Media supply device and image forming apparatus

Abstract

To obtain a medium supply device which can precisely detect a plurality of mediums imaged by an imaging part by comparing with the case of irradiating a medium with light only from the same position at one point in a vertical direction.SOLUTION: A medium supply device 10 has a loading part 12 on which a piece of paper P can be loaded in a vertical direction, a supply part 14 which levitates and separated a plurality of pieces of paper P by supplying air to the plurality of pieces of paper P loaded on the loaded part 12, a delivery part 16 which successively feeds the piece of paper P levitated and separated by the supply part 14, a camera 18 which images a state that the piece of paper P is being levitated and separated by the supply part 14, and a light irradiation part 22 which irradiates an end on the imaging side of the piece of paper P with light by the camera 18 from a plurality of different positions in the vertical direction.SELECTED DRAWING: Figure 5

Description

[[Technical Field]]

[0001] The present invention relates to a medium feeding device and an image forming apparatus. [[Background Art]]

[0002] The following Patent Document 1 discloses a sheet feeding device comprising: an arrangement portion on which a sheet bundle formed by stacking a plurality of sheets in the vertical direction can be placed; an air blowing means that blows air onto the sheet bundle placed on the arrangement portion to float sheets positioned in an upper layer of the sheet bundle; a suction / conveyance mechanism that is provided above the arrangement portion, sucks the sheet floated by the air blowing means, and conveys the sheet in a predetermined conveyance direction; an imaging means that images the sheet floated by the air blowing means; and an illumination means that irradiates light a plurality of times onto the sheet floated by the air blowing means during one exposure operation of the imaging means. [[Prior Art Documents]] [[Patent Documents]]

[0003] [[Patent Document 1]] Japanese Patent No. 6145793 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0004] An object of the present invention is to obtain a medium feeding device and an image forming apparatus capable of accurately detecting a plurality of media imaged by an imaging unit, compared with a case where the medium is irradiated only with light from the same position at one location in the vertical direction. [[Means for Solving the Problem]]

[0005] A media supply device according to the first embodiment includes a loading section on which media can be loaded in the vertical direction, a supply section that supplies air to a plurality of media loaded in the loading section to levitate and separate the plurality of media, a transport section that sequentially delivers the media levitated and separated by the supply section, a shooting section that photographs the state in which the media are levitated and separated by the supply section, and a light irradiation section that irradiates light from a plurality of different positions in the vertical direction onto the end of the media that is photographed by the shooting section. It holds.

[0006] A media supply device according to a second embodiment is a media supply device according to a first embodiment, further comprising at least one processor, wherein the processor determines, based on the image captured by the imaging unit, that there is a concern about clogging or double feeding of the media, and changes the amount of air supplied by the supply unit.

[0007] A media supply device according to the third embodiment is a media supply device according to the first embodiment, further comprising at least one processor, wherein the processor acquires the captured image by changing the vertical position in which the light irradiation unit irradiates the medium with light for each captured image captured by the imaging unit.

[0008] The medium supply device according to the fourth embodiment is the medium supply device according to the first embodiment, wherein the light irradiation unit has a plurality of illumination units arranged at different positions in the vertical direction.

[0009] The media supply device according to the fifth embodiment is the media supply device according to the fourth embodiment, wherein the plurality of illumination units are arranged offset in a direction toward or away from the end of the medium that is photographed by the photographing unit.

[0010] The media supply device according to the sixth embodiment is the media supply device according to the fourth embodiment, wherein the imaging unit is positioned opposite to the plurality of media that are levitated and separated by the supply unit, and the illumination unit is positioned at least above the imaging unit in the vertical direction.

[0011] The media supply device according to the seventh embodiment is the media supply device according to the sixth embodiment, wherein the plurality of illumination units are arranged on the upper and lower sides in the vertical direction relative to the imaging unit.

[0012] The media supply device according to the eighth embodiment is the media supply device according to the sixth embodiment, wherein the imaging unit is located in the central part in the vertical direction, facing the plurality of media that are levitated and separated by the supply unit.

[0013] The media supply device according to the ninth embodiment is the media supply device according to the third embodiment, wherein the processor excludes areas unsuitable for identifying the media from the relative position between the position where the light irradiation unit irradiates light in the vertical direction and the media, and detects the edges of the media in the captured image corresponding only to the areas in which the media can be identified.

[0014] The media supply device according to the tenth embodiment is the media supply device according to the third embodiment, wherein the processor compares the positions of the edges of the media detected for each captured image, and if the difference in the positions of the edges of the media is less than or equal to a threshold, it is detected as the same media, and if it is greater than the threshold, it is detected as a new media.

[0015] The media supply device according to the 11th embodiment is the media supply device according to the 10th embodiment, wherein the processor creates a filter that is thickened by a width in the thickness direction determined from the center position of the edge of the medium detected in the nth captured image, and determines that it is the same medium when the center position of the edge of the medium detected in the (n+1)th captured image falls inside the filter, and updates the filter with a new filter that is thickened by a width in the thickness direction determined from the center position of the edge of the medium in the (n+1)th captured image.

[0016] The image forming apparatus according to the twelfth embodiment comprises a media supply device described in any one of the first to eleventh embodiments, and an image forming unit that forms an image on the medium supplied by the media supply device. [Effects of the Invention]

[0017] According to the medium feeding apparatus according to the first aspect, a plurality of media imaged by an imaging unit can be detected with higher accuracy, compared to a case where the medium is irradiated with light only from the same single position in the vertical direction.

[0018] According to the medium feeding apparatus according to the second aspect, jamming or double feeding of media can be suppressed, compared to a case where the supply amount of air is always constant.

[0019] According to the medium feeding apparatus according to the third aspect, a plurality of media imaged by an imaging unit can be detected with higher accuracy, compared to a case where a plurality of captured images are acquired by irradiating the medium with light from the same position in the vertical direction.

[0020] According to the medium feeding apparatus according to the fourth aspect, the structure is simple, compared to a case where light is irradiated onto the medium from different positions in the vertical direction using one light irradiation unit.

[0021] According to the medium feeding apparatus according to the fifth aspect, a plurality of media imaged by an imaging unit can be detected with higher accuracy, compared to a case where a plurality of irradiation units are arranged at the same distance with respect to an end portion on the imaging side of the medium by the imaging unit.

[0022] According to the medium feeding apparatus according to the sixth aspect, a plurality of media imaged by an imaging unit can be detected with higher accuracy, compared to a case where an illumination unit is arranged only on the lower side in the vertical direction relative to the imaging unit.

[0023] According to the medium feeding apparatus according to the seventh aspect, a plurality of media imaged by an imaging unit can be detected with higher accuracy, compared to a case where an illumination unit is arranged only on the upper side in the vertical direction relative to the imaging unit.

