JPH0192171A - Image forming device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of jamming by a thick sheet of paper, etc., by closing a manual feeding port by means of a sheet material discharging tray at the time of selecting a discharging direction having a curved part with a smaller radius in a sheet material discharging course. CONSTITUTION:At the time of feeding a sheet material S from a cassette 8, as a discharging tray 22 is set to a downwardly revolved position 22', the sheet material S is discharged onto the lower inner face 22a of the discharging tray 22 through a sensitive drum 2, a transfer device 6, and a fixing device 17. In this condition, a manual feed tray 12 is opened and a relatively thick sheet of paper is discharged nearly linearly onto the paper discharging tray 22'. On the other hand, as the discharging tray 22 is set to an upper position, the sheet material S from the cassette 8 is discharged onto a discharging tray 21 through a curved conveying passage with a smaller radius by means of discharging rollers 19 and, at this time, the front of the manual feed tray 12 is closed prohibiting manual paper feeding. Thereby, the occurrence of jam caused by the manual feeding of a thick sheet material can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Object of the Invention [Field of Industrial Application] The present invention relates to an image forming apparatus such as a laser beam printer, an electrophotographic copying machine, or a printing machine.

[Conventional technology]

In this type of image forming apparatus, sheet materials of a predetermined size such as print paper, copy paper, printing paper, etc. are stacked and stored in a cassette, etc., and loaded into the main body of the apparatus, and the sheets are automatically delivered by a feeding roller or the like. It is known to have an automatic sheet material feeding means for manually feeding a sheet material and a manual feeding means for manually feeding a sheet material of an arbitrary size from a manual feeding port.

[Problem that the invention seeks to solve]

However, when manually feeding, thick sheet materials such as cardboard or -M cylinders are often used, and if there is a sharp curve in the sheet material conveyance path (sheet path) in the device, thick sheets may Materials may not be transported smoothly. Generally, when conveying a sheet material along a sheet material conveyance path that has a curved part, the thickness of the sheet material that can be transported smoothly is approximately proportional to the radius of the curved part, and if there is a curved part with a small radius, jams may occur. It's easy to do.

In particular, in an image forming apparatus that is capable of selectively discharging a sheet material on which an image has been formed in different discharging directions, the sheet material discharging path in at least one of the discharging directions necessarily has a radius. Therefore, if a discharge direction having a small radius curved portion is selected, there is a problem that jams are likely to occur.

The present invention aims to solve the above problems.

1. Structure of the Invention [Means for Solving Problems] The present invention provides a sheet material automatic feeding means for automatically feeding sheet materials, and a sheet material manual feeder for manually feeding sheet materials from a manual feeding port. It has a feeding means and a sheet material discharge tray that can be opened and closed with respect to the apparatus main body, and is configured to selectively discharge sheet materials in different directions depending on the opening/closing position of the sheet material discharge tray with respect to the apparatus main body. Further, when a sheet material discharging direction having a small curved portion is selected for the sheet material discharging path in each sheet material discharging direction, the sheet material manual feeding port is closed by the sheet material discharging tray. shall be.

[For production]

As described above, when the sheet material discharge path has a curved portion with a small radius, the sheet material manual feed port is closed by the sheet material discharge tray, so that cardboard, etc. It is possible to prevent jams during conveyance.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings in which the present invention is applied to a transfer type laser beam printer.

FIG. 1 is a longitudinal sectional view of a laser beam printer showing an embodiment of the present invention, and FIG. 2 is an enlarged view of a portion thereof.

In the figure, 1 is the main body of the apparatus, 2 is a photosensitive drum as an image carrier disposed inside the main body 1, and around the drum 2 is a charger 3 and a laser scanner unit as an image information writing device)4. Known image forming process equipment such as a developer 2B5, a transfer charger 6, and a cleaner 7 are provided.

Reference numeral 8 denotes a sheet material feeding cassette detachably provided at the end of the apparatus main body 1, and sheet materials S of a predetermined size are loaded and stored in the cassette 8. 9 is the cassette 8
The sheet material S fed out by the roller 9 is guided between a pair of registration rollers 11 through a sheet path 10.

On the other hand, 12 is a manual feeding tray for sheet materials, 13 is a guide member, and 14 is a manual feeding roller. By inserting between the manual feed rollers 14 along the upper surface of the feed tray 12 from A, the roller 1
The configuration is such that the sheet material is guided between the registration roller pairs 11 and 11 through the sheet path 15 with rotations of 4 and 14 times.

