JPH0553378A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To simplify an operation procedure for exchanging an image carrier unit at the time of maintenance. CONSTITUTION:In the electrophotographic device forming an image on the image carrier unit K, transferring that image on a sheet 20, and ejecting the sheet 20 after fixing at a fixing device 26, the fixing device 26 is provided freely movable between a first position fixing the transfer image and a second position where the image carrier unit K can be extracted. Furthermore, when an top cover 10a of the device main body 10 is opened, an energizing member 31 is provided to move the fixing device interlocked with that, from the first position to the second position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic method (transferring an image formed on a photoconductor to a sheet such as paper, OHP paper, envelopes, etc.) using a laser, such as a printer, a copying machine and a facsimile. The present invention relates to an electrophotographic apparatus that records on a sheet according to a method of performing).

[0002]

2. Description of the Related Art Conventionally, in a laser printer, as shown in FIG. 5, for example, the surface of an image bearing member (photoreceptor) 1 is charged, and then laser light is irradiated from an optical writer to electrostatically charge the surface. A latent image is formed, the latent image is developed by the developing device 2 to become a visible image, the visible image is transferred to a sheet by a transfer device, and then the image is thermally fixed by a fixing device 6 for recording. is there. By the way, since the image carrier 1 and the developing device 2 are consumable parts, they are unitized as an image carrier unit K and a developing unit G as shown in the figure, and can be individually replaced. However, there is a case where the replacement order is determined due to functional or configuration restrictions on the replacement. In such a case, for example, when replacing the image carrier unit K as shown in FIG. 6, first, the upper cover 4 of the apparatus main body 3 is rotated counterclockwise about the fulcrum 4a to open it, and then the side is opened. The cover 5 is rotated clockwise about the fulcrum 5a to open it. Then, the developing unit G is slightly pulled out of the apparatus main body 3 and separated from the image carrier unit K.
After that, the image carrier unit K was taken out from the apparatus main body 3 in the direction of the arrow and replaced.

[0003]

However, in the conventional electrophotographic apparatus, since many operation procedures are required to replace the image carrier unit during maintenance, there is a problem in that the replacement work is time-consuming and troublesome.

Therefore, an object of the present invention is to simplify the operation procedure for replacing the image carrier unit during maintenance.

[0005]

Therefore, the invention described in claim 1 is, for example, as shown in the following illustrated embodiments,
In an electrophotographic apparatus in which an image is formed on the image carrier unit K, the image is transferred to the sheet 20, the image is fixed by the fixing device 26, and the sheet 20 is discharged, the fixing device 26 is used to fix the transferred image. When the upper cover 10a of the main assembly 10 of the apparatus is opened, the fixing device 2 can be moved freely between the first position and the second position where the image carrier unit K can be taken out.
Biasing member 3 for moving 6 from the first position to the second position
1 is provided.

According to a second aspect of the present invention, for example, as shown in the following illustrated embodiment, an image is formed on the image carrier unit K, the image is transferred to the sheet 20, and is fixed by the fixing device 26, and In the electrophotographic apparatus for discharging the sheet 20, the fixing device 26 is movable between a first position for fixing the transferred image and a second position for allowing the image carrier unit K to be taken out, and the fixing device 26 is provided. Is provided with a biasing member 31 for biasing the first position from the first position to the second position, and a regulating member 40 for regulating the movement of the fixing device 26 by the biasing member 31 is provided.

According to a third aspect of the present invention, in the electrophotographic apparatus according to the first or second aspect, for example, guide rollers 30 are rotated on both sides of the fixing device 26 as shown in the following illustrated embodiment. Freely installed, the guide roller 30
Are formed on both side plates of the apparatus main body 10 so that the fixing device 26 can be moved between the first position and the second position.

According to a fourth aspect of the present invention, in the electrophotographic apparatus according to the second aspect, for example, as shown in the following illustrated embodiments, the restricting member 40 is provided with a hooking portion 40a, and the apparatus body 10 is provided. While rotatably supporting it, the restriction member 40 is given a habit of rotating in the hanging direction, while
When the fixing device 26 moves from the second position to the first position, the regulating member 40 is temporarily retracted against the tendency of rotation, and when the fixing device 26 reaches the first position, the hooking portion is provided. Four
It is characterized in that a hooking protrusion 42 for hooking 0a is provided.

[0009]

When the image carrier unit K is replaced, the upper cover 10a of the apparatus body 10 is opened and the fixing device 26 is moved from the first position to the second position. The carrier unit K can be taken out.

According to the second aspect of the invention, when the image carrier unit K is replaced, the regulation of the regulation member 40 is released, and the fixing member 26 moves the fixing device 26 from the first position to the second position. The image carrier unit K can be taken out.

According to the third aspect of the invention, when the fixing device 26 is moved from the first position to the second position, the fixing device 2 is moved.
The movement of 6 is guided by the guide groove 32.

