Document feeder, image reading device, and image forming apparatus

Abstract

To suppress the repeated occurrence of a jam when documents stick to each other.SOLUTION: An image forming apparatus includes a separation roller pair 206 that forms a separation nip 206a for separating documents stacked on a document tray 201 one by one and feeds the document in a feeding direction, and a separation sensor 209 that detects the document on a downstream side of the separation nip, and includes a control unit that stops feeding of the document when the separation sensor does not detect the document until a predetermined time elapses after feeding of the document by a separation feeding unit is started. In a case where the environmental sensor unit 313 acquires at least one of temperature and humidity and the acquired environmental information satisfies a predetermined condition, the display 91 displays a screen for prompting the user to loosen the document bundle.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a document transport device that transports documents, and an image reading device and an image forming device that include the same. [Background technology]

[0002] Image forming devices such as copiers, facsimile machines, and multifunction devices are equipped with an image reading device that reads an image from a document. Some image reading devices are equipped with an automatic document feeder (hereinafter referred to as an "ADF: Auto Document Feeder") to continuously read multiple documents. Such image forming devices are capable of reading the image of a document while transporting the document using the ADF.

[0003] An ADF separates multiple documents into individual sheets and transports them. However, if the documents stick together due to factors such as static electricity, the documents cannot be separated and a paper jam may occur. In response to this, Patent Document 1 proposes an ADF equipped with a multi-feed sensor that detects multi-fed documents. The ADF described in Patent Document 1 displays a screen on the operation unit that prompts the user to separate the documents when the multi-feed sensor detects a multi-feed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-52593 Summary of the Invention [Problem to be solved by the invention]

[0005] However, depending on the environment (temperature and humidity) in which the device is installed, many documents may stick together, preventing the documents from being fed from the document tray. In such cases, the device will determine that a jam has occurred before the documents reach the multi-feed sensor. Therefore, even if feeding is started again in that state, the documents will not be stuck together, resulting in repeated jams.

[0006] Therefore, an object of the present invention is to provide a document transport device, an image reading device, and an image forming device that can prevent repeated jams when documents stick together. [Means for solving the problem]

[0007] One aspect of the present invention is a document transport device comprising: a document tray on which documents are loaded; a separation and feeding unit that forms a separation nip to separate the documents loaded on the document tray one by one and feeds the documents separated at the separation nip in a feeding direction; a detection sensor that detects documents downstream of the separation nip in the feeding direction; a control unit that stops the feeding of the documents by the separation and feeding unit if the detection sensor does not detect the documents within a predetermined time after the separation and feeding unit starts feeding the documents; an environment acquisition unit that acquires environmental information including at least one of temperature and humidity; and a display unit that displays information to a user; wherein when the control unit stops feeding of the documents based on the detection sensor, if the environmental information acquired by the environment acquisition unit satisfies a predetermined condition, the display unit displays a predetermined screen that prompts the user to sort the document stack; and if the environmental information acquired by the environment acquisition unit does not satisfy the predetermined condition, the display unit does not display the predetermined screen.

[0008] Another aspect of the present invention is a document transport device comprising: a document tray on which documents are loaded; a separation feeding unit that forms a separation nip that separates the documents loaded on the document tray one by one and feeds the documents separated by the separation nip in a feeding direction; a detection sensor that detects documents downstream of the separation nip in the feeding direction; a control unit that stops the feeding of the documents by the separation feeding unit if the detection sensor does not detect the documents within a predetermined time after the separation feeding unit starts feeding the documents; and a display unit that displays information to a user, wherein the display unit displays a predetermined screen that prompts the user to sort the document stack if the feeding of the documents based on the detection sensor is stopped a threshold number of times in succession. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a document transport device, an image reading device, and an image forming device that can prevent repeated jams when documents stick together. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. [Figure 2] FIG. [Figure 3] FIG. [Figure 4] FIG. 2 is a front view of an operation unit of the image reading device. [Figure 5] FIG. 1 is a block diagram of an image forming apparatus. [Figure 6] 6 is a flowchart showing the flow of skimming control by the reader controller according to the first embodiment. [Figure 7] 5 is a flowchart showing the flow of skimming control by the system controller according to the first embodiment. [Figure 8] FIG. 1A is a diagram showing an example of a condition for determining that an environment is prone to document sticking, and FIG. 1B is a diagram showing another example of a condition for determining that an environment is prone to document sticking. [Figure 9] 10 is an example of an operation screen when entering a job. [Figure 10] 10 is an example of a jam release screen when a jam occurs. [Figure 11] An example of the document handling screen when a jam occurs. [Figure 12] An example of the document reload screen when a jam occurs. [Figure 13] 10 is a flowchart showing the flow of skimming control by a reader controller according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

[0012] [First embodiment] <Image forming device> 1 is a diagram showing the configuration of an image forming apparatus equipped with an image reading apparatus according to this embodiment. The image forming apparatus 1001 has an image reading apparatus 1005 mounted on a printer 1001A, which is the apparatus main body, and is realized by, for example, a copier, facsimile machine, multifunction machine, MFP (Multi Function Peripheral), etc. The image forming apparatus 1001 has an operation unit 90, which will be described later, as a user interface including an input interface and an output interface.

[0013] The image reading device 1005 includes a scanner unit 100 and an ADF 200 that automatically transports an original D. The ADF 200 is an example of an original transport device. The ADF 200 is attached to the scanner unit 100 so as to be able to open and close freely. The scanner unit 100 reads an image from the original D by optically scanning the original D. The image reading device 1005 transmits image data representing the read image of the original D to a control unit 1032 of the printer 1001A. Under the control of the control unit 1032, the printer 1001A forms an image based on the acquired image data on a sheet S, which is a recording medium. That is, the printer 1001A can form an image on the sheet S based on the image of the original D read by the image reading device 1005.

[0014] The printer 1001A includes an image forming unit 1033 that forms an image on a sheet S, a sheet feeding unit 1006 that feeds the sheet S to the image forming unit 1033, and a fixing unit 1029. The sheet S is transported from the sheet feeding unit 1006 to the image forming unit 1033, where an image is transferred onto the sheet S. Thereafter, the image is fixed by the fixing unit 1029, and the sheet S is discharged onto a discharge tray 1030.

[0015] The sheet feeding unit 1006 has a plurality of sheet storage units 1037a, 1037b, 1037c, and 1037d, each capable of storing sheets S of different sizes. The sheets S stored in each of the sheet storage units 1037a, 1037b, 1037c, and 1037d are fed from the sheet storage units 1037a, 1037b, 1037c, and 1037d by the corresponding pickup rollers 1002a, 1002b, 1002c, and 1002d. The fed sheets S are separated one by one by the corresponding feed rollers 1003a, 1003b, 1003c, and 1003d and retard rollers 1004a, 1004b, 1004c, and 1004d, and conveyed to the corresponding conveying roller pairs 1031. The sheet S is transferred in order to a plurality of pairs of conveying rollers 1031 arranged along the sheet conveying path, and is then conveyed to a pair of registration rollers 1036 provided on the sheet conveying path.

