JP2004269138A - Double-sided feeding system, double-sided feeder, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet refeeding means capable of establishing a small-sized construction of the device and enhancing the easiness of performing the jam processing operation and the sheet feeding accuracy, a double-sided feeding system capable of enhancing the maintenance performance of a transfer means contributing to the image accuracy, and a double-sided feeder. <P>SOLUTION: The double-sided feeding system for use in an image forming apparatus having a double-sided printing function is to feed a sheet material along a feeding path formed from a sheet feed guide 2 installed rotatably relative to the apparatus body as a guide mechanism for the sheet fed by a sheet feeding means to an image formation part, a feeding path forming member 3 to form a feeding path for the sheet passing the transfer means 4, the transfer means 4 and refeeding means 5 and 6 installed on the feeding path forming member 3, and a sheet refeeding guide provided inside the guide 2 and the forming member 3 as a guide mechanism for the sheet to be refed toward a resist means 8. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electrophotographic image forming apparatus such as a copying machine and a printer, and more particularly, to a double-sided feeding apparatus provided for forming an image on both sides of a sheet material.
[0002]
[Prior art]
Conventionally, an image forming apparatus having a double-sided printing function of forming an image on one side of a sheet material, reversing the sheet material and re-feeding the sheet material to the image forming unit again, and forming an image on another one side, has been known. Are known. In these image forming apparatuses, a cover provided rotatably with respect to the main body of the image forming apparatus when a sheet feeding unit, a re-feeding unit, or a reversing unit or the like causes a jam. By opening, the inside is opened and the jam processing can be easily performed.
[0003]
The image forming apparatus disclosed in Patent Literature 1 has a sheet material re-feeding means provided inside a sheet material feeding guide rotatably provided with respect to the apparatus main body, and the sheet material re-feeding means is detachable. It is equipped with a double-sided feeding device that realizes an excellent jam handling operability by using a mechanism. However, the above-described double-sided feeding device has a mechanism in which sheet material feeding means is provided on the entire sheet material feeding guide, and space saving is not achieved. Further, since the sheet feeding means contributing to the feeding accuracy is configured to be detachable, the sheet feeding means is excellent in exchangeability, but the exchangeability of other members is not considered. The other members are, for example, a transfer unit that greatly contributes to the accuracy of an image, and it is desired that these members have excellent exchangeability.
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2001-2330
[Problems to be solved by the invention]
In order to solve the above-mentioned problems, the present invention can reduce the size of the apparatus, and can also perform jam processing operability, sheet material re-feeding means which contributes to sheet material feeding accuracy, and transfer which contributes to image accuracy. An object of the present invention is to provide a double-sided feeding system and a double-sided feeding device that improve the maintainability of the means. It is another object of the present invention to provide an image forming apparatus having the double-sided feeding device, which can be miniaturized, and which is excellent in jam operability and maintainability.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 provides a method of feeding a sheet material to an image forming unit by a sheet material feeding unit, performing skew correction of the sheet material by a registration unit, and The toner image on the image carrier formed in the above is transferred to a sheet material by a transfer means, and after fixing the toner image on one side of the sheet material by a fixing means, the sheet material is turned upside down by a reversing means, A double-sided feeding method used in an image forming apparatus for re-feeding again by the re-feeding means toward the registration means and transferring and fixing a toner image on another one side, wherein the double-sided feeding method is A sheet feeding guide rotatably provided with respect to the apparatus main body as a guide mechanism for the sheet fed to the image forming unit by the sheet feeding unit, and a feeding route of the sheet passing through the transfer unit are formed. Feeding feed Forming member, the transfer means provided on the feeding path forming member, and the re-feeding means, and the sheet feeding guide and the sheet feeding guide as a guide mechanism for the sheet fed again toward the registration means. This is a double-sided feeding system for feeding a sheet material according to a feeding path formed by a sheet material re-feeding guide provided inside the feeding path forming member.
According to a second aspect of the present invention, in the first aspect, the feeding path forming member provided with the transfer unit and the re-feeding unit is detachably formed on the sheet material feeding guide. Is a two-sided feeding method.
[0007]
According to a third aspect of the present invention, the sheet material is fed to the image forming unit by the sheet material feeding unit, the skew of the sheet material is corrected by the registration unit, and the sheet material is formed on the image carrier formed by the image forming unit. The toner image is transferred to the sheet material by the transfer means, and then the toner image is fixed on one side of the sheet material by the fixing means. Then, the sheet material is turned upside down by the reversing means, and is again returned to the registration means. A double-sided feeding device used in an image forming apparatus for re-feeding by a feeding unit and transferring and fixing a toner image on another one side, wherein the double-sided feeding device is an image forming unit by the sheet feeding unit. A sheet feeding guide rotatably provided with respect to the apparatus main body as a guide mechanism for the sheet fed to the apparatus, and a feeding path forming member for forming a feeding path of the sheet passing through the transfer means. Having the feeding The transfer means and the re-feeding means are both provided on the path forming member, and the sheet feeding guide and the sheet feeding guide as a guide mechanism for the sheet fed again by the re-feeding means toward the registration means. A two-sided feeding device having a sheet material re-feeding guide provided inside the feeding path forming member.
