JPS63168670A - Copying machine with selective destaticizer - Google Patents

Abstract

PURPOSE:To display an image practically in a short time even in case of the use of a display element having a low response speed to improve the copying efficiency by using a transmission type electrochromic display element, where plural segments or dots are arranged, and back light as light emitting means which selectively destaticize the electrostatic charge on the surface of a photosensitive body. CONSTITUTION:The light emitting means consists of a transmission type electrochromic display element 70 where plural segments or dots are arranged and back light, and the light of the back light 82 is selectively transmitted to a photosensitive body by this transmission type electrochromic display element 70 to destaticize the electrostatic charge. The transmission type electrochromic display element 70 used in this case is a single display element provided with plural segments or dots, and it is constituted with a low cost. Since the electrochromic display element 70 is driven to a half-tone state when a copying machine is held before the copying operation, the electrochromic display element 70 is switched from the half-tone state to the coloring state or the decoloring state in a short time to display the image in a prescribed state.

Description

DETAILED DESCRIPTION OF THE INVENTION (Al Industrial Field of Application) The present invention relates to a copying machine equipped with a selective static eliminator that can selectively erase an image by previously neutralizing a predetermined area on a photoreceptor.

(b) Summary of the Invention A copying machine with a selective static eliminator according to the present invention selectively eliminates static electricity from an electrostatic latent image formed on a photoreceptor in an electrostatic electrophotographic copying machine. A light-emitting means for selectively removing static electricity from a position on the photoreceptor where a latent image is to be formed is provided between a charging device and a developing device. By using a display element and a backlight, the area to be neutralized can be neutralized with high precision, and the response speed of the display element can be increased.

(C1 Conventional technology When copying a thick original or a document one size smaller than the standard size with the original cover open, black streak-like unnecessary images are formed on the top and bottom edges of the copied image. In order to remove such unnecessary images, a light emitting means is provided to selectively eliminate static electricity from the electrostatic latent image formed on the photoreceptor.

A light emitting diode array is used in which the light emitting means odes are arranged in a line and each light emitting diode is divided by a partition plate.

(d) Problems to be Solved by the Invention Since such conventional light emitting means is constructed by arranging a large number of light emitting diodes as described above, the assembly process is complicated and costs are high. There were drawbacks. Furthermore, the resolution of the light emitting means is determined by Sochi, and is at most 2.5 to 2.
It is about 7 mm. For this reason, there is also a problem in that the electrostatic latent image cannot be neutralized with high accuracy.

SUMMARY OF THE INVENTION An object of the present invention is to provide a copying machine equipped with a selective static eliminator, which reduces the cost of the light emitting means and improves the resolution of the area to be neutralized.

FE1 Means for Solving Problems A copying machine with a selective static eliminator of the present invention selectively removes static electricity from an electrostatic latent image formed on a photoreceptor, or removes static electricity from a photoreceptor on which an electrostatic latent image is to be formed. A copying machine is provided with a light-emitting means for selectively removing static electricity from a position in advance between the charging device and the developing device, and a charge-elimination control means for controlling the light-emitting means, wherein the light-emitting means is arranged in a plurality of segments or dots. It is characterized by comprising a transmission type electrochromic display element and a backlight, and further comprising means for driving each segment or dot of the electrochromic display element to a neutral color state during standby before a copying operation in the static elimination control means. There is.

(f) Function In the copying machine with a selective static eliminator of the present invention, the light emitting means is composed of a transmission type electrochromic display element in which a plurality of segments or dots are arranged and a backlight, and the transmission type electrochromic display element is composed of a backlight. The element eliminates static electricity by selectively transmitting backlight light to the photoreceptor. The transmission type electrochromic display element used at this time is a single display element provided with a plurality of segments or dots, and can be constructed at low cost. Display elements using electrochromic materials, which have been used in the past, generally have a response speed that is not so high compared to other display elements; Although it takes a certain amount of time, according to this invention,
Since the electrochromic display element is driven to a neutral color state during standby before a copying operation, it changes from this neutral color state to a colored state or a colorless state in a short time and displays a predetermined state. Note that a plurality of segments or dots can be arranged in this display element with a finer pitch than the arrangement pitch of a conventional light emitting diode array, and the resolution of the area to be neutralized can be improved.

(gl Embodiment FIG. 2 is a diagram showing the configuration of a copying machine to which a selective static eliminator according to an embodiment of the present invention is applied.The explanation will be given below.

