JPS63188159A - Component type color image forming device - Google Patents

Abstract

PURPOSE:To obtain a color image forming device superior in general usefulness by constituting an image exposure optical system unit, a toner image forming unit, and a copy paper supply unit as independent bodies respectively and combining these units to form one image forming device. CONSTITUTION:An image exposure optical system unit A provided with a color exposure optical system, a toner image forming unit B provided with an image forming unit group freely movably to set one image forming unit of the image forming unit group to the toner image forming state, and a copy paper supply unit C which supplies copy paper to the unit B are constituted as independent bodies respectively, and these units are combined to form one image forming device. Since respective component of the image forming device are constituted as unit bodies A, B, and C, the general usefulness as the color image forming device is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an image forming apparatus, and more specifically to an exposure section, a toner image forming section, and a toner image forming section that constitute the image forming apparatus.
The present invention relates to a component type color image forming apparatus in which a copy paper feeding section is configured separately.

(Prior Art) Many color image forming apparatuses such as full-color PPCs and color printers have been proposed. As for image creation formats, many methods have been adopted, including electrophotography, inkjet, and thermal transfer.

Among these, electrophotographic color copying machines are attracting attention from the viewpoint of image quality and production speed.

By the way, a color copying machine that uses an electrophotographic method is equipped with a four-color developing device that has black added to the three primary colors of cyan, yellow, and magenta, and is also used for color matching when the process is repeated many times. Since a transfer drum is used for this purpose, the mechanism is generally complicated as described in 4).

Therefore, although many color copying machines have a monochromatic mode and are capable of producing monochromatic copies, they have only been used as color-only machines.

(Problems to be Solved by the Invention) The above-mentioned color-only machine has a problem in that the copying speed is slow and impractical when attempting to obtain monochrome copies.

Furthermore, in order to obtain monochrome copies, a monochrome copying machine separate from the color machine was often used.

Furthermore, the versatility of being able to freely select analog or digital exposure formats using a single color copying machine was lacking.

(Object of the Invention) The present invention was discovered in order to solve the above-mentioned problems, and an object of the present invention is to provide a color image forming apparatus with excellent versatility.

Another object of the invention is to provide a color image forming apparatus that can perform the same functions as a monochrome-only image forming apparatus when producing monochrome copies. do.

(Structure of the Invention) In order to achieve the above object, the present invention provides a component-type color image forming apparatus including: (i) an optical system unit for image exposure equipped with a color exposure optical system; (ii) a unit for charging, developing, cleaning, etc. A group of image forming units in which a plurality of image forming units in which at least one image forming means is arranged around the circumference υ■ of a photoreceptor drum is arranged in correspondence with the number of desired basic colors, and a copy paper is conveyed. the image forming unit group is provided movably so that one of the image forming unit groups is in a toner image forming state; The line of movement, the copy paper conveyance path, and the peripheral surface of the transfer drum are in line contact or in a state close to it in the transfer area for transferring toner from the image forming unit in the toner image forming state onto the copy paper. (i) to (iii) a copy paper feeding unit for supplying copy paper to the production unit; ) are combined to form one image forming apparatus.

(Action of the invention) As described above, each component of the image forming apparatus (i)
By configuring the color image forming apparatus as a plurality of units (iii), the versatility of the color image forming apparatus is improved as described below.

For example, if the color toner image forming unit shown in configuration (ii) above is used as the core and is combined with a unit body in which the color exposure optical system is of an analog type or digital type, a color image forming apparatus of any type can be formed. can.

Furthermore, various 81 functions can be added by changing the conveyance unit to one for high speed, low speed, or double-sided copying.

Furthermore, the core color toner image forming unit is
Since the transfer drum is positioned in line with or close to the normal copy paper conveyance path, when making monochrome copies, image formation can be performed without going through the transfer drum, greatly increasing the monochrome color copying speed. improve. Then, it is possible to perform high-quality full-color copying without color shift by using the transfer drum only when full-color copying is necessary.

(Example) The present invention will be explained below based on the accompanying drawings.

FIG. 1 is a schematic diagram showing a component type color image forming apparatus of the present invention. The component-type color image forming apparatus as a whole, indicated by 2, includes, from the top of the figure, a color image exposure optical system unit A1, a toner image forming unit B1 below it, an intermediate tray unit D for double-sided copying below it, and a bottom part. (Two copy paper supply units) El
, E2).

Each of these units is stacked in a predetermined positional relationship by a positioning mechanism 1 provided on the top surface of each unit, forming one image forming apparatus W2.

For example, the color image exposure optical system unit) A is
4 and a color image optical system having a known color separation function using filters and the like. In the actual exposure, a color original (not shown) placed on the original placing part 4 is scanned and exposed with a light source 5 having an emission spectrum over the entire visible light range, The document surface is guided to the optical system 6 as an optical light spot. In this optical system 6, cyan and yellow.

