JPH02305743A - Sheet transfer device - Google Patents

Abstract

PURPOSE:To facilitate processing a paper jam by moving a carriage unit to a predetermined position along a sheet containing means and stop it when the jam detected by a detecting means at the time of transfer of sheets to the sheet containing means. CONSTITUTION:When a paper jam occurs in transfer and discharge ways for a carriage unit 1, the paper jam is detected by sensors 46, 47, and the carriage 1 moves to a predetermined position (position of a sensor 51) along a sheet containing means (middle tray) 183 and stops at the position. Space over the sheet containing means 183 is opened by this. A jam sheet S can thus be eliminated easily.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a sheet conveying device, and more particularly, to a sheet conveying unit of a duplex/multiplex unit installed in an image forming apparatus such as a copying machine. in between.

(■) Conventional technology Conventionally, as a recording device such as a copying machine or a printer, there has been an automatic duplex copying machine using an electrostatic recording method, and the configuration of the device that performs automatic duplexing of this copying machine can be roughly divided into two types. be done.

The first automatic double-sided configuration is the copying machine P2 shown in FIG.
The basic structure is an S-shaped bus located in the center.

In the figure, an original is placed on a platen 152 disposed at the top of a copying machine main body 151 of a copying machine P2, and the original is scanned by an optical system 156 in the copying machine main body 151 to an image forming section 157. A latent image is formed by exposing the photosensitive drum. By developing this latent image,
A toner image is formed in the image forming section 157. The copying machine main body 151 is provided with a plurality of cassettes 159 and 160 for storing sheets S, a manual feed cassette 161, etc., and a cabinet 162 in which the copying machine main body 151 is placed. A large number of sheets S are also stored in the section 163. These sheets S are fed to a paper feed section 1 consisting of rollers, separation rollers, etc. provided in each cassette.
The paper is fed by 65.

A toner image is transferred to the sheet S fed by a paper feeding unit such as a paper feeding unit 165 in a transfer unit 166 of an image forming unit 157, and then transferred to a fixing unit 169 by a conveyor belt 167.
After the toner image is fixed by heating and pressurizing the sheet S conveyed to
71 and is discharged onto the discharge tray 172.

Here, when performing double-sided copying in which images are formed on both sides of one sheet S, or multiple copying in which images are formed by overlapping two or more original images on one side of one sheet S,
The sheet S on which the toner image is formed on the first surface is not discharged outside the machine, but is guided to the branch bus 175 via the flapper 173. First, in the case of double-sided copying, sheet S is 8 character bus 17
6, the paper is discharged onto the intermediate tray 179 by the final discharge roller pair 177. Further, during multiple copying, the paper is discharged from the middle of the figure 8 bus 176 onto the intermediate tray 179 via the deflection members 180 and 181 located in the middle of the figure 8 bus 176. Sheets S stacked on intermediate tray 179
The image is separated from the lower side and fed, and after passing through the paper refeed bus 182, the image is transferred again at the transfer unit 166 for double-sided copying or multiple copying.

The second automatic double-sided configuration is the copying machine P3 shown in FIG.
The basic configuration is a C-shaped bus located in the center.

In the same figure, when performing double-sided/multiple copying, the device with the C-shaped bus configuration forms an image on the first side, similar to the device with the basic configuration of the S-shaped bus described above. The sheet S is transferred to a branch bus 175 via a flapper 173.
be led to.

For double-sided copying, it is necessary to stack the sheets S on the intermediate tray (sheet storage means) 183 with the image surface obtained by the first transfer facing upward, so the sheets S are stacked on the flapper 185.
The paper is once transported to the switchback bus 186 via the switchback bus 186, where it is switched back and then sent to the transport section 187 above the intermediate tray 183. Then, the sheet S is transferred to the conveying section 18
7 predetermined deflection members 189, 190 or the most distal discharge roller 191 onto the conveying section 183. At the time of multiple copying, the sheet S is directly discharged onto the intermediate tray 183 from a predetermined position of the conveying section 187 without sending the sheet S from the flapper 185 to the switchback path 186.

In order to provide an appropriate ejection position depending on the size (length) of the sheet S for both double-sided copying and multiple copying, a deflection plate 189 that allows the ejection position to be switched to multiple locations;
190 is arranged above the intermediate tray 183.

(c) Problems to be solved by the invention However, the copying machine P2 constituting the above-mentioned S-shaped bus
In the case of
The disadvantage is that the size of 2, especially the height dimension, is very large.

Furthermore, due to the long conveyance path, there is a problem that when a jam occurs, there are many locations where jam removal is to be performed, making the jam removal operation time-consuming.

Furthermore, during double-sided copying, the sheet S discharged to the intermediate tray 179 was aligned in the sheet feeding direction by expecting some movement effect from the inclined surface of the intermediate tray 179 and the sheet S's own weight. S to middle tray 17
A loss time occurs after the paper is ejected to 9 and before entering the paper refeeding process. This problem becomes more pronounced as the number of double-sided copies of the sheet S is reduced, and there is a drawback that the productivity of the copying machine P3 is reduced particularly when making a single double-sided copy.

