JPH0460677A - electrophotographic equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention is applicable to printers, copiers, facsimile machines, etc. that use lasers, etc., which use electrophotography (recording is performed by transferring an image formed on a photoreceptor to a recording medium such as paper). The present invention relates to an electrophotographic apparatus that performs recording on a recording medium using a recording method.

Conventionally, in this type of electrophotographic apparatus, as shown in FIG. 4, for example, after being transferred to a recording medium, the transferred image is fixed by a fixing means 1, and the recording medium is transferred to a paper ejecting means. While ejecting in 2,
For example, when a paper jam occurs, the lower body 3 of the device body 3
The jammed paper is removed by opening the upper main body 3b relative to a.

By the way, in order to suppress the temperature rise inside the main body 3 of the apparatus due to the fixing means 1, the fixing means 1 and the paper ejecting means 2 are communicated with each other to allow outside air to flow from the ventilation hole 4 on the paper ejecting means 2 side to the fixing means 1 side. At the same time, the fixing means 1 and the exhaust means 5 are communicated with each other, and the exhaust means 5 forcibly exhausts the hot air around the fixing means 1 to the outside of the main body 3 of the apparatus.

However, in the conventional electrophotographic apparatus of this type, even if the air is forcibly exhausted by the exhaust means 5, the outside air taken in through the ventilation hole 4 is exhausted as it is, and the hot air around the fixing means 1 is sufficiently removed. There was a problem with poor exhaust efficiency. In addition, when handling a jam, the area around the fixing means becomes hot and difficult to work with, and the worker's hands are likely to touch the fixing means 1, which may cause burns, resulting in poor workability and poor safety. Ta.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to improve exhaust efficiency to prevent internal temperature from rising, and to improve workability and safety during maintenance.

Means for Solving the Problems In order to achieve the above object, the present invention provides that, after being transferred to a recording medium, the transferred image is fixed by a fixing means and the recording medium is ejected by a paper ejecting means. In an electrophotographic apparatus whose upper body is opened relative to the main body, during recording, the fixing means and an exhaust means for exhausting hot air around the fixing means are communicated, and the exhaust means and the paper ejecting means are connected. A shielding plate is provided at a blocking position, and rotation transmission means is provided for rotating the shielding plate to a position covering the fixing means when the upper main body is opened during the maintenance. .

Further, in the present invention, it is preferable that electrostatic flocking is provided on the surface of the shielding plate that covers the fixing means.

Further, in the present invention, it is preferable that the surface of the shielding plate covering the fixing means is provided with irregularities.

During recording, the shielding plate communicates between the fixing means and the exhaust means and blocks the exhaust means from the paper ejection means, and the exhaust means exhausts hot air around the fixing means.

When the upper body is opened during maintenance, the shielding plate is rotated by the rotation transmission means to cover the fixing means.

In addition, the operator's hands do not come into contact with the flocking or unevenness on the surface of the shielding plate, and do not touch the entire surface of the shielding plate.

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a schematic overall structure of the internal mechanism of a laser printer according to an embodiment of the present invention. In FIG. 6, reference numeral 8 indicates the main body of the apparatus. Inside the main body 8 of the apparatus, a belt-shaped photoreceptor 9 is provided at the center.

Around the photoreceptor 9, a charging means 10, an optical writing means 11, a developing means 12, a transfer means 13, and a cleaning means 14 are arranged in order in the rotational direction (clockwise in the figure). The photoreceptor 9 and the cleaning means 14 are housed in a casing 15 to constitute an image forming kit 16. The casing 15 of the image forming kit 16 includes an optical writing window (not shown) for irradiating the photoreceptor 9 with laser light, a developing roller window for pressing the photoreceptor 9 through the developing roller of the developing means 12, and the like. . A paper feed tray 1 is provided below the image forming kit 16, transfer means 13, etc.
7 is removably loaded, and paper 18 which is a recording medium is stored inside.
to store. A paper feeding section 21 having a paper feeding roller 19, a paper guide plate 20, etc. is provided on the paper feeding side of the paper feeding tray 17. On the other hand, on the opposite side of the paper feed unit 21 across the transfer unit 13, a conveyance guide 22, a fixing unit 23, a paper discharge unit 24, etc. are arranged in this order. Above the fixing means 23, an exhaust means 25 including an exhaust fan 25a is arranged. Also.

At the upper side of the apparatus main body 10 in the figure, there is provided a paper ejection receiver 26 for receiving the paper 18 to be ejected.

When recording by electrophotographic process using the laser printer, the paper feed roller 19 is driven to feed the paper 18 from the paper feed tray 17. and,
The paper 18 is guided and conveyed by the paper guide plate 20, and then the leading edge of the paper 18 is detected by a registration sensor (not shown). However,
A pair of registration rollers 29 and 2
Hit 9 and stop.

On the other hand, the photoreceptor 9 is rotated clockwise in FIG. 1, and its surface is sequentially charged in a negative manner by a charging means 10, and then a laser beam is irradiated by an optical writing means 11 to form an electrostatic latent image on the surface. The electrostatic latent image is sequentially visualized by toner when it passes through the developing means 12. Then, in synchronization with the image, the paper 18 that had been in contact with the registration roller 29 described above is sent out toward the photoreceptor 9. However,
The image on the photoreceptor 9 is transferred to the paper 18 by the transfer means 13.
Transfer to. After the image transfer, residual toner remaining on the photoreceptor 9 is scraped off by a cleaning means 14, and the surface of the photoreceptor 9 is cleaned by the cleaning means 14.

