JP4285970B2 - Process cartridge and image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention, for example, a copying machine, a printer or a facsimile or an image forming apparatus such as those of the MFP, and detachably attached to the image forming apparatus main body, or unused or spent discrimination Siu Help Roses The present invention relates to a cartridge and an image forming apparatus including the cartridge.
[0002]
[Prior art]
Conventionally, in an image forming apparatus, charging, writing, developing, transferring, cleaning, etc. are repeated to form toner images on an image carrier, and the toner images are sequentially transferred to transfer paper, OHP film, etc. There is an electrophotographic type that records on a transfer material.
[0003]
In this type of image forming apparatus, in many cases, in order to reduce the size of the image forming apparatus main body or to improve maintainability, it is integrated with the image carrier or separately from the image carrier. A charging device, a developing device, a cleaning device, and the like are integrated to constitute a new / old discrimination mechanism such as a process cartridge.
[0004]
Then, the process cartridge is replaced with an unused one periodically or when it is detected that the toner has run out, but when replacing it with an unused one, the used process cartridge is mistakenly replaced. Sometimes it was attached.
[0005]
Therefore, in the conventional image forming apparatus, for example, as shown in FIG. 9, when the process cartridge 101 is not used, the detected member 102 at the illustrated detection position and the input gear 104 that meshes with the gear portion 103 are provided. The image forming apparatus main body is provided with detecting means 105 and main body gear 106. As the detection means 105, for example, a transmissive or reflective optical sensor is used.
[0006]
Then, when the process cartridge 101 is set in the direction of the arrow in the figure with respect to the image forming apparatus main body, as shown in FIG. 10, the detected portion 107 of the detected member 102 at the detection position is detected by the detecting means 105. It is determined that the process cartridge 101 is unused.
[0007]
Further, after the detection by the detecting means 105, the main body gear 106 is rotated in the forward direction p in the figure to rotate the input gear 104, and when the driving force is transmitted from the image forming apparatus main body side to the process cartridge 101 side, The member 102 rotates in the forward direction p, and becomes the non-detection position shown in FIG. Then, even if the process cartridge 101 is set again in the image forming apparatus main body after use, the detected member 102 is in the non-detection position, so that the image forming operation is not performed.
[0008]
[Problems to be solved by the invention]
By the way, as shown in FIG. 12A, a fur brush 109 for applying a lubricant to the belt-like image carrier 100 is connected to the input gear 104 of the process cartridge 101 via a brush gear 108. The fur brush 109 is in contact with the image carrier 100 with the brush tip in a trailing state so that the fur brush 109 can easily rotate in the forward direction.
[0009]
When such a process cartridge 101 is set in the main body of the image forming apparatus from the direction of arrow P, the input gear 104 is mounted while meshing with the main body gear 106 that is stopped, and rotates in the forward direction p. In conjunction with this, the fur brush 109 also rotates in the forward direction p, the brush tip stops in the state shown in the figure, waits for the driving force from the main body gear 106, and applies the lubricant to the image carrier 100. To do.
[0010]
However, the process cartridge 101 may not be set accurately on the image forming apparatus main body. In that case, as shown in FIG. 12B, the process cartridge 101 is detached from the main body of the image forming apparatus in the arrow Q direction. Then, the input gear 104 is rotated in the reverse direction q while being engaged with the stopped main body gear 106 and then separated from the main body gear 106. Accordingly, the fur brush 109 rotates in the reverse direction q. Since the tip of the brush is always in the trailing state when the fur brush 109 rotates in the forward direction p, the tip of the brush becomes inverted when rotated in the reverse direction q.
[0011]
Then, when the input gear 104 is separated from the main body gear 106, the fur brush 109 is rotated in the forward direction p by the restoring force of the brush tip, the input gear 104 is rotated in the forward direction p, and the detection position shown in FIG. The detected member 107 in the position is slightly rotated in the forward direction p. Therefore, when the unused process cartridge 101 is set again and again in the image forming apparatus main body, the detected member 107 gradually rotates in the forward direction p, and finally shifts from the detection means 105 to the non-detection position. When set in the image forming apparatus main body, it may not be determined that it is unused.
[0012]
Accordingly, a first object of the present invention is to accurately determine whether or not the detachable unit is unused.
[0013]
The second object of the present invention is to achieve the first object with a simple configuration.
[0014]
A third object of the present invention is to reliably move the detected member from the detection position to the non-detection position.
