Patent Publication Number: US-8995871-B2

Title: Powder collecting device

Description:
This application is based on Japanese Patent Application No. 2011-202492 filed on Sep. 16, 2011, the content of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a powder collecting device, particularly to a powder collecting device for collecting powder, such as toner, a developer, waste toner and a waste developer, in an electrophotographic copier or printer. 
     2. Description of Related Art 
     Generally, an electrophotographic image forming apparatus is provided with a waste powder collecting device for collecting waste toner removed from an image support member, such as a photoreceptor, or for collecting a waste developer removed from a developing device. In this type of collecting device, as shown by  FIG. 8 , waste toner or a waste developer is fed in a conveyer pipe  105  in a direction shown by arrow B by a conveyer screw  131 , and the waste toner or the waste developer is dropped through an opening  132  made at an end of the pipe  105  to be received in a specified position of a container  120 . 
     The container  120  is mountable in and dismountable from a body of an image forming apparatus. When the container  120  is mounted in the body of the image forming apparatus, an end of the conveyer pipe  105  is inserted in the container  120 . An elastic sealing member  125  as shown by  FIG. 9  is attached to an open end of the container  120  through which the end of the conveyer pipe  105  is inserted. Cuts  126  are radially made in the sealing member  125 , whereby tongue-like flaps  127   a  and  127   b  are formed. When the end of the conveyer pipe  105  is inserted in the container  120 , as shown in  FIG. 8 , the flaps  127   a  and  127   b  are bent by the end of the pipe  105 , and when the container  120  is dismounted from the body of the image forming apparatus, as shown by  FIG. 9 , the sealing member  125  returns to its original state to close the open end of the container  120 . 
     Since the flaps  127   a  and  127   b  are formed by the cuts  126  made radially from the axis of the conveyer pipe  105 , the upper flaps  127   b  and the lower flaps  127   a  are relatively long. Especially the lower flaps  127   a  extend to the opening  132 , and therefore, waste toner T adheres to the tips of the lower flaps  127   a . When the container  120  is dismounted from the body of the container  120 , the lower flaps  127   a  return to the upstanding states, and in this moment, the waste toner T comes off from the tips of the flaps  127   a  and begrimes the inside of the apparatus, the floor and/or the user&#39;s hand. As the container  120  is mounted in and dismounted from the body of the image forming apparatus, the tips of the lower flaps  127   a  may be caught between the opening  132  of the pipe  105  and a shutter  133 , and may be torn. Additionally, in order to comply with a demand for downsizing of the whole image forming apparatus, the space for insertion of the conveyer pipe  105  into the container  120  needs to be reduced. Accordingly, the tips of the lower flaps  127   a  may cover a large part of the opening  132 , thereby obstructing the drop of the waste toner T and increasing the amount of waste toner T adhering to the lower flaps  127   a.    
     A sealing member for a toner container disclosed by Japanese Patent Laid-Open Publication No. 2010-085458 has cuts in different places on the outer surface and on the inner surface of the sealing member so as to achieve excellent sealing performance. This sealing member certainly has improved sealing performance, but this sealing member does not solve the problem that toner adheres to flaps of the sealing member, thereby causing the other components to be begrimed. 
     SUMMARY OF THE INVENTION 
     An aspect of the present invention relates to a powder collecting device for conveying at least one of toner, a developer, waste toner and a waste developer in a conveyance pipe in one direction and for dropping the at least one of toner, a developer, waste toner and a waste developer into a container through an opening made at one end of the conveyance pipe, and in the powder collecting device according to an embodiment of the present invention, the container is mountable in a body of an image forming apparatus such that the one end of the conveyance pipe is inserted in the container, and the container is dismountable from the body of the image forming apparatus, an elastic sealing member, which has a larger area than a cross-sectional area of the one end of the conveyance pipe, is attached to a portion of the container through which the one end of the conveyance pipe is inserted into the container, and a plurality of cuts are made in the sealing member such that the sealing member has a plurality of flaps including at least a flap located in an upper side and a flap located in a lower side, the flap located in the lower side having an elastically deformable portion that is shorter than that of the flap located in the upper side. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other objects and features of the present invention will be apparent from the following description with reference to the accompanying drawings, in which: 
         FIG. 1  is a schematic view of a main part of an image forming apparatus; 
         FIG. 2  is a front view of a waste powder collecting device; 
         FIG. 3  is a sectional view of the waste powder collecting device taken along a line X-X in  FIG. 2 ; 
         FIG. 4  is a perspective view of an end portion of a conveyer pipe; 
         FIG. 5  is an enlarged sectional view of a main part of the waste powder collecting device; 
         FIG. 6   a  is a sectional view of the conveyer pipe;  FIGS. 6   b  and  6   c  are front views of a sealing member showing cuts made thereon; 
         FIGS. 7   a  and  7   b  are front views of a sealing member showing cuts made thereon; 
         FIG. 8  is an enlarged sectional view of a main part of a conventional waste powder collecting device; and 
         FIG. 9  is a front view of a conventional sealing member showing cuts made therein. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A powder collecting device according to an embodiment will be hereinafter described with reference to the drawings. 
