Patent Publication Number: US-7899370-B2

Title: Toner container

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. 119 to Japanese Patent Application No. 2008-128759, filed on May 15, 2008, which application is hereby incorporated by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a toner container that is removably provided in an image forming device. 
     2. Description of the Related Art 
     A conventional facsimile machine, copier, printer, or the like, includes an image forming device, and toner supplied to a developing unit of the image forming device is contained in a toner container. The toner container has a toner supplying port arranged to supply the toner. The toner supplying port is covered by an openable and closable cover. The toner container is removably provided to a toner hopper. 
     The conventional art discloses, for example, a toner container provided with a cylindrical cover which is attached thereto and reciprocated along an axial direction of a cylindrical removing portion. In such a conventional configuration, when the toner container is attached to the toner hopper the toner supplying port opens, and when the toner container is removed from the toner hopper, the toner supplying port closes. 
     When removing the toner container from the toner hopper, the toner may leak from the toner supplying port and soil the inside of a device body. Therefore, it is necessary to prevent toner leakage when removing the toner container from the toner hopper. However, in the above conventional toner container, since the cover moves linearly with respect to the removing portion, the toner supplying port cannot be closed without leaking the toner that remains around the toner supplying port. In particular, in a second-half operation of closing the cover, the cover pushes out the toner that remains in the vicinity of the toner supplying port. 
     SUMMARY OF THE INVENTION 
     In order to overcome the problems described above, preferred embodiments of the present invention provide a toner container that reduces toner leakage at the time of removing the toner container from a toner hopper. 
     According to a preferred embodiment of the present invention, a toner container includes a cylindrical supplying pipe, a cylindrical cover, and a cam mechanism. The supplying pipe has a toner opening port on a side surface thereof. The cover is attached to the supplying pipe and has a cover opening port on a side surface thereof. The cam mechanism is provided to the supplying pipe and the cover to reciprocate the cover between an opening position where the toner opening port and the cover opening port match to each other and a closing position where the toner opening port is closed by the cover. The closing position is in a skewed position with respect to the opening position. 
     In the toner container according to another preferred embodiment of the present invention, the cam mechanism includes a plurality of supplying pipe side cams arranged on an outer circumferential surface of the supplying pipe in a circumferential direction and a plurality of cover side cams arranged on an inner circumferential surface of the cover in a circumferential direction to engage with the respective supplying pipe side cams. 
     According to another preferred embodiment of the present invention, the toner container includes an elastic body arranged to bias the cover towards the closing position. 
     The advantages of various preferred embodiments of the present invention will now be described. 
     Since the cover is reciprocated by the cam mechanism between the opening position and the closing position, which is skewed with respect to the opening position, when closing the toner supplying port, the cover moves from the opening position to the closing position while spirally rotating. Thus, the cover can close the toner opening port while scooping up the toner remained around the toner supplying port. As a result, toner leakage that may occur when the toner container is removed from the toner hopper can be reduced. 
     The cam mechanism may preferably have a simple shape and configuration. Moreover, by providing two cams, the cover can reliably be reciprocated between the opening position and the closing position. 
     After the toner supplying port is closed, the toner supplying port will remain steadily closed due to a biasing force of the elastic body. Therefore, the toner leakage can be reliably prevented even after the toner container is removed from the toner hopper. 
     Other features, elements, processes, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the present invention with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view illustrating a state in which a developing unit, a toner hopper, and a toner container of an image forming device according to a preferred embodiment of the present invention are connected with each other. 
         FIG. 2  is a side view illustrating a portion of a supplying pipe in a sectional view according to a preferred embodiment of the present invention. 
         FIGS. 3A ,  3 B, and  3 C are perspective views of portions schematically illustrating a cover opening and closing operation according to a preferred embodiment of the present invention. 
         FIGS. 4A and 4B  are side views of portions schematically illustrating a state in which the toner container is attached to the toner hopper according to a preferred embodiment of the present invention. 
