JPH0442243A - High-speed image forming device - Google Patents

Abstract

PURPOSE:To inexpensively realize the processing of many copies at a high speed by transferring the image of an original to an image holding means which is provided separately from an image carrier such as a photosensitive drum and which circulates and forming the image with the aid of forming a latent image on the image carrier based on that image. CONSTITUTION:The image information of the original if formed on the image carrier 13 as the latent image. Then, the latent image, which is developed and made to be a toner image, is transferred and held on the image holding means 21 which circulates with respect to the carrier 13. Next, the latent image is newly formed on the carrier 13 by developing the toner image transferred to the holding means 21. Then, the latent image is developed and transferred on a paper. Since the holding means 21 circulates with respect to the carrier 13 in such a way, the latent image can be repeatedly formed on the carrier 13 based on the toner image of the holding means 21. Thus, consumable goods are not specially required and the many copies of identical image are inexpen sively processed at a high speed without using a special photosensitive body.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high-speed image forming apparatus that can process multiple identical images at high speed.

[Conventional technology]

Conventionally, for the purpose of processing a large number of identical images at high speed, the electrophotographic printing method disclosed in JP-A-60-256156 and the latent image forming method disclosed in JP-A-63-292153 have been developed. Proposed.

In the method disclosed in the former publication, a photosensitive mask paper is first wound around a cylindrical drum, and an image is formed on the photosensitive mask paper. Then, the toner image is fixed on the mask photosensitive paper by passing a starter paper containing an organic solvent.

Thereafter, the same image is repeatedly obtained by applying charges of opposite polarity to the mask photosensitive paper and developing it each time.

In the method disclosed in the latter publication, a dielectric material (memory photoreceptor) capable of storing electrostatic latent images is used to repeatedly obtain the same image.

[Problem to be solved by the invention]

Conventionally, a large number of identical images have been processed at high speed using the methods described above, but each method increases the cost for image formation (copying cost).

That is, in the former method, the master photosensitive paper and the start paper are required as consumables, which increases the copying cost. In particular, the smaller the number of copies of the same document, the higher the cost per copy.

Also, although the latter method does not require any consumables,
The memory photoreceptor itself is extremely expensive, resulting in high copy costs.

SUMMARY OF THE INVENTION An object of the present invention is to provide a high-speed image forming apparatus that can process a large number of identical images at high speed without particularly requiring consumables or using a special photoreceptor.

[Failure to solve the problem]

A high-speed image forming apparatus according to a first invention includes an image carrier;
It includes an image holding means and an image forming means.

The image carrier has a toner image formed thereon according to the image information of the original, and the image holding means circulates with respect to the image carrier, and the 1-toner image of the image carrier is transferred. It also holds this transferred toner image.

The image forming means repeatedly forms a toner image on the image carrier based on the toner image held by the image holding means,
The image held in the image holding means is formed on a plurality of sheets of paper.

A high-speed image forming apparatus according to a second invention includes an image carrier;
It includes an image holding means and an image forming means.

The image carrier and image holding means are the same as those according to the first invention. Further, as described above, the image forming means repeatedly forms a toner image on an image carrier based on the toner image held by the image holding means, and transfers the image held by the image holding means to a plurality of sheets of paper. It has an exposure means and an optical system. The exposure means is for exposing the toner image held by the image holding means, and the optical system is for irradiating the image carrier with light from the exposure means.

A high-speed image forming apparatus according to a third aspect of the invention reads image information of the original by moving the original table on which the original is placed and exposing the original using an exposure means fixed to the main body of the apparatus. , comprising an image carrier similar to the above, an image holding means, and an image forming means.

The image forming means according to the present invention includes an exposure means fixed to the apparatus main body, and an optical system for irradiating the image carrier with light from the exposure means.

A high-speed image forming apparatus according to a fourth aspect of the present invention includes an image carrier similar to the above, an image holding means, and an image forming means.

The image forming means according to the present invention is arranged at a position such that the toner image held by the image holding means is exposed from the back side and the light with which the toner image is exposed is directly irradiated onto the image carrier. It has an exposure means.

