Medium supply device

Abstract

To suppress waving of a medium in a medium supplying device which separates the medium by blowing air onto an upstream portion in a supply direction of the medium.SOLUTION: A medium supply device 1 includes: a loading table 10 on which a medium M is loaded; a blower 20 which blows air A toward an upstream portion Ma of the medium M on the loading table 10 in a supply direction F to separate a plurality of media M from each other; and at least one pair of resistance portions (for example, two pairs of resistance portions 31, 32) whose spacing in a width direction W of the medium M perpendicular to the supply direction F gradually increases from an upstream side to a downstream side of the supply direction F and which contact a top surface of an uppermost medium M on the loading table 10.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a media supply device. [Background technology]

[0002] BACKGROUND ART Conventionally, there is known a sheet conveying device having a pressing member of a skew prevention mechanism that contacts the widthwise edge of the uppermost surface of a sheet to press the sheet (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-345797 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, in a media supply device installed in an image forming apparatus or the like, in order to supply media that are difficult to separate due to friction or static electricity between media such as paper (for example, carbonless paper) or media with low stiffness such as thin paper, a configuration is known in which air is sent in from the rear end of the media stack (air assist) to separate the media and assist supply while the media is transported by a supply roller.

[0005] In such a medium supplying device, a presser member is generally used to press down the topmost medium from above to prevent the medium, which has been floated by air assist, from floating too high and breaking apart.

[0006] However, because air is blown into the floating topmost medium even when it is held down by the presser member, the weaker the medium, the more likely it is to ripple, and the trailing edge of the medium (the upstream side in the supply direction) ripples as it moves along while being transported by the supply roller. This causes the ripples at the trailing edge of the medium to be crushed by the supply roller and the transport rollers beyond, resulting in problems such as wrinkles and jams in the medium.

[0007] Increasing the rigidity of the presser member to prevent waving of the media makes it impossible to separate the media in the first place. Furthermore, a presser member that partially contacts the top surface of the uppermost media, such as the presser member of the skew prevention mechanism described above, can crush the waving at the rear end of the media, causing wrinkles in the media.

[0008] An object of the present invention is to suppress waviness of media in a media supplying device that separates media by blowing air onto an upstream portion of the media in the supply direction. [Means for solving the problem]

[0009] In one embodiment, the medium supply device includes a loading platform on which media is loaded, a blower that blows air toward the upstream portion of the loading platform in the supply direction of the media to separate the media from each other, and at least one pair of resistance portions that gradually increase the spacing between the media in the width direction of the media perpendicular to the supply direction from the upstream side to the downstream side in the supply direction and that contact the top surface of the uppermost media on the loading platform. [Effects of the Invention]

[0010] According to the above aspect, in a medium supplying device that separates media by blowing air onto an upstream portion in the supply direction of the media, waving of the media is suppressed. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a front view showing an internal structure of a medium supply device according to an embodiment. [Figure 2]FIG. 1 is a plan view illustrating a medium supply device according to an embodiment. [Figure 3] FIG. 2 is a block diagram showing a control configuration of a medium supply device according to an embodiment. [Figure 4] FIG. 10 is a plan view illustrating a function of a resistor portion according to an embodiment. [Figure 5A] FIG. 10 is a plan view illustrating a resistor portion according to a first modified example of the embodiment. [Figure 5B] FIG. 10 is a plan view illustrating a resistor portion according to a second modified example of the embodiment. [Figure 5C] FIG. 10 is a plan view illustrating a resistance portion according to a third modified example of the embodiment. [Figure 5D] FIG. 10 is a cross-sectional view illustrating a resistor portion according to a fourth modified example of the embodiment. [Figure 6] FIG. 10 is a perspective view illustrating waviness of a medium. [Figure 7] 10 is a plan view showing each supply roller and the like of a medium supply device according to another embodiment. FIG. [Figure 8] FIG. 10 is a left side view showing a central supply roller according to another embodiment. [Figure 9] 10A and 10B are perspective views showing supply rollers according to another embodiment. [Figure 10] FIG. 10 is a perspective view showing each supply roller in a first modified example of another embodiment. [Figure 11] FIG. 10 is a perspective view showing each supply roller in a second modified example of the other embodiment. [Figure 12] FIG. [Figure 13] FIG. 1 is a perspective view showing a curled medium. [Figure 14] FIG. 10 is a perspective view illustrating a portion that may cause double feeding. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, a medium supplying device according to one embodiment and another embodiment of the present invention will be described with reference to the drawings.

[0013] <One embodiment> 1 to 3 are a front view and a plan view showing the internal structure of a medium supplying device 1 according to the present embodiment, and a block diagram showing a control configuration.

[0014] 1 and 2, 4, 5A to 5D, and 6 described later, and 7 to 11 and 14 in other embodiments, the front-rear, up-down, and left-right directions are horizontal directions, and the up-down directions are vertical directions, which are perpendicular to each other. These directions are an example when the supply direction F of the medium M is set to the left.