[0016] The sheet feeding unit 1006 also includes a manual feed tray 1037e. A sheet S placed on the manual feed tray 1037e by a user is fed into the printer 1001A by a feed roller 1038 and conveyed to a pair of registration rollers 1036.

[0017] The pair of registration rollers 1036 corrects the skew by stopping the leading edge of the sheet S. The pair of registration rollers 1036 resumes conveying the sheet S to the image forming unit 1033 in accordance with the progress of the toner image formation process by the image forming unit 1033.

[0018] The image forming unit 1033 of this embodiment is an electrophotographic device equipped with a photosensitive drum 1021. Note that the image forming unit 1033 may be configured to form images by, for example, an inkjet method or an offset printing method.

[0019] The photosensitive drum 1021 is a drum-shaped photosensitive body having a photosensitive layer on its surface, and is rotatable around a drum axis along the conveyance direction of the sheet S. A charger 1018, an exposure unit 1023, a developing unit 1024, a transfer charger 1025, a separation charger 1026, and a cleaner 1027 are arranged around the photosensitive drum 1021. The charger 1018 uniformly charges the surface of the photosensitive drum 1021. The exposure unit 1023 exposes the charged surface of the photosensitive drum 1021 to light based on image data acquired from the image reading device 1005 or an external device, and forms an electrostatic latent image on the photosensitive drum 1021.

[0020] The developing unit 1024 contains a two-component developer containing toner and carrier. The developing unit 1024 supplies charged toner to the photosensitive drum 1021 to cause it to adhere to the electrostatic latent image. This develops the electrostatic latent image, forming a toner image on the surface of the photosensitive drum 1021. The toner image carried on the photosensitive drum 1021 is transferred to the sheet S by a bias electric field formed by a transfer charger 1025. The sheet S is transported from a registration roller pair 1036 to the transfer charger 1025 in accordance with the timing at which the toner image is formed.

[0021] The sheet S onto which the toner image has been transferred is separated from the photosensitive drum 1021 by a bias electric field formed by a separation charger 1026, and is transported to a fixing device 1029 by a pre-fixing transport section 1028. Note that any deposits such as residual toner that have not been transferred to the sheet S and remain on the photosensitive drum 1021 are removed by a cleaner 1027. This allows the photosensitive drum 1021 to prepare for the next image forming operation.

[0022] The fixing device 1029 sandwiches and conveys the sheet S between a pair of rollers. At this time, the fixing device 1029 heats and presses the sheet S to melt and fix the toner image on the sheet S. Fixation of the toner image completes image formation on the sheet S. The sheet S on which the image has been formed is discharged via a pair of discharge rollers 1010 to a discharge tray 1030 that protrudes outward from the printer 1001A.

[0023] When double-sided printing is performed, the sheet S, on which an image has been formed on one side (first side), passes through the fixing device 1029 and is then conveyed to an inverting section 1039 in order to form an image on the other side (second side). The sheet S has its image-forming side inverted from the first side to the second side by the inverting section 1039, and is conveyed to a double-sided conveying section 1040. The double-sided conveying section 1040 conveys the sheet S, on which the image-forming side has been inverted, to a pair of registration rollers 1036. The sheet S is conveyed from the pair of registration rollers 1036 to an image forming section 1033, where an image is formed on the second side, and is then discharged to an output tray 1030.

[0024] The printer 1001A also has an environmental sensor unit 313. The environmental sensor unit 313 is an environmental acquisition unit that acquires environmental information about the surrounding environment in which the image forming apparatus 1001 is installed. The environmental sensor unit 313 includes a temperature sensor 313a and a humidity sensor 313b (described later) and is capable of acquiring the temperature and humidity of the environment in which the apparatus is installed. The printer 1001A can control the image formation conditions of the image forming unit based on the environmental information acquired by the environmental sensor unit 313. For example, the printer 1001A controls the fixing temperature of the fixing unit 1029 based on the environmental sensor unit 313. This enables image formation under appropriate image formation conditions according to the environmental conditions around the image forming apparatus 1001. However, the environmental sensor unit only needs to have at least one of the temperature sensor 313a and the humidity sensor 313b and be able to acquire environmental information including at least one of temperature and humidity.

[0025] <Image reader> 2 is a perspective view of the appearance of the image reading device 1005. The ADF 200 is attached to the scanner unit 100 by hinges 132a and 132b so as to be able to open and close freely. In FIG. 2, the ADF 200 is in an open state relative to the scanner unit 100. The scanner unit 100 has a built-in controller, which will be described later. The controller controls the operation of the image reading device 1005.

[0026] 3 is a configuration diagram of an image reading device 1005. The scanner unit 100 has a document glass table 101, a front surface scanning glass 105, and a white reference plate 104 on its upper surface, and incorporates a front surface reading unit 103 and a moving guide 102. The front surface reading unit 103 reads an image on one side (front surface) of a document. The front surface reading unit 103 can be moved in the sub-scanning direction (left and right direction in FIG. 3) along the moving guide 102 by an optical motor described below.

[0027] When reading an original D transported by the ADF 200, the front surface reading unit 103 stops below the front surface flow reading glass 105 and performs an image reading process by reading the image of the transported original D line by line. The process of reading an original D while it is being transported by the ADF 200 is called "flow reading." When reading an original placed on the original platen glass 101, the front surface reading unit 103 performs an image reading process by reading the image of the original D line by line while moving along the movement guide 102 in the sub-scanning direction. The process of reading an original placed on the original platen glass 101 is called "fixed reading." The white reference plate 104 is read by the front surface reading unit 103 when performing shading correction of the front surface reading unit 103. The white reference plate 104 is provided between the original platen glass 101 and the front surface flow reading glass 105.

[0028] The ADF 200 includes a document tray 201 on which sheet-like documents D are stacked. The ADF 200 is a sheet transport device that transports the documents D to a reading position where the scanner unit 100 reads an image from the documents D. The ADF 200 transports the documents D placed on the document tray 201 to a paper output tray 220 via a transport path. A plurality of documents D can be placed on the document tray 201. The document tray 201 includes two side regulating plates 201a in a direction perpendicular to the transport direction of the documents D. The two side regulating plates 201a are movable in the width direction perpendicular to the transport direction, and sandwich the documents D placed on the document tray 201 between them to regulate the movement of the documents D in the direction perpendicular to the transport direction. In the following description, upstream and downstream are based on the transport direction of the documents D, with the source of the documents D being upstream and the destination of the documents D being downstream.

[0029] The ADF 200 can transport the originals D one by one in succession to the transport path. The transport path is provided with various rollers for transporting the originals D and various sensors for detecting the originals D. The transport path has, as a separation mechanism, a pair of separation rollers 206 that prevents the originals D from protruding from the original tray 201 and advancing downstream before transport begins, and a pickup roller 205. The original tray 201 is provided with an original detection sensor 204 for detecting the presence or absence of the originals D on the original tray 201.