In addition, in the case of the copying machine P3 that enables double-sided copying using a C-shaped path, when ejecting a large size (A3, 84, etc.) sheet S to the intermediate tray 179, the ejection position of the sheet S is inevitably tends to move away from the leading edge stopper position when refeeding. For this reason, due to the stiffness of the ejected sheet S or the curling of the leading edge of the sheet S, the stiffness of the sheet S may be broken or the leading edge may be curled during sheet ejection, causing the sheet S to be stacked on the intermediate tray 183. It contained extremely unstable factors in terms of gender.

Moreover, above the intermediate tray 183, small size (
Deflection plate 189 for discharge bus compatible with A4, 85, etc.
, 190, etc. are protruding, the spacing between the ejection bus and the intermediate tray 183 is such that due to the device configuration, if a transport failure occurs on the ejection path or within the intermediate tray 183, the jam removal performance will be significantly reduced. The problem was that it was getting worse.

Therefore, the present invention provides a carriage unit having a pair of carriage rollers that can freely pinch and discharge the leading edge of a sheet, and is provided with a carriage unit that can freely reciprocate along the intermediate tray, and a plurality of sensors that detect the position of the carriage unit. By installing the carriage unit along the movement path of the carriage unit, sheets can be smoothly ejected to the intermediate tray regardless of the size of the sheet, and when a paper jam occurs, the carriage unit can be moved according to the location of the paper jam. It is an object of the present invention to provide a sheet conveying device that facilitates jam handling by retracting units to corresponding predetermined positions.

(d) Means for Solving the Problems The present invention has been made in view of the above-mentioned circumstances. For example, as shown with reference to FIGS. A seat storage means (183) for temporarily storing the seat (S);
) is provided at a predetermined position on the upstream side of the discharge roller (3) for discharging the sheet, and a pair of carriage rollers (2) for pinching/conveying the sheet (S) discharged from the discharge roller (3).
0, 23) and a carriage unit (1) capable of reciprocating along the sheet storage means (183), to prevent paper jams when conveying sheets to the sheet storage means (183). It is characterized in that the carriage unit (1) is moved to a predetermined position (51) and stopped when a clogging is detected by the clogging detection means (4, 43, 46).

(E) Function Based on the above configuration, the carriage rollers (20, 23) of the carriage unit (1) pinch the sheet (S) discharged from the discharge roller (3), and in this state, the carriage unit (1) Intermediate tray (sheet storage means 183)
It moves to the paper refeeding position at the leading edge and stops. The carriage unit 1 moves in the direction of the discharge roller 3 while discharging the sheet S from the paper refeeding position, and transfers the sheet S to the intermediate tray 183.
Drain to the top.

If a paper jam occurs in the conveyance/ejection path by the carriage unit 1, the carriage unit (1) is stopped by a jam position detection means such as a sensor (4, 46, 47) that turns ON-OFF, and then the carriage unit 1 is stopped. moves to a predetermined position (the position of sensor 51) and stops. As a result, the space above the intermediate tray (183) is reduced, making it easier to handle jams.

It should be noted that the above-mentioned symbols in parentheses are shown for reference to the drawings, and do not similarly limit the structure of the present invention.

(F) Example A first example of the present invention will be described below with reference to FIGS. 1 to 14. Components that are the same as those shown in FIGS. 40 and 41 are designated by the same reference numerals, and their explanations will be omitted.

FIG. 1 shows a copying machine P1 to which the first embodiment of the present invention is applied.
FIG. In Figures 1 to 4, the flag '
On the downstream side of the collar 185, an intermediate tray ejection sensor 4 for detecting the sheet S, a pair of ejection rollers 3, etc. are arranged, and near the downstream side of the ejection roller 3, the sheet S is detected as described below. A carriage unit 1 is provided that holds and conveys the tip. This carriage unit 1 has a frame body 5 consisting of an upper plate 5a and side plates 5b and 5c integrally provided on both sides of the upper plate 5a.
, 5c are each provided with a pair of rotatable rollers 6 on their outer surfaces.

The carriage unit 1 moves in the front-rear direction (
It is movable in the horizontal direction (in the figure). A pair of belts 9 whose ends are connected to the side plates 5b and 5c.
are fixed to shafts 11.12 and pulley pairs 13.15, respectively.
A motor 16 capable of forward and reverse rotation is coupled to the end of the shaft 11, whereby the carriage unit 1 is moved in the direction of arrow 17 or the opposite direction of arrow 19. Ru.

