JPH09146396A - Electrophotographic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily perform the attaching/detaching operation of a fixing unit to/from a drawer member without using a tool. SOLUTION: In an insertion process where the drawer member 33 on which the fixing unit 7 is placed is inserted into the inner part of a device main body, the unit 7 is pressed by a pressing part 41 to abut on a receiving part 31, whereby its position in an inserting direction is decided. Then, the unit 7 is locked by a locking body 40 so as to prevent the unit 7 from floating from the placing surface 34 of the member 33. In a pulling-out process where the member 33 is pulled out from the device main body, the unit 7 is pressed by a drawer part 38a to be pulled out in the drawing direction so as to release the locking state by the locking body 40. Thus, the attaching/detaching operation of the unit 7 to/from the member 33 is easily performed without using the tool, and setting parts such as a screw, etc., are prevented from being lost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus that transfers an image formed on the surface of a photoconductor by an electrophotographic method onto a transfer paper and then fixes the transferred image.

[0002]

2. Description of the Related Art Conventionally, as an electrophotographic device such as a laser printer or a copying machine, there is a device in which a drawing-out member for holding the fixing unit is provided so as to be freely drawn out for maintenance of the fixing unit.

[0003]

Conventionally, since the fixing unit is attached to the pullout member by a fastening member such as a screw, when the parts of the fixing unit are replaced, the fixing unit is attached to the pullout member. A tool is required to attach and detach, and the work is troublesome. In addition, the fastening parts such as screws may be lost.

[0004]

SUMMARY OF THE INVENTION According to the present invention, a drawing member having a mounting surface on which a fixing unit for fixing a transfer image on a transfer paper is mounted is provided in an apparatus body of an electrophotographic apparatus so as to be freely drawn out. A pressing portion that presses the fixing unit in the insertion process of inserting the pullout member into the apparatus main body, and a locking body that engages with the fixing unit and prevents the fixing unit from floating from the mounting surface. The pullout member is provided with a pullout portion that presses the fixing unit in the pullout direction in the pullout process of pulling out the pullout member from the apparatus body, and the pullout member is inserted into the apparatus body in the latter half of the insertion process. A receiving portion that supports the fixing unit is provided in the main body of the apparatus. Therefore, when the pull-out member on which the fixing unit is placed is inserted into the back of the main body of the apparatus, the fixing unit determines the position in the insertion direction when the fixing unit is pressed by the pressing portion and comes into contact with the receiving portion, and is locked by the locking body. Therefore, the pulling-out member is prevented from floating from the mounting surface. When the pull-out member is pulled out from the apparatus main body, the fixing unit is pushed by the pull-out portion and pulled out in the pull-out direction and the locked state with the locking body is released, so that the fixing unit can be removed from the pull-out member. .

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. 1 is an exploded perspective view showing the relationship between the fixing unit, the drawing member, and the receiving portion, and FIG. 2A is a vertical sectional front view showing the relationship between the fixing unit, the drawing member, and the receiving portion.
2B is a plan view of a part of FIG. 2A, FIG. 3A is a vertical cross-sectional front view showing a state where the fixing unit is completely attached, and FIG.
3 is a plan view of a part of FIG. 3A, and FIG. 4 is a vertical sectional front view showing the internal structure of the electrophotographic apparatus.

First, the internal structure of the electrophotographic apparatus will be described with reference to FIG. In the figure, A is an electrophotographic apparatus. A plurality of paper feed cassettes 2 are provided below the main body 1 of the electrophotographic apparatus A.
A sheet feeding roller 3 for pulling out the transfer sheet is rotatably provided at the end of the sheet. In the paper feed path 5 for guiding the transfer paper drawn out by the paper feed roller 3 to the registration roller 4, a transport roller 6 is provided.
Is provided. A conveyor belt 8 for conveying the transfer paper supplied by the registration rollers 4 to the fixing unit 7 is obtained by winding an endless belt 11 around a driving roller 9 and a driven roller 10 driven by a motor (not shown). This is a structure in which a rotatable tension roller 12 is pressed against the inner surface of 11. Further, a paper discharge tray 13 is formed on the top of the apparatus main body 1, and a paper discharge tray 14 is provided on the side. The exit of the fixing unit 7 and the paper discharge tray 13 are connected by a paper discharge path 15. And the fixing unit 7
A rotatable switching claw 16 is provided near the exit of the fixing unit 7 for performing a switching operation of guiding the transfer paper having passed through the paper ejection path 15 to the paper ejection receiver 13 or the paper ejection tray 14. ing.

