JPH04165376A - Color image forming device - Google Patents

Abstract

PURPOSE:To facilitate the maintenance by connecting in a detachable manner a plurality of image forming units and a paper supply unit to each other in the carrying direction of transfer paper. CONSTITUTION:Each picture forming unit 1 is comprised of rows of array-like LED elements which are arranged along the axial direction on the inner periphery side of a photosensitive body drum 2, a developing means 3 and a transfer means 5 both arranged on the outer periphery side of the photosensitive body drum 2 and a pair of carrier rollers 11 provided on the downstream side of the transfer means 5, and is defined as the one unit, and also a paper feed unit 14 having a feed paper roller 9 and regist rollers 6 is provided upstream of transfer paper of the unit 1. A plurality of the image forming units 1 and the feed paper unit 14 are connected in a detachable manner to each other in the carrying direction of the transfer paper. With this constitution, the maintenance work for each unit is facilitated.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention relates to the formation of an image on the inner peripheral side of a photoreceptor drum, which is formed by laminating a light-transmitting conductive layer and a photoconductor layer on a light-transmitting support. Related to an image forming apparatus equipped with an exposure means for use [Prior art] Conventionally, on the inner circumferential side of a photoreceptor drum, which is formed by laminating a light-transmitting conductive layer and a photoconductor layer on a light-transmitting support, a developing means disposed facing the photoreceptor drum at the same time as or immediately after converging light output corresponding to image information to form a latent image on the photoelectric layer (hereinafter referred to as optical back exposure method); An image forming apparatus is known that is configured to convert the latent image into a visible image (toner image) via a transfer roller or other transfer means, and then transfer the toner image onto plain paper via a transfer roller or other transfer means. (Unexamined Japanese Patent Publication No. 5
8-153957, etc.) Among such devices, a device for forming a multicolor image has also been proposed. (For example, JP-A-2-1
98466) [Technical problem to be solved by the invention] However,
A color image forming apparatus using the optical back exposure method consists of a charging means, an exposure means provided inside a transparent photoreceptor, and a developing means as a set, and multiple sets of these are sequentially arranged to perform recording. This is what we do.

Therefore, the photoreceptor itself must be equipped with a plurality of exposure means such as LEDs, and a large number of developing devices must be arranged around the photoreceptor, which inevitably increases the size of the photoreceptor and the entire device. The structures of other process means and devices become complicated, and the overall size of the device increases.

In particular, it is difficult to take full advantage of the advantages of the electrophotographic process, which requires an exposure means inside the photoreceptor and fewer process means, as in the optical back exposure method mentioned above, and when maintenance is taken into account, there are many exposure means inside the photoreceptor drum. It becomes more troublesome to narrow down the information.

In view of the drawbacks of the prior art, it is an object of the present invention to provide a novel color image forming apparatus that takes advantage of the features of the optical back exposure method and is easy for users to handle and maintain.

[Technical means for solving 81NK] The first invention is:
In order to achieve this technical problem, as shown in Examples below, an array-like structure is formed on the inner circumferential side of a photoreceptor drum made by laminating a light-transmitting conductive layer and a photoconductor layer on a light-transmitting support. An image forming unit is constructed by arranging an array of LED elements along the axial direction, a developing means and a transfer means on the outer peripheral side of the photoreceptor drum, and a pair of conveying rollers on the downstream side of the transfer means. A paper feeding unit having a paper feeding roller and a registration roller is provided on the transfer paper upstream side of the unit, and the plurality of image forming units and the paper feeding unit are removably connected in the transfer paper conveyance direction to produce a color image. A forming device was constructed.

In addition, the present jI2 invention provides an arrangement in which an array of LED elements is arranged along the axial direction on the inner peripheral side of a photoreceptor drum formed by laminating a transparent conductive layer and a photoconductor layer on a transparent support. A developing unit and a transfer unit are arranged on the outer circumferential side of the photosensitive drum, and a pair of conveying rollers is provided downstream of the transfer unit. A color image forming apparatus was constructed by providing a paper discharging unit having a heating fixing roller and a paper discharging section, and connecting the plurality of image forming units and the paper discharging unit removably in the transfer paper conveyance direction.

In this way, one image forming unit and an independent paper feeding unit,
By providing the paper ejection unit, maintenance of each unit becomes easier.

Further, by connecting a plurality of image forming units in series in the direction of the transfer paper between the paper feed unit and the paper discharge unit, it is possible to form any image from monochrome to multicolor.

[Embodiments] Hereinafter, embodiments of the present invention will be explained in detail by way of example based on the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in this example are merely illustrative and do not limit the scope of the invention, unless otherwise specified. Just an example.

1 is a schematic explanatory diagram of an image forming apparatus showing a first embodiment of the present invention, and a second EII is a schematic explanatory diagram showing a second embodiment. Note that the same parts are given the same numbers.

1 indicates each image forming unit 6 Each unit 1 is independently configured as a unit capable of developing each color necessary for color such as yellow, magenta, cyan, and black.

2 is a photosensitive drum provided in each unit 1;
The photosensitive drum 2 is formed by laminating a transparent conductive layer and a photoconductor layer on a drum-shaped transparent support, and is rotatably attached to the unit 1 in the direction of the arrow by a drive roller (not shown).
is attached to.

