Document transport device, image processing device, document transport method

Abstract

This invention provides a document transport device, an image processing device, and a document transport method that can achieve a good balance between ease of removing documents from the document output section and securing space for placing documents in the document placement section. [Solution] The transport mechanism (3) sequentially transports the document placed on the document placement section (21) to the document discharge section (22) located below the document placement section (21) via an image reading position from which an image is read from the document. The lifting mechanism (4) raises and lowers the document placement section (21). The first decision processing unit (231) determines whether or not a document is placed on the document placement section (21). The second decision processing unit (232) determines whether or not a document is placed on the document discharge section (22). The lifting processing unit (234) controls the lifting operation of the lifting mechanism (4) based on the determination results of the first decision processing unit (231) and the second decision processing unit (232).

Description

Technical Field

[0001] The present invention relates to a document conveyance device, an image processing device, and a document conveyance method.

Background Art

[0002] Generally, a document conveyance device is known that includes a document placement unit on which a document to be conveyed toward an image reading unit is placed, and a paper discharge tray provided below the document placement unit for discharging the document after the image has been read by the image reading unit. In addition, in this type of document conveyance device, a lifting mechanism for raising and lowering the document placement unit may be provided, and the lifting of the document placement unit may be controlled according to the detection result of the document placed on the document placement unit (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, if the position of the document placement unit is close to the document discharge unit, it becomes difficult to take out the document from the document discharge unit. On the other hand, if the position of the document placement unit is far from the document discharge unit, the amount of documents that can be placed on the document placement unit decreases.

[0005] An object of the present invention is to provide a document conveyance device, an image processing device, and a document conveyance method capable of achieving a good balance between ease of taking out a document from the document discharge unit and ensuring a space for placing a document on the document placement unit.

Means for Solving the Problems

[0006] A document transport device according to one aspect of the present invention comprises a transport mechanism, a lifting mechanism, a first decision processing unit, a second decision processing unit, and a lifting processing unit. The transport mechanism sequentially transports a document placed on a document placement unit through an image reading position where an image is read from the document to a document discharge unit located below the document placement unit. The lifting mechanism raises and lowers the document placement unit. The first decision processing unit determines whether or not a document is placed on the document placement unit. The second decision processing unit determines whether or not a document is placed on the document discharge unit. The lifting processing unit controls the lifting operation of the lifting mechanism based on the determination results of the first and second decision processing units.

[0007] An image processing apparatus according to another aspect of the present invention comprises a document transport device and an image reading unit that reads an image from a document transported by the document transport device.

[0008] Another aspect of the present invention relates to a document transport method, which is performed by one or more processors that control a document transport device. The document transport device comprises a transport mechanism and a lifting mechanism. The transport mechanism sequentially transports a document placed on a document placement section through an image reading position from which an image is read from the document to a document discharge section located below the document placement section. The lifting mechanism raises and lowers the document placement section. The document transport method includes a first step, a second step, and a third step. The first step determines whether or not a document is placed on the document placement section. The second step determines whether or not a document is placed on the document discharge section. The third step controls the lifting operation of the lifting mechanism based on the determination results of the first and second steps. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a document transport device, an image processing device, and a document transport method that can achieve a good balance between ease of removal of documents from the document discharge section and securing space for placing documents in the document placement section. [Brief explanation of the drawing]

[0010] [Figure 1] Figure 1 is a schematic diagram showing the configuration of an image processing apparatus according to an embodiment of the present invention. [Figure 2] Figure 2 is a schematic block diagram of an image processing apparatus according to an embodiment of the present invention. [Figure 3] Figure 3 is a schematic diagram showing the configuration of a document transport device according to an embodiment of the present invention. [Figure 4] Figure 4 is a flowchart showing an example of processing performed by an image processing apparatus according to an embodiment of the present invention. [Figure 5] Figure 5 is a flowchart showing an example of processing performed by an image processing apparatus according to an embodiment of the present invention. [Modes for carrying out the invention]

[0011] The embodiments of the present invention will be described below with reference to the attached drawings. The following embodiments are examples that embody the present invention and are not intended to limit the technical scope of the present invention.

[0012] First, the overall configuration of the image processing apparatus 1 according to this embodiment will be described with reference to Figures 1 to 3.

[0013] For the sake of explanation, the vertical direction is defined as the up-down direction D1 when the image processing device 1 is in a usable installation state (as shown in Figure 1). The direction perpendicular to the plane of the paper of the image processing device 1 shown in Figure 1 is defined as the front-to-back direction D2, and the front side of Figure 1 is defined as the front. Furthermore, the left side of the plane of Figure 1 is defined as the left side, and the left-to-right direction D3 is defined.

[0014] [Image processing device] The image processing device 1 according to this embodiment is, for example, a multifunction device that has the function of executing multiple jobs such as a scan job for reading an image (image data) from a document, a print job for forming an image based on the image data, a facsimile job, and a copy job. The image processing device 1 may be at least a scanner, facsimile device, and copier capable of executing scan jobs.

[0015] As shown in Figures 1 and 2, the image processing device 1 comprises a document transport device 2, an image reading unit 11, an image forming unit 12, a paper feeding unit 13, an operation display unit 14, and a control unit 15. In this embodiment, as shown in Figure 2, the image processing device 1 comprises a housing 100. The document transport device 2, the image reading unit 11, the image forming unit 12, the paper feeding unit 13, the operation display unit 14, and the control unit 15 are provided in the housing 100.

[0016] In this embodiment, the document transport device 2 is an automatic document feeder (ADF). The document transport device 2 transports the document Sh1, which is the object to be read, and whose image is read by the image reading unit 11. As shown in Figure 3, the document transport device 2 includes a document placement unit 21, a document discharge unit 22, a transport mechanism 3, a lifting mechanism 4, a paper feed detection unit 5, a position detection unit 6, a paper discharge detection unit 7, a full load detection unit 8, etc. By driving the transport mechanism 3, the document transport device 2 transports the document Sh1 set in the document placement unit 21, passing it through the image reading position P1 by the image reading unit 11 to the document discharge unit 22.

[0017] The image reading unit 11 reads an image from the original document Sh1 and outputs image data corresponding to the read image. The image reading unit 11 includes a document glass, a light source, multiple mirrors, an optical lens, and a CCD (Charge Coupled Device), etc. For example, the image reading unit 11 reads an image from the original document Sh1 as it passes the image reading position P1 while being transported by the document transport device 2.

[0018] The image forming unit 12 forms an image on the sheet Sh2 based on the image data output from the image reading unit 11. Also, the image forming unit 12 forms an image on the sheet Sh2 based on the image data input to the image processing apparatus 1 from an information processing apparatus such as a personal computer. In this embodiment, as an example, as shown in FIG. 1, the image forming unit 12 includes a transfer device 121, a fixing device 122, a document discharge unit 123, etc., and forms an image on the sheet Sh2 by an electrophotographic method. The image forming unit 12 is not limited to a configuration for forming monochrome images, and may be a configuration for forming full-color images using four colors of C (cyan), M (magenta), Y (yellow), and K (black). Also, the image forming unit 12 may be a configuration for forming an image on the sheet Sh2 by an image forming method other than the electrophotographic method, such as an inkjet method.

