Sheet feeding device

Abstract

To provide a sheet feeder capable of expanding an adjustment range of an air volume of air blown out toward a sheet bundle.SOLUTION: The side floating air outlet 16 blows out side floating air A3 toward the sheet bundle from the side of the sheet bundle. In the side floating air passage 33, air A1 flows toward the side floating air outlet 16. The adjustment mechanism 34 adjusts the air volume of the side floating air A1 blown out from the side floating air outlet 16 by allowing a part of the air A3 to flow out to the outside in the middle of the side floating air path 33.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a sheet feeding device. [Background technology]

[0002] A known sheet supplying device for supplying sheets is one that blows air toward a stack of sheets stacked on a paper feed tray to lift the sheets, and then uses a suction and conveyance means to suction and convey the topmost (uppermost) sheet of the lifted sheets to feed it to a printing device (see Patent Document 1).

[0003] In this type of paper feeder, the volume of air blown toward the stack of sheets is adjusted by adjusting the volume of air from the fan, which is the air generator, depending on the paper type and size. If the air volume is not appropriate for the paper type and size, the paper may behave erratically, resulting in paper feeding problems. For example, if the air volume is too large, there is a risk of multiple sheets overlapping and being attracted to the suction conveying means and transported, resulting in double feeding. Furthermore, if the air volume is too small, there is a risk of sheets not floating sufficiently and being attracted to the suction conveying means, resulting in empty transport, where the sheets are not transported. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-182651 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in paper feeders such as those described above, the fan's adjustable range of airflow may be insufficient to accommodate a wide range of paper types and sizes, particularly when inexpensive fans with a relatively narrow adjustable range of airflow are used to reduce costs.

[0006] For example, if a fan capable of generating an air volume sufficient to lift the largest size of thick paper is used, even when the fan's air volume is adjusted to the minimum, the air volume will be greater than the appropriate air volume for each size of thin paper or regular paper, and may not be able to handle thin paper or regular paper.

[0007] For this reason, there has been a demand for a technology that can expand the range of adjustment for the volume of air blown toward the stack of sheets.

[0008] The present invention has been made in view of the above, and has an object to provide a sheet feeding device that can expand the range of adjustment of the volume of air blown toward a sheet stack. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the sheet feeding device of the present invention is characterized by comprising an air outlet that blows air from the side of the sheet stack toward the sheet stack, an air path through which the air flows toward the air outlet, and an adjustment mechanism that adjusts the volume of air blown out from the air outlet by causing a portion of the air to flow outside midway through the air path. [Effects of the Invention]

[0010] According to the sheet feeding device of the present invention, the range of adjustment of the volume of air blown toward the sheet stack can be expanded. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic configuration diagram of a paper feeder according to an embodiment; [Figure 2] FIG. 2 is a control block diagram of the paper feeder shown in FIG. [Figure 3] 2 is an enlarged view of the vicinity of a conveying unit of the paper feeding device shown in FIG. [Figure 4] 2 is an enlarged view of the vicinity of a main floating air outlet of the paper feeder shown in FIG. 1. [Figure 5] 2 is a partial enlarged view of a side fence of the paper feeder shown in FIG. 1. FIG. [Figure 6]10 is an enlarged view of the adjustment mechanism and its vicinity with the opening of the side floating air path of the side air unit open. FIG. [Figure 7] 10 is an enlarged view of the vicinity of the adjustment mechanism with the opening of the side floating air path of the side air unit closed. FIG. [Figure 8] FIG. 10 is a diagram illustrating an adjustment table. [Figure 9] 10A and 10B are views showing a lever for manually operating an opening / closing portion of the adjustment mechanism. [Figure 10] FIG. 10 is a diagram showing an adjustment mechanism provided in the side separation air path. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts and components are designated by the same or equivalent reference numerals throughout the drawings.

[0013] The following embodiments are examples of devices that embody the technical idea of ​​the present invention, and the technical idea of ​​the present invention does not limit the materials, shapes, structures, arrangements, etc. of each component to those described below. The technical idea of ​​the present invention can be modified in various ways within the scope of the claims.

