JPH09185254A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device which allows the sharing of the use of a part, such as a process cartridge case, as much as possible and, at the same time, to make a process cartridge non-interchangeable without using an extra means such as a discrimination sensor or an engaging member and engaged member. SOLUTION: As a driven gear 20 which is provided on the process cartridge 8, a helical gear which is different in form between process cartridge types is used. As a driving gear which is provided on the device main body so as to engage with the driven gear, one whose form allows the engagement with only the driven gear 20 of the proper process cartridge 8 is used. When an improper process cartridge 8 is attached to the device main body, the driven gear 20 cannot engage with the driving gear of the device main body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus, and more particularly to an image forming apparatus equipped with a process cartridge type developing device that can be attached to and detached from an apparatus main body.

[0002]

2. Description of the Related Art Conventionally, in an electrophotographic image forming apparatus such as a copying machine, a printer, a facsimile, etc., a photosensitive drum, a charger, a developing device, A process cartridge is used in which a cleaner device and the like are incorporated in a case and integrated, and the process cartridge is detachably attached to the device body. This process cartridge is designed exclusively for each type of image forming apparatus. Also, the process cartridge is handled as a consumable item,
When recording of the set number of sheets is completed or when there is a failure,
It was replaced by a new one by the operator (user).

[0003]

However, when a dedicated process cartridge is designed for each of a plurality of types of image forming apparatuses and each process cartridge is assembled using dedicated components, the types of components are different. There is a drawback that the number of products increases and the manufacturing cost increases.
Therefore, it is desirable to share the parts of the process cartridge for different models as much as possible, and therefore, it is possible to share the case. However, if the process cartridges are assembled by sharing the case, the process cartridges for different image forming apparatuses have the same outer shape, so that a process cartridge for one model can be mounted on another model. Therefore, when a user purchases a process cartridge and replaces it, even if he / she accidentally purchases a process cartridge for another model, he / she can still install it in the image forming apparatus without any trouble. The problem arises that Therefore, in order to share the parts of the process cartridge, it is necessary to make each process cartridge mountable only in the image forming apparatus corresponding to the process cartridge and to provide incompatibility.

It has been conventionally known that parts detachable from the main body of the apparatus have incompatibility, and as a method therefor, a method of using a sensor for compatibility determination or mutual engagement is used. There is known a method of using an engaging member and an engaged member that allow the above (see Japanese Patent Application Laid-Open No. 7-134497). Therefore, it is possible to apply these methods to the process cartridge. However, if a sensor for compatibility discrimination is used, not only an expensive discrimination sensor is required, but also parts for operating the discrimination sensor need to be attached to the process cartridge side, which increases costs. There is a drawback that it causes Further, even in the method using the engaging member and the engaged member, it is necessary to provide the engaging member and the engaged member in the apparatus main body and the process cartridge, respectively, which also causes a disadvantage of increasing cost.

The present invention has been made in view of the above-mentioned problems, and uses the discrimination sensor, or the engaging member and the engaged member while sharing parts such as the case of the process cartridge as much as possible. It is an object of the present invention to provide an image forming apparatus in which a process cartridge has incompatibility without using extra means such as using.

[0006]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention uses, as a driven gear provided in a process cartridge, a helical gear having different specifications depending on the type of the process cartridge. Is a helical gear of a specification that meshes only with the driven gear of an appropriate process cartridge. With this configuration, when the process cartridge is mounted on the main body of the image forming apparatus, if the process cartridge is a proper one for the main body of the image forming apparatus, the driving gear and the driven gear mesh with each other, but when the wrong process cartridge is mounted. Since the driving gear and the driven gear do not mesh with each other, it can be determined that the process cartridge is erroneous, and an extra means such as using a conventional discrimination sensor or using an engaging member and an engaged member is required. You can have incompatibility without using it.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is a photosensitive drum, a charger,
Developing device, cleaner device, case containing these,
In a process cartridge including a driven gear that is connected to the photosensitive drum and meshes with a drive gear provided on the apparatus main body side to transmit rotation, at least the case is made as a common component with other types of process cartridges. However, the driven gear is a hasba gear with specifications different from those of other types of process cartridges, and the drive gear on the device body side is also a hasba gear with specifications that mesh only with the driven gears of the proper process cartridge. The drive gear and the driven gear are properly meshed with each other only when the proper process cartridge is mounted on the main body of the apparatus.

