JP2003249774A - Positioning mechanism and image forming equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a positioning mechanism which enables positioning simply, surely, detachably and high precisely. <P>SOLUTION: The positioning mechanism is equipped with a frame 81 for holding the positioning mechanism 81B and a positioning part 811B which engages with a member 11K to be positioned and positions the member. The positioning part 811B performs elastic deformation of a plastic deformation member 812 held by the frame 81 or the positioning part 811B, and is detachably fixed to the frame 81. A knob type cap part 814 is integrally formed. Only by an operation for rotating the cap part 814, the positioning part 811B engages with the member 11K to be positioned and performs positioning. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning mechanism and an image forming apparatus, and more particularly to a detachable positioning mechanism and an image forming apparatus using this positioning mechanism.

[0002]

2. Description of the Related Art Conventionally, as a detachable positioning mechanism, a positioning member or the like for positioning the unit with respect to the apparatus main body when the unit requiring the positioning accuracy in the image forming apparatus is detached for maintenance or the like. Need to be removed. When the positioning member is required to have high accuracy and high rigidity inside the device, the positioning member is fixed by using a screw or the like.

[0003]

However, a screwdriver is required to remove the screw, which is a factor that increases the amount of work of a worker who performs maintenance, and there is a possibility that the screw will loosen. There is a problem.

It is an object of the present invention to provide a positioning mechanism that can be easily and reliably positioned removably and with high accuracy, and also when a unit requiring positioning accuracy in an image forming apparatus is attached or detached for maintenance or the like. Another object of the present invention is to provide an image forming apparatus to which a positioning mechanism is applied in which the positioning member can be easily attached and detached even when the positioning member is required to have high precision and high rigidity inside the apparatus.

[0005]

The above object can be achieved by any of the following.

(1) In a positioning mechanism for removably positioning a member to be positioned, a frame for holding the positioning mechanism and a positioning portion for fitting and positioning the member to be positioned are provided. Elastically deforming an elastically deformable member held by the frame or the positioning portion and detachably fixed to the frame;
In addition, a positioning mechanism is characterized in that a knob-like cap portion is integrally formed and the cap member is fitted and positioned by the member to be positioned only by an operation such as rotating the cap portion.
(2) In an image forming apparatus that rotates a photosensitive drum to transfer a toner image formed on the surface to a sheet and fixes the transferred toner image on the sheet, a detachable unit formed in a process unit that can be pulled out from the apparatus body One end of the removable unit is supported by the support shaft of the apparatus main body, and the other end of the removable unit is supported by the positioning portion of the positioning mechanism described in (1), so that the removable unit is attached to the apparatus main body. An image forming apparatus characterized by positioning.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. In addition, X, Y shown in each drawing,
Regarding the Z direction, when viewed from the front of the color image forming apparatus of the embodiment, the right direction is the X direction and the left direction is the reverse X direction. Further, when viewed from the front, the upward direction is the Y direction, and the downward direction is the reverse Y direction. Further, when viewed from the front, the rear direction is the Z direction, and the front direction is the reverse Z direction.

FIG. 1 is a sectional view of a color image forming apparatus showing an example of an embodiment of the present invention. This color image forming apparatus is called a tandem type color image forming apparatus, and includes a plurality of sets of image forming units 10Y, 10M, and 10.
C, 10K, an intermediate transfer unit 7, a sheet feeding / conveying unit and a fixing unit 24. Image forming apparatus main body A
A document image reading device SC is arranged above the document.

Image forming unit 1 for forming a yellow image
0Y has a charging unit 2Y, an exposing unit 3Y, a developing unit 4Y, a primary transfer roller 5Y as a primary transfer unit, and a cleaning unit 6Y arranged around a photosensitive drum 1Y as a first image carrier. The image forming unit 10M that forms a magenta image includes a photosensitive drum 1M as a first image carrier, a charging unit 2M, an exposure unit 3M, a developing unit 4M, a primary transfer roller 5M as a primary transfer unit,
It has a cleaning means 6M. The image forming unit 10C that forms a cyan image includes a photosensitive drum 1C as a first image carrier, a charging unit 2C, an exposing unit 3C, a developing unit 4C, and a primary transfer roller 5 as a primary transfer unit.
C, and a cleaning means 6C. Further, the image forming unit 10K that forms a black image includes a photosensitive drum 1K as a first image carrier, a charging unit 2K, an exposing unit 3K, a developing unit 4K, and a primary transfer roller 5 as a primary transfer unit.
K, cleaning means 6K.

