetermined time has elapsed, it is determined that the document M does not exist on the transport path L1.

  When the control unit 100 determines that there is no document M fed to the conveyance path L1 (NO in S12), no document M is placed on the manual feed tray 161, or the manual feed tray 161 is loaded. Since the document M is not properly placed, the control unit 100 causes the display unit 473 to display a display screen indicating that there is no document placed on the transport path L1 (S13). Thereafter, the processing operation is terminated.

  On the other hand, when the control unit 100 determines that the document M fed to the transport path L1 exists (YES in S12), the control unit 100 causes the document reading unit 5 to read the image of the document M transported on the transport path L1. Image data obtained by reading by the document reading unit 5 is stored in the image memory 32 (S14).

  Subsequently, the control unit 100 causes the document pickup roller 162 to take out the next document M placed on the manual feed tray 161, and causes the feeding roller 163 to feed the document M taken out by the document pickup roller 162 to the transport path. L1 is fed (S15), and the control unit 100 determines whether or not there is a document M fed to the transport path L1 (that is, whether or not there is a document M to be read next). (S16).

  When the control unit 100 determines that there is a document M fed to the conveyance path L1 (that is, there is a document M to be read next) (YES in S16), the process returns to S14 to read the document. The unit 5 is caused to read an image of the document M conveyed on the conveyance path L1.

  On the other hand, when the control unit 100 determines that the document M fed to the conveyance path L1 does not exist (NO in S16), all the documents M placed on the manual feed tray 161 are fed to the conveyance path L1. As a result, the control unit 100 determines whether or not the final document M placed on the manual feed tray 161 has been discharged to the rear discharge tray 152 (S17).

  When the document M to be discharged to the rear discharge tray 152 is not the final document, the second recording paper sensor 182 detects the leading edge of the next document M in a relatively short time from when the trailing edge of the document M is detected. Will be detected. In other words, when the second recording paper sensor 182 detects the trailing edge of the document M and does not detect the leading edge of the next document M even after a while, the final document M is It is determined that the paper is discharged to the rear discharge tray 152. That is, for example, the control unit 100 measures the final document M on the rear discharge tray 152 based on the passage of time from the time when the second recording paper sensor 182 detects the trailing edge of the document M, as measured by a built-in timer. It is determined whether or not it has been discharged.

  When it is determined that the final document M has been discharged to the rear discharge tray 152 (YES in S17), the control unit 100 supplies power to the heat lamp 132 to warm the heating roller 131 (S18), and the control unit 100 Then, it is determined whether or not the temperature T of the fixing unit 13 indicated by the information obtained from the fixing thermistor 134 is equal to or higher than the proper fixing temperature TA (for example, 180 to 200 ° C.) (S19). As described above, the first threshold T1 is set to be lower than the proper fixing temperature TA.

  When the control unit 100 determines that the temperature T is equal to or higher than the proper fixing temperature TA (YES in S19), the control unit 100 controls the driving of the flap driving unit 155, and the flap 153 is centered on the rotation shaft 154. , The flap 153 is placed at a predetermined second position (here, the downward position), and the recording paper P is conveyed in the direction of the top discharge tray 151 (S20). The control unit 100 causes the paper feeding unit 14 to feed the recording paper P to the conveyance path L1, and is conveyed to the conveyance path L1 based on the image data stored in the image memory 32 by the image forming unit 12. An image is formed on the recording paper P (S21). Then, this processing operation ends.

  According to the first embodiment, even if a copy is requested by the user, the document M is not immediately fed to the conveyance path L1, and if the copy execution condition is not satisfied, the document M is fed to the conveyance path L1. Not. The copy execution conditions include that the surface of the photosensitive drum 121 is cleaned, the recording paper P is transported to the transport path L1, and the temperature T of the fixing unit 13 is equal to or lower than the first threshold T1. It is included.

  That is, the document M is fed to the transport path L1 on the condition that the surface of the photosensitive drum 121 is cleaned, the recording paper P is transported to the transport path L1, and the fixing unit 13 is not at a high temperature. This is the case.