At least the case of the process cartridge constructed as described above is made as a common part that can be used for a plurality of types of process cartridges, and since the outer shape is the same, it is not appropriate for the mounting position of a certain apparatus main body. It is possible to mount the process cartridge, but in that case, the specifications of the driving gear and the driven gear are different, so they cannot engage with each other. Therefore, it is possible to avoid a trouble caused by mounting an improper process cartridge.

[0009]

1 is a schematic cross-sectional view of a facsimile apparatus equipped with an image forming apparatus according to an embodiment of the present invention. 1 is an apparatus main body, 2 is an image forming apparatus for recording received information on recording paper and outputting it. The receiving unit 3 includes a transmitting unit 3 for reading and transmitting a document to be transmitted, and 4 an operation panel.

The receiving unit 2 receives a received paper from a paper feed cassette 6 for setting recording paper, a paper feed roller 7 for feeding the recording paper, a process cartridge 8 having a photosensitive drum 15, and a photosensitive drum 15. Laser scanning unit 10 that scans with a laser beam 9 to form an electrostatic latent image, a transfer roller 11 that is arranged so as to be in contact with the photosensitive drum 15, and that transfers the toner image on the photosensitive drum 15 to recording paper, and recording paper. Further, a fixing unit 12 for fixing the toner image, a receiving tray 13 for accumulating the recorded recording sheets, and the like are provided. The process cartridge 8 is configured to be attachable to and detachable from the apparatus main body 1, and as shown in FIGS. 2 and 3, the photosensitive drum 15 and a charger 16 that uniformly charges the outer peripheral surface of the photosensitive drum 15. And toner container 17a, stirring blade 17
b, a developing roller 17c and the like, and a developing device 1 for applying toner to the electrostatic latent image on the outer peripheral surface of the photosensitive drum 15 to develop the electrostatic latent image.
7, a cleaner device 18 for removing the residual toner on the outer peripheral surface of the photosensitive drum 15, a case 19 containing these,
It is provided with a driven gear 20 and the like which is connected to the photosensitive drum 15 and meshes with a drive gear (not shown) provided on the apparatus main body side to transmit rotation.

The operation of the receiving unit 2 (image forming apparatus) having the above-described structure will be described. Referring to FIGS.
Rotates in the direction indicated by arrow A (see FIG. 3), the surface of the charger is uniformly charged by the charger 16, and the laser scanning unit 10 irradiates the laser beam 9 to form an electrostatic latent image. A toner image 17 is applied to the electrostatic latent image to form a toner image, and a recording paper 21 is supplied at the same timing as the toner image, and the transfer roller 11 applies the toner image to the recording paper 21. Is formed, and then the fixing unit 12 fixes the toner image on the recording paper 21 to form an image.

Here, the process cartridge 8 is assembled in the state shown in FIGS. 2 and 3 in advance, and is handled in a state in which a predetermined amount of toner is sealed in the toner storage portion 17a, and the process cartridge 8 is manufactured. It is incorporated in the apparatus main body 1 at the factory and is also sold as a replacement process cartridge. On the user side, when the process cartridge incorporated in the image forming apparatus is to be replaced (for example, when recording of a preset number of sheets is completed or when it fails), the operator replaces it with a new one. To do.

There are a plurality of types of image forming apparatuses using this type of process cartridge, and naturally there are a plurality of types of process cartridges corresponding to the respective image forming apparatuses. Therefore, in order to reduce the manufacturing cost of these plural kinds of process cartridges, the process cartridge 8 in the present embodiment is designed to share the constituent parts thereof, and at least the case 19 is shared with other kinds of process cartridges. Made as possible shared parts. Therefore, the outer shape of the process cartridge 8 is the same as that of other types, and the process cartridge 8 can be attached to other types of image forming apparatuses. However, if the process cartridge 8 is used by being attached to an image forming apparatus of another model, trouble may occur due to, for example, the density, type, or color of the toner contained in the process cartridge 8. It is necessary to render the image forming apparatus unmountable, that is, incompatible with the image forming apparatus, and in the present invention, this incompatibility is caused by a process with a drive gear (not shown) provided in the apparatus body of the image forming apparatus. This is achieved by utilizing the meshing of the driven gear 20 provided in the cartridge 8. Hereinafter, a configuration in which incompatibility is achieved by meshing gears will be described.

