JP4936702B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus, and more particularly to an image forming apparatus having a mechanism for transporting waste toner to a waste toner container in an image forming apparatus such as a copying machine, a printer, or a facsimile machine.

As for the image forming apparatus, a so-called process cartridge is known in which at least one of a developing device, a charging device, a cleaning device, and the like, which are image forming means, and a photosensitive drum are integrally formed and detachable from the image forming device ( For example, see Patent Document 1).
Such a process cartridge has an advantage that a user can easily replace and maintain it without relying on a professional service person.
More specifically, the process cartridge includes a photosensitive drum and a container of a cleaning device that rotatably supports the photosensitive drum. Process means for forming an image by acting on the photosensitive drum is attached to the cleaning container. This process means includes a charging roller for uniformly charging the photosensitive drum, a cleaning blade and a cleaning roller for scraping off toner remaining on the photosensitive drum even after the toner image is transferred to a sheet-like medium (paper). These are attached so as to be positioned around the photosensitive drum.

  Further, the process cartridge is detachable from the image forming apparatus, and can be replaced by the user himself when the life of the photoconductor or the waste toner is full. Since the replacement timing of the process cartridge is basically based on the life of the photosensitive drum, the lifetime of the image forming means other than the photosensitive drum constituting the process cartridge is longer than that of the photosensitive drum (at least at the same time) ) Is set. The same applies not only to the image forming means but also to a container for storing waste toner. In a process cartridge in which the photosensitive drum and the cleaning container are integrated, the cleaning container is made of waste toner before the life of the photosensitive drum is exhausted. I try not to be full.

However, technological innovations in parts and materials / materials in recent years, downsizing of image forming means (for example, downsizing of a photosensitive drum and downsizing of a cleaning container, etc.) and downsizing of an output image (monochrome) Due to factors such as the output of more color photographs / graphic images than text images), the photoconductive drum, other image forming means, cleaning containers, etc. will have a life / replacement time shift, and the initially set balance relationship will be lost. It is coming. It is necessary to replace other image forming means and cleaning container before the life of the photosensitive drum expires, or other image forming means and cleaning container are still fully usable even when the life of the photosensitive drum is exhausted. There is a problem such as.
Therefore, in the process cartridge configuration in which the photosensitive drum and other image forming means and the cleaning container are integrally formed, when only one replacement is required, the entire process cartridge must be replaced. It is. Therefore, it is a cause of cost burden on the user and adverse effects on the environment.

  Therefore, the applicant of the present invention has applied for an invention (see, for example, Patent Document 2) regarding an image station that solves the problem of the process cartridge. As an embodiment in Patent Document 2, an image station is described using a two-station recording type image forming apparatus. The image station has an intermediate member (sub-side plate) with a photoconductor (or photoconductor unit), a developing device, A cleaning device is incorporated, and the positions of each other are maintained with high accuracy. With this configuration, the intermediate member (sub-side plate) is positioned with respect to the apparatus main body, so that this intermediate member (sub-side plate) serves as a position reference (assembly reference) for the entire image forming process element.

  More specifically, the developing device is integrally supported by an intermediate member (sub-side plate) and is supported by the apparatus main body via the intermediate member (sub-side plate). The intermediate member (sub-side plate) is positioned with respect to the apparatus main body, but is also detachable. A cleaning device (cleaning cassette) including a waste toner container is also incorporated in the intermediate member (sub-side plate). However, it is detachable as a single unit with respect to the intermediate member (sub-side plate). The cleaning device (cleaning cassette) is positioned only with respect to the intermediate member (sub-side plate) so as to keep the position with the developing device with high accuracy. Similarly to the cleaning device (cleaning cassette), the photoconductor (or photoconductor unit) is incorporated in the intermediate member (sub-side plate) and is detachable from the intermediate member (sub-side plate). . The photoconductor (or photoconductor unit) is positioned only with respect to the intermediate member (sub-side plate) so as to keep the position of the developing device and the cleaning device (cleaning cassette) with high accuracy. As described above, with the intermediate member (sub-side plate), it is necessary to replace something so that the positional relationship can be established with high accuracy using at least the photoconductor (or photoconductor unit), the developing device, and the cleaning device as an image station. In such a case, only the object can be exchanged so that it can cope with the difference in lifetime / replacement time.

Here, as briefly described above, a detailed explanation will be given of the reason why the life / replacement time has been shifted. In particular, recently, the shortening of the life of the photoconductor has become a problem, so the photoconductor will be mentioned.
In recent years, market demands for image forming apparatuses such as printers and copiers have become higher, and the load on image forming apparatuses in image formation has increased accordingly. The demand of the market has a direction to increase the load on the photosensitive member among the image forming means. This will be described below based on three factors.

2. Description of the Related Art In recent years, due to the widespread use of inkjet printers, electrophotographic printers are required to be miniaturized from the market due to the widespread use of inkjet printers, and accordingly, miniaturization of image forming apparatuses is also required. However, if the drum-shaped photoconductor as the image carrier is downsized, that is, the diameter is reduced, the degree of consumption of the photoconductor per sheet increases when an image is formed under the same conditions. For example, when the diameter of the photoconductor is reduced from 120 mm to 40 mm, it is necessary to rotate the photoconductor 3 times in order to form an image of the same size. Electrical consumption due to discharge at the charging unit and mechanical consumption due to the blade at the cleaning unit are tripled. Conventionally, development devices and the like have been downsized to some extent, but in order to avoid the above-described consumption of the photoreceptor, the diameter reduction has not been advanced as much as other image forming devices. However, as the demand for miniaturization increases, miniaturization of the photoreceptor is inevitable. Thus, the demand for downsizing increases the load on the photoreceptor and shortens its life.

In recent years, photographic images and graphic documents have been increasing in the number of documents output by users, and accordingly, the improvement in image quality aimed at silver halide photography has been promoted. A typical method is high resolution. However, when realizing high resolution in the electrophotographic system, it is required to reduce the thickness of the photoreceptor.
For example, in the case of a negatively charged photoconductor, a carrier formed by CGL (Charge Carrier Generation Layer) by exposure passes through a CTL (Charge Carrier Transport Layer) and reaches the surface of the photoconductor. A latent image is formed above, but if the CTL is thick at this time, the distance that the carrier moves increases, and as a result, the carriers move away from each other due to the electric repulsive force acting between the carriers during the movement. .
If such a situation occurs, a latent image according to the writing signal is not formed, and as a result, an image in which the dot positions are slightly shifted is formed and the image quality is impaired. Such a problem is not limited to the case of increasing the resolution of electrophotography from 600 dpi to 1200 dpi, but in the case of trying to improve the image quality while keeping the resolution at, for example, 600 dpi in order to meet the recent demand for higher image quality. It occurs in the same way.
In order to prevent such deterioration in image quality, it is necessary to reduce the thickness of the photoconductor and shorten the moving distance of the carrier. For this reason, in recent years, photoconductors have progressed in the direction of thinning, but since photoconductors have been worn out by cutting blades and the like each time an image is formed, the number of image formations can be reduced with the progress of thinning. The life of the body is exhausted, leading to a shortened life of the photoreceptor.

In recent years, the output of color images in the market has increased for reasons such as ease of understanding of information. By the way, color images, unlike monochrome images with many character images, are often output as photographic images and graphic images that occupy a wide area on a sheet-like medium (hereinafter referred to as paper) on which images are recorded. In many cases, a solid portion exists in the background. For this reason, the image forming area in one image formation increases, and the consumption of the image forming apparatus including the photosensitive member increases accordingly.

  On the other hand, a revolver type image forming apparatus in which a plurality of developing units correspond to one photoconductor is known. Such an image forming apparatus is widely used in the market because it can form a color image at a relatively low cost with a small number of parts. However, when a single color image is formed, the photosensitive member is a latent image formed by a plurality of developing units. Therefore, the photoconductor is consumed several times as much as the developer. For this reason, in such an image forming apparatus, the consumption of the photosensitive member accompanying the colorization becomes particularly severe. Thus, colorization is one of the factors that shorten the life of the photoreceptor.

  Due to the above-mentioned three factors of downsizing, high image quality, and colorization, it is expected that the photoconductor consumption will become relatively shorter than other image forming apparatuses. Of course, research on improving the durability and extending the life of the photoconductor is underway, but research on improving the durability and extending the life of other image forming devices is also ongoing, and the life of the photoconductor It tends to be relatively short.

This tendency leads to a life imbalance between the photosensitive member and other image forming means in the process cartridge. In other words, in the conventional process cartridge, the problem that the process cartridge has to be replaced in accordance with the image forming means having the shortest life has been pointed out. There is a negative effect of replacing other image forming means in accordance with the shortest-life photoconductor.
If such a situation occurs, the economic burden on the user due to the disposal or recycling of the imaging device that does not reach the end of its life, the waste of the manufacturer's collection labor, and the negative impact on the environment will occur.

  In particular, in recent years, research on extending the life of developers has progressed, and filming due to toner and carrier fatigue have been suppressed. As a result, the life of the developing device is in the direction of prolonging the life, so that the life of the developing device and the photoconductor is becoming unbalanced. In addition, in order to eliminate toner waste, development of a transfer technique of a toner image onto an intermediate transfer member or paper has been promoted, and transfer efficiency has been further improved. As a result, the residual toner on the photosensitive drum and the intermediate transfer member scraped off by the cleaning blade becomes very small. Considering transfer efficiency alone, the amount of waste toner tends to decrease, but there are factors that increase it further. Recent image forming apparatuses require high-precision process control and drive system control in order to cope with high image quality. To that end, toner patches and toner marks are separately provided on the photosensitive drum or intermediate transfer member in addition to the output image. A method is employed in which an image is formed, detected by a sensor, and controlled. To perform high-precision process control and drive system control, it is necessary to create images of toner patches and toner marks frequently. After detection / control by the sensor, the toner patches and toner marks are cleaned as soon as they are no longer needed. Since the mark is a solid image, the cleaning amount is larger than the remaining transfer amount.

  Conventionally, the factors that determine the capacity of waste toner containers have been photoconductor life (number of image formations, drum diameter) and transfer efficiency. It is becoming difficult to match the waste toner capacity. Accordingly, each manufacturer has increased the capacity of the waste toner container in consideration of the worst case. Therefore, the waste toner container becomes larger, and the full time of the waste toner container and the life of the photoconductor are becoming unbalanced.

  Therefore, as described many times, instead of configuring each image forming unit integrally as in the process cartridge, each image forming unit is individually replaced in accordance with the life of each unit, thereby burdening the user, manufacturer, and environment. Therefore, the present applicant has applied for an invention of an image station (see, for example, Patent Document 3). In Patent Document 3, as described above, in the image station, the photoconductor (or photoconductor unit), the cleaning cassette, and the developing device can be detachably attached, and the photoconductor (or photoconductor unit) having a short lifetime is given priority. It is disclosed that the exchange was made. Further, the image forming apparatus according to the embodiment of Patent Document 3 has a casing configuration that opens and closes to a crocodile mouth, and two image stations are arranged side by side in a lower casing so that a photoconductor (or photoconductor unit), a cleaning cassette, and the like. It is disclosed that the exchange workability is improved. In this configuration, the intermediate transfer belt unit is inevitably disposed in the upper housing, so that the intermediate transfer belt unit can be individually replaced, and the replacement workability is facilitated.