  When the surface of the photoconductive drum 121 is cleaned, the toner and deposits adhering to the surface are removed and the surface becomes clean, so that the original smudge generated by passing the original M through the transfer nip portion N1. Can reduce the risk.

  When the recording paper P is transported to the transport path L1, the toner and adhering matter adhering to the transport path L1 (including the surface of the photosensitive drum 121) can be rubbed against the recording paper P, so The fear can be reduced. Further, in order to transport the recording paper P to the transport path L1, the recording paper P passes through the nip portion N2 of the fixing unit 13 so that the fixing unit 13 (heating roller 131 and pressure roller 133) inside the apparatus main body 11 is used. The effect of cooling the temperature and the effect of being able to confirm beforehand with the recording paper P before feeding the document M to the transport path L1 are also provided.

  When the fixing unit 13 is at a high temperature, the original M is shrunk by passing the original M through the fixing nip N2, but when the fixing unit 13 is at a high temperature, the original M is not fed to the transport path L1. It is possible to reduce the risk of document shrinkage caused by passing the document through the fixing nip N2.

  Accordingly, the document M is fed to the transport path L1 when the surface of the photosensitive drum 121 and the transport path L1 are in a clean state. When the fixing unit 13 is hot, the document M is transported by the transport path. Since the paper is not fed to L1, even if the transport path of the original M and the transport path of the recording paper P are made common, it is possible to prevent the original M from becoming dirty and the original M from being shrunk. Can protect from breakage.

  Further, when a copy request from the user is received, the flap 153 is set to the first position (a horizontal position) so that the path of the document M is the path with the least bending (that is, the path where paper jam is unlikely to occur). Since they are arranged, the possibility of document damage due to paper jams can be reduced.

  In the first embodiment, the case where the document M is discharged from the rear discharge tray 152 is described. However, in another embodiment, the control unit 100 controls the directions of the top discharge tray 151 and the rear discharge tray 152, respectively. The number of occurrences of jamming is counted, the direction in which jamming is unlikely to occur is detected based on the number of occurrences of jamming, and the position of the flap 153 is controlled so that the direction in which jamming is unlikely becomes the path of the document M. The document M may be discharged from the top discharge tray 151 or from the rear discharge tray 152.

  For example, the control unit 100 causes the original M to be discharged from the top discharge tray 151 at the beginning of use of the image forming apparatus 1, but the number of jam occurrences in the direction of the top discharge tray 151 is set to a predetermined number. Upon arrival, the document M may be changed to be discharged from the rear discharge tray 152.

  In the first embodiment, the case where the recording paper P is fed to the transport path L1 after cleaning the surface of the photosensitive drum 121 has been described. In another embodiment, the control unit 100 includes Before the surface of the photosensitive drum 121 is cleaned, the sheet feeding unit 14 feeds the recording sheet P1 to the conveyance path L1, and the recording sheet P is sandwiched by the transfer nip portion N1. The surface of the photoconductive drum 121 may be cleaned by rotating the drum 121 and rubbing the toner or adhering material adhering to the surface of the photoconductive drum 121 against the recording paper P.

  When the operation accepting unit 101 accepts a copy request for double-sided reading of a document from the user, the control unit 100 controls the driving of the flap driving unit 155 and initially sets the flap 153 to the second position (a position facing downward). ), The recording paper P is conveyed in the direction of the top discharge tray 151, and once sent to the reverse conveyance path L2 by the switchback by the discharge roller pair 159. Thereafter, the drive of the flap drive unit 155 is controlled, and the flap 153 is The recording paper P may be discharged from the rear discharge tray 152 by being arranged at the first position (position facing horizontally). Thereby, it is possible to confirm in advance with the recording paper P whether paper jam occurs not only in the transport path L1 but also in the reverse transport path L2.

  In the first embodiment, when the control unit 100 determines that the final document M has been discharged to the rear discharge tray 152 (YES in S17), power is supplied to the heat lamp 132 and the heating roller 131 is turned on. Although the case of heating is described, as another embodiment, the processing of S17 is deleted, and the control unit 100 feeds all the originals M placed on the manual feed tray 161 to the conveyance path L1. That is, it is determined that the leading edge of another document M in the transport direction is not detected within a predetermined period after the first recording paper sensor 181 detects the trailing edge of the document M in the transport direction. At that time (NO in S16), power is supplied to the heat lamp 132 to heat the heating roller 131 so that the temperature T of the fixing unit 13 can reach the fixing proper temperature TA quickly. It may be.