[0024] According to the medium feeding apparatus according to the eighth aspect, a plurality of media imaged by an imaging unit can be detected with higher accuracy, compared to a case where the imaging unit is arranged on the lower side in the vertical direction of the plurality of media levitated and separated by a feeding unit.

[0025] According to the medium feeding device of the ninth aspect, a plurality of media can be detected with higher accuracy compared to a case where the edge of a medium is detected from the entire captured image.

[0026] According to the medium feeding device of the tenth aspect, a plurality of media can be detected with higher accuracy compared to a case where the identity of media detected for each captured image is not determined.

[0027] According to the medium feeding device of the eleventh aspect, a plurality of media can be detected with higher accuracy compared to a case where the same filter is always used.

[0028] According to the image forming apparatus of the twelfth aspect, a plurality of media captured by the imaging unit can be detected with higher accuracy compared to a case where the medium is irradiated with light from the same position at one point in the vertical direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] [Figure 1] (A) is a front view showing a part of the medium feeding device according to the first embodiment, and (B) is a schematic diagram showing an example of an image forming apparatus including the medium feeding device. [Figure 2] It is a plan view showing a part of the medium feeding device according to the first embodiment. [Figure 3] It is a block diagram showing the hardware configuration of the medium feeding device according to the first embodiment. [Figure 4] It is a block diagram showing an example of the functional configuration of the control device of the medium feeding device according to the first embodiment. [Figure 5] It is a configuration diagram showing a first example of an illumination unit that is turned on when an edge of a sheet is photographed by a camera in the medium feeding device according to the first embodiment. [Figure 6] It is a configuration diagram showing a second example of an illumination unit that is turned on when an edge of a sheet is photographed by a camera in the medium feeding device according to the first embodiment. [Figure 7] It is a configuration diagram showing a third example of an illumination unit that is turned on when an edge of a sheet is photographed by a camera in the medium feeding device according to the first embodiment. [Figure 8] This is a configuration diagram showing a fourth example of an illumination unit that lights up when the edge of the paper is photographed by a camera in the media supply device according to the first embodiment. [Figure 9] (A) is a diagram showing the actual positions of multiple sheets of paper in the media supply device according to the first embodiment, (B) is a diagram showing an example of the first frame image in which multiple sheets of paper are photographed, and (C) is a diagram showing an example of the second frame image in which multiple sheets of paper are photographed. [Figure 10] (A) is a diagram showing an example of creating a filter based on the image of the first frame, and (B) is a diagram showing an example of creating a filter based on the image of the second frame. [Figure 11] (A) is a diagram showing an example of a state in which the paper floats and separates well, (B) is a diagram showing an example of a state in which the paper floats and separates poorly, and (C) is a diagram showing another example of a state in which the paper floats and separates poorly. [Figure 12] This flowchart shows the processing flow of the media supply device according to the first embodiment. [Figure 13] This figure shows an image taken of the edge of a sheet of paper in the media supply device of the comparative example. [Modes for carrying out the invention]

[0030] The following describes embodiments for carrying out the present invention. In the following description, the direction indicated by arrow X in the drawings is the device width direction, and the direction indicated by arrow Y is the device height direction. The direction perpendicular to the device width direction and the device height direction (arrow Z direction) is the device depth direction.

[0031] [First Embodiment] Figure 1(A) shows a part of the media supply device 10 according to the first embodiment, and Figure 1(B) shows an example of an image forming apparatus 100 equipped with the media supply device 10.

[0032] <Configuration of an image forming apparatus> As shown in Figure 1(B), the image forming apparatus 100 includes an image forming unit 102 that forms an image on paper P, which is an example of a medium, and a medium supply device 10 that supplies paper P to the image forming unit 102 one sheet at a time. Although not shown in the figure, the image forming apparatus 100 is equipped with a transport means for transporting paper P to the image forming position of the image forming unit 102. The configuration and arrangement of the image forming unit 102 and the transport means are not particularly limited. In addition, the medium supply device 10 may be optionally attached to the main body of the image forming apparatus.

[0033] <Configuration of the media supply device> (Overall structure) As shown in Figures 1(A) and (B), the media supply device 10 includes a loading section 12 on which paper P can be stacked vertically, and a supply section 14 that supplies air to the multiple sheets of paper P stacked in the loading section 12 to levitate and separate the paper P. The media supply device 10 also includes a delivery section 16 that sequentially feeds out the paper P that has been levitated and separated by the supply section 14. The delivery section 16 is an example of a transport section. The media supply device 10 also includes a camera 18, which is an example of a photography section that photographs the state in which the paper P is levitated and separated by the supply section 14, and a light irradiation section 22 that irradiates light onto the end of the paper P on the side that is photographed by the camera 18. Furthermore, the media supply device 10 includes a control device 50 that controls the operation of each section. The control device 50 is an example of a processor.

[0034] (Loading section) As shown in Figure 1(B), the loading section 12 is equipped with a plate-like body 12A on which multiple sheets of paper P can be loaded. Although not shown in the figure, the media supply device 10 is equipped with a lifting device that raises and lowers the plate-like body 12A vertically. The lifting device raises the plate-like body 12A so that the position of the uppermost sheet of paper P loaded on the upper side of the plate-like body 12A is at a predetermined height.

[0035] As shown in Figure 2, the media supply device 10 is provided with side guides 20 that regulate the position of the sides of the paper P loaded in the loading section 12 in the width direction (arrow Z direction in this example). The side guides 20 are located on the upper side of the loading section 12 and are provided on both sides of the paper P in the width direction (arrow Z direction). As an example, the side guides 20 are mounted on the loading section 12 so as to be slidable in the depth direction of the device (arrow Z direction). The side guides 20 can be slid in the depth direction of the device (arrow Z direction) according to the size of the paper P. The range of movement of the side guides 20 is limited by a stopper (length of guide slit) (not shown) so as not to interfere with the delivery section 16.

[0036] (Supply Department) As shown in Figures 1(A) and 2, the supply unit 14 is equipped with an air outlet 30 that blows air from the side of the paper P in the width direction (arrow Z direction) to the upper side of the stacking unit 12. The air outlet 30 is positioned opposite the top of the multiple sheets of paper P stacked on top of the plate-like body 12A. The supply unit 14 levitates and separates the multiple sheets of paper P stacked on the plate-like body 12A of the stacking unit 12 by blowing air from the air outlet 30 between the multiple sheets of paper P.

[0037] The supply unit 14 includes a duct 32 connected to the outlet 30 and a fan 34 located upstream of the airflow direction in the duct 32 (see Figure 2). In the supply unit 14, the rotation of the fan 34 supplies air through the duct 32 to the outlet 30, and the air is blown out from the outlet 30 to the upper side of the loading unit 12.