[0015] As shown in FIG. 1, the medium supplying device 1 includes a loading platform 10, a blower 20, two pairs of resistance units 31 and 32, a pressure sheet 40, a supply roller 50, and a tray 60. As shown in FIG. 2, the medium supplying device 1 includes a sheet support unit 70, a pair of side fences 81, and an end fence 82. As shown in FIG. 3, the medium supplying device 1 includes a control unit 91, a memory unit 92, an interface unit 93, an elevation drive unit 94, and a roller drive unit 95. Note that the sheet support unit 70, the pair of side fences 81, the end fence 82, the control unit 91, etc. are not shown in FIG. 1, and the tray 60, the control unit 91, etc. are not shown in FIG. 2.

[0016] The medium M is, for example, paper. The medium supply device 1 can be used as an internal paper supply device housed inside the image forming device. However, the medium supply device 1 may also be used as an external paper supply device exposed to the outside of the image forming device, or may be used to supply the medium M to a device other than the image forming device.

[0017] As shown in Fig. 1, media M (a stack of media) is loaded on loading platform 10. Loading platform 10 has, for example, a flat plate shape, and is rotatably supported by tray 60 at a pair of rotational center shafts 11 provided at the upstream end in the supply direction F of media M. Loading platform 10 moves up and down by rotating (tilting) around rotational center shafts 11 as the center of rotation, but it may also move up and down in a horizontal position.

[0018] 2, the loading platform 10 is provided with a pair of long holes 12 extending in the supply direction F and penetrating a pair of side fences 81 in the vertical direction. In addition, the loading platform 10 is bifurcated at only both ends of the width direction W of the medium M on the upstream side of the supply direction F to avoid interference with an end fence 82 (shown by a hidden dashed line in FIG. 2) and the like.

[0019] The blower 20 has an airflow generating means such as a fan and blows air A toward an upstream portion Ma of the media M on the loading platform 10 in the supply direction F, separating the media M from one another. The blower 20 preferably constantly blows air A while the media M is being continuously supplied. The blower 20 is disposed upstream of the media M loaded on the loading platform 10 in the supply direction F, and blows air A in the supply direction F toward the upper media M on the loading platform 10. However, the blower 20 may also be disposed upstream of the media M in the supply direction F and on one or both sides of the media M in the width direction W, and blow air A diagonally intersecting the supply direction F and the width direction W to blow air A toward the upstream portion Ma of the media M. The blowing of air A by the blower 20 is referred to as an air assist, and the blower 20 may also be referred to as an air assist device.

[0020] As shown in FIG. 2 , a pair of resistance portions 31 and a pair of resistance portions 32 are provided on the bottom surface 41 of the pressure sheet 40, for example, by adhesive, and contact the top surface of the uppermost medium M loaded on the stacking table 10. In FIG. 2 , the resistance portions 31 and 32 are hidden by the pressure sheet 40 and are therefore illustrated by hidden dashed lines. For example, the resistance portions 31 and 32 may be sponge-like or plastic parts and have a three-dimensional shape, such as a rectangular parallelepiped. Upon contact with the medium M, the resistance portions 31 and 32 exert a kinetic frictional force that does not impede the supply of the medium M, thereby suppressing undulation of the medium M, as described below. Note that the resistance portions 31 and 32 may have a planar shape rather than a three-dimensional shape, and may be, for example, a processed portion formed on the bottom surface 41 of the pressure sheet 40. It is preferable that this processed portion exerts a stronger kinetic frictional force with the medium M than other portions of the bottom surface 41 of the pressure sheet 40. Furthermore, the resistance portions 31 and 32 may not be provided on the bottom surface 41 of the pressing sheet 40, but may be held by a member (such as an arm) different from the pressing sheet 40.

[0021] The pair of resistance portions 31 are located downstream of the pair of resistance portions 32 in the supply direction F. One of the pair of resistance portions 31 and the pair of resistance portions 32 is located on one side (front side) of the center of the medium M in the width direction W of the medium M, which is perpendicular to the supply direction F, and the other of the pair of resistance portions 31 and 32 is located on the opposite side (rear side) of the center of the medium M in the width direction W. The pair of resistance portions 31 and the pair of resistance portions 32 extend obliquely from the upstream side to the downstream side in the supply direction F, moving away from the center of the medium M in the width direction W. As a result, as shown in FIG. 4, the pair of resistance portions 31 and the pair of resistance portions 32 are arranged, for example, in a figure-eight shape (a V shape separated in the width direction W) so that the distance between them in the width direction W gradually increases (length L1 → L2) from the upstream side (length L1) to the downstream side (length L2) in the supply direction F. At least one of the pair of resistance portions 31 and the pair of resistance portions 32 may be composed of one resistance portion 31, 32 extending parallel to the supply direction F and the other resistance portion 31, 32 extending obliquely from the one resistance portion 31, 32 to the downstream side in the supply direction F so as to move away from the one resistance portion 31, 32 in the width direction W. The resistance portions 31, 32 may also be called convex portions, protrusions, protruding portions, protruding members, protruding portions, protruding members, etc.