The light is separated into specific color light using a color separation filter such as magenta, and the separated light is guided to the toner image forming unit B by an inter-exposure lower provided on the lower surface of the unit.

The toner image forming unit B has an exposure opening 10 provided on the upper surface of the unit housing 8 in a positional relationship corresponding to the lower part of the unit during exposure. Three image forming units 12, 14, and 16 equipped with cyan, yellow, and magenta colored toners are arranged horizontally in a line so as to be movable in the horizontal direction, with the hanging portion of the exposure aperture 10 as the operating position for image formation. has been done.

The three image forming units 12, 14, and 16 have basically the same structure except that the toner colors are different.

Specifically, a main charger 13, a developer 15 having colored toner, and a cleaning device 17 are arranged in this order around the photosensitive drum 11. The top and bottom positions of the drum 11 of the image forming unit 12 are exposed as an exposure area and a transfer area.

Among the exposure areas of these three image forming units 12, 14, and 16, the image forming unit (unit 14 in the figure) corresponds to the position corresponding to the exposure opening IO of unit B.
is the operating position.

A transfer drum 18 is rotatably provided in the hanging portion of the transfer area T of the image forming unit 14 located in this operating position, and a transfer drum 18 is provided inside the transfer drum 18 at a position corresponding to the transfer area T. A charger 19 is provided. A copy paper transport path 20 extending from the lower right to the lower left in the figure is formed so as to largely surround the transfer drum 18. More specifically, the first paper feed conveyance path 20a from the manual paper feed port 22 provided on the lower right side surface of the housing 8 of unit B to the transfer area T, and the lower surface of the housing 8 in the figure. There is a second paper feed conveyance path 20b leading from the automatic paper feed opening 24 provided on the side stand to the transfer area T. The fixing device 26 is provided at the fixing device 26 .

The copy paper that has passed through the conveyance path 20 and the fixing device 26 is
The liquid is discharged from the unit B through a discharge opening 28 provided on the left side of the housing 8 of the unit B. The ejection tray 27 may be directly installed in the ejection opening 28 (or, an intermediate tray unit D for double-sided copying as shown in the figure may be disposed below the unit B, It is also possible to form a W1 loop path 30 leading to the automatic paper feeding opening 24.

In detail, this intermediate tray unit D is a unit body formed as an abbreviated housing body that can be connected to two openings, the discharge opening 28 and the automatic paper feeding opening 24 to the unit. be. A first conveyance path 38 is formed in the discharge opening 28 of the unit B, which leads from an opening 29 provided at a position corresponding to the opening 28 to a paper discharge port 31 provided on the left side of the unit D. ing. A switching lever 40 is provided at an intermediate position of this conveyance path 38, and a first conveyance path leading to a circulation path 30 for guiding (to) an intermediate tray 36 provided at the center of the unit D and a paper discharge port 31 is provided. Furthermore, on the paper discharge port 31 side of this conveyance path, there is a pair of rollers 3 that can rotate in forward and reverse directions.
9 is provided to eject copy paper and transport it for double-sided copying.

Further, a pair of rollers 44 that can rotate in forward and reverse directions is provided in the circulation path 30. Now, by switching the switching lever 40 toward the circulation path 30 and rotating the roller pair 44 in the normal direction,
The copy paper that has left the fixing device 26 is once delivered to the intermediate tray 36 W
The copy paper is guided to the fourth ring path 30, and the rear end of the copy paper is connected to the switching lever 40.
Immediately after passing through, the roller pair 44 is reversed. As a result, the copy paper is guided to the paper discharge port 31 by the reverse action of the roller pair 44, with the rear end of the copy paper located near the switching lever 40 now being the leading edge. Due to this reversal effect, the front and back sides of the copy paper are reversed, and the paper is ejected with the side facing up, which is different from when it is used directly. Therefore, by using the switching lever 40, the front and back sides of the copy paper can be freely discharged.

On the other hand, when performing double-sided copying, the copy paper is guided once to the first conveyance path 38 by using the switching lever 40, the forward/reverse rotatable roller 39 located near the paper ejection port 31, and the intermediate tray 36. This can be done freely by switching back the copy paper using the forward and reverse rotatable roller 39 and circulating the copy paper to the intermediate tray 36 while changing the front and back sides by the switchback.

Note that an opening 51 is provided on the lower surface of the housing 8 of this unit D to enable conveyance of copy paper automatically fed by the paper feeding unit C-IJ, which will be described later. A bypass passage is formed from the housing 8 to an opening 24 provided in the lower surface of the housing 8 of the unit B.

Next, copy paper feed unit 1. TE2 will be explained. Paper feed Uniso I-IEI and E2 basically have the same structure; for example, El automatically feeds relatively large size copy paper, and E2 automatically feeds relatively small size copy paper. unit.

