JP2004189432A - Paper feeding device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air-blow type paper feeding device capable of suppressing noise such as wind noise, and performing consistent paper feed operation considering energy saving. <P>SOLUTION: The paper feeding device comprises a separation means which feeds stacked paper sheets by a feed means and separates the paper sheets one by one by a separation roller, and an air blow port to feed air to an upper side surface of the stacked paper sheets in addition to a carrying means to carry the paper sheets, and a paper sheet shuffling means to pass air between first and second paper sheets from the top. In addition, a control means to control the paper sheet shuffling means is provided, so that the passing time from the start of the paper sheet feed operation to the detection of a paper sheet tip by a paper sheet tip detection sensor is measured, and air blow is started from the air blow port when the passing time is not less than the first reference time. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a paper feeding device used for a copier, a printer, a printing machine, and the like, and more particularly, to a variety of paper types including OHP sheets, coated paper, crimped paper, etc. The present invention relates to a sheet feeding device that can be fed separately.
[0002]
[Prior art]
2. Description of the Related Art A copying machine, a printer, or a printing machine is provided with a paper feed roller that feeds a large number of stacked sheets one by one using a paper feed roller or the like. In such a sheet feeding device, if a large number of sheets are fed at a time (double feed), a paper jam is caused. In addition, if the feeding force is reduced due to slippage of the paper feed roller due to paper dust or the like, misfeeding is likely to occur. For this reason, a device has been devised so that the sheets can be sent out one by one. In other words, misfeeding is prevented by increasing the coefficient of friction between the paper feed roller and the paper and reliably feeding the top one of the stacked papers. Further, in the case of double feed or the like, only the top sheet is fed out, and the lower two sheets are pushed back.
[0003]
This method is an effective method as long as only a normal copying machine is used. However, recently, the use of copiers and printers has expanded, and various types of papers have been used, including OHP sheets, coated papers, crimped papers, and the like. Among these sheets, when the sheets are stacked, the adhesion between the sheets is strong, and the uppermost sheet and the following sheets are in close contact with each other. In some cases, it is difficult to reliably prevent multi-sheet feeding. In addition, paper dust from the paper also reduces the frictional force with the roller, creating a cause of weakening the conveying force of the feed roller.
[0004]
Therefore, an air outlet is provided on the side in the feed direction of the stacked sheets, and air is blown from the air outlet toward a plurality of upper sheets of the stacked sheets, and air is passed between the sheets. A separation method has been proposed (for example, see Patent Document 1).
[0005]
[Patent Document 1]
JP-A-11-5643 (column 10, lines 1 to 7)
[0006]
[Problems to be solved by the invention]
According to the conventional method, when the copy (printing) operation is started, if the paper type that satisfies the operation conditions is determined in advance by the information of the type of the set paper, it is necessary to operate the air blowing operation switch according to the judgment of the operator or the like. It is decided whether or not. However, even if the feeding is performed without any problem and the spraying is not necessary, once the spraying operation is started, the operation is continued, so that the mechanical operation noise due to the wind noise and the sound of the paper increases, and A problem arises in that the power of the pump, fan, etc., which is the blowing operation source, is wasted.
[0007]
Further, in the case of paper having a large amount of paper dust, even if it is not necessary to blow air in the initial state, there is also a problem that the feeding roller slips due to the paper dust as the paper is passed, the conveyance force is reduced, and a misfeed occurs. . Alternatively, even when the roller surface is worn, the conveying force of the feed roller is similarly reduced, causing a misfeed.
[0008]
The present invention automatically determines the necessity of air blowing operation based on the paper feeding state, starts blowing only when necessary, suppresses noise such as wind noise, paper sound as much as possible, and wastes power consumption. It is an object of the present invention to provide a sheet feeding device in which a stable sheet feeding operation is performed.
[0009]
[Means for Solving the Problems]
The above object is achieved by the following configuration.
[0010]
The paper stacked on the paper feed tray is sent out by the feeding means, and the separating means for separating the sheets one by one by a separation roller and the transporting means for transporting the separated paper are added to the upper side surface of the loaded paper. In a paper feeding device having a blowing port for feeding air and a paper separating means for passing air between the first and second upper sheets, a paper leading edge detection sensor detects a leading edge of the paper after a paper feeding operation is started. The apparatus further comprises control means for measuring a passage time until the detection, and controlling the sheet separating means so as to start blowing air from the air blowing port when the passage time is equal to or longer than a first reference time. Paper feeder.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
An example of an embodiment of the present invention will be described with reference to the drawings. Note that the description in this column does not limit the technical scope of the claims and the meaning of terms.
