US3409901A - Automatic toner concentration control for use with crt input - Google Patents

Automatic toner concentration control for use with crt input Download PDF

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Publication number
US3409901A
US3409901A US653140A US65314067A US3409901A US 3409901 A US3409901 A US 3409901A US 653140 A US653140 A US 653140A US 65314067 A US65314067 A US 65314067A US 3409901 A US3409901 A US 3409901A
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United States
Prior art keywords
toner
transistor
crt
signal
level
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US653140A
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English (en)
Inventor
Martin H Dost
Gerald L Wiederhold
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International Business Machines Corp
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International Business Machines Corp
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Publication date
Application filed by International Business Machines Corp filed Critical International Business Machines Corp
Priority to US653140A priority Critical patent/US3409901A/en
Priority to FR9209A priority patent/FR95209E/fr
Priority to GB30072/68A priority patent/GB1211588A/en
Priority to DE1772826A priority patent/DE1772826B2/de
Application granted granted Critical
Publication of US3409901A publication Critical patent/US3409901A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • G—PHYSICS
    • G06—COMPUTING OR CALCULATING; COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K15/00—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers
    • G06K15/02—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers
    • G06K15/14—Arrangements for producing a permanent visual presentation of the output data, e.g. computer output printers using printers by electrographic printing, e.g. xerography; by magnetographic printing
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G03G15/0848—Arrangements for testing or measuring developer properties or quality, e.g. charge, size, flowability
    • G03G15/0849—Detection or control means for the developer concentration
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/55—Self-diagnostics; Malfunction or lifetime display
    • G03G15/553—Monitoring or warning means for exhaustion or lifetime end of consumables, e.g. indication of insufficient copy sheet quantity for a job
    • G03G15/556—Monitoring or warning means for exhaustion or lifetime end of consumables, e.g. indication of insufficient copy sheet quantity for a job for toner consumption, e.g. pixel counting, toner coverage detection or toner density measurement
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S222/00—Dispensing
    • Y10S222/01—Xerography

