JP2002128302A - Paper feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a space-saving paper feeder, provided with a plurality of paper receiving parts, which can surely feed paper sheet by sheet from a second paper storing part to a first paper storing part as a result surely prevent the paper from wrinkling and folding, even in the case of using the paper of high electric resistance easily charged with static electricity and even in a feed under an environment of high humidity. SOLUTION: This paper feeder comprises a first paper receiving part 11 arranged in the forward side in a paper conveying direction, a second paper storing part 12 arranged in the rearward side in the paper conveying direction, a paper transfer feed means 60 for transferring paper P loaded on the uppermost layer stored in the second paper storing part 12 onto the first paper storing part 11, and a float separating means 101 blowing air to a side surface upper part of the loaded paper stored in the second paper storing part 12 to float the paper in the uppermost layer to additionally separate it from the paper in the downward.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a copying machine, a facsimile, a printer, or the like.
The present invention relates to an improvement in a sheet feeding device having two sheet storage units.

[0002]

2. Description of the Related Art Conventionally, a medium-speed or high-speed copier or printer that consumes a large amount of paper, or a facsimile machine or the like that needs to store enough paper for a time period when paper cannot be supplied, such as at night or on holidays. In the forming apparatus, for example, A
It is necessary to store general-purpose paper such as four-size paper in an external paper feeder provided with a large-capacity paper storage part dedicated to A4-size paper. However, since this type of large-capacity sheet feeding device is installed side by side with the image forming apparatus, there is a problem that it cannot be installed in a small office.

In order to solve such a problem, for example, in Japanese Patent Application Laid-Open No. 6-100190, the first and second sheet storage sections are provided below the image forming section of the image forming apparatus. It is arranged in the supply direction, that is, in the left-right direction of the image forming apparatus main body, and when the downstream first paper storage unit becomes empty, the downstream first paper storage unit passes through the downstream first paper storage unit through the downstream first paper storage unit. Paper feeders have been devised so that paper is supplied. In such a paper feeder, for example, if A4 size paper, which is generally used in large quantities, is stored in the first and second paper storage units such that the short side of the paper is parallel to the paper transport direction, the first and second paper storage units can be used. The transport unit that supplies sheets from the second sheet storage unit and the first sheet storage unit to the image forming apparatus main body is accommodated only in the lower part of the image forming apparatus, and space saving can be realized.

[0004]

However, in the above-described paper feeder, as shown in FIG.
The feeding roller 311 of the second sheet storage unit 302 toward the mounting table 331 of
When the uppermost layer of the papers placed on the paper 2 is transported, the papers having a high electric resistance and being easily charged with static electricity are electrostatically attracted to each other, so that a plurality of papers can be simultaneously transferred to the first paper. It is transferred to the storage section 301. First paper storage unit 3
01 is transferred to the first sheet storage unit 30.
The first feeding roller 312 transports the sheet on the mounting table 331 to a sheet feeding position toward the image forming apparatus, and only the uppermost sheet is fed to the image forming apparatus by the action of the sheet feeding roller 313 and the separation roller 314. .

[0005] Of the sheets remaining on the mounting table 331 of the first sheet storage section 301, the uppermost sheet is operated by the sheet feed roller 313 and the separation roller 314 at the next sheet feed timing.
Although the sheet is fed to the image forming apparatus,
02, the next paper is transported, and the paper on the mounting table 331 and the paper fed from the second paper storage unit 302 collide with each other, and the contact portion between the two becomes wrinkled or broken. . In a high-humidity environment, the frictional resistance between the uppermost sheet and the sheet below the sheet increases due to the moisture absorbed by the sheet, and when the sheet is fed from the second sheet storage unit 302,
Double feeding and continuous feeding are likely to occur. As a result, the first
The paper remaining in the paper storage unit 301 and the second paper storage unit 302
The paper fed from collides with each other, and the contact portion between the two similarly wrinkles or breaks.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and is intended for use in the case of using paper having a high electric resistance and being easily charged with static electricity, and for feeding in a high humidity environment.
A space-saving paper feeder having a plurality of paper storage units, which can reliably feed sheets one by one from the second paper storage unit to the first paper storage unit and, as a result, can reliably prevent wrinkles and folding of the paper. It is intended to provide a device.

