Document conveyance device

Abstract

To provide a document conveyance device capable of easily and safely stopping a conveyance of an erroneous document while preventing paper jam and damage to a paper feed roller in the document conveyance device.SOLUTION: A document conveyance device includes: a feed roller that supplies a document to a conveyance path; a feed tray on which the document can be placed; a size sensor that detects a size of the document on the feed tray; a lifting part that lifts the feed tray to bring the document on the feed tray into contact with the feed roller; and a control part that controls the lifting part based on a detection signal from the size sensor. The control part controls the lifting part to lower the paper feed tray when the size sensor detects that the size of the document is about to be changed while the lifting part is in contact with a paper feed roller with the document on the paper feed tray.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] The present disclosure relates to a document conveying device.

Background Art

[0002] In recent years, as disclosed in Patent Document 1, development of a document conveying device mounted on an image forming apparatus has been carried out. Such a document conveying device generally raises or lowers a paper feed tray based on a user's operation on an operation panel.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the document conveying device as described above, with the document placed on the paper feed tray, the paper feed tray rises by a user's panel operation. After the paper feed tray has risen, there may be a case where the user wants to remove a document accidentally placed on the paper feed tray from the paper feed tray. In this case, if the user pulls out the document sandwiched between the paper feed roller and the paper feed tray, there is a problem that the paper feed tray and the document may be damaged. This problem also occurs similarly in a document conveying device in which the paper feed roller descends toward the paper feed tray to sandwich the document between the paper feed roller and the paper feed tray.

[0005] The present disclosure has been made in view of the above problems. An object of the present disclosure is to provide a document conveying device capable of suppressing damage to the paper feed roller and the document.

Means for Solving the Problems

[0006] The document feeding device according to the first aspect of the present disclosure includes a paper feeding roller that supplies a document to a conveyance path, a paper feeding tray on which the document can be placed, a size sensor that detects the size of the document on the paper feeding tray, a lifting / lowering unit that contacts the paper feeding roller with the document on the paper feeding tray by raising the paper feeding tray, and a control unit that controls the lifting / lowering unit based on a detection signal of the size sensor. The control unit controls the lifting / lowering unit to lower the paper feeding tray when the size sensor detects that the size of the document is about to be changed while the lifting / lowering unit is in a state of contacting the paper feeding roller with the document on the paper feeding tray.

[0007] The document feeding device according to the second aspect of the present disclosure includes a paper feeding roller that supplies a document to a conveyance path, a paper feeding tray on which the document can be placed, a size sensor that detects the size of the document on the paper feeding tray, a lifting / lowering unit that contacts the paper feeding roller with the document on the paper feeding tray by lowering the paper feeding roller, and a control unit that controls the lifting / lowering unit based on a detection signal of the size sensor. The control unit controls the lifting / lowering unit to raise the paper feeding roller when the size sensor detects that the size of the document is about to be changed while the lifting / lowering unit is in a state of contacting the paper feeding roller with the document on the paper feeding tray.

Brief Description of the Drawings

[0008]

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Mode for Carrying Out the Invention

[0009] Hereinafter, the document conveyance device according to the embodiment of the present disclosure will be described with reference to the drawings. Regarding the drawings, the same or equivalent elements are denoted by the same reference numerals, and duplicate explanations will not be repeated.

[0010] (First Embodiment) The document conveyance device 100 according to the first embodiment will be described with reference to FIGS. 1 to 15. The document conveyance device 100 according to the present embodiment constitutes a part of the image forming apparatus.

[0011] FIG. 1 is a perspective view of the document conveyance device 100 according to the present embodiment. FIG. 2 is a perspective view showing a state in which the cover 102 of the document conveyance device 100 according to the present embodiment is opened.

[0012] As shown in FIGS. 1 and 2, the document feeding device 100 is mounted on an image reading device (scanner) above an image forming apparatus main body 1000 having an operation unit 6 operated by a user, and is mounted on the image forming apparatus main body 1000 so as to be openable and closable. The document feeding device 100 includes a main body 101 and a cover 102 provided on the main body 101 so as to be openable and closable. The operation unit 6 includes a touch panel and switches operable by the user. The operation unit 6 is for causing the document feeding device 100 to execute various functions described below.

[0013] When the cover 102 is opened from the main body 101, it is understood that the paper feed tray 1 and the paper feed roller 21 are provided so as to face each other. In the present embodiment, the paper feed tray 1 is configured to move in the vertical direction, and the paper feed roller 21 is fixed to the main body 101. The paper feed tray 1 is provided with a guide unit 11 including a pair of guide members 11a and 11b for guiding the document.

[0014] FIG. 3 is a cross-sectional view of the document feeding device 100 of the present embodiment. FIG. 4 is a functional block diagram showing the overall configuration of the document feeding device 100 of the present embodiment.

[0015] As shown in FIGS. 3 and 4, the document feeding device 100 of the present embodiment includes a paper feed tray 1, a paper feeding unit 2, a conveying unit 3, a lifting unit 4, a control unit 5, an operation unit 6, a size sensor 7, a stacking tray 8, and a guide unit 11. The document feeding device 100 of the present embodiment includes a paper feed tray upper limit detection sensor 71, a paper feed tray lower limit detection sensor 72, and a cover sensor 73 as other sensors different from the size sensor 7.

[0016] The paper feed tray 1 is configured such that a document can be placed thereon. The paper feed tray 1 is raised or lowered in the direction indicated by the arrow in FIG. 3 by the lifting unit 4. When the paper feed tray 1 is raised by the lifting unit 4 with a document placed thereon, the document is brought into contact with the paper feed roller 21. The paper feed tray 1 is provided with a guide unit 11 and a size sensor 7.

