Image reading device and control method for the image reading device

Abstract

To provide an image reading device that can achieve a function related to reading of an image according to power consumption, and a method for controlling an image reading device.SOLUTION: A low output mode is a mode that is controllable in a connection state in which a low power supply USB instrument that can supply power with a power value included in a low power range is connected. A high output mode is a mode that is controllable in a connection state in which a high power supply USB instrument that can supply power with a power value included in a high power range higher than the low power range is connected. In the low output mode, a control unit does not execute reading of an image at a second reading speed faster than a first reading speed, but can execute the reading of an image at the first reading speed.SELECTED DRAWING: Figure 4

Description

Technical Field

[0004] , ,

[0005] , , ,

[0001] The present invention relates to an image reading apparatus configured to read an image from a document and a control method for the image reading apparatus.

Background Art

[0002] For example, Patent Document 1 discloses an image reading apparatus that can be connected to a USB device. In the image reading apparatus, power can be supplied from the USB device when a USB device such as a terminal device is connected. Such an image reading apparatus can be controlled to any one of a plurality of modes with different power consumptions in accordance with the connection to the USB device. The plurality of modes include a reference mode and a power saving mode with lower power consumption than the reference mode. In the image reading apparatus, it is possible to control to the power saving mode when an image is not being read. In the image reading apparatus, when an image reading is instructed while being controlled in the power saving mode, it is possible to control to the reference mode.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in such an image reading apparatus, when an image reading is instructed in a mode with low power consumption, the mode shifts to a mode with high power consumption. For this reason, the power consumption as an image reading apparatus increases. Thus, in an image reading apparatus, it is desired to realize functions related to image reading according to the power consumption.

Means for Solving the Problems

[0005] An image reading device that solves the above problems comprises a reading unit configured to read an image from a document, and a control unit configured to perform control related to image reading, wherein the control unit is controllable to any of a plurality of modes, the plurality of modes including a low-power mode and a high-power mode, the low-power mode is a mode that can be controlled in a connected state in which a low-power USB device capable of supplying power values ​​within a low-power range is connected, and the high-power mode is a mode that can be controlled in a connected state in which a high-power USB device capable of supplying power values ​​within a high-power range higher than the low-power range is connected, the reading unit can read an image at either a first reading speed or a second reading speed faster than the first reading speed, the control unit can prevent image reading at the second reading speed but allow image reading at the first reading speed in the low-power mode, and can allow image reading at the first reading speed and image reading at the second reading speed in the high-power mode.

[0006] A control method for an image reading device that solves the above problems is a control method for an image reading device equipped with a reading unit configured to read an image from a document, wherein the device is controllable to any of a plurality of modes, including a low-output mode that can be controlled when a low-power USB device capable of supplying power values ​​within a low-power range is connected, and a high-output mode that can be controlled when a high-power USB device capable of supplying power values ​​within a high-power range higher than the low-power range is connected, and in the low-output mode, the device is not allowed to read an image at a second reading speed faster than the first reading speed, but it is allowed to read an image at the first reading speed, and in the high-output mode, the device is allowed to read an image at the first reading speed and also allow it to read an image at the second reading speed. [Brief explanation of the drawing]

[0007] [Figure 1] This is a side view of the image reading device in its first orientation. [Figure 2] This is a side view of the image reading device in the second orientation. [Figure 3] This is a block diagram showing the electrical configuration of an image reading device. [Figure 4] This is a schematic diagram showing the control details for each of the multiple modes. [Figure 5] This is a timing chart showing the timing of sensor control. [Figure 6] This is a timing chart showing the timing of image reading and image data output. [Figure 7] This is a flowchart showing the startup mode setting process. [Figure 8] This is a flowchart showing the battery identification process. [Figure 9] This flowchart shows the process for setting the normal mode. [Figure 10] This is a schematic diagram showing the control table. [Figure 11] This is a flowchart showing the charging control process. [Figure 12] This is a timing chart showing the timing of image reading and image data output. [Figure 13] This is a timing chart showing the timing of image reading and image data output. [Modes for carrying out the invention]

[0008] [First Embodiment] The following describes one embodiment of an image reading device with reference to the figures. The image reading device is, for example, a sheet-fed scanner in which a fixed reading unit reads a document such as paper or film that is being transported. The image reading device is not limited to a sheet-fed scanner; a flatbed scanner may also be used.

[0009] <Configuration of the image reading device 11> As shown in Figures 1 and 2, the image reading device 11 comprises a housing 12 and a base 13. The housing 12 is supported by the base 13. The base 13 is installed, for example, on a horizontal surface. The housing 12 is configured to be rotatable relative to the base 13.

[0010] The housing 12 is configured to allow switching of orientation. The housing 12 is configured to switch orientation by, for example, rotation relative to the base 13. The housing 12 switches between, for example, a first orientation as shown in Figure 1 and a second orientation as shown in Figure 2. The housing 12 is configured so that its tilt relative to the base 13 changes between the first orientation and the second orientation. In this way, the image reading device 11 can reduce the foot space of the image reading device 11 when the housing 12 is in the first orientation compared to when the housing 12 is in the second orientation.

[0011] The housing 12 includes a supply port 14. The supply port 14 is an opening into which the original document D is supplied before scanning. The housing 12 may also include a plurality of output ports 15. The plurality of output ports 15 are openings through which the scanned original document D is ejected. The plurality of output ports 15 include a first output port 15A and a second output port 15B.

[0012] The image reading device 11 includes a paper feed tray 16. The paper feed tray 16 extends from inside the housing 12 to outside the housing 12 through a supply opening 14. The paper feed tray 16 can hold original documents D before scanning. The paper feed tray 16 is slidable in the direction in which original documents D before scanning are fed. The paper feed tray 16 corresponds to an example of a first tray.

[0013] The image reading device 11 includes an output tray 17. The output tray 17 extends from the inside of the housing 12 to the outside of the housing 12 through a first output port 15A. The output tray 17 can hold scanned documents D. The output tray 17 is slidable in the direction in which scanned documents D are ejected. The output tray 17 corresponds to an example of a second tray.

[0014] The image reading device 11 includes a conveyance path 18. The conveyance path 18 is a path along which the document D is conveyed. The conveyance path 18 extends inside the housing 12. The image reading device 11 includes, for example, a first conveyance path 18A and a second conveyance path 18B. The first conveyance path 18A is the path indicated by the dashed line in FIG. 1. The second conveyance path 18B is the path indicated by the dashed line in FIG. 2.

[0015] As shown in FIG. 1, the first conveyance path 18A extends from the supply port 14 toward the first discharge port 15A. The first conveyance path 18A includes, for example, a common conveyance path 19. The common conveyance path 19 is a path common to the first conveyance path 18A and the second conveyance path 18B. The common conveyance path 19 extends linearly or in a straight line. The direction in which the common conveyance path 19 extends is the sub-scanning direction D1. The common conveyance path 19 is a path passing through the reading area SA. The first conveyance path 18A includes a curved path 20A. The curved path 20A extends from the common conveyance path 19. The curved path 20A curves, for example, in a U shape. The first conveyance path 18A is, for example, a path along which the document D is conveyed when the housing 12 is in the first posture.

[0016] As shown in FIG. 2, the second conveyance path 18B extends from the supply port 14 toward the second discharge port 15B. The second conveyance path 18B includes, for example, the common conveyance path 19. The second conveyance path 18B includes a straight path 20B. The straight path 20B extends from the common conveyance path 19. The straight path 20B is a path that extends linearly or in a straight line. The second conveyance path 18B is, for example, a path along which the document D is conveyed when the housing 12 is in the second posture. Thus, the image reading device 11 is configured such that the path along which the document D is conveyed is switched when the posture of the housing 12 is switched.

[0017] Thus, the image reading device 11 is configured such that the angle of the common conveyance path 19 with respect to the horizontal plane changes when the posture of the housing 12 is switched. In particular, the image reading device 11 may be configured such that when the housing 12 is in the second posture, the angle of the common conveyance path 19 with respect to the horizontal plane is gentler than when the housing 12 is in the first posture.

[0018] The image reading device 11 includes a transport unit 21. The transport unit 21 is configured to transport the document D in the sub-scanning direction D1. In particular, the transport unit 21 is capable of transporting thin paper documents D. The transport unit 21 is capable of transporting thick paper documents D. The transport unit 21 is capable of transporting a carrier sheet with the document D sandwiched inside.

[0019] The transport unit 21 includes one or more rollers. The transport unit 21 comprises, for example, a paper feed roller 22, a first roller pair 23, a second roller pair 24, and a third roller pair 25. The paper feed roller 22 is located at the upstream end of the transport path 18. The paper feed roller 22 supplies the original documents D placed on the paper feed tray 16 one by one into the housing 12 via the supply port 14.

[0020] The first roller pair 23 is located downstream of the paper feed roller 22 in the transport path 18. The first roller pair 23 comprises a first drive roller 23A and a first separation roller 23B. The friction coefficient of the outer surface of the first separation roller 23B with respect to the original document D is greater than that of the first drive roller 23A. The first separation roller 23B rotates at a slightly lower rotational speed than the first drive roller 23A. As a result, even if multiple original documents D are fed together from the paper feed roller 22, the first roller pair 23 separates the bottommost sheet and transports it downstream in the transport path 18.

[0021] The second roller pair 24 is located downstream of the first roller pair 23 in the transport path 18. The second roller pair 24 is located upstream of the reading area SA in the transport path 18. The second roller pair 24 comprises a second drive roller 24A and a second driven roller 24B. The second drive roller 24A is rotationally driven to transport the document D at a predetermined transport speed. The second driven roller 24B rotates together with the rotation of the second drive roller 24A.

[0022] The third roller pair 25 is located downstream of the second roller pair 24 in the transport path 18. The third roller pair 25 is located downstream of the reading area SA in the transport path 18. The third roller pair 25 comprises a third drive roller 25A and a third driven roller 25B. The third drive roller 25A is rotationally driven to transport the document D at a predetermined transport speed. The third driven roller 25B rotates together with the rotation of the third drive roller 25A.

[0023] The transport unit 21 includes a route switching member 26. The route switching member 26 is, for example, a flap. The route switching member 26 switches the route through which the document D is transported to either the first transport route 18A or the second transport route 18B. The route switching member 26 switches the route through which the document D is transported by blocking either the first transport route 18A or the second transport route 18B. When the route switching member 26 blocks the first transport route 18A, it guides the document D to the second transport route 18B. When the route switching member 26 blocks the second transport route 18B, it guides the document D to the first transport route 18A.

[0024] The route switching member 26 is, for example, linked to the orientation of the housing 12. When the housing 12 is in the first orientation, the route switching member 26 blocks the second transport route 18B. When the housing 12 is in the second orientation, the route switching member 26 blocks the first transport route 18A. The route switching member 26 may be displaced independently of the orientation of the housing 12. That is, the route may be switched by the route switching member 26 regardless of the orientation of the housing 12.

[0025] The image reading device 11 includes one or more sensors that perform detection related to image reading. Specifically, the image reading device 11 may include a first document sensor 31. The first document sensor 31 detects the presence or absence of a document D in the paper feed tray 16. The first document sensor 31 may be a contact type sensor with a lever, for example, but it may also be a non-contact sensor such as an optical sensor.

[0026] The image reading device 11 may also be equipped with a document protection sensor 32. The document protection sensor 32 detects the position of the document D in the paper feed tray 16. In particular, the document protection sensor 32 detects that the document D being fed into the feed opening 14 is transported at an angle in order to protect the document D. The document protection sensor 32 may be a non-contact sensor such as an optical sensor, but it may also be a contact sensor with a lever.

[0027] The image reading device 11 may include a document thickness sensor 33. The document thickness sensor 33 detects the thickness of the document D placed on the paper feed tray 16. The document thickness sensor 33 may be capable of detecting, for example, any of the document types: thin paper document D, thick paper document D, and carrier sheet. The document thickness sensor 33 is located, for example, inside the housing 12. The document thickness sensor 33 may be, for example, an ultrasonic sensor or an optical sensor.

[0028] The image reading device 11 may also include a carrier sheet sensor 34. The carrier sheet sensor 34 is provided between the first drive roller 23A and the second drive roller 24A. The carrier sheet sensor 34 detects the carrier sheet that holds the document D. The carrier sheet is a sheet configured to hold the document D between transparent films. The carrier sheet can transport the document D along the transport path 18 while holding it, for example, an extremely small document D. The carrier sheet sensor 34 may be, for example, an optical sensor. The carrier sheet sensor 34 detects identification parts such as marks on the document D or the carrier sheet.

[0029] The image reading device 11 may also be equipped with a double feed sensor 35. The double feed sensor 35 is located between the first drive roller 23A and the second drive roller 24A. The double feed sensor 35 is located downstream of the carrier sheet sensor 34 in the transport path 18. The double feed sensor 35 detects double feeding of the original document D. Double feeding of the original document D means that multiple original documents D are transported overlapping each other.

[0030] The image reading device 11 may also include a second document sensor 36. The second document sensor 36 is located downstream of the second roller pair 24 in the transport path 18. The second document sensor 36 detects the presence or absence of a document D being transported by the second roller pair 24. The second document sensor 36 may be a contact-type sensor with a lever, for example, or a non-contact sensor such as an optical sensor.

[0031] The image reading device 11 may include an attitude sensor 37. The attitude sensor 37 detects the attitude of the housing 12. The attitude sensor 37 may include a first attitude sensor 37A and a second attitude sensor 37B, but may also consist of a single sensor. The first attitude sensor 37A detects that the housing 12 is in a first attitude. The first attitude sensor 37A may be configured to detect, for example, a path switching member 26 that blocks the second transport path 18B. The second attitude sensor 37B detects that the housing 12 is in a second attitude. The second attitude sensor 37B may be configured to detect, for example, a path switching member 26 that blocks the first transport path 18A.

[0032] The attitude sensor 37 is not limited to a sensor that detects the path switching member 26; for example, it may be a gyro sensor. If the attitude sensor 37 is a gyro sensor, the image reading device 11 may also be equipped with a separate sensor that detects the position of the path switching member 26.

[0033] The image reading device 11 comprises one or more reading units 40. Each reading unit 40 is configured to read an image from a document D. The reading unit 40 reads an image from the document D being transported along a common transport path 19 in the reading area SA. The reading unit 40 is housed in a housing 12.

[0034] The image reading device 11 includes, for example, two reading units 40. The two reading units 40 are positioned so as to straddle a common transport path 19. The two reading units 40 face each other. The two reading units 40 each read different sides of the original document D. One of the two reading units 40 reads the front surface of the original document D. The other reading unit 40 reads the back surface of the original document D. As a result, the image reading device 11 reads either one side or both sides of the original document D.

[0035] The reading unit 40 comprises a light source 41, an image sensor 42, and a background plate 43. The light source 41 is, for example, an LED or a fluorescent lamp. The light source 41 irradiates light toward the opposing background plate 43.

[0036] The image sensor 42 is aligned in the main scanning direction D2. The image sensor 42 is modular. The image sensor 42 is, for example, a contact-type image sensor. More specifically, the image sensor 42 is a CMOS image sensor. The image sensor 42 converts the received light into photoelectric energy. The image sensor 42 outputs an output signal with a value corresponding to the amount of light received.

[0037] The image sensor 42 may be a monochrome sensor or a color sensor. The reading unit 40 may be configured to read the original document D in full color. For example, the reading unit 40 may be configured to read the original document D using three colors: RGB. The reading unit 40 may also be configured to read the original document D in grayscale.

[0038] The background plate 43 faces, for example, the light source 41 and image sensor 42 of another reading unit 40. The background plate 43 reflects the light emitted from the light source 41 and directs it into the image sensor 42. The background plate 43 is read together with the document D by the image sensor 42. The background plate 43 is read as a background together with the document D by the image sensor 42. The background plate 43 is not limited to white; for example, it may be gray.

[0039] <Electrical configuration of image reading device 11> Next, the electrical configuration of the image reading device 11 will be described with reference to Figure 3. As shown in Figure 3, the image reading device 11 includes a control unit 50. The control unit 50 comprehensively controls the image reading device 11 and may control various operations performed by the image reading device 11. In other words, the control unit 50 is configured to perform control related to image reading. The control unit 50 may include one or more processors that execute various processes according to a program, one or more dedicated hardware circuits such as application-specific integrated circuits that execute at least some of the various processes, or a combination thereof. The processor includes a CPU and memory such as RAM and ROM, and the memory stores program code or instructions configured to cause the CPU to execute processing. Memory, or computer-readable media, includes any readable media that can be accessed by a general-purpose or dedicated computer. The control unit 50 may also include a System on a Chip (SOC).

[0040] The image reading device 11 includes an operating unit 27. The operating unit 27 is located on the housing 12. The operating unit 27 includes a plurality of switches that can be operated by the user. The plurality of switches include a power switch, a start switch, and a stop switch.

[0041] The image reading device 11 includes a notification unit 28. The notification unit 28 is provided in the housing 12. The notification unit 28 may be a display unit such as an LED. The notification unit 28 is configured to provide notifications related to image reading. The notification unit 28 displays information related to image reading, such as power on / off status and mode type. In this way, the notification unit 28 notifies the controlled mode.

[0042] The image reading device 11 comprises a touch panel 29 and a liquid crystal display unit 30. The touch panel 29 is provided on the housing 12. The touch panel 29 has a touch area that can be operated by the user. The liquid crystal display unit 30 may be a display unit made of, for example, a liquid crystal panel. The liquid crystal display unit 30 is configured to display an image at a position corresponding to the touch area of ​​the touch panel 29. The liquid crystal display unit 30 displays information related to image reading, such as setting information. The liquid crystal display unit 30 can display more detailed information than the notification unit 28.

