JP2024057489A - Image reading device and image forming device - Google Patents

Abstract

[Problem] When a situation may occur where a small-sized document cannot be confirmed on the discharge tray, it is possible to notify the user of the situation. [Solution] In an image reading device (10), when a command is given to transport and read again on a linear transport path (46) by operating an operation unit (23), a control unit (29) determines whether a first document on a first discharge tray (40) has been detected by a document sensor (68), and if it is determined that the first document has been detected, determines whether the size of a second document on a document tray (33) detected by a size detection unit is larger than the size of the first document stored in a memory unit (27), and if it is determined that the size of the second document is larger than the size of the first document, causes a display unit (24) to display that a first document is present on the first discharge tray (40). [Selected Figure] Fig. 6

Description

The present invention relates to an image reading device that reads an image of a document while transporting the document through a curved or straight transport path, and an image forming apparatus equipped with the same.

Image reading devices read images of documents placed on a platen glass, or images of documents pulled out from a document tray and transported. Some image reading devices are also configured to pull documents out of a document tray, transport them through a transport path, and discharge them into their respective output trays, and read images of documents transported through the transport path.

In addition, in the automatic document feeder described in Patent Document 1, documents are transported from a document placement platform and discharged onto a discharge tray, and a sheet detection sensor is provided to detect the stack of documents on the discharge tray. When the sheet detection sensor detects a previously discharged stack of documents on the discharge tray, a partition lever is lowered onto the previous stack of documents to prevent the next stack of documents discharged onto the discharge tray from being mixed with the previously discharged stack of documents. In addition, when the partition lever has already been lowered and the sheet detection sensor detects a stack of documents on the discharge tray, a warning is displayed on the display unit to encourage the user to remove the stack of documents on the discharge tray.

Japanese Patent Application Laid-Open No. 08-290858

When scanning documents that are difficult to bend, such as cards, postcards, and photographs, or documents of small size, not only small documents are placed on the document tray, but large documents may also be placed on the document tray. When small and large documents are pulled out of the document tray, transported through the transport path, and discharged to the discharge tray, the small documents may become hidden under the large documents on the discharge tray and become invisible. Also, when a small document is stacked on top of a large document and another large document is stacked on top of it, the small document becomes sandwiched between the large documents, making it impossible to tell where it is. This can lead to a situation where the small document is removed together with the large document, and the small document is not returned to its owner.

In Patent Document 1, a partition lever is used to prevent the next stack of documents from being mixed with the previously discharged stack on the paper output tray, but this cannot prevent small documents from being hidden under larger documents and becoming invisible. In addition, the presence of small documents is not notified.

The present invention has been made in consideration of the above circumstances, and aims to make it possible to notify the user of situations that may occur when a small-sized document is hidden under a larger-sized document on the paper output tray, or when a small-sized document is sandwiched between two larger-sized documents, making it impossible for the user to see the small-sized document.

An image reading device according to one aspect of the present invention includes an original tray on which an original is placed, an original transport unit that pulls out the original from the original tray and transports it through a transport path, a reading unit that reads an image of the original being transported through the transport path, a size detection unit that detects the size of the original placed on the original tray, a paper output tray that receives the original discharged from an outlet of the transport path, an original detection unit that detects the original on the paper output tray, an operation unit into which a user inputs an instruction to read the original on the original tray, a display unit, a memory unit, and when an instruction to read a first original on the original tray is given by the operation unit, the size of the first original on the original tray detected by the size detection unit is stored in the memory unit, and the size of the first original on the original tray detected by the size detection unit is read by the first original. and a control unit that causes the document tray to be transported through the transport path to the first discharge tray, causes the reading unit to read an image of the first document, and when an instruction to read a second document on the document tray is input by operating the operation unit, determines whether the first document on the discharge tray is detected by the document detection unit, and when it is determined that the first document on the discharge tray is detected, determines whether the size of the second document on the document tray detected by the size detection unit is larger than the size of the first document stored in the memory unit, and when it is determined that the size of the second document is larger than the size of the first document, causes the display unit to display that the first document is on the discharge tray.

In addition, an image reading device according to one aspect of the present invention includes an original tray on which an original is placed, an original transport unit that pulls out the original from the original tray and transports it through a transport path, a reading unit that reads an image of the original being transported through the transport path, a size detection unit that detects the size of the original on the original tray and the size of the original being transported through the transport path, a paper discharge tray that receives the original discharged from an outlet of the transport path, an original detection unit that detects the original on the paper discharge tray, an operation unit to which a user inputs an instruction to read the original on the original tray, a display unit, a memory unit, and when an instruction to read a first original on the original tray is given by the operation unit, the size of the first original on the original tray detected by the size detection unit is stored in the memory unit, the first original is transported from the original tray to the first paper discharge tray through the transport path, and the image of the first original is read by the reading unit, and the original tray is read by the operation of the operation unit. and a control unit that, when an instruction to read a second document on the tray is input, determines whether the first document on the first discharge tray is detected by the document detection unit, and when it is determined that the first document on the first discharge tray is detected, determines whether the size of the second document on the document tray detected by the size detection unit is equal to or smaller than the size of the first document stored in the memory unit, and when it is determined that the size of the second document is equal to or smaller than the size of the first document, sequentially conveys a plurality of second documents from the document tray to the first discharge tray through the conveying path, sequentially reads the image of each second document by the reading unit, detects the size of each second document conveyed through the conveying path by the size detection unit, and, when the size of any second document is smaller than the size of another second document following the page of the second document, causes the display unit to display that a small-sized second document is mixed in with each second document on the first discharge tray.

In addition, an image reading device according to one aspect of the present invention includes an original tray on which an original is placed, an original transport unit that pulls out the original from the original tray and transports the original through either a straight transport path or a curved transport path, a first reading unit that reads an image of the original being transported through the straight transport path, a second reading unit that reads an image of the original being transported through the curved transport path, a size detection unit that detects the size of the original placed on the original tray, a first paper discharge tray that receives the original discharged from an outlet of the straight transport path, a second paper discharge tray that receives the original discharged from an outlet of the curved transport path, an original detection unit that detects the original on the first paper discharge tray, an operation unit into which a user inputs an instruction as to whether the original is to be transported through the straight transport path or the curved transport path, a display unit, a memory unit, and a control unit that controls the operation unit to input .... When the transport path is instructed, the size of the first document on the document tray detected by the size detection unit is stored in the memory unit, the first document is transported from the document tray to the first discharge tray through the linear transport path, and the image of the first document is read by the first reading unit. When the linear transport path is instructed again by operating the operation unit, the document detection unit determines whether the first document on the first discharge tray has been detected, and if it is determined that the first document on the first discharge tray has been detected, it determines whether the size of the second document on the document tray detected by the size detection unit is larger than the size of the first document stored in the memory unit, and if it is determined that the size of the second document is larger than the size of the first document, it causes the display unit to display that the first document is on the first discharge tray.

An image forming apparatus according to one aspect of the present invention includes the image reading device of the present invention described above, and an image forming section that forms an image of the document read by the image reading device on recording paper.

According to the present invention, when a small-sized document is hidden under a larger-sized document on the output tray, or when a small-sized document is sandwiched between larger-sized documents on the output tray, making it impossible for the user to see the small-sized document, it is possible to notify the user of this situation.

1 is a cross-sectional view showing an image forming apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing an image reading device in the image forming apparatus. FIG. 1 is a perspective view showing an external appearance of an image reading device. 2 is an enlarged view showing a path along which a document is transported in the image reading device according to the embodiment; FIG. 11 is an enlarged view showing another path along which a document is transported in the image reading device of the present embodiment. FIG. 1 is a block diagram showing a main internal configuration of an image forming apparatus; 11 is a flowchart showing a control procedure for determining the occurrence of an event in which a small-sized document cannot be confirmed on the first discharge tray and notifying the user of the occurrence. 7B is a flowchart showing a control procedure subsequent to FIG. 7A. 7C is a flowchart showing a control procedure subsequent to FIG. 7B. FIG. 13 is a diagram showing a warning message displayed on a display unit. FIG. 13 is a diagram showing another warning message displayed on the display unit.

