JPH032530Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a paper feeding device for a copying machine, and more specifically, it has an automatic paper feeding device, and after one-sided copying, the copy paper is turned over and returned to the automatic paper feeding device section. The present invention relates to a paper feeding device for a copying machine that uses this automatic paper feeding device again to feed copy paper into the machine to perform double-sided copying.

BACKGROUND ART Conventionally, various methods and devices have been proposed or provided for obtaining copied images on both sides of a sheet of copy paper. For example, as shown in Japanese Patent Application Laid-Open No. 49-96734, copy paper is automatically fed from the paper feeder, turned over after copying is completed, and then fed back into the paper feeder to activate the automatic paper feed mechanism. There is a device that uses this to feed the back side for copying. Although this method has the drawbacks of time loss and many restrictions on use because it performs double-sided copying on a single sheet, it does require an intermediate tray to store the copied sheets and an accompanying feeding mechanism. etc. without the need for
In particular, it has the advantage of being a simple double-sided copying mechanism in small-sized copying machines.

On the other hand, with this type of duplex copying mechanism, the automatic paper feeding mechanism is used to feed copy paper during back side copying, so the copy paper feeding start position during back side copying is set to the initial automatic feeding position. A mechanism is required to substantially match the paper starting position. Specifically, the above-mentioned JP-A-Sho
As shown in No. 49-96734, the paper feed roller is
The paper feed roller can move toward and away from the top surface of the stacked copy paper, and with the paper feed roller separated from the top surface of the copy paper, the copy paper after single-sided copying is fed between the paper feed roller and the stacked copy paper, and the top and bottom The structure is such that the leading edge of the copy sheet is positioned by a movable stopper.

However, this stopper must be configured so that it protrudes from the top surface of the laminated copy paper only when necessary, and is normally retracted downward, so as not to interfere with the feeding of the laminated copy paper, which makes the mechanism complicated. The advantages of the above-mentioned simple double-sided copying mechanism were lost.

Purpose The present invention was developed with attention to these points, and by using a flexible member as a stopper, it is possible to make copies after one-sided copying without using a complicated structure such as a stopper retraction mechanism. In addition to efficiently positioning paper or manually fed copy paper, the flexible stopper is placed in a position where the leading edge of the fed paper does not touch when feeding laminated paper, thereby preventing paper jams and feeding. It is an object of the present invention to provide a paper feeding device that solves problems such as uneven paper timing.

Example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing an example of a copying machine 100 that is equipped with a paper feeding device according to the present invention and is capable of automatic double-sided copying. First, the configuration and operation of the copying machine 100 will be briefly explained with reference to this diagram.

A photoreceptor drum 10 is supported at approximately the center of the main body of the copying machine so as to be rotatable in the counterclockwise direction in the figure, and around it are a charging charger 11, a projection optical system 12 such as a lens array, and a developing device 13. , a transfer charger 14, a blade type cleaning device 15, and an illumination device 1 that serves as an eraser and document illumination.
The photosensitive drum 10 is charged, exposed, and developed as it rotates, and a visible image is formed on its surface by toner. The toner image is transferred onto the conveyed copy paper P by the transfer charger 14. After the image has been fixed on the copy paper P by the fixing device 17, the image is fixed on the copy paper P after the transfer, and then it is transferred to the tray device 2 by a pair of discharge rollers 18.
The photoreceptor drum 10 is then removed from the toner and charge remaining on its surface by a cleaning device 15 and an illumination device 16, and is ready for the next copying operation.

Copying machine 100 also includes document transport device 30 . In the document conveyance device 30, the document inserted along the table 31 is detected by a sensor S1 such as a photoelectric element.
When detected by the copier 10, the copying machine 10
0 and the document conveying device 30 are started, and the document is fed into the machine by the conveying rollers 32 and 33. When the conveyed document passes over a transparent plate 34 provided in the illumination section, it is projected onto the photoreceptor drum 10 via the optical system 12, and is then gripped by conveyance rollers 35 and 36, and then transferred to the first conveyance stage. When the switching guide 37 is in the position indicated by the solid line in the figure, arrow a
When the guide 37 is in the position indicated by the dashed line in the figure, the paper is reversely conveyed upward along the guide plate 38, and is conveyed face down in the direction of the conveyance rollers 32, 40 by the conveyance rollers 35, 39. It will be sent back. The original that has passed through the transport rollers 32 and 40 is transferred to the second switching guide 41, which is set to the position indicated by the dashed-dotted line in the figure, if the control mode of the copying machine is double-sided copying mode.
The paper is carried out in the direction of arrow b along the upper surface of the paper, and is discharged onto the table 31, and due to its inclination, is sent between the transport rollers 32 and 33 from the rear end side. On the other hand, if the control mode is a so-called multi-copy mode in which a plurality of copies are made successively from one original, the second switching guide 41 is set to the solid line position in the figure, whereby the original is again reversely conveyed along the rollers 32 and sent between the conveying rollers 32 and 33 with the same side facing down as the first time.