[0015]
A fourth object of the present invention is to reliably transmit the rotation of the image forming apparatus main body side to the detachable unit side with a simple configuration.
[0016]
A fifth object of the present invention is to provide an image forming apparatus provided with a detachable unit new / old discriminating mechanism that achieves the above-mentioned objects.
[0017]
[Means for Solving the Problems]
Therefore, the process cartridge of the invention according to claim 1 is to achieve the first object described above.
An image carrier;
When attaching to the image forming apparatus main body, the input gear meshed with the main body gear provided in the apparatus main body in the forward direction, and removed from the apparatus main body, the input gear rotated in the reverse direction;
It is provided coaxially with the input gear, and is engaged with the input gear by providing play with respect to the forward rotation of the input gear, and when the device body is driven, the input is performed by the body gear. A rotation transmitting member that transmits rotation of the input gear after rotating the gear in the forward direction to eliminate the play;
A biasing member that is provided between the input gear and the rotation transmission member and biases in a direction to increase play between them;
A fur brush , which is an actuated member that is actuated by the rotation of the rotation transmitting member being transmitted and contacting the image carrier;
A detected member that is supported movably between a detection position and a non-detection position and is in a detection position when not in use, and the rotation of the rotation transmission member is transmitted to be a non-detection position;
Is provided.
[0018]
The invention according to claim 2, in order to achieve the first object described above, a process cartridge according to claim 1, before Symbol the actuating member, for applying a lubricant to the image bearing member it characterized in that it is a fur brush.
[0022]
According to a third aspect of the present invention, in order to achieve the fifth object described above, the image forming apparatus includes the process cartridge according to the first aspect, and the detected member on the image forming apparatus main body side. It is characterized in that a detecting means for detecting the above is provided.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an overall schematic configuration of an internal mechanism of a color image forming apparatus.
[0024]
Reference numeral 1 in the drawing denotes a belt-shaped image carrier. The image carrier 1 is wound around the rotation rollers 2 and 3 and is conveyed in the direction of arrow A in the figure by the rotational drive of one rotation roller 2.
[0025]
Reference numeral 4 in the figure denotes a charging charger as charging means for uniformly charging the surface of the image carrier 1. Reference numeral LW in the drawing denotes a laser optical device as electrostatic latent image exposure means. Reference numeral 6 in the drawing denotes a rotary color developing device in which four developing units having yellow, magenta, cyan, and black developers are integrally formed.
[0026]
Further, reference numeral 10 in the figure denotes an intermediate transfer belt as an intermediate transfer member. The intermediate transfer belt 10 is wound around the rotation rollers 11 and 12 and is conveyed in the direction of arrow B in the figure by the rotational drive of one rotation roller 11. The intermediate transfer belt 10 is brought into contact with the image carrier 1 by the rotating roller 3. On the intermediate transfer belt 10 side of the contact position, a conductive bias roller 13 is in contact with the back surface of the intermediate transfer belt 10 under predetermined conditions.
[0027]
When an image forming operation is performed in this color image forming apparatus, the image carrier 1 is first uniformly charged by the charging charger 4 and then scanned and exposed by the laser optical device LW based on the image information. An electrostatic latent image is formed on the surface. The image information to be exposed is single-color image information obtained by separating a desired full-color image into yellow, cyan, magenta, and black color information.
[0028]
The formed electrostatic latent image is developed in a single color with predetermined yellow, cyan, magenta, and black toner, respectively, by a rotary color developing device 6 to be described later, and each color image is sequentially formed on the image carrier 1. .
[0029]
Each single-color image formed on the image carrier 1 rotating in the direction of arrow A in the figure is placed on the intermediate transfer belt 10 rotating in the direction of arrow B in the figure in synchronization with the image carrier 1, and yellow, cyan, magenta, In addition, for each single color of black, the images are sequentially superimposed and transferred by a predetermined transfer bias applied to the bias roller 13.
[0030]
The yellow, cyan, magenta, and black images superimposed on the intermediate transfer belt 10 are conveyed from the sheet feeding cassette 17 to the transfer position via the sheet feeding roller 18, the pair of conveying rollers 19A and 19B, and the pair of registration rollers 20A and 20B. The images are transferred onto the transfer paper 17 </ b> A by the transfer roller 14. After the transfer is completed, the transfer sheet 17A fixes the transferred image by the fixing device 80 to complete a full-color image, and is discharged onto the paper discharge stack unit 82 through the paper discharge roller pair 81A and 81B.