  If the image of the final document M is being read, the final document M will soon pass through the fixing nip portion N2, so even if the fixing unit 13 starts warming at this time, The degree of damage is considered minor. Therefore, in such a case, by starting the heating of the fixing unit 13, the start time of the image forming operation in the copy process can be shortened, and the productivity can be increased.

  In the first embodiment, the copy execution conditions are as follows: (i) the surface of the photosensitive drum 121 is cleaned, (ii) the recording paper P is transported to the transport path L1, and (iii) When all of the fact that the temperature of the fixing unit 13 is equal to or lower than the first threshold value T1 lower than the temperature at the time of image formation is satisfied, the control unit 100 performs the processing after S11. ) To (iii) when at least one of the conditions is satisfied, the processing after S11 may be performed.

  Next, an example of copy processing by the image forming apparatus 1 according to the second embodiment will be described based on the flowchart shown in FIG. This processing operation is performed when the operation reception unit 101 receives a copy request (here, single-sided reading of a document) from the user.

  For example, the operation reception unit 101 displays the operation screen D1 on which the selection buttons B1 and B2 are formed as illustrated in FIG. 7 on the display unit 473, thereby setting whether to give priority to the copy processing speed. Accept from the user in advance. The selection button B1 is marked with “Yes”, the selection button B2 is marked with “No”, and when the operation accepting unit 101 accepts an operation on the selection button B1, it accepts an instruction to prioritize the copy processing speed. When an operation for the selection button B2 is received, an instruction not to give priority to the copy processing speed is received and stored.

  When the operation accepting unit 101 accepts a copy request from the user, the control unit 100 controls the drive of the flap driving unit 155 and rotates the flap 153 around the rotation shaft 154 so that the flap 153 The recording paper P and the original M are arranged in the first position (a horizontal position) so that the transport direction of the recording paper P and the original M is the direction of the rear discharge tray 152 (S31).

  Subsequently, the control unit 100 determines whether or not to give priority to the copy processing speed, that is, whether or not a processing speed priority request is received from the user, based on the contents received in advance by the operation receiving unit 101. (S32).

  When the control unit 100 determines not to give priority to the copy processing speed (NO in S32), the control unit 100 causes the paper supply unit 14 to feed the recording paper P1 to the transport path L1 (S33). In a state where the recording paper P is sandwiched between the transfer nips N1, the photosensitive drum 121 is rotated, and the toner and the adhering matter adhering to the surface of the photosensitive drum 121 are rubbed against the recording paper P. The surface of 121 is cleaned (S34), and it is determined whether or not the recording paper P is discharged to the rear discharge tray 152 (S35).

  When the control unit 100 determines that the recording paper P has been discharged to the rear discharge tray 152 (YES in S35), the control unit 100 determines in advance the temperature T of the fixing unit 13 indicated by the information obtained from the fixing thermistor 134. It is determined whether or not the first threshold value T1 (for example, 100 ° C.) or less is set (S36).

  When the control unit 100 determines that the temperature T of the fixing unit 13 is equal to or lower than the first threshold T1 (YES in S36), the process proceeds to S11 in FIG. 5 and the control unit 100 is placed on the manual feed tray 161. The control for feeding the document M is started.

  On the other hand, if the control unit 100 determines in S32 that priority is given to the copy processing speed (YES in S32), the control unit does not feed the recording paper P1 to the paper feed path L1 in the paper feed unit 14. 100 rotates the photosensitive drum 121 and removes toner and deposits adhered to the surface of the photosensitive drum 121 with the cleaning roller 61 and the cleaning blade 62, thereby cleaning the surface of the photosensitive drum 121 ( S37).