However, there are currently some problems with image stations, some of which are listed.
First of all, it was easy to replace the unit, but the number of user replacements increased. In addition, the cleaning cassette is separated from the photoconductor (or photoconductor unit), but the cleaning unit (cleaning blade, etc.) and the waste toner container are integrated. Strictly speaking, their lifetime / replacement time is different. Etc. The same can be said for the integration of the cleaning unit and the waste toner container for the intermediate transfer belt unit (for example, in the embodiment described in Patent Document 3, the waste toner container, the cleaning unit, and the intermediate transfer belt are integrated). . Considering the cost and environment, at least the waste toner container should not be integrated in the photoconductor (or photoconductor unit) and the intermediate transfer belt unit, and should be divided and replaced individually.

  As conventional examples in which the waste toner container is divided and the waste toner container is replaceable, there are Patent Documents 4 and 5, for example. Patent Document 4 discloses that a waste toner tank is disposed on an openable and closable side plate of a cassette bank section below an image forming section, and waste toner from a cleaning unit is collected through a waste toner conveyance path. Patent Document 5 discloses that a cleaning unit is provided in an upper body that can be opened and closed, a waste toner collection container is provided in a lower body, and waste toner is conveyed through a collection pipe. In both conventional examples, the cleaning unit and the waste toner container are divided.

However, since they are arranged in separate casings / side plates that can be opened and closed, when the casing / side plates are closed, the waste toner conveying pipe (nozzle) extending from the cleaning unit and the waste toner container are joined. However, when opened, either the waste toner transport pipe (nozzle) or the waste toner container is separated. In other words, when the housing / side plate is opened, the tip of the pipe (nozzle) (waste toner discharge port) and the opening of the waste toner container (waste toner inlet) are separated from each other, so there is a risk of toner leakage or toner scattering from both. There is .

In the case of an apparatus having a large number of exchange operations such as an image station by the present applicant, the number of operations further increases the problem. In other words, a large number of replacement operations means that the opening / closing frequency of the housing / side plate is increased, and the risk of toner leakage and toner scattering increases. In the invention described in Patent Document 6, a cap that opens and closes the waste outlet of the nozzle as the upper half 23 opens and closes is provided as a solution.
JP 2000-75733 A JP 2003-208073 A JP 05-289586 A Japanese Patent Laid-Open No. 08-006344 Japanese Patent No. 2553050

However, although the above-described problem can be improved by the cap, the nozzle outlet and the toner collection container 40 are separated each time the upper half 23 is opened. The problem of increasing the possibility of splashing remains and has not been solved.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming apparatus that prevents toner leakage and toner scattering when the casing is opened and closed in order to solve the conventional problems.

In order to solve the above-mentioned problems, an invention according to claim 1 of the present invention includes an image carrier that carries a visible image with toner, a transfer unit that transfers the visible image of the image carrier to a medium, and after transfer An image forming apparatus comprising at least a first cleaning unit that collects toner remaining on the image carrier and a waste toner storage unit that stores toner collected by the first cleaning unit. A housing that is a structure is composed of at least a main body housing and a sub-housing that is rotatable about a rotation fulcrum with respect to the main body housing, and the first cleaning unit is the main body housing. Or disposed in one of the sub-casings, the waste toner container is disposed in the other housing, and a waste toner conveyance path from the first cleaning unit to the waste toner container is provided Rotating fulcrum position of the housing Have a transport path portion through the image forming apparatus small constituted by Kutomo plurality of housings, a waste toner accommodating portion in a housing which is positioned in the gravity direction lower side disposed, gravity than the housing of its A first cleaning unit is disposed in a casing located on the upper side in the direction of gravity or a part having a portion extending on the upper side in the direction of gravity, and the waste toner container is located on the lower side in the direction of gravity with respect to the pivot point of the casing. It was placed, placing the direction of gravity above the first cleaning unit, waste toner yield capacity portion is provided with a first waste toner inlet of the rotary fulcrum coaxial to the rotational support position, the first cleaning unit waste toner a discharge port, bets first waste toner inlet is located in the gravity direction lower side of a position of the waste toner discharging port, the waste toner conveying path connects the first waste toner inlet and a waste toner discharge port toner A transport pipe is provided .

According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, there is a second cleaning unit that has a smaller amount of waste toner than the first cleaning unit, and the waste toner is discarded from each cleaning unit. The cleaning unit with the larger amount of toner is disposed on the housing side where the cleaning unit is installed, and the first cleaning unit is a housing or gravity that is located above the housing in which the waste toner container is disposed. The waste toner storage unit is disposed on a housing side having a portion extending upward in the direction, and includes a second waste toner inlet to which waste toner discharged from the second cleaning unit is conveyed. The second waste toner inlet is provided below the first waste toner in the direction of gravity.

According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect , the casing in which the cleaning unit is disposed is the rotating side, and the casing in which the waste toner storage unit is disposed is the non-moving side. It is characterized by.

According to a fourth aspect of the present invention, in the image forming apparatus according to the first or second aspect , the latent image carrier on which the electrostatic latent image is formed, and the electrostatic latent image is developed into a visible image using toner. The image carrier is an intermediate transfer member to which a visible image on the latent image carrier is transferred, and the visible image transferred to the image carrier is transferred to a recording medium. It is characterized by that.

According to a fifth aspect of the present invention, in the image forming apparatus according to the first or second aspect , the rotation fulcrum of the casing is configured by a hollow sleeve shaft, and waste toner passes through the sleeve shaft and is discarded from the cleaning unit. It reaches the toner container.

According to a sixth aspect of the present invention, in the image forming apparatus according to the first or second aspect , the rotation fulcrum of the housing is configured by a hollow sleeve shaft, and a toner conveying pipe is provided in the sleeve shaft. The waste toner passes from the cleaning unit to the waste toner storage unit through the pipe.

According to a seventh aspect of the present invention, in the image forming apparatus according to the first or second aspect , the waste toner container is detachable from the image forming apparatus.

According to an eighth aspect of the present invention, in the image forming apparatus according to the first or second aspect , the image forming apparatus includes two image carriers, a latent image carrier and an intermediate transfer member, each having a cleaning unit. The cleaning part of the image carrier, whichever is larger of the amount of waste toner and the amount of waste toner of the intermediate transfer member, is arranged on the upper side in the gravity direction with respect to the rotation fulcrum of the housing, The cleaning unit for the image carrier is disposed below the cleaning unit for the image carrier having the larger amount of waste toner in the direction of gravity.

The invention of claim 9, wherein, in the image forming apparatus according to claim 1 or 2, wherein a middle between transcript image bearing member with the larger amount of waste toner is, the cleaning portion of the intermediate transfer member of the housing It is arranged above the rotation fulcrum in the gravitational direction, and is configured such that the waste toner of the intermediate transfer member passes through the rotation fulcrum and reaches the waste toner storage unit, and the cleaning unit of the latent image carrier is the intermediate transfer It is characterized by being arranged on the lower side of the body cleaning portion in the direction of gravity.

Invention of claim 10, wherein, in the image forming apparatus according to claim 1 or 2, wherein, one with a lot of waste toner amount is said latent image bearing member, the pivot point of the housing the cleaning portion of the latent image bearing member The waste toner of the latent image carrier passes through a rotation fulcrum and reaches a waste toner storage portion, and the cleaning portion of the intermediate transfer member is disposed on the latent image carrier. It is characterized by being arranged below the cleaning unit in the direction of gravity.

The invention of claim 11 wherein the 請 The image forming apparatus according to any one of Motomeko 1 to 10, the latent image bearing member and two image bearing member either the cleaning-less means of medium between a transfer member when having a cleaning portion of the image bearing member towards having a cleaning unit arranged in the direction of gravity upward relative to the pivot point of the housing and toward the image bearing member which is provided with the cleaning-less means, said It is characterized in that it is arranged on the lower side in the gravitational direction than the image carrier on which the cleaning unit is provided, and at least one of them comprises two image carriers: a latent image carrier and an intermediate transfer member having a cleaning unit.

According to a twelfth aspect of the present invention, in the image forming apparatus according to the eleventh aspect , when the intermediate transfer member has a cleaning unit and the latent image carrier is a cleaningless unit, the cleaning unit of the intermediate transfer member is provided. It is arranged above the rotation fulcrum of the casing in the direction of gravity, and is configured such that waste toner of the intermediate transfer member passes through the rotation fulcrum and reaches a waste toner containing portion, and the latent image carrier is It is characterized by being arranged below the transfer body in the direction of gravity.

According to a thirteenth aspect of the present invention, in the image forming apparatus according to the eleventh aspect , when the latent image carrier has a cleaning unit and the intermediate transfer member is a cleaning-less means, the cleaning unit for the latent image carrier. Is disposed on the upper side in the direction of gravity with respect to the rotation fulcrum of the housing, and the waste toner of the latent image carrier passes through the rotation fulcrum and reaches the waste toner storage unit, and the intermediate transfer member is The latent image carrier is arranged below the gravitational direction.

A fourteenth aspect of the present invention is the image forming apparatus according to any one of the first to thirteenth aspects, further comprising a plurality of latent image carriers, each of the plurality of latent image carriers having a cleaning unit, and each latent image carrier. The present invention is characterized in that the waste toner discharged from the image bearing member cleaning section passes through a common waste toner transport path and reaches the waste toner storage section.

According to the first aspect of the present invention, even when the cleaning unit and the waste toner storage unit are provided in separate housings, the problems of toner leakage and toner scattering due to the opening and closing of the housing can be solved, and the conveyance path is simplified. Hakare is compact apparatus, the waste toner storage capacity and smooth waste toner conveying can and Fuyasuko.

According to the second aspect of the present invention, the problem of toner leakage and toner scattering can be solved, the waste toner full time can be delayed, and the replacement frequency of the waste toner storage section can be reduced.

According to the third aspect of the present invention, it is possible to solve the problem of toner leakage and toner scattering when the casing is opened and closed.

According to the fourth aspect of the present invention, the waste toner from the image carrier and / or the transfer body can be conveyed to the waste toner storage unit without problems of toner leakage and toner scattering.

According to the fifth aspect of the present invention, the reliability of the casing opening / closing operation and the durability are improved, and the problems of toner leakage and toner scattering are solved.

According to the sixth aspect of the present invention, at lower cost than the invention of claim 6, the reliability of the casing opening and closing operation, the durability is improved, eliminating the occurrence of toner leakage and toner scattering problem.

According to the invention described in claim 7 , it is possible to replace only the waste toner storage portion whose replacement time has come.