[0017] The paper feeding unit 2 has a paper feeding roller 21 and a paper feeding motor 22. The paper feeding roller 21 rotates by the rotation of the paper feeding motor 22. The paper feeding motor 22 rotates or stops by being controlled by the control unit 5. In a state where the paper feeding tray 1 is raised, the paper feeding tray 1 and the paper feeding roller 21 sandwich the document placed on the paper feeding tray 1. In this state, when the paper feeding motor 22 rotates the paper feeding roller 21, the document is supplied to the conveyance path 30 by the paper feeding roller 21.

[0018] The conveyance unit 3 includes a plurality of conveyance rollers 31, 32, 33, 34, 35, 36, 37. The conveyance path 30 is formed so as to connect the positions between the opposing rollers of the plurality of conveyance rollers 31, 32, 33, 34, 35, 36, 37. Among the conveyance unit 3, only the plurality of conveyance rollers 31 rotate when the paper feeding motor 22 rotates, because the rotation of the paper feeding motor 22 is transmitted through a belt. Further, the conveyance unit 3 includes a conveyance motor 38 that rotates each of the plurality of conveyance rollers 32, 33, 34, 35, 36, 37 other than the plurality of conveyance rollers 31. The rotation motion of a specific conveyance roller among the plurality of conveyance rollers 32, 33, 34, 35, 36, 37 is transmitted directly or through a belt by the conveyance motor 38. The conveyance rollers other than the specific rollers among the plurality of conveyance rollers 32, 33, 34, 35, 36, 37 rotate following the rotation of the opposing conveyance rollers.

[0019] The document supplied to the plurality of conveyance rollers 31 that rotate together with the paper feeding roller 21 by the rotation of the paper feeding roller 21 is conveyed along the conveyance path 30 by the rotation of each of the plurality of conveyance rollers 32, 33, 34, 35, 36, 37 due to the drive of the conveyance motor 38. After the document is conveyed along the conveyance path 30, it is sent out from the conveyance path 30 onto the stacking tray 8.

[0020] The lifting section 4 has a lifting mechanism 41 and a lifting motor 42. The lifting mechanism 41 is configured to lift or lower the paper feed tray 1 in the direction indicated by the arrow. The lifting motor 42 is driven to lift or lower the lifting mechanism 41 under the control of the control unit 5. When the lifting mechanism 41 lifts the paper feed tray 1, the document placed on the paper feed tray 1 comes into contact with the paper feed roller 21. As a result, the document placed on the paper feed tray 1 is sandwiched between the paper feed tray 1 and the paper feed roller 21.

[0021] The control unit 5 is called a controller. As shown in FIG. 4, the control unit 5 includes a memory M and a processor P that executes a program stored in the memory M. The processor P receives a command signal from the operation unit 6. Also, the processor P receives detection signals from the size sensors 7 (7a, 7b(1), 7b(2), 7b(3)) and other sensors 70 (71, 72, 73). Thereby, the processor P controls the paper feed motor 22, the conveyance motor 38, the lifting motor 42, etc. based on the command signal or the detection signal.

[0022] The operation unit 6 is a user interface generally called a touch panel. The operation unit 6 is constituted by, for example, a liquid crystal display panel. The operation unit 6 transmits a command signal to the control unit 5 described later by touching an operation icon displayed on the liquid crystal display panel. For example, the user can transmit a command signal that can specify a print-related job to the control unit 5 by operating the operation unit 6.

[0023] The size sensor 7 includes a guide width detection sensor 7a, original document length sensors 7b(1) and 7b(2), and an original document detection sensor 7b(3). The guide width detection sensor 7a is a sensor for detecting that the width between the guide member 11a and the guide member 11b has changed by a predetermined value, for example, 10 mm or more. The original document length sensors 7b(1) and 7b(2) are sensors for detecting a change in the length in the advancing direction of the original document placed on the paper feed tray 1. The original document detection sensor 7b(3) is a sensor for detecting the presence or absence of an original document on the paper feed tray 1 (whether the original document length is 0).

[0024] The other sensor 70 includes a paper feed tray upper limit detection sensor 71, a paper feed tray lower limit detection sensor 72, and a cover sensor 73. The paper feed tray upper limit detection sensor 71 detects that the paper feed tray 1 has been raised to the upper limit and transmits the detection signal to the control unit 5. The paper feed tray lower limit detection sensor 72 detects that the paper feed tray 1 has been lowered to the lower limit and transmits the detection signal to the control unit 5. The cover sensor 73 detects that the cover 102 has been opened and transmits the detection signal to the control unit 5.

[0025] Next, with reference to FIGS. 5 to 9, the main points of a series of operations of the original document conveyance device 100 of the present embodiment will be described.

[0026] FIG. 5 is a schematic plan view of the original document conveyance device 100 of the present embodiment, showing a state in which the user's hand is moving the guide members 11a and 11b after the paper feed tray 1 has been raised and before the original document is supplied to the conveyance path by the paper feed roller 21.

[0027] Before the original document P(1) is supplied to the conveyance path 30 by the rotation of the paper feed roller 21, the user H may notice that the original document P(1) is different from the original document that should originally be supplied to the conveyance path 30. In this case, as shown in FIG. 5, the user H moves the pair of guide members 11a and 11b in the direction indicated by the white arrow by hand in order to avoid the supply of the original document P(1) to the conveyance path 30 by the paper feed roller 21.

[0028] Accordingly, when the guide width detection sensor 7a detects that the width between the guide member 11a and the guide member 11b has changed by a predetermined amount or more, the detection signal is transmitted to the control unit 5. As a result, the control unit 5 lowers the paper feed tray 1.

[0029] FIG. 6 is a schematic cross-sectional view of the document conveying apparatus 100 according to the present embodiment, showing a state in which the document P(1) is being supplied to the conveyance path 30 by the paper feed roller 21 after the paper feed tray 1 has been raised.