[0012]
FIG. 1 is a perspective view of the sheet feeding device of the present invention.
FIG. 1A is a perspective view showing a main part of the paper feeding device with a cover removed, and FIG. 1B shows a paper upper surface height detection unit not shown in FIG. 1A. FIG. 2 is a longitudinal sectional view of a main part of the sheet feeding device, and FIG. 3 is a top view of the main part of FIG.
[0013]
In FIG. 1A, the stacked paper 100 is placed on a plate 102 (see FIG. 3) and supported by a mechanism (not shown) so as to be able to move up and down. The side regulating member 104 such as a side plate is movable in a direction intersecting with the feeding direction of the paper 100, that is, in the width direction in the present embodiment. Restricts both sides. The rear end regulating member 105 (see FIG. 3) is movable in the length direction of the paper 100 and regulates the position of the rear end of the paper 100 in the feeding direction. A feed roller 106 is provided at the leading end of the sheet 100 in the feeding direction, and presses the uppermost sheet 100a with an appropriate force.
[0014]
When the paper feed roller 106 rotates in the direction of arrow a, the uppermost sheet 100a advances in the direction of arrow b, and it may be a sheet separating unit adjacent to the exit side of the paper feed roller 106. When the double feed occurs, the second and subsequent lower sheets are pushed back by the separating lower roller 107a rotating in the same direction as the arrow a, and only the uppermost sheet is fed to the image forming unit.
[0015]
In FIG. 1B, a paper upper surface sensor 110 is provided to detect the height of the uppermost surface of the stacked paper. The paper upper surface sensor 110 includes a detection unit 112 having an elliptical and arc-shaped hole into which the shaft 108 of the paper feed roller 106 can be loosely fitted, a rotation shaft 114 that rotatably supports the detection unit 112, The light shielding plate 116 includes a light shielding plate 116 fixed to the portion 112 and a photocoupler 118 provided so as to sandwich the tip of the light shielding plate 116. The upper separation roller 107b is rotated by the power of the rotating shaft 114. The detection unit 112 is heavier between the detection unit 112 and the light shielding plate 116, so that the detection unit 112 is always in light contact with the upper surface of the sheet 100. When the position of the upper surface of the sheet 100 is lowered, the detecting unit 112 is lowered, and the tip of the light-shielding plate 116 is raised and detached from the photocoupler 118. Therefore, the light receiving unit detects light, and the position of the top sheet 100a is detected. To detect that the temperature has dropped. Then, an elevating device (not shown) operates to raise the sheet 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 sheet 100, that is, the position of the top sheet 100a is always kept at the same height. The paper upper surface sensor 110 is not limited to the one shown in the drawing, and may be any sensor as long as it can detect the paper upper surface position.
[0016]
A small separating fan 120 is attached to the side regulating member 104 upward as a sheet separating means. The air blown upward is turned 90 ° by a fan mounting plate (not shown), and is blown out from the air outlet 122 sideways. The air outlet 122 is open near the upper end of the side regulating member 104. The width of the blowing port 122 is the same as the width of the outlet of the loosening fan 120. It is desirable that the uppermost sheet 100a be located substantially at the center of the upper and lower ends of the air outlet 122. Since the loosening fan 120 is attached to the side regulating member 104, even if the size of the paper 100 is changed, by moving the side regulating member 104, the loosening fan 120 can move together.
[0017]
In the present embodiment, the separating fan 120 and the air outlet 122 are provided on both sides of the sheet 100, but may be provided on only one side.
[0018]
When the separating fan 120 is rotated, air is sent from the air blowing port 122, and the air is blown on several sheets above the stacked sheets 100. The air blows from one side of the upper several sheets 100b through the gap between the sheets to the other side. As a result, the adhesion between the sheets is reduced.
[0019]
Thus, the upper several sheets 100b of the sheet are separated one by one and separated. The paper feed roller 106 can take out only the uppermost paper 100a from the paper 100 thus sorted and send it in reliably. In order to prevent the upper several sheets 100b of the sheet 100 from rising, a floating suppression member 124 is provided. Since the floating restraint member 124 is provided not to be in close contact with the upper surface of the sheet 100 but to be floated by a predetermined gap, it is possible to reduce the resistance force when feeding the sheet 100a.
[0020]
Further, as shown in FIG. 2, a cover 126 is attached to the sheet feeding device. The cover 126 is rotatable with respect to the main body by a hinge 128 at the tip. When the cover 126 is closed, the levitating restraint member 124 is in the operating position for restraining the amount of floating of the sheet. When the cover 126 is opened, the levitation suppressing member 124 moves together with the cover 126 to a retracted position away from the position where the amount of levitation on the sheet 100 is suppressed. Thus, the cover 126 can be opened to replenish the paper 100.
