JPH0585645A - Sheet forward end position correction device - Google Patents

Abstract

PURPOSE:To arrange a forward end position of a developed sheet correctly by a registration gate, and perform skew correction by continuing to feed the developed sheet for a predetermined time after the sheet is brought into contact with the registration gate. CONSTITUTION:A microcapsule sheet 12 where a latent image is formed is transported, and a developed sheet is taken from a paper feed cassette. At this time, a registration gate 34 rotates about a rotation shaft 35 to be at a skew correction position illustrated with a broken line, and the developed sheet guided by feed rollers 31b, 31c, and a transport chute 31d is brought into contact with the registration gate 34. A pressor spring 50 is pushed up by the registration gate 34 at the time, where the developed sheet is sent almost only by the feed roller 31b. BY continuing to drive the feed roller for several hundreds of milliseconds to about 1sec. after a sheet forward end is brought into contact with the registration gate 34, the forward end of the developed sheet is positioned correctly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet leading edge position correcting device for correcting the leading edge position and skew of a sheet in a copying machine, a printing machine or the like.

[0002]

2. Description of the Related Art As a conventional paper leading edge position correcting device,
As shown in Japanese Patent Application Laid-Open No. 58-100047, the leading edge of the sheet is brought into contact with the registration gate to position the sheet, and the registration roller and the registration pinch roller are arranged downstream of the sheet. It was structured to convey paper.

Further, in order to deal with the case where the sheet is conveyed in an inclined state in which the sheet is inclined with respect to the conveying direction for some reason, the sheet is bulged between the sheet feeding roller and the registration gate (hereinafter referred to as a buckle). That is, the skew was corrected using the buckle.

[0004]

However, since the leading edge of the sheet is pressed against the registration gate, a part of the leading edge of the sheet moves when the registration gate is retracted from the sheet path. Dragged to the registration path and jammed in the hole for retracting the registration gate provided in the paper path, or the paper is buckled, and the registration force between the registration roll and the registration pinch roller is restored by the paper's restoring force. Since the sheet rushes into the nip, there is a risk that a skew or a positional deviation may newly occur at the nip portion when the restoring force of the sheet is strong.

The present invention has been made in order to solve the above-mentioned problems, and eliminates variations in registration, ensures skew correction of a sheet, and prevents the occurrence of sheet jams. It is an object to provide a position correction device.

[0006]

In order to achieve this object, a sheet leading edge position correcting device of the present invention is provided with a sheet passage forming a sheet conveying path and a sheet passage arranged to the sheet passage to reach an image forming position. A pair of conveyance rollers for conveying, a skew correction position for advancing into the paper passage and interfering with the leading edge of the paper, and a release position retracted from the paper passage, are provided downstream of the pair of conveyance rollers. Paper leading edge regulating means,
The pair of conveyance rollers are rotated by a predetermined amount to convey the sheet, and the sheet tip position is corrected by the sheet tip regulation unit at the skew correction position, and then the sheet tip regulation unit is moved to the open position. And a control means for driving the pair of conveying rollers to feed back the sheet by a predetermined amount and then driving the pair of conveying rollers until the sheet reaches the image forming position.

[0007]

According to the present invention having the above structure, the sheet is driven by the pair of conveying rollers to come into contact with the sheet leading edge regulating means in the state of advancing into the sheet path, the positioning is performed, and the sheet is in the oblique state. If the sheet is fed, the sheet rotates with the abutted portion as a fulcrum, and the entire leading edge of the sheet comes into contact with the sheet leading edge regulating means.

After that, the control means moves the paper leading edge regulating means to the open position retracted from the paper passage, and also temporarily feeds the paper back by a predetermined amount by the pair of conveying rollers, and then the paper reaches the image forming position. Drive a pair of transport rollers.

[0009]

Embodiments will be described below with reference to embodiments embodying the present invention.

In the image forming apparatus of the present embodiment (hereinafter referred to as the copying machine 1), as shown in FIG.
A photosensitive paper consisting of (hereinafter referred to as microcapsule paper) and recording paper 28 (hereinafter referred to as developer paper) is used.