[0022] The holding sheet 40 is disposed above the uppermost medium M on the stacking table 10 and holds down the uppermost medium M from above to prevent the medium M (particularly the upstream portion Ma) from being excessively lifted by the blowing of air A by the blower 20. As described above, two pairs of resistance portions 31, 32 are provided on the bottom surface 41 of the holding sheet 40. A notch 42 is provided in the center of the width direction W of the downstream end of the holding sheet 40 in the supply direction F to avoid interference with the supply roller 50. The holding sheet 40 may be disposed, for example, over an area that is at least half of the supply direction F of the medium M and at least half of the width direction W of the medium M. The holding sheet 40 is made of, for example, plastic and has the property (flexibility) of being deformed by the tilt of the stacking table 10 (the uppermost medium M) and the blowing of air A by the blower 20. The holding sheet 40 has a higher rigidity than the medium M when the two pairs of resistance portions 31, 32 are provided, and at least a portion (at least the upstream end in the supply direction F) of the holding sheet 40 is lifted by the blowing of air A by the blower 20. As shown in FIG. 2, the holding sheet 40 is preferably supported by a sheet support portion 70 (described later) at a pair of connecting portions 43 arranged in the width direction W at the top of the holding sheet 40.

[0023] The supply roller 50 is positioned above the downstream end of the media M in the supply direction F. When the lifting / lowering drive unit 94 (described later) tilts the stacking table 10, the supply roller 50 is pressed upward by the downstream end of the uppermost medium M in the supply direction F. The supply roller 50 then pays out the uppermost medium M in the supply direction F. The supply roller 50 is an example of a supply member (feeder) that supplies media M from the medium supplying device 1 to another device. This supply member may be a belt or a suction belt with suction holes. Note that the medium supplying device 1 is provided with a sensor that detects the supply roller 50 being pressed upward by the downstream end of the uppermost medium M in the supply direction F. When the sensor detects that the upward pressure of the supply roller 50 has decreased (for example, when several sheets of media M are supplied), the control unit 91 (described later) controls the lifting / lowering drive unit 94 to tilt the stacking table 10 so that the angle of inclination of the stacking table 10 with respect to the horizontal increases.

[0024] 1 has a rectangular shape that opens upward and accommodates the loading platform 10, the blower 20, etc. The tray 60 is disposed particularly when the medium supplying device 1 is used as an internal paper feeding device of the image forming device as described above, but may be omitted regardless of the use of the medium supplying device 1. Furthermore, when the airflow generating means of the blower 20 is disposed outside the tray 60, the tray 60 accommodates a duct portion of the blower 20 or is provided with an outlet for the blower 20.

[0025] The sheet support part 70 shown in Fig. 2 has an arm 71 and a pair of arm holding parts 72 that hold the arm 71. The arm 71 is held at both ends by the pair of arm holding parts 72 and is rotatable (swingable) around the both ends extending in the width direction W, which are the held parts. The arm 71 has a U-shape that opens on the upstream side in the supply direction F in a plan view (see Fig. 2), and is rotatably (swingably) connected to a pair of connecting parts 43 of the presser sheet 40 at its downstream end in the supply direction F. In this way, the sheet support part 70 supports the presser sheet 40 so that it can be lifted by the blowing of air A by the blower 20.

[0026] The pair of side fences 81 regulates the position in the width direction W of the media M loaded on the loading platform 10. As described above, the pair of side fences 81 pass through the holes 12 of the loading platform 10 in the vertical direction.

[0027] The end fence 82 regulates the position of the upstream end of the medium M loaded on the loading platform 10 in the supply direction F. The end fence 82 preferably has a narrow dimension in the width direction W or a large hollow portion so as not to interfere with the blowing of air A by the blower 20 toward the upstream portion Ma of the medium M. The end fences 82 may also be disposed on both end portions of the medium M in the width direction W so as not to interfere with the blowing of air A by the blower 20 toward the upstream portion Ma of the medium M. Note that, because the plurality of media M loaded on the loading platform 10 can be considered to be sandwiched between the supply roller 50 and the loading platform 10, the end fences 82 may be omitted.

[0028] The control unit 91 shown in FIG. 3 has, for example, one or more processors (e.g., CPU: Central Processing Unit) that function as an arithmetic processing device that controls the operation of each part of the medium supplying device 1. This processor reads and executes a predetermined program, for example, from the memory unit 92 or from a storage medium (non-transitory computer-readable recording medium) that is detachable from the medium supplying device 1. In this way, the control unit 91 functions as an example of a computer that executes a program. The control unit 91 may adjust the air volume of the blower 20 based on the type of medium M, such as thickness, basis weight, or size. Note that when the medium supplying device 1 is disposed as part of another device, such as an image forming device, the control unit and memory unit of the other device may also serve as the control unit 91 and memory unit 92 of the medium supplying device 1.