Further, on the upper part of the conveyor belt 8, yellow, yellow from the upstream side to the downstream side in the conveying direction of the transfer paper,
Developing units 17Y, 17M, 17C and 17BK for forming magenta, cyan and black images are sequentially arranged. These developing units 17Y, 17M, 17
C and 17BK are a photoconductor 19 rotatably provided on both side plates 18 of the apparatus main body 1, a charger 20 for uniformly charging the surface of the photoconductor 19, and a developing device for developing an electrostatic latent image on the photoconductor 19. Cleaner 2 for cleaning the surfaces of the container 21 and the photoconductor 19
2. Static elimination lamp 2 for eliminating charges on the surface of the photoconductor 19
It has 3 etc. Further, below the photoconductor 19, a transfer roller 24 that comes into contact with the inner surface of the conveyor belt 8 is rotatably provided. Further, the side plate 18 of the apparatus body 1 is provided with deflection scanning type exposure devices 25Y, 25M, 25 corresponding to the developing units 17Y, 17M, 17C, 17BK.
C and 25BK are arranged.

In such an electrophotographic apparatus, when a signal for forming an image is input from a host computer (not shown) or the like, the transfer paper in the paper feed cassette 2 is fed by the paper feed roller 3 and the carrying roller 6. Register roller 4 fed by
Stand by while contacting the nip part of. On the other hand, images are sequentially formed from the photoconductor 19 on the right side. That is, in the yellow developing unit 17Y, the charger 20 charges the surface of the photoconductor 19 in the process of rotating the photoconductor 19,
The exposing unit 25Y scans the charged portion with the light beam to form an electrostatic latent image, and the developing unit 21 develops the electrostatic latent image.
Similarly, a magenta developing unit 17M, a cyan developing unit 17C, and a black developing unit 17BK.
An image is selectively formed on the photoconductor 19 of. And
Since the registration rollers 4 rotate in synchronization with these image forming timings, the image on the photoconductor 19 is transferred to the transfer roller 24 while the transfer paper is being transferred by the transfer belt 8.
Is transcribed. The transfer paper that has reached the end of the transfer belt 8 is folded on the driving roller 9 having a small curvature and the belt 11
The transfer image goes straight to the fixing unit 7, and the transfer image is fixed by the fixing unit 7. The transfer paper after fixing is discharged to the discharge receiver 13 or the discharge tray 14.

Next, the support structure of the fixing unit 7 will be described. As shown in FIGS. 2 and 3, the fixing unit 7 elastically contacts the pair of rotatable fixing rollers 26, 27 and the upper fixing roller 26 to wind the transfer paper around the fixing roller 26. The cover case 29 is provided with rotatable peeling claws 28 and the like for preventing the same. In this case, the upper fixing roller 26 is a heating roller having a heater 26a therein, and the lower fixing roller 27 is a pressure roller pressed against the upper fixing roller 26. On both sides of the cover case 29 corresponding to the width direction of the transfer sheet, V-shaped contact portions 30 such as a trough of the rack are formed on the same straight line parallel to the axis of the fixing rollers 26 and 27. Has been done.
Here, the left and right abutting portions 30 are arranged on the same straight line means that any portion of the left and right abutting portions 30 is parallel to the axis of the fixing rollers 26 and 27 as long as they are symmetrical to each other. It means that they should be arranged on the same straight line. And the receiving part 31 which receives these contact parts 30
Support shafts 32 provided on both sides are provided on the same straight line parallel to the axis of the photoconductor 19. The left and right receiving portions 31 are not limited to the round bar shape, and other shapes are conceivable, so that any portions may be arranged on the same straight line as long as they are symmetrical positions. In this example, the support shaft 32 is formed into a round bar shape in which the receiving portions 31 on both sides and the intermediate portion have the same cross section, and the side plate 18 that pivotally supports the photoconductor 19 is provided.
The parallelism between the left and right receiving portions 31 and the shaft center of the photoconductor 19 can be accurately and easily determined.