The image reading device and image forming device according to the embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an image forming device according to one embodiment of the present invention. As shown in FIG. 1, the image forming device 10 of this embodiment includes an image reading device 20 and an image forming unit 21.

The image reading device 20 has an image sensor (e.g., a CCD) that optically reads the image of the document, and the analog output of this image sensor is converted into a digital signal to generate image data representing the image of the document.

The image forming unit 21 prints an image represented by the image data on a recording sheet, and includes an image forming unit 3M for magenta, an image forming unit 3C for cyan, an image forming unit 3Y for yellow, and an image forming unit 3Bk for black. In each of the image forming units 3M, 3C, 3Y, and 3Bk, the surface of the photosensitive drum 4 is uniformly charged, the surface of the photosensitive drum 4 is exposed to light, an electrostatic latent image is formed on the surface of the photosensitive drum 4, the electrostatic latent image on the surface of the photosensitive drum 4 is developed into a toner image, and the toner image on the surface of the photosensitive drum 4 is transferred to the intermediate transfer belt 5. As a result, a color toner image is formed on the intermediate transfer belt 5. This color toner image is secondarily transferred to the recording sheet P transported from the paper feed unit 14 through the first transport path 8 in the nip area N between the intermediate transfer belt 5 and the secondary transfer roller 6.

After this, the recording paper P is heated and pressurized by the fixing device 15 to fix the toner image on the recording paper P by thermocompression, and the recording paper P is then discharged to the paper discharge tray 17 via the discharge rollers 16.

When an image of the original M is to be recorded on the reverse side of the recording paper P, the recording paper P is transported to the discharge rollers 16 in front of the paper discharge tray 17, the discharge rollers 16 are stopped once and then rotated in the reverse direction (switchback transport), the recording paper P is returned from the transport rollers 18 to the first transport path 8 via the second transport path 9, the recording paper P is turned over, the image forming unit 21 forms an image of the original M on the reverse side of the recording paper P, and the recording paper P is discharged to the paper discharge tray 17 via the discharge rollers 16.

Next, the image reading device 20 will be described. FIG. 2 is a cross-sectional view showing the image reading device 20. FIG. 3 is a perspective view showing the exterior of the image reading device 20, showing the document transport unit 31 in an open state.

As shown in Figures 2 and 3, the image reading device 20 includes a document transport unit 31 and a document reading unit 32. The document transport unit 31 includes a document tray 33, a paper feed roller 34, a transport belt 35, a retard roller 36, a registration roller 37, a plurality of transport rollers 38A, 38B, a first discharge roller 39, a first discharge tray 40, a contact image sensor 41, a contact image sensor 43, a second discharge roller 48, and a second discharge tray 49.

The contact image sensor 41 corresponds to the first reading unit in the claims, and hereinafter the contact image sensor 41 will be referred to as the first reading unit 41. Also, hereinafter the contact image sensor 43 will be referred to as the third reading unit 43.

In the document transport section 31, when the document M is placed on the document tray 33, the document M is pulled out of the document tray 33 by the paper feed roller 34, and the document M is guided and transported to the common transport path 45 through the transport belt 35 and the retard roller 36, and the document M is further transported through the straight transport path 46, or through the curved transport path 47.

A switching claw 44 is provided at the branching position of the straight transport path 46 and the curved transport path 47. The shaft at the left end of the switching claw 44 is rotated back and forth within a certain rotation range by an actuator (not shown), so that the tip of the switching claw 44 is directed diagonally upward or horizontally. When the tip of the switching claw 44 is directed horizontally, the document M is guided and transported from the common transport path 45 to the straight transport path 46, and when the tip of the switching claw 44 is directed diagonally upward, the document M is guided and transported from the common transport path 45 to the curved transport path 47.

In the common transport path 45, the document M is transported from the registration roller 37 through between the third reading section 43 and the shading roller 42 to the switching claw 44.

In the linear transport path 46, the document M is guided horizontally by the switching claw 44 and transported between the first reading section 41 and the shading roller 42, and the document M is discharged to the first discharge tray 40 by the first discharge roller 39.

In the curved transport path 47, the original M is guided downward by the switching claw 44 and transported to the first platen glass 51, where the original M passes over the first platen glass 51 and is discharged to the second discharge tray 49 by the second discharge roller 48.

The document tray 33 is also provided with a length sensor 61 that detects the length of the document M placed on the document tray 33, and a width sensor 62 that detects the width of the document M. The length sensor 61 is, for example, a plurality of optical sensors that are arranged at intervals in the length direction of the document M and embedded in the document tray 33. Each optical sensor is composed of a light-emitting element and a light-receiving element, and when light emitted from the light-emitting element of the optical sensor is reflected by the document M on the document tray 33, the reflected light is received by the light-receiving element of the optical sensor, causing the output of the light-receiving element to change. The length of the document M is determined based on the position of the light-receiving element of at least one optical sensor that receives the reflected light.

Similarly, the width sensor 62 is, for example, a number of optical sensors that are arranged at intervals in the width direction of the document M and embedded in the document tray 33. When light emitted from the light-emitting element of each optical sensor is reflected by the document M, the reflected light is received by the light-receiving element of the optical sensor, causing the output of the light-receiving element to change. The width of the document M is determined based on the position of the light-receiving element of at least one optical sensor that receives the reflected light.

The first discharge tray 40 is also provided with a discharge sensor 67 that detects the document M discharged to the first discharge tray 40. The discharge sensor 67 is, for example, an optical sensor consisting of a light-emitting element and a light-receiving element. When light emitted from the light-emitting element is reflected by the document M on the first discharge tray 40, the reflected light is received by the light-receiving element, and the document M is detected based on the output of the light-receiving element.

The document tray 33 is also provided with a document sensor 68 that detects the document M placed on the document tray 33. The document sensor 68 is, for example, an optical sensor consisting of a light-emitting element and a light-receiving element. When light emitted from the light-emitting element is reflected by the document M on the document tray 33, the reflected light is received by the light-receiving element, and the document M is detected based on the output of the light-receiving element.

On the other hand, as shown in Figures 2 and 3, the document reading unit 32 includes a first platen glass 51, a second platen glass 52, a carriage 54, an optical system unit 55, a condenser lens 56, and a CCD sensor 12.

The CCD sensor 12 corresponds to the second reading unit in the claims, and hereafter, the CCD sensor 12 will be referred to as the second reading unit 12.

In the document reading section 32, the carriage 54 includes a light source 54A that irradiates light onto the document, and a mirror 54B that reflects the light reflected by the document M. The optical system unit 55 also includes a mirror 55A and a mirror 55B. The mirror 55A receives the light reflected by the mirror 54B of the carriage 54 and redirects it approximately vertically downward. The mirror 55B redirects the light reflected by the mirror 55A approximately horizontally and guides it to the second reading section 12 via the focusing lens 56.

The carriage 54 and optical system unit 55 are arranged to be movable back and forth along rails in a sub-scanning direction X perpendicular to the main scanning direction Y, and are moved in the sub-scanning direction X while maintaining a predetermined speed relationship by a known drive mechanism powered by a stepping motor (not shown).

Two hinges 58 are provided at a distance from one another at one end of the upper surface 32a of the document reading unit 32, and these hinges 58 support the document transport unit 31 so that it can be opened and closed, allowing the user to open and close the document transport unit 31.

Here, the image reading device 20 has five types of operation modes for reading the image of the original M: a stationary original reading mode, a first transported original single-sided reading mode, a second transported original single-sided reading mode, a first transported original double-sided reading mode, and a second transported original double-sided reading mode. One of these modes is selected by the user, and the image of the original M is read in the selected mode.