FIG. 4 illustrates this configuration.
(A) shows a state in which the driven gear 20 of the process cartridge 8 meshes with the drive gear 23 provided in the apparatus main body 1, and (b) shows the state in which the apparatus main body 1A of another type of image forming apparatus is provided. The state in which the driven gear 20 of the process cartridge 8 is trying to mesh with the driving gear 23A that is present is shown in (c) of the apparatus body 1A of the image forming apparatus of another model.
The driven gear 20A of the process cartridge 8A, which is suitable for the image forming apparatus, is meshed with the drive gear 23A provided in FIG. FIG. 4 (a)
As is clear from (c), a helical gear is used for both the driven gears 20 and 20A provided on the process cartridges 8 and 8A and the drive gears 23 and 23A provided on the apparatus main bodies 1 and 1A. The driven gears 20 provided on the different types of process cartridges 8 and 8A,
20A has the same diameter, but the twist angles of the teeth are different from α1 and α2, and hence the specifications of the driven gear are different. Further, the drive gears 23 and 23A provided in the apparatus main bodies 1 and 1A of the image forming apparatus corresponding to the process cartridges 8 and 8A are also the corresponding driven gears 20 and 20.
In order to be able to mesh with A, respectively, the twist angles of the teeth are set in the opposite directions of the driven gears 20 and 20A, but equal angles α1 and α2. Therefore, the drive gears 23, 23
A has the same diameter as each other, but has different tooth twist angles.

With this structure, as shown in FIG.
As shown in (c), when the proper process cartridges 8 and 8A are set in the apparatus main bodies 1 and 1A, respectively, the driven gear 2 is set in the driving gears 23 and 23A, respectively.
0 and 20A mesh properly, but as shown in FIG. 4B, when the process cartridge 8 is mistakenly set in the apparatus main body 1A of another model, the driven gear 20 of the process cartridge 8 is twisted. Since the angle α1 is different from the twist angle α2 of the drive gear 23A provided in the apparatus body 1A, they cannot engage with each other, and the process cartridge 8 cannot be properly mounted in the apparatus body 1A. For this reason,
An operator or an assembler can easily determine that the process cartridge 8 is not appropriate for the apparatus main body 1A, and avoids accidentally incorporating and using an incorrect process cartridge.

FIG. 5 is a drawing similar to FIG. 4 showing another embodiment of the present invention. In this embodiment, although the driven gears 20 and 20B provided in the process cartridges 8 and 8B of different types are helical gears having the same diameter,
You are changing the tooth module and therefore the number of teeth is different. Further, the drive gears 23 and 23B respectively provided in the apparatus main bodies 1 and 1B corresponding to the process cartridges 8 and 8B are also designed to be able to mesh only with the corresponding driven gears 20 and 20B, respectively. The tooth modules are different from each other even though the helical gears have the same diameter. Thus, FIG. 5 (a), (c)
As shown in, when proper process cartridges 8 and 8B are set in the apparatus main bodies 1 and 1B, respectively,
The driven gears 20 and 20 are respectively attached to the driving gears 23 and 23B.
5B properly meshes with each other, but as shown in FIG. 5B, when the process cartridge 8 is mistakenly set in the apparatus main body 1B of another model, the driven gear 20 of the process cartridge 8 and the apparatus main body 1B. Since the tooth module is different from that of the drive gear 23B provided in the above, it cannot engage with each other, and an operator or an assembly worker can easily determine that the process cartridge 8 is not appropriate for the apparatus main body 1B, and erroneously. The incorporation and use of improper process cartridges is avoided.

FIG. 6 shows another embodiment of the present invention, which is shown in FIG.
FIG. In this embodiment, the driven gears 20 and 20C respectively provided on the different types of process cartridges 8 and 8C are helical gears having the same diameter, but the teeth are twisted in opposite directions. Further, the apparatus main bodies 1 and 1 corresponding to the process cartridges 8 and 8C, respectively.
The drive gears 23 and 23C respectively provided on C are also designed so that they can be engaged only with the corresponding driven gears 20 and 20C, respectively.
23C has the same diameter, but the twisting directions of the teeth are opposite. Thus, as shown in FIGS. 6A and 6C, when the proper process cartridges 8 and 8C are set in the apparatus main bodies 1 and 1C, respectively, the driven gears 20 and 20C are correctly set in the driving gears 23 and 23C, respectively. Mesh with each other,
As shown in FIG. 6B, when the process cartridge 8 is mistakenly set in the apparatus main body 1C of another model, the drive gear 23 provided in the apparatus main body 1C is set.
Since the twisting directions of C and the driven gear 20 are different, the C and the driven gear 20 cannot mesh with each other, and an operator or an assembly worker can easily determine that the process cartridge 8 is not appropriate for the apparatus main body 1C, and is erroneously inappropriate. It is avoided to incorporate and use a different process cartridge.