[0043] The transport unit 21 includes a feed motor 44 and a transport motor 45. The feed motor 44 is a power source for rotating the paper feed roller 22 and the first drive roller 23A. The transport motor 45 is a power source for rotating the first separation roller 23B, the second drive roller 24A and the third drive roller 25A.

[0044] The image reading device 11 may include an encoder 46. The encoder 46 is located inside the housing 12. The encoder 46 may be, for example, a rotary encoder. The encoder 46 may be capable of detecting the rotation of the second drive roller 24A, but may also be capable of detecting the rotation of other rollers. The encoder 46 outputs a detection signal containing a number of pulses proportional to the amount of rotation of the second drive roller 24A.

[0045] The image reading device 11 includes a paper feed tray motor 47. The paper feed tray motor 47 is a drive source that can move the paper feed tray 16. The paper feed tray motor 47 is an example of a first tray drive source.

[0046] The image reading device 11 includes a paper output tray motor 48. The paper output tray motor 48 is a drive source that can move the paper output tray 17. The paper output tray motor 48 is an example of a second tray drive source.

[0047] The image reading device 11 includes a posture drive motor 49. The posture drive motor 49 is a power source that drives the housing 12 so that its posture can be changed. The posture drive motor 49 is an example of a housing drive source.

[0048] The control unit 50 is connected to the operation unit 27, the notification unit 28, the touch panel 29, and the liquid crystal display unit 30. The control unit 50 can receive operation signals from the operation unit 27. The control unit 50 can output notification signals to the notification unit 28. The control unit 50 can receive touch signals from the touch panel 29. The control unit 50 can control whether the touch panel 29 is enabled or disabled. The control unit 50 can output signals for displaying images to the liquid crystal display unit 30. The control unit 50 can control whether the liquid crystal display unit 30 is enabled or disabled.

[0049] The control unit 50 is connected to the first document sensor 31, the document protection sensor 32, the document thickness sensor 33, the carrier sheet sensor 34, the double feed sensor 35, the second document sensor 36, the posture sensor 37, and the encoder 46. In Figure 3, the carrier sheet sensor 34 is shown as the CS sensor. The control unit 50 can receive detection signals from the first document sensor 31, the document protection sensor 32, the document thickness sensor 33, the carrier sheet sensor 34, the double feed sensor 35, the second document sensor 36, the posture sensor 37, and the encoder 46. The control unit 50 can control whether to enable or disable the first document sensor 31, the document protection sensor 32, the document thickness sensor 33, the carrier sheet sensor 34, the double feed sensor 35, the second document sensor 36, the posture sensor 37, and the encoder 46.

[0050] The control unit 50 is connected to the feed motor 44, the transport motor 45, the paper feed tray motor 47, the paper output tray motor 48, and the attitude drive motor 49. The control unit 50 can output signals to drive the feed motor 44, the transport motor 45, the paper feed tray motor 47, the paper output tray motor 48, and the attitude drive motor 49. The feed motor 44 may consist of, for example, one motor or multiple motors. The transport motor 45 may consist of, for example, one motor or multiple motors. The paper feed tray motor 47 may consist of, for example, one motor or multiple motors. The paper output tray motor 48 may consist of, for example, one motor or multiple motors. The attitude drive motor 49 may consist of, for example, one motor or multiple motors.

[0051] The control unit 50 includes a timing generator 55. In Figure 3, the timing generator 55 is indicated as TG. The timing generator 55 outputs a pulse signal indicating the reading operation timing to the reading unit 40.

[0052] The control unit 50 includes an analog front end 56. In Figure 3, the analog front end 56 is indicated as AFE. The analog front end 56 converts the image signal from the image sensor 42 from an analog signal to a digital signal.

[0053] The control unit 50 is connected to the reading unit 40. The control unit 50 can instruct the reading unit 40 to read an image via the timing generator 55. The control unit 50 can receive an image signal from the reading unit 40 via the analog front end 56. The control unit 50 can adjust the read control clock supplied to the timing generator 55 and the analog front end 56. The timing generator 55 and the analog front end 56 are driven at a period based on the read control clock supplied from the control unit 50.

[0054] The control unit 50 comprises various functional units that operate by executing a program. Specifically, the control unit 50 includes a main control unit 51, a transport control unit 52, a reading control unit 53, an image processing unit 54, a first wireless communication unit 57, a second wireless communication unit 58, and a wired communication unit 59. The main control unit 51 comprehensively controls the image reading device 11.

[0055] The transport control unit 52 controls the transport of the document D along the transport path 18. The transport control unit 52 drives the feed motor 44 and the transport motor 45 according to the instructions of the main control unit 51. In particular, the transport control unit 52 drives the feed motor 44 and the transport motor 45 to transport the document D at a transport speed corresponding to the reading speed. In this embodiment, ppm (papers per minute), which is the number of standard-size documents D that can be read in one minute, is used as the unit of reading speed. The reading speed may be specified based on the reading instruction, or it may be set in advance in the control unit 50 rather than for each reading instruction.

[0056] To give a specific example, when the reading speed is 40 ppm, the transport control unit 52 transports the document D at a higher speed than when the reading speed is 30 ppm. When the reading speed is 30 ppm, the transport control unit 52 transports the document D at a higher speed than when the reading speed is 5 ppm.

[0057] The reading control unit 53 controls the reading unit 40 via the timing generator 55. In particular, the reading control unit 53 controls the emission of light from the light source 41. The reading control unit 53 controls the image sensor 42 to perform a reading operation. As a result, the reading control unit 53 controls the reading unit 40 to read the image of the original document D.

[0058] Furthermore, the reading control unit 53 causes the reading unit 40 to read the image at a reading speed of 40 ppm, 30 ppm, or 5 ppm. In other words, the reading unit 40 can read the image at any of several reading speeds, including 40 ppm, 30 ppm, and 5 ppm. 5 ppm is an example of a first reading speed. 40 ppm is an example of a second reading speed. 30 ppm is an example of a third reading speed.

[0059] The image processing unit 54 processes the image data of the image read by the reading unit 40. In particular, the image processing unit 54 can perform predetermined corrections on the image data of the image read by the reading unit 40. The image processing unit 54 includes an image data storage unit 54A. The image data storage unit 54A can store image data of images read from at least a predetermined number of original documents D. The predetermined number of original documents may be, for example, one or more.

[0060] The image processing unit 54 can output the corrected image data to an external device. External devices include, for example, USB (Universal Serial Bus) memory, personal computers, mobile terminals, and server devices. Communication with the external device can be wired or wireless. Wired communication includes USB communication via a USB cable, but may also include communication via other communication cables such as LAN (Local Area Network) cables.

[0061] The first wireless communication unit 57 performs control for performing the first wireless communication. The first wireless communication may be, for example, wireless communication that enables interoperability between USB devices using the IEEE 802.11 standard. In other words, the first wireless communication may be, for example, Wi-Fi (registered trademark).

[0062] The second wireless communication unit 58 performs control for conducting the second wireless communication. The second wireless communication may be, for example, Bluetooth (registered trademark). The second wireless communication has a lower communication speed but consumes less power than the first wireless communication.

[0063] The wired communication unit 59 performs control for wired communication. Wired communication may include, for example, communication via a USB cable, or communication via another communication cable such as a LAN cable. Wired communication consumes less power than the first wireless communication and the second wireless communication.

[0064] When a reading instruction is received, the image reading device 11 can transport one or more originals D placed in the paper feed tray 16 one at a time and perform a reading operation to read images from the originals D. In other words, the image reading device 11 can perform a reading operation to read images from one or more originals D based on a single reading instruction. The reading instruction may be given from the operation unit 27, from the touch panel 29, or from a personal computer or mobile terminal device.

[0065] The image reading device 11 includes a power supply circuit 60 and a connection section 61. The power supply circuit 60 supplies power to various components of the image reading device 11 based on the power supplied via the connection section 61. The connection section 61 can be connected to an external power supply source for the image reading device 11. The control unit 50 is connected to the power supply circuit 60 and the connection section 61. The power supply circuit 60 is connected to the connection section 61.

[0066] The power supply circuit 60 includes a capacitor 60A. Capacitor 60A is a capacitor capable of storing the power supplied to various components. In particular, capacitor 60A has a capacity capable of compensating for the power consumed due to the execution of polling in the first wireless communication. That is, capacitor 60A may include a capacitor with a capacity capable of compensating for the power consumed due to the execution of polling in the first wireless communication. Furthermore, capacitor 60A has a capacity capable of compensating for the power consumed due to the execution of polling in the second wireless communication. That is, capacitor 60A may include a capacitor with a capacity capable of compensating for the power consumed due to the execution of polling in the second wireless communication.

[0067] To give a specific example, in the polling process of the first wireless communication, if 0.25A is consumed over 200μs, the power consumption will be 50μJ. In this case, a 60A capacitor would need a capacitance of approximately 10μF to compensate for the power consumption of 50μJ.

[0068] The connection section 61 includes an AC adapter connection section 62, a battery connection section 63, and a USB connection section 64. The AC adapter connection section 62 can be connected to an AC adapter cable. In other words, the AC adapter connection section 62 can be connected to an AC adapter as a power supply source via an AC adapter cable. It can also be said that the AC adapter connection section 62 can be connected to a commercial power supply as a power supply source via an AC adapter cable and an AC adapter.

[0069] The battery connection section 63 can be connected to a battery cable. In other words, the battery connection section 63 can be connected to a battery as a power supply source via a battery cable. The battery can be powered as a power supply source, but it can also be recharged. The battery connection section 63 may be dedicated to the battery, or it may be possible to insert and detach a USB cable into it.

[0070] The USB connection section 64 can be connected to a USB cable. In other words, the USB connection section 64 can be connected to a USB device as a power supply via a USB cable. USB devices include, for example, USB memory sticks, personal computers, and portable terminal devices.

[0071] The control unit 50 performs enumeration with the USB device connected via the USB connection unit 64 and the USB cable. In particular, the control unit 50 performs enumeration with the USB device when the power is turned on. The control unit 50 also performs enumeration with the USB device when there is a change in the connection state with the USB device. Based on the results of the enumeration, the control unit 50 determines the connection state with the USB device and performs control according to one of the USB standards.

[0072] USB standards include USB 2.0, USB 3.0, USB-BC (Battery Charging), and USB-PD (Power Delivery). These USB standards differ in the power they can supply and their communication speeds. For example, USB 2.0 can supply 2.5W of power, USB 3.0 can supply 4.5W, USB-BC can supply 7.5W, and USB-PD can supply 15W or more. While USB-PD is specifically capable of supplying 15W, it is not limited to this; it may also be capable of supplying 27W, 45W, 60W, 100W, etc. Note that AC adapters may be capable of supplying 15W, and batteries may be capable of supplying 7.5W.

[0073] Furthermore, USB connector standards include, for example, Type-A, Type-B, Type-C, miniUSB, and MicroUSB. While the USB connection port 64 is not limited to any particular type, it is preferable to use Type-C when employing USB-PD.

[0074] In this embodiment, when the USB standard is determined to be USB 3.0 as a result of enumeration with a USB device, it is said that the device is connected to a low-power USB device. When the USB standard is determined to be USB-BC, it is said that the device is connected to a medium-power USB device. When the USB standard is determined to be USB-PD, it is said that the device is connected to a high-power USB device. In addition, a power range of 4.5W or more and less than 7.5W may be indicated as the low-power range. A power range of 7.5W or more and less than 15W may be indicated as the medium-power range. A power range of 15W or more may be indicated as the high-power range.

[0075] Thus, low-power USB devices can supply power values ​​within the low-power range. Medium-power USB devices can supply power values ​​within the medium-power range. High-power USB devices can supply power values ​​within the high-power range. AC adapters can supply power values ​​within the high-power range. Batteries can supply power values ​​within the medium-power range.

[0076] Low-power USB devices are an example of a third-category device. High-power USB devices and AC adapters are an example of a second-category device. Medium-power USB devices and batteries are an example of a first-category device. The low-power range is an example of a third-category power range. The high-power range is an example of a second-category power range. The medium-power range is an example of a first-category power range.

[0077] The control unit 50 monitors the connection status of the connection part 61 to the power supply circuit 60. Specifically, the control unit 50 monitors whether the AC adapter is connected to the power supply circuit 60. The control unit 50 monitors whether the battery is connected to the power supply circuit 60. The control unit 50 monitors whether the USB device is connected to the power supply circuit 60. In addition, the control unit 50 can also monitor the charge level of the battery connected to the power supply circuit 60.

[0078] The control unit 50 determines which power supply source is connected to the connection part 61 based on the connection status of the connection part 61 to the power supply circuit 60. The control unit 50 instructs the power supply circuit 60 to use the determined power supply source. The power supply circuit 60 supplies power to the various components of the image reading device 11 based on the power supply from the power supply source instructed by the control unit 50.

[0079] In particular, the control unit 50 determines the power supply source according to a predetermined priority order for the connection status. Specifically, the control unit 50 determines the power supply source in the following order of priority: AC adapter, high-power USB device, battery, medium-power USB device, and low-power USB device.

[0080] To give a specific example, when the AC adapter is connected to the power supply circuit 60, the control unit 50 determines that the AC adapter is the power source. More specifically, when the AC adapter is connected to a high-power USB device, the control unit 50 uses the AC adapter as the power source. When the AC adapter is connected to a medium-power USB device, the control unit 50 uses the AC adapter as the power source. When the AC adapter is connected to a low-power USB device, the control unit 50 uses the AC adapter as the power source. When the AC adapter is connected to a battery, the control unit 50 uses the AC adapter as the power source.

[0081] When the AC adapter is not connected to the power supply circuit 60, but the high-power supply USB device is connected to the power supply circuit 60, the control unit 50 uses the high-power supply USB device as the power source. When the AC adapter is not connected to the power supply circuit 60, but the medium-power supply USB device is connected to the power supply circuit 60, the control unit 50 uses the medium-power supply USB device as the power source. When the AC adapter is not connected to the power supply circuit 60, but the low-power supply USB device is connected to the power supply circuit 60, the control unit 50 uses the low-power supply USB device as the power source.

[0082] The control unit 50 determines the high-power USB device as the power source if the AC adapter is not connected to the power supply circuit 60, and the high-power USB device and the battery are connected to the power supply circuit 60. The control unit 50 determines the battery as the power source if the AC adapter is not connected to the power supply circuit 60, and the medium-power USB device and the battery are connected to the power supply circuit 60. The control unit 50 determines the battery as the power source if the AC adapter is not connected to the power supply circuit 60, and the low-power USB device and the battery are connected to the power supply circuit 60.

[0083] Furthermore, the control unit 50 does not need to issue an instruction to change the power supply source if the power range of the power supply source changes to an increased level while reading an image based on a read instruction. The control unit 50 can issue an instruction to change the power supply source if the power range of the power supply source changes to a decreased level while reading an image based on a read instruction. The control unit 50 can issue an instruction to change the power supply source if the power range of the power supply source does not change while reading an image based on a read instruction. The control unit 50 can issue an instruction to change the power supply source based on the connection status with the AC adapter, battery, and USB device when not reading an image based on a read instruction.

[0084] During image reading based on a reading instruction, when images are read from multiple documents D based on a single reading instruction, this refers to the period from the start of reading the image from the first document D to the completion of reading the images from all documents D. Therefore, during image reading based on a reading instruction, the control period based on the reading instruction includes a reading period in which the reading unit 40 is actually reading the image and a non-reading period in which the reading unit 40 is not actually reading the image.

[0085] To give a specific example, if the connection state changes from one where an AC adapter and a high-power USB device are connected to one where the AC adapter is not connected, the power range of the power supply source does not change. Similarly, if the connection state changes from one where a battery and a medium-power USB device are connected to one where the battery is not connected, the power range of the power supply source does not change.

[0086] When the connection state changes from one where the AC adapter is connected to a medium-power USB device to one where the AC adapter is not connected, the power range of the power supply source changes to decrease. When the connection state changes from one where the AC adapter is connected to a battery to one where the AC adapter is not connected, the power range of the power supply source changes to decrease. When the connection state changes from one where the AC adapter is connected to a low-power USB device to one where the AC adapter is not connected, the power range of the power supply source changes to decrease.

[0087] When a USB device with moderate power supply is connected, the power range of the power supply changes to increase when an AC adapter is connected. Similarly, when a USB device with low power supply is connected, the power range of the power supply changes to increase when an AC adapter is connected.

[0088] The control unit 50 can be controlled to one of several modes based on the specified power supply source. In other words, the control unit 50 can be controlled to one of several modes based on the connection status with the AC adapter, battery, and USB device.

[0089] The multiple modes are modes that have different power consumption as an image reading device 11. The multiple modes include a low-power mode, a medium-power mode, and a high-power mode. The medium-power mode is a mode that consumes less power than the high-power mode. The low-power mode is a mode that consumes less power than the medium-power mode.

[0090] The high-power mode is controllable when either an AC adapter or a high-power USB device is the power source. The medium-power mode is controllable when either a battery or a medium-power USB device is the power source. The low-power mode is controllable when a low-power USB device is the power source.

[0091] In other words, the high-power mode is a controllable mode when a high-power USB device is connected to the power supply circuit 60. The high-power mode is a controllable mode when an AC adapter is connected to the power supply circuit 60. The medium-power mode is a controllable mode when a medium-power USB device is connected to the power supply circuit 60. The medium-power mode is a controllable mode when a battery is connected to the power supply circuit 60. The low-power mode is a controllable mode when a low-power USB device is connected to the power supply circuit 60. The low-power mode corresponds to an example of the third mode. The high-power mode corresponds to an example of the second mode. The medium-power mode corresponds to an example of the first mode.