On the other hand, the paper 18 is transferred to the fixing means 2 by the conveyance guide 22.
3, and the transferred image is fixed by the fixing means 23 by applying heat and pressure. After fixing, the sheets 18 are discharged from the apparatus main body 8 and stacked one after another on the sheet discharge tray 26. During the above-described recording, the hot air generated around the fixing means 23 is discharged by the exhaust means 25 to the outside of the apparatus main body 8 through an exhaust path (not shown). Further, the hot air inside the paper ejection means 24 due to the paper 18 after fixing is removed through the ventilation hole 30.
through the air to the outside of the device main body 8.

By the way, the device main body 8 of the laser printer described above is divided into an upper main body 8a and a lower main body 8b.
is pivotably attached to the lower body 8b about a pin 32 as a fulcrum. That is, as shown in FIG. 2, a pair of brackets 33 are provided on the upper body 8a, and the lower ends of the brackets 33 are attached to the pins 32. A first gear 35 of a rotation transmission means 34 is coaxially fixed to the pin 33 . The rotation transmission means 34 includes the first gear 35, a second gear 36 that meshes with the first gear 35, a first sprocket 37 that is coaxial and integral with the second gear 36, and a second sprocket 38. , and a chain 39 stretched between both sprockets 37 and 38.

The second sprocket 38 is fixed to a one-rotation central shaft 38a. The rotation center axis 38a protrudes outward from both ends of the base end portion of the shielding plate 40. The shielding plate 40 is made of a heat-resistant plastic plate, has a bent portion 40a at its tip, and has electrostatic flocking applied to the surface opposite to the bending direction. The shielding plate 40 is disposed at a position that communicates between the fixing means 23 and the exhaust means 25 and blocks the exhaust means 25 and the paper ejection means 24, and is arranged at a position that connects the fixing means 23 and the exhaust means 25 and blocks the exhaust means 25 and the sheet discharge means 24. Both ends are attached to the exterior 41 of the fixing means 23.
Alternatively, it is rotatably attached to an appropriate location within the lower body 8b. a wall 42 that hangs the shielding plate 40 into the upper body 8a at a position that blocks the space between the exhaust means 25 and the paper discharge means 24;
through the sealing material 43.

Since the shielding plate 40 blocks the exhaust means 25 and the sheet discharge means 24, the exhaust means 25 can efficiently exhaust the hot air around the fixing means 23 to the outside of the apparatus main body 8. 23 can be prevented from increasing the temperature inside the device main body 8. On the other hand, during maintenance, when the upper body 8a is opened as shown in FIG. 3, the first gear 35
is rotated counterclockwise, the second gear 36 and first sprocket 37 are rotated clockwise to drive the chain 39, and the second sprocket 38 is rotated clockwise to drive the shielding plate 4.
0 to cover the exterior 41 of the fixing means 23. Therefore, for example, when a paper jam occurs in the paper ejection means 24,
Jam removal can be carried out without directly touching the fixing means 23 with the hand6. Furthermore, even if the hand touches the shielding plate 40, it only touches the flocked hair, so the heat can be reduced.

Then, when the upper main body 8a is closed after the maintenance, each component of the rotation transmission means 34 that is linked thereto is rotated in the opposite direction as described above, and the shielding plate 40 is separated from the fixing means 23 and the first Return to the shutoff position shown in the figure.

In the above explanation, the rotation transmission means 34 is connected to the first and second gears 35, 36, . Although the first and second sprockets 37 and 38 and the chain 39 are used in the present invention, the rotation transmission means 34 may be constructed using a cam system or a link mechanism. Moreover, although the configuration is such that the surface of the shielding plate 40 is electrostatically flocked, the present invention may also be configured such that the surface of the shielding plate 40 is textured.

From the above, according to the electrophotographic apparatus according to the invention set forth in claim 1, the shielding plate blocks the paper ejection means and the exhaust means, so that the paper ejection means is ventilated. The outside air sucked in through the hole does not need to be discharged.

The hot air around the fixing means can be efficiently exhausted by the exhaust means,
Temperature rise inside the device body can be accurately prevented.

In addition, when the upper body is opened during maintenance, the shielding plate is rotated to cover the fixing means by the rotation transmission means linked to it, so there is no risk of touching the fixing means directly with the hands, and for example, when removing jammed paper, the shield plate is rotated to cover the fixing means. It can be done safely.

Furthermore, according to the electrophotographic apparatus according to the invention described in claim 2.3, since the surface of the shielding plate is provided with flocking or unevenness, it is possible to reduce the heat when touched with the hand, thereby making maintenance work easier. Safety can be further improved.

[Brief explanation of the drawing]

Fig. 1 is a schematic diagram of the entire internal mechanism of a laser printer according to an embodiment of the present invention, Fig. 2 is a schematic diagram of a part of the internal mechanism, and Fig. 3 is an explanation when the upper body of the laser printer is opened. FIG. 4 is a schematic diagram of a part of a conventional laser printer. 8......Device body 8a...Upper body 8b...Lower body 23...Fixing Means 24... Paper discharge means 25... Exhaust means 34... Rotation transmission means 40... Shielding board

Claims (1)

[Claims] 1. After being transferred to a recording medium, the transferred image is fixed by a fixing means, and the recording medium is ejected by a paper ejecting means, while the upper body is opened relative to the lower body during maintenance. At the time of recording, a shielding plate is provided at a position that communicates between the fixing means and an exhaust means for exhausting hot air around the fixing means and isolates between the exhaust means and the paper ejecting means; 1. An electrophotographic apparatus, further comprising a rotation transmission means that rotates the shielding plate to a position covering the fixing means when the upper main body is opened during maintenance. 2. The electrophotographic apparatus according to claim 1, further comprising electrostatic flocking on the surface of the shielding plate that covers the fixing means. 3. The electrophotographic apparatus according to claim 1, wherein the shielding plate covering the fixing means has an uneven surface.