JP4158631B2 - Paper feeding device and paper feeding method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a paper feeding device used in a copying machine, a printer, a printing machine, and the like, and in particular, various paper-type papers including OHP paper and paper that has been pressed are reliably separated and sent out one by one. The present invention relates to a paper feeding device capable of performing the above.
[0002]
[Prior art]
2. Description of the Related Art A copying machine, a printer, or a printing machine is provided with a paper feeding device that feeds a plurality of laminated copy papers one by one with a paper feeding roller or the like. In such a sheet feeding device, if a large number of sheets are sent out at a time, a paper jam may occur. Further, if the feeding force is small, misfeeding is likely to occur. Therefore, the device which can send out one sheet reliably is made. That is, misfeeds are prevented by reliably feeding the uppermost sheet of the stacked sheets by increasing the coefficient of friction between the sheet feeding roller and the sheet. Further, in order to prevent two or more sheets from being fed, only the uppermost sheet is fed by pushing back the second and subsequent sheets by rolling with a rolling roller, padding or nail.
[0003]
This method is effective as long as only ordinary copy paper is used. However, recently, the use of copying machines and printers has expanded, and various types of paper such as OHP paper and embossed paper have been used. Among these sheets, there is a strong adhesion between sheets when stacked, and it may be difficult to reliably prevent a large number of sheets from being fed by the above-described paper feeding device. In recent years, so-called coated paper, such as glossy art paper or coated paper, has been used to provide high-quality color images. In addition to its high power, the weight of the paper itself is larger than that of normal copy paper, and many sheets and misfeeds are likely to occur.
[0004]
Therefore, by continuously blowing air to the side of the paper stacked in the paper feed tray, and setting the optimal value for the air blowing position and its strength according to the type of paper, A sheet feeding device that solves the problem that overlapping sheets remain in close contact with each other due to the positional relationship with the blower opening and reduces double feeding and sheet feeding errors is known (for example, Patent Document 1).
[0005]
Further, in the paper feeding device that feeds air to the stacked sheets from the side in the feeding direction, a blowing port that feeds air from the side in the feeding direction to the top of the laminated paper is provided, and the position of the blowing port in the feeding direction By providing a levitation suppressing member for suppressing the amount of paper floating between the position of the paper feed roller so as to be separated from the upper surface of the paper, the paper is reliably separated regardless of the size of the paper, There is also known a paper feeding device that can stably feed one sheet at a time and can stably measure the upper surface height of stacked sheets without being affected by the air that is fed in (for example, Patent Document 2). ).
[0006]
FIG. 5 is a view for explaining an example of a conventional paper feeding device. Air sent from a small fan (not shown) on the side portion restricting member 104 is near the upper end of the side portion restricting member 104. Wind is blown sideways on several sheets at the top of the stacked sheets 100 from the blower opening 122 opened at the top. Air blows through the gap between the sheets from one side of the upper several sheets 100b of the sheet and blows to the other side. Thus, the upper several sheets 100b are separated one by one. The paper feed roller can take out only the uppermost paper 100a from the paper 100 thus separated.
[0007]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-349165
[Patent Document 2]
Japanese Patent Laid-Open No. 2003-63675
[Problems to be solved by the invention]
However, in the paper feeding devices described in Patent Document 1 and Patent Document 2, when air is sent from the air blowing port 122 to float the stacked paper, between the upper end of the paper 100 and the air blowing port 122, that is, one The problem is that most of the air is discharged from the opening of the blower opening 122 at the top of the uppermost sheet 100a, and the wind is blown only on the upper surface of the stacked sheets, so that the sheets cannot be lifted themselves. May occur. In particular, this problem was conspicuous when large coated papers having high adhesion and weight were laminated.
[0010]
In addition, in order to reduce the amount of air discharged to the upper surface of the paper, when the gap between the uppermost paper 100a and the upper end of the air outlet 122 is reduced, the paper can be levitated. When the uppermost sheet 100a is lifted to a position higher than the upper end of the air outlet 122, as shown in FIG. 5, a plurality of sheets are floated together in close contact with each other, and wind is generated in the gaps between the sheets. There was a problem that the sheets could not be separated for each sheet.
