Media supply device

Abstract

In a media supply device, a pressing member is provided to press down on the upstream end of the uppermost floating media in the transport direction, thereby preventing floating failures and transport failures. [Solution] The pressing member 60 presses down on the upstream end of the uppermost medium M in the transport direction D, which is lifted by the airflow A1 from the airflow air blowing mechanism 21. The pressing force adjustment mechanism 70 is linked to the movement of the end fence 50 in the transport direction D, and increases the pressing force F1, F2 that the pressing member 60 applies to the upstream end of the uppermost medium M when the end fence 50 is at the second position P2, which is upstream of the first position P1 in the transport direction D, compared to when the end fence 50 is at the first position P1 (F2>F1).

Description

Technical Field

[0001] The present invention relates to a medium supply device including a pressing member that presses the upstream end portion in the conveyance direction of the uppermost medium downward.

Background Art

[0002] Conventionally, a sheet supply device including an end fence that regulates the position of the upstream end of the paper on the paper feed table is known (see, for example, Patent Document 1).

[0003] In addition, in order to improve the operability during sheet stacking, an end pressing member that presses the upper surface of the end of the sheet, and a release mechanism that releases the locking of this end pressing member and moves this end pressing member above the upper surface of the end of the sheet have been proposed (see, for example, Patent Document 2).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in a medium supply device that adsorbs a medium such as a sheet lifted by blowing out floating air to a conveyance mechanism by suction of air, by pressing the upper end side end portion in the conveyance direction of the medium downward with a pressing member, it is possible to prevent double feeding in which the second and subsequent media are conveyed together with the uppermost medium.

[0006] For media with a relatively short length in the transport direction, the transport mechanism and the holding member are closer together. Therefore, if the holding member presses down on the upstream end of the media with strong force, a lifting failure occurs, such as the media not being lifted by the buoyant air or the upstream end of the media sagging significantly and being attracted to the transport mechanism. When such a lifting failure occurs, air transport occurs where the uppermost media is not transported as planned.

[0007] Next, with media that are relatively long in the transport direction, the length of the media upstream of the side fence in the transport direction is longer than the length of the side fence, resulting in insufficient guidance by the side fence and making the floating media prone to skew. However, if the clamping force of the clamping member is weakened to match media that are relatively short in the transport direction, it is not possible to prevent the media from skewing, and transport defects occur after the media is supplied, such as misalignment between the media and the image formation content (misalignment due to skew or positional misalignment in the width direction).

[0008] The objective of the present invention is to prevent floating failures and transport failures in a medium supply device equipped with a pressing member that presses down on the upstream end of the uppermost floating medium in the transport direction. [Means for solving the problem]

[0009] In one embodiment, the media supply device includes a loading platform on which a plurality of media are loaded, a floating air blowing mechanism that blows floating air to make at least the uppermost medium of the plurality of media loaded on the loading platform float, a transport mechanism that transports the uppermost medium in the transport direction, a suction mechanism that sucks air to cause the uppermost medium to adhere to the transport mechanism, an end fence that is movable in the transport direction and restricts the position of the upstream end of the plurality of media in the transport direction, a pressing member that presses the upstream end of the uppermost medium downward, and a pressing force adjustment mechanism that is linked to the movement of the end fence in the transport direction and increases the pressing force of the pressing member that presses the upstream end of the uppermost medium downward when the end fence is in a second position upstream of the first position in the transport direction compared to when the end fence is in a first position. [Effects of the Invention]

[0010] According to the above embodiment, a media supply device equipped with a pressing member that presses down on the upstream end of the uppermost floating media in the transport direction, can prevent floating failures and transport failures. [Brief explanation of the drawing]

[0011] [Figure 1] This is a front view showing an image forming system equipped with a media supply device in one embodiment. [Figure 2] This is a plan view showing an end fence, side fence, etc., in one embodiment. [Figure 3] This figure shows the control configuration of a media supply device according to one embodiment. [Figure 4A] This is a plan view showing a pressing member, a pressing force adjustment mechanism, etc., when loading small-sized media in one embodiment. [Figure 4B] This is a front view showing a pressing member, a pressing force adjustment mechanism, etc., when loading small-sized media in one embodiment. [Figure 5A] This is a plan view showing a pressing member, a pressing force adjustment mechanism, etc., when loading large-sized media in one embodiment. [Figure 5B] It is a front view showing a pressing member, a pressing force adjusting mechanism, etc. when loading a large-sized medium in one embodiment. [Figure 6] It is a front view of a medium supply device showing the relationship of the pressing force when loading a small-sized medium in one embodiment. [Figure 7] It is a front view of a medium supply device showing the relationship of the pressing force when loading a large-sized medium in one embodiment. [Figure 8] It is a plan view showing an end fence, side fences, etc. for explaining the skew of a large-sized medium in one embodiment.