[0007]

The invention according to claim 1 is
A first paper storage unit arranged on the front side in the paper conveyance direction;
A second paper storage unit arranged on the rear side in the paper conveyance direction;
Sheet transfer means for transferring the uppermost layer of paper stored in the second paper storage unit onto the first paper storage unit; and blowing the air to the upper side of the stacked paper stored in the second paper storage unit to form the uppermost layer. And a floating separating means for separating the uppermost sheet and the lower sheet from each other.

[0008] According to the above configuration, air is blown to the upper side of the stacked sheets accommodated in the second sheet accommodating section to levitate the uppermost layer paper and to separate the uppermost layer sheet from the lower layer sheet. Means, the uppermost sheet and the lower sheet of the electrostatically attracted sheet and the like are reliably separated by air, and only one sheet of the uppermost layer is stored in the first sheet storage portion by the sheet transfer means. Be transported. In a high-humidity environment, air enters between the uppermost sheet and the lower sheet, thereby reducing the frictional resistance between the two sheets. Only one sheet of the uppermost layer is stored in the first sheet by the sheet transfer means. Transferred to the department.

According to a second aspect of the present invention, in the paper feeder of the first aspect, the floating / separating means is provided on the upstream side of the second paper storage section in the paper transport direction.

According to the above construction, the air from the flotation / separation means flows between the uppermost sheet and the lower sheet along the sheet transfer direction, so that the air spreads over the entire length in the transfer direction. Thus, a more complete separation of the uppermost sheet can be realized, and the frictional resistance can be more completely reduced between the uppermost sheet and the lower sheet.

According to a third aspect of the present invention, in the paper feeder according to the first or second aspect, the paper transporting means is a roller abutting a part of the paper width.

According to the above configuration, since the roller presses the sheet in the second sheet storage section from above, the sheet does not flutter, turn, or be inclined by the air from the flotation / separation means. . In addition, since the air flows through the portion other than the portion where the roller comes into contact with the sheet, the air is entirely spread between the uppermost sheet and the lower sheet, so that the uppermost sheet can be separated and the frictional resistance between the sheets can be reduced more completely.

According to a fourth aspect of the present invention, in the paper feeder according to any one of the first to third aspects, a suction means for sucking the uppermost sheet floated by the floating separating means is provided above the second sheet storage portion. It is characterized by:

According to the above construction, the uppermost layer paper is sucked by the suction means, and the gap between the uppermost layer paper and the sheet below the uppermost layer sheet is widened over a wide range. Can do it.

According to a fifth aspect of the present invention, there is provided a first sheet accommodating section arranged on the front side in the sheet conveying direction, a second sheet accommodating section arranged on the rear side in the sheet conveying direction, and the second sheet accommodating section. Paper transport means for transporting the uppermost stacked paper stored in the first paper storage unit to the first paper storage unit, and blowing air to the upper side of the stacked paper stored in the second paper storage unit to lift the uppermost paper sheet And a flotation separating means for separating the uppermost sheet from the lower sheet, and a sheet detecting means for detecting that there is no sheet in the first sheet accommodating portion. It is characterized in that the flotation / separation means starts operating when it is detected that no sheet is present in the section.

According to the above configuration, the sheet non-existence detection signal by the sheet detection unit of the first sheet storage unit coincides with the operation start timing of the floating separation unit, so that complicated control is not used. The flotation separation means can be activated.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a sheet feeding device according to the present invention. FIG. 1 shows the overall configuration of a copying machine as an image forming apparatus provided with a sheet feeding device 1 according to the present invention. This image forming apparatus includes a paper transport unit 4 having a registration roller 2 and a feed roller 3, an image forming unit 9 having a photosensitive drum 5, a developing unit 6, a transfer belt 7, a cleaning device 8, and the like; And a fixing unit 10 having A paper feeding device 1 is disposed below the image forming unit 9 and the like. The paper P fed from the paper feeding device 1 is supplied to the image forming unit 9 via the paper conveying unit 4. It has become so.