The stationary document reading mode is an operation for reading an image on the downward facing surface of the document M placed on the second platen glass 52, and the second reading section 12 of the document reading unit 32 reads the image on the surface of the document M through the second platen glass 52.

When the stationary document reading mode is selected, the document transport unit 31 is opened, and the document M is placed on the second platen glass 52 with its surface facing down while the second platen glass 52 of the document reading unit 32 is open. The document transport unit 31 is closed, and the document M placed on the second platen glass 52 is pressed down by the document transport unit 31. In the document reading unit 32, the carriage 54 and the optical system unit 55 are moved in the sub-scanning direction X while maintaining a predetermined speed relationship, and the light of the light source 54A of the carriage 54 is irradiated onto the surface of the document M through the second platen glass 52, and the light reflected by the surface of the document M is reflected by the mirror 54B of the carriage 54. Furthermore, this light is reflected by the mirrors 55A and 55B of the optical system unit 55 and enters the second reading unit 12 through the condenser lens 56. The second reading unit 12 repeatedly reads the image on the surface of the document M in the main scanning direction Y (direction perpendicular to the sub-scanning direction X).

The first transported original single-sided reading mode is an operation for reading the image on the upward facing surface of the original M placed on the original tray 33 while transporting the original M. The original M is transported from the original tray 33 to the common transport path 45 to the straight transport path 46 to the first discharge tray 40, and the first reading unit 41 reads the image on the upward facing surface of the original M.

When the first transported document one-sided reading mode is selected, as shown in FIG. 4, the document transport section 31 is closed and the document M is placed on the document tray 33 with its surface facing up. The document M is pulled out of the document tray 33 by the paper feed roller 34 and transported through the common transport path 45. The document M is guided by the switching claw 44 from the common transport path 45 to the linear transport path 46 and transported. The document M passes between the first reading section 41 and the shading roller 42, and is discharged to the first discharge tray 40. The first reading section 41 repeatedly reads the image of the upward facing surface of the document M passing between the first reading section 41 and the shading roller 42 in the main scanning direction Y.

The second transported original single-sided reading mode is an operation for reading the image of the upward facing surface of the original M placed on the original tray 33 while transporting the original M. The original M is transported from the original tray 33 to the common transport path 45 to the curved transport path 47 to the second discharge tray 49, and the second reading section 12 of the original reading section 32 reads the image of the surface of the original M through the first platen glass 51.

When the second transported original single-sided reading mode is selected, with the original transport section 31 closed as shown in FIG. 5, the original M is placed with its front side facing up on the original tray 33, the original M is pulled out of the original tray 33 by the paper feed roller 34, the original M is transported through the common transport path 45, the original M is guided by the switching claw 44 from the common transport path 45 to the curved transport path 47 and transported, and the original M passes over the first platen glass 51 and is discharged to the second discharge tray 49. In the document reading section 32, the carriage 54 and the optical system unit 55 are positioned at their respective predetermined positions below the first platen glass 51, and the light from the light source 54A of the carriage 54 is irradiated onto the surface of the document M through the first platen glass 51. The light reflected from the surface of the document M is reflected by each mirror 54B, 55A, 55B and made to enter the second reading section 12 through the condenser lens 56, and the image on the surface of the document M is repeatedly read by the second reading section 12 in the main scanning direction Y.

The first transported document double-sided reading mode is an operation for reading images on both sides of a document M placed on the document tray 33 while the document M is being transported. The document M is transported from the document tray 33 to the common transport path 45 to the straight transport path 46 to the first discharge tray 40. The third reading unit 43 reads an image on the downward facing back side of the document M being transported through the common transport path 45, and the first reading unit 41 reads an image on the upward facing front side of the document M being transported through the straight transport path 46.

When the first transport document double-sided reading mode is selected, as shown in FIG. 4, the document transport section 31 is closed, and the document M is placed on the document tray 33 with its front side facing up. The document M is pulled out from the document tray 33 by the paper feed roller 34, and the document M is transported through the common transport path 45, passes between the third reading section 43 and the shading roller 42, and is guided by the switching claw 44 from the common transport path 45 to the straight transport path 46 and transported, passes between the first reading section 41 and the shading roller 42, and is discharged to the first discharge tray 40. The third reading section 43 repeatedly reads the image of the downward-facing back side of the document M passing between the third reading section 43 and the shading roller 42 in the main scanning direction Y. The first reading section 41 repeatedly reads the image of the upward-facing front side of the document M passing between the first reading section 41 and the shading roller 42 in the main scanning direction Y.

The second transported document double-sided reading mode is an operation for reading images on both sides of a document M placed on the document tray 33 while the document M is being transported. The document M is transported from the document tray 33 to the common transport path 45 to the curved transport path 47 to the second discharge tray 49. The third reading unit 43 reads the image on the downward facing back side of the document M being transported through the common transport path 45, and the second reading unit 12 of the document reading unit 32 reads the image on the front side of the document M through the first platen glass 51.

When the second transport document double-sided reading mode is selected, as shown in FIG. 5, the document transport section 31 is closed, and the document M is placed on the document tray 33 with its front side facing up. The document M is pulled out of the document tray 33 by the paper feed roller 34 and transported through the common transport path 45. The document M passes between the third reading section 43 and the shading roller 42. The document M is guided by the switching claw 44 from the common transport path 45 to the curved transport path 47 and transported. The document M passes over the first platen glass 51 and is discharged to the second discharge tray 49. The third reading section 43 reads the image of the downward facing back side of the document M passing between the third reading section 41 and the shading roller 42. In addition, in the document reading unit 32, light from the light source 54A of the carriage 54 is irradiated onto the surface of the document M through the first platen glass 51, and the light reflected from the surface of the document M is reflected by each mirror 54B, 55A, 55B and made to enter the second reading unit 12 through the condenser lens 56, causing the second reading unit 12 to repeatedly read the image on the surface of the document M in the main scanning direction Y.

Figure 6 is a block diagram showing the internal configuration of the image forming device 10. As shown in Figure 6, the image forming device 10 includes an image reading device 20, an image forming unit 21, an operation unit 23, a display unit 24, a touch panel 25, an image memory 26, a storage unit 27, and a control unit 28. These components are capable of transmitting and receiving data or signals to and from each other via a bus.

The operation unit 23 has physical keys such as a numeric keypad and a confirmation key. The display unit 24 is composed of a liquid crystal display (LCD) or an organic light-emitting diode (OLED) display.

A touch panel 25 is disposed on the screen of the display unit 24. The touch panel 25 is a so-called resistive film type or capacitive type touch panel, which detects contact (touch) of a user's finger or the like with the touch panel 25 together with the contact position, and outputs a detection signal indicating the coordinates of the contact position to a control unit 29 of the control unit 28, which will be described later.

The image memory 26 temporarily stores image data representing the image of the document read by the image reading device 20.

The storage unit 27 is a large-capacity storage device such as an SSD (Solid State Drive) or HDD (Hard Disk Drive), and stores various application programs and various data.

The control unit 28 is composed of a processor, a RAM (Random Access Memory), a ROM (Read Only Memory), etc. The processor is, for example, a CPU (Central Processing Unit), an ASIC (Application Specific Integrated Circuit), or an MPU (Micro Processing Unit). The control unit 28 functions as a control unit 29 by the processor executing a control program stored in the ROM or the memory unit 27.

The control unit 29 controls the image forming device 10. The control unit 28 is connected to the image reading device 20, the image forming unit 21, the operation unit 23, the display unit 24, the touch panel 25, the image memory 26, and the storage unit 27. The control unit 29 controls the operation of these components and transmits and receives signals and data between these components.

The control unit 29 serves as a processing unit that executes various processes required for image formation by the image forming device 10. The control unit 29 also accepts operation instructions input by the user based on a detection signal output from the touch panel 25 or the operation of a physical key on the operation unit 23. For example, the control unit 29 accepts touch operations on a GUI (Graphical User Interface) displayed on the screen of the display unit 24 through the touch panel 25. Furthermore, the control unit 29 has a function of controlling the display operation of the display unit 24.

As described above, the document tray 33 of the image reading device 20 is provided with a length sensor 61 that detects the length of the document M, and a width sensor 62 that detects the width of the document M. The control unit 29 determines the length of the document M based on the detection output of the length sensor 61, and determines the width of the document M based on the detection output of the width sensor 62.

As described above, the first discharge tray 40 of the image reading device 20 is provided with a discharge sensor 67 that detects the document M. The control unit 29 determines whether or not the document M has been discharged to the first discharge tray 40 based on the detection output of the discharge sensor 67.

As described above, the document tray 33 of the image reading device 20 is provided with a document sensor 68 that detects the document M. The control unit 29 determines whether or not the document M is placed on the document tray 33 based on the detection output of the document sensor 68.

The control unit 29 also determines the width of the document M based on the output of the third reading unit 43 (contact image sensor) when the document M passes between the third reading unit 43 and the shading roller 42.

The control unit 29 also controls the motors, actuators, clutches, etc. for operating the paper feed roller 34, the conveying belt 35, the resist roller 37, the shading rollers 42, the conveying rollers 38A, 38B, the first discharge roller 39, the second discharge roller 48, and the switching claw 44 in the document conveying unit 31 of the image reading device 20, and operates these to pull out the document M from the document tray 33 and convey it through the common conveying path 45, the straight conveying path 46, or the curved conveying path 47.

The control unit 29 also controls the reading operation of the original document M by the first reading unit 41, the third reading unit 43, and the second reading unit 12.

In the image forming device 10 configured as described above, for example, a user operates the GUI displayed on the display unit 24 to input a selection instruction to select the stationary document reading mode via the operation unit 23, places the document M with its surface facing down on the second platen glass 52 of the document reading unit 32, and operates the start key of the operation unit 23 to input a reading instruction. The control unit 29 sets the stationary document reading mode and controls the document reading unit 32 in response to the reading instruction, causing the second reading unit 12 of the document reading unit 32 to read the image of the surface of the document M on the second platen glass 52 as described above, stores image data representing the image of the surface of the document M in the image memory 26, and causes the image forming unit 21 to form the image of the surface of the document M represented by this image data on the recording paper P.

The user also operates the GUI displayed on the display unit 24 to select the first transported original one-sided reading mode, places the original M on the original tray 33 with its surface facing up, and operates the start key on the operation unit 23. The control unit 29 sets the first transported original one-sided reading mode in accordance with the selection instruction, controls the original transport unit 31 to transport the original M along the path of the original tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40 (see FIG. 4), causes the first reading unit 41 to read the image of the upward facing surface of the original M, stores image data representing the image of the surface of the original M in the image memory 26, and causes the image forming unit 21 to form the image of the surface of the original M represented by the image data on a recording sheet.

The user also operates the GUI displayed on the display unit 24 to select the second transport document one-sided reading mode, places the document M on the document tray 33 with its surface facing up, and operates the start key on the operation unit 23. The control unit 29 sets the second transport document one-sided reading mode according to the selection instruction, controls the document transport unit 31 to transport the document M through the document tray 33 → common transport path 45 → curved transport path 47 → second discharge tray 49 (see FIG. 4), causes the second reading unit 12 to read the image of the surface of the document M through the first platen glass 51, stores image data representing the image of the surface of the document M in the image memory 26, and causes the image forming unit 21 to form the image of the surface of the document M represented by the image data on a recording sheet.

The user also operates the GUI displayed on the display unit 24 to select the first transported document double-sided reading mode, places the document M on the document tray 33 with its front side facing up, and operates the start key on the operation unit 23. The control unit 29 sets the first transported document double-sided reading mode according to the selection instruction, controls the document transport unit 31 to transport the document M along the path of the document tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40 (see FIG. 4), causes the third reading unit 43 to read the image of the downward facing back side of the document M, causes the first reading unit 41 to read the image of the upward facing front side of the document M, stores the image data representing the front and back sides of the document M in the image memory 26, and causes the image forming unit 21 to form the images of the front and back sides of the document M represented by these image data on the front and back sides of the recording paper.

The user also operates the GUI displayed on the display unit 24 to select the second transport document double-sided reading mode, places the document M on the document tray 33 with its front side facing up, and operates the start key on the operation unit 23. The control unit 29 sets the second transport document double-sided reading mode according to the selection instruction, controls the document transport unit 31 to transport the document M through the document tray 33 → common transport path 45 → curved transport path 47 → second discharge tray 49 (see FIG. 5), causes the third reading unit 43 to read the image of the downward facing back side of the document M, causes the second reading unit 12 to read the image of the front side of the document M through the first platen glass 51, stores the image data representing the front side image and the back side image of the document M in the image memory 26, and causes the image forming unit 21 to form the front side image and the back side image of the document M represented by these image data on the front and back sides of the recording paper.

In the image reading device 20, the straight transport path 46 is suitable for transporting documents that are difficult to bend, such as cards, postcards, and photographs, or documents of small size, while the curved transport path 47 is suitable for transporting documents made of paper that bends flexibly, or documents of large size. For this reason, when a document is difficult to bend and is small in size, it is preferable to read the document in the first transport document single-sided reading mode or the first transport document double-sided reading mode, and when a document is flexibly bent and is large in size, it is preferable to read the document in the second transport document single-sided reading mode or the second transport document double-sided reading mode.

However, in the first transported document single-sided reading mode or the first transported document double-sided reading mode, not only images of small-sized documents but also images of large-sized documents are read. In this case, small-sized documents and large-sized documents are pulled out of the document tray 33, transported through the linear transport path 46, and discharged to the first discharge tray 40, and the small-sized documents may be hidden under the large-sized documents and become invisible to the user. Also, if a small-sized document is stacked on top of a large-sized document and another large-sized document is stacked on top of it, the small-sized document will be sandwiched between the large-sized documents, making it impossible for the user to know of the existence of the small-sized document. This can result in a situation where the small-sized document is removed together with the large-sized document and not returned to its owner.

In this embodiment, the image reading device 20, when performing control that may cause a situation in which a small-sized document becomes hidden under a larger-sized document on the first discharge tray 40, or becomes sandwiched between larger-sized documents, making it impossible to view the small-sized document, notifies the user of the possibility of such an event and prevents the event from occurring.

Next, the control procedure for predicting the occurrence of such an event and notifying the user will be described with reference to the flowcharts shown in Figures 7A, 7B, and 7C.

The user operates the GUI displayed on the display unit 24 to input a selection instruction to select one of the stationary document reading mode, the first transported document single-sided reading mode, the second transported document single-sided reading mode, the first transported document double-sided reading mode, and the second transported document double-sided reading mode, and places the document M with its surface facing down on the second platen glass 52 or places the document M with its surface facing up on the document tray 33, and operates the start key on the operation unit 23 to input a reading instruction.

Based on the input selection instruction, the control unit 29 determines whether the stationary document reading mode, the first transported document single-sided reading mode, the second transported document single-sided reading mode, the first transported document double-sided reading mode, or the second transported document double-sided reading mode has been selected (S101).

For example, when the control unit 29 determines that the stationary document reading mode has been selected (S101 "Stationary"), it executes the stationary document reading mode in response to a reading instruction input by operating the start key on the operation unit 23, causes the second reading unit 12 of the document reading unit 32 to read the image of the front side of the document M on the second platen glass 52 (S102), and causes the image forming unit 21 to form the image of the front side of the document M on recording paper (S103). After this, the control procedure shown in Figures 7A to 7C ends.