Embodiment for Carrying out the Invention

[0012] Hereinafter, a medium supply device according to an embodiment of the present invention will be described with reference to the drawings.

[0013] FIG. 1 is a front view showing an image forming system 100 including a medium supply device 1 in one embodiment.

[0014] FIG. 2 is a plan view showing an end fence 50, side fences 81, 82, etc.

[0015] FIG. 3 is a diagram showing the control configuration of the medium supply device 1.

[0016] In addition, in FIGS. 1 and 2 and FIGS. 4A to 8 described later, the up-down, front-back, and left-right directions shown are such that the up-down direction is the vertical direction, and the front-back direction and the left-right direction are the horizontal directions. These directions are an example when the conveyance direction D is the right direction.

[0017] The media supply device 1 shown in FIG. 1 supplies the medium M to the image forming unit 110 of the image forming apparatus 101. The media supply device 1 and the image forming apparatus 101 may be separately arranged as part of the image forming system 100, or the media supply device 1 may be arranged as part of the image forming apparatus 101. When the media supply device 1 is arranged as part of the image forming apparatus 101, the image forming apparatus 101 can also be regarded as the image forming system 100. Note that the target for which the media supply device 1 supplies the medium M is not limited to the image forming apparatus 101, and may be other devices such as a conveyance device, a processing device (for example, an inspection device or a post-processing device after image formation). Further, as the medium M, for example, paper is used, but other media M such as film and envelopes may be used. Further, a plurality of the media supply devices 1 may be arranged side by side vertically, and the plurality of media supply devices 1 may supply the medium M to a single device (for example, the image forming apparatus 101).

[0018] As shown in FIG. 1, the media supply device 1 includes a loading table 10, a lifting air blowing mechanism 21, a separating air blowing mechanism 22, a conveyance mechanism 30, a suction mechanism 40, an end fence 50, a pressing member 60, and a pressing force adjusting mechanism 70. Further, as shown in FIG. 2, the media supply device 1 further includes a pair of side fences 81, 82 and a shaft holding portion H. Further, as shown in FIG. 3, the media supply device 1 further includes a control unit 91, a storage unit 92, an interface unit 93, a loading table drive unit 94, and a conveyance mechanism drive unit 95.

[0019] A plurality of (a plurality of) media M are loaded on the loading table 10 shown in FIG. 1. The loading table 10 moves up and down by the drive of the loading table drive unit 94 shown in FIG. 3. For example, when the control unit 91 shown in FIG. 3 detects a decrease in the remaining amount of the medium M based on the detection results of a loading surface detection sensor or a floating state detection sensor (not shown), the control unit 91 controls the loading table drive unit 94 to raise the loading table 10 by the height corresponding to the decrease in the medium M. Thereby, in a state where the lifting air A1 is not blown out, the height of the uppermost medium M among the plurality of media M loaded on the loading table 10 is maintained at a prescribed loading surface height.

[0020] The levitation air blowing mechanism 21 blows out levitation air A1 to levitate at least the topmost medium M among the multiple mediums M loaded on the loading platform 10. For example, the levitation air blowing mechanism 21 is positioned downstream in the transport direction D from the multiple mediums M loaded on the loading platform 10, and blows out levitation air A1 from a duct to levitate multiple mediums M (for example, around 10) including the topmost medium M, which is generated by the operation of a fan. Note that the levitation air blowing mechanism 21 is not limited to being positioned downstream in the transport direction D from the multiple mediums M loaded on the loading platform 10, but may also be positioned on both sides in the width direction (front-to-back direction) of the medium M.

[0021] The separation air blowing mechanism 22 blows out separation air A2 to separate the topmost medium M from the second medium M located below it. For example, the separation air blowing mechanism 22 is positioned downstream in the transport direction D from the multiple mediums M loaded on the loading platform 10, and blows out the separation air A2 generated by the operation of the fan from the duct. It is also preferable that the separation air blowing mechanism 22 be positioned not only downstream in the transport direction D from the multiple mediums M loaded on the loading platform 10, but also on both sides in the width direction (front-to-back direction) of the medium M.