     An image forming apparatus shown by  FIG. 1  is a tandem-type color image forming apparatus. In the color image forming apparatus, image formation units  1 , each of which includes a photosensitive drum  2 , are arranged side by side, and toner images formed on the respective photosensitive drums  2  are transferred onto an intermediate transfer belt  10  that rotates in a direction shown by arrow A to be combined into a full-color image (primary transfer). Thereafter, the full-color image is transferred onto a sheet (not shown) by a secondary transfer member  15  (secondary transfer). In  FIG. 1 , the reference numbers provided with alphabets “y”, “m”, “c” and “k” denote members in association with image formation of yellow, magenta, cyan and black, respectively. 
     Each of the image formation units  1  is mainly composed of a photosensitive drum  2  and a developing device  3 . Waste toner removed from the photosensitive drum  2  is conveyed to a container  20  as shown by  FIG. 2  through a pipe  4 , and a waste developer including waste toner and carriers removed from the developing device  3  are conveyed to the container  20  through a pipe  5 . In the container  20 , waste powder conveyed thereto is collected in a central part  20   a  through paths shown by dotted lines, and a volume sensor (not shown) detects the volume of the collected waste powder. The structure for the conveyance of waste powder inside the container  20  is similar to the structure disclosed by Japanese Patent Laid-Open Publication No. 2010-145812. 
     Further, toner bottles  16  containing toner are arranged above the intermediate transfer belt  10 . Residual toner on the intermediate transfer belt  10  is removed by a cleaning device  11 , and the waste toner removed therefrom is collected in the container  20  by a collecting mechanism that is basically of the same structure as described below. A description of a route used for collection of waste toner from the intermediate transfer belt  10  is omitted. 
     The container  20 , as shown in  FIG. 3 , is mountable in a body of the image forming apparatus such that one end of the pipe  4  can be inserted therein, and the container  20  has eight holes for receiving end portions of the eight pipes  4  and  5  shown in  FIG. 1 . As shown by  FIGS. 3 and 4 , a screw  31  is provided in the pipe  4  and is driven to rotate in one direction. With the rotation of the screw  31 , waste toner is conveyed in a direction shown by arrow B toward the end inserted in the container  20 . The pipe  4  has an opening  32  in the inserted end portion at the bottom, and a shutter  33  is provided to cover the opening  32  and is pushed by a spring (not shown) in the direction of arrow B. When the container  20  is mounted in the body of the image forming apparatus, the shutter  33  is stopped by a wall  20   b  of the container  20 , thereby uncovering the opening  32 . When the container  20  is dismounted from the body of the image forming apparatus, the shutter  33  is revealed from the wall  20   b , thereby covering the opening  32 .  FIG. 4  shows a state where the shutter  33  uncovers the opening  32 . 
     The holes of the container  20  are covered with sealing members  25 . The sealing members  25  are elastic sheets, and sponge or foamable resin is suited to be used as the material of the sealing members  25 .  FIG. 6   a  shows a cross section of the pipe  4 .  FIGS. 6   b ,  6   c ,  7   a  and  7   b  show the positional relation between the cross-section of the pipe  4  (the dotted circle showing the internal wall of the pipe  4 ) and the sealing member  25 . Specifically, a plurality of cuts  26  is made in the sealing member  25  such that a plurality of upper and lower tongue-like flaps  27   a  and  27   b  can be formed and such that elastically deformable portions of the lower flaps  27   a  are shorter than those of the upper flaps  27   b . That is, the cuts  26  intersect with each other at a point P located below the center of the circle Q of the cross-section of the pipe  4 . The cuts  26  may be made in various ways, and in other words, the flaps  27   a  and  27   b  may be made into various shapes.  FIGS. 6   b ,  6   c ,  7   a  and  7   b  show typical shapes of the flaps  27   a  and  27   b.    
     When the end portion of the pipe  4  is inserted in the container  20 , as shown by  FIG. 5 , the flaps  27   a  and  27   b  of the sealing member  25  are bent by the end portion of the pipe  4 . When the container  20  is dismounted from the body of the image forming apparatus, the flaps  27   a  and  27   b  return to a flat state to cover the hole (where the pipe  4  is inserted) of the container  20 . 
     Since the lower flaps  27   a  have short elastic-deformable portions, the tips of the lower flaps  27   a  are stopped by the lower surface of the pipe  4  and do not reach the opening  32 . Therefore, in the state shown by  FIG. 5 , there is no possibility that waste powder may adhere to the lower flaps  27   a . Accordingly, when the container  20  is dismounted from the body of the apparatus, that is, when the lower flaps  27   a  return to the sealing positions, it never occurs that waste powder drops out of the container  20 . Further, there is no fear that the lower flaps  27   a  may block the opening  32  of the pipe  4  and may be caught between the opening  32  and the shutter  33 . 
     The cuts  26  made in the sealing member  25  may be linear as shown by  FIGS. 7   a  and  7   b , or alternatively may include an arc-like cut as shown by  FIGS. 6   b  and  6   c . Especially when an arc-like cut  26  along the cross-section of the pipe  4  is made in the sealing member  25 , a spill of waste powder can be effectively prevented without causing degradation of the sealing performance. 
     The present invention provides not only the waste powder collecting device according to the embodiment described above but also various modified devices including the gist of the present invention. 
     Especially the electrophotographic image formation units may be of an arbitrary structure, and the details of the container and the details of the shape of the sealing member may be designed arbitrarily. Further, the present invention is applicable not only to a collecting device for collecting waste toner and/or a waste developer but also to a supply device for supplying toner and/or a developer to a developer bottle. 
     Although the present invention has been described in connection with the preferred embodiment, it is to be noted that various changes and modifications are possible for those who are skilled in the art. Such changes and modifications are to be understood as being within the scope of the present invention.