JPH04240870A - Drive transmission device for color image forming device - Google Patents

Abstract

PURPOSE:To facilitate cutting off and connecting of the drive transmission with only attaching/detaching motion of a cartridge without requiring a special mechanism for evading the drive transmission mechanism on the image forming device main body side when the cartridge is attached. CONSTITUTION:When the cartridge is attached to the image forming device main body, since the driving shaft joint members 2 and 5 are rotated to a phase where they can be connected to each other by rotation members 6 and 3 interlocked with the attachment motion of the cartridge, the driving source on the main body side and the driving shafts of the developing unit are connected with each other with the attachment motion of the cartridge, and transmission of the driving force can be carried out from the driving source to the developing unit. Furthermore, when the cartridge is extracted from the image forming device main body, because the connection of the two driving shafts joint members 2 and 5 are released, the cartridge can be easily extracted from the main body.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive transmission device for a color image forming apparatus such as a color copying machine or a color printer that employs an electrophotographic method.

0002

2. Description of the Related Art Conventionally, at least a developing unit is made into a cartridge that is detachable from the main body of an image forming apparatus, and by replacing the cartridge, it is possible to simplify toner replenishment work, and at the same time, it is possible to remove toner from the clothes and hands of the operator. Prevention of such contamination has been proposed and implemented in monochrome image forming apparatuses having monochrome development units.

[0003] Recently, even in full-color image forming apparatuses having developing units for a plurality of colors, various proposals have been made to incorporate developing units into cartridges.

0004

However, in the full-color image forming apparatus shown in FIG. 5, in order to develop a specific color, it is necessary to selectively drive the developing units 8y, 8m, 8c, and 8bk. For this purpose, the image forming apparatus main body and each developing unit 8y, 8m in the cartridge C,
Either connect the drive shafts of 8c and 8bk and selectively transmit the driving force to the drive shafts, or connect the image forming apparatus main body and the cartridge C with one drive shaft, and connect each drive shaft in the cartridge C. It was necessary to selectively drive the developing units 8y, 8m, 8c, and 8bk.

An example of the former driving method is shown in FIG.
In this system, the drive shaft 9 of each developing unit 8 is selectively connected via joints 91 and 92 to an output shaft 72 of a drive transmission mechanism 71, which is a drive source provided on the image forming apparatus main body side. As shown in FIG. 7, the joints 91 and 92 have pins 91a and 9.
Two protruding portions 2a are provided facing each other, as shown in Fig. 7(c).
By engaging the pins 91a and 92a with each other as shown in FIG.
The signal is transmitted to the drive shaft 9, and the drive shaft 9 is driven to rotate.

In this method, when removing the cartridge C from the main body of the apparatus, the developing unit 8 is removed as shown in FIG.
When the joint 91 (pin 91a) is moved in the direction of the arrow a in FIG.
Since the engagement of the (pin 91a) with the joint 92 (pin 92a) is released, the cartridge can be easily removed from the apparatus main body.

However, when the cartridge C is installed in the main body of the apparatus, each pin 91a of the joints 91, 92
, 92a are in phase as shown in FIGS. 5(a) and 5(b), the pins 91a and 92a interfere with each other, causing
, 92 cannot be connected. Therefore, when installing the cartridge C, as shown in FIG.
0, it was necessary to retreat the drive transmission mechanism 71 to a position where it does not interfere with the joint 91.

Further, when a joint having a shape other than the joints 91 and 92 shown in FIG. 7 is employed, the drive transmission mechanism must be retracted even when the cartridge is removed.

As a modification of this method, it is conceivable to control the drive of the cartridge so that it is always stopped at a phase in which the joint can be connected and disconnected; however, in the event of a jam such as a paper jam, This method was not effective because the drive of the cartridge would stop regardless of the phase of the joint.

In yet another embodiment of this system, as shown in FIG.
2, but in this case, problems such as tooth skipping may occur unless the positional accuracy of the gears 111 and 112 is maintained high.

On the other hand, as an example of the latter drive method (a method in which the main body of the image forming apparatus and the cartridge are connected by one drive shaft and each developing unit is selectively driven within the cartridge), It is conceivable to provide a developing unit drive switching member such as a cam in the cartridge, but in this case, the structure of the cartridge becomes complicated and the number of parts increases, resulting in an increase in the cost of the cartridge.

It is conceivable that the cartridge C can be attached and detached as shown in FIG. photosensitive drum 121
Since the transfer drum 122 and the photosensitive drum 121 are close to each other, there is a risk that the surfaces of the photosensitive drum 121 and the transfer drum 122 will be damaged if such attachment and detachment is performed.