[0019] The paper feeding unit 13 supplies the sheet Sh2 to the image forming unit 12. The paper feeding unit 13 has a plurality of paper feed cassettes 131, a manual feed tray, a plurality of conveyance rollers, etc. The paper feeding unit 13 conveys the sheet Sh2 through a conveyance path by a plurality of conveyance rollers or the like from a plurality of paper feed cassettes 1,31 or a manual feed tray, etc., and supplies it to the image forming unit 12. The image forming unit 12 forms an image on the sheet Sh2 supplied through the conveyance path from the paper feeding unit 13.

[0020] The operation display unit 14 is a user interface in the image processing apparatus 1. The operation display unit 14 has a display unit such as a liquid crystal display for displaying various information in accordance with a control instruction from the control unit 15, and an operation unit such as a switch or a touch panel for inputting various information to the control unit 15 in accordance with a user's operation.

[0021] The control unit 15 comprehensively controls the image processing apparatus 1. The control unit 15 mainly consists of a computer system having one or more processors and one or more memories. In the image processing apparatus 1, the functions of the control unit 15 are realized by one or more processors executing a program. The program may be pre-recorded in one or more memories, may be provided through a telecommunication line such as the Internet, or may be provided by being recorded on a non-temporary recording medium readable by a computer system, such as a memory card or an optical disk. The one or more processors are composed of one or more electronic circuits including semiconductor integrated circuits. Furthermore, the computer system referred to in the present disclosure includes a microcontroller having one or more processors and one or more memories. The control unit 15 may be a control unit provided separately from the main control unit that comprehensively controls the image processing apparatus 1.

[0022] Also, the image processing apparatus 1 further includes a storage unit, a communication unit, a power supply unit, etc. The storage unit includes one or more non-volatile memories, and information such as a control program for causing the control unit 15 to execute various processes is pre-stored therein. The communication unit is an interface that executes data communication between the image processing apparatus 1 and an external device connected via a communication network such as the Internet or a LAN (Local Area Network). The power supply unit is a power supply circuit that generates (outputs) power for the operation of the image processing apparatus 1.

[0023] [Document Feeding Device] Next, while referring to FIG. 3, the configuration of the document feeding device 2 according to the present embodiment will be described in more detail.

[0024] The document feeding device 2 is a device that conveys the document Sh1 from the document placement unit 21 to the document discharge unit 22. Also, the document Sh1 is paper as an example in the present embodiment, but is not limited to paper and may be other sheets such as a resin film.

[0025] The document placement section 21 is a component on which the document Sh1, which is to be transported by the document transport device 2, is placed. In this embodiment, the document Sh1 transported by the document transport device 2 is the object of image reading by the image reading section 11.

[0026] The document placement section 21 is provided with a paper feed detection unit 5 that detects when a document Sh1 is placed on the document placement section 21. The control unit 15 can use the paper feed detection unit 5 to detect the presence or absence of a document Sh1 in the document placement section 21. Specifically, the paper feed detection unit 5 is an optical sensor comprising a light irradiation unit that irradiates light toward the placement area of ​​the document Sh1 in the document placement section 21 and a light receiving unit that receives light from below the document placement section 21.

[0027] The paper feed detection unit 5 inputs a document presence signal to the control unit 15 indicating that a document Sh1 is placed on the document placement unit 21 when a document Sh1 is placed on the document placement unit 21, light emitted from the light irradiation unit is reflected by the document Sh1, and a predetermined amount of light is received by the light receiving unit. The paper feed detection unit 5 also inputs a document absence signal to the control unit 15 indicating that a document Sh1 is not placed on the document placement unit 21 when a document Sh1 is not placed on the document placement unit 21, light emitted from the light irradiation unit is not reflected by the document Sh1, and a predetermined amount of light is not received by the light receiving unit. In other embodiments, the paper feed detection unit 5 may be other sensors such as an ultrasonic sensor or a contact sensor.

[0028] The document placement section 21 can accommodate documents Sh1 of various sizes (paper sizes), such as A3E (A3 landscape), B4E (A4 landscape), 2L size, L size, postcards, or business cards. The document placement section 21 has a pair of cursors facing each other in the front-to-back direction D2, and the distance between the pair of cursors is adjusted to match the dimensions of the placed document Sh1 in the horizontal direction (in this case, the front-to-back direction D2) which is perpendicular to the vertical direction (transport direction).

[0029] The document placement section 21 is set with one or more documents Sh1 that are to be transported by the document transport device 2. When multiple documents Sh1 are set in the document placement section 21, these multiple documents Sh1 are stacked in the vertical direction D1, that is, stacked, and placed in the document placement section 21.

[0030] The document discharge section 22 is a component on which the document Sh1 transported by the document transport device 2 is discharged and placed. The document discharge section 22 is located below the document placement section 21. The document transport device 2 transports the document Sh1 placed on the document placement section 21 through the image reading position P1 where image processing by the image processing unit is performed, and discharges it onto the document discharge section 22. In this embodiment, since the document Sh1 transported by the document transport device 2 is the target of image reading by the image reading unit 11, the document Sh1 after image reading by the image reading unit 11 is discharged onto the upper surface of the document discharge section 22.

[0031] Here, the document output unit 22 can accommodate documents Sh1 of various sizes (paper sizes), just like the document placement unit 21. Furthermore, when multiple documents Sh1 are output to the document output unit 22, these multiple documents Sh1 are placed in the document output unit 22 stacked in the vertical direction D1, that is, in a stacked state, just like in the document placement unit 21.

[0032] In the image processing device 1, the amount of documents that can be placed in the document ejection unit 22 (hereinafter referred to as the "specific amount") is set in advance. Specifically, in this embodiment, the specific amount is defined by the height of the documents Sh1 in the document ejection unit 22. The image processing device 1 is provided with a full load detection unit 8, which will be described later, to detect whether the height of the documents Sh1 placed in the document ejection unit 22 has reached a specific height corresponding to the specific amount.

[0033] The transport mechanism 3 sequentially transports the document Sh1 placed on the document placement section 21 to the document discharge section 22 through the image reading position P1 where the image of the document Sh1 is read. Specifically, as shown by the dashed arrow in Figure 3, the transport mechanism 3 transports the document Sh1 downwards while transporting it to the left from the document placement section 21, then turns back to the right and discharges it onto the document discharge section 22 through the image reading position P1.