Both ends of the shaft 21 to which the plurality of carriage rollers 20 are fixed are rotatably attached to the side plates 5b, 5c of the frame 5, and the shaft 21 extending from the side plates 5b, 5c
The bases of a pair of support levers 22 are rotatably attached to both ends of the lever 1. A plurality of carriage rollers 23 forming a pair with the carriage roller 20 and a plurality of stiffening rollers 25 located between the carriage rollers 23 and having an outer diameter longer than the outer diameter of the carriage roller 23 are connected to a shaft 26. are fixed to each. Both ends of this shaft 26 pass through long holes 27 formed in the side plates 5b and 5c, respectively, and are attached to long holes (not shown) formed in the free end of the support lever 22, and are attached to the shaft by springs (not shown). 21 side, that is, in a direction in which the carriage roller 23 comes into pressure contact with the carriage roller 20.

The support lever 22 is urged counterclockwise in the figure by a tension spring 29 whose both ends are locked to the side plate 5b and the support lever 22, and the shaft 26 is attached to the rear end of the elongated hole 27 (the left end in the figure). ) is at rest in contact with.

In this state, the carriage roller 23 is in pressure contact with the carriage roller 20 in a vertical position, as shown in FIG.

An actuation lever 30a of a deflection solenoid 30 is connected to the side edge of the support lever 22 opposite to the spring 29. When the deflection solenoid 30 is actuated at the timing described later, the support lever 22 moves around the shaft 21. arrow 31
The shaft 26 rotates clockwise as shown by , and comes to rest with the shaft 26 in contact with the front end (the right end in the figure) of the elongated hole 27 . In this state, the carriage roller 23 slightly revolves in the paper feeding direction (to the right in the figure) while being in pressure contact with the carriage roller 20, as shown in FIG. Due to this revolution of the carriage roller 23, the tangential direction of the contact portion of the carriage roller 20.23, that is, the discharge direction of the sheet S, is slightly downward.

A motor 32 for driving the carriage rollers 20° 23 is fixed to the side plate 5b of the frame 5, and a gear 33 fixed to its output shaft connects a one-way clutch (not shown) to the end of the shaft 21. It is meshed with a gear 35 attached through the connector. An idle gear 36 meshing with the gear 35 is connected to a clutch 39 (a second
(see figure), and an eccentric cam 40 is fixed to the shaft 37. This eccentric cam 40 is in contact with the circumferential surface of an eccentric cam 41 fixed to the end of the shaft 26.

The base of an operating member 42 is attached to the back side of the upper plate 5a of the frame 5, and its free end extends upward from the upper plate 5a. This activates a sensor that will be described later. In addition, the carriage roller 20 of the carriage unit 1
．． Before and after 23, there are roller sensors 43 for detecting the sheet S.
is installed.

In the above configuration, the operation when making zero double-sided copies (n>1) of one document will be described with reference to FIGS. 5 to 8. In FIG. 1, the operation from the end of single-sided copying to sheet 'S until sheet S enters the switchback path 186 is the same as the operation of the conventional C-shaped bus shown in FIG. 41. The sheet S conveyed by the switchback roller 45 from the switchback path 186 is deflected by the flapper 185 and sent to the discharge roller 3 . A HP (home position) intermediate tray discharge sensor 46 is disposed near the discharge roller 3, and an intermediate tray discharge sensor 47 is disposed downstream thereof.

When the carriage unit 1 is in the HP position shown in FIG.
When the intermediate tray ejection sensor 4 is turned ON by the sheet S in the state of ONL, the carriage roller 20 and the carriage roller 23 of the carriage unit 1 move toward the arrow 49.5.
They each rotate in the direction of 0 and hold the sheet S in their mouths. At this time, when the roller sensor 43 in the carriage unit 1 detects the sheet S, the carriage rollers 20, 23 stop rotating, and the carriage unit 1 moves in the sheet ejection direction indicated by the arrow 17 as shown in FIG.

When the carriage unit 1 reaches below the intermediate tray ejection sensor 47 and the operating member 42 turns on the intermediate tray ejection sensor 47, the carriage unit 1 shown in FIG.
The deflection solenoid 30 is turned ON and the support lever 22 is rotated in the direction of the arrow 31. As a result, carriage roller 2
0 and 23 start rotating with the discharge direction of the sheet S slightly downward as shown in FIG.
While ejecting the cartridge, the carriage unit 1 begins to move in the direction of the arrow 19 toward the HP side, as shown in FIG. The carriage unit 1 is provided with a tensioning roller 25 coaxially with the carriage roller 23 as shown in FIGS. 2 and 4, so that the sheet S can be moved only by the carriage unit 1 as shown in FIG. Even during conveyance, the rear end of the sheet S does not sag. In the carriage unit 1, as shown in FIG. 9, the operating member 42 turns the HP sensor 46 ON.

It will stop at the HP shown in the figure.

Now, the return speed of carriage unit 1 is V.