Specifically, a paper feed cassette 50 disposed on the left side of the figure, a paper feed roller 52 provided in the paper feed cassette 50 for feeding copy sheets one by one, and A paper feed passage 56 provided on the right side of the upper surface of units E1 and E2 and leading to the automatic paper feed opening 24 of units T3 to D or the bypass passage artificial opening 51, and a bypass similar to that provided in unit D. It is composed of a passage 58.

In the color image forming apparatus described above, the y
The important features of Jl are Uni7) A, B based on the functions each image forming device has.

The image forming apparatus is divided into D and C, and these are combined as necessary to form a single image forming apparatus. in this way,
By forming an image forming apparatus into a unit, if A and C are combined with toner image forming unit B as the core, an analog image forming apparatus can be obtained. Take A again.

If it is combined with C, an analog image forming apparatus capable of double-sided copying can be obtained.

On the other hand, if the exposure optical system unit 8 is replaced with a digital exposure unit A' that uses a laser as a light source and a polygon mirror deflector, it becomes possible to function as a digital color printer.

In this way, it is possible to provide an image forming apparatus with great versatility.

Moreover, since each unit is provided with the positioning mechanism 1, no matter how the units are combined, the respective openings can be smoothly connected and each function can function effectively.

The second feature of the present invention is the transport path 20 of the color toner image forming unit B. That is, the conveyance path 20 is formed to pass through a transfer area T formed between the transfer drum 18 and a group of image forming units (12, 14, 16) arranged in a line.

With this configuration, when performing monocolor 131'lp, the copy paper is moved along the conveyance path 20, and the color toner from the image forming unit containing appropriate color toner is transferred to the transfer area 'r. can be transferred to the fixing device 26 through the conveying path 20 as it is. As a result, monochrome copying can be performed without involving a transfer drum, so that although it is a color copying machine, toner images can be formed at the same high speed as a normal copying machine.

When performing full color printing, while transferring the copy paper passing through the conveyance path 20 with the first color toner,
The copy paper is fixed on the transfer drum 18 using a fixed guide bin 100 provided on the transfer drum, and the copy paper is fixed on the transfer drum 28.
The toner image of each color is transferred multiple times in accordance with the rotation of the drum. After the desired color toner image has been transferred, the fixed guide bin 100 is released and the copy paper is removed from the transfer drum 18 and conveyed again. Feeding unit 2 to path 20
As a result, it is possible to use a transfer drum only when full color or a plurality of colors are used. Moreover, by synchronously controlling the rotation of the transfer drum and the cycle of the toner image forming process, it is possible to reliably obtain a color copy without color misregistration.

(Effects of the present invention) According to the present invention, while having the functions of a color image forming apparatus, it is possible to perform high-speed copying without using a transfer drum in the case of a single color, and only in the case of color image formation. Copies without color shift can be obtained using a transfer drum.

Furthermore, by adopting a component format, the image forming apparatus can be used as a versatile image forming apparatus.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing a component type color image forming apparatus of the present invention, and the numbers in the figure represent the following contents. 1... Positioning mechanism 2... Component type color image forming device 12.1
4.16... Image forming unit 18... Transfer drum 20... Conveyance path A... Optical system unit for color image exposure B... Toner image forming unit D... Intermediate tray units El, E2 ...Paper feed unit T...Transfer area

Claims (2)

[Claims] (1) Optical system unit for image exposure equipped with a color exposure optical system; An image forming unit in which at least one of image forming means such as charging, developing, and cleaning is arranged around a photoreceptor drum is the desired basis. The image forming unit includes a plurality of image forming unit groups arranged in correspondence with the number of colors, a copy paper conveying path for conveying copy paper, and a transfer drum, and one of the image forming units in the image forming unit group is An image in which a group of image forming units is movably provided so that a toner image is formed, and the movement line of the image forming unit, the copy paper conveyance path, and the circumferential surface of a transfer drum are in a toner image forming state. a toner image forming unit positioned in a line tangent or close to the transfer area for transferring toner from the forming unit onto the copy paper; and a copy paper feeder for supplying the copy paper to the toner image forming unit. A component-type color image forming apparatus characterized in that: a feeding unit; and a feeding unit are each configured separately, and these units are combined to form one image forming apparatus. (2) A photosensitive drum that forms and holds a toner image compatible with color image exposure, a transfer drum that transfers and holds the toner image onto copy paper temporarily held on its circumferential surface, and transport for the copy paper. the peripheral surface of the photosensitive drum, the copy paper conveyance path, and the peripheral surface of the transfer drum are in line contact or in a transfer area for transferring toner from the photosensitive drum onto the copy paper; A color image forming apparatus characterized by being positioned in a state close to that.