JPH1020574A - Separating and carrying method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely attract and separate even a stiff paper by increasing the potential by electrification in the surface of a belt-like member. SOLUTION: The uppermost page of a document is attracted, separated and carried by the electrostatic attracting action of an AC electric field formed on the surface of the belt-like member by an AC power source 253, and AC power source witch 253a and an electrifying roller 225 which are an electrification means. When the surface of a turning-over belt 208 being the double- structure belt-like member consisting of the front surface having an insulating layer and the back surface having an electrical conductive layer is electrified, an AC voltage is impressed on the electrical conductive layer of the back surface of the belt-like member by a voltage impressing means consisting of a high-frequency power source 253b, a high-frequency power source switch 253c and a change-over switch 253d.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to paper feeding for an image forming apparatus such as a copying machine, document transport for an image reading apparatus, and
A method and apparatus for separating and transporting paper and the like applied to turning pages of a book, and more specifically, a separating and transporting apparatus and apparatus for attracting and separating paper and the like by electrostatic attraction of an alternating electric field charged and formed on the surface of a belt-shaped member. About.

[0002]

2. Description of the Related Art Conventionally, as a method of separating and transporting a document page of a book original page turning apparatus or a transfer sheet of a copying machine, a separating and transporting method using frictional force or a separating and transporting method using air suction or the like is generally used. Is known to.

However, in the former separation / conveyance method using frictional force, a frictional member made of a rubber material or the like is used as separation means for paper or the like. In addition, there is a problem that the paper is damaged by the pressure applied at the time of separation.

[0004] In the latter separation and transport method using air suction or the like, there is a problem that the air suction sound at the time of separation is loud and generates noise, which is not suitable for use in an office and the apparatus itself becomes large.

[0005] Therefore, an uneven electric field is formed on the dielectric belt, and the sheet is attracted to the dielectric belt by the electrostatic attraction force of the uneven electric field, so that the stacked sheets (pages of the original) are stacked.
The present applicant has previously proposed a method and an apparatus for separating and transporting a document by a static adsorption separation method (a page turning apparatus for a book).

[0006]

In the method and apparatus for separating and conveying by the above-mentioned electrostatic attraction method, no pressure or noise is generated at the time of sheet separation. The problem of the separation and transfer method according to the method can be solved. Further, according to the method and the apparatus for separating and conveying, since the sheet does not depend on the frictional force or the air suction force, even if the sheet is very thin, the sheet can be separated and conveyed without causing double feeding (multiple sheet conveying). .

However, in the separation and conveyance method and apparatus based on the previous electrostatic adsorption method, when the paper to be separated and conveyed is thick, even if the maximum charging potential in the conventional charging method is used, the dielectric belt is not charged. The strength of the paper to be separated becomes greater than the electrostatic attraction force of the formed uneven electric field, and the paper adhered to the dielectric belt may not be separated. There is a problem that the range of paper that can be conveyed is narrowed (the types of paper that can be used are limited).

[0008]

SUMMARY OF THE INVENTION According to the present invention, when the surface of a belt-shaped member is charged, an alternating voltage that generates a charging potential larger than the conventional peak value is applied to the conductive material on the back surface of the belt-shaped member. It is to be applied to the layer. As described above, by generating a charging potential higher than the conventional peak value on the surface of the belt-shaped member, the charging potential on the surface of the belt-shaped member, which causes a reduction in the range of paper that can be separated and conveyed, is increased. Paper with high strength can be surely separated by suction.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the separation / conveyance method of the present invention, a paper or the like is adsorbed and separated / conveyed by an electrostatic adsorption action of an alternating electric field formed on the surface by a charging means. The front surface is an insulating layer and the back surface is a conductive layer. When charging the surface of the belt-shaped member having the double structure, an alternating voltage is applied to the conductive layer on the back surface of the belt-shaped member by voltage applying means for applying an alternating voltage to the conductive layer on the back surface of the belt-shaped member. .

The alternating voltage applied to the conductive layer on the back surface of the belt-shaped member may be a positive or negative alternating voltage substantially equal to the charging start voltage of the belt-shaped member. It is preferable in increasing the value.

The alternating voltage applied to the conductive layer on the back surface of the belt-shaped member may be set to a frequency that is 5 to 15 times the frequency of the alternating voltage for charging the surface of the belt-shaped member.