The paper feeder 1 includes a first paper storage section 11 arranged on the front side (downstream side) in the paper transport direction and a second paper storage section 11 disposed on the rear side (upstream side) in the paper transport direction. The storage unit 12 includes a storage unit 12 and a sheet transfer unit 60 configured to transfer the upper-layer paper P stored in the second paper storage unit 12 to the first paper storage unit 11. Further, on the upper right side of the first paper storage unit 11 in the drawing, the paper P stored in the storage unit is provided.
A flotation / separation means 14 for blowing air to the upper front surface to float the uppermost sheet P to separate it from the lower sheet P, and to suck the levitated uppermost sheet P and convey it to the sheet conveying section 4 An air feeding means 16 including a conveying means 15 is provided.

Air is blown around the second sheet storage section 12 adjacent to the upstream side (left direction in the drawing) of the upper surface of the sheet P stored in the storage section. Is provided at a position adjacent to the upstream side of the sheet transporting means 60 to suck only the uppermost sheet P of the sheet from the upper part of the sheet. A suction means 102 for lifting the object is provided. The arrangement of the flotation / separation unit 101 is a feature of the image forming apparatus according to claims 1 and 2 of the present invention, and the arrangement of the suction unit 102 is a feature of the image forming apparatus according to claim 4 of the present invention. Has become.

FIG. 2 is a detailed view of the sheet feeding device 1. The first and second sheet storage units 11 and 12 are respectively provided with mounting plates 17 and 18 on which sheets P of a predetermined size are mounted, and before and after the sheets P mounted on the mounting plates 17 and 18. It has a pair of front and rear pressing plates 19 to 22 for restricting the movement, and a pair of right and left pressing plates (not shown) for restricting the lateral movement of the paper P. The placement plates 17 and 18 are moved up and down by elevation driving means (not shown) so that the uppermost surface of the paper P placed on the placement plates 17 and 18 is moved to the transport position of the suction transport means 15. The sheet P is raised to the transfer position of the sheet transfer means 60 as the sheet P is consumed.

When all of the sheets P placed on the placing plate 17 of the first sheet accommodating section 11 have been consumed, the placing plate 17 is moved as indicated by a virtual line (17a) in FIG. In addition, by ascending to the uppermost guide position, it functions as a guide plate for the sheet P conveyed from the rear second storage unit 12. In addition, the first and second sheet storage units 1
When all the sheets P stored in both the sheets 1 and 12 have been consumed, the placing plates 17 and 18 are moved down to the lowest sheet supply position.

As shown in FIG. 3, the rear presser plate 20 disposed behind the first paper storage section 11 has an upper end slightly higher than the upper mounting plate 17 raised to the uppermost guide position. The dimension in the height direction is set so as to be located below (about 15 mm below the upper surface of the mounting plate 17), thereby securing a transfer path for the sheet P transferred from the second sheet storage unit 12 at the rear. It is supposed to be. Further, a front holding plate 19 provided in front of the first paper storage unit 11 and a front holding plate 21 provided in front of the second paper storage unit 12.
Is configured such that its installation height is set to be substantially the same as that of the rear pressing plate 20 of the first paper storage unit 11 so as to secure a transfer path for the paper P.

Further, the rear holding plate 22 of the second storage portion is provided.
Is located slightly above (for example, about 15 mm above) the uppermost surface of the stacked paper P, so that the stacked paper in the second storage unit does not shift from the rear pressing plate 22 to the rear. Has become. At least at the position of the levitation separating means 101 facing a levitation nozzle 128 to be described later, the rear holding plate 22 is cut out at least to the lowest position of the levitation nozzle 128, and the air from the levitation nozzle 128 is removed. It does not hinder.

The paper transport means (60) according to the present invention, wherein the first transport roller (61) disposed above the first paper storage section (11) and the second paper storage section (12) are provided. And the second transport roller 62 according to the above. The first and second transport rollers 61 and 62 are rotatably supported at the distal ends of brackets 64, respectively.
Each of the support frames 67 is pivotally supported on a rotation shaft 65 provided on the support frame 67 as a fulcrum. Also, the sheet transporting means 60 is provided on the uppermost layer surface of the sheet P in the first sheet storage unit 11.
The holding member 18 which is hung from the shaft P and is rotatably fixed to the shaft 53 is in contact with the vicinity of both ends in the width direction of the surface of the sheet P by its own weight. The holding member 18 has a tip end on the side of the sheet P curved in an arc shape toward the downstream side in the sheet transfer direction, and both ends in the width direction of the sheet P transferred from the second sheet storage unit 12 by the sheet transfer means 60. The side tip is received under it and lightly pressed by its own weight. This prevents the leading edge of the paper P at both ends in the width direction from being turned up by the air from the flotation / separation means 14 of the air paper supply means 16.