[0022] The conveying mechanism 30 includes a conveying belt 31 and pulleys 32 and 33 over which the conveying belt 31 is stretched. One of the pulleys 32 and 33 is a driving pulley, and the other is a driven pulley. The driving pulley of the pulleys 32 and 33 is rotated by the drive of the conveying mechanism drive unit 95 shown in Figure 3, causing the conveying belt 31 to rotate. As a result, the conveying mechanism 30 conveys the uppermost medium M of the multiple mediums M stacked on the loading platform 10 in the conveying direction D (right side in Figure 1) and hands it over to the register roller pair 130 of the image forming apparatus 101.

[0023] The conveyor belt 31 is provided with multiple through holes (not shown) for passing suction air A3, which is air sucked up by the suction mechanism 40 described later. The conveyor mechanism 30 may have other conveying members such as roller conveyors instead of the conveyor belt 31 as conveying members for conveying the medium M, but it is preferable for the conveyor mechanism 30 to have the conveyor belt 31 as a conveying member because the conveyor belt 31 can suck up and convey the medium M while making surface contact with it.

[0024] The suction mechanism 40 is located, for example, in an area surrounded by the conveyor belt 31 of the conveying mechanism 30. The suction mechanism 40 works by drawing in suction air A3 through a duct via a suction source (e.g., a suction fan) not shown through multiple through holes in the conveyor belt 31, thereby causing the topmost medium M of the multiple mediums M loaded on the loading platform 10 to be attracted to the conveying mechanism 30.

[0025] The end fence 50 is positioned to be movable in the transport direction D and restricts the position of the upstream end of multiple media M in the transport direction D. As shown in Figures 4A to 5B, the end fence 50 has a fence body 51, a fence guide section 52, a fence shaft 53, a guide shaft 54, and a media guide member 55.

[0026] For example, the fence body 51 includes a plate-like portion that extends in the front, back, left, and right directions, two plate-like portions that bend downward from both the front and rear ends and extend in the up, down, left, and right directions, and a portion that bends downward from the right end of the plate-like portion that extends in the front, back, left, and right directions (the downstream end in the conveying direction D). This downwardly bent portion contacts the upstream end of the medium M. At the lower end of this contact portion, there is a bent portion 51a that bends diagonally away from the medium M towards the upstream side in the conveying direction D.

[0027] Furthermore, the fence body 51 is provided with a pivot shaft 51b that pivotably supports the media guide member 55, which will be described later, and a projection 51c that is inserted into the elongated hole 55a of the media guide member 55.

[0028] The fence guide section 52, together with the fence shaft 53 and guide shaft 54 ​​described later, horizontally guides the movement of the fence body 51 in the transport direction D. The fence guide section 52 includes a support plate 52a, fixing screws 52b and 52c, an arc-shaped hole 52d, a gear hole 52e, and a rising section 52f.

[0029] For example, the support plate 52a has an L-shaped plate form, consisting of a plate-like portion that extends in the front, back, left, and right directions, and a plate-like portion that bends downward from its front end and extends in the up, down, left, and right directions.

[0030] One fixing screw 52b secures the area near one end (front end) of the fence shaft 53 in the portion of the support plate 52a that extends in the front, rear, left, and right directions. The other fixing screw 52c secures the area near one end (front end) of the guide shaft 54 ​​in the portion of the support plate 52a that extends in the front, rear, left, and right directions.

[0031] The arc-shaped hole 52d is provided in an arc shape in the portion of the support plate 52a that widens in the front, back, left, and right directions, and guides the slide pin 54b provided at one end of the guide shaft 54, which will be described later.

[0032] The gear hole 52e is a hole in the portion of the support plate 52a that extends in the front, back, left, and right directions, where the sector-shaped gear 73 of the clamping force adjustment mechanism 70, which will be described later, is positioned.

[0033] The rising portion 52f rises at the boundary between the fence body 51 and the support plate 52a, and rotatably supports the sector gear 73.

[0034] As described above, one end of the fence shaft 53 is fixed to the support plate 52a by a fixing screw 52b, and the other end (rear end) is held by the shaft holding part H. This shaft holding part H is fixed to the housing (exterior frame) of the media supply device 1, for example, but it may also be fixed to the housing of the image forming apparatus 101, or the like.

[0035] The guide shaft 54 ​​is positioned parallel to the fence shaft 53, and as described above, one end is fixed to the support plate 52a by a fixing screw 52c, while the other end (rear end) is held by the shaft holding part H.

