Medium conveying device, control method and control program

Abstract

To properly detect a bound medium.SOLUTION: A medium conveying device comprises: a pick roller for feeding a medium; a separation roller which is arranged on a downstream side in a medium conveyance direction beyond the pick roller; an arrival detection sensor which is arranged on a downstream side in a medium conveyance direction beyond the separation roller; a floating sensor which detects floating of a medium in between an upstream side of a roller nip of the pick roller and a downstream side of a roller nip of the separation roller; a determination part which determines that a medium is a bound medium in the case that floating of the medium is detected by the floating sensor within a first prescribed period from the detection of a tip of the medium in the conveyance direction according to the arrival detection sensor; and a control part which executes abnormality processing if a medium is determined to be a bound medium according to the determination part.SELECTED DRAWING: Figure 8

Description

Technical Field

[0006] , , , ,

[0007]

[0001] The present invention relates to a medium conveyance device, a control method, and a control program, and more particularly to a medium conveyance device, a control method, and a control program for detecting that a bound medium has been conveyed.

Background Art

[0002] Generally, a medium conveyance device such as a scanner that conveys and images a medium sequentially separates and conveys a plurality of media stacked on a mounting table. However, when a plurality of media are bound with staples or the like, the media may be damaged when separating these media. Therefore, in a medium conveyance device, it is required to appropriately detect such a bound medium and stop the conveyance.

[0003] There is known a medium conveyance device including a contact piece that can be pushed up by the bending of a medium that occurs when trying to separate a bound medium (Patent Document 1). The medium conveyance device of Patent Document 1 determines that a bound medium is being conveyed when the contact piece is pushed up, and stops the conveyance of the medium.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

[0005] In a medium conveyance device, it is required to detect a bound medium with higher accuracy.

[0006] The purpose of the medium conveyance device, the control method, and the control program is to appropriately detect a bound medium.

[0007] The media transport device according to this embodiment is characterized by comprising: a pick roller for feeding media; a separation roller positioned downstream of the pick roller in the media transport direction; an arrival detection sensor positioned downstream of the separation roller in the transport direction for detecting the arrival of the media; a lifting sensor positioned between the upstream side of the roller nip of the pick roller and the downstream side of the roller nip of the separation roller for detecting the lifting of the media; a determination unit that determines the media is a bound medium when the lifting of the media is detected by the lifting sensor within a first predetermined period after the leading edge of the media in the transport direction is detected by the arrival detection sensor; and a control unit that performs abnormal processing when the determination unit determines the media is a bound medium.

[0008] The control method according to the embodiment is a control method for a media transport device having a pick roller for feeding media, a separation roller positioned downstream of the pick roller in the media transport direction, an arrival detection sensor positioned downstream of the separation roller in the transport direction for detecting the arrival of the media, and a lift-up sensor positioned between the upstream side of the roller nip of the pick roller and the downstream side of the roller nip of the separation roller for detecting the lift-up of the media, characterized in that if the lift-up of the media is detected by the lift-up sensor within a first predetermined period after the leading edge of the media in the transport direction is detected by the arrival detection sensor, it is determined that the media is a bound medium, and if it is determined that the media is a bound medium, abnormal processing is performed.

[0009] The control program according to the embodiment is a control program for a media transport device having a pick roller for feeding media, a separation roller positioned downstream of the pick roller in the media transport direction, an arrival detection sensor positioned downstream of the separation roller in the transport direction for detecting the arrival of the media, and a lift-up sensor positioned between the upstream side of the roller nip of the pick roller and the downstream side of the roller nip of the separation roller for detecting the lifting of the media, characterized in that the control program causes the media transport device to determine that the media is a bound medium if the lift-up of the media is detected by the lift-up sensor within a first predetermined period after the leading edge of the media in the transport direction is detected by the arrival detection sensor, and to perform abnormal processing if the media is determined to be a bound medium.

[0010] According to the embodiment, the media transport device, control method, and program enable appropriate detection of the bound media.

[0011] The object and effect of the present invention will be recognized and obtained, in particular, by using the components and combinations indicated in the claims. Both the general description above and the detailed description below are illustrative and descriptive, and do not limit the present invention as described in the claims. [Brief explanation of the drawing]

[0012] [Figure 1] This is a perspective view of the media transport device 100. [Figure 2] This is a schematic diagram illustrating the transport path of the media transport device 100. [Figure 3] This is a perspective view illustrating the configuration of the floating sensor 113. [Figure 4] This is a schematic diagram illustrating the arrangement of the floating sensor 113 and the second medium sensor 116. [Figure 5] This is a block diagram showing an example of the schematic configuration of the media transport device 100. [Figure 6] This is a block diagram showing an example of the schematic configuration of the storage device 140 and the processing circuit 150. [Figure 7] This is a flowchart illustrating an example of the media reading process. [Figure 8] This is a flowchart illustrating an example of the decision-making process. [Figure 9] This is a diagram illustrating the lifting of bound materials. [Figure 10] This is a diagram illustrating the detection of bound media. [Figure 11] This is a diagram illustrating the detection of the rear-end curling medium. [Figure 12] This is a diagram illustrating the detection of tip curl media. [Figure 13] This is a diagram illustrating the detection of tip curl media. [Figure 14] This is a diagram illustrating the detection of wrinkle media. [Figure 15] This is a schematic diagram illustrating the transport path of the media transport device 200. [Figure 16] This is a block diagram showing an example of the schematic configuration of the processing circuit 350. [Modes for carrying out the invention]

[0013] The following describes a media transport device, control method, and program representing one aspect of the present invention, with reference to the drawings. It should be noted that the technical scope of the present invention is not limited to these embodiments, but extends to the invention described in the claims and its equivalents.

[0014] FIG. 1 is a perspective view showing a media conveyance device 100 configured as an image scanner. The media conveyance device 100 conveys and images a medium which is a document. The medium is paper, cardboard, or the like. Further, the medium includes a bound medium in which a plurality of media are bound by a binding tool such as a staple, a string, or a clip, and a card medium that is smaller and thicker than paper, such as a driver's license or an IC card. The media conveyance device 100 may be a facsimile machine, a copying machine, a printer multifunction peripheral (MFP), or the like. Note that the media conveyance device 100 may be a printer or the like. In this case, the medium to be conveyed is a printing object or the like.

