JP2659717B2 - Image forming unit attaching / detaching device in image forming apparatus - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image forming unit attaching / detaching device in an image forming apparatus, and more specifically, can be widely applied to image forming apparatuses such as various printers and copiers using an electrophotographic system. The present invention relates to an image forming unit attaching / detaching device in an image forming apparatus.

(Prior Art) In an image forming apparatus using an electrophotographic method, for example, a non-impact printer, an electrophotographic copying machine, or the like, each process of charging, exposure, development, transfer, and cleaning is performed around a photosensitive drum. An image is recorded.

In the image forming apparatus, there is a strong demand for so-called user maintenance, such as replacing the toner on the developing device for performing the developing process, the photosensitive drum, and even the cleaning device for performing the cleaning process on the user side, There is a demand for a device configuration that can be easily converted into a unit.

In order to respond to the above demands, a photosensitive drum, a developing device,
There is a method in which a cleaning device, a charger for a charging process, and the like are integrally mounted on an image forming unit, and after a certain period of time, the entire image forming unit is replaced.

However, in this case, the cost of one exchange is high, and the burden on the user eventually increases. This is because the life of the photoconductor, the toner supply interval, the life of the creasing unit, and the like are different from each other. For example, even if there is a photoconductor that can be used sufficiently, it is replaced together with this integrated image forming unit. It has been pointed out that the running cost per sheet becomes extremely high.

Therefore, a method has been proposed in which a replacement cycle of each device such as a developing device and a cleaning device is set on the image forming unit, and each device is separately taken out from the image forming unit and replaced.

However, even in this method, the position of each device in the image forming apparatus is accurately determined, and the photosensitive drum is damaged when each device is replaced. If the separation is performed manually and roughly, the toner accumulated between the photosensitive drum and the cleaning brush may spill out. In addition, there is another inconvenience such as forgetting to set the cleaning device to an appropriate cleaning position after replacing the cleaning device.

(Purpose) Accordingly, an object of the present invention is to provide at least an image forming apparatus that performs at least development, transfer, and cleaning processes around an image forming drum to record an image. The apparatus is mounted on the same image forming unit, at least the cleaning device is detachable with respect to the image forming unit, and the image forming unit is detachable with the image forming unit pulled out from the image forming apparatus. It is an object of the present invention to provide an image forming unit attaching / detaching device in an image forming apparatus which can prevent toner spillage when replacing a cleaning device and prevent a setting failure of the cleaning device.

(Structure) In order to achieve the above object, the present invention performs at least the development, transfer, and cleaning processes around the image forming drum to perform image recording and performs the image forming drum and the cleaning process in an image forming apparatus. Cleaning device is attached to the same image forming unit, at least the cleaning device is detachable from the image forming unit, and the image forming unit is pulled out from the image forming device. In a detachable image forming apparatus, a slide member having a concave portion opened at an upper portion for detachably supporting a shaft portion of the cleaning device is included, and the slide member includes a cleaning position from a separated position of the cleaning device. Guide means for slidably guiding the area, and cleaning the slide member An urging means for urging toward the posture, and a shaft member of the cleaning device which is opened in the separated posture to surround the cleaning device so as not to be pulled out upward in the cleaning posture and the slide member by the urging means And a groove for preventing movement of the cleaning member and positioning the cleaning position.

That is, in the present invention, the image forming unit can be integrally pulled out from the image forming apparatus main body, and the individual units can be replaced under the pulled-out state. At this time, the cleaning unit can be replaced after the cleaning unit is separated from the photosensitive drum by operating the locking means with the image forming unit pulled out. When the image forming unit is set in the image forming apparatus main body, the cleaning unit can be automatically moved to a proper position with respect to the photosensitive drum.

Hereinafter, a specific description will be given based on an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a case housing an image forming unit.

As shown in FIGS. 5 and 6, the case 1 is provided with a photosensitive drum 2, a developing device 3, a cleaning device 4 and the like so as to be detachable, and constitutes an image forming unit as a whole.

Note that the toner cartridge 3A can be further disassembled from the developing device 3.

Case 1 is shown in FIG. 1 and FIG.
In the figure, the handle 5 is slidable in the direction of
6 (see FIG. 6) and can be removed from the image forming apparatus 28.

The guide means at the time of sliding is indicated by reference numeral 7 in FIGS.

In FIG. 1, two L-shaped sliders 8 and 9 as slide members are slidably mounted in one direction on a bottom plate 1A of a case 1 by set screws 10.

That is, the sliders 8 and 9 are formed with long holes 11 in the direction B perpendicular to the arrow A on the bottom plate 1A.
Set screw 10 is screwed into the bottom plate through 11 (No. 3
See figure).

The sliders 8 and 9 have U-shaped grooves 81M and 91M in the bent pieces 81 and 91, respectively, and pins 81P and 91P as the shafts of the cleaning device 4 engage with the grooves 81M and 91M, respectively. It has become.

Groove blocks 12, 1 on the bottom plate 1A on each outside of the bent pieces 81, 91
The pins 81P are engaged with the grooves 81M, and are also engaged with the grooves 15M of the groove block 15.