When the control unit 29 determines that the second transported original single-sided reading mode or the second transported original double-sided reading mode has been selected (S101 "second"), it executes the second transported original single-sided reading mode or the second transported original double-sided reading mode in response to the operation of the start key on the operation unit 23, transports the original M along the path from the original tray 33 → common transport path 45 → curved transport path 47 → second discharge tray 49 (see Figure 5), causes the second reading unit 12 to read the image of the front side of the original M, or causes the third reading unit 43 and the second reading unit 12 to read the image of the downward-facing back side of the original M and the image of the front side of the original M (S104), and causes the image of the front side of the original M to be formed on recording paper by the image forming unit 21, or causes the image of the front side and the image of the back side of the original M to be formed on the front and back sides of the recording paper by the image forming unit 21 (S105). When the control unit 29 determines that there is an original M on the original tray 33 based on the detection output of the original sensor 68 (S106 "Yes"), it repeats S104 and S105. When the control unit 29 determines that there is no original M on the original tray 33 based on the detection output of the original sensor 68 (S106 "No"), that is, when reading of the images of all the originals M on the original tray 33 is completed, the control procedure shown in Figures 7A to 7C ends.

Therefore, the stationary document reading mode, the second transported document single-sided reading mode, or the second transported document double-sided reading mode are executed as normal.

When the control unit 29 determines that the first transported original single-sided reading mode or the first transported original double-sided reading mode has been selected (S101 "first"), it determines the length of the original M based on the detection output of the length sensor 61 provided in the original tray 33, and determines the width of the original M based on the detection output of the width sensor 62 provided in the original tray 33, thereby obtaining the size of the original M, and stores this obtained size of the original M in the memory unit 27 (S107).

Then, after the image forming device 10 is turned on and the image forming device 10 and the image reading device 20 are started, the control unit 29 determines whether the first transported original single-sided reading mode or the first transported original double-sided reading mode has been selected for the first time since startup (S108).

When the control unit 29 determines that the first transported original single-sided reading mode or the first transported original double-sided reading mode has been selected for the first time (S108 "Yes"), it determines whether or not there is an original M discharged to the first discharge tray 40 based on the detection output of the discharge sensor 67 (S109).

For example, when the control unit 29 determines that no original M has been discharged to the first discharge tray 40 (S109 "No"), it executes the first transported original single-sided reading mode or the first transported original double-sided reading mode in response to a reading instruction input by the start key of the operation unit 23, transports the original M along the path from the original tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40 (see Figure 4), causes the first reading unit 41 to read the image of the upward facing front side of the original M, or causes the third reading unit 43 and the first reading unit 41 to read the image of the downward facing back side of the original M and the image of the upward facing front side of the original M (S110), and causes the image of the front side of the original M to be formed on recording paper by the image forming unit 21, or causes the image of the front side and the image of the back side of the original M to be formed on the front and back sides of the recording paper by the image forming unit 21 (S111). When the control unit 29 determines that there is an original M on the original tray 33 based on the detection output of the original sensor 68 (S112 "Yes"), it repeats S110 and S111. When the control unit 29 determines that there is no original M on the original tray 33 based on the detection output of the original sensor 68 (S112 "No"), that is, when reading of the images of all the originals M on the original tray 33 is completed, the control procedure shown in Figures 7A to 7C ends.

Therefore, when the first transported original single-sided reading mode or the first transported original double-sided reading mode is selected for the first time and there is no original M discharged to the first discharge tray 40, the first transported original single-sided reading mode or the first transported original double-sided reading mode is executed as normal.

Furthermore, when the control unit 29 determines that there is an original document M discharged to the first discharge tray 40 (S109 "Yes"), it assumes that the original document M discharged to the first discharge tray 40 is of a preset minimum size (S113). This is because immediately after starting up the image forming device 10 and the image reading device 20, the size of the original document M remaining on the first discharge tray 40 is unknown, and so the size of the remaining original document M is assumed to be the minimum size that is likely to be hidden under another larger original document M. Here, for example, the minimum size is set to the standard size A5.

The control unit 29 determines whether the size of the document M on the document tray 33 is larger than the minimum size (S114), and if the size of the document M on the document tray 33 is equal to or smaller than the minimum size (S114 "No"), in response to the operation of the start key of the operation unit 23, executes the first transport document one-sided reading mode or the first transport document two-sided reading mode, and transports the document M along the path of the document tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40 (see FIG. 4). Then, the control unit 29 causes the first reading unit 41 to read the image of the upward facing front side of the document M, or causes the third reading unit 43 and the first reading unit 41 to read the image of the downward facing back side of the document M and the image of the upward facing front side of the document M (S110), and causes the image forming unit 21 to form the image of the front side of the document M on the recording paper, or causes the image forming unit 21 to form the image of the front side and the image of the back side of the document M on the front and back sides of the recording paper (S111). When the control unit 29 determines that the document M is present on the document tray 33 based on the detection output of the document sensor 68 (S112 "Yes"), it repeats S110 and S111, and when it determines that the document M is not present on the document tray 33 based on the detection output of the document sensor 68 (S112 "No"), the control procedure shown in Figures 7A to 7C ends.

Therefore, when the first transported document single-sided reading mode or the first transported document double-sided reading mode is selected for the first time, there is a document M discharged to the first discharge tray 40, and the size of the document M on the document tray 33 is equal to the minimum size, the first transported document single-sided reading mode or the first transported document double-sided reading mode is executed as normal. As described above, the size of the document M discharged to the first discharge tray 40 is considered to be the minimum standard size A5, so even if a document M of the standard size A5 is pulled out from the document tray 33, transported, and discharged to the first discharge tray 40, the discharged document M will not hide the document M of the standard size A5 discharged to the first discharge tray 40. Therefore, the first transported document single-sided reading mode or the first transported document double-sided reading mode is executed as normal.

When the control unit 29 determines that the size of the document M on the document tray 33 is larger than the minimum size (S114 "Yes"), it prohibits the document M from being transported via the path from the document tray 33 to the common transport path 45 to the straight transport path 46 to the first discharge tray 40, and causes the display unit 24 to display a warning message M1 urging the user to remove the document M discharged to the first discharge tray 40, and further starts timing the elapsed time T since the warning message M1 was displayed (S115).

Figure 8 shows an example of the screen of the display unit 24 on which a warning message M1 is displayed. If a large-sized original M is transported from the original tray 33 to the common transport path 45 to the straight transport path 46 to the first discharge tray 40, this large-sized original M may overlap an original M deemed to be the smallest size that has already been discharged to the first discharge tray 40, making it impossible to confirm this original M deemed to be the smallest size. For this reason, the original M is prohibited from being transported to the first discharge tray 40, and a warning message M1 is displayed on the display unit 24.

After S115, the control unit 29 determines whether the start key of the operation unit 23 has been operated (S116), and determines whether there are no documents M on the document tray 33 based on the detection output of the document sensor 68 (S117), and further determines whether the elapsed time T has reached a certain time t (S118).

Here, before the elapsed time T reaches a certain time t (S118 "No"), the control unit 29 determines that the start key of the operation unit 23 has been operated (S116 "Yes"), or determines that there is no original M on the original tray 33 based on the detection output of the original sensor 68 (S117 "Yes"), and executes the first transported original single-sided reading mode or the first transported original double-sided reading mode, transporting the original M along the path of the original tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40 (see Figure 4), and causes the first reading unit 41 to read the image of the upward facing front side of the original M, or causes the third reading unit 43 and the first reading unit 41 to read the image of the downward facing back side of the original M and the image of the upward facing front side of the original M (S110). Then, the control unit 29 causes the image forming unit 21 to form an image of the front side of the document M on the recording paper, or causes the image forming unit 21 to form an image of the front side and an image of the back side of the document M on the front and back sides of the recording paper (S111). When the control unit 29 determines that the document M is present on the document tray 33 based on the detection output of the document sensor 68 (S112 "Yes"), it repeats S110 and S111, and when it determines that the document M is not present on the document tray 33 based on the detection output of the document sensor 68 (S112 "No"), the control procedure shown in Figures 7A to 7C ends.