[0038] Although not shown in the diagram, the air outlets 30 are provided on both sides of the paper P in the width direction (arrow Z direction). As an example, air outlets 30 are provided on the side guides 20 on both sides of the paper P in the width direction (arrow Z direction). The duct 32 is branched into two downstream of the fan 34 in the direction of airflow, and air outlets 30 are provided at the downstream ends of each branched portion of the duct 32.

[0039] (Transmission section) As shown in Figure 1(A), the delivery unit 16 transports the sheets of paper P loaded on the upper side of the plate-shaped body 12A of the loading unit 12 one by one in the direction of arrow A, that is, to the right in the width direction of the device (to the right in the direction of arrow X). The delivery unit 16 includes a delivery roll (feed roll) 36 that delivers the uppermost sheets of paper P on the upper side of the loading unit 12 one by one, and a suction unit 40 that is positioned inside the delivery roll 36 in the width direction of the device (to the left in the direction of arrow X). The suction unit 40 suctions the uppermost sheet of paper P. Furthermore, the delivery unit 16 includes a pair of transport rolls 38 that transport the sheets of paper P delivered by the delivery roll 36.

[0040] For example, in the feeding unit 16, the paper P held by the suction unit 40 comes into contact with the feeding roll 36, causing the paper P to be fed out from the feeding roll 36 in the direction of arrow A, and then transported in the direction of arrow A by the transport roll 38.

[0041] (camera) Camera 18 captures the levitation and separation of the edges of the paper P. As shown in Figures 1 and 2, camera 18 is located on the side of the paper P in the width direction (arrow Z direction). Camera 18 is positioned opposite the edges of the paper P loaded on the plate-like body 12A in the width direction (arrow Z direction). This allows camera 18 to capture the levitation and separation of the paper P from the outside of the edges of the paper P in the width direction. As an example, camera 18 is provided on both sides of the edges of the paper P in the width direction (arrow Z direction).

[0042] For example, the camera 18 is positioned on the upper side of the side guide 20, near the downstream end of the side guide 20 in the direction of paper feeding P (direction of arrow A).

[0043] (Light-irradiated area) The light irradiation unit 22 irradiates light onto the edge of the paper P when the camera 18 photographs the edge of the paper P. As shown in Figure 5, the light irradiation unit 22 irradiates light onto the edge of the paper P on the side photographed by the camera 18 from multiple different positions in the vertical direction. As an example, the light irradiation unit 22 has multiple illumination units 24 arranged at different positions in the vertical direction. In the first embodiment, there are four illumination units 24, comprising a first illumination unit 24A, a second illumination unit 24B, a third illumination unit 24C, and a fourth illumination unit 24D arranged from the top to the bottom in the vertical direction.

[0044] The multiple illumination units 24 are arranged offset from the edge of the paper P on the side photographed by the camera 18, either approaching or moving away from it. In the first embodiment, the uppermost first illumination unit 24A and the lowermost fourth illumination unit 24D are arranged on the side approaching the edge of the paper P on the side photographed by the camera 18. The second illumination unit 24B and the third illumination unit 24C in the middle of the vertical direction are arranged offset from the edge of the paper P on the side photographed by the camera 18, compared to the first illumination unit 24A and the fourth illumination unit 24D. In a plan view of the media supply device 10, the second illumination unit 24B and the third illumination unit 24C are arranged to overlap on the side closer to the edge of the paper P in the width direction, while the first illumination unit 24A and the fourth illumination unit 24D are arranged to overlap on the side away from the edge of the paper P in the width direction.

[0045] As shown in Figure 5, the camera 18 is positioned opposite the multiple sheets of paper P that are lifted and separated by air from the supply unit 14. For example, the camera 18 is positioned in the vertical center opposite the multiple sheets of paper P that are lifted and separated by air from the supply unit 14. Here, the vertical center opposite the multiple sheets of paper P refers to the center of the range in which the multiple sheets of paper P disperse when a predetermined amount of air is blown onto them. The first illumination unit 24A and the second illumination unit 24B are positioned above the camera 18 in the vertical direction. The third illumination unit 24C and the fourth illumination unit 24D are positioned below the camera 18 in the vertical direction.

[0046] As shown in Figures 5 to 8, the light illuminator 22 illuminates the edge of the paper P on the side photographed by the camera 18 from multiple different positions in the vertical direction by lighting up the first illumination unit 24A, the second illumination unit 24B, the third illumination unit 24C, and the fourth illumination unit 24D in a predetermined order. The first illumination unit 24A, the second illumination unit 24B, the third illumination unit 24C, and the fourth illumination unit 24D have similar configurations, and when there is no need to distinguish between these four, they will be described as illumination unit 24.

[0047] (Hardware configuration of the media supply device) Figure 3 is a block diagram showing the hardware configuration of the equipment mounted on the media supply device 10. As shown in Figure 3, the media supply device 10 includes the control device 50, the camera 18, the supply unit 14, and the light illumination unit 22, as described above. The light illumination unit 22 includes a first illumination unit 24A, a second illumination unit 24B, a third illumination unit 24C, and a fourth illumination unit 24D.

[0048] The control unit 50 has a CPU (Central Processing Unit) 51, ROM (Read Only Memory) 52, RAM (Random Access Memory) 53, storage 54, and an input / output interface 55. Each component is connected to the others via a bus 59 so that they can communicate with each other.

[0049] The CPU 51 is a central processing unit that executes various programs and controls various parts. The CPU 51 is an example of a processor. Specifically, the CPU 51 reads a program from the ROM 52 or storage 54 and executes the program using the RAM 53 as a working area. The CPU 51 controls each of the above components and performs various calculations according to the program recorded in the ROM 52 or storage 54. In this embodiment, the ROM 52 or storage 54 stores a detection processing program.

[0050] ROM 52 stores various programs and data. RAM 53 temporarily stores programs or data as a working area. Storage 54 consists of an HDD (Hard Disk Drive) or SSD (Solid State Drive) and stores various programs, including the operating system, and various data. The printer driver program is stored in storage 54. The CPU 51 reads the printer driver program from storage 54 and functions as a printer driver by executing the program.

[0051] The input / output interface 55 is an interface for communicating with each device mounted on the media supply device 10. The control device 50 is connected to the camera 18, the supply unit 14, and the light illumination unit 22 via the input / output interface 55. Alternatively, the camera 18, the supply unit 14, and the light illumination unit 22 may be directly connected via the bus 59.

[0052] (Functional configuration of the control unit) Figure 4 is a block diagram showing an example of the functional configuration of the control device 50.

[0053] As shown in Figure 4, the control device 50 has a functional configuration consisting of a light irradiation control unit 71, an image acquisition unit 72, a paper calculation unit 73, a paper state determination unit 74, and an air supply amount changing unit 75. This is achieved by the CPU 51 reading a detection processing program stored in the ROM 52 or storage 54, loading it into the RAM 53, and executing it.