[0031]
Reference numeral 15 in the figure denotes a cleaning device that includes a cleaning member 15A that always contacts the image carrier 1 and cleans the toner on the image carrier 1, and reference numeral 15C denotes a waste toner collection container that stores waste toner. is there. Reference numeral 16 in the drawing denotes a cleaning device for the intermediate transfer belt 10. The cleaning blade 16A of the cleaning device 16 is held at a position away from the surface of the intermediate transfer belt 10 during the image forming operation, and the formed image is transferred onto the transfer paper 17A and then applied to the surface of the intermediate transfer belt 10. Touch.
[0032]
The waste toner scraped off from the intermediate transfer belt 10 by the cleaning blade 16A is conveyed toward the front of the drawing by the auger 16B provided in the cleaning device 16, and further provided on the front side of the process cartridge (detachable unit) 22 in the drawing. The toner is transported to the waste toner collecting container 15C by a transport unit in which is omitted. By replacing the process cartridge 22 when a predetermined amount or more of waste toner is accommodated in the waste toner collecting container 15C, the life of the process cartridge 22 is extended.
[0033]
The image carrier 1, the charger 4, the intermediate transfer belt 10, and the cleaning devices 15 and 16 are integrally configured as the process cartridge 22 described above. The case exterior portion of the process cartridge 22 on the registration roller 20B side also has a function as a paper conveyance guide.
[0034]
FIG. 2 shows a case where the process cartridge 22 is replaced in the color image forming apparatus shown in FIG.
[0035]
When the process cartridge 22 is replaced, the lock mechanism (not shown) is released, and the front cover 8 is opened around a support shaft (not shown) as shown in FIG. The front cover 8 includes a pair of conveying rollers 19A and 19B, a pair of registration rollers 20A and 20B, a transfer roller 14, and the like.
[0036]
Then, after rotating the process cartridge 22 about the lower side and standing straight, the process cartridge 22 is lifted upward as indicated by an arrow C in FIG. 3 and taken out from the image forming apparatus main body M.
[0037]
By the way, in the color image forming apparatus of this example, as shown in FIG. 1, a fur brush 30 that contacts the image carrier 1 and applies lubricant to the process cartridge 22 is provided. A brush gear 31 shown in FIG. 4 is fixed to the fur brush (operated member) 30 on the same axis. A unit gear 32 meshes with the brush gear 31, and a filler gear 34 meshes with the unit gear 32 via an intermediate gear 33. The filler gear 34 meshes with the gear portion 36 of the detected member 35 having the fan-shaped gear portion 36 and the non-detecting portion 38.
[0038]
The detected member 35 is rotatably supported at a detection position and a non-detection position, and is in a detection position as shown when the process cartridge 22 is not used.
[0039]
On the other hand, the image forming apparatus main body M is provided with a detection means 40 and a main body gear 41. As the detection means 40, for example, a transmissive or reflective optical sensor or a microswitch is used as in the conventional case.
[0040]
When the process cartridge 22 is inserted as shown by the arrow D in FIG. 3 and is inserted into the image forming apparatus main body M, the state shown in FIG. 5, the detected member 35 comes close to the detection means 40 and the unit gear 32 meshes with the main body gear 41 as shown in FIG. Thereby, the detection part 40 of the detection member 35 in the detection position is detected by the detection means 40, and it is determined that the process cartridge 22 is unused.
[0041]
After detection by the detecting means 40, the image forming apparatus main body M is driven and the main body gear 41 is rotated forward in the direction of the arrow to rotate the unit gear 32, and is driven from the image forming apparatus main body M side to the process cartridge 22 side. Transmit power. Then, the forward rotation of the unit gear 32 is transmitted through the intermediate gear 33 and the filler gear 34 to rotate the detected member 35 forward. Eventually, as shown in FIG. 6, the engagement with the filler gear 34 is disengaged, the detected member 35 is rotated to the non-detection position, the detected portion 38 is disengaged from the detecting means 40, and the process cartridge 22 is then moved to the next position. When set, it is determined that it has been used.
[0042]
When the process cartridge 22 in which the detection member 35 is in the non-detection position is set in the image forming apparatus main body M, the detection member 35 cannot be detected by the detection means 40 from the beginning as shown in FIG. The start of image formation is prohibited, and the fact is displayed on the display unit, for example.