[0034] The transport mechanism 3 includes, for example, a plurality of transport rollers 31 and a power source. The transport rollers 31 include a paper feed roller 31A for feeding the uppermost document Sh1 placed on the document placement section 21 to the transport mechanism 3. In this embodiment, the paper feed roller 31A is provided above the document placement section 21, and the document Sh1 on the document placement section 21 is fed when it comes into contact with the paper feed roller 31A. Therefore, the amount of document Sh1 that can be placed on the document placement section 21 increases as the distance between the document placement section 21 and the paper feed roller 31A increases, and decreases as the distance between the document placement section 21 and the paper feed roller 31A decreases. The transport mechanism 3 is also provided with a paper feed sensor (not shown) that detects when the document Sh1 on the document placement section 21 comes into contact with the paper feed roller 31A.

[0035] The transport mechanism 3, for example, uses the power of a power source including a motor to drive each of the multiple transport rollers 31, thereby transporting the documents Sh1 set on the document placement unit 21 one by one, passing them through the image reading position P1 to the document discharge unit 22. For example, when a predetermined number of documents Sh1 to be processed are set on the document placement unit 21, the transport mechanism 3 transports these predetermined number of documents Sh1 one by one until all of them are discharged onto the document discharge unit 22. As a result, the predetermined number of documents Sh1 to be processed move from the document placement unit 21 to the document discharge unit 22 located below it.

[0036] The lifting mechanism 4 raises and lowers the document rest 21. That is, the document rest 21 is configured to be able to move in the vertical direction D1 within at least a predetermined lifting range. Specifically, the lifting mechanism 4 is configured to be able to switch between an upward movement, which moves the document rest 21 upward relative to the housing 100, and a downward movement, which moves it downward. Furthermore, when neither an upward nor a downward movement is being performed, the lifting mechanism 4 supports the document rest 21 at any position within the lifting range.

[0037] In this embodiment, the lifting mechanism 4 is capable of steplessly moving the document placement section 21 in the vertical direction D1 between the upper and lower limits of the lifting range, and can stop the document placement section 21 at any position within the lifting range. Therefore, for example, by performing an upward movement of the lifting mechanism 4, it is possible to move the document placement section 21, which is at the lower limit of the lifting range, to any position between the lower and upper limits of the lifting range. Conversely, by performing a downward movement of the lifting mechanism 4, it is possible to move the document placement section 21, which is at the upper limit of the lifting range, to any position between the upper and lower limits of the lifting range.

[0038] Specifically, the lifting mechanism 4 includes appropriate mechanical parts and a power source, such as a ball screw, rack and pinion, or pantograph. The lifting mechanism 4 moves the document placement section 21 in a straight line along the vertical direction D1 by driving the aforementioned mechanical parts with power from a power source, including a motor, for example.

[0039] Here, the lifting mechanism 4 may have a sensor such as an encoder in the mechanism or power source, and may have a function to detect the current position of the document placement section 21. This allows the lifting mechanism 4 to raise and lower the document placement section 21 only within the lifting range, and also to move the document placement section 21 to a desired position. For example, it is not necessary to move the document placement section 21 steplessly; it may be moved in steps. Furthermore, the lifting mechanism 4 is not limited to a configuration that moves the document placement section 21 in a straight line in the vertical direction D1, but may also raise and lower the document placement section 21 by rotating the document placement section 21 with one end (left end) in the horizontal direction D3 as a pivot point.

[0040] The position detection unit 6 detects the upper and lower limits of the lifting range of the document placement unit 21. In other words, when the document placement unit 21 is raised by the lifting mechanism 4, the position detection unit 6 detects that the document placement unit 21 has reached the upper limit of the lifting range. Conversely, when the document placement unit 21 is lowered by the lifting mechanism 4, the position detection unit 6 detects that the document placement unit 21 has reached the lower limit of the lifting range.

[0041] Specifically, as shown in Figure 3, the position detection unit 6 has an upper limit sensor 61 and a lower limit sensor 62. Both the upper limit sensor 61 and the lower limit sensor 62 are light-transmitting sensors that include a light-emitting element and a light-receiving element, and their output changes depending on whether or not light from the light-emitting element is received by the light-receiving element. In this embodiment, as an example, the output of the upper limit sensor 61 or the lower limit sensor 62 when light from the light-emitting element is received by the light-receiving element is defined as "on," and the output of the upper limit sensor 61 or the lower limit sensor 62 when light from the light-emitting element is not received by the light-receiving element is defined as "off." The position detection unit 6 outputs the outputs (electrical signals) of the upper limit sensor 61 and the lower limit sensor 62 to the control unit 15.

[0042] Here, the document placement section 21 is provided with a light-shielding plate (not shown), and the upper limit sensor 61 and the lower limit sensor 62 detect the position of the document placement section 21 based on the position of the light-shielding plate, which moves integrally with the document placement section 21. That is, when the document placement section 21 is at the upper limit position of the lifting range, the light-shielding plate is inserted between the light-emitting element and the light-receiving element of the upper limit sensor 61, and the light from the light-emitting element is blocked by the light-shielding plate, so the output of the upper limit sensor 61 is "off". On the other hand, when the document placement section 21 descends to the lower limit position of the lifting range, the light-shielding plate is inserted between the light-emitting element and the light-receiving element of the lower limit sensor 62, and the light from the light-emitting element is blocked by the light-shielding plate, so the output of the lower limit sensor 62 is "off".

[0043] The paper output detection unit 7 is provided in the document output unit 22 and is used to detect whether or not a document Sh1 is placed in the document output unit 22. Specifically, the paper output detection unit 7 is an optical sensor comprising a light irradiation unit that irradiates light upward from the area where the document Sh1 is placed in the document output unit 22 and a light receiving unit that receives light from above the document output unit 22.

[0044] The paper ejection detection unit 7 inputs a document presence signal to the control unit 15 indicating that a document Sh1 is placed on the document ejection unit 22 when the document Sh1 is placed on the document ejection unit 22, the light emitted from the light irradiation unit is reflected by the document Sh1, and a predetermined amount of light is received by the light receiving unit. The paper ejection detection unit 7 also inputs a document absence signal to the control unit 15 indicating that a document Sh1 is not placed on the document ejection unit 22 when the document Sh1 is not placed on the document ejection unit 22, the light emitted from the light irradiation unit is not reflected by the document Sh1, and a predetermined amount of light is not received by the light receiving unit. In other embodiments, the paper ejection detection unit 7 may be other sensors such as an ultrasonic sensor or a contact sensor.

[0045] The full load detection unit 8 is located below the discharge port 220 from which the document Sh1 is discharged from the transport mechanism 3 toward the document discharge unit 22, and is positioned to detect the presence or absence of document Sh1 at a predetermined specific height from the upper surface of the document discharge unit 22. The specific height is the height at which the amount of document Sh1 placed on the document discharge unit 22 reaches the specified amount. In other words, the full load detection unit 8 is used to detect whether or not the amount of document placed on the document discharge unit 22 has reached the specified amount. Hereinafter, the state in which the amount of document Sh1 on the document discharge unit 22 has reached the specified amount may be referred to as the full load state.

[0046] Specifically, the full load detection unit 8 is an optical sensor comprising a light irradiation unit that irradiates light into the space above the document ejection unit 22 at the specified height position of the document ejection unit 22, and a light receiving unit that receives light from the space above the document ejection unit 22.