[0029] The storage unit 92 includes, for example, a memory such as a ROM (Read Only Memory), which is a read-only semiconductor memory in which a predetermined control program is pre-recorded, a RAM (Random Access Memory), which is a semiconductor memory that can be written and read at any time and is used as a working memory area as needed when the processor executes various control programs, or a hard disk device.

[0030] The interface unit 93 exchanges various information with external devices such as an image forming apparatus.

[0031] The lifting / lowering drive unit 94 is an actuator such as a motor that tilts and raises the loading platform 10 around the rotation center shaft 11. A mechanism including the lifting / lowering drive unit 94 and the loading platform 10 can be called an elevator mechanism.

[0032] The roller driving unit 95 is an actuator such as a motor for driving the supply roller 50 .

[0033] 6, the upper multiple sheets of media M, including the topmost medium M on the stacking table 10, are separated from one another by the upstream portion Ma being lifted by the blowing of air A by the blower 20. However, when air A is blown between the multiple sheets of media M, the media M are prone to waving at the upstream portion Ma. This waving is more likely to occur the weaker the media M is.

[0034] In this regard, in the present embodiment, as described above, the distance between each pair of resistance portions 31 and each pair of resistance portions 32 in the width direction W gradually increases from the upstream side (length L1) to the downstream side (length L2) in the supply direction F, as shown in FIG. 4 . Therefore, as the medium M is supplied by the supply roller 50, the back tension of the two pairs of resistance portions 31 and 32 causes the waviness caused by the blowing of air A to spread in the width direction W. This causes the medium M to flatten, thereby eliminating the waviness. Furthermore, because a space corresponding to the height of the resistance portions 31 and 32 is provided between the top surface of the uppermost medium M and the bottom surface 41 of the pressure sheet 40, the air A flows (rectifies) in a direction that spreads the medium M in the width direction W along the shape of the resistance portions 31 and 32, as shown by the thick arrows in FIG. 4 , and this also eliminates the waviness. This prevents wrinkles and jams from occurring due to the supply roller 50 or a transport roller disposed downstream of the supply roller 50 in the supply direction F stamping out the waviness of the medium M. In Fig. 4, to represent the waviness of the medium M (three thin solid lines), the resistance portions 31 and 32 and the pressing sheet 40 are shown with imaginary two-dot chain lines.

[0035] Next, first to fourth modified examples of this embodiment will be described with reference to FIGS. 5A to 5D.

[0036] In the first modified example shown in Fig. 5A, the pressing sheet 40 is provided with only a pair of resistor portions 131. In this manner, only a pair of resistor portions 131 may be arranged. Note that the pair of resistor portions 131 are arranged in the same positions as the resistor portions 32 shown in Fig. 2, for example, but they may be arranged at any positions with any interval between them.

[0037] In a second modified example shown in FIG. 5B, the pressing sheet 40 has three pairs of resistance portions 231, 232, and 233 arranged side by side in the supply direction F. Two of the three pairs of resistance portions 231 and 232 are arranged in the same positions as the resistance portions 31 and 32 shown in FIG. 2, for example. The resistance portion 233 is arranged upstream of the resistance portion 232 in the supply direction F. In this way, three or more pairs of resistance portions 231 to 233 may be arranged. The number of resistance portions 231 to 233 may be determined depending on the strength and position of the waviness.

[0038] In a third modified example shown in FIG. 5C, five pairs of resistor portions 331, 332, 333, 334, and 335 are provided on the presser sheet 40 in a staggered pattern in the supply direction F. Three of the five pairs of resistor portions 331, 333, and 335 are similarly arranged in the same positions as the resistor portions 231 to 233 shown in FIG. 5B, for example. The resistor portions 332 and 334 are arranged closer to the center in the width direction W of the medium M than the resistor portions 331, 333, and 335, and are spaced closer to each other. In this way, the resistor portions 332 and 334 and the resistor portions 331, 333, and 335 are located at different positions in the width direction W. The positions, spacing, and number of the resistor portions 331 to 335 may be determined depending on the strength and position of the waviness.

[0039] 5D, a pair of resistors 441 (only one of which is shown) are integrally formed on the pressing sheet 440. The pair of resistors 441 are beaded portions that can be formed by pressing or molding, for example. As described above, the resistors 441 integrally formed on the pressing sheet 440 may be any number of pairs (one or more), at any positions, or in any number, or may be arranged in a staggered pattern.

[0040] In the present embodiment described above, the medium supply device 1 includes a loading table 10, a blower 20, and at least one pair of resistance portions 31 and 32. Media M are loaded on the loading table 10. The blower 20 blows air A toward an upstream portion Ma of the media M on the loading table 10 in the supply direction F, separating the multiple media M from one another. The distance between the resistance portions 31 and 32 in the width direction W of the media M perpendicular to the supply direction F gradually increases from the upstream side to the downstream side in the supply direction F (length L1 → L2), and the resistance portions 31 and 32 come into contact with the top surface of the uppermost medium M on the loading table 10.