After the warning message M1 is displayed, if the start key on the operation unit 23 is operated to input a reading instruction, it is assumed that the user is aware that there is a document M on the first discharge tray 40, and in response to the reading instruction, the large-sized document M is pulled out of the document tray 33, transported, and discharged to the first discharge tray 40. Also, if it is determined based on the detection output of the document sensor 68 that there is no document M on the document tray 33, it is assumed that the document M on the first discharge tray 40 has been removed by the user, and the large-sized document M is pulled out of the document tray 33, transported, and discharged to the first discharge tray 40.

Furthermore, if the elapsed time T reaches a certain time t (S118 "Yes") without determining that the start key on the operation unit 23 has been operated to input a reading command (S116 "No"), or without determining that there is no original M on the original tray 33 based on the detection output of the original sensor 68 (S117 "No"), the control unit 29 executes the second transported original single-sided reading mode or the second transported original double-sided reading mode, transports the original M via the original tray 33 → common transport path 45 → curved transport path 47 → second discharge tray 49 (see Figure 5), and causes the second reading unit 12 to read the image of the front side of the original M, or causes the third reading unit 43 and the second reading unit 12 to read the image of the downward-facing back side of the original M and the image of the front side of the original M (S104). Then, the control unit 29 causes the image forming unit 21 to form an image of the front side of the document M on the recording paper, or causes the image forming unit 21 to form an image of the front side and an image of the back side of the document M on the front and back sides of the recording paper (S105). When the control unit 29 determines that the document M is present on the document tray 33 based on the detection output of the document sensor 68 (S106 "Yes"), it repeats S104 and S105, and when it determines that the document M is not present on the document tray 33 based on the detection output of the document sensor 68 (S106 "No"), it ends the control procedure shown in Figures 7A to 7C.

Therefore, when the first transported original single-sided reading mode or the first transported original double-sided reading mode is selected for the first time, there is an original M discharged to the first discharge tray 40, and the size of the original M on the original tray 33 is larger than the minimum size, a warning message M1 is displayed on the display unit 24, and when the start key is operated or the original M on the first discharge tray 40 is removed, the first transported original single-sided reading mode is executed, and the large-sized original M is pulled out from the original tray 33, transported, and discharged to the first discharge tray 40. Also, when a certain time t has elapsed since the warning message M1 was displayed, the second transported original single-sided reading mode or the second transported original double-sided reading mode is executed, and the large-sized original M is pulled out from the original tray 33, transported, and discharged to the second discharge tray 49. For example, an original M larger than the minimum standard size A5 is pulled out of the original tray 33, transported, and discharged to the first discharge tray 40, or an original M larger than the minimum standard size A5 is pulled out of the original tray 33, transported, and discharged to the second discharge tray 49.

After that, when the user operates the GUI displayed on the display unit 24 to input a selection instruction via the operation unit 23 to select the stationary document reading mode again, places the document M face down on the second platen glass 52, and operates the start key of the operation unit 23 to input a reading instruction, the control unit 29 repeats S102 and S103. Also, when the user operates the GUI displayed on the display unit 24 to input a selection instruction to select the second transported document single-sided reading mode or the second transported document double-sided reading mode again, places the document M face up on the document tray 33, and operates the start key of the operation unit 23 to input a reading instruction, S104 to S106 are repeated.

Alternatively, the user then operates the GUI displayed on the display unit 24 to input a selection instruction to again select the first transported document single-sided reading mode or the first transported document double-sided reading mode, places the document M on the document tray 33 with its front side facing up, and operates the start key on the operation unit 23 to input a reading instruction, whereupon the control unit 29 executes the first transported document single-sided reading mode or the first transported document double-sided reading mode in the following control procedure.

In this case, the control unit 29 determines that the first transported original single-sided reading mode or the first transported original double-sided reading mode has been selected (S101 "First"), determines the length of the original M based on the detection output of the length sensor 61 provided in the original tray 33, and determines the width of the original M based on the detection output of the width sensor 62 provided in the original tray 33, obtains the size of the original M, and stores this obtained size of the original M in the memory unit 27 (S107).

Then, the control unit 29 determines that the first transported original single-sided reading mode or the first transported original double-sided reading mode has not been selected for the first time since the image forming device 10 was powered on and the image forming device 10 and the image reading device 20 were started (S108 "No").

Based on the detection output of the discharge sensor 67, the control unit 29 determines whether or not there is a document M discharged to the first discharge tray 40 (S119), and if there is no document M discharged to the first discharge tray 40 (S119 "No"), in response to the operation of the start key of the operation unit 23, executes the first transport document one-sided reading mode or the first transport document two-sided reading mode, transports the document M along the path of the document tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40 (see FIG. 4), and causes the first reading unit 41 to read the image of the upward facing front side of the document M, or causes the third reading unit 43 and the first reading unit 41 to read the image of the downward facing back side of the document M and the image of the upward facing front side of the document M (S110). Then, the control unit 29 causes the image forming unit 21 to form the image of the front side of the document M on the recording paper, or causes the image forming unit 21 to form the image of the front side and the image of the back side of the document M on the front and back sides of the recording paper (S111). When the control unit 29 determines that the document M is present on the document tray 33 based on the detection output of the document sensor 68 (S112 "Yes"), it repeats S110 and S111, and when it determines that the document M is not present on the document tray 33 based on the detection output of the document sensor 68 (S112 "No"), it ends the control procedure shown in Figures 7A to 7C.

Therefore, when the first transported original single-sided reading mode or the first transported original double-sided reading mode is selected again and there is no original M discharged to the first discharge tray 40, the first transported original single-sided reading mode or the first transported original double-sided reading mode is executed as normal.

When the control unit 29 determines that there is an original document M discharged to the first discharge tray 40 based on the detection output of the discharge sensor 67 (S119 "Yes"), it determines whether the size of the original document M on the original document tray 33 is larger than the size of the original document M stored in the memory unit 27 (the size of the original document M discharged to the first discharge tray 40) (S120).

Here, when the first transported original single-sided reading mode or the first transported original double-sided reading mode is selected (S101 "first"), the length and width of the original M are determined based on the detection output of the length sensor 61 and the detection output of the width sensor 62 provided in the original tray 33, and the size of the original M is stored in the memory unit 27 (S107). Then, when the first transported original single-sided reading mode or the first transported original double-sided reading mode is executed, the original M of the stored size is transported through the route of the original tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40. Therefore, the size of the original M discharged to the first discharge tray 40 by the execution of the first transported original single-sided reading mode or the first transported original double-sided reading mode is stored in the memory unit 27.

In addition, the control unit 29 stores the size of the original M in the memory unit 27 in S107, and then proceeds to S104 to S106. When the second transported original single-sided reading mode or the second transported original double-sided reading mode is executed, the control unit 29 erases the size of the original M from the memory unit 27. As a result, only the size of the original M discharged to the first discharge tray 40 by executing the first transported original single-sided reading mode or the first transported original double-sided reading mode is stored in the memory unit 27.

For example, if the control unit 29 determines that the size of the document M on the document tray 33 is larger than the size of the document M stored in the memory unit 27 (the size of the document M discharged to the first discharge tray 40) (S120 "Yes"), it prohibits the document M from being transported along the route from the document tray 33 to the common transport path 45 to the straight transport path 46 to the first discharge tray 40, and displays a warning message M1 on the display unit 24 as shown in FIG. 8, urging the user to remove the document M discharged to the first discharge tray 40, and further starts timing the elapsed time T since the warning message M1 was displayed (S121).

The control unit 29 determines whether the start key of the operation unit 23 has been operated (S122), and determines whether there is no document M left on the document tray 33 based on the detection output of the document sensor 68 (S123), and further determines whether the elapsed time T has reached a certain time t (S124).