Further, there is provided an application circuit switching means for switching a circuit for applying an alternating voltage to the back surface of the belt-shaped member to a side where the conductive layer on the back surface of the belt-shaped member is grounded, and to charge the surface of the belt-shaped member. Thereafter, when a sheet or the like is adsorbed on the surface of the belt-shaped member, an application circuit of a voltage application unit that applies an alternating voltage to the conductive layer on the back surface of the belt-shaped member is provided. Switching to the side to be grounded is effective in stabilizing the charging potential on the surface of the belt-shaped member and stabilizing the sheet attracting force.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention, in which a separating / transporting device is mounted on a book document page turning / reading device proposed by the present applicant. However,
Descriptions of configurations, operations, and the like in a range that can be clearly recalled from the description of this specification will be omitted or simplified in order to avoid complication. In the present invention, the page turning function and the image reading function of the book manuscript can be configured independently of each other. Here, both of the page turning function and the image reading function are incorporated in one unit. The device was the example.

First, the configuration of the scanner unit 30 in this embodiment will be described. FIG. 1 shows a TPS (Turn the Page Scan) according to the present embodiment.
r; page turning reading device). The upper half of the main body of the TPS is a scanner unit 30. The scanning unit 200 travels in the scanner unit 30 in the left-right direction in FIG. The scanned original BO is scanned.

FIG. 2 shows the configuration of the scanning drive system of the scanning unit 200. FIG. 2 is a scanning drive system of the scanning unit 200 viewed from above the apparatus main body.
The timing belt 312 is located at the back of the
The timing belt 313 is connected to the pulley 305 and the two-stage pulley 30 on the front side of the apparatus body by the four-stage and three-stage pulleys 302.
6 extend in the left-right direction. Here, the rotating shafts of the pulley 304 and the pulley 305 are supported by springs 307 and 308, respectively, and apply predetermined tension to the timing belts 312 and 313. 3
The step pulley 302 is connected to a motor pulley 301 by a timing belt 310 and to a two-step pulley 306 by a timing belt 311. The timing belt 311 obtains a predetermined tension by pulling the idler 303 outward with a spring 309. The scanning unit 200
The back side and the near side are fixed to the timing belts 312 and 313 by clamps 315, respectively, and are driven via the timing belts 312 and 313 by the rotation of the scanner motor 106 that drives the rotation shaft of the motor pulley 301.

FIG. 3 shows the configuration of the scanning unit 200 in this embodiment. In FIG. 3, original pressing rollers 281a and 281b are provided on the lower left and right of the scanning unit 200, respectively.
Outside the sheet take-up rollers 280a, 280
80b are rotatably supported respectively. The central ends of the left and right independent document pressing sheets 282a and 282b are wound around the sheet take-up rollers 280a and 280b, respectively.
The outer ends of the a and 282b are fixed to side plates of the scanner unit 30, respectively.

As shown in FIG. 4, sheet winding gears 232a and 232b are fixed to the outer ends of the winding roller shafts 251a and 251b, respectively. Each of the idle gears 23 is fixed to a drive rack 231 having both right and left ends fixed to a side plate of the scanner unit 30 and having teeth over substantially the entire length.
They are in mesh with each other via 3a and 233b. 4, when the scanning unit 200 travels, the sheet take-up gears 232a, 232b rotate together with the idle gears 233a, 233b, and the respective take-up roller shafts 251a, 251b, and the respective springs 252.
a, 252b, and each sheet take-up roller 280
a, 280b via the original holding sheets 282a, 282b.
Pulling out and winding of 82b are performed, and the tension of the left and right sheet winding rollers 280a and 280b is always maintained substantially constant.

On the other hand, as shown in FIG. 3, a platen glass 205 for reading the original and a turning belt 208 for turning the pages of the original are arranged between the original pressing rollers 281a and 281b. This platen glass 205
As shown in FIG. 3, two fluorescent lamps 201 and 202 for illuminating the original are arranged on the left and right sides of the original reading unit, respectively, as shown in FIG. These fluorescent lamps 201, 202
In FIG. 3, the book original image illuminated by the first mirror 219 is reflected by the first mirror 219, then alternately reflected by the second mirror 220 and the third mirror 221 and finally transmitted through the lens 216 to be reduced on the CCD 101. It is imaged. Further, the turning belt 208 is stretched around a turning belt driving roller 223 and a turning roller 224, and a charging roller 225 is provided above the turning belt 208 and outside a portion slightly away from the turning belt driving roller 224. Are arranged in contact with each other.