[0014] FIG. 1 is a schematic configuration diagram of a paper feeder according to an embodiment of the present invention. FIG. 2 is a control block diagram of the paper feeder shown in FIG. 1. FIG. 3 is an enlarged view of the vicinity of the transport unit of the paper feeder shown in FIG. 1. FIG. 4 is an enlarged view of the vicinity of the main floating air outlet of the paper feeder shown in FIG. 1. FIG. 5 is a partial enlarged view of a side fence of the paper feeder shown in FIG. 1. FIG. 6 is an enlarged view of the vicinity of the adjustment mechanism with the opening of the side floating air path of the side air unit opened. FIG. 7 is an enlarged view of the vicinity of the adjustment mechanism with the opening of the side floating air path of the side air unit closed. In the following description, the direction perpendicular to the plane of the paper in FIG. 1 is the front-to-rear direction, and the front direction of the paper is the forward direction. Furthermore, the up, down, left, and right directions of the plane of the paper in FIG. 1 are the up, down, left, and right directions.

[0015] 1 to 4, a paper feeder (corresponding to a sheet supplying device) 1 according to this embodiment includes a paper feed table 2, an elevation motor 3, a paper feed guide plate 4, a separation gate 5, side fences 6A and 6B, an end fence 7, a main lifting mechanism 8, a main separation mechanism 9, side air units 10A and 10B, a conveying section 11, an upper limit sensor 12, and a control section 13. Note that the alphabetical subscripts of the reference numerals for the side fences 6A, 6B, etc. may be omitted to refer to them collectively.

[0016] The paper feeder 1 is a device that feeds paper (corresponding to a sheet) P to a printing unit (not shown) of a printing device. The direction from left to right in Fig. 1 is the direction in which paper P is conveyed by conveying unit 11 during paper feeding operation. In the following description, upstream and downstream refer to upstream and downstream in the direction in which paper P is conveyed by conveying unit 11.

[0017] The paper feed tray 2 is configured to be able to move up and down and to hold sheets of paper P to be used for printing.

[0018] The lifting motor 3 lifts and lowers the sheet feed tray 2 .

[0019] The paper feed guide plate 4 is a member that regulates the position of the downstream end (right end) of the paper P on the paper feed tray 2. The paper feed guide plate 4 is located near the downstream side of the paper feed tray 2 and below the downstream end of the belt unit 41, which will be described later.

[0020] The separation gate 5 is a member that blocks all of the sheets P of the stack of sheets (corresponding to a stack of sheets) PT on the paper feed table 2 that have been floated by the main floating mechanism 8 and the side air units 10A and 10B, except for the topmost sheet P that has been adsorbed to the conveyance section 11. Two separation gates 5 are installed spaced apart from each other in the front-to-rear direction near the lower downstream end of the conveyance section 11. Here, the stack of sheets PT is made up of multiple sheets P stacked on top of each other on the paper feed table 2.

[0021] The side fences 6A and 6B are members that regulate the front-rear position of the paper P on the paper feed tray 2. The side fences 6A and 6B are arranged spaced apart from each other in the front-rear direction.

[0022] As shown in Figures 4 and 5, the side fence 6 is formed with a side floating air outlet (corresponding to an outlet and a floating air outlet) 16 and a side separation air outlet (corresponding to an outlet and a separation air outlet) 17. The side fence 6 is also provided with a straightening member 18. Figure 5 is a view of the front side fence 6A as seen from the rear.

[0023] The side floating air outlet 16 is an outlet that blows out the side floating air generated by the side air unit 10 toward the paper stack PT. The side separation air outlet 17 is an outlet that blows out the side separation air generated by the side air unit 10 toward the paper stack PT.