For example, before the elapsed time T reaches a certain time t (S124 "No"), the control unit 29 determines that the start key of the operation unit 23 has been operated (S122 "Yes"), or determines that there is no document M on the document tray 33 based on the detection output of the document sensor 68 (S123 "Yes"), and executes the first transport document one-sided reading mode or the first transport document two-sided reading mode, transports the document M along the path of the document tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40 (see FIG. 4), and causes the first reading unit 41 to read the image of the upward facing front side of the document M, or causes the third reading unit 43 and the first reading unit 41 to read the image of the downward facing back side of the document M and the image of the upward facing front side of the document M (S110). Then, the control unit 29 causes the image forming unit 21 to form the image of the front side of the document M on the recording paper, or causes the image forming unit 21 to form the image of the front side and the image of the back side of the document M on the front and back sides of the recording paper (S111). When the control unit 29 determines that the document M is present on the document tray 33 based on the detection output of the document sensor 68 (S112 "Yes"), it repeats S110 and S111, and when it determines that the document M is not present on the document tray 33 based on the detection output of the document sensor 68 (S112 "No"), it ends the control procedure shown in Figures 7A to 7C.

In addition, when the elapsed time T reaches a certain time t (S124 "Yes"), the control unit 29 executes the second transported original single-sided reading mode or the second transported original double-sided reading mode without determining that the start key of the operation unit 23 has been operated (S122 "No"), and without determining that there is no original M on the original tray 33 based on the detection output of the original sensor 68 (S123 "No"), and transports the original M through the route of the original tray 33 → common transport path 45 → curved transport path 47 → second discharge tray 49 (see FIG. 5), and causes the second reading unit 12 to read the image of the front side of the original M, or causes the third reading unit 43 and the second reading unit 12 to read the image of the downward facing back side of the original M and the image of the front side of the original M (S104). The control unit 29 causes the image forming unit 21 to form the image of the front side of the original M on the recording paper, or causes the image forming unit 21 to form the image of the front side and the image of the back side of the original M on the front and back sides of the recording paper (S105). When the control unit 29 determines that the document M is present on the document tray 33 based on the detection output of the document sensor 68 (S106 "Yes"), it repeats S104 and S105, and when it determines that the document M is not present on the document tray 33 based on the detection output of the document sensor 68 (S106 "No"), it ends the control procedure shown in Figures 7A to 7C.

Therefore, when the first transported document single-sided reading mode or the first transported document double-sided reading mode is selected again, there is a document M discharged to the first discharge tray 40, and the size of the document M on the document tray 33 is larger than the size of the document M discharged to the first discharge tray 40, a warning message M1 is displayed on the display unit 24, and when the start key is operated or the document M on the first discharge tray 40 is removed, the first transported document single-sided reading mode is executed, and the large-sized document M is pulled out from the document tray 33, transported, and discharged to the first discharge tray 40. Also, when a certain time t has elapsed since the warning message M1 was displayed, the second transported document single-sided reading mode or the second transported document double-sided reading mode is executed, and the large-sized document M is pulled out from the document tray 33, transported, and discharged to the second discharge tray 49.

For example, if the document M on the document tray 33 is of standard size A4 and the document M discharged to the first discharge tray 40 is of standard size B5, the standard size A4 is larger than the standard size B5, so a warning message M1 is displayed on the display unit 24, and when the start key is operated or the standard size B5 document M on the first discharge tray 40 is removed, the standard size A4 document M is pulled out of the document tray 33, transported, and discharged to the first discharge tray 40. Also, when a certain time t has elapsed since the warning message M1 was displayed, the standard size A4 document M is pulled out of the document tray 33, transported, and discharged to the second discharge tray 49.

When the control unit 29 determines that the size of the document M on the document tray 33 is equal to or smaller than the size of the document M discharged to the first discharge tray 40 (S120 "No"), it executes the first transport document one-sided reading mode or the first transport document two-sided reading mode in response to the operation of the start key on the operation unit 23, transports the document M along the path of the document tray 33 → common transport path 45 → straight transport path 46 → first discharge tray 40 (see FIG. 4), and causes the first reading unit 41 to read the image of the upward facing front side of the document M, or causes the third reading unit 43 and the first reading unit 41 to read the image of the downward facing back side of the document M and the image of the upward facing front side of the document M (S125). At the same time, when the document M passes through the common transport path 45, the control unit 29 determines the width of the document M based on the output of the third reading unit (contact image sensor) 43 of the common transport path 45 (S126).

Then, the control unit 29 causes the image forming unit 21 to form an image of the front side of the document M on a recording sheet, or causes the image forming unit 21 to form an image of the front side and an image of the back side of the document M on both sides of the recording sheet (S127).

When the control unit 29 determines that there is an original M on the original tray 33 based on the detection output of the original sensor 68 (S128 "Yes"), it repeats S124 to S127. When it determines that there is no original M on the original tray 33 based on the detection output of the original sensor 68 (S128 "No"), and thus finishes reading the images of all the originals M on the original tray 33, it compares the widths of each original M determined based on the output of the third reading unit 43, and determines whether the width of any original M is smaller than the width of another original M on the page following that original M (S129).

For example, when the control unit 29 determines that the width of any document M is smaller than the width of another document M following the page of the document M (S129 "Yes"), it causes the display unit 24 to display a warning message M2 indicating that small-sized documents M are mixed in with the documents M discharged to the first discharge tray 40 (S130), and ends the control procedure of Figures 7A to 7C. Figure 9 shows an example of the screen of the display unit 24 on which the warning message M2 is displayed.

If the size of the original M on the original tray 33 is equal to or smaller than the size of the original M discharged to the first discharge tray 40, the original M will not be hidden by the discharged original M even if the original M is pulled out of the original tray 33, transported, and discharged to the first discharge tray 40. However, the originals M on the original tray 33 may include originals of various sizes smaller than the size of the original M discharged to the first discharge tray 40. For this reason, the width of each original M pulled out of the original tray 33 is determined, and if the width of any original M is smaller than the width of another original M on the page following that original M, it is assumed that a small original M is sandwiched between larger originals M, and a warning message M2 is displayed on the display unit 24.

In addition, when the control unit 29 determines that the width of any one of the documents M is not smaller than the width of another document M on the page following that document M (S129 "No"), the control unit 29 ends the control procedure of Figures 7A to 7C without displaying the warning message M2 on the display unit 24, since the small document M is not sandwiched between larger documents M.

In this manner, in this embodiment, when control is performed that may cause a situation in which a small-sized document becomes hidden under a larger-sized document on the first output tray 40, or becomes sandwiched between larger-sized documents, making it impossible to view the small-sized document, the user is notified of the situation, and the occurrence of the situation is prevented in advance.

In addition, when the first transported document single-sided reading mode or the first transported document double-sided reading mode is executed in S110 and the document M is transported from the document tray 33 to the common transport path 45 to the straight transport path 46 to the first discharge tray 40, if a jam occurs and the transport of the document M is interrupted, the user performs an operation to clear the jam, then operates the GUI displayed on the display unit 24 to input a selection instruction to select the first transported document single-sided reading mode or the first transported document double-sided reading mode again, places the document M on the document tray 33, and operates the start key of the operation unit 23 to input a reading instruction, but it is preferable that the control unit 29 only performs S110 to S112 and does not display the warning message M1, etc. This is because if the warning message M1 is displayed immediately after the operation to clear the jam, it may cause confusion for the user.

In addition, when a user operates the GUI displayed on the display unit 24 to perform user authentication and start using the image forming device 10 and image reading device 20, the control unit 29 preferably displays warning message M1 once when executing the first transported original single-sided reading mode or the first transported original double-sided reading mode, and then performs only S110 to S112 and does not display warning message M1, etc. This is to prevent the warning message M1 from being displayed repeatedly and unnecessarily to the same user.