According to the fourth aspect of the invention, when the fixing device 26 is moved from the second position to the first position, the regulating member 40 is used.
Once retracted to the first position again, the hooking portion 40a is hooked on the hooking protrusion 42 to restrict the movement of the fixing device 26.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an overall schematic structure of an internal mechanism in a laser printer according to an embodiment of the present invention. Reference numeral 10 in the figure denotes the apparatus main body. The apparatus main body 10 is provided with an upper cover 10a and can be opened and closed about a fulcrum P. A belt-shaped image carrier (photoreceptor) 11 is provided substantially in the center of the apparatus main body 10. Around the image carrier 11, a charging device 12, a developing device 13, a transfer device 14, and a cleaning device 15 are arranged in this order in the driving direction indicated by the arrow in the figure.
The image carrier 11, the transfer device 14, and the cleaning device 15
And are unitized as an image carrier unit K. On the other hand, the charger 12 and the developing device 13 are unitized as a developing unit G. The image carrier unit K
Also, the developing unit G can be individually replaced. A laser writer 16 is provided below the developing unit G, and a paper feed cassette 21 for accommodating sheets (paper) 20 is detachably provided below the laser writer 16.

A sheet feeding roller 22 is provided on the sheet feeding side of the sheet feeding cassette 21. A start end of a sheet conveying path 23 for conveying the sheet 20 to be sent out is provided near the sheet feeding roller 22. The sheet conveying path 23 passes through the inside of the front side on the right side of the apparatus main body 10 in the drawing, and
To the rear side on the left side in the drawing, and communicates with the paper discharge port 24. A registration roller pair 25 is arranged in front of the transfer device 14 in the middle of the sheet conveying path 23,
After the transfer device 14, a fixing device 26 is arranged near the image carrier unit K. A transport roller 27 is provided in the fixing device 26.

When forming an image by the electrophotographic method using the laser printer, the sheet feeding roller 22 is driven to feed the sheet 20 in the sheet feeding cassette 21 in the arrow direction. Then, the sheet 20 is abutted against the registration roller pair 25 through the sheet conveying path 23, and is conveyed to the upper side of the image carrier 11 with timing there. The image carrier 11 is driven in the counterclockwise direction as shown by the arrow, and at that time, the surface is uniformly charged by the charger 12, and the laser light from the laser writer 16 is irradiated to the image carrier 11. An electrostatic latent image is formed on. This latent image is visualized by toner as it passes through the developing device 13. Then, this visible image is transferred to the lower surface of the sheet 20 conveyed to the upper side of the image carrier 11 by the transfer device 14, and after the transfer, the sheet 20 is conveyed to the fixing device 26 to apply heat and pressure. Establish. The recorded sheet 20 exiting the fixing device 26 is conveyed by the conveying rollers 27, ejected from the ejection port 24, and stacked. On the other hand, the image carrier 11 after the transfer of the visible image is cleaned by the cleaning device 15.

By the way, the fixing device 26 is provided movably between a first position for fixing the transferred image on the apparatus main body 10 and a second position for allowing the image carrier unit K to be taken out. The fixing device 26 is provided with a pair of upper and lower guide rollers 30 rotatably on both front and rear sides in the drawing. On the other hand, the apparatus main body 10 includes the guide roller.
A guide groove 32 with which the guide roller 30 engages is provided in a vertically long shape on both side plates facing each other. And the fixing device 2
One end of the biasing member 31 is pressed against the lower surface of 6. The urging member 31 presses the other end to an appropriate position of the apparatus main body 10 to urge the fixing device to the second position. A pushing projection 33 is provided on the upper cover 10a of the apparatus main body 10 so as to project downward. The pushing projection 33 has its lower end abutted against the upper surface of the fixing device 26 and holds the fixing device 26 at the first position against the biasing member 31.

However, during maintenance, when the upper cover 10a is rotated counterclockwise about the fulcrum P, the biasing member 31 pushes up the fixing device 26 in accordance with the rotation. At that time, the guide roller 30 rolls along the guide groove 32 to guide the movement of the fixing device 26. When the upper cover 10a is wide open as shown in FIG. 2, the fixing device 26 moves to the second position. Therefore,
The image carrier unit K is taken out and replaced. After the replacement, when the upper cover 10a is closed again, the fixing device 2
The pushing projection 33 abuts on the upper surface of 6, and the fixing device 26 is pushed down against the biasing force of the biasing member 31.
Then, the guide roller 30 rolls along the guide groove 32, and the fixing device 26 moves from the second position to the first position. Then, as shown in FIG. 1, when the upper cover 10a is completely closed, the fixing device 26 is at the first position.

By the way, in the illustrated embodiment described above, the movement of the fixing device 26 from the first position to the second position is performed by the upper cover 10.
It is configured to be restricted by the pushing protrusion 33 of a. However, the movement of the fixing device 26 from the first position to the second position may be restricted by the restriction member 40 as shown in FIG. That is, the regulating member 40 is lever-shaped, and has a hook 40a at one end.
Equipped with. The fixing device 26 is provided in the vicinity of both sides of the fixing device 26 so that the fixing device 26 can rotate about the shaft 41.
The latching portions 40a are hooked on the latching protrusions 42 protruding on both sides of the latching portion 40a. At the other end of the regulating member 40, the tension spring 4
Hang one end of 3. The tension spring 43 has the other end hooked at an appropriate position of the apparatus main body 10 to give the regulating member 40 a turning habit in the hooking direction.