FIG. 3 is a perspective view showing the levitating / separating means 101 for levitating / separating the sheet in the second sheet accommodating section 12 of the present invention. The flotation separation means 101 is, as shown in the figure,
Air blow duct 12 extending in a direction perpendicular to the paper transport direction
0 and the connecting duct 12
1 and a blower 122 connected thereto.
The air duct 120 includes an upper wall 123 and a bottom wall 124.
And a pair of front and rear side walls 125 and 126 and a closing plate 127 for closing the front end.

Two floating nozzles 128 are provided at predetermined positions near both ends in the longitudinal direction of the blower duct 130 on the side wall 126 disposed at a position facing the second sheet storage section 12 among the side walls 125 and 126. It is arranged. The floating nozzle 128 has an opening of a predetermined length extending in the vertical direction of the side wall 126, and blows air from the opening to the upper side surface of the paper housed in the second paper housing unit 12, The uppermost sheet is configured to float.

The side wall 126 of the air duct 120
A plurality of separation nozzles 130 are arranged at predetermined intervals along the longitudinal direction of the blower duct 120 at a connection portion (corner portion) 129 between the blower duct 120 and the upper wall 123. The separation nozzle 130 includes an opening having a predetermined length extending in the longitudinal direction of the air duct 120, and as shown in FIG.
One of the uppermost layers of the upper layer paper floated by 28 is
It is configured to be lifted separately from other sheets.

FIG. 4 is a cross-sectional view (a cross-sectional view taken along the line BB) of the upper portion of the second sheet accommodating section 12 in FIG. It is. In FIG. 4, the uppermost position of the rear end of the paper when the second paper storage unit 12 is operated is represented by a virtual line together with the second paper storage unit area of the paper transfer unit 60.

As shown in FIG. 4, the main part 60 of the paper transport means is located substantially at the center of the paper P in the width direction. The rotating shaft 65 provided on the support frame 67 (not shown) is driven to rotate from the right side of FIG. 2 (the rear side in FIG. 2) by an unillustrated driving means such as an electric motor or the like. A force is transmitted to the second transport roller 62 by a gear mechanism and a clutch mechanism (not shown), and the second transport roller 62 is driven to rotate. That is, the two brackets 64 supported by the rotating shaft 65
, A power transmission means 66 composed of a transmission belt and a pulley is disposed, and the two second transport rollers 62 rotatably supported outside each of the two brackets 64.
Is driven and rotated in the direction in which the paper P is transported. The second transport roller 62 is rotated by the driving force transmitted from the rotating shaft 65 in a state in which the second transport roller 62 is in contact with the uppermost sheet P by its own weight, thereby transferring the uppermost sheet P. It is configured to transfer in the direction indicated by arrow A in FIG.

The second transport roller 62 has a built-in one-way clutch therein. When the roller transports the paper P, the second transport roller 62 is constrained by the rotary shaft 65 and transmits the rotational force from the rotary shaft 65 to the paper P. When the paper P is pulled downstream by the transport device downstream of the second transport roller 62, the restraint with the rotating shaft 65 is released and the paper P is freely rotated (left-rotated in FIG. 2). . Thereby, the transfer of the sheet by the second transport roller 62 is taken over by the transport unit downstream therefrom, and even if the transport drive of the second transport roller 62 is stopped, the transport can be smoothly taken over. The above configuration is equivalent to the first configuration in the first paper storage unit 11.
The same applies to the transport roller 61, and a description thereof will be omitted.

The support frame 67 of the paper transfer means 60
In addition, the first and second optical sensors which detect the upper limit position of the paper P stored in the first and second paper storage units 11 and 12 by detecting the swing displacement of the bracket 64, respectively. By detecting the reflected light of the light irradiated toward the upper surface of the sheet P and the upper limit detection switches 68 and 69, it is detected whether or not the sheet P exists on the placement plates 17 and 18, respectively. First and second empty sensors 70 and 71 including a photo sensor and the like are provided (FIG. 2).

