JPH02257178A - Recording device - Google Patents

Abstract

PURPOSE:To prevent the contamination of the operation part of a fixing means from occurring by shielding the operation part of the fixing means with the aid of a shielding means excepting a time for fixing a master image on an image carrier with the aid of the fixing means. CONSTITUTION:The operation part 90 of the fixing means 9 is shielded with the aid of the shielding means 60 excepting the time for fixing the master image on the image carrier 2 with the aid of the fixing means 9. When the master image is fixed on the image carrier 2 with the aid of the fixing means 9, the shielding means 60 is made in an open state by tightly aligning the window 61 thereof before the front surface 90 of the fixing means 9. Otherwise, the means 60 is taken up to either of rollers 62 and 63 to be in a closed state that it covers the front surface 90. Thus, the contamination of the operation part 90 caused by the adhesion of 1st and 2nd developer is prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording device used as a copying machine or a printer.

[Prior Art] An electronic copying machine or a plate-making/printing machine is known as a device for copying a document.

Generally, when making fewer than 1,000 copies of the same manuscript, an electronic copying machine is used because of the simplicity of the setup, and beyond that.
When it is necessary to make two copies in one summer, a plate making/printing machine is often used due to cost considerations.

However, with the passage of time, there is a growing tendency to seek cheaper duplication costs, simpler operations, and faster processing.

To address these problems, electronic copying machines have traditionally been able to copy at a speed that is closer to that of printing.
Moreover, devices that do not require skilled work or setup, such as plate-making and printing machines, are being put into practical use. However, in order to further increase the copying speed, the electric power required for exposing the original, fixing the developer, charging, etc. becomes extremely large, and there is a serious problem that a normal commercial power source (100V 15A) cannot be used.

Therefore, the present applicant proposed in Japanese Patent Laid-Open No. 63-29273 a completely new system that can reproduce a large number of copies at a high speed similar to a printing machine with the same simple operation as an electronic copying machine, and with low power consumption. proposed a recording device.

This new recording device forms an electrostatic latent image on an image carrier by a writing means, develops this electrostatic latent image with a first magnetic developer, and then fixes this developer image on the image carrier. A master image is obtained, and then this master image is magnetized and a second magnetic developer is adhered thereon to obtain a transferred image, which is then transferred to a transfer material.

In such a system, even after the transferred image on the master image is transferred to the transferred material, the master image remains on the image carrier with its magnetic force retained, so that the second and subsequent images When performing the same duplication, a second magnetic developer is attached to this mask image using the magnetic force of the master image again to form a transferred image, and this developer image is transferred to the transferred material. Just let it happen. By repeating this process, copies can be made from the same original any number of times. That is, in this printing mode, after forming the master image,
The aforementioned charging process, the process of forming an electrostatic latent image, the process of developing an electrostatic latent image, and the process of fixing a developer image on an image carrier are not required at all. Therefore, when a large number of copies are made using this printing mode, power consumption can be reduced and the copying speed is much faster than that of conventional electronic copying machines.

[Problems to be Solved by the Invention] However, in the proposed device, the first and second developers may adhere to the working part of the means for fixing the master image, causing the working part to be damaged. A problem arose in that the image was stained, making it impossible to perform uniform fixing work.

The present invention has been made in view of these problems, and an object of the present invention is to provide a recording device of this type that can prevent contamination of the working part of the fixing means and perform stable printing. do.

[Means for Solving the Problems] In order to achieve the above object, the recording device of the present invention uses a moving image carrier and a first developer containing a magnetic material capable of permanent magnetization. a writing device for forming an image on the image carrier; a fixing device for fixing the developer image formed by the writing device as a mask image; and a fixing device for fixing the developer image formed by the writing device as a mask image; a magnetic latent image forming means for forming a magnetic latent image on a material; a developing means for developing the magnetic latent image with a magnetic second developer; and a transfer means for transferring the second developer image onto a transfer material. , is provided. In the present invention, the working part of the fixing means is covered with a shielding means that can be opened and closed, and the working part of the fixing means is covered by the shielding means except when the mask image is fixed on the image carrier by the fixing means. I tried to cover it.