If the discharge speed of the sheet S is V, then the carriage roller 2
0 and 23 rotate at a circumferential speed (V1v). After discharging the sheet S to the intermediate tray 183, the carriage unit 1 receives the next sheet S from the switchback roller 45 at the position of the HP intermediate tray discharging sensor 46, and the carriage unit 1 receives the next sheet S from the switchback roller 45 at the position of the HP intermediate tray discharging sensor 46. The sheets S are sequentially stacked on the intermediate tray 183 by repeating the operation.

Next, the processing operation when a paper jam occurs will be explained.

FIG. 1o shows a state in which a jam occurs at the delivery section of the sheet S to the carriage unit 1. In this state, the discharge roller 3 is ONL and the roller sensor 43 in the carriage unit 1 is 0FFL. In this case, carriage rollers 20, 2 of carriage unit 1
Since the sheet S is not held in the nip part of 3,
As shown in FIG. 11, the carriage unit 1 moves directly toward the through bus sensor 51 disposed downstream of the intermediate tray ejection sensor 47, and when the actuating member 42 turns the through bus sensor 51 ON/OFF. Carriage unit 1 stops.

As shown in FIG. 6, if the sheet S is held between the ejection roller 3 and the carry/straight rollers 20 and 23 of the carriage unit 1, and a paper jam occurs while the carriage unit 1 is moving in the direction of the arrow 17, In this case, the intermediate tray discharge sensor 4 and the roller sensor 43 are in the ON state, and the copying machine main body 151 detects the location where the jam has occurred. Upon this jam detection, the three clutches shown in FIG. 2 are turned on, the motor 32 is instantaneously rotated, the rotation of the gear 35 is transmitted to the eccentric cam 40 via the idle gear 36, and the eccentric cam 40 rotates in the direction of the arrow. be done. Note that when the clutch 39 is in the OFF state, the idle gear 36 and the eccentric cam 40 are not coupled, and the idle gear 36 can rotate arbitrarily with respect to the eccentric cam 40.

When the clutch 39 is turned on, the eccentric cam 40 rotates integrally with the idle gear 36 in the direction of the arrow, so that the convex part of the eccentric cam 40 presses the convex part of the eccentric cam 41 and the shaft 2
6 to the free end side of the support lever 22. By this movement of the support lever 22, the pressing action of the carriage roller 23 against the carriage roller 20 is released, and the carriage unit 1 moves toward the through-pass sensor 51 with the carriage roller 23 released, as shown in FIG. . When the carriage unit 1 is stopped at the position of the through bus sensor 51, that is, in the state shown in FIG. 13, the jammed sheet S is cleared. Note that after the carriage unit 1 turns on the through bus sensor 51, the carriage roller 23 is
0 may be pressed again.

Next, if a paper jam occurs while the sheet S is being held only in the carriage unit 1, the copying machine main body 151 detects that only the roller sensor 43 of the carriage unit 1 is turned on, and Upon detection, the roller pressure of the carriage roller 23 is released, and the carriage unit 1 moves to the HP on the HP intermediate tray ejection sensor 46 side.

It goes without saying that the jam removal method described above does not change depending on the size of the sheet S, and can be applied to sheets S of various sizes.

The relationship between the location where the jam occurs, the location where the carriage unit 1 moves, and the roller pressure operation of the carriage roller 23 in the above jam processing is summarized in FIG. 14. Note that in the figure, symbol a is a position where the HP intermediate tray ejection sensor 46 is turned on, and b is a position where the through-pass sensor 51 is turned on.

FIG. 15 shows an image forming apparatus equipped with a sheet conveying device as a second embodiment of the present invention.

In this embodiment, two carriage units are provided, each of which is movable independently, and the carriage rollers 20 and 23 of the first carriage unit 1 and the
Carriage rollers 57 and 59 of carriage unit 2 of
It can also be rotated independently.

As shown in FIG. 16, the first carriage unit 1 has a belt 9, similar to the carriage unit 1 of the embodiment described above.
Accordingly, the sheet is moved in the sheet ejection direction indicated by an arrow 17 and in the opposite direction. Similarly to the carriage unit 1, the second carriage unit 2 is supported so as to be able to reciprocate in the direction of the arrow 17, and is driven by a belt 56. The belt 56 is wound around a pulley pair 53 driven by a motor (not shown) and a driven pulley pair 55, and the upstream side of the belt 56 is wound around a pulley pair 53 and a driven pulley pair 55.
It is arranged near the downstream side of the belt 9 for the carriage unit 1.

The carriage unit 2 includes a carriage roller 57.
On the nip side of the carriage unit 59, there is a guide rod 2a into which the sheet S from the carriage unit 1 is inserted, and a guide rod 1 which detects the sheet S.
It has a pair of roller sensors 60. In addition, the home position (HP) of the carriage unit 1 is detected.
On the downstream side of the sensor 46, a first carriage unit 1 is provided.
The sensor 61 is turned 0N-OFF by the sensor 61, and the sensor 62.47 is turned 0N-OFF by the second carriage unit 2.
．． 51 etc. are arranged respectively.