[0036] Therefore, the fence shaft 53 and the guide shaft 54 ​​rotate in conjunction with the movement of the fence body 51 in the transport direction D. The upper part of one end (front end) of the fence shaft 53 and the guide shaft 54 ​​is provided with D-cut portions 53a and 54a that contact the bottom surface of the support plate 52a.

[0037] The media guide member 55 has a fan-shaped design and guides the media M that protrudes upstream in the transport direction D when the loading platform 10 is raised to the correct position. The media guide member 55 is pivotably supported by the aforementioned pivot shaft 51b of the fence body 51. The media guide member 55 is also provided with an arc-shaped elongated hole 55a. The media guide member 55 is supported by the fence body 51 when the aforementioned projection 51c of the fence body 51 is inserted into the elongated hole 55a. The media guide member 55 is biased clockwise in Figure 4B by a torsion spring, and when the lower end of the media guide member 55 contacts the loading platform 10, it rises while rotating (oscillating) counterclockwise against the biasing force of the torsion spring.

[0038] The pressing member 60 presses down on the upstream end of the uppermost medium M loaded on the loading platform 10 in the transport direction D. As shown in Figures 4B and 5B, the pressing member 60 has, for example, an L-shape when viewed from the front, and its bottom surface contacts the upper surface of the upstream end of the medium M. The pressing member 60 can also be called a pressing block, pressing plate, or pusher. The upstream end of the medium M in the transport direction D that the pressing member 60 presses down may be located at a distance from the upstream periphery of the medium M in the transport direction D. Furthermore, the bottom surface of the pressing member 60 should be located below the bottom surface of the transport mechanism 30 (the suction surface of the medium M).

[0039] The clamping force adjustment mechanism 70 adjusts the clamping force F1 and F2 applied by the clamping member 60 to the uppermost medium M when the end fence 50 is at the second position P2 (see Figures 5A and 5B), which is upstream of the first position P1 in the transport direction D, compared to when the end fence 50 is at the first position P1 (see Figures 4A and 4B) (clamping force F1 < clamping force F2). The first position P1 of the end fence 50 is the position that restricts the position of the upstream end of a small-sized medium M1, which has a relatively short length in the transport direction D of the medium M. The second position P2 of the end fence 50 is the position that restricts the position of the upstream end of a large-sized medium M2, which has a relatively long length in the transport direction D of the medium M. Here, the small-sized medium M1 is, for example, an A4 sheet of paper stacked with its short side parallel to the transport direction D, and the large-sized medium M2 is, for example, an A3 sheet of paper stacked with its long side parallel to the transport direction D. Note that the small-sized medium M1 and the large-sized medium M2 may be two mediums of the same size M, but with different orientations when stacked.

[0040] The clamping force adjustment mechanism 70 includes an elastic body 71, a support member 72, and a sector-shaped gear 73, which is an example of an interlocking member.

[0041] The elastic body 71 presses the retaining member 60 downward. The elastic body 71 is, for example, a compression coil spring that extends vertically and whose lower end is connected to the retaining member 60. The elastic body 71 is not limited to a compression coil spring; it may be other springs, rubber, or the like.

[0042] The support member 72 is connected to the upper end of the elastic body 71 and supports the elastic body 71 at this upper end. The support member 72 has teeth that mesh with the sector gear 73 and moves up and down as the sector gear 73 rotates. The support member 72 can also be called a pressure-adjustable member, a lifting member, etc. It is preferable that the support member 72 has a hole that passes through the upper part of the retaining member 60.

[0043] As the end fence 50 moves in the conveying direction D and the fence shaft 53 rotates counterclockwise in Figure 4A, the sector gear 73 is pressed in the conveying direction D by the front end of the fence shaft 53 and rotates counterclockwise in Figure 4B, raising the support member 72. When the end fence 50 moves in the opposite direction to the conveying direction D, the sector gear 73 is no longer pressed by the front end of the fence shaft 53 as the fence shaft 53 rotates clockwise in Figure 5A, and rotates clockwise in Figure 5B, for example, due to the elastic force of a torsion spring, lowering the support member 72. Note that the torsion spring can be omitted if the front end of the fence shaft 53 and the sector gear 73 are connected.

[0044] The side fences 81 and 82 shown in Figure 2 restrict the position of the ends of the medium M in the width direction (front-to-back direction) perpendicular to the transport direction D. The side fences 81 and 82 should be positioned to be movable in the width direction according to the size of the medium M. Note that the side fences 81 and 82 are not shown in Figure 1.