[0054] The light irradiation control unit 71 controls the on and off of multiple illumination units 24 in the light irradiation unit 22. More specifically, the light irradiation control unit 71 controls the on and off of the first illumination unit 24A, the second illumination unit 24B, the third illumination unit 24C, and the fourth illumination unit 24D, which constitute the multiple illumination units 24, thereby changing the vertical position of the light irradiating the paper P (see Figures 5 to 8). In the first embodiment, the vertical position of the light irradiating the paper P by the multiple illumination units 24 is changed for each frame captured by the camera 18. One frame is an example of one captured image. As an example, the light irradiation control unit 71 lights up one of the multiple illumination units 24 (one of the first illumination unit 24A, the second illumination unit 24B, the third illumination unit 24C, and the fourth illumination unit 24D) in a predetermined order, and turns off the other illumination units 24 when one illumination unit 24 is turned on.

[0055] The image acquisition unit 72 acquires images of the edges of the paper P in the width direction (arrow Z direction) captured by the camera 18. The image acquisition unit 72 acquires multiple images by changing the vertical position of the multiple illumination units 24 that illuminate the paper P for each frame captured by the camera 18. For example, in the media supply device 10, the image acquisition unit 72 acquires at least four images by capturing the edges of the paper P with the camera 18 each time one of the first illumination unit 24A, second illumination unit 24B, third illumination unit 24C, and fourth illumination unit 24D lights up in a predetermined order.

[0056] The paper calculation unit 73 calculates the position of the edge of the paper P in the width direction (arrow Z direction) based on the captured image of the edge of the paper P in the width direction (arrow Z direction) captured by the camera 18. The paper calculation unit 73 excludes the undeterminable area 82 (see Figures 5 to 8) which is unsuitable for identifying the paper P, based on the relative position of the position where the light irradiation unit 22 irradiates light in the vertical direction and the paper P, and detects the edge of the paper P in the captured image corresponding only to the determinable area 80 (see Figure 5, etc.) where the paper P can be identified. The undeterminable area 82 is an example of an area unsuitable for identifying the paper P, and the determinable area 80 is an example of an area where the paper P can be identified. The paper calculation unit 73 detects the levitation and separation state of the edge of the paper P in the width direction by calculating the position of the edge of the paper P in the width direction in the determinable area 80. The method for detecting the levitation and separation state of the edge of the paper P in the width direction will be described later.

[0057] The paper condition determination unit 74 determines whether there is a risk of paper jamming or double feeding based on the floating and separation state of the edges of the paper P in the width direction. The conditions for determining whether there is a risk of paper jamming or double feeding are stored in the storage 54 in advance. These conditions will be described later.

[0058] The air supply rate adjustment unit 75 changes the amount of air supplied by the supply unit 14. For example, the air supply rate adjustment unit 75 changes the amount of air supplied by the supply unit 14 when it determines that there is a concern about paper jamming or double feeding of paper P.

[0059] For example, if the levitation and separation of the paper P is insufficient (the number of paper P sheets being levitated and separated is small), the air supply amount changing unit 75 increases the amount of air supplied by the supply unit 14. Also, for example, if the number of paper P sheets being levitated is too large and multiple sheets of paper P are bundled together and not sufficiently separated, the air supply amount changing unit 75 decreases the amount of air supplied by the supply unit 14. For example, changing the amount of air supplied by the supply unit 14 is done by changing the rotation speed of the fan 34.

[0060] (Configuration and problems of the media supply device of the comparative example) Here, we will explain the configuration and problems of the comparative example media supply device.

[0061] The media supply device of the comparative example, although not shown in the diagram, includes a single illumination unit with a fixed vertical position and a camera. The camera then captures the edges of the paper P in the width direction while light is irradiated from the illumination unit.

[0062] Generally, in a configuration where multiple sheets of paper P are levitated and separated by air blown from a supply unit, the sheets of paper P tend to move by several millimeters in the depth direction opposite to the camera. For this reason, in the media supply device of the comparative example, when the edges of multiple sheets of paper P are photographed by the camera while light is irradiated from a single illumination unit, the brightness of the edges of the multiple sheets of paper P in the vertical direction may change.

[0063] Figure 13 shows an image captured by a camera of the widthwise edge of a sheet of paper P in a comparative example media supply device. As shown in Figure 13, in the first area 302 of the captured image, the sheet of paper P that has moved to the back in the depth direction relative to the camera is darker than the other sheets of paper P. This is because the sheet of paper P that has moved to the back in the depth direction relative to the camera is hidden by the other sheets of paper P directly above or below it, making it difficult for the light from the illumination unit to reach it, and thus the sheet of paper P appears darker than the other sheets of paper P. For this reason, when detecting the levitation and separation state of multiple sheets of paper P, the sheet of paper P in the first area 302 may not be detected.

[0064] Furthermore, as shown in Figure 13, in the second area 304 of the captured image, the illumination unit shines light from the front side of the paper P, causing the top surface of the paper P to appear illuminated. This can sometimes lead to misidentification as a thick paper P. Also, depending on the camera position, illuminating the paper P from the front side may cause the bottom surface of the paper P to appear illuminated, which can also lead to misidentification as a thick paper P.

[0065] In contrast, the media supply device 10 of the first embodiment performs the following process to detect the edges of the paper P in order to suppress false detection of the paper P.

[0066] (Process to detect the edge of paper P) In the media supply device 10, multiple images are acquired by photographing the edges of the paper P with a camera 18 while changing the vertical position of the multiple illumination units 24 that irradiate the paper P with light. Furthermore, the CPU 51 of the control device 50 performs processing to detect the position of the edges of the paper P in the width direction (arrow Z direction) based on the multiple images (for example, by image analysis).

[0067] Figures 5 to 8 schematically show the state of multiple sheets of paper P as captured by the camera 18 when the lighting positions of multiple vertical lighting units 24 are changed. In Figures 5 to 8, the position of each sheet of paper P from the top is indicated in parentheses to make it easier to identify which sheet of paper P is being photographed.

[0068] As shown in Figure 5, when the fourth illumination unit 24D at the bottom in the vertical direction is lit, the 2nd, 4th, 5th, 6th, and 8th sheets of paper P from the top are recognized as edges of the paper P. The 1st, 3rd, and 7th sheets of paper P are shifted towards the back in the depth direction relative to the camera 18 and are difficult to detect. In addition, the 9th and 10th sheets of paper P may appear to be illuminated on the top or bottom, resulting in false detection. For this reason, when the fourth illumination unit 24D at the bottom in the vertical direction is lit, the CPU 51 sets the 1st to 8th sheets of paper P to the discriminable area 80 and the 9th to 10th sheets of paper P to the undiscriminable area 82.

