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US3962992A Expired / Lapsed US ⏱️ 0.0 years remaining

Device for developing an electrostatically charged image

Assignee: Toshiba Corp
•
Filing: 1974-10-25
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Granted: 1976-06-15
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Expires: 1994-10-25
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Abstract

Abstract A device develops an electrostatically charged image formed on a photoelectroconductive layer with toner particles bearing a residual magnetization. The toner particles are provided on a vessel and in an alternating magnetic field to be rotated and repeatedly rebounded while charged, so as to be attracted onto the charged image.

Inventors

  • 👤 Michiyasu Takagi
  • 👤 Toshihiko Oguchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 14:17
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09; G03G15/0921

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 113 words
In combination, a device for developing an electrostatically charged image formed on a photoelectroconductive layer, comprising a supporting member disposed at a predetermined interval below the photoelectroconductive layer and including a vessel made of magnetic flux passing material, toner particles placed on the supporting member and bearing a residual magnetization, and alternating magnetic field generating means for applying an alternating magnetic field to said residually magnetized toner particles to cause the latter to be rotated, while repeatedly rebounding on the supporting member, causing the toner particles to be electrically charged to permit the charged toner particles to be deposited onto the electrostatically charged image and a quantity of said residually magnetized toner particles.
Claim 2
Dependent Claim 113 words
In combination, a device for developing an electrostatically charged image formed on a photoelectroconductive layer, comprising a supporting member disposed at a predetermined interval below the photoelectroconductive layer and including a vessel made of magnetic flux passing material, toner particles placed on the supporting member and bearing a residual magnetization, and alternating magnetic field generating means for applying an alternating magnetic field to said residually magnetized toner particles to cause the latter to be rotated, while repeatedly rebounding on the supporting member, causing the toner particles to be electrically charged to permit the charged toner particles to be deposited onto the electrostatically charged image and a quantity of said residually magnetized toner particles.
Claim 3
Dependent Claim 40 words
In a combination of developing device and toner particles according to claim 1, in which said alternating magnetic field generating means includes an electromagnet disposed below the supporting member and an AC source for applying AC voltages to the electromagnet.
Claim 4
Independent Claim 125 words
A device for developing an electrostatically charged image formed on a photoelectroconductive layer, comprising a supporting member disposed at a predetermined interval below the photoelectroconductive layer, toner particles placed on the supporting member and bearing a residual magnetization, and alternating magnetic field generating means for applying an alternating magnetic field to the toner particles to cause the latter to be rotated, while repeatedly rebounding on the supporting member, causing the toner particles to be electrically charged to permit the charged toner particles to be deposited onto the electrostatically charged image including an electromagnet disposed below the supporting member and an AC source for applying AC voltages to the electromagnet, and wherein said supporting member includes an open-topped vessel made of a non-magnetic and electroconductive material.
Claim 5
Independent Claim 125 words
A device for developing an electrostatically charged image formed on a photoelectroconductive layer, comprising a supporting member disposed at a predetermined interval below the photoelectroconductive layer, toner particles placed on the supporting member and bearing a residual magnetization, and alternating magnetic field generating means for applying an alternating magnetic field to the toner particles to cause the latter to be rotated, while repeatedly rebounding on the supporting member, causing the toner particles to be electrically charged to permit the charged toner particles to be deposited onto the electrostatically charged image including an electromagnet disposed below the supporting member and an AC source for applying AC voltages to the electromagnet, and wherein said supporting member includes an open-topped vessel made of a non-magnetic and electroconductive material.
Claim 6
Dependent Claim 45 words
In a combination of developing device and toner particles according to claim 1, in which said alternating magnetic field generating means includes a plurality of electromagnets disposed below the supporting member and a power source circuit for applying an AC voltage to the respective electromagnets.
Claim 7
Independent Claim 155 words