According to the eighth aspect of the present invention, the amount of waste toner on the latent image carrier (photosensitive member) and the amount of waste toner on the intermediate transfer member are compared, and the cleaning unit with the larger amount of waste toner is placed on the rotation fulcrum. By disposing the toner on the upper side in the gravitational direction, a larger amount of waste toner passes through the rotation fulcrum and reaches the waste toner container, so that toner leakage and toner scattering can be suppressed. At the same time, the position of the cleaning unit and the rotation fulcrum with the larger amount of waste toner is set to the upper part of the image forming apparatus (the cleaning unit of the image carrier with the larger amount of waste toner is positioned above the rotation fulcrum). Therefore, the waste toner storage capacity with the larger amount of waste toner can be increased, and the replacement frequency of the waste toner storage unit can be reduced.

According to the ninth aspect of the present invention, when the waste toner amount is the intermediate transfer member, toner leakage and toner scattering from the cleaning portion of the intermediate transfer member having a large amount of waste toner can be suppressed. At the same time, the position of the cleaning unit and the rotation fulcrum of the intermediate transfer member with a large amount of waste toner is set to the upper part of the image forming apparatus (the cleaning unit of the intermediate transfer member is positioned above the rotation fulcrum). The waste toner storage capacity can be increased, and the replacement frequency of the waste toner storage section can be reduced.

According to the tenth aspect of the present invention, when the larger amount of waste toner is the latent image carrier (photoreceptor), toner leakage from the cleaning portion of the latent image carrier (photoreceptor) having a larger amount of waste toner Toner scattering can be suppressed. At the same time, the position of the cleaning unit and rotation fulcrum of the latent image carrier (photoreceptor) with a large amount of waste toner is set to the upper part of the image forming apparatus (the cleaning unit of the latent image carrier (photoreceptor) is Therefore, the waste toner storage capacity of the latent image carrier (photosensitive member) can be increased, and the replacement frequency of the waste toner storage unit can be reduced.

According to the eleventh aspect of the present invention, when either one of the latent image carrier (photosensitive member) and the intermediate transfer member has the cleaning-less means, the cleaning unit provided with the cleaning unit is moved with respect to the rotation fulcrum. By disposing the toner cartridge on the upper side in the gravity direction, the waste toner provided with the cleaning unit passes through the rotation fulcrum and reaches the waste toner storage unit, so that toner leakage and toner scattering can be suppressed. At the same time, the position of the cleaning unit provided with the cleaning unit and the rotation fulcrum are set to the upper part of the image forming apparatus (the cleaning unit of the image carrier having the larger amount of waste toner is positioned above the rotation fulcrum). Therefore, the waste toner storage capacity of the one provided with the cleaning unit can be increased, and the replacement frequency of the waste toner storage unit can be reduced.

According to the twelfth aspect of the present invention, when the intermediate transfer member is provided with a cleaning portion and the latent image carrier (photosensitive member) is a cleaning-less means, toner leakage or toner scattering from the cleaning portion of the intermediate transfer member is prevented. Can be suppressed. At the same time, the intermediate transfer member cleaning unit and the rotation fulcrum are positioned above the image forming apparatus (the intermediate transfer member cleaning unit is positioned above the rotation fulcrum). And the replacement frequency of the waste toner storage unit can be reduced.

According to the thirteenth aspect of the present invention, when the latent image carrier (photosensitive member) is provided with a cleaning unit and the intermediate transfer member is a cleaning-less means, the toner from the latent image carrier (photosensitive member) cleaning unit is provided. Leakage and toner scattering can be suppressed. Along with this, latent image carrier (photoreceptor)
The position of the cleaning unit and the rotation fulcrum of the latent image carrier (photoreceptor) is positioned above the image forming apparatus (the cleaning unit of the latent image carrier (photoreceptor) is located above the rotation fulcrum). The waste toner storage capacity can be increased and the replacement frequency of the waste toner storage unit can be reduced.

According to the fourteenth aspect of the present invention, the waste toner from each cleaning unit of the plurality of latent image carriers (photoconductors) passes through the rotation fulcrum and is conveyed to the waste toner storage unit. Since this pipe is shared, toner leakage and toner scattering can be suppressed. At the same time, it can contribute to space saving of the image forming apparatus, reduction of the number of parts, simplification of the configuration, and the like.

  According to the present invention, even if the cleaning unit and the waste toner storage unit are arranged in separate housings, the rotation fulcrum position of the housing is used as the waste toner transport path, so that the problem of toner leakage and toner scattering due to opening and closing of the housing is solved. In addition, the conveyance path can be simplified and the apparatus can be made compact. Furthermore, the amount of waste toner on the latent image carrier (photosensitive member) and the amount of waste toner on the intermediate transfer member are compared, and the cleaning unit with the larger amount of waste toner is placed above the rotation fulcrum in the direction of gravity. Further, since a larger amount of waste toner passes through the rotation fulcrum and reaches the waste toner container, toner leakage and toner scattering can be suppressed. At the same time, the position of the cleaning unit and the rotation fulcrum with the larger amount of waste toner is set to the upper part of the image forming apparatus (the cleaning unit of the image carrier with the larger amount of waste toner is positioned above the rotation fulcrum). Therefore, the waste toner storage capacity with the larger amount of waste toner can be increased, and the replacement frequency of the waste toner storage unit can be reduced.

  The image forming apparatus of the present embodiment includes an image carrier on which an electrostatic latent image is formed, a developing unit that develops the electrostatic latent image into a visible image using toner, and the developed visible image in a sheet form In an image forming apparatus comprising at least a transfer unit that transfers to a medium, a cleaning unit that removes excess toner on an image carrier, and a waste toner storage unit that stores waste toner that has been cleaned by the cleaning unit, The housing, which is the structure of the image forming apparatus, includes at least a main body housing and a sub housing that can be rotated around a rotation fulcrum with respect to the main body housing, and the cleaning unit Disposed in one of the housings, the waste toner container is disposed in the other housing, and the waste toner transport path from the cleaning unit to the waste toner container passes through the rotation fulcrum position of the housing It has a route part To.

  In addition to the above configuration, the image forming apparatus according to the present embodiment includes at least a plurality of casings, and a waste toner container is disposed in a casing located on the lower side in the gravitational direction. The cleaning unit may be arranged in a case located on the upper side in the gravity direction or a case having a portion extending in the upper side in the direction of gravity, and the waste toner container is provided on the lower side in the direction of gravity with respect to the rotation fulcrum of the case. The cleaning unit may be arranged on the upper side in the direction of gravity, and there are a plurality of cleaning units, and the cleaning unit with the larger amount of waste toner discharged from each cleaning unit is disposed on the side of the housing where the cleaning unit is installed. Alternatively, the cleaning unit having a plurality of cleaning units and having a larger amount of waste toner discharged from each cleaning unit may be disposed on the housing side where the cleaning unit is installed.

  In addition to the above configuration, the image forming apparatus according to the present embodiment may be configured such that the housing in which the cleaning unit is disposed is the rotation side and the housing in which the waste toner storage unit is disposed is the non-moving side. It may be a cleaning device that cleans residual toner on the body and a cleaning device that cleans residual toner on the transfer unit or any one of the transfer bodies, and the rotation fulcrum of the housing is constituted by a hollow sleeve shaft, The waste toner may pass through the sleeve shaft and reach from the cleaning unit to the waste toner storage unit, and the rotation fulcrum of the housing may be a hollow sleeve shaft, and the toner shaft may be used for conveying toner. A pipe may be provided so that waste toner passes from the cleaning unit to the waste toner storage unit through the pipe, and the waste toner storage unit is detachable from the image forming apparatus. Good.

  In addition to the above-described configuration, the image apparatus according to the present embodiment includes two image carriers, a latent image carrier and an intermediate transfer member each having a cleaning unit. The amount of waste toner on the latent image carrier and the intermediate transfer member The cleaning part of the image carrier that has the larger amount of waste toner is arranged above the rotation fulcrum of the housing in the direction of gravity, and the cleaning part of the image carrier that has the smaller amount of waste toner is disposed of the amount of waste toner. It may be disposed below the cleaning portion of the larger image carrier, in the direction of gravity, and the image carrier having the larger amount of waste toner is the intermediate transfer member, and the cleaning portion of the intermediate transfer member is connected to the casing. It is arranged above the moving fulcrum in the gravitational direction so that the waste toner of the intermediate transfer member passes through the rotation fulcrum and reaches the waste toner container, and the cleaning portion of the latent image carrier is used as the cleaning portion of the intermediate transfer member. You may arrange | position to the gravity direction lower side.

  In addition to the above-described configuration, the image device according to the present embodiment is a latent image carrier that has a larger amount of waste toner, and the cleaning unit of the latent image carrier is disposed above the rotation fulcrum of the housing in the direction of gravity. The waste toner of the latent image carrier may be configured to reach the waste toner container through the rotation fulcrum, and the cleaning unit of the intermediate transfer member may be disposed below the cleaning unit of the latent image carrier in the gravity direction. Well, when one of the two image carriers, the latent image carrier and the intermediate transfer member, has a cleaning-less means, the cleaning portion of the image carrier provided with the cleaning portion is moved with respect to the rotation fulcrum of the housing. Alternatively, the image bearing member provided with the cleaning-less means may be disposed on the lower side in the gravity direction than the image bearing member provided with the cleaning unit.

  In addition to the above-described configuration, the image apparatus according to the present exemplary embodiment has a cleaning unit that has a cleaning unit and the latent image carrier is a cleaning-less unit. The intermediate transfer member is configured such that the waste toner of the intermediate transfer member passes through the rotation fulcrum and reaches the waste toner container, and the latent image carrier is disposed below the intermediate transfer member in the gravity direction. Well, when the latent image carrier has a cleaning portion and the intermediate transfer member is a cleaning-less means, the latent image carrier's cleaning portion is disposed above the rotation fulcrum of the housing in the direction of gravity so that the latent image It may be configured such that the waste toner on the carrier passes through the rotation fulcrum and reaches the waste toner container, and the intermediate transfer member may be disposed below the latent image carrier in the gravity direction.

  In addition to the above-described configuration, the image apparatus of the present embodiment includes a plurality of latent image carriers, each of which has a cleaning unit, and the waste discharged from the cleaning unit of each latent image carrier. The toner may be configured to reach the waste toner storage unit through a common waste toner conveyance path.

An example of the two-station recording type intermediate transfer type color image forming apparatus according to the present embodiment is disclosed in Japanese Patent Application Laid-Open No. H10-228707. The present invention will be described using the two-station image forming apparatus.
First, the outline of the two-station image forming apparatus will be described with reference to FIG.
FIG. 1 is a conceptual diagram of an image forming apparatus which is a premise of the present invention.
In FIG. 1, an intermediate transfer belt unit 1000 extends a belt 100 as an intermediate transfer medium between two rollers 120 and 130 that are provided to be opposed to each other, and the belt 100 is rotated by these rollers 120 and 130. The image forming process means is disposed around the belt 100.
Assuming that the rotation direction of the belt 100 is an arrow “a”, as a process means for image formation in order from the upstream side in the rotation direction of the belt 100 between the roller 120 and the roller 130 and below the belt 100, The first image station 140, the second image station 240, a transfer roller 98 as a transfer means provided so as to be able to come in contact with and away from the roller 130, a cleaning blade 61a provided so as to be able to come into contact with and away from the roller 120, etc. Is arranged.

