JPS60177370A - Polychromatic copying machine - Google Patents

Abstract

PURPOSE:To improve the transfer efficiency during monochromatic copying operation by using different form conveyance paths in polychromatic copying operation and monochromatic copying operation. CONSTITUTION:The conveyance path for a form 6 is provided with a timing roll 20 which carries the form 6 taken out of a form cassette 9 to a transfer drum 7, a vacuum conveyance path 22 which is used during the polychromatic copying operation so as to convey the form 6 separated from the transfer drum 7 to a fixing device 21, and a vacuum conveyance path 23 which is used during the monochromatic copying operation. In regard to a photosensitive drum 2 which is charged electrostatically uniformly an original is exposed through one of color separation filters during the polychromatic copying operation to form a color image charged latent image, which is developed by a developing device 5. The transfer drum 7 is placed in a stationary state during the monochromatic copying operation and the opening part 10 is used opposite to the side of a transfer corotron 15 and a destaticizing corotron 16 and the form 6 after an image is transferred is guided to the vacuum conveyance path 23 for the monochromatic copying operation with a separation claw 8 and carried to a fixing device 21.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multicolor copying apparatus using electrophotography. More specifically, the present invention relates to a multicolor copying apparatus that can perform monochrome copying and improve transfer efficiency during monochrome copying.

(Prior Art) Conventionally, a multicolor copying apparatus using the Shimiko photography method is equipped with a plurality of color separation filters in the vicinity of a rotating photosensitive drum and a developing device having a developer having a complementary color relationship with the filters. The original image is spectral exposed on the photosensitive drum using the color separation filter, and the obtained color charge latent image is developed with a developer having a color complementary to that of the filter, and then transferred onto paper. A multicolor copy image is obtained by sequentially repeating and overlapping transfer for each filter.

To explain the copying device in more detail, the transfer device is configured with a transfer drum that is close to the photosensitive drum and rotates in the opposite direction with respect to the photosensitive drum, and accurately superimposes the copied images formed for each color separation filter. It works like that. That is, 1
The paper onto which the colored toner image has been transferred is held by a gripper provided on the transfer drum, rotates together with the drum, and is conveyed to a transfer position so that the toner image formed in the next process is superimposed on the paper.

However, when trying to perform monochrome copying using black toner or single color toner using the multicolor copying apparatus configured as described above, the paper on which the image has been transferred continues to be held by the transfer drum and moves, resulting in multicolor copying. Since the copying machine passes through the same conveyance path as the copying machine, it has the disadvantage that the transfer speed is slower than that of a copying machine with the same process. In particular, when making multiple copies of a single original, the number of copies per hour is extremely small.

(Object of the Invention) Therefore, an object of the present invention is to provide a multicolor copying device that eliminates the above-mentioned drawbacks in a multicolor copying device and can increase the number of copies by increasing the transfer efficiency during monochrome copying. It's about doing.

(Structure of the Invention) That is, the above-mentioned object of the present invention is to provide a multi-color copying apparatus which obtains a copy image by developing a color charge latent image formed on a photosensitive drum and repeatedly transferring the charged latent image onto a sheet of paper. In the
This is achieved by a multicolor copying apparatus characterized in that different paper transport paths are used during multicolor copying and monochrome copying.

(Example) Hereinafter, an example of implementation of the present invention will be described in detail using the drawings.

FIG. 1 is a schematic diagram of a multicolor copying apparatus according to the present invention.

The multicolor copying device (1) includes a charging device (3) that uniformly charges the surface of a photosensitive drum (2) that rotates counterclockwise, and a charging device (3) that spectrally transfers a document image onto the charged photosensitive drum (2). an exposure section (4) equipped with a plurality of color separation filters that are exposed to light to form a color image charge latent image; and a developer having a complementary color relationship with each of the color separation filters to visualize the color image charge latent image. A plurality of developing devices (in order to simplify the drawing, two developing devices are shown in this embodiment) (5), and the visualized color charge latent image is transferred onto a sheet of paper (6). The transfer P ram (force), which is rotatable in the clockwise direction for transfer, and the separation claw (8) for separating the paper (6) from the surface of the photosensitive drum (2) during monochrome copying, and the cleaning device (9) are sequentially brought close to each other. The transfer drum (formed in a substantially hollow cylindrical shape with a mesh-like insulating material (14) stretched around its circumferential surface, and has an opening (10 ) is provided.

In addition, the transfer drum (within the opening αO1)
A transfer corotron Q51 and a static elimination corotron (16) are provided in sequence along the rotational direction (clockwise) of the transfer drum (7), and are provided so as to constantly rotate to the surface of the photosensitive drum (2) and emit ions. There is. Furthermore, the transfer drum (having a gripper (1) for holding the paper (6) on the outer peripheral surface of the paper (6) in the direction of rotation that lags behind the opening (10); Close to the inner peripheral surface of the force,
a grip cam (2) for releasing the gripper (17) into a position for holding the paper (6) on the transfer drum (7);
Seasons are arranged. Furthermore, a release cam 0 barrel is disposed at a position on the inner circumferential surface of the transfer drum (force) to release the paper (6) from the transfer drum (the gripper 07 in order to separate it from the force).