16 and 18 are sheet paths, 17 is a fixing device, 21 is a first discharge tray for discharging the sheet material that has passed through the fixing device 17, and 22 is a second discharge tray. The second ejection tray 22 can be opened and closed with respect to the apparatus main body l around a support shaft 23, and by opening and closing the ejection tray 22 with respect to the apparatus main body l, the manual feeding port A is opened and closed. Ru.

19 is a discharge roller provided integrally with the second discharge tray 22, and 20 is a guide member.

In the above configuration, when performing image formation by feeding the sheet material S from the cassette 8, the photosensitive drum 2 moves in the direction of arrow a in the figure based on an image formation start signal from an operation switch etc. not shown in the figure. After rotating at a predetermined circumferential speed and being uniformly charged by the charger 3, the scanner unit 4 scans the laser beam to form an electrostatic latent image corresponding to desired image information on the photosensitive drum surface. 6 Next, the electrostatic latent image is developed by a developing device 5, and a developed image to be transferred onto a sheet material such as transfer paper is formed on the surface of the photosensitive drum.

At the same time, the sheet material S is sent out one by one from the cassette 8 by the feeding roller 9, and guided between the registration roller pair 11-11 via the sheet path IO. 11@11, the photosensitive drum 2 is synchronized with the rotation of the photosensitive drum 2.
and a transfer charger 6 at a predetermined timing, and the developed image on the photosensitive drum 2 is transferred by the transfer charger 6. The sheet material on which the image has been transferred is then guided to a fixing device 17 via a sheet path 16, fixed, and then fed into a sheet path 18. When the second ejection tray 22 is in the upright position shown by the solid line in FIGS. 1 and 2, the sheet material is curved upward along the lower inner surface 22a of the ejection tray 22, and
The image is discharged onto the discharge tray 21 in a so-called face-down state, with the image side facing downward. Furthermore, when the second discharge tray 22 is at the substantially horizontal position 22' shown by the dashed line in the figure,
The sheet material is conveyed straight in a substantially horizontal direction from the sheet path 18, passes through a discharge roller 19, and is discharged onto a second discharge tray 22 in a so-called face-up state with the image surface facing upward.

On the other hand, when performing image formation by manually feeding the sheet material, the second ejection tray 22 is moved to the position 22' indicated by the chain line in FIGS.
When the sheet material is inserted from the manual feed port A along the manual feed tray 12 between the manual feed rollers 14. The insertion of the sheet material is detected by a sensor or the like not shown in FIG. 1, and the photosensitive drum 2 is rotated based on the detection signal, and a developed image is formed on the photosensitive drum in the same process as described above. At the same time, manual feed roller 1
4 and 14 rotate, and the sheet material is guided between the pair of registration rollers 11 and 11 through the sheet path 15.Then, the pair of registration rollers 11 and 11 transfer charge to the photosensitive drum 2 at a predetermined timing in the same manner as described above. A sheet material is fed between the sheet material and the developing image, and the developed image is transferred thereto and then fixed in the fixing device 17. Then, the ejection roller 1 is moved from the sheet path 18 to the second ejection tray 22' ball located at the chain line position in Figures 1 and 2.
9, the sheet material is discharged in a substantially straight line.

As described above, in the above embodiment, when the sheet material is fed from the tray 8, the second discharge tray 22 is
・The sheet material placed at the solid line position in FIG.
There are two methods: a method in which the sheet material is discharged upwardly, and a method in which the second discharge tray 22 is arranged at the chain line position 22' in the figure and the sheet material that has passed through the fixing device 17 is discharged onto the discharge tray 22' in a substantially straight line. While it is possible to select the method, when manually feeding the sheet material, it is only possible to place the second output tray 22 at the position indicated by the chain line in Figures 1 and 2 and open the manual feeding port A. Manual feeding is possible, and the sheet material that has passed through the fixing device 17 is inevitably transferred to the second output tray 22' located at the chain line position in the figure.
It will be discharged upward in a straight line. Therefore, even when cardboard or the like is manually fed, it can be smoothly conveyed and discharged, and the occurrence of jams and the like can be significantly reduced.