If attention is paid to the first image station 140, the image forming process is based on a general electrostatic recording method, and is provided by the optical writing unit 180 on the photosensitive member 160 uniformly charged by the charging means in the dark. A color electrostatic latent image is written, the electrostatic latent image is visualized by the developing device 60, and the toner image is transferred to the belt 100. The transferred photoconductor 160 is cleaned by the cleaning blade 210a.
The developing device 60 in the first image station 140 and the developing device 80 in the second image station 240 each have a visible image forming function using two different color toners.

On the other hand, black is added to the three primary colors to form four colors. If these four colors are assigned to each developing unit, magenta developing unit 190, cyan developing unit 200, yellow developing unit 290, and black developing unit 300, full color. An image can be formed.
Therefore, while the same image forming area of the belt 100 sequentially passes through the two image stations 140 and 240, an intermediate transfer provided opposite to the drum-shaped photoconductors 160 and 260 with the belt 100 therebetween. The toner image is transferred onto the belt 100 by a transfer bias applied by the transfer brushes 410 and 420 as means, and the image area on which the two colors are transferred onto the belt 100 is once again transferred to the above-mentioned image area. If the toner images of different colors from each other are transferred and transferred by the image stations while sequentially passing through the two image stations 140 and 240, the same image forming region is transferred to the image stations 140 and 240. When it passes twice, full color toner is transferred onto this same image area by overlapping transfer. Image can be obtained.

  The full-color toner image is transferred to a sheet P as a sheet-like medium. In this transfer, a transfer bias is applied to the transfer roller 98 for final transfer that is brought into pressure contact with the roller 130 via the belt on the roller 130 at the time of transfer. This is done by passing. After the final transfer, the full-color toner image carried on the transfer paper P is fixed by the fixing unit 90 to obtain a full-color final image on the paper P.

FIG. 2 shows a cross section of an embodiment to which the image forming apparatus of the present invention is applied.
The image forming apparatus shown in FIG. 2 is roughly divided into a transfer sheet storage unit 70A and a feeding roller 70B, a writing device 180, developing devices 60 and 80, an intermediate transfer belt unit 1000, a fixing unit 90, and an electrical device in order from the lower part in the direction of gravity. There is a substantially vertical sheet conveyance path constituted by a manual feed roller 97, registration rollers 96a and 96b, a transfer roller 98, and the like, and is fed from the transfer sheet storage unit 70A. The paper roller 70 </ b> B extends upward from the paper transfer portion, which is a contact portion between the transfer roller 98 and the roller 130 → the fixing portion by the fixing device 90 → the waste paper portion 99.
The writing unit 180 can be configured by an optical system using a light emitting diode LED as a light source, but can also be configured by a laser optical system using a semiconductor laser as a light source, and a drum as an image carrier described in detail later. The photoconductors 160 and 260 having a shape are exposed in accordance with image information. More specifically, laser light corresponding to image information is emitted toward a polygon mirror 180a that is vertically superimposed by two semiconductor lasers (not shown). The light reflected by the polygon mirror 180a passes through the scanning lenses 180b and 180c and the reflection mirror 180d and rotates through a window (not shown) provided in the upper cover 180f parallel to the scanning direction. The exposure positions 160 and 260 are reached to form an image.
Each optical component is positioned and fixed to a housing 180e that also serves as a base of the apparatus main body casing (lower casing 1050). In this example, a two-beam laser scanning system is used, but the writing method and configuration are not limited to this. In this embodiment, since the writing device 180 is below the photoconductors 160 and 260, it is not necessary to provide an opening for allowing writing light to pass through the housing 180e that supports the writing device 180 from below, and the strength of the housing 180e. It is possible to improve. The latent image forming and developing means is composed of a photosensitive cassette, a cleaning cassette which is an example of a cleaning device, and a developing device mainly comprising three cassettes and devices, which serve as intermediate members supporting the developing device. An image station is configured as a unit by sub-side plates. Two image stations configured in the same manner by the same member are arranged in parallel on the left and right, and the left side in FIG. 2 is a first image station 140 and the right side is a second image station 240.
Since the two image stations have the same configuration except for the color of the toner used, the configuration of the image station will be described using the first image station 140 here.

Before that, a schematic image of the image station will be described with reference to FIG.
FIG. 3 is a schematic view of the first image station 140 of FIG. 2 as viewed from above.
The sub-side plates A and B located inside the main body side plates 3000 and 4000 constituting the lower casing 1050 are connected to each other by a stay and a shaft (not shown) so that the determined dimensional spacing and parallelism can be maintained with high accuracy. Has been. Both sides of the developing device 60 are supported on the inner side of the sub side plates A and B by a rotating shaft 60P and the like, and are positioned so as to be rotatable so that the color of the developing device can be switched. Therefore, the sub side plates A and B and the developing device 60 are integrated. The size and shape of the sub side plates A and B are covered by the development side parts such as gears and shafts provided on both sides 60C and 60D of the developing device 60 and the developing components such as the toner supply port. Size and shape to be protected. The sub-side plates A and B support the photosensitive cassette 1400 and the cleaning cassette 220 so that they can be individually rotated and detached. The developing device 60, the photosensitive cassette 1400, and the cleaning cassette 220 are integrated by such sub-side plates A and B to form the first image station 140. The formed first image station 140 is installed and fixed to the positioning portions of the main body side plates 3000 and 4000 by the sub side plates A and B. The sub side plates A and B (at least together with the developing device 60) can be attached to and detached from the main body side plates 3000 and 4000 (lower casing 1050).

Further, a waste toner cassette 1 for storing waste toner from the cleaning cassette 220 is provided outside the main body side plate 3000 so that it can be detached from the apparatus main body. The cleaning cassette 220 and the waste toner cassette 1 are connected by a hollow pipe 2 to prevent toner leakage and toner scattering at the joint portion between the two. Further, the waste toner cassette 1 can be moved in the left-right direction in FIG. 3, the pipe 2 can be slid in the direction of arrow b (left-right direction in FIG. 3), and the cleaning cassette 220 and the waste toner cassette 1 are individually provided from the pipe 2. It can be easily attached and detached. The pipe 2 has flexibility so that the cleaning cassette 220 can freely rotate with respect to the sub-side plates A and B, and the waste toner is conveyed from the cleaning cassette 220 to the waste toner cassette 1 in the pipe 2. The coil spring 2a (broken line in the figure) is provided.
Returning to FIG. 2, the description of the configuration of the first image station 140 is continued (the sub-side plates A and B and the waste toner cassette 1 are not shown in order to make the drawing easier to see).

FIG. 4 shows an enlarged view of the first image station 140 of FIG.
The photoconductor cassette 1400 includes a photoconductor 160 and a holder 1410 that protects and rotatably supports the photoconductor 160. That is, unlike the conventional process cartridge, the photosensitive drum and other process means are not integrated.
The photosensitive member 160 is connected to a driving motor provided in the main body of the image forming apparatus via a drive transmission system (160g in FIG. 3) such as a gear coaxial with the photosensitive member 160 so as to rotate clockwise. It has become. In order to increase the relative position between the photoconductor 160 and the developing rollers 320 and 330, the photoconductor cassette 1400 includes a sub-side plate A that supports the developing device 60 including the developing rollers 320 and 330 with high accuracy. B is positioned with respect to B. In order to improve the relative position between the photoconductor 160 and the cleaning unit 210 and the roller-shaped charger 170 described later, a charger is provided for the photoconductor cassette 1400 positioned with high accuracy on the sub-side plates A and B. The cleaning cassette 220 supporting the cleaning means 210 is positioned in the cassette case 60f that pivotally supports 170. There is also a contact / separation relationship in which the cleaning cassette 220 side is operated by the sub-side plates A and B with respect to the photosensitive cassette 1400 (rotation in the direction of arrow c in FIG. 4).
By configuring the configuration of the photoconductor cassette 1400 and the relationship between the developing device 60 and the cleaning cassette 220 with respect to the photoconductor cassette 1400 as described above via the sub-side plates A and B, only the photoconductor 160 can be replaced. Become. That is, the replacement timing of the photosensitive cassette 1400 can be determined only by the lifetime of the photosensitive member 160. This concept is the point of the image station, which is a big difference from the conventional process cartridge. In order to avoid waste as in the past, only the things that should be replaced are exchanged, and those that can be used are not exchanged. Further, since the sub-side plates A and B are detachable, that is, the developing device 60 can be replaced, it is possible to cope with a failure replacement of the developing device 60, and at that time from the sub-side plates A and B. Since the photosensitive member cassette 1400 and the cleaning cassette 220 can be removed, the developing device 60 is replaced alone, eliminating waste. Furthermore, when the user takes out the developing device, there is a high risk of touching the developing driving parts such as gears and shafts provided in the developing device and the developing components such as the toner replenishing port, and soiling hands and clothes or causing injury. When the removed developing device is placed outside the image forming apparatus, the exposed parts or parts may directly collide with the floor surface or the parts or parts may be damaged or broken.

Therefore, in order to protect both the user and the developing device, the sub-side plates A and B cover the exposed parts and parts.
If only the photosensitive cassette 1400 can be removed from the image forming apparatus main body before the developing device 60 and the cleaning cassette 220, the replacement workability of the photosensitive cassette 1400 having a high replacement frequency can be improved. The process element having the highest replacement frequency is the photoconductor 160, that is, the photoconductor cassette 1400. When the photoconductor cassette 1400 is frequently replaced, the developing device 60 and the cleaning cassette 220 that do not need to be replaced are replaced with the sub-side plate A, Removing with B at the same time is cumbersome and has low applicability, and causes additional problems such as dirtying hands and surroundings.
Therefore, in order to solve such a problem, only the things to be replaced are removed, the unnecessary ones are not removed, and the ones that are frequently exchanged can be preferentially removed. This idea is also one of the points of the image station, which is a big difference from the conventional process cartridge.

In this embodiment, the image forming apparatus main body and other cassettes and apparatuses constituting the image station are also configured based on the above-described concept. In this embodiment, the photoconductors 160 and 260 are described as drum-shaped, but may be configured as a belt. Here, the life of the photoconductor 160 that determines the replacement timing of the photoconductor cassette 1400 will be described. The technological progress of the photoconductor material in recent years has been remarkable, and the life of the photoconductor has been extended to about 400K to 500K sheets (conventional technology). 4-5 times).
However, on the other hand, the required specifications for the image forming apparatus, such as a reduction in the diameter of the photosensitive member due to downsizing / lightening of the apparatus, and a case where there are a plurality of developing units for one photosensitive member as in the example of FIG. The composition conditions are going to be stricter.
For this reason, the photoreceptor is being overused and used to accelerate fatigue deterioration, and this tendency is getting stronger. That is, no matter how much the life and durability of the photoreceptor material are improved, it is natural that the replacement frequency is not reduced if it is overused, and it can be assumed that the reduction is not expected much in the future. As in the prior art, the frequency of replacement of the photoconductor is still the highest compared to other process elements (other process elements are also becoming longer in life).