Next, with reference to FIGS. 4 and 2, a mechanism for separating the sheet in the second sheet accommodating section 12 by the flotation / separation means 101 will be described. Floating nozzle 1 of levitation separating means 101
28 are located near both ends of the sheet P as shown in the figure.
When the airflow blown out from the floating nozzle 128 collides with the upper end of the sheet P, it enters between the sheets from the end of the sheet, and lifts the end of the sheet so as to turn sequentially from the topmost sheet (L1). The end of one sheet of the uppermost layer is the separation nozzle 130
Is lifted up to the airflow position, the airflow of the separation nozzle 130 is sent between the first and second sheets of the uppermost layer,
The gap between the two sheets is increased from the widthwise end to the width center. Also, the gap between the two sheets is increased from the upstream side to the downstream side of the second sheet storage unit 12 (L
2). As a result, a gap due to the air flow is formed between the two sheets in a portion other than a small area where the second conveyance roller 62 abuts, so that the electrostatic attraction between the two sheets is almost eliminated, and the gap between the two sheets is eliminated. Friction resistance is greatly reduced. as a result,
When the uppermost sheet is transported by the second transport roller 62, double feeding or continuous sheet feeding is not required.

This effect is further improved in the presence of the suction means 102. As shown in FIG. 5, the suction means 102 includes a blower duct 140 extending in a direction perpendicular to the sheet conveying direction, and a suction fan 142 connected to a base end of the suction duct 140 via a connection duct 141. I have it. The suction duct 140 has an upper wall 143 and a bottom wall 144, a pair of front and rear side walls 145, 146, and a closing plate 147 for closing a front end portion. The bottom wall 144
Are provided with a plurality of suction holes 148 at predetermined intervals in the longitudinal direction of the suction duct 140. The suction means 102 can suck and hold one sheet of the uppermost layer paper in the second sheet accommodating portion 12 which has been levitated and separated by the levitating / separating means 101. Thereby, the airflow of the separation nozzle 130 of the flotation separation means 101 is sufficiently blown into the gap between one sheet of the uppermost layer and the sheet immediately below the uppermost layer, and the separation of the uppermost layer paper and the reduction of friction between the two sheets are further effective. It is done on a regular basis.

Further, since the second transport roller 62 presses the sheet from above, the sheet does not flutter, turn over, or become skewed by the air from the flotation / separation means 101. In addition, since the roller 62 is in contact with the sheet P at a part of the sheet width, the air flows through the portion other than the sheet P to the entire space between the uppermost sheet and the lower sheet, so that the uppermost sheet can be separated or separated. The frictional resistance between sheets can be reduced more completely.

Next, the paper feeding from the first paper storage unit 11 to the image forming unit 9 will be described. First paper storage unit 1
As shown in FIG. 6, the flotation / separation means 14 includes a blower duct 155 extending in a direction perpendicular to the sheet conveying direction, and a blower 157 connected to a base end of the blower duct 155 via a connection duct 156. Is provided. The blower duct 155 includes an upper wall 158 and a bottom wall 159, a pair of front and rear side walls 160 and 161, and a closing plate 1 for closing a front end portion.
62.

A plurality of levitation nozzles 163 are provided on the side walls 161 of the side walls 160, 161 opposite to the installation portion of the first sheet storage unit 11, that is, on the side wall 161 disposed on the rear side in the paper feeding direction. 155 are arranged at predetermined intervals along the longitudinal direction. The floating nozzle 163 has an opening having a predetermined length extending in the vertical direction of the side wall 161, and by blowing air from the opening to the upper front surface of the paper housed in the first paper housing unit 11, The uppermost sheet is configured to float.

The side wall 161 of the ventilation duct 155
A plurality of separation nozzles 165 are arranged at predetermined intervals along the longitudinal direction of the air duct 155 at a connection portion (corner portion) 164 between the air duct 155 and the upper wall 158. The separation nozzle 165 has an opening having a predetermined length extending in the longitudinal direction of the air duct 155. As shown in FIG. 2, by blowing air toward the lower surface of the suction and conveyance unit 15,
The sheet adsorbed by the suction conveyance unit 15 is separated from other sheets.