[Function] According to the above item 11), in the present invention, the shielding means that covers the working part of the fixing means prevents the working part from being contaminated by the adhesion of the first and second developers. do.

"Example code" Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 2 shows the configuration of the recording apparatus of the present invention. In the figure, reference numeral 1 denotes the main body of the apparatus, and a drum-shaped image carrier 2 is arranged approximately in the center of the main body 1 of the apparatus, and around the image carrier 2, as shown in FIG. Along the rotation direction (direction of arrow a), the charging means 3° and the exposing section 4 of the electrostatic latent image forming means 4
A and ml developing means 5 are provided, and these constitute a writing means.

Further, the second developing means 6. Pre-transfer charging means 7
．． Transfer means8. Master image fixing means9. Static elimination means 10.
and a master image magnetizing means, that is, a magnetic latent image forming means 11 are arranged in this order.

Further, inside the apparatus main body 1, paper P as a transfer material fed from a paper feed cassette 12 mounted on the right side of the apparatus main body 1 via a paper feed means 13 is stored as the image j A paper conveyance path 16 is formed which conveys the paper through the image transfer section 14 between the transfer means 8 and the paper discharge tray 15 mounted on the left side of the main body 1 of the apparatus.

Further, a pair of aligning rollers 17 is arranged on the upstream side of the paper transport path 16, and a fixing means 18 and a pair of paper ejection rollers 19 are arranged on the downstream side. Furthermore, the fixing means 18
A cooling fan unit 20 is provided above.

Further, at the upper part of the apparatus main body 1, a document reading means 22 is provided which reads a document placed on a document table 21 and outputs an image signal. The document reading means 22 includes an exposure lamp 24 mounted on a carriage 23 that reciprocates in the horizontal direction (in the direction of the arrow) along the surface of the document, and which irradiates light onto the document.
．． Optical transmission body 25 that transmits reflected light from the original document. and a well-known scanner unit equipped with a photoelectric conversion element (CCD) 26 that converts an optical signal transmitted via an optical transmission body 25 into an electrical signal. Incidentally, reference numeral 27 denotes an openable and closable document presser that presses the document tray.

Further, the image carrier 2 has a structure in which a photoreceptor belt 31 having a photosensitive layer 31a of zinc oxide sensitized to a long wavelength with a dye such as rose bengal is wound around the outer periphery of a non-magnetic drum 30. A drive mechanism (not shown) rotates at least a first speed v1 and a second speed V2 several to several tens of times faster than this. Further, the photoreceptor belt 31 has both ends thereof wound around a feeding core 32 and a winding core 33 disposed inside the non-magnetic drum 30, and a middle portion thereof is wound around the outer periphery of the non-magnetic drum 30. almost 1
It is wrapped around it. A photoreceptor belt 31 is wound around the feeding core 32 in the form of a roll, and each time a printing mode to be described later is performed, a new photosensitive belt 31 of a predetermined size can be fed onto the non-magnetic drum 30. The used portion is wound up on a winding core 33. A slit 34 is formed in the non-magnetic drum 30 for feeding out a new portion of the photoreceptor belt 31 or introducing a used portion. Further, if necessary, the image of the used portion that has already been used can be rewound and used.

The charging means 3 is a corotron type corona charger, and charges the image carrier 2, that is, the photosensitive layer 31a, at -300
It is designed to uniformly charge the battery to -500 volts.

The electrostatic latent image forming means 4 is composed of a known laser exposure device, and exposes the photosensitive layer 31a with a laser beam β based on the image information read by the document reading means 22 to form the photosensitive layer 3.
An electrostatic latent image corresponding to image information is formed on 1a.

The first developing means 5 is composed of a developing device employing a magnetic-component developing system, and uses a first magnetic developer TI, which is a carrierless donor. The magnetic material in the first magnetic developer Tl has a larger residual magnetization and a larger coercive force than conventionally used magnetic materials. These materials include 7-F e203 and Fe304.