The surface of the support of the microcapsule paper 12 used in this embodiment is coated with microcapsules, and inside the microcapsules, a dye precursor which reacts with a developer, which will be described later, etc. Is included. A color developer is applied to the surface of the support of the color developing paper 28, and color is developed by reacting with the dye precursor. For details, see USP.
4399209, etc., and is omitted here.

An original platen glass 2 and an original platen cover 3 are disposed above the copying machine 1, and a desired original 4 is placed on the original platen glass 2 and the original platen cover 3 is closed.

Below the platen glass 2 in the upper part of the copying machine 1, a light source unit 5 having a halogen lamp 5a, a reflector 5b, a reflection mirror 8 and the like is provided along a shaft 13 which is installed in parallel with the platen glass 2. Are reciprocally movable. The light source unit 5 irradiates the original table glass 2 with light on a line in a direction orthogonal to the moving direction. The radiated light passes through the transparent original platen glass 2 and is reflected downward by the original 4 placed thereon.

Below the original platen glass 2, a mirror section 9 having reflecting mirrors 9a and 9b is provided so as to be movable separately from the light source section 5, and the light reflected from the original 4 is reflected by the reflecting mirror. The light is reflected in the order of 8, 9a and 9b and guided so as to be parallel to the moving direction of the light source unit 5.

A projection lens 7, which is normally fixed, and a filter 6 for adjusting the color tone of the copied image are disposed below the original platen glass 2, and the light reflected by the reflection mirror 9b is projected. It is incident on the lens 7. The lens 7
The light projected by is reflected by the reflection mirror groups 10a and 10b.

The light source unit 5 and the mirror unit 9 are connected by a wire (not shown) so that the moving distance of the mirror unit 9 is always 1/2 of the moving distance of the light source unit 5 by a drive motor (not shown). The original is appropriately driven so that it can be scanned.

An exposure table 11 for exposing the microcapsule paper 12 is arranged to the right of the reflection mirror 10b, and a reflection mirror 10c for switching an optical path is arranged between the reflection mirror 10b and the exposure table 11. It is set up. Image information on the original 4 is imaged on the microcapsule paper 12 arranged along the exposure table 11.

The reflecting mirrors 10a and 10b are usually fixed, but are set when enlarging or reducing the size of the latent image formed on the microcapsule paper 12, and the optical path is changed according to the change of the projection magnification m. In order to change the length, it is configured so as to be integrally movable in the axial direction of the shaft 13.

On the other hand, in the center of the copying machine 1, a cartridge 15 is arranged, and a long microcapsule paper 12 is provided.
Is housed in a cartridge 15 which is wound around the cartridge shaft 14 and is removable from the machine body. With the cartridge 15 set in the predetermined position inside the body,
The tip of the microcapsule paper 12 is pulled out toward the exposure table 11. Below the exposure table 11, a feed roller 19 and a dancer roller 21 for tension adjustment are arranged.

A pressure developing device 22 having a large diameter roller 22a, a backup roller 22b and a pressure roller 22c is arranged to the right of the dancer roller 21, and to the right of the pressure developing device 22 is provided. As will be described later, a separation roller 23 for separating the microcapsule paper 12 and the color-developing paper 28, which are in close contact with each other, is provided, and the microcapsule paper 12 is fitted between the separation roller 23 and the cartridge 15. A winding shaft 24 for holding is arranged.

The microcapsule paper 12 coming out of the upper portion of the cartridge 15 is guided to the tension roller 19 and
After passing above the exposure table 11, it passes through the dancer roller 21 and the pressure developing device 22, is further guided to the separation roller 23, and is then wound on the winding shaft 24. The unexposed microcapsule paper 12 that has left the cartridge 15 is kept in an unexposed state by a light-shielding cover (not shown).