In the above configuration, the operation when making n half-size double-sided copies (n>1) of one original will be described first.

The operation until the sheet S enters the switchback path 186 after single-sided copying is completed is the same as in the case of the conventional C-shaped bus shown in FIG. 41, so a description thereof will be omitted.

In FIG. 16, the switchback roller 45 and the discharge reel 3 rotate in the directions of the arrows, the sheet S is sent to the carriage unit 1 side, and the intermediate tray discharge sensor 4
detects the leading edge of sheet S, carriage unit 1
The carriage rollers 20.23 are rotated in the directions of the arrows by the rotation of the motor 32 and grip the leading edge of the sheet S. At this time, the switchback roller 45 rotates together with the carriage roller 20.23.

When the carriage roller sensor 43 in the first carriage unit 1 detects that the leading edge of the sheet S is caught in the nip portion of the carriage roller 20.23, the motor 32 is stopped and the rotation of the carriage roller 20.23 is stopped. Stop. Next, the moving motor 16 in FIG. 2 starts rotating, and the first carriage unit 1 starts moving in the direction of the arrow 17 in FIG. It rotates at the same circumferential speed as the speed. At this time, the second carriage unit 2 is stationary with the sensor 62 in the ONL position.

When the actuating member 42 (see FIG. 3) of the carriage unit 1 moving in the direction of the arrow 17 turns on the sensor 61, a brake (not shown) acts on the motor 16, and the carriage unit 1 moves as shown in FIG. Stand still. In this state, the carriage roller 20 of the first carriage unit 1
．． 23 and the carriage rollers 57 and 59 of the second carriage unit 2 each start rotating and insert the sheet S into the carriage unit 2.

When the sensor 60 detects that the leading edge of the sheet S is caught in the nip portion of the carriage rollers 57 and 59 of the carriage unit 2, the carriage unit 1 moves in the direction of the arrow 19, as shown in FIG. The carriage unit 2 moves at a speed V in each direction of the arrow 17. Further, the sheet S held by the carriage unit 2 also moves at a speed V in the direction of arrow 17.

During the above movement of the carriage unit 2, the carriage rollers 57, 59 of the carriage unit 2 remain stationary and hold the sheet S in their mouths, but the carriage rollers 20, 23 of the carriage unit 1 rotate at a circumferential speed of 2V. At this time, since a one-way clutch (not shown) is interposed in the gear 35 integrated with the carriage roller 20 of the carriage unit 1, there is a slight speed difference, but the rotational speed of the carriage rollers 20 and 23 determines the movement of the sheet S. Even if the speed cannot be kept up, the seat S will not be damaged due to the action of the one-way clutch.

As the carriage unit 2 moves, when the operating member 63 of the carriage unit 2 detects the paper discharge sensor 47 as shown in FIG. 10, the carriage unit 2 stops. In addition, a deflection solenoid (not shown) of the carriage unit 2 (
(corresponding to the deflection solenoid 30 of the carriage unit 1) acts to cause the carriage roller 57 to revolve toward the sheet discharge side as shown in FIG. The sheet S is discharged by rotating in each direction. Carriage unit 2
, while performing the action of discharging the sheet S, returns in the direction of the arrow 19 at a speed V, as shown in FIG.

Further, the discharge speed of the sheet S is V, and the sheet S is stationary relative to the intermediate tray 183 and only falls onto the intermediate tray 183. When the above discharge operation is performed, the carriage rollers 57 and 59 of the carriage unit 2 are rotating at a circumferential speed of 2V. When the carriage unit 2 is discharging the sheet S, the carriage unit 1 moves in the direction of arrow 17 while holding the next sheet S in its mouth. When the sheet S is completely discharged onto the intermediate tray 183, a solenoid (not shown) turns ON, and the feeding roller 65 descends and comes into contact with the sheet S. Next, the deflection solenoid of carriage unit 2 goes to 0FFI.

Then, the carriage roller 59 returns to its original position.

1st. The second carriage unit 1.2 returns to the state shown in FIG. 17, and the sheet S is delivered to the carriage unit 2 again, and the feeding roller 65 moves away from the sheet S on the intermediate tray 183, and the sheet S are stacked on the intermediate tray 183. When the stacking of the sheets S onto the intermediate tray 183 is completed, the stacked sheets are aligned in the lateral direction by a width adjusting motor (not shown). Intermediate tray 18
Regarding the refeeding of sheets from 3, it is similar to the conventional apparatus shown in FIG. The sheets S are separated and conveyed one by one by the second registration roller 70 and the separation roller 66.
The skew of the sheet S is corrected by conveying it while forming a loop between the second registration roller 70 and the separation roller 66.

Next, the processing action when a paper jam occurs during the operation described above will be explained.