[0069] As shown in Figure 6, when the second third illumination unit 24C from the bottom in the vertical direction is lit, the 1st, 2nd, 4th, 5th, 6th, and 7th sheets of paper P from the top are recognized as edges of the paper P. The 3rd sheet of paper P is shifted towards the back in the depth direction relative to the camera 18 and is difficult to detect. In addition, the 8th, 9th, and 10th sheets of paper P may appear as illuminated on the top or bottom, resulting in false detection. For this reason, when the second third illumination unit 24C from the bottom in the vertical direction is lit, the CPU 51 sets the 1st to 7th sheets of paper P to the discriminable area 80 and the 8th to 10th sheets of paper P to the undiscriminable area 82.

[0070] As shown in Figure 7, when the second illumination unit 24B from the top in the vertical direction is lit, the 3rd, 4th, 5th, 6th, 8th, 9th and 10th sheets of paper P from the top are recognized as edges of the paper P. The 7th sheet of paper P is shifted towards the back in the depth direction relative to the camera 18 and is difficult to detect. In addition, the 1st and 2nd sheets of paper P may appear to be illuminated on the top or bottom, resulting in false detection. For this reason, when the second illumination unit 24B from the top in the vertical direction is lit, the CPU 51 sets the 3rd to 10th sheets of paper P to the discriminable area 80 and the 1st and 2nd sheets of paper P to the undiscriminable area 82.

[0071] As shown in Figure 8, when the first illumination unit 24A at the top in the vertical direction is lit, the 1st, 2nd, 4th, 5th, 6th, and 8th sheets of paper P from the top are recognized as edges of the paper P. The 3rd and 7th sheets of paper P are shifted towards the back in the depth direction relative to the camera 18 and are difficult to detect. Also, the 9th and 10th sheets of paper P are hidden by the 8th sheet of paper P and are difficult to detect. Because the first illumination unit 24A is positioned above the 1st sheet of paper P in the vertical direction when multiple sheets of paper P are levitated and separated, light is not emitted from the front side of the paper P, and the top or bottom surface of the paper P is suppressed from being illuminated and captured. For this reason, when the first illumination unit 24A at the top in the vertical direction is lit, the CPU 51 sets the 1st to 10th sheets of paper P to the discriminable area 80. As shown in Figures 5 to 8, the discriminable area 80 and the indiscriminate area 82 are determined based on the relative position between the position where light is irradiated vertically by the multiple illumination units 24 of the light irradiation unit 22 and the paper P.

[0072] Figure 9(A) shows an example of the actual positions of multiple sheets of paper P. Figure 9(B) shows an example of the first frame image when the camera 18 photographs multiple sheets of paper P, and Figure 9(C) shows an example of the second frame image when the camera 18 photographs multiple sheets of paper P. As shown in Figure 9(A), the first to fifth sheets of paper P are arranged at equal intervals. As shown in Figure 9(B), the third sheet of paper P is not visible in the first frame image. Therefore, the third sheet of paper P is excluded from the first frame image. As shown in Figure 9(C), the fourth sheet of paper P is not visible in the second frame image. Therefore, the fourth sheet of paper P is excluded from the second frame image.

[0073] Figures 10(A) and (B) show an example of the process flow for detecting the edges of the paper P by the CPU 51 in the case shown in Figure 9. As shown in Figure 10(A), in the first frame of the image, the CPU 51 excludes the third sheet of paper P and detects the center positions of the first, second, fourth, and fifth sheets of paper P (i.e., the center coordinates in the thickness direction of the paper P). Furthermore, for the first, second, fourth, and fifth sheets of paper P, the CPU 51 creates a filter 90 that is widened by a predetermined width in the thickness direction from the center position of the edge of the paper P.

[0074] As shown in Figure 10(B), the CPU 51 excludes the fourth sheet of paper P in the second frame image and detects the center positions of the first, second, third, and fifth sheets of paper P (i.e., the center coordinates in the thickness direction of the paper P). The CPU 51 determines that the first, second, third, and fifth sheets of paper P are the same sheet of paper P if their center positions fall within the filter 90 created based on the first frame image (see the diagram on the left in Figure 10(B)).

[0075] The CPU 51 performs an AND operation between the filter 90 shown on the right side of Figure 10(A) and the center position of the paper P shown on the left side of Figure 10(B) to calculate the new center position of the paper P. More specifically, as shown in Figure 10(B), in the second frame image, the CPU 51 creates a filter 90 for the 1st, 2nd, 3rd, and 5th sheets of paper P, which is widened by a predetermined width in the thickness direction from the center position of the edge of the paper P. Furthermore, in the second frame image, the CPU 51 creates a filter 90 at the same position as the filter 90 for the 4th sheet of paper P (see Figure 10(A)) created based on the first frame image. In other words, the filter 90 is updated in the second frame image. The CPU 51 repeats the above process in the order of the frames captured by the camera 18.

[0076] The above detection process can be summarized as follows: The CPU 51 detects the center position of the paper P in the nth frame image (i.e., the center coordinate position in the thickness direction of the paper P) (see Figure 10(A)). Paper P with unclear edges or in the undeterminable area 82 (i.e., paper P whose bottom or top surface may be reflected due to light) is ignored. The nth frame image is an example of the nth captured image. The CPU 51 creates a filter 90 that is widened by a predetermined width in the thickness direction from the center position of the edge of the paper P detected in the nth frame image (see Figure 10(A)).

[0077] The CPU 51 detects the center position of the paper P in the (n+1)th frame image (i.e., the center coordinate position in the thickness direction of the paper P) in the same manner as described above (see Figure 10(B)). The (n+1)th frame image is an example of the (n+1)th captured image. The CPU 51 compares the positions of the edges of the paper P detected for each frame image by the camera 18, and if the difference in the positions of the edges of the paper P is less than or equal to a threshold, it is detected as the same paper P; if it is greater than the threshold, it is detected as a new paper P. In the first embodiment, the CPU 51 determines that it is the same paper P if the center position of the edge of the paper P detected in the (n+1)th frame falls inside the filter 90. The CPU 51 updates the filter 90 to a new filter that is wider by a predetermined width in the thickness direction from the center position of the edge of the paper P in the (n+1)th frame image (see Figure 10(B)). If the paper P is excluded in the (n+1)th frame image, the CPU 51 creates a filter 90 at the same position as the filter 90 for the paper P in the nth frame image. The CPU 51 detects the position of the edge of the paper P by repeating the above process, that is, it performs image analysis of the edge of the paper P.

[0078] (Conditions for determining the state of paper P) Next, the conditions for the control device 50 to determine whether or not there is a concern about a paper jam or double feeding of paper P will be described.

[0079] The CPU 51 of the control device 50 detects the floating and separated state of the edges of the paper P by detecting the position of the edges of the paper P through the above detection process. Furthermore, the CPU 51 determines whether there is a concern about a paper jam or double feed. The condition under which it is determined that there is a concern about a paper jam or double feed is when a number of paper P less than or equal to a predetermined first threshold (e.g., 4 sheets) is floating. The condition under which it is determined that there is a concern about a paper jam or double feed is when a number of paper P greater than or equal to a predetermined second threshold (e.g., 3 sheets) is in a bundle state that is not separated. In such cases, the CPU 51 determines that there is a concern about a paper jam or double feed. The above first and second thresholds can be changed.