[0030] As shown in FIG. 6, for example, two documents P(1) and P(2) are stacked and placed on the paper feed tray 1. Thereafter, when the control unit 5 receives a command signal to start a print job from the operation unit 6 by an operation of the user on the operation unit 6, the control unit 5 starts the conveyance of the documents P(1) and P(2) by the document conveying apparatus 100. Note that the command signal is not limited to one for starting a print job, and may be a command signal for any job.

[0031] In this case, the control unit 5 first drives the lifting motor 42 to cause the lifting mechanism 41 to raise the paper feed tray 1. Thereby, the documents P(1) and P(2) are sandwiched between the paper feed tray 1 and the paper feed roller 21. At this time, the upper document P(1) of the documents P(1) and P(2) comes into contact with the paper feed roller 21.

[0032] Thereafter, the control unit 5 rotates the paper feed motor 22 and the conveyance motor 38 respectively to start the rotation of the paper feed roller 21 and the conveyance rollers 31, 32, 33, 34, 35, 36, 37. As a result, the document P(1) is supplied to the conveyance path 30 by the rotation of the paper feed roller 21. Thereafter, the conveyance of the document P(1) in the conveyance path 30 is started by the rotation of the conveyance rollers 31, 32, 33, 34, 35, 36, 37.

[0033] FIG. 7 is a schematic plan view of the document conveying apparatus 100 according to the present embodiment, showing a state in which the hand of the user H is moving the guide members 11a and 11b.

[0034] As shown in FIG. 7, the document P(1) is supplied to the conveyance path 30 by the rotation of the paper feed roller 21. At this time, the user H may notice that the documents P(1) and P(2) actually supplied to the conveyance path 30 are different from the documents that should originally be supplied to the conveyance path 30. In this case, in order to avoid the supply of the additional document P(2) to the conveyance path 30 by the paper feed roller 21, the user H manually moves the pair of guide members 11a and 11b in the direction indicated by the white arrow.

[0035] Thereby, when the guide width detection sensor 7a detects that the width between the guide member 11a and the guide member 11b has changed by a predetermined amount or more, it transmits the detection signal to the control unit 5. As a result, the control unit 5 stops the rotation of the paper feed roller 21 by the paper feed motor 22. Thereby, further supply of the document P(2) to the conveyance path 30 by the paper feed roller 21 is not performed.

[0036] FIG. 8 is a schematic cross-sectional view of the document conveyance device 100 according to the present embodiment, and shows a state until the conveyance of the document P(1) already supplied to the conveyance path 30 by the plurality of conveyance rollers 31, 32, 33, 34, 35, 36, 37 is completed after the paper feed roller 21 is stopped.

[0037] As shown in FIG. 8, even when the guide width detection sensor 7a detects that the width of the pair of guide members 11a and 11b has changed by a predetermined amount or more, the control unit 5 continues the rotation of the conveyance motor 38. Thereby, the conveyance of the document P(1) by the plurality of conveyance rollers 32, 33, 34, 35, 36, 37 is continued until the document P(1) already supplied to the conveyance path 30 is sent out onto the stacking tray 8 from the conveyance path 30. However, at this time, the control unit 5 has already stopped the paper feed motor 22 to stop the further supply of the document P(2) to the conveyance path 30 by the paper feed roller 21.

[0038] FIG. 9 is a schematic cross-sectional view of the document transport device 100 according to the first embodiment, showing a state in which the printing job has been stopped after the paper feed tray 1 has been lowered. Note that the document transport device 100 may be configured such that the paper feed tray is lowered after the printing job has been stopped. Also, the job in this case is not limited to a printing job and may be any type of job.

[0039] As shown in FIG. 9, a document P(1) is sent out from the transport path 30 onto the stacking tray 8 by a plurality of transport rollers 31, 32, 33, 34, 35, 36, 37. That is, even when the width between the pair of guide members 11a, 11b is changed by a user H by a predetermined amount or more, the transport of the document P(1) being transported is completed. Thereafter, the control unit 5 drives the lifting motor 42 to lower the paper feed tray 1 to the lifting mechanism 41 as indicated by the arrow. At this time, the document P(2) is in a state of being placed on the paper feed tray 1. Thereafter, the control unit 5 completely stops the printing job (however, the job may be a job other than the printing job) based on the operation of the user's operation unit 6.

[0040] According to the control of the control unit 5 described above, it is possible to prevent the start of a new transport of an incorrect document P while suppressing the occurrence of a problem that the document P remains in the transport path 30. As a result, even after the user notices the supply of the incorrect document P to the transport path 30, it is possible to suppress the occurrence of a problem that the document P continues to be supplied to the transport path 30 while preventing the document P from jamming in the transport path 30.

[0041] FIG. 10 is a schematic cross-sectional view of the document transport device 100 according to the present embodiment, showing a state in which the presence of the user H's hand is detected by the size sensor 7.

[0042] As shown in FIG. 10, the second example of the size sensor 7 is a document length sensor 7b(1) that detects the length of the document P(2) in the advancing direction of the document P(2) placed on the paper feed tray 1. When the lifting / lowering unit 4 is in contact with the document P(2) on the paper feed tray 1 and the paper feed roller 21, the document length sensor 7b(1) may detect that the length of the document P(2) placed on the paper feed tray 1 has become longer. Also in this case, the control unit 5 assumes that it has been detected that the size of the document P(2) is about to be changed by the size sensor 7.

[0043] Specifically, it may be detected by the document length sensor 7b(1) that the hand of the user H is touching the end of the document P, for example, that the document length sensor 7b(1) has turned ON. In this case, the control unit 5 assumes that it has been detected that the size of the document P is about to be changed by the size sensor 7. Thereby, when the user's hand is touching the rear end of the document P(2) in the advancing direction, the paper feed tray 1 can be automatically lowered.