[0011]
Furthermore, if the exhaust amount of the fan 120 is increased in order to increase the amount of air sent from the blower port 122, problems such as an increase in the size of the device, an increase in noise, and the rising of dust due to the discharged air may occur. There is sex.
[0012]
Therefore, the present invention is to solve the above problems, and in a paper feeding device that sends air between stacked paper, the configuration is simple and small, and the paper is reliably separated regardless of the type of paper. An object of the present invention is to provide a sheet feeding device that can stably feed one sheet at a time.
[0013]
[Means for Solving the Problems]
The object of the present invention can be achieved by the following constitution.
[0014]
(1) In a paper feeding device that provides an air blowing port for sending air between the stacked sheets, and sends out the sheets floated by the air sent from the air blowing port one by one,
A contact member that contacts the top surface of the floated paper;
Follow-up means for bringing the abutting member into contact with the uppermost surface of the paper that has floated following the levitation of the paper;
A shielding member that regulates air feeding by the air blowing port by shielding the air blowing port;
The shielding member is connected to the abutting member, and changes a relative position with respect to the air blowing port in conjunction with the tracking of the abutting member to the uppermost surface of the sheet. apparatus.
[0015]
(2) having a sheet end regulating member that regulates the end position of the stacked sheets, the fan opening in the sheet end regulating member, a fan using the blow outlet as an air outlet, and the contact The sheet feeding device according to (1), wherein a contact member, the following unit, and the shielding member are provided.
[0016]
(3) The sheet feeding device according to (1) or (2), wherein the contact member includes a roller that is rotatable along a sheet feeding direction of the sheet feeding device.
[0017]
(4) The contact member is displaceable between a contact position that contacts the uppermost surface of the stacked sheets and an open position that opens the upper surface of the stacked sheets (1). To (3).
[0018]
(5) The sheet feeding device is configured to send a sheet fed one by one with the air floated by the air sent from the air blowing port, and to normal paper feeding that feeds the paper one by one without sending air from the air blowing port. Switch between modes,
During the blow air feeding mode operation, the contact member is displaced from an open position where the upper surface of the stacked sheets is opened to a contact position where the upper surface of the stacked sheets is contacted. The sheet feeding device according to (4).
[0019]
(6) In a paper feeding method in which an air blowing port for sending air is provided between the stacked sheets, and the uppermost sheet floated by the air sent from the air blowing port is sent one by one.
By shielding the air blowing port, a shielding member for restricting air feeding by the air blowing port is provided,
Following the levitation of the uppermost paper, the shielding member is moved so that the shielding member and the uppermost surface of the levitated uppermost paper maintain a certain positional relationship. Paper feeding method to be used.
[0020]
According to the invention of (1), the shielding member moves in conjunction with the abutting member while suppressing excessive levitation of the paper by the abutting member that follows the uppermost surface of the paper that is levitated by the air sent from the blower opening. By doing so, the position of the air blowing port can always maintain a certain positional relationship with the uppermost surface of the sheet, so that the wind passes through the gaps between the sheets, and separation of each sheet can be performed reliably. In addition, the air sent from the blower port spreads over almost the entire surface of the paper, and a gap is formed between the papers, so that the papers are separated and the papers are easily sent out one by one.
[0021]
According to the invention of (2), since the blower opening and the shielding member are provided in the paper end regulating member, even if the size of the stacked paper is changed, the paper end regulating member is caused to follow the paper. In this case, the air blower opening whose opening is adjusted by the shielding member is always installed at a certain distance from the paper at the position where the wind passes through the gaps between the papers, so that the air sent from the air blower escapes. Therefore, separation of each sheet can be performed reliably without being limited by the size of the sheet.
[0022]
According to the invention of (3), since the roller that is rotatable along the paper feeding direction of the paper feeding device is provided as the contact member, the contact member does not become a frictional resistance during paper conveyance, and a good paper Transport is possible.
[0023]
According to the invention of (4), since the contact member can be moved to the open position, the contact member does not get in the way even when the paper is replenished.
[0024]
According to the invention of (5), by automatically abutting and releasing the abutting member, the user's operation is not bothered and an operation error by the user can be avoided. Further, in the normal paper feeding mode in which air is not sent from the air blowing port, it is possible to prevent a conveyance failure due to the frictional force generated by contacting the contact member.