In each of the above embodiments, the driven gears 20, 20 provided on the different types of process cartridges are used.
A, 20B, and 20C have the same diameter, but by changing the twist angle of the teeth, the module, the twisting direction, etc., it is possible to mesh only with the drive gear of the corresponding device main body and mesh with the drive gears of other models. Although the specification is not possible, instead of this, by changing the diameter of the helical gear, a configuration may be adopted in which only the drive gear of the corresponding apparatus main body is engaged and the drive gears of other models cannot be engaged.

Further, in the above-described embodiment, the image forming apparatus having the structure in which one process cartridge is attached to the main body of the apparatus is shown, but the present invention is not limited to this structure, and one main body of the apparatus is provided. The present invention can also be applied to an image forming apparatus in which a plurality of process cartridges of different types are mounted. Even in that case, the driven gears of different types of process cartridges have different specifications from each other, and only when the driven gears are mounted in the proper positions of the apparatus main body, the drive gears arranged at the positions are engaged with each other. It is possible to prevent improper mounting of the process cartridge.

[0020]

As is apparent from the above description, according to the present invention, a plurality of types of process cartridges are made as at least the case as a common part, but the driven gears provided in the process cartridges are different for each type of process cartridge. The different specifications of the hasbar gear, and the drive gear on the side of the main body of the device is also the specifications of the specifications that meshes only with the driven gear of the proper process cartridge, so that only when the proper process cartridge is attached to the main body of the device. The driven gear can be meshed with the drive gear of the main body of the apparatus. Therefore, when trying to mount an improper process cartridge, the driven gear does not mesh with the drive gear, so the process cartridge is incorrect. In other words, it is possible to have incompatibility, in other words, the case Manufacturing cost can be reduced by sharing the included parts, and an extra means such as using a discrimination sensor for providing incompatibility as in the past or using an engaging member and an engaged member It is not necessary to use, and the structure of not only the process cartridge but also the apparatus main body is not complicated, and the manufacturing cost can be reduced also from this point.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a facsimile apparatus including an image forming apparatus according to an embodiment of the present invention.

2 is a schematic perspective view of a process cartridge used in the image forming apparatus shown in FIG.

FIG. 3 is a schematic sectional view of the process cartridge shown in FIG.

FIG. 4A is a schematic side view showing a state in which a driven gear of a proper process cartridge is engaged with a drive gear provided in the apparatus main body, and FIG. 4B is an improper drive gear provided in the apparatus main body. A schematic side view showing a state in which the driven gears of various process cartridges are meshed with each other is shown in (c). Schematic side view showing the engaged state

FIG. 5 shows an embodiment different from that of FIG. 4, and (a) is a schematic side view showing a state in which a driven gear of a proper process cartridge is meshed with a driving gear provided in the apparatus main body (b). Is a schematic side view showing a state in which the driven gear of the improper process cartridge is engaged with the drive gear provided in the main body of the apparatus. (C) is a drive provided in the main body of the apparatus different from that shown in (a). Schematic side view showing a state in which a driven gear of an appropriate process cartridge is meshed with the gear

FIG. 6 shows an embodiment different from FIGS. 4 and 5,
(A) is a schematic side view showing a state in which a driven gear of a proper process cartridge is engaged with a drive gear provided in the main body of the apparatus. (B) is a drive gear provided in the main body of the apparatus Schematic side view showing a state in which the driven gears are meshed with each other. (C) is a state in which the driven gears of the proper process cartridge are meshed with the driving gears provided in the apparatus main body of a model different from that shown in (a). Schematic side view showing

[Explanation of symbols]

 1, 1A, 1B, 1C Device main body 2 Receiver (image forming device) 8, 8A, 8B, 8C Process cartridge 15 Photosensitive drum 16 Charger 17 Developing device 18 Cleaner device 19 Case 20, 20A, 20B, 20C Driven gear 23, 23A, 23B, 23C drive gear

Claims (1)

[Claims] 1. An apparatus main body having a drive gear, a case detachably provided to the apparatus main body, accommodating a driven body, and a drive provided on the apparatus main body side connected to the driven body. A developing device provided with a driven gear or the like that meshes with a gear to transmit rotation, and in the developing device, at least the case is made as a common part with other types of developing devices, and further, An image forming apparatus characterized in that the driving gear and the driven gear are helical gears configured to properly engage with each other only when a developing device is mounted on the main body of the apparatus and when a proper developing device is mounted on the main body of the apparatus. .