         FIGS. 5A and 5B  are sectional views illustrating a comparison between a cover according to a preferred embodiment of the present invention and a cover according to a conventional art. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Preferred embodiments of the present invention will be described.  FIG. 1  is a perspective view illustrating a state in which a developing unit  2 , a toner hopper  5 , and a toner cartridge  10  of an image forming device according to a preferred embodiment of the present invention are connected with each other.  FIG. 2  is a side view illustrating a portion of a supplying pipe  20  in a sectional view.  FIG. 3  is a perspective view of portions schematically illustrating an operation of opening and closing a cover  30 .  FIGS. 4A and 4B  are side views of portions schematically illustrating a state in which the toner cartridge  10  is attached to the toner hopper  5 .  FIGS. 5A and 5B  are sectional views illustrating a comparison between the cover of the present preferred embodiment ( FIG. 5B ) and a cover  130  of a conventional art ( FIG. 5A ). 
     A configuration of the developing unit  2  including the toner cartridge  10  provided as a toner container according to a preferred embodiment of the present invention will now be described. The toner cartridge  10  is removably attached to the image forming device of a printer. The image forming device according to a preferred embodiment of the present invention may be a multifunctional peripheral, such as a copier, or a facsimile machine, for example. It may have other functions in addition to a printer function as long as the device has the printer function. 
     As illustrated in  FIG. 1 , a photoconductive drum  3  is rotatably provided to the developing unit  2 . Toner supplied to the developing unit  2  is recorded on an outer circumferential surface of a not-illustrated developing roller by the developing roller and a not-illustrated supplying roller, etc. Then, the toner is adhered to an electrostatic latent image formed on an outer circumferential surface of the photoconductive drum  3  and forms an image. Further, a paper is transported between the photoconductive drum  3  and a transfer roller opposing the photoconductive drum  3 . When a transfer bias is applied to the transfer roller, the toner moves to a surface side of the paper, and a toner image is transferred to the paper. The paper having the transferred toner image is fixed by being heated and pressed by a fixing unit, and an image is formed on the surface of the paper. 
     The toner cartridge  10  is connected to the developing unit  2 . The toner cartridge  10  includes an unused-toner containing unit  11  arranged to contain unused toner and a waste-toner collecting unit  12  arranged to collect the used waste toner. 
     The unused-toner containing unit  11  is connected to the toner hopper  5  via the supplying pipe  20 . The toner hopper  5  is a container which can store a prescribed amount of toner. The unused toner in the toner cartridge  10  is transported from the unused-toner containing unit  11  to the toner hopper  5  through the supplying pipe  20 . 
     The toner hopper  5  is connected to the developing unit  2  via a pipe  6 . The unused toner stored in the toner hopper  5  is transported from the toner hopper  5  to the developing unit  2  through the pipe  6 . 
     The waste-toner containing unit  12  is connected with the developing unit  2  via a pipe  7 . The waste toner scraped from the outer circumferential surface of the photoconductive drum  3  by a photosensitive brush is transported from the developing unit  2  to the waste-toner containing unit  12  via the pipe  7 . 
     The supplying pipe  20  will now be described in detail. As illustrated in  FIG. 2 , a cover  30  is attached to a leading edge portion of the supplying pipe  20  through the intermediary of a spring  40  provided as an elastic body. It should be noted that it is also possible to use any other type of elastic body, if so desired. In order to simplify the description,  FIG. 2  separately illustrates the supplying pipe  20 , the spring  40 , and the cover  30 . 
     The supplying pipe  20  preferably has a cylindrical shape and includes inside the pipe  20  a screw member  21  that defines a spiral screw piece on an outer circumferential surface thereof. A toner opening port  22 , supplying pipe side cams  23 , and a flange  24  are arranged on an outer circumferential side surface of the supplying pipe  20 . The toner opening port  22  is arranged in the vicinity of a leading edge of the supplying pipe  20 . In the present preferred embodiment, the toner opening port  22  preferably opens in a rectangular shape, but is not limited to a specific opening shape. The supplying pipe side cams  23  define a cam mechanism and are arranged on a side of the unused-toner containing unit  11  beyond the toner opening port  22 . The supplying pipe side cams  23  are disposed at positions in a circumferential direction of the supplying pipe  20 , one of the positions being out of phase with the other by about 180 degrees, for example. Each of the supplying pipe side cams  23  has a spiral protruding portion on one side thereof along an outer circumferential surface of the supplying pipe  20 . A portion protruding in a circular ring shape from the supplying pipe  20  defines the flange  24 , which is arranged on the side of the unused-toner containing unit  11  beyond the supplying pipe side cams  23 . 