A photoreceptor drum 20 is provided approximately at the center of the main body of the copying machine, and various units for executing the copying process are provided around the photoreceptor drum 20. The unit includes a charging device 212, a light emitting device 7. First developing device 2
2a, second developing device 22b, transfer and peeling charger 23. A cleaner unit 24 and the like are provided. The light emitting means 7 is a device for selectively neutralizing the surface of the photoreceptor drum charged by the charging device 21, and is composed of a backlight and an electrochromic display element, as will be described later. Reference numerals 36a, 36b, and 36c each indicate paper feeding power cents, and the paper selectively sent out from any of the cassettes is conveyed toward the photosensitive drum 20 via the registration rollers 35. The paper onto which the toner image has been transferred is fixed by a fixing roller 25 and is conveyed to the left in the figure. At this time, by the action of the claws 26 and 27, the paper is ejected as it is to the tray 31, or after being ejected to the tray 29 once, it is again conveyed in the opposite direction by the reversing roller 28, and then passed through the roller 30 to the tray. 31 and is discharged. Such selective conveyance is controlled depending on whether double-sided copying or composite copying is performed on one side of the paper. When 7 copies are made again on the paper stored in the tray 31,
By the rotation of the rollers 31a and 31b, only the topmost sheet of paper stored in the tray 31 is selectively conveyed, and then transferred to the registration roller 35 again via the rollers 32, 33, and 34.
conveyed in the direction.

As described above, static electricity is removed from a predetermined area on the photoreceptor drum, and composite copying and the like are performed.

FIG. 3 is an external perspective view showing the structure of the light emitting means 7 shown in FIG. In the figure, 70 represents an electrochromic display element, which is fixed by an angle 79 to a circuit board 80 made of a metal base material.

FIGS. 4(A) and 4(B) show the front and side cross sections of this light emitting means, respectively. As shown in the figure, the circuit board 80 made of a metal base has a recess formed therein, and the electrochromic display element 70 is connected to the connector 83a.
, 83b, 83c, and 83d. The angle 79 also connects the display element 70 to the circuit board 8.
It is fixed to 0. Display element 70 and circuit board 80
A backlight consisting of four lamps (fuse bulbs) and their reflective cases 81 is housed in the space formed in the recess.

Since the light emitting means is configured as described above, the light of the buffkrite can be selectively guided to the surface of the photoreceptor drum by turning each segment of the electrochromic display element into a colored state or a decolored state.

FIGS. 5 and 6 show an external perspective view and a partial sectional view of the electrochromic display element. As shown in both figures, the electrochromic display element has a glass substrate 1
1.72. One glass substrate 71
As shown in FIG. 6, a plurality of segments 75 made of a transparent conductive film are provided, and the surface thereof is coated with an electrochromic material 74. A counter electrode 76 made of a transparent conductive film is formed on the entire surface of the other glass substrate 72, and an electrolytic solution 73 is formed between the two glass substrates.
is included. The periphery of the two glass substrates pasted together is sealed by a sealing member 78, and a transparent electrode 76 formed on the glass substrate 72 is electrically connected to the inside of this sealing member from the edge of the glass substrate 71. A conductive member 77 is provided at a predetermined location to be taken out.

If tungsten oxide is used as the electrochromic material, the segments can be colored blue by passing a negative charge through a counter electrode, and can be decolored by passing a current in the opposite direction. Further, by using iridium hydroxide as an electrochromic material, gray coloring and decoloring can be performed, and these materials are selected depending on the sensitivity of the photoreceptor drum.

FIG. 7 shows the final stage of the drive circuit for the electrochromic display element. In the figure, if 1 is applied to the input IN, Q2 is turned on and the segment 75 is colored. Further, if +■ is applied to IN, the transistor Q1 is turned on and the segment 75 is decolored.

FIG. 8 shows the relationship of transmittance to wavelength in the colored and decolored states of such an electrochromic display element. As shown in the figure, particularly in the visible region, which is the sensitive region of the photosensitive drum, a high contrast is exhibited between the colored state and the decolored state, and it is possible to sufficiently and selectively remove the charge from the electrostatic latent image.

FIG. 9 is a diagram showing the transmittance characteristics over time for coloring and decoloring of the display element. Now, by applying a colored current from the state where the transmittance is da, that is, the color is erased, the curve b? The transmittance gradually decreases as shown by IA-P-B. Conversely, by applying a decoloring current from a state where the transmittance is colored to dC, the transmittance gradually increases as shown by the curve C-PD. Here, P has transmittance d
The time required for coloring from this intermediate color state to a transmittance of dc is t3-t2, and the time required for decoloring from an intermediate color state to a transmittance of da is also t3-t2. It is.

By starting driving from an intermediate color state in this way, a desired state can be displayed in a relatively short period of time.

FIG. 1 shows a block diagram of a control section of a copying machine using the light emitting means constructed as described above. The entire control is performed by CPU program processing, and the program is written in the ROM in advance. Also, RAM
3 is used as various working areas when executing this program. The display memory 4 is a memory that stores display contents of the electrochromic display element 70,
The contents written in this display memory are read by the display controller 5, and a display control signal is output to the driver 6. The driver 6 includes a drive circuit as shown in FIG. 7 in its output stage, and selectively colors/colors a plurality of segments of the electrochromic display element 70.
Make it colorless. Relay 9 performs on/off control of backlight 82, and CPU
This relay 9 is activated via the 0 port 8.