[0092] Specifically, the control unit 50 controls the AC adapter to high-output mode when the AC adapter and the high-power USB device are connected to the power supply circuit 60. The control unit 50 controls the AC adapter to high-output mode when the AC adapter and the medium-power USB device are connected to the power supply circuit 60. The control unit 50 controls the AC adapter to high-output mode when the AC adapter and the low-power USB device are connected to the power supply circuit 60.

[0093] The control unit 50 controls the device to high output mode when the AC adapter is not connected to the power supply circuit 60, but a high-power USB device is connected to the power supply circuit 60. The control unit 50 controls the device to medium output mode when the AC adapter is not connected to the power supply circuit 60, but a medium-power USB device is connected to the power supply circuit 60. The control unit 50 controls the device to low output mode when the AC adapter is not connected to the power supply circuit 60, but a low-power USB device is connected to the power supply circuit 60.

[0094] The control unit 50 controls the device to high output mode when the AC adapter is not connected to the power supply circuit 60, and the high-power USB device and battery are connected to the power supply circuit 60. The control unit 50 controls the device to medium output mode when the AC adapter is not connected to the power supply circuit 60, and the medium-power USB device and battery are connected to the power supply circuit 60. The control unit 50 controls the device to medium output mode when the AC adapter is not connected to the power supply circuit 60, and the low-power USB device and battery are connected to the power supply circuit 60.

[0095] <Mode control details> Now, with reference to Figures 4 to 6, the control details for each mode will be explained. As shown in Figure 4, the control content corresponds to each of the multiple types of modes. Control is performed according to the control content corresponding to the mode that is set among the multiple types of modes. In Figure 4, "○" indicates valid information and "×" indicates invalid information.

[0096] For details, the control contents corresponding to each of the multiple modes include the control contents of the control unit 50, the reading speed, and the reading control clock. The control contents corresponding to each of the multiple modes include the document type, carrier sheet, double feed detection, document protection, posture drive, and tray drive. The control contents corresponding to each of the multiple modes include the communication method, LCD display, touch panel, USB memory, and sensor time-division control.

[0097] The control of the control unit 50 ensures that power consumption is lower in medium output mode than in high output mode. The control of the control unit 50 ensures that power consumption is lower in low output mode than in medium output mode.

[0098] In particular, the control of the control unit 50 includes adjusting the operating frequency of the control unit 50. To give a specific example, the operating frequency of the control unit 50 is set to be lower in medium output mode than in high output mode. The operating frequency of the control unit 50 is set to be lower in low output mode than in medium output mode.

[0099] The control content of the control unit 50 includes whether to enable or disable the functions of the control unit 50. In medium output mode, the functions of the control unit 50 are disabled more than in high output mode. In low output mode, the functions of the control unit 50 are disabled more than in medium output mode.

[0100] More specifically, the functions of the control unit 50 include, if the control unit 50 is equipped with multiple CPUs, the functions of at least one of the multiple CPUs. The functions of the control unit 50 include the functions of the GPU related to image processing. The functions of the control unit 50 include functions for controlling storage media such as flash memory. The functions of the control unit 50 include functions for image processing of images read by the reading unit 40. The functions of the control unit 50 include functions for communication using infrared light or the like.

[0101] In high-power mode, images can be read at 40 ppm, 30 ppm, and 5 ppm. In medium-power mode, images cannot be read at 40 ppm, but can be read at 30 ppm and 5 ppm. In low-power mode, images cannot be read at 40 ppm and 30 ppm, but can be read at 5 ppm. Lower reading speeds result in lower power consumption.

[0102] Thus, in high-output mode, the control unit 50 can cause the reading unit 40 to read images at 40 ppm. In high-output mode, the control unit 50 can cause the reading unit 40 to read images at 30 ppm. In high-output mode, the control unit 50 can cause the reading unit 40 to read images at 5 ppm.

[0103] The control unit 50 can prevent the reading unit 40 from reading images at 40 ppm in medium output mode. The control unit 50 can allow the reading unit 40 to read images at 30 ppm in medium output mode. The control unit 50 can allow the reading unit 40 to read images at 5 ppm in medium output mode.

[0104] The control unit 50 prevents the reading unit 40 from reading images at 40 ppm in low-power mode. The control unit 50 prevents the reading unit 40 from reading images at 30 ppm in low-power mode. The control unit 50 can allow the reading unit 40 to read images at 5 ppm in low-power mode.

[0105] The read control clock has a lower period in medium and low output modes than in high output mode. The read control clock is the clock that specifies the control period of the read unit 40. More specifically, the read control clock is the clock that specifies the control period for the timing generator 55 and the analog front end 56. A lower read control clock reduces power consumption.

[0106] In high-output mode, the control unit 50 outputs a read control clock with a normal period to the timing generator 55 and the analog front end 56. In medium-output mode and low-output mode, the control unit 50 outputs a read control clock with a period lower than the normal period to the timing generator 55 and the analog front end 56.

[0107] The document types include thin paper documents D and thick paper documents D. Thick paper documents D require more transport force from the transport unit 21 than thin paper documents D. Therefore, thick paper documents D place a greater control load on the transport unit 21 and consume more power than thin paper documents D.

[0108] In terms of document types, in high-power mode, images can be read from both thin-paper documents D and thick-paper documents D. In medium-power and low-power modes, images can be read from thin-paper documents D, but not from thick-paper documents D.

[0109] In high-output mode, the control unit 50 causes the transport unit 21 to transport the document D and the reading unit 40 to read an image from the document D, regardless of the type of document D. In medium-output mode and low-output mode, when the control unit 50 identifies the transport of a thin-paper document D based on the detection signal from the document thickness sensor 33, it causes the transport unit 21 to transport the thin-paper document D and the reading unit 40 to read an image from the thin-paper document D. In medium-output mode and low-output mode, when the control unit 50 identifies the transport of a thick-paper document D based on the detection signal from the document thickness sensor 33, it stops the transport of the thick-paper document D and the reading of an image from the thick-paper document D.

[0110] In the carrier sheet mode, carrier sheet transport and the carrier sheet sensor 34 are enabled in high-output and medium-output modes, while carrier sheet transport and the carrier sheet sensor 34 are disabled in low-output mode. The carrier sheet requires more transport force from the transport unit 21 than the thin paper original D. Therefore, the control load on the transport unit 21 is greater for the carrier sheet than for the thin paper original D, resulting in higher power consumption. Power consumption is reduced by disabling the carrier sheet sensor 34.

[0111] In high-output and medium-output modes, the control unit 50, based on the detection signal from the document thickness sensor 33, determines when to transport the carrier sheet and causes the transport unit 21 to transport the carrier sheet and the reading unit 40 to read an image from the carrier sheet. In high-output and medium-output modes, the control unit 50 enables and controls the carrier sheet sensor 34. In low-output mode, the control unit 50, based on the detection signal from the document thickness sensor 33, determines when to transport the carrier sheet and causes the transport of the carrier sheet to stop. In low-output mode, the control unit 50 disables the carrier sheet sensor 34. In other words, in low-output mode, the control unit 50 does not allow the transport unit 21 to transport the carrier sheet, but in high-output and medium-output modes, it can allow the transport unit 21 to transport the carrier sheet.

[0112] For double-feed detection, the double-feed sensor 35 is enabled in high-power mode, and disabled in medium-power mode and low-power mode. The control unit 50 controls the double feed sensor 35 by enabling it in high-power mode. The control unit 50 controls the double feed sensor 35 by disabling it in medium-power mode and low-power mode.

[0113] For document protection, the document protection sensor 32 is enabled in high output mode and medium output mode, and disabled in low output mode. Disabling the document protection sensor 32 reduces power consumption.

[0114] The control unit 50 enables and controls the document protection sensor 32 in high-output mode and medium-output mode. The control unit 50 disables and controls the document protection sensor 32 in low-output mode.

[0115] Attitude drive is the operation of an attitude drive motor 49 to change the attitude of the housing 12. In attitude drive mode, the attitude drive motor 49 is activated in high-power mode and medium-power mode, and deactivated in low-power mode. Deactivating the attitude drive motor 49 reduces power consumption.

[0116] The control unit 50 does not drive the attitude drive motor 49 in low-power mode. The control unit 50 can drive the attitude drive motor 49 in high-power mode and medium-power mode.

[0117] The tray drive includes driving the paper feed tray motor 47 and the paper output tray motor 48. In high-power mode, the tray drive is enabled, and in medium-power mode and low-power mode, the tray drive is disabled. Disabling the tray drive reduces power consumption.

[0118] The control unit 50 does not drive the paper feed tray motor 47 in medium output mode and low output mode. The control unit 50 can drive the paper feed tray motor 47 in high output mode.

[0119] The control unit 50 does not drive the paper output tray motor 48 in medium output mode and low output mode. The control unit 50 can drive the paper output tray motor 48 in high output mode.

[0120] The communication methods include first wireless communication, second wireless communication, and wired communication. In wired communication, image data output via wired communication is enabled in high-power mode, medium-power mode, and low-power mode.

[0121] In the first wireless communication mode, the output of image data via the first wireless communication is enabled in high-power mode. In the first wireless communication mode, the output of image data via the first wireless communication is disabled in low-power mode. In the first wireless communication mode, the output of image data via the first wireless communication is disabled while reading an image based on a read instruction, but it is enabled when not reading an image based on a read instruction. Disabling the first wireless communication reduces power consumption. In particular, disabling the first wireless communication while reading an image based on a read instruction reduces power consumption.

[0122] In the second wireless communication mode, image data output via the second wireless communication is enabled in high-power and medium-power modes. In the second wireless communication mode, image data output via the second wireless communication is disabled while reading an image based on a read instruction, but it is enabled when not reading an image based on a read instruction. Disabling the second wireless communication reduces power consumption. In particular, disabling the second wireless communication while reading an image based on a read instruction reduces power consumption.

[0123] The control unit 50 enables and controls the output of image data via wired communication when a wired communication connection is available in high-power mode, medium-power mode, and low-power mode. This allows the control unit 50 to output image data via wired communication in high-power mode, medium-power mode, and low-power mode.

[0124] In high-power mode, the control unit 50 enables and controls the output of image data via the first wireless communication when a connection state is available for the first wireless communication. This allows the control unit 50 to output image data via the first wireless communication in high-power mode.

[0125] In this embodiment, the control unit 50 performs a polling process for the first wireless communication at predetermined intervals. By performing the polling process for the first wireless communication, the control unit 50 can determine whether or not a connection state is in which the first wireless communication is possible with an external device. In other words, the control unit 50 can perform a polling process to recognize the first wireless communication as being in a valid connection state.

[0126] The control unit 50 enables and controls the output of image data via the second wireless communication when a connection state is available for the second wireless communication in high-power mode and medium-power mode. As a result, the control unit 50 can output image data via the second wireless communication in high-power mode and medium-power mode.

[0127] In this embodiment, the control unit 50 performs polling of the second wireless communication at predetermined intervals. By performing polling of the second wireless communication, the control unit 50 can determine whether or not a connection state is in which the second wireless communication is possible with an external device. In other words, the control unit 50 can perform polling to recognize the second wireless communication as being in a valid connection state.

[0128] The control unit 50, in medium output mode, controls the output of image data via the first wireless communication when a connection state is available for the first wireless communication and the unit is not reading an image based on a read instruction. This allows the control unit 50 to output image data via the first wireless communication when an image based on a read instruction is not being read in medium output mode. The control unit 50, in medium output mode, controls the output of image data via the first wireless communication when an image based on a read instruction is being read, and the unit is in a connection state that allows for the first wireless communication. This prevents the control unit 50 from outputting image data via the first wireless communication when an image based on a read instruction is being read in medium output mode.

[0129] In low-power mode, when the connection state allows for second wireless communication, the control unit 50 enables the output of image data via second wireless communication when it is not reading an image based on a read instruction. This allows the control unit 50 to output image data via second wireless communication when it is not reading an image based on a read instruction in low-power mode. In low-power mode, when the connection state allows for second wireless communication, the control unit 50 disables the output of image data via second wireless communication while it is reading an image based on a read instruction. This prevents the control unit 50 from outputting image data via second wireless communication while it is reading an image based on a read instruction in medium-power mode.

[0130] In low-power mode, the control unit 50 disables the output of image data via the first wireless communication when a connection state is available for the first wireless communication. This prevents the control unit 50 from outputting image data via the first wireless communication in low-power mode.

[0131] Furthermore, when multiple types of communication methods are available, the control unit 50 determines the communication method according to a predetermined priority order. Specifically, the control unit 50 determines the communication method in the order of priority of wired communication, second wireless communication, and first wireless communication.

[0132] More specifically, the control unit 50 determines the second wireless communication as the communication method when wired communication is not enabled and the first wireless communication and the second wireless communication are enabled. Furthermore, the control unit 50 determines the wired communication as the communication method when the second wireless communication is not enabled and both wired communication and the first wireless communication are enabled. Finally, the control unit 50 determines the wired communication as the communication method when wired communication, the first wireless communication, and the second wireless communication are all enabled.

[0133] To give a specific example, in high-power mode, when the first wireless communication, the second wireless communication, and wired communication are all in an active connection state, the control unit 50 outputs image data via wired communication, prioritizing it over the first wireless communication and the second wireless communication.

[0134] In other words, the control unit 50 can perform reading processing, first wireless output processing, second wireless output processing, and wired output processing. Reading processing is the process of transporting the document D by the transport unit 21 and reading an image from the document D by the reading unit 40. First wireless output processing is the process of outputting image data to an external device via first wireless communication. Second wireless output processing is the process of outputting image data to an external device via second wireless communication. Wired output processing is the process of outputting image data to an external device via wired communication.

[0135] More specifically, in high-power mode, the control unit 50 can execute the first wireless output process, the second wireless output process, and the wired output process either before or after the completion of the reading process. In particular, in high-power mode, if the first wireless communication, the second wireless communication, and the wired communication are all in an active connection state, the control unit 50 can execute the wired output process with priority over the first wireless output process and the second wireless output process. Furthermore, in high-power mode, if the first wireless communication and the second wireless communication are both in an active connection state, the control unit 50 can execute the second wireless output process with priority over the first wireless output process.

[0136] In medium output mode, the control unit 50 can execute the second wireless output process and the wired output process either before the end of the reading process or after the end of the reading process. On the other hand, in medium output mode, the control unit 50 can execute the first wireless output process after the end of the reading process, without executing the first wireless output process while the reading process is in progress and before the end of the reading process.

[0137] In low-power mode, the control unit 50 can execute wired output processing without executing the first wireless output processing, either before the end of the reading process or after the end of the reading process. On the other hand, in low-power mode, the control unit 50 can execute the second wireless output processing after the end of the reading process, without executing the second wireless output processing while the reading process is in progress but before the end of the reading process.

[0138] In terms of liquid crystal display, the liquid crystal display unit 30 is enabled in high-output mode and medium-output mode, and disabled in low-output mode. Disabling the liquid crystal display unit 30 reduces power consumption.

[0139] The control unit 50 enables and controls the liquid crystal display unit 30 in high-output mode and medium-output mode. This allows the control unit 50 to display an image on the liquid crystal display unit 30 in high-output mode and medium-output mode. The control unit 50 disables and controls the liquid crystal display unit 30 in low-output mode. This prevents the control unit 50 from displaying an image on the liquid crystal display unit 30 in low-output mode.

[0140] In high-power and medium-power modes, the touch panel 29 is enabled, while in low-power mode, the touch panel 29 is disabled. Disabling the touch panel 29 reduces power consumption.

[0141] The control unit 50 enables the touch panel 29 in high-output mode and medium-output mode. This allows the control unit 50 to receive signals from the touch panel 29 in high-output mode and medium-output mode. The control unit 50 disables the touch panel 29 in low-output mode. This prevents the control unit 50 from receiving signals from the touch panel 29 in low-output mode.

[0142] The USB memory indicates whether to enable or disable the storage of image data to the USB memory when the USB memory is connected via the USB connection part 64. In the high-output mode, the storage of image data to the USB memory is enabled, while in the medium-output mode and low-output mode, the storage of image data to the USB memory is disabled. Disabling the storage of image data to the USB memory reduces power consumption. In this embodiment, storing image data to the USB memory consumes more power than outputting image data via wired communication.

[0143] The control unit 50 enables the storage of image data to the USB memory in high-power mode. This allows the control unit 50 to store image data in the USB memory in high-power mode. The control unit 50 disables the storage of image data to the USB memory in medium-power mode and low-power mode. This prevents the control unit 50 from storing image data in the USB memory in medium-power mode and low-power mode.

[0144] In terms of time-division control of the sensor, it is disabled in high-power mode and enabled in medium-power and low-power modes. Time-division control is a control method that switches between an enabled period when the sensor is active and an disabled period when the sensor is disabled.

[0145] In high-power mode, the control unit 50 does not perform time-division control for sensors that are enabled and controlled. In medium-power mode and low-power mode, the control unit 50 can perform time-division control for sensors that are enabled and controlled.

[0146] <Sensor time-division control> Here, we will explain sensor time-division control with reference to Figure 5. Figure 5 shows a specific example in which time-division control is performed for the first sensor, the second sensor, and the third sensor.