The present invention has been made in view of the above-mentioned problems, and its object is to eliminate the need for a special mechanism for retracting the drive transmission mechanism on the main body of the image forming apparatus when a cartridge is attached or detached. Another object of the present invention is to provide a drive transmission device for a color image forming apparatus in which drive transmission can be easily connected and disconnected simply by attaching and detaching a cartridge.

[0014]

Means for Solving the Problems In order to achieve the above object, the present invention has a cartridge configured to include at least a plurality of developing units, and a drive source for driving each developing unit in the cartridge. In a drive transmission device provided in a color image forming apparatus, the drive transmission device is provided on the apparatus main body side and the cartridge is attached to and removed from the apparatus main body at right angles to the drive shaft of the developing unit. The cartridge and the image forming apparatus are provided with drive shaft coupling members that are freely disconnected from each other when the cartridge is removed, and a rotating member that rotates the drive shaft coupling members to a phase in which the drive shaft coupling members can be coupled to each other by the mounting operation of the cartridge. Its feature is that it is installed on the main body.

[0015]

[Operation] According to the present invention, when the cartridge is installed in the main body of the image forming apparatus, the rotating member rotates the drive shaft coupling members to a phase in which they can be connected to each other in conjunction with the cartridge installation operation, so that image forming is possible. There is no need for a special mechanism for retracting the drive transmission mechanism on the device main body side, and the drive shafts of the drive source and the developing unit are connected by simply installing the cartridge, and the driving force is transmitted from the drive source to the developing unit. becomes possible.

Further, when the cartridge is taken out from the main body of the image forming apparatus, the connection between both drive shaft coupling members is easily released, so that the cartridge can be taken out easily.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a plan view of a drive transmission device according to a first embodiment of the present invention, FIG. 2 is a detailed view of a drive shaft coupling member, and FIG.
FIGS. 8A and 7B are explanatory diagrams showing the state of drive shaft connection.

The cartridge 1 includes a plurality of color developing units, and is attached to and detached from a main body of an image forming apparatus (not shown). A drive shaft 11 that drives a developing sleeve, a toner supply roller, a toner conveying member, etc. is connected to a developing unit (not shown) carried by the cartridge 1.
extends rotatably, and a cartridge-side drive shaft coupling member 2 is supported at the tip of the drive shaft 11 . or,
A drive transmission mechanism 7 incorporating a motor, a gear train, etc. for driving the cartridge 1 is attached to the side plate 4 of the main body of the image forming apparatus.
A main body side drive shaft coupling member 5 is supported at the tip of 2.

By the way, as shown in FIG. 2, the drive shaft coupling member 2 on the side of the cartridge 1 has two protruding pins 21 facing each other for transmitting driving force. They are arranged around the drive shaft 12 with an interval (d+α) slightly wider than the diameter d. Furthermore, tooth profiles 22 are partially formed on the outer periphery of the drive shaft coupling member 2. The drive shaft coupling member 5 on the main body side is also constructed in the same manner as the drive shaft coupling member 2 on the cartridge 1 side, and as shown in FIG. As shown in FIG. 3(b), the pin 21 of the drive shaft coupling member 2 is arranged with a phase shift of 90°.

On the other hand, the cartridge 1 and the main body side plate 4 are provided with rotating members 6 and 3 for rotating the drive shaft coupling members 2 and 5, respectively.
3 are formed with racks 61 and 31 that mesh with the tooth profiles 22 and 52 of the drive shaft coupling members 2 and 5, respectively. Although FIG. 1 shows one developing unit, in reality there are as many developing units as there are colors, and the cartridges are constructed by overlapping them, so the members described above are shown in the front of the drawing. Or they exist so as to overlap in the back direction.

As shown in FIG. 3(a), when the cartridge 1 is inserted into the main body in the direction of arrow c, the drive shaft coupling member 2 and the rotating member 3 on the side of the cartridge 1 are inserted into the main body. The tooth profile 22 of the drive shaft coupling member 2 moves in the same direction with respect to the drive shaft coupling member 5 and the rotation member 6 on the side, and the tooth profile 22 of the drive shaft coupling member 2 moves in the same direction with respect to the rotation member 6.
At the same time, the rack 31 of the rotating member 3 meshes with the tooth profile 52 of the drive shaft coupling member 5. Then, as the cartridge 1 is inserted, the respective drive shaft coupling members 2, 5 are rotated until the tooth profiles 22, 52 partially formed thereon finish meshing with the racks 61, 31 of the rotating members 6, 3. As shown in FIG. 3(b), the pins 21 and 51 stop with a phase shift of 90° from each other. When the cartridge 1 is inserted to a predetermined position while this state is maintained, the pins 21 and 51 can be engaged, and the drive shaft coupling members 2 and 5 can be connected, and the drive transmission mechanism 7 is driven. The force can be transmitted to the drive shaft 11 on the cartridge 1 side. In this way, the driving force can be transmitted from the main body side to the cartridge 1 side simply by the mounting operation of the cartridge 1, without requiring a special evacuation mechanism on the main body side.