Definitions

  • This invention pertains to xerographic systems in general and more particularly to a system for automatically controlling the replenishment of toner to a development. mechanism. i v i w Description the prior art.-
  • toner densitymakeup has been found to be a major source of output variations in electrophotographic systems, both of the electrofax and xero. graphic types.
  • several different methods of replenishing a toner supply have been employed.
  • The-most, widely used method is a manual onein which the oper-. ator of the system views the output of the system and manually replenishes the toner when the legibility of the output falls below a subjective level.
  • one such system which may be referred to as a feedback type systern utilizes a photocell scanner'to scan the, output and makesadjustments to the toner. supply whenever the image density falls below a-predetermined level.
  • a feed forward toner control system as distinguished from a feedback toner control 3,409,901 Patented Nov. 5, 1968 See? system.
  • a feedback toner control system is one in which the output print density is monitored and adjustments to the toner in the developing mechanism are made in accordance with the output print variations, whereas a feed forward toner supply or control is one in which corrections to the toner supply are made based onactual calculated toner usage.
  • the instantaneous beam intensity of a cathode .ray tube used for exposing the photoconductor is integrated, and when this integrated signal exceeds a threshold level a supply of toner is released to the associated developing mechanism.
  • the threshold level is varied in accordance with the amount of toner contained in the toner supply bin such that with a large head of toner the threshold level is raised while conversely wit a small head of toner, threshold level is lowered.
  • FIGURE 1 is a block-schematic drawing illustrative of the subject toner control system utilized in a xerographic mode
  • FIGURE 2 is shown a schematic of an integrator and threshold detect means which may be utilized as the toner feed signal means of FIGURE 1;
  • FIGURE 3 is a schematic of a second embodiment of i the novel system wherein the threshold is made variabl in accordance with the toner head.
  • FIGURE 1 a schematic of a commercially available CRT output printer.
  • a conventional xerographic drum 1 including a photoconductor on a conductive backing is shown mounted for rotation about axis 2.
  • thesupports, bearings, drive mechanisms, etc. are not shown for purposes of simplicity.
  • a cathode ray tube 3 of conventional design has its light output beam 4imaged on the surface of the photoconductive drum 1. The photoconductive surface which was previously charged by means of a corona unit 5 is therefore selectively discharged by the light beam 4 to form a latent electrostatic image.
  • the drum then is rotated past a developing station generally indicated at 6 at which toner 7 is cascaded merit.
  • the developing mechanism 6 includes belts 8 with fingers 9 which pick up the toner 7 and carry it to the top of the belt and then dump it over the surface of the 'photoconductive drum 1 holding the latent electrostatic image.
  • the toner supply 7, ask well known in the art, not only contains toner but additionally contains carrier beads to which the toner particles are triboelectrically attracted. As is well known, when the toner supply falls below a certain amount, the carrier beads which are cascaded over the surface of the photconductive drum 1 cease to deposit toner and instead often scrub toner which was previously deposited from the surface. This obviously results in poor image quality.
  • the developed image is rotated into alignment with a transfer station generally designated 10 which includes a corona unit 11.
  • the corona unit 11 deposits a charge on the rear surface of the paper web 12 to thereby pull toner from the photoconductive drum 1 onto the web.
  • the web 12 then is moved through a fusing unit 13 wherein the toner is fused to the paper and the output web is taken as indicated by arrow 14.
  • the drum 1 is then rotated past a cleaning station generally designated as 15 which includes a brush 16 which scrubs the drum clean of any residual toner.
  • the CRT 3 is driven by means of a CRT signal source which is connected along lines 21 and 22 to the grid of the CRT 3.
  • the CRT signal source 20 may constitute any number of sources.
  • the signal source may be taken directly from a computer or may be the output of a flying spot scanner or any other type of document scanner.