The intermediate transfer unit 7 has a semiconductive endless belt-shaped intermediate transfer member 70 as a second image bearing member which is wound by a plurality of rollers and is rotatably supported.

Image forming units 10Y, 10M, 10C, 10
The image of each color formed by K is the primary transfer roller 5Y,
By 5M, 5C, and 5K, the color images are sequentially transferred onto the rotating intermediate transfer member 70 to form a combined color image.
The paper P as a recording medium stored in the paper feed cassette 20 is fed by the paper feeding means 21, and the plurality of intermediate rollers 22A, 22B, 22C, 22D and the registration rollers 23 are provided.
After that, the color image is conveyed to the secondary transfer unit 5A, and the color image is collectively transferred onto the paper P. The paper P on which the color image is transferred is fixed by the fixing means 24, and the paper discharge roller 2
The sheet is sandwiched between the sheets 5 and placed on the sheet discharge tray 26 outside the machine.

On the other hand, after the color image is transferred onto the paper P by the secondary transfer means 5A, the residual toner is removed by the cleaning means 6A from the intermediate transfer body 70 in which the paper P is separated by the curvature. The residual toner is collected in a box by a device (not shown).

During the image forming process, the primary transfer roller 5K is constantly in pressure contact with the photosensitive drum 1K. The other primary transfer rollers 5Y, 5M, and 5C are in pressure contact with the corresponding photoconductor drums 1Y, 1M, and 1C only when forming a color image. The secondary transfer means 5A comes into pressure contact with the intermediate transfer body 70 only when the sheet P passes through here and secondary transfer is performed.

FIG. 2 is a perspective view showing a state in which the second process unit 9 is pulled out from the apparatus main body A of the image forming apparatus. The second process unit 9 includes a plurality of intermediate rollers 22A, 22B, 22C and 22D shown in FIG. 1, a registration roller 23, a secondary transfer means 5A, a fixing means 24 and the like.

FIG. 3 is a perspective view showing a state in which the first process unit 8 is pulled out from the apparatus main body A of the image forming apparatus,
FIG. 4 is a sectional view of the first process unit 8 accommodating the image forming portion, and FIG. 5 is a perspective view of the first process unit 8 accommodating the image forming portion.

As shown in FIGS. 3, 4 and 5, the first process unit 8 includes image forming units 10Y, 10M and 10M.
C, 10K, and an intermediate transfer unit 7.

Image forming units 10Y, 10M, 10C, 10
The Ks are arranged in a vertical column. Photoconductor drum 1
An intermediate transfer unit 7 is arranged on the left side of Y, 1M, 1C, and 1K in the drawing. The intermediate transfer unit 7 includes an endless belt-shaped intermediate transfer member 70, which is rotatable by winding rollers 71, 72, 73, 74, primary transfer rollers 5Y, 5
M, 5C, 5K, and cleaning means 6A.

The first process unit 8 can be pulled out from the apparatus main body A. That is, the front door 101 of the apparatus main body A
Is opened, and the unit handle members 88L and 88R formed on the first process unit 8 are grasped and pulled out to the front side.
The first process unit 8 includes the left and right support rails 82L,
Guided by 82R, it slides and is pulled out forward (reverse Z direction). By pulling out the first process unit 8, the image forming units 10Y, 10M, 10C, 10K,
The intermediate transfer unit 7 and the intermediate transfer unit 7 are integrally drawn out from the apparatus main body A.

The support rail 82L on the left side of the first process unit 8 in the figure is on the left side of the intermediate transfer member 70, and is located at the fixing unit 2.
4 is arranged in the upper space. The support rail 82R on the right side of the first process unit 8 in the figure is arranged near the lower part of the lowermost developing means 4K. Support rail 82R
Is arranged at a position where it does not interfere with the operation of attaching and detaching the developing means 4Y, 4M, 4C, 4K to the first process unit 8.