Suction / conveyance means 15 of first paper container 11
As shown in FIG. 2 and FIG. 7, four drive rollers 41 and driven rollers 42 arranged in parallel at a predetermined interval in the sheet feeding direction, and the drive rollers 41 and driven rollers 42 And a conveying belt 44 wound around the driving roller 41 and the driven roller 42. Then, the drive shaft 54 connected so as to rotate integrally with the drive roller 41 is rotationally driven by an unillustrated drive means such as an electric motor, so that the transport belt 44 moves in the transport direction (feeding direction) of the sheet. (Paper direction).

The suction duct 43 includes an upper wall 45 and a lower wall 46 arranged vertically, a front wall 47 and a rear wall 48 arranged before and after in the sheet feeding direction, and left and right in the sheet feeding direction. It is formed in a box shape having a pair of side walls 49 and 50 provided. On the lower wall 46, four suction ports 51 are formed at positions corresponding to the installation portion of the transport belt 44. A vacuum pump 52 is connected to the side wall 50 via a connection tube 53.

The conveyor belt 44 is 0.5 to 1.5 m
It has a thickness of about m and is made of synthetic rubber material having a large number of through holes 55 formed therein. Then, the vacuum pump 52 sucks the air in the suction duct 43 to generate a negative pressure for sucking the sheet on the bottom surface of the transport belt 44.

In the first sheet storage section 11, the flotation / separation means 14 and the suction / conveyance means 1 constructed as described above
The paper P placed on the loading plate 17 is separated one by one by the air feeding means 16 comprising the transport belt 4.
4, and the sheets P are fed one by one to the image forming unit 9. All sheets P in the first sheet storage unit 11
Is fed, the mounting plate 17 has moved up to the position of the virtual line 17. In this state, the first transport roller 61 and the pressing member 18 are in direct contact with the mounting plate 17.

When all the sheets P in the first sheet storage unit 11 are exhausted, the first empty sensor 70 detects the absence of the sheet, and the control unit (not shown) of the sheet feeding device receives the signal to receive the signal. Floating / separating means 101 adjacent to two-sheet accommodating section 12
Then, the blower 122 and the suction fan 142 of the suction means 102 on the upper part of the second sheet storage section 12 are started. The first empty sensor 70 is mounted on the mounting plate 1 of the first paper storage unit 11.
7, a notch hole is provided in a portion of the mounting plate 17 that faces the sensor, and a notch hole is provided. The paper P is detected by detecting the reflection of
When the paper P disappears, the infrared light enters the notch hole, the reflection is no longer detected, and the absence of the sheet P is detected.

The blower 122 is started and the flotation / separation means 1
01 is floated and separated by the airflow from the floating nozzle 128 and the separation nozzle 130, and further separation is further promoted by the suction means 102. Then, an electric motor (not shown) is started to rotate the rotating shaft 65 of the sheet transfer means 60.
The second conveyance roller 62 is rotated by the power transmission means 66,
The separated uppermost sheet P is placed on the mounting plate 17 of the first sheet storage 11.
Transfer up.

The paper P transferred onto the mounting plate 17 of the first paper storage unit 11 is placed on the mounting plate 17 and the second transport roller 6.
2, is fed between the first transport roller 61 and the holding member 18 that have started rotating at the same time, and is pressed by the first transport roller 61 so that both ends do not float. Until it reaches. The paper P is further lifted to the position of the transport belt 44 of the suction transport unit 15 by receiving the airflow from the flotation / separation unit 14 of the air feeding unit 16, and is fed toward the image forming unit 9 by the transport belt 44. You.

The control unit of the sheet feeding device starts the electric motor at predetermined time intervals, and the second transport roller 62 feeds the sheets P one by one toward the first sheet storage unit 11 at the predetermined time intervals. Feed. When the number of sheets in the second sheet storage unit 12 decreases,
When the transport roller 62 moves downward by a predetermined amount, the bracket 64 rotates counterclockwise around the rotation shaft 65, and the second upper limit detection switch 69 detects a decrease in the number of sheets. In response to an instruction from the control unit of the sheet feeding device, the lifting / lowering driving means of the loading plate 18 is driven to rise,
The loading plate 18 moves up to a predetermined position. The above operation is
The process is repeated until the sheet on the stacking plate 18 runs out and the second empty sensor 71 detects the absence of the sheet.