[0025]
According to the invention of (6), the upper end of the opening formed by the air blowing port and the shielding member is always moved by the movement of the shielding member following the upper surface of the sheet floated by the air sent from the air blowing port. Since a certain positional relationship with the uppermost sheet can be maintained, the wind passes through the gaps between the sheets, and separation of each sheet can be performed reliably.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
An example of an embodiment of the present invention will be described with reference to the drawings. The description in this column does not limit the technical scope of the claims or the meaning of terms.
[0027]
FIG. 1 is a perspective view of a paper feeding apparatus according to the present invention.
FIG. 1A is a perspective view showing a main part in a state where a cover of the paper feeding device is removed, and FIG. 1B shows a paper upper surface height detection unit (not shown in FIG. 1A). FIG. FIG. 2 is a longitudinal sectional view of the main part of the paper feeding device.
[0028]
In FIG. 1A, the stacked sheets 100 are placed on a sheet placing table (not shown) and supported by a lifting mechanism (not shown) so as to be raised and lowered. The side regulating member 104, which is a paper edge regulating member, is movable in the direction crossing the feeding direction (Y direction in the figure) of the paper 100, in the present embodiment, in the width direction (X direction in the figure). The both sides of the paper 100 are regulated by contacting both sides of the paper 100. The trailing edge regulating member 105 is movable in the conveyance direction (Y direction in the figure) of the paper 100, regulates the position of the trailing edge of the paper 100 in the feeding direction, and can also function as a paper edge regulating member. At the leading edge of the paper 100 in the feed direction, there is a paper feed roller 106 that presses the top paper 100a with an appropriate force.
[0029]
When the paper feed roller 106 rotates in the direction of the arrow a, the uppermost paper 100a advances in the direction of the arrow b and contacts the lower separation roller 107a, which is a paper separation means, adjacent to the outlet side of the paper feed roller 106. Touch. When double feed occurs, the second and lower sheets below are pushed back by the separation lower roller 107a rotating in the same direction as the arrow a, and only the uppermost sheet is conveyed by the separation upper roller 107b and the pre-registration roller 109. Then, it is sent to the image forming unit.
[0030]
In FIG. 1B, a sheet upper surface sensor 110 is provided to detect the height of the uppermost surface of the stacked sheets. The paper upper surface sensor 110 includes an oval and arc-shaped hole 112 in which the shaft 108 of the paper feed roller 106 can be loosely fitted, a rotation shaft 114 that pivotally supports the detection unit 112, and a detection. The light shielding plate 116 is fixed to the portion 112, and the photocoupler 118 is provided so as to sandwich the tip portion of the light shielding plate 116. The separation upper roller 107 b is rotated by the power of the rotating shaft 114. In the detection unit 112 and the light shielding plate 116, the detection unit 112 is heavier, and the detection unit 112 always keeps a light contact with the upper surface of the paper 100. When the position of the upper surface of the paper 100 is lowered, the detection unit 112 is lowered at the same time, and the tip of the light shielding plate 116 is swung to be detached from the photocoupler 118. Detect that the position has dropped. Then, an elevating device (not shown) is operated to raise the paper 100 to a position where the tip of the light shielding plate 116 blocks the light of the photocoupler 118. As described above, the upper surface of the paper 100, that is, the position of the uppermost paper 100a is always kept at the same height. The sheet upper surface sensor 110 is not limited to the one having the configuration shown in the figure, and may be any sensor as long as the sheet upper surface position can be detected.
[0031]
A small fan 120 is attached to each side restricting member 104 so as to send out air to the blower opening 122 as a paper-making means. The air sent upward from the fan 120 changes its direction by 90 ° by a fan mounting plate (not shown) and is blown out from the blower opening 122 almost horizontally. The air blowing port 122 is opened near the upper end of the side portion regulating member 104, and has a lattice-like opening so that foreign matter may not enter and the fan 120 may be damaged. The width of the air outlet 122 is the same as the width of the air outlet of the fan 120. A positional relationship in which the uppermost sheet 100a is located at substantially the center of the upper and lower ends of the air outlet 122 is desirable. Since the fan 120 is attached to the side restriction member 104, even when the size of the paper 100 is changed, the fan 120 can be moved together in the X direction in the drawing by moving the side restriction member 104.