     The cover  30  preferably is a cylindrical pipe and includes a cover opening port  32  on a side surface thereof, cover side cams  33  on an inner circumferential side thereof, and a flange  34  on an outer circumferential side thereof. In the present preferred embodiment, the cover opening port  32  preferably opens in a rectangular shape, but is not limited to a specific opening shape. An opening shape of the cover opening port  32  is preferably identical or substantially similar to that of the toner opening port  22 . The cover side cams  33  define a cam mechanism and are arranged on the side of the unused-toner containing unit  11  beyond the cover opening port  32 . Each of the cover side cams  33  also has a spiral protruding portion on one side, each of the spiral protruding portions arranged to be engaged with the respective spiral protruding portions of the supplying pipe side cams  23  when attached to the supplying pipe  20 . A portion protruding in a circular ring shape from the cover  30  defines the flange  34 , which is arranged at a trailing edge which is on the side of the unused-toner containing unit  11  beyond the cover side cams  33 . The flange  24  is greater in size than the flange  34 . 
     Retaining portions  23   a  are protrusions arranged at respective leading edge sides of the supplying pipe side cams  23  and  23 . Retaining portions  33   a  are protrusions arranged at respective trailing edge sides of the cover side cams  33 . The cover  30  is biased by the spring  40  in a direction departing from the supplying pipe  20 , however, when the retaining portions  23   a  engage with the retaining portions  33   a , the cover  30  is prevented from being removed from the supplying pipe  20  at a closing position to be described later. 
     The spring  40  has a function of biasing the supplying pipe  20  as a compression spring in an axial direction and a function of biasing the supplying pipe  20  as a torsion spring in the axial direction. The spring  40  is locked by the flange  34  of the cover  30  and the flange  24  of the supplying pipe  20 . In this state, the spring  40  biases in a direction in which the cover  30  departs from the supplying pipe  20  with respect to the axial direction, and the spring  40  also biases in a direction in which the supplying pipe side cams  23  engage with the cover side cams  33  with respect to the circumferential direction. 
     The actions of the supplying pipe side cams  23  and of the cover side cams  33  will now be described in detail. As illustrated in  FIG. 3A , when a pressing force is applied with respect to the cover  30  in a direction of the unused-toner containing unit  11  from the leading edge side of the supplying pipe  20 , the cover  30  moves in response to the pressing force while spirally rotating in the direction of the unused-toner containing unit  11 . Then, with respect to the supplying pipe  20 , the cover  30  comes to an opening position where the toner opening port  22  and the cover opening port  32  match to each other to open the toner opening port  22 . As illustrated in  FIG. 3B , when the pressing force applied in the direction of the unused-toner containing unit  11  from the leading edge side of the supplying pipe  20  is gradually released, the cover  30  moves in a direction of arrow α relatively with respect to the supplying pipe  20  in response to a biasing force of the spring  40  applied in the axial direction. At the same time, in response to a biasing force of the spring  40  applied in the circumferential direction, the cover  30  moves in a direction of arrow β in which the cover side cams  33 ,  33  engage with the respective supplying pipe side cams  23 . As illustrated in  FIG. 3C , the cover  30  moves while spirally rotating, and the retaining portions  23   a  engage with the respective retaining portions  33   a . In this state, with respect to the supplying pipe  20 , the cover  30  comes to a closing position where the toner opening port  22  of the supplying pipe  20  is closed by the cover  30 . With this configuration, the opening position establishes a skewed positional relationship with the closing position. In order to simplify  FIGS. 3A ,  3 B, and  3 C, the cover  30  is illustrated in a perspective view, and illustrations of the spring  40 , the retaining portions  23   a  and  33   a  are omitted. 