Regarding the removal of the cartridge 1, since the pin 21 on the cartridge 1 side slips through the pin 51 on the main body side and the engagement between the drive shaft coupling members 2 and 5 is easily released, the cartridge 1 can be easily removed. It can be taken out.

Next, a second embodiment of the present invention will be explained based on FIG. 4. Note that FIGS. 4(a) and 4(b) are explanatory diagrams showing the state of drive shaft connection, and in this figure, FIGS. 3(a) and (
The same elements as shown in b) are given the same reference numerals, and the description thereof will be omitted below.

In this embodiment, friction members 24 and 5 made of rubber or the like are partially cut out on the outer periphery of the drive shaft coupling members 2 and 5.
4 is attached.

Furthermore, friction members 33 and 63 are attached to the surfaces of the rotating members 3 and 6, respectively.

As shown in FIG. 4(a), when the cartridge 1 is inserted into the main body in the direction of arrow c, the drive shaft coupling member 2 and the rotating member 3 on the side of the cartridge 1 are inserted into the main body. The friction member 24 of the drive shaft joint member 2 abuts the friction member 63 of the rotary member 6, and at the same time the friction member 24 of the drive shaft joint member 2 contacts the friction member 63 of the rotary member 6. The friction member 33 contacts the friction member 54 of the drive shaft coupling member 5. Then, as cartridge 1 is inserted,
Each of the drive shaft coupling members 2, 5 rotates until the friction members 24, 54 partially attached thereto finish contacting the friction members 63, 33 of the rotating members 6, 3, and as shown in FIG. ), the respective pins 21 and 51 stop with a phase shift of 90° from each other. When the cartridge 1 is inserted to the specified position while maintaining this state, the pin 2
1 and 51 can be engaged, and the drive shaft coupling members 2 and 5 can be connected. Therefore, also in this example,
The driving force can be transmitted from the main body side to the cartridge 1 side simply by the mounting operation of the cartridge 1 without requiring a special evacuation mechanism on the main body side.

[0028]

As is clear from the above description, according to the present invention, there is provided a cartridge including at least a plurality of developing units, and a driving source for driving each developing unit in the cartridge. In a drive transmission device provided in a color image forming apparatus, the drive transmission device is provided on the apparatus main body side and the cartridge is attached to and removed from the apparatus main body at right angles to the drive shaft of the developing unit. In addition to providing drive shaft coupling members that are freely disconnected from each other when the cartridge is removed,
A special mechanism is provided for retracting the drive transmission mechanism on the image forming apparatus main body side when the cartridge is attached or detached, since a rotating member is provided that rotates the drive shaft coupling members to a phase in which they can be connected to each other when the cartridge is attached. The advantage is that the drive transmission can be easily connected and disconnected simply by attaching and detaching the cartridge without requiring any additional steps.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a drive transmission device according to a first embodiment of the present invention.

FIG. 2 is a detailed view of the drive shaft coupling member.

FIGS. 3(a) and 3(b) are explanatory diagrams showing the state of drive shaft connection.

FIGS. 4(a) and 4(b) are explanatory diagrams showing the state of drive shaft connection according to a second embodiment of the present invention.

FIG. 5 is a sectional view of main parts of the color image forming apparatus.

FIG. 6 is a plan view of a conventional drive transmission device.

FIGS. 7A, 7B, and 7C are explanatory diagrams showing the state of drive shaft connection in a conventional drive transmission device.

FIG. 8 is a plan view of another conventional drive transmission device.

FIG. 9 is a perspective view showing a structure for attaching and detaching the cartridge to the main body of the image forming apparatus.

[Explanation of symbols]

1 Cartridge 2 Drive shaft coupling member 3 Rotating member 5 Drive shaft coupling member 6 Rotating member 7 Drive transmission mechanism (drive source) 11
Drive shaft 12 of the developing unit Drive shaft of the drive source

Claims (1)

[Claims] 1. A cartridge configured to include at least a plurality of developing units, a drive source for driving each developing unit in the cartridge is provided on the apparatus main body side, and the cartridge is connected to the apparatus main body for development. A device installed in a color image forming apparatus that is attached and detached at right angles to the drive shaft of the unit, the drive source and the drive shaft of each developing unit having drives that are freely disconnected from each other when the cartridge is removed. A color image forming apparatus characterized in that a shaft coupling member is provided, and a rotating member is provided on the cartridge and the image forming apparatus main body, respectively, for rotating the drive shaft coupling member to a phase in which the drive shaft coupling member can be connected to each other by the mounting operation of the cartridge. drive transmission device.