[0032]
In addition, a shutter mechanism 200 is mounted on the upper side of the side regulating member 104 so as to follow a height of the upper surface of the floated paper and shield a part of the air blowing port 122 to change the opening. . Details of the shutter mechanism 200 will be described later.
[0033]
When the fan 120 rotates, air is sent from the air blowing port 122 and wind is blown on several sheets at the top of the stacked sheets 100. The air passes through the gap between the sheets from one side of the upper several sheets 100b and blows to the other side. As a result, the adhesion between the sheets is reduced. As a result, the upper several sheets 100b of the paper are separated and separated one by one. The paper feed roller 106 takes out only the uppermost paper 100a from the paper 100 thus wound and feeds it to the image forming unit.
[0034]
In this embodiment, the fan 120, the air blowing port 122, and the shutter mechanism 200 are provided on both sides in the paper 100 feed direction, but may be provided on only one side. Further, as another embodiment of the sheet end regulating member, the same effect can be obtained by providing the rear end regulating member 105 with the fan 120, the air blowing port 120, and the shutter mechanism 200.
[0035]
Further, as shown in FIG. 2, a cover 126 is attached to the sheet feeding device. The cover 126 can be rotated with respect to the main body by a hinge 128 at the tip.
[0036]
A shutter mechanism 200 according to the present invention will be described below with reference to FIG.
[0037]
FIG. 3A is a front view of the shutter mechanism 200, and FIG. 3B is a diagram for explaining the operation of the shutter mechanism 200. The shutter mechanism 200 according to the present invention includes contact rollers 201a and 201b, which are contact members, a shielding member 202, arms 204a and 204b, a swing base 205, and a mounting base 207. The shutter mechanism 200 is fixed to the upper surface of the side portion regulating member 104 via the attachment base 207.
[0038]
The contact rollers 201a and 201b, which are contact members, are composed of rollers that are rotatable in the paper feeding direction (clockwise on the paper surface) of the paper feeding device, and the lower surfaces of the contact rollers 201a and 201b It is in contact with the upper surface of 100a. Thus, the resistance in the paper transport direction (Y direction in the figure) is minimized, and even if the contact rollers 201a and 201b are in contact with the uppermost paper 100a, a good paper by the paper supply roller 106 in FIG. Transport is possible.
[0039]
The contact rollers 201a and 201b are pivotally attached to the shielding member 202 by pins 203a and 203b, respectively, so that the lower part of the roller slightly protrudes from the bottom surface of the shielding member. The relative positional relationship with the upper surface of the uppermost sheet 100a is kept constant. The outer diameters of the contact rollers 201a and 201b are 10 mm to 30 mm, and the lower part of the rollers is attached so as to protrude 1 mm to 4 mm from the bottom surface of the shielding member. In place of the roller, a member having a sliding surface covered with a low friction material such as a fluororesin may be brought into contact with the uppermost sheet 100a.
[0040]
The shielding member 202, the arms 204a and 204b, and the swing base portion 205 constitute a parallelogram link mechanism, and function as a follow-up means by the link mechanism. That is, with the shielding member 202 supporting the contact rollers 201a and 201b as the base of the parallelogram, the arms 204a and 204b are pivotally mounted by the pins 203a and 203b, respectively, and the swing base 205 is connected to the parallelogram. As the upper side, arms 204a and 204b are pivotally attached to pins 206a and 206b, respectively. The arms 204a and 204b swing around the fixed swing base 205, so that the shielding member 202 can be displaced up and down while maintaining a state substantially parallel to the upper surface of the top sheet 100a. Thus, even if the position of the uppermost surface of the paper that is in contact with the contact rollers 201a and 201b is displaced, it can follow this. In the present embodiment, the parallelogram link mechanism is used, but there is no particular limitation as long as the contact member can follow the uppermost surface of the sheet to be displaced, and for example, a support mechanism using a solenoid or a coil spring may be used. Is possible.
