JPH11223993A - Image forming device of electrophotographic system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit, in an image forming device of an electrophotographic system, the transmission of the driving force of a device main body to a replacement unit without increasing the cost of manufacture and maintenance, and the size of the device main body. SOLUTION: A replacement unit is provided so as to be freely attached/ detached to/from an image forming device main body by being inserted/ withdrawn in the direction of the sleeve shaft of a developing sleeve. Inside the device main body are a bearing which receives the sleeve shaft When the replacement unit is attached; a drive gear 13 which allows the insertion of the sleeve shaft into an engagement hole 13a in the center of rotation, according to the insertion/withdrawal of the replacement unit, thereby engaging with the sleeve shaft so as to transmit the rotation, or allows the withdrawal of the sleeve shaft, thereby releasing the engagement; a swing member 18 which swings according to the insertion/withdrawal of the replacement unit; and a drive transmission gear 19 which is freely and rotatably supported by the swing member 18, and moves as the swing member 18 swings, thereby engaging/ disengaging with/from the drive gear 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer, a facsimile or a multifunction machine using a laser, in which charging, optical writing, development, transfer, cleaning, static elimination, etc. are repeated on an image carrier in order. The present invention relates to an electrophotographic image forming apparatus that forms an image, sequentially transfers the image, and records the image on a recording medium such as a sheet or a card.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 11 and 12, for example, as shown in FIGS. 11 and 12, at least a developing device is provided in this type of electrophotographic image forming apparatus to constitute a replacement unit 1. In some cases, the exchange unit 1 is inserted into and removed from the developing sleeve of the developing device in the axial direction of the developing sleeve, and is attached to and removed from the image forming apparatus main body.

In the conventional image forming apparatus shown in FIG. 11, one end of a sleeve shaft 3a is provided so as to protrude from a unit case 2 at the front end side of the mounting of the replacement unit 1, and a drive gear 4 is provided on one end of the protruding sleeve shaft 3a. , A drive transmission gear 5 that meshes with the drive gear 4 is supported, and a coupling member 6 is provided coaxially with a gear (not shown) that meshes with the drive transmission gear 5.

When the replacement unit 1 is mounted on the main body of the image forming apparatus, the coupling member 6 is connected to the coupling member 7 of the main body of the apparatus, and the main motor 9 is connected while the clutch 8 is connected and disconnected. The rotation is transmitted to a gear (not shown) of the exchange unit 1 via the coupling members 6 and 7, transmitted from the gear to the drive gear 4 via the drive transmission gear 5, and rotates the developing sleeve together with the sleeve shaft 3 a. Was.

In the conventional image forming apparatus shown in FIG. 12, a developing sleeve 3 is provided in a unit case 2 of a replacement unit 1, one end of the developing sleeve 3 protrudes from the unit case 2, and the projecting developing sleeve 3 The coupling member 6 is provided directly on one end of the.

When the replacement unit 1 is attached to the image forming apparatus main body, the coupling member 6 is connected to the coupling member 7 on the apparatus main body side, and the main motor 9
Is transmitted to the exchange unit 1 via the coupling members 6 and 7, and the developing sleeve 3 is directly rotated.

[0007]

However, in the conventional image forming apparatus as described above, since the driving force of the apparatus main body is transmitted to the exchange unit 1 via the coupling members 6 and 7, these couplings are not provided. Because of the provision of the members 6 and 7,
There is a problem that the number of parts is increased and the cost is increased, and a space is required in a direction in which the replacement unit 1 is put in and taken out, so that the apparatus body becomes large.

In addition, in the conventional image forming apparatus as shown in FIG. 11, the exchange unit 1 is provided with a drive transmission gear 5 and a drive transmission gear 5 and a gear (not shown) that meshes with the drive gear 4 so that the exchange unit 1 is a consumable part. However, there is a problem that the number of parts increases and the cost increases, and the maintenance cost increases.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrophotographic image forming apparatus as described above without increasing costs, increasing maintenance costs, or increasing the size of the apparatus main body. Is transmitted to the exchange unit.