Co-7-Fe203. CrO2,Fe (metal powder)
or barium ferrite are suitable. Then, these fine powders are mixed with the resin in an amount of 20 to 80% by weight to obtain particles having an average particle size of 1 to 30 μm, which is used as developer TI. Note that this first developing means 5 uses magnetic developer T1.
is carried to the image carrier 2 side as the magnetic sleeve 40 rotates.

The second developing means 6 is composed of a developing device that employs a magnetic component developing method, and is made of Fe, which has high resistance and low residual magnetization.
A second magnetic developer T2 made of magnetic powder such as 2O4 is used, and this magnetic developer, ie, toner T2, is carried to the image carrier 2 side as the magnetic sleeve 41 rotates.

The magnetic force of the magnetic sleeve 41 of the second developing means 6 is set in consideration of the magnetic force of the developer image developed by the first developing means 5. That is, if the magnetic force of the magnetic sleeve 41 of the second developing means 6 is too large, the developing efficiency will be low and a clear image cannot be obtained, and if it is too small, the second developer T2 will not be conveyed effectively. Furthermore,
If the magnetic sleeve 41 of the second developing means 6 forms an external magnetic field that exceeds the holding power of the developer image developed by the first developing means 5, the magnetic latent image will disappear. It is necessary to select the magnetic force of the 7-gnet sleeve 41 of the second developing means 6 in consideration of the following two factors.

The pre-transfer charging means 7 consists of a corona charger, and the photosensitive layer 3
Negative polarity is used so that the charge remaining on 1a can be erased by photostatic discharge.

The transfer means 8 transfers a layer onto the surface of the belt body made of a conductive material.
It consists of an endless transfer belt 43 laminated with dielectric films such as polyester having a thickness of about 20 to 40 μm, and a bias voltage of about 1000 volts with the opposite polarity to that of the corona charger as the pre-transfer charging means 7 is applied. be done. Also,
The transfer belt 43 forms a part of the paper conveyance path 16, and its conveyance end side extends to the entrance of the fixing means 18. Then, the transferred image is transferred to the paper P side, and the paper P is peeled off from the image carrier 2 and guided to the fixing means 18. Note that instead of applying the bias voltage to the transfer belt 43, transfer and peeling may be performed by applying an electric charge to the paper P by corona discharge.

The master image fixing means 9 fixes the developer image visualized by the first developing means 5 on the photoreceptor belt 31 by a fixing flash using a xenon lamp or the like to form a magnetic master image 52. be.

As shown in FIG. 1, the front surface 90 of the master image fixing means 9
That is, the working part is surrounded by a heat-resistant and non-light-transparent shielding means 60 that can be opened and closed. The shielding means 60 has a window 61 formed in the middle part, and rollers 62.6 at both ends.
3, and can be driven in the longitudinal direction by a motor (not shown). The shielding means 60 is connected to the fixing means 9
When fixing the master image on the image carrier 2, the window 61 is aligned with the front surface 90 of the fixing means 9 and is in the open state, and at other times, the window 61 is wound around one of the rollers 62 and 63 and the window 61 is opened. It is designed to be in a shielding state that covers the front surface 90.

The static eliminating means 10 includes a static eliminating lamp that removes residual charges by irradiating the image carrier 2 with static eliminating light.

The master image magnetizing means, that is, the magnetic latent image forming means 11 has a fourth
As shown in the figure, it is composed of a magnetic head 50.

Next, the operation of the recording apparatus having the configuration as described in 1- will be explained. This apparatus is capable of duplicating the original A in any mode, either a print mode suitable for duplicating a large number of sheets from the same original D]2 or a copy mode suitable for duplicating a small number of sheets. First, the print mode will be explained.

As the document reading means 22 starts reading the document, the image carrier 2 consisting of the non-magnetic drum 30 and the photoreceptor belt 31 rotates in the direction of the arrow a at a first speed v1, and as shown in FIG. As shown in a), the photosensitive layer 31a of the photosensitive belt 31 is uniformly negatively charged by the charging means 3. 1. The image information read by the original reading means 22 is photoelectrically converted into a signal by a known means, and the electrostatic latent image forming means 4 emits a laser beam ρ corresponding to the image information onto the photosensitive layer 31a. By performing the irradiation, electrostatic latent images are formed one after another as shown in FIG. 4(b).