[0044] Also in the case of this second example, the control unit 5 uses the document length sensor 7b(1) generally used in the document conveying device 100 to lower the paper feed tray 1. Therefore, the number of parts of the document conveying device 100 does not increase.

[0045] FIG. 11 is a schematic cross-sectional view of the document conveying device 100 of the present embodiment, showing a state in which it is detected by the size sensor 7 that the end of the document P has been lifted by the hand of the user H.

[0046] As shown in FIG. 11, a third example of the size sensor 7 is a document length sensor 7b(2) that detects the length of the document P in the advancing direction of the document P placed on the paper feed tray 1. In the present embodiment, when the lifting / lowering unit 4 contacts the document P(2) on the paper feed tray 1 with the paper feed roller 21, the document length sensor 7b(2) may detect that the length of the document P(2) placed on the paper feed tray 1 has become shorter. Even in this case, the control unit 5 assumes that it has been detected by the size sensor 7 that the size of the document P is about to be changed.

[0047] Specifically, when it is detected by the document length sensor 7b(2) that the user H's hand is trying to lift the end of the document P, for example, when it is detected that the document length sensor 7b(2) has turned OFF. In this case, the control unit 5 assumes that it has been detected by the size sensor 7 that the size of the document P is about to be changed.

[0048] According to the above-described document conveying apparatus 100, when the rear end portion of the document P in the advancing direction is lifted by the user, the paper feed tray 1 can be automatically lowered.

[0049] Further, the control unit 5 uses the document length sensor 7b(2) generally used in the document conveying apparatus 100 to lower the paper feed tray 1. Therefore, the number of parts of the document conveying apparatus 100 does not increase.

[0050] FIGS. 12 to 14 are first to third flowcharts for explaining the processing executed by the control unit 5 of the document conveying apparatus 100 of the present embodiment before conveying the document.

[0051] As shown in FIG. 12, in step S1, the control unit 5 determines whether or not the cover 102 is closed based on the detection signal of the cover sensor 73. If it is determined in step S1 that the cover 102 is not closed, then in step S2, the control unit 5 determines whether or not the cover 102 has changed to a closed state.

[0052] In step S2, if the cover 102 has not changed to the closed state, the control unit 5 repeatedly executes the processes of steps S1 and S2. On the other hand, in step S2, if the cover 102 has changed to the closed state, the control unit 5, in step S3, after executing control to lower the paper feed tray 1, executes the process of step S1 again.

[0053] In step S1, if the cover 102 is closed, in step S5, the control unit 5 determines whether or not there is an original on the paper feed tray 1. In step S5, if it is determined that there is no original on the paper feed tray 1, the process of step S1 is executed. In step S5, if it is determined that there is an original on the paper feed tray 1, in step S6, the control unit 5 determines whether or not the paper feed tray 1 has changed to a state where no original is placed thereon based on the detection signal of the original by the original detection sensor 7b(3).

[0054] In step S6, if it is determined that the paper feed tray 1 has changed to a state where no original is placed thereon, the control unit 5, in step S3, after executing control to lower the paper feed tray 1 to the elevating unit 4, executes the process of step S1 again. In step S6, there may be a case where it is determined that the paper feed tray 1 has not changed to a state where no original is placed thereon. In this case, the control unit 5, in step S7, determines whether or not the paper feed tray 1 has been moved to the upper limit position based on whether or not the paper feed tray upper limit detection sensor 71 is ON.

[0055] In step S7, it may be determined that the paper feed tray 1 has been moved to the upper limit position. In this case, the control unit 5 executes control to determine whether to lower the paper feed tray 1 in step S8 (the paper feed tray lowering determination control in S8 is S11 to S15 in FIG. 13). In step S7, it may be determined that the paper feed tray 1 is not in the state of being moved to the upper limit position. In this case, the control unit 5 determines in step S9 whether there has been an operation to start a print job (this may also be a job other than a print job) on the operation unit 6 by the user, that is, whether a job start request signal has been transmitted from the operation unit 6.

[0056] If it is determined in step S9 that a job start request signal has not been transmitted from the operation unit 6, the control unit 5 executes the process of step S1 again. If it is determined in step S9 that a job start request signal has been transmitted from the operation unit 6, the control unit 5 raises the paper feed tray 1 in step S10.

[0057] As shown in FIG. 13, in the paper feed tray lowering determination control in step S8 of FIG. 12, first, the control unit 5 executes the process of step S11. In this case, the control unit 5 receives the detection signal of the guide width detection sensor 7a. Thereby, the control unit 5 determines whether the width between the current pair of guide members 11a, 11b has changed by a predetermined amount, for example, 10 mm or more, compared to the width of the pair of guide members 11a, 11b previously detected by the guide width detection sensor 7a and stored in the memory M.

[0058] In step S11, it may be determined that the width between the current pair of guide members 11a, 11b has changed by a predetermined amount or more compared to the width between the pair of guide members 11a, 11b previously detected by the guide width detection sensor 7a and stored in the memory M. In this case, the control unit 5 controls the lifting unit 4 to lower the paper feed tray 1 in step S13.

[0059] On the one hand, in step S11, there may be a case where it is determined that the width of the current pair of guide members 11a and 11b has not changed by a predetermined amount or more from the width between the pair of guide members 11a and 11b detected by the guide width detection sensor 7a previously stored in the memory M. In this case, in step S12, the control unit 5 determines whether there is a difference between the current length of the document in the advancing direction of the document and the previous length of the document according to the detection signals of the document length sensors 7b(1) and 7b(2).

[0060] In step S12, if it is determined that there is a difference between the current length of the document and the previous length of the document, in step S13, the control unit 5 drives the lifting motor 42 to lower the paper feed tray 1 of the lifting mechanism 41. On the other hand, in step S12, if it is determined that there is no difference between the current length of the document and the previous length of the document, the control unit 5 repeats the processes of steps S11 and S12.