[0024] The rectifying member 18 is a member that attracts the uppermost sheet P of the sheets P of the stack of sheets PT on the sheet feed tray 2 that have been floated by the main floating mechanism 8 and the side air units 10A, 10B, and causes side separation air to flow between the uppermost sheet P and the second-highest sheet P. The rectifying member 18 is attached to the inner surface (the sheet feed tray 2 side) of the side fence 6, along the upper edge of the side separation air outlet 17. The rectifying member 18 is inclined so that it becomes higher toward the center of the sheet feed tray 2 in the front-to-rear direction.

[0025] The end fence 7 is a member that regulates the position of the upstream end (left end) of the paper P on the paper feed tray 2. The end fence 7 is disposed above the paper feed tray 2. The end fence 7 is configured to be movable in the left-right direction.

[0026] The main floating mechanism 8 blows main floating air from the downstream side toward the stack of sheets PT on the sheet feed tray 2 to float the sheets P. The main floating mechanism 8 is disposed near the downstream side of the sheet feed tray 2. The main floating mechanism 8 includes a main floating fan 21, a shutter 22, and two main floating air outlets 23.

[0027] The main levitation fan 21 generates main levitation air.

[0028] The shutter 22 switches on and off the blowing of main floating air from the main floating air outlet 23. When the main floating fan 21 is driven, if the shutter 22 is open, the main floating air is blown out from the main floating air outlet 23, and if the shutter 22 is closed, the blowing of main floating air from the main floating air outlet 23 is stopped.

[0029] The main floating air outlets 23 are outlets for main floating air generated by driving the main floating fan 21. The two main floating air outlets 23 are arranged near the lower downstream end of the transfer section 11 and spaced apart from each other in the front-to-rear direction.

[0030] The main separation mechanism 9 injects main separation air from the downstream side between the topmost sheet P and the second topmost sheet P, which have been floated by the main floating mechanism 8 and the side air units 10A, 10B and adsorbed to the conveyance section 11. The main separation mechanism 9 includes a main separation fan 26 and two main separation air outlets 27.

[0031] The main separation fan 26 generates the main separation air.

[0032] The main separation air outlets 27 are outlets for main separation air generated by driving the main separation fan 26. The two main separation air outlets 27 are arranged spaced apart from each other in the front-to-rear direction near the lower downstream end of the conveying section 11. The main separation air outlets 27 blow out the main separation air upward toward the conveying section 11.

[0033] The side air unit 10A blows side floating air from the front side toward the stack of sheets PT on the sheet feed tray 2 to float the sheets P. The side air unit 10A also blows side separation air from the front side between the topmost sheet P and the second-highest sheet P that have floated from the stack of sheets PT on the sheet feed tray 2 and been adsorbed to the conveyance section 11, to separate the topmost sheet P from the sheets P following the second-highest sheet P. The side air unit 10A is installed on the side fence 6A.

[0034] As shown in Figures 1, 2, and 4, the side air unit 10A includes a side fan 31, a side common air path 32, a side floating air path (corresponding to the air path and the floating air path) 33, an adjustment mechanism 34, a shutter 35, and a side separation air path (corresponding to the air path and the separation air path) 36.

[0035] The side fan 31 is a common source of side floating air and side separation air. The side fan 31 is connected to the side common air path 32. In this embodiment, an inexpensive fan with a relatively narrow range of air volume adjustment is used as the side fan 31 to reduce costs, etc. Specifically, the side fan 31 in this embodiment can generate a relatively large air volume that is sufficient to float thick paper of various sizes with the side floating air, but it cannot adjust the side floating air volume to a small volume appropriate for floating thin paper and plain paper.

[0036] The side common air path 32 is a path common to the air flowing from the side fan 31 to the side floating air outlet 16 and the air flowing from the side fan 31 to the side separated air outlet 17 .

[0037] The side floating air path 33 is a path through which air flows from the side common air path 32 toward the side floating air outlet 16. One end of the side floating air path 33 is connected to the side common air path 32, and the other end is connected to the side floating air outlet 16.

[0038] The adjustment mechanism 34 adjusts the volume of side floating air blown out from the side floating air outlet 16 by causing a portion of the air to flow out midway along the side floating air path 33. The adjustment mechanism 34 includes an opening 37 formed midway along the side floating air path 33, an opening / closing unit 38, and an opening / closing drive unit 39.