[0045] The control unit 91 shown in Figure 3 has a processor (e.g., CPU: Central Processing Unit) that functions as an arithmetic processing unit that controls the operation of the entire media supply device 1. For example, it reads and executes a predetermined program from the storage unit 92 or from a storage medium (non-transient computer-readable recording medium) that can be attached to or removed from the media supply device 1. By executing this program, the control unit 91 controls the operation of each part of the media supply device 1. In cases where the media supply device 1 is integrated with the image forming apparatus 101, the control unit of the image forming apparatus 101 may also serve as the control unit 91 of the media supply device 1.

[0046] The memory unit 92 includes, for example, a ROM (Read Only Memory), which is a read-only semiconductor memory in which a predetermined control program is pre-recorded, and a RAM (Random Access Memory), which is a semiconductor memory that can be written to and read at any time and used as a working memory area as needed when the processor executes various control programs.

[0047] The interface unit 93 exchanges various types of information with external devices such as the image forming apparatus 101. For example, the interface unit 93 receives information such as requests for supply or stop supply of media M from the control unit of the image forming apparatus 101, and the control unit 91 controls the operation of each part of the media supply device 1 based on this information.

[0048] The loading platform drive unit 94 has an actuator such as a motor that raises and lowers the loading platform 10.

[0049] The transport mechanism drive unit 95 has an actuator such as a motor that rotates the drive pulley, which is one of the pulleys 32 and 33 of the transport mechanism 30.

[0050] Next, we will describe the image forming apparatus 101 shown in Figure 1.

[0051] The image forming apparatus 101 comprises an image forming unit 110, a transport unit 120, and a pair of registration rollers 130. Figure 1 shows the transport path from the transport mechanism 30 of the media supply device 1 to the image forming unit 110 of the image forming apparatus 101, indicated by a dashed line. In this transport path, the media M is preferably guided by a pair of upper and lower plate-shaped transport guides (not shown).

[0052] The image forming unit 110 has, for example, line-head type inkjet heads (not shown) for each color used in image formation. The image forming method of the image forming unit 110 may be any image forming method other than the inkjet method.

[0053] The transport unit 120 is positioned opposite the image forming unit 110. The transport unit 120 transports the medium M by a transport belt while, for example, adsorbing the medium M.

[0054] The registration roller pair 130 corrects the skewness of the medium M supplied from the medium supply device 1 by abutting against it, and then transports the medium M toward the image forming unit 110 and the transport unit 120.

[0055] In the above-described image forming apparatus 101, the medium M on which image formation has been performed by the image forming unit 110 is discharged to a discharge unit (not shown). Further, when image formation is performed on both sides of the medium M, the medium M on which image formation has been performed on one side by the image forming unit 110 is conveyed back to the image forming unit 110 through a circulation path (not shown), and image formation on the remaining surface is performed by the image forming unit 11].

[0056] As shown in FIG. 6, when the medium M is the small-size medium M1 and the end fence 50 is at the first position P1, the end fence 50 is located on the downstream side in the conveying direction D as compared with the case where it is at the second position P2 shown in FIG. 7. In this case, since the sector gear 73 raises the support member 72 more when the end fence 50 is at the second position P2, in the state where the pressing member 60 presses the upstream end of the medium M (see FIG. 4B), the elastic body 71 stretches. Therefore, the force with which the elastic body 71 presses the pressing member 60 downward becomes weaker, and the pressing force F1 with which the pressing member 60 presses the upstream end of the medium M downward becomes weaker (F1 < F2). Therefore, even when the pressing member 60 approaches the conveying mechanism 30, due to the suction of the suction air A3 by the suction mechanism 40, the sag on the upstream side in the conveying direction D of the small-size medium M1 becomes smaller, and the small-size medium M1 is more likely to be adsorbed by the conveying mechanism 30.

[0057] Note that the pressing force F1 of the pressing member 60 when the end fence 50 is at the first position P1 is preferably weaker than the suction force F10 of the suction mechanism 40. Further, this pressing force F1 is preferably stronger than the levitation force F20, which is the vertical upward component of the levitation air A1 blown out by the levitation air blowing mechanism 21.

