JPS61110173A - Electrostatic recording device - Google Patents

Abstract

PURPOSE:To stabilize the surface potential of a photosensitive drum by an inexpensive means by starting feeding electricity to a fixing device, and discharg ing the drum electrostatically by a discharging lamp while charging it by a corotron for transfer until the device rises in temperature from room tempera ture to fixation temperature. CONSTITUTION:A copying machine body is powered on, a heater 29 is fed with electricity, and a heat roller 30 is rotated while its temperature is raised. Further, the photosensitive drum 4 begins to be rotated simultaneously with the heat generation of the heater 29, and at the same time the corotron 25 for transfer and discharging lamp 41 are put in operation. Namely, the photosen sitive drum 4 while charged electrostatically by the transfer corotron 25 is discharged by the discharging lamp 41 to make the dark resistance of the photo sensitive body constant and stabilize its surface potential. Then when the heat roller 30 attains to the fixation temperature, the operation of the photosensitive drum 4, transfer corotron 25, and discharging lamp 41 is stopped to hold copying operation in readiness. Consequently, a means which measures the time when the machine is fed as it is without latent image formation is not necessary and the cost is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electrostatic recording device that can stabilize the surface potential of a photoreceptor until the fixing device reaches a fixable temperature after power is turned on. .

Conventional technology If a photoreceptor is left unused for a long time without forming a silent WI image, the dark resistance value increases. It was not possible to obtain recording paper on which records were formed.

Therefore, when recording once after being left unused for a long time, for example, when recording for the first time after turning on the power,
As disclosed in Japanese Patent No. 37500, the photoreceptor was exposed and rotated depending on the time it was allowed to stand without forming a latent image, thereby stabilizing the surface potential.

(c) Problems to be Solved by the Invention As mentioned above, in the conventional technology, in order to stabilize the surface potential, the photoreceptor is rotated and exposed depending on the time it is left without forming a latent image. was. However, this conventional technique requires a means for measuring the time during which a latent image is left standing without forming a latent image, leading to an increase in cost.

B) Means for Solving the Problems The present invention is provided with a means for stabilizing the surface potential of the photoreceptor, and this surface potential stabilizing means is activated when electricity is started to the fixing device and the device is heated from room temperature to normal temperature. This silent recording device is characterized in that it operates until the temperature reaches a temperature that allows fixing.

轡) Function The surface potential stabilizing means of the photosensitive drum is operated in synchronization with the time it takes for the fixing device to reach a fixable temperature from room temperature.

(F) - Dormitory Side FIG. 1 is a schematic sectional view showing an outline of an electronic copying machine as an embodiment of the present invention. First, an overview of the electronic copying machine will be given based on this diagram.

(1) is the copying machine main body, and the top surface 1 of this copying machine main body (1)
A document table (2) made of a transparent glass plate is mounted so as to be slidable in the left and right directions. (3) is the original platen (2)
The cover is attached to the top of the machine so that it can be opened and closed. During copying, the document is held between the document table (2) and the cover (3) and scanned in the left and right direction.
A photoreceptor drum (4) whose peripheral surface is coated with a polyvinyl carbazole photoreceptor is rotatably mounted on the drum. On the top of the photoreceptor drum (4), a short focus lens array (5) is placed on the document table (2) and is used to form an image of the fc original on the circumferential surface of the photoreceptor drum (4).
) are installed vertically. To the right of the short focus lens row (5), an exposure rung (halogen lamp) (6) for illuminating the surface of the document is often seen.

(7) is the summer radiation plate of the exposure rung (6).

A charging corotron (8) for uniformly positively charging (approximately 600 V) the photosensitive drum (4) is fixedly installed upstream of the short focus lens row (5).

A developing device (9) is provided downstream of the short focus lens array (5) for developing the electrostatic latent image formed by the charging corotron (8) and the short focus lens array (5) with toner. ) is provided. This developing device (9) includes a magnetic roller (1r1) for conveying a developer consisting of a mixture of toner and carrier toward the surface of the photoreceptor drum (4).
It also has a rotatably built-in screw for mixing toner and carrier. (2) is a toner hopper detachably attached to the upper part of the developing device (9);
A sponge roller α3 is provided at the bottom of the toner hopper @ to supply the toner stored therein little by little to the developing device (9).