Photoreceptor drum 1 of the first process unit 8
To the right of Y, 1M, 1C, and 1K in the figure, there are developing means 4Y and 4Y.
The charging unit 2 is surrounded by M, 4C, and 4K, and the lower part in the drawing is a charging unit
Y, 2M, 2C, 2K, and cleaning means 6Y, 6
It is surrounded by M, 6C, 6K and the like, and the left side of the drawing is surrounded by the intermediate transfer member 70.

Among them, the photoconductor, the cleaning means, the charging means and the like form one photoconductor drum unit, and the developing means and the toner replenishing device etc. form one developing unit. This will be described in detail later.

The space above the photoconductor drum 1Y is shown in FIG.
As shown in, the frame 81 of the first process unit 8
It is shielded by a top plate 83 fixed as the upper shield member. The bottom plate 84 as a lower shielding member fixed to the frame 81 of the first process unit 8 protects the intermediate transfer body 70 at the time of attachment / detachment, and also serves as an upper guide plate of the paper transport path.

FIG. 6 shows the first process unit 8 through the intermediate transfer unit 7, and the developing units 4YU, 4MU, 4C.
FIG. 7 is an exploded sectional view showing a state in which U and 4KU are removed.
Is a perspective view of the intermediate transfer unit 7, and FIG. 8 is a perspective view of the first process unit 8. For convenience of description, the left half of the intermediate transfer body 70 is removed in FIG. 7 to make the inside of the intermediate transfer unit 7 easier to see.

As shown in FIGS. 6, 7 and 8, the first
In a state where the process unit 8 is pulled out from the apparatus main body A, the intermediate transfer unit 7 is slightly moved to the left in the figure, and then the intermediate transfer unit 7 is gripped and pulled up vertically. After the positioning pins 75 (FIG. 7) implanted in the upper portions of both side surfaces of the intermediate transfer unit 7 are moved leftward in the figure along the horizontal groove 85 (FIG. 8) formed in the first process unit 8. , Vertically upward along the vertical groove 86.

When the intermediate transfer unit 7 is pulled up, the positioning pin 75 of the intermediate transfer unit 7 has a horizontal groove 85,
The intermediate transfer member 70 is moved by being restricted by the vertical groove 86.
Does not contact the members of the first process unit 8 and are not damaged.

On the inner surface side of the intermediate transfer member 70, the primary transfer rollers 5Y, 5M, 5 supported horizontally as shown in FIG.
C, 5K and pressure rollers 76Y, 76M, 76C, 76
K and K are arranged in tandem. A lever 77Y supporting the primary transfer roller 5Y and the pressure roller 76Y, a lever 77M supporting the primary transfer roller 5M and the pressure roller 76M,
The primary transfer roller 5C and the lever 77C that supports the pressure roller 76C are simultaneously swung by the regulation plate 78 to press and release the intermediate transfer body 70.

FIG. 9 shows four pairs of photosensitive drum units 11.
It is a perspective view of Y, 11M, 11C, and 11K.

After removing the intermediate transfer unit 7 from the first process unit 8, four sets of photosensitive drum units 1 are provided.
1Y, 11M, 11C, and 11K have the pins 91 (FIG. 8) that are respectively suspended from the respective substrates 93Y and 93M.
It can be taken out by pulling out from the fitting holes 93A of 93C and 93K and the pin hole 81A (FIG. 8) provided in the frame 81 of the first process unit 8. The uppermost photosensitive drum unit 11Y includes a photosensitive drum 1Y, a charging unit 2Y, and a cleaning unit 6Y. The second-stage photoconductor drum unit 11M includes a photoconductor drum 1M, a charging unit 2M, and a cleaning unit 6M. Further, the third-stage photoconductor drum unit 11C includes the photoconductor drum 1
C, charging means 2C, and cleaning means 6C. Further, the lowermost photosensitive drum unit 11K includes a photosensitive drum 1K, a charging unit 2K, and a cleaning unit 6K.