[Effect]

In each of the above inventions, the image information of the original is formed as a latent image on the image bearing member, and this latent image is developed into a toner image and then transferred to an image holding means that circulates with respect to the image bearing member. Retained. Next, using the toner image transferred to this image holding means as a document, a new latent image is formed on the image carrier,
This latent image is developed and transferred to paper.

Since the image holding means circulates with respect to the image carrier,
A latent image can be repeatedly formed on the image carrier based on the toner image of the image holding means, and many sheets of the same image can be processed at high speed.

In this way, there is no need for consumables such as mask photosensitive paper as in the conventional apparatus, and the photoreceptor used in ordinary copying machines can be used as the image carrier, resulting in low cost.

In addition, especially in the third invention, the image of the image holding means can be exposed to the image carrier using the exposure means, optical system, etc. when reading the original, and a separate exposure means etc. are not required, so the cost can be further reduced. Become.

Furthermore, in a fourth aspect of the invention, the toner image held by the image holding means is exposed from the back side by the exposure means, and the image bearing member is directly irradiated with the light with which the toner image is exposed. Therefore, there is no need for an optical system between the image holding means and the image carrier, and there is no need to make troublesome adjustments to the optical system.
The structure becomes simpler. Therefore, the entire device becomes inexpensive.

〔Example〕

Embodiment FIG. 2 shows a copying machine as a high-speed image forming apparatus according to a first embodiment of the present invention.

A document table 2 is fixed to the upper surface of the copying machine main body 1, and a document holder 3 is attached to the upper part of the document table 2 so as to be openable and closable. Paper feed cassettes 4 and 5 containing paper are installed on the right side of the copying machine main body 1, and a paper discharge tray 6 from which copied sheets are ejected is installed on the left side.

In FIG. 1, which shows an enlarged view of the inside of the copying machine main body 1, a first exposure lamp 7 and an optical system 8 for reading image information of a document are provided in the upper part. The optical system 8 includes a first mirror 9 that moves below the document table 2 together with the first exposure lamp 7, and a pair of second mirrors that move in the same direction.
．． It is composed of third mirrors 10a and 10b, a lens 11, and a fourth mirror 12. As shown in the figure, the first mirror 9 can take the posture shown by the solid line and the posture shown by the broken line.

Further, a photosensitive drum 13 (image carrier) on which an electrostatic latent image is formed on the surface of the photosensitive drum 13 is arranged approximately at the center of the copying machine main body 1. Around the photoreceptor drum 13, there are a main charging device 14 that charges the photoreceptor drum I3 to a predetermined charge, a developing device 15 that develops an electrostatic latent image, and a first transfer device 16 that transfers a toner image onto paper. , a paper separation device 17 for separating paper from the photoreceptor drum 13, and the photoreceptor drum 1.
A cleaning device 19 having a cleaning device 19 (a plate for removing toner on the drum) and a static eliminating lamp 20 are arranged in this order.

Further, a transfer heald 21 that circulates with respect to the photosensitive drum 13 is arranged between the cleaning device 19 and the static elimination lamp 20 . The transfer bell I/21 is formed of a transparent insulating resin sheet, and the toner image formed on the photoreceptor drum 13-1 is transferred onto the surface thereof. That is, it has a function of holding an image of a document. Further, the transfer belt 21 is stretched between two pulleys 22 and 23, and a tension pulley 24 is provided between the two pulleys 22 and 23. tension boo 124
can take two positions, which are not shown by solid lines and broken lines in FIG. Therefore, the transfer bell 21 can be in contact with the photosensitive drum 13 (the state shown by the solid line) or in a non-contact state (the state shown by the broken line). Furthermore, in the area surrounded by the transfer belt 21, there is a second n-light lamp 25 that exposes the transfer belts 1 to 21 from the back side, and a second transfer device 26 that transfers the toner image on the photosensitive drum 13 onto the transfer belt 21. and are arranged. Note that a blade 18b for removing toner from the surface of the transfer belt 21 is provided in the cleaning device 19.

A paper feed conveyance path 27 is provided on the upstream side in the paper conveyance direction of the image forming section constituted by the photoreceptor drum 13 and the like, and a paper discharge conveyance path 28 is provided on the downstream side. Paper discharge path 2
A fixing device 29 that fixes the toner image on the transported paper and a paper ejection roller 30 are provided between the paper ejection 1 and the paper ejection 1 tray 6 .