[0010]

Therefore, according to the present invention, at least a developing device is provided in an electrophotographic image forming apparatus as in an embodiment described with reference to FIGS. A replacement unit which is provided in the developing device so as to be inserted into and removed from the image forming apparatus main body in a direction of a sleeve axis 20 of the developing device, and which is provided in the apparatus main body, and the sleeve is provided when the replacement unit is mounted. Bearing 12 for receiving shaft 20
A sleeve shaft 20 of the developing sleeve, which is provided in the apparatus main body and has an engagement hole 13a at the center of rotation, and the sleeve shaft 20 of the developing sleeve is inserted into the engagement hole 13a in accordance with insertion and removal of the replacement unit. A drive gear 13 that is engaged with the transmission shaft or that pulls out the sleeve shaft 20 to release the engagement, and a swing member 18 that is provided in the apparatus main body and swings according to the insertion and removal of the exchange unit. And a drive transmission gear 19 rotatably supported by the swing member 18 and moving with the swing of the swing member 18 to mesh with the drive gear 13 or cancel the mesh. It is characterized by.

According to the first aspect of the present invention,
When removing the replacement unit from the image forming apparatus main body, the replacement unit is moved in the direction of the sleeve shaft 20 and the drive gear 1 is moved.
3, the sleeve shaft 20 of the developing sleeve is pulled out from the engagement hole 13a to release the engagement, the pulling out from the bearing 12, and the swinging member 18 is swung to move the drive transmission gear 19 so that the drive transmission gear 19 and the drive gear 13 are moved. Release the engagement.

When the replacement unit is mounted on the main body of the image forming apparatus, the replacement unit is mounted in the direction of the sleeve shaft 20, and the sleeve shaft 20 of the developing sleeve is inserted into the engagement hole 13a of the drive gear 13 so that the drive gear 13 is connected to the sleeve. Axis 2
In addition to the engagement with the transmission gear 0, the sleeve shaft 20 is received by the bearing 12, and then the swinging member 18 is swung to move the drive transmission gear 19 and mesh with the drive gear 13.

According to a second aspect of the present invention, in the electrophotographic image forming apparatus according to the first aspect, as in the embodiment described with reference to FIGS. The drive transmission gear 19
It moves in the direction of the sleeve shaft 20 by receiving a force accompanying the rotation of the shaft, and is positioned against the bearing 12 in the thrust direction.

In the invention according to claim 2,
When the main body of the image forming apparatus is driven, the driving gear 13 is moved in the direction of the sleeve shaft 20 by receiving the force accompanying the rotation of the driving transmission gear 19, and is positioned in the thrust direction by contacting the bearing 12.

According to a third aspect of the present invention, there is provided an electrophotographic image forming apparatus having at least a developing device as in an embodiment described with reference to FIG. 6, for example, and a developing sleeve provided in the developing device. An exchange unit which is inserted and removed in the direction of the sleeve shaft 20 so as to be attached to and detached from the image forming apparatus main body, and an engaging member 33 which is provided integrally or separately at the tip of the sleeve shaft 20 and rotates together with the sleeve shaft 20. It is rotatably supported in the apparatus main body, and has an engaging portion 13d between a rotation center and an outer peripheral tooth portion,
A drive gear 13 that engages with the engagement portion 13d so as to transmit the rotation of the engagement member 33 to the sleeve shaft 20 according to the insertion and removal of the exchange unit, or releases the engagement.
And comprising:

According to the third aspect of the present invention,
When removing the replacement unit from the image forming apparatus main body, the replacement unit is moved in the direction of the sleeve shaft 20 and the drive gear 1 is moved.
The engagement of the engagement member 33 with the third engagement portion 13d is released and taken out from the apparatus main body.

When the replacement unit is mounted on the main body of the image forming apparatus, the replacement unit is inserted in the direction of the sleeve shaft 20 to engage the engagement member 33 with the engagement portion 13d of the drive gear 13 to rotate the drive gear 13. Transmission to the sleeve shaft 20 is enabled.

According to a fourth aspect of the present invention, in the electrophotographic image forming apparatus according to the third aspect, as in an embodiment described with reference to FIG. 6, for example, the drive gear 13 is a helical gear. It is supported by a support shaft 31 and is slidably provided in the sleeve shaft 20 direction.

In the invention according to the fourth aspect,
When the image forming apparatus main body is driven, the driving gear 13 receives a force from the rotation of the transmission gear to rotate the driving gear 13 to the support shaft 1.
3 is moved in the direction of the sleeve shaft 20 so that the engagement portion 13 d of the drive gear 13 does not come off the engagement member 33.