[0039] The opening 37 is for allowing a portion of the air from the side fan 31 that flows through the side floating air path 33 to flow out to the outside.

[0040] The opening / closing unit 38 opens and closes the opening 37. When the opening / closing unit 38 opens the opening 37, as shown in Fig. 6, a portion of the air A1 from the side fan 31 flowing through the side floating air path 33, that is, air A2, flows out from the opening 37, and the remaining air is blown out from the side floating air outlet 16 as side floating air A3. When the opening / closing unit 38 closes the opening 37, as shown in Fig. 7, no air flows out from the opening 37, and the air from the side fan 31 flowing through the side floating air path 33 is blown out from the side floating air outlet 16 as side floating air A3.

[0041] The opening / closing drive unit 39 drives the opening / closing unit 38. The opening / closing drive unit 39 is configured to adjust the position of the opening / closing unit 38 in the vertical direction to adjust the degree of opening of the side floating air path 33. The degree of opening of the side floating air path 33 indicates the ease with which air flows out of the opening 37. When the opening / closing unit 38 closes the opening 37, the degree of opening of the side floating air path 33 is 0%. The farther the opening / closing unit 38 is from the opening 37, the greater the degree of opening of the side floating air path 33. For a given air volume of the side fan 31, the greater the degree of opening of the side floating air path 33, the greater the volume of air A2 flowing out of the opening 37 and the smaller the volume of side floating air A3 blown out of the side floating air outlet 16. The opening / closing drive unit 39 is configured using a solenoid or the like.

[0042] The shutter 35 switches on and off the blowing of side floating air from the side floating air outlet 16. When the side fan 31 is running, when the shutter 35 is open, side floating air is blown out from the side floating air outlet 16, and when the shutter 35 is closed, the blowing of side floating air from the side floating air outlet 16 is stopped. The shutter 35 is arranged in the side floating air path 33, closer to the side common air path 32 than the opening 37.

[0043] The side separated air path 36 is a path through which air flows from the side common air path 32 toward the side separated air outlet 17. One end of the side separated air path 36 is connected to the side common air path 32, and the other end is connected to the side separated air outlet 17.

[0044] The side air unit 10B blows side floating air from the rear side toward the sheet stack PT on the sheet feed tray 2. The side air unit 10B also blows side separation air from the rear side of the sheet stack PT on the sheet feed tray 2 between the topmost sheet P that has floated from the sheet stack PT and been adsorbed to the conveyance section 11 and the second-highest sheet P. The side air unit 10B is installed on the side fence 6B.

[0045] Like the side air unit 10A, the side air unit 10B includes a side fan 31, a side common air path 32, a side floating air path 33, an adjustment mechanism 34, a shutter 35, and a side separated air path 36. The side air unit 10B has a configuration in which the side air unit 10A is inverted in the front-to-rear direction. The side air unit 10B has the same configuration as the side air unit 10A, except that it is inverted in the front-to-rear direction.

[0046] The transport unit 11 uses air suction to adsorb and transport the uppermost sheet P of sheets P floated by the main floating mechanism 8 and side air units 10A and 10B. As shown in FIGS. 1 to 4, the transport unit 11 includes two belt units 41, a transport motor 42, a chamber 43, and a suction fan 44. Note that side fences 6A and 6B and side air units 10A and 10B are not shown in FIG. 3.

[0047] The belt unit 41 adsorbs and holds the paper P and transports it. The two belt units 41 are arranged side by side in the front-to-rear direction. The belt unit 41 is arranged straddling the right end of the paper feed tray 2 in the left-to-right direction. The belt unit 41 includes a transport belt 46, a drive roller 47, and a driven roller 48.