Next, the paper feeding device 50 and tray device 20 of the copying machine 100 will be explained with reference to FIGS. 2 to 9.

In the paper feeding device 50, the copy paper P is placed in a shaft 53 in a cassette main body 51 which is removably attached to the copy paper.
The cassettes are stacked and held on a mounting plate 53 that is swingably provided around a, and are pushed upward by a spring 52 that is provided between the mounting plate 53 and the bottom of the cassette body 51. . On the other hand, corner separators 54 are provided on both side walls of the cassette main body 51.
is swingably supported by a shaft 54a,
The support portion 54b is prevented from rotating upward by coming into contact with stoppers 55 provided on the inner surfaces of both side walls of the cassette body 51. Since the corner separator 54 comes into contact with both corners of the top surface of the copy paper P, the upward movement by the spring 52 is prevented by the support portion 54b of the corner separator 54 coming into contact with the stopper 55. Therefore, regardless of the remaining amount of stacked copy paper P, the position of the topmost paper is kept constant.

The paper feed roller 56 has a substantially semicircular shape as shown, and its rotation shaft 56a is connected to a drive mechanism via a one-turn clutch (not shown), and the shaft 56a is rotated by an appropriate paper feed signal. Then, the paper feed roller 56 contacts the top surface of the copy paper P held by the corner separator 54, feeds out a predetermined amount of the top copy paper, rotates once, and reaches the position shown in FIGS. Stop. Therefore, the paper feed roller 56 is separated from the upper surface of the stacked copy paper P when stopped. The rotation of the paper feed roller 56 is started, for example, when the sensor S1 of the document conveyance device 30 detects the leading edge of the document.

At the timing when the paper feed roller 56 starts rotating, the timing rollers 57 are in a state separated from each other as shown by the dashed line in FIG. The position of the tip is regulated by contact. Next, when the leading edge of the document conveyed by the document conveyance device 30 is detected by the sensor S2 (see FIG. 1), the timing roller 57 is pressed and the stopper 61 is driven by an appropriate drive mechanism. The copy paper P is then evacuated from the paper path, and the copy paper P is transported in synchronization with the transport of the original document.

The copy paper P that has been conveyed and has undergone the transfer and fixing processes as described above is delivered by a discharge roller 18 to a tray device 20 consisting of a fixed tray 21 and a movable tray 22.
In the double-sided copy mode, the movable tray 22 is lifted to the position shown by the solid line in the figure, and the copy paper P is guided along the lower surface of the movable tray 22, and the copy paper P is ejected from the fixed tray 21. and the cover 58 on the upper surface of the cassette. When the copy paper P is finished being ejected, it slides down from the rear end side along the cover 58 and then slides down to the ejection roller 18.
The paper feed roller 5 moves forward while lightly touching the lower roller 18a of the paper feed roller 5, and stops after moving away from the top surface of the laminated copy paper.
6, and comes into contact with a stopper 60 and stops.

As shown in FIG. 3, the stopper 60 is a thin piece of plastic film or the like fixed to the edge alignment part 54c of the corner separator 54 by adhesive or the like. The paper feed roller 5 has sufficient strength to stop the copy paper, and the copy paper that has been stopped or the copy paper that is stacked is
6, it has enough flexibility to not interfere with its conveyance. Note that when the stacked and held copy sheets are sent out by the paper feed roller 56, the leading edge of the copy paper between the paper feed roller 56 and the corner separator 54 forms a loop, and a stopper 60 is provided at the position shown in the figure. If it is, there will be no hindrance to its delivery. Specifically, the stopper 60 is made of Mylar (trademark of DuPont) with a thickness of about 0.1 mm, or a thin metal piece of stainless steel or phosphor bronze with a thickness of 0.1 mm or less. Furthermore, the stopper is shown as 60' in FIG.
It may be provided on the upper surface of the guide plate 62 which also serves to regulate the mounting position of the cassette main body 51.