[0061] In step S14, the control unit 5 determines whether the paper feed tray 1 has been moved to the lower limit position based on whether the paper feed tray lower limit detection sensor 72 is ON. In step S14, if the paper feed tray 1 has not been moved to the lower limit position, the control unit 5 repeats the process of step S14 until the paper feed tray 1 is moved to the lower limit position. In step S14, if the paper feed tray 1 has been moved to the lower limit position, in step S15, the control unit 5 controls the lifting unit 4 to stop the descent of the paper feed tray 1.

[0062] As shown in FIG. 14, in step S16, it is determined whether the paper feed tray 1 has been moved to the upper limit position based on whether the paper feed tray upper limit detection sensor 71 is ON. In step S16, if it is determined that the paper feed tray 1 has been moved to the upper limit position, the control unit 5 executes the process of step S16 again. In step S16, if it is determined that the paper feed tray 1 has not been moved to the upper limit position, the control unit 5 controls the lifting unit 4 to raise the paper feed tray 1 in step S17.

[0063] In step S18, the control unit 5 determines whether or not the paper feed tray 1 has changed to a state where no document is placed thereon based on whether or not the document detection sensor 7b(3) is ON. In step S18, if it is determined that the paper feed tray 1 has changed to a state where no document is placed thereon, the control unit 5 stops the control for raising the paper feed tray 1 by the elevating unit 4 in step S19. Thereafter, the control unit 5 executes the control for lowering the paper feed tray 1 by the elevating unit 4 in step S20. If it is determined in step S18 that the paper feed tray 1 has not changed to a state where no document is placed thereon, the control unit 5 determines whether or not the cover 102 has changed to an open state based on whether or not the cover sensor 73 is ON in step S21.

[0064] In step S21, if it is determined that the cover 102 has changed to an open state, the control unit 5 controls the elevating unit 4 to stop the raising of the paper feed tray 1 in step S24. If it is determined in step S21 that the cover 102 has not changed to an open state, the control unit 5 determines whether or not the paper feed tray 1 has been moved to the upper limit position based on whether or not the paper feed tray upper limit detection sensor 71 is ON in step S22.

[0065] If it is determined in step S22 that the paper feed tray 1 has not been moved to the upper limit position, the control unit 5 repeatedly executes the processes of steps S18 to S22. In step S22, it is possible that it is determined that the paper feed tray 1 has been moved to the upper limit position. In this case, the control unit 5 stores in the memory M the value of the width between the pair of guide members 11a, 11b at present and the size of the document based on the detection by the document length sensors 7b(1), 7b(2) based on the detection signal of the guide width detection sensor 7a in step S23. Thereafter, in step S24, the control unit 5 stops the control for raising the paper feed tray 1 in step S19 and then executes the process of step S1 again.

[0066] FIG. 15 is a flowchart for explaining the processing executed by the control unit 5 of the document transport apparatus 100 of the present embodiment during document transport.

[0067] As shown in FIG. 15, in step S101 (similar to S11 or S12 in FIG. 13), the control unit 5 determines whether the size sensor 7 has detected that the size of the document has been changed. As described above, the size sensor 7 includes a guide width detection sensor 7a, a document length sensor 7b(1), and a document length sensor 7b(2). Therefore, the control unit 5 determines that the size of the document has been changed when any one of the guide width detection sensor 7a, the document length sensor 7b(1), or the document length sensor 7b(2) turns ON or OFF.

[0068] Thereafter, in step S102, when it is determined in step S102 that the size of the document P has been detected as having been changed, the control unit 5 controls the lifting motor 42 of the lifting unit 4 so as to lower the paper feed tray 1 to the lifting unit 4. This is the same as the processing executed by the control unit 5 before document transport, which was described with reference to FIGS. 12 to 14.

[0069] Thereafter, in step S103, after the control unit 5 completes the transport of the document P being transported by the plurality of transport rollers 31, 32, 33, 34, 35, 36, 37, the control unit 5 stops the rotation of the plurality of transport rollers 31, 32, 33, 34, 35, 36, 37. Next, in step S104, the control unit 5 ends the print job that has been executed based on the aforementioned program.

[0070] However, the control unit 5 may lower the paper feed tray 1 after stopping the rotation of the plurality of transport rollers 31, 32, 33, 34, 35, 36, 37 after the document being transported in the transport path 30 has been discharged onto the stacking tray 8. Further, the document transport apparatus 100 may be configured such that the paper feed tray descends after the print job has been stopped. Further, the job is not limited to a print job and may be any type of job.

[0071] (Embodiment 2) The manuscript conveying device 100 according to Embodiment 2 will be described with reference to FIGS. 16 to 24. Note that the description of the points that are the same as those of the manuscript conveying device 100 according to Embodiment 1 will not be repeated below. The manuscript conveying device 100 according to the present embodiment is different from the manuscript conveying device 100 according to Embodiment 1 in the following points.

[0072] FIG. 16 is a perspective view of the manuscript conveying device 100 according to the present embodiment. FIG. 17 is a perspective view showing a state in which the cover 102 of the manuscript conveying device 100 according to the present embodiment is opened.

[0073] As shown in FIGS. 16 and 17, in the present embodiment, it is understood that when the cover 102 is opened from the main body 101, the paper feed roller 21 and the paper feed tray 1 are provided so as to face each other. In the present embodiment, the paper feed roller 21 is configured to be movable up and down, and the position of the paper feed tray 1 is fixed.

[0074] FIG. 18 is a cross-sectional view of the manuscript conveying device 100 according to the present embodiment. FIG. 19 is a functional block diagram showing the overall configuration of the manuscript conveying device 100 according to the present embodiment.