The electrostatic latent image thus obtained is developed when passing through the first developing means 5. In the developer image forming step by the first developing means 5, as shown in FIG. 4(C),
A developer image 51 corresponding to an image is obtained by electrostatically adhering the first magnetic developer Tl induced with a positive charge to a negative charge of the photosensitive layer 31a.

This developer image 51 is transferred to the second developing means 6 by rotating the image carrier 2 at the first speed v1. Pre-transfer charging means 7
．． It passes through the image transfer section 14 without any relationship therewith.

When the developer image 51 faces the master image fixing means 9, it is thermally fixed by a xenon lamp. At this time,
The shielding means 60 covering the front surface 90 of the master image fixing means 9 is driven so that the window 61 is aligned with the front surface 90, and becomes temporarily open.

The master image 5 thus fixed on the image carrier 2''
2 faces the magnetic latent image forming means 11 as shown in FIG. 4(e). Then, it is permanently magnetized by the magnetic head 50 constituting the magnetic latent image forming means 11. At this time,
Since the photosensitive layer 31a itself is a non-magnetic material, it is not magnetized, and only the master image 52 is magnetized.

In this way, the magnetized master image 53 is formed on the image carrier 2 while the drum 7 makes one first revolution, that is,
A magnetization pattern is formed as a magnetic latent image.

The image carrier 2 continues to be rotated, but after 2 rotations 1'', it is rotated at a high speed at the second speed V2.

Then, when the magnetized master image 53 moves to the second developing means 6, the second magnetic developer T2 is affected by the magnetic force of the master image 53, as shown in FIG. 4(f). It is attracted and adheres to the surface of the master image 53, forming a transferred image 54.

The second magnetic developer T2 is attracted to the master image 53 by magnetic force, and therefore does not necessarily need to be charged. Further, after the transferred image 54 is developed, it is given a negative charge by being subjected to corona discharge from the pre-transfer charging means 7, as shown in FIG. 4(g).

On the other hand, the paper P is fed into the image transfer section 14 via the pair of aligning rollers 17, and the paper P is sandwiched between the transfer belt 43 and the image carrier 2. Since a bias pressure having a polarity opposite to that of the corona of the pre-transfer charging means 7 is applied to the transfer belt 43, the transferred image 54 is applied as shown in FIG. 4(h).
are electrostatically transferred onto the paper P one after another.

The paper P after the transfer is peeled off from the image carrier 2 as the transfer belt 43 runs and is sent to the fixing means 18, where the image is fixed by being heated and pressurized at the same time. The paper is discharged onto the paper discharge tray 15 via the paper discharge roller pair 19.

Note that if the second magnetic developer T2 can be sufficiently charged during development by using a triboelectrically charged toner, the pre-transfer corona discharge by the pre-transfer charging means 7 can be omitted. be. However, in order to ensure electrostatic transfer in a short time, such as when high-speed transfer is required, it is necessary to give sufficient charge to the second magnetic developer T2 by performing corona discharge before transfer. Good.

In order to continue to make second and subsequent copies from the same original in this printing mode, the transferred image forming step shown in FIG. 4(f), the pre-transfer corona discharge step shown in FIG. 4(g), and the fourth By repeating the transfer process shown in Figure (h) at the second speed (2), it is possible to make any number of copies of the same content. In other words, after forming the magnetized master image 53 on the special image forming member 2, a charging step shown in FIG. 4(a), an exposure step shown in FIG. 4(b), and a step shown in FIG. 4(c) are performed. The developer image forming process (unfixed master image forming process) shown in FIG.
) and the master image magnetization step shown in FIG. 4(e) are not required at all. Electric power required for charging, image exposure, etc. can be applied to the fixing means 18. Therefore, not only can power be saved, but also the printing mode can be performed at a high rotational speed V2 after the magnetized master image 53 is formed, so that the copying speed can be significantly increased.