[0041] Because the distance between the resistance portions 31 and 32 in the width direction W gradually increases from the upstream side to the downstream side in the supply direction F (length L1 → L2), the back tension of the resistance portions 31 and 32 when the medium M is supplied spreads the waving of the medium M caused by the blowing of air A in the width direction W, eliminating the waving. Furthermore, because a space corresponding to the height of the resistance portions 31 and 32 is provided between the uppermost medium M and the bottom surface 41 of the pressure sheet 40, the air A flows along the resistance portions 31 and 32 in a direction that spreads the medium M in the width direction W (rectification), thereby eliminating the waving. Therefore, according to this embodiment, the medium supply device 1, which separates the medium M by blowing air A against the upstream portion Ma of the medium M in the supply direction F, can suppress waving of the medium M. This prevents the supply roller 50 and a transport roller (not shown) located downstream of the supply roller 50 in the supply direction F from stamping out the waving of the medium M, thereby preventing wrinkles and jams from occurring.

[0042] In this embodiment, the medium supplying device 1 further includes a pressing sheet 40 having at least one pair of resistance portions 31, 32 provided on the bottom surface 41, and pressing down the uppermost medium M from above.

[0043] This makes it possible to prevent the medium M from floating too high and becoming uneven by using the pressure sheet 40. Furthermore, compared to an embodiment in which the resistance portions 31, 32 of the medium M are arranged independently of the pressure sheet 40, the resistance portions 31, 32 can be arranged with a simpler configuration.

[0044] In the present embodiment, the pressing sheet 40 has higher rigidity than the medium M when the resistance portions 31 and 32 are provided, and at least a portion of the pressing sheet 40 is lifted up by the blowing of the air A by the blower 20.

[0045] As a result, the presser sheet 40 is used to prevent the media M from floating too high and becoming scattered, while the air A is blown between the plurality of media M, allowing the media M to be separated.

[0046] In the fourth modification of this embodiment, the resistance portion 441 is provided integrally with the pressing sheet 440.

[0047] This makes it possible to reduce the number of parts (cost) and assembly steps, as well as to prevent the resistance portion 441 from falling off, compared to a configuration in which the resistance portion 441 is provided as a separate member from the pressing sheet 440.

[0048] In this embodiment, the medium supply device 1 includes a plurality of pairs of resistance portions 31 and 32.

[0049] As a result, each pair of resistance portions 31, 32 can eliminate waving of the medium M caused by the blowing of the air A, and therefore, waving of the medium M can be further suppressed.

[0050] <Other embodiments> The medium supply device 2 according to this embodiment differs from the medium supply device 1 according to the above-described embodiment mainly in that three supply rollers 551 to 553 are provided instead of the supply roller 50, but other features can be the same. Therefore, in this embodiment, only the features that differ from the above-described embodiment will be described.

[0051] Fig. 7 is a plan view showing the supply rollers 551 to 553 etc. In Fig. 7, the resistance portions 531 to 535 and the pressing sheet 550 are shown by two-dot chain lines which are imaginary lines.

[0052] First, the five pairs (one example of at least one pair) of resistance portions 531-535 are arranged so that the distance between them in the width direction W of the medium M perpendicular to the supply direction F gradually increases from the upstream side to the downstream side in the supply direction F, and they are arranged so as to contact the upper surface of the uppermost medium M on the stacking table 10 (see FIGS. 1 and 2). As described in the above embodiment, the resistance portions 531-535 can be arranged at any intervals, positions, and number, and may be fixed to the bottom surface of the pressure sheet 540 or formed integrally with the pressure sheet 540, for example.

[0053] The resistance portions 531 to 535 are located at different positions in the supply direction F and the width direction W. It is preferable that any one of the resistance portions 531 to 535 is located at the same position in the width direction W as between the central supply roller 551 and the first side supply roller 552 and between the central supply roller 551 and the second side supply roller 553.

[0054] 2, the pressing sheet 540 is disposed upstream of the supply rollers 551 to 553 in the supply direction F, and therefore does not have the notches 42 for avoiding interference with the supply rollers 551 to 553. However, the pressing sheet 540 may have the notches 42 for avoiding interference with the supply rollers 551 to 553.

[0055] Incidentally, even if the medium M is cut paper, the curling tendency differs depending on whether the position cut from the roll paper R (raw sheet) is on the core Ra or on the outside Rb of the roll, as shown in Figure 12. This tendency also differs depending on the roll direction, the front / back orientation of the medium M, the material, thickness, etc.