Below the pressure developing device 22, a color developing paper 28 is provided.
A paper feed cassette 29 accommodating is stored. Above the paper feeding cassette 29, a suction cup-type paper feeding mechanism 30 for adsorbing paper by using negative pressure suction is arranged.
Are taken out one by one by the paper feeding mechanism 30. The transport chute 3 is provided between the paper feeding mechanism 30 and the pressure developing device 22.
1d, 31e and feed rollers 31a, 31b, 31c are arranged, and the color paper 28 is fed by the feed rollers 31a, 31e.
b, 31c, and the transfer chutes 31d, 31e, and the pressure developing device 22 is carried in.

A feed pinch roller 51 is provided so as to face the feed roller 31c, and the feed pinch roller 51 is provided.
The roller shaft 52 is pressed against the feed roller 31c by the pressing spring 50 fixed to the transport chute 31d.

Further, below the transport chutes 31d and 31e and the feed roller 31c, a plate-shaped registration gate 3 having a substantially L-shape rotatable about a rotation shaft 35 is provided.
4 are provided. When the registration gate 34 is rotated counterclockwise in FIG. 2 by a drive device such as a solenoid (not shown), the skew correction position is indicated by a broken line in the figure, and when the drive device is turned off, the registration gate 34 is biased by a spring or the like. When is rotated clockwise, the open position is indicated by the solid line in the figure. The transport chute 31e
Has a notch 36 facing the registration gate 34. When the registration gate 34 is at the skew correction position, the registration gate 34
Is configured to contact the pressing spring 50 and push up the pressing spring 50 to reduce the nip force between the feed roller 31c and the feed pinch roller 51.

A separation chute 27, which will be described later, is arranged on the right side of the pressure developing device 22.
A thermal fixing device 32 is disposed to the right of 7, and a discharge tray 33 that accommodates the color-developed paper 28 on which an image is formed is disposed to the right of the thermal fixing device 32.

Further, the copying machine 1 has an automatic loading function for automatically setting the microcapsule paper 12 on a predetermined conveying path in the apparatus. This is a function of automatically pulling out a leader film portion (not shown) attached to the front end portion of the microcapsule paper 12 into the apparatus, and then transporting the inside of the apparatus and winding it around the winding shaft 24. As a result, the microcapsule paper 12 following the leader film portion (not shown) is also wound on the take-up shaft 24.
It is wound up in and is set in the device.

Due to this automatic loading, the roller 1 is used for pulling out a leader film portion (not shown).
A half-moon roller 17 is provided between the cartridge 9 and the cartridge 15, and a separating chute 27 is rotatably mounted for guiding the winding shaft 24. Winding shaft 24
Around the circumference of, a Makitari guide wafer 25 and a Makitari guide sheet 26 are arranged for winding a leader film portion (not shown).

Next, referring to FIG. 3, a schematic configuration of a control system of the copying machine 1 will be described.

Programs for controlling various operations of the copying machine 1 are stored in the ROM 61 of the microcomputer 60,
Using the RAM 62 as a work area for control commands,
Controls various mechanisms.

The microcomputer 60 includes a light source unit 5
Document scanning system 65 including pressure and mirror section 9, pressure developing device 2
2, the paper feed mechanism 30, the thermal fixing device 32, the feed roller drive circuit 63, etc. are connected, and the feed roller drive circuit 63 is connected with a feed roller drive motor.

Next, the operation of the copying machine 1 will be described.

When the cartridge 15 is set in the copying machine 1, automatic loading is started.

The half-moon roller 17 rotates once to several times in the transport direction only when the automatic loading is started, and sends out the leader film portion (not shown) to the roller 20. After that, it is stopped and the subsequent transportation is performed by driving the roller 20.

The matrix guide wafer 25, the matrix guide shatter 26, and the separation chute 27 rotate to the positions shown by the alternate long and short dash line, and the leader film portion (not shown) attached to the leading end of the microcapsule paper 12 is taken up as a take-up shaft. When the auto-loading for winding around the 24 is completed, the Makitari guide wafer 25, the Makitari guide cutter 26, and the separation chute 2
7 returns to the position indicated by the solid line, and copying is possible.

