US4383498A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for applying magnetic toner to a magnetic transport roll
Assignee: Proterial Ltd
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Filing: 1980-09-18
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Granted: 1983-05-17
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Expires: 2000-09-18
Abstract
Abstract This invention relates to apparatus for developing electrostatic latent images, and, more particularly, to apparatus and method for controlling the feed of magnetic toner between a toner supply hopper and a magnetic transport roll.
Inventors
- 👤 Keitaro Yamashita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:27
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/09
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
242 words
In apparatus for supplying magnetic toner to an image-developing zone of a copying machine including a non-magnetic cylindrical shell, a magnet roll rotatable within the shell, the magnet roll including on its surface a plurality of elongated magnets parallel to the axis of the roll and alternating in polarity, and a hopper for holding a supply of lower portion, the improvement comprising: a non-magnetic member having a plane surface for guiding toner from said discharge port to the vicinity of the surface of the shell, said member being substantially tangential to the surface of the cylindrical shell, said member having an end portion in the vicinity of said shell and said end portion forming a doctor gap with said shell for determining the depth of toner supplied to said shell from said surface, wherein said magnetic toner is supplied to a surface of said non-magnetic member from the toner discharge port of said hopper and the opposite surface to said surface of the non-magnetic member is facing to said non-magnetic cylindrical shell, said non-magnetic member being positioned upstream of the point of tangency relative to the direction of rotation of the magnet roll, and wherein said discharge port is positioned in the vicinity of a circular line which divides an area where magnetic toner particles tend to be attracted to the cylindrical shell by magnetic force and an area where magnetic toner particles tend to self-rotate by rotation of said magnet roll.
Claim 2
Dependent Claim
242 words
In apparatus for supplying magnetic toner to an image-developing zone of a copying machine including a non-magnetic cylindrical shell, a magnet roll rotatable within the shell, the magnet roll including on its surface a plurality of elongated magnets parallel to the axis of the roll and alternating in polarity, and a hopper for holding a supply of lower portion, the improvement comprising: a non-magnetic member having a plane surface for guiding toner from said discharge port to the vicinity of the surface of the shell, said member being substantially tangential to the surface of the cylindrical shell, said member having an end portion in the vicinity of said shell and said end portion forming a doctor gap with said shell for determining the depth of toner supplied to said shell from said surface, wherein said magnetic toner is supplied to a surface of said non-magnetic member from the toner discharge port of said hopper and the opposite surface to said surface of the non-magnetic member is facing to said non-magnetic cylindrical shell, said non-magnetic member being positioned upstream of the point of tangency relative to the direction of rotation of the magnet roll, and wherein said discharge port is positioned in the vicinity of a circular line which divides an area where magnetic toner particles tend to be attracted to the cylindrical shell by magnetic force and an area where magnetic toner particles tend to self-rotate by rotation of said magnet roll.
Claim 3
Dependent Claim
26 words
The improvement of claim 1, wherein the distance between said magnet roll and said discharge port along said surface is between about 11 and 13 millimeters.
Claim 4
Dependent Claim
17 words
The improvement of claim 1, wherein said non-magnetic member is integral with a wall of said hopper.
Claim 5
Dependent Claim
12 words
The improvement of claim 1 or 3, wherein said plate is horizontal.
Claim 6
Dependent Claim
25 words
The improvement of claim 1, wherein the magnetic flux density on said non-magnetic surface at said discharge port is between about 50 and 80 gauss.
Claim 7
Dependent Claim
19 words
The improvement of claim 1 wherein said discharge port is located within about 5 mm of said circular line.
Claim 8
Dependent Claim
19 words
The improvement of claim 6 wherein said discharge port is located within about 3 mm of said circular line.
Claim 9
Dependent Claim
25 words
The improvement of claim 1 wherein said doctor gap between said end portion of said non-magnetic member and the non-magnetic shell is about 2 mm.
Claim 10
Dependent Claim
232 words
In apparatus for supplying magnetic toner to an image-developing zone of a copying machine including a non-magnetic cylindrical shell, a magnet roll rotatable within the shell, the magnet roll including on its surface a plurality of elongated magnets parallel to the axis of the roll and alternating in polarity; a hopper for holding a supply of magnetic toner, the hopper having a toner discharge port at its lower portion; and a non-magnetic guide plate for transporting toner from the discharge port to the surface of the non-magnetic shell under the influence of the magnets, the improvement comprising: means for forming a dam-like accumulation of toner on the guide plate for regulating the amount of toner transported from the discharge port to the shell, said dam-forming means including (a) the guide plate having a guide surface being aligned in a plane substantially tangent to the surface of the non-magnetic shell, the guide plate being positioned upstream of the point of tangency relative to the direction of rotation of the magnet roll; (b) the discharge port being located to feed toner to said guide surface substantially at the limit of the distance from the magnet roll for attracting toner to the shell along said guide surface; and (c) said guide surface having a terminal part proximate the shell surface forming a doctor blade for determining the depth of toner applied to the shell surface.
Claim 11
Dependent Claim
232 words
In apparatus for supplying magnetic toner to an image-developing zone of a copying machine including a non-magnetic cylindrical shell, a magnet roll rotatable within the shell, the magnet roll including on its surface a plurality of elongated magnets parallel to the axis of the roll and alternating in polarity; a hopper for holding a supply of magnetic toner, the hopper having a toner discharge port at its lower portion; and a non-magnetic guide plate for transporting toner from the discharge port to the surface of the non-magnetic shell under the influence of the magnets, the improvement comprising: means for forming a dam-like accumulation of toner on the guide plate for regulating the amount of toner transported from the discharge port to the shell, said dam-forming means including (a) the guide plate having a guide surface being aligned in a plane substantially tangent to the surface of the non-magnetic shell, the guide plate being positioned upstream of the point of tangency relative to the direction of rotation of the magnet roll; (b) the discharge port being located to feed toner to said guide surface substantially at the limit of the distance from the magnet roll for attracting toner to the shell along said guide surface; and (c) said guide surface having a terminal part proximate the shell surface forming a doctor blade for determining the depth of toner applied to the shell surface.
Claim 12
Dependent Claim
65 words
The improvement as in claim 9 wherein (i) the discharge port is located between about 11 mm and 13 mm from the surface of the shell, (ii) the magnetic flux density at the discharge port is between about 50 gauss and 80 gauss, and (iii) the distance between the terminal part of said guide surface and the surface of the shell is about 2 mm.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-05-16 | 1986-11-15 | 1987-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-16 | 1990-11-15 | 1991-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-16 | 1994-11-15 | 1995-05-17 | $7700.00 | Window Closed / Lapsed |