  Subsequently, the control unit 100 determines whether or not the temperature T of the fixing unit 13 indicated by the information obtained from the fixing thermistor 134 is equal to or lower than a predetermined second threshold T2 (for example, 120 ° C.) (S38). ). The second threshold value T2 is set to a value higher than the first threshold value T1. That is, the control unit 100 employs the second threshold T2 that is higher by a predetermined amount (20 ° C. in the present embodiment) than the case where the processing speed priority request is not accepted as the first threshold T1.

  When the control unit 100 determines that the temperature T of the fixing unit 13 is equal to or lower than the second threshold T2 (YES in S38), the process proceeds to S11 in FIG. 5 and the control unit 100 is placed on the manual feed tray 161. The control for feeding the document M is started.

  According to the second embodiment, when the user desires to give priority to the copy processing speed, the surface of the photosensitive drum 121 is cleaned without sandwiching the recording paper P by the transfer nip portion N1, and the cleaning is performed. Therefore, the threshold for determining the temperature T of the fixing unit 13 is also changed to the second threshold T2 higher than the first threshold T1.

  That is, when a request to prioritize the copy processing speed is received from the user, the copy execution condition is relaxed, so that the start time of the copy process can be advanced and the productivity can be improved.

  If the user wants to give priority to the copy processing speed, the original to be scanned may be less important so that it may be smudged or shrunk, or it may be blank or similar. It is done. For example, when the importance of the first document to be read is low and may be soiled or shrunk, the first document is transported to the transport path L1 so that the transport path L1 becomes dirty. Can be removed, and the fixing unit 13 can be removed by heat, and the second and subsequent originals can be conveyed along the clean conveyance path L1.

  In addition, when the processing speed priority request from the user is received by the operation receiving unit 101 (YES in S32), the control unit 100 performs when the processing speed priority request is not received in S37. The cleaning operation simplified for a predetermined stroke may be performed rather than the cleaning operation on the surface of the photosensitive drum 121. The cleaning operation simplified for a predetermined stroke is, for example, a cleaning operation in which the cleaning time by the cleaning device 60 is half the time Tm.

  The present invention is not limited to the configuration of the above embodiment, and various modifications can be made. In the above embodiment, a printer is used as an embodiment of the image forming apparatus according to the present invention. However, this is merely an example. For example, other image forming having a scanner function and a printer function is possible. It may be a device.

  Moreover, in the said embodiment, the structure and process which were shown by the said embodiment using FIG. 1 thru | or FIG. 7 are only one Embodiment of this invention, and are not the meaning which limits this invention to the said structure and process.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 5 Document reading part 12 Image forming part 13 Fixing part 14 Paper feed part 60 Cleaning apparatus 61 Cleaning roller 62 Cleaning blade 100 Control part 101 Operation reception part 121 Photosensitive drum 125 Transfer roller 131 Heating roller 133 Pressure roller 151 Top Discharge tray 152 Rear discharge tray 153 Flap 161 Manual feed tray L1 Conveying path M Original N1 Transfer nip N2 Fixing nip P Recording paper

Claims (8)