In this way, by using a flexible thin piece as described above as a stopper for stopping the copy paper at the paper feed unit after single-sided copying, double-sided copying can be performed with a simple structure without the need for a complicated evacuation mechanism. Paper feeding can be achieved.

Note that S3 is a sensor for detecting copy paper, which detects the return of copy paper after single-sided copying in double-sided copy mode or the insertion of copy paper in manual paper feed mode, which will be described later, and controls the drive of the ejection roller 18 and transports the original. Performs synchronization control with the device 30, etc.

A switching mechanism for the movable tray 22 in the tray device 20 is shown in FIGS. 5 to 7. Movable tray 22
is swingably supported by a pin 22a on the side plate of the main body of the tray device, and its swinging due to its own weight is prevented by a bent portion 23a of the lever 23. The lever 23 is rotatably fitted to the shaft 24, and its rotation due to its own weight is caused by the clutch drum 25.
This is prevented by push-up rollers 25a provided in the. The clutch drum 25 is connected to the drive shaft 25
The shaft 25b is rotatably fitted to the shaft 25b.
and a one-way clutch mechanism such as a clutch spring (not shown). Springs 26 and 27 are located near the clutch drum 25.
Levers 28 and 29 are rotatably provided, each having a counterclockwise rotational habit. The levers 28 and 29 each have a claw portion 28
a, 29a and engaging parts 28b, 29b, and the lever 28 is a solenoid.
Connected to SL.

In the above configuration, the spring 26 is given a stronger force than the spring 27, and when the solenoid SL is off, the claw portion 28a of the lever 28 is pressed against the clutch drum 25 as shown in FIG. The portion 28b is the engaging portion 2 of the lever 29.
9b is pushed up and its claw portion 29a is retracted from the clutch drum 25. Then, the claw portion 28a of the lever 28 falls into a notch 25c provided near the roller 25a on the periphery of the clutch drum 25 and engages with the ratchet 25d, and the clutch drum 25 is locked with the roller 25a positioned downward. has been done. In the duplex copying mode, when the solenoid SL is turned on at an appropriate timing, the pawl 28a of the lever 28 separates from the ratchet 25d and the clutch is engaged, and the clutch drum 25 starts rotating counterclockwise in the figure and the lever is closed. 29 claw portion 29a
comes into contact with the circumferential surface of the drum 25. As the drum 25 rotates, the roller 25a moves upward while pushing up the lever 23, and as shown in FIG.
The claw portion 29a falls into the notch 25c of the drum 25 and stops at the position where it engages with the ratchet 25d. This state is a state in which the movable tray 22 is lifted upward, as shown by solid lines in FIGS. 1 and 2.

When solenoid SL is turned off again, lever 2
The claw portion 29a of the lever 28 is pressed against the peripheral surface of the drum 25, so the drum 25 rotates, the movable tray 22 descends, and the claw portion 28a falls into the notch 25c. By the way, the drum 25 is stopped.

Although the tray device 20 has the above-described configuration, it is also possible to manually feed copy paper using the slit portion 20a formed between the movable tray 22 and the fixed tray 21. can.

As shown in FIGS. 1, 2, and 8, the movable tray 22 is located slightly above the fixed tray 21, and a slit portion 20a is formed between the two to allow manual insertion of copy paper. When the copy paper inserted from the slit section 20a is detected by the sensor S3, at least the discharge roller 18 is rotated thereby to advance the copy paper to the stopper 60 section. Therefore, even if the distance from the slit portion 20a to the stopper 60, which is the stopping position, is long, no inconvenience occurs because the roller 18a advances the copy paper. Further, since the roller 18a only lightly touches the copy paper and advances the copy paper, the stopper 60
The copy paper that comes into contact with will stop at that position. Also,
If a convex guide is formed at a predetermined reference position on the upper surface of the cover 58 and the lower ejection roller 18a is given a conveying behavior that causes the copy paper to follow this guide, skew feeding will not occur.