Further, as shown in FIG. 4, a turning belt driving gear 234 is fixed to the end of the driving shaft of the turning belt driving roller 223, and the turning belt driving gear 234 is connected via an idle gear 235. , Drive rack 2
32 is engaged. Thereby, the scanning unit 20
0, the turning belt drive gear 234 rotates along with the idle gear 235 along the drive rack 232, and the turning belt driving roller 223 rotates the turning belt 2 at the same speed as the moving speed of the scanning unit 200.
08 rotates.

Next, the turning operation of the scanner unit 30 will be described. FIG. 5 is a diagram illustrating the operation of the page turning section of the scanning unit 200 according to the present embodiment. The turning belt 208 in this embodiment is made of PET, P
C, PVC, etc., and the surface layer has a surface resistance of 10 ¹⁴
A high-resistivity film (insulating layer) of Ω or more, and a back layer thereof is formed of a double-layer resin film composed of a low-resistance film (conductive layer) having a surface resistance of 10 ⁸ Ω or less.

The turning belt driving roller 223 is
As shown in FIG. 12, the surface of a metal roller is coated with conductive rubber, and the metal roller is configured to apply an alternating voltage to the back surface of the turning belt 208 via a high-frequency power switch 253c. Are connected. Further, the turning belt driving roller 2
Reference numeral 23 designates a circuit for applying an alternating voltage to the back surface of the turning belt 208 to a side where the conductive layer on the back surface of the turning belt 208 is grounded via a changeover switch 253d as application circuit switching means. It is configured.

On the other hand, the charging roller 225 is composed of a medium-resistance rubber roller and a core, and an AC power supply 253 is connected to the core via an AC power switch 253a.

Prior to forming the charged pattern on the surface of the turning belt 208 prior to the page turning operation shown in FIG. 5, the changeover switch 253d is set to "OF" as shown in FIG.
F ”to turn on the AC power switch 253a and the high-frequency power switch 253c. At this time, while moving the turning belt 208 at a linear velocity of 227 mm / s, the AC power 253 receives ± 2 kV, 75 Hz high power. A high-frequency power source 253b generates ± 800 V, 750
Hz voltage is generated. Thereby, the turning belt 2
08, a charging pattern having a pitch of about 3 mm is formed.

When the uppermost page 254 (paper) of the book BO is attracted to the surface of the turning belt 208, the high-frequency power source 253b is applied to the conductive layer on the back surface of the turning belt 208.
When the voltage from is applied, the turning belt 20
8 may have a small repulsive force on the paper adsorbed on
The repelling force may cause the sheet adsorbed on the turning belt 208 to drop.

Therefore, in the embodiment of the present invention, after forming a charged pattern on the surface of the turning belt 208,
When turning over the top page 254 of O, FIG.
In 2, the AC power switch 253a and the high frequency power switch 253c are turned "OFF", and then the changeover switch 253d is turned "ON" to connect the conductive layer on the back surface of the turning belt 208 to the ground (earth) side. Then, the top page 254 of the book BO is attracted to the surface of the turning belt 208 in this state by an alternating electric field generated from the charging pattern on the surface. As described above, when the sheet is attracted to the turning belt 208, the charge on the back surface is grounded to stabilize the charging potential on the surface of the turning belt 208 and stabilize the sheet attracting force on the surface of the turning belt 208. Can be.

In the conventional method of charging the front surface of the turning belt 208, as shown in FIG. 14, the back surface of the turning belt 208 is grounded to perform charging. The charging characteristics are shown in FIG.
As shown in FIG. 5, at the charging start voltage of the AC power supply 253,
The surface of the turning belt 208 is not charged, and the AC power 25
When the applied voltage from No. 3 exceeds the charging start voltage, the charging potential is charged on the surface of the turning belt 208 with a slope of about 1. Further, in this conventional charging method, the turning belt 20
If the voltage applied to the surface of No. 8 becomes too large, the positive and negative charging potentials start to be irregularly disordered, and the average charging potential (pk-pk) decreases.

