Abstract:
A disposal cartridge for use in an image forming apparatus includes a sheet and a roller. An area of the sheet is at least equal to an area of the entire circumferential surface of the roller. The sheet is detachably bonded to an entire circumferential surface of the roller. The roller attracts toner and is detachably and rotatably mounted on the disposal cartridge.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a disposal cartridge for use in an image forming apparatus, and more particularly to a disposal cartridge for use in an image forming apparatus with a relatively-low-cost recyclable toner-carrying roller. 
     2. Discussion of the Background 
     Designing reusable components for office machines, including image forming apparatuses such as copying machines, facsimile machines, and so forth, has become an issue in response to a recent rising tide of a recycling movement. For example, many image forming apparatuses use a disposal cartridge which typically includes a toner cartridge and a cleaning unit. Such a disposal cartridge employs rubber-made rollers, including a magnet roller for use in a cleaning operation. These rubber-made rollers have a nature of having deposits of toner lodged on surfaces thereof after a long usage. The lodged deposits of toner are generally referred to as a toner-filming problem or toner-offset problem. As a result of this toner-filming problem, at the time the rubber-made rollers are disposed of, the rubber-made rollers will be subjected to a severe cleaning process if they are, or were required to be made, reusable. 
     A widely-known technique for solving such a problem of the rubber-made toner carrying rollers is to coat a surface of such rollers with an agent, or a tube, having a good quality of separativeness. However, this technique adversely affects the manufacturing cost of such rollers. One reason is a relatively high material cost of the agent or the tube which has a good quality of separativeness. Another reason is a relatively complex manufacturing process of the above-mentioned technique. 
     SUMMARY OF THE INVENTION 
     Accordingly, an object of the present invention is to provide a novel disposal cartridge which includes a relatively low cost recyclable toner-carrying roller for use in an image forming apparatus. 
     Another object of the present invention is to provide a novel method of manufacturing a recyclable toner-carrying roller at a relatively low cost. 
     To achieve these and other objects, a novel disposal cartridge of the present invention for use in an image forming apparatus includes a sheet and a roller. In one embodiment, an area of the sheet is equal to an area of an entire circumferential surface of the roller. The sheet is detachably bonded to the entire circumferential surface of the roller. The roller attracts toner and is detachably and rotatably mounted on the disposal cartridge. 
     The sheet may have one adhesive surface. The area of the sheet may also be greater than the area of the entire circumferential surface of the roller, and an edge portion of a first end of the sheet may ride on an edge portion of an opposite end of the sheet. The edge portion of the first end of the sheet which rides on the edge portion of the opposite end of the sheet may be free or bonded to a surface of the edge portion of the opposite end of the sheet. The sheet may be made of polyethylene-terephthalate. 
     Also, to achieve the above-mentioned and other objects, a method of manufacturing a disposal cartridge for use in an image forming apparatus includes the steps of providing a roller that attracts toner and providing a sheet that has a surface having an area equal to an area of an entire circumferential surface of the roller. Further, the method includes the steps of detachably bonding the sheet to the entire circumferential surface of the roller, and detachably and rotatably mounting the roller on the disposal cartridge. 
     Other objects, features, and advantages of the present invention will become apparent from the following detailed description when read in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the present invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: 
     FIG. 1 is a schematic diagram for explaining a primary part of an image forming apparatus which includes a magnet roller according to an embodiment of the present invention; 
     FIGS. 2A and 2B are illustrations for explaining a sheet included in the magnet roller of FIG. 1; 
     FIGS. 3A and 3B are illustrations for explaining a way that the sheet of FIGS. 2A and 2B wraps around the magnet roller of FIG. 1; 
     FIG. 4 is an illustration for explaining another way that the sheet of FIGS. 2A and 2B wraps around the magnet roller of FIG. 1; and 
     FIG. 5 is an illustration for explaining still another way that the sheet of FIGS. 2A and 2B wraps around the magnet roller of FIG.  1 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In describing preferred embodiments of the present invention illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the present invention is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents which operate in a similar manner. 
     Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views, and more particularly to FIG. 1 thereof, a primary part of an image forming apparatus (e.g., copying machine) is illustrated as an exemplary embodiment of the present invention. The primary part of the image forming apparatus of FIG. 1 includes a photoconductive belt  1  and a plurality of rollers  2  which support and drive the photoconductive belt  1 . The photoconductive belt  1  driven by the rollers  2  rotates in the direction indicated by an arrow, as shown in FIG.  1 . The primary part of the image forming apparatus of FIG. 1 further includes a CTM (cleaner and toner magazine)  3  which includes a toner supply unit  4  and a cleaning unit  5  in one unit. The primary part of the image forming apparatus of FIG. 1 further includes a quenching unit  6 , a charger  7 , a development unit  8  which includes a development roller  9 , and a transfer unit  10 . 