[0056] For example, as shown in Fig. 13, when the medium M floats, the downstream end in the supply direction F may curl and sag downward at both ends in the width direction W. In this case, when air A is blown out by the blower 20 shown in Fig. 14, it becomes difficult to create space between the uppermost medium M and the second medium M at the downstream front portion Mc and downstream rear portion Md (the shaded area surrounded by the dashed line), resulting in poor separation. Therefore, the downstream front portion Mc and downstream rear portion Md become factors that cause double feeding.

[0057] Furthermore, when medium M is fed by the supply roller 50, which is positioned at the center in the width direction W, the supply roller 50 nips the uppermost medium M at a downstream center portion Mb (the shaded portion surrounded by a dashed line) of the uppermost medium M. This prevents air A from flowing downstream in the supply direction F of the supply roller 50, making it difficult for a space to form between the uppermost medium M and the second medium M, resulting in poor separation. Therefore, the downstream center portion Mb also becomes a factor in double feeding.

[0058] Furthermore, in particular, medium M, such as copy paper, which is thin and has high friction, is prone to waving at the downstream end in the supply direction F, as shown in Figure 14. Therefore, as described above, the waving of medium M is crushed by supply roller 50 and the transport rollers beyond it, which can cause medium M to wrinkle or jam.

[0059] Therefore, as shown in Fig. 8, central supply roller 551 in this embodiment has multiple air guide grooves 551a and multiple wrinkle prevention grooves 551b. As will be described later, first side supply roller 552 and second side supply roller 553 also have multiple air guide grooves 552a, 553a and multiple wrinkle prevention grooves 552b, 553b, as shown in Fig. 9. Note that Figs. 9 to 11 only show supply rollers 551 to 553 and medium M.

[0060] The central supply roller 551, first side supply roller 552, and second side supply roller 553 are located above the downstream end of the medium M in the supply direction F, and feed out the uppermost medium M in the supply direction F. The central supply roller 551 is located at the center of the medium M in the width direction W. The first side supply roller 552 is located on one side in the width direction W (front side) of the center of the medium M in the width direction W (central supply roller 551). The second side supply roller 553 is located on the other side in the width direction W (rear side) of the center of the medium M in the width direction W (central supply roller 551).

[0061] As shown in FIG. 8, five air guide grooves 551a of the central supply roller 551 are arranged at intervals in the center of the central supply roller 551 in the width direction W. These air guide grooves 551a extend in the rotation direction D on the outer circumferential surface of the central supply roller 551. By providing the air guide grooves 551a in the central supply roller 551 in this manner, the central supply roller 551 does not nip the uppermost medium M in the area where the air guide grooves 551a are provided. Therefore, as shown in FIG. 9, air A flows (rectified) between the uppermost medium M and the second medium M located below it in the area where the air guide grooves 551a are provided. Note that in FIG. 9, the air A blown out from the blower 20 mainly flows between the media M (for example, between the uppermost medium M and the second medium M), and therefore the portion of the air A that flows out to the outside of the media M is illustrated by a hidden dashed line.

[0062] The wrinkle prevention grooves 551b of the central supply roller 551 are provided on both ends of the central supply roller 551 in the width direction W (areas where the multiple air guide grooves 551a are not provided). The wrinkle prevention grooves 551b extend on the outer peripheral surface from the center of the medium M in the width direction W toward the end toward the upstream side in the rotation direction D. The wrinkle prevention grooves 551b extend at an angle, but may also extend in a curved manner. By providing the wrinkle prevention grooves 551b in this manner, the area of ​​the central supply roller 551 where the wrinkle prevention grooves 551b are not provided (the area that nips the uppermost medium M) shifts outward in the width direction W toward the upstream side in the rotation direction D. This causes the medium M to spread outward in the width direction W, eliminating waving of the medium M and suppressing the occurrence of wrinkles.

[0063] As shown in Figure 9, the first side supply roller 552 and the second side supply roller 553, like the central supply roller 551, have air guide grooves 552a and 553a at the center of the medium M in the width direction W, and wrinkle prevention grooves 552b and 553b at the end sides of the medium M in the width direction W.

[0064] 10 , the rotation axes 552c, 553c (shown by dashed lines) of the first side supply roller 552 and the second side supply roller 553 are inclined with respect to the width direction W so that the closer they are to the end of the medium M in the width direction W, the more upstream in the supply direction F they are, unlike the rotation axis 551c (shown by dashed line) of the central supply roller 551, which extends parallel to the width direction W. In this way, by inclining the first side supply roller 552 and the second side supply roller 553, it becomes easier to use the air guide grooves 552a, 553a to direct air A outward in the width direction W, and to use the wrinkle prevention grooves 552b, 553b to spread the medium M in the width direction W and eliminate waviness of the medium M.

[0065] In the second modified example shown in FIG. 11, the first side supply roller 552 and the second side supply roller 553 are inclined as in the first modified example shown in FIG. 10, and two joints 554, 554 are provided. One of the joints, 554, connects the rotation shaft 551c of the central supply roller 551 and the rotation shaft 552c of the first side supply roller 552. The joint 554 is, for example, a universal joint, and is capable of adjusting the angle of the rotation shaft 552c relative to the rotation shaft 551c of the central supply roller 551 in the supply direction F (within a horizontal plane). This angle adjustment may be performed by the control unit 91 described above based on medium information such as the material and thickness of the medium M corresponding to the curl tendency or on a user operation, or may be performed manually by the user.