According to a fifth aspect of the present invention, in an electrophotographic image forming apparatus, at least a developing device is provided as in an embodiment described with reference to FIGS. An exchange unit which is inserted into and removed from the developing sleeve 42 in the direction of the sleeve axis 20 and is attached to and removed from the image forming apparatus main body; a drive gear 13 which is fixed to the sleeve shaft 20 of the exchange unit; When the replacement unit is inserted into the main body and moves in a direction perpendicular to the sleeve shaft 20, a side plate 10 having a bearing portion 10c for receiving the sleeve shaft 20 is provided in the apparatus body, and the replacement unit is mounted. A swing member 18 that swings when the replacement unit is moved in a direction perpendicular to the sleeve shaft 20 in accordance with the removal; MEMBER rotatably supported at 18, the rocking member 18 the drive gear 13 to move with the swinging of the
And a drive transmission gear 19 for meshing or releasing the meshing.

According to the fifth aspect of the present invention,
When removing the replacement unit from the image forming apparatus main body, the replacement unit is moved in a direction perpendicular to the sleeve shaft 20, the sleeve shaft 20 is removed from the bearing portion 10c of the side plate 10, and the swing member 18 is swung to drive the drive gear. 13 is disengaged from the drive transmission gear 19, and the replacement unit is moved in the direction of the sleeve shaft 20 and taken out of the image forming apparatus main body.

When the replacement unit is mounted on the main body of the image forming apparatus, the replacement unit is inserted in the direction of the sleeve shaft 20 and then moved in the direction perpendicular to the sleeve shaft 20 so that the side plate 10
The bearing shaft 10c receives the sleeve shaft 20 and swings the swing member 18 so that the drive gear 13
Mesh.

According to a sixth aspect of the present invention, there is provided an electrophotographic image forming apparatus having at least a developing device as in an embodiment described with reference to FIG.
An exchange unit provided in the image forming apparatus main body so as to be removably attached to and removed from the image forming apparatus main body by inserting and removing the developing sleeve in the direction of the sleeve axis 20 of the developing apparatus;
A side plate 10 having a bearing 10c for receiving the sleeve shaft 20 when the replacement unit is inserted into the device main body and moved in a direction perpendicular to the sleeve shaft 20; A swinging member 18 that swings when the replacement unit is moved in a direction perpendicular to the sleeve shaft 20 in accordance with the attachment and removal of the replacement unit, and an engagement hole 13a provided at the center of rotation, provided in the apparatus main body. The sleeve shaft 20 of the developing sleeve is inserted into the engagement hole 13a in accordance with the insertion and removal of the replacement unit, and is engaged with the sleeve shaft 20 so as to be able to transmit rotation, or the sleeve shaft 20 is pulled out to engage with the sleeve shaft 20. On the other hand, it is rotatably supported by the rocking member 18 and moves with the rocking of the rocking member 18 to mesh with the drive transmission gear 19 or release the mesh. The drive gear 13, provided with a, characterized in that.

In the invention according to claim 6,
When removing the replacement unit from the image forming apparatus main body, the replacement unit is moved in a direction perpendicular to the sleeve shaft 20, the sleeve shaft 20 is removed from the bearing portion 10c of the side plate 10, and the rocking member 18 is rocked to transmit the drive. The engagement of the drive gear 13 with the gear 19 is released, and the replacement unit is moved in the direction of the sleeve shaft 20 and taken out of the image forming apparatus main body.

Conversely, when the replacement unit is mounted on the image forming apparatus main body, the replacement unit is inserted in the direction of the sleeve shaft 20, the sleeve shaft 20 is inserted into the engagement hole 13 a of the drive gear 13, and After being engaged with the sleeve shaft 20 so as to be able to transmit the rotation, the sleeve 20 moves in a direction perpendicular to the sleeve shaft 20, receives the sleeve shaft 20 by the bearing portion 10 c of the side plate 10, and swings the swing member 18 to drive the drive transmission gear 19.
And the driving gear 13 is meshed.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. First, in the electrophotographic image forming apparatus according to the present invention, although not shown, a drum-shaped or belt-shaped image carrier is provided in the apparatus main body, and a charging device, an optical writing device, and a developing device are provided around the image carrier. A transfer device, a cleaning device, a static elimination device, etc. are provided.

With the rotation of the image carrier, the surface thereof is first uniformly charged by a charging device, and then is written on the image carrier by irradiating, for example, a laser beam with an optical writing device, whereby the image carrier is electrostatically charged. Form a latent image. Subsequently, toner is attached to the latent image portion with a developing sleeve provided in the developing device,
The electrostatic latent image is visualized to form an image on the image carrier.