When the first process unit 8 is pulled out from the main assembly A of the apparatus, as shown in FIG. 1, the drum drive shaft A on the main assembly side, which is cantilevered and fixedly supported inside the main assembly A of the apparatus, drives each photoconductor.
Photoconductor drum 1 from YD, AMD, ACD, AKD
Center holes 1YH, 1MH, 1C for Y, 1M, 1C and 1K
H and 1KH are released, and each photoconductor drum unit 11Y,
11M, 11C and 11K are fitted holes 93 of the substrates 93Y, 93M, 93C and 93K by the pins 91 fixed to the pin holes 81A of the frame 81 of the first process unit 8.
Move while being hung via A, and after moving, use pin 9
1 is removed from the first process unit 8 and removed, and the photoconductor drum units 11Y, 11M, 11C, 11K are provided at positions slightly floating from the regulation position by the pin 91 on the first process unit 8 (not shown). Each is mounted on a support.

In this state, the photosensitive drum unit 11Y can be slid on the support base and moved in the direction of the white arrow shown in FIG. 6 to take out the intermediate transfer unit 7 from the space after removal. Photoconductor drum unit 11M,
Similarly, 11C and 11K can be taken out from the respective support bases.

A developing unit 4YU mainly composed of the developing means 4Y facing the photosensitive drum unit 11Y, a developing unit 4MU mainly composed of the developing means 4M facing the photosensitive drum unit 11M, and a developing means 4C facing the photosensitive drum unit 11C. Main development unit 4C
U, developing means 4 facing the photoconductor drum unit 11K
The developing unit 4KU having K as a main component can be taken out from each of the predetermined storage units of the first process unit 8 after being slightly moved to the right as shown in FIG. 6 and then pulled forward (in the reverse Z direction). .

A support rail 82 for supporting the first process unit 8
Slide along L and 82R, and mount into the device main body A.
Stop at a predetermined position, and unit handle members 88L, 88R
It is fixed by a lock lever (not shown) by rotating 90 °. The operation detecting means of the first process unit 8 detects by a sensor that detects that the first process unit 8 is attached to a predetermined position of the apparatus main body A. Alternatively, the process unit operation detecting means detects that the lock lever has completed a predetermined operation.

In the above embodiment, the seamless endless belt-shaped intermediate transfer member 70 has been described. However, the present invention is not limited to this, and the endless belt-shaped intermediate transfer member having a seam. It is also applicable to.

Although the configuration of the color image forming apparatus has been described above, the present invention is not limited to the color image forming apparatus, but can be applied to a monochrome image forming apparatus as well. Only one photoconductor drum unit and one developing unit are required in the process unit, an intermediate transfer member is not required, and a toner image may be directly transferred onto a recording paper which is a secondary transfer member.

Therefore, in the following more detailed description, the four photosensitive drum units are exactly the same, so only one set of K will be described.

FIG. 10 is a sectional view showing the construction of the photosensitive drum unit 11K and the first positioning mechanism 81B arranged in the first process unit 8, and FIG. 11 is a sectional view showing the construction of the first positioning mechanism 81B. FIG. 12 is an exploded perspective view of the first positioning mechanism 81B.

As shown in FIGS. 10, 11 and 12, the first process unit 8 can be pulled out from the apparatus main assembly A, and the first process unit 8 is provided with a photosensitive drum unit 11K. When the first process unit 8 is stored in the apparatus main body A, the photosensitive drum unit 11K is
First positioning mechanism 81B and main body side drum drive shaft AKD
Positioned by and.

The first positioning mechanism 81B is composed of a cap portion 814, a leaf spring 812, a hooking claw portion 813, a positioning portion 811B and the like.

The frame 81 holds a positioning mechanism.
The knob-shaped cap portion 814 is arranged on one surface of the frame 81. The positioning portion 811B is disposed on the other surface of the frame 81, is integral with the frame 81, and fits on a member to be positioned for positioning. The hooking claw portion 813 is screwed by a screw 816 and integrated with the cap portion 814.

The leaf spring 812, which is an elastically deformable member, is fixed to the other surface of the frame 81 with a screw 815, and is provided between the cap portion 814 and the hooking claw portion 813.
The rotation of 3 causes elastic deformation to fix the positioning portion 811B to the frame 81 in a detachable manner.

With the positioning portion 811B fixed to the frame 81, the two hooking claw portions 813 provided at symmetrical positions are in the horizontal position (X direction) and support the photosensitive drum 1K which is the member to be positioned.