[0047] The full load detection unit 8 inputs a document presence signal to the control unit 15 when the height of the document Sh1 placed on the document ejection unit 22 reaches the specified height, and the light emitted from the light irradiation unit is reflected by the document Sh1, and a predetermined amount of light is received by the light receiving unit. The full load detection unit 8 also inputs an empty document signal to the control unit 15 when the height of the document Sh1 placed on the document ejection unit 22 reaches the specified height, and the light emitted from the light irradiation unit is not reflected by the document Sh1, and a predetermined amount of light is not received by the light receiving unit. In other embodiments, the full load detection unit 8 may be other sensors such as an ultrasonic sensor or a contact sensor.

[0048] The full load detection unit 8 may also be a distance measuring sensor that measures the height from the document Sh1 on the document ejection unit 22 to the document placement unit 21. The distance measuring sensor is, for example, located on the lower side of the document placement unit 21 and measures the height from the upper surface of the document Sh1 ejected onto the document ejection unit 22 to the lower surface of the document placement unit 21. The distance measuring sensor is, as an example, a non-contact sensor that utilizes reflection of light or ultrasonic waves. As a result, the control unit 15 can detect the amount of document Sh1 placed on the document placement unit 21 based on the height detected by the distance measuring sensor provided as the full load detection unit 8 and the position of the document placement unit 21 in the vertical direction D1.

[0049] Incidentally, in this type of document transport device 2, if the document placement section 21 is close to the document discharge section 22, it becomes difficult to remove the document from the document discharge section 22. On the other hand, if the document placement section 21 is far from the document discharge section 22, the amount of documents that can be placed on the document placement section 21 decreases. In contrast, the image processing device 1 and document transport device 2 according to this embodiment make it possible to achieve a good balance between ease of removing documents from the document discharge section 22 and securing space for placing documents on the document placement section 21, as will be explained below.

[0050] Specifically, the document transport device 2 according to this embodiment includes various processing units such as a first decision processing unit 231, a second decision processing unit 232, a third decision processing unit 233, and a lifting / lowering processing unit 234. In the document transport device 2, the control unit 15 functions as the various processing units by executing various processes according to the control program.

[0051] The first decision processing unit 231 determines whether or not a document is placed on the document placement unit 21. In this embodiment, the first decision processing unit 231 determines whether or not a document is placed on the document placement unit 21 based on the detection result of the paper feed detection unit 5. That is, the first decision processing unit 231 can determine a change in state from a state in which a document is placed on the document placement unit 21 to a state in which no document is placed, and a change in state from a state in which no document is placed on the document placement unit 21 to a state in which a document is placed.

[0052] The second decision processing unit 232 determines whether or not a document is placed in the document ejection unit 22. In this embodiment, the second decision processing unit 232 determines whether or not a document is placed in the document ejection unit 22 based on the detection result of the paper ejection detection unit 7.

[0053] The third decision processing unit 233 determines whether the amount of documents placed in the document discharge unit 22 has reached a predetermined specific amount. In this embodiment, the third decision processing unit 233 determines whether the amount of documents placed in the document discharge unit 22 has reached the specified amount based on the detection result of the full load detection unit 8. Specifically, in the document transport device 2, the discharge port 220 from the transport mechanism 3 to the document discharge unit 22 is provided above the full load detection unit 8. Therefore, in the document transport device 2, if the amount of documents Sh1 in the document discharge unit 22 has not reached the specified amount, the documents Sh1 discharged to the document discharge unit 22 pass through the detection position of the full load detection unit 8, and the documents Sh1 are temporarily detected by the full load detection unit 8. On the other hand, in the document transport device 2, if the amount of documents Sh1 in the document discharge unit 22 has reached the specified amount, the state in which the documents Sh1 discharged to the document discharge unit 22 are detected by the full load detection unit 8 continues. Therefore, the third decision processing unit 233 determines that the document ejection unit 22 is full when the state in which the document Sh1 is detected by the full load detection unit 8 continues for a preset time or longer, that is, when the state in which the H signal is input from the full load detection unit 8 continues for a preset time or longer.

[0054] The lifting / lowering processing unit 234 controls the lifting / lowering operation of the lifting / lowering mechanism 4 based on the judgment results of at least the first judgment processing unit 231 and the second judgment processing unit 232. In particular, in this embodiment, the lifting / lowering processing unit 234 controls the lifting / lowering operation of the lifting / lowering mechanism 4 based on the judgment results of the first judgment processing unit 231, the second judgment processing unit 232, and the third judgment processing unit 233. The lifting / lowering processing unit 234 may return the document placement unit 21 to a preset initial position, such as the lower limit position, when the image processing device 1 is powered on.

[0055] Furthermore, in the image processing device 1, the control unit 15 executes a specific job that involves automatic image reading processing, in which an image is read from a document Sh1 that is transported by the transport mechanism 3 from the document placement unit 21 through the image reading position P1 to the document discharge unit 22. The specific job is a scan job, a copy job, a facsimile job, etc. As the specific job is conventionally known, its explanation will be omitted here, but during the execution of the specific job, the lifting and lowering processing unit 234 controls the lifting and lowering mechanism 4 to raise the document placement unit 21 as needed so that the document Sh1 placed on the document placement unit 21 can be transported by the transport rollers 31.

[0056] Specifically, during the execution of the specific job, the lifting and lowering processing unit 234 controls the lifting and lowering mechanism 4 to raise the document placement unit 21 each time the image reading process for a predetermined number of documents Sh1 is completed, until the paper feed sensor (not shown) detects that the documents Sh1 on the document placement unit 21 have come into contact with the transport rollers 31. Alternatively, during the execution of the specific job, the lifting and lowering processing unit 234 may control the lifting and lowering mechanism 4 to raise the document placement unit 21 when the paper feed sensor (not shown) detects that the documents Sh1 on the document placement unit 21 have separated from the transport rollers 31, until the paper feed sensor (not shown) detects that the documents Sh1 on the document placement unit 21 have come into contact with the transport rollers 31.

[0057] [First Lifting Control Process] Hereinafter, with reference to Figure 4, the first lifting and lowering control process performed by the control unit 15 in the image processing apparatus 1 according to this embodiment will be described. In this embodiment, a method including one or more steps performed in the first lifting and lowering control process and the second lifting and lowering control process described later is an example of the document transport method according to the present invention.

[0058] The first lifting and lowering control process is executed by the control unit 15 when the power to the image processing device 1 is turned on, but it is not executed when the specific job is being executed, and is resumed when the specific job has finished and the second lifting and lowering control process described later has finished. In other words, the first lifting and lowering control process is executed while the image processing device 1 is waiting for a job to be executed.

[0059] Here, steps S1, S2, etc. in Figure 4 represent the processing procedure (step) numbers executed by the control unit 15. The control unit 15 mainly consists of a computer system having one or more processors and one or more memories, and the following processing is realized when one or more processors execute a control program.

[0060] <Step S1> In step S1, the second determination processing unit 232 of the control unit 15 determines whether or not the document Sh1 is placed on the document ejection unit 22. If it is determined that the document Sh1 is placed on the document ejection unit 22 (S1:Yes), the process proceeds to step S2. If it is determined that the document Sh1 is not placed on the document ejection unit 22 (S1:No), the process proceeds to step S11.

[0061] <Step S2> In step S2, the third determination processing unit 233 of the control unit 15 determines whether the document ejection unit 22 is full based on the detection result of the full load detection unit 8. If it is determined that the document ejection unit 22 is full (S2:Yes), the process moves to step S3; if it is determined that the document ejection unit 22 is not full (S2:No), the process moves to step S21.

[0062] <Step S3> In step S3, the first determination processing unit 231 of the control unit 15 determines, based on the detection result by the paper feed detection unit 5, whether the state in which the document Sh1 is placed on the document placement unit 21 has transitioned from a state in which the document Sh1 is placed to a state in which the document Sh1 is not placed. If it is determined that the state in which the document Sh1 is placed on the document placement unit 21 has transitioned from a state in which the document Sh1 is placed to a state in which the document Sh1 is not placed (S3: Yes), the process proceeds to step S5. On the other hand, if it is determined that the state in which the document Sh1 is placed on the document placement unit 21 has not transitioned from a state in which the document Sh1 is placed to a state in which the document Sh1 is not placed (S3: No), the process proceeds to step S4.

[0063] <Step S4> In step S4, the first determination processing unit 231 of the control unit 15 determines, based on the detection result by the paper feed detection unit 5, whether the state has changed from one in which the document Sh1 is not placed on the document placement unit 21 to one in which the document Sh1 is placed. If it is determined that the state has changed from one in which the document Sh1 is not placed on the document placement unit 21 to one in which the document Sh1 is placed (S4:Yes), the process proceeds to step S5. On the other hand, if it is determined that the state has not changed from one in which the document Sh1 is not placed on the document placement unit 21 to one in which the document Sh1 is placed (S4:No), the process returns to step S1.

[0064] <Step S5> In step S5, the lifting / lowering processing unit 234 of the control unit 15 moves the lifting / lowering mechanism 4 upward to move the document placement unit 21 to a preset seventh position, and returns the process to step S1. In this embodiment, the seventh position is the upper limit position. As a result, the space between the document placement unit 21 and the document ejection unit 22 is increased, making it easier for the user to remove the document Sh1 placed on the document ejection unit 22.

[0065] Specifically, the lifting / lowering processing unit 234 determines that the document placement unit 21 has moved to the upper limit position when the output of the upper limit sensor 61 of the position detection unit 6 is "off," and stops the upward movement of the lifting / lowering mechanism 4. In other embodiments, the lifting / lowering processing unit 234 may allow the lifting / lowering mechanism 4 to perform the upward movement for a preset upper limit maximum time, which is the time required for the document placement unit 21 to reach the upper limit position from the lower limit position.

[0066] Furthermore, in this embodiment, the same step S5 is performed when the state changes from one in which the document Sh1 is placed on the document placement section 21 to one in which the document Sh1 is not placed (S3:Yes), and when the state changes from one in which the document Sh1 is not placed on the document placement section 21 to one in which the document Sh1 is placed (S4:Yes).

[0067] On the other hand, in other embodiments, different processing may be performed depending on whether the document Sh1 is placed on the document placement section 21 or not (S3:Yes), or whether the document Sh1 is placed on the document placement section 21 or not (S4:Yes). For example, if the first determination processing section 231 determines that the document placement section 21 has transitioned from a state where the document Sh1 is not placed on it to a state where the document Sh1 is placed on it, the lifting and lowering processing section 234 moves the document placement section 21 to the seventh position using the lifting and lowering mechanism 4. On the other hand, if the first determination processing section 231 determines that the document placement section 21 has transitioned from a state where the document Sh1 is not placed on it to a state where the document Sh1 is placed on it, the lifting and lowering processing section 234 moves the document placement section 21 to a preset eighth position different from the seventh position using the lifting and lowering mechanism 4. The eighth position may be further away from the document output unit 22 than the seventh position, or it may be closer to the document output unit 22 than the seventh position.

[0068] <Step S21> In step S21, the first determination processing unit 231 of the control unit 15 determines, based on the detection result by the paper feed detection unit 5, whether the state has changed from one in which the document Sh1 is placed on the document placement unit 21 to one in which the document Sh1 is not placed. If it is determined that the state has changed from one in which the document Sh1 is placed on the document placement unit 21 to one in which the document Sh1 is not placed (S21:Yes), the process proceeds to step S22. If it is determined that the state has not changed from one in which the document Sh1 is placed on the document placement unit 21 to one in which the document Sh1 is not placed (S21:No), the process proceeds to step S24.

[0069] <Steps S22~S23> In steps S22 to S23, the lifting and lowering processing unit 234 of the control unit 15 moves the lifting and lowering mechanism 4 upward to move the document placement unit 21 to a preset first position, and returns the process to step S1. In this embodiment, the first position is a position lower than the upper limit position by a preset first specified distance. The first position is at least lower than the upper limit position and higher than the lower limit position. This increases the space between the document placement unit 21 and the document output unit 22, making it easier for the user to remove the document Sh1 placed on the document output unit 22. Also, in this embodiment, since the first position is a position lower than the upper limit position by a preset first specified distance, the space above the document placement unit 21 is larger compared to when the document placement unit 21 is at the upper limit position, making it possible to secure space for placing a document on the document placement unit 21.

[0070] Specifically, in this embodiment, in step S22, the lifting / lowering processing unit 234 moves the lifting / lowering mechanism 4 upward, similar to step S5, to move the document placement unit 21 to the upper limit position. Then, in step S23, the lifting / lowering processing unit 234 moves (lowers) the document placement unit 21 to the first position, which is a predetermined first specified distance lower than the upper limit position, and returns the process to step S1. Specifically, if the lifting / lowering processing unit 234 has performed a downward movement by the lifting / lowering mechanism 4 for a predetermined first specified time, it determines that the document placement unit 21 has moved by the first specified distance and stops the downward movement by the lifting / lowering mechanism 4.

[0071] <Step S24> In step S24, the first determination processing unit 231 of the control unit 15 determines, based on the detection result by the paper feed detection unit 5, whether the state has changed from one in which the document Sh1 is not placed on the document placement unit 21 to one in which the document Sh1 is placed. If it is determined that the state has changed from one in which the document Sh1 is not placed on the document placement unit 21 to one in which the document Sh1 is placed (S24:Yes), the process proceeds to step S25. If it is determined that the state has not changed from one in which the document Sh1 is not placed on the document placement unit 21 to one in which the document Sh1 is placed (S24:No), the process returns to step S21.