In addition, in the above embodiment, the straight conveying path 46 conveys documents that are difficult to bend, such as cards, postcards, and photographs, or documents of small size, and these documents are read by the third reading unit 43 or the first reading unit 41. A control procedure is described for preventing the above-mentioned situation from occurring when a document larger than these documents is then conveyed along the straight conveying path 46 and read by the third reading unit 43 or the first reading unit 41. However, even when multiple documents are conveyed along the curved conveying path 47 and read by the third reading unit 43 or the second reading unit 12, there are cases in which the document read first is small in size (for example, postcard size, A5 size, etc.) and the document read subsequently is larger in size (A4 size, B4 size, etc.), in which case the above-mentioned situation can occur, just as in the case of the straight conveying path 46. For this reason, the control procedure for preventing the above-mentioned situation from occurring can also be applied when multiple documents are transported along the curved transport path 47, read by the third reading unit 43 or the second reading unit 12, and discharged to the second discharge tray 49. Alternatively, the control procedure for preventing the above-mentioned situation from occurring can also be applied to an image reading device or image forming device that does not have the straight transport path 46 and the mechanisms therefor, but has the curved transport path 47, the third reading unit 43, the second reading unit 12, and the second discharge tray 49.

Note that the configuration and processing of the above embodiment described using Figures 1 to 9 are merely examples of the present invention, and are not intended to limit the present invention to these configurations and processing.

REFERENCE SIGNS LIST 10 Image forming apparatus 12 Second reading section 20 Image reading apparatus 21 Image forming section 23 Operation section 24 Display section 25 Touch panel 26 Image memory 27 Storage section 28 Control unit 29 Control section 31 Document transport section 32 Document reading section 41 First reading section 43 Third reading section 61 Length sensor 62 Width sensor 67 Paper discharge sensor 68 Document sensor

Claims (11)

a document tray on which documents are placed;
a document transport unit that pulls out the document from the document tray and transports the document through a transport path;
a reading unit that reads an image of the document being transported through the transport path;
a size detection unit that detects the size of the document placed on the document tray;
a paper discharge tray for receiving the document discharged from a discharge port of the transport path;
a document detection unit for detecting a document on the discharge tray;
an operation unit through which a user inputs an instruction to read the document on the document tray;
A display unit;
A storage unit;
a control unit, when an instruction to read a first original on the original tray is given by the operation unit, storing the size of the first original on the original tray detected by the size detection unit in the memory unit, transporting the first original from the original tray to the first discharge tray through the transport path, and causing the reading unit to read an image of the first original, and when an instruction to read a second original on the original tray is input by operating the operation unit, determining whether or not the first original on the discharge tray has been detected by the original detection unit, and when it is determined that the first original on the discharge tray has been detected, determining whether or not the size of the second original on the original tray detected by the size detection unit is larger than the size of the first original stored in the memory unit, and when it is determined that the size of the second original is larger than the size of the first original, causing the display unit to display an indication that the first original is on the discharge tray. The image reading device according to claim 1, wherein the control unit, when determining that the size of the second document on the document tray detected by the size detection unit is larger than the size of the first document stored in the storage unit, causes the display unit to display that the first document is on the discharge tray, and prohibits the second document from being transported from the document tray to the discharge tray through the transport path. The image reading device according to claim 2, wherein, after the control unit prohibits the second document from being transported from the document tray through the transport path to the discharge tray, when the operation unit is operated to instruct reading of the second document on the document tray again, the control unit causes the second document to be transported from the document tray through the transport path to the discharge tray and causes the reading unit to read an image of the second document. The image reading device according to claim 2, wherein, after the control unit prohibits the second document from being transported from the document tray through the transport path to the discharge tray, when the document detection unit no longer detects the first document on the discharge tray, the control unit causes the second document to be transported from the document tray through the transport path to the discharge tray and causes the reading unit to read an image of the second document. The control unit causes the second document to be transported from the document tray through the transport path to the discharge tray, and when the image of the second document is read by the reading unit, if an error occurs in transporting the second document through the transport path and transport through the transport path is interrupted, the control unit does not cause the display unit to display that a first document is on the discharge tray even if the error is eliminated and the operation unit is operated to instruct the reading of another document on the document tray. The image reading device according to claim 3. The image reading device according to claim 1, wherein, when the power supply of the image reading device is switched from off to on and the operation unit is operated to instruct reading of the document on the document tray for the first time, the control unit determines whether or not a first document on the discharge tray is detected by the document detection unit, and if it determines that the first document on the discharge tray is detected, determines whether or not the size of a second document on the document tray detected by the size detection unit is larger than a preset minimum size, and if the size of the second document on the document tray is larger than the minimum size, causes the display unit to display that a first document is on the discharge tray. The image reading device according to claim 1, wherein the control unit performs user authentication based on an operation performed by the operation unit, and when the reading unit reads the document on the document tray in response to the user authentication, the control unit displays, only once on the display unit, that the first document is on the first discharge tray. a document tray on which documents are placed;
a document transport unit that pulls out the document from the document tray and transports the document through a transport path;
a reading unit that reads an image of the document being transported through the transport path;
a size detection unit that detects the size of the document on the document tray and the size of the document being transported through the transport path;
a paper discharge tray for receiving the document discharged from a discharge port of the transport path;
a document detection unit for detecting a document on the discharge tray;
an operation unit through which a user inputs an instruction to read the document on the document tray;
A display unit;
A storage unit;
When an instruction to read a first document on the document tray is given by the operation unit, the size of the first document on the document tray detected by the size detection unit is stored in the storage unit, the first document is transported from the document tray to the first discharge tray through the transport path, and an image of the first document is read by the reading unit. When an instruction to read a second document on the document tray is input by operating the operation unit, the document detection unit determines whether or not the first document on the first discharge tray has been detected, and if it is determined that the first document on the first discharge tray has been detected, the size of the second document on the document tray detected by the size detection unit is stored in the storage unit. a control unit that determines whether the size of the first original is equal to or smaller than the size of the first original, and if it is determined that the size of the second original is equal to or smaller than the size of the first original, sequentially transports a plurality of second originals from the original tray through the transport path to the first discharge tray, causes the reading unit to sequentially read the images of each second original, and causes the size detection unit to detect the size of each second original being transported through the transport path, and if the size of any second original is smaller than the size of another second original after the page of the second original, causes the display unit to display that a smaller sized second original is mixed in among the second originals on the first discharge tray. a document tray on which documents are placed;
a document transport section that draws out the document from the document tray and transports the document through a straight transport path or a curved transport path;
a first reading unit that reads an image of a document being transported through the linear transport path;
a second reading unit that reads an image of the document being transported through the curved transport path;
a size detection unit that detects the size of the document placed on the document tray;
a first discharge tray for receiving the document discharged from a discharge port of the linear transport path;
a second discharge tray for receiving the document discharged from a discharge opening of the curved transport path;
a document detection unit that detects a document on a first discharge tray;
an operation unit into which a user inputs an instruction as to whether the document is to be transported through the straight transport path or the curved transport path;
A display unit;
A storage unit;
and a control unit, when the linear transport path is instructed by operation of the operation unit, storing the size of a first original on the original tray detected by the size detection unit in the memory unit, transporting the first original from the original tray to a first discharge tray through the linear transport path, and causing the first reading unit to read an image of the first original, and, when the linear transport path is again instructed by operation of the operation unit, determining whether or not a first original on the first discharge tray has been detected by the original detection unit, and when it is determined that the first original on the first discharge tray has been detected, determining whether or not a size of a second original on the original tray detected by the size detection unit is larger than the size of the first original stored in the memory unit, and when it is determined that the size of the second original is larger than the size of the first original, causing the display unit to display that a first original is on the first discharge tray. The image reading device according to claim 9, wherein the control unit, when causing the display unit to indicate that the first document is on the first discharge tray, causes the second document to be transported from the document tray to the second discharge tray through the curved transport path and causes the second reading unit to read an image of the second document. An image reading device according to any one of claims 1 to 10,
an image forming section that forms an image of the document read by the image reading device on a recording sheet;