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US4987453A Expired / Lapsed US ⏱️ 0.0 years remaining

Development rate controller

Assignee: NexPress Solutions LLC
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Filing: 1990-02-01
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Granted: 1991-01-22
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Expires: 2010-02-01
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Abstract

Abstract Apparatus and method for controlling the development rate of an electrostatic photocopying machine. An electrode plate is positioned adjacent to the toning brush to form a capacitive circuit in which a portion of the dielectric is the toner mixture used in developing images in the machine. Reversing polarities are applied to the electrode plate to alternately make it attract and repel toner. During the attracting or developing polarity, the transient behavior of the toning current is detected and this transient response is used to determine the development rate of the apparatus. In the specific embodiment described, the transient characteristic detected is the time required for the charging current to decay to a predetermined value.

Inventors

  • 👤 Joseph F. Laukaitis

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 15:47
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/50; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0851

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 97 words
Apparatus for controlling the development rate of an electrostatographic device using a powder toner, said apparatus comprising: an electrode capacitively coupled to another member and suitably positioned to interact with toner used in the device; means for applying potentials to the electrode and the other member; means for charging the polarity of the potential applied to the electrode; means for determining the time required for a charging current, produced when the polarity is changed, to decay to a predetermined value; and means for converting the determined time into signals for controlling the development rate of the device.
Claim 2
Dependent Claim 97 words
Apparatus for controlling the development rate of an electrostatographic device using a powder toner, said apparatus comprising: an electrode capacitively coupled to another member and suitably positioned to interact with toner used in the device; means for applying potentials to the electrode and the other member; means for charging the polarity of the potential applied to the electrode; means for determining the time required for a charging current, produced when the polarity is changed, to decay to a predetermined value; and means for converting the determined time into signals for controlling the development rate of the device.
Claim 3
Dependent Claim 23 words
The development rate controller of claim 1 wherein the other member is a cylindrical toning brush which supports toner and magnetic carrier particles.
Claim 4
Dependent Claim 32 words
The development rate controller of claim 1 wherein the potential on the electrode is charged from a potential which repels toner to a potential which attracts toner to produce the charging current.
Claim 5
Dependent Claim 32 words
The development rate controller of claim 1 wherein the polarity charging means includes a reversible switching means which is activated to reverse the polarity applied to the electrode and the other member.
Claim 6
Dependent Claim 28 words
The development rate controller of claim 1 wherein the determining means counts pulses for the measured time and provides the number of pulses counted to the converting means.
Claim 7
Dependent Claim 20 words
The development rate controller of claim 1 wherein the development rate is controlled by changing the concentration of the toner.
Claim 8
Dependent Claim 20 words
The development rate controller of claim 1 wherein the development rate is controlled by changing the change on the toner.
Claim 9
Dependent Claim 26 words
The development rate controller of claim 1 wherein the development rate is controlled by changing the image writing exposure on a photosensitive member in the device.
Claim 10
Independent Claim 62 words
A method of controlling at least one development rate parameter of an electrostatographic device which uses a powered toner, said method including the steps of: producing a charging current which is responsive to characteristics of the toner; measuring the time needed for the charging current to decay to a predetermined value; and controlling the development rate parameter based upon the measured time.
Claim 11
Independent Claim 62 words
A method of controlling at least one development rate parameter of an electrostatographic device which uses a powered toner, said method including the steps of: producing a charging current which is responsive to characteristics of the toner; measuring the time needed for the charging current to decay to a predetermined value; and controlling the development rate parameter based upon the measured time.
Claim 12
Dependent Claim 42 words
The development controlling method of claim 9 wherein the charging current is produced by applying a potential to an electrode with a polarity which attracts the toner, and wherein the polarity applied to the electrode is periodically reversed for cleaning the electrode.
Claim 13
Dependent Claim 33 words
The development controlling method of claim 9 wherein the time measuring includes the steps of: detecting when the charging current begins; and detecting when the charging current thereafter decays to a predetermined value.
Claim 14
Dependent Claim 20 words
The development controlling method of claim 9 wherein the development rate is changed by altering the concentration of the toner.
Claim 15
Dependent Claim 20 words
The development controlling method of claim 9 wherein the development rate is charged by altering the change on the toner.
Claim 16
Dependent Claim 26 words
The development controlling method of claim 9 wherein the development rate is changed by altering the image writing exposure on a photosensitive member in the device.
Claim 17
Dependent Claim 179 words
Apparatus for controlling one or more parameters which effect the development rate of an electrostatographic device using a powdered toner which is applied to a photosensitive member by a cylindrical brush member around which the toner is deposited, said apparatus comprising: an electrode capacitively coupled to the brush member to effectively form a capacitor, said electrode being positioned to interact with the toner on the brush member; means for applying a potential to the electrode with a polarity which repels the toner from the electrode; means for applying a potential to the electrode with a polarity which attracts the toner to the electrode; means for determining the time required for the charge on the capacitor to attain a predetermined magnitude after the electrode begins to attract toner; means for converting the determined time into signals for controlling at least one of said parameters; and means for alternating the polarity of the potential on the electrode with respect to the brush member, thereby allowing the time measurements and controlling functions to occur several times during the operation of the device.
Claim 18
Dependent Claim 179 words
Apparatus for controlling one or more parameters which effect the development rate of an electrostatographic device using a powdered toner which is applied to a photosensitive member by a cylindrical brush member around which the toner is deposited, said apparatus comprising: an electrode capacitively coupled to the brush member to effectively form a capacitor, said electrode being positioned to interact with the toner on the brush member; means for applying a potential to the electrode with a polarity which repels the toner from the electrode; means for applying a potential to the electrode with a polarity which attracts the toner to the electrode; means for determining the time required for the charge on the capacitor to attain a predetermined magnitude after the electrode begins to attract toner; means for converting the determined time into signals for controlling at least one of said parameters; and means for alternating the polarity of the potential on the electrode with respect to the brush member, thereby allowing the time measurements and controlling functions to occur several times during the operation of the device.
Claim 19
Independent Claim 80 words
A method of controlling at least one development rate parameter of an electrostatographic device which uses a powdered toner, said method including the steps of: applying a charging potential to members which form a capacitor, with the capacitance being responsive to characteristics of the toner; measuring the time needed for the charge on the capacitor to reach a predetermined value after the charging potential is applied; and controlling the development rate parameter based at least partially upon the measued time.
Claim 20
Independent Claim 80 words
A method of controlling at least one development rate parameter of an electrostatographic device which uses a powdered toner, said method including the steps of: applying a charging potential to members which form a capacitor, with the capacitance being responsive to characteristics of the toner; measuring the time needed for the charge on the capacitor to reach a predetermined value after the charging potential is applied; and controlling the development rate parameter based at least partially upon the measued time.

References Cited (Backward Citations)

US4382420A Cited
US4678317A Cited
US4706032A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-01-21 1994-07-23 1995-01-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-01-21 1998-07-23 1999-01-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-01-21 2002-07-23 2003-01-22 $7700.00 Window Closed / Lapsed

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