When a copy start key (not shown) is operated, the light source unit 5 having the reflection mirror 8 and the halogen lamp 5a has a moving speed of 1 / mV, where V is the conveying speed of the microcapsule paper 12 and m is the projection magnification. And the reflecting mirrors 9a and 9b move at a moving speed of 1 / (2 m) V.

Since the conveying speed of the microcapsule paper 12 is synchronized with the moving speed of the mirror groups 8, 9a, 9b as described above, a predetermined amount of the original 4 is placed on the microcapsule paper 12 when passing through the exposure table 11. Line latent images are sequentially formed. In addition, the above-mentioned predetermined speed ratio is based on the setting value of the magnification,
It is predetermined.

Microcapsule paper 12 on which a latent image is formed
Is conveyed, and only the topmost color-developed paper 28 of the paper feed cassette 29 is taken out from the paper feed cassette 29 by the paper feed mechanism 30. The developer paper 28 taken out is fed by feed rollers 31a, 31b driven by a feed roller drive motor.
It is conveyed to the pressure developing device 22 by 31c and the conveying chutes 31d and 31e.

Here, the registration gate 34
Is at a skew correction position (indicated by a broken line in FIG. 2) rotated counterclockwise around the rotary shaft 35 by a drive device such as a solenoid (not shown), and the feed rollers 31a, 31
The color developing paper 28 guided by b, 31c and the conveying chute 31d contacts the registration gate 34.

At this time, the presser spring 50 is pushed up by the registration gate 34, and the feed roller 31c.
The nip force between the feed pinch roller 51 and the feed pinch roller 51 is reduced, and it is equivalent to that the color developing paper 28 is fed by the feed roller 31b only. Several hundred msec
By continuing to drive the feed roller 31b, the leading edge of the color-developing paper 28 is accurately positioned.

Even if the color-developing paper 28 is tilted during conveyance, since the nip force between the feed roller 31c and the feed pinch roller 51 is reduced, the color-developing paper 28 is moved (rotated) so as to follow the registration gate 34. ), The skew of the color-developing paper 28 can be corrected.

After the feed roller drive motor 64 is stopped,
When the registration gate 34 is moved to the open position (shown by the solid line in FIG. 2) retracted from the transport chute 31e, the force for pushing up the pressing spring 50 disappears and the nip force between the feed roller 31c and the feed pinch roller 51 is restored. However, the conveyance by the feed roller 31c becomes possible, and
The color-developed paper 28 whose skew has been corrected is held.

At this time, the color developing paper 28 tends to be drawn into the notch 36 as the registration gate 34 moves. Therefore, the feeding rollers 31a, 31b, 31c are reversed and the color developing paper 28 is moved by a predetermined amount (4-5 mm). ) Reverse feeding is performed, and the feeding rollers 31a, 31b, 3 are again fed from a position where the front end of the color-developing paper 28 is reliably separated from the registration gate 34.
1c is driven to convey the color paper 28 to the pressure developing device 22.

FIG. 4 is a drive timing chart of the registration gate 34 and the feed roller drive motor 64. The feed roller drive motor 64 rotates forward in the sections A and E and reversely rotates in the section C. In section B, the feed roller drive motor 64 is stopped in order to reliably switch the drive direction.

According to this timing chart, the developer 28 is conveyed by the feed rollers 31a and 31b in the section A until it comes into contact with the registration gate 34 to correct the skew, and the registration gate 34 is moved to the open position. In the section C after the elapse of time, it is fed back by the feed rollers 31b and 31c, is fed to a position reliably separated from the registration gate, and is conveyed to the pressure developing device 22 in the section E.

However, the time represented by the section D in FIG. 4 is actually provided for aligning the leading edge of the latent image portion of the microcapsule paper 12 and the leading edge of the color developing paper 28. Reference numeral 28 indicates a position where the latent image front end of the microcapsule paper 12 is conveyed to a predetermined position at a position where the microcapsule paper 12 is fed back in the section C. 12
Transported at a speed synchronized with.