[0030] The pickup roller 205 drops onto the top of a stack of documents D stacked on the document tray 201 and rotates, thereby feeding the topmost document D in the feeding direction. The separation roller pair 206 forms a separation nip 206a that separates the documents, and separates and transports the topmost document D fed by the pickup roller 205. The documents are separated using a known separation technique. For example, the documents are separated by rotating the two rollers of the separation roller pair 206 in opposite directions. The pickup roller 205 and the separation roller pair 206 are driven by the same drive source. The separation roller pair 206 transports the document D to the pull-out roller pair 207. The pickup roller 205 and the separation roller pair 206 are an example of a separation and feeding unit that separates documents and feeds them in the feeding direction. The separation and feeding unit is not limited to rollers such as the pickup roller 205 and the separation roller pair 206, and may be composed of other rotating members such as a belt. The separation roller pair 206 may also be configured with a separation pad that forms a separation nip 206a together with the roller.

[0031] A separation sensor 209 is disposed downstream of the separation roller pair 206 in the feeding direction. When the separation sensor 209 detects the leading edge of the document D, the pair of pull-out rollers 207 starts conveying the document D, and the rotation of the pickup roller 205 and the pair of separation rollers 206 is stopped. Specifically, the document D is conveyed a predetermined distance after the separation sensor 209 detects the leading edge of the document D, and when the document D reaches the pair of pull-out rollers 207, the rotation of the pickup roller 205 and the pair of separation rollers 206 is stopped. Thereafter, the document D is conveyed in this order by the pair of pull-out rollers 207, the pair of conveying rollers 210, and the pair of upstream lead rollers 211. Note that the pair of conveying rollers 210 may perform skew correction of the document D, similar to the pair of registration rollers 1036. The pair of upstream lead rollers 211 conveys the document D onto the front-surface scanning glass 105.

[0032] A multi-feed sensor 221 is disposed downstream of the separation roller pair 206. Multi-feeding is a phenomenon in which two documents pass through the separation nip 206a together while remaining stuck together. When multi-feeding occurs, abnormalities such as document skipping or jamming occur. The multi-feed sensor 221 is an ultrasonic sensor composed of an ultrasonic transmitter and an ultrasonic receiver disposed across the conveyance path. When a document D passes through the multi-feed sensor 221, the multi-feed sensor 221 emits ultrasonic waves toward the document D. The multi-feed sensor 221 receives the ultrasonic waves that have passed through the document D, and can detect whether or not the document D has been multi-fed based on the intensity of the received ultrasonic waves. When the multi-feed sensor 221 detects a multi-feed of documents, the CPU 301 (described later) stops feeding the document D. In this embodiment, the multi-feed sensor 221 is disposed between the pull-out roller pair 207 and the conveyance roller pair 210 in the conveyance direction. However, the double feed sensor 221 may be disposed downstream of the separation nip 206 a of the separation roller pair 206 , for example, between the separation roller pair 206 and the pull-out roller pair 207 .

[0033] A lead sensor 212 is disposed upstream of the front surface scanning glass 105. When reading the front surface of the original D, the front surface reading unit 103 starts reading the original D based on the timing when the lead sensor 212 detects the leading edge of the original D. Note that an original holder 213 is provided on the front surface scanning glass 105. The original D is read by the front surface reading unit 103 while passing between the front surface scanning glass 105 and the original holder 213. The position of the front surface scanning glass 105 is the reading position by the front surface reading unit 103.

[0034] The document D that has passed the reading position of the front side reading unit 103 is transported by the lead downstream roller pair 214. A back side scanning glass 217 is provided downstream of the lead downstream roller pair 214. A back side scanning unit 216 for reading an image on the other side (back side) of the document is provided at a position facing the transport path across the back side scanning glass 217. When the document D is transported between the back side scanning glass 217 and the transport path by the lead downstream roller pair 214, the back side scanning unit 216 reads the image on the back side. When reading the back side of the document D, the back side scanning unit 216 starts reading the document D based on the timing when the lead sensor 212 detects the leading edge of the document D. The position of the back side scanning glass 217 is the reading position when reading the back side.

[0035] The document D, whose back side image has been read, is discharged to the discharge tray 220 by the discharge roller pair 219. Note that if only the front side image is read, the image reading process by the back side reading unit 216 is not performed, and the document D passes through the reading position of the back side reading unit 216 and is discharged to the discharge tray 220 after the image reading process by the front side reading unit 103. A paper discharge sensor 218 is disposed between the back side flow reading glass 217 and the discharge roller pair 219. If the document D is not present on the document tray 201, based on the timing at which the discharge sensor 218 detects the rear end of the document D, after the document D has been discharged, the rollers for transporting the fed document D stop rotating. That is, the pull-out roller pair 207, the transport roller pair 210, the lead upstream roller pair 211, the lead downstream roller pair 214, and the discharge roller pair 219 stop rotating.

[0036] In this embodiment, the front side reading unit 103 and the back side reading unit 216 have the same configuration. Both the front side reading unit 103 and the back side reading unit 216 include a light emitting unit, an optical system such as a lens array, and a light receiving unit. In this embodiment, the light emitting unit is an LED (Light Emitting Diode), and the light receiving unit is a line sensor. The line sensor is realized by, for example, a CIS (Contact Image Sensor) or a CCD (Charge Coupled Device) configured with a reduction optical system using a mirror. The line sensor is arranged in the width direction of the document. Therefore, for the front side reading unit 103 and the back side reading unit 216, the width direction of the document is the main scanning direction, and the transport direction of the document is the sub-scanning direction.

[0037] The front surface reading unit 103 uses an LED to irradiate light onto the original D passing over a front surface flow reading glass 105 (front surface reading position). The light irradiated from the LED is reflected by the surface of the original D. The light reflected by the surface of the original D is imaged on the light receiving surface of the line sensor by the optical system. The line sensor outputs image data representing an image of the front surface of the original D in accordance with the reflected light that has been imaged. In this way, the front surface reading unit 103 performs image reading processing on the front surface of the original D.

[0038] The back surface reading unit 216 performs image reading processing when double-sided reading of the original D is set. The back surface reading unit 216 uses an LED to irradiate light onto the original D passing through a back surface flow reading glass 217 (back surface reading position). The light irradiated from the LED is reflected by the back surface of the original D. The light reflected by the back surface of the original D is imaged on the light receiving surface of the line sensor by the optical system. The line sensor outputs image data representing an image of the back surface of the original D in accordance with the reflected light that has been imaged. In this way, the back surface reading unit 216 performs image reading processing of the back surface of the original D. Note that the front surface reading unit 103 and the back surface reading unit 216 may have different configurations.

[0039] <Operation section> Next, the operation unit 90 of the image forming apparatus 1001 will be described. FIG. 4 is a top view of the operation unit 90. The operation unit 90 is arranged on the front side of the scanner unit 100 and accepts operations from the user. The operation unit 90 is composed of a display 91 as a display unit that displays information to the user, a keypad 92 consisting of multiple hard keys, a start button 93, etc. The display 91 not only displays information to the user but also functions as a touch panel that the user can operate by touching it with their fingers. The user can issue various instructions and settings, such as an instruction to start scanning and print settings, via the operation unit 90.