[0058] As shown in Figure 7, when the medium M is a large-size medium M2 and the end fence 50 is in the second position P2, the sector gear 73 lowers the support member 72 more than when the end fence 50 is in the first position P1. Therefore, when the pressing member 60 is pressing the upstream end of the medium M (see Figure 5B), the elastic body 71 is compressed. Consequently, the force with which the elastic body 71 presses the pressing member 60 downward becomes stronger than when the end fence 50 is in the first position P1, and the pressing force F2 with which the pressing member 60 presses the upstream end of the medium M downward becomes stronger (F2 > F1). Therefore, as shown in Figure 8, it is possible to prevent the diagonal movement of the large-size medium M2, which is likely to occur due to the large-size medium M2 extending longer upstream of the side fences 81, 82 in the conveying direction D, i.e., the diagonal movement of the large-size medium M2 being attracted to the conveying mechanism 30 at an angle, as shown by the dashed line M2S.

[0059] Furthermore, when the end fence 50 is in the second position P2, the pressing force F2 of the pressing member 60 should be stronger than the suction force F10 of the suction mechanism 40. However, if the pressing force F2 is too strong, the uppermost medium M will be pinched between the pressing member 60 and the second and subsequent mediums M, hindering transport. Therefore, the pressing force F2 should be strong enough not to hinder the transport of the uppermost medium M by the transport mechanism 30. Also, when the end fence 50 is in the second position P2, the pressing force F2 of the pressing member 60 should be stronger than the buoyancy force F20, which is the vertically upward component of the buoyancy air A1 blown out by the buoyancy air blowing mechanism 21, similar to the pressing force F1.

[0060] The following outline of the supply operation of the media supply device 1 will be explained with reference to Figures 6 and 7.

[0061] First, as shown in Figures 6 and 7, with the floating air blowing mechanism 21 blowing out floating air A1, the separating air blowing mechanism 22 blowing out separated air A2, and the suction mechanism 40 sucking in suction air A3 all operating, the topmost medium M among the multiple mediums M loaded on the loading platform 10 is attracted to the conveyor belt 31.

[0062] When the topmost medium M is attracted to the conveyor belt 31, the control unit 91 stops the blowing of levitation air A1 by the levitation air blowing mechanism 21. With the levitation air A1 stopped in this way, the second and subsequent mediums M that are not attracted to the conveyor mechanism 30 fall and return to their stacked state on the loading platform 10.

[0063] Furthermore, the control unit 91 initiates the transport of the uppermost medium M by the transport mechanism 30 through drive control of the transport mechanism drive unit 95. The medium M transported by the transport mechanism 30 is brought into contact with the register roller pair 130 shown in Figure 1, and then transported by the register roller pair 130 toward the transport unit 120, where image formation is performed by the image forming unit 110.

[0064] In the media supply device 1, after the transport mechanism 30 has started transporting the top medium M, the control unit 91 restarts the blowing of floating air A1 by the floating air blowing mechanism 21 in order to attract the next medium M (the second medium M) to the transport mechanism 30. The blowing of separated air A2 by the separated air blowing mechanism 22 is preferably performed continuously while transporting multiple mediums M, and the suction of suction air A3 by the suction mechanism 40 is preferably temporarily stopped each time a medium M is transported and restarted when the second medium M is attracted to the transport mechanism 30.

[0065] In the above explanation, a sector gear 73 was given as an example of an interlocking member of the clamping force adjustment mechanism 70, that is, an interlocking member that raises the support member 72 in conjunction with the downstream movement of the end fence 50 in the transport direction D, and lowers the support member 72 in conjunction with the upstream movement of the end fence 50 in the transport direction D. However, the interlocking member is not limited to a sector gear 73, as long as it raises and lowers the support member 72 in conjunction with the movement of the end fence 50 in the transport direction D, for example, by being linked to the rotation of the fence shaft 53.

[0066] Furthermore, the clamping force adjustment mechanism 70 may omit the elastic body 71 and have the support member 72 press the clamping member 60 downward, or it may only press the clamping member 60 downward when the end fence 50 is in the second position P2 of the two positions P2 (first position P1 and second position P2). In these cases as well, the clamping force adjustment mechanism 70 can increase the clamping force F2 of the clamping member 60 when the end fence 50 is in the second position P2 compared to when it is in the first position P1.

[0067] Furthermore, the clamping force adjustment mechanism 70 increases the clamping forces F1 and F2 when the end fence 50 is in the second position P2, which is upstream in the transport direction D, compared to when the end fence 50 is in the first position P1. It can also be said that the clamping forces F1 and F2 increase as the end fence 50 moves further upstream in the transport direction D. Thus, it is desirable that the clamping forces F1 and F2 increase as the end fence 50 moves further upstream in the transport direction D. Note that the configuration of the media supply device 1 (each part including the clamping force adjustment mechanism 70 and the end fence 50) is merely an example and can be changed or omitted as appropriate.