[0041]
The shielding member 202 includes a connecting portion that is connected to the contact rollers 201a and 201b and the arms 204a and 204b, and a shielding portion 202a that faces the air blowing port 122, and these are configured as an integral unit through the bottom. . The shielding part 202a is close so as to cover a part of the air blowing port 122, and the area and the position where air is sent out from the air blowing port 122 are limited. It is preferable that the upper end of the shielding member 202a shields the upper end portion of the air blowing port 122 even when the shielding member 202 reaches the lowest point. The left and right ends of the shielding portion 202a have the shielding member 202 at the lowest point. It is preferable that a part of the width direction (W area in the drawing) of the air outlet 122 is always shielded while moving from the uppermost point to the uppermost point, and more preferably, all the width direction of the air outlet 122 is always shielded. Is.
[0042]
Moreover, in order to improve the shielding effect of the air sent from the ventilation port 122, the shielding part 202a has stuck the plastic sheet on the surface which opposes the ventilation port 122. It is also possible to attach an airtight holding member like this or to attach a non-woven fabric instead of a plastic sheet.
[0043]
A stopper (not shown) is provided at the lower limit displacement position of the shielding member 202. This lower limit position is slightly higher than the uppermost surface of the paper in the normal paper feeding mode, and is located below the contact rollers 201a and 201b. The interval is 0.5 to 4 mm. Thereby, in the normal paper feed mode, the contact rollers 201a and 201b, which are contact members, come into contact with the paper and become unnecessary resistance, thereby preventing a paper feed failure.
[0044]
The swing base portion 205 is pivotally attached to the mounting base portion 207 by pins 208a and 208b. The swing base portion 205 includes contact rollers 201a and 201b serving as contact members, a shielding member 202, and arms 204a and 204b serving as followers. The shutter mechanism 200 is supported. The swing base 205 is pivotally attached to the mounting base 207 so that when the paper is replenished, the swing base 205 swings around the pins 208a and 208b, and the contact rollers 201a and 201b, which are contact members, are shielded. The shutter mechanism 200 including the member 202 and the arms 204a and 204b as follow-up means can be displaced to an open position where the top surface of the paper is opened.
[0045]
Next, the operation of the shutter mechanism 200 will be described.
The air sent out from the blower port 122 is obstructed by the shielding part 202a and blown onto the side surfaces of the upper several sheets 100b of the stacked sheets 100. Air blows through the gaps between the sheets from one side of the upper several sheets 100b. As a result, the upper several sheets 100b float, and the shielding member 202 connected to the contact rollers 201a and 201b that contact the upper surface of the uppermost sheet 100a is formed of arms 204a and 204b and a swing base 205. Due to the action of the quadrilateral link mechanism, it moves upward while following the upper surface of the uppermost sheet 100a to be levitated. Thus, the distance D between the lower end of the shielding portion 202a attached to the shielding member 202 and the upper surface of the uppermost sheet 100a, that is, the uppermost surface of the sheet, is always kept constant regardless of the amount of floating of the sheet. The blowing of air from 122 to the side surface of the upper several sheets 100b of the sheet 100 becomes stable. As a result, the upper several sheets 100b of the paper are separated and separated one by one. The paper feed roller 106 can reliably feed only the uppermost paper 100a from the paper 100 thus wound to the image forming unit.
[0046]
FIG. 4 is a diagram illustrating a state in which the shutter mechanism 200 is displaced to the open position. The bottom surface of the shielding member 202 faces upward, and the arms 202a and 202b are displaced to positions where they come into contact with the shielding member 202 and the swing base 205. When the cover 126 shown in FIG. 2 is in a closed state, the shutter mechanism 200 is in an operating position where the air outlet 122 is shielded. When the cover 126 is opened, the shutter mechanism 200 moves together with the cover 126 to an open position away from the upper surface of the paper 100. As a result, the cover 126 can be opened and the paper 100 can be replenished.
[0047]
The sheet feeding device of the present invention includes a blowing sheet feeding mode in which sheets floated by air sent from the blowing port 122 are sent one by one, and a normal feeding mode in which sheets are fed one by one without feeding air from the blowing port 122. It can be switched to. This will be described below.
[0048]
Switching between the blowing paper feeding mode and the normal paper feeding mode is performed by using an operation unit (not shown) of the image forming apparatus having the paper feeding device of the present invention or a sheet selected by a computer that can communicate with the image forming apparatus. This is performed by a CPU (not shown) of the image forming apparatus based on the type. For example, when the selected paper type is OHP paper, coated paper, or embossed paper, the air supply mode is set. At this time, the shutter mechanism 200 causes the contact rollers 201a and 201b to float by the air sent from the air outlet 122. The operation position is in contact with the upper surface of the uppermost sheet 100a. If the selected paper type is other than the above, the normal paper feed mode is set and the fan 120 is disabled.