[0048] The conveyor belt 46 is a circular belt that is stretched over a drive roller 47 and a driven roller 48. A plurality of belt holes 46a are formed around the entire circumference of the conveyor belt 46. The conveyor belt 46 attracts and holds the paper P on a conveying surface 46b, which is the lower surface of the conveyor belt 46, by an attraction force generated in the belt holes 46a by driving the suction fan 44. With the paper P attracted and held, the conveyor belt 46 rotates (moves endlessly) by the drive of the drive roller 47, thereby conveying the paper P.

[0049] The drive roller 47 rotates (endlessly moves) the conveyor belt 46. The drive rollers 47 of the two belt units 41 are connected to each other by a shaft 49.

[0050] The driven roller 48 supports the conveyor belt 46 together with the drive roller 47. The driven roller 48 rotates following the rotation of the rotating conveyor belt 46. The driven rollers 48 of the two belt units 41 are connected to each other by a shaft 50.

[0051] The conveying motor 42 rotates the shaft 49 to rotate the drive roller 47 .

[0052] The chamber 43 forms a negative pressure chamber for generating an adhesive force in the belt holes 46a of the belt unit 41. The chamber 43 holds the belt unit 41 inside so that the conveying surface 46b of the conveyor belt 46 is exposed. A ventilation hole (not shown) is formed in the bottom plate of the chamber 43 at a portion where the conveyor belt 46 passes. Air is sucked into the chamber 43 through the belt holes 46a in the conveying surface 46b of the conveyor belt 46 and the ventilation hole of the chamber 43, generating an adhesive force in the belt holes 46a.

[0053] The suction fan 44 exhausts air from the chamber 43. When the suction fan 44 exhausts air from the chamber 43, air is sucked into the chamber 43 from outside the chamber 43 through the belt holes 46a in the conveying surface 46b of the conveyor belt 46 and the ventilation holes in the chamber 43. The suction fan 44 is disposed above the chamber 43.

[0054] Upper limit sensor 12 monitors the downstream (right) edge of paper P stacked on paper feed tray 2. Upper limit sensor 12 is located downstream of paper feed tray 2 at a height position where it can detect floating paper P in the floating area. The floating area is an area in the vertical direction where main floating mechanism 8 and side air units 10A, 10B float paper P.

[0055] The control unit 13 controls the overall operation of the sheet feeding device 1. The control unit 13 includes a CPU, RAM, ROM, a hard disk, and the like.

[0056] The control unit 13 stores an adjustment table 51 shown in Fig. 8. The adjustment table 51 is a table that associates the paper type, paper size, and the degree of opening of the side floating air path 33.

[0057] The control unit 13 adjusts the air volume of the main floating fan 21, the main separation fan 26, and the side fan 31 according to the combination of paper type and paper size, and also adjusts the degree of opening of the side floating air path 33 by the opening / closing unit 38 by referring to the adjustment table 51.

[0058] The degree of opening of the side floating air path 33 in the adjustment table 51 is set so that the air volume of the side floating air blown out from the side floating air outlet 16 is an appropriate air volume when the air volume of the side fan 31 is set according to the combination of paper type and paper size.

[0059] The appropriate air volume for the side floating air is the air volume that prevents paper feeding problems (multiple feeding, empty feeding, etc.) caused by disturbances in the behavior of paper P floating up from the paper stack PT. For the same paper size, the thinner the paper type (the smaller the basis weight), the easier it is to float, so the appropriate air volume for the side floating air is smaller. For the same paper type, the smaller the paper size, the easier it is to float, so the appropriate air volume for the side floating air is smaller. However, in the example of Figure 8, for thick paper, the appropriate air volume is the same regardless of the paper size, and the degree of opening of the side floating air path 33 corresponding to thick paper is the same regardless of the paper size.

[0060] The degree of opening of the side floating air path 33 corresponding to each combination of paper type and paper size on the adjustment table 51 is set in advance based on, for example, experiments. In this embodiment, as described above, the side fan 31 can generate the appropriate air volume for each size of thick paper, but cannot adjust the air volume to a small value appropriate for thin paper and plain paper. For this reason, in this embodiment, as shown in Figure 8, the degree of opening of the side floating air path 33 is 0% for thick paper, and is not 0% for thin paper and plain paper.