[0040] <controller> 5 is a diagram showing the configuration of the controller of image reading device 1005. The controller (controller) is made up of reader controller 300 and system controller 320. Reader controller 300 is provided in scanner unit 100. System controller 320 is provided in scanner unit 100 or printer 1001A. Reader controller 300 and system controller 320 are communicatively connected by command data bus 330 and image data bus 331.

[0041] The reader controller 300 is an information processing device including a CPU (Central Processing Unit) 301, a ROM (Read Only Memory) 302, and a RAM (Random Access Memory) 303. The CPU 301 controls the overall operation of the image reading device 1005 by executing a computer program stored in the ROM 302. The RAM 303 provides a working area for the CPU 301 when it executes processing. The CPU 301 is connected to an image memory 304 and an image processing unit 305.

[0042] The CPU 301 is connected to motors, sensors, the front surface reading unit 103, and the back surface reading unit 216 arranged in various parts of the image reading device 1005. The motors include a separation motor 310, a transport motor 311, and an optical motor 312. The separation motor 310 is a drive source for rotating the pickup roller 205 and the separation roller pair 206 to feed the original D one sheet at a time to the transport path. The transport motor 311 is a drive source for each roller for transporting the original D to the transport path, such as the pull-out roller pair 207, the transport roller pair 210, the lead upstream roller pair 211, the lead downstream roller pair 214, and the discharge roller pair 219. The optical motor 312 is a drive source for moving the front surface reading unit 103 along the movement guide 102. The sensors include a document detection sensor 204, a separation sensor 209, a lead sensor 212, a paper discharge sensor 218, and a double feed sensor 221.

[0043] The motors, sensors, front-side reading unit 103, and back-side reading unit 216 operate as described above. CPU 301 stores image data output from front-side reading unit 103 and back-side reading unit 216 in image memory 304. In response to an image output request received from system controller 320 via command data bus 330, CPU 301 performs various image processes on the stored image data in image processing unit 305 and transmits the processed image data to system controller 320 via image data bus 331. Furthermore, CPU 301 notifies system controller 320 via image data bus 331 of a vertical synchronization signal that serves as a reference for the leading edge of the read image and a horizontal synchronization signal that serves as a reference for the leading edge of one line of pixels in the read image, in accordance with the timing of reading the original.

[0044] The system controller 320 is an information processing device including a CPU 321, a ROM 322, a RAM 323, an image processing unit 324, and an image memory 325. The image processing unit 324 includes an image area separation unit 328. The CPU 321 is communicably connected to the CPU 301 of the reader controller 300 via a command data bus 330, and cooperates with the CPU 301 to send and receive data related to image reading processing. The CPU 321 is also connected to the operation unit 90 described above, and is capable of receiving operations from the user.

[0045] The CPU 321 transmits an image output request to the reader controller 300. In response to the image output request, the CPU 321 performs various image processing operations on the image data acquired from the reader controller 300 via the image data bus 331 using the image processing unit 324. The image data after the image processing is stored in the image memory 325. The image area separation unit 328 performs image area separation processing when storing the image data after the image processing in the image memory 325.

[0046] Image area separation processing is performed as follows. The image area separation unit 328 detects areas where characters are formed (text areas) and areas where graphics other than text are formed (picture areas) from the image represented by the image data. The text areas and picture areas are combined to form the content areas where the content of the document D is formed. The image processing unit 324 performs image processing with different settings for each area based on the detected content areas, thereby enabling appropriate image processing to be performed on the content of the image data. The image area separation processing is performed using known image area separation techniques.

[0047] The CPU 321 is also connected to the control unit 1032 of the printer 1001A via a system bus 332. The control unit 1032 is also connected to the above-mentioned environmental sensor unit 313. Specifically, the control unit 1032 is connected to a temperature sensor 313a that detects temperature and a humidity sensor 313b that detects humidity. The control unit 1032 controls the image formation conditions of the image forming unit 1033 based on a signal from the environmental sensor unit 313. The CPU 301 of the reader controller 300 can also receive environmental information acquired by the environmental sensor unit 313 via the command data bus 330. This allows the CPU 301 to control the image reading device 1005 based on the environmental information acquired by the environmental sensor unit 313.

[0048] <Scanning Control> Next, the control of skimming in this embodiment will be described. Fig. 6 is a flowchart illustrating the flow of operations of the reader controller 300 when skimming is performed. The flowchart in Fig. 6 is executed by the CPU 301 when the user issues a skimming start instruction (a reading start instruction, a copy start instruction) via the operation unit 90.

[0049] When CPU 301 receives the skim reading start command, CPU 301 performs a reading preparation process such as setting the reading resolution and color mode and performing shading processing (S101). Here, CPU 321 notifies CPU 301 of the detected values ​​(temperature and humidity values) of environment sensor unit 313 acquired via control unit 1032 along with the skim reading start command. When the reading preparation process is complete, CPU 301 starts driving separation motor 310 and transport motor 311 to start feeding the original (S102). At this time, as separation motor 310 is driven, pickup roller 205 descends onto the top surface of the original, and feeding of the original begins.

[0050] Next, CPU 301 starts monitoring separation sensor 209 (S103). If separation sensor 209 is OFF (S103N), that is, if the document has not yet reached separation sensor 209, CPU 301 compares the separation and conveyance distance from the start of paper feed with a preset jam detection distance (S111). In S111, CPU 301 monitors whether a separation jam has occurred. If the separation and conveyance distance from the start of paper feed is longer than the jam detection distance, CPU 301 determines that a separation jam has occurred. If the separation and conveyance distance from the start of paper feed is shorter than the jam detection distance, CPU 301 again monitors whether separation sensor 209 is ON. In other words, CPU 301 repeatedly monitors separation sensor 209 until separation sensor 209 is turned ON in S103 or the separation and conveyance distance from the start of paper feed exceeds the jam detection distance in S111.

[0051] If the separation sensor 209 turns ON in S103 before the separation and conveyance distance from the start of paper feed exceeds the jam detection distance in S111 (S103Y), the CPU 301 stops the separation motor 310 to stop paper feed. At this time, feeding of the next document is stopped, but the conveyance motor 311 continues to convey documents that have already been separated.

[0052] Thereafter, CPU 301 starts monitoring lead sensor 212 (S105). If lead sensor 212 is OFF (S105N), i.e., if the document has not yet reached lead sensor 212, CPU 301 compares the lead transport distance since separation sensor 209 turned ON with a preset jam detection distance (S119). In S119, CPU 301 monitors whether a lead jam has occurred. If the lead transport distance since separation sensor 209 turned ON is longer than the jam detection distance, CPU 301 determines that a lead jam has occurred. If the lead transport distance since separation sensor 209 turned ON is less than the jam detection distance, CPU 301 again monitors whether lead sensor 212 is ON. In other words, CPU 301 repeatedly monitors lead sensor 212 until lead sensor 212 turns ON in S105 or the lead transport distance since separation sensor 209 turned ON in S119 exceeds the jam detection distance. The jam detection distance in S119 is different from the jam detection distance in S111.