A manual paper feed tray is provided inside the copying machine main body (1), and a start switch (not shown) that also serves as a jam sensor is provided downstream of this paper feed tray. .

α5) is a paper feed cassette detachably attached to the inner bottom of the copying machine main body (1). This paper feed cassette is installed from the right side to the left side of the copying machine main body (1).

The inner bottom of this paper feed cassette αS has copy paper (1
A support plate αη on which the copying machine 61 is placed is swingably provided.
) is provided with an open box that is swingably mounted on the inner bottom of the box and that allows the free end of the push-up lever decoy to be passed through. A torsion spring (not shown) is attached to the push-up lever to rotate it clockwise, and the support plate α'7
1 has its downstream end pushed upward by this torsion spring. Further, above near the downstream end of the paper feed force cellar 1-(151), there is provided a paper feed roller ω that feeds the copy paper u0 one by one. The copy paper 161 is pressed. Therefore, the copy paper 061 is held by the weight of the paper feed roller mother and the torsion spring attached to the push-up lever α&.

- Paper feed cassette) (151) A guide is provided on the downstream side of the paper feed cassette (151) for lifting the copy paper U8 fed by the paper feed roller upward. (
2T) is formed integrally with the paper feed tray Q41 and is configured to be able to rotate about a support shaft inserted through the lower end portion as a fulcrum.

On the downstream side of the guide, the head of the copy paper fed from the paper feed cassette Q51 or the paper feed table is temporarily stopped, and then synchronized with the operation of the document table (2). A register roller pair @ is provided for refeeding.

The developing device (
A transfer corotron y17j3 having the same polarity as the charging corotron (8) is provided for transferring the toner image developed in step 9) onto the copy paper αe. Further, on the downstream side of this transfer corotron (2), copy paper α6. The separating claw pieces are arranged adjacent to each other for peeling off the material. This separation claw ■ is rotatably attached to the spindle of the upper roller ■ of the pair of transport lobes @■.
It is urged to rotate toward the surface of the photoreceptor drum (4) by a spring (not shown).

There is an internal heater on the downstream side of the conveyance roller @ (support).
A fixing device is provided which includes a heat roller (301) into which a halogen lamp of about 800 W is inserted, and a pressure roller 6υ that is pressed against the heat roller. The oil supply pipe ■ to supply silicone oil to this heat roller ■ is lightly pressed. Fine open air bubbles are formed on the wall of this oil supply pipe ■, and the inside is filled with silicone oil. Therefore, the silicone oil in this oil supply pipe (2) penetrates the pipe wall of this vibrator (2) and is gradually supplied onto the heat roller 6D. On the other hand, there is provided a pressurizing panel for pressing this roller (III) counterclockwise, that is, in the direction of the heat roller can.
is a triangular blade for separating the copy paper plate from the heat roller Φ.

Then, the copy paper marked "a" on which the toner image has been fixed by this fixing device is ejected onto the paper ejection tray provided at the top of the paper feed force set (151). In addition,
This paper discharge tray G is configured to be able to move in and out of the copying machine main body (1), and is inserted into the copying machine main body (1) when not needed.

On the downstream side (upward in the figure) of the separation nail base along the rotational direction of the photoreceptor drum (4), toner that has not been completely transferred to the copy paper α mark and remains on the photoreceptor drum (4) is removed. A cleaning device (e) is provided for cleaning. This cleaning device can includes a rubber grade (9) for scraping off residual toner on the photoreceptor drum (4),
There is a built-in screw conveyor for discharging the toner scraped off by this grade σ). The cleaning device aic! A discharge lamp (41i) for removing residual charges on the photoreceptor drum (4) is provided on the downstream side (upper side in FIG. 1) of the EI.

In addition, the right side of the copying machine main body (1), that is, the paper ejection tray 1
A handle (to) for lifting the copying machine main body (1) is fixed on the side surface where the paper feed cassette α5) is attached.