1st. The second carriage unit 1.2 is in the state B shown in FIG. 16 or 17 (sensors 4, 43 are ON, sensor 60 is
is OFF), the carriage roller 23 of the first carriage unit l is turned off by the method described in the first embodiment.
When the pressure is released, the carriage unit 1 is moved to a position where the intermediate tray ejection sensor 4 is turned on, and the carriage unit 2 is moved to a position where the through path sensor 51 is turned on.

Further, as shown in FIG. 22, when the sheet S is not caught in the nip portion of the carriage rollers 20 and 23 and a paper jam occurs when the sheet S is delivered to the first carriage unit L (sensor 79 is ON1 sensor 80, 60 is OF
F), as shown in FIG. 23, the carriage unit 1 is moved to the position where the sensor 61 is turned on, and the carriage unit 2 is moved to the position where the sensor 62 is turned on to remove the jammed sheet S. will be carried out.

Furthermore, the state shown in FIG. 18 (sensor 4 is ON, sensor 43,
60 is OFF), if a paper jam occurs,
．． The roller pressures of the carriage rollers 23 and 59 are released for both the second carriage unit 1.2, and the carriage unit 1 is moved toward the HP sensor 46, and the carriage unit 2 is moved toward the through-pass sensor 51, respectively. The ON-OFF state of each sensor and the positional relationship between both carriage units 1.2 at the time of these paper jams are summarized in FIG.
B indicates the position where the sensor 61 is turned on, C the position where the sensor 62 is turned on, and D the position where the sensor 51 is turned on.

Next, the large size sheet S is
The operation when copying sheets (n>1) is shown in FIGS.
This will be explained based on FIG.

When making the above copy, use the second carriage unit 2.
is retracted to a position where the through-pass sensor 51 is turned on. The first carriage unit 1 holds the leading edge of the sheet S at the position of the intermediate tray ejection sensor 4, and the carriage roller 2
Carriage unit 1 with 0.23 rotation stopped
moves in the direction of arrow 17. The carriage unit 1 stops with the sensor 61 turned ON, and the discharge ports of the carriage rollers 20 and 23 are directed slightly downward by the operation of the solenoid 30 shown in FIG. In this state, the carriage roller 20
．． 23 rotate in the directions of the arrows and discharge the sheet S onto the intermediate tray 183.

The carriage unit 1 moves the second sheet while discharging the sheet S.
As shown in FIG. 9, it moves in the direction of arrow 19. In order for the carriage unit 1 to discharge the sheet S at a speed V, assuming that the speed at which the carriage unit 1 moves is V, the carriage rollers 20 and 23 rotate at a speed of 2V. At this time, the next sheet S enters the switchback path 186 and is gripped by the switchback roller 45. Carriage unit 1 returns to the home position and sensor 79
When turning ON, the next sheet S is moved to the carriage roller 20.
23 is put in his mouth.

A case will be described in which a paper jam occurs in the above operation of the carriage unit 1.

As shown in FIG. 25, when the leading edge of the sheet S is not delivered to the carriage unit 1 and a paper jam occurs, the second
As shown in FIG. 6, the carriage unit 1 moves to a position where the sensor 62 is turned on.

The state shown in FIGS. 27 and 28 (sensors 79 and 80 are
When a paper jam occurs in the N state), the roller pressure of the carriage roller 23 of the carriage unit 1 is released, and the carriage unit 1 moves toward the sensor 62 as shown in FIG. State B shown in FIG. 29 (sensor 79 is OFF,
If a paper jam occurs when the sensor 80 is ON (1!1), the roller pressure of the carriage unit 1 is released and the carriage unit 1 moves toward the sensor 79. The operations of the carriage units 1, 2 and sensors 79, 80 described above are collectively shown in FIG.

Next, when making one double-sided copy from one double-sided original for both half size and large size sheet S,
The case where one double-sided copy is made from two single-sided originals will be explained based on FIGS. 31, 32, and 39.

The sheet S is gripped by the carriage rollers 20, 23 of the carriage unit 1 and the carriage rollers 57, 59 of the carriage unit 2 via the switchback path 186 in the same manner as in FIGS. 16 to 18. . The carriage unit 2 moves to a location where the through-pass sensor 51 is turned on as shown in FIG.
During this time, the carriage unit 1 moves in the direction of arrow 17. Carriage roller 57.5 of carriage unit 2
9, the sheet S moves through the through path section 71 (15th
(see figure) between the conveyor rollers 72.

When the leading edge of the sheet S is detected by the sensor 73, the carriage unit 2 moves in the direction indicated by the arrow 19, as shown in FIG.
Return to the direction, and carriage unit 1 will load the next sheet S.
When both carriage units 1 and 2 reach the sheet transfer section, transfer the sheet S from carriage unit 1 to carriage unit 2.
The sheet S discharged from the carriage unit 2 is transferred to a pair of transport rollers 72 and a second roller 69.
It is transported while forming a loop between the two. Intermediate tray 1
83, the sheet S is temporarily in a free state, whereas when passing through the guide rail 7, the sheet S is constantly restrained. One time is enough.