[0015] The media conveyance device 100 includes a first housing 101, a second housing 102, a placement table 103, a discharge table 104, an operation device 105, a display device 106, and the like.

[0016] The first housing 101 is disposed above the media conveyance device 100 and is engaged with the second housing 102 by a hinge so as to be openable and closable when cleaning the inside of the media conveyance device 100 or when loading a medium.

[0017] The placement table 103 is engaged with the second housing 102 so as to be able to place the conveyed medium. The placement table 103 is provided on the side surface of the second housing 102 on the media supply side so as to be movable in a substantially vertical direction (height direction) A1 by a motor (not shown). The placement table 103 is disposed at the lower end position so that the medium can be easily placed when the medium is not being conveyed, and rises to a position where the uppermost placed medium contacts a pick roller described later when the medium is being conveyed. The discharge table 104 is formed on the first housing 101 so as to be able to hold the discharged medium, and stacks the discharged medium.

[0018] The operation device 105 has an input device such as a button and an interface circuit that acquires a signal from the input device, receives an input operation by a user, and outputs an operation signal corresponding to the input operation of the user. The display device 106 has a display including a liquid crystal, an organic EL (Electro-Luminescence), or the like, and an interface circuit that outputs image data to the display, and displays the image data on the display.

[0019] In Figure 1, arrow A2 indicates the media transport direction, arrow A3 indicates the media discharge direction, and arrow A4 indicates the width direction perpendicular to the media transport direction. Hereafter, "upstream" refers to the upstream direction of media transport direction A2 or media discharge direction A3, and "downstream" refers to the downstream direction of media transport direction A2 or media discharge direction A3.

[0020] Figure 2 is a diagram illustrating the transport path inside the media transport device 100. The transport path inside the media transport device 100 includes a first media sensor 111, a pick roller 112, a lift sensor 113, a feed roller 114, a brake roller 115, a second media sensor 116, first to eighth transport rollers 117a to h, first to eighth driven rollers 118a to h, a first imaging device 119a, and a second imaging device 119b, etc. Hereafter, the first imaging device 119a and the second imaging device 119b may be collectively referred to as imaging device 119.

[0021] The number of each of the pick roller 112, feed roller 114, brake roller 115, first to eighth conveying rollers 117a to h and / or first to eighth driven rollers 118a to h is not limited to one, but may be multiple. In that case, the multiple pick rollers 112, feed roller 114, brake roller 115, first to eighth conveying rollers 117a to h and / or first to eighth driven rollers 118a to h are arranged side by side with a spacing of A4 in the width direction.

[0022] The surface of the first housing 101 facing the second housing 102 forms the first guide 101a of the medium transport path, and the surface of the second housing 102 facing the first housing 101 forms the second guide 102a of the medium transport path.

[0023] The first medium sensor 111 is positioned on the mounting table 103, that is, upstream of the feed roller 114 and the brake roller 115, and detects the state of the medium being placed on the mounting table 103. The first medium sensor 111 is a contact detection sensor that sends a predetermined current when the medium is in contact or when the medium is not in contact, and determines whether or not the medium is placed on the mounting table 103. The first medium sensor 111 generates and outputs a first medium signal whose signal value changes depending on whether or not the medium is placed on the mounting table 103. Note that the first medium sensor 111 is not limited to a contact detection sensor, and any other sensor capable of detecting the presence or absence of medium, such as a light detection sensor, may be used as the first medium sensor 111.

[0024] The pick roller 112 is provided on the first housing 101 and comes into contact with the medium placed on the mounting platform 103, which is raised to approximately the same height as the medium transport path, and feeds the medium downstream.

[0025] The lift sensor 113 is installed inside the first housing 101, downstream of the pick roller 112. The lift sensor 113 detects the lifting of the medium fed by the pick roller 112. Lifting of the medium refers to the curve of the fed medium toward the first housing 101 relative to the transport path. The configuration of the lift sensor 113 will be described later with reference to Figure 3.

[0026] The feed roller 114 is located inside the first housing 101, downstream of the lift sensor 113, and feeds the medium fed by the pick roller 112 further downstream. The brake roller 115 is located inside the second housing 102, opposite the feed roller 114. The feed roller 114 and the brake roller 115 are examples of separation rollers, which perform a medium separation operation and feed the medium one sheet at a time. The feed roller 114 is located above the brake roller 115, and the medium transport device 100 feeds the medium using a so-called top-feed method.

[0027] The second medium sensor 116 is an example of an arrival detection sensor and is positioned downstream of the feed roller 114 and the brake roller 115. The second medium sensor 116 detects whether or not a medium is present at its location. The second medium sensor 116 is a recurrent prism sensor and includes a light-emitting element, a light-receiving element, and a light-guiding member.

[0028] The light-emitting element and the light-receiving element are positioned outside the medium transport path, with the second guide 102a in between. The light guide member is a light guide tube such as a U-shaped prism, and is positioned outside the medium transport path, with the first guide 101a in between, so that both ends face the light-emitting element and the light-receiving element, respectively. The light-emitting element is an LED (Light Emitting Diode) or the like, and emits light toward the light guide member across the medium transport path. The light-receiving element receives light emitted from the light-emitting element and guided by the light guide member. The light-receiving element generates and outputs a second medium signal, which is an electrical signal corresponding to the intensity of the received light. When a medium is present at the position of the second medium sensor 116, the light emitted from the light-emitting element is blocked by the medium, so the signal value of the second medium signal changes depending on whether a medium is present or not at the position of the second medium sensor 116. As a result, the second medium sensor 116 detects the arrival of the medium.

[0029] The configuration of the second medium sensor 116 is not limited to the example described above. For example, a reflective member such as a mirror may be used instead of the light guide member. Also, the second medium sensor 116 may consist only of a light-emitting element and a light-receiving element. In this case, the light-emitting element and the light-receiving element are arranged in the first housing 101 and the second housing 102, respectively, so as to face each other across the medium transport path. Furthermore, the second medium sensor 116 may be a contact detection sensor similar to the first medium sensor 111.

[0030] The first to eighth conveyor rollers 117a to h and the first to eighth driven rollers 118a to h are located downstream of the feed roller 114 and the brake roller 115, and convey the medium supplied by the feed roller 114 and the brake roller 115 toward the downstream side. The first to eighth conveyor rollers 117a to h and the first to eighth driven rollers 118a to h are each arranged facing each other across the medium conveying path.