[0147] As shown in Figure 5, at the timing indicated by symbol T11, the first sensor becomes active, and the second and third sensors become inactive. After time t1 has elapsed from the timing indicated by symbol T11, at the timing indicated by symbol T12, the second sensor becomes active, and the first and third sensors become inactive. Time t1 is the control period for which the sensors are active divided by the number of sensors. After time t1 has elapsed from the timing indicated by symbol T12, at the timing indicated by symbol T13, the third sensor becomes active, and the first and second sensors become inactive.

[0148] When time t1 has elapsed from the timing indicated by code T13, at the timing indicated by code T21, the first sensor becomes active and the second and third sensors become inactive. When time t1 has elapsed from the timing indicated by code T21, at the timing indicated by code T22, the second sensor becomes active and the first and third sensors become inactive. When time t1 has elapsed from the timing indicated by code T22, at the timing indicated by code T23, the third sensor becomes active and the first and second sensors become inactive.

[0149] By repeatedly performing this control, the system switches between periods when the sensor is enabled and periods when it is disabled, dividing the time during the control cycle in which the sensor is enabled. This time-division control of the sensor reduces power consumption. In addition, the timing of when each sensor is enabled is adjusted so that the periods in which each sensor is enabled do not overlap. This time-division control of the sensor also reduces instantaneous power consumption.

[0150] <Reading and outputting processes> Next, the reading process and output process will be explained with reference to Figure 6. In particular, the reading process and the first wireless output process in the high-power mode and medium-power mode will be mainly explained.

[0151] As shown in Figure 6, in high-output mode, the control unit 50 performs a reading process to read images from two documents D at 40 ppm based on a reading instruction. In this case, the control unit 50 starts the reading process to read the image from the first document D at the timing indicated by code T31. The control unit 50 ends the reading process to read the image from the first document D at the timing indicated by code T32.

[0152] The control unit 50 starts the reading process to read an image from the second document D at the timing indicated by the code T33. The control unit 50 ends the reading process to read an image from the second document D at the timing indicated by the code T34.

[0153] On the other hand, at the timing indicated by reference numeral T41, when the control unit 50 is ready to output image data of the first document D, it starts a first wireless output process to output image data of the first document D, even after starting the reading process to read an image from the second document D. At the timing indicated by reference numeral T42, the control unit 50 ends the first wireless output process to output image data of the first document D.

[0154] At the timing indicated by reference numeral T43, the control unit 50, when it is ready to output image data of the second document D, starts a first wireless output process to output image data of the second document D, even after the reading process for reading images from the second document D has finished. At the timing indicated by reference numeral T44, the control unit 50 terminates the first wireless output process for outputting image data of the second document D.

[0155] Thus, in high-output mode, when the control unit 50 reads images from multiple documents D based on a reading instruction input, it can execute the first wireless output process either before or after the reading process of reading images from multiple documents D is completed. In other words, in high-output mode, the control unit 50 can execute the first wireless output process either before or after the reading process is completed.

[0156] Next, in medium output mode, the control unit 50 performs a reading process to read images from two original documents D at 30 ppm based on the reading instruction. In this case, the control unit 50 starts the reading process to read the image from the first original document D at the timing indicated by reference numeral T51. The control unit 50 ends the reading process to read the image from the first original document D at the timing indicated by reference numeral T52.

[0157] The control unit 50 starts the reading process to read an image from the second document D at the timing indicated by reference numeral T53. The control unit 50 ends the reading process to read an image from the second document D at the timing indicated by reference numeral T54.

[0158] On the other hand, at the timing indicated by reference numeral T61, the control unit 50 determines whether the reading process for reading the image from the second document D has not yet been completed when the image data of the first document D is ready to be output. If the control unit 50 determines that the reading process for reading the image from the second document D has not yet been completed, it does not start the first wireless output process for outputting the image data of the first document D, but instead keeps the execution of the first wireless output process on hold.

[0159] When the control unit 50 determines at the timing indicated by code T62 that the reading process for reading an image from the second document D has finished, it starts a first wireless output process to output image data of the first document D. When the control unit 50 determines at the timing indicated by code T63 that the first wireless output process for outputting image data of the first document D has finished, it starts a first wireless output process to output image data of the first document D.

[0160] At the timing indicated by symbol T64, the control unit 50 starts a first wireless output process to output image data of the second document D, provided that it is ready to output image data of the second document D and the reading process for reading images from the second document D has been completed. At the timing indicated by symbol T65, the control unit 50 terminates the first wireless output process for outputting image data of the second document D.

[0161] Thus, in medium output mode, when the control unit 50 reads images from multiple documents D based on a reading instruction input, it does not execute the first wireless output process before the completion of the reading process that reads images from multiple documents D. Furthermore, in medium output mode, the control unit 50 can execute the first wireless output process after the completion of the reading process that reads images from multiple documents D. In other words, in medium output mode, the control unit 50 can execute the first wireless output process after the completion of the reading process, without executing it before the completion of the reading process.

[0162] Similarly, in low-power mode, when the control unit 50 reads images from multiple documents D based on a reading instruction input, it does not execute the second wireless output process before the completion of the reading process for reading images from multiple documents D. Furthermore, in low-power mode, the control unit 50 can execute the second wireless output process after the completion of the reading process for reading images from multiple documents D. In other words, in low-power mode, the control unit 50 can execute the second wireless output process after the completion of the reading process without executing it before the completion of the reading process. To put it another way, in low-power mode, the control unit 50 does not execute the first wireless output process, but can execute the second wireless output process.

[0163] <Startup mode setting process> Now, with reference to Figure 7, the startup mode setting process will be explained. The startup mode setting process is called when the image reading device 11 is started up, after the initial setup process is completed.

[0164] As shown in Figure 7, in step S11, the control unit 50 performs an AC adapter identification process. In this process, the control unit 50 determines whether or not an AC adapter is connected to the power supply circuit 60. If this process is completed, the control unit 50 proceeds to step S12.

[0165] In step S12, the control unit 50 determines whether or not an AC adapter is connected. If the control unit 50 determines that an AC adapter is connected, it proceeds to step S20. If the control unit 50 determines that an AC adapter is not connected, it proceeds to step S13.

[0166] In step S13, the control unit 50 performs a battery identification process. In this process, as will be described in detail later, the control unit 50 determines whether or not a battery is connected to the power supply circuit 60. In particular, the control unit 50 determines that a battery is connected to the power supply circuit 60 when the battery is physically connected to the power supply circuit 60 and the battery is effectively connected to the power supply circuit 60. Thereafter, the control unit 50 may simply indicate that a battery is connected to the power supply circuit 60 when the battery is physically connected to the power supply circuit 60 and the battery is effectively connected to the power supply circuit 60. When this process is completed, the control unit 50 moves on to step S14.

[0167] In step S14, the control unit 50 determines whether or not the battery is connected. If the control unit 50 determines that the battery is connected, it proceeds to step S21. If the control unit 50 determines that the battery is not connected, it proceeds to step S15.

[0168] In step S15, the control unit 50 performs USB identification processing. In this processing, the control unit 50 determines whether a USB device is connected to the power supply circuit 60 and the USB standard. In particular, the control unit 50 performs enumeration with the USB device in a separate process from the startup mode setting processing, triggered by power-on. The control unit 50 performs enumeration with the USB device in a separate process from the startup mode setting processing, triggered by a change in the connection state with the USB device. In this processing, the control unit 50 determines the connection state with the USB device based on the result of the enumeration. As a result, the control unit 50 determines whether a USB device is connected and the USB standard. When this processing is completed, the control unit 50 proceeds to step S16.

[0169] In step S16, the control unit 50 determines whether or not a high-power USB device is connected. If the control unit 50 determines that a high-power USB device is connected, it proceeds to step S20. If the control unit 50 determines that a high-power USB device is not connected, it proceeds to step S17.

[0170] In step S17, the control unit 50 determines whether or not a medium-power USB device is connected. If the control unit 50 determines that a medium-power USB device is connected, it proceeds to step S21. If the control unit 50 determines that a medium-power USB device is not connected, it proceeds to step S18.

[0171] In step S18, the control unit 50 determines whether a low-power USB device is connected. If the control unit 50 determines that a low-power USB device is connected, it proceeds to step S22. If the control unit 50 determines that a low-power USB device is not connected, it proceeds to step S19. In step S19, the control unit 50 performs a shutdown.

[0172] In step S20, the control unit 50 executes a high-power mode setting process to set the high-power mode as information indicating the mode. When this process is completed, the control unit 50 terminates the startup mode setting process.

[0173] In step S21, the control unit 50 executes a medium output mode setting process to set the medium output mode as information indicating the mode. When this process is completed, the control unit 50 terminates the startup mode setting process.

[0174] In step S22, the control unit 50 executes a low-output mode setting process to set the low-output mode as information indicating the mode. When this process is completed, the control unit 50 terminates the startup mode setting process.

[0175] <Battery identification processing> Next, the battery identification process will be explained with reference to Figure 8. The battery identification process is called in step S13 of the startup mode setting process in Figure 7, step S43 of the normal mode setting process in Figure 9, and step S61 of the charge control process in Figure 11.

[0176] As shown in Figure 8, in step S31, the control unit 50 determines whether or not the battery is physically connected to the power supply circuit 60. If the control unit 50 determines that the battery is physically connected, it proceeds to step S33. If the control unit 50 determines that the battery is not physically connected, it proceeds to step S32.

[0177] In step S32, the control unit 50 executes a battery disconnection setting process to disconnect the battery. Once this process is completed, the control unit 50 terminates the battery identification process. In this way, the control unit 50 disconnects the battery when the battery is not physically connected.

[0178] In step S33, the control unit 50 determines whether the battery is set as an active connection. As will be described in detail later, the control unit 50 determines that the connection state allows power supply from the battery when the conditions regarding the battery's charge level are met, and sets the battery as an active connection. The control unit 50 may also set the battery as an inactive connection during the initial setup process if the battery is physically connected at startup. The control unit 50 may also set the battery as an inactive connection when the battery goes from being physically disconnected to being physically connected. If the control unit 50 determines that the battery is set as an active connection, it proceeds to step S34. If the control unit 50 determines that the battery is not set as an active connection, it proceeds to step S36.

[0179] In step S34, the control unit 50 determines whether the battery charge level is below a minimum. The minimum charge level is the threshold at which power is not supplied from the battery. The minimum charge level may be, for example, 20% of the full charge level, but is not limited to this. If the control unit 50 determines that the battery charge level is below the minimum charge level, it proceeds to step S35. If the control unit 50 determines that the battery charge level is not below the minimum charge level, it terminates the battery identification process. In this way, the control unit 50 maintains the enabled state of the battery when the battery is physically connected and the battery is set as an enabled connection, and it determines that the battery charge level is not below the minimum charge level.

[0180] In step S35, the control unit 50 executes a battery disable setting process to set the battery as an inactive connection. Once this process is completed, the control unit 50 terminates the battery identification process. In this way, the control unit 50 sets the battery as an inactive connection when it determines that the battery's charge level is below the lower limit, while the battery is physically connected and the battery is set as an active connection.

[0181] In step S36, the control unit 50 determines whether the battery charge level is below the upper limit. The upper limit is the threshold at which power can be supplied from the battery. The upper limit may be, for example, 80% of the full charge level, but is not limited to this. If the control unit 50 determines that the battery charge level is above the upper limit, it proceeds to step S37. If the control unit 50 determines that the battery charge level is not above the upper limit, it terminates the battery identification process. In this way, when the battery is physically connected and the battery is set as disabled, the control unit 50 determines that the battery charge level is not above the upper limit and continues to disable the battery.

[0182] In step S37, the control unit 50 executes a battery activation setting process to set the battery as an active connection. In this way, the control unit 50 sets the battery as an active connection when it determines that the battery charge level is above the upper limit while the battery is physically connected and the battery is set as an inactive connection. Once this process is completed, the control unit 50 terminates the battery identification process.

[0183] Here is a specific example of control based on the battery charge level. When the battery is physically connected and a medium-power USB device is connected, the control unit 50 controls the system to medium output mode, using the medium-power USB device as the power source instead of the battery, when the battery charge level is below the lower limit. On the other hand, when the battery charge level is above the upper limit, the control unit 50 controls the system to medium output mode, using the battery as the power source.

[0184] Furthermore, when the battery is physically connected and a low-power USB device is connected, the control unit 50 controls the low-power USB device as the power source and switches to low-output mode when the battery charge level is below the lower limit. On the other hand, when the battery charge level is above the upper limit, the control unit 50 controls the battery as the power source and switches to medium-output mode.

[0185] <Normal Mode Setting Process> Next, the normal mode setting process will be explained with reference to Figure 9. The normal mode setting process is a process that is called at predetermined intervals after the image reading device 11 is started up.

[0186] As shown in Figure 9, in step S41, the control unit 50 performs a mode identification process. In this process, the control unit 50 reads information indicating the set mode and identifies the current mode. When this process is completed, the control unit 50 proceeds to step S42.

[0187] In step S42, the control unit 50 performs AC adapter identification processing in the same manner as in step S11 in Figure 7. In this processing, the control unit 50 determines whether or not an AC adapter is connected to the power supply circuit 60. If this processing is completed, the control unit 50 proceeds to step S43.

[0188] In step S43, the control unit 50 performs a battery identification process, similar to step S13 in Figure 7. In this process, the control unit 50 determines whether or not a battery is connected to the power supply circuit 60. Once this process is complete, the control unit 50 proceeds to step S44.

[0189] In step S44, the control unit 50 performs USB identification processing in the same manner as in step S15 in Figure 7. Once this processing is completed, the control unit 50 proceeds to step S45.

[0190] In step S45, the control unit 50 performs a control table reference process. In this process, the control unit 50 refers to the control table TA shown in Figure 10. The control table TA is a table that shows the control contents corresponding to the current mode and connection status. When this process is completed, the control unit 50 proceeds to step S46.

[0191] <Control Table TA> Now, with reference to Figure 10, the control table TA will be explained. As shown in Figure 10, the control table TA is a table relating to the mode and power source. The control table TA is stored in memory. The control table TA is the table corresponding to the current mode and read control. The control table TA is the table corresponding to the connection status, control content, and power source for the current mode and read control. In Figure 10, valid information is indicated by "○", invalid information by "×", and arbitrary information by "-".

[0192] Specifically, the current modes include a high-power mode, a medium-power mode, and a low-power mode. The current read control includes information indicating that an image is being read based on a read instruction, information indicating that an image is not being read based on a read instruction, and information indicating arbitrary.

[0193] The connection status includes the connection status of the AC adapter, battery, high-power USB device, medium-power USB device, and low-power USB device. The control content includes control content related to read control, control content related to system control, and control content related to mode. The control content related to read control includes information indicating the termination of image reading, information indicating the continuation of image reading, and information indicating discretion. The control content related to system control includes shutdown, restart, and continuation. The control content related to mode includes high-power mode, medium-power mode, and low-power mode. The power supply source includes the AC adapter, battery, high-power USB device, medium-power USB device, and low-power USB device.

[0194] To give a specific example, in high-power mode, if either the AC adapter or a high-power USB device is connected, control will continue. As a result, high-power mode will continue to be controlled. In addition, either the AC adapter or the high-power USB device will be the power source.

[0195] In high-power mode, if the AC adapter and high-power USB device are not connected, and at least one of the battery and medium-power USB device is connected, the restart condition is met. In particular, if an image is being read based on a read command, the restart condition is met after the image reading cancellation condition is met. As a result, the device is controlled to medium-power mode after restarting. In addition, either the battery or the medium-power USB device becomes the power source.

[0196] In high-power and medium-power modes, a restart condition is met when the AC adapter, high-power USB device, battery, and medium-power USB device are not connected, but a low-power USB device is connected. In particular, if an image is being read based on a read command, the restart condition is met after the image reading cancellation condition is met. As a result, the device is controlled to low-power mode after the restart. The low-power USB device then becomes the power source.

[0197] In medium output mode, if the AC adapter and high-power USB device are not connected, and at least one of the battery and the medium-power USB device is connected, control will continue. As a result, the medium output mode will continue to be controlled. In addition, either the battery or the medium-power USB device will be the power source.

[0198] In medium and low output modes, the restart condition is met if either the AC adapter or a high-power USB device is connected. In particular, if an image is being read based on a read command, the image reading cancellation condition is not met, and the restart condition is met after the image reading is completed. As a result, the device is controlled to high output mode after restarting. In addition, either the AC adapter or the high-power USB device becomes the power supply source.

[0199] In medium output mode, the restart condition is met when the AC adapter, high-power USB device, battery, and medium-power USB device are not connected, and a low-power USB device is connected. In particular, if an image is being read based on a read command, the restart condition is met after the image reading cancellation condition is met. As a result, the device is controlled to low output mode after the restart. The low-power USB device becomes the power source.

[0200] In low-power mode, if the AC adapter, high-power USB device, battery, and medium-power USB device are not connected, and a low-power USB device is connected, control will continue. As a result, low-power mode will remain in operation. Furthermore, the low-power USB device will continue to be the power source.

[0201] In low-power mode, if the AC adapter and high-power USB device are not connected, and at least one of the battery and medium-power USB device is connected, the restart condition is met. In particular, if an image is being read based on a read command, the image reading cancellation condition is not met, and the restart condition is met after the image reading is completed. As a result, the device is controlled to medium-power mode after the restart. In addition, either the battery or the medium-power USB device becomes the power source.

[0202] In high-power mode, medium-power mode, and low-power mode, the shutdown condition is met if the AC adapter, battery, high-power USB device, medium-power USB device, and low-power USB device are no longer connected.

