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US4949124A Expired / Lapsed US ⏱️ 0.0 years remaining

Image forming apparatus having plural developing units and an arrangement for selecting the developing unit having the highest use count

Assignee: Minolta Co Ltd
•
Filing: 1988-06-07
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Granted: 1990-08-14
•
Expires: 2008-06-07
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Abstract

Abstract An image forming apparatus has plural developing units which perform image forming operations with use of either one of the developing units. The image forming apparatus includes a counting arrangement for counting a respective number of times of use of the plural developing units or with respect to each of the colors of developers contained in the plural developing units. A developing unit is selected having the highest frequency in use among the developing units when the image forming apparatus is brought into the initial mode thereof.

Inventors

  • 👤 Keiji Kusumoto
  • 👤 Masazumi Ito
  • 👤 Yoshiaki Takano
  • 👤 Takashi Noda

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 16:21
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/01; G03G15/0105; G03G15/0126; G03G15/06; G03G15/08

Claims Analysis

Total Claims: 30
Claim 1
Independent Claim 69 words
An image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units further including: means for counting respective number of times in use with respect to each of the plural developing units; and means for selecting the developing unit having the largest number of times in use when a power source for the image forming apparatus is turned on.
Claim 2
Dependent Claim 69 words
An image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units further including: means for counting respective number of times in use with respect to each of the plural developing units; and means for selecting the developing unit having the largest number of times in use when a power source for the image forming apparatus is turned on.
Claim 3
Dependent Claim 57 words
An image forming apparatus as claimed in claim 1, wherein the number of times in use is counted with respect to each developing unit by respective counters and, when either one of the counters comes up to a predetermined number first, the developing unit corresponding to the counter having counted said predetermined number at first is selected.
Claim 4
Dependent Claim 29 words
An image forming apparatus as claimed in claim 2, all of the counters are reset when either one of the counters comes up to said predetermined number at first.
Claim 5
Dependent Claim 65 words
An image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units further including: means for counting respective number of times in use with respect to each of the plural developing units, and means for selecting the developing unit having the largest number of times in use after an image forming operation has been completed.
Claim 6
Dependent Claim 65 words
An image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units further including: means for counting respective number of times in use with respect to each of the plural developing units, and means for selecting the developing unit having the largest number of times in use after an image forming operation has been completed.
Claim 7
Dependent Claim 57 words
An image forming apparatus as claimed in claim 4, wherein the number of times in use is counted with respect to each developing unit by respective counters and, when either one of the counters comes up to a predetermined number first, the developing unit corresponding to the counter having counted said predetermined number at first is selected.
Claim 8
Dependent Claim 29 words
An image forming apparatus as claimed in claim 5, all of the counters are reset when either one of the counters comes up to said predetermined number at first.
Claim 9
Dependent Claim 84 words
An image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units further including: means for counting respective number of times in use with respect to each of the plural developing units; means for entering conditions for image forming; and means for selecting the developing unit having the largest number of times in use when no image forming operation is started within a predetermined time period after said conditions for image forming were entered.
Claim 10
Dependent Claim 84 words
An image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units further including: means for counting respective number of times in use with respect to each of the plural developing units; means for entering conditions for image forming; and means for selecting the developing unit having the largest number of times in use when no image forming operation is started within a predetermined time period after said conditions for image forming were entered.
Claim 11
Dependent Claim 57 words
An image forming apparatus as claimed in claim 7, wherein the number of times in use is counted with respect to each developing unit by respective counters and, when either on of the counters comes up to a predetermined number first, the developing unit corresponding to the counter having counted said predetermined number at first is selected.
Claim 12
Dependent Claim 28 words
An image forming apparatus as claimed in claim 8, all of the counters are reset when either one of the counters comes up to said predetermined number first.
Claim 13
Dependent Claim 109 words
An image forming apparatus having plural developing units in which developers of colors different from each other and which performs image forming operations with use of either one of the plural developing units further including: means for detecting a color of the developer contained in the developing unit which is used presently; means for counting respective number of times of image forming operation with respect to each color of the developer; and means for selecting a developing unit containing developer of the color with respect to which the number of times of image forming operation is maximum when a power source for the image forming apparatus is turned on.
Claim 14
Dependent Claim 109 words
An image forming apparatus having plural developing units in which developers of colors different from each other and which performs image forming operations with use of either one of the plural developing units further including: means for detecting a color of the developer contained in the developing unit which is used presently; means for counting respective number of times of image forming operation with respect to each color of the developer; and means for selecting a developing unit containing developer of the color with respect to which the number of times of image forming operation is maximum when a power source for the image forming apparatus is turned on.
Claim 15
Dependent Claim 67 words
An image forming apparatus as claimed in claim 10, wherein the number of times in use is counted with respect to color of developer contained in each developing unit by respective counter and, when either one of the counters comes up to a predetermined number first, the developing unit containing developer of the color corresponding to the counter having counted said predetermined number at first is selected.
Claim 16
Dependent Claim 28 words
An image forming apparatus as claimed, in claim 11, all of the counters are reset when either one of the counters comes up to said predetermined number first.
Claim 17
Dependent Claim 124 words