[0075] In the lifting / lowering unit 4 (paper feed motor 22, conveying roller 31, lifting / lowering member 43) of the present embodiment, the paper feed roller 21 is brought into contact with the manuscript P on the paper feed tray 1 by lowering the paper feed roller 21. Also, in the present embodiment, a plurality of conveying rollers 32, 33, 34, 35 are provided instead of the plurality of conveying rollers 32, 33, 34, 35, 36, 37 in Embodiment 1. When the paper feed motor 22 rotates, the conveying roller 31 rotates. At the same time, the lifting / lowering member 43 moves up and down. The rotation of the paper feed motor 22 is transmitted to the paper feed roller 21 via a belt. Therefore, the conveying roller 31 and the paper feed roller 21 rotate in the same direction.

[0076] Note that, similar to the first embodiment, the manuscript conveying device 100 of this embodiment also includes a conveying motor 38 that rotates a plurality of conveying rollers 32, 33, 34, 35 in addition to the paper feeding motor 22. Similar to the first embodiment, when the conveying motor 38 rotates the plurality of conveying rollers 32, the rotation of the plurality of conveying rollers 32 is transmitted by the rotation of the belt, and the plurality of conveying rollers 33, 34, 35 rotate, whereby the manuscript is conveyed in the conveying path 30.

[0077] Specifically, when the paper feeding motor 22 (lifting unit 4) rotates forward (clockwise in FIG. 18), the conveying roller 31 (lifting unit 4) rotates forward. As a result, the lifting member 43 (lifting unit 4) rotates forward about the rotation center axis of the conveying roller 31. At this time, the paper feeding roller 21 attached to the tip of the lifting member 43 rotates forward (descends) about the rotation center axis of the conveying roller 31 in the direction indicated by the arrow in FIG. 18. Therefore, the paper feeding roller 21 approaches the paper feeding tray 1. As a result, the manuscript is sandwiched between the paper feeding tray 1 and the paper feeding roller 21.

[0078] On the other hand, when the paper feeding motor 22 (lifting unit 4) rotates reversely, the conveying roller 31 (lifting unit 4) rotates reversely (counterclockwise in FIG. 18). As a result, the lifting member 43 (lifting unit 4) rotates reversely about the rotation center axis of the conveying roller 31. At this time, the paper feeding roller 21 attached to the tip of the lifting member 43 rotates reversely (ascends) about the rotation center axis of the conveying roller 31 in the direction indicated by the arrow in FIG. 18. Therefore, the paper feeding roller 21 moves away from the paper feeding tray 1. As a result, the paper feeding roller 21 does not contact the manuscript on the paper feeding tray 1.

[0079] Therefore, the conveying roller 31 and the lifting member 43 have the same function as the lifting mechanism 41 of the first embodiment, and the paper feeding motor 22 has the same function as the lifting motor 42 of the first embodiment. However, the paper feeding motor 22 and the conveying roller 31 of this embodiment also have the same function as the paper feeding motor 22 and the conveying roller 31 of the first embodiment. That is, the paper feeding motor 22 and the conveying roller 31 of this embodiment perform the functions of both the paper feeding unit 2 and the lifting unit 4 of the first embodiment.

[0080] The control unit 5 of the document transport device 100 according to the present embodiment executes control to raise and lower the paper feed unit 2 (paper feed roller 21) instead of the paper feed tray 1 by controlling the paper feed motor 22 that rotates a plurality of transport rollers 31. As described above, since the position of the paper feed tray 1 of the present embodiment is fixed, it is not movable.

[0081] FIG. 20 is a schematic cross-sectional view of the document transport device 100 according to the present embodiment, showing a state in which the paper feed roller 21 has been raised and is separated from the document P(1) on the paper feed tray 1.

[0082] As shown in FIG. 20, when the control unit 5 rotates the paper feed motor 22 in the reverse direction, the transport roller 31 is rotated in the reverse direction, whereby the paper feed roller 21 is raised. As a result, as indicated by the arrow in FIG. 20, the paper feed roller 21 rises and moves away from the document P on the paper feed tray 1.

[0083] FIG. 21 is a schematic cross-sectional view of the document transport device 100 according to the present embodiment, showing a state in which the document P(1) on the paper feed tray 1 is being supplied to the transport unit 3 by the paper feed roller 21 because the paper feed roller 21 has been lowered and is in contact with the document P(1).

[0084] As shown in FIG. 21, when the control unit 5 rotates the paper feed motor 22 in the forward direction, the transport roller 31 is rotated in the forward direction, whereby the paper feed roller 21 is lowered. As a result, as indicated by the arrow in FIG. 21, the paper feed roller 21 descends and comes into contact with the document P(1) on the paper feed tray 1.

[0085] FIG. 22 is a schematic cross-sectional view of the document transport device 100 according to the present embodiment, showing a state in which the transport of the document P(1) on the paper feed tray 1 by the transport unit 3 has been completed.

[0086] As shown in FIG. 22, when the size of the document is detected to have changed by the size sensor 7 (guide width detection sensor 7a) during the conveyance of the document P(1), the control unit 5 executes control to reverse-rotate the paper feed motor 22. As a result, the paper feed roller 21 is separated from the paper feed tray 1. As a result, the supply of the document P(2) placed on the paper feed tray 1 to the conveyance path 30 is not performed. Note that when the size of the document is detected to have changed by the size sensor 7 (guide width detection sensor 7a) during the conveyance of the document, the control unit 5 stops the rotation of the paper feed motor 22. However, even when the size of the document is detected to have changed by the size sensor 7 (guide width detection sensor 7a) during the conveyance of the document P(1), the control unit 5 continues the conveyance by the conveyance unit 3 until the conveyance of the document P(1) on the paper feed tray 1 by the conveyance unit 3 is completed.