[0043]
In this example, as shown in FIG. 7, the unit gear 32 is divided into an input gear 32A that meshes with the main body gear 41, and a rotation transmission gear (rotation transmission member) 32B that meshes with the intermediate gear 33 and the brush gear 31. Protrusions (engaging portions) a1 and a2 and protrusions (engaging portions) b1 and b2 that engage with each other with play S are provided on the surfaces where the input gear 32A and the rotation transmission gear 32B are opposed to each other, and further fitted. One hole c is provided. The protrusions a1 and a2 and the protrusions b1 and b2 are provided at intervals of 180 degrees on the circumference of the opposing surface of the gear.
[0044]
Then, both ends of a coil spring (biasing member) 42 are inserted and attached to the fitting hole c, the input gear 32A is rotatably provided on a rotation shaft (not shown), and the rotation transmission gear 32B is fixedly provided. With the coil spring 42, the projections a1 and a2 are brought into contact with the projections b1 and b2, and the projections a1 and a2 are attached in the direction of the arrow in FIG. 8 in the direction of increasing the play S between the input gear 32A and the rotation transmission gear 32B. To force.
[0045]
In this example, the attaching / detaching unit new / old discriminating mechanism includes an input gear 32A, a rotation transmission gear 32B, an intermediate gear 33, a filler gear 34, a detected member 35 provided in the process cartridge 22, and a detecting means 40 provided in the image forming apparatus main body M. Is provided.
[0046]
In this way, when the unused process cartridge 22 is attached to the image forming apparatus main body M, the input gear 32A is rotated from the state shown in FIG. 4 to the state shown in FIG. 8, even if the input gear 32A rotates in the direction of the arrow N (forward direction) against the urging force of the coil spring 42 in FIG. Therefore, the protrusions a1 and a2 do not engage with the protrusions b1 and b2. Therefore, since the forward rotation of the input gear 32A is not transmitted to the rotation transmission gear 32B and forward rotated, the detected member 35 is not forward rotated via the intermediate gear 33 and the filler gear 34.
[0047]
Further, when removing the unused process cartridge 22 from the image forming apparatus main body M, the process cartridge 22 is rotated from the state shown in FIG. 5 to the state shown in FIG. Release the input gear 32A. At this time, when the process cartridge 22 is set, the input gear 32A rotates in the direction of arrow R (reverse direction) in FIG. However, since there is a play S between the input gear 32A and the rotation transmission gear 32B, the projections a1 and a2 do not engage with the projections b1 and b2, and the rotation transmission gear 32B does not rotate reversely.
[0048]
In addition, in this example, the coil spring 42 is provided between the input gear 32A and the rotation transmission gear 32B, and the input gear 32A is urged in the direction of the arrow R with respect to the rotation transmission gear 32B. Is always removed from the image forming apparatus main body M, the input gear 32A rotates in the reverse direction R, and the protrusion a1 and the protrusion b1, and the protrusion a2 and the protrusion b2 are engaged, that is, the play S is always maintained. can do. Therefore, even if the unused process cartridge 22 is set in the image forming apparatus main body M many times, the detected portion 38 of the detected member 35 does not always shift from the detection position.
[0049]
When the image forming apparatus is driven, the input gear 32A is rotated in the forward direction N from the main body gear 41 by the driving force of the image forming apparatus main body M. Then, the input gear 32A rotates in the direction in which the play S decreases against the urging force of the coil spring 42, that is, the forward direction N, and eventually the protrusion a1 engages with the protrusion b2 and the protrusion a2 engages with the protrusion b1. . Thereafter, the rotation of the input gear 32A is transmitted and the rotation transmission gear 32B is operated, both rotate together, and the driving force is transmitted to the fur brush 30 via the brush gear 31 to rotate in the forward direction. .
[0050]
On the other hand, when the rotation transmission gear 32B rotates by a certain angle, the member 35 to be detected rotates through the filler gear 34 that meshes with the rotation transmission gear 32B through the intermediate gear 33, and becomes the non-detection position.
[0051]
The intermediate gear 33 and the filler gear 34 may be eliminated, and the input gear 32A may be directly meshed with the detected member 35, or may be meshed via a plurality of intermediate gears instead of one.
[0052]
In the above-described example, the engaging portion is configured by the protrusions a1 and a2 of the input gear 32A and the protrusions b1 and b2 of the rotation transmission gear 32B. However, the present invention is not limited to this, for example, the input The engaging portion may be configured by providing a protrusion on one of the gear 32A and the rotation transmission gear 32B and providing an arc-shaped groove on the other, and fitting the two together.