[0031] The first imaging device 119a is located downstream of the first and second transport rollers 117a and 117b and the first and second driven rollers 118a and 118b in the medium transport direction A2. The first imaging device 119a has a line sensor using a 1:1 optical system type CIS (Contact Image Sensor) with image sensors made of CMOS (Complementary Metal Oxide Semiconductor) arranged linearly in the main scanning direction. The first imaging device 119a has a lens that forms an image on the image sensor and an A / D converter that amplifies the electrical signal output from the image sensor and performs analog / digital (A / D) conversion. The first imaging device 119a captures the surface of the transported medium to generate an input image and outputs it.

[0032] The second imaging device 119b is located downstream of the first and second transport rollers 117a and 117b and the first and second driven rollers 118a and 118b in the media transport direction A2. The second imaging device 119b has a line sensor using a 1:1 optical system type CIS (Contact Image Sensor) with CMOS (Complementary Metal Oxide Semiconductor) image sensors arranged linearly in the main scanning direction. The second imaging device 119b has a lens that forms an image on the image sensor and an A / D converter that amplifies the electrical signal output from the image sensor and performs analog-to-digital (A / D) conversion. The second imaging device 119b captures the back surface of the transported medium to generate and output an input image.

[0033] The media transport device 100 may have only one of the first imaging device 119a and the second imaging device 119b, and may read only one side of the media. Furthermore, instead of a CIS line sensor of the 1:1 optical system type equipped with a CMOS image sensor, a CIS line sensor of the 1:1 optical system type equipped with a CCD (Charge Coupled Device) image sensor may be used. Alternatively, a reduction optical system type line sensor equipped with a CMOS or CCD image sensor may be used.

[0034] The media placed on the mounting table 103 is transported between the first guide 101a and the second guide 102a in the media transport direction A2 by the rotation of the pick roller 112 and the feed roller 114 in the media transport directions A5 and A6, respectively. On the other hand, when multiple media are placed on the mounting table 103, the brake roller 115 rotates in the opposite direction A7 to the media transport direction, so that only the media in contact with the feed roller 114 are separated from the media placed on the mounting table 103.

[0035] The medium is guided by the first guide 101a and the second guide 102a, and is fed to the imaging position of the imaging device 119 as the first and second transport rollers 117a and 117b rotate in the directions of arrows A8 and A9, and is imaged by the imaging device 119. Furthermore, the medium is discharged onto the discharge platform 104 as the third to eighth transport rollers 117c and 117h rotate in the directions of arrows A10 and A15, respectively. The discharge platform 104 loads the medium discharged by the eighth transport roller 117h.

[0036] Figure 3 is a perspective view illustrating the configuration of the floating sensor 113.

[0037] The floating sensor 113 has an arm 113a and a horseshoe-shaped sensor 113b.

[0038] Arm 113a is provided above the medium transport path, extending in the medium transport direction A2, and positioned so that its lower surface faces the second guide 102a at a predetermined distance. When multiple lift sensors 113 are provided, each arm 113a is positioned at the same height in the height direction A1. The downstream end 113c of arm 113a is rotatably attached to the first housing 101 so that the upstream end 113d swings. The predetermined distance is set to the maximum height to which the medium can bend during medium feeding, plus a margin. As a result, if the medium being fed is not floating, the medium is transported without contacting arm 113a. If the medium being fed floats, the medium contacts arm 113a, causing arm 113a to rotate and rise. That is, arm 113a is positioned to rise in response to the floating of the medium.

[0039] The horseshoe-shaped sensor 113b has a light-emitting element 113e, a light-receiving element 113f, and a connection part 113g that connects the light-emitting element 113e and the light-receiving element 113f. The light-emitting element 113e and the light-receiving element 113f are arranged to face each other. The light-emitting element 113e is an LED or the like, and emits light toward the light-receiving element 113f. The light-receiving element 113f is a photodiode or the like. The light-emitting element 113e and the light-receiving element 113f are examples of a light-emitting part and a light-receiving part, respectively. The light-receiving element 113f is provided facing the light-emitting element 113e with the arm 113a in between, and detects light from the light-emitting element 113e. The light-receiving element 113f generates and outputs a floating detection signal, which is an electrical signal corresponding to the intensity of the detected light.

[0040] The arm 113a is positioned between the light-emitting element 113e and the light-receiving element 113f in its initial state, and is positioned so as not to face the light-emitting element 113e and the light-receiving element 113f when it is raised. In other words, the arm 113a is formed to block light from the light-emitting element 113e to the light-receiving element 113f when it is not raised, and to allow light from the light-emitting element 113e to pass to the light-receiving element 113f when it is raised. As a result, the lift detection signal has a different signal value depending on whether the supplied medium is lifted or not. That is, the lift sensor 113 detects the lifting of the medium by detecting the rise of the arm 113a when the light-receiving element 113f detects light from the light-emitting element 113e.

[0041] Figure 4 is a diagram illustrating the arrangement of the buoyancy sensor 113 and the second medium sensor 116. Figure 4 is a schematic diagram showing the positional relationship between the buoyancy sensor 113 and the second medium sensor 116 when viewed from above along the transport path.

[0042] In the example shown in Figure 4, two lift sensors 113 are positioned on the outside in the width direction A4 relative to the pick roller 112 and the feed roller 114, respectively. The configurations of the two lift sensors 113 are the same except that they are symmetrical with respect to the width direction A4. The number of lift sensors 113 is not limited to two; there may be one or three or more.

[0043] The lifting sensor 113 is positioned at a predetermined distance from the pick roller 112 and the feed roller 114 in the width direction A4. The predetermined distance is set so that when a medium with the smallest width direction A4 length (e.g., A5 size) among the media that are most likely to be bound with staples or clips is transported, the end of that medium in the width direction A4 passes under the arm 113a. As a result, the lifting sensor 113 can detect the lifting of any medium that can be transported by the media transport device 100.

[0044] The upstream end 113d of the arm 113a of the lift sensor 113 is located upstream of the upstream end of the roller nip 112a of the pick roller 112. Also, the downstream end 113c of the arm 113a of the lift sensor 113 is located downstream of the downstream ends of the roller nip 114a of the feed roller 114 and the brake roller 115. As a result, the lift sensor 113 detects the lift of the medium that occurs between the upstream side of the roller nip 112a of the pick roller 112 and the downstream side of the roller nip 114a of the feed roller 114 and the brake roller 115.