The copying machine main body 1 includes a control section 31 as shown in FIG. The control unit 31 includes a CPU, RAM, and ROM.
It is equipped with a microcomputer consisting of, etc.

The control unit 31 is connected to a print key 32 of an operation panel arranged on the top surface of the copying machine main body 1, a key 33 for setting a high-speed copy mode, other keys 34, and other human power units. ing. The control unit 31 also includes a first
First mirror drive unit 3 for switching the attitude of the mirror 9
5, a tension pulley drive unit 36 for changing the position of the tension pulley 24, a drive unit 37 for the first and second exposure lamps, and a first drive unit 37 for the first and second exposure lamps. The drive section 38 of the second transfer device, the transfer belt drive section 39, and other output sections are connected.

Next, the operation will be explained according to the control flow chart shown in FIGS. 4A and 4B.

When a main switch (not shown) is turned on, the program is started, and in step S1, initial settings such as setting the number of copies to "1" and setting the fixing device 29 to a predetermined temperature are performed.

Next, step S2. In S3 and S4, it is determined whether the print key 32, the key 33 for setting the high-speed copy mode, or any other key has been pressed, respectively.

If each key is not pressed, return to step S2,
Waiting for key human commands.

If a key other than the print key 32 and high-speed copy key 33 is pressed, the process moves from step S4 to step S5. In step S5, various processes are executed depending on the input key, and when the processes are completed, the process returns to step S2.

If the key 33 for setting the high-speed copy mode is pressed, the process moves to step S6. In step S6,
It is determined whether the currently set operation mode is high speed copy mode. If the operating mode is the high-speed copying mode and the high-speed copying key 33 is pressed, the process moves to step S7 and the operating mode is returned to the normal copying mode. If the operating mode is the normal copying mode and the high-speed copying key 33 is pressed, the process moves to step S8 and the operating mode is set to the high-speed copying mode. After executing these processes, the process returns to step S2.

If the print key 32 is pressed, the program moves from step S2 to step S9.

In step S9, it is determined whether the high speed copy mode is set as the operation mode. If the normal copy mode is set, the process moves to step S10 and a normal copy subroutine is executed.

On the other hand, if the high-speed copy mode is set, the process moves to step Sll and a high-speed copy subroutine is executed. The normal copy subroutine is similar to conventional copy operations.

Next, the high-speed copying subroutine executed in step Sll will be explained with reference to FIG. 4B.

First, in step S20, initial settings for the high-speed copying subroutine are performed. In this initial setting, the first mirror 9 of the optical system 8 is set in the attitude shown by the solid line in FIG. Also, the first transfer device 16, the paper separation device 17, and the blade 18a
, 18b are all turned off. Next step S21
to move to. In step S21, the first exposure lamp 7 is turned on, the first exposure lamp 7 and the optical system 8 are moved, and the image of the document placed on the document table 2 is transferred to the photoreceptor drum I.
3. Focus on the image. Next, after development is performed in step S22, the process proceeds to step S23, where the toner image on the photosensitive drum 13 is transferred onto the transfer heald 21. At this time, the tension pulley 24 is at the position shown by the solid line, and the surface of the transfer heald 21 is in contact with the photosensitive drum 13.

Next, in step S24, the first mirror 9 of the optical system 8 is
Rotate 0° counterclockwise to take the position shown by the broken line in FIG. Further, in step S25, a portion for forming an image on paper is turned on. That is, the blade 18a of the cleaning device 19 and the static elimination lamp 20 are turned on, the tension pulley 24 is switched to the position shown by the broken line, and the surface of the transfer heald 21 is moved to the photoreceptor drums J and 1.
Make contact with 3.

In this state, the process moves to step S26.

In step S26, the second exposure lamp 25 is turned on to expose the image on the transfer bell l-2If from the back side.

This light is reflected by the first mirror 9 above the second exposure lamp 25 and is irradiated onto the photosensitive drum 13 via the optical system 8 . Therefore, the image on the transfer heald 21 is formed on the photosensitive drum 13. The latent image formed on the photoreceptor drum 13 in this way is developed in step 327 to be visualized as a toner image, and in step 32
At step B, the toner image is transferred onto the paper.