[0061] Next, the operation of the paper feeder 1 will be described.

[0062] When a command to start paper feeding is issued, the control unit 13 refers to the adjustment table 51 and controls the opening / closing drive unit 39 to adjust the position of the opening / closing unit 38, thereby adjusting the degree of opening of the side floating air path 33, based on the paper type and size of the paper P loaded on the paper feed tray 2. Here, the paper type and paper size are input, for example, by the user operating an input unit (not shown).

[0063] Furthermore, the control unit 13 starts driving the main levitation fan 21, the main separation fan 26, the side fans 31 of the side air units 10A and 10B, and the suction fan 44. Here, the control unit 13 sets the airflow rates of the main levitation fan 21, the main separation fan 26, and the side fans 31 to airflow rates according to the paper type and paper size. Both shutters 22 and 35 are in the open state.

[0064] As a result, main floating air is blown out from main floating air outlet 23, main separation air is blown out from main separation air outlet 27, side floating air is blown out from side separation air outlet 16, and side separation air is blown out from side separation air outlet 17. In addition, an adhesive force is generated in belt holes 46a of belt unit 41.

[0065] Here, if the opening degree of the side floating air path 33 according to the paper type and paper size is not 0%, as shown in Figure 6, a portion of the air A1 from the side fan 31 flowing through the side floating air path 33, air A2, flows out from the opening 37, and the remaining air, side floating air A3, is blown out from the side floating air outlet 16. If the opening degree of the side floating air path 33 according to the paper type and paper size is 0%, as shown in Figure 7, the air from the side fan 31 flowing through the side floating air path 33 is blown out from the side floating air outlet 16 as side floating air A3.

[0066] The main floating air and the side floating air float multiple sheets of paper P in the floating area at the top of the stack of paper PT on the paper feed tray 2, and the topmost sheet P of the floated sheets P is adsorbed to the conveying surface 46b of the belt unit 41.

[0067] When the sheets P float up, side separation air is blown out from the side separation air outlets 17 near the side fence 6 above the uppermost sheet P. This side separation air flows along the rectifying member 18, creating a negative pressure between the rectifying member 18 and the uppermost sheet P. This draws the uppermost sheet P toward the rectifying member 18, and causes it to be sucked onto the rectifying member 18. As a result, side separation air flows between the uppermost sheet P and the second sheet P from the top.

[0068] On the other hand, on the main separation mechanism part 9 side, after the topmost sheet P is adsorbed onto the conveying surface 46b, the main separation air blown out from the main separation air outlet 27 flows upstream (to the left) along the topmost sheet P adsorbed onto the conveying surface 46b.

[0069] As a result, the main separation air, the side separation air from the front side, and the side separation air from the rear side collide with each other between the topmost sheet P and the second-highest sheet P, generating a positive pressure.

[0070] In this state, the control unit 13 controls the shutters 22 and 35 to close. This stops the main floating air from being blown out from the main floating air outlet 23 and the side floating air from the side floating air outlet 16. As a result, the positive pressure between the topmost sheet P and the second-highest sheet P pushes down the sheets P after the second from the top, separating the topmost sheet P from the sheets P after the second from the top. The second-highest sheets P fall onto the sheets P remaining on the sheet feed tray 2.

[0071] Thereafter, the control unit 13 controls the conveyance motor 42 to drive the belt unit 41 for a predetermined time, thereby conveying the uppermost sheet P attracted to the conveyance surface 46b.

[0072] Next, the control unit 13 opens the shutters 22 and 35 to feed the next sheets of paper P, and floats the uppermost sheets of paper P of the paper stack PT.

[0073] By repeating the above operation, the paper sheets P are sequentially fed from the paper feeder 1 to the destination printing device.