[0066] The other joint 555 connects the rotation shaft 551c of the central supply roller 551 and the rotation shaft 553c of the second side supply roller 553. Like the joint 554, the joint 555 is, for example, a universal joint, and is capable of adjusting the angle of the rotation shaft 553c relative to the rotation shaft 551c of the central supply roller 551 in the supply direction F (in the horizontal plane).

[0067] The joints 554 and 555 may connect the rotation shafts 552c and 553c of the first and second side supply rollers 552 and 553 to the rotation shaft 551c of the central supply roller 551 so as to be slidable in the axial direction toward and away from each other.

[0068] In the above description, central supply roller 551, first side supply roller 552, and second side supply roller 553 each have both air guide grooves 551a, 552a, 553a and wrinkle prevention grooves 551b, 552b, 553b, but they may each have only one of them. Furthermore, the number of supply rollers 551 to 553 can be any number, and for example, first side supply roller 552 and second side supply roller 553 may be omitted.

[0069] In the above description, the joints 554 and 555 connect the rotation shaft 551c of the central supply roller 551 to the rotation shafts 552c and 553c of the first and second side supply rollers 552 and 553. However, the rotation shafts 552c and 553c of the first and second side supply rollers 552 and 553 may be disposed separately from the rotation shaft 551c of the central supply roller 551. Even in this case, it is possible to adjust the angle of the orientations of the rotation shafts 552c and 553c of the first and second side supply rollers 552 and 553 and to slide them. Furthermore, even if the rotation shafts 552c and 553c of the first and second side supply rollers 552 and 553 are inclined with respect to the width direction W as shown in FIG. 10, the angle of the rotation shafts 552c and 553c of the first and second side supply rollers 553 may not be adjustable.

[0070] In the other embodiments described above, the same effects as those of the above-mentioned embodiment can be obtained, namely, in a medium supply device 2 that separates the medium M by blowing air A onto the upstream portion Ma in the supply direction F of the medium M, the effect of being able to suppress waviness of the medium M can be obtained.

[0071] In addition, in this embodiment, the central supply roller 551, the first side supply roller 552, and the second side supply roller 553, which are examples of supply rollers that feed the top medium M in the supply direction F, have air guide grooves 551a, 552a, and 553a extending in the rotation direction D.

[0072] As a result, each of the supply rollers 551-553 does not nip the uppermost medium M in the area where the air guide grooves 551a, 552a, and 553a are provided. Therefore, below the area where the air guide grooves 551a, 552a, and 553a are provided, air A flows between the uppermost medium M and the second medium M positioned below it. Therefore, air A flows downstream in the supply direction F of each of the supply rollers 551-553, improving separation performance. This makes it possible to prevent double feeding of media M.

[0073] In addition, in this embodiment, the central supply roller 551, the first side supply roller 552, and the second side supply roller 553, which are examples of supply rollers that feed the topmost medium M in the supply direction F, have wrinkle prevention grooves 551b, 552b, and 553b that extend upstream in the rotation direction D from the center side of the medium M in the width direction W of the medium M toward the end side.

[0074] As a result, the area of ​​each supply roller 551-553 where wrinkle prevention grooves 551b, 552b, 553b are not provided (the area that nips the uppermost medium M) shifts outward in the width direction W toward the upstream side of the rotation direction D. Therefore, the medium M spreads outward in the width direction W, which further suppresses rippling of the medium M and more reliably prevents wrinkles. Furthermore, by providing both the air guide grooves 551a, 552a, 553a and the wrinkle prevention grooves 551b, 552b, 553b in each supply roller 551-553, it is possible to prevent double feeding of the medium M and the occurrence of wrinkles in the area where a single supply roller 551-553 is arranged.

[0075] In this embodiment, the first side supply roller 552 is disposed on one side of the center of the medium M in the width direction W, and the second side supply roller 553 is disposed on the other side of the center of the medium M in the width direction W. The first side supply roller 552 and the second side supply roller 553 are capable of adjusting the angle of the rotation axes 552c and 553c in the supply direction F.

[0076] This makes it possible to change the orientation of the air guide grooves 552a, 553a and the wrinkle prevention grooves 552b, 553b according to the curling tendency of the medium M, which differs depending on the position where the medium M was cut out from the roll paper R, the roll direction, the front / back orientation, the material, the thickness, etc. Therefore, it is possible to further prevent the occurrence of double feeding of the medium M and the occurrence of wrinkles.