In step S29, it is determined whether or not copying of the set number of bones has been completed, and if copying has not been completed, step S29 is performed.
Returning to step S26, the processes from step S326 to step S29 are repeatedly executed. Further, when the copy processing for the set number of sheets is completed, the process moves to step S30. Step S30
Then, the blade 18b of the cleaning device 19 is turned on to remove the toner image on the transfer bell) 2]1, and the process returns to the main routine shown in FIG. 4A.

In this embodiment, in the high-speed copy mode, the image of the original is once transferred onto the transfer belt 21, and the image on the transfer belt 21 is used as the original to be copied onto a plurality of sheets of paper. Therefore, compared to the case where the copy process is performed in the normal copy mode, the waiting time required for the return operation of the optical system 8, etc. can be omitted, and the copy process can be performed at high speed.

Furthermore, consumables such as mask photosensitive paper, which are required in conventional devices, are not required, and a special photosensitive drum is not used.
It will be cheaper.

1st 2nd JiJ Rainbow Example The first example is an example in which the circumferential length of the photosensitive drum 13 is equal to the maximum image length. However, if the photosensitive drum is downsized and its circumference is shorter than the maximum image length, a configuration as shown in FIG. 5 will be obtained.

That is, in this second embodiment, since the diameter of the photosensitive drum 13 is small, the image of the document is transferred onto the transfer heald 21 by rotating it, for example, twice. Therefore, in addition to the configuration of the first embodiment, a blade 40 is provided between the transfer heald 21 and the static eliminating lamp 20, and a second static eliminating lamp 41 is provided on the upstream side of the cleaning device 19 in the rotational direction of the photosensitive drum. There is.

In this embodiment, when transferring the original image onto the transfer heald 21, the static elimination lamp 20 is turned on, and the second transfer device 16, paper separation device 17, second static elimination lamp 41, and blade lea are turned off. Leave it as the state. In this state,
In normal operation, a latent image of a portion of the document is formed on the photosensitive drum 13 by the optical system 8 or the like. This latent image is transferred onto the 'ζ transfer heald 21 by the second transfer device 26 in the same manner as in the first embodiment.

Then, the residual l on the photoreceptor drum 13...no,
Photoreceptor]・'Blade 40 provided directly above the ram 13
The residual charge is also removed by the static elimination lamp 20. Next, the remaining portion of the document is scanned to form a latent image of that portion on the photosensitive drum 13, and the image of this remaining portion is transferred onto the transfer heald 21 in the same manner as described above.

After transferring the image to the transfer belt 21-F, the blade 4
The blade 40 is released from contact with the photoreceptor drum 13.
The residual toner on the photoreceptor drum 13'' which has been dammed up is brought to the developing device 15 and collected.

Next, when forming an image on paper, the blade 40, the static elimination lamp 20, and the main charging device 14 are turned off, and the blade 18a and the second static elimination lamp 41 are turned on. Then, a part of the image of transfer bell l-211 was transferred to the second page. The exposure lamp 25 performs exposure, and the optical system 8 forms this image on the photoreceptor drum 13 . The latent image thus formed on the photosensitive drum 13 is developed by the developing device 15 and transferred onto a sheet of paper by the first transfer device 16.

After that, the residual 1-ner and residual charges are removed by the blade 18a and the second static elimination lamp 41, and the transfer belt 21 is removed.
The remaining image above is transferred onto the photosensitive drum 13. The subsequent operations are the same as those described above, and the remaining image is transferred to the paper.

In this way, it is possible to perform high-speed copy processing on a plurality of sheets of paper using the image on the transfer heald 21-hi as a document.

FIG. 6 shows an embodiment in which the present invention is applied to a copying machine of the type in which the document table 2 moves back and forth.

In FIG. 6, the same components as in each of the embodiments described above are denoted by the same reference numerals, and the explanation thereof will be omitted. In this third embodiment, the exposure lamp 42 and the optical system 43 are fixed to the frame of the main body of the apparatus. A reflecting plate 44 provided around the exposure lamp 42 allows the light from the exposure lamp 42 to change between an upper position as shown by a solid line and a lower position as shown by a broken line. Also, the mirror 4 of the optical system 43
5 can take the posture shown by the solid line and the posture shown by the broken line.