[0087] As shown in FIGS. 21 and 22, the control unit 5 lowers or raises the paper feed roller 21 instead of the paper feed tray 1 by selecting either forward rotation or reverse rotation of the paper feed motor 22 that also functions as a lifting motor. As a result, the paper feed roller 21 comes into contact with or separates from the document P on the paper feed tray 1.

[0088] FIG. 23 is a flowchart for explaining the processing executed by the control unit 5 of the document conveyance apparatus 100 according to the present embodiment (however, applicable to Embodiment 1) during the conveyance of the document.

[0089] As shown in FIG. 23, in step S50, the control unit 5 supplies the document P to the conveyance path 30 by the paper feed roller 21 by rotating the paper feed motor 22 forward. As a result, the conveyance by the conveyance rollers 31, 32, 33, 34, 35 starts. As a result, the reading of the document by the document reading device starts. In step S51, the control unit 5 determines whether or not a signal instructing to cancel the print job (which may be a job other than the print job) is received from the operation unit 6. If it is determined in step S51 that a signal instructing to cancel the print job is received, the control unit 5 executes the processing of step S56.

[0090] In step S51, it may not be determined that a signal instructing to cancel a print job (which may be a job other than a print job) is received. In this case, in step S52, the control unit 5 receives the detection signal received from the guide width detection sensor 7a. Thereby, the control unit 5 determines whether the width of the current pair of guide members 11a and 11b has changed by a predetermined distance, for example, 10 mm or more, from the width of the pair of guide members 11a and 11b previously detected by the guide width detection sensor 7a and stored in the memory M.

[0091] In step S52, it may be determined that the width of the current pair of guide members 11a and 11b has changed by a predetermined amount or more from the width of the pair of guide members 11a and 11b previously detected by the guide width detection sensor 7a and stored in the memory M. In this case, the process of step S56 is executed.

[0092] In step S52, it may not be determined that the width of the current pair of guide members 11a and 11b has changed by a predetermined amount or more from the width of the pair of guide members 11a and 11b previously detected by the guide width sensor and stored in the memory M. In this case, the control unit 5 executes the process of step S53.

[0093] In step S53, the control unit 5 determines whether the next document is placed on the paper feed tray 1 based on the detection signal of the document detection sensor 7b(3). If it is determined in step S53 that the next document is placed on the paper feed tray 1, then in step S54, the control unit 5 determines whether the next document can be fed.

[0094] If it is determined in step S54 that the next document can be fed, the control unit 5 starts transporting and reading the next document in step S55, and then executes the process of step S51.

[0095] In step S53, there may be a case where it is not determined that the next document is not placed on the paper feed tray 1. In this case, the control unit 5 determines in step S56 whether the conveyance of the document P supplied to the conveyance path 30 by the paper feed roller 21 is completed by the conveyance rollers 31, 32, 33, 34, and 35.

[0096] If it is not determined in step S56 that the conveyance of the document P supplied to the conveyance path 30 by the paper feed roller 21 is completed by the conveyance rollers 31, 32, 33, 34, and 35, the control unit 5 repeats the processes of steps S51 to S56. In step S56, there may be a case where it is determined that the conveyance of the document supplied to the conveyance path 30 by the paper feed roller 21 is completed by the conveyance rollers 31, 32, 33, 34, and 35. In this case, the control unit 5 controls the elevating unit 4 (paper feed motor 22) so as to raise the paper feed roller 21 in step S57. The elevating unit 4 of the present embodiment is composed of a paper feed motor 22, a conveyance roller 31, and an elevating member 43. Therefore, the control unit 5 reversely rotates the conveyance roller 31 by reversely rotating the paper feed motor 22. Thereby, the tip of the elevating member 43 rises, and the paper feed roller 21 provided at the tip of the elevating member 43 rises away from the paper feed tray 1.

[0097] Also by the control of the control unit 5 of the document conveyance device 100 of the present embodiment described above, it is possible to easily and safely stop the conveyance of an incorrect document while preventing paper jams and damage to the paper feed roller 21 in the document conveyance device 100.

[0098] The process executed by the control unit 5 of the document conveyance device 100 of the present embodiment shown in FIG. 23 can also be applied as the process executed by the control unit 5 of the document conveyance device 100 of Embodiment 1. In this case, in step S57, instead of raising the paper feed roller 21, the paper feed tray 1 is lowered. Specifically, in the case of the document conveyance device 100 described in Embodiment 1, in step S57, the control unit 5 controls the elevating unit 4 (elevating motor 42) so as to lower the paper feed tray 1.

[0099] Figure 24 is a flowchart of another example for explaining the processing executed by the control unit 5 of the document transport apparatus 100 according to the present embodiment during document transport. The control unit 5 of the document transport apparatus 100 according to the present embodiment may execute the processing shown in Figure 24 instead of the processing shown in Figure 23.

[0100] As shown in Figure 24, in the processing of another example, in step S201, the control unit 5 determines whether it is detected by the document length sensor 7b(1) or 7b(2) that the length of the document has been changed. In step S202, when it is determined that it is detected that the length of the document has been changed, in step S202, the control unit 5 reversely rotates the paper feed motor 22 (lifting unit 4) so as to raise the paper feed roller 21. However, the control unit 5 continues the conveyance by the conveyance rollers 32, 33, 34, 35 by rotating the conveyance motor 38 until the document is sent out onto the discharge tray 8 from the conveyance path 30.

[0101] Specifically explaining the above control, it is as follows.