[0077] The present invention is not limited to the above-described embodiments, and can be embodied by modifying the components without departing from the spirit of the invention in the implementation stage. Furthermore, various inventions can be formed by appropriately combining the multiple components disclosed in the above-described embodiments. For example, all the components shown in the embodiments may be appropriately combined. Naturally, various modifications and applications are possible without departing from the spirit of the invention. Below, some of the inventions described in the specification of this application are additionally noted.

[0078] [Appendix 1] a loading platform on which the media is loaded; a blower that blows air toward an upstream portion of the loading platform in the supply direction of the media to separate the plurality of media from each other; At least one pair of resistance portions whose mutual spacing in the width direction of the medium perpendicular to the feeding direction gradually increases from the upstream side to the downstream side in the feeding direction, and which contact the upper surface of the uppermost medium on the stacking table; A medium supply device comprising:

[0079] [Appendix 2] The at least one pair of resistance portions is provided on a bottom surface, and the device further includes a pressing sheet that presses down the topmost medium from above. 2. A medium supply device according to claim 1.

[0080] [Appendix 3] The presser sheet has a higher rigidity than the medium when the at least one pair of resistance portions is provided, and at least a portion of the presser sheet is lifted by the air blown by the blower. 3. The medium supply device according to claim 2.

[0081] [Appendix 4] The at least one pair of resistance portions are integrally formed on the pressing sheet. 4. The medium supply device according to claim 2 or 3.

[0082] [Appendix 5] The resistor portion includes a plurality of pairs. 5. A medium supply device according to any one of claims 1 to 4.

[0083] [Appendix 6] a supply roller that feeds the topmost medium in the supply direction; The supply roller has an air guide groove extending in the rotation direction. 6. A medium supply device according to any one of claims 1 to 5.

[0084] [Appendix 7] a supply roller that feeds the topmost medium in the supply direction; The supply roller has a wrinkle prevention groove that extends from the center of the medium in the width direction toward the edge of the medium toward the upstream side in the rotation direction. 6. The medium supply device according to any one of claims 1 to 5.

[0085] [Appendix 8] the supply rollers include a first side supply roller disposed on one side of a center of the medium in the width direction, and a second side supply roller disposed on the other side of the center in the width direction, The first side supply roller and the second side supply roller are capable of adjusting the angle of the rotation axis in the supply direction. 8. The medium supply device according to claim 6 or 7. [Explanation of symbols]

[0086] 1,2 Media supply device 10 Loading platform 11 Rotational axis 12 holes 20 Blower 31,32 Resistance section 40 Retaining sheet 41 bottom 42 Notch 43 Connecting part 50 Supply roller 60 trays 70 Seat support 71 Arm 72 Arm holding part 81 Side fence 82 End Fence 91 Control Unit 92 Memory section 93 Interface section 94 Lifting drive unit 95 Roller drive unit 131,231~233,331~335 Resistance section 440 Retaining sheet 441 Resistance section 531~535 ​​Resistance section 540 Retaining sheet 551 Center supply roller 552 1st side supply roller 553 Second side supply roller 551a,552a,553a Wind guide groove 551b, 552b, 553b Wrinkle prevention groove 551c, 552c, 553c Rotating shaft 554,555 joint A Air D Rotation direction F Supply direction M medium Ma upstream part Mb Downstream central part Mc downstream front part Md downstream rear part R Roll paper Ra Winding core Rb Outer winding W width direction

Claims

1. a loading platform on which the media is loaded; a blower that blows air toward an upstream portion of the loading platform in the supply direction of the media to separate the plurality of media from each other; at least one pair of resistance portions whose mutual spacing in a width direction of the medium perpendicular to the feeding direction gradually increases from the upstream side to the downstream side in the feeding direction, and which contact an upper surface of the uppermost medium on the stacking table; A medium supply device comprising:

2. The at least one pair of resistance portions is provided on a bottom surface, and the device further includes a pressing sheet that presses down the topmost medium from above.

2. The medium supply device according to claim 1.

3. The presser sheet has a higher rigidity than the medium when the at least one pair of resistance portions is provided, and at least a portion of the presser sheet is lifted by the air blown by the blower.

3. The medium supply device according to claim 2.

4. The at least one pair of resistance portions are integrally formed on the pressing sheet.

3. The medium supply device according to claim 2.

5. The resistor portion includes a plurality of pairs.

2. The medium supply device according to claim 1.

6. a supply roller that feeds the topmost medium in the supply direction; The supply roller has an air guide groove extending in the rotation direction.

2. The medium supply device according to claim 1.

7. a supply roller that feeds the topmost medium in the supply direction; The supply roller has a wrinkle prevention groove that extends from the center of the medium in the width direction toward the edge of the medium toward the upstream side in the rotation direction.

2. The medium supply device according to claim 1.

8. the supply rollers include a first side supply roller disposed on one side of a center of the medium in the width direction, and a second side supply roller disposed on the other side of the center in the width direction, The first side supply roller and the second side supply roller are capable of adjusting the angle of the rotation axis in the supply direction.

8. The medium supply device according to claim 6 or 7.

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