Further, the transfer bell 1-46 is formed of a white or light-colored insulating sheet so that it can reflect the light from the exposure lamp 42 and so that it can be distinguished from the original image when it is transferred. There is. Then, the transfer belt 46 and the roller 2
2 and the transfer roller 47. A wire serving as a transfer device is arranged inside the transfer roller 47. Further, the transfer roller 47 is connected to the transfer belt 46.
It is movable so that it can be in contact with the photoreceptor drum 13 or in a non-contact state.

A fur brush 48 for cleaning the transfer belt 46 is provided in the cleaning device 19 .

In this third embodiment, first, the reflector 44 of the exposure lamp 42 is
is in the state shown by the solid line, and the document table 2 is moved to expose the document. At this time, the mirror 45 of the optical system 43 is in the attitude shown by the solid line. Therefore, the image of the original is formed on the photosensitive drum 13 via the optical system 43. The latent image formed on the photoreceptor drum 13 is developed by the developing device 15 in the same manner as described above, and then transferred onto the transfer bell i.46 that comes into contact with the photoreceptor drum 13.

Next, when forming an image on paper, the transfer belt 46 is brought out of contact with the photosensitive drum 13. In addition, exposure lamp 4
The second reflecting plate 44 is rotated so that the light from the exposure lamp 42 is irradiated onto the transfer belt 46. Furthermore, the mirror 45 of the optical system 43 is placed in a posture as shown by the broken line.

In this state, the image transferred onto the transfer bell 46 is exposed by the exposure lamp 42 and formed on the photosensitive drum 13 via the optical system 43. This latent image is transferred to the developing device 15.
The image is developed and transferred onto paper using the first transfer device 16. After the transfer, the remaining toner is removed by the blade 18a, and the operation of forming the image on the transfer belt 46 onto the photosensitive drum 13 is repeated.

In such an embodiment, high-speed processing is possible with an inexpensive configuration as described above, and the lamp for exposing the document and the lamp for exposing the transfer belt can be used together, resulting in an even more inexpensive configuration.

No. 2 FIG. 7 shows a fourth embodiment.

In this embodiment, the transfer drum 50 is arranged close to the photoreceptor drum 13, and has the same diameter as the photoreceptor drum 13 and approximately the same size in the width direction. The transfer drum 50 is made of transparent insulating resin. Then, it can be in a state of contacting the photoreceptor drum 13 as shown by the solid line in the figure, or a non-contact state as shown by the broken line. Inside the transfer drum 50, a second transfer device 51 and a second exposure lamp 52 are provided. The second transfer device 51 and the second exposure lamp 52 are rotatably mounted on a shaft 53.
Both of them are arranged to face the photoreceptor drum 13. In FIG. 7, the second transfer material 51 faces the photosensitive drum 13. In FIG.

Further, a second cleaning device 54 is provided below the transfer drum 50. The second cleaning device 54 is provided with a blade 55 for removing residual toner on the surface of the transfer drum 50. Note that the first mirror 9 of the optical system 8 in this embodiment does not need to change its attitude, and a drive mechanism for this purpose is not provided.

In this fourth embodiment, the 1-toner image on the photoreceptor tram 13 is transferred onto the surface of the transfer drum 50 by the second transfer device 51 inside the transfer tram 50. At this time, the transfer drum 50 is in contact with the photosensitive drum 13, as shown by the solid line in FIG.

Next, when forming an image on paper, the second exposure lamp 52
is rotated to face the photoreceptor drum 13. Then, the transfer drum 50 is separated from the photosensitive drum 13 as shown by the broken line. In this state, the toner image on the transfer tram 50 is exposed from the back side by the second exposure lamp 52, and the photoreceptor drum 13 is directly irradiated with this light. The latent image formed on the photoreceptor drum 13 in this way is transferred to the developing device 15.
The first transfer device 16 performs high-speed copying onto a large number of sheets of paper.

In such an embodiment, when exposing the image on the transfer drum 50, a second
This is done using an exposure lamp 52.

Therefore, an optical system is not required between the second exposure lamp 52 and the photosensitive drum 13. Therefore, the second exposure lamp 5
There is no need for a light shielding plate to prevent the second light from leaking, and the adjustment of the optical system becomes easier.