[0053]
【The invention's effect】
Or as described, the invention according to claim 1, the process cartridge is detachable unit, in a forward direction when mounting to the image forming apparatus main body, the input gear so as to rotate in opposite directions when removed from the image forming apparatus main body A rotation transmission member that engages with play with respect to the forward rotation of the input gear, operates the fur brush as the actuated member by the engagement, and sets the sensed member to the non-detection position. And a biasing member is provided between the rotation transmission member and the input gear to bias the rotation transmission member in the direction of increasing play, so that the process cartridge can be remounted on the image forming apparatus main body many times. and even, without transmitting the rotation of the input gear to the rotation transmitting member, accurately determine the process cartridge is whether the unused and set in the image forming apparatus main body It can be.
[0054]
Further , since the actuated member is a fur brush for contacting the image carrier, the sensed member rotates because the fur brush is not rotated no matter how many times the process cartridge is attached to or detached from the image forming apparatus body. Therefore, it is possible to more accurately determine whether or not the process cartridge set in the image forming apparatus main body is unused.
[0055]
According to the third aspect of the present invention, since the detection member is detected by the detection unit on the image forming apparatus main body side, is the detachable unit unused with a simple configuration without providing the detection unit on the detachable unit side? It is possible to accurately determine whether or not.
[0058]
According to the invention of claim 3 , since the process cartridge according to claim 1 is provided, an image forming apparatus that achieves the effect of claim 1 can be provided.
[Brief description of the drawings]
FIG. 1 is an overall schematic configuration diagram of an internal mechanism of a color image forming apparatus.
FIG. 2 is an explanatory diagram showing a state in which a front cover of the main body of the image forming apparatus is opened to replace a process cartridge in the color image forming apparatus.
FIG. 3 is an explanatory diagram of a process cartridge attached / detached state.
FIG. 4 is a diagram illustrating a state in which the process cartridge is inserted into the image forming apparatus main body.
FIG. 5 is an explanatory diagram illustrating a state in which the image forming apparatus is rotated and set in the image forming apparatus main body after insertion.
FIG. 6 is an explanatory diagram of a state when driving force is transmitted from the image forming apparatus main body side to the process cartridge side after setting.
FIG. 7 is a perspective view showing attachment of an input gear and a rotation transmission gear.
FIG. 8 is a cross-sectional view thereof.
FIG. 9 is an explanatory diagram of a state in which a conventional process cartridge is attached.
FIG. 10 is an explanatory diagram of a set state of the conventional process cartridge.
FIG. 11 is an explanatory diagram of a state when a driving force is transmitted from the image forming apparatus main body side to the process cartridge side.
FIGS. 12A and 12B are explanatory diagrams of a rotation transmission state in the forward direction to the fur brush, and FIG.
[Explanation of symbols]
22 Process cartridge (detachable unit)
30 Fur brush (actuated member)
31 Brush gear 32 Unit gear 32A Input gear 32B Rotation transmission gear (rotation transmission member)
33 Intermediate gear 34 Filler gear 35 Detected member 36 Detected member gear portion 38 Detected member detected portion 40 Detecting means 41 Body gear 42 Coil spring (biasing member)
a1, a2, b1, b2 Protrusion (engagement part)
M Image forming apparatus body N Forward direction R Reverse direction S Play

Claims (3)

An image carrier;
When attached to the image forming apparatus main body, the input gear meshes with the main body gear provided in the apparatus main body in the forward direction, and when removed from the apparatus main body, the input gear is rotated in the reverse direction;
It is provided coaxially with the input gear, is engaged with the input gear by providing play with respect to the forward rotation of the input gear, and when the device main body is driven, the input is performed by the main body gear. A rotation transmitting member that transmits rotation of the input gear after rotating the gear in the forward direction to eliminate the play;
A biasing member that is provided between the input gear and the rotation transmission member and biases in a direction to increase play between them;
A fur brush , which is an actuated member that is actuated by the rotation of the rotation transmitting member being transmitted and contacting the image carrier;
A detected member that is supported movably between a detection position and a non-detection position and is in a detection position when not in use, and the rotation of the rotation transmission member is transmitted to be a non-detection position;
A process cartridge . Wherein the actuating member, characterized in that it is a fur brush for applying a lubricant to the image bearing member, process cartridge according to claim 1. An image forming apparatus comprising: the process cartridge according to claim 1; and a detection unit configured to detect the detected member on the image forming apparatus main body side.

Images