     A process of removing the toner cartridge  10  from the image forming device will now be described in detail.  FIG. 4A  illustrates a situation where the toner cartridge  10  is attached to the image forming device. In  FIG. 4A , when the supplying pipe  20  is attached to the toner hopper  5 , an attaching portion  8  makes contact with the cover  30 . As a result, the pressing force is applied to the cover  30  in the direction of the unused-toner containing unit  11 . Thus, the cover  30  comes to the opening position with respect to the supplying pipe  20 . At this time, in the supplying pipe  20 , the flange  24  makes contact with the outside of a toner hopper opening port side surface  5   a , and the toner cartridge  10  and the toner hopper  5  are connected with each other. 
       FIG. 4B  illustrates a situation where the toner cartridge  10  is removed from the image forming device. In  FIG. 4B , the pressing force against the cover  30  is released when the supplying pipe  20  is removed from the toner hopper  5 . At this time, the cover  30  moves in the direction of arrow α relatively with respect to the supplying pipe  20  in response to the biasing force of the spring  40  applied in the axial direction. At the same time, the supplying pipe side cams  23  are engaged with the respective cover side cams  33  by the biasing force of the spring  40  applied in the circumferential direction, and the cover  30  moves in the direction of arrow β in the circumferential direction. In other words, the cover  30  moves from the opening position to the closing position while rotating spirally, and the toner opening port  22  is closed by the cover  30 . In  FIGS. 4A and 4B , for easier understanding of explanation, the illustrations of the supplying pipe side cams  23  and the cover side cams  33  are omitted. An opening port  5   b  of the toner hopper  5  is greater than the flange  34  and smaller than the flange  24  in size. Accordingly, when attaching the toner cartridge  10  to the toner hopper  5 , the flange  34  can be easily inserted into the toner hopper  5  through the opening port  5   b , and the flange  24  is positioned by the opening port  5   b . The flange  24  locks the spring  40  and is positioned with respect to the toner hopper  5 . 
     Some advantages of the present preferred embodiment over the conventional art will now be described. As illustrated in  FIGS. 5A and 5B , the present preferred embodiment of the present invention and the conventional art will be compared with reference to the sectional views of the toner opening ports  22  and  122  in the axial direction and in the circumferential direction. 
     As illustrated in  FIG. 5A , in the conventional art, when closing the toner opening port  122 , a cover  130  and a cover opening port  132  linearly move in a direction of arrow α in the axial direction with respect to a supplying pipe  120 . As a result, when closing the cover  130 , the toner opening port  122  cannot be closed without leaking toner remaining around the toner opening port  122 . In particular, in a second-half operation of closing the cover  130 , the cover  130  pushes out the residual toner remaining around the toner opening port  122 . 
     As illustrated in  FIG. 5B , in the present preferred embodiment of the present invention, when closing the toner supplying port  22 , the cover  30  moves from the opening position to the closing position in the direction of arrow α in the axial direction and in the direction of arrow β in the circumferential direction, as previously described. In other words, the cover  30  moves from the opening position to the closing position while spirally rotating. As a result, the cover  30  can close the toner opening port  22  while scooping up the toner remained around the toner supplying port  22 . Thus, the toner leakage at the time of removing the toner cartridge  10  from the toner hopper  5  can be minimized. 
     Further, the cam mechanism can be configured with a simple cam shape which is defined by the supplying pipe side cams  23  and the cover side cams  33 . Furthermore, by providing two cams on the supplying pipe side and on the cover side, respectively, the cover  30  can be reliably reciprocated between the opening position and the closing position. Moreover, after the toner cartridge  10  is removed from the toner hopper  5 , since the toner opening port  22  is reliably closed by the cover  30  due to the biasing force of the spring, the toner leakage can be reliably prevented even after the toner cartridge  10  is removed from the toner hopper  5 . 
     The present invention is not limited to the toner cartridge  10  arranged to supply toner but can be applied, with similar advantages, to other toner containers that are removably provided to image forming devices, such as a connection portion etc. arranged between a waste toner box and an image forming device. 
     While the present invention has been described with respect to preferred embodiments thereof, it will be apparent to those skilled in the art that the disclosed invention may be modified in numerous ways and may assume many embodiments other than those specifically set out and described above. Accordingly, the appended claims are intended to cover all modifications of the present invention that fall within the true spirit and scope of the present invention.