Here, a supplementary description will be given of modified examples of the contact portion and the receiving portion. The left and right receiving portions 31 on the side of the apparatus main body 1 are formed by using both ends of the support shaft 32, but a short shaft may be coaxially arranged and the outer circumference of the short shaft may be used as the receiving portion. Also,
The contact portion on the fixing unit 7 side and the receiving portion on the apparatus main body 1 side are
The contact surface is not limited to the round bar-shaped receiving portion 31 or the V-shaped contact portion 30, but a shaft including the round bar is used as the receiving portion or the contact portion, and the contact surface includes the recessed portion that contacts the shaft-shaped object. May be used as the contact portion or the receiving portion.

Further, as shown in FIGS. 1 to 3, a drawing member 33 for holding the cover case 29 of the fixing unit 7 is provided. The pull-out member 33 has a mounting surface 34 on which the cover case 29 is mounted, and side surfaces 35 bent from both sides of the mounting surface 34, and one side surface 35 includes the device body 1 (FIG. 4). The lock portion 36 is formed so as to be locked by a lock mechanism (not shown) provided in (see). A horizontally elongated opening 38 is formed on the mounting surface 34 for inserting a bent piece 37 bent downward from the end of the cover case 29. Further, the opening 38 is erected horizontally from the inside of the opening 38. A reference shaft 39 is provided as a pair of left and right locking bodies, and a stud 40 with a collar is provided as a pair of left and right locking bodies that are erected upright. A coil spring 41, which is a pressing portion for pressing the bending piece 37 of the fixing unit 7 against the receiving portion 31, is fitted on the outer periphery of the reference shaft 39. These coil springs 41 have a free length that is longer than the entire length of the reference shaft 39, and are separated from the reference shaft 39 by means such as fitting only one end to the base of the reference shaft 39 in a tightened state. It is held so that it can be expanded and contracted without doing. The cover case 29 has two fitting holes 42 arranged on both sides of the bending piece 37 and fitted to the reference shaft 39, and two irregular holes 43 fitted to the stud 40. Has been formed. These irregular holes 43 are formed in the large-diameter portion 4 slightly larger than the diameter of the flange of the stud 40.
4 and a small diameter portion 45 smaller than the diameter of the flange.

Next, the attachment / detachment operation of the fixing unit 7 will be described. FIG. 2A shows a state in which the pullout member 33 is pulled out from the apparatus body 1. In this state, when the cover case 29 is placed on the placing surface 34 while inserting the bending piece 37 of the fixing unit 7 into the opening 38 of the pullout member 33,
As shown in (b), the stud 40 is attached to the cover case 29.
The large diameter portion 44 of the odd-shaped hole 43 is fitted. Then, when the pull-out member 33 is pushed toward the back of the apparatus main body 1, the fixing unit 7 stops because the contact portions 30 on both sides are brought into contact with the receiving portions 31. As shown in FIG. 3A, when the pullout member 33 is pushed further into the apparatus body 1, the pullout member 3 with the reference shaft 39 protruding into the fitting hole 42 of the cover case 29.
The locking portion 36 of No. 3 is locked by the lock mechanism of the apparatus main body 1. At this time, as shown in FIG.
Since 0 moves to the small diameter portion 45 of the odd-shaped hole 43, the flange holds the cover case 29 downward. In this state, the pull-out member 33 is locked by the lock mechanism, and the fixing unit 7 is stopped with the contact portion 30 supported by the receiving portion 31 by the pressing force of the coil spring 41. Therefore, as described above, the left and right abutting portions 30 are arranged on the same straight line parallel to the axial centers of the fixing rollers 26 and 27, and the left and right receiving portions 3 are provided.
Since No. 1 is also arranged on the same straight line parallel to the axis of the photoconductor 19, the axes of the fixing rollers 26 and 27 can be kept parallel to the axis of the photoconductor 19. As a result, it is possible to prevent the transfer sheet from curving and transfer the image on the photoconductor 19 to the transfer sheet with a line parallel to the front edge of the transfer sheet.