[0053] If the lead sensor 212 turns ON in S105 before the lead transport distance after the separation sensor 209 turns ON in S119 exceeds the jam detection distance (S105Y), the CPU 301 starts the document reading process and transfer process (S106). In S106, the CPU 301 reads images on both sides of the document using the front side reading unit 103 and the back side reading unit 216. Then, the CPU 301 transfers the read image data from the image processing unit 305 to the image processing unit 324.

[0054] Thereafter, CPU 301 checks the reading status from image processing unit 305 and waits for notification of the end of reading (S107). After reading is completed (S107Y), CPU 301 checks document detection sensor 204 (S108), and if there is a next document (S108N), drives separation motor 310 again (S102) and starts feeding the next document. If there is no next document (S108Y), CPU 301 drives conveyance motor 311 a predetermined distance as a paper discharge process and then stops it (S109), and then notifies CPU 321 of the end of reading (S110) and ends skimming control.

[0055] The above-described processing from S102 to S110 is processing when no jam has occurred. Next, processing when a jam has occurred will be described. If the separation and conveyance distance from the start of paper feed exceeds the jam detection distance in S111, CPU 301 determines that a separation jam has occurred and stops separation motor 310 and conveyance motor 311 to stop the conveyance of the original. That is, if separation sensor 209 does not detect an original until a predetermined time has elapsed since the start of paper feed, CPU 301 determines that a separation jam has occurred and stops the feeding of the original. Next, CPU 301 performs a document sticking determination (S113). Details of the document sticking determination will be described later, but in S113, CPU 301 determines whether or not there is a possibility that multiple documents are stuck together based on environmental information acquired by environmental sensor unit 313.

[0056] Thereafter, if the environmental information acquired by the environmental sensor unit 313 satisfies the conditions that make it easy for documents to stick together, the CPU 301 notifies the CPU 321 of separation jam notification 2 (S115), and if the conditions are not satisfied, the CPU 301 notifies the CPU 321 of separation jam notification 1 (S116). Here, separation jam notification 1 and separation jam notification 2 are both information notifying that a jam has occurred in the separation unit of the ADF 200, but separation jam notification 1 and separation jam notification 2 are different notifications. Specifically, separation jam notification 2 is a notification when it is highly likely that the jam has occurred due to documents sticking together, while separation jam notification 1 is a notification when it is highly likely that the jam has occurred due to a cause other than documents sticking together. Possible causes of jams other than documents sticking together include, for example, so-called rough setting, in which documents are fed without being properly set in the document tray 201.

[0057] After the separation jam notification in S115 or S116, CPU 301 checks the status of separation sensor 209 and lead sensor 212, monitors whether any documents remain in the conveyance path, and waits for all sensors to turn OFF (S117). If all documents have been removed by the user and both separation sensor 209 and lead sensor 212 have turned OFF (S117Y), CPU 301 notifies CPU 321 of jam release (S118) and ends skimming control.

[0058] Furthermore, if the read transport distance after separation sensor 209 turns ON in S119 exceeds the jam detection distance, CPU 301 determines that a read jam has occurred and stops transport motor 311 to stop transport of the document. Then, CPU 301 sends a read jam notification to CPU 321 (S121). Here, the read jam notification is information notifying that a jam has occurred downstream of the separation unit. After the read jam notification, processing proceeds to S117 described above, and when the jam is cleared, skimming control ends.

[0059] <Document sticking detection process> Next, the document sticking determination process of S113 will be described with reference to Fig. 8. Fig. 8(a) is a diagram showing an example of a condition for determining that the environment is prone to document sticking. In Fig. 8(a), the gray area indicates a condition in which the document is prone to sticking. Specifically, when the temperature is equal to or higher than the first temperature T L or less and the humidity is the first humidity H L The following region and the temperature are at a second temperature T H or more and the humidity is the second humidity H H The above-mentioned areas are conditions under which the document is likely to stick.

[0060] In the process of determining whether the original is stuck, the CPU 301 acquires environmental information from the environmental sensor unit 313. As shown in FIG. 8(a), when both the temperature and humidity are equal to or lower than the first threshold value (first temperature T L , the first humidity H L ) or below a second threshold (second temperature T H , second humidity H H), CPU 301 determines that the state is such that the original is likely to stick. In other states, CPU 301 determines that the state is not such that the original is likely to stick. In other words, if both the temperature and humidity are equal to or lower than the first threshold or equal to or higher than the second threshold, CPU 301 notifies CPU 321 of separation jam notification 2 (S115), and in other states, CPU 301 notifies CPU 321 of separation jam notification 1 (S116).

[0061] Furthermore, the determination of conditions under which a document is likely to stick is not limited to this. Fig. 8(b) is a diagram showing another example of conditions under which an environment is determined to be one in which document sticking is likely to occur. In Fig. 8(b), the gray area also indicates conditions under which a document is likely to stick. Specifically, conditions under which a document is likely to stick are areas where the temperature and humidity are below boundary 1 and areas above boundary 2.

[0062] Here, the linear equation of boundary 1 is expressed as follows: t=-A L ×h+B L t indicates temperature, h indicates humidity, and A L and B L is a predetermined constant. In this case, if the temperature and humidity are Tx and Hx, respectively, it is determined that the document is likely to stick when the following conditions are met: Tx+A L ×Hx≦B L Also, the linear equation for boundary 2 is expressed as follows: t=-A H ×h+B H Again, A H and B H is a predetermined constant. In this case, if the temperature and humidity are Tx and Hx, respectively, it is determined that the document is likely to stick when the following conditions are met: Tx+A H ×Hx≧B H In this way, when the environmental information acquired by the environment sensor unit 313 satisfies a predetermined condition, the CPU 301 determines that the conditions are such that the document is likely to stick. Note that, although an example has been described in which the CPU 301 determines whether the conditions are such that the document is likely to stick based on both the temperature and humidity, the present invention is not limited to this. The CPU 301 may also determine whether the conditions are such that the document is likely to stick based on only one of the temperature and humidity. For example, the predetermined condition under which the CPU 301 determines that the document may stick is when the temperature is equal to or exceeds a first temperature T L Similarly, the predetermined condition may be only one condition that the humidity is equal to or less than a first humidity H L Hereinafter, the temperature is the second temperature T H Above, the humidity is the second humidity H H The predetermined condition may be, for example, that the temperature is equal to or higher than the first temperature T L or less and the humidity is the first humidity H L Any two of these conditions may be satisfied as follows: In this way, it is preferable that the predetermined conditions be set arbitrarily based on the characteristics of the device.

[0063] <UI control when jam occurs> Next, the system control in this embodiment will be described with reference to Fig. 7. Fig. 7 is a flowchart illustrating the flow of operations of the system controller 320 in the skimming control of this embodiment, which is executed by the CPU 321.