     The toner supply unit  4  of the CTM  3  and the development unit  8  are connected with each other by a toner supply duct  11 . The toner supply unit  4  internally includes a toner agitator  12  for agitating toner and a toner conveyer  13  for conveying toner. The cleaning unit  5  of the CTM  3  includes a toner collecting chamber  14 , a cleaning blade  15 , a magnet roller  16 , and a scraper  17 . The toner collecting chamber  14  has an opening  14   a  through which a top edge of the cleaning blade  15  protrudes to an outside of the cleaning unit  5 . The magnet roller  16  is a toner carrying member which includes a sheet  18  wrapping around the rotating t surface thereof, which is explained in further detail below. In FIG. 1, letters P and T indicate a transfer paper and toner, respectively. The transfer paper P receives a toner image on a surface thereof from the photoconductive belt  1  by an image transfer operation from the transfer unit  10 . The toner T remains on the surface of the photoconductive belt  1  after the image transfer operation. 
     Such an image forming apparatus of FIG. 1 having the above-described primary part performs a known image forming operation which is not described herein. The following description is directed to a portion of the image forming operation related to the present invention. 
     After a toner image is transferred onto the transfer paper P from the photoconductive belt  1  with the transfer unit  10 , the cleaning blade  15  scrapes the surface of the photoconductive belt  1  to remove toner T remaining on the photoconductive belt  1 . The toner T which is removed from the photoconductive belt  1  is attracted to the magnet roller  16 , which is conveyed in the rotational direction A. Then, the conveyed toner is scraped off from the magnet roller  16  by the scraper  17  which makes contact with the magnet roller  16 . After being scraped off from the magnet roller  16 , the toner is held inside the toner collecting chamber  14 . Thus, the toner T which remains on the photoconductive belt  1  is collected into the toner collecting chamber  14 . 
     The CTM  3  which includes the above-described toner collecting mechanism is replaced when the toner supply unit  4  has no fresh toner left therein and/or when the toner collecting chamber  14  is filled with the collected toner. Since the CTM  3  includes several recyclable components, including the magnet roller  16 , such recyclable components are removed from the used CTM  3  to be subjected to a reconditioning process for reuse. 
     During the reconditioning process, the magnet roller  16  is removed from the CTM  3 . Then, the sheet  18  is removed from the surface of the magnet roller  16 . At this time, the sheet  18  may have deposits of the collected toner lodged on a surface thereof. On the other hand, after the removal of the sheet  18 , the magnet roller  16  has a fresh surface having no lodged deposits of the collected toner. Therefore, such a magnet roller  16  may be used again either as it is or by having a replacement sheet  18  detachably bonded onto the surface of the magnet roller  16 . 
     As illustrated in FIG.  2 A and FIG. 2B, the above-described sheet  18  includes a base sheet  20  which is made of polyethylene-terephthalate (FTP), for example, and on which an adhesive agent  21  is coated. One way that such a sheet  18  is bonded around the magnet roller  16  is illustrated in FIGS. 3A and 3B. As illustrated in FIG. 3A, the bonding starts from a leading edge  18   a  of the sheet  18  with the adhesive agent  21  facing the surface of the magnet roller  16 . At the end of bonding, as illustrated in FIG. 3B, a trailing edge  18   b  of the sheet  18  makes contact with the leading edge  18   a  without any embossment caused by the trailing edge  18   b  riding on the leading edge  18   a . In this way, the magnet roller  16  can be wrapped with the replaceable sheet  18  around the surface thereof for an easy recycling operation. 
     Alternatively, the trailing edge  18   b  of the sheet  18  can be ended by riding on the leading edge  18   a , as illustrated in FIG.  4 . In this case, a riding portion of the trailing edge  18   b  onto the leading edge  18   a  forms a step  22 , so that the sheet  18  can easily be removed by being peeled off from the step  22 . 
     Furthermore, the step  22  on the leading edge  18   a  may alternatively be free from the surface of the sheet  18  by configuring the step  22  to have no coating of the adhesive agent  21 , as illustrated in FIG. 5, so that the sheet  18  can easily be removed by being peeled off from the step  22 , which step  22  can be easily pinched as it is free. 
     As mentioned above, the magnet roller  16  is described as only one exemplary recyclable component that carries toner in the image forming apparatus. The present invention can be applied to other toner carrying components. 
     In addition, the material of the sheet  18  is not limited to the above-described example, and any suitable material for which the toner carrying components do not reduce the characteristics and functions thereof can be used. 
     Also, the present invention can be applied to an image forming apparatus which uses a so-called process cartridge which unifies the photoconductive belt  1  and the CTM  3  into one unit. 
     Obviously, numerous additional modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described herein. 
     This document is based on Japanese patent application No. JPAP10-001599 filed in the Japanese Patent Office on Jan. 7, 1998, the entire contents of which are hereby incorporated by reference.