At the time of maintenance or the like, the locked state of the lock device is released from the state shown in FIG. 3 (a), and the pullout member 33 is pulled out to the side of the apparatus main body 1. In the initial stage of this pulling-out operation, that is, in the period until the reference shaft 39 comes off from the fitting hole 42 of the bending piece 37, the coil spring 41
Still presses the fixing unit 7 toward the receiving portion 31 side in a compressed state, the stud 40 causes the small diameter portion 4 of the irregular hole 43 to
5 to the large diameter portion 44. Still further, when the pullout member 33 is pulled out to the outside, the reference shaft 39 comes out of the fitting hole 42, the coil spring 41 extends, and the edge (drawout portion) 38a of the opening 38 presses the back surface of the bending piece 37. The fixing unit 7 moves outward together with the pullout member 33. In this state, the fixing unit 7 can be easily taken out above the pullout member 33. In the latter half of the pulling-out process of the pulling-out member 33, the stud 40 moves to the end of the deformed hole 43 in the pulling-out direction (on the side of the large diameter portion 44), so that the stud 40 can also be used as a pulling-out portion for pulling out the fixing unit 7. Is.

As described above, in the process of inserting the pullout member 33, the reference shaft 39 projects into the fitting hole 42 and the mounting surface 34 is placed.
Since the stud 40 moves to the small diameter portion 45 of the modified hole 43 and presses the floating of the fixing unit 7 from the mounting surface 34, the reference shaft 39 as a locking body is pressed. It is also possible to omit either one of the stud 40 and the stud 40.

[0015]

As described above, according to the present invention, in the insertion process of inserting the pull-out member on which the fixing unit is placed into the inner part of the main body of the apparatus, the fixing unit is pressed by the pressing portion and brought into contact with the receiving portion. In addition to determining the position in the insertion direction, the fixing unit is locked by the locking body so as to prevent the pulling member from floating from the mounting surface. Since it is pressed to pull out in the pulling direction and the locked state with the locking body is released, it is possible to easily attach and detach the fixing unit to and from the pulling member without using a tool, and to screw or the like. It is possible to avoid losing the fastening parts of the.

[Brief description of the drawings]

FIG. 1 shows an embodiment of the present invention and is an exploded perspective view showing a relationship between a fixing unit, a drawing member, and a receiving portion.

FIG. 2A is a vertical sectional front view showing the relationship between a fixing unit, a drawing member and a receiving portion, and FIG. 2B is a plan view of a part of FIG.

3A is a vertical cross-sectional front view showing a state where a fixing unit is completely attached, and FIG. 3B is a plan view of part of FIG.

FIG. 4 is a vertical sectional front view showing the internal structure of the electrophotographic apparatus.

[Explanation of symbols]

 A Electrophotographic device 7 Fixing unit 19 Photoconductor 31 Receiving part 33 Drawing member 39,40 Locking body 38a, 40 Drawing part 41 Pressing part

Claims (1)

[Claims] 1. An electrophotographic apparatus for transferring an image formed on a surface of a photoconductor by an electrophotographic method onto a transfer paper and then fixing the transferred image, wherein the transfer image on the transfer paper is attached to a main body of the electrophotographic apparatus. And a fixing unit for pressing the fixing unit in the insertion process of inserting a drawing member having a mounting surface for mounting the fixing unit for fixing the drawing unit so as to be drawn out, and inserting the drawing member into the apparatus main body. A locking member that engages with the fixing unit to prevent the fixing unit from floating from the mounting surface, and a pull-out portion that presses the fixing unit in the pull-out direction in the pull-out process of pulling out the pull-out member from the apparatus main body. The device main body is provided with a receiving portion which is provided on the drawing member and supports the fixing unit in the latter half of the insertion process of inserting the drawing member into the device main body. Child photography device.