The operations shown in FIGS. 31, 32, and 39 are for the large size sheet S, but in the case of the half size sheet,
In the large size, the operation shown in FIG. 31 is not performed, and the sheet S is sometimes supported only by the carriage unit 2 as shown in FIG. Due to the restraint effect on S,
The rear end of the sheet S hardly sags.

Next, a case where a paper jam occurs during the operation when the sheet S passes through the through path section 71 will be described.

As shown in FIG. 34, when the sheet S is delivered to the carriage unit 1, and as shown in FIG. 30, when the carriage unit 1 conveys the sheet S, the intermediate tray 1
Since the operation is the same as that for stacking sheets S on 83, jamming of sheets S is also performed in the same process.

When both carriage units 1.2 are in state B in Fig. 31 (large size transport, sensors 80, 81 are ON, sensors 79, 82 are OFF), carriage unit 2 releases the roller pressure. through-pass sensor 51
The carriage unit 1 stops at the ONL position, releases the roller pressure, and moves to the position where the HP sensor 46 is turned ON. In this way, various jam occurrence positions and corresponding movement locations of the carriage unit 1.2 are explained.
The case of large size is shown in FIG. 36, and the case of small size is shown in FIG. 37.

In the embodiment described above, the intermediate tray 1 of the copying machine main body 151
Although the case where the present invention is applied to No. 83 has been described, similar effects can be obtained when the present invention is applied to a circulation type document conveying device.

Here, a case will be described in which the present invention is applied to a circulating document feeder (hereinafter referred to as RDF).

FIG. 38 shows a longitudinal side view of the RDF. In the figure, a document 101 is placed on a document tray 102 with the document surface facing upward, and the document 101 is fed into the separating section B from the bottom by a half-moon roller 103 and a weight 105. The separation section B includes a separation belt 10
6 and a feeding roller 107, which separates the bottom sheet.

The separated document 101 enters the path 110 and hits a pair of registration rollers 109, forms a predetermined loop, and is then conveyed by the pair of registration rollers 109 to a platen 117 on the main body side. Drive roller 113 and driven roller 112
A belt 111 wound around the belt 111 is disposed facing the platen 117, and the belt 111 is pressed against the platen 117 by a plurality of press rollers 115.

Document 1 sent between platen 117 and belt 111
01 is conveyed to a predetermined position at the end of the platen 117 (the left end in FIG. 38) by the movement of the belt 111, and then stopped.

Here, the original 101 is read by a reading means such as an optical system of the main body of the copying machine (not shown). When the predetermined reading of the original 101 is completed, the belt 111 moves again to feed one original 101 into the path 119.
01 is held in the large roller 120 and reversed, and the first
The document is transferred from the second carriage unit 121 to the second carriage unit 122, and is set on top of the stacked documents 101 with the document surface facing downward. Hereinafter, the same operation as above is performed for the remaining document 101,
One copy of the plurality of originals 101 is completed.

Note that bus 123 is a bus for reversing double-sided originals, and reference numeral 125 is a switching flapper thereof, which is not directly related to the present invention.

The first carriage unit 121 and the second carriage unit 122 are the carriage unit 1 described above.
, 2, and can transport the document 101 between the roller pairs, while being guided by a long hole 126 formed in the side plate of the RDF and moving in the forward and reverse directions shown by the arrows. It is possible. The first carriage unit 121 and the second carriage unit 122 make it possible to transport and discharge the original 101 while holding the original 101 between them.

The detailed operation of these carriage units 121 and 122 is the same as the operation of the intermediate tray 183 in the above-described embodiment, so that the RDF jam handling performance can be improved in the same way as in the copying machine P1. can.

As explained above, according to the above-described embodiment, the mechanism for conveying the sheet is constituted by the carriage unit 1 (2) that can reciprocate above the intermediate tray 183. When a jam occurs, the jam signal of the copying machine main body 151 and the sensors 4, 4
6.47 etc., the jam state of the sheet S is inferred, and the carriage unit 1 is moved to a corresponding position (for example, the position of the sensor 46 or 51) and stands by. , the upper part of the intermediate tray 183 is opened, allowing the user to easily process jammed sheets.

In addition, since the carriage unit 1 is configured to be able to be positioned at any position on the intermediate tray 183, the ejection position from the carriage unit 1 to the intermediate tray 183 can be adjusted to multiple positions in response to changes in the size of the sheet S, for example. This can be implemented without providing a deflecting means, and the device can be made smaller.

Furthermore, in terms of sheet stackability, for example, by controlling the discharge speed of the carriage rollers 20 and 23 in the carriage unit 1, it is possible to transport the carriage unit 1 in the opposite direction while the sheet S is being discharged.