The microcapsule paper 12 and the color-developing paper 28 are supplied to the pressure developing device 22 in a state of being in close contact with each other, and the microcapsule surface of the microphone capsule paper 12 on which the latent image is formed and the color-developing paper 28 are supplied. The developer application surface is sandwiched between the large diameter roller 22a and the pressure roller 22b in a state where they are in contact with each other on the inside, and pressure is applied.

By this pressure, the unexposed microcapsules are destroyed and an image is formed on the color developing paper 28.

The microcapsule paper 12 and the color-developing paper 28 discharged from the pressure developing device 22 are separated by the separating roller 23, and then the color-developing paper 28 is separated from the heat roller 3 of the heat fixing device 32.
After the color development is promoted by 2a to form an image, the paper is ejected to the paper ejection tray 33 by the paper ejection roller 32b. still,
The separated microcapsule paper 12 is taken up by a take-up shaft 24 via a separating roller 23.

The present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention.

For example, in the embodiment, the developer is brought into contact with the registration gate to correct the skew, and then the registration gate is immediately moved to the open position. It is also possible to carry out the reverse feeding and perform the tip position correction again to correct the skew more reliably. In this case, since the color-developing paper contacts the registration gate twice, there is an effect that it is possible to correct even a skew that cannot be sufficiently corrected by one contact.

[0051]

As is clear from the above description,
According to the present invention, by further continuing the feeding for a predetermined time even after the color-developing paper is brought into contact with the registration gate, the leading edge position of the color-developing paper can be accurately positioned by the registration gate and skew correction can be performed. ..

Further, when the registration gate is retracted from the transport chute, the nip force between the feed roller and the feed pinch roller on the upstream side of the registration gate is restored, so that the color developing paper is held at the required position and in the correct posture. It is possible.

Further, in order to avoid the influence of the registration gate, the color-developing paper is once fed backward and then fed to the image forming position, so that it is possible to feed it reliably without jamming.

[Brief description of drawings]

FIG. 1 is a central cross-sectional view showing a schematic structure of the copying machine.

FIG. 2 is an enlarged view of a color paper resist portion.

FIG. 3 is a block diagram of a control system of the copying machine.

FIG. 4 is a drive timing chart of a registration gate and a feed roller drive motor.

[Explanation of symbols]

 31c Feeding roller 31d Conveying chute 31e Conveying chute 34 Registration gate 51 Feeding pinch roller 60 Microcomputer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location // G03G 15/00 108 7369-2H

Claims (2)

[Claims] 1. A paper passage forming a paper conveyance path, a pair of conveyance rollers arranged in the paper passage to convey a sheet to an image forming position, and downstream of the pair of conveyance rollers.
A skew correction position that advances into the paper path and interferes with the leading edge of the paper, a paper leading edge regulating means that is movably provided at an open position that is retracted from the paper passage, and the pair of transport rollers are rotated by a predetermined amount to rotate the paper. After the sheet is conveyed and the sheet leading edge regulating unit at the skew correction position corrects the sheet leading edge position, the sheet leading edge regulating unit is moved to the open position, and the pair of conveying rollers reverses the sheet once by a predetermined amount. A sheet leading edge position correcting device comprising: a control unit that drives the pair of transport rollers until the sheet is fed and then reaches the image forming position. 2. The sheet leading edge position correcting device according to claim 1, wherein after the sheet leading edge position is corrected by the sheet leading edge regulating means at the skew correction position, the sheet is temporarily moved by a predetermined amount by the pair of conveying rollers. The paper is fed backward and conveyed again by a predetermined amount, the paper leading edge regulating means corrects the paper leading edge position, the paper leading edge regulating means is moved to the open position, and the paper is once fed backward by the prescribed amount by the pair of feeding rollers. And a control unit for driving the pair of conveyance rollers until the sheet reaches the image forming position.