JPH0869136A - Image forming device with document feeder - Google Patents

Abstract

PURPOSE: To simplify and lighten the constitution of a document feeder and to reduce restriction on design as well by reversing the reverse carrying path of the second surface of a both-side document in a document feeder through the use of the carrying path of an image forming device main body, that is, the paths of both surfaces used at the time of copying on a recording paper and a rear surface ejecting path. CONSTITUTION: At the time of copying the rear side, first, the document in a document reading part 16 is returned by the reverse rotation of a document feeding roller 18 and fed to a copying device main body side by a document switching back flapper 17. After the document passes through a rear surface ejecting unit roller 13, the document is guided to a document back roller 15 by the rotation of a reverse roller 19 and a flapper 25 and then, returned to the rear surface ejecting unit roller 13 by the work of the reverse rotation of the roller 15 and the flapper 25, to be rushed into the document reading part 16 with the document switching back flapper 17 again by the reverse rotations of the unit roller 13 and a roller 20 with the document switching back flapper 17. At this time, the document is turned upside down. After that, the rear surface is copied in the same procedure as that of the front surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus provided with a document feeding device, and more particularly, to an automatic document feeding device which is provided in an image forming device such as a copying machine or a facsimile to automatically feed a document. The present invention relates to a double-sided document front-back inverting means.

[0002]

2. Description of the Related Art In the case of double-sided feeding of a conventional automatic document feeder, as shown in FIG.
Is formed in a branched manner, and the one-side read document that is being discharged is reversed and returned to the reading unit 16. On the other hand, for single-sided originals,
In the configuration shown in FIG. 3, the document separated by the separation / feed roller 12 is sent to the reading unit 16 by the roller 18 through the path I. Thereafter, the rollers 18 are rotated in the reverse direction to be guided by the flapper 21, passed through the path II by the rotation of the drum 22, guided by the flapper 23, passed through the discharge path III, and discharged onto the tray.

[0003]

However, in the above-mentioned conventional example, the conveying path of the automatic document feeder becomes complicated and the weight also increases.

As a result, the hinge attached to the main body side, which supports the automatic document feeder, needs to have high rigidity, which leads to a high cost.

A large drum 2 as shown in FIG. 3 is used for reversing.
2 was required, which resulted in high cost and design restrictions.

[0006]

Means (and Action) for Solving the Problems
The reverse conveyance path for the second side of the double-sided original of the document feeder is used as the conveyance path of the main body of the image forming apparatus. By reversing and reversing, the document feeding device has no reversing conveyance path.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an overall view of an image forming apparatus that best represents the present invention. A is a document feeder and B is an image forming apparatus main body.

First, the document 11 on the tray 27 is separated and fed by the document separating / feeding roller 12, passes through the path I and the document feeding roller 18 (FIG. 1B), and is set in the document reading section 16. Then, the original data is read into the CCD unit 7 through the optical system. afterwards,
The data input to the CCD unit 7 is output from the polygon scanner unit 6 by laser light. This laser light strikes the photosensitive drum 1.

Next, the recording paper 9 is conveyed to the registration roller 10 by the paper feed roller 8, and the electrostatic image formed by the laser beam is sent at the timing of developing and transferring to form an image on the recording paper. Then, after the toner is stably fixed on the recording paper by the fixing device 4, the back surface paper discharge unit 1
3, the reversing roller 19 and the flapper 25 reverse the recording sheet, and the recording sheet is passed through the roller 15 and temporarily stored in the intermediate tray 14.

Next, copying on the back side will be described.

First, the original in the original reading section 16 is returned by the reverse rotation of the original feeding roller 18, and the original is sent to the copying apparatus main body side by the original switchback flapper 17 (FIG. 1 (c)). After passing through the rear surface discharge unit roller 13, the reverse roller 19 and the flapper 25 guide the document to the original back roller 15, and then the reverse rotation of the roller 15 and the flapper 25 return the sheet to the rear surface discharge unit 13. 13 and roller 20
The reverse rotation causes the document switchback flapper 17 to enter the document reading unit 16 again. At this time, the front and back of the document are reversed. Then the intermediate tray 1
The sheet is re-fed by the sheet feeding roller 8 from 4, and is copied on the back side in the same procedure as the front side.

Finally, the original document in the original reading section 16 is read by the original document switchback flapper 17 and the original feeding roller 1.
Due to the reverse rotation of 8, the original is returned to the position where it started and the double-sided copying is completed. After that, the document is discharged to the tray 28.

As a result, the original reversing roller unit 24 as shown in FIG. 3, which is conventionally required, can be eliminated.