Furthermore, a prismatic rubber cushion is fixed to the side (left side) of the copying machine main body (1) opposite to the side on which the handle @1 is fixed. This rubber cushioning serves to protect the copying machine main body (1) when the copying machine main body (1) is placed on the ground or the like in a lifted position.

After placing the original on the original platen (2), when the copy start switch (not shown) is turned on, the original platen (2) temporarily moves to the left. ,
Thereafter, it moves back to the right, but during this back movement, the original image is projected onto the photoreceptor drum (4), and the photoreceptor drum (
4) An electrostatic latent image corresponding to the original image is formed thereon.

Then, the silent WL latent image is developed with toner in the developing device (9), and this toner image is transferred by the transfer corotronm onto the copy paper stamp fed from the paper feeding cassette (151). In this way, the copy sheet α to which the toner image has been transferred is peeled off from the photosensitive drum (4) by the separating claw (3), and is fixed by heating and pressure in a fixing device.

Then, the fixed copy paper α mark is placed on the paper discharge tray.

In the above-mentioned electronic copying machine, when power is turned on to the copying machine main body, the heater (support) is first energized, and the heat roller (2) starts rotating while the wet ash rises. In addition, the photoreceptor drum (4) starts rotating with the heat generated by the heater, and at the same time the transfer corotron) and the static elimination lamp +
41 works.

Therefore, the photosensitive drum (4) is a transfer corotron B.
Since the photoreceptor is charged by r and removed by the charge removal lamp (41), the dark resistance of the photoreceptor falls to a constant value, and its surface potential is stabilized. In this case, even if only the static elimination run 1 is operated, the surface potential can be stabilized to some extent.

Incidentally, a charging corotron (8) may be operated in place of the transfer corotron (1), and an exposure lamp (6) may be operated in place of the static elimination lamp.

When the temperature of the heat roller continues to rise and reaches the fixing temperature (180°C), the photoreceptor drum (4), the transfer corotron ■, and the like are removed! ? The server stops and enters a standby state for a copy operation.

(G) Effects of the Invention In the present invention, means for stabilizing the surface potential of the photoreceptor is provided, and the surface potential stabilizing means is activated when electricity is started to be applied to the fixing device, and the temperature of the device changes from normal temperature to a temperature capable of fixing. Since the opening operation continues until the end of the opening, there is no need for a means to measure the time that a latent image is left standing without forming a latent image, unlike the conventional technology.

Therefore, an inexpensive and highly reliable electrostatic recording device can be realized.

Note that when a heating roller is used in the fixing device and the temperature of the heating roller is rotated from room temperature to a temperature capable of fixing, the temperature of the heating roller is quickly uniformized.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention. (4)...Photosensitive drum, (5)...
Short focus lens row, (6)... Exposure lamp, (8
)...Corotron for charging, (9)...
Developing device, (1 total... copy paper (recording paper), bad...
...Corotron for transcription, cutting...Static elimination lamp.

Claims (1)

[Claims] 1. A photoreceptor, means for forming an electrostatic latent image on the photoreceptor, means for developing the electrostatic latent image with toner, and transferring the toner image on the photoreceptor to recording paper. and a fixing device for heating and fixing a toner image on a recording paper, the electrostatic recording device is equipped with a means for stabilizing the surface potential of the photoreceptor, and the surface potential stabilizing means is . An electrostatic recording device, wherein the electrostatic recording device operates during the period from when power is started to the fixing device until the device reaches a fixable temperature from room temperature. 2. The static electricity removal lamp according to claim 1, wherein a static elimination lamp is provided in a portion facing the photoconductor, and the static elimination lamp is turned on and the photoconductor moves while the fixing device reaches a fixable temperature from room temperature. Electric recording device. 3. The electrostatic recording device according to claim 2, wherein a transfer corotron as a transfer means operates in synchronization with lighting of the static elimination lamp. 4. The fixing device includes at least one pair of heating rollers, and the heating roller continuously rotates from room temperature to a fixing temperature. electrostatic recording device.