A paper feeding unit for containing the recording paper and feeding the recording paper;
An image carrier and a transfer unit; and a toner image is formed on the surface of the image carrier, and the paper feeding unit feeds the toner image at a transfer nip formed by the image carrier and the transfer unit. An image forming unit that forms an image on the recording paper by transferring it to the recording paper,
A fixing unit for fixing the toner image transferred to the recording paper to the recording paper at a fixing nip portion by a heating roller and a pressure roller;
A discharge tray for discharging the recording paper on which the toner image is fixed by the fixing unit;
A transport path for transporting the recording paper from the paper feed unit to the discharge tray through the fixing unit;
A bypass tray,
A feeding unit that feeds the document placed on the manual feed tray to the conveyance path;
An original reading unit that has an image reading sensor provided at a position facing the conveying path, and reads an image of an original conveyed on the conveying path;
A control unit configured to form an image on the recording paper fed by the paper feeding unit by controlling the image forming unit based on image data obtained by reading by the document reading unit;
An operation reception unit for receiving user operations,
When the operation accepting unit accepts a copy request from the user,
When the copy execution condition is satisfied, the control unit causes the feeding unit to feed the document placed on the manual feed tray to the conveyance path, and the document reading unit conveys the conveyance path. Causing the image of the original to be read, causing the paper feeding unit to feed the recording paper to the conveyance path, causing the image forming unit to form an image on the recording paper fed by the paper feeding unit,
The copy execution conditions are determined in advance such that the surface of the image carrier is cleaned, the recording paper is transported to the transport path, and the temperature of the fixing unit is lower than the temperature at the time of image formation. An image forming apparatus that is at least one of being equal to or less than a first threshold value. A cleaning device having a cleaning member that contacts the surface of the image carrier and removes toner adhering to the surface;
When the copy execution condition is that the surface of the image carrier is cleaned, when the operation reception unit receives a copy request from a user,
The control unit rotates the image carrier that rotates about a rotation axis about the rotation axis, and causes the cleaning member to remove the toner adhering to the surface of the image carrier. The image forming apparatus according to claim 1, wherein the surface of the image carrier is cleaned. When the copy execution condition is that the surface of the image carrier is cleaned, when the operation reception unit receives a copy request from a user,
The control unit causes the paper feeding unit to feed the recording paper to the conveyance path, and the image carrier rotates around a rotation axis in a state where the recording paper is sandwiched by the transfer nip part. The image forming apparatus according to claim 1, wherein the surface of the image carrier is cleaned by rotating a body around the rotation axis and rubbing the toner adhering to the surface of the image carrier against the recording paper. apparatus. A temperature detection unit for detecting the temperature of the fixing unit;
When the copy execution condition is that the operation receiving unit receives a copy request from a user when the temperature of the fixing unit is equal to or lower than the first threshold value,
The control unit determines whether the temperature of the fixing unit indicated by the information detected by the temperature detection unit is equal to or lower than the first threshold value, and the temperature of the fixing unit is equal to or lower than the first threshold value. The image forming apparatus according to claim 1, wherein if it is determined, it is determined that the copy execution condition is satisfied. When the operation accepting unit accepts a processing speed priority request that prioritizes the processing speed of copying from the user,
The image forming apparatus according to claim 4, wherein the control unit employs a second threshold value that is higher by a predetermined amount than the first threshold value used when the processing speed priority request is not accepted. When the copy execution condition is that the surface of the image carrier is cleaned, the operation reception unit receives a processing speed priority request from the user to prioritize the copy processing speed.
2. The control unit according to claim 1, wherein the operation for cleaning the surface of the image carrier is simplified by a predetermined stroke as compared with a case where the processing speed priority request is not accepted. The image forming apparatus described. When the copy execution condition is that the temperature of the fixing unit is equal to or lower than the first threshold value,
2. The image forming apparatus according to claim 1, wherein the control unit starts heating the fixing unit to return to a temperature at the time of image formation when the document reading unit starts reading an image of a document to be a final page. . A paper feeding unit for containing the recording paper and feeding the recording paper;
An image carrier and a transfer unit; and a toner image is formed on the surface of the image carrier, and the paper feeding unit feeds the toner image at a transfer nip formed by the image carrier and the transfer unit. An image forming unit that forms an image on the recording paper by transferring it to the recording paper,
A fixing unit for fixing the toner image transferred to the recording paper to the recording paper at a fixing nip portion by a heating roller and a pressure roller;
A discharge tray for discharging the recording paper on which the toner image is fixed by the fixing unit;
A transport path for transporting the recording paper from the paper feed unit to the discharge tray through the fixing unit;
A bypass tray,
A feeding unit that feeds the document placed on the manual feed tray to the conveyance path;
An original reading unit that has an image reading sensor provided on the opposite side of the conveying path and reads an image of an original conveyed on the conveying path;
A control unit configured to form an image on the recording paper fed by the paper feeding unit by controlling the image forming unit based on image data obtained by reading by the document reading unit;
An operation reception unit for receiving user operations,
A plurality of the discharge trays are provided;
The transport path is branched in the direction of each of the discharge trays,
A branching member for distributing the transport direction of the document at a branch point of the transport path;
When the operation accepting unit accepts a copy request from the user,
The control unit controls driving of the branching member, arranges the branching member at a predetermined position, and sets the path to the discharge tray as a predetermined path with the least bending.