Thereby, regardless of the size (length) of the sheet S, it is possible to bring the discharge position from the carriage unit 1 to the intermediate tray 183 as close as possible to the paper refeeding entrance.

Therefore, it is possible to suppress the degree of freedom of the leading edge of the sheet while it reaches the paper refeeding entrance, and in particular, it is possible to prevent loading failures due to stiffness when loading large size (weak H) sheets S. At the same time, during double-sided copying, it is possible to prevent the sheet from getting caught between the leading edge of the next stacked sheet S and the toner state on the image surface of the already stacked sheets.

Furthermore, in the conventional stationary discharge path, it was not possible to change the sheet discharge action in response to information on the number of sheets S discharged to the intermediate tray 183. Therefore, when performing double-sided copying of a large number of sheets, the ejection conditions of the sheet S vary as the level of the topmost sheet stacking surface of the already stacked sheets changes, making it difficult to obtain stable stacking from a small number of sheets to a large number of sheets. However, in the configuration of this embodiment, the ejection position of the carriage unit 1 can be moved minutely in accordance with the sheet number information (physical characteristics of the sheets), and the carriage roller in the carriage unit 1 can be moved. It becomes possible to change the angle of 20.23 in accordance with the sheet number information (physical properties of the sheet), and it is possible to stably supply the sheets S into the intermediate tray 183 from the appropriate ejection position and ejection angle. becomes. This allows the sheet S
The loading performance on the intermediate tray 183 is improved.

Furthermore, noises such as sudden mechanical sounds in the sheet conveyance/loading configuration device of the conventional stationary discharge bus and noises such as the rubbing noise between the guide plate and the leading edge of the sheets can be avoided by using the carriage unit conveyance/loading mechanism of this embodiment. By adopting this method, it will be dramatically reduced.

(G) As described in detail, according to the present invention, a carriage unit capable of reciprocating is attached to a sheet conveyance bus/discharge bus to an intermediate tray (sheet storage means) provided in the middle of a sheet conveyance path. is provided, and when a paper jam occurs, the carriage unit is moved to a position where it is easy to clear the jam according to the location where the paper jam occurs, thereby improving jam clearing performance.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view of an image forming apparatus to which a first embodiment of the sheet conveying device of the present invention is applied, FIG. 2 is a front view of the carriage unit of the present invention, and the third section is a perspective view as well. Figure 4 is an enlarged perspective view of the main parts, Figures 5 to 9 are operation diagrams during sheet conveyance, Figures 10 to 13 are operation diagrams of sheet jam removal, and Figure 14 is the location where the jam occurs. FIG. 15 is a longitudinal cross-sectional side view of a sheet conveying device showing a second embodiment of the present invention, and FIG.
Figures 2 to 20 are half-size sheet conveyance operation diagrams,
Figures 1 to 23 and 24 are relationship diagrams showing jam occurrence positions and carriage movement locations, Figures 25 and 26 are diagrams of jam removal operations for half-size sheets, and Figures 27 to 30.
The figure is a diagram of the jam processing operation for large size sheets, Figures 31 to 33, and 39 are diagrams of the operation when the sheet passes through the through bath, Figure 34 is the jam operation diagram, and Figures 35 to 37 are the jam occurrence diagrams. FIG. 38 is a longitudinal cross-sectional side view of the circulation type document conveyance device to which the present invention is applied, FIG. 39 is a diagram of its operation, and FIG. 40 is a diagram showing the relationship between the position and the carriage movement location. A vertical side view of an image forming apparatus of
FIG. 41 is a longitudinal sectional side view of a conventional image forming apparatus having a C-shaped sheet conveying device, and FIG.
FIG. 2 is a block diagram of emission restriction. S...Sheet, P3...Copying machine (image forming apparatus), 1...First carriage unit, 2...Second carriage unit, 3...Ejection roller, 4...Intermediate Tray discharge sensor, 20.23... Carriage roller, 39... Clutch (release means), 40.41... Eccentric cam (release means), 43.60
... Carriage roller sensor, 46.47,51,
61.62... Carriage position detection sensor, 183... Intermediate tray (sheet storage means).

Claims (1)

[Scope of Claims] 1. A sheet storage means provided in the middle of a sheet conveyance path to temporarily store sheets; and a discharge roller provided at a predetermined position on the upstream side of the sheet storage means to eject the sheets. and a carriage unit that includes a pair of carriage rollers that pinches and conveys the sheet discharged from the discharge roller, and is capable of reciprocating along the sheet storage means, and that conveys the sheet to the sheet storage means. A sheet conveying device, characterized in that the carriage unit is moved to a predetermined position and stopped when a paper jam is detected by a paper jam detection means. 2. The sheet conveying device according to claim 1, wherein the carriage unit changes a stopping position depending on a location where a paper jam occurs, which is detected by a paper jam detection means. 3. The sheet conveying device according to claim 1, wherein the carriage roller has a release means for releasing the pressure when a paper jam is detected.