The invention according to claim 4 is the invention according to claim 3, wherein the feeding path forming member provided with the transfer unit and the re-feeding unit is detachably formed on the sheet material feeding guide. Is a two-sided feeding device.
[0008]
According to a fifth aspect of the present invention, there is provided an image forming unit including an image carrier, forming an electrostatic latent image on the image carrier, and developing the electrostatic latent image with toner to form an image. Then, the sheet material is fed to the image forming unit by the sheet material feeding unit, the skew of the sheet material is corrected by the registration unit, and the toner image on the image carrier formed by the image forming unit is transferred by the transfer unit. After the toner image is transferred to the sheet material and the toner image is fixed on one side of the sheet material by the fixing means, the sheet material is reversed by the reversing means and re-fed to the registration means again by the re-feeding means. An image forming apparatus for transferring and fixing a toner image on another side, the image forming apparatus including the double-sided feeding device according to claim 3 or 4.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view of an image forming apparatus main body according to the present invention. The image forming apparatus 100 includes an automatic document feeder and a document reading device at an upper portion, and a sheet feeding device at a lower portion. An image forming unit for forming an image on a sheet material, a reversing unit for reversing the sheet material for double-sided printing, and a double-sided feeding unit for feeding the sheet material to the image forming unit for double-sided printing are provided in a central portion of the main body. A transfer device is provided. The image forming unit includes an image carrier, and charging means for charging the image carrier surface around the image carrier, exposing means for exposing the charged image carrier surface to form a latent image, and a latent image on the image carrier surface. Developing means for supplying toner to the image to develop the image, transfer means for transferring the toner image on the image carrier to the sheet material, and fixing means for fixing the toner image on the sheet material are arranged.
[0010]
Next, the duplex feeding method and the duplex feeding device of the present invention will be described. The double-sided feeding device is provided inside a cover 1 that is formed to be rotatable with respect to the side surface of the image forming apparatus 100 in FIG.
FIG. 2 is an exploded perspective view showing the configuration of the double-sided feeding device. Although not shown, there is a pivot point on the far right side in the figure, and FIG. 2 shows a state in which the cover 1 is turned to be horizontal. FIG. 3 is an enlarged view of a longitudinal section of FIG. The double-sided feeding device of the present invention includes a cover 1 rotatably formed with respect to the main assembly of the apparatus, and a sheet feeding unit (not shown) provided at a lower portion of the image forming apparatus 100 to the image forming unit by a sheet material feeding unit. A sheet feeding guide 2 serving as a guide mechanism for the fed sheet and a feeding path forming member 3 for forming a feeding path for the sheet passing through the transfer means 4. The sheet material feeding guide 2 holds a registration unit 8 that corrects the skew of the sheet material and feeds the sheet material toward the transfer unit 4. The feeding path forming member 3 holds the transfer means 4 and the re-feeding means 5 and 6, and is fixed to the cover 1 by fastening pins 7. As described above, by providing the registration unit 8 and the transfer unit 4 on members such as the sheet material feeding guide 2 and the feeding path forming member 3, the size of the apparatus can be reduced.
Further, the space formed between the cover 1 and the sheet material feeding guide 2 and the feeding path forming member 3 is formed by a re-feeding means 5 as each member serves as a sheet material re-feeding guide. , 6 form a re-feeding path for the sheet material fed again to the registration means 8.
[0011]
The feeding method of the sheet material by this double-sided feeding device is as follows. The sheet material whose skew has been corrected by the registration means 8 is fed to the upper part of the transfer means 4 according to the sheet material feeding guide 2, and the toner image on an image carrier (not shown) arranged opposite to the transfer means 4 is removed. It is transferred when passing through a nip formed by the image carrier and the transfer means 4. The sheet material after the transfer of the toner image is conveyed to a fixing unit (not shown), and the toner image is fixed on the sheet material. As a result, the image formation on one side is completed. Thereafter, in order to form an image on another one side, the sheet material is conveyed to a reversing unit (not shown) and turned over. The sheet material after the reversion is returned to the double-sided feeding device again, is fed toward the registration unit 8 by the re-feeding units 5 and 6, and includes the cover 1, the sheet feeding guide 2, and the feeding path forming member. 3 through the re-feeding path formed between them.