[0045] The second medium sensor 116 is positioned downstream of the brake roller 115. The second medium sensor 116 is positioned between the two brake rollers 115, particularly approximately in the center in the width direction A4. In the example shown in Figure 4, only one second medium sensor 116 is positioned, but multiple second medium sensors 116 may be arranged side by side with spacing along the width direction A4.

[0046] Figure 5 is a block diagram showing an example of the schematic configuration of the media transport device 100. In addition to the configuration described above, the media transport device 100 further includes a motor 131, an interface device 132, a storage device 140, and a processing circuit 150, etc.

[0047] The motor 131 includes one or more motors and, by control signals from the processing circuit 150, rotates the pick roller 112, the feed roller 114, the brake roller 115, and the first to eighth transport rollers 117a to h to feed and transport the medium. Note that the first to eighth driven rollers 118a to h may be configured to rotate by the driving force from the motor, rather than rotating in accordance with the rotation of each transport roller.

[0048] The interface device 132 has an interface circuit similar to a serial bus such as USB, and electrically connects to an information processing device (not shown) (e.g., a personal computer, a portable information terminal, etc.) to transmit and receive read images and various types of information. Alternatively, instead of the interface device 132, a communication unit may be used that has an antenna for transmitting and receiving wireless signals and a wireless communication interface circuit for transmitting and receiving signals via a wireless communication line according to a predetermined communication protocol. The predetermined communication protocol is, for example, a wireless LAN (Local Area Network).

[0049] The storage device 140 includes memory devices such as RAM (Random Access Memory) and ROM (Read Only Memory), fixed disk devices such as hard disks, or portable storage devices such as flexible disks and optical disks. The storage device 140 also stores computer programs, databases, tables, etc., used for various processes of the media transport device 100. The computer programs may be installed into the storage device 140 from a computer-readable, non-temporary portable recording medium using a known setup program. Examples of portable recording media include CD-ROMs (Compact Disc Read Only Memory) and DVD-ROMs (Digital Versatile Disc Read Only Memory).

[0050] The processing circuit 150 is a circuit that operates based on a program pre-stored in the memory device 140. The processing circuit 150 is, for example, a CPU (Central Processing Unit). A DSP (Digital Signal Processor), LSI (Large Scale Integration), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array), etc. may be used as the processing circuit 150.

[0051] The processing circuit 150 is connected to the operating device 105, display device 106, first medium sensor 111, lift sensor 113, second medium sensor 116, imaging device 119, motor 131, interface device 132, and storage device 140, and controls each of these parts. The processing circuit 150 controls the motor 131 to transport the medium, controls the imaging device 119 to acquire an input image, and transmits the acquired input image to the information processing device via the interface device 132. The processing circuit 150 also determines whether the transported medium is a bound medium based on the lift detection signal received from the lift sensor 113 and the second medium signal received from the second medium sensor 116.

[0052] Figure 6 shows a schematic configuration of the storage device 140 and the processing circuit 150.

[0053] The memory device 140 stores various programs, such as the control program 141 and the determination program 142. Each of these programs is a functional module implemented by software running on the processor. The processing circuit 150 reads each program stored in the memory device 140 and functions as the control unit 151 and determination unit 152 by operating according to each program it has read.

[0054] Figure 7 is a flowchart illustrating an example of the operation of the media reading process performed by the media transport device 100. The media reading process is realized by the processing circuit 150 cooperating with each element of the media transport device 100 based on a program stored in the storage device 140.

[0055] First, the control unit 151 waits until it receives an operation signal instructing the reading of the medium (S101). The operation signal is supplied from the operating device 105 to the control unit 151 in response to the user inputting a medium reading instruction to the operating device 105. Alternatively, the operation signal may be supplied from the information processing device via the interface device 132 in response to the user inputting a reading instruction to the information processing device.

[0056] Next, the control unit 151 determines whether or not a medium is placed on the mounting table 103 based on the first medium signal output from the first medium sensor 111 (S102). If no medium is placed (S102-No), the control unit 151 terminates the medium reading process.

[0057] If a medium is placed on the platform (S102-Yes), the control unit 151 drives the motor to move the platform 103 and raises the platform 103 to a position where the medium can be fed. The control unit 151 drives the motor 131 to rotate the pick roller 112, the feed roller 114, the brake roller 115 and the first to eighth transport rollers 117a to h, and feeds and transports the medium placed on the platform 103 (S103).

[0058] Next, the determination unit 152 performs a determination process (S104). In the determination process, the determination unit 152 determines whether the transported medium is a bound medium or not. Details of the determination process will be described later.

[0059] Next, the control unit 151 determines in the determination process whether or not the transported medium is determined to be a bound medium (S105). If the transported medium is determined to be a bound medium (S105-Yes), the control unit 151 outputs a notification that it is a bound medium (S106). The control unit 151 outputs the notification that it is a bound medium by displaying it on the display device 106, thereby notifying the user. The control unit 151 may also output a notification signal indicating that it is a bound medium by transmitting it to the information processing device via the interface device 132, thereby notifying the user. Next, the control unit 151 stops the transport of the medium by stopping the motor 131 (S110), and terminates the medium reading process. Note that outputting a notification that it is a bound medium and stopping the transport of the medium are examples of error handling.

[0060] The control unit 151 can prevent media jams and damage by stopping the transport of the media when a stapled medium is transported. Furthermore, the control unit 151 can prevent staples or clips used to bind the media from entering the transport path and scratching the glass surface of the imaging device 119. As a result, users no longer need to check whether the transported media is stapled before transport, improving user convenience and reducing the processing time for media reading.

[0061] If it is determined that the transported medium is not a bound medium (S105-No), the control unit 151 determines whether the rear end of the medium has passed the imaging position of the imaging device 119 (S107). The control unit 151 periodically acquires a second medium signal from the second medium sensor 116, and determines that the rear end of the medium has passed the position of the second medium sensor 116 when the signal value of the second medium signal changes from a value indicating the presence of medium to a value indicating the absence of medium. The control unit 151 determines that the rear end of the medium has passed the imaging position when a predetermined time has elapsed since the rear end of the medium passed the position of the second medium sensor 116. The predetermined time is set to the time obtained by adding a margin to the time it takes for the medium to be transported from the second medium sensor 116 to the imaging position. If the rear end of the medium has not yet passed the imaging position (S107-No), the control unit 151 returns to processing S104 and repeats processing S104 to S107.