When the rectangular tip of the cap portion 814 is in the X direction, the positioning portion 811B causes the frame 81 to move.
Fixed to.

The positioning portion 8 is provided in the hole formed in the frame 81.
A part of 11B is fitted to position the positioning portion 811B with respect to the frame 81.

To remove the photosensitive drum unit 11K,
In a state where the first process unit 8 is pulled out from the apparatus main body A, the cap portion 814 can be rotated clockwise to remove the positioning mechanism 81B, and then the cap unit 814 can be taken out.

Next, the second positioning mechanism will be described. FIG. 13 is a sectional view showing the configuration of the intermediate transfer unit 7 and the second positioning mechanism 81C arranged in the first process unit, and FIG. 14 is a sectional view showing the configuration of the second positioning mechanism 81C. The parts that are mechanically similar to those of the first positioning mechanism are designated by the same reference numerals and the description thereof is partially omitted.

As shown in FIGS. 13 and 14, the first process unit 8 can be pulled out from the main assembly A of the apparatus.
The process unit 8 is provided with the intermediate transfer unit 7. When the first process unit 8 is housed in the apparatus main body A, the intermediate transfer unit 7 is positioned by the second positioning mechanism 81C and the main body side pin AP (FIG. 13).

The second positioning mechanism 81C is composed of a cap portion 814, a leaf spring 812, a hooking claw portion 813, a positioning portion 811C and the like.

The frame 81 holds a positioning mechanism.
The knob-shaped cap portion 814 is arranged on one surface of the frame 81. The positioning portion 811C is disposed on the other surface of the frame 81, is integrated with the cap portion 814, and is fitted into the frame 79 that is a member to be positioned for positioning. The hooking claw portion 813 is screwed by a screw 816 and integrated with the cap portion 814.

Further, a leaf spring 812 which is an elastically deformable member.
The other surface of the frame 81 is provided between the frame 81 and the hooking claw portion 813, and is elastically deformed by the rotation of the hooking claw portion 813 to detachably fix the positioning portion 811C to the frame 81. With the positioning portion 811C fixed to the frame 81, the two hooking claw portions 813 provided at symmetrical positions are provided.
Is in a horizontal position and supports a frame 79 which is a member to be positioned. Depending on the orientation of the rectangular tip of the cap portion 814, it is possible to detect whether the positioning portion 811C is fixed to the frame 81 in a completed state or an incomplete state. A part of the positioning portion 811C is fitted into the hole formed in the frame 81 to position the positioning portion 811C with respect to the frame 81.

The intermediate transfer unit 7 can be taken out after the first process unit 8 is pulled out from the apparatus main body A, the cap portion 814 is rotated clockwise, and the positioning mechanism 81C is removed. ing.

[0051]

The above-mentioned structure has the following effects.

According to the first and second aspects of the invention, since the member to be positioned is positioned by the removable positioning member, it is possible to provide a positioning mechanism capable of positioning the member in a highly accurate, reliable and removable manner.

According to the third aspect of the invention, since the two hooking claws provided at symmetrical positions are in the horizontal position when the positioning part is fixed to the frame, the force applied to the hooking claws is equalized. It will be fixed securely.

According to the fourth aspect of the invention, it is possible to detect whether the positioning portion is fixed to the frame in the completed state or the incomplete state, depending on the direction of the cap portion, so that the setting is reliable.

According to the invention of claim 5, a part of the positioning portion is fitted into the hole formed in the frame to position the positioning portion with respect to the frame, so that the positioning accuracy of the positioning portion with respect to the frame is accurate. it can.

According to the sixth aspect of the invention, one end of the detachable unit formed in the process unit that can be pulled out from the apparatus body is supported by the support shaft of the apparatus body, and the other end of the detachable unit is connected. The positioning unit of the positioning mechanism according to any one of claims 1 to 5 supports the removable unit to position the detachable unit with respect to the apparatus main body, and thus requires positioning accuracy in the image forming apparatus for maintenance or the like. Even when the positioning member is required to have high accuracy and high rigidity when the unit is attached and detached, the image forming apparatus can easily attach and detach the positioning member.