[0072] <Steps S25~S26> In steps S25 to S26, the lifting / lowering processing unit 234 of the control unit 15 moves the lifting / lowering mechanism 4 upward to move the document placement unit 21 to a preset second position, and returns the process to step S1. In this embodiment, the second position is lower than the upper limit position by a preset second specified distance. The second position is at least lower than the upper limit position and higher than the lower limit position. This increases the space between the document placement unit 21 and the document output unit 22, making it easier for the user to remove the document Sh1 placed on the document output unit 22. Also, in this embodiment, since the second position is lower than the upper limit position by a preset second specified distance, the space above the document placement unit 21 is larger compared to when the document placement unit 21 is at the upper limit position, making it possible to secure space for placing a document on the document placement unit 21. The first position and the second position may be the same position or different positions. For example, the second position may be a position further away from the document ejection unit 22 (a higher position) than the first position.

[0073] Specifically, in this embodiment, in step S25, the lifting / lowering processing unit 234 moves the lifting / lowering mechanism 4 upward, similar to step S5, to move the document placement unit 21 to the upper limit position. Then, in step S26, the lifting / lowering processing unit 234 moves (lowers) the document placement unit 21 to the second position, which is lower by a preset second specified distance from the upper limit position, and returns the process to step S1. Specifically, if the lifting / lowering processing unit 234 has performed a downward movement by the lifting / lowering mechanism 4 for a preset second specified time, it determines that the document placement unit 21 has moved by the second specified distance and stops the downward movement by the lifting / lowering mechanism 4.

[0074] <Step S11> In step S11, the first determination processing unit 231 of the control unit 15 determines, based on the detection result by the paper feed detection unit 5, whether the state in which the document Sh1 is placed on the document placement unit 21 has transitioned from a state in which the document Sh1 is placed to a state in which the document Sh1 is not placed. If it is determined that the state in which the document Sh1 is placed on the document placement unit 21 has transitioned from a state in which the document Sh1 is placed to a state in which the document Sh1 is not placed (S11: Yes), the process proceeds to step S12. On the other hand, if it is determined that the state in which the document Sh1 is placed on the document placement unit 21 has not transitioned from a state in which the document Sh1 is placed to a state in which the document Sh1 is not placed (S11: No), the process proceeds to step S24.

[0075] In other embodiments, in steps S25 to S26, which are performed after moving from step S11 to step S24, the lifting and lowering processing unit 234 may move the document placement unit 21 to a preset sixth position different from the second position. The sixth position is a position lower than the upper limit position by a preset sixth specified distance. The sixth position is at least lower than the upper limit position and higher than the lower limit position. Furthermore, the sixth position is either closer to (lower than) or further away from (higher than) the document ejection unit 22 than the second position.

[0076] <Step S12> In step S12, the lifting / lowering processing unit 234 of the control unit 15 lowers the lifting / lowering mechanism 4 to move the document placement unit 21 to a preset fifth position, and returns the process to step S1. In this embodiment, the fifth position is the lower limit position. This increases the space above the document placement unit 21. As a result, the user can more easily place documents Sh1 on the document placement unit 21, and can place many documents Sh1 on the document placement unit 21.

[0077] Specifically, the lifting / lowering processing unit 234 determines that the document placement unit 21 has moved to the lower limit position when the output of the lower limit sensor 62 of the position detection unit 6 is "off," and stops the lowering operation of the lifting / lowering mechanism 4. In other embodiments, the lifting / lowering processing unit 234 may perform the lower limit operation of the lifting / lowering mechanism 4 for a predetermined maximum time required for the document placement unit 21 to reach the lower limit position from the upper limit position.

[0078] [Second Lifting Control Process] The second lifting and lowering control process performed by the control unit 15 in the image processing apparatus 1 according to this embodiment will now be described with reference to Figure 5. The second lifting and lowering control process is performed when the specific job accompanied by the automatic image reading process is completed.

[0079] Here, steps S31, S32, etc. in Figure 5 represent the processing procedure (step) numbers executed by the control unit 15. The control unit 15 mainly consists of a computer system having one or more processors and one or more memories, and the following processing is realized when one or more processors execute a control program.

[0080] Furthermore, the procedures for the first and second lifting control processes are merely examples, and the order of the processes shown in the flowcharts of Figures 4 and 5 may be rearranged as appropriate, and processes may be added or omitted. For example, in this embodiment, since the original document Sh1 is ejected to the document ejection unit 22 at the end of the automatic image reading process, the second lifting control process assumes that the original document Sh1 is placed on the document ejection unit 22. On the other hand, in the second lifting control process, it may be determined whether or not the original document Sh1 is placed on the document ejection unit 22 based on the detection result of the paper ejection detection unit 7, and if the original document Sh1 is placed on the document ejection unit 22, step S31 described later may be executed.

[0081] <Step S31> In step S31, the third determination processing unit 233 of the control unit 15 determines whether the document ejection unit 22 is full or not, similar to step S2. If it is determined that the document ejection unit 22 is full (S31: Yes), the process proceeds to step S32. If it is determined that the document ejection unit 22 is not full (S31: No), the process proceeds to step S33.

[0082] <Step S32> In step S32, the lifting / lowering processing unit 234 of the control unit 15 moves the lifting / lowering mechanism 4 upward, similar to step S5, to move the document placement unit 21 to the seventh position, and terminates the second lifting / lowering control process.

[0083] <Step S33> In step S33, the lifting / lowering processing unit 234 of the control unit 15 determines whether or not a document is placed on the document placement unit 21 based on the detection result by the paper feed detection unit 5. If it is determined that a document is placed on the document placement unit 21 (S33: Yes), the process proceeds to step S34. If it is determined that no document is placed on the document placement unit 21 (S33: No), the process proceeds to step S36.

[0084] <Steps S34-S35> In steps S34 to S35, the lifting and lowering processing unit 234 of the control unit 15 moves the lifting and lowering mechanism 4 upward to move the document placement unit 21 to a preset fourth position, and returns the process to step S1. In this embodiment, the fourth position is lower than the upper limit position by a preset fourth specified distance. The fourth position is at least lower than the upper limit position and higher than the lower limit position. This increases the space between the document placement unit 21 and the document output unit 22, making it easier for the user to remove the document Sh1 placed on the document output unit 22. Also, in this embodiment, since the fourth position is lower than the upper limit position by a preset fourth specified distance, the space above the document placement unit 21 is larger compared to when the document placement unit 21 is at the upper limit position, making it possible to secure space for placing a document on the document placement unit 21.

[0085] Specifically, in this embodiment, in step S34, the lifting / lowering processing unit 234 moves the lifting / lowering mechanism 4 upward, similar to step S5, to move the document placement section 21 to the upper limit position. Then, in step S35, the lifting / lowering processing unit 234 moves (lowers) the document placement section 21 to the fourth position, which is a predetermined fourth specified distance lower than the upper limit position, and terminates the second lifting / lowering control process. Specifically, if the lifting / lowering processing unit 234 has performed a downward movement by the lifting / lowering mechanism 4 for a predetermined fourth specified time, it determines that the document placement section 21 has moved by the fourth specified distance and stops the downward movement by the lifting / lowering mechanism 4.