Next, the cleaning cassette 220 will be described.
The cleaning cassette 220 includes a cleaning unit 210 including a cleaning blade 210a as a cleaning unit that removes residual toner and dust on the surface of the photoconductor 160, and a seal roller 210b that prevents toner scattering during cleaning, and the removed residual toner. A cleaning container 270 is integrated with a screw 210c that conveys waste and dust to the waste toner cassette 1.
The seal roller 210b and the screw 210c are rotatably supported by the cleaning container 270, and are connected to the photoconductor 160 by a gear train (not shown). The cleaning cassette 220 is housed and fixed in a rotatable cassette case 60f that is integral with the sub-side plates A and B, so that the relative position with respect to the photoreceptor cassette 1400 and the photoreceptor 160 is positioned with high accuracy. . The cleaning cassette 220 is also detachable from the cassette case 60f so that it can be replaced independently. That is, the cleaning cassette 220 is positioned and fixed on the sub-side plates A and B in the same manner as the photoconductor cassette 1400 and is detachable independently, and can be contacted and separated from the photoconductor cassette 1400. The waste toner is transported from the cleaning container 270 to the waste toner cassette 1 by the waste toner discharge port 220a of the cleaning container 270 on the extension line of the screw 210c (on the front side in FIG. 4) and the waste toner inlet of the waste toner cassette 1. This is performed by connecting 1a with a pipe 2 (see FIG. 3).

FIG. 5 shows a front view of the waste toner cassette 1 so that the positional relationship between the cleaning cassette 220 and the waste toner cassette 1 can be easily understood.
The 1c part of the long hole shape arranged side by side is a grip part for attachment or detachment.
As described above, the cleaning container 270 is a type that does not include a waste toner container. In the case of this embodiment, unlike the conventional example, the divided cleaning cassette 220 and waste toner cassette 1 are not arranged in separate housings, but are arranged on the main body side plate which is the same housing. (Toner leakage or toner scattering due to separation of the waste toner discharge port 220a and the waste toner inlet 1a when the housing is opened) does not occur. The charger 170 is a roller-shaped charging unit that uniformly charges the surface of the photoconductor 160, is supported by the cassette case 60f, and is connected to the photoconductor 160 by a gear train (not shown). Similarly to the cleaning cassette 220, the charger 170 is also detachable from the cassette case 60f so that the relative position with respect to the photosensitive cassette 1400 and the photosensitive member 160 is positioned with high accuracy and can be replaced independently. That is, the charger 170 is also positioned and fixed on the sub-side plates A and B in the same manner as the photoconductor cassette 1400 and the cleaning cassette 220, and can be attached and detached independently in consideration of the problem of life / replacement time. Both can be connected and separated.
The description of more specific image station configuration functions and attachment / detachment work procedures is the same as that of Patent Document 3 except that the cleaning cassette 220 and the waste toner cassette 1 are divided, and a description thereof will be omitted.

By configuring the image station as described above, the problem of the process cartridge, the problem of the conventional image station (the life of the cleaning unit and the waste toner container / difference time), and the toner generated around the photoconductor cleaning by opening and closing the housing Leakage and toner scattering problems are eliminated.
However, in the image forming apparatus according to the present embodiment, since the image stations 140 and 240 and the cassettes and apparatuses thereof, and the intermediate transfer belt unit 1000 are easily exchanged, the casing is configured to be opened and closed. When the image station including the waste toner cassette 1 and the waste toner cassette 1 are installed in the same casing (lower casing 1050) as described above, the intermediate transfer belt unit 1000 is provided in the upper casing 1060 which is a separate casing ( (See FIG. 6).

FIG. 6 is an image when the main housing is opened. The intermediate transfer belt unit 1000 includes a cleaning unit, but does not include a waste toner storage unit in consideration of the difference in lifetime / replacement time like the image station.
However, the arrangement of the intermediate transfer belt unit 1000 and the waste toner cassette 1 in separate housings means that toner leakage or toner is generated around the joint between the cleaning portion of the intermediate transfer belt unit 1000 and the waste toner cassette 1 when the housing is opened and closed. I'm worried about the scattering. That is, the same problem as that in Patent Documents 4 and 5 occurs for the same reason. In the present application, since the problem, that is, the problem due to the separate housing arrangement of the cleaning unit and the waste toner container housing unit, has been solved, a description will be given.

First, the intermediate transfer belt unit 1000 of this embodiment disposed in the upper housing 1060 will be described with reference to FIG.
As described with reference to FIG. 1, the image forming apparatus includes the intermediate transfer belt 100 and is stretched between the rollers 130 and 120, the transfer brushes 410 and 420 for primary transfer, the cleaning device 61, and the like. Thus, the intermediate transfer belt unit 1000 is configured. The intermediate transfer belt unit 1000 is detachably provided on the upper casing 1060 of the apparatus main body. A first image station 140 and a second image station 240 are arranged on the lower running surface of the intermediate transfer belt 100 at regular intervals along the running direction of the intermediate transfer belt 100. Either of the rollers 130 and 120 may be used as a drive roller, but the intermediate transfer belt 100 is an integral multiple of the circumference of the roller used as the drive roller, and is at least less than the length in the moving direction of the maximum size transfer paper used. Longer than the image area. The running of the intermediate transfer belt 100 is synchronized with the rotation of the photoconductors 160 and 260, and the linear velocity is also set to coincide with high accuracy.
Further, transfer brushes 410 and 420 are provided on the photoconductors 160 and 260 for primary transfer with the intermediate transfer belt 100 interposed therebetween.

In the first image station 140, the transfer brush 410 and the insulating holder 370 are fixed to the bracket BC. The holder 370 is rotatably provided with a transfer roller 390 at a position slightly away from the transfer brush 410. The reason why the transfer brush 410 and the transfer roller 390 are spaced is that the intermediate transfer belt 100 is brought into contact with the photosensitive member 160 with a predetermined nip width, and in this state, a bias is applied to the transfer brush 410 and the transfer roller 390 with a potential difference. This is because the transfer performance can be improved by applying a voltage. In this embodiment, the transfer brush 410 and the transfer roller 390 are always in contact with the intermediate transfer belt 100. However, in order to avoid bending, wear, and toner adhesion, the toner image on the photoconductor 160 is intermediate. The transfer brush 410 and the transfer roller 390 may be controlled to swing so as to come into contact with the intermediate transfer belt 100 only during the primary transfer process of transferring to the transfer belt 100. The transfer device may be a roller type instead of the transfer brush 410.
A transfer roller 98 for secondary transfer for transferring the toner image on the intermediate transfer belt 100 to the transfer paper P is provided facing the roller 130 so as to be able to contact and separate with the intermediate transfer belt 100 interposed therebetween. It constitutes the next transfer section.

A cleaning device 61 that removes and transports residual toner on the surface of the intermediate transfer belt 100 is provided opposite to the roller 120. The cleaning device 61 urges the bracket 61 c in a direction in which the cleaning blade 61 a that can be brought into contact with and separated from the intermediate transfer belt 100, a bracket 61 c that fixes the cleaning blade 61 a, and the cleaning blade 61 a is pressed against the intermediate transfer belt 100. It consists of elastic means 61b such as a spring and a waste toner conveying screw 61g provided at the lower part of the cleaning blade 61a.
The bracket 61c is rotatably supported on a side plate (not shown) of the intermediate transfer belt unit 1000, and is connected to contact / separation means (not shown). By controlling the contact / separation means, the bracket 61c is rotated so that the cleaning blade 61a is separated from the intermediate transfer belt 100 against the urging force of the elastic means 61b, or the state is maintained, or FIG. As shown in FIG. 8, the rotating force of the contact / separation means is released, and the cleaning blade 61a can be brought into contact with the intermediate transfer belt 100 by the urging force of the elastic means 61b. The residual toner removed by the cleaning blade 61a is sent as waste toner by a screw 61g, and sent to the waste toner cassette 1 through a pipe 4 (described later) (see FIG. 5). The waste toner cassette 1 of this embodiment uses a common waste toner cassette that stores both the waste toner of the image stations 140 and 240 and the waste toner of the intermediate transfer belt unit 1000.

  In the configuration of FIG. 2, the image stations 140 and 240 and the intermediate transfer belt unit 1000 that are unitized as described above are individually detachably attached to the apparatus main body, and the entire apparatus is shown in FIG. Similarly, the image stations 140 and 240, the writing unit 180, etc. and other image forming components are housed in a lower housing 1050 including main body side plates 3000, 4000, the intermediate transfer belt unit 1000, the fixing device 90, etc. These image forming components are housed in the upper housing 1060. Further, one registration roller 96b, a transfer roller 98 for secondary transfer, and the like, and other image forming components are housed in the front housing 1070. When performing operations such as maintenance and replacement of the image forming parts such as the photoconductors 160 and 260 and the intermediate transfer belt 100 housed in the lower casing 1050 and the upper casing 1060, and each image forming component, and jam processing work For example, the upper housing 1060 and the front housing 1070 that open in a crocodile shape with respect to the lower housing 1050 are opened around the pivot fulcrums 75 and 76, and each unit and device is attached or detached, or jammed paper is removed. Or remove it.

The above is a general description of the main body configuration and the intermediate transfer belt unit 1000 disposed in the upper housing 1060. Next, the relationship between the intermediate transfer belt unit 1000 and the waste toner cassette 1 will be described.
FIG. 7 is a schematic image view of a part of the periphery of the cleaning device 61 of the intermediate transfer belt unit 1000 of FIG. 2 as viewed from above.
The side plate 5000 is a member constituting the upper housing 1060. The main body side plate 3000 of the lower housing 1050 has an inward protruding portion 75a formed by pressing, and a hole 75b is provided in the side plate 5000 so as to correspond thereto. The rotation fulcrum 75 is formed by fitting them. If the same is applied to the opposite main body side plate 4000 side, the upper housing 1060 can be rotated with respect to the lower housing 1050. The intermediate transfer belt unit 1000 is supported by the upper housing 1060 by inserting the bearing 120a of the roller 120 protruding from the side plate of the intermediate transfer belt unit 1000 into the receiving member C provided inside the side plate 5000, and is positioned with high accuracy. Is done.

