Image forming devices such as copiers, printers, facsimile machines, and the like, produce residual toner that is not used during the printing process. This residual toner should be removed from the image transfer area and stored in storage location. The storage location should be sized to hold an adequate amount of the waste toner prior to removal from the image forming device. One solution is to provide a large capacity waste toner reservoir that can hold a large amount of waste toner. However, it is desirable for the overall size of the image forming device to be as small as possible. Therefore, a mechanism is needed to maximize the amount of waste toner that can be stored within a waste toner reservoir.
The waste toner mechanism should utilize a majority of the storage space within the waste toner reservoir. Previous designs often need to be replaced prior to the majority of the storage capacity being filled by waste toner. This was often caused because there was no mechanism for directing the waste toner throughout the reservoir. Further, the waste toner mechanism should be constructed to prevent waste toner from leaking from the waste toner reservoir.
Many previous waste toner reservoirs were positioned with the reservoir inlet being positioned at the upper reaches of the waste toner reservoir. These designs could utilize gravity to cause the waste toner to fall into the reservoir without the need for any additional waste toner mechanism to move and direct the toner. However, with the demand for smaller overall sizes for the image forming devices, space constraints may not allow for the waste toner to be introduced into an upper section of the waste toner reservoir. Therefore, some mechanism is needed to move the toner from a toner inlet at a lower section of the waste toner reservoir into other, vertically higher areas.
The present invention is directed to embodiments to move toner within an image forming device. One embodiment of the present invention is directed to a conveyor device to move waste toner within an interior of a waste toner reservoir. The conveyor device has a first end positioned in proximity to an inlet into the waste toner reservoir, and a second end positioned vertically above the first end. The conveyor device operates to move the toner from a lower position within the waste toner reservoir to the vertically elevated position.
The present invention is directed to embodiments of a device for moving toner within a waste toner reservoir 10 of an image forming device.
The supply mechanism 30 has an elongated shape that extends the length of the cartridge 40. In this embodiment, the supply mechanism is a screw auger having a central shaft and helical fins that extend around the shaft. A first end of the supply mechanism 30 extends towards the waste toner reservoir 10, with a second end 33 at the opposite side of the cartridge 40. A rotation device 50 is operatively connected to the second end 33 to rotate the supply mechanism. In one embodiment, the cartridge 40 includes a gear 49 that operatively connects with a gear train (not illustrated) in a main printer body. The gear train in the main printer body is driven by a main printer body power supply. When the cartridge 40 is mounted in the main body, cartridge gear 49 mates with the main body gear train and the rotation device 50 causes rotation of the supply mechanism 30 to move the waste toner from the cartridge 40 towards the waste toner reservoir 10.
The wire auger 25 has a helical configuration that extends around the guide 22. A first end of the wire auger 26 is connected to the supply mechanism 32, and a second end 27 is positioned in proximity to the second end 24 of the guide 20. The wire auger 25 is loosely positioned around the guide 22 to rotate and direct the waste toner at the inlet 12 towards the vertically elevated section 16 of the waste toner reservoir 10. The wire auger 25 may be more flexible than the guide 22 to conform to the curved shape of the guide 22. The helical shape prevents the wire auger 22 from detaching from the supply mechanism 30, even during rotation. The second end 24 of the guide 20 is loose (i.e., not connected with the inner wall of the waste toner reservoir 10) allowing it to rotate about the guide 20. In one embodiment, the wire auger 25 is constructed of a metal strip about 0.5 mm thick by about 3 mm wide.
The guide 22 and the wire auger 25 may be positioned within an interior of the waste toner reservoir 10. This positioning prevents the auger 25 from contacting the inner edges of the waste toner reservoir 10 which could create noise which is audible to a user, or cause wear which could result in waste toner leakage.
In this embodiment, the first end of the wire auger 25 is attached to the end 32 of the supply mechanism 30 and the wire auger 25 is wrapped around the end of the supply mechanism 30. In one embodiment, an end of the wire auger 25 is positioned within a hole on the periphery of the supply mechanism. The connection causes rotation of the wire auger 25 through the rotation of the supply mechanism 30. Therefore, the rotation device 50 that drives the supply mechanism 30 also rotates the wire auger 25. The direct connection between the wire auger 25 and supply mechanism 30 also facilitates movement of the waste toner as there is no void or gap in the mechanisms that move the waste toner. Instead, the waste toner is directly transferred from the supply mechanism 30 to the wire auger 25.
The first end 23 of the guide 22 may also be attached to the end of the supply mechanism 30. In one embodiment, the guide end 23 is mounted within an opening centered within the end 32 supply mechanism 30 as illustrated in
The orientation of the conveyor mechanism 20 moves the waste toner from the inlet 12 to an elevated positioned within the waste toner reservoir 10.
As the toner level rises within the reservoir 10, the conveyor mechanism 20 aids the supply mechanism 30 in pulling toner into the reservoir 10, and provides a channel to pull the toner to the top of the reservoir 10. Since the toner is being actively pulled instead of being pushed from below by the conveyor mechanism 20, the toner remains more fluid which reduces the overall torque on the system and the demands on the rotation device 50.
In one embodiment, the conveyor mechanism 20 is positioned away from the inlet 12. The first end of the conveyor mechanism is positioned at a first vertical position that is distanced from the inlet 12 with the second end positioned at an elevated second position. In one embodiment, the first end of the conveyor mechanism 20 is positioned in proximity to a bottom wall 19. Further, the conveyor mechanism 20 is powered by a separate device than the supply mechanism 30.
The lower end of the belt 51 may extend around the supply mechanism 30. The contact between the belt 51 and supply mechanism 30 is sufficient to cause the belt to move. In one embodiment, the supply mechanism second end 32 has a channel to receive and maintain the position of the belt 51. In another embodiment, belt 51 is driven by a separate mechanism positioned at a vertically lower position within the reservoir 10.
The support member 52 is positioned at a vertically elevated position above the inlet 12. The support member 52 may include a circular member about which the belt 51 moves. In one embodiment, support member 52 comprises a rotating member.
The embodiment of
The image forming device may produce color or single color images. For multi-color images, a plurality of different cartridges 40 each containing a different color of toner produce a composite toner image in an overlapping fashion. For single-color devices, a single cartridge, usually black, produces the toner image. The image forming device may include an intermediate transfer mechanism that receives the toner image from each cartridge and then transfers the toner images to the media sheet. Alternatively, the image forming device may be a direct transfer with the media sheet being moved past each cartridge and the toner image being transferred directly to the sheet. Examples of image forming devices include Model Numbers C750, C752, C760, and C762, each available from Lexmark International, Inc., of Lexington, Ky., which is the assignee of the present invention.
The waste toner reservoir 10 illustrated in
The present invention may be carried out in other specific ways than those herein set forth without departing from the scope and essential characteristics of the invention. In one embodiment, the supply mechanism 30 is a wire auger. In one embodiment as illustrated in