In the embodiment shown in FIG. 1, the flapper 17 is controlled by a solenoid (rotary solenoid or the like) and is normally in the position shown in FIG. 1 (b). When the processing of a double-sided original is instructed and the roller 18 starts to rotate in the reverse direction after reading, the flapper 17 rotates counterclockwise to the state of FIG. When the front and back of the document are reversed and returned and the roller 18 rotates in the normal direction, the trailing edge of the document fed by the normal rotation passes through the flapper, and the solenoid rotates to the right to prepare for the next document.

The entire document feeder can be opened and closed by supporting the left and right rear hinges, and a book document can be set on the reading section. An entrance (communication part) to the main body of the image forming apparatus is formed between the roller 18 and the exit of the path I on the lower surface of the document feeder.

Further, in the figure, the rollers 12 and 18 are controlled by the CPU (control circuit) of the document feeder, and this CPU is connected to the CPU (control circuit) of the main body of the copying machine. The rollers 13, 15, 19 and 20 are C of the main body of the copying machine.
Controlled by PU. The flappers 17, 25, and 26 are also the same.

It should be noted that the flapper 26 is in a posture of guiding the sheet material straight from the roller 14 to the discharge tray 5 at the time of one-sided copying, and is initially in a posture of guiding the sheet material from the roller 14 to the roller 13 at the time of double-sided copying. And then returns to the posture in which the roller 14 guides the tray 5. Further, when the document is fed, the posture is such that the roller 20 feeds the roller 13 and the roller 13 feeds the roller 20.

Regarding the flapper 25, the posture of feeding the sheet material (or the original document) from the roller 13 to the roller 19 is switched to the posture of sending the sheet material from the roller 19 to the roller 15, and then the posture of feeding from the roller 15 to the roller 13 is switched.

(Other Embodiments) FIG. 2 is a diagram specifically showing another embodiment.

By making the conveyance path 30 (flapper 17, roller 20) attached to the main body side of the reversing path optional, it is intended to provide an inexpensive machine to those who use only the main body which does not use reversal. The other structure is similar to that of the first embodiment and will not be described. Therefore, the transport path unit 30 is attachable to and detachable from the main body, and can be attached or detached as needed. After removing the unit 30, a guide plate is assembled above the flapper 31.

In FIG. 2, a mylar 29 is attached to the exit of the path I, and the original is guided to the roller 18 when the flapper 17 is in the state shown in FIG. 1 (b). On the contrary, when the flapper 17 is switched to the state shown in FIG. 1C, the mylar 29 is pushed away by the flapper 17. Therefore, the document is guided by the mylar 29 when the option 30 is not attached.

Although the embodiment of the present invention is as described above, the present invention is not limited to this.

For example, the discharge tray 28 is omitted and FIG.
Similarly to the above, the configuration may be such that the document tray 27 is switched back and returned.

Further, instead of the roller 18, a transport belt which rotates in the forward and reverse directions may be arranged, the original may be set on the platen glass of the apparatus main body, and the optical system may be moved to read the original.

Further, instead of the reversing path for reversing the front and back of the sheet material to the intermediate tray and storing it, a reversing path for reversing the front and back of the sheet material and discharging may be used. This will be described with reference to FIG.
Roller 20 → Roller 13 → Roller 13 reverse rotation → Exit roller (at the entrance of tray 5) → Exit roller reverse rotation → Roller 2
The original is sent with 0. During that time, a plurality of flappers 26 are switched.

[0026]

As described above, according to the present invention, since the document is turned upside down by using the conveying path on the main body, the structure of the document feeding device is simplified, and the weight is reduced. This has the effect of reducing design restrictions.

[Brief description of drawings]

FIG. 1 is a diagram showing the present embodiment, FIG. 1 (a) is an overall front sectional view, and FIGS. 1 (b) and 1 (c) are enlarged views showing the operation of a flapper 17.

2A and 2B are views showing another embodiment, FIG. 2A is an overall front sectional view, and FIG. 2B is an enlarged view.

FIG. 3 is a front sectional view of a conventional example.

[Explanation of symbols]

 12 Separation / Feeding Rollers 13, 15, 19, 20 Forward / Reverse Roller 17, 25, 26 Flapper 14 Intermediate Tray 16 Reading Section 18 Document Feeding Roller

Claims (5)

[Claims] 1. An image forming apparatus including an apparatus for automatically feeding a document, the image forming apparatus including a double-sided document reversing unit on a main body side of the image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the double-sided document reversing means reverses the document by using a double-sided reversing mechanism of the sheet material on the main body side and moves the document to the document reading section. 3. A conveyance path unit for use in the image forming apparatus according to claim 1, comprising a flapper for guiding the document of the document feeding apparatus into the conveyance path of the image forming apparatus main body. 4. The apparatus according to claim 1, wherein a part of the conveying means for guiding the original of the original feeding device into the conveying path of the image forming apparatus main body is unitized and detachable. Image forming apparatus. 5. An original feeding device used in the image forming apparatus main body according to claim 1 or 2, which is provided with an original inlet for the original to the apparatus main body.