  • the intensity signal 'from the CRT signal source which appears on lines 21 and 22 to the CRT 3 is also fed along line 24 to a toner feed signal means 25.
  • the toner feed signal means 25 also receives an on/off signal along line 26 from theCRT signal sourceflhe output of the toner feed signal means 25 is applied along line 27 to the toner feed actuator 28 which is mechanically connected as illustrated by the dotted line 29 to the toner hopper generally designated at 30.
  • the toner feed actuator 28 which is mechanically connected as illustrated by the dotted line 29 to the toner hopper generally designated at 30.
  • One such way is the widely used grate mechanism which will be described in more detail in conjunction with FIGURE 3.
  • the intensity signal from the CRT signal source 20 is fed along lines 21 and 22 and used to modulate the CRT beam intensity as the raster is swept over the face of the tube.
  • the intensity signal 1 is also applied along line 24 to the toner feed signal means 25.
  • the toner feed signal means 25 will have been actuated at the start of the print operation signal along line 26.
  • the intensity signal appearing on line 24 from the CRT signal source is summed in the toner feed signal means 25 and when the summation exceeds a predetermined level, the toner feed signal means provides an output signal level on line 27 to the toner feed actuator 28 which causes the hopper 30 to release a predetermined amount of toner 31 into the developer mechanism 6.
  • the toner feed signal means is reset such that another summation process can take place. In this manner toner is released to the developing mechanism 6 in an amount proportional to the total area printed.
  • FIGURE 2 an integrator for summing the instantaneous beam intensity applied to the cathode ray tube and a threshold detector which detects the level of the integral (integral amount) and generates the toner feed actuator pulse and a reset pulse.
  • the on/off signal from the CRT signal source is applied along line 26 to a relay driver 35 which provides a drive pulse along line 36 to the relay coil 37 which causes the normally open relay arm 38 to come into contact with the fixed contact 39.
  • the beam intensity signal from the CRT signal source which, as previously described in conjunction with FIGURE 1, is applied to the grid of the CRT 3 is also applied along line 24 through resistor 40 and stored in capacitor 41. Resistor 40 and capacitor 41 determine the time constant of the integrator. The charge on capacitor 41 builds up as the pulses from the CRT signal source are applied to line 24. Junction 42, which is connected to one side of capacitor 41 is also connected along line 43 to fixed contact 44.
  • Relay 45 of which fixed contact 44 is a part, is normally open, as will later be described.
  • Capacitor 41 will hold its charge for a long period of time due to the use of the insulated gate field efiect transistor 50.
  • the output from the field effect transistor is applied along line 51 to the base of transistor 52.
  • the combined operation of capacitor 41 and field effect transistor 50 to elfect efficient storage of the charge on capacitor 41 is described in more detail in the IBM Technical Disclosure Bulletin, volume 8, No. 6, 1965 at page 912.
  • Transistor 52 When the charge on capacitor 41 exceeds arcertain level as reflected by a level rise on line 51,. transistor 52 will turn on. Transistor 52 is one transistor ofa conventional flip-flop pair, the other of which is transistor 53. Transistor 52 will be otf until the level appearing on line 51 applied through resistor 70 exceeds a pre-selected level. During the time that transistor 52 is oif, transistor 53 is on since a positive level is applied'to it through resistors 71 and 72. When transistor 53 is on, its collector and line 57 will be at near ground potential. When transistor 52 comes on, transistor 53 will go offsince the potential applied through resistor 72 to its base from the collector of transistor 52 is near ground.
  • the potential appearing at the collector of transistor 53 willswitch from ground to a positive potential. That is, when transistor 52 is 011, the collector of transistor 53 will be at ground potential since it is conducting; whereas, when transistor 52 is on, the collector of transistor 53 will be at the positive collector voltage since it is turned off.
  • the pulses appearing in the collector circuit of transistor 53 are fed along line 55 to lines 56 and 57.
  • Line 56 is connected to a single shot 58 which tires on the leading edge of positive going pulses on line 57 and applies a pulse along line 59 to the relay driver 60 which causes the relay arm 61 to close thereby grounding capacitor 41 and resetting the integrator.
  • This same positive going pulse from the collector of transistor 53 is applied along line 57 to a second single shot 62 which generates a pulse which is applied along line 27 to the toner feed actuator.
  • FIGURE -3 wherein is shown a system highly similar to that shown in FIGURES l and 2 with the added feature that-means are provided for varying the level at-which the flip-flop triggers in accordance with the amount of toner contained in the toner supply box which supplies toner to the developing mechanism.
  • the system of FIGURE 3 is similar in all respects to the systems of FIGURES 1 and 2 with the exception that the aforementioned means for providing a variable threshold to the flip-flop in accordance with toner head is provided.
  • the signal from the CRT signal source is applied to the cathode ray tube 103 and utilized to write on the xerogra'phic drum 101 which, as previously described, forms a latent electrostatic image.
  • the latent electrostatic image is rotated past development mechanism 106, transfer corona unit 111 and the fusing unit 113.
  • the drum is then rotated past the cleaning station 115 and past the corona chargin-g unit 105.
  • the signal applied to the cathode ray tube 103 is as described in FIGURES 1 and 2 integrated through resistor and capacitor 141 and held by capacitor 141.
  • the charge appearing on capacitor 141 appears at the output of insulated gate field efiecttransistor and thus appears at junction 199.
  • Junction 199 is connected through resistor 196 to the negative bias potential as in the case of FIGURE 2 which biases transistor 152 off.
  • resistor 196 In parallel with resistor 196 is a potentiometer resistance which is connected through junction 200 to the negative bias potential.
  • a sliding arm 194 is adapted to move along potentiometer resistance 195.
  • FIGURE 3 Shown in FIGURE 3 is a toner supply box 1 30 which holds a head of toner H which may be fed to the developing mechanism 106.
  • a sensing mechanism composed of a float 190, a rod 191 and a. pivot 192 is utilized to move link 193 which moves arm 194 up and down.
  • arm 194 will be moved upward which will cause less of the negative bias potential to be applied to arm 194.
  • a smaller positive charge on capacitor 141 will be required to provide a net switching voltage through resistor 170 to the base of transistor 152.
  • the output of the transistor pair 152 and 153 is taken from the collector circuit of traansistor 153 along lines 155 and 157 and a pulse is generated in single shot 162 and applied along line 127 to the grate actuator 201.
  • Grate actuator 201 may be a solenoid which drives the grate 202 associated with the toner feed box to accomplish feeding.
  • a toner control system for regulating the amount of toner supplied to the developing mechanism comprising:
  • a toner supply means operative to supply toner to said developing mechanism
  • a toner supply actuator means operative to cause toner to be released from said toner supply means to said developing mechanism
  • a toner feed signal means operative to supply an actuation signal to said toner supply actuator after a predetermined amount of energy from said cathode ray tube has impinged on said photoconductor.
  • the toner control system of claim 4 wherein the threshold of said threshold detector is variable in accordance with the amount of toner held by said toner supply means such that as the amount of toner in said toner supply means decreases the threshold level is lowered.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Dry Development In Electrophotography (AREA)
  • Wet Developing In Electrophotography (AREA)
US653140A 1967-07-12 1967-07-13 Automatic toner concentration control for use with crt input Expired - Lifetime US3409901A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US653140A US3409901A (en) 1967-07-12 1967-07-13 Automatic toner concentration control for use with crt input
FR9209A FR95209E (fr) 1967-07-12 1968-06-11 Systeme de commande d'approvisionnement en substance d'impression.
GB30072/68A GB1211588A (en) 1967-07-12 1968-06-24 Electrostatic printer
DE1772826A DE1772826B2 (de) 1967-07-12 1968-07-09 Vorrichtung zur Regelung der Tonerzufuhr in elektrophotographischen Druckgeraten

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US65284667A 1967-07-12 1967-07-12
US653140A US3409901A (en) 1967-07-12 1967-07-13 Automatic toner concentration control for use with crt input

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US3409901A true US3409901A (en) 1968-11-05

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US (1) US3409901A (fr)
DE (1) DE1772826B2 (fr)
FR (1) FR95209E (fr)
GB (1) GB1211588A (fr)

Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3526338A (en) * 1968-01-02 1970-09-01 Xerox Corp Method and controller for dispensing electroscopic material
US3527387A (en) * 1968-05-24 1970-09-08 Xerox Corp Developer replenishing programming system
US3659556A (en) * 1970-08-19 1972-05-02 Xerox Corp Programmable toner dispenser
US3704468A (en) * 1969-04-25 1972-11-28 Ricoh Kk Electronic graphic recording system
US3739800A (en) * 1971-05-04 1973-06-19 Copystatics Mfg Corp Toner supply system for copying machine
JPS4842739A (fr) * 1971-09-25 1973-06-21
US3757351A (en) * 1971-01-04 1973-09-04 Corning Glass Works High speed electostatic printing tube using a microchannel plate
US3873002A (en) * 1973-04-16 1975-03-25 Xerox Corp Toner dispenser logic control
US3892672A (en) * 1970-08-21 1975-07-01 Addressograph Multigraph Automatic toner concentrate detector and control device
US3924462A (en) * 1971-08-06 1975-12-09 Hoechst Ag Method of measuring the toner concentration of a developer circulating in an electrophotographic reproduction machine
US4035668A (en) * 1975-03-20 1977-07-12 Matsushita Electric Industrial Co., Ltd. Input-interruption type delayed turn-off control timer
US4064834A (en) * 1976-11-19 1977-12-27 A. B. Dick Company Apparatus for sensing the concentration of toner in a developer mix
US4101214A (en) * 1975-01-13 1978-07-18 Minolta Camera Kabushiki Kaisha Toner dispensing device with electrical integrating circuit
US4128329A (en) * 1975-10-03 1978-12-05 Ricoh Company, Ltd. Apparatus for producing bias voltage for use in electrophotographic copying machines
US4135642A (en) * 1977-06-02 1979-01-23 Xerox Corporation Wiper arrangement for toner level sensor
US4296423A (en) * 1978-08-18 1981-10-20 Konishiroku Photo Industry Co., Ltd. Device for adjusting image density in composite information recording apparatus
US4589762A (en) * 1983-06-03 1986-05-20 Agfa-Gevaert N.V. Toner dispensing control
US4610532A (en) * 1983-06-03 1986-09-09 Agfa-Gevaert N.V. Toner dispensing control
US4611905A (en) * 1983-11-01 1986-09-16 Agfa-Gevaert N.V. Toner dispensing control
US4695762A (en) * 1985-06-28 1987-09-22 American Telephone And Telegraph Company, At&T Bell Laboratories Electron beam pumped rod-like light emitters
US4721978A (en) * 1986-10-31 1988-01-26 Xerox Corporation Color toner concentration control system
WO1988009529A1 (fr) * 1987-05-21 1988-12-01 Eastman Kodak Company Appareil permettant de commander le remplacement du colorant organique dans une imprimante electrostatographique
US4807241A (en) * 1985-06-28 1989-02-21 American Telephone And Telegraph Company At&T Bell Laboratories Electron beam pumped laser
US5204698A (en) * 1991-09-11 1993-04-20 Xerox Corporation Toner monitoring in an electrostatographic digital printing machine
US5204699A (en) * 1992-09-14 1993-04-20 Xerox Corporation Apparatus for estimating toner usage
US5279224A (en) * 1992-04-17 1994-01-18 Rockwell International Corporation Charge imaging system for a printing press
US5349377A (en) * 1993-05-17 1994-09-20 Xerox Corporation Printer toner usage indicator with image weighted calculation
US5592298A (en) * 1994-06-03 1997-01-07 Xerox Corporation Apparatus and method for detecting digitized image area coverage by counting pixels
US5636032A (en) * 1995-10-11 1997-06-03 Xerox Corporation System and method for informing a user of a marking material status in a printing environment
US5706037A (en) * 1995-09-28 1998-01-06 Xerox Corporation System and method for overriding a low marking material status in a facsimile environment
US5760795A (en) * 1995-09-27 1998-06-02 Xerox Corporation System and method for overriding a low marking material status in a facsimile environment
US5887221A (en) * 1997-10-20 1999-03-23 Xerox Corporation Signature sensing for optimum toner control with donor roll
US5937225A (en) * 1997-07-21 1999-08-10 International Business Machines Corporation Pixel counting toner or ink use monitor and pixel counting method for monitoring the toner or ink use
US6173134B1 (en) * 1996-12-20 2001-01-09 Fuji Xerox Co., Ltd. Image forming system having toner consumption predicting device
US20020075500A1 (en) * 2000-12-19 2002-06-20 Xerox Corporation Method for providing information for a customer replaceable unit
US6584290B2 (en) 2000-12-19 2003-06-24 Xerox Corporation System for providing information for a customer replaceable unit
US20030139973A1 (en) * 2002-01-23 2003-07-24 Xerox Corporation Method and system for ordering a consumable for a device
US20030142338A1 (en) * 2002-01-25 2003-07-31 Xerox Corporation Method and system for shopping for a consumable for a device
WO2009014520A1 (fr) * 2007-07-25 2009-01-29 Hewlett-Packard Development Company, L.P. Stabilisation de la concentration d' encre dans un système d'addition d'encre solide

Families Citing this family (3)

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Publication number Priority date Publication date Assignee Title
JPS60178472A (ja) * 1984-02-27 1985-09-12 Oki Electric Ind Co Ltd 乾式現像装置
US4669856A (en) * 1984-09-10 1987-06-02 Sharp Kabushiki Kaisha Warning device for developer control
FR2639726B1 (fr) * 1988-11-29 1991-01-11 Bull Sa Dispositif pour la reintroduction, dans un reservoir ouvert a l'air libre, de particules solides de revelateur qui ont ete separees d'un flux gazeux transporteur

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US2777745A (en) * 1952-10-04 1957-01-15 Gen Dynamics Corp Electrostatic recording apparatus
US2890968A (en) * 1955-06-02 1959-06-16 Rca Corp Electrostatic printing process and developer composition therefor
US2956487A (en) * 1955-03-23 1960-10-18 Rca Corp Electrostatic printing
US3348522A (en) * 1962-08-28 1967-10-24 Xerox Corp Automatic toner control system

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Publication number Priority date Publication date Assignee Title
US2777745A (en) * 1952-10-04 1957-01-15 Gen Dynamics Corp Electrostatic recording apparatus
US2956487A (en) * 1955-03-23 1960-10-18 Rca Corp Electrostatic printing
US2890968A (en) * 1955-06-02 1959-06-16 Rca Corp Electrostatic printing process and developer composition therefor
US3348522A (en) * 1962-08-28 1967-10-24 Xerox Corp Automatic toner control system