Next, a paper cassette a9 is placed on the transport path for the paper (6).
A timing roll (20) that transports the paper (6) removed from the transfer drum (7), and a multicolor copying machine that transports the paper (6) released from the transfer drum (7) to the fixing device (21). A vacuum conveyance path (221) used at times and a vacuum conveyance path (2) used at the time of monochrome copying are provided respectively.
9 and 28) each have an introduction portion close to the outer peripheral surface of the transfer drum (7), and those for monochrome copying are provided closer to the transfer position than those for multicolor copying. The one for copying is installed near the location where the release cam 0 barrel is installed.

Furthermore, a transfer separation claw (25) for guiding the paper (6) from the transfer drum (7) to the vacuum conveyance path (22)K is provided at the introduction part of the vacuum conveyance path (22+) for multicolor copying.

Next, the copying process of the multicolor copying device (1) will be explained. During multicolor copying, the uniformly charged photosensitive drum (2) is exposed to light through one of the color separation filters, and a color image is formed on the photosensitive drum (2). A latent charge image is formed. Further, the color image charge latent image is developed by a developer (51) having a color toner complementary to the color of the color separation filter, and is moved to a transfer position facing the transfer drum (7). The paper (6) taken out from the paper cassette (1!111) is conveyed to the transfer drum (sumo wrestler) by the timing roll (20), and transferred by being held by the rotating transfer drum (power gripper (17)). The image is transferred to the transfer corotron (transfer corotron 05).At this time, the voltage applied to the transfer corotron (corotron 05) is transferred to the transfer drum (the mesh-like insulating material (1
4). As mentioned above, when the voltage is applied through the mesh-like insulating material (14+), the insulating material 04 slightly peeks out and attracts the paper (6), so the TjiJ transfer drum This works well for the paper (6) that is held and conveyed.

The transfer drum (6) holding the image-transferred/ζ paper (6)
7) rotates once, and the photosensitive drum is gone! 21 is the table [II
] is cleaned by the cleaning group M(9), the first imaging cycle is photonized. In this way, the image creation process is repeated for each of the other color separation filters, and each color image is placed on the paper (6).
As the multicolor copy image is formed by being superimposed on the paper, the paper (
6) is carried to the installation location of the release cam (country). At the installation location of the above-mentioned IJ IJ-scum (18), the release cam bet, which had been placed in a position where it did not act on Grishi/1!-(17+), moves in a radial outward direction and presses the grating plate (2)'-f171, and the transfer separation claw (251) operates to move the paper (6) onto the transfer drum (251).
The vacuum conveyance path (22
I will guide you to 1. The paper (6) carried by the vacuum conveyance path (24) is conveyed to a fixing device (21), and the unfixed image is fixed thereon.

Next, to explain the copying process during monochrome copying, the transfer drum (7) is placed in a stationary state without rotating, and the opening (10) is directed toward the transfer corotron 05) and static elimination corotron (16). used. That is,
The paper (6) carried by the timing roll (20)
) is the transfer corotron (15) and static elimination corotron 0.
6) After passing through the c21 and the image is transferred, it is guided by the separation claw (8) to the vacuum conveyance path (23) for monochrome copying, and moves along the vacuum conveyance path (23) to the fixing device c21.
).

During this monochrome copying, the paper (6) is transported only by the timing roll (Paulownia) and the vacuum transport path (231), so the introduction part of the vacuum transport path (23) is The conveyance path (22) is also located close to the transfer position and approximately tangential to the photosensitive drum (2) and transfer drum (7), so that it can be fixed in a short path even in multicolor copying machines. be done.

As explained above, in the present invention, in order to improve transfer efficiency during monochrome copying, the transfer drum (7) is not substantially used and a shorter paper conveyance path is used than during multicolor copying. In this case, the transport paths for the paper (6) are provided independently.

(Effects of the Invention) As described above, according to the multicolor copying apparatus of the present invention, since the transfer drum does not rotate during monochrome copying,
The transfer speed can be increased and the number of sheets per saw can be increased without being affected by the rotation of the transfer drum.

Further, since the paper is not held by the gripper during monochrome copying, image loss does not occur in the portion corresponding to the grit j-holding portion during multicolor copying.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a multicolor copying apparatus according to an embodiment of the present invention. Code in the figure:

Claims (1)

[Claims] In a multicolor copying device that obtains a copy image by developing a color charge latent image formed on a photosensitive drum and repeatedly transferring it onto a sheet of paper, there are differences between multicolor copying and monochrome copying. A multicolor copying device characterized by using a paper conveyance path.