[0086] In this embodiment, the second and fourth specified distances are the same, and the second and fourth positions are the same. On the other hand, in other embodiments, the second and fourth specified distances may be different, and the second and fourth positions may be different. For example, when the automatic image reading process for reading an image from the document Sh1 is completed, if the first determination processing unit 231 determines that the document Sh1 is placed on the document placement unit 21, the automatic image reading process for the document Sh1 may continue to be executed. For this reason, the fourth position may be further from the document ejection unit 22 than the second position. This makes it possible for the image processing device 1 to quickly start the automatic image reading process for the document Sh1 placed on the document placement unit 21.

[0087] <Steps S36-S37> In steps S36 to S37, the lifting and lowering processing unit 234 of the control unit 15 moves the lifting and lowering mechanism 4 upward to move the document placement unit 21 to a preset third position, and returns the process to step S1. In this embodiment, the third position is lower than the upper limit position by a preset third specified distance. The third position is at least lower than the upper limit position and higher than the lower limit position. This increases the space between the document placement unit 21 and the document output unit 22, making it easier for the user to remove the document Sh1 placed on the document output unit 22. In addition, in this embodiment, the fourth position is lower than the upper limit position by a preset fourth specified distance, so the space above the document placement unit 21 is larger compared to when the document placement unit 21 is at the upper limit position, making it possible to secure space for placing a document on the document placement unit 21.

[0088] Specifically, in this embodiment, in step S36, the lifting / lowering processing unit 234 moves the lifting / lowering mechanism 4 upward, similar to step S5, to move the document placement section 21 to the upper limit position. Then, in step S37, the lifting / lowering processing unit 234 moves (lowers) the document placement section 21 to the third position, which is a predetermined third specified distance lower than the upper limit position, and terminates the second lifting / lowering control process. Specifically, if the lifting / lowering processing unit 234 has performed a downward movement by the lifting / lowering mechanism 4 for a predetermined third specified time, it determines that the document placement section 21 has moved by the third specified distance and stops the downward movement by the lifting / lowering mechanism 4.

[0089] In this embodiment, the first specified distance and the third specified distance are the same, and the first position and the third position are the same. On the other hand, in other embodiments, the first specified distance and the third specified distance may be different, and the first position and the third position may be different. For example, when the automatic image reading process for reading an image from the document Sh1 is completed, if the first judgment processing unit 231 determines that the document Sh1 is not placed on the document placement unit 21, it is highly likely that the automatic image reading process for the document Sh1 will not continue to be executed. For this reason, the third position may be a position further away from the document discharge unit 22 (a higher position) than the first position. This makes it easier to remove the document Sh1 placed on the document discharge unit 22.

[0090] As described above, in the image processing apparatus 1 according to this embodiment, the raising and lowering of the document placement section 21 is controlled based on the determination results of the first determination processing section 231 and the second determination processing section 232, which use at least the document placement section 21 and the document ejection section 22. Therefore, the image processing apparatus 1 can achieve a good balance between ease of removing documents from the document ejection section and securing space for placing documents in the document placement section.

[0091] The first to eighth positions described in this embodiment are merely examples and can be set arbitrarily in advance. In particular, the heights of the first to fourth positions may be in the relationship first position < second position < third position < fourth position (with the first position being the lowest and the fourth position being the highest). The control unit 15 may also be able to arbitrarily change the first to eighth positions in response to user operation. Furthermore, the control unit 15 may also be able to change whether or not to execute one or more of the various lifting operations in the first lifting control process and the second lifting control process in response to user operation.

[0092] In this embodiment, the case in which the document placement section 21 is raised and lowered (position controlled) according to the presence or absence of document Sh1 in the document placement section 21, the presence or absence of document Sh1 in the document discharge section 22, and the full load status of the document discharge section 22 has been described. On the other hand, in other embodiments, the document placement section 21 may be raised and lowered (position controlled) according to one or more of the presence or absence of document Sh1 in the document placement section 21, the presence or absence of document Sh1 in the document discharge section 22, and the full load status of the document discharge section 22. For example, in other embodiments, the document placement section 21 may be raised and lowered (position controlled) according to the presence or absence of document Sh1 in the document placement section 21 and the presence or absence of document Sh1 in the document discharge section 22. In this case, steps S2, S21-S23 in the first raising and lowering control process in Figure 4 and steps S31-S32 in the second raising and lowering control process in Figure 5 are omitted. Furthermore, either steps S2, S21-S23 in the first lifting control process in Figure 4 or steps S31-S32 in the second lifting control process in Figure 5 may be omitted.

[0093] Furthermore, in this embodiment, a case has been described in which the position of the document placement section 12 is controlled by the execution time of the downward movement of the lifting mechanism 4 from the upper limit position (e.g., first specified time to fourth specified time). In other embodiments, a detection unit (not shown), such as an optical sensor, ultrasonic sensor, or contact sensor, may be provided to detect when the document placement section 21 has reached the first to eighth positions, respectively. In this case, the lifting processing unit 234 may control the lifting mechanism 4 based on the detection result of the detection unit (not shown) in the first lifting control process and the second lifting control process, and control the position of the document placement section 21.

[0094] [Notes on the invention] The following is an overview of the invention extracted from the above-described embodiments. Note that each configuration and processing function described below can be selected and combined as desired.

[0095] <Note 1> A transport mechanism that sequentially transports a document placed on a document placement section to a document discharge section located below the document placement section, through an image reading position where an image is read from the document. A lifting mechanism for raising and lowering the document placement section, A first determination processing unit that determines whether or not a document is placed in the document placement unit, A second determination processing unit that determines whether or not a document is placed in the document ejection unit, A lifting and lowering processing unit controls the lifting and lowering operation of the lifting and lowering mechanism based on the determination results of the first and second determination processing units, A document transport device equipped with the following features.

[0096] <Note 2> The lifting and lowering processing unit moves the document placement unit to a preset first position using the lifting and lowering mechanism when the second determination processing unit determines that the document is placed on the document ejection unit, and the first determination processing unit determines that the document placement unit has transitioned from a state where the document is placed to a state where the document is not placed. The document transport device described in Appendix 1.

[0097] <Note 3> The lifting and lowering processing unit moves the document placement unit to a preset second position using the lifting and lowering mechanism when the second determination processing unit determines that the document is placed on the document ejection unit, and the first determination processing unit determines that the document placement unit has transitioned from a state where the document is not placed to a state where the document is placed. The document transport device described in Appendix 1 or 2.

[0098] <Note 4> When the image reading process for reading an image from the original document is completed, if the first determination processing unit determines that the original document is not placed on the original document placement unit, the lifting and lowering mechanism moves the original document placement unit to a predetermined third position. A document transport device as described in any of the appendices 1 to 3.

