JPS5995566A - Fixing and retention device of copying machine - Google Patents

Abstract

PURPOSE:To reduce the number of parts and to reduce cost by using a laser beam for fixing an unfixed toner image, and guiding the reflected light of the laser beam to a photosensitive body and forming an original image on the surface of the photosensitive body again by exposure. CONSTITUTION:A latent image formed on the photosensitive body 15 by exposing an original mounted on a platen 20 is developed and its toner image is transferred to a form 30 by a transfer corotron 29. Then, the form having the unfixed toner image is irradiated with the scanning laser beam from a laser light source 18 through a polygon mirror 17 while moved along a form conveyance path, fixing the toner image. The reflected light of the laser beam used for the fixation of the toner image on the form, illuminates the surface of the photosensitive body 15 through a mirror 26, etc., to form an image on the photosensitive body 15 again by exposure. The photosensitive body 15 enters developing operation on the basis of said image and this image is transferred to the form 30 by the transfer corotron 29; and this operation is repeated.

Description

[Detailed description of the invention] The present invention relates to a fixing and retention device for a copying machine.

As shown in FIG. 1, a copying machine equipped with a conventional retention device emits light from a light source 2 to a document placed on a platen 1, and guides the reflected light from a mirror 3 to an irradiation mirror 5 via a lens 4. , the surface of the photoreceptor 6 is irradiated from the irradiation mirror 5 to form a latent image, and the latent image is developed with a dust imager (not shown), transferred onto a commercial IeB with the transfer corotron 1, and then fixed. Before the paper is fixed by the fixing device 9 and discharged from the paper exit to the outside of the machine, a light source 10 is arranged in the paper conveyance path between the transfer point of the photoreceptor 6 and the fixing device. The unfixed toner image formed on the photoconductor 60 is emitted, and the reflected light is passed through the mirror 11, lens 12, and filter 13, and is exposed and imaged again on the surface of the photoreceptor 60 by the optical path switching mirror 14. All of the apparatuses were constructed to make the required number of copies based on the toner image on the sheet of paper onto which the developed image was transferred onto the surface of the photoreceptor 6.

However, in a copying machine with such a configuration, the fixing device that fixes the unfixed toner image formed on the paper and the retention device for the folded image are provided separately, so the number of parts is also increased. It has the disadvantage that it requires a large number of units, which increases the production cost accordingly, and that it requires extra space for installation.

The present invention has been made to eliminate the above-mentioned drawbacks of conventional copying machines, and uses a laser beam to fix an unfixed toner image formed on paper.
It is an object of the present invention to provide a fixing/retention device for a copying machine, which guides reflected light of a laser beam used for fixing to a photoreceptor to re-expose and form a printed image on the surface of the photoreceptor.

The present invention will be described in detail below based on embodiments shown in the drawings.

FIG. 2 is a schematic diagram showing an embodiment of the fixing and retention device of the present invention.

A rotary polyhedral mirror 17 equipped with a motor 16 is disposed on a paper transport path from the transfer point of the photoreceptor 15 to a paper discharge port (not shown). A laser light source 18 is placed at a suitable location near the paper transport path with respect to the polyhedral mirror 17, and the laser beam irradiated from the laser light source 1B is directed to the paper transport path by the polyhedral mirror 17, and the polyhedral mirror 17 is rotated. Along with the prescribed devotion of the paper transport path.

This enables high-speed orthogonal scanning to the transport direction, and a correction lens 19 for correcting the optical path of the laser beam is disposed in the middle of the optical path.

On the other hand, a light source 21 emits light from a document placed on a platen 20, and a mirror 22, a lens 23, and an irradiation lens 24 are provided to guide the reflected light to the surface of the photoreceptor 13. An anatomical lens 25 is rotatably disposed near the middle between the irradiation lens 24 and the sensor body 15, and is located midway between the irradiation lens 25 and the point where the laser beam from the polyhedral mirror 17 in the paper conveyance path falls. includes a mirror 26, a correction lens 2T for correcting the optical path of the beam, and a filter 28 for adapting the sensitivity to the wavelength of the photoreceptor 15.
Place.

The operation of the fixing/retention device of the present invention constructed as described above will be described below.

The light source 21 emits light to the Quryo manuscript currently placed on the platen 1T, and the reflected light is guided to the mirror 22.
2 to the irradiation mirror 24 via the lens 23,
A latent image is formed on the surface of the photoreceptor 13 by irradiating the surface of the photoreceptor 150 from the single-emission mirror 24 . The latent image is formed by a clay spreader (not shown), and its toner image is transferred onto the paper 30 by a transfer corotron 29.

After the toner image has been transferred, the paper heads to the paper exit outlet along the paper conveyance path where the toner image is not fixed. When the tip of the dissecting mirror 25 is detected, the laser beam 18 is driven by the signal, and at the same time as the laser beam is emitted, the polyhedral mirror 17 starts rotating, and the dissecting mirror 25 also rotates, so that the laser beam 18 is moved from the irradiation mirror 24 to the photoreceptor 15. At the same time, the reflected light from the irradiation point of the laser beam irradiated from the polyhedral mirror 17 in the paper conveyance path is allowed to irradiate the surface of the N&former pot body 150 through the same optical path.

The laser beam emitted from the laser light source 18 is reflected by a polygonal mirror 17, and as the polygonal mirror 17 rotates, the laser beam is scanned in the paper wrinkle feeding direction and in the field angle direction. Since the rotational speed of the polyhedral mirror 170 is extremely high, the scanning operation with the polyhedral mirror 170 is repeated as the paper moves slightly. The fixation is performed evenly.

On the other hand, the reflected light of the laser beam used for this fixing goes from the irradiation point of the beam on the paper to the mirror 26, and is guided from the mirror 26 to the irradiation lens 25 via the correction lens 27 and filter 28, and from there. The surface of the photoreceptor 15 is irradiated, and the toner image on the paper is re-exposure imaged on the photoreceptor 15.

The photoreceptor 15 reactivates the parent body based on this image, and this toner image is transferred onto the paper 30 by the transfer corotron 29 and fixed by the laser beam. It is repeated according to the number of sheets.

The present invention is constructed and operates as described above, in which a laser beam is used to fix an unfixed toner image formed on paper, and its reflected light is also used in the retention optical system. However, the operation is a special IS that requires no retention other than rotating the irradiation mirror 22! Since no structure is required, the benefits of high-speed copying due to retention can be enjoyed without increasing the number of parts or costs.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a copying machine equipped with a conventional retention device, and FIG. 2 is a schematic diagram of a fixing/retention device according to the present invention. 13...Fist/photoreceptor, 16...Laser light source, 22
...Irradiation mirror, 23-...Mirror, 24...
・Correction lens. Patent applicant Fuji Xerox Co., Ltd.

Claims (1)

[Claims] A laser light source is placed at an appropriate location near the paper conveyance path behind the transfer point of the photoconductor, and the laser beam emitted from the laser light source can be scanned orthogonally to the conveyance direction at high speed at a predetermined position for paper conveyance. The laser beam is used to fix the unfixed toner image formed on the paper, and the reflection of the laser beam from the paper at the time of fixing is applied to the photoreceptor using an arbitrary number of mirrors and correction lenses. A fixing and retention device for a copying machine, characterized in that the toner image being fixed on the photoreceptor can be re-exposed and imaged.