On the other hand, a recording medium such as a sheet or a card is fed toward the image carrier at a timing synchronized with the rotation of the image carrier. Then, the image on the image carrier is transferred to the recording medium using the transfer device at the transfer position. After the image is transferred to the recording medium, the transferred image is fixed by a fixing device, and then discharged outside the apparatus main body and stacked on a sheet discharge stack unit.

After the image is transferred, the image carrier is rotated,
After removing the residual toner on the surface with the cleaning device,
The surface is neutralized by a static eliminator to prepare for another image formation.

By the way, in the electrophotographic image forming apparatus according to the present invention, for convenience in maintenance, etc., at least a developing device is provided among a charging device, a developing device, a transfer device, a cleaning device, a charge removing device, and the like, and an exchange unit is provided. The developing sleeve is provided so that it can be inserted into and removed from the developing sleeve in the axial direction of the developing sleeve, and can be attached to and removed from the apparatus main body.

According to the first aspect of the present invention, FIG.
As shown in FIG. 2, a side plate 10 made of sheet metal is provided in the back of the image forming apparatus main body. The supporting member 11 made of polyacetal is attached to the outer surface of the side plate 10 by fitting it into the clearance hole 10a and positioning it and then screwing it. The support member 11 has a bearing 12 therein concentrically with the escape hole 10a.
And a semi-cylindrical gear receiver 11a is provided.

Then, the drive gear 13 is housed in the gear receiver 11a. The drive gear 13 is a helical gear, and has an engagement hole 13a that is a square hole at the center of rotation.

On the other hand, a lever member 14 made of resin is attached to one end of the gear receiver 11a by a screw 15 at its base end, and is provided to be rotatable in the front-rear direction around the screw 15. The tip of the lever member 14 is provided with an upwardly directed top cam surface 14a whose distance from the screw 15 gradually decreases toward the front side, and a projection 14b which projects forward and enters the inside through the window hole 10b of the side plate 10. Then, it is normally urged forward by an urging member (not shown).

A fixed shaft 16 is set up on the outer surface of the side plate 10. A first drive transmission gear 17 is provided so as to be rotatable about the fixed shaft 16, and a swing member 18 is provided so as to be swingable so that the tip is placed on the top cam surface 14a.

The oscillating member 18 includes the first drive transmission gear 17
And rotatably supports the second drive transmission gear 19, and is provided with an extension 18a.
a to prevent the drive gear 13 from dropping out of the gear receiver 11a. An elongated hole 18b is provided in the extension 18a,
The central projection 13b of the drive gear 13 is fitted into the elongated hole 18b, and the movement of the drive gear 13 is guided by the elongated hole 18b.

The first drive transmission gear 17 and the second drive transmission gear 17
Are the same helical gears as the drive gear 13.

When the replacement unit is to be mounted on the image forming apparatus main body, the replacement unit is inserted in the direction of the sleeve axis 20 of the developing sleeve provided in the developing device from the front of the apparatus main body with the front cover opened. The square shaft portion 20a at the tip is inserted into the clearance hole 10a of the side plate 10, inserted into the engagement hole 13a of the drive gear 13 through the bearing 12, and engaged with the sleeve shaft 20 so that rotation can be transmitted from the drive gear 13 to the sleeve shaft 20. At the same time, the bearing 12 receives the sleeve shaft 20.

By the way, at the entrance of the engagement hole 13a of the drive gear 13, for example, a guide surface 13 as shown in FIGS.
Form c. Then, the guide surface 13 c is pushed by the tip of the sleeve shaft 20 to rotate the drive gear 13, and the engagement hole 13
a into the engagement hole 13a.
Can be inserted into the sleeve shaft 20.

With the insertion of the sleeve shaft 20 into the engagement hole 13a, the front end side of the unit case of the replacement unit presses the projection 14b, and the lever member 14 rotates rearward against the urging force. Then, the tip of the swinging member 18 riding on the top cam surface 14a is lowered, and the second drive transmission gear 19 is engaged with the drive gear 13 into which the sleeve shaft 20 is inserted.

Accordingly, when the image forming apparatus main body is driven,
The driving force from a motor (not shown) is
Then, the toner is transmitted to the drive gear 13 via the second drive transmission gear 19, the sleeve shaft 20 is rotated to rotate the developing sleeve, and the toner is attached to develop the electrostatic latent image on the image carrier.