According to the seventh aspect of the invention, the detachable unit can be easily attached and detached in the photosensitive drum unit or the intermediate transfer unit.

[Brief description of drawings]

FIG. 1 is a cross-sectional configuration diagram of a color image forming apparatus showing an example of an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which a second process unit is pulled out from the main body of the image forming apparatus.

FIG. 3 is a perspective view showing a state in which a first process unit is pulled out from the apparatus body of the image forming apparatus.

FIG. 4 is a cross-sectional view of a first process unit accommodating an image forming unit.

FIG. 5 is a perspective view of a first process unit accommodating an image forming unit.

FIG. 6 is an exploded cross-sectional view showing a state in which an intermediate transfer unit and a developing unit are removed from the first process unit.

FIG. 7 is a perspective view of an intermediate transfer unit.

FIG. 8 is a perspective view of a first process unit.

FIG. 9 is a perspective view of four photosensitive drum units.

FIG. 10 is a sectional view showing a configuration of a photosensitive drum unit arranged in a first process unit and a first positioning mechanism.

FIG. 11 is a sectional view showing a configuration of a first positioning mechanism.

FIG. 12 is an exploded perspective view of a first positioning mechanism.

FIG. 13 is a cross-sectional view showing a configuration of an intermediate transfer unit and a second positioning mechanism arranged in the first process unit.

FIG. 14 is a cross-sectional view showing a configuration of a second positioning mechanism.

[Explanation of symbols]

1Y, 1M, 1C, 1K Photosensitive drum 7 Intermediate transfer unit 8 First process unit 81 frames 93A fitting hole 811B, 811C Positioning part 812 Leaf spring (elastically deformable member) 813 Hooking claw 814 Cap section A device body AYD, AMD, ACD, AKD Body side drum drive shaft

Continued front page    F-term (reference) 2H071 BA03 BA04 BA13 BA14 BA16                       BA29 DA06 DA08 DA09 DA13                       DA15                 4E353 AA01 BB02 CC02 CC11 CC12                       CC16 DD02 DD05 DD06 DD14                       DR06 DR09 DR23 DR27 DR29                       DR32 DR36 DR46 DR49 GG09                       GG16 GG21

Claims (7)

[Claims] 1. A positioning mechanism for removably positioning a member to be positioned, comprising a frame for holding the positioning mechanism, and a positioning portion for fitting and positioning the member to be positioned, wherein the positioning portion comprises: The elastic deformation member held by the frame or the positioning portion is elastically deformed to be detachably fixed to the frame, and a knob-shaped cap portion is integrally formed to rotate the cap portion. A positioning mechanism for fitting and positioning the member to be positioned. 2. A cap portion integrally formed with a hooking claw portion is disposed on one surface of the frame, the positioning portion is disposed on the other surface of the frame, and the elastically deformable member is the frame. The positioning mechanism according to claim 1, wherein the positioning mechanism is provided on the other surface of the frame between the frame and the hooking portion. 3. The positioning mechanism according to claim 2, wherein the two hooking claws provided at symmetrical positions are in a horizontal position when the positioning part is fixed to the frame in a completed state. 4. The method according to claim 1, wherein it is possible to detect whether the positioning portion is in a fixing completed state or an uncompleted state on the frame depending on the orientation of the cap portion. The described positioning mechanism. 5. The positioning mechanism according to claim 1, 2 or 3, wherein a part of the positioning part is fitted into a hole formed in the frame to position the positioning part with respect to the frame. . 6. An image forming apparatus for rotating a photosensitive drum to transfer a toner image formed on a surface to a sheet and fixing the transferred toner image to the sheet, the image forming apparatus being formed in a process unit that can be pulled out from an apparatus main body. The one end of the detachable unit is supported by a support shaft of the main body of the apparatus, and the other end of the detachable unit is supported by the positioning portion of the positioning mechanism according to any one of claims 1 to 5, and the detachable unit is supported. An image forming apparatus in which a flexible unit is positioned with respect to the apparatus main body. 7. The detachable unit is a photosensitive drum unit including a photosensitive drum or an intermediate transfer unit including an intermediate transfer belt.
The image forming apparatus according to item 1.