Therefore, in the present invention, the turning belt 208
When the surface of the turning belt 208 is charged, a positive / negative alternating voltage (voltage from the high-frequency power supply 253b) substantially equal to the charging start voltage of the turning belt 208 is applied to the conductive layer on the back surface of the turning belt 208. . According to this charging method, as shown in FIG.
08 is charged at a gradient of about 1 from an applied voltage of about 0 V, and a charging potential larger than the peak value of the conventional charging potential shown in FIG. 15 is obtained.

As described above, in the separation transport method and apparatus according to the present invention, the charged potential on the surface of the
The original B
The top page 254 of O and the like can be held on the turning belt 208 with a large suction force, so that a thick paper with relatively strong stiffness can be separated and conveyed. In the present embodiment, an example is shown in which the separation transport method and apparatus of the present invention is applied to a page turning method and apparatus of a book document. The present invention can also be applied to document transport of a reading device.

When a document reading operation is started,
The scanning unit 200 at the left end home position of the scanner unit 30 starts traveling rightward. The platen glass 205 of the scanning unit 200
When the original reading position of the original BO is on the left page of the original BO, as shown in FIG. 6, the optical system of the scanning unit 200 starts the reading operation of the original BO, and moves the original surface of the original BO to the left page. To the right page. The reading start position of the scanning unit 200 here depends on the size (size) of the book BO. In this manner, when the optical system of the scanning unit 200 finishes reading up to the right end of the book BO, the scanning direction of the scanning unit 200 is reversed as shown in FIG. 7, and as shown in FIG. The page turning operation of the right page of the book BO after this reading is started.

When the page turning of the book BO is started, the turning belt 2 is preceded by the page turning operation.
08 on the surface of the original BO
Overlaps with the top page 254a. Then, as shown in FIG. 8, when the leading end of the topmost page 254 exceeds the lower center of the turning belt 208,
Is lifted to the position shown by the solid line in FIG. 5 by the action of a solenoid (not shown). As a result, the uppermost page 254a of the book BO is formed by the attraction force of the charge pattern formed on the surface of the turning belt 208 due to the uneven electric field.
The end of the top page 254a is lifted together with the turning belt 208 by being attracted onto the surface of the turning belt 208. The attraction force due to the uneven electric field has a characteristic that pages other than the top page 254 are not attracted.

As described above, the uppermost page 25 of the book BO
After turning up the scanning unit 4, the scanning unit 20 remains in this state.
0 is moved toward the end home position as shown in FIG.
As shown in FIG. 9, a pair of upper and lower page guides 2 reliably transported and separated and arranged on the right side of the scanning unit 200.
27, 228 (FIG. 3) and scan unit 2
00 is sent out to the right outside. At this time, a page turning sensor 214 (FIG. 3) mounted on a page guide 227 on the upper side of the scanning unit 200 detects a document page sent to the right outside of the scanning unit 200, and
It is determined that this original page has been turned normally.

As is clear from the above description, in this embodiment, the original page turned up by the page turning operation of the scanning unit 200 is held in a natural posture without being rounded or bent. The scanning unit 200 can be reduced in size because there is no need to dispose the turned-up original page in the scanning unit 200, and it is not necessary to provide a page storage unit for storing the turned-up original page.

Next, as shown in FIG.
When the top page 254 is turned up to the binding portion of the book original, the turning belt 208 is returned to the original position (broken line position in FIG. 5). In this state, when the scanning unit 200 is further moved toward the end home position,
As shown in FIG. 5, the turned-up original page is pulled by the binding portion of the book original and returns between the pair of page guides 227 and 228 so as to be overlapped on the left page of the book BO. It is discharged from the scanning unit 200.

When the turned-up original pages are all superimposed on the left page of the book original BO, the scanning unit 200 finishes one original reading and page turning operation for a two-page spread original. Here, this book manuscript BO
As described above, when repeatedly performing the document reading / page turning operation on the document, or repeatedly performing only one of the document reading and the page turning operation,
At the same time as the turned-up original pages are all overlaid on the left page of the book original BO, the direction of movement of the scanning unit 200 is reversed so that the reciprocating operation of the scanning unit 200 in the shortest course with respect to the original surface of the book original. repeat.

[0035]

The present invention is embodied in the form described above and has the following effects.

When charging the surface of the belt-shaped member,
The conductive layer on the back surface of the belt-shaped member has an alternating voltage having a frequency of 5 to 15 times the frequency of an alternating voltage that is substantially equal to the charging start voltage of the belt-shaped member and that charges the surface of the belt-shaped member. By applying, a charging potential higher than the conventional peak value can be generated on the surface of the belt-shaped member, so that the charging potential on the surface of the belt-shaped member is increased, and the paper having a strong stiffness is reliably adsorbed. Be able to separate.