As shown in the above-described embodiment, the provision of the floating separation means in the second paper storage portion makes it possible to separate the electrostatically attracted paper or the paper in a high humidity environment.
Only the uppermost sheet is transferred to the first sheet storage unit by the sheet transfer means. This eliminates the contact between the transfer paper from the second paper storage unit and the residual paper in the first paper storage unit due to the presence of a plurality of papers in the first paper storage unit, and avoids wrinkling and curling of the paper. it can.

Further, if the flotation / separation means is arranged on the upstream side of the second sheet accommodating portion, the air flow for separating the uppermost sheet can be spread over the entire length of the sheet in the sheet transport direction, and the separation effect can be improved. Furthermore, if the transfer means from the second paper storage unit is a roller that contacts a part of the paper width, the paper flaps due to the air flow from the flotation / separation means,
Turns and skew can be prevented. Furthermore, if the suction means is provided above the second sheet storage portion, the separated top sheet can be held, and the separation can be promoted more completely over a wide range.

The control itself can be simplified if the flotation / separation means and the suction means are started using the sheet absence signal from the sheet detection means in the first sheet storage section.

It should be noted that the present invention is not limited to only the above embodiments, and various embodiments are possible within the scope of the claims. For example, the flotation / separation unit may be provided on the side of the second sheet storage unit in the sheet width direction. In addition, the floating nozzle may be provided not only at both ends of the sheet but also at the center, or may be provided only at one end. Alternatively, the holes of the floating nozzle and the separation nozzle may be connected to form a T-shaped, H-shaped, or triangular shaped hole.

The rollers for transporting the paper from the second paper storage section may have a plurality of roller members arranged at arbitrary intervals not only in the central portion in the paper width direction but also in the entire width direction. The transfer means is not limited to a roller, but may be a belt-shaped transfer means. Further, the belt-shaped conveying means may be a means for sucking and conveying a sheet by an air suction means. Further, the belt-shaped transporting means may extend over the first and second sheet storage units.

The suction means provided on the upper portion of the second sheet storage section can have various shapes such as a square, a triangle, and a circle. Also, the suction hole is only at the center in the paper width direction,
Alternatively, only one end may be provided, or a slit may be opened over the entire length in the paper width direction. In order to balance the suction force, the area and shape of the suction hole may be individually changed, or the width of the slit may be changed depending on the location.

The paper feeding means from the first paper storage unit is
Various paper feeding means such as roller paper feeding and belt paper feeding can be employed in addition to the air paper feeding means.

[0053]

As described above, according to the first aspect of the present invention, the first sheet accommodating section arranged on the front side in the sheet conveying direction and the second sheet accommodating section arranged on the rear side in the sheet conveying direction. An accommodating section, sheet transport means for transporting the uppermost sheet accommodated in the second sheet accommodating section onto the first sheet accommodating section, and air to the upper side of the stacked sheets accommodated in the second sheet accommodating section. It is provided with flotation separating means for blowing the uppermost sheet to separate the lowermost sheet from the uppermost sheet by spraying, so that air is blown to the upper side of the stacked sheets stored in the second sheet storage section. Floating and separating means for separating the uppermost sheet from the lower sheet as well as floating the uppermost sheet, the uppermost sheet and the lower sheet of the electrostatically attracted sheet etc. Separated by the top layer of paper Only sheets are transported to the first sheet storage portion by the sheet transport means. In a high-humidity environment, air enters between the uppermost sheet and the lower sheet, thereby reducing the frictional resistance between the two sheets. Only one sheet of the uppermost layer is stored in the first sheet by the sheet transfer means. Transferred to the department.

According to the invention of claim 2, according to claim 1,
In the sheet feeding device of (1), the flotation / separation unit is provided on the upstream side of the second sheet storage unit in the sheet transport direction, so that air from the flotation / separation unit flows between the uppermost sheet and the lower sheet. The air flows along the transport direction of the paper, so that the air spreads over the entire length of the transport direction, thereby achieving a more complete separation of the uppermost paper, and between the uppermost paper and the lower paper. Friction resistance can be reduced more completely.

According to the invention of claim 3, according to claim 1,
In the sheet feeding devices of (1) and (2), since the sheet transporting means is a roller that abuts a part of the sheet width, the roller presses the sheet in the second sheet accommodating portion from above, so that the sheet is separated from the flotation / separation means. The paper flaps or rolls over with air,
There is no slant. In addition, since the air flows through the portion other than the portion where the roller comes into contact with the sheet, the air is entirely spread between the uppermost sheet and the lower sheet, so that the uppermost sheet can be separated and the frictional resistance between the sheets can be reduced more completely.