[0203] <Normal Mode Setting Process> Returning to the explanation of the normal mode setting process in Figure 9, in step S46, the control unit 50 determines whether the shutdown condition has been met based on the result of referencing the control table TA. The shutdown condition is met in all modes when the AC adapter, battery, high-power USB device, medium-power USB device, and low-power USB device are all disconnected. If the control unit 50 has not determined that the shutdown condition has been met, it proceeds to step S48. If the control unit 50 has determined that the shutdown condition has been met, it proceeds to step S47. In step S47, the control unit 50 performs a shutdown. In this case, if the control unit 50 is outputting image data via various communication methods, it may stop outputting image data.

[0204] In step S48, the control unit 50 determines whether the read cancellation condition has been met based on the result of referencing the control table TA. The read cancellation condition is met when the system switches to a mode with low power consumption while reading an image based on a read instruction. Specifically, the read cancellation condition is met when the system switches from high-output mode to medium-output mode or low-output mode while reading an image based on a read instruction. The read cancellation condition is met when the system switches from medium-output mode to low-output mode while reading an image based on a read instruction. If the control unit 50 determines that the read cancellation condition has been met, it proceeds to step S49. If the control unit 50 determines that the read cancellation condition has not been met, it proceeds to step S51.

[0205] In step S49, the control unit 50 executes a read cancellation process. In this process, the control unit 50 controls the reading unit 40 to cancel image reading based on the read instruction. When this process is completed, the control unit 50 proceeds to step S50.

[0206] In step S50, the control unit 50 executes a paper ejection control process. In this process, the control unit 50 controls the transport unit 21 to eject the document D that is being transported. When this process is completed, the control unit 50 proceeds to step S51.

[0207] In step S51, the control unit 50 determines whether the restart condition has been met based on the result of referencing the control table TA. The restart condition is met when a mode transition is required. If the control unit 50 has not determined that the restart condition has been met, it terminates the normal mode setting process. If the control unit 50 has determined that the restart condition has been met, it proceeds to step S52. In step S52, the control unit 50 performs a restart. In this case, if the control unit 50 is outputting image data via various communication methods, it may stop outputting image data.

[0208] Here, we will explain a specific example of power source and mode control. This section describes the case in high-output mode when the connection state changes from one where the AC adapter and the high-power supply USB device are connected to one where the high-power supply USB device is connected but the AC adapter is not. In this case, the control unit 50 uses the high-power supply USB device as the power source and continues control in high-output mode.

[0209] This section describes the case in high-output mode when the connection state changes from one where the AC adapter is connected but no USB device is connected, to one where both the AC adapter and the USB device are connected. In this case, the control unit 50 continues to use the AC adapter as the power supply and continues control in high-output mode.

[0210] This section describes what happens when, in high-output mode, during image reading based on a reading instruction, the connection state changes from one where the AC adapter and battery are connected to one where the AC adapter is connected but the battery is not. In this case, the control unit 50 continues to use the AC adapter as the power supply and continues control in high-output mode.

[0211] This section describes what happens in high-output mode when, during image reading based on a reading instruction, the connection state changes from one where the AC adapter and the medium-power USB device are connected to one where the AC adapter is connected but the medium-power USB device is not. In this case, the control unit 50 continues to use the AC adapter as the power source and continues control in high-output mode.

[0212] This section describes what happens when, in high-output mode, during image reading based on a reading instruction, the connection state changes from one where the AC adapter and a low-power USB device are connected to one where the AC adapter is connected but the low-power USB device is not. In this case, the control unit 50 continues to use the AC adapter as the power source and continues control in high-output mode.

[0213] This section describes what happens in high-output mode when, during image reading at 40 ppm based on a reading instruction, the connection state changes from one where the AC adapter and the low-power USB device are connected to one where the AC adapter is not connected. In this case, the control unit 50 stops reading the image at 40 ppm and restarts. As a result, after restarting, the control unit 50 uses the low-power USB device as the power source and controls the system to low-output mode.

[0214] This section describes what happens in high-output mode when, during image reading at 5 ppm based on a reading instruction, the connection state changes from one where the AC adapter and the low-power USB device are connected to one where the AC adapter is not connected. In this case, the control unit 50 stops image reading at 5 ppm and restarts. As a result, after restarting, the control unit 50 uses the low-power USB device as the power source and controls the system to low-output mode.

[0215] This section describes what happens in low-power mode when, during image reading at 5 ppm based on a reading instruction, the connection state changes from one where the AC adapter is not connected and a low-power USB device is connected to one where the AC adapter is connected. In this case, the control unit 50 continues to use the low-power USB device as the power source and continues control in low-power mode. Then, after the image reading at 5 ppm is completed, the control unit 50 restarts. As a result, after the restart, the control unit 50 uses the AC adapter as the power source and controls the system to high-power mode.

[0216] This section describes what happens when, in high-output mode, during image reading at 40 ppm based on a reading instruction, the connection state changes from one where the AC adapter is not connected and a high-power supply USB device is connected to one where the AC adapter is connected. In this case, the control unit 50 continues to use the high-power supply USB device as the power source and continues control in high-output mode. Then, after the image reading at 40 ppm is completed, the control unit 50 restarts. As a result, after the restart, the control unit 50 uses the AC adapter as the power source and controls the system in high-output mode.

[0217] This section describes what happens when the connection state changes from one where the AC adapter is not connected but the battery is connected, to one where the AC adapter is connected, in medium output mode. In this case, the control unit 50 restarts. As a result, after restarting, the control unit 50 uses the AC adapter as the power supply source and controls the system to high output mode.

[0218] <Charge control processing> Next, the charging control process will be explained with reference to Figure 11. The charging control process is called at predetermined intervals after the image reading device 11 is started up.

[0219] As shown in Figure 11, in step S61, the control unit 50 performs a battery identification process, similar to step S13 in Figure 7. In this process, the control unit 50 determines whether or not a battery is connected to the power supply circuit 60. Once this process is complete, the control unit 50 proceeds to step S62.

[0220] In step S62, the control unit 50 determines whether or not the battery is physically connected to the power supply circuit 60. If the control unit 50 determines that the battery is not physically connected, it terminates the charging control process. If the control unit 50 determines that the battery is physically connected, it proceeds to step S63.

[0221] In step S63, the control unit 50 determines whether the battery is fully charged. If the control unit 50 determines that the battery is fully charged, it terminates the charging control process. If the control unit 50 determines that the battery is not fully charged, it proceeds to step S64.

[0222] In step S64, the control unit 50 performs AC adapter identification processing in the same manner as in step S11 in Figure 7. In this processing, the control unit 50 determines whether or not an AC adapter is connected to the power supply circuit 60. If this processing is completed, the control unit 50 proceeds to step S65.

[0223] In step S65, the control unit 50 performs USB identification processing in the same manner as in step S15 in Figure 7. Once this processing is completed, the control unit 50 proceeds to step S66.

[0224] In step S66, the control unit 50 determines whether or not an AC adapter is connected. If the control unit 50 determines that an AC adapter is connected, it proceeds to step S70. If the control unit 50 determines that an AC adapter is not connected, it proceeds to step S67.

[0225] In step S67, the control unit 50 determines whether or not a USB device is connected. If the control unit 50 determines that no USB device is connected, it terminates the charging control process. If the control unit 50 determines that a USB device is connected, it proceeds to step S68.

[0226] In step S68, the control unit 50 determines whether or not a high-power USB device is connected. If the control unit 50 determines that a high-power USB device is connected, it proceeds to step S70. If the control unit 50 determines that a high-power USB device is not connected, it proceeds to step S69.

[0227] In step S69, the control unit 50 determines whether or not it is currently reading an image based on a read instruction. If the control unit 50 determines that it is currently reading an image based on a read instruction, it terminates the charging control process. If the control unit 50 determines that it is not currently reading an image based on a read instruction, it proceeds to step S70.

[0228] In step S70, the control unit 50 charges the battery. In this process, the control unit 50 charges the battery connected to the power supply circuit 60. When this process is completed, the control unit 50 terminates the charging control process.

[0229] Thus, the control unit 50 can charge the battery when it is not fully charged while the AC adapter is connected and the battery is physically connected. The control unit 50 can charge the battery when it is not fully charged while the high-power USB device is connected and the battery is physically connected. The control unit 50 can charge the battery when it is not fully charged while the USB device other than the high-power USB device is connected and the battery is physically connected, provided that it is not currently reading an image based on a read instruction.

[0230] In other words, in high-output mode, when the battery and the high-power USB device are connected, the control unit 50 can charge the battery using power supplied from the high-power USB device. Also, in medium-output mode and low-output mode, when the battery and the low-power USB device are connected, the control unit 50 will not charge the battery using power supplied from the low-power USB device while reading an image based on a read instruction. In medium-output mode and low-output mode, when the battery and the low-power USB device are connected, the control unit 50 can charge the battery using power supplied from the low-power USB device when it is not reading an image based on a read instruction.

[0231] <Operation of the First Embodiment> The operation of the first embodiment will now be described. The system monitors whether the AC adapter, battery, and USB device are connected to the power supply circuit 60. The charge level of the battery connected to the power supply circuit 60 is also monitored. Based on the connection status of the AC adapter, battery, and USB device to the power supply circuit 60, the power supply source is determined. In particular, the power supply source is determined according to a predetermined priority order for the connection status. Power supply sources with a higher power output have a higher priority. Therefore, power supply sources capable of supplying a higher power output are given priority. This allows for stable control of image reading.

[0232] During image reading based on a read command, the power supply source is not changed even if the power range of the power supply changes. This allows for stable image reading based on the read command.

[0233] The image reading device 11 can be controlled to one of several modes based on the power supply source. In other words, it can be controlled to one of several modes based on the connection status with the AC adapter, battery, and USB device. By controlling to one of several modes in this way, the power consumption of the image reading device 11 can be adjusted. That is, the power consumption of the image reading device 11 can be adjusted to correspond to the power supply source and mode.

[0234] In particular, control is performed according to the control content corresponding to the set mode. This allows the control content, reading speed, and reading control clock of the control unit 50 to be adjusted to correspond to the set mode. Furthermore, the document type, carrier sheet, double feed detection, document protection, posture drive, and tray drive can be adjusted to correspond to the set mode. In addition, the communication method, LCD display, touch panel, USB memory, and sensor time-division control can be adjusted to correspond to the set mode.

[0235] To explain the communication method in detail, in high-power mode, the first wireless output process can be executed either before or after the reading process is completed. On the other hand, in medium-power mode, the first wireless output process is not executed before the reading process is completed, but becomes executable after the reading process is completed. In low-power mode, the second wireless output process is not executed before the reading process is completed, but becomes executable after the reading process is completed. Furthermore, wired output processing has a higher priority than second wireless output processing, and second wireless output processing has a higher priority than first wireless output processing.

[0236] During image reading based on a read command, if the power range of the power supply source does not change due to a change in the connection state, the image reading based on the read command will continue. In this case, the power supply source can be changed while the image reading based on the read command is in progress.

[0237] If, during image reading based on a read command, the power range of the power supply changes to increase due to a change in the connection state, the image reading based on the read command will continue. In this case, the power supply and mode will not be changed during the image reading based on the read command. After the image reading based on the read command is completed, a restart will be performed. Then, after the restart, the power supply and mode will be changed.

[0238] If, during image reading based on a read command, the power range of the power supply source decreases due to a change in the connection status, the image reading based on the read command will be stopped and the device will be restarted. After the restart, the power supply source and mode will be changed.

[0239] Furthermore, if the battery charge level falls below the minimum level, it is determined that the battery is not connected. If the battery charge level rises above the maximum level after falling below the minimum level, it is determined that the battery is not connected. This allows control related to image reading to be performed without letting the battery charge level drop below the minimum level.

[0240] In high-power mode, the battery can be charged when the battery is physically connected and at least one of the AC adapter and / or USB device is connected. On the other hand, in medium-power mode and low-power mode, the battery can be charged when the device is not reading an image based on a reading instruction. In medium-power mode and low-power mode, the battery is not charged while the device is reading an image based on a reading instruction.

[0241] <Effects of the First Embodiment> The effects of the first embodiment will be described. (1) Multiple modes include a low-power mode and a high-power mode. The low-power mode is a controllable mode when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a controllable mode when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The high-power mode is a controllable mode when an AC adapter capable of supplying power values ​​within the high-power range is connected. In the low-power mode, the control unit 50 does not perform image reading at 40 ppm, but can perform image reading at 5 ppm. In the high-power mode, the control unit 50 can perform image reading at 5 ppm and can also perform image reading at 40 ppm. Therefore, even if the power range that can be supplied by USB devices differs, image reading can be performed at 5 ppm in the same way. On the other hand, even with the same USB device, image reading can be performed at 40 ppm depending on the power range that can be supplied by the USB device. Thus, image reading can be performed at a reading speed corresponding to the power supply range available from the USB device. Therefore, image reading functions can be implemented according to power consumption.

[0242] (2) In high-output mode, when the connection state changes from one in which the AC adapter and the high-power USB device are connected to one in which the AC adapter is not connected, the control unit 50 uses the high-power USB device as the power source. In this case, the control unit 50 continues control in high-output mode. Therefore, even if the connection state changes to one in which the AC adapter is not connected, if the high-power USB device is connected, the power source can be changed from the AC adapter to the high-power USB device. In addition, control in high-output mode can be continued. Thus, image reading functions can be implemented according to power consumption.

[0243] (3) In high-output mode, the control unit 50 stops reading an image at 40 ppm based on a read command if the connection state changes from one where the AC adapter and the low-power USB device are connected to one where the AC adapter is not connected. Therefore, if the connection state changes to one where the AC adapter is not connected while reading an image at 40 ppm based on a read command, the image reading can be stopped when the power supply range has decreased. Thus, the image reading function can be implemented according to the power consumption.

[0244] (4) In high-output mode, the control unit 50 stops reading an image at 5 ppm based on a read command if the connection state changes from one where the AC adapter and the low-power USB device are connected to one where the AC adapter is not connected. Therefore, if the connection state changes to one where the AC adapter is not connected while reading an image at 5 ppm based on a read command, the image reading can be stopped when the power supply range has decreased. Thus, the image reading function can be implemented according to the power consumption.

[0245] (5) In low-output mode, when the control unit 50 is reading an image at 5 ppm based on a read instruction and the connection state changes from when a low-power USB device is connected to when an AC adapter is connected, the control unit 50 continues to use the low-power USB device as a power source. In this case, the control unit 50 continues control in low-output mode. After the reading of the image at 5 ppm based on the read instruction is completed, the control unit 50 uses the AC adapter as a power source and controls to high-output mode. Therefore, even if the connection state changes to when an AC adapter is connected during the reading of an image at 5 ppm based on a read instruction, the power supply range does not increase, and the low-power USB device continues to be used as a power source. Control in low-output mode is then continued. As a result, by continuing to use the power source and mode without changing them during the reading of an image at 5 ppm based on a read instruction, stable image reading can be continued. Therefore, the functions related to image reading can be realized according to the power consumption.

[0246] (6) In addition, after the image reading at 5 ppm based on the reading instruction is completed, the power supply range can be increased by using the AC adapter as the power source, and control in high-output mode can be started. Therefore, the image reading function can be implemented according to the power consumption.

[0247] (7) In high-output mode, when the control unit 50 is reading an image at 40 ppm based on a read instruction, and the connection state changes from when a high-power USB device is connected to when an AC adapter is connected, the control unit 50 continues to use the high-power USB device as the power source. In this case, the control unit 50 continues control in high-output mode. After the image reading at 40 ppm is completed, the control unit 50 uses the AC adapter as the power source and continues control in high-output mode. Therefore, even if the connection state changes to when an AC adapter is connected during the image reading at 40 ppm based on a read instruction, if a high-power USB device is connected, the high-power USB device will continue to be used as the power source. And control in high-output mode will continue. As a result, by continuing to use the power source and mode without changing them during the image reading at 40 ppm based on a read instruction, stable image reading can be continued. Therefore, the functions related to image reading can be realized according to the power consumption.

[0248] (8) In addition, after image reading at 40 ppm is completed, the power supply can be changed to the AC adapter by using the AC adapter as the power supply, and control in high-output mode can be continued. Therefore, the image reading function can be implemented according to the power consumption.

[0249] (9) Multiple modes include a medium output mode. The medium output mode is a controllable mode when a medium-power USB device capable of supplying power values ​​within the medium power range, which is higher than the low power range and lower than the high power range, is connected. In the medium output mode, the control unit 50 does not perform image reading at 40 ppm, but can perform image reading at 5 ppm, and can also perform image reading at 30 ppm. For this reason, in addition to the low output mode and high output mode, it is possible to control to the medium output mode. Even with the same USB device, it is possible to have diversity in the power range that can be supplied by the USB device and the reading speed corresponding to the power range that can be supplied. Therefore, the image reading function can be realized according to the power consumption.

[0250] (10) In high-output mode, when the battery and a high-power supply USB device are connected, the control unit 50 can charge the battery by power supplied from the high-power supply USB device. In low-output mode, when the battery and a low-power supply USB device are connected, the control unit 50 does not charge the battery by power supplied from the low-power supply USB device while reading an image based on a read instruction. Therefore, even with the same USB device, whether or not the battery is charged while reading an image based on a read instruction can be made to differ depending on the power range that the USB device can supply. In particular, when a low-power supply USB device with a lower power range that can supply power than a high-power supply USB device is connected, the battery is not charged while reading an image based on a read instruction, so power consumption can be suppressed. Therefore, the image reading function can be implemented according to the power consumption.