In the above embodiment, when the second ejection tray 22 is placed at the solid line position in Figures 1 and 2, the first ejection tray 21
Although the sheet material is ejected upward, it is also possible to eject the sheet material onto the outer surface 22b of the second ejection tray 22 in the solid line state in the figure. That is, when the second ejection tray 22 is placed at the solid line position in the figure, it is placed on the outer surface 22b of the tray 22, and when the second ejection tray 22 is placed at the chain line position 22' in the figure, it is placed on the outer surface 22b of the tray 22. By configuring the sheet material to be discharged onto the opposite surface 22a, the first discharge tray 21 can be omitted.

FIG. 3 shows a modification of the sheet material manual feed tray 12, in which the manual feed tray 12 has a tray 12a fixed to the radical body 1, and a shaft 24 centered on the fixed tray 12a. It is composed of a movable tray 12b attached so as to be openable and closable. Reference numeral 25 denotes a spring that always biases the movable tray 12b to rotate in the opening direction.

When in use, when the second ejection tray 22 is opened in the direction of the arrow from the state shown in FIG.
is rotated clockwise around the shaft 24 in the figure, and is positioned and held on the extension line of the fixed tray 12a as shown by the chain line in FIG.
When not in use, by closing the second discharge tray 22 to the state shown by the solid line in the figure, the movable tray 12b is pushed by the inner surface 22a of the discharge tray and moves against the spring 25 to the state shown by the solid line in the figure. The device can be returned to its original state and stored within the device body, allowing the device to be made more compact.

In FIG. 4, the feed roller 14 between the manual feed tray 12 and the registration roller ll in the example of FIG. 1 is omitted, and the sheet material is directly manually fed from the manual feed tray 12 between the registration roller pair 11eti. In this example, reference numeral 26 denotes a manual paper feed sensor provided closer to the pair of registration rollers 11, 11 on the clearing side in the sheet material manual feeding direction than the pair of registration rollers 11, 11.

Insert the sheet material along the manual feed tray 12 and push it until the leading edge of the sheet material passes through the manual feed sensor 26 and is sandwiched between the pair of registration rollers 11, 11. It will temporarily stop in that state, and after a few seconds, the registration rollers will pass through the manual feed sensor 26. vs. 11.11
rotates at a predetermined timing, and the sheet material is fed between the photosensitive drum and the transfer charger.

The above configuration eliminates the need for a feed roller dedicated to manual feeding, making it possible to simplify the drive device.

C. As described in detail, according to the present invention, sheet materials are selectively discharged in different directions depending on the opening/closing position of the sheet material discharge tray with respect to the main body of the apparatus, and each sheet material is selectively discharged in different directions. When a sheet material discharging direction having a curved portion with a small radius is selected for the sheet material discharging path in the discharging direction, the sheet material manual feeding port is closed by the sheet material discharging tray, so that the sheet material discharging path has a radius. Manual feeding of the sheet material is possible only when a discharge direction with a large curved part is selected, and the sheet material that is manually fed does not pass through the sheet material discharge path which has a curved part with a small radius. Since the sheet material is discharged through a sheet material discharge path having a curved portion, the occurrence of jams can be significantly reduced even when thick sheet materials such as cardboard and envelopes are manually fed.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a laser beam printer as an image forming apparatus showing one embodiment of the present invention, FIG. 2 is an enlarged view of a part thereof, and FIGS. 3 and 4 are sheet material feeders of modified examples. It is a longitudinal cross-sectional view of a sending part. 1 is a mounting body, 2 is an image carrier (photosensitive drum), 8 is a sheet material feeding cassette, 9 is an automatic feeding roller, 11 is a registration roller, 12 is a manual feeding tray, 14 is a manual feeding Rollers, 21-22 are discharge trays, and S is a sheet material. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1. Sheet material automatic feeding means for automatically feeding sheet materials;
It has a sheet material manual feeding means for manually feeding the sheet material from a manual feeding port, and a sheet material ejection tray that can be opened and closed with respect to the apparatus main body, and the sheet material ejection tray is configured to be opened and closed in accordance with the opening and closing position of the sheet material ejection tray with respect to the apparatus main body. The sheet material discharge tray is configured to selectively discharge sheet materials in different directions, and when a sheet material discharge direction in which the sheet material discharge path in each sheet material discharge direction has a curved portion of a small radius is selected. An image forming apparatus characterized in that the sheet material manual feeding port is configured to be closed by: 2. The image forming apparatus according to claim 1, wherein in the sheet material manual feeding means, a registration roller also serves as a manual feeding roller. 3. Image formation according to claim 2, wherein the sheet material manual feeding means has a sensor for detecting the presence or absence of the sheet material near the upstream side of the registration roller in the sheet material feeding direction. Device.