[0021]
The above is the details of the hardware of the sheet feeding device according to the embodiment of the present invention. However, the present invention is different from the conventional method regarding the control of air blowing which is a soft surface.
[0022]
Conventionally, it is determined whether the operation of the air blowing operation switch is necessary by the judgment of the operator or the like, and the blowing mode is selected, whereas in the present invention, the necessity of the air blowing is recognized by the paper feeding state, It is characterized in that the air blowing operation is automatically started, and the paper is separated and the paper dust is diffused.
[0023]
Hereinafter, features of the present invention will be described. However, it is assumed that control relating to sheet feeding, air blowing, and the like is performed by a control unit C as a control unit.
[0024]
First, a passage time T from when the sheet is started to be fed (when the delivery clutch is turned on) to when the sheet reaches the leading end detection sensor 115 is measured by a timer of the control unit C, and the passage time T is determined as the jam detection time. less than T _MAX, the command and to blow the air to the air blowing port 122 from the control unit C if it becomes larger than the first reference time T _1, the loosening fan 120 is controlled (Note that the leading edge sensor 115 Is disposed between the separating roller 107 and the transport roller 109).
[0025]
Here, the first reference time T ₁ is a time obtained by adding a variation to an average value T _{AV of} times determined by collecting data of a plurality of passing times T and a passing time at the time of normal paper feeding. large, is set in a feedable maximum time (beyond which time the jam) T _{MA X} less time.
[0026]
Further, passing time T is greater than the second reference time T _2, in the first reference time T ₁ is less than the range, as well if it is measured continuously over a predetermined number of times, to the blowing port 122 An instruction is given to blow the wind, and the loosening fan 120 is controlled.
[0027]
Here, T ₂ the second reference time, the greater than the transit time of the normal feed, is set at the first reference time T ₁ is less than the range.
[0028]
The above-mentioned time is represented by the relationship of the passage time during normal paper feeding <the second reference time <the first reference time <the maximum time that paper can be passed.
[0029]
Also, in the case of a plurality of paper feeds, even when the variation width of the passage time T for each time becomes larger than a predetermined value, the control unit C instructs the blower 122 to blow air, and the loosening fan 120 Controlled.
[0030]
While the spraying operation is being performed, a display lamp indicating “spraying” is lit on the operation unit.
[0031]
In the present invention, the above-described control is applied only when the AUT (automatic) mode is selected. However, in the paper feeding apparatus according to the present embodiment, the ON mode and the OFF mode can be manually selected in addition to the AUT mode. is there.
[0032]
FIG. 4 is a diagram showing a part of an operation panel as an operation unit.
In the figure, reference numeral 200 denotes an operation panel, and reference numerals 201, 202, and 203 denote buttons for selecting an AUT (automatic) mode, an ON mode, and an OFF mode of the sheet separating means, and are instruction buttons to the control unit C. Reference numeral 204 denotes a display lamp which is turned on while the separating fan, which is the sheet separating means, is driven.
[0033]
In the present embodiment, the control method determined from the paper feeding state is applied only when the AUT (automatic) mode is selected. When the power of the apparatus is ON, the loosening fan is constantly rotating, and in the OFF mode, the rotation command is cut off. However, when the door is opened in the case of the paper jam processing, the loosening fan is considered to stop.
[0034]
In addition, various setting methods are conceivable for the period during which air is blown from the loosening fan 120 (the loosening fan driving time). For example, until the last sheet of the set number of copies has been ejected, or until the paper tray loaded with the target paper is empty, or The operation is continued until the use of the plate is switched or until the operator performs an operation (OFF mode selection) to stop the air supply at the operation unit.
[0035]
In the case of paper having a large amount of paper dust, the paper powder reduces the conveyance force of the paper feed roller 106 and the separating roller 107, causing the roller and the paper to slip, and the time to the leading edge detection sensor 115 becomes longer. Therefore, by blowing air, the first and second upper sheets can be separated from each other, and the paper dust can be removed, so that the conveying force can be increased, and misfeeding can be avoided.
[0036]
Next, the paper feed operation of the main claim of the present invention will be described with reference to a flowchart.
[0037]
FIG. 5 is a flowchart for explaining the flow of the sheet feeding operation.
