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US5006897A Expired / Lapsed US ⏱️ 0.0 years remaining

Determination of charge-to-mass ratio

Assignee: NexPress Solutions LLC
•
Filing: 1990-07-02
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Granted: 1991-04-09
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Expires: 2010-07-02
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Abstract

Abstract In electrostatographic apparatus, the ratio of toner particle electrostatic charge-to-toner particle mass and the development rate are determined by providing a piezo device positioned to interact with toner particles. The device is periodically electrically biased to attract toner particles, and the frequency shift of the piezo device due to the mass of attracted toner particles is detected. The electrostatic charge buildup on the electrode due to the attracted toner particles is detected to determine the mass of toner. The potential on the device may be changed periodically from a potential which attracts toner to a potential which repels toner to clean the device.

Inventors

  • 👤 Donald S. Rimai
  • 👤 Joseph F. Laukaitis
  • 👤 Mark Zaretsky
  • 👤 Bruno Primerano

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 14:46
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0851

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 71 words
Electrostatographic apparatus comprising means for developing a latent electrostatic image by the application of toner particles, said apparatus comprising: a piezo device having an electrode capacitively coupled to another member and positioned to interact with toner particles used in the apparatus; means for periodically electrically biasing the electrode to attract toner particles; and means for detecting the frequency shift of the piezo device due to the mass of attracted toner particles.
Claim 2
Dependent Claim 71 words
Electrostatographic apparatus comprising means for developing a latent electrostatic image by the application of toner particles, said apparatus comprising: a piezo device having an electrode capacitively coupled to another member and positioned to interact with toner particles used in the apparatus; means for periodically electrically biasing the electrode to attract toner particles; and means for detecting the frequency shift of the piezo device due to the mass of attracted toner particles.
Claim 3
Dependent Claim 48 words
Electrostatographic apparatus as set forth in claim 1 wherein said means for periodically electrically biasing the electrode to attract toner particles is adapted to periodically change the potential on the electrode from a potential which attracts toner to a potential which repels toner to periodically clean the electrode.
Claim 4
Dependent Claim 101 words
Electrostatographic apparatus comprising means for developing a latent electrostatic image by the application of toner particles, and means for measuring the ratio of toner particle electrostatic charge-to-toner particle mass, said measuring means comprising: a piezo device having an electrode capacitively coupled to another member and positioned to interact with toner particles used in the apparatus; means for periodically electrically biasing the electrode to attract toner particles; means for detecting the electrostatic charge buildup on the electrode due to the attracted toner particles; and means for detecting the frequency shift of the piezo device due to the mass of attracted toner particles.
Claim 5
Dependent Claim 101 words
Electrostatographic apparatus comprising means for developing a latent electrostatic image by the application of toner particles, and means for measuring the ratio of toner particle electrostatic charge-to-toner particle mass, said measuring means comprising: a piezo device having an electrode capacitively coupled to another member and positioned to interact with toner particles used in the apparatus; means for periodically electrically biasing the electrode to attract toner particles; means for detecting the electrostatic charge buildup on the electrode due to the attracted toner particles; and means for detecting the frequency shift of the piezo device due to the mass of attracted toner particles.
Claim 6
Dependent Claim 36 words
Electrostatographic apparatus with said measuring means as set forth in claim 3 wherein said electrostatic charge buildup detecting means and said frequency shift detecting means produce simultaneous signals which are used to produce a charge-to-mass signal.
Claim 7
Dependent Claim 25 words
Electrostatographic apparatus as set forth in claim 4 wherein said electrostatic charge buildup detecting means is adapted to measure the rate of said charge buildup.
Claim 8
Dependent Claim 27 words
Electrostatographic apparatus as set forth in claim 5 further comprising means, responsive to the measured rate of charge buildup, for determining the rate of toner mass deposition.
Claim 9
Dependent Claim 26 words
Electrostatographic apparatus as set forth in claim 6 wherein the determined rate of toner mass deposition and the charge-to-mass signal are used to determine toner concentration.
Claim 10
Dependent Claim 52 words
Electrostatographic apparatus with said measuring means as set forth in claim 3 wherein said means for periodically electrically biasing the electrode to attract toner particles is adapted to periodically change the potential on the electrode from a potential which attracts toner to a potential which repels toner to periodically clean the electrode.
Claim 11
Dependent Claim 148 words
Electrostatographic apparatus with (1) a plurality of adjustable process control parameters, (2) means for developing a latent electrostatic image by the application of toner particles, and (3) means for adjusting at least one of the process control parameters in accordance with a signal characteristic of the ratio of electrostatic charge-to-toner particle mass of toner particles applied to the latent image, said apparatus comprising: a piezo device having an electrode capacitively coupled to another member and positioned to interact with toner particles used in the apparatus; means for periodically electrically biasing the electrode to attract toner particles; means for detecting the electrostatic charge buildup on the electrode due to the attracted toner particles; means for detecting the frequency shift of the piezo device due to the mass of attracted toner particles; and means for producing a signal characteristic of the ratio of electrostatic charge-to-toner particle mass of toner particles.
Claim 12
Dependent Claim 148 words
Electrostatographic apparatus with (1) a plurality of adjustable process control parameters, (2) means for developing a latent electrostatic image by the application of toner particles, and (3) means for adjusting at least one of the process control parameters in accordance with a signal characteristic of the ratio of electrostatic charge-to-toner particle mass of toner particles applied to the latent image, said apparatus comprising: a piezo device having an electrode capacitively coupled to another member and positioned to interact with toner particles used in the apparatus; means for periodically electrically biasing the electrode to attract toner particles; means for detecting the electrostatic charge buildup on the electrode due to the attracted toner particles; means for detecting the frequency shift of the piezo device due to the mass of attracted toner particles; and means for producing a signal characteristic of the ratio of electrostatic charge-to-toner particle mass of toner particles.
Claim 13
Dependent Claim 36 words
Electrostatographic apparatus with said measuring means as set forth in claim 9 wherein said electrostatic charge buildup detecting means and said frequency shift detecting means produce simultaneous signals which are used to produce a charge-to-mass signal.
Claim 14
Dependent Claim 52 words
Electrostatographic apparatus with said measuring means as set forth in claim 9 wherein said means for periodically electrically biasing the electrode to attract toner particles is adapted to periodically change the potential on the electrode from a potential which attracts toner to a potential which repels toner to periodically clean the electrode.

References Cited (Backward Citations)

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US4026643A Cited
US4314242A Cited
US4425871A Cited
US4615606A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-04-08 1994-10-08 1995-04-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-04-08 1998-10-08 1999-04-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-04-08 2002-10-08 2003-04-09 $7700.00 Window Closed / Lapsed

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