[0062] When the trailing end of the medium passes the imaging position (S107-Yes), the control unit 151 acquires the input image from the imaging device 119. The control unit 151 transmits the acquired input image to the information processing device via the interface device 132 (S108).

[0063] Next, the control unit 151 determines whether or not a medium is placed on the mounting table 103 based on the first medium signal output from the first medium sensor 111 (S109). If a medium is placed (S109-Yes), the control unit 151 returns to processing S104 and repeats processing S104 to S109. If no medium is placed (S109-No), the control unit 151 stops the motor 131 (S110) and terminates the medium reading process.

[0064] Figure 8 is a flowchart illustrating an example of the operation of the determination process. The determination process is executed in S104 of the media reading process.

[0065] First, the determination unit 152 determines whether or not the state of the medium to be supplied has been identified (S201). If the state of the medium has been identified, the determination unit 152 terminates the determination process.

[0066] If the state of the medium has not yet been determined, the determination unit 152 determines the current detection period (S202). The determination unit 152 determines that the current detection period is the curl detection period if the first time has not elapsed since the start of medium feeding, i.e., since the start of rotation of the pick roller 112. The first time is set to the time required for the leading edge of the medium to move from the downstream end of the mounting table 103 to the upstream end of the roller nip 114a of the feeding roller 114, or a shorter time. The determination unit 152 may calculate the elapsed time based on the amount of drive by the control unit 151 driving the motor 131. The leading edge of the medium refers to the downstream end of the medium. That is, the curl detection period is set to the time from the start of rotation of the pick roller 112 until the point in time when the leading edge of the medium fed by the pick roller 112 reaches the upstream end of the roller nip 114a of the feeding roller 114, or when it reaches that point. The curl detection period is an example of a second predetermined period from the start of rotation of the pick roller 112 until the arrival of the medium is detected by the second medium sensor 116.

[0067] The determination unit 152 may also detect the timing of the start of rotation of the pick roller 112 using a roller encoder (not shown). The roller encoder has a disc that rotates in conjunction with the rotation of the pick roller 112 and has a plurality of slits along its outer circumference, and a light emitter and a light receiver provided opposite each other on either side of the disc. The light emitter is an LED or the like, and emits light toward the disc and the light receiver. The light receiver is a photodiode or the like, and detects the light emitted by the light emitter and outputs a current corresponding to its intensity. When the pick roller 112 and the disc are rotating, the state in which the light from the light emitter is blocked by the disc switches between a state in which the light from the light emitter passes through the slits in the disc and is detected by the light receiver, so the current value output by the light receiver changes. Therefore, the determination unit 152 can detect the rotation of the pick roller 112 based on the change in the current value output by the light receiver of the roller encoder.

[0068] On the other hand, if the curl detection period has elapsed and the leading edge of the medium has not been detected by the second medium sensor 116, the determination unit 152 determines that the current detection period is the wrinkle detection period. The determination unit 152 determines whether or not the leading edge of the medium in the transport direction A2 has been detected by the second medium sensor 116. The determination unit 152 periodically acquires a second medium signal from the second medium sensor 116, and determines that the leading edge of the medium has been detected by the second medium sensor 116 when the signal value of each second medium signal changes from a value indicating that no medium exists to a value indicating that medium exists. That is, the wrinkle detection period is set to the time before the leading edge of the medium fed by the pick roller 112 passes the upstream end of the roller nip 114a of the feed roller 114, or the period from the time it passes until it reaches the position of the second medium sensor 116. The wrinkle detection period is the period after the curl detection period has elapsed and before the binding medium detection period described later.

[0069] On the other hand, the determination unit 152 determines that the current detection period is the bound media detection period if the second time has not elapsed since the wrinkle detection period. The second time is set to the maximum time required from when the leading edge of a medium with a bound end passes the position of the second medium sensor 116 until the medium starts to lift up, for example, when a medium with a bound leading edge is fed. The second time is set appropriately based on the size of the medium that the medium transport device 100 can transport in the medium transport direction A2, and the length of the arm 113a in the medium transport direction A2, for example, to the time it takes for the medium to travel any distance between 30 mm and 100 mm. That is, the bound media detection period is set to a predetermined period from when the leading edge of the medium fed by the pick roller 112 passes the position of the second medium sensor 116. The bound media detection period is an example of a first predetermined period from when the leading edge of the medium in the transport direction A2 is detected by the second medium sensor 116.

[0070] If the current detection period is the curl detection period, the determination unit 152 determines whether or not the media has been detected to have lifted by any of the lift sensors 113 (S203). The determination unit 152 acquires lift signals from each lift sensor 113, and determines that the lift sensor 113 has detected the media to have lifted if the signal value of any of the lift signals is equal to or greater than the lift threshold. The lift threshold is set to a value between the signal value of the lift signal output from the light-receiving element 113f when the arm 113a of the lift sensor 113 is blocking the light from the light-emitting element 113e, and the signal value of the lift signal output from the light-receiving element 113f when the light from the light-emitting element 113e is directly received by the light-receiving element 113f.

[0071] If lifting is detected within the curl detection period (S203-Yes), the determination unit 152 determines that the medium is a tip-curled medium and not a bound medium (S204), and terminates the determination process. A bound medium is a medium in which multiple mediums are bound together at their leading ends with fasteners such as staples, string, or clips, while a tip-curled medium is a medium in which the leading end (an area spanning one end or the entire width in the A4 width direction) is curved or bent upward. In other words, if lifting of the medium is detected within the curl detection period, the determination unit 152 determines that the medium is not a bound medium, regardless of whether lifting of the medium is detected within the bound medium detection period. On the other hand, if lifting is not detected (S203-No), the determination unit 152 terminates the determination process without yet determining the state of the medium.

[0072] If the current detection period is the wrinkle detection period, the determination unit 152 determines whether or not the media has been detected to lift a predetermined number of times or more by any of the lift sensors 113 within the wrinkle detection period (S205). The determination unit 152 determines that the media has been detected to lift a predetermined number of times or more if, within the wrinkle detection period, the signal value of the lift signal output from any of the lift sensors 113 changes from a value below the lift threshold to a value above the lift threshold a predetermined number of times or more. The predetermined number of times is any number of two or more, for example, three times.