[0251] (11) Multiple modes include a medium output mode. The battery can supply power values ​​within the medium power range. The medium output mode is a controllable mode when the battery is connected. In the medium output mode, the control unit 50 does not perform image reading at 40 ppm, but can perform image reading at 5 ppm and can also perform image reading at 30 ppm. Therefore, in addition to the low output mode and high output mode, it is possible to control to the medium output mode. Power can be supplied from the battery, and there can be diversity in the type of power supply and the reading speed according to the power range that can be supplied. Therefore, the image reading function can be realized according to the power consumption.

[0252] (12) When the battery is physically connected and a medium-power USB device is connected, the control unit 50 controls the system to medium output mode by using the medium-power USB device as the power source when the battery charge level is below the lower limit. Therefore, when a medium-power USB device capable of supplying power values ​​within the medium power range is connected and the battery charge level is below the lower limit, the medium-power USB device can be used as the power source instead of the battery. This allows the system to be controlled to medium output mode without reducing the battery charge level. Consequently, image reading functions can be implemented according to power consumption.

[0253] (13) When the battery is physically connected and a medium-power USB device is connected, the control unit 50 controls the system to medium output mode using the battery as a power source when the battery charge level is above the upper limit. Therefore, when a medium-power USB device capable of supplying power values ​​within the medium power range is connected, and the battery charge level is above the upper limit, the battery can be used as a power source. This allows the system to be controlled to medium output mode by effectively utilizing the power supplied from the battery. Consequently, image reading functions can be implemented according to power consumption.

[0254] (14) When the battery is physically connected and a low-power USB device is connected, the control unit 50 controls the low-power USB device as the power source and switches to low-output mode when the battery charge level is below the lower limit. Therefore, when a low-power USB device with a lower power range than the battery is connected and the battery charge level is below the lower limit, the low-power USB device can be used as the power source instead of the battery. This allows the system to be controlled to low-output mode without reducing the battery charge level. Consequently, image reading functions can be implemented according to power consumption.

[0255] (15) When the battery is physically connected and a low-power USB device is connected, the control unit 50 controls the system to medium output mode by using the battery as a power source when the battery charge level is above the upper limit. Therefore, when a low-power USB device with a lower power range than the battery is connected, the battery can be used as a power source when the battery charge level is above the upper limit. This allows the system to be controlled to medium output mode by effectively utilizing the power supplied from the battery, which has a higher power range than the low-power USB device. Consequently, image reading functions can be implemented according to power consumption.

[0256] (16) In medium output mode, when the battery and a medium-power supply USB device are connected, the control unit 50 does not charge the battery by power supplied from the medium-power supply USB device while reading an image based on a read command. Therefore, even with the same USB device, whether or not the battery is charged while reading an image based on a read command can be made to differ depending on the power range that the USB device can supply. In particular, when a medium-power supply USB device with a lower power range that can supply power than a high-power supply USB device is connected, the battery is not charged while reading an image based on a read command, so power consumption can be suppressed. Therefore, the image reading function can be implemented according to the power consumption.

[0257] (17) In medium output mode, when the connection state changes from a battery-connected state to an AC adapter-connected state, the control unit 50 uses the AC adapter as a power source and controls the system to high output mode. Therefore, when the connection state changes to one in which an AC adapter with a higher power range than the battery is connected, the AC adapter can be used as a power source. This allows the system to be controlled to high output mode by effectively utilizing the power supplied from the AC adapter without reducing the battery charge level. Consequently, image reading functions can be implemented according to power consumption.

[0258] (18) In low-power mode, the control unit 50 does not drive the paper feed tray motor 47 that moves the paper feed tray 16, but can drive the paper feed tray motor 47 in high-power mode. Therefore, in low-power mode, which has a lower power range than high-power mode, the paper feed tray motor 47 is not driven, thus reducing power consumption. Consequently, image reading functions can be implemented according to power consumption.

[0259] (19) In low-power mode, the control unit 50 does not drive the paper output tray motor 48 that moves the paper output tray 17, but can drive the paper output tray motor 48 in high-power mode. Therefore, in low-power mode, which has a lower power range than high-power mode, the paper output tray motor 48 is not driven, thus reducing power consumption. Consequently, image reading functions can be implemented according to power consumption.

[0260] (20) In low-power mode, the control unit 50 does not drive the attitude drive motor 49 that drives the housing 12 to change its attitude, but it can drive the attitude drive motor 49 in high-power mode. Therefore, in low-power mode, which has a lower power range than high-power mode, the attitude drive motor 49 is not driven, thus reducing power consumption. Consequently, the image reading function can be implemented according to the power consumption.

[0261] (21) The control unit 50 does not allow the transport unit 21 to transport the carrier sheet in low-power mode, but allows the transport unit 21 to transport the carrier sheet in high-power mode. The control unit 50 disables the carrier sheet sensor 34 in low-power mode, but enables the carrier sheet sensor 34 in high-power mode. Therefore, in low-power mode, which has a lower power range than high-power mode, the control unit 50 does not transport the carrier sheet, which requires more transport force than the original document D, such as thin paper, thus reducing power consumption. Also, in low-power mode, which has a lower power range than high-power mode, the carrier sheet sensor 34 can be disabled, further reducing power consumption. Thus, image reading functions can be implemented according to power consumption.

[0262] (22) The control unit 50 disables the double feed sensor 35 in low-power mode, but enables the double feed sensor 35 in high-power mode. Therefore, the double feed sensor 35 can be disabled in low-power mode, which has a lower power range than high-power mode, thereby reducing power consumption. Consequently, image reading functions can be implemented according to power consumption.

[0263] (23) In low-power mode, the control unit 50 can perform time-division control to switch between an active period in which the sensor is enabled and an inactive period in which the sensor is disabled. Therefore, in low-power mode, which has a lower power range than high-power mode, time-division control can be performed to switch between an inactive period in which the sensor is disabled and an active period in which the sensor is enabled, thereby reducing power consumption. Consequently, image reading functions can be implemented according to power consumption.

[0264] (24) In medium output mode, the control unit 50 can execute the first wireless output process after the completion of the reading process, without executing it before the completion of the reading process. In high output mode, the control unit 50 can execute the first wireless output process either before the completion of the reading process or after the completion of the reading process. For this reason, in medium output mode, where the power supply range is lower than in high output mode, the control unit 50 does not execute the first wireless output process before the completion of the reading process, unlike in high output mode. In this way, the timing of the execution of the reading process and the first wireless output process can be adjusted according to the power supply range. Therefore, the image reading function can be realized according to the power consumption.

[0265] (25) In high-output mode, when both the first wireless communication and wired communication are in an active connection state, the control unit 50 can prioritize wired output processing over the first wireless output processing, as wired output processing consumes less power than the first wireless communication processing. Therefore, image reading functions can be implemented according to power consumption.

[0266] (26) In medium output mode, when the control unit 50 reads images from multiple documents D based on a reading instruction input, it does not execute the first wireless output process before the completion of the reading process for reading images from multiple documents D. The control unit 50 can then execute the first wireless output process after the completion of the reading process for reading images from multiple documents D in medium output mode. Therefore, in medium output mode, where the power supply range is lower than in high output mode, the execution of the reading process and the execution of the first wireless output process can be adjusted so as not to overlap. Thus, the image reading function can be implemented according to the power consumption.

[0267] (27) In addition, the time from the start to the end of the reading process, which involves reading images from multiple original documents D, can be shortened. (28) In the low-power mode, where the power supply range is lower than that of the medium-power mode, the control unit 50 can perform a second wireless output process that consumes less power than the first wireless communication process without performing the first wireless output process. In this way, the type of wireless communication can be adjusted according to the power supply range. Therefore, the image reading function can be implemented according to the power consumption.

[0268] (29) Capacitor 60A has a capacity that can compensate for the power consumption caused by the polling process of the first wireless communication and the second wireless communication. Therefore, using capacitor 60A, which has a capacity that can compensate for the power consumption caused by the polling process, the polling process can be performed to recognize the first wireless communication and the second wireless communication as being in a valid connection state. Thus, the image reading function can be implemented according to the power consumption.

[0269] (30) The control unit 50 performs an enumeration of the connection status with the USB device when either the power is turned on or the connection status with the USB device changes. Based on the results of the enumeration, the control unit 50 determines the connection status with the USB device. Therefore, the connection status with the USB device can be determined when either the power is turned on or the connection status with the USB device changes. Thus, the image reading function can be implemented according to the power consumption.

[0270] (31) The notification unit 28 notifies the controlled mode. This makes it possible for the user to identify the controlled mode. This makes it possible for the user to identify the function related to image reading. Therefore, user convenience can be improved.

[0271] [Second Embodiment] Next, a second embodiment will be described. In the following description, the same reference numerals will be used for components that have already been described in the embodiments, and redundant explanations will be omitted or simplified.

[0272] In the second embodiment, when the control unit 50 reads images from multiple documents D based on a read instruction input in medium output mode, it can perform a first wireless output process after the completion of the reading process for reading images from each of the multiple documents D. In the second embodiment, when the control unit 50 reads images from multiple documents D based on a read instruction input in low output mode, it can perform a second wireless output process after the completion of the reading process for reading images from each of the multiple documents D.

[0273] As shown in Figure 12, in medium output mode, the control unit 50 performs a reading process to read images from two original documents D at 30 ppm based on a reading instruction. In this case, the control unit 50 starts the reading process to read the image from the first original document D at the timing indicated by code T51. The control unit 50 ends the reading process to read the image from the first original document D at the timing indicated by code T52.

[0274] At the timing indicated by reference numeral T53, the control unit 50 determines whether the first wireless output process for outputting image data from the first document D has finished, when it is ready to start the reading process for reading an image from the second document D. The control unit 50 determines that the first wireless output process for outputting image data from the first document D has not yet finished, and does not start the reading process for reading an image from the second document D, instead waiting for the execution of that reading process.

[0275] At the timing indicated by reference numeral T71, when the control unit 50 is ready to output image data from the first document D, it starts a first wireless output process to output image data from the first document D, before starting the reading process to read images from the second document D. At the timing indicated by reference numeral T72, the control unit 50 ends the first wireless output process to output image data from the first document D.

[0276] When the control unit 50 determines that it is after the completion of the first wireless output process for outputting the image data of the first original document D at the timing indicated by the symbol T58, it starts the reading process for reading an image from the second original document D. The control unit 50 ends the reading process for reading an image from the second original document D at the timing indicated by the symbol T59.

[0277] If the control unit 50 is in a state where it can output the image data of the second original document D at the timing indicated by the symbol T73 and after the completion of the reading process for reading an image from the second original document D, it starts the first wireless output process for outputting the image data of the second original document D. The control unit 50 ends the first wireless output process for outputting the image data of the second original document D at the timing indicated by the symbol T74.

[0278] Thus, in the medium output mode, when the control unit 50 causes images to be read from a plurality of original documents D based on an input read instruction, it does not execute the first wireless output process before the completion of the reading process for causing images to be read from each of the plurality of original documents D. And in the medium output mode, the control unit 50 can execute the first wireless output process after the completion of the reading process for causing images to be read from each of the plurality of original documents D and before the start of the reading process for causing an image to be read from the next original document D.

[0279] Similarly, in the low output mode, when the control unit 50 causes images to be read from a plurality of original documents D based on an input read instruction, it does not execute the second wireless output process before the completion of the reading process for causing images to be read from each of the plurality of original documents D. And in the low output mode, the control unit 50 can execute the second wireless output process after the completion of the reading process for causing images to be read from each of the plurality of original documents D and before the start of the reading process for causing an image to be read from the next original document D.

[0280] <Effects of the Second Embodiment> The effects of the second embodiment will be described. (32) In medium output mode, the control unit 50 can execute the first wireless output process after the reading process, which reads images from each of the multiple original documents D, has been completed. In this way, in medium output mode, where the power supply range is lower than in high output mode, the execution of the reading process and the execution of the first wireless output process can be adjusted so as not to overlap. Therefore, the image reading function can be implemented according to the power consumption.

[0281] (33) In addition, the timing of the execution of the first wireless communication that outputs image data of images read from each of the multiple original documents D can be advanced. [Third Embodiment] Next, a third embodiment will be described.

[0282] In the third embodiment, when the control unit 50 reads images from multiple documents D based on a read instruction input in medium output mode, it can execute a first wireless output process after the completion of the reading process in which images are read from a predetermined number of documents D among the multiple documents D. In the third embodiment, when the control unit 50 reads images from multiple documents D based on a read instruction input in low output mode, it can execute a second wireless output process after the completion of the reading process in which images are read from a predetermined number of documents D among the multiple documents D.

[0283] As shown in Figure 13, in medium output mode, the control unit 50 performs a reading process to read images from four or more original documents D at 30 ppm based on a reading instruction. The predetermined number of documents is set to, for example, three. In this case, the control unit 50 starts the reading process to read the image from the first original document D at the timing indicated by reference numeral T51. The control unit 50 ends the reading process to read the image from the first original document D at the timing indicated by reference numeral T52.

[0284] The control unit 50 starts the reading process to read an image from the second document D at the timing indicated by reference numeral T53. The control unit 50 ends the reading process to read an image from the second document D at the timing indicated by reference numeral T54.

[0285] The control unit 50 starts the reading process to read an image from the third document D at the timing indicated by the code T55. The control unit 50 ends the reading process to read an image from the third document D at the timing indicated by the code T56.

[0286] At the timing indicated by reference numeral T61, when the control unit 50 is ready to output the image data of the first document D, it determines whether the reading process for reading the image from the third document D has been completed. If the control unit 50 determines that the reading process for reading the image from the third document D has not yet been completed, it does not start the first wireless output process for outputting the image data of the first document D, but instead waits for the execution of the first wireless output process to begin.

[0287] At the timing indicated by reference numeral T81, the control unit 50 determines whether the reading process for reading the image from the third document D has been completed when it becomes ready to output the image data from the second document D. If the control unit 50 determines that the reading process for reading the image from the third document D has not yet been completed, it does not start the first wireless output process for outputting the image data from the second document D, but instead waits for the execution of the first wireless output process to begin.

[0288] When the control unit 50 determines at the timing indicated by code T82 that the reading process for reading an image from the third document D has been completed, it starts a first wireless output process to output image data of the first document D. At the timing indicated by code T83, the control unit 50 ends the first wireless output process to output image data of the first document D.

[0289] When the control unit 50 determines at the timing indicated by code T84 that the reading process for reading an image from the third document D has finished, it starts a first wireless output process to output image data from the second document D. When the control unit 50 determines at the timing indicated by code T85 that the first wireless output process for outputting image data from the second document D has finished.

[0290] At the timing indicated by reference numeral T86, if the control unit 50 is ready to output image data of the third document D, and the reading process for reading images from the third document D has been completed, it starts a first wireless output process to output image data of the third document D. At the timing indicated by reference numeral T87, the control unit 50 ends the first wireless output process for outputting image data of the third document D.

[0291] At the timing indicated by reference numeral T57, when the control unit 50 is ready to start the reading process for reading an image from the fourth document D, it determines whether the first wireless output process for outputting image data from the third document D has finished. If the control unit 50 determines that the first wireless output process for outputting image data from the third document D has not yet finished, it does not start the reading process for reading an image from the fourth document D and waits for the execution of that reading process to begin.

[0292] When the control unit 50 determines that the first wireless output process for outputting image data of the third document D has finished at the timing indicated by code T60, it starts a reading process to read an image from the fourth document D.

[0293] Furthermore, the control unit 50 executes a first wireless output process to output image data for a predetermined number of original documents D after each reading process that reads images from a predetermined number of original documents D, such as 3, 6, or 9 documents.

[0294] Thus, in medium output mode, when the control unit 50 reads images from multiple documents D based on a reading instruction input, it does not execute the first wireless output process before the completion of the reading process that reads images from a predetermined number of documents D. Then, in medium output mode, the control unit 50 can execute the first wireless output process after the completion of the reading process that reads images from a predetermined number of documents D.

[0295] Similarly, in the low output mode, when the control unit 50 causes an image to be read from a plurality of original documents D based on an input read instruction, the control unit 50 does not execute the second wireless output process before the end of the reading process of reading an image from a predetermined number of original documents D among the plurality of original documents D. Then, the control unit 50 can execute the second wireless output process after the end of the reading process of reading an image from a predetermined number of original documents D among the plurality of original documents D in the low output mode.

[0296] <Effect of the Third Embodiment> (34) In the medium output mode, the control unit 50 can execute the first wireless output process after the reading process of reading an image from a predetermined number of original documents D among the plurality of original documents D has ended. Thus, in the medium output mode where the power range in which power can be supplied is lower than that in the high output mode, it is possible to adjust so as not to overlap the execution of the reading process and the execution of the first wireless output process. Therefore, the functions related to image reading can be realized according to the power consumption.

[0297] (35) Also, the time from the start to the end of the reading process of reading an image from a predetermined number of original documents D among the plurality of original documents D can be shortened. Also, the first wireless output process can be executed at a timing considering the data capacity of the image data of the predetermined number of original documents D that can be stored in the image data storage unit 54A.

[0298] [Modified Example] This embodiment can be implemented with the following modifications. This embodiment and the following modified examples can be implemented in combination with each other within a technically non - conflicting range.

[0299] · In the above embodiment, the image reading device 11 may include a battery, for example, if it can be connected to a battery. That is, the image reading device 11 may, for example, incorporate a battery.

[0300] In the above embodiment, the control unit 50 functions as an image processing unit 54, but for example, in low-output mode, it may output the digital signal itself from the analog front-end 56 without performing image processing. The control unit 50 may output the digital signal itself from the analog front-end 56 without performing image processing in low-output mode and medium-output mode, for example.