The operation panel 11 is an input means used for inputting an image area, that is, an area where an electrostatic latent image should be removed in editing modes such as trimming and masking.
I reads this content and writes the display content to the display memory 4. The I10 boat 8 is also connected to various sensors 12 such as a copy lamp, a heater lamp for the fixing roller, motors for driving various rollers, and a sensor for detecting the presence or absence of paper.

The control unit is configured as described above, and the CPU 1 detects a predetermined timing from the start timing of document operation, writes the coloring/decoloring pattern of the electrochromic display element to the display memory 4, and writes the coloring/decoloring pattern of the electrochromic display element to the display controller 5. By outputting a display control signal to the electrochromic display element, the electrochromic display element displays a display. Further, at this time, the relay 9 is activated at a predetermined timing to control the lighting of the backlight 82.

FIG. 10 is a flowchart showing the processing procedure of the CPUI. First, the CPU outputs an instruction signal to the display controller 5 shown in FIG. 1 to drive the display element 70 in a neutral color (nl). As a result, the display controller 5 controls the segments that are already in the colored state to be supplied with a decoloring current for a certain period of time (see Figure 9), and applies the decoloring current to the segments that are already in the decolored state for a similar certain period of time. By applying a colored current, all segments are driven to a neutral colored state.

After outputting the intermediate color drive instruction signal, the CPU reads the keys (n2). If the operated key is a key for setting copy conditions, set the copy conditions (n
3-=n 4-n 5). If no keys are pressed, the area of the document placed on the document table is read.
Display data representing the area to be neutralized is written into the display memory 4 according to the area (n6 to n8). Thereafter, the ready lamp indicating the copy-ready state is turned off, and the display element 7 is sent to the display controller 5 based on the contents of the display memory 4.
An instruction signal for driving 0 is output (n9-n10).

Thereafter, the CPU reads the keys again, and at this time the display controller 5 drives the driver 6 based on the contents written in the display memory 4. When the CPU reads from the display controller 5 that the driver 6 has completed driving the display element 70, it turns on the ready lamp (nll
-=n12).

Note that step 7 is to detect that the document area has changed, such as when the document placed on the document table has moved.
If the document area changes, display data is written again and the same process is performed.

When the colored/decolored state of the display element 70 is determined as described above, the ready lamp is turned off by operating the print key, and the copying process is started (n13
→n 14-=n 15). In the copying process n15, when the static electricity removal timing is detected, turn on the backlight n1
51-=n152), and the backlight is turned off at a timing other than the static electricity removal timing (n153). After the copying process is completed, the ready lamp is turned on and all segments of the display element 70 are driven to the neutral color state again (n16-
■-nl). By driving each segment of the electrochromic display element to an intermediate color state during standby before a copying operation as described above, the display state can be switched immediately after reading the document area. Although an electrochromic display element having rod-shaped segments was used in the embodiment, it may be provided with dot-shaped display electrodes and used in the same manner.

(h) Effects of the Invention As described above, according to the present invention, the light-emitting means for selectively neutralizing the surface of the photoreceptor is composed of a transmission type electrochromic display element in which a plurality of segments or dots are arranged and a backlight. By doing so, it is possible to reduce the cost, and even when using a display element with a slow response speed, it is possible to display the image in a substantially short time.
Copying efficiency can be improved. Furthermore, the segments or dots provided on the display element can be arranged at very fine pitches, making it possible to eliminate static electricity with high resolution.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a control section of a copying machine to which a selective static eliminator according to an embodiment of the present invention is applied, FIG. 2 is a diagram showing the configuration of the copying machine, and FIG. 3 is a light emitting device used in the copying machine. 4(A) and 4(B) are front and side sectional views thereof, FIG. 5 is an external perspective view of an electrochromic display element used in this light emitting means, and FIG. 6 is a perspective view showing the appearance of the means. 7 is a circuit diagram showing the final stage circuit of the driver that drives the electrochromic display element, FIGS. 8 and 9 are diagrams showing the characteristics of the electrochromic display element, and FIG. 10 is a partial cross-sectional view thereof. is the CPU shown in Figure 1
3 is a flowchart showing a processing procedure. 7-Light emitting means, 21-Charging device 22a, 22b-Developing device, 70-Electrochromic display element, 82a to 82
d - lamp, (81,82) - backlight.

Claims (1)

[Claims] (1) A charging device and a developing device are light-emitting means that selectively eliminate static electricity from an electrostatic latent image formed on a photoconductor or selectively eliminate static electricity from a position on a photoconductor where an electrostatic latent image is to be formed. In a copying machine equipped with a static elimination control means provided between the light emitting means and controlling the light emitting means, the light emitting means is composed of a transmission type electrochromic display element having a plurality of segments or dots arranged and a backlight, and the static elimination control means A copying machine with a selective static eliminator, characterized in that the means is provided with means for driving each segment or dot of the electrochromic display element to an intermediate color state during standby before a copying operation.