If a document is inserted along the table 31 into the manually inserted copy sheet and stopped at the stopper 60, the same copying operation as in the case of automatic sheet feeding described above can be performed.

On the top surface of the fixed tray 21, there is a guide 2 that indicates the reference position for inserting paper in order to facilitate manual feeding operation.
1a may be provided. This guide 21a can also be made movable depending on the paper width.

FIG. 9 shows a tray device 20' having no moving parts.
shows. In this case as well, the tray bottom plate 21' is provided with a slit-shaped opening 20'a, so that it can be configured to serve both as an ejection tray and a manual feeding table. Further, at this time, the tray bottom plate 21' has a level difference in front and back of the slit-shaped opening 20'a in the direction of manual insertion so that the front side is lower, so that the manual insertion operation is facilitated.

Effects As explained above, the present invention includes a paper feed roller that is provided so as to be able to approach and separate from the sheets held in a stack in a paper feed section, and a roller that presses both corners of the top surface of the leading edge of the sheets that are held in a stack. a claw member that bends the topmost sheet of paper in a loop shape and separates it from other sheets when the topmost sheet of the arranged and stacked sheets is sent out by a paper feed roller; the paper feed roller and the stack holding member; a paper feeding mechanism that feeds the paper between the pawl member disposed on the top surface of the paper, and a paper feeding mechanism that is fixedly provided so as to protrude from the top surface of the paper near the pawl member and that is fed by the paper feeding mechanism; and a flexible stopper member for stopping the paper being held in a stack, and the flexible stopper member is configured to loop with the claw member so that the paper passes over the stacked paper when the paper is fed by the paper feed roller. The paper is placed at a position where the leading edge of the uppermost sheet of paper that has been shaped like a sheet does not come into contact with it, and is fed out when the sheet fed onto the claw member by the sheet feeding mechanism is fed by the sheet feeding roller. Since this is a paper feeding device that is deflected and retracted by the paper that is inserted, when applied to a double-sided copying machine, etc., it is possible to feed paper after single-sided copying or manually fed paper by using a simple configuration. It is possible to make the paper feeding start position approximately coincide with the first stacked paper feeding start position, and to feed the paper using the same paper feed roller as the stacked and held paper, and also to feed the stacked paper. When paper is separated, a fixed flexible stopper member is placed at a position where the leading edge of the fed paper does not come into contact with it, so that the leading edge of the paper does not come into contact with the flexible stopper when the paper is separated by the separating claw. This has the advantage of being able to prevent problems such as paper jams and uneven paper feeding timing that occur due to this.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing the configuration of a copying machine equipped with the paper feeding device of the present invention, Fig. 2 is a view showing the paper feeding device section, Fig. 3 is a perspective view of the main part, and Fig. 4 shows the stopper. 5 is a perspective view showing the movable tray drive mechanism of the tray device, FIGS. 6 and 7 are explanatory diagrams of its operation, and FIG. 8 is a perspective view of the main parts of the tray device. FIG. 9 is a diagram showing another embodiment. 50... Paper feeding device, 54... Corner separator, 56... Paper feeding roller, 60, 60'... Stopper, 62... Guide plate, 18... Ejection roller,
18a...roller (paper feeding mechanism), 20...tray device, 20a...slit portion, 21...fixed tray, 22...movable tray.

Claims (1)

[Claims for Utility Model Registration] A paper feed roller that is movable toward and away from sheets held in a stack in a paper feed section; and arranged to press both corners of the top surface of the leading edge of the sheets held in a stack; a claw member that bends the topmost sheet of paper in a loop shape and separates it from other sheets when the topmost sheet of the sheets held in a stack is sent out by a paper feed roller; the paper feed roller and the paper held in a stack; a paper feeding mechanism that feeds the paper between the claw members disposed on the upper surface; and a paper feeding mechanism that is fixed so as to protrude from the upper surface of the paper near the claw members and that feeds the paper by the paper feeding mechanism. a flexible stopper member for stopping the flexible stopper member, and the flexible stopper member is formed into a loop shape by the claw member so that the paper passes over the stacked paper when the paper is fed by the paper feed roller. The leading edge of the uppermost sheet of paper is placed in a position where it does not abut, and when the paper fed onto the claw member by the paper feeding mechanism is fed by the paper feed roller, the paper that is fed out is A paper feeding device characterized by being bent and retracted.