  Note that the intermediate transfer belt unit 1000 can be moved in the downward direction in FIG. 7 (in the direction of arrow x in FIG. 6) so that it can be replaced. The waste toner cassette 1 installed at a position outside the main body side plate 3000 and also outside the side plate 5000 and the cleaning device 61 of the intermediate transfer belt unit 1000 are connected by a hollow pipe 4, and at the joint portion between them. This prevents toner leakage and toner scattering. The pipe 4 has a built-in coil spring 4a (broken line in the figure) that passes through the inside of the protruding portion 75a of the main body side plate 3000, which is the rotation fulcrum 75, and conveys the waste toner from the cleaning device 61 to the waste toner cassette 1. Specifically, the waste toner discharge port 1000a of the intermediate transfer belt unit 1000 on the extension line of the screw 61g (on the front side in FIG. 2) and the waste toner inlet 1b of the waste toner cassette 1 are connected by a pipe 4, Waste toner is conveyed from the cleaning device 61 to the waste toner cassette 1 by the coil spring 4a. However, since the pipe 4 is attached to the upper housing 1060 side and rotates together with the opening and closing of the upper housing 1060, the pipe 4 is rotatable inside the protruding portion 75a and inside the waste toner inlet 1b. FIG. 5 shows the positional relationship between the cleaning device 61 and the waste toner cassette 1 and the waste toner inlet 1b. From the figure, it can be seen that the rotation fulcrum 75 and the waste toner inlet 1b are in the same position. The pipe 4 is positioned at the rotation fulcrum 75. Further, since the waste toner cassette 1 is movable in the left direction in FIG. 7 and the intermediate transfer belt unit 1000 is movable in the downward direction in FIG. 7, the cleaning cassette 220 and the waste toner cassette 1 are removed from the pipe 4. Each can be easily detached.

  As described above, the intermediate transfer belt unit 1000 is a type that does not include a waste toner container, and the divided cleaning device 61 and the waste toner cassette 1 are arranged in separate housings as in the conventional example. Although there are concerns about problems due to opening and closing (occurrence of toner leakage and toner scattering due to separation of the waste toner discharge port 1000a and the waste toner inlet 1b when the housing is opened), the pipe 4 passes through the rotation fulcrum 75 as described above. Therefore, there is no movement of the pipe 4 when the upper housing 1060 is opened and closed. Therefore, when the upper housing 1060 is opened and closed, the pipe 4 does not leave the waste toner discharge port 1000a and the waste toner inlet 1b, so that the problems of toner leakage and toner scattering are solved.

As shown in FIG. 5, in the intermediate transfer belt unit 1000 that does not include a waste toner storage unit, the waste toner cassette 1 is disposed in a lower casing 1050 that is positioned below the gravitational direction, and is positioned above the lower casing 1050. An intermediate transfer belt unit 1000 (cleaning device 61) is disposed in the upper housing 1060. In this embodiment, the waste toner cassette 1 is disposed and the position of the rotation fulcrum 75 provided on the lower casing 1050 on the lower side in the gravity direction is set as high as possible to the lower casing 1050, and the intermediate transfer belt unit 1000 (cleaning) The device 61) is arranged further above the pivot point 75. Since the pipe 4 connects the intermediate transfer belt unit 1000 (cleaning device 61) and the waste toner cassette 1 through the rotation fulcrum 75, the problem of toner leakage and toner scattering is solved, and smooth waste toner conveyance is possible. The capacity of the waste toner cassette 1 can be increased.
Further, in recent image forming apparatuses using an intermediate transfer member, a toner patch for forming an image on the intermediate transfer member for process control / drive system control rather than residual toner on the photosensitive member or the intermediate transfer member due to an improvement in transfer efficiency. The amount of toner mark cleaning is increasing.

Therefore, in this embodiment, the intermediate transfer belt unit 1000 is disposed in the upper housing 1060, the image stations 140 and 240 having the photoconductors 160 and 260, and the waste toner cassette 1 are disposed in the lower housing 1050, and the rotation fulcrum 75 is also provided. The intermediate transfer belt unit 1000 is positioned above the image stations 140 and 240 and the waste toner cassette 1 by making the upper side of the lower casing 1050 as high as possible. According to this configuration, the waste toner cassette 1 can be enlarged, and the waste toner inlet 1b into which the waste toner from the intermediate transfer belt unit 1000 having a large amount of cleaning can enter can be positioned upward. 1 can be delayed, and the replacement frequency of the waste toner container can be reduced.
The intermediate transfer belt unit 1000 (cleaning device 61) is disposed in the upper casing 1060, and the waste toner cassette 1 is disposed in the lower casing 1050. The upper casing 1060 opens and closes the lower casing 1050, and a pivot fulcrum 75 is provided. Therefore, the waste toner cassette 1 and the pipe 4 do not move as the casing is opened and closed. Therefore, it is possible to solve the problem of toner leakage and toner scattering when the casing is opened and closed.

FIG. 8 is a view showing another embodiment around the rotation fulcrum 75 of FIG.
A hollow sleeve shaft 75f is fixedly provided at the position of the pivot fulcrum 75 of the main body side plate 3000, and a hole 75h to be fitted to the outer periphery of the sleeve shaft 75f is provided in the side plate 5000 of the upper housing 1060. The rotation fulcrum 75 is formed by fitting them. If the same is applied to the opposite main body side plate 4000 side, the upper housing 1060 can be rotated with respect to the lower housing 1050. The sleeve shaft 75 f connects the waste toner inlet 1 b of the waste toner cassette 1 and the pipe 4, and the pipe 4 connects the sleeve shaft 75 f and the intermediate transfer belt unit 1000. The waste toner cassette 1 can be detached from the sleeve shaft 75f, but the pipe 4 is prevented from being detached from the sleeve shaft 75f. However, since the pipe 4 is attached to the upper casing 1060 side and rotates together with opening and closing of the upper casing 1060, the pipe 4 is rotatable inside the sleeve shaft 75f. Waste toner from the intermediate transfer belt unit 1000 passes through the pipe 4 by the coil spring 4a, passes through the sleeve shaft 75f, and is conveyed to the waste toner cassette 1. By using the sleeve shaft 75f as the rotation fulcrum 75, the reliability and durability of the opening and closing operation of the upper housing 1060 are improved, and the problems of toner leakage and toner scattering are solved.

FIG. 9 shows still another embodiment around the rotation fulcrum 75.
A hollow sleeve shaft 75c is fixed to the position of the pivot fulcrum 75 of the main body side plate 3000, and a hole 75e to be fitted to the outer periphery of the sleeve shaft 75c is provided in the side plate 5000. The rotation fulcrum 75 is formed by fitting them. If the same is applied to the opposite main body side plate 4000 side, the upper housing 1060 can be rotated with respect to the lower housing 1050. The pipe 4 passes through the inside of the sleeve shaft 75c, which is the rotation fulcrum 75, and connects the waste toner inlet 1b of the toner cassette 1 and the intermediate transfer belt unit 1000. The waste toner cassette 1 can be detached from the pipe 4. It has become. However, since the pipe 4 is attached to the upper housing 1060 side and rotates together with the opening and closing of the upper housing 1060, the pipe 4 is rotatable inside the sleeve shaft 75c and inside the waste toner inlet 1b. Waste toner from the intermediate transfer belt unit 1000 is conveyed to the waste toner cassette 1 through the pipe 4 by the coil spring 4a. By using the sleeve shaft 75c as the rotation fulcrum 75, the reliability and durability of the opening / closing operation of the upper housing 1060 are improved at a lower cost than in FIG. 8, and the problems of toner leakage and toner scattering are solved.
As described above, in this embodiment, the cleaning device 61 of the intermediate transfer belt unit 1000 and the waste toner cassette 1 are arranged in separate housings. However, the waste toner cassette 1 and the intermediate transfer belt unit 1000 are in the same housing, and the image station. Even in the case of an image forming apparatus having a configuration in which the cleaning cassettes 220 of 140 and 240 are arranged in separate housings (for example, an image forming apparatus in which the intermediate transfer belt unit 1000 and the image stations 140 and 240 of this embodiment are arranged upside down). The present invention is applicable. That is, the present invention is applicable to any image forming apparatus having a configuration in which the cleaning unit and the waste toner storage unit are arranged in different housings, regardless of what is to be cleaned.
In this embodiment, a two-station recording type color image forming apparatus using two photoconductors has been described. However, the present invention is not limited to this, and an image forming apparatus having one photoconductor or four image forming apparatuses. Can also be applied.

  In the embodiment shown in FIGS. 2 and 5, the cleaning unit of the intermediate transfer belt unit 1000 is disposed above the rotation fulcrum 75, and the cleaning units of the image stations 140 and 240 are arranged from the cleaning unit of the intermediate transfer belt unit 1000. It is arranged below. By arranging the cleaning unit in this way, the waste toner discharge port 1000a of the intermediate transfer belt unit 1000 is located above the rotation fulcrum 75, and the waste toner discharge port 220a of the image stations 140 and 240 is below the rotation fulcrum 75. It becomes.

As one of the reasons for such a configuration, as described above, there are a process control / drive system control toner patch formed on the intermediate transfer belt, and a countermeasure for increasing the amount of waste toner of the intermediate transfer belt by toner marks. That is, since the waste toner amount of the intermediate transfer belt is larger than that of the image station, it is necessary to increase the waste toner storage amount of the intermediate transfer belt unit 1000 more than that of the image stations 140 and 240.
This is because the intermediate transfer belt unit 1000 needs to be positioned at the top of the image forming apparatus, and the position of the waste toner inlet 1b of the waste toner cassette 1 needs to be as high as possible.

  Further, in recent image forming apparatuses, in order to meet the demand for higher image quality, not only the intermediate transfer belt as described above but also toner patches and toner marks are formed on the photosensitive member, and at the same time as the intermediate transfer belt. Some types of process control / drive system control have been seen even for photoreceptors. In the case of such an image forming apparatus, the shape / size and image forming frequency of toner patches and toner marks formed on the intermediate transfer belt and the photoconductor vary greatly depending on the specifications and concept of the image forming apparatus. Since the amount of waste toner on the belt and the photoconductor is different depending on the model, it cannot be clearly stated which is larger.

  Conventionally, the amount of waste toner could not be compared without actually making a measurement and actually measuring it. However, in recent years, if calculation / simulation technology that has made remarkable progress is used, the target image quality, output speed, etc. In addition, the amount of waste toner can be calculated with a certain degree of accuracy, and can be compared on the desk without actually measuring it.

  Therefore, as a procedure for designing the image forming apparatus, in the concept study stage, first, the amount of waste toner on the intermediate transfer belt and the photoreceptor is calculated / simulated, and an initial determination is made as to which amount of waste toner is greater. . Then, after performing a simple verification experiment for confirming whether the result is correct, the final judgment is made and the result is reflected in the layout.

  In other words, the cleaning unit with the larger amount of waste toner is arranged on the upper side in the direction of gravity with respect to the rotation fulcrum, and the cleaning unit with the smaller amount of waste toner is arranged on the lower side in the direction of gravity with respect to the cleaning unit with the larger amount of waste toner. Design layout so that As a result, an optimal layout of the image forming apparatus with a low replacement frequency of the waste toner cassette can be achieved.

Next, a case where the amount of waste toner on the intermediate transfer belt is larger and a case where the amount of waste toner on the photoreceptor is larger will be described.
The configuration in the case where the amount of waste toner on the intermediate transfer belt is larger is the same as that shown in FIGS.
An example of the configuration when the amount of waste toner on the photoconductor is larger is shown in FIG.
Briefly describing FIG. 10, the writing device 180 and the image stations 140 and 240 described later are disposed in the upper portion of the intermediate transfer belt unit 1000 in FIG. 2 described above.
In FIG. 2, the functional configuration and operation of the two-station image forming apparatus have been described in detail. Therefore, since FIG. 10 is the same two-station system, the diagram is simplified. Also, the devices and components mounted on the image forming apparatus are shared with the symbols in FIG. 2 if the names and functions are the same even if the shapes are somewhat different.