[0080] Figures 11(A) to (C) show an example of the state of the paper P when air is blown from the outlet 30 of the supply unit 14 onto the paper P loaded on the plate-shaped body 12A of the loading unit 12. In the first example shown in Figure 11(A), about 10 sheets of paper P on the upper side are separated and floating, indicating good floating and separation of the paper P. In this state, even if the paper P is transported sequentially by the delivery unit 16, double feeding of paper P is unlikely to occur. In such cases, based on the above conditions, the CPU 51 determines that there is no concern about paper jamming or double feeding of paper P.

[0081] In the second example shown in Figure 11(B), only about one sheet of paper P is floating, and the floating and separation of the paper P is insufficient. In this state, when the paper P is sequentially transported by the feeding unit 16, there is a concern that a supply failure (i.e., a misfeed) will occur in which the paper P is not supplied smoothly. In such cases, based on the above conditions, the CPU 51 determines that there is a concern about paper jamming or double feeding of the paper P.

[0082] In the third example shown in Figure 11(C), the air is blown out too strongly from the outlet 30, causing the upper part of the paper P to float in a bundle, and the floating and separation of the paper P is insufficient. In this state, there is a concern that double feeding of the paper P may occur when the paper P is sequentially transported by the feeding unit 16. In such cases, based on the above conditions, the CPU 51 determines that there is a concern about paper jamming or double feeding of the paper P.

[0083] <Mechanism and Effects> Next, the operation of the first embodiment will be described.

[0084] Figure 12 is a flowchart showing the flow of the detection process handled by the control device 50. The detection process is performed when the CPU 51 reads the detection process program from the ROM 52 or storage 54, loads it into the RAM 53, and executes it.

[0085] Before the detection process shown in Figure 12 is executed, the user issues a print instruction to the image forming apparatus 100 for printing image data onto paper P. When the image forming apparatus 100 receives the print instruction, the media supply device 10 supplies air via the supply unit 14 to levitate and separate the paper P loaded in the loading unit 12.

[0086] CPU 51 starts supplying paper P (step S201).

[0087] The CPU 51 acquires multiple images captured by the camera 18 showing the edges of the paper P in the width direction (step S202). As shown in Figures 5 to 8, in the media supply device 10, the camera 18 captures the edges of the paper P while changing the vertical position in which light is irradiated onto the paper P by multiple illumination units 24 constituting the light irradiation unit 22. As a result, the CPU 51 acquires multiple images captured by the camera 18 showing the edges of the paper P in the width direction.

[0088] The CPU 51 detects the state of the paper P, that is, the levitation and separation state of the edges of the paper P (step S203). As shown in Figures 5 to 8, the CPU 51 excludes the undeterminable area 82 in multiple captured images and detects the edges of the paper P in the captured images corresponding only to the determinable area 80. As shown in Figures 9 and 10, the CPU 51 performs the edge detection process for the paper P in the order of the captured images taken by the camera 18, based on the flow of the paper P edge detection process. The CPU 51 detects the position of the edges of the paper P by repeating the process shown in Figure 10 (i.e., performs image analysis of the position of the edges of the paper P). As a result, the CPU 51 detects the levitation and separation state of the edges of the paper P.

[0089] The CPU 51 determines whether there is a concern about a paper jam or double feed of paper P (step S204). For example, the CPU 51 determines whether there is a concern about a paper jam or double feed of paper P based on the detection conditions described above.

[0090] If there is no concern about paper jams or double feeding (step S204: NO), the CPU 51 continues the paper supply operation (step S205). In other words, the amount of air supplied by the supply unit 14 is not changed.

[0091] If there is a concern about paper jamming or double feeding (step S204: YES), the CPU 51 changes the amount of air supplied by the supply unit 14 (step S206). This adjusts the buoyancy and separation state of the paper P loaded in the loading unit 12. Furthermore, the CPU 51 returns to the process in step S202. This terminates the processing based on the detection processing program handled by the control device 50.

[0092] Furthermore, after step S206, if a predetermined time has elapsed, the CPU 51 may display an alert indicating a potential paper jam or double feed and stop supplying paper P.

[0093] In the media supply device 10 described above, the light irradiation unit 22 irradiates light onto the edge of the paper P on the side to be photographed by the camera 18 from multiple different positions in the vertical direction, and the camera 18 photographs the state in which the paper P is levitated and separated. Therefore, the media supply device 10 can accurately detect multiple sheets of paper P photographed by the camera 18 compared to the case in which light is irradiated onto the paper from only one same position in the vertical direction. As a result, the number of paper P transport failures is reduced compared to the case in which light is irradiated onto the paper from only one same position in the vertical direction.

[0094] Furthermore, in the media supply device 10, the CPU 51 changes the amount of air supplied by the supply unit 14 when it determines from the image captured by the camera 18 that there is a concern about paper jamming or double feeding. As a result, the media supply device 10 can suppress paper jamming or double feeding compared to when the amount of air supplied is always constant.

[0095] Furthermore, in the media supply device 10, the CPU 51 changes the vertical position from which the light is irradiated onto the paper P by the light irradiation unit 22 for each image captured by the camera 18, thereby acquiring the captured image. As a result, the media supply device 10 can detect multiple sheets of paper P captured by the camera 18 with greater accuracy compared to the case where multiple images are acquired by irradiating the paper from the same vertical position.

[0096] Furthermore, in the media supply device 10, the light irradiation unit 22 has multiple illumination units 24 arranged at different positions in the vertical direction. Therefore, the media supply device 10 has a simpler structure compared to a case where a single light irradiation unit is used to irradiate the paper with light from different positions in the vertical direction.

[0097] Furthermore, in the media supply device 10, the multiple illumination units 24 are positioned offset from the edge of the paper P that is photographed by the camera 18, either approaching or moving away from it. Therefore, the media supply device 10 can detect multiple sheets of paper P photographed by the camera 18 with greater accuracy compared to a case where the multiple illumination units are positioned at the same distance from the edge of the paper that is photographed by the camera.

[0098] Furthermore, in the media supply device 10, the camera 18 is positioned opposite the multiple sheets of paper P that are levitated and separated by the supply unit 14, and the illumination unit 24 is positioned at least above the camera 18 in the vertical direction. That is, the illumination unit 24 is positioned close to the uppermost sheet of paper P that is fed out by the delivery unit 16. Therefore, the media supply device 10 can detect the multiple sheets of paper P captured by the camera 18 with greater accuracy compared to the case where the illumination unit is positioned only below the camera in the vertical direction.