1 and 5, at the same time as the image forming operation is started, the sending clutch (not shown) that engages with the shaft 108 of the sheet feeding roller 106 is turned on in step S11, and at the same time, the sending time measuring timer of the control unit C is set in step S12. When it is turned on, the sheet 100a is sent, reaches the leading edge detection sensor 115 via the separating roller 107, the sending time measuring timer is turned off in step S13, the time T is measured, and the leading end of the sheet 100a (See FIG. 2) of the transport roller 109. Here, if the passing time T> first reference time T ₁ is Yes in step S14, i.e., the pass time period T is the first reference time T ₁ for sliding the feed roller 108 to the separating roller 107 in step S14 If it becomes longer, in step S15, the loosening fan 120 is operated to blow air from the air outlet 122, the paper 100 is loosened, and the paper dust is removed. In the case of No in step S14, it is determined that there is no delay due to slippage, the sending clutch is turned off in step S16, and subsequently, in step S17, a conveying roller (not shown) The clutch is turned on, and the sheet 100a reaches a timing roller (not shown).
[0038]
In step S18, when the trailing end of the sheet 100a passes through the leading edge detection sensor 115 and the conveying roller 109 finishes feeding the sheet 100a, the conveying roller clutch is turned off, and in step S19, the sheet 100a is finally fed (subsequent feeding). It is determined whether or not there is no paper). In the case of No, the control is performed so that the next paper comes in succession, so that the delivery clutch is turned on and the transport cycle of the next paper is started. If Yes in step S19, the sheet 100a is synchronized with the image by a timing roller (not shown) and sent to the image forming unit.
[0039]
【The invention's effect】
Judgment of the necessity of air blowing operation is judged based on the paper feeding state, and blowing is automatically started only when necessary, minimizing noise such as wind noise and paper noise, eliminating unnecessary power consumption, and misfeeding. And a stable paper feeding operation is performed.
[Brief description of the drawings]
FIG. 1 is a perspective view of a sheet feeding device of the present invention.
FIG. 2 is a longitudinal sectional view of a main part of the sheet feeding device.
FIG. 3 is a top view of a main part of FIG. 1;
FIG. 4 is a diagram showing a part of an operation panel.
FIG. 5 is a flowchart illustrating a flow of a sheet feeding operation.
[Explanation of symbols]
Reference Signs List 100 paper 100a top paper 104 side regulating member 106 paper feed roller 107 separation roller 109 conveyance roller 110 paper upper surface sensor 112 detection unit 115 tip detection sensor 116 light shielding plate 118 photocoupler 120 separation fan 122 blowing port

Claims (11)

The paper stacked on the paper feed tray is sent out by the feeding means, and the separation means for separating the sheets one by one by a separation roller and the conveying means for conveying the separated paper are added to the upper side of the stacked paper. In a paper feeding device having a blowing port for feeding air and a paper separating means for passing air between the first and second upper sheets, a paper leading edge detection sensor detects a leading edge of the paper after a paper feeding operation is started. The apparatus further comprises control means for measuring a passage time until the detection, and controlling the sheet separating means so as to start blowing air from the air blowing port when the passage time is equal to or longer than a first reference time. Paper feeder. The sheet feeding device according to claim 1, wherein the leading end detection sensor is disposed between the separation unit and the transport unit. 2. The apparatus according to claim 1, wherein the first reference time is set so as to satisfy a relationship of a passage time during normal paper feeding <a second reference time <a first reference time <a maximum possible sheet passing time. 3. Paper feeder. The control means, when the passage time is continuously measured for a predetermined number of times or more within a range smaller than the first reference time and larger than the second reference time, blows air from the air blowing port. The sheet feeding device according to any one of claims 1 to 3, wherein control is performed so as to start. 5. The control device according to claim 1, wherein the control unit performs control so as to start blowing air from the air outlet when the passage time becomes larger than a predetermined variation width. 6. Paper feeder. 6. The control device according to claim 1, wherein during the period of blowing the air, after the start of the blowing, the set number of sheets to be fed is continued until the discharge is completed. 7. A paper feeder according to claim 1. The paper feeding device according to any one of claims 1 to 5, wherein the period of blowing the air is continued until the paper feeding tray becomes empty. The sheet feeding device according to any one of claims 1 to 5, wherein the period during which the air is blown is a period that continues until a use switch is made to a sheet feeding tray other than the sheet feeding tray. The sheet feeding device according to any one of claims 1 to 5, wherein the period of blowing the air is a period that continues until an operation of stopping the blowing of the air is performed. 10. An operation unit, wherein the operation unit can select any one of an automatic mode, an ON mode, and an OFF mode for air blowing, and only when the automatic mode is selected, the operation unit according to any one of claims 1 to 9. A sheet feeder to which the control of (1) is applied. The sheet feeding device according to any one of claims 1 to 10, wherein the control unit displays on the operation unit that a blowing operation is being performed during a period in which the air is blown.

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