At this time, according to the second aspect of the invention, the drive gear 13 is a helical gear and the second drive transmission gear 19
The second drive transmission gear 19 pushes the drive gear 13 in the direction of the sleeve shaft 20 along with the rotation of the
To determine the position in the thrust direction.

Conversely, when removing the replacement unit from the image forming apparatus main body, the front cover of the apparatus main body is opened, the replacement unit is moved in the direction of the sleeve shaft 20 and pulled out to the front side, and the engagement hole 13a of the drive gear 13 is formed. , The sleeve shaft 20 of the developing sleeve is pulled out to release their engagement. At the same time, it is pulled out from the bearing 12.

Then, the lever member 14 pivots toward the front side based on the urging force, pushes up the tip of the swing member 18 by the top cam surface 14a, moves the second drive transmission gear 19, and moves the second drive transmission gear 19 to the drive gear 13. The engagement of the second drive transmission gear 19 is released.

The drive gear 13 from which the sleeve shaft 20 has been pulled out is received by the gear receiver 11a of the support member 11.
As shown in FIG. 5, the support may be received by two support shafts 22 erected on the side plate 10.

In the above-described example, the engaging hole 13a of the drive gear 13 is a square hole, the square shaft portion 20a is formed at the tip of the sleeve shaft 20, and the square shaft portion 20a is inserted into the engaging hole 13a. The rotation can be transmitted from the drive gear 13 to the sleeve shaft 20. However, the outer circumferential projection of the sleeve shaft 20 is engaged with the engagement hole 13.
The rotation of the drive gear 13 may be transmitted to the sleeve shaft 20 by other engagement, such as by engaging with the inner peripheral concave portion of FIG.

Next, according to the third aspect of the present invention, as shown in FIG. 6, the support bracket 30 is attached to the outer surface of the side plate 10. The support bracket 30 has a support shaft 3 facing inward.
The drive shaft 13 is rotatably supported by the support shaft 31. A drive transmission gear 19 meshes with the drive gear 13. The drive transmission gear 19 is provided on the support shaft 3 erected on the side plate 10.
In 2 it is supported rotatably about it.

The drive gear 13 has an annular groove formed between the center of rotation and the outer peripheral teeth to form an engaging portion 13d. Engaging part 1
A plurality of radial locking surfaces 13e are provided in 3d. Then, the engaging portion 13d faces the escape hole 10a of the side plate 10.

By the way, also in the invention according to the third aspect, at least the developing device is provided in the exchange unit. And a sleeve shaft 2 of a developing sleeve provided in the developing device.
At the leading end, an engagement member 33 that rotates together with the sleeve shaft 20 is provided. The engaging member 33 is formed with a claw 33a. The engaging member 33 may be formed integrally with the sleeve shaft 20 using the same material.

When the replacement unit is mounted on the image forming apparatus main body, the replacement unit is inserted in the direction of the sleeve shaft 20 from the front of the apparatus main body with the front cover opened, and the engaging member 33 is inserted through the escape hole 10a of the side plate 10. The sleeve shaft 20 is inserted into the engagement portion 13 d of the drive gear 13, and is supported by the support shaft 31 via the drive gear 13.

Thus, when the image forming apparatus main body is driven,
A driving force from a motor (not shown) is transmitted to the driving gear 13 via the driving transmission gear 19, and a locking surface 13 e is engaged with the pawl 33 a to transmit the rotation of the driving gear 13 to the sleeve shaft 20.
The developing sleeve is rotated to develop the latent image on the image carrier.

According to the fourth aspect of the present invention, as in the embodiment shown in FIG. 6, the drive gear 13 is supported by the support shaft 31 as a helical gear and is slidably provided in the direction of the sleeve shaft 20. When the image forming apparatus main body is driven, the drive gear 13 is moved in the direction of the sleeve shaft 20 on the support shaft 31 by receiving a force from the rotation of the drive transmission gear 19 in contact with the flange 31 a of the support shaft 31, Engaging member 3
3 so that the engaging portion 13d of the drive gear 13 does not come off.

Conversely, when removing the replacement unit from the image forming apparatus main body, the front cover of the apparatus main body is opened, the replacement unit is moved in the direction of the sleeve shaft 20, and the drive gear 1 is moved.
The engagement of the engagement member 33 with the third engagement portion 13d is released and taken out from the apparatus main body.

Subsequently, in the invention according to claim 5, FIG.
As shown in (1), a bearing portion 10c is provided continuously to the large escape hole 10a of the side plate 10.