[0074] During this paper feeding operation, the control unit 13 controls the raising of the paper feed tray 2 in accordance with the decrease in the number of sheets P on the paper feed tray 2 due to the paper feeding. Specifically, for each sheet fed, the control unit 13 acquires the sensor value of the upper limit sensor 12 at the timing when the paper P is floating up. Then, if the acquired sensor value is less than a predetermined tracking threshold, the control unit 13 raises the paper feed tray 2 by an amount corresponding to the difference between the sensor value and the tracking threshold.

[0075] As described above, the paper feeder 1 is equipped with an adjustment mechanism 34 that adjusts the volume of the side floating air blown out from the side floating air outlet 16 by letting a portion of the air flow outside midway along the side floating air path 33. This allows the adjustment range of the volume of the side floating air blown out toward the paper stack PT to be wider than the adjustment range of the air volume of the side fan 31. As a result, it is possible to adjust the volume of the side floating air to an appropriate volume for a wide range of paper types and paper sizes.

[0076] Furthermore, in the paper feeder 1, the control unit 13 controls the adjustment mechanism 34 to adjust the volume of the side floating air blown out from the side floating air outlet 16 by adjusting the degree of opening of the side floating air path 33 based on the paper type and paper size. This allows the volume of the side floating air to be set to an appropriate volume according to the paper type and paper size, thereby reducing paper feeding problems (multiple feeding, empty feeding, etc.) caused by disturbances in the behavior of the paper P floating up from the paper stack PT.

[0077] In the above-described embodiment, the opening degree of the side floating air path 33 is adjusted by driving the opening / closing unit 38 with the opening / closing drive unit 39, but the opening degree of the side floating air path 33 may be manually operated. For example, the opening degree of the side floating air path 33 may be manually adjusted by operating the opening / closing unit 38 via a manual lever 61 as shown in FIG.

[0078] In the above embodiment, thin paper, regular paper, and thick paper are shown as paper types, but other types may also be included.

[0079] Furthermore, in the above-described embodiment, the side floating air and the side separation air are generated by a common source, the side fan 31, but the side floating air and the side separation air may be generated by different sources (fans).

[0080] In the above-described embodiment, the adjustment mechanism 34 is controlled to adjust the volume of the side floating air based on the paper type and paper size, but the adjustment mechanism 34 may also be controlled to adjust the volume of the side floating air based on either the paper type or the paper size. That is, the adjustment mechanism 34 may be controlled to adjust the volume of the side floating air based on at least one of the paper type and the paper size. The adjustment mechanism 34 may also be controlled to adjust the volume of the side floating air based on other factors.

[0081] Furthermore, in the above-described embodiment, a configuration in which the adjustment mechanism 34 is provided in the side floating air path 33 has been described, but an adjustment mechanism having a configuration similar to the adjustment mechanism 34 may also be provided in the side separation air path 36. Specifically, an adjustment mechanism 66 as shown in Fig. 10 may be provided in the side air unit 10. Note that Fig. 10 shows the adjustment mechanism 66 provided in the front side air unit 10A.

[0082] The adjustment mechanism 66 adjusts the volume of side separated air blown out from the side separated air outlet 17 by causing a portion of the air to flow out midway along the side separated air path 36. The adjustment mechanism 66 has the same configuration as the adjustment mechanism 34 described above, and includes an opening 67 formed midway along the side separated air path 36, an opening / closing unit 68 that opens and closes the opening 67, and an opening / closing drive unit 69 that drives the opening / closing unit 68.

[0083] Similar to the adjustment mechanism 34, the adjustment mechanism 66 can adjust the degree of opening of the side separation air path 36 by adjusting the position of the opening / closing part 38 in the vertical direction using the opening / closing drive part 39. The volume of side separation air A4 blown out from the side separation air outlet 17 is adjusted by adjusting the degree of opening of the side separation air path 36. The control part 13 controls the adjustment mechanism 66 to adjust the volume of side separation air based on the paper type and paper size.

[0084] By providing the adjustment mechanism 66 to the side air unit 10, the adjustment range of the air volume of the side separation air blown toward the paper stack PT can be expanded beyond the adjustment range of the air volume of the side fan 31. As a result, it is possible to adjust the air volume of the side separation air to an appropriate air volume for a wide range of paper types and paper sizes.