[0102] There may be a case where the document length sensor 7b(2) detects that the length of the document P on the paper feed tray 1 has become shorter while the lifting unit 4 (paper feed motor 22, conveyance roller 31, and lifting member 43) keeps the paper feed roller 21 in contact with the document P on the paper feed tray 1. In this case, the control unit 5 controls the lifting unit 4 (conveyance motor 38, conveyance roller 31, and lifting member 43) so as to raise the paper feed roller 21. Also, there may be a case where the document length sensor 7b(1) detects that the length of the document P on the paper feed tray 1 has become longer while the paper feed motor 22 keeps the paper feed roller 21 in contact with the document P on the paper feed tray 1. In this case, the control unit 5 controls the lifting unit 4 (paper feed motor 22, conveyance roller 31, and lifting member 43) so as to raise the paper feed roller 21.

[0103] After that, in step S203, after the control unit 5 completes the conveyance of the document P being conveyed by the plurality of conveyance rollers 31, 32, 33, 34, 35, the control unit 5 stops the rotation of the plurality of conveyance rollers 31, 32, 33, 34, 35. Next, in step S204, the control unit 5 ends the print job (which may be a job other than the print job) that has been executed based on the aforementioned program.

Explanation of Signs

[0104] 1 Paper feed tray 3 Conveyance unit 4 Lifting unit 5 Control unit 6 Operation unit 7 Size sensor 7a Guide width detection sensor 7b, 7b(1), 7b(2) Document length sensor 11a, 11b Guide member 21 Paper feed roller 30 Conveyance path P, P(1), P(2) Document

Claims

1. A paper feed roller for supplying a document to a conveyance path, A paper feed tray on which the document can be placed, A size sensor for detecting the size of the document on the paper feed tray, A lifting / lowering unit that contacts the paper feed roller with the document on the paper feed tray by raising the paper feed tray, A control unit that controls the lifting / lowering unit based on a detection signal from the size sensor, When the size sensor detects that the size of the document is about to be changed while the lifting / lowering unit is in contact with the document on the paper feed tray with the paper feed roller, the control unit controls the lifting / lowering unit to lower the paper feed tray. A document conveyance device.

2. The paper feed tray is configured to guide the document from the paper feed tray to the conveyance path and includes a pair of guide members movable according to the size of the document. The size sensor is a guide width detection sensor that detects that the width between the pair of guide members has changed by a predetermined amount or more. When the guide width detection sensor detects that the width between the pair of guide members has changed by a predetermined amount or more while the lifting / lowering unit is in contact with the document on the paper feed tray with the paper feed roller, the control unit controls the lifting / lowering unit to lower the paper feed tray. The document conveyance device according to Claim 1.

3. The size sensor is a document length sensor that detects the length of the document in the advancing direction of the document on the paper feed tray. When the document length sensor detects that the length of the document on the paper feed tray has become shorter while the lifting / lowering unit is in contact with the document on the paper feed tray with the paper feed roller, the control unit controls the lifting / lowering unit to lower the paper feed tray. The document conveyance device according to Claim 1.

4. The size sensor is a document length sensor that detects the length of the document in the advancing direction of the document on the paper feed tray. When the document length sensor detects that the length of the document on the paper feed tray has become longer while the lifting / lowering unit is in contact with the document on the paper feed tray with the paper feed roller, the control unit controls the lifting / lowering unit to lower the paper feed tray. The document conveyance device according to Claim 1.

5. A paper feed roller for supplying a document to a conveyance path, A paper feed tray on which the document can be placed, A size sensor that detects the size of the document on the paper feed tray, A lifting / lowering unit that contacts the paper feed roller with the document on the paper feed tray by lowering the paper feed roller, A control unit that controls the lifting / lowering unit based on a detection signal from the size sensor, When the size sensor detects that the size of the document is about to be changed while the lifting / lowering unit is in a state where the paper feed roller is in contact with the document on the paper feed tray, the control unit controls the lifting / lowering unit to raise the paper feed roller. A document conveyance device.

6. The paper feed tray is configured to guide the document from the paper feed tray to the conveyance path and includes a pair of guide members movable in accordance with the size of the document. The size sensor is a guide width detection sensor that detects that the width between the pair of guide members has changed by a predetermined amount or more. When the guide width detection sensor detects that the width between the pair of guide members has changed by a predetermined amount or more while the lifting / lowering unit is in a state where the paper feed roller is in contact with the document on the paper feed tray, the control unit controls the lifting / lowering unit to raise the paper feed roller. The document conveyance device according to claim 5.

7. The size sensor is a document length sensor that detects the length of the document in the advancing direction of the document on the paper feed tray. When the document length sensor detects that the length of the document on the paper feed tray has become shorter while the lifting / lowering unit is in a state where the paper feed roller is in contact with the document on the paper feed tray, the control unit controls the lifting / lowering unit to raise the paper feed roller. The document conveyance device according to claim 5.

8. The size sensor is a document length sensor that detects the length of the document in the advancing direction of the document on the paper feed tray. When the document length sensor detects that the length of the document on the paper feed tray has become longer while the lifting / lowering unit is in a state where the paper feed roller is in contact with the document on the paper feed tray, the control unit controls the lifting / lowering unit to raise the paper feed roller. The document conveyance device according to claim 5.

9. The document conveyance device further includes a plurality of conveyance rollers that convey the document along the conveyance path. When the size sensor detects that the size of the original document is about to be changed, the control unit controls the plurality of conveying rollers to complete the conveyance of the original document for which the conveyance by the plurality of conveying rollers has already started. The original document conveying apparatus according to claim 1 or 5.

10. When the size sensor detects that the size of the original document is about to be changed, the control unit controls the paper feed roller to stop further supply of the original document on the paper feed tray to the conveyance path. The original document conveying apparatus according to claim 1 or 5.

11. The apparatus further includes an operation unit that transmits a command signal capable of specifying a job to the control unit based on a user operation. When the size sensor detects that the size of the original document is about to be changed, the control unit stops execution of the job specified by the command signal received from the operation unit. The original document conveying apparatus according to claim 1 or 5.

Images