[0068] In the embodiment described above, the media supply device 1 comprises a loading platform 10, a levitation air blowing mechanism 21, a transport mechanism 30, a suction mechanism 40, an end fence 50, a pressing member 60, and a pressing force adjustment mechanism 70. Multiple media M are loaded onto the loading platform 10. The levitation air blowing mechanism 21 blows out levitation air A1 to levitate at least the uppermost media M among the multiple media M loaded on the loading platform 10. The transport mechanism 30 transports the uppermost media M in the transport direction D. The suction mechanism 40 sucks air (suction air A3) to cause the uppermost media M to adhere to the transport mechanism 30. The end fence 50 is movably positioned in the transport direction D and restricts the position of the upstream end of the multiple media M in the transport direction D. The pressing member 60 presses down on the upstream end of the uppermost media M. The pressing force adjustment mechanism 70 is linked to the movement of the end fence 50 in the transport direction D, and increases the pressing force F1, F2 that the pressing member 60 applies to the upstream end of the uppermost medium M when the end fence 50 is at the second position P2, which is upstream of the first position P1 in the transport direction D, compared to when the end fence 50 is at the first position P1 (F1>F2).

[0069] Therefore, first, the pressing member 60 presses down on the upstream end of the uppermost medium M, thereby suppressing double feeding, where the second and subsequent mediums M are transported together with the uppermost medium M by the transport mechanism 30. Incidentally, when a medium M with a relatively short length in the transport direction D (for example, a small-sized medium M1) is loaded on the loading platform 10, the end fence 50 is in the first position P1, and the transport mechanism 30 and the pressing member 60 are relatively close. In this case, by making the pressing force F1 of the pressing member 60 relatively weaker, it is possible to prevent lifting failures such as the medium M not being lifted by the levitation air A1, or the upstream side of the medium M being sucked into the transport mechanism 30 while sagging significantly. Also, when a medium M with a relatively long length in the transport direction D (for example, a large-sized medium M2) is loaded on the loading platform 10, the end fence 50 is in the second position P2, and the transport mechanism 30 and the pressing member 60 are relatively far apart. In this case, even if the pressing force F2 of the pressing member 60 is relatively strong, levitation failures are less likely to occur. Furthermore, by relatively increasing the pressing force F2 of the pressing member 60, it is possible to suppress the skew of the large-size medium M2 (see the skewed large-size medium M2S shown by the dashed line in Figure 8), which is likely to occur because the large-size medium M2 extends further upstream in the transport direction D than the side fences 81, 82. As a result, transport failures such as misalignment between the medium M and the image formation content (misalignment due to skew or positional misalignment in the width direction) after the medium M is supplied can be prevented. Thus, according to this embodiment, levitation failures and transport failures can be prevented in a medium supply device 1 equipped with a pressing member 60 that presses down on the upstream end of the uppermost levitated medium M in the transport direction D.

[0070] Furthermore, in this embodiment, the pressing force adjustment mechanism 70 includes an elastic body 71 that presses the pressing member 60 downward, a support member 72 that supports the upper end of the elastic body 71, and a fan-shaped gear 73 (an example of an interlocking member) that raises the support member 72 in conjunction with the downstream movement of the end fence 50 in the transport direction D, and lowers the support member 72 in conjunction with the upstream movement of the end fence 50 in the transport direction D.

[0071] As a result, the pressing forces F1 and F2 of the pressing member 60 can be adjusted with a simple configuration using the elastic body 71.

[0072] Further, in the present embodiment, the pressing force adjustment mechanism 70 makes the pressing force F1 weaker than the suction force F10 by the suction mechanism 40 (F1 < F10) when the end fence 50 is in the first position P1, and makes the pressing force F2 stronger than the suction force F10 (F2 > F10) when the end fence 50 is in the second position P2.

[0073] As a result, when the end fence 50 is in the first position P1, floating defects can be more reliably prevented, and when the end fence 50 is in the second position P2, conveyance defects can be more reliably prevented.

[0074] Note that the present invention is not limited to the above-described embodiment as it is, and the components can be modified and embodied without departing from the gist thereof at the implementation stage. Also, various inventions can be formed by appropriately combining a plurality of components disclosed in the above-described embodiment. For example, all the components shown in the embodiment may be appropriately combined. Needless to say, various modifications and applications are possible within the scope not departing from the gist of the invention. Hereinafter, the invention described in the claims of the present application at the time of filing is appended.