[Other Examples]

(a) In the above embodiments, the position of the transfer belt or transfer drum, which is the image holding means, can be changed, but if these image holding means are positioned at appropriate intervals with respect to the photoreceptor drum, There is no particular need to change its position.

(b) In the embodiments described above, the present invention was applied to a copying machine, but it can be similarly applied to other devices such as printers.

〔Effect of the invention〕

As described above, according to the present invention, an image of a document is transferred to a circulating image holding means provided separately from an image bearing member such as a photoreceptor drum, and a latent image is formed on the image bearing member based on this image. Since the image is formed by forming an image, there is no need for consumables such as master photosensitive paper, which is required in conventional devices, and the photoreceptor used in ordinary copying machines can be used as an image carrier, and it can print a large number of sheets at high speed. processing is possible with an inexpensive configuration.

In addition, especially in the third invention, the image of the image holding means can be exposed to the image carrier using the exposure means, optical system, etc. when reading the original, and a separate exposure means etc. are not required, so the cost can be further reduced. Become.

Roughly, in the fourth aspect of the invention, the image held by the image holding means is exposed from the back side by the exposure means, and the image carrying member is directly irradiated with the light that exposed the image, so that the image holding means and the image holding means are exposed. No optical system is required between the body and the body.

[Brief explanation of drawings]

FIG. 1 is a partially schematic longitudinal sectional view of a copying machine according to an embodiment of the present invention, FIG. 2 is a schematic longitudinal sectional view of the copying machine, FIG. 3 is a control block diagram of the copying machine, and FIGS. FIG. 4B is a control flowchart thereof, and FIGS. 5, 6, and 7 are partially schematic cross-sectional views of a copying machine according to other embodiments of the present invention. 2... Document table, 7, 25, 42.52... Exposure lamp, 8.43... Optical system, 13... Photosensitive drum,
16.26.51...Transfer device, 47...Transfer roller, 21.46...Transfer heald, 50...Transfer 1-
U1. Patent applicant Mita Kogyo Co., Ltd. Agent Patent attorney Mitsuo Ono Yama

Claims (4)

[Claims] (1) An image carrier on which a toner image is formed according to the image information of a document, and a toner image that circulates with respect to the image carrier, the toner image on the image carrier is transferred, and the transferred toner image. an image holding means for holding a toner image; and a toner image is repeatedly formed on the image bearing member based on the toner image held by the image holding means, and the image held by the image holding means is printed on a plurality of sheets of paper. A high-speed image forming apparatus comprising: an image forming means for forming an image; (2) an image carrier on which a toner image is formed according to image information of a document; and an image carrier that circulates with respect to the image carrier, to which the toner image on the image carrier is transferred, and the transferred toner image. an image holding means for holding a toner image; and a toner image is repeatedly formed on the image bearing member based on the toner image held by the image holding means, and the image held by the image holding means is printed on a plurality of sheets of paper. the image forming means includes: an exposure means for exposing the toner image held by the image holding means; and an optical system for irradiating the image carrier with light from the exposure means. A high-speed image forming apparatus comprising: (3) A high-speed image forming apparatus that moves a document table on which a document is placed and exposes the document with exposure means fixed to the main body of the device to read image information of the document, the image information of the document being read. an image carrier on which a toner image is formed according to the image carrier; and an image holding means that circulates with respect to the image carrier, transfers the toner image on the image carrier, and holds the transferred toner image. , an image forming means for repeatedly forming a toner image on the image carrier based on the toner image held by the image holding means, and forming the image held by the image holding means on a plurality of sheets of paper; A high-speed image forming apparatus, wherein the image forming means includes: an exposure means fixed to the apparatus main body; and an optical system for irradiating the image carrier with light from the exposure means. (4) an image carrier on which a toner image is formed according to image information of a document; and an image carrier that circulates with respect to the image carrier, to which the toner image on the image carrier is transferred, and the transferred toner image. an image holding means for holding a toner image; and a toner image is repeatedly formed on the image bearing member based on the toner image held by the image holding means, and the image held by the image holding means is printed on a plurality of sheets of paper. and an image forming means for exposing the toner image held by the image holding means from the back side, and for exposing the toner image to light that is directly irradiated onto the image carrier. A high-speed image forming apparatus having an exposure means arranged at a position.