3 is a developing device; 4 is an exposure unit inserted into the photosensitive drum 2; the LED array generates light output corresponding to image information on a support made of a non-transparent insulating material; An exposure system consisting of a self-focusing lens (trade name: SELFOC lens) is fixedly arranged and extends over the entire area in the axial direction of the photoreceptor.

The image forming position of the exposure system is configured to form an image on a photoelectric layer located on a line connecting the axes of the photosensitive drum 2 and the developing sleeve 3a in the developing device 3.

The developing device 3 includes a toner container 3 that stores conductive magnetic toner.
The side facing the photoreceptor drum 2 of b is open, a developing sleeve 3a containing a fixed magnet assembly is disposed in the opening, and the layer thickness of the toner is regulated by a doctor blade 3c formed on the side of the toner container 3b. is guided to a development position corresponding to the image formation position of the exposure system, and after developing the latent image formed on the development position, the toner image carried on the photosensitive drum 2 is transferred to the rotation of the drum 2. The toner image is guided to the transfer roller 5 side, and the transfer roller 5 transfers the toner image onto the plain paper that has been pushed through with timing by the registration roller 6. After the transferred unfixed toner image is fixed by the fixing roller pair 7, The paper is ejected onto the paper ejection tray 8.

On the other hand, the photosensitive drum 2 after the toner transfer is guided to a developing position, and after removing residual toner by rubbing with the toner just before the developing position, the above operation is repeated.

Note that 9 is a paper feed roller that guides the plain paper stacked in the paper feed cassette 10 to the registration roller 6.

Reference numeral 11 denotes a pair of conveyance rollers for conveying the transfer paper onto which the toner image has been transferred by the transfer roller 5 to the next unit 1. The pair of conveying rollers 11 is composed of rubber rollers whose surface has been treated with a Teflon coat or the like having releasable properties, and the unfixed toner images are temporarily attached by the pressure contact force of the rollers, so that the color images are successively transferred. Color mixing during formation can be prevented.

As described above, the image forming unit 1 includes a drum 2, a developing device 3, an exposure unit 4, a transfer roller 5. Built-in IIi feed roller pair 11, paper insertion openings 1 on the upstream side and downstream side of the transfer paper
2.13.

The units 1 are constructed so that they can be attached to and detached from each other by means such as sliding or screwing so that the insertion openings 12 and 13 of each unit 1 are connected in the transfer paper transport direction.

Reference numeral 14 denotes a paper feed unit that is removably attached to the insertion opening 12 side of the unit 1, and includes a paper feed cassette 10, a paper feed roller 9, and a registration roller 6.

Reference numeral 15 denotes a paper ejecting unit that incorporates a pair of heat fixing rollers 7 and a paper ejecting tray 8 for fixing an unfixed toner image by heat fixing.

Reference numeral 16 denotes a blade that cleans the conveying roller pair 11 when toner adheres thereto.

FIG. 2 shows a second embodiment of the present invention. In this embodiment, the developing device 3 is provided below the photoreceptor drum 2, and the transfer roller 5 is provided above the photoreceptor drum 2. is configured as the upper surface of the photoreceptor drum 2.

As in this embodiment, the developing means is provided in the unit 1,
When placed below the photoreceptor drum 2, toner that does not contribute to the development process will not adhere to the transfer paper, so that the image will not be stained.

[Effects of the Invention] As described above, according to the present invention, a paper feeding unit having a paper feeding roller and a registration roller is removably provided on the transfer paper upstream side of an image forming unit, and a transfer paper of one image forming unit is provided. By removably providing a paper discharge unit having a heating fixing roller and a paper discharge section on the downstream side, it is possible to connect these units and an independent image forming unit in series in the transfer paper conveyance direction. Both image forming apparatuses can be configured with easy maintenance.

[Brief explanation of drawings]

FIG. 311 is a schematic explanatory diagram of an image forming apparatus showing a fifth embodiment of the present invention, and FIG. 2 is a schematic explanatory diagram showing a second embodiment. 1... Both image forming unit 14... Paper feeding unit 15... Paper ejection unit

Claims (2)

[Claims] (1) An array of LEDs is installed on the inner circumferential side of the photosensitive drum, which is formed by laminating a transparent conductive layer and a photoconductor layer on a transparent support.
An image forming unit is constituted by an image forming unit in which an array of elements is arranged along the axial direction, a developing means and a transfer means are arranged on the outer peripheral side of the photosensitive drum, and a pair of conveying rollers is provided on the downstream side of the transfer means. , a paper feeding unit having a paper feeding roller and a registration roller is provided on the transfer paper upstream side of the unit, and the plurality of image forming units and the paper feeding unit are detachably connected in the transfer paper conveyance direction. Characteristic color image forming device. (2) An array of LEDs is installed on the inner circumferential side of the photosensitive drum, which is formed by laminating a transparent conductive layer and a photoconductor layer on a transparent support.
One unit is an image forming unit in which an array of elements is arranged along the axial direction, a developing means and a transfer means are arranged on the outer peripheral side of the photoreceptor drum, and a pair of conveying rollers is provided on the downstream side of the transfer means. , a paper discharge unit having a heat fixing roller and a paper discharge section is provided on the transfer paper downstream side of the unit, and the plurality of image forming units and the paper discharge unit are detachably connected in the transfer paper conveyance direction. A color image forming device characterized by: