Patent EP0740223A2 successfully refreshed from Google Patents.
EP0740223A2
Expired / Lapsed
EP
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Heater controlling apparatus and a fixing apparatus of an electrophotographic apparatus in use therewith
Assignee: Konica Minolta Inc
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Filing: 1996-04-23
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Granted: —
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Expires: 2016-04-23
Abstract
Abstract A fixing unit for printers and copiers includes: a heater (4), adapted in the fixing unit, for heating a fixing member to fix a toner image on a sheet; a zero-cross detector (5) for detecting zero-cross timing of voltage of electric power supply (1); a switching circuit (2,3) for turning on and off the electric power to the heater; a controller (9) for controlling the switching operation of the circuit so as to provide a first state that the electric power is continuously supplied to the heater (4) from a zero-cross point to other zero-cross point and a second state that the electric power is not supplied to the heater from a zero-cross point to other zero-cross point. In the fixing unit, the electric power is supplied to the heater with a intermittent pattern, including the second state, for a predetermined period after at least one of a turn-on operation of the heater and a turn-off operation of the heater.
Inventors
- 👤 Tadao Kishimoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 07:25
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
156 words
A fixing apparatus for an image forming apparatus, comprising: a heater, adopted in said fixing apparatus, for heating a fixing member; a zero-cross detecting means for detecting zero-cross timing of electric power that a voltage of said electric power is at zero volt; a switching means for turning on and turning off supply of said electric power to said heater; a control means for controlling said switching means so as to provide a first state that said electric power is continuously supplied to said heater from a zero-cross point to other zero-cross point and a second state that said electric power is prevented to be supplied to said heater from a zero-cross point to other zero-cross point; wherein said electric power is supplied to said heater with a intermittent pattern, including said second state, for a predetermined period after at least one of a turn-on operation of said heater and a turn-off operation of said heater.
Claim 2
Dependent Claim
40 words
The fixing apparatus of claim 1, wherein said control means generates intermittent pulses in said predetermined period and said switching means turns on and turns off supply of said electric power to said heater in response to said intermittent pulses.
Claim 3
Dependent Claim
41 words
The fixing apparatus of claim 1, wherein said control means generates continuous pulses in a period other than said predetermined period and said switching means allows continuous supply of said electric power to said heater in response to said continuous pulses.
Claim 4
Dependent Claim
106 words
The fixing apparatus of claim 1, wherein said intermittent pattern is a pattern of repeating one of the patterns that: (1) a half cycle among alternative current of one cycle is used; (2) one or two half-cycles among alternative current of one and a half cycles are used; (3) one through three half-cycles among alternative current of two cycles are used; (4) one through four half-cycles among alternative current of two and a half cycles are used; (5) one through five half-cycles among alternative current of three cycles are used; and (6) two half-cycles with a same polarity among alternative current of three cycles are used.
Claim 5
Dependent Claim
22 words
The fixing apparatus of claim 1, wherein said heater includes a heat source having a color temperature of not more than 2600°K.
Claim 6
Dependent Claim
175 words
A fixing apparatus for an image forming apparatus, comprising: a heater, adopted in said fixing apparatus, for heating a fixing member; a zero-cross detecting means for detecting zero-cross timing of electric power that a voltage of said electric power is at zero volt; a switching means for turning on and turning off supply of said electric power to said heater; a direct current power supplying means for generating a direct current from an alternative current of said electric power; a control means for controlling said switching means so as to provide a first state that said electric power is continuously supplied to said heater from a zero-cross point to other zero-cross point and a second state that said electric power is prevented to be supplied to said heater from a zero-cross point to other zero-cross point; wherein said electric power is supplied to said heater with a intermittent pattern, including said second state, for a predetermined period after at least one of a turn-on operation of said heater and a turn-off operation of said heater.
Claim 7
Dependent Claim
26 words
The fixing apparatus of claim 6, wherein said alternative current of said electric power, supplied to said direct current power supplying means, is of a non-sine-wave.
Claim 8
Dependent Claim
19 words
The fixing apparatus of claim 7, wherein said alternative current include a pulse current of a peak voltage thereof.
Claim 9
Dependent Claim
19 words
The fixing apparatus of claim 6, wherein said intermittent pattern is a half-wave drive pattern having a fixed polarity.
Claim 10
Dependent Claim
78 words
The fixing apparatus of claim 9, wherein said half-wave drive pattern having a fixed polarity is a pattern of repeating one of the patterns that: (1) a half cycle among alternative current of one cycle is used; (2) a half cycle among alternative current of two cycles is used; (3) a half cycle among alternative current of three cycles is used; and (4) two half cycles having the same polarity among alternative current of three cycles are used.
Claim 11
Dependent Claim
49 words
The fixing apparatus of claim 6, wherein said direct current power supplying means includes a switching regulator; and said fixing apparatus further comprising: a common choke for reducing noise; wherein said common choke is provided on a line through which said alternative current is supplied to said switching regulator.
References Cited (Backward Citations)
No citation records indexed.
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