[0064] 9 to 12 show screens displayed on the display 91 of the operation unit 90. FIG. 9 is a job input screen that is displayed before a job starts. FIG. 10 is a jam release screen for prompting the user to remove documents when a jam occurs, and a message prompting the user to remove the documents is displayed. FIG. 11 is a document handling screen that is displayed when separation jam notification 2 is notified, and a message prompting the user to separate the documents before placing them in document tray 201 is displayed. The document handling screen of FIG. 11 is an example of a predetermined screen that prompts the user to separate the documents. FIG. 12 is a document reset screen that is displayed when separation jam notification 1 is notified, and a message prompting the user to place the documents in document tray 201 is displayed. These two screens differ in that the document handling screen of FIG. 11 displays a message prompting the user to separate the documents, but the document reset screen of FIG. 12 does not display a message prompting the user to separate the documents. In this embodiment, "sorting documents" means unraveling and separating a stack of documents, which is achieved, for example, by turning over the stack of documents to create air between the documents.

[0065] Before skimming begins, the operation unit 90 displays the job input screen shown in Fig. 9. The job input screen displays soft keys such as a read color specification button B101, a resolution specification button B102, a magnification specification button B103, a document size specification button B104, an operation mode specification button B105, and a start button B106. The user can input any settings related to document image reading on this job input screen. After completing the settings, when the user presses the start button B106, the CPU 321 starts skimming control.

[0066] When the CPU 321 recognizes that a skim reading command has been input from the operation unit 90, it notifies the CPU 301 of the start of the skim reading process (S201). At this time, the CPU 321 notifies the CPU 301 of the operation mode selected by the user in addition to the settings required for reading, such as the reading color designation, resolution, and document size, which the user has set from the operation unit 90.

[0067] Thereafter, CPU 321 waits for a notification from CPU 301 (S202). Here, the notification from CPU 301 refers to information transmitted from CPU 301 to CPU 321, such as the image data of the document scanned in S106 of FIG. 6 or the skimming completion notification in S110. Upon receiving a notification from CPU 301 (S202Y), CPU 321 checks the notification content (S203). If the notification content is document image data (S203N), CPU 321 executes image output processing, such as printing the scanned image or storing it in ROM as an image file, based on the user's instruction input at the start of the job (S204). Thereafter, CPU 321 returns to monitoring the notification from CPU 301 (S202). If the notification content is a skimming completion notification (S203Y), the result of the skimming completion notification is checked (S205). If the scanning result is normal (S205Y), skimming control ends. Here, a normal reading result means that the image of the document has been read without a jam occurring and the flow reading control has ended.

[0068] If the result of the skim-reading completion notification indicates a jam (S205N), CPU 321 displays the jam release screen shown in FIG. 10 on operation unit 90 (S206) and prompts the user to remove any documents remaining in ADF 200. Thereafter, CPU 321 again monitors notifications from CPU 301 and waits for a jam release notification (S207). Upon receiving a jam release notification from CPU 301, CPU 321 checks the jam notification content notified at the end of skim-reading (S208). Here, the jam notification checked by CPU 321 is either separation jam notification 2 in S115 of FIG. 6, separation jam notification 1 in S116, or read jam notification in S121.

[0069] If the content of the jam notification is separation jam notification 2 (S208Y), there is a possibility that the separation jam is due to stuck documents, so the CPU 321 displays the document handling screen of Fig. 11 (S209) to urge the user to release the stuck documents. On the other hand, if the content of the jam notification is separation jam notification 1 or lead jam notification (S208N), there is a high possibility that the separation jam is due to a factor other than stuck documents, so the document reset screen of Fig. 12 is displayed (S210) to urge the user to reset the documents.

[0070] Thereafter, CPU 321 monitors the user's screen operations and waits for the user to reset the document and operate operation unit 90 (S211). When it detects that the user has operated operation unit 90 (S211Y), CPU 321 checks the input contents from the user (S212). If the user has pressed the "Cancel" button on the screens of Figures 11 and 12 (S212Y), CPU 321 ends the skim reading process. If the user has pressed the "OK" button (S212N), CPU 321 again notifies CPU 301 to start skim reading (S201) and continues skim reading control.

[0071] As described above, in this embodiment, when a separation jam is detected, the image reading device 1005 switches the jam release screen to notify the user based on the environmental information acquired from the environmental sensor unit 313. Specifically, when the environmental information acquired by the environmental sensor unit 313 satisfies a predetermined condition, the image reading device 1005 displays a screen prompting the user to separate the documents. On the other hand, when the environmental information acquired by the environmental sensor unit 313 does not satisfy the predetermined condition, the image reading device 1005 does not display a screen prompting the user to separate the documents. This makes it possible to prevent repeated jams by prompting the user to separate the documents when the environment in which the image reading device 1005 is installed is prone to document sticking. Furthermore, when the environment in which the image reading device 1005 is installed is not prone to document sticking, the user is not prompted to separate the documents. This prevents the user from performing unnecessary operations, improving the operability of the device.

[0072] Furthermore, in this embodiment, CPU 301 determines whether an environment is prone to original sticking based on both the temperature and humidity acquired by environmental sensor unit 313. This makes it possible to improve the accuracy of determining whether an environment is prone to original sticking. However, CPU 301 may also determine whether an environment is prone to original sticking based on only one of the temperature and humidity acquired by environmental sensor unit 313. In this case, it is only necessary to provide the device with either temperature sensor 313a or humidity sensor 313b, thereby reducing the cost of the device.

[0073] Furthermore, in this embodiment, the CPU 321 displays the document handling screen of Fig. 11 or the document reset screen of Fig. 12 after the jam release screen of Fig. 10. This allows the user to appropriately determine how to handle the document removed from the machine after a jam occurs, improving the operability of the device. In other words, it is preferable to display the document handling screen of Fig. 11 and the document reset screen of Fig. 12 after the jam release screen of Fig. 10, rather than before.

[0074] Furthermore, in this embodiment, the CPU 301 determines whether the environment in which the image reading device 1005 is installed is a condition that makes it easy for the original to stick, based on the environmental sensor unit 313 arranged in the printer 1001A. Furthermore, the printer 1001A controls the fixing temperature of the fixing unit 1029 based on the environmental information acquired by the environmental sensor unit 313. In this way, by using the environmental information acquired by the environmental sensor unit 313 to control both the printer 1001A and the image reading device 1005, it is possible to reduce the number of sensors and reduce the cost of the device. Note that the environmental sensor unit 313 may be arranged in the image reading device 1005. In this case, the CPU 321 can more accurately determine whether the environment is a condition that makes it easy for the original to stick.

[0075] The ADF 200 also includes a multi-feed sensor 221 downstream of the separation roller pair 206. When the multi-feed sensor 221 detects a multi-feed, the CPU 321 stops the separation motor 310 and the conveyance motor 311 to stop the conveyance of the original documents. When the multi-feed sensor 221 detects a multi-feed of original documents, the CPU 301 issues a separation jam notification 2 to the CPU 321, regardless of the environmental information acquired by the environmental sensor unit 313. That is, when the multi-feed sensor 221 detects a multi-feed of original documents, the image reading device 1005 displays a screen urging the user to separate the original documents, regardless of the environmental information acquired by the environmental sensor unit 313. This is because, even in an environment where conditions are not conducive to original document sticking, original documents may stick to each other depending on the type of original document. For example, original documents made of coated paper are prone to sticking to each other. Therefore, when the multi-feed sensor 221 detects a multi-feed of documents, the image reading device 1005 displays a screen prompting the user to separate the documents, thereby making it possible to prevent repeated jams from occurring.

[0076] [Second embodiment] Next, a second embodiment of the present invention will be described. In the first embodiment, a configuration has been described in which, when a separation jam is detected, the jam release screen for notifying the user is switched based on environmental information acquired from the environmental sensor unit 313. On the other hand, the second embodiment differs from the first embodiment in that, when a separation jam is detected, the jam release screen for notifying the user is switched based on the number of consecutive separation jams. Note that the basic structure of the image forming apparatus 1001 and the configuration of the controller in the second embodiment are the same as those in the first embodiment, and therefore description thereof will be omitted.

[0077] <Scanning Control> Next, the control of skimming in the second embodiment will be described. Fig. 13 is a flowchart illustrating the flow of operations of the reader controller 300 when skimming is performed. The flowchart in Fig. 13 is executed by the CPU 301 when the user issues a skimming start instruction (a reading start instruction, a copy start instruction) via the operation unit 90.

[0078] When CPU 301 receives the skim reading start command, CPU 301 performs reading preparation processing such as setting the reading resolution and color mode and shading processing (S301). When the reading preparation processing is completed, CPU 301 starts driving separation motor 310 and transport motor 311 (S302) and starts feeding the original. When separation motor 310 is driven, pickup roller 205 descends onto the top surface of the original, and feeding of the original begins.

[0079] Next, CPU 301 starts monitoring separation sensor 209 (S303). If separation sensor 209 is OFF (S303N), that is, if the document has not yet reached separation sensor 209, CPU 301 compares the separation and conveyance distance from the start of paper feed with a preset jam detection distance (S312). In S312, CPU 301 monitors whether a separation jam has occurred. If the separation and conveyance distance from the start of paper feed is longer than the jam detection distance, CPU 301 determines that a separation jam has occurred. If the separation and conveyance distance from the start of paper feed is shorter than the jam detection distance, CPU 301 again monitors whether separation sensor 209 is ON. In other words, CPU 301 repeatedly monitors separation sensor 209 until separation sensor 209 is turned ON in S303 or the separation and conveyance distance from the start of paper feed exceeds the jam detection distance in S312.

[0080] If the separation sensor 209 turns ON in S303 before the separation and conveyance distance from the start of paper feeding exceeds the jam detection distance in S312 (S303Y), the CPU 301 stops the separation motor 310 to stop paper feeding. At this time, feeding of the next document is stopped, but the conveyance motor 311 continues to convey the document that has already been separated.

[0081] Thereafter, CPU 301 begins monitoring lead sensor 212 (S305). If lead sensor 212 is OFF (S305N), i.e., if the document has not yet reached lead sensor 212, CPU 301 compares the lead transport distance since separation sensor 209 turned ON with a preset jam detection distance (S320). In S320, CPU 301 monitors whether a lead jam has occurred. If the lead transport distance since separation sensor 209 turned ON is longer than the jam detection distance, CPU 301 determines that a lead jam has occurred. If the lead transport distance since separation sensor 209 turned ON is less than the jam detection distance, CPU 301 again monitors whether lead sensor 212 is ON. In other words, CPU 301 repeatedly monitors lead sensor 212 until lead sensor 212 turns ON in S305 or the lead transport distance since separation sensor 209 turned ON in S320 exceeds the jam detection distance. The jam detection distance in S320 is different from the jam detection distance in S312.

[0082] If the lead sensor 212 turns ON in S305 before the lead transport distance after the separation sensor 209 turns ON in S320 exceeds the jam detection distance (S305Y), the CPU 301 starts the document reading process and transfer process (S306). In S306, the CPU 301 reads images on both sides of the document using the front side reading unit 103 and the back side reading unit 216. Then, the CPU 301 transfers the read image data from the image processing unit 305 to the image processing unit 324.

[0083] Thereafter, CPU 301 checks the reading status from image processing unit 305 and waits for a notification that reading has finished (S307). After reading has finished (S307Y), CPU 301 checks document detection sensor 204 (S308). If there is a next document (S308N), CPU 301 drives separation motor 310 again (S302) and starts feeding the next document. If there is no next document (S308Y), CPU 301 drives conveyance motor 311 a predetermined distance as a paper discharge process and then stops it (S309), and then notifies CPU 321 that reading has finished (S310). Furthermore, CPU 301 initializes the number of consecutive separation jams (described later) (S311). Thereafter, CPU 301 ends the skimming process.

[0084] The above-described processing from S302 to S311 is processing when no jam has occurred. Next, processing when a jam has occurred will be described. If the separation and conveyance distance from the start of paper feed exceeds the jam detection distance in S312, CPU 301 determines that a separation jam has occurred and stops separation motor 310 and conveyance motor 311 to stop the conveyance of the original. That is, if separation sensor 209 does not detect an original until a predetermined time has elapsed since the start of paper feed, CPU 301 determines that a separation jam has occurred and stops the feeding of the original.

[0085] Next, CPU 301 checks the number of consecutive separation jams (S314). The number of consecutive separation jams is the number of consecutive jams that have occurred in the separation section of ADF 200, and is stored in RAM 303. The number of consecutive separation jams is 0 when CPU 301 is started up. Initializing the number of consecutive separation jams means overwriting the number of consecutive separation jams stored in RAM 303 with 0. If the number of consecutive separation jams is equal to or greater than a predetermined threshold in S314 (S314Y), CPU 301 sends separation jam notification 2 to CPU 321 (S315). On the other hand, if the number of consecutive separation jams is less than the predetermined threshold in S314 (S314N), CPU 301 sends separation jam notification 1 to CPU 321 (S316). After sending separation jam notification 1, CPU 301 counts up the number of consecutive separation jams (S317).

[0086] Here, similar to the first embodiment, both separation jam notification 1 and separation jam notification 2 are information notifying that a jam has occurred in the separation unit, but they are different notifications. Separation jam notification 2 is a notification when it is highly likely that the jam has occurred due to documents sticking together, and separation jam notification 1 is a notification when it is highly likely that the jam has occurred due to a cause other than documents sticking together.

[0087] In this embodiment, the threshold value for the number of consecutive separation jams for issuing separation jam notification 2 is 2. That is, when a separation jam occurs two consecutive times, CPU 301 issues separation jam notification 2 to CPU 321. However, the threshold value for the number of consecutive separation jams may be set to any number equal to or greater than 2.

[0088] After the separation jam notification in S315 or S316, CPU 301 checks the status of separation sensor 209 and lead sensor 212, monitors whether any documents remain in the conveyance path, and waits for all sensors to turn OFF (S318). If all documents have been removed by the user and both separation sensor 209 and lead sensor 212 have turned OFF (S318Y), CPU 301 notifies CPU 321 of jam release (S319) and ends skimming control.