[0099] Furthermore, in the media supply device 10, the multiple illumination units 24 are positioned above and below the camera 18 in the vertical direction. Therefore, the media supply device 10 can detect multiple sheets of paper P captured by the camera 18 with greater accuracy compared to a case where the illumination units are positioned only above the camera in the vertical direction.

[0100] Furthermore, in the media supply device 10, the camera 18 is positioned in the center in the vertical direction, facing the multiple sheets of paper P that are levitated and separated by the supply unit 14. Therefore, in the media supply device 10, the camera can detect the multiple sheets of paper P captured by the camera 18 with greater accuracy compared to the case where the camera is positioned below the multiple media that are levitated and separated by the supply unit.

[0101] Furthermore, in the media supply device 10, the CPU 51 excludes the unidentifiable area 82, which is unsuitable for identifying the paper P, based on the relative position of the position where the light irradiation unit 22 irradiates light in the vertical direction and the paper P, and detects the edge of the paper P in the captured image corresponding only to the identifiable area 80, where the paper P can be identified. As a result, the media supply device 10 can detect multiple sheets of paper P with higher accuracy compared to detecting the edge of the paper from the entire captured image.

[0102] Furthermore, in the media supply device 10, the CPU 51 compares the positions of the edges of the paper P detected for each captured image. If the difference in the positions of the edges of the paper P is less than or equal to a threshold, it is considered the same paper P; if it is greater than the threshold, it is detected as a new paper P. Therefore, in the media supply device 10, Compared to a method that does not determine the identity of the paper detected for each captured image, this method can accurately detect multiple sheets of paper P.

[0103] Furthermore, in the media supply device 10, the CPU 51 creates a filter 90 that is widened by a predetermined width in the thickness direction from the center position of the edge of the paper P detected in the nth captured image. Then, when the center position of the edge of the paper P detected in the (n+1)th captured image falls inside the filter 90, the CPU 51 determines that it is the same paper P and updates the filter 90 with a new filter that is widened by a predetermined width in the thickness direction from the center position of the edge of the paper P in the (n+1)th captured image. As a result, the media supply device 10 can detect multiple paper P with higher accuracy compared to when the same filter is always used.

[0104] Furthermore, the image forming apparatus 100 includes a media supply device 10 and an image forming unit 102 that forms an image on the paper P supplied by the media supply device 10. Therefore, the image forming apparatus 100 can accurately detect multiple sheets of paper P captured by the camera 18 compared to the case where light is shone onto the paper from the same position in the vertical direction.

[0105] 〔supplementary explanation〕 In the media supply device of the first embodiment, the number of illumination units 24 can be changed. Preferably, the illumination units 24 are arranged at least above the camera 18 in the vertical direction. In addition, the position of the illumination units 24 in the depth direction relative to the end of the paper P that is photographed by the camera 18 may be changed.

[0106] Furthermore, in the media supply device of the first embodiment, the vertical positional relationship between the multiple lighting units 24 and the camera 18 may be changed.

[0107] Furthermore, in the media supply device of the first embodiment, the light irradiation unit 22 can be changed to any other configuration as long as it irradiates light onto the end of the paper P on the side to be photographed by the camera 18 from multiple different positions in the vertical direction. For example, the light irradiation unit may have one illumination unit that moves in the vertical direction. Alternatively, one light irradiation unit may be provided, and a mirror that reflects light may be used to change the position of the light in the vertical direction.

[0108] Furthermore, in the media supply device of the first embodiment, the ranges of the discriminable area 80 and the indiscriminate area 82 can be changed depending on the relative position between the lighting position of the lighting unit 24 and the paper P.

[0109] Furthermore, in the media supply device of the first embodiment, the cameras 18 were provided on both sides in the width direction of the paper P, but the present disclosure is not limited to this configuration. For example, the cameras may be provided on either side in the width direction of the paper P.

[0110] The processing performed by the media supply device 10 described above can also be implemented by a dedicated hardware circuit. In this case, it may be performed by one piece of hardware or by multiple pieces of hardware.

[0111] Furthermore, the program for operating the media supply device 10 may be provided on a computer-readable recording medium such as a USB (Universal Serial Bus) memory, a flexible disk, or a CD-ROM (Compact Disc Read Only Memory), or it may be provided online via a network such as the Internet. In this case, the program recorded on the computer-readable recording medium is usually transferred to and stored in memory or storage. This program may also be provided, for example, as a standalone application software, or it may be incorporated into the software of the media supply device 10 or the image forming apparatus 100 as a function of each device.

[0112] Although the present invention has been described in detail with respect to specific embodiments, it will be apparent to those skilled in the art that the present invention is not limited to these embodiments, and that various other embodiments are possible within the scope of the present invention.

[0113] [Note] (((1))) A loading section in which media can be stacked vertically, A supply unit that supplies air to a plurality of media loaded in the loading section to levitate and separate the plurality of media, A transport unit that sequentially delivers the medium that has been lifted and separated by the supply unit, A camera unit that photographs the state in which the medium is being lifted and separated by the supply unit, A light irradiation unit that irradiates light onto the end of the medium on the side where it is photographed by the imaging unit, from multiple different positions in the vertical direction, A medium supply device having

[0114] (((2))) Equipped with at least one processor, The aforementioned processor, The media supply device according to (((1))), wherein if it is determined from the image captured by the imaging unit that there is a concern about clogging or double feeding of the media, the amount of air supplied by the supply unit is changed.

[0115] (((3))) Equipped with at least one processor, The aforementioned processor, A medium supply device according to (((1))) or (((2))), wherein for each image captured by the imaging unit, the vertical position in which the light is irradiated onto the medium by the light irradiation unit is changed to acquire the captured image.

[0116] (((4))) The medium supply device according to any one of (((1))) to (((3))), wherein the light irradiation unit has a plurality of illumination units arranged at different positions in the vertical direction.

[0117] (((5))) The media supply device according to (((4))), wherein the plurality of illumination units are arranged offset in a direction toward or away from the end of the medium that is photographed by the photographing unit.

[0118] (((6))) The imaging unit is positioned opposite the plurality of media that are levitated and separated by the supply unit. The lighting unit is positioned at least above the imaging unit in the vertical direction, as described in (((4))) or (((5))) for the medium supply device.

[0119] (((7))) The media supply device according to (((6))), wherein the plurality of illumination units are arranged on the upper and lower sides in the vertical direction relative to the imaging unit.

[0120] (((8))) The media supply device according to any one of (((1))) to (((7))), wherein the imaging unit is located in the central part in the vertical direction, facing the plurality of media that are levitated and separated by the supply unit.

[0121] (((9))) The aforementioned processor, The medium supply device according to (((3))), wherein the light irradiation unit removes areas unsuitable for identifying the medium from the relative position between the position from which light is irradiated in the vertical direction and the medium, and detects the edges of the medium in the captured image corresponding only to the areas in which the medium can be identified.