[0073] If the media is detected to lift up a predetermined number of times or more within the wrinkle detection period (S205-Yes), the determination unit 152 determines that the media is a wrinkled media and not a bound media (S206), and terminates the determination process. A wrinkled media is a media in which multiple parts other than the leading edge are bent upward. On the other hand, if the media has not yet been detected to lift up a predetermined number of times or more (S205-No), the determination unit 152 terminates the determination process without yet determining the state of the media.

[0074] If the current detection period is the binding media detection period, the determination unit 152 determines whether or not the media has been detected to be lifted (S207).

[0075] If lifting of the media is detected within the binding media detection period (S207-Yes), the determination unit 152 determines that the media is a binding medium (S208) and terminates the determination process. If lifting of the media is not detected within the binding media detection period (S207-No), the determination unit 152 terminates the determination process without yet determining the state of the media.

[0076] If the current detection period is after the binding media detection period has elapsed, the determination unit 152 determines that the media is a normal media without determining whether or not it is a binding media (S209), and terminates the determination process. A normal media is a media that is neither a binding media, a wrinkled media, nor a media with a curled tip.

[0077] Figure 9 illustrates the lifting that occurs when the binding medium is fed by the feed roller 114. Figure 9 is a view from above of the state in which the leading edge of the binding medium has passed through the separation section (feed roller 114 and brake roller 115) and reached the position of the second medium sensor 116, causing the binding medium to lift.

[0078] When the leading edge of the binding medium passes through the separation section, the medium M1 that is bound on the upper side and in contact with the feed roller 114 is subjected to a force that pushes it downstream at the contact point C with the feed roller 114. On the other hand, the medium M2 that is not in contact with the feed roller 114 is subjected to a force that pushes it upstream by the brake roller 115, and therefore is subjected to a force that pushes it upstream at the binding position S. As a result, as shown in Figure 9, a lift-up D occurs in the region between the contact point C with the feed roller 114 of the medium M1 and the binding position S.

[0079] The lift-up D generally occurs at a position outside the feed roller 114 in the width direction A4. Therefore, the lift-up D is detected by the lift-up sensor 113, which is located outside the feed roller 114 in the width direction A4.

[0080] Figure 10 is a schematic diagram illustrating the detection of the binding medium. Figure 10(A) is a side view of the state before the binding medium reaches the position of the feed roller 114. As shown in Figure 10(A), no lifting occurs in the binding medium before it reaches the position of the feed roller 114.

[0081] Figure 10(B) shows the state after some time has passed since the state shown in Figure 10(A), where the leading edge of the binding medium has passed through the separation section and been detected by the second medium sensor 116. As explained using Figure 9, when the leading edge of the binding medium passes through the separation section, a lift occurs in the width direction A4 at a position outside the feed roller 114. As a result, the arm 113a of the lift sensor 113 is pushed upward, and the light-receiving element 113f of the horseshoe-shaped sensor 113b receives light from the light-emitting element 113e, thus detecting the lift of the medium.

[0082] In other words, when a binding medium is fed, no lifting is detected before the leading edge of the medium reaches the position of the second medium sensor 116 located downstream of the separation unit, and lifting is detected after the leading edge of the medium reaches the position of the second medium sensor 116. Therefore, in the determination process S208, it is determined that it is a binding medium.

[0083] Figure 11 is a schematic diagram illustrating the detection of a rear-end curled medium. A rear-end curled medium is a medium in which the rear end (one end or the entire width in the width direction A4) opposite the leading end of the medium is curved or bent upward. Figure 11 shows the state after some time has passed since the leading end of the rear-end curled medium was detected by the second medium sensor 116.

[0084] As shown in Figure 11, when the leading edge of the rear-end curled medium passes the position of the second medium sensor 116 and is further transported, the rear end of the medium lifts up and comes into contact with the lower part of the arm 113a of the sensor 113. As a result, the arm 113a is pushed up by the rear end of the medium, and the light-receiving element 113f in the horseshoe-shaped sensor 113b receives light from the light-emitting element 113e, thus detecting the lifting of the medium.

[0085] In this way, when a rear-end curled medium is fed, the lift is detected after the leading edge of the medium reaches the position of the second medium sensor 116 and the rear end of the medium reaches below the arm 113a. Therefore, by setting the binding medium detection period to after the leading edge of the medium reaches the position of the second medium sensor 116 and before the rear end of the medium reaches below the arm 113a, the determination process S209 does not determine whether or not the rear-end curled medium is a binding medium. Thus, the medium transport device 100 can prevent itself from mistakenly determining the rear-end curled medium as a binding medium.

[0086] Figure 12 is a schematic diagram illustrating the detection of tip-curling media. Figure 12(A) is a side view of the state before the tip of the tip-curling media reaches the position of the feed roller 114. As shown in Figure 12(A), before the tip-curling media reaches the position of the feed roller 114, the arm 113a of the lift sensor 113 is pushed upward by the tip of the media, and the lift of the media is detected.

[0087] Figure 12(B) shows the state after some time has passed since the state shown in Figure 12(A), where the tip of the tip-curled medium has passed through the separation section and been detected by the second medium sensor 116. Only the tip of the tip-curled medium is curved or bent upward, and as the tip of the tip-curled medium passes through the separation section, it is pressed down by the separation section. Therefore, after reaching the position of the second medium sensor 116, no lifting of the medium is detected.

[0088] Figure 13 shows a state in which multiple tip-curled media are fed overlapping, and the tip of the media in contact with the feed roller 114 has passed through the separation section. In this case, the media that has passed through the separation section is pushed up by the media that are not in contact with the feed roller 114, and it is possible that the media may still be detected floating up even after its tip has passed through the separation section and reached the position of the second media sensor 116.

[0089] When a tip-curled medium is fed, lifting is detected before the tip of the medium reaches the position of the second medium sensor 116. Therefore, the tip-curled medium is detected in the determination process S204. Also, when a tip-curled medium is fed, there are cases where lifting is detected after the tip of the medium reaches the position of the second medium sensor 116, and cases where lifting is not detected. If the determination unit 152 detects lifting of the medium during the curl detection period, it determines that the medium is not a bound medium, regardless of whether lifting was detected during the bound medium detection period, thereby preventing the system from mistakenly identifying a tip-curled medium as a bound medium. As a result, the medium transport device 100 can prevent itself from mistakenly stopping the feeding of the medium when a tip-curled medium is fed, and can suppress an increase in the time required for the medium reading process.