[0301] In the above embodiment, for example, the image reading device 11 may include sensors other than the plurality of sensors related to image reading, and may not include at least one of the plurality of sensors related to image reading.

[0302] In the above embodiment, for example, at least one of the following can be achieved by user operation: moving the paper feed tray 16, moving the paper output tray 17, and changing the orientation of the housing 12. This makes it possible to achieve this by user operation even if at least one of the following is disabled: moving the paper feed tray 16, moving the paper output tray 17, and changing the orientation of the housing 12. For example, at least one of the following does not need to be achieved by driving the drive source: moving the paper feed tray 16, moving the paper output tray 17, and changing the orientation of the housing 12. In other words, for example, the paper feed tray 16 does not need to move. Also, for example, the paper output tray 17 does not need to move. Also, for example, the orientation of the housing 12 does not need to be changed.

[0303] In the above embodiment, for example, the control unit 50 may increase the illuminance of the backlight of the liquid crystal display unit 30 in high-output mode and medium-output mode, and decrease the illuminance of the backlight of the liquid crystal display unit 30 in low-output mode.

[0304] In the above embodiment, for example, the control unit 50 may disable the notification unit 28 in low-output mode. In the above embodiment, for example, the image reading device 11 does not need to include a touch panel 29. For example, the image reading device 11 does not need to include a liquid crystal display unit 30. For example, the image reading device 11 does not need to include an operation unit 27. For example, the image reading device 11 does not need to include a notification unit 28.

[0305] In the above embodiment, for example, the control unit 50 may display an image on the liquid crystal display unit 30 that can identify the controlled mode. In other words, the liquid crystal display unit 30 may be a notification unit that notifies the controlled mode.

[0306] In the third embodiment, for example, the predetermined number of images may be predetermined. Also, for example, the predetermined number of images may vary depending on the size of the image data. Also, for example, the predetermined number of images only needs to be at least that can be stored in the image data storage unit 54A, and does not need to be the upper limit of what can be stored in the image data storage unit 54A.

[0307] In the second and third embodiments, the control unit 50 may divide the output processing period for outputting image data from one document D into multiple non-contiguous periods. For example, the control unit 50 may perform wireless output processing for one document D after the completion of the reading process for the first document D and before the start of the reading process for the second document D, and interrupt the execution of the wireless output processing when the reading process for the second document D begins. The control unit 50 may resume the execution of the interrupted wireless output processing after the completion of the reading process for the second document D and before the start of the reading process for the third document D. This makes it possible to shorten the time from the start to the end of the reading process for reading images from multiple documents D. It also makes it possible to speed up the timing of wireless communication for outputting image data of images read from multiple documents D.

[0308] In the above embodiment, the control unit 50 may, for example, output image data via various communication methods, and may output image data again after a restart. In other words, the control unit 50 may interrupt the output of image data when it is outputting image data via various communication methods. In this case, the control unit 50 may resume outputting image data from the point of interruption, or may resume outputting image data in units of original document D.

[0309] In the above embodiment, the control unit 50 may, for example, restart after terminating the output of image data if the read cancellation condition is not met but the restart condition is met while outputting image data via various communication methods.

[0310] In the above embodiment, the first wireless communication may be another wireless communication, such as Wi-Fi®. The second wireless communication may be another wireless communication, such as Bluetooth®. In other words, the first wireless communication is preferably one that consumes more power than the second wireless communication. The first wireless communication may be, for example, Bluetooth®. Also, for example, the second wireless communication may not be possible.

[0311] In the above embodiment, for example, in low-power mode, the second wireless output process may be executed either before or after the completion of the reading process. For example, in low-power mode, the first wireless output process may not be executed before the completion of the reading process, but may be executed after the completion of the reading process.

[0312] In the above embodiment, for example, in high-power mode, the second wireless output processing may be performed with priority over wired output processing. For example, in high-power mode, the first wireless output processing may be performed with priority over wired output processing. For example, in high-power mode, the first wireless output processing may be performed with priority over the second wireless output processing.

[0313] In the above embodiment, for example, in medium output mode, the second wireless output processing may be performed with priority over wired output processing. For example, in medium output mode, the first wireless output processing may be performed with priority over wired output processing. For example, in medium output mode, the first wireless output processing may be performed with priority over the second wireless output processing.

[0314] In the above embodiment, for example, in low-power mode, the second wireless output processing may be performed with priority over wired output processing. For example, in low-power mode, the first wireless output processing may be performed with priority over wired output processing. For example, in low-power mode, the first wireless output processing may be performed with priority over the second wireless output processing.

[0315] In the above embodiment, the first device may include, for example, at least one of a medium-power USB device and a battery, but may also include other devices. The second device may include, for example, at least one of a high-power USB device and an AC adapter, but may also include other devices.

[0316] In the above embodiment, the control unit 50 may, for example, control the device to either medium output mode or low output mode instead of high output mode when at least one of an AC adapter and a high-power USB device is connected.

[0317] In the above embodiment, the control unit 50 may, in the medium output mode, control the same content as in the low output mode, for example, in the same way as in the high output mode, unlike in the low output mode. As a specific example, the control unit 50 may enable and control the double feed sensor 35 in both the high output mode and the medium output mode.

[0318] In the above embodiment, the control unit 50 may, in the medium output mode, control the same control content as in the high output mode, for example, in the same way as in the low output mode, unlike in the high output mode. As a specific example, the control unit 50 may not drive the attitude drive motor 49 in the medium output mode and the low output mode.

[0319] In the above embodiment, for example, the control unit 50 only needs to control at least one of the control contents corresponding to each of the multiple types of modes shown in Figure 4. In the above embodiment, for example, the control unit 50 may, in high-output mode and medium-output mode, continue reading the image at 5 ppm based on a read instruction when a power value within the low-power range is supplied due to a change in the connection state, without interrupting the image reading. In this case, for example, the control unit 50 may control to low-output mode while reading the image based on the read instruction, or to low-output mode after the completion of reading the image based on the read instruction. Also, for example, the control unit 50 does not need to be restarted.

[0320] In the above embodiment, for example, the control unit 50 may, in high-output mode, continue reading the image at 30 ppm based on a read instruction when a power value within the medium power range is supplied due to a change in the connection state, without interrupting the image reading. In this case, for example, the control unit 50 may be controlled to medium output mode during image reading based on a read instruction, or to medium output mode after the completion of image reading based on a read instruction. Also, for example, the control unit 50 does not need to be restarted.

[0321] In the above embodiment, for example, the control unit 50 may, in medium output mode and low output mode, continue reading the image at 5 ppm based on a read instruction when a power value included in the high power range is supplied due to a change in the connection state, without interrupting the image reading. In this case, for example, the control unit 50 may control to high output mode during image reading based on a read instruction, or control to high output mode after the completion of image reading based on a read instruction. Also, for example, the control unit 50 may use equipment corresponding to high output mode as a power source during image reading based on a read instruction, or use equipment corresponding to high output mode as a power source after the completion of image reading based on a read instruction. Furthermore, for example, the control unit 50 does not need to be restarted.

[0322] In the above embodiment, for example, the control unit 50 may, in low-output mode, continue reading the image at 5 ppm based on a read instruction when a power value within the medium power range is supplied due to a change in the connection state, without interrupting the image reading. In this case, for example, the control unit 50 may control to medium output mode during image reading based on a read instruction, or control to medium output mode after the completion of image reading based on a read instruction. Also, for example, the control unit 50 may use a device corresponding to medium output mode as a power source during image reading based on a read instruction, or use a device corresponding to medium output mode as a power source after the completion of image reading based on a read instruction. Furthermore, for example, the control unit 50 does not need to be restarted.

[0323] In the above embodiment, for example, the control unit 50 may, in medium output mode, continue reading the image at 30 ppm based on a read instruction when a power value included in the high power range is supplied due to a change in the connection state, without interrupting the image reading. In this case, for example, the control unit 50 may control to high output mode while reading the image based on the read instruction, or control to high output mode after the completion of reading the image based on the read instruction. Also, for example, the control unit 50 may use a device corresponding to high output mode as a power source while reading the image based on the read instruction, or use a device corresponding to high output mode as a power source after the completion of reading the image based on the read instruction. Furthermore, for example, the control unit 50 does not need to be restarted.

[0324] In the above embodiment, for example, the control unit 50 does not need to be restarted when changing modes. For example, the control unit 50 does not need to be restarted when changing modes to lower the power range. For example, the control unit 50 does not need to be restarted when changing modes to increase the power range.

[0325] In the above embodiment, for example, the image reading device 11 may be configured to read images at any of two or four or more types of reading speeds. Also, for example, the reading speed may be any speed.

[0326] In the above embodiment, four USB standards were given as examples, but the present invention is not limited to these, and may be applied to, for example, two, three, or five or more standards. In other words, it is sufficient that multiple USB devices capable of supplying power values ​​within different power ranges can be connected. Furthermore, for example, each power range may be any range.

[0327] In the above embodiment, for example, the image reading device 11 may have multiple USB connection units 64. That is, the image reading device 11 can connect to multiple USB devices. In this case, the control unit 50 may determine the power supply source from among the multiple USB devices according to priority. The control unit 50 may also control the mode from among the multiple USB devices according to priority.

[0328] In the above embodiment, for example, the USB device may be a host device or a device device. In the above embodiment, for example, the AC adapter, battery, and USB device may be within any power range. Also, for example, the AC adapter, battery, and USB device may have the same or different power values, as long as they can supply power within the same power range.

[0329] In the above embodiment, five power sources were exemplified: an AC adapter, a battery, a high-power USB device, a medium-power USB device, and a low-power USB device, but the invention is not limited to these. For example, the image reading device 11 may be powered by any of two to four or six or more power sources. In other words, the power supply may include, for example, power sources other than those exemplified above, or it may not include at least one of the power sources exemplified above.

[0330] In the above embodiment, three modes were adopted as the multiple modes, but this is not limited to this. For example, any two or four or more modes may be adopted as the multiple modes.

[0331] In the above embodiment, for example, the control unit 50 does not have to perform enumeration with the USB device when the power is turned on. For example, the control unit 50 does not have to perform enumeration with the USB device when there is a change in the connection state with the USB device. In other words, the control unit 50 may perform enumeration with the USB device when the power is turned on or when there is a change in the connection state with the USB device.

[0332] In the above embodiment, various controls were performed on the condition that the image was not being read based on a read instruction, but this is not limited to this. For example, even when the image is being read based on a read instruction, various controls may be performed when the reading unit 40 is not actually reading the image. In other words, during the control period based on the read instruction, various controls may be performed during the non-reading period when the reading unit 40 is not actually reading the image. Thus, various controls may be performed on the condition that the image is not being read. Examples of various controls may include changing the power supply source, changing the mode, wireless communication, and charging the battery.

[0333] In the above embodiment, even if the battery charge level is above the upper limit, if image reading is performed for a long period of time, the control unit 50 may control the system to a low output mode without using the battery as a power source.

[0334] The image sensor 42 is not limited to a CMOS image sensor. The image sensor 42 may be, for example, a MOS (Metal Oxide Semiconductor) image sensor, or for example, a CCD (charge coupled device) image sensor.

[0335] The image sensor 42 is not limited to a linear image sensor, but may also be an area image sensor, for example. The material of the original document is not limited to paper; for example, it may be made of resin film or sheet, fabric, metal film, etc.

[0336] The image reading device may be part of a multifunction device that includes not only scanning but also printing and copying functions. The image reading device is not limited to a sheet-fed type; it may also be a flatbed type. A flatbed image reading device comprises a carriage and a carriage motor. The carriage is movable along the main scanning direction D2 by the drive of the carriage motor. The reading unit is mounted on the carriage.

[0337] • The present invention is applicable to image reading devices, but is also applicable to control methods for image reading devices. [Note] The following describes the technical concepts and their effects that can be understood from the embodiments and modifications described above.

[0338] (A) The device comprises a reading unit configured to read an image from a document, and a control unit configured to perform control related to image reading, wherein the control unit is controllable to any of a plurality of modes, the plurality of modes including a low-power mode and a high-power mode, the low-power mode being a controllable mode in a connected state where a low-power USB device capable of supplying power values ​​within a low-power range is connected, and the high-power mode being a controllable mode in a connected state where a high-power USB device capable of supplying power values ​​within a high-power range higher than the low-power range is connected, the reading unit can read an image at either a first reading speed or a second reading speed faster than the first reading speed, the control unit can, in the low-power mode, not perform image reading at the second reading speed but perform image reading at the first reading speed, and in the high-power mode, can perform image reading at the first reading speed and also perform image reading at the second reading speed.

[0339] With this configuration, even if the power supply range of USB devices differs, image reading can be performed at the same first reading speed. On the other hand, even with the same USB device, image reading can be performed at a second reading speed faster than the first reading speed, depending on the power supply range of the USB device. In this way, image reading can be performed at a reading speed corresponding to the power supply range of the USB device. Therefore, image reading functions can be implemented according to power consumption.

[0340] (B) The high-power mode is a mode that can be controlled when an AC adapter capable of supplying power values ​​within the high-power range is connected. This configuration can achieve the same effect as (A).

[0341] (C) When the AC adapter and the high-power USB device are connected, the control unit may use the AC adapter as a power source and control the device to the high-output mode. In the high-output mode, when the connection state changes from one in which the AC adapter and the high-power USB device are connected to one in which the high-power USB device is connected but the AC adapter is not, the control unit may use the high-power USB device as a power source and continue control in the high-output mode.

[0342] With this configuration, even if the AC adapter is not connected, if a high-power USB device is connected, the power supply source can be switched from the AC adapter to the high-power USB device, and control in high-output mode can be continued. Therefore, image reading functions can be implemented according to power consumption.

[0343] (D) When the AC adapter and the low-power USB device are connected, the control unit may use the AC adapter as a power source and control it to the high-output mode. In the high-output mode, while reading an image at the second reading speed, if the connection state changes from one in which the AC adapter and the low-power USB device are connected to one in which the low-power USB device is connected but the AC adapter is not, the control unit may stop reading the image at the second reading speed.

[0344] With this configuration, if the AC adapter is disconnected while reading an image at the second reading speed, the image reading can be stopped when the available power range decreases. Therefore, the image reading function can be implemented according to the power consumption.

[0345] (E) When the AC adapter and the low-power USB device are connected, the control unit may use the AC adapter as a power source and control it to the high-output mode. In the high-output mode, while reading an image at the first reading speed, if the connection state changes from one in which the AC adapter and the low-power USB device are connected to one in which the low-power USB device is connected but the AC adapter is not, the control unit may stop reading the image at the first reading speed.

[0346] With this configuration, if the AC adapter is not connected during image reading at the first reading speed, the power supply range decreases even if a low-power USB device is connected. As a result, even during image reading at the first reading speed, image reading will not continue when the power supply range decreases, and control will be performed to stop the reading. Therefore, image reading functions can be implemented according to power consumption.

[0347] (F) When the AC adapter is not connected and the low-power USB device is connected, the control unit may use the low-power USB device as a power source and control the unit to the low-output mode. In the low-output mode, when reading an image at the first reading speed, the connection state changes from one where the AC adapter is not connected and the low-power USB device is connected to one where the AC adapter and the low-power USB device are connected, the control unit may continue to use the low-power USB device as a power source and continue control in the low-output mode. After the reading of the image at the first reading speed is completed, the control unit may use the AC adapter as a power source and control the unit to the high-output mode.

[0348] With this configuration, even if the AC adapter is connected while an image is being read at the first reading speed, the power supply range does not increase, and the low-power USB device continues to be used as the power source, and control in low-output mode continues. As a result, by continuing to use the power source and mode without changing them while reading an image at the first reading speed, stable image reading can be maintained. Therefore, the image reading functions can be implemented according to the power consumption.

[0349] In addition, after image reading at the first reading speed is completed, the power supply range can be increased by using the AC adapter as the power source, and control in high-output mode can be initiated. Therefore, image reading functions can be implemented according to power consumption.

[0350] (G) When the AC adapter is not connected and the high-power USB device is connected, the control unit may use the high-power USB device as a power source and control the unit to the high-output mode. In the high-output mode, when reading an image at the second reading speed, the connection state changes from one in which the AC adapter is not connected and the high-power USB device is connected to one in which the AC adapter and the high-power USB device are connected, the control unit may continue to use the high-power USB device as a power source and continue control in the high-output mode. After the reading of the image at the second reading speed is completed, the control unit may use the AC adapter as a power source and continue control in the high-output mode.

[0351] With this configuration, even if the AC adapter is connected during image reading at the second reading speed, if a high-power USB device is connected, the high-power USB device will continue to be the power source, and control in high-output mode will continue. This allows for stable image reading to continue without changing the power source or mode during image reading at the second reading speed. Therefore, image reading functions can be implemented according to power consumption.

[0352] In addition, after image reading at the second reading speed is completed, the power supply can be changed to the AC adapter by using the AC adapter as the power source, and control in high-output mode can be continued. Therefore, image reading functions can be implemented according to power consumption.

[0353] (H) The multiple types of modes include a medium output mode, the medium output mode being a controllable mode in a connected state where a medium-power USB device capable of supplying a power value in the medium power range which is higher than the low power range and lower than the high power range is connected, the reading unit can read images at a third reading speed which is faster than the first reading speed and slower than the second reading speed, and the control unit may, in the medium output mode, not perform image reading at the second reading speed but perform image reading at the first reading speed and may also perform image reading at the third reading speed.