  The image forming apparatus shown in FIG. 10 is stacked in order from the lower part in the direction of gravity such that the transfer paper storage unit 70A and the paper feed roller 70B, the intermediate transfer belt unit 1000, image stations 140 and 240, fixing means 90, and writing device 180 described later. It is configured. Also, at the right end of the image forming apparatus shown in the figure, there is a substantially vertical sheet conveyance path constituted by registration rollers 96a and 96b, a transfer roller 98, and the like, and upward from the transfer sheet storage section 70A through the sheet feeding roller 70B. Furthermore, the paper transfer portion which is a contact portion between the transfer roller 98 and the roller 130 → the fixing portion by the fixing device 90 → the waste paper portion 99 extends.

The writing unit 180 exposes the photoconductors 160 and 260 according to image information from above with a semiconductor laser.
The latent image forming and developing means is composed of a photosensitive cassette, a cleaning cassette which is an example of a cleaning device, and three main cassettes and devices of the developing device, which are unitized by members supporting the developing device. The image station is configured. Two image stations similarly configured by similar members are arranged in parallel on the left and right, and the left side of the image forming apparatus shown in FIG. 10 is a first image station 140 and the right side is a second image station 240.

Similarly to FIG. 2, the unitized image stations 140 and 240 and the intermediate transfer belt unit 1000 are individually detachably attached to the apparatus main body, and the image stations 140 and 240, the writing unit 180, the fixing device are provided. 90 and the like are housed in an upper housing 1060 including a main body side plate, and an intermediate transfer belt unit 1000, a transfer paper housing portion 70A, and the like are housed in a lower housing 1050.
The upper housing 1060 opens in a crocodile shape with respect to the lower housing 1050 around the rotation fulcrum 75.

The relationship between the intermediate transfer belt unit 1000 and the waste toner cassette 1 will be briefly described with reference to FIG.
FIG. 11 is a schematic view of a part of the periphery of the cleaning device 61 of the intermediate transfer belt unit 1000 shown in FIG. 10 as viewed from above.
The intermediate transfer belt unit 1000 is supported by the lower housing 1050 by fitting a bearing 120a of a roller 120 that drives the belt 100 protruding from the side surface of the intermediate transfer belt unit 1000 into a receiving member C provided inside the main body side plate 3000. And is positioned with high accuracy.
In addition, a detachable waste toner cassette 1 for storing waste toner from the cleaning device 61 of the intermediate transfer belt unit 1000 is provided outside the main body side plate 3000 (lower housing 1050). The cleaning device 61 of the intermediate transfer belt unit 1000 and the waste toner cassette 1 are connected by a hollow pipe 4 to prevent toner leakage and toner scattering at the joint between them.
The pipe 4 is provided with a coil spring 4a (broken line in the figure) for conveying waste toner from the cleaning device 61 of the intermediate transfer belt unit 1000 to the waste toner cassette 1. The pipe 4 is slidable in the left-right direction on the paper surface, and the intermediate transfer belt unit 1000 and the waste toner cassette 1 can be individually attached to and detached from the pipe 4.

Next, the relationship between the cleaning cassettes 220 of the image stations 140 and 240 and the waste toner cassette 1 will be described.
FIG. 12 is a schematic view of a part of each cleaning cassette 220 of the image stations 140 and 240 shown in FIG. 10 as viewed from above. In order to make the drawing easy to see, cassettes, devices, and parts constituting the image stations 140 and 240 such as the developing devices 60 and 80 and the photosensitive members 160 and 260 other than the cleaning cassette 220 are omitted.

  The side plate 5000 is a member constituting the upper housing 1060. The main body side plate 3000 and the side plate 5000 of the lower housing 1050 form a rotation fulcrum 75 using a sleeve shaft 75c. The waste toner cassette 1 installed at a position outside the main body side plate 3000 and also outside the side plate 5000 and the two cleaning cassettes 220 of the image stations 140 and 240 are connected by a hollow pipe 2 and joined together. This prevents toner leakage and toner scattering.

The pipe 2 has a built-in coil spring 2a (broken line in the figure) that passes through the inside of the sleeve shaft 75c, which is a pivot fulcrum 75, and conveys waste toner from each cleaning cassette 220 to the waste toner cassette 1.
Specifically, the waste toner discharge port 220a (see also FIG. 20) of each cleaning cassette 220 on the extension line of the screw 210c (see FIG. 2) built in each cleaning cassette 220 (on the front side in FIG. 10). ) And a waste toner inlet 1a (see also FIG. 50) of the waste toner cassette 1 are connected by a pipe 2, and the waste toner is conveyed from each cleaning cassette 220 to the waste toner cassette 1 by a coil spring 2a.
The pipe 2 is attached to the upper housing 1060 side, and the pipe 2 can be rotated inside the sleeve shaft 75c and inside the waste toner inlet 1a. It is designed to rotate.
With this configuration, the pipe 2 is not separated from the waste toner discharge port 220a and the waste toner inlet 1a when the upper housing 1060 is opened and closed. Therefore, the problem of toner leakage and toner scattering from the waste toner cassette 1 and the cleaning cassette 220 when the upper housing 1060 is opened and closed is solved.
In this embodiment, as shown by the pipe 2 in FIGS. 10 and 12, the pipe is shared so that the waste toners from the cleaning cassettes 220 are collectively conveyed to the waste toner cassette 1. A separate pipe may be provided for each cleaning cassette 220. However, sharing a common pipe is advantageous in terms of saving space, reducing the number of parts, and simplifying the configuration.

  FIG. 13 shows the positional relationship between the cleaning device 61 of the intermediate transfer belt unit 1000 and the cleaning cassette 220 of the image stations 140 and 240, the position of the waste toner cassette 1, and the waste toner inlets 1b and 1a.

  A long hole 1c at the upper center of the waste toner cassette 1 is a grip for attaching and detaching. It can be seen from FIG. 13 that the rotation fulcrum 75 and the waste toner inlet 1a are at the same position. The pipe 2 is configured to pass through the rotation fulcrum 75. The cleaning cassette 220 and the waste toner cassette 1 can be easily detached from the pipe 2 individually.

  As described above, in this embodiment, the amount of waste toner on the photosensitive member and the amount of waste toner on the intermediate transfer member are compared, and the cleaning portion of the image carrier having the larger amount of waste toner is moved to the gravity with respect to the rotation fulcrum. The cleaning portion of the image carrier having the smaller amount of waste toner is disposed on the lower side in the gravity direction than the cleaning portion having the larger amount of waste toner. Further, in the case of having a plurality of photoconductors, if the photoconductor has a larger amount of waste toner than the intermediate transfer body, it is used for conveying waste toner from each cleaning unit of the photoconductor to a waste toner storage unit (waste toner cassette). Shared pipes.

As a recent trend, there is an image forming apparatus that employs a cleaningless means that does not have a cleaning unit in an image carrier due to demands for cost reduction, downsizing, environmental measures, and the like.
FIG. 14 shows a tandem type image forming apparatus using four photoconductors, and each photoconductor 160A employs a cleaningless means. The intermediate transfer belt 100 is provided with a cleaning unit 166A.
As a method for removing the residual toner on the photoconductor in the cleaning-less unit of the photoconductor, for example, a small amount of toner remaining on the photoconductor after the transfer is once taken in by a charging device 162A disposed around the photoconductor 160A. There is a method in which the electrostatic characteristics are changed and returned to the photoreceptor 160A again, and then the developing device 163A collects the toner and reuses it. When the cleaning-less means is adopted for the photoconductor 160A, since the waste toner is substantially zero, waste toner is generated, and only the waste toner of the belt 100 provided with the cleaning unit enters the waste toner cassette 1. It becomes. In order to increase the amount of waste toner stored in the belt 100 as much as possible, the cleaning unit of the belt 100 is positioned above the waste toner inlet 1b of the waste toner cassette 1 installed in the lower casing 1050, that is, above the rotation fulcrum 75. desirable.
This is because the waste toner cassette 1 can be enlarged and the waste toner inlet 1b of the waste toner cassette 1 can be positioned upward if the position of the cleaning portion of the belt 100 is located above the rotation fulcrum 75. is there.
Naturally, the cleaningless photoconductor 160 </ b> A is arranged below the intermediate transfer belt 100.

  FIG. 15 shows a tandem type image forming apparatus in which a belt 100 of an intermediate transfer member is provided with cleaningless means. Each photoconductor 160A is provided with a cleaning unit 164A. As a method of removing the residual toner on the belt 100 by the cleaning-less means of the belt 100, for example, a small amount of toner remaining on the belt 100 after the transfer is electrostatically discharged by a charging device 165A disposed around the intermediate transfer belt 100. There is a method in which the characteristics are changed and reversely transferred onto the photoconductor 160A, and then the toner is cleaned by the cleaning unit 164A of the photoconductor 160A and stored in the waste toner cassette 1.

When the belt 100 is provided with cleaningless means, the waste toner on the belt 100 uses the cleaning unit 164A of the photoconductor 160A, and the waste toner cassette 1 from the cleaning unit 164A of the photoconductor 160A together with the waste toner of the photoconductor 160A. to go into.
That is, the waste toner entering the waste toner cassette 1 is only from the photoconductor 160A provided with the cleaning unit.
Therefore, in order to delay the replacement timing of the waste toner cassette 1 and reduce the replacement frequency, it is necessary to increase the waste toner storage amount of the photoconductor 160A as much as possible. In order to increase the waste toner capacity of the photoconductor 160A as much as possible, the position of the cleaning portion of the photoconductor 160A is positioned above the waste toner inlet 1a of the waste toner cassette 1 installed in the lower housing 1050, that is, above the rotation fulcrum 75. It is desirable to make it.
This is because the waste toner cassette 1 can be enlarged if the position of the cleaning portion of the photoconductor 160A is positioned above the rotation fulcrum 75, and the position of the waste toner inlet 1a of the waste toner cassette 1 is set upward. Because you can. As a matter of course, the cleaningless belt 100 is arranged below the photoconductor 160A.

  As described above, in this embodiment, when either one of the photosensitive member and the intermediate transfer member employs a cleaningless unit, the cleaning unit of the image carrier on which the cleaning unit is provided is set with respect to the rotation fulcrum. The image carrier, which is disposed on the upper side in the gravity direction and employs the cleaning-less means, is disposed on the lower side in the gravity direction than the one provided with the cleaning unit.

  In the embodiments so far described, the relationship between the intermediate transfer belt and the photosensitive member is completely up and down in order to make the present invention easier to understand. For example, the positional relationship between the latent image carrier (photosensitive member) and the intermediate transfer member, which are image carriers, is not limited. For example, the present invention can be applied to an intermediate transfer belt such as RICOH IPSiO Color 8000 (registered trademark) or a configuration in which the photosensitive member is obliquely arranged.