An image forming apparatus having plural developing units in which developers of colors different from each other and which performs image forming operations with use of either one of the plural developing units further including: means for detecting a color of the developer contained in the developing unit which is used presently; means for counting respective number of times of image forming operation with respect to each color of the developer; means for entering conditions for image forming; and means for selecting a developing unit containing developer of the color with respect to which the number of times of image forming operation is maximum when no image forming operation is started within a predetermined time period after said conditions for image forming were entered.
Claim 18
Dependent Claim 124 words
An image forming apparatus having plural developing units in which developers of colors different from each other and which performs image forming operations with use of either one of the plural developing units further including: means for detecting a color of the developer contained in the developing unit which is used presently; means for counting respective number of times of image forming operation with respect to each color of the developer; means for entering conditions for image forming; and means for selecting a developing unit containing developer of the color with respect to which the number of times of image forming operation is maximum when no image forming operation is started within a predetermined time period after said conditions for image forming were entered.
Claim 19
Dependent Claim 67 words
An image forming apparatus as claimed in claim 13, wherein the number of times in use is counted with respect to color of developer contained in each developing unit by respective counter and, when either one of the counters comes up to a predetermined number first, the developing unit containing developer of the color corresponding to the counter having counted said predetermined number at first is selected.
Claim 20
Dependent Claim 28 words
An image forming apparatus as claimed in claim 14, all of the counters are reset when either one of the counters comes up to said predetermined number first.
Claim 21
Dependent Claim 70 words
In an image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units, a method comprising the steps of: counting respective number of times in use with respect to each of the plural developing units; and selecting the developing unit having the largest number of times in use when a power source for the image forming apparatus is turned on.
Claim 22
Dependent Claim 70 words
In an image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units, a method comprising the steps of: counting respective number of times in use with respect to each of the plural developing units; and selecting the developing unit having the largest number of times in use when a power source for the image forming apparatus is turned on.
Claim 23
Dependent Claim 65 words
In an image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing, a method comprising the steps of: counting respective number of times in use with respect to each of the plural developing units, and selecting the developing unit having the largest number of times in use after an image forming operation has been completed.
Claim 24
Dependent Claim 65 words
In an image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing, a method comprising the steps of: counting respective number of times in use with respect to each of the plural developing units, and selecting the developing unit having the largest number of times in use after an image forming operation has been completed.
Claim 25
Dependent Claim 83 words
In an image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units, a method comprising the steps of: counting respective number of times in use with respect to each of the plural developing units; entering conditions for image forming; and selecting the developing units having the largest number of times in use when no image forming operation is started within a predetermined time period after said conditions for image forming were entered.
Claim 26
Dependent Claim 83 words
In an image forming apparatus having plural developing units which performs image forming operation with use of either one of the developing units, a method comprising the steps of: counting respective number of times in use with respect to each of the plural developing units; entering conditions for image forming; and selecting the developing units having the largest number of times in use when no image forming operation is started within a predetermined time period after said conditions for image forming were entered.
Claim 27
Dependent Claim 106 words
In an image forming apparatus having plural developing units in which developers of colors different from each other perform image forming operations with use of either one of the plural developing units, a method comprising the steps of: detecting a color of the developer contained in the developing unit which is used presently; counting respective number of times of image forming operation with respect to each color of the developer; and selecting a developing unit containing developer of the color with respect to which the number of times of image forming operation is maximum when a power source for the image forming apparatus is turned on.
Claim 28
Dependent Claim 106 words
In an image forming apparatus having plural developing units in which developers of colors different from each other perform image forming operations with use of either one of the plural developing units, a method comprising the steps of: detecting a color of the developer contained in the developing unit which is used presently; counting respective number of times of image forming operation with respect to each color of the developer; and selecting a developing unit containing developer of the color with respect to which the number of times of image forming operation is maximum when a power source for the image forming apparatus is turned on.
Claim 29
Dependent Claim 118 words
An image forming apparatus having plural developing units in which developers of colors different from each other perform image forming operations with use of either one of the plural developing units, a method comprising the steps of: detecting a color of the developer contained in the developing unit which is used presently; counting respective number of times of image forming operation with respect to each color of the developer; entering conditions for image forming; and selecting a developing unit containing developer of the color with respect to which the number of times of image forming operation is maximum when no image forming operation is started within a predetermined time period after said conditions for image forming were entered.
Claim 30
Dependent Claim 118 words
An image forming apparatus having plural developing units in which developers of colors different from each other perform image forming operations with use of either one of the plural developing units, a method comprising the steps of: detecting a color of the developer contained in the developing unit which is used presently; counting respective number of times of image forming operation with respect to each color of the developer; entering conditions for image forming; and selecting a developing unit containing developer of the color with respect to which the number of times of image forming operation is maximum when no image forming operation is started within a predetermined time period after said conditions for image forming were entered.

References Cited (Backward Citations)

US3886329A Cited
US3960445A Cited
US4222660A Cited
US4416533A Cited
US4453821A Cited
US4496237A Cited
US4634258A Cited
JPS60230168A Cited
JPS6173974A Cited
JPS61117576A Cited
US4720730A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-08-13 1994-02-12 1994-08-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-08-13 1998-02-12 1998-08-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-08-13 2002-02-12 2002-08-14 $7700.00 Window Closed / Lapsed

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