However, when the fixing device 26 is at the first position as shown in the drawing, the hooking portion 40a of the regulating member 40 is provided.
Is locked to the hooking protrusion 42 to restrict the movement of the fixing device 26 to the second position. Then, for example, when a jam occurs, the upper cover 10a is opened and the fixing process is performed with the fixing device 26 fixed at the first position. Since the fixing device 26 does not move to the second position even when the upper cover 10a is opened, it does not interfere with the jam processing. On the other hand, at the time of maintenance, as shown in FIG. 4, the upper cover 10a is opened widely, and the latching of the latching portion 40a is released by an appropriate operation. Then, the biasing member 43 works to push up the fixing device 26 and move it to the second position. At that time, the guide groove 3
The guide roller 30 rolls along the line 2 and guides the movement of the fixing device 26. Then, the fixing device 26 is set to the second position,
The image carrier unit K is taken out and replaced. After the replacement, when the upper cover 10a is closed again, the fixing device 2
The pushing projection 33 abuts on the upper surface of 6, and the fixing device 26 is pushed down against the biasing force of the biasing member 31.
Then, the fixing device 26 moves from the second position to the first position. At that time, the latching projection 42 abuts on the latching portion 40a of the regulating member 40, and the regulating member 40 is temporarily retracted against its rotational habit. When the fixing device 26 is again in the first position as shown in FIG.
0 rotates in the hooking direction due to the turning habit and its hooking portion 4
0a is hooked on the hooking protrusion 42.

[0021]

Therefore, according to the first aspect of the present invention, when the upper cover of the main body of the apparatus is opened during the replacement of the image carrier unit, the fixing device is moved from the first position to the second position in conjunction with this.
Since it can be moved to the position and the image carrier unit can be taken out, the operation procedure can be simplified, and the replacement work of the image carrier unit can be easily performed.

According to the second aspect of the present invention, when the regulation of the regulation member is released when the image carrier unit is replaced, the fixing device is moved from the first position to the second position by the urging member. Since it is possible to take out the carrier unit, the operation procedure can be simplified and the image carrier unit can be replaced easily and easily. Further, since the fixing device is regulated by the regulation member to bring the fixing device to the first position, it is possible to prevent the fixing device from interlocking even when the upper cover is opened during jam processing, which prevents the jam processing from being an obstacle.

According to the third aspect of the invention, when the fixing device is moved to the first position and the second position, the movement is guided by the guide groove, so that the fixing device can be moved reliably and smoothly. be able to.

According to the fourth aspect of the invention, when the fixing device is moved from the second position to the first position, the restricting member is temporarily retracted, and the fixing device is brought to the first position again. Since the hooking portion is hooked on, the movement of the fixing device can be automatically controlled, the operation procedure can be simplified, and the replacement work of the image carrier unit can be easily and easily performed.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an entire internal mechanism in a laser printer that is an embodiment of the present invention.

FIG. 2 is a state view in which an upper cover is opened.

FIG. 3 is a schematic configuration diagram of an entire internal mechanism in a laser printer which is another embodiment of the present invention.

FIG. 4 is a state diagram in which the upper cover is opened and the regulation of the regulation member is released.

FIG. 5 is a schematic configuration diagram of an entire internal mechanism in a conventional laser printer.

FIG. 6 is an explanatory diagram when the image carrier unit is replaced during maintenance.

[Explanation of symbols]

 10 Device Main Body 10a Upper Cover 20 Sheet 26 Fixing Device 30 Guide Roller 31 Biasing Member 32 Guide Groove 40 Controlling Member 40a Locking Part 42 Locking Protrusion K Image Carrier Unit

Claims (4)

[Claims] 1. An electrophotographic apparatus in which an image is formed on an image carrier unit, the image is transferred to a sheet, the image is fixed by a fixing device and the sheet is discharged, and the fixing device fixes the transferred image. When the upper cover of the main body of the apparatus is opened, the fixing device is moved from the first position to the second position. An electrophotographic apparatus provided with a biasing member. 2. An electrophotographic apparatus in which an image is formed on an image carrier unit, the image is transferred to a sheet, the image is fixed by a fixing device and the sheet is discharged, and the fixing device fixes the transferred image. A biasing member is provided which is movable between a first position and a second position allowing the image carrier unit to be taken out, and biases the fixing device from the first position to the second position. An electrophotographic apparatus comprising a regulating member for regulating the movement of the fixing device by a member. 3. A guide roller is rotatably provided on both sides of the fixing device, and guide grooves engaged with the guide roller are formed on both side plates of the apparatus main body, respectively, and the fixing device is arranged at the first position. And can be moved to the second position,
The electrophotographic apparatus according to claim 1. 4. The restraint member is provided with a latching portion to rotatably support the apparatus main body, and the restraint member is provided with a turning habit in the latching direction. On the other hand, the fixing device is provided with: When it moves from the second position to the first position, the restricting member is temporarily retracted against the habit of turning, and when it reaches the first position, the locking portion is locked. The electrophotographic apparatus according to claim 2, wherein a projection is provided.