[0089] Furthermore, if the read transport distance after separation sensor 209 turns ON in S320 exceeds the jam detection distance, CPU 301 determines that a read jam has occurred and stops transport motor 311 to stop transport of the document. CPU 301 then sends a read jam notification to CPU 321 (S322). Here, the read jam notification is information notifying that a jam has occurred downstream of the separation unit. After the read jam notification, CPU 301 initializes the number of consecutive separation jams (S323). Thereafter, the process proceeds to S318 described above, and once the jam is cleared, skimming control ends.

[0090] <UI control when jam occurs> The flow of operations of the system controller 320 when a jam occurs is the same as that described in Fig. 7. That is, when the CPU 321 of the system controller 320 receives separation jam notification 2 from CPU 301, there is a possibility that the separation jam is due to a stuck document, so the CPU 321 displays the document handling screen of Fig. 11 (S209). On the other hand, when the CPU 321 receives separation jam notification 1 or lead jam notification from CPU 301, there is a high possibility that the separation jam is due to a factor other than a stuck document, so the CPU 321 displays the document reset screen of Fig. 12 (S210).

[0091] As described above, in this embodiment, the image reading device 1005 switches the jam release screen that notifies the user based on the number of times that a jam has occurred consecutively in the separation unit. Specifically, the image reading device 1005 displays a screen that prompts the user to sort the documents when a separation jam has occurred consecutively a number of times equal to or greater than a predetermined threshold. On the other hand, the image reading device 1005 does not display a screen that prompts the user to sort the documents when the number of consecutive separation jams is less than the threshold. This makes it possible to prevent repeated jams from occurring beyond the threshold.

[0092] Furthermore, when the multi-feed sensor 221 detects a multi-feed of documents, the CPU 301 notifies the CPU 321 of separation jam notification 2 regardless of the number of consecutive separation jams. That is, when the multi-feed sensor 221 detects a multi-feed of documents, the image reading device 1005 displays a screen urging the user to separate the documents regardless of the number of consecutive separation jams. This makes it possible to prevent repeated jams even for types of documents that are prone to sticking together. [Explanation of symbols]

[0093] 90 Operation section 100 Scanner unit 200 ADF 201 Document tray 205 Pickup roller 206 Separation roller pair 209 Separate Sensor 301 CPU 1001 Image forming device 1005 Image reading device

Claims

1. a document tray on which documents are loaded; a separation and feeding unit that forms a separation nip that separates the documents loaded on the document tray one by one and feeds the documents separated by the separation nip in a feeding direction; a detection sensor that detects the document downstream of the separation nip in the feeding direction; a control unit that stops feeding of the document by the separation feeding unit when the detection sensor does not detect the document until a predetermined time has elapsed since feeding of the document by the separation feeding unit has started; an environment acquisition unit that acquires environmental information including at least one of temperature and humidity; a display unit that displays information to a user; Equipped with When the control unit stops feeding of the originals based on the detection sensor, if the environmental information acquired by the environmental acquisition unit satisfies a predetermined condition, the display unit displays a predetermined screen prompting the user to sort the stack of originals, and if the environmental information acquired by the environmental acquisition unit does not satisfy the predetermined condition, the display unit does not display the predetermined screen. A document transport device characterized by:

2. The environment acquisition unit detects a temperature, the predetermined condition is that the temperature detected by the environment acquisition unit is lower than a first temperature; 2. The document transport device according to claim 1.

3. The environment acquisition unit detects a temperature, the predetermined condition is that the temperature detected by the environment acquisition unit is higher than a second temperature; 2. The document transport device according to claim 1.

4. The environment acquisition unit detects a temperature, the predetermined condition is that the temperature detected by the environment acquisition unit is lower than a first temperature, and that the temperature detected by the environment acquisition unit is higher than a second temperature that is higher than the first temperature; 2. The document transport device according to claim 1.

5. The environment acquisition unit detects humidity, the predetermined condition is that the humidity detected by the environment acquisition unit is lower than a first humidity.

2. The document transport device according to claim 1.

6. The environment acquisition unit detects humidity, the predetermined condition is that the humidity detected by the environment acquisition unit is higher than a second humidity.

2. The document transport device according to claim 1.

7. The environment acquisition unit detects humidity, the predetermined condition is that the humidity detected by the environment acquisition unit is lower than a first humidity, and that the humidity detected by the environment acquisition unit is higher than a second humidity that is higher than the first humidity; 2. The document transport device according to claim 1.

8. The environment acquisition unit detects temperature and humidity, the predetermined condition is that the temperature detected by the environment acquisition unit is lower than a first temperature and the humidity detected by the environment acquisition unit is lower than a first humidity; 2. The document transport device according to claim 1.

9. The environment acquisition unit detects temperature and humidity, the predetermined condition is that the temperature detected by the environment acquisition unit is higher than a second temperature and the humidity detected by the environment acquisition unit is higher than a second humidity; 2. The document transport device according to claim 1.

10. The environment acquisition unit detects temperature and humidity, The predetermined condition is: The predetermined condition is that the temperature detected by the environment acquisition unit is lower than a first temperature and the humidity detected by the environment acquisition unit is lower than a first humidity; and a case where the temperature detected by the environment acquisition unit is higher than a second temperature that is higher than the first temperature, and a case where the humidity detected by the environment acquisition unit is higher than a second humidity that is higher than the first humidity; 2. The document transport device according to claim 1.

11. the display unit displays the predetermined screen prompting the user to sort the stack of documents after displaying the screen prompting the user to remove the documents from the machine.

2. The document transport device according to claim 1.

12. a double feed sensor disposed downstream of the detection sensor in the feeding direction and configured to detect double feeding of the documents fed by the separation feeding unit; When the multi-feed sensor detects a multi-feed of documents, the display unit displays the predetermined screen that prompts the user to sort the document stack regardless of the environmental information acquired by the environmental acquisition unit.

2. The document transport device according to claim 1.

13. a document transport device according to any one of claims 1 to 12; a reading unit that reads an image of the document transported by the document transport device, An image reading device characterized by:

14. The image reading device according to claim 13; an apparatus main body having an image forming unit that forms an image on a recording medium based on an image of a document read by the image reading device, An image forming apparatus characterized by:

15. the environment acquisition unit is disposed in the device body, the image forming unit controls image forming conditions when forming an image on a recording medium based on the environmental information acquired by the environmental acquisition unit.

15. The image forming apparatus according to claim 14.

16. a document tray on which documents are loaded; a separation and feeding unit that forms a separation nip that separates the documents loaded on the document tray one by one and feeds the documents separated by the separation nip in a feeding direction; a detection sensor that detects the document downstream of the separation nip in the feeding direction; a control unit that stops feeding of the document by the separation feeding unit when the detection sensor does not detect the document until a predetermined time has elapsed since feeding of the document by the separation feeding unit has started; a display unit that displays information to a user; Equipped with the display unit displays a predetermined screen prompting a user to sort the stack of documents when the document feeding based on the detection sensor is stopped a threshold number of times in succession. A document transport device characterized by:

Images