[0099] <Note 5> When the image reading process for reading an image from the original document is completed, the lifting and lowering processing unit, if the first determination processing unit determines that the original document is placed on the original document placement unit, moves the original document placement unit to a predetermined fourth position using the lifting and lowering mechanism. A document transport device as described in any of the appendices 1 to 4.

[0100] <Note 6> The lifting and lowering processing unit moves the document placement unit to a preset fifth position using the lifting and lowering mechanism when the second determination processing unit determines that no document is placed on the document ejection unit, and the first determination processing unit determines that the document placement unit has transitioned from a state where a document is placed on it to a state where no document is placed on it. A document transport device as described in any of the appendices 1 to 5.

[0101] <Note 7> The lifting and lowering processing unit moves the document placement unit to a preset sixth position using the lifting and lowering mechanism when the second determination processing unit determines that no document is placed on the document ejection unit, and the first determination processing unit determines that the document placement unit has transitioned from a state where no document is placed on it to a state where a document is placed on it. A document transport device as described in any of the appendices 1 to 6.

[0102] <Note 8> The system further includes a third determination processing unit that determines whether the amount of documents placed on the document output unit has reached a predetermined specific amount. When the third determination processing unit determines that the amount of documents placed on the document ejection unit has reached the specified amount, and the first determination processing unit determines that the document placement unit has transitioned from a state in which documents are placed to a state in which documents are not placed, the lifting and lowering mechanism moves the document placement unit to a preset seventh position. A document transport device as described in any of the appendices 1 to 7.

[0103] <Note 9> The system further includes a third determination processing unit that determines whether the amount of documents placed on the document output unit has reached a predetermined specific amount. The lifting and lowering processing unit moves the document placement unit to a preset eighth position using the lifting and lowering mechanism when the third determination processing unit determines that the amount of documents placed on the document output unit has reached the specified amount, and the first determination processing unit determines that the document placement unit has transitioned from a state where no documents are placed on it to a state where documents are placed on it. A document transport device as described in any of the appendices 1 to 8.

[0104] <Note 10> A document transport device as described in any of the appendices 1 to 9, An image reading unit that reads an image from a document transported by the aforementioned document transport device, An image processing device equipped with the following features.

[0105] <Note 11> A document transport device comprising a transport mechanism that sequentially transports a document placed on a document placement section to a document discharge section located below the document placement section, through an image reading position where an image is read from the document, and a lifting mechanism that raises and lowers the document placement section, is controlled by one or more processors. The first step is to determine whether or not a document is placed in the document placement section, A second step is to determine whether or not a document is placed in the document output section, A third step involves controlling the lifting operation of the lifting mechanism based on the determination results of the first and second steps, A method for transporting documents. [Explanation of symbols]

[0106] 1 Image Processing Device 2. Document transport device 3. Conveying mechanism 4. Lifting mechanism 5. Paper feed detection unit 6 Position detection unit 7 Paper ejection detection unit 8. Full load detection unit 11 Image reading unit 12 Image forming unit 21 Manuscript Placement Section 22 Original output section 231 First Decision Processing Unit 232 Second Decision Processing Unit 233 Third Decision Processing Unit 234 Lifting and lowering section Sh1 manuscript

Claims

1. A transport mechanism that sequentially transports a document placed on a document placement section to a document discharge section located below the document placement section, through an image reading position where an image is read from the document. A lifting mechanism for raising and lowering the document placement section, A first determination processing unit that determines whether or not a document is placed in the document placement unit, A second determination processing unit that determines whether or not a document is placed in the document ejection unit, A lifting and lowering processing unit controls the lifting and lowering operation of the lifting and lowering mechanism based on the determination results of the first and second determination processing units, A document transport device equipped with the following features.

2. The lifting and lowering processing unit moves the document placement unit to a preset first position using the lifting and lowering mechanism when the second determination processing unit determines that the document is placed on the document ejection unit, and the first determination processing unit determines that the document placement unit has transitioned from a state where the document is placed to a state where the document is not placed. The document transport device according to claim 1.

3. When the second determination processing unit determines that a document is placed on the document ejection unit, and the first determination processing unit determines that the document has transitioned from a state where no document is placed on the document placement unit to a state where a document is placed, the lifting and lowering mechanism moves the document placement unit to a preset second position. The document transport device according to claim 1.

4. When the image reading process for reading an image from the original document is completed, if the first determination processing unit determines that the original document is not placed on the original document placement unit, the lifting and lowering unit moves the original document placement unit to a predetermined third position using the lifting and lowering mechanism. A document transport device according to any one of claims 1 to 3.

5. When the image reading process for reading an image from the original document is completed, the lifting and lowering processing unit, if the first determination processing unit determines that the original document is placed on the original document placement unit, moves the original document placement unit to a predetermined fourth position using the lifting and lowering mechanism. A document transport device according to any one of claims 1 to 3.

6. The lifting and lowering processing unit moves the document placement unit to a preset fifth position using the lifting and lowering mechanism when the second determination processing unit determines that no document is placed on the document ejection unit, and the first determination processing unit determines that the document placement unit has transitioned from a state where a document is placed on it to a state where no document is placed on it. The document transport device according to claim 1.

7. The lifting and lowering processing unit moves the document placement unit to a preset sixth position using the lifting and lowering mechanism when the second determination processing unit determines that no document is placed on the document ejection unit, and the first determination processing unit determines that the document placement unit has transitioned from a state where no document is placed on it to a state where a document is placed on it. The document transport device according to claim 1.

8. The system further includes a third determination processing unit that determines whether the amount of documents placed on the document output unit has reached a predetermined specific amount. The lifting and lowering processing unit moves the document placement unit to a preset seventh position using the lifting and lowering mechanism when the third determination processing unit determines that the amount of documents placed on the document output unit has reached the specified amount, and the first determination processing unit determines that the document placement unit has transitioned from a state where documents are placed on it to a state where documents are not placed on it. A document transport device according to any one of claims 1 to 3.

9. The system further includes a third determination processing unit that determines whether the amount of documents placed on the document output unit has reached a predetermined specific amount. The lifting and lowering processing unit moves the document placement unit to a preset eighth position using the lifting and lowering mechanism when the third determination processing unit determines that the amount of documents placed on the document ejection unit has reached the specified amount, and the first determination processing unit determines that the document placement unit has transitioned from a state where no documents are placed on it to a state where documents are placed on it. A document transport device according to any one of claims 1 to 3.

10. A document transport device according to any one of claims 1 to 3, An image reading unit that reads an image from a document transported by the aforementioned document transport device, An image processing device equipped with the following features.

11. A document transport device comprising a transport mechanism that sequentially transports a document placed on a document placement section to a document discharge section located below the document placement section, through an image reading position where an image is read from the document, and a lifting mechanism that raises and lowers the document placement section, is controlled by one or more processors. The first step is to determine whether or not a document is placed in the document placement section, A second step is to determine whether or not a document is placed in the document output section, A third step involves controlling the lifting operation of the lifting mechanism based on the determination results of the first and second steps, A method for transporting documents.

Images