[0090] Figure 14 is a schematic diagram illustrating the detection of wrinkled media. Figure 14(A) is a side view of the state before the leading edge of the wrinkled media reaches the position of the feed roller 114. As shown in Figure 14(A), before the wrinkled media reaches the position of the feed roller 114, the arm 113a of the lift sensor 113 is pushed upward by the portion that bends above the media, and the light-receiving element 113f in the horseshoe-shaped sensor 113b receives light from the light-emitting element 113e, thus detecting the lifting of the media.

[0091] Figure 14(B) shows the state after some time has passed since the state shown in Figure 14(A). Because multiple parts of the wrinkled medium are bent upward, the lifting of the medium is detected multiple times before the leading edge of the wrinkled medium reaches the position of the second medium sensor 116.

[0092] Thus, when a wrinkled medium is fed, lifting is detected multiple times before the leading edge of the medium reaches the feeding roller. Furthermore, because the portion of the wrinkled medium other than the leading edge is bent upward, the lifting of the wrinkled medium is detected later than the lifting of the medium with a curled tip. Therefore, the wrinkled medium is detected in the determination process S206. If the determination unit 152 detects lifting of the medium multiple times during the wrinkle detection period, it determines that the medium is not a bound medium, thereby preventing it from mistakenly identifying the wrinkled medium as a bound medium. As a result, the medium transport device 100 can prevent it from mistakenly stopping the feeding of the medium when a wrinkled medium is fed, and can suppress an increase in the time required for the medium reading process.

[0093] Furthermore, the determination unit 152 can suppress the erroneous determination that a binding medium has been fed when a leading-end curl medium, wrinkle medium, or trailing-end curl medium has been fed, thereby improving the detection accuracy of the binding medium. As a result, if the media transport device 100 is equipped with a switchable ON / OFF function for detecting the binding medium, the default setting can be set to ON, thereby improving user convenience.

[0094] As described above, the media transport device 100 according to this embodiment determines that a medium is a bound medium when the lifting of the medium is detected by the lifting sensor 113 within the bound medium detection period. This enables the media transport device 100 to appropriately detect bound mediums.

[0095] Furthermore, by detecting the lifting of the leading edge of the medium, the medium transport device 100 can detect earlier that the medium is a bound medium than by detecting when the trailing edge of the medium rides onto the side guides provided on the mounting table 103. Therefore, when a bound medium is fed, the medium transport device 100 can stop feeding the medium early, thereby suppressing damage to the medium.

[0096] Furthermore, the media transport device 100 determines that a medium is a tip-curled medium if it detects the medium lifting during the curl detection period from the start of rotation of the pick roller 112 until the arrival of the medium is detected by the second medium sensor 116. In this case, the media transport device 100 determines that the medium is not a bound medium, regardless of whether or not the medium lifting is detected during the bound medium detection period. This enables the media transport device 100 to appropriately distinguish and detect tip-curled mediums and bound mediums.

[0097] Furthermore, the media transport device 100 determines that a medium is a wrinkled medium if it detects the medium lifting more than a predetermined number of times during the wrinkle detection period, which is after the curl detection period and before the binding medium detection period. In this case, the media transport device 100 determines that the medium is not a binding medium, regardless of whether or not the medium lifting is detected during the binding medium detection period. This enables the media transport device 100 to appropriately distinguish and detect wrinkled medium and binding medium.

[0098] Furthermore, the media transport device 100 does not determine whether the media is a bound medium after the bound medium detection period has elapsed. This prevents the media transport device 100 from mistakenly determining that a bound medium has been fed when a rear-end curled medium is fed.

[0099] Furthermore, in the media transport device 100, the horseshoe-shaped sensor 113b detects the floating of the media by detecting the rise of the arm 113a, which is positioned to rise in response to the floating of the media. This enables the media transport device 100 to reliably detect the floating of the media.

[0100] Furthermore, in the media transport device 100, the arm 113a is configured to block light from the light-emitting element 113e of the horseshoe-shaped sensor 113b when it is not raised, and to allow light from the light-emitting element 113e to pass to the light-receiving element 113f when it is raised. As a result, if the light-emitting element 113e is unable to emit light properly, or if the light-receiving element 113f is unable to detect light properly, the lifting will not be detected, and in the judgment process, it will be determined that the media is being transported normally. Therefore, the media transport device 100 will not stop transporting when there is an abnormality in the light-emitting element 113e or the light-receiving element 113f, thereby improving user convenience. Note that the arm 113a may also be configured to block light from the light-emitting element 113e of the horseshoe-shaped sensor 113b when it is raised, and to allow light from the light-emitting element 113e to pass to the light-receiving element 113f when it is not raised.

[0101] Furthermore, in the media transport device 100, the lifting sensor 113 is provided on the outside of the pick roller 112 and the feed roller 114 in the width direction A4. This enables the media transport device 100 to reliably detect the lifting of typical bound media.

[0102] Figure 15 is a diagram illustrating the transport path inside the medium transport device 200 according to another embodiment. The medium transport device 200 has a lift sensor 213 instead of a lift sensor 113.

[0103] The lift sensor 213 is positioned within the first housing 101, downstream of the pick roller 112 and upstream of the feed roller 114 in the media transport direction A2, and outside in the width direction A4 relative to the pick roller 112 and the feed roller 114. The lift sensor 213 has a distance measuring sensor. The distance measuring sensor is provided above the media transport path and detects the lift of the media by measuring the distance to the media. The distance measuring sensor includes a light-emitting element and a light-receiving element. The light-emitting element is an LED or the like, and emits light toward the media being fed. The light-receiving element receives light emitted from the light-emitting element and reflected by the media being fed. The distance measuring sensor measures the distance to the media based on the time from when the light-emitting element emits light until the light-receiving element detects the light. The distance measuring sensor detects the lift of the media when the measured distance is less than or equal to a predetermined distance. The predetermined distance is set to the distance from the distance measuring sensor to the maximum height to which the media can bend during media feeding, minus a margin. The lift sensor 213 generates and outputs an electrical signal corresponding to the detected distance as a lift detection signal. The lift sensor 213 may have multiple distance measuring sensors to detect lift of the medium occurring at any location between the upstream side of the roller nip 112a of the pick roller 112 and the downstream side of the roller nip 114a of the feed roller 114 and the brake roller 115.