Similarly, the pin 91P engages with the groove 91M and also engages with the groove 13M of the groove block 13.

The other pin 92P of the cleaning device 4 is the groove block 1
The second pin 12P engages with the second groove 12M, and a pin (not shown) provided at a position facing the pin 92P engages with the groove 14M of the groove block 14.

Thus, the cleaning device 4 is provided with the groove blocks 12, 13, 14, 1
When the sliders 8 and 9 move, they are stably supported by 5 and move in the direction of arrow B accordingly.

In FIG. 1, a photosensitive drum (not shown) is located on the right side in the direction of arrow B, and movement of sliders 8 and 9 guided and slid by set screws 10 and elongated holes 11 as guide means. Accordingly, when the pins 81P and 91P are abutted against the groove ends of the grooves 13M and 15M, the cleaning brush 16 of the cleaning device 4 comes into contact with the peripheral surface of the photosensitive drum in a state capable of cleaning. The attitude of the cleaning device 4 at this time is called a cleaning attitude.

Conversely, when the sliders 8, 9 move to the left in the direction of arrow B, the cleaning device 4 separates from the photosensitive drum. The attitude of the cleaning device 4 at this time is referred to as a separated attitude.

In the above separated position, each pin 81 of the cleaning device 4
P, 91P, 92P, etc. are located at positions deviated from the respective grooves of the groove blocks 12 to 15, and the cleaning device 4 can be removed upward, and after removal, can be repaired or replaced.

Next, the shaft 17 is pivotally supported in the direction of arrow A through the wall of the case 1.

Cams 18 and 19 having the same shape and the same size are fixed to the intermediate portion of the shaft 17 and at positions facing the upright wall portions 8W and 9W of the sliders 8 and 9, respectively.

A leaf spring 20 is provided on the shaft 17 between the cams 18 and 19.
21 are installed.

According to the rotation of the shaft 17, the cams 18, 19 are turned upright wall portions 8W, 9W.
Or the leaf springs 20, 21 push the rear wall 4W of the cleaning device 4.

In FIG. 1, the shaft 17 is turned counterclockwise to put the cleaning device 4 in the separated position. Then cam 18,1
The free end of 9 pushes and moves the upright wall portions 8W and 9W, and the sliders 8 and 9 on which the cleaning device 4 is mounted are separated from the photosensitive drum.

Conversely, to set the cleaning device 4 in the cleaning position, the shaft 17 is turned clockwise. Then, the free ends of the leaf springs 20 and 21 push and move the rear wall 4W, and the pins 9 are inserted into the groove ends of the grooves 13M and 15M.
The cleaning device 4 is positioned at the cleaning position where 1P and 81P are abutted.

Next, an open leg spring 22 is wound around the shaft 17. One end of the open leg spring 22 is hung on the free end of the cam 19, and the other end is in contact with the bottom plate 1A.

The shaft 17 is urged in the counterclockwise direction in FIG. 1 by the elasticity of the open leg spring 22. The rotation of the cams 18, 19 due to the urging force is prevented by the ends of the long holes 11 of the sliders 8, 9 abutting against the set screw 10. The attitude of the cleaning device 4 at this time corresponds to the separated attitude (see FIG. 2A).

Next, a lever 23 is mounted on the shaft 17 and outside the wall of the case 1. A pin 23P is implanted at a free end of the lever 23.

A lock lever 24 is pivotally attached to the wall of the case 1 on the swing trajectory of the pin 23P with the rotation of the shaft 17. The lock lever 24 has a guide surface 24A, a concave portion 24B, and a handle 24C, and is urged in a counterclockwise direction by an elastic spring 25.

When the cleaning device 4 is in the separated position, the lock lever 24 is prevented from rotating by the urging force by an appropriate stopper so that the guide surface 24A of the lock lever 24 is positioned on the swing locus of the pin 23P. I have.

Thus, when the shaft 17 is rotated clockwise, the cleaning device 4 shifts to the cleaning position. In the process, the pin 23P interferes with the guide surface 24A. It engages with the recess 24B by the action (see FIG. 4).

Once the pin 23P is engaged with the recess 24B in this manner, the leaf spring
The pin 23P is locked to the lock lever 24 by the urging force of the opening springs 20, 21 and the opening spring 22, and the pressing force by the leaf springs 20, 21 as urging means for urging the sliders 8, 9 toward the cleaning position. Then, the cleaning device 4 is held in the cleaning position (see FIG. 2 (b)).

To release the cleaning device 4 from the cleaning position, the user grasps the handle 24C by hand, rotates the lock lever 24 clockwise against the elasticity of the spring 25, and releases the pin 23P from the recess 24B. I just need.

Then, the shaft 17 rotates in the counterclockwise direction by the action of the open leg spring 22, and the cams 18, 19 push the upright walls 8W, 9W to move the cleaning device 4 to the separated position.

In the above description, the sliders 8 and 9, the cams 18 and 19, the leaf springs 20 and 21, and the groove blocks 12, 13, 14, and 15 can freely convert the cleaning device 4 into the cleaning position or the separated position. It is a main component of the conversion means.

