Rotary developing device for an image forming apparatus

• US 5,565,973 A
• Filed: 04/11/1995
• Issued: 10/15/1996
• Est. Priority Date: 04/11/1994
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Suzuki, Minoru, Kimura, Noriyuki, Ueno, Yuichi, Ishikawa, Tomoji, Fujishiro, Takatsugu, Aoki, Katsuhiro, Matsushiro, Hiroyuki, Kobayashi, Chiyako
• Primary Examiner(s): Smith, Matthew S.
• Application Number:
  US08/420,058
• Time in Patent Office: 553 Days
• Field of Search: 355/326 R, 355/327, 355/260, 355/208, 355/203, 355/210, 355/200, 355/245, 222/DIG. 1, 141/363, 141/365, 353/204
• US Class Current: 399/227
• CPC Class Codes: G03G 15/0126 using a solid developer
• CPC Class Codes: G03G 2215/0177 Rotating set of developing units

Abstract

In an image forming apparatus, a rotary developing device effects development by revolving a plurality of developing sections around a rotary shaft until any one of them reaches a developing position where it faces an image carrier. Cartridges are respectively mounted to hoppers included in the developing sections. Guides are provided on the inner periphery of each cartridge in order to guide toner, moving due to the revolution or the developing device, toward a toner outlet formed in the cartridge. Even when the amount of toner remaining in the cartridge is small, the entire toner is replenished into the associated hopper and fully consumed.

Claims

1. A rotary developing device comprising:

a plurality of developing sections arranged around a rotary shaft;

a plurality of hoppers respectively constructed integrally with and communicated to said plurality of developing sections, and respectively storing powdery developers to be supplied to said plurality of developing sections;

a plurality of developer containers respectively removably mounted to and communicated to said plurality of hoppers, and respectively containing powdery developers to be replenished into said plurality of hoppers; and

a plurality of guide portions respectively provided in said plurality of developer containers and for guiding, when said plurality of developing sections are revolved, said powdery developers to outlets respectively formed in said plurality of toner container;

wherein said plurality of developing sections are revolved around said rotary shaft until any one of said developing sections reaches a developing section where said one developing section faces an image carrier, while said powdery developer is replenished from one of said plurality of developer containers into said respective hopper due to revolution of said developing sections.

2. A device as claimed in claim 1, wherein said powdery developer is replenished from said respective developer container into said respective hopper via a connecting portion connecting said developer container to said hopper during the revolution of said developing sections.

3. A device as claimed in claim 2, wherein an inner surface of said respective developer container located at a downstream side, with respect to a direction in which said powdery developer moves in said developer container toward an opening constituting said connecting portion during the revolution of said developing sections, is protruded into said developer container relative to an inner surface located at an upstream side with respect to said direction.

4. A rotary developing device comprising:

a plurality of developing sections arranged around a rotary shaft;

a plurality of hoppers respectively constructed integrally with said plurality of developing sections, and respectively communicated to said plurality of developing sections in a lengthwise direction of said developing sections, and each storing a powdery developer to be supplied to said respective developing section;

a supply member for supplying a developer carrier with a developer from a first conveying region for supply formed in the lengthwise direction of each of said plurality of developing sections; and

conveying means for conveying said developer from said respective hopper to said respective first conveying region, and for returning to said respective hopper a developer collected in a second conveying region for collection, which is separated from said first conveying region, without being deposited on said developer carrier;

wherein said plurality of developing sections are revolved around said rotary shaft until one of said developing sections reaches a developing position where said one developing section faces an image carrier, and wherein said device is operable in an initial start-up mode for driving said conveying means, while maintaining said supply member inoperative, such that said developer replenished into said respective hopper is conveyed over an entire dimension of said first conveying region.

5. A device as claimed in claim 4, wherein said device is removably mounted to a body of an image forming apparatus.

6. A device as claimed in claim 4, wherein said conveying means comprises:

a first conveying member for conveying said developer from said respective hopper to an end of said respective developing section opposite to said one end in a lengthwise direction of said first conveying region; and

a second conveying member for returning said developer conveyed by said first conveying member to said other end and said developer collected in said second conveyance region to said one end.

7. A device as claimed in claim 6, wherein only said first conveying member is driven when said conveying means is driven in said initial start-up mode.

8. A device as claimed in claim 4, wherein said conveying means comprises:

a first conveying member for conveying said developer from said respective hopper to an end of said respective developing section opposite to said one end in a lengthwise direction of said first conveying region; and

a second conveying member for returning said developer conveyed by said first conveying member to said other end and said developer collected in said second conveying region to said one end.

9. A device as claimed in claim 8, wherein said first conveying member and said second conveying member are driven when said conveying means is driven in said initial start-up mode.

10. An image forming apparatus comprising:

a rotary developing device comprising a plurality of developing sections arranged around a rotary shaft, and for effecting development by revolving said plurality of developing sections until any one of said developing sections reaches a developing position where said one developing section faces an image carrier, said developing device being removably mounted to a body of said image forming apparatus;

distinguishing means for determining whether or not said developing device mounted to said image forming apparatus is new and contains no developers in said plurality of developing sections, wherein said distinguishing means comprises a bar code label adhered to said developing device for identification, and bar code reading means for reading said bar code label; and

means for controlling supplying developer to said developing device based on whether said developing device is distinguished to be new.

11. An image forming apparatus comprising:

a rotary developing device comprising a plurality of developing sections arranged around a rotary shaft, and for effecting development by revolving said plurality of developing sections until any one of said developing sections reaches a developing position where said one developing section faces an image carrier, said developing device being removably mounted to a body of said image forming apparatus;

a mark indicative of a reference position of said developing device including a bar code label representative of information for identification and adhered to said developing device;

sensing means responsive to said reference position including bar code reading means capable of reading said bar code label; and

means for controlling supplying developer to said developing device based on an output of said sensing means.