A device for developing an electrostatically charged image formed on a photoelectroconductive layer, comprising a supporting member disposed at a predetermined interval below the photoelectroconductive layer, toner particles placed on the supporting member and bearing a residual magnetization, and alternating magnetic field generating means for applying an alternating magnetic field to the toner particles to cause the latter to be rotated, while repeatedly rebounding on the supporting member, causing the toner particles to be electrically charged to permit the charged toner particles to be deposited onto the electrostatically charged image including a plurality of electromagnets disposed below said supporting member and a power source circuit for applying an AC voltage to the respective electromagnets, said plurality of electromagnets being divided into at least one group consisting of three electromagnets and said power source circuit including a three phase power source for applying to the three electromagnets AC voltages which are phase-shifted 120° from each other.
Claim 8
Independent Claim 155 words
A device for developing an electrostatically charged image formed on a photoelectroconductive layer, comprising a supporting member disposed at a predetermined interval below the photoelectroconductive layer, toner particles placed on the supporting member and bearing a residual magnetization, and alternating magnetic field generating means for applying an alternating magnetic field to the toner particles to cause the latter to be rotated, while repeatedly rebounding on the supporting member, causing the toner particles to be electrically charged to permit the charged toner particles to be deposited onto the electrostatically charged image including a plurality of electromagnets disposed below said supporting member and a power source circuit for applying an AC voltage to the respective electromagnets, said plurality of electromagnets being divided into at least one group consisting of three electromagnets and said power source circuit including a three phase power source for applying to the three electromagnets AC voltages which are phase-shifted 120° from each other.
Claim 9
Independent Claim 171 words
A device for developing an electrostatically charged image formed on a photoelectroconductive layer, comprising a supporting member disposed at a predetermined interval below the photoelectroconductive layer, toner particles placed on the supporting member and bearing a residual magnetization, and alternating magnetic field generating means for applying an alternating magnetic field to the toner particles to cause the latter to be rotated, while repeatedly rebounding on the supporting member, causing the toner particles to be electrically charged to permit the charged toner particles to be deposited onto the electrostatically charged image including a plurality of electromagnets disposed below said supporting member and a power source circuit for applying an AC voltage to the respective electromagnets, said plurality of electromagnets being divided into at least one group consisting of two electromagnets, and said power source circuit including a single phase AC source and a circuit for connecting the electromagnets to the source so that one of the electromagnets of the group is supplied with an AC voltage which is phase shifted by π/2.
Claim 10
Independent Claim 171 words
A device for developing an electrostatically charged image formed on a photoelectroconductive layer, comprising a supporting member disposed at a predetermined interval below the photoelectroconductive layer, toner particles placed on the supporting member and bearing a residual magnetization, and alternating magnetic field generating means for applying an alternating magnetic field to the toner particles to cause the latter to be rotated, while repeatedly rebounding on the supporting member, causing the toner particles to be electrically charged to permit the charged toner particles to be deposited onto the electrostatically charged image including a plurality of electromagnets disposed below said supporting member and a power source circuit for applying an AC voltage to the respective electromagnets, said plurality of electromagnets being divided into at least one group consisting of two electromagnets, and said power source circuit including a single phase AC source and a circuit for connecting the electromagnets to the source so that one of the electromagnets of the group is supplied with an AC voltage which is phase shifted by π/2.
Claim 11
Dependent Claim 29 words
In a combination of developing device and toner particles according to claim 1, in which said toner is a mixture of a magnetized material and a colored synthetic resin.
Claim 12
Dependent Claim 26 words
In a combination of developing device and toner particles according to claim 7, in which said toner has a residual magnetization of at least 10 gauss.
Claim 13
Dependent Claim 22 words
A developing device according to claim 5, in which said electromagnets are driven to change the direction of a rotating magnetic field.
Claim 14
Dependent Claim 22 words
A developing device according to claim 6, in which said electromagnets are driven to change the direction of a rotating magnetic field.
Claim 15
Dependent Claim 23 words
In a combination of a developing device and toner particles according to claim 1, in which said vessel is made of electroconductive materials.

References Cited (Backward Citations)

US2910963A Cited
US3117891A Cited
US3611991A Cited
US3839029A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-06-15 1979-12-15 1980-06-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-06-15 1983-12-15 1984-06-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-06-15 1987-12-15 1988-06-15 $7700.00 Window Closed / Lapsed

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