[0354] This configuration allows control to a medium output mode in addition to low and high output modes. Even with the same USB device, it is possible to provide diversity in the power range that the USB device can supply and the reading speed corresponding to that power range. Therefore, image reading functions can be implemented according to power consumption.

[0355] (I) The control unit comprises a first tray on which a document to be scanned can be placed, and a first tray drive source that can move the first tray, wherein the control unit does not drive the first tray drive source in the low output mode, but may drive the first tray drive source in the high output mode.

[0356] With this configuration, the first tray drive source is not driven in the low-power mode, which has a lower power range than the high-power mode, thus reducing power consumption. Therefore, image reading functions can be implemented according to power consumption.

[0357] (J) The control unit comprises a second tray on which scanned documents can be placed, and a second tray drive source that can move the second tray, wherein the control unit does not drive the second tray drive source in the low output mode, but may drive the second tray drive source in the high output mode.

[0358] With this configuration, the second tray drive source is not driven in the low-power mode, which has a lower power range than the high-power mode, thus reducing power consumption. Therefore, image reading functions can be implemented according to power consumption.

[0359] (K) The control unit comprises a base, a housing supported by the base, and a housing drive source that drives the housing so as to change its orientation, wherein the control unit does not drive the housing drive source in the low-output mode, but may drive the housing drive source in the high-output mode.

[0360] With this configuration, the chassis drive source is not driven in the low-power mode, which has a lower power range than the high-power mode, thus reducing power consumption. Therefore, image reading functions can be implemented according to power consumption.

[0361] (L) The system comprises a transport unit configured to transport a document and a carrier sheet sensor for detecting a carrier sheet that holds the document, wherein the transport unit is capable of transporting the carrier sheet, and the control unit may not allow the transport unit to transport the carrier sheet in the low-power mode, but may allow the transport unit to transport the carrier sheet in the high-power mode, and may disable the carrier sheet sensor in the low-power mode, but enable the carrier sheet sensor in the high-power mode.

[0362] With this configuration, in the low-power mode, which has a lower power range than the high-power mode, the carrier sheet, which requires more transport force than the original document (such as thin paper), is not transported, thus reducing power consumption. Furthermore, in the low-power mode, which has a lower power range than the high-power mode, the carrier sheet sensor can be disabled, further reducing power consumption. Therefore, image reading functions can be implemented according to power consumption.

[0363] (M) The control unit comprises a transport unit configured to transport a document and a double-feed sensor for detecting double feeding of documents, wherein the control unit disables the double-feed sensor in the low-power mode, but may enable the double-feed sensor in the high-power mode.

[0364] This configuration allows the double-feed sensor to be disabled in the low-power mode, which has a lower power range than the high-power mode, thereby reducing power consumption. Therefore, image reading functions can be implemented according to power consumption.

[0365] (N) The system includes a sensor that performs detection related to image reading, and the control unit may perform control to switch between an effective period in which the sensor is enabled and an inactive period in which the sensor is disabled in the low-output mode.

[0366] This configuration allows for switching between an inactive period (when the sensor is disabled) and an active period (when the sensor is enabled) in the low-power mode, which has a lower power range than the high-power mode, thereby reducing power consumption. Therefore, image reading functions can be implemented according to power consumption.

[0367] (O) The control unit may perform an enumeration of the connection status with the USB device when the power is turned on or when there is a change in the connection status with the USB device, and determine the connection status with the USB device based on the result of the enumeration.

[0368] With this configuration, the connection status with a USB device can be determined based on at least one of the following: power-on or a change in the connection status with the USB device. Therefore, the image reading function can be implemented according to power consumption.

[0369] (P) The system includes a notification unit configured to provide notification, and the notification unit may provide notification of the mode controlled by the control unit. This configuration allows the user to identify the controlled mode. This, in turn, allows the user to specify the image reading functionality. Therefore, user convenience can be improved.

[0370] (Q) A control method for an image reading device equipped with a reading unit configured to read an image from a document, wherein the device is controllable to any of a plurality of modes, including a low-output mode that can be controlled when a low-power USB device capable of supplying power values ​​within a low-power range is connected, and a high-output mode that can be controlled when a high-power USB device capable of supplying power values ​​within a high-power range higher than the low-power range is connected; in the low-output mode, the device is not allowed to read an image at a second reading speed faster than the first reading speed, but it is allowed to read an image at the first reading speed; and in the high-output mode, the device is allowed to read an image at the first reading speed and also allow it to read an image at the second reading speed. This configuration can achieve the same effect as (A). [Explanation of Symbols]

[0371] D...Document, D1...Sub-scanning direction, D2...Main scanning direction, SA...Reading area, TA...Control table, 11...Image reader, 12...Housing, 13...Base, 14...Supply port, 15...Output port, 15A...First output port, 15B...Second output port, 16...Paper feed tray, 17...Output tray, 18...Transport path, 18A...First transport path, 18B...Second transport path, 19...Common transport path, 20A...Curved path, 20B...Straight path, 21...Transport unit, 22 ...Paper feed roller, 23...First roller pair, 23A...First drive roller, 23B...First separation roller, 24...Second roller pair, 24A...Second drive roller, 24B...Second driven roller, 25...Third roller pair, 25A...Third drive roller, 25B...Third driven roller, 26...Path switching member, 27...Operation unit, 28...Notification unit, 29...Touch panel, 30...LCD display unit, 31...First document sensor, 32...Document protection sensor 33…Document thickness sensor, 34…Carrier sheet sensor, 35…Double feed sensor, 36…Second document sensor, 37…Attitude sensor, 37A…First attitude sensor, 37B…Second attitude sensor, 40…Reading unit, 41…Light source, 42…Image sensor, 43…Background plate, 44…Feed motor, 45…Transport motor, 46…Encoder, 47…Paper feed tray motor, 48…Paper output tray motor, 49…Attitude drive motor, 50…Control unit, 51…Main control unit, 52…Transport control unit, 53…Reading control unit, 54…Image processing unit, 54A…Image data storage unit, 55…Timing generator, 56…Analog front end, 57…First wireless communication unit, 58…Second wireless communication unit, 59…Wired communication unit, 60…Power supply circuit, 60A…Capacitor, 61…Connection unit, 62…AC adapter connection unit, 63…Battery connection unit, 64…USB connection unit

Claims

1. A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The high-power mode is a mode that can be controlled when an AC adapter capable of supplying power values ​​included in the high-power range is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. When the AC adapter and the high-power USB device are connected, the AC adapter is used as the power source and controlled to the high-output mode. In the high-output mode, when the connection state changes from one in which the AC adapter and the high-power USB device are connected to one in which the high-power USB device is connected but the AC adapter is not, the high-power USB device is used as the power source, and control in the high-output mode is continued. An image reading device characterized by the following.

2. In the image reading device according to claim 1, The control unit, When the AC adapter and the low-power USB device are connected, the AC adapter is used as the power source and controlled to the high-output mode. In the high-output mode, when reading an image at the second reading speed, the connection state changes from one in which the AC adapter and the low-power USB device are connected to one in which the low-power USB device is connected but the AC adapter is not connected, the reading of the image at the second reading speed is stopped. An image reading device characterized by the following.

3. In the image reading device according to claim 1 or claim 2, The control unit, When the AC adapter and the low-power USB device are connected, the AC adapter is used as the power source and controlled to the high-output mode. In the high-output mode, when reading an image at the first reading speed, the connection state changes from one in which the AC adapter and the low-power USB device are connected to one in which the low-power USB device is connected but the AC adapter is not connected, the reading of the image at the first reading speed is stopped. An image reading device characterized by the following.

4. In the image reading device according to any one of claims 1 to 3, The control unit, When the AC adapter is not connected and the low-power USB device is connected, the low-power USB device is used as the power source and the system is controlled to the low-output mode. In the low-power mode, when reading an image at the first reading speed, the connection state changes from one where the AC adapter is not connected and the low-power USB device is connected to one where the AC adapter and the low-power USB device are connected, the low-power USB device continues to be used as the power source, control in the low-power mode continues, and after the reading of the image at the first reading speed is completed, the AC adapter becomes the power source, and control switches to the high-power mode. An image reading device characterized by the following.

5. In the image reading device according to any one of claims 1 to 4, The control unit, When the AC adapter is not connected and the high-power USB device is connected, the high-power USB device is used as the power source and controlled to the high-output mode. In the high-output mode, when reading an image at the second reading speed, the connection state changes from one where the AC adapter is not connected and the high-power USB device is connected to one where the AC adapter and the high-power USB device are connected, the high-power USB device continues to be used as the power source, and control in the high-output mode continues. After the reading of the image at the second reading speed is completed, the AC adapter becomes the power source, and control in the high-output mode continues. An image reading device characterized by the following.

6. In the image reading device according to any one of claims 1 to 5, The aforementioned multiple types of modes include a medium output mode, The aforementioned medium output mode is a mode that can be controlled when a medium-power USB device capable of supplying power values ​​within the medium power range, which is higher than the low power range and lower than the high power range, is connected. The reading unit can read the image at a third reading speed that is faster than the first reading speed and slower than the second reading speed. The control unit, in the medium output mode, does not perform image reading at the second reading speed, but can perform image reading at the first reading speed, and can also perform image reading at the third reading speed. An image reading device characterized by the following.

7. In the image reading device according to any one of claims 1 to 6, A first tray on which the original document can be placed before scanning, A first tray drive source that can move the first tray, Equipped with, The control unit does not drive the first tray drive source in the low-power mode, but can drive the first tray drive source in the high-power mode. An image reading device characterized by the following.

8. In the image reading device according to any one of claims 1 to 7, A second tray on which scanned documents can be placed, A second tray drive source that can move the aforementioned second tray, Equipped with, The control unit does not drive the second tray drive source in the low-power mode, but can drive the second tray drive source in the high-power mode. An image reading device characterized by the following.

9. In the image reading device according to any one of claims 1 to 8, Base and, The housing supported by the base, A housing drive source that drives the housing so that its orientation can be changed, Equipped with, The control unit does not drive the housing drive source in the low-output mode, but can drive the housing drive source in the high-output mode. An image reading device characterized by the following.

10. In the image reading device according to any one of claims 1 to 9, A transport unit configured to transport a document, It includes a carrier sheet sensor that detects the carrier sheet in which the document is placed, The transport unit is capable of transporting carrier sheets, The control unit, In the low-power mode, the carrier sheet is not transported by the transport unit, but in the high-power mode, the carrier sheet can be transported by the transport unit. In the low-power mode, the carrier sheet sensor is disabled, but in the high-power mode, the carrier sheet sensor is enabled. An image reading device characterized by the following.

11. In the image reading device according to any one of claims 1 to 10, A transport unit configured to transport a document, It is equipped with a double-feed sensor that detects double feeding of documents, The control unit disables the double feed sensor in the low-power mode, but enables the double feed sensor in the high-power mode. An image reading device characterized by the following.

12. In the image reading device according to any one of claims 1 to 11, Equipped with a sensor that performs detection related to image reading, The control unit can perform control to switch between an active period in which the sensor is enabled and an inactive period in which the sensor is disabled in the low-output mode. An image reading device characterized by the following.

13. In the image reading device according to any one of claims 1 to 12, The control unit performs an enumeration of the connection status with the USB device when power is turned on or when there is a change in the connection status with the USB device, and determines the connection status with the USB device based on the result of the enumeration. An image reading device characterized by the following.

14. In the image reading device according to any one of claims 1 to 13, It includes a notification unit configured to provide notification, The notification unit notifies the mode controlled by the control unit. An image reading device characterized by the following.

15. A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The high-power mode is a mode that can be controlled when an AC adapter capable of supplying power values ​​included in the high-power range is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. When the AC adapter and the low-power USB device are connected, the AC adapter is used as the power source and controlled to the high-output mode. In the high-output mode, when reading an image at the second reading speed, the connection state changes from one in which the AC adapter and the low-power USB device are connected to one in which the low-power USB device is connected but the AC adapter is not connected, the reading of the image at the second reading speed is stopped. An image reading device characterized by the following.

16. A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The high-power mode is a mode that can be controlled when an AC adapter capable of supplying power values ​​included in the high-power range is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. When the AC adapter and the low-power USB device are connected, the AC adapter is used as the power source and controlled to the high-output mode. In the high-output mode, when reading an image at the first reading speed, the connection state changes from one in which the AC adapter and the low-power USB device are connected to one in which the low-power USB device is connected but the AC adapter is not connected, the reading of the image at the first reading speed is stopped. An image reading device characterized by the following.

17. A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The high-power mode is a mode that can be controlled when an AC adapter capable of supplying power values ​​included in the high-power range is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. When the AC adapter is not connected and the low-power USB device is connected, the low-power USB device is used as the power source and the system is controlled to the low-output mode. In the low-power mode, when reading an image at the first reading speed, the connection state changes from one where the AC adapter is not connected and the low-power USB device is connected to one where the AC adapter and the low-power USB device are connected, the low-power USB device continues to be used as the power source, control in the low-power mode continues, and after the reading of the image at the first reading speed is completed, the AC adapter becomes the power source, and control switches to the high-power mode. An image reading device characterized by the following.

18. A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The high-power mode is a mode that can be controlled when an AC adapter capable of supplying power values ​​included in the high-power range is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. When the AC adapter is not connected and the high-power USB device is connected, the high-power USB device is used as the power source and controlled to the high-output mode. In the high-output mode, when reading an image at the second reading speed, the connection state changes from one where the AC adapter is not connected and the high-power USB device is connected to one where the AC adapter and the high-power USB device are connected, the high-power USB device continues to be used as the power source, and control in the high-output mode continues. After the reading of the image at the second reading speed is completed, the AC adapter becomes the power source, and control in the high-output mode continues. An image reading device characterized by the following.

19. A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode, a high-power mode, and a medium-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The aforementioned medium output mode is a mode that can be controlled when a medium-power USB device capable of supplying power values ​​within the medium power range, which is higher than the low power range and lower than the high power range, is connected. The reading unit can read an image at any of the following speeds: a first reading speed, a second reading speed faster than the first reading speed, and a third reading speed faster than the first reading speed and slower than the second reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. In the aforementioned medium output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed, and image reading at the third reading speed can also be performed. An image reading device characterized by the following.

20. A first tray on which a document to be scanned can be placed, A first tray drive source that can move the first tray, A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. In the low-power mode, the first tray drive source is not driven, but in the high-power mode, the first tray drive source can be driven. An image reading device characterized by the following.

21. A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, A second tray on which scanned documents can be placed, A second tray drive source that can move the aforementioned second tray, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. In the low-power mode, the second tray drive source is not driven, but in the high-power mode, the second tray drive source can be driven. An image reading device characterized by the following.

22. A base and, The housing supported by the base, A housing drive source that drives the housing so that its orientation can be changed, A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. In the low-power mode, the housing drive source is not driven, but in the high-power mode, the housing drive source can be driven. An image reading device characterized by the following.

23. A transport unit configured to transport a document, A carrier sheet sensor that detects the carrier sheet in which the document is placed, A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The transport unit is capable of transporting carrier sheets, The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. In the low-power mode, the carrier sheet is not transported by the transport unit, but in the high-power mode, the carrier sheet can be transported by the transport unit. In the low-power mode, the carrier sheet sensor is disabled, but in the high-power mode, the carrier sheet sensor is enabled. An image reading device characterized by the following.

24. A transport unit configured to transport a document, A double-feed sensor that detects double feeding of documents, A reading unit configured to read images from a document, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. In the low-power mode, the double-feed sensor is disabled, but in the high-power mode, the double-feed sensor is enabled. An image reading device characterized by the following.

25. A reading unit configured to read images from a document, A sensor that performs detection related to image reading, A control unit configured to perform control related to image reading, Equipped with, The control unit is capable of controlling to any of several modes. The aforementioned multiple types of modes include a low-power mode and a high-power mode. The low-power mode is a mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected. The high-power mode is a mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. The reading unit can read an image at either a first reading speed or a second reading speed that is faster than the first reading speed. The control unit, In the low-output mode, image reading at the second reading speed is not performed, but image reading at the first reading speed can be performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. In the low-power mode, control can be performed to switch between an active period in which the sensor is enabled and an inactive period in which the sensor is disabled. An image reading device characterized by the following.

26. In the image reading device according to any one of claims 15 to 25, The control unit performs an enumeration of the connection status with the USB device when power is turned on or when there is a change in the connection status with the USB device, and determines the connection status with the USB device based on the result of the enumeration. An image reading device characterized by the following.

27. In the image reading device according to any one of claims 15 to 25, It includes a notification unit configured to provide notification, The notification unit notifies the mode controlled by the control unit. An image reading device characterized by the following.

28. In a control method for an image reading device equipped with a reading unit configured to read an image from a document, The device is controllable to any of several modes, including a low-output mode that can be controlled when a low-power USB device capable of supplying power values ​​within the low-power range is connected, and a high-output mode that can be controlled when a high-power USB device capable of supplying power values ​​within the high-power range, which is higher than the low-power range, is connected. In the low-output mode, image reading at a second reading speed faster than the first reading speed is not performed, but image reading at the first reading speed is performed. In the high-output mode, it is possible to perform image reading at the first reading speed and to perform image reading at the second reading speed. In a connected state where an AC adapter capable of supplying power values ​​within the aforementioned high power range is connected to the high-power USB device, the AC adapter is used as the power source and controlled to the high-output mode. In the high-output mode, when the connection state changes from one in which the AC adapter and the high-power USB device are connected to one in which the high-power USB device is connected but the AC adapter is not, the control in the high-output mode is continued using the high-power USB device as the power source. A control method for an image reading device characterized by the following.

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