[0049]
A stopper (not shown) is provided at the lower limit displacement position of the shielding member 202, and this lower limit position is slightly higher than the uppermost surface of the sheet in the normal sheet feeding mode. As a result, in the normal paper feeding mode, the frictional resistance by the contact rollers 201a and 201b is reduced, so that the conveyance failure can be avoided and the conveyance load on the paper feeding roller 106 is reduced. Combined with 120 non-operations, power consumption can be greatly reduced.
[0050]
As another mode of the normal paper feeding mode, the shutter mechanism 200 is displaced to the open position as shown in FIG. 4 by a stepping motor (not shown). Also in this case, the contact by the contact rollers 201a and 201b is surely avoided, so that the frictional resistance is reduced, so that the conveyance failure can be avoided, and in addition, when a paper jam occurs, the shutter is released. It is possible to avoid the mechanism 200 or the paper S from being damaged.
[0051]
【The invention's effect】
As described above, according to the present invention, in the paper feeding device that sends air between the stacked papers, the configuration is simple, the paper is reliably separated regardless of the type of paper, and 1 is stably provided. It became possible to send out one by one.
[Brief description of the drawings]
FIG. 1 is a perspective view illustrating a main part in a state where a cover is removed in a paper feeding device according to the present invention.
FIG. 2 is a longitudinal sectional view of a main part of a paper feeding device.
FIGS. 3A and 3B are a front view and a side view of a main part of a shutter mechanism. FIGS.
FIG. 4 is a perspective view of a main part of a shutter mechanism.
FIG. 5 is a diagram illustrating an operation of a conventional paper feeding device.
[Explanation of symbols]
100 Paper 100a Uppermost paper 104 Side restriction member 106 Paper feed roller 110 Paper upper surface sensor 120 Fan 122 Blower port 200 Shutter mechanism 201a, 201b Contact roller 202 Shield member 204a, 204b Arm 205 Swing base 207 Mounting base

Claims (6)

In a paper feeding device that provides an air blowing port for sending air between the stacked papers, and sends out the sheets floated by the air sent from the air blowing port one by one,
A contact member that contacts the top surface of the floated paper;
Follow-up means for bringing the abutting member into contact with the uppermost surface of the paper that has floated following the levitation of the paper;
A shielding member that regulates air feeding by the air blowing port by shielding the air blowing port;
The shielding member is connected to the abutting member, and changes a relative position with respect to the air blowing port in conjunction with the tracking of the abutting member to the uppermost surface of the sheet. apparatus. A paper end restricting member for restricting the end position of the stacked paper, the fan at the paper end restricting member, a fan having the air outlet as an air outlet, and the contact member The sheet feeding device according to claim 1, further comprising: a follow-up unit; and the shielding member. The sheet feeding device according to claim 1, wherein the contact member includes a roller that is rotatable along a sheet feeding direction of the sheet feeding device. 4. The contact member according to claim 1, wherein the contact member is displaceable between a contact position that contacts the uppermost surface of the stacked sheets and an open position that opens an upper surface of the stacked sheets. The sheet feeding device according to any one of the above. The paper feeding device has a blow paper feeding mode for sending out sheets one sheet at a time by the air sent from the blower opening, and a normal paper feeding mode for sending sheets one by one without sending air from the blower opening. The contact member can be switched from an open position where the top surface of the stacked sheets is opened to a contact position where the top surface of the stacked sheets is contacted during the blowing paper feeding mode operation. The sheet feeding device according to claim 4, wherein the sheet feeding device is displaced. In a paper feeding method in which an air blowing port for sending air is provided between stacked sheets, and the uppermost paper floated by the air sent from the air blowing port is sent one by one,
By shielding the air blowing port, a shielding member for restricting air feeding by the air blowing port is provided,
Following the levitation of the uppermost paper, the shielding member is moved so that the shielding member and the uppermost surface of the levitated uppermost paper maintain a certain positional relationship. Paper feeding method to be used.

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