[0104] Furthermore, in the above-described embodiment, the feed roller 114 was positioned above the brake roller 115 to feed the medium placed on the mounting base 103 sequentially from the top. However, the feed roller may be positioned below the brake roller so that the medium placed on the mounting base is fed sequentially from the bottom.

[0105] Figure 16 shows a schematic configuration of the processing circuit 350 in a media transport device according to another embodiment. The processing circuit 350 is used in place of the processing circuit 150 of the media transport device 100 and performs media reading processing. The processing circuit 350 includes a control circuit 351 and a determination circuit 352, etc. Each of these parts may be composed of an independent integrated circuit, microprocessor, firmware, etc.

[0106] The control circuit 351 is an example of a control unit and has the same functions as the control unit 151. The control circuit 351 receives operation signals from the operating device 105, first medium signals from the first medium sensor 111, and determination results from the determination circuit 352, and controls the motor 131 based on the received signals and determination results. The control circuit 351 also receives input images from the imaging device 119, stores them in the storage device 140, and transmits them to the information processing device via the interface device 132.

[0107] The determination circuit 352 is an example of a determination unit and has the same functions as the determination unit 152. The determination circuit 352 receives a lift detection signal and a second medium signal from the lift sensor 113 and the second medium sensor 116, respectively. Based on the received signals, the determination circuit 352 determines whether the medium is a bound medium or not, and outputs the determination result to the control circuit 351.

[0108] As explained above, the media transport device enables proper detection of the bound media even when using the processing circuit 350.

[0109] Those skilled in the art will understand that various changes, substitutions, and modifications can be made without departing from the spirit and scope of the present invention. For example, the embodiments and modifications described above may be combined as appropriate within the scope of the invention. [Explanation of symbols]

[0110] 100 Media transport device 112 Pick Roller 113 Lifting Sensor 113a Arm 113e Light-emitting element 113f light-receiving element 114 Feeding roller 115 Brake Roller 116 Second medium sensor 151 Control Unit 152 Judgment section

Claims

1. A pick roller for feeding the medium; a separation roller disposed downstream of the pick roller in a medium transport direction; a lift sensor that detects lift of a medium between an upstream side of a roller nip of the pick roller and a downstream side of a roller nip of the separation roller in the transport direction; A medium transport device comprising:

2. The lift sensor detects lift of the outer medium in a direction perpendicular to the conveying direction with respect to the pick roller and the separation roller. The media transport device of claim 1 .

3. the lifting sensor is disposed on the outer side of the pick roller and the separation roller in a direction perpendicular to the conveying direction; The media transport device of claim 2 .

4. The lift sensor is disposed above a medium transport path and detects the lift of the medium by measuring the distance to the medium. The medium transport device according to any one of claims 1 to 3.

5. The device further includes an arm that is disposed above the transport path of the medium and that rises in response to the medium being lifted; The lift sensor detects the lift of the medium by detecting the lift of the arm. The medium transport device according to any one of claims 1 to 3.

6. a width of the arm in a direction perpendicular to the conveying direction is larger than a width of the pick roller in the direction perpendicular to the conveying direction; The medium transport device of claim 5 .

7. a width of the arm in a direction perpendicular to the conveying direction is greater than a width of the separation roller in the direction perpendicular to the conveying direction; The medium transport device according to claim 5 or 6.

8. The arm has a main body and an end portion closer to the lift sensor than the main body, a width of the main body portion in a direction perpendicular to the conveying direction is greater than a width of the end portion in the direction perpendicular to the conveying direction; A medium transport device according to any one of claims 5 to 7.

9. the lift sensor includes a light emitting unit and a light receiving unit that is disposed opposite the light emitting unit across the end of the arm and detects light from the light emitting unit; the end of the arm is formed so as to block light from the light-emitting unit when not raised, and to allow light from the light-emitting unit to pass to the light-receiving unit when raised, The floating sensor detects floating of the medium when the light receiving unit detects light from the light emitting unit. The media transport device of claim 8 .

10. A medium transport path; a discharge tray onto which the medium transported along the transport path is discharged; The floating sensor is disposed between the transport path and the discharge table. A medium transport device according to any one of claims 1 to 9.

11. The floating sensor includes a first sensor and a second sensor each for detecting floating of the medium. A medium transport device according to any one of claims 1 to 10.

12. the first sensor detects lifting of the medium on one outer side in a direction perpendicular to the transport direction with respect to the pick roller and the separation roller; the second sensor detects lifting of the medium on the outer side of the other of the pick roller and the separation roller in a direction perpendicular to the transport direction. The media transport device of claim 11.

13. A processing unit that executes an abnormality process when the floating sensor detects the floating of the medium. A media transport device according to any one of claims 1 to 12.

14. a medium sensor disposed downstream of the separation roller in the transport direction and detecting the medium; the processing unit executes the abnormality process when the floating sensor detects the medium being floating within a first predetermined period after the medium sensor detects the medium. The media transport device of claim 13.

15. when floating of the medium is detected during a second predetermined period from the start of rotation of the pick roller to the detection of the medium by the media sensor, the processing unit does not execute the abnormality processing regardless of whether floating of the medium is detected during a first predetermined period after the detection of the medium by the media sensor. The media handling device of claim 14.

16. the processing unit does not execute the abnormality processing when the floating of the medium is detected a predetermined number of times or more after a second predetermined period has elapsed from the start of rotation of the pick roller before the medium is detected by the media sensor and before a first predetermined period has elapsed after the medium sensor detects the medium. The medium transport device according to claim 14 or 15.

17. the processing unit does not execute the abnormality process after a first predetermined period has elapsed after the medium sensor detects the medium. A media transport device according to any one of claims 14 to 16.

18. The pick roller feeds the media, a separation roller disposed downstream of the pick roller in a medium transport direction separates the medium; a lift sensor detects lift of the medium between an upstream side of the roller nip of the pick roller and a downstream side of the roller nip of the separation roller in the transport direction; A medium transport method comprising:

Images