[0085] Furthermore, by controlling the adjustment mechanism 66 to adjust the volume of the side separation air based on the paper type and paper size, the volume of the side separation air can be set to an appropriate volume according to the paper type and paper size, thereby further reducing paper feeding problems (double feeding, empty feeding, etc.) caused by disturbances in the behavior of paper P that has risen from the paper stack PT.

[0086] The adjustment mechanism 66 may be controlled to adjust the volume of the side separation air based on the paper type or the paper size. That is, the adjustment mechanism 66 may be controlled to adjust the volume of the side separation air based on at least one of the paper type and the paper size. The adjustment mechanism 34 may also be controlled to adjust the volume of the side floating air based on other factors.

[0087] Furthermore, the adjustment mechanism 34 for the side floating air path 33 may be omitted, and the adjustment mechanism 66 may be provided for the side separation air path 36. In this case, too, the adjustment mechanism 66 can be controlled to adjust the volume of the side separation air based on at least one of the paper type and the paper size.

[0088] Furthermore, in the above-described embodiment, a paper feeder that feeds paper has been described, but the present invention can also be applied to a device that feeds sheets other than paper.

[0089] The present invention is not limited to the above-described embodiments, and the components can be modified and embodied in practice without departing from the spirit of the invention. Furthermore, various inventions can be created by appropriately combining multiple components disclosed in the above-described embodiments. For example, some components may be omitted from all the components shown in the embodiments.

[0090] [Note] The present application discloses the following inventions.

[0091] (Appendix 1) an air outlet that blows air toward the sheet stack from a side of the sheet stack; an air path through which air flows toward the air outlet; an adjustment mechanism that adjusts the volume of air blown out from the air outlet by letting a portion of the air out to the outside midway through the air path; A sheet feeding device comprising:

[0092] (Appendix 2) 2. The sheet feeding device according to claim 1, wherein the adjustment mechanism adjusts the volume of air blown out from the air outlet based on at least one of the type and size of the sheet.

[0093] (Appendix 3) a floating air outlet that blows out air to float the sheets of the sheet stack; a separation air outlet that is the outlet for blowing out air to separate the top sheet from the second and subsequent sheets from the top of the sheets floated from the sheet stack; a floating air path through which air flows toward the floating air outlet; a separation air path through which air flows toward the separation air outlet, 3. The sheet supplying device according to claim 1, wherein the adjustment mechanism is provided in at least one of the floating air path and the separating air path. [Explanation of symbols]

[0094] 1 Paper feeder 2 Paper feed tray 3 Lifting motor 4 Paper feed guide plate 5 Sabaki Gate 6,6A,6B Side fence 7 End Fence 8 Main levitation mechanism 9 Main separation mechanism 10, 10A, 10B Side air unit 11 Conveyor 12 Upper limit sensor 13 Control Unit 16 Side floating air outlet 17 Side separated air outlet 31 Side fan 32 Common side air path 33 Side floating air path 34,66 Adjustment mechanism 35 Shutter 36 Side separation air path 37,67 Opening 38,68 Opening and closing section 39,69 Opening and closing drive unit 51 Adjustment table P paper PT paper stack

Claims

1. an air outlet that blows air toward the sheet stack from a side of the sheet stack; an air path through which air flows toward the air outlet; an adjustment mechanism that adjusts the volume of air blown out from the air outlet by letting a portion of the air out to the outside midway through the air path, The sheet feeding device, wherein the adjustment mechanism adjusts the volume of air blown out from the air outlet based on the size of the sheet.

2. a floating air outlet that blows out air to float the sheets of the sheet stack; a separation air outlet that is the outlet for blowing out air to separate the top sheet from the second and subsequent sheets among the sheets floated from the sheet stack; a floating air path through which air flows toward the floating air outlet; a separation air path through which air flows toward the separation air outlet, 2. The sheet feeding device according to claim 1, wherein the adjustment mechanism is provided in at least one of the floating air path and the separating air path.

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