After charging the surface of the belt-like member,
When adsorbing paper or the like on the surface of the belt-shaped member,
By switching the application circuit of the voltage applying means for applying an alternating voltage to the conductive layer on the back surface of the belt-shaped member to the side where the conductive layer on the back surface of the belt-shaped member is grounded, the charging potential on the surface of the belt-shaped member is changed. Can be stabilized to stabilize the suction force of the sheet, so that the reliability of separation and conveyance of the sheet and the like can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating an overall configuration of a main body of a book original page turning reading apparatus (TPS) embodying the present invention.

FIG. 2 is a schematic plan view showing a driving mechanism of a scanning unit in the TPS.

FIG. 3 is a schematic sectional view of the scanning unit.

FIG. 4 is a schematic side view of a turning belt driving mechanism in the scanning unit.

FIG. 5 is a schematic cross-sectional view of a main part of the scanning unit showing a page turning operation of the scanning unit in the TPS.

FIG. 6 is a transition diagram at a left-page image reading position of the scanning unit in a page turning operation mode of the scanning unit.

FIG. 7 is a transition diagram at the right page image reading completion position of the scanning unit in the page turning operation mode of the scanning unit.

FIG. 8 is a transition diagram at a right page turning start position of the scanning unit in the page turning operation mode of the scanning unit.

FIG. 9 is a transition diagram in the middle of turning the right side of the scanning unit in the page turning operation mode of the scanning unit.

FIG. 10 is a transition diagram at a right page turning end position of the scanning unit in the page turning operation mode of the scanning unit.

FIG. 11 is a transition diagram in the middle of discharging the right page of the scanning unit in the page turning operation mode of the scanning unit.

FIG. 12 is a schematic cross-sectional view illustrating a configuration of a charging unit of the turning belt according to the embodiment of the present invention.

FIG. 13 is a diagram showing a charging potential characteristic of the turning belt in the example of the present invention.

FIG. 14 is a schematic cross-sectional view illustrating a configuration of a charging unit of a turning belt in a conventional example.

FIG. 15 is a diagram showing a charging potential characteristic of a turning belt in a conventional example.

[Explanation of symbols]

 1 Document Plate 106 Scanner Motor 200 Scanning Unit 208 Turning Belt 208a End of Suction Surface of Turning Belt 214 Page Turning Sensor 223 Turning Belt Driving Roller 224 Turning Roller 225 Charging Rollers 227 and 228 Page Guide 253 AC Power Supply 253a AC Power Switch 253b High Frequency Power Supply 253c High frequency power switch 253d Changeover switch 254 Top page 281a, 281b Document holding roller BO Book original

Claims (4)

[Claims] An alternating electric field is formed by charging means on the surface of a double-structured belt-like member having an insulating layer on the front surface and a conductive layer on the back surface, and the belt-like member is electrostatically attracted by the alternating electric field. A separating and conveying method, wherein an alternating voltage is applied to a conductive layer on a back surface of the belt-shaped member when the surface of the belt-shaped member is charged in a separation and conveyance device that suction-separates and conveys paper or the like. 2. The separating and conveying apparatus according to claim 1, wherein the alternating voltage applied to the conductive layer on the back surface of the belt-shaped member is a positive or negative alternating voltage substantially equal to the charging start voltage of the belt-shaped member. Method. 3. The method according to claim 1, wherein the alternating voltage applied to the conductive layer on the back surface of the belt-shaped member has a frequency that is 5 to 15 times the frequency of the alternating voltage for charging the surface of the belt-shaped member. The method according to claim 1. 4. An alternating electric field is formed by charging means on the surface of a double-structured belt-like member having an insulating layer on the front side and a conductive layer on the back side, and the belt-like member is electrostatically attracted by the alternating electric field. A separation / conveyance device that adsorbs / separates and transports paper or the like by applying a voltage to the conductive layer on the back surface of the belt-shaped member when charging the surface of the belt-shaped member; After charging the front surface, when adsorbing paper or the like on the front surface of the belt-shaped member, a circuit for applying an alternating voltage to the back surface of the belt-shaped member,
An application circuit switching means for switching a conductive layer on a back surface of the belt-shaped member to a grounding side.