The lever 23 and the lock lever 24 are main constituent members of lock means capable of holding and releasing the cleaning device 4 in the cleaning state.

Next, in FIG. 1, a three-dimensional cam 26 is provided integrally with the shaft 17 outside the wall of the case 1 as an extension of the shaft 17.

This three-dimensional cam 26 has a groove 26M in the axial direction on the surface of a cylinder.
The groove 26M has one surface 26M1 of the groove parallel to the axial direction and the opposing surface 26M2 spirally opened.

On the other hand, the image forming apparatus main body 28 (see FIGS. 5 and 6) is provided with a pin 27 that can be engaged with the groove 26M.

The pin 27 is engaged with the guide means 7 shown in FIGS.
M is the portion having the widest groove width, and is in a related position in contact with the facing surface 26M2.

Therefore, when the case 1 is pushed rightward in FIG. 1 from this state, the pin 27
Since the cylindrical cam 26 is pressed against the 26M2, the cylindrical cam 26 is rotated clockwise by the pin 27 according to the spiral surface of the facing surface 26M2, and the cleaning device 4 is set to the cleaning position as the case 1 is pushed in. Further, the lever 23 is locked by the lock lever 24, and the above-described cleaning state is maintained.

That is, as long as the cleaning device 4 is set in the case 1, the cleaning device 4 is set to an appropriate cleaning position in accordance with the operation of attaching the case 1 to the image forming apparatus main body.
Means that the positioning is maintained.

On the other hand, when the case 1 is removed from the image forming apparatus main body 1, the case 1 linearly moves in the direction of arrow A along the guide means 7, and the pin 27 only moves relatively along the one surface 26M1. Attitude remains retained.

After the case 1 is completely separated from the image forming apparatus main body 28 in this way, if the handle 24C of the lock lever 24 is operated, the cleaning device 4 can be set to the separated state.

Thus, the three-dimensional cam 26 and the pin 27 constitute an interlocking positioning means for bringing the cleaning device 4 into the cleaning state and holding the same in conjunction with the mounting operation of the case 1.

In the above example, when putting the case 1 in and out, the lever
Since the cleaning device 4 does not separate from the photosensitive drum unless the knob 23 is turned, inadvertent toner spillage between the cleaning device 4 and the photosensitive drum can be minimized.

Also, even if the user does not turn the lever 23,
After the cleaning device 4 has been replaced, the cleaning device can be automatically set to a predetermined cleaning position in conjunction with the operation simply by placing the case 1 in the image forming apparatus main body. The set position can be set without mistake.

In FIG. 5, reference numeral 30 denotes an optical system unit incorporating a light source, a mirror, and the like, and reference numerals 31 and 32 denote a static elimination charger and a charging charger attached to the optical system unit 30, respectively. A document G is placed on the upper surface of the optical system unit 30.

Reference numeral 33 denotes a transfer charger, which is attached to the case 1 of the image forming unit.

Further, reference numerals 34 and 35 denote paper feed cassettes, reference numeral 36 denotes a registration roller, reference numeral 37 denotes a transport belt, reference numeral 38 denotes a fixing device, reference numeral 39 denotes a copy tray for discharging a copied sheet (see FIG. 6).
The transporting machine for transporting to each is shown.

(Effect) According to the present invention, when replacing the cleaning device,
This is advantageous in that toner spillage can be avoided and the setting failure of the cleaning device can be prevented.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a main part of an image forming unit attaching / detaching apparatus according to the present invention, FIG. 2 is a front view of the same figure, FIG.
FIG. 4 is a front view around the lock lever, FIG. 5 is a schematic configuration diagram of an image forming apparatus suitable for carrying out the present invention, and FIG. 6 is an external perspective view of the image forming apparatus according to the above figure. 4 ... cleaning device, 8, 9 ... slider (as a slide member), 10 ... set screw (as a guide means), 11 ... long hole (as a guide means), 20 ... (biasing means) Leaf spring, 15M ... groove, 81P, 91P ... pin (as shaft of cleaning device).

Claims (1)

(57) [Claims] 1. An image forming apparatus according to claim 1, wherein said image forming drum and said cleaning device for executing said cleaning process in an image forming apparatus for performing image recording by executing at least development, transfer and cleaning processes around the image forming drum. Attached to the image unit, at least the cleaning device is removable with respect to the image forming unit,
In the image forming apparatus, wherein the image forming unit is detachable under a state where the image forming unit is pulled out from the image forming apparatus, a slide member having a concave portion opened at an upper portion to detachably support a shaft portion of the cleaning device, Guide means for slidably guiding the slide member in a region including the cleaning position from the separated position of the cleaning device; urging means for urging the slide member toward the cleaning position; and the cleaning device. The shaft part is opened in the above separated position,
An image forming unit in the image forming apparatus, wherein the image forming unit is provided with a groove for enclosing the slide member so that the slide member does not come off in the cleaning position and for preventing movement of the slide member by the urging means and positioning the slide member in the cleaning position. apparatus.