公开(公告)号：CA992599A

公开(公告)日：1976-07-06

申请号：CA126621

申请日：1971-11-02

Applicant: IBM

Inventor： BRUCE GEORGE D ,  DAVIDGE RONALD V ,  FOWLER RAYMOND L ,  HOBGOOD GEORGE W JR ,  LOCKLAR HENRY C JR ,  VAN CLEAVE GEORGE W

IPC: G03B27/52

公开(公告)号：CA1115329A

公开(公告)日：1981-12-29

申请号：CA321244

申请日：1979-02-08

Applicant: IBM

Inventor： ERNST LARRY M ,  SEIGAL STEVEN D ,  VAN CLEAVE GEORGE W

IPC: G03G21/00 ,  G03G15/00 ,  G03G15/08 ,  G03G15/11 ,  G03G15/22

Abstract: DYNAMIC REFERENCE FOR AN IMAGE QUALITY CONTROL SYSTEM A system for checking copy quality variables within the image area of an electrophotographic machine. During a test cycle, quality is checked by producing sample test areas within the photoconductor image area ordinarily used for producing copies. Reflectance measurements are made on the sample test areas and compared to a dynamically floating reference achieved by a reflectance measurement from a cleaned portion of the photoconductor within the image area. The testing circuit is balanced so that the same reflectance voltage should be generated whether the single reflectivity-sensing device is viewing a sample test area or a cleaned reference area. The system checks for quality variables such as toner concentration, image voltage and an abnormally low reflectance photoconductor and provides a partial check on its own fault-free condition during periods when it is not in use.

公开(公告)号：CA1092342A

公开(公告)日：1980-12-30

申请号：CA269829

申请日：1977-01-17

Applicant: IBM

Inventor： HUBBARD JAMES H ,  VAN CLEAVE GEORGE W

IPC: G03G15/08

Abstract: TONER CONCENTRATION CONTROL APPARATUS A xerographic copying apparatus having a developer operable to present a two component developer mix, i.e. carrier and toner, to the photoconductor's latent electrostatic image, and apparatus for automatically adding virgin toner to the developer as the toner concentration is depleted as a result of toning the photoconductor's image over a period of making a number of copies. Once the need to add toner is indicated, a known, unit quantity of toner is added to the developer. Immediately thereafter, the ability to sense toner concentration is inhibited until the next two photoconductor images have been toned. In the event that low concentration is sensed immediately thereafter, another unit quantity of toner is added, and sensing is again inhibited for the two-copy interval. In the additional event that low concentration is sensed seven consecutive times, each time being separated by a two-copy inhibit interval, a failure latch is set and further operation of the copying apparatus is inhibited. That latter event may be caused by toner exhaustion, failure to feed toner properly, or failure of the concentration sensing means.

公开(公告)号：CA986996A

公开(公告)日：1976-04-06

申请号：CA167866

申请日：1973-03-28

Applicant: IBM

Inventor： VAN CLEAVE GEORGE W

IPC: H02M1/08 ,  G05F1/445 ,  G05F1/455 ,  G05F1/56 ,  G05F1/66

Abstract: A regulating power supply circuit in which the power supplied at the output is controlled by controlling the firing angle of a thyrister switching device in response to changes in a hybrid signal which is indicative of the difference between the RMS value of the output voltage and a desired RMS value. The hybrid signal is formed by summing a feedback current proportional to the absolute load voltage with a reference current proportional to the firing angle of the thyrister on a summing capacitor. Since for any given RMS voltage, the value of the average load voltage varies linearly with the conduction angle over a large range of conduction angles, the phase angle proportional reference current source is utilized to relate the absolute output voltage with the RMS voltage linearly over a wide range of input voltages.