According to the invention of claim 4, according to claim 1,
In the sheet feeding devices of (1) to (3), since the suction means for sucking the uppermost sheet floated by the floating separation means is provided above the second sheet storage portion, the uppermost sheet is sucked by the suction means. The gap with the lower sheet is widened over a wide range, so that the uppermost sheet can be separated and the frictional resistance between sheets can be reduced more completely.

According to the fourth aspect of the present invention, the first sheet accommodating section arranged on the front side in the sheet conveying direction, the second sheet accommodating section arranged on the rear side in the sheet conveying direction, 2
Sheet transfer means for transferring the uppermost stacked paper stored in the paper storage unit onto the first paper storage unit; and blowing the air to the upper side of the stacked paper stored in the second paper storage unit, thereby forming the uppermost paper sheet. And a sheet detecting means for detecting that there is no sheet in the first sheet accommodating portion. The sheet detecting means includes a first sheet detecting means for detecting that no sheet is present in the first sheet accommodating portion. When it is detected that the sheet is not present in the sheet storage section, the flotation / separation means starts to operate, so that the flotation / separation means can be started without using complicated control.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating an overall configuration of an image forming apparatus including a sheet feeding device according to the present invention.

FIG. 2 is a cross-sectional view illustrating a specific configuration of a sheet feeding device.

FIG. 3 is a perspective view illustrating a specific configuration of a floating separation unit of a second sheet storage unit.

FIG. 4 is a cross-sectional view illustrating a specific configuration of a sheet transfer unit. (B-B sectional view of FIG. 2)

FIG. 5 is a perspective view illustrating a specific configuration of a suction unit of a second sheet storage unit.

FIG. 6 is a perspective view showing a specific configuration of a flotation / separation unit of the first paper container.

FIG. 7 is a side view showing a specific configuration of a suction conveyance unit of the first paper storage unit.

FIG. 8 is a cross-sectional view illustrating a conventional example of a sheet feeding device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Paper feeder 11 1st paper storage part 12 1st paper storage part 60 Paper transfer means 70 1st empty sensor (paper detection means) 101 Floating separation means 102 Suction means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masami Fuchi Kyocera Mita Co., Ltd. In-house F-term (reference) 1-28-2 Tamatsuzo, Chuo-ku, Osaka 3F343 FA02 FB02 FB03 FB04 FC01 GA01 GB01 GC01 GD01 HA33 HB04 HC22 HC28 HD16 JA01 JD03 JD27 JD28 JD39 KB03 LC08

Claims (5)

[Claims] 1. A first array arranged on the front side in the paper transport direction.
A paper storage unit and a second paper storage unit arranged rearward in the paper conveyance direction.
A sheet accommodating section, sheet transport means for transporting the uppermost stacked sheet accommodated in the second sheet accommodating section onto the first sheet accommodating section, and an upper side of the sheet accommodating in the second sheet accommodating section. A sheet feeding device, comprising: a flotation separating unit that blows air to levitate the uppermost sheet and separates the uppermost sheet from the lower sheet. 2. The sheet feeding device according to claim 1, wherein the floating separation unit is provided upstream of the second sheet storage unit in a sheet transfer direction. 3. The sheet feeding device according to claim 1, wherein said sheet transporting means is a roller abutting a part of a sheet width. 4. The paper feeder according to claim 1, further comprising a suction unit provided above the second sheet storage unit for sucking the uppermost sheet floated by the floating separation unit. 5. A first arrangement arranged on the front side in the sheet transport direction.
A paper storage unit and a second paper storage unit arranged rearward in the paper conveyance direction.
A sheet accommodating section, sheet transport means for transporting the uppermost stacked sheet accommodated in the second sheet accommodating section onto the first sheet accommodating section, and an upper side of the sheet accommodating in the second sheet accommodating section. A flotation / separation unit for blowing air to levitate the uppermost layer of paper and separating the uppermost layer of paper from a lower paper; and a paper detection unit for detecting that no paper is present in the first paper storage unit. The paper detecting means is the first
A sheet feeding device characterized in that the flotation / separation unit starts operating when it detects that no sheet is present in the sheet storage unit.