[0075] [Appended Note 1] A loading table on which a plurality of media are loaded, A floating air blowing mechanism that blows out floating air for floating at least the uppermost one of the plurality of media loaded on the loading table, A conveyance mechanism that conveys the uppermost medium in the conveyance direction, A suction mechanism that sucks air to adsorb the uppermost medium to the conveyance mechanism, An end fence that is disposed movably in the conveyance direction and regulates the position of the upstream end portion of the plurality of media in the conveyance direction, A pressing member that presses the upstream end portion of the uppermost medium downward, A pressing force adjustment mechanism that, in conjunction with the movement of the end fence in the transport direction, increases the pressing force applied by the pressing member to the uppermost medium's upstream end when the end fence is in a second position upstream of the first position in the transport direction compared to when the end fence is in a first position; A media supply device characterized by comprising the following features.

[0076] [Note 2] The pressing force adjustment mechanism includes an elastic body that presses the pressing member downward, a support member that supports the upper end of the elastic body, and an interlocking member that raises the support member in conjunction with the downstream movement of the end fence in the conveying direction, and lowers the support member in conjunction with the upstream movement of the end fence in the conveying direction. A media supply device as described in Appendix 1, characterized by the features described herein.

[0077] [Note 3] The clamping force adjustment mechanism makes the clamping force weaker than the suction force of the suction mechanism when the end fence is in the first position, and makes the clamping force stronger than the suction force when the end fence is in the second position. A media supply device as described in Appendix 1 or 2, characterized by the above. [Explanation of Symbols]

[0078] 1 Media supply device 10 Loading platform 21. Levitation Air Blowing Mechanism 22 Separation air blowing mechanism 30 Conveying mechanism 31 Conveyor belt 32,33 Pulley 40 Suction mechanism 50 End Fence 51 Fence body 51a Bend part 51b Oscillating axis 51c protrusion 52 Fence guide section 52a Support plate 52b, 52c Fixing screws 52d Arc hole 52e gear hole 52f Rising section 53 Fence axis 53a D-cut section 54 Guide axis 54a D-cut section 54b Slide pin 55 Media guide member 55a long hole 60 Retaining member 70. Pressure adjustment mechanism 71 Elastic body 72 Support member 73 Sector-shaped gear (interlocking component) 81,82 Side fence 91 Control Unit 92 Memory section 93 Interface section 94 Loading platform drive unit 95 Conveyor mechanism drive unit 100 Image Forming Systems 101 Image forming apparatus 110 Image forming unit 120 Conveying section 130 Resistola vs A1 Floating Air A2 Separation air A3 Suction Air D Conveying direction F1, F2 pressure F10 suction power F20 lift H-axis holding part M medium M1 Small Size Media M2 Large Size Media M2S skewed large-size media P1 1st position P2 2nd position

Claims

1. A loading platform on which multiple media can be loaded, A floating air blowing mechanism blows floating air to make at least the topmost medium among the multiple media loaded on the loading platform float, A transport mechanism for transporting the uppermost medium in the transport direction, A suction mechanism that causes the uppermost medium to be adsorbed onto the transport mechanism by sucking in air, An end fence is arranged to be movable in the transport direction and restricts the position of the upstream end of the plurality of media in the transport direction, A pressing member that presses the upstream end of the uppermost medium downward, A pressing force adjustment mechanism is provided that, in conjunction with the movement of the end fence in the transport direction, increases the pressing force applied by the pressing member to the uppermost medium's upstream end when the end fence is in a second position upstream of the first position in the transport direction compared to when the end fence is in a first position. A media supply device characterized by comprising the following features.

2. The pressing force adjustment mechanism includes an elastic body that presses the pressing member downward, a support member that supports the upper end of the elastic body, and an interlocking member that raises the support member in conjunction with the downstream movement of the end fence in the conveying direction, and lowers the support member in conjunction with the upstream movement of the end fence in the conveying direction. The media supply device according to claim 1, characterized in that it is a media supply device.

3. The clamping force adjustment mechanism makes the clamping force weaker than the suction force of the suction mechanism when the end fence is in the first position, and makes the clamping force stronger than the suction force when the end fence is in the second position. A media supply device according to claim 1 or 2, characterized in that it is the same as described in claim 1 or 2.

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