[Effect]
<Claim 1>
Even if the cleaning unit and waste toner storage unit are arranged separately, the problem of toner leakage and toner scattering due to the opening and closing of the case can be solved, the transport path can be simplified, the device can be made compact, and smooth waste can be achieved . Toner conveyance and waste toner storage capacity can be increased .
<Claim 2 >
The problem of toner leakage and toner scattering can be solved, the waste toner full time can be delayed, and the replacement frequency of the waste toner storage unit can be reduced.
<Claim 3 >
The problem of toner leakage and toner scattering when the casing is opened and closed can be solved.
<Claim 4 >
Waste toner from the image carrier and / or the transfer body can be conveyed to the waste toner storage unit without problems of toner leakage and toner scattering.
<Claim 5 >
The reliability of the case opening / closing operation and the durability are improved, and the problem of occurrence of toner leakage and toner scattering is solved.
<Claim 4>
The cost and cost of the image forming apparatus according to the third aspect are improved, and the reliability and durability of the casing opening / closing operation are improved, and the problems of toner leakage and toner scattering are solved.
<Claim 5 >
It is possible to replace only the waste toner storage section whose replacement time has come.

<Claim 8 >
Toner leakage and toner scattering can be suppressed, the waste toner storage capacity of the larger amount of waste toner can be increased, and the replacement frequency of the waste toner storage section can be reduced.
<Claim 9 >
Toner leakage and toner scattering from the cleaning portion of the intermediate transfer member having a large amount of waste toner can be suppressed, the waste toner storage capacity of the intermediate transfer member can be increased, and the replacement frequency of the waste toner storage portion can be reduced.
<Claim 10 >
The toner leakage and toner scattering from the cleaning part of the latent image carrier (photoreceptor) with a large amount of waste toner can be suppressed, the waste toner storage capacity of the latent image carrier (photoreceptor) is increased, and the waste toner storage part The frequency of replacement can be reduced.
<Claim 11 >
Toner leakage and toner scattering can be suppressed, the waste toner storage capacity of the one provided with the cleaning unit can be increased, and the replacement frequency of the waste toner storage unit can be reduced.
<Claim 12 >
Toner leakage and toner scattering from the cleaning portion of the intermediate transfer member can be suppressed, the waste toner storage capacity of the intermediate transfer member can be increased, and the replacement frequency of the waste toner storage portion can be reduced.
<Claim 13 >
The toner leakage and toner scattering from the cleaning part of the latent image carrier (photoreceptor) can be suppressed, the waste toner storage capacity of the latent image carrier (photoreceptor) is increased, and the replacement frequency of the waste toner storage part is reduced. can do.
<Claim 14 >
Toner leakage and toner scattering can be suppressed, contributing to space saving of the image forming apparatus, reduction in the number of parts, and simplification of the configuration.

  The present invention can be used in an image forming apparatus such as a copying machine, a printer, and a facsimile.

1 is a conceptual diagram of an image forming apparatus as a premise of the present invention. It is a figure which shows the cross section of one Example to which the image forming apparatus of this invention is applied. FIG. 3 is a schematic view of the first image station 140 of FIG. 2 as viewed from above. FIG. 3 shows an enlarged view of the first image station 140 of FIG. 2. 2 is a front view of the waste toner cassette 1. FIG. It is an image when the main body housing is opened. FIG. 4 is a schematic image view of a part of the periphery of the cleaning device 61 of the intermediate transfer belt unit 1000 of FIG. 2 as viewed from above. It is a figure which shows the other Example of the rotation fulcrum 75 periphery of FIG. This is still another embodiment around the rotation fulcrum 75. FIG. 4 is a diagram illustrating an example of a configuration when the amount of waste toner on a photoconductor is larger. FIG. 11 is a schematic view of a part of the periphery of the cleaning device 61 of the intermediate transfer belt unit 1000 shown in FIG. 10 as viewed from above. It is the schematic which looked at a part of each cleaning cassette 220 of the image stations 140 and 240 shown in FIG. 10 from upper direction. FIG. 4 is a diagram showing the positional relationship between the cleaning device 61 of the intermediate transfer belt unit 1000 and the cleaning cassette 220 of the image stations 140 and 240, the position of the waste toner cassette 1, and the waste toner inlets 1b and 1a. 1 is a diagram illustrating a tandem type image forming apparatus using four photoconductors. FIG. 1 is a diagram showing a tandem type image forming apparatus in which a belt 100 of an intermediate transfer member is provided with cleaningless means.

Explanation of symbols

60, 80 Developing device 61a, 210a Cleaning blade 98 Transfer roller 100 Belt 120, 130 Roller 140 First image station 160, 260 Photosensitive member (image carrier)
180 Optical writing unit 190 Magenta developer 200 Cyan developer 240 Second image station 290 Yellow developer 300 Black developer 410, 420 Transfer brush

Claims (14)

An image carrier that carries a visible image of toner, a transfer unit that transfers the visible image of the image carrier to a medium, a first cleaning unit that collects toner remaining on the image carrier after transfer, An image forming apparatus comprising at least a waste toner storage unit that stores toner collected by the first cleaning unit,
A housing, which is a structure of the image forming apparatus, includes at least a main body housing and a sub-housing that can rotate about the rotation fulcrum with respect to the main body housing, and the first cleaning unit includes Waste toner that is disposed in one of the main body housing and the sub housing, the waste toner container is disposed in the other housing, and reaches the waste toner container from the first cleaning unit. The conveyance path has a conveyance path portion that passes through the rotation fulcrum position of the casing, the image forming apparatus is configured by at least a plurality of casings, and the waste toner container is disposed in the casing located on the lower side in the gravitational direction. The first cleaning unit is disposed in a case located above the case in the gravity direction or a case having a portion extending in the upper direction of the gravity direction, and the direction of gravity with respect to the rotation fulcrum of the case The waste toner container is placed on the lower side, and the upper side in the direction of gravity The first cleaning unit is disposed, the waste toner storage unit includes a first waste toner inlet coaxial with the rotation fulcrum at a rotation fulcrum position, and the first cleaning unit includes a waste toner discharge port. The toner inlet is located below the waste toner discharge port in the direction of gravity, and the waste toner transfer path includes a toner transfer pipe that connects the waste toner discharge port and the first waste toner inlet. Image forming apparatus. The image forming apparatus according to claim 1.
The housing side on which the cleaning unit is installed has a second cleaning unit with a smaller amount of waste toner than the first cleaning unit, and the cleaning unit with the larger amount of waste toner discharged from each cleaning unit. And the first cleaning unit is disposed on the housing located on the upper side in the gravity direction than the housing on which the waste toner storage unit is disposed, or on the housing side having a portion extending on the upper side in the gravity direction. The storage unit includes a second waste toner inlet through which waste toner discharged from the second cleaning unit is conveyed, and the second waste toner inlet is lower than the first waste toner in the direction of gravity. an image forming apparatus comprising the provided Turkey on. The image forming apparatus 請 Motomeko 1 or 2,
An image forming apparatus, wherein a housing in which the cleaning unit is disposed is a rotation side, and a housing in which a waste toner storage unit is disposed is a non-moving side. The image forming apparatus 請 Motomeko 1 or 2,
A latent image carrier on which an electrostatic latent image is formed; and a developing unit that develops the electrostatic latent image into a visible image using toner, the image carrier on the latent image carrier An image forming apparatus, being an intermediate transfer member to which a visible image is transferred, wherein the visible image transferred to the image carrier is transferred to a recording medium. The image forming apparatus 請 Motomeko 1 or 2,
An image forming apparatus characterized in that a rotation fulcrum of the housing is constituted by a hollow sleeve shaft, and waste toner passes through the sleeve shaft to reach a waste toner storage portion. The image forming apparatus 請 Motomeko 1 or 2,
The rotation fulcrum of the housing is constituted by a hollow sleeve shaft, a pipe for toner conveyance is provided in the sleeve shaft, and waste toner passes from the cleaning section to the waste toner storage section. Image forming apparatus. The image forming apparatus 請 Motomeko 1 or 2,
An image forming apparatus, wherein the waste toner container is detachable from the image forming apparatus. The image forming apparatus 請 Motomeko 1 or 2,
Each of the image bearing members includes a latent image bearing member and an intermediate transfer member each having a cleaning unit, and the image bearing member having the larger amount of the waste toner amount of the latent image bearing member and the waste toner amount of the intermediate transfer member. A cleaning unit for the body is disposed above the rotation fulcrum of the housing in the direction of gravity, and the cleaning unit for the image carrier having the smaller amount of waste toner is used to clean the image carrier having the larger amount of waste toner. An image forming apparatus, wherein the image forming apparatus is disposed below the gravitational direction. The image forming apparatus according to claim 1 or 2 ,
An image bearing member with the larger amount of waste toner is a medium between the transfer member, arranged in the direction of gravity above the cleaning section of the intermediate transfer member with respect to the pivot point of the casing, the waste toner of the intermediate transfer body And an image forming apparatus, wherein the cleaning unit for the latent image carrier is disposed below the cleaning unit for the intermediate transfer member in the direction of gravity. . The image forming apparatus according to claim 1 or 2 ,
Direction with many waste toner amount is said latent image bearing member, disposed a cleaning unit of the latent image bearing member in the direction of gravity above with respect to the rotation fulcrum of the casing, the waste toner of the latent image bearing member than once An image forming apparatus configured to pass through a moving fulcrum to reach a waste toner storage unit, and the cleaning unit for the intermediate transfer member is disposed below the cleaning unit for the latent image carrier in the direction of gravity. The image forming apparatus according to any one of 請 Motomeko 1 to 10,
When either one of the two image bearing member of a latent image carrier and middle-transfer member having a cleaning-less means, the cleaning portion of the image bearing member who provided the cleaning unit to the pivot point of the housing Te was placed in the gravity direction upward and towards the image bearing member which is provided with the cleaning-less means, wherein arranged in the gravity direction lower side of the image bearing member towards having a cleaning unit, having at least one cleaning unit An image forming apparatus comprising two image carriers, a latent image carrier and an intermediate transfer member. The image forming apparatus according to claim 11.
When the intermediate transfer member has a cleaning portion and the latent image carrier is a cleaning-less means, the cleaning portion of the intermediate transfer member is disposed above the rotation fulcrum of the housing in the gravity direction, An image forming apparatus characterized in that the waste toner of the intermediate transfer member passes through a rotation fulcrum and reaches a waste toner container, and the latent image carrier is disposed below the intermediate transfer member in the gravitational direction. . The image forming apparatus according to claim 11.
When the latent image carrier has a cleaning portion and the intermediate transfer member is a cleaning-less means, the cleaning portion of the latent image carrier is disposed above the rotation fulcrum of the housing in the gravity direction, An image characterized in that the waste toner on the latent image carrier passes through a rotation fulcrum and reaches a waste toner container, and the intermediate transfer member is disposed below the latent image carrier in the direction of gravity. Forming equipment. The image forming apparatus according to claim 1,
A plurality of latent image carriers, each of which has a cleaning unit, and waste toner discharged from the cleaning unit of each latent image carrier passes through a common waste toner conveyance path to be a waste toner. An image forming apparatus configured to reach a storage unit.

Images