[0122] (((10))) The aforementioned processor, A media supply device according to (((3))) or (((9))), which compares the positions of the edges of the media detected for each captured image, and if the difference in the positions of the edges of the media is less than or equal to a threshold, it is detected as the same media, and if it is greater than the threshold, it is detected as a new media.

[0123] (((11))) The aforementioned processor, A filter is created that is thickened by a width in the thickness direction determined from the center position of the edge of the medium detected in the nth captured image, The medium supply device according to (((10))) wherein if the center position of the edge of the medium detected in the (n+1)th captured image falls inside the filter, it is determined to be the same medium, and the filter is updated with a new filter that is thickened by a width in the thickness direction determined from the center position of the edge of the medium in the (n+1)th captured image.

[0124] (((12))) A media supply device described in any one of (((1))) to (((11))), An image forming unit that forms an image on a recording medium supplied by the media supply device, An image forming apparatus having

[0125] According to the media supply device described in (((1))), compared to the case where light is irradiated onto the media from only one identical position in the vertical direction, multiple media captured by the imaging unit can be detected with greater accuracy.

[0126] According to the media supply device described in (((2))), clogging or double feeding of the media can be suppressed compared to the case where the amount of air supplied is always constant.

[0127] According to the media supply device described in (((3))), compared to the case where light is shone onto the medium from the same position in the vertical direction to acquire multiple captured images, multiple media captured by the imaging unit can be detected with greater accuracy.

[0128] The media supply device described in (((4))) has a simpler structure compared to the case in which light is irradiated onto the media from different positions in the vertical direction using a single light irradiation unit.

[0129] According to the media supply device described in (((5))), compared to the case where multiple irradiation units are arranged at the same distance from the end of the media that is photographed by the imaging unit, multiple media photographed by the imaging unit can be detected with greater accuracy.

[0130] According to the media supply device described in (((6))), multiple media captured by the imaging unit can be detected with greater accuracy compared to the case where the illumination unit is located only on the lower side in the vertical direction relative to the imaging unit.

[0131] According to the media supply device described in (((7))), compared to the case where the illumination unit is located only above the imaging unit in the vertical direction, multiple media captured by the imaging unit can be detected with greater accuracy.

[0132] According to the media supply device described in ((8)), the imaging unit can detect multiple media captured by the imaging unit with greater accuracy compared to the case where the imaging unit is positioned below the multiple media that are levitated and separated by the supply unit.

[0133] According to the media supply device described in (((9))), multiple media can be detected with greater accuracy compared to detecting the edges of the media from the entire captured image.

[0134] According to the media supply device described in (((10))), multiple media can be detected with greater accuracy compared to cases where the identity of the media detected for each captured image is not determined.

[0135] According to the media supply device described in (((11))), multiple media can be detected with greater accuracy compared to the case where the same filter is always used.

[0136] According to the image forming apparatus described in (((12))), compared to the case where light is shone onto the medium from the same position in the vertical direction, multiple media captured by the imaging unit can be detected with high accuracy. [Explanation of Symbols]

[0137] 10 Media supply device 12 Loading section 14 Supply section 16. Dispensing section (an example of a transport section) 18. Camera (an example of a camera unit) 22 Light-irradiating section 24 Multiple lighting units 24A 1st lighting section 24B 2nd lighting section 24C 3rd lighting section 24D 4th lighting section 50 Control device 51 CPU (an example of a processor) 52 ROM 53 RAM 54 storage 55 Input / Output Interfaces 59 bus 71 Light Irradiation Control Unit 72 Image acquisition unit 73 Paper Calculation Unit 74 Paper condition determination unit 75 Air supply volume change unit 80. Discriminationable area (an example of an area unsuitable for media identification) 82. Unidentifiable Area (An example of an area where the medium can be identified) 90 filters 100 Image forming apparatus 102 Image forming unit P paper (an example of a medium)

Claims

1. A loading section in which media can be stacked vertically, A supply unit that supplies air to a plurality of media loaded in the loading section to levitate and separate the plurality of media, A transport unit that sequentially delivers the medium that has been lifted and separated by the supply unit, A camera unit that photographs the state in which the medium is being lifted and separated by the supply unit, A light irradiation unit that irradiates light onto the end of the medium on the side where it is photographed by the imaging unit, from multiple different positions in the vertical direction, At least one processor, It has, The aforementioned processor, For each image captured by the imaging unit, the vertical position of the light irradiation unit irradiating the medium with light is changed to acquire the image. A media supply device that compares the positions of the edges of the media detected for each captured image, and detects them as the same media if the difference in the positions of the edges of the media is less than or equal to a threshold, and as a new media if it is greater than the threshold.

2. The processor is The medium supply device according to claim 1, wherein if it is determined that there is a concern that clogging or double feeding of the medium may occur depending on the buoyancy and separation state of the medium in the image captured by the imaging unit, the amount of air supplied by the supply unit is changed.

3. The medium supply device according to claim 1, wherein the light irradiation unit has a plurality of illumination units arranged at different positions in the vertical direction.

4. The medium supply device according to claim 3, wherein the plurality of illumination units are arranged offset in a direction toward or away from the end of the medium that is photographed by the photographing unit.

5. The imaging unit is positioned opposite to the plurality of media that are lifted and separated by the supply unit, The medium supply device according to claim 3, wherein the illumination unit is positioned at least above the imaging unit in the vertical direction.

6. The media supply device according to claim 5, wherein the plurality of illumination units are arranged above and below the imaging unit in the vertical direction.

7. The media supply device according to claim 5, wherein the imaging unit is located in the central part in the vertical direction, facing the plurality of media that are levitated and separated by the supply unit.

8. The processor is The medium supply device according to claim 1, wherein the light irradiation unit removes areas unsuitable for identifying the medium from the relative position between the position from which light is irradiated in the vertical direction and the medium, and detects the edges of the medium in the captured image corresponding only to the areas in which the medium can be identified.

9. The processor is A filter is created that is thickened by a width in the thickness direction determined from the center position of the edge of the medium detected in the nth captured image, When the center position of the edge of the medium detected in the (n+1)th captured image falls inside the filter, it is determined to be the same medium, and the center of the edge of the medium in the (n+1)th captured image The media supply device according to claim 1, which replaces the filter with a new filter that has been widened by a width in the thickness direction determined from the position.

10. The processor is The media supply device according to claim 2, which detects the floating and separation state of the ends of the media, and determines that there is a concern that the media may become clogged or double-feeded if the number of media less than or equal to a first threshold is floating, or if the number of media more than or equal to a second threshold is in a bundled state that is not separated.

11. A media supply device according to any one of claims 1 to 10, An image forming unit that forms an image on the medium supplied by the medium supply device, An image forming apparatus having

Images