Further, similarly to the first aspect of the present invention, a fixed shaft 16 is provided on the outer surface of the side plate 10, and the fixed shaft 16
The first drive transmission gear 17 is provided so as to be rotatable around the center, and a swing member 18 is provided so as to be swingable so that the tip is mounted on the outer periphery of the eccentric disk cam 40. The swing member 18 meshes with the first drive transmission gear 17 to rotatably support the second drive transmission gear 19.

Before the replacement unit is mounted, the drive transmission gear 19 is supported while being shifted from the escape hole 10a.
The eccentric disk cam 40 is rotatably attached to the outer surface of the side plate 10. Then, the projection 40 extending from the disc cam 40
a is extended toward the front through the window hole 10 d of the side plate 10. A driven gear 41 is further rotatably attached to the outer surface of the side plate 10.

By the way, also in the invention according to the fifth aspect, at least the developing device is provided in the exchange unit. However, in the invention according to the fifth aspect, the drive gear 13 is fixed to the end of the sleeve shaft 20 of the developing sleeve provided in the developing device.

When the replacement unit is to be mounted on the image forming apparatus main body, the replacement unit is inserted in the direction of the sleeve shaft 20 from the front of the apparatus main body with the front cover opened, and the drive gear is guided by the guide in the apparatus main body. 13 is located outside the side plate 10 through the large escape hole 10a.

Thereafter, as the replacement unit is moved in a direction perpendicular to the sleeve shaft 20, the sleeve shaft 20 is placed on the hole edge of the relief hole 10a, and the sleeve shaft 20 is put into the bearing portion 10c while guiding the sleeve shaft 20 at the hole edge. Position. Then, the drive gear 13 meshes with the driven gear 41 as shown in FIG. Also, the unit case of the replacement unit pushes the projection 40a and rotates the disc cam 40 against the urging force,
The tip of the oscillating member 18 is lowered to move the second drive transmission gear 19
With the drive gear 13.

On the other hand, when removing the replacement unit from the image forming apparatus main body, the front cover of the apparatus main body is opened, the replacement unit is moved in a direction perpendicular to the sleeve shaft 20, and the engagement with the driven gear 41 is released, and the side plate is removed. The sleeve shaft 20 is detached from the bearing portion 10c. At the same time, the disc cam 40 is rotated based on the urging force, and the swing member 18 is swung to release the engagement of the drive transmission gear 19 with the drive gear 13. Thereafter, the replacement unit is moved in the direction of the sleeve shaft 20 and taken out of the image forming apparatus main body.

In FIG. 8, reference numeral 42 denotes a developing sleeve, and reference numeral 43 denotes a drum-shaped image carrier.

Now, in the example shown in FIG. 9, FIGS.
Is slightly modified from the configuration shown in FIG. 1, a band-shaped portion 10e is provided on the side plate 10, and the band-shaped portion 10e is projected outward.
An elongated bearing hole 10f is provided in a portion parallel to the side plate surface.
Open.

Then, when the replacement unit is inserted into the apparatus main body, the sleeve shaft 20 is inserted into the bearing hole 10f, and when the sleeve shaft 20 is moved along the bearing hole 10f in a direction perpendicular to the sleeve shaft 20, the cutting under the band-shaped portion 10e is performed. 7 and 8 engages with the driven gear 41 shown in FIG. 7 and FIG. 8, and the unit case pushes the projection 40a to rotate the disc cam 40 against the urging force, and swings the swing member 18 to cause the second case to swing. The drive transmission gear 19 is moved and meshes with the drive gear 13 through the notch 10h on the belt-shaped portion 10e.

On the other hand, when removing the replacement unit from the image forming apparatus main body, the replacement unit is moved in a direction perpendicular to the sleeve shaft 20 along the bearing hole 10f, and the driven gear 4 is moved.
1 and the disk cam 40 is rotated based on the urging force, and the swing member 18 is swung to drive the drive gear 13.
Is disengaged from the drive transmission gear 19. Thereafter, the replacement unit is moved in the direction of the sleeve shaft 20 and taken out of the image forming apparatus main body.

Finally, according to the invention of claim 6, for example, as shown in FIG.
a, and a bearing portion 10c is provided continuously with the escape hole 10a. Then, a support shaft 16 is set up on the outer surface, the drive shaft 19 is rotatably supported by the support shaft 16, and the swing member 18 is swingably supported.