[0012]
In the double-sided feeding device shown in FIG. 2, the feeding path forming member 3 including the transfer means 4 and the re-feeding means 5 and 6 can be freely attached to and detached from the sheet material feeding guide 2 by inserting and removing fastening pins 7. You can do it. The fastening pins 7 may use rivets, screws, or the like. Accordingly, it is possible to easily process a jam that has occurred on the sheet material re-feeding path. In addition, not only can the respective members of the re-feeding means 5 and 6 be exchanged, but also the transfer means 4 provided on the feeding path forming member 3 together with the re-feeding means 5 and 6 can be similarly replaced. When replacement is required, for example, at the end of the service life, the replacement can be easily performed, and the configuration is excellent in maintainability.
[0013]
【The invention's effect】
As described above, according to the present invention, the transfer unit and the re-feeding unit are provided on the same member, and are formed detachably with respect to the sheet feeding guide. A double-sided feeding method and a double-sided feeding device with improved maintainability can be provided. Further, with the configuration of the double-sided feeding device, it is possible to provide an image forming apparatus that can be reduced in size, and is excellent in jam operability and maintainability.
[Brief description of the drawings]
FIG. 1 is a perspective view of an image forming apparatus main body according to the present invention.
FIG. 2 is an exploded perspective view showing a configuration of a two-sided feeding device.
FIG. 3 is an enlarged view showing a longitudinal section of FIG. 2;
[Explanation of symbols]
REFERENCE SIGNS LIST 1 cover 2 sheet material feeding guide 3 feeding path forming member 4 transfer means 5, 6 re-feeding means 7 fastening pin 8 registration means 100 image forming apparatus

Claims (5)

The sheet material is fed to the image forming unit by the sheet material feeding unit, skew correction of the sheet material is performed by the registration unit, and the toner image on the image carrier formed by the image forming unit is transferred to the sheet material by the transfer unit. After the toner image is fixed on one side of the sheet material by the fixing means, the sheet material is turned upside down by the reversing means, and is again fed again by the re-feeding means toward the registration means, A two-sided feeding method used in an image forming apparatus for transferring and fixing a toner image on another one side,
The two-sided sheet feeding method includes a sheet material feeding guide rotatably provided with respect to the apparatus main body as a guide mechanism for a sheet material fed to an image forming unit by the sheet feeding means, and passing through a transfer means. A sheet re-feeding member for forming a sheet-supplying path for the sheet material, the transfer means provided on the sheet-feeding path forming member, the re-feeding means, and a sheet re-fed toward the registration means A sheet material is fed according to a sheet feeding path formed by the sheet material feeding guide and a sheet material re-feeding guide provided inside the sheet feeding path forming member as a sheet guiding mechanism. Double-sided feeding method. 2. The double-sided feeding according to claim 1, wherein the feeding path forming member provided with the transfer unit and the re-feeding unit is formed detachably with respect to the sheet material feeding guide. 3. method. The sheet material is fed to the image forming unit by the sheet material feeding unit, skew correction of the sheet material is performed by the registration unit, and the toner image on the image carrier formed by the image forming unit is transferred to the sheet material by the transfer unit. After the toner image is fixed on one side of the sheet material by the fixing means, the sheet material is turned upside down by the reversing means, and is again fed again by the re-feeding means toward the registration means, A two-sided feeding device used in an image forming apparatus that transfers and fixes a toner image on another side,
The double-sided feeding device passes a sheet material feeding guide rotatably provided with respect to the apparatus main body as a guide mechanism for the sheet material fed to the image forming unit by the sheet feeding device, and passes through a transfer device. A sheet feed path forming member for forming a sheet material feeding path; and the transfer means and the re-feeding means both provided on the sheet feeding path forming member. And a sheet material re-feeding guide provided inside the sheet feeding path forming member as a sheet material guide mechanism for re-feeding the sheet material toward the means. Feeder. The double-sided feeding according to claim 3, wherein the feeding path forming member provided with the transfer unit and the re-feeding unit is formed detachably with respect to the sheet material feeding guide. apparatus. An image forming unit that forms an electrostatic latent image on the image bearing member, and forms an image by developing the electrostatic latent image with toner; The sheet material is fed to the image forming unit, the skew of the sheet material is corrected by the registration unit, the toner image on the image carrier formed by the image forming unit is transferred to the sheet material by the transfer unit, and then the fixing unit After fixing the toner image on one side of the sheet material, the sheet material is reversed by the reversing means, re-fed again to the registration means by the re-feeding means, and the toner image is transferred to another one side. In the image forming apparatus to be fixed,
An image forming apparatus, comprising: the double-sided feeding device according to claim 3.

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