Furthermore, the greater the number of copies made from the same document, the lower the cost per copy.

In addition, in order to prevent the photosensitive layer 31a from being charged due to residual charges after the second rotation of the image carrier 2 in the printing mode described in 1., the static elimination lamp constituting the static elimination means 10 is preferably turned off. Good. Some I+i4. depending on print mode.
When the duplication of multiple copies of the original is completed, the photosensitive belt 31 of the image carrier 2 is replaced with a new one. That is, the winding core 33 rotates, and the fixed size of the master image 53 is wound onto the winding core 33, and the unused new length is wound onto the non-magnetic drum 30''. is brought out.

Next, a copy mode suitable for copying a small number of sheets will be explained.

The copy mode differs from the print mode described above in that a master image is not formed. That is, as in the print mode, as the document reading device 22 starts reading the document, the image carrier 2 rotates and the charging device 11 starts to read the document as shown in FIG. 4(a). The photosensitive layer 31a is uniformly charged.

Then, as shown in FIG. 4(b), the laser beam g
is irradiated onto the photosensitive layer 31a, and electrostatic latent images corresponding to the original image are successively formed. The electrostatic latent image obtained in this way is
The image is visualized by facing the developing means 6. Since development using magnetic force cannot be performed in this copying mode, the second magnetic developer T2, which is positively charged by frictional charging or the like, is electrostatically applied ( =J to obtain a developer image corresponding to the image.Subsequently, the image carrier 2 is rotated, and after being charged by corona discharge by the pre-transfer charging means 7, a second magnetic developer is applied. The agent T2 is transferred onto the paper P one after another.The paper P after the transfer is fixed by the fixing means 18 in the same way as in the print mode, and then is discharged to the paper discharge tray 15''.

After the developer T2 remaining on the photosensitive layer 31a after the transfer is neutralized by the static eliminating means IO, the image carrier 2 is further transferred to the next one.
During rotation, the particles are brushed off by the magnetic brush effect in the second developing means 6 and collected into the second developing means 6. That is, the copying mode of this apparatus employs a two-rotation/one-copy system using magnetic brush cleaning. In this copying mode, the same photosensitive surface of the photosensitive belt 31 is used repeatedly, for example, about 1000 times, and when a predetermined number of times is reached, it is replaced with a new, unused surface.

[Effects of the Invention] According to the recording apparatus according to the present invention, since the operating portion of the fixing means is shielded by the shielding means except when the master image fixing means fixes the master image on the image carrier "2", the first It is also possible to prevent contamination of the action area due to adhesion of the second developer.

Therefore, it is possible to prevent the performance of the master image fixing means from deteriorating and to perform stable printing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing the relationship between the master image fixing means and the shielding means in an embodiment of the recording apparatus according to the present invention, and FIG. 2 is a perspective view of the recording apparatus according to the present invention. FIG. 3 is a diagram showing the entire embodiment, FIG. 3 is a diagram showing the periphery of the drum of the same embodiment, and FIG. 5 is a diagram showing the printing process in the same embodiment in order. DESCRIPTION OF SYMBOLS 1...Recording device, 2...Image carrier, 3...Charging means, 4...Electrostatic latent image forming means, 5...First developing means, 6...Second Developing means, 7... Pre-transfer charging means, 8... Transfer means, 9... Master image fixing means, 1
0... Static elimination means, 11... Magnetic latent image forming means, 60
...Shielding means, 61... Window applicant's agent Patent attorney Takehiko Suzue - 〇

Claims (1)

[Claims] a moving image carrier; a writing device for forming an image on the image carrier using a first developer containing a magnetic material capable of permanent magnetization; and a mastering device for mastering the developer image formed by the writing device. a fixing means for fixing the master image as an image; a magnetic latent image forming means for forming a magnetic latent image on the image carrier by magnetizing the developer of the master image; and a magnetic second developer for fixing the magnetic latent image. A recording device comprising: a developing means for developing the second developer image; and a transfer means for transferring the second developer image onto a transfer material; A recording apparatus characterized in that the shielding means shields an operating part of the fixing means except when fixing a master image on an image carrier.