The swing member 18 has a slot 1 at a position facing the swing member 18.
Open 8c. The drive gear 1 is provided in these long holes 18c.
3 central projections 13b enter. Central projection 13 on the near side
b engages with the hole edge burring portion of the escape hole 10a.
Similarly to the first aspect of the present invention, an engagement hole 13a, which is a square hole, is formed in the center of the drive gear 13.

When the replacement unit is to be mounted on the main body of the image forming apparatus, the replacement unit is inserted in the direction of the sleeve shaft 20 from the front of the main body with the front cover opened, and the sleeve shaft 20 is driven through the escape hole 10a. Gear 1
3 and is engaged with the drive gear 13 so as to be able to transmit rotation from the drive gear 13 to the sleeve shaft 20.

Thereafter, the replacement unit is moved in a direction perpendicular to the sleeve shaft 20 while oscillating the oscillating member 18, and the engagement of the center projection 13b with the hole burring portion of the center projection 13b is released. The sleeve shaft 20 is securely positioned by the engagement with the ten bearing portions 10c. At the same time, the driving gear 13 is guided by the escape hole 10a.
Is moved downward along the long hole 18c, and the drive transmission gear 1 is moved.
Engage with 9.

Thus, when the image forming apparatus main body is driven,
A driving force from a motor (not shown) is transmitted to the driving gear 13 via a driving transmission gear 19, the sleeve shaft 20 is rotated to rotate the developing sleeve, and toner is attached to form an electrostatic latent image on the image carrier. develop.

On the other hand, when removing the replacement unit from the image forming apparatus main body, the front cover of the apparatus main body is opened, and while the swinging member 20 is rocked, the replacement unit is evacuated to the escape hole 10a.
Moves in a direction perpendicular to the sleeve shaft 20 along the side plate 1.
The sleeve shaft 20 is removed from the 0 bearing portion 10c. at the same time,
The drive gear 1 is guided along the escape hole 10a along the long hole 18c.
3 is moved upward, and the engagement of the drive gear 13 with the drive transmission gear 19 is released. Thereafter, the replacement unit is moved in the direction of the sleeve shaft 20 and taken out of the image forming apparatus main body.

[0070]

As described above, claims 1 and 6
According to the invention described in the above, the sleeve shaft of the replacement unit is inserted and engaged with the engagement hole provided at the rotation center of the drive gear,
According to the third aspect of the present invention, the engaging member provided at the tip of the sleeve shaft of the replacement unit is engaged with the engaging portion provided between the rotation center of the drive gear and the outer peripheral tooth portion. According to the invention, the drive gear provided on the sleeve shaft of the replacement unit is directly meshed with the drive transmission gear provided on the image forming apparatus main body side.

Accordingly, the coupling member is not required, the number of parts is reduced, the cost is reduced, and the driving force of the image forming apparatus main body can be transmitted to the replacement unit without increasing the size of the apparatus main body. In addition, the number of components provided in the replacement unit can be reduced, and the replacement unit, which is a consumable product, can be made inexpensive to reduce maintenance costs.

According to the second aspect of the present invention,
When the image forming apparatus main body is driven, the drive gear is moved in the axial direction of the sleeve by receiving the force from the rotation of the drive transmission gear, and the drive gear can be positioned in the thrust direction by hitting the bearing.

According to the fourth aspect of the present invention, in addition to the above,
When the image forming apparatus is driven, the drive gear is moved in the axial direction of the sleeve by receiving a force from the rotation of the drive transmission gear, so that the engagement portion of the drive gear does not come off from the engagement member.

[Brief description of the drawings]

FIG. 1 is a partial perspective view of an electrophotographic image forming apparatus according to the first and second aspects of the present invention, showing a part of the inside of the apparatus main body before a replacement unit is attached, as viewed from the back side.

FIG. 2 is a cross-sectional view taken along a plane connecting the center lines of the drive gear and the drive transmission gear.

FIG. 3 is a perspective view showing a state where a square shaft portion of a sleeve shaft is inserted into an engagement hole of the drive gear.

FIG. 4 is a front view showing another example of the guide surface formed at the entrance of the engagement hole of the drive gear.

FIG. 5 is an explanatory view showing another example of the drive gear support structure.

FIG. 6 is a sectional view similar to FIG. 2, showing an electrophotographic image forming apparatus according to the third and fourth aspects of the present invention.

FIG. 7 is a partial perspective view showing the electrophotographic image forming apparatus according to the fifth aspect of the present invention and showing a part of the inside of the apparatus main body before the replacement unit is attached, as viewed from the back side.