Cited By (46)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3526338A (en) * 1968-01-02 1970-09-01 Xerox Corp Method and controller for dispensing electroscopic material
US3527387A (en) * 1968-05-24 1970-09-08 Xerox Corp Developer replenishing programming system
US3704468A (en) * 1969-04-25 1972-11-28 Ricoh Kk Electronic graphic recording system
US3659556A (en) * 1970-08-19 1972-05-02 Xerox Corp Programmable toner dispenser
US3892672A (en) * 1970-08-21 1975-07-01 Addressograph Multigraph Automatic toner concentrate detector and control device
US3757351A (en) * 1971-01-04 1973-09-04 Corning Glass Works High speed electostatic printing tube using a microchannel plate
US3739800A (en) * 1971-05-04 1973-06-19 Copystatics Mfg Corp Toner supply system for copying machine
US3924462A (en) * 1971-08-06 1975-12-09 Hoechst Ag Method of measuring the toner concentration of a developer circulating in an electrophotographic reproduction machine
JPS4842739A (fr) * 1971-09-25 1973-06-21
US3873002A (en) * 1973-04-16 1975-03-25 Xerox Corp Toner dispenser logic control
US4101214A (en) * 1975-01-13 1978-07-18 Minolta Camera Kabushiki Kaisha Toner dispensing device with electrical integrating circuit
US4035668A (en) * 1975-03-20 1977-07-12 Matsushita Electric Industrial Co., Ltd. Input-interruption type delayed turn-off control timer
US4128329A (en) * 1975-10-03 1978-12-05 Ricoh Company, Ltd. Apparatus for producing bias voltage for use in electrophotographic copying machines
US4064834A (en) * 1976-11-19 1977-12-27 A. B. Dick Company Apparatus for sensing the concentration of toner in a developer mix
US4135642A (en) * 1977-06-02 1979-01-23 Xerox Corporation Wiper arrangement for toner level sensor
US4296423A (en) * 1978-08-18 1981-10-20 Konishiroku Photo Industry Co., Ltd. Device for adjusting image density in composite information recording apparatus
US4589762A (en) * 1983-06-03 1986-05-20 Agfa-Gevaert N.V. Toner dispensing control
US4610532A (en) * 1983-06-03 1986-09-09 Agfa-Gevaert N.V. Toner dispensing control
US4611905A (en) * 1983-11-01 1986-09-16 Agfa-Gevaert N.V. Toner dispensing control
US4807241A (en) * 1985-06-28 1989-02-21 American Telephone And Telegraph Company At&T Bell Laboratories Electron beam pumped laser
US4695762A (en) * 1985-06-28 1987-09-22 American Telephone And Telegraph Company, At&T Bell Laboratories Electron beam pumped rod-like light emitters
US4721978A (en) * 1986-10-31 1988-01-26 Xerox Corporation Color toner concentration control system
WO1988009529A1 (fr) * 1987-05-21 1988-12-01 Eastman Kodak Company Appareil permettant de commander le remplacement du colorant organique dans une imprimante electrostatographique
US5204698A (en) * 1991-09-11 1993-04-20 Xerox Corporation Toner monitoring in an electrostatographic digital printing machine
US5279224A (en) * 1992-04-17 1994-01-18 Rockwell International Corporation Charge imaging system for a printing press
US5204699A (en) * 1992-09-14 1993-04-20 Xerox Corporation Apparatus for estimating toner usage
US5349377A (en) * 1993-05-17 1994-09-20 Xerox Corporation Printer toner usage indicator with image weighted calculation
US5592298A (en) * 1994-06-03 1997-01-07 Xerox Corporation Apparatus and method for detecting digitized image area coverage by counting pixels
US5760795A (en) * 1995-09-27 1998-06-02 Xerox Corporation System and method for overriding a low marking material status in a facsimile environment
US5706037A (en) * 1995-09-28 1998-01-06 Xerox Corporation System and method for overriding a low marking material status in a facsimile environment
US5636032A (en) * 1995-10-11 1997-06-03 Xerox Corporation System and method for informing a user of a marking material status in a printing environment
US6173134B1 (en) * 1996-12-20 2001-01-09 Fuji Xerox Co., Ltd. Image forming system having toner consumption predicting device
US5937225A (en) * 1997-07-21 1999-08-10 International Business Machines Corporation Pixel counting toner or ink use monitor and pixel counting method for monitoring the toner or ink use
US5887221A (en) * 1997-10-20 1999-03-23 Xerox Corporation Signature sensing for optimum toner control with donor roll
US6975422B2 (en) 2000-12-19 2005-12-13 Xerox Corporation Method for providing information for a customer replaceable unit
US20020075500A1 (en) * 2000-12-19 2002-06-20 Xerox Corporation Method for providing information for a customer replaceable unit
US6584290B2 (en) 2000-12-19 2003-06-24 Xerox Corporation System for providing information for a customer replaceable unit
US20050286070A1 (en) * 2000-12-19 2005-12-29 Xerox Corporation Method for providing information for a customer replaceable unit
US20030139973A1 (en) * 2002-01-23 2003-07-24 Xerox Corporation Method and system for ordering a consumable for a device
US7124097B2 (en) 2002-01-23 2006-10-17 Xerox Corporation Method and system for ordering a consumable for a device
US20070005392A1 (en) * 2002-01-23 2007-01-04 Xerox Corporation Method and system for ordering a consumable for a device
US7822645B2 (en) 2002-01-23 2010-10-26 Xerox Corporation Method and system for ordering a consumable for a device
US20030142338A1 (en) * 2002-01-25 2003-07-31 Xerox Corporation Method and system for shopping for a consumable for a device
US7663770B2 (en) 2002-01-25 2010-02-16 Xerox Corporation Method and system for shopping for a consumable for a device
WO2009014520A1 (fr) * 2007-07-25 2009-01-29 Hewlett-Packard Development Company, L.P. Stabilisation de la concentration d' encre dans un système d'addition d'encre solide
US8588660B2 (en) 2007-07-25 2013-11-19 Hewlett-Packard Development Company, L.P. Stabilization of ink concentration in a solid ink add system

Also Published As

Publication number Publication date
FR95209E (fr) 1970-08-07
DE1772826B2 (de) 1975-09-11
GB1211588A (en) 1970-11-11
DE1772826A1 (de) 1971-06-09

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