FIG. 8 is a schematic front view after the replacement unit is attached.

FIG. 9 is a partial perspective view of a side plate provided in the apparatus main body for explaining another example of the electrophotographic image forming apparatus according to the invention of claim 5;

FIG. 10 is a partial perspective view showing the electrophotographic image forming apparatus according to the invention as set forth in claim 6, wherein a part of the inside of the apparatus main body before the replacement unit is attached is viewed from the back side.

FIG. 11 is a perspective view illustrating the attachment of a replacement unit in a conventional electrophotographic image forming apparatus.

FIG. 12 is a perspective view illustrating attachment of a replacement unit in another conventional electrophotographic image forming apparatus.

[Explanation of symbols]

 Reference Signs List 10 side plate 10c bearing portion 12 bearing 13 drive gear 13a engagement hole 13d engagement portion 14 lever member 18 swing member 19 drive transmission gear 20 sleeve shaft 20a square shaft portion 31 support shaft 33 engaging member 40 eccentric disk cam 42 development Sleeve 43 Image carrier

Claims (6)

[Claims] An exchange unit which has at least a developing device and which is inserted into and removed from an image forming apparatus main body in a sleeve axial direction of a developing sleeve provided in the developing device; A bearing for receiving the sleeve shaft when the unit is mounted; and a bearing provided in the apparatus main body, having an engagement hole at the center of rotation, wherein the sleeve of the developing sleeve is provided in the engagement hole in accordance with insertion and removal of the replacement unit. A drive gear that inserts a shaft and engages with the sleeve shaft so that rotation can be transmitted, or that pulls out the sleeve shaft to release the engagement, and a drive gear that is provided in the apparatus main body and swings in and out of the exchange unit. A swinging member that moves, and rotatably supported by the swinging member, and moves with the swinging of the swinging member to mesh with the drive gear or release the meshing. That driving with the transmission gear, consisting comprise, electrophotographic image forming apparatus. 2. The drive gear is a helical gear, and is moved in the axial direction of the sleeve by receiving a force accompanying rotation of the drive transmission gear, and is positioned in the thrust direction against the bearing. 2. The electrophotographic image forming apparatus according to 1. 3. An exchange unit having at least a developing device, which is inserted into and removed from a developing sleeve provided in the developing device in a sleeve axial direction and is attached to and removed from the image forming apparatus main body. An engaging member provided on the body and rotating together with the sleeve shaft; rotatably supported in the apparatus main body; having an engaging portion between a center of rotation and an outer peripheral tooth portion; An electrophotographic image forming apparatus, comprising: a drive gear that engages with the sleeve shaft so as to be able to transmit rotation and releases the engagement according to insertion and extraction of the sleeve. 4. The electrophotographic image forming apparatus according to claim 3, wherein said drive gear is supported by a support shaft as a helical gear and is slidably provided in said sleeve axial direction. 5. An exchange unit having at least a developing device, which is inserted and removed in a sleeve axial direction of a developing sleeve provided in the developing device, and which is attached to and removed from an image forming apparatus main body, and fixed to a sleeve shaft of the exchange unit. A drive gear, a side plate provided in the device main body, and having a bearing for receiving the sleeve shaft when the replacement unit is inserted into the device main body and moved in a direction perpendicular to the sleeve shaft; A swinging member that swings when the replacement unit is moved in a direction perpendicular to the sleeve axis in response to the mounting and removal of the replacement unit; and a rotatably supported by the swinging member. A drive transmission gear that moves with the rocking of the member and meshes with or releases the mesh with the drive gear. Apparatus. 6. An exchange unit having at least a developing device, which is provided in the image forming apparatus main body so that it can be inserted and removed in a sleeve axial direction of a developing sleeve provided in the developing device, and which is provided in the image forming apparatus main body. When the replacement unit is inserted into the main body and moves in a direction perpendicular to the sleeve shaft, a side plate having a bearing portion for receiving the sleeve shaft, and provided in the apparatus main body, A swinging member that swings when the replacement unit is moved in a direction perpendicular to the sleeve axis; a swinging member provided in the apparatus main body, having an engagement hole at a rotation center, The sleeve shaft of the developing sleeve is inserted into and removed from the developing shaft to engage with the sleeve shaft so that rotation can be transmitted, or the sleeve shaft is pulled out to release the engagement. A driving gear rotatably supported by the swinging member and moving with the swinging movement of the swinging member to mesh with or release the meshing of the drive transmission gear. Forming equipment.