Multi-segment toning shoe for latent image development
AssigneePrecision Image Corporation
InventorsAndreas Bibl, Gene F. Day
Life of this patent
Estimating the term…
Abstract
A toning shoe for applying fluid developer to a latent image on a supported sheet. A drum is the preferred support, with the toning shoe having raised upstream and downstream support rims contacting the sheet, opposed lateral insulating rims spaced very slightly from the sheet or conducting rims contacting the sheet and a recessed multi-segmented electrode further spaced from the sheet. Fluid developer is injected through slits at leading edges of the electrode segments, flows as a thin film between the electrode segments and the sheet and then passes through drains at trailing edges of the electrode segments for collecting and recycling. The shoe moves laterally as the drum rotates so that development occurs in a helical stripe pattern.
Claims21
Apparatus for applying fluid developer to a latent image on a sheet supported by a backing member comprising,
- a shoe having raised peripheral edges and a central recessed area surrounded by said peripheral edges, said peripheral edges including an upstream and a downstream support rim, said central recessed area including a multisegmented electrode with a plurality of substantially uniform electrode segments closely spaced from a supported sheet bearing a latent image stripe, each electrode segment having an upstream side and having a downstream side distant said upstream support rim relative to said upstream side of the electrode segment, said central recessed area having pluralities of developer supplies and drains extending parallel said electrode segments, each electrode segment spaced apart from an adjacent electrode segment by a developer supply and a drain, each supply located at said upstream side of an associated electrode segment and in communication with a supply of fluid developer for applying the developer to the sheet, each drain located at said downstream side of an electrode segment and immediately adjacent a supply with no intervening electrode between the immediately adjacent supply and drain,
- pressure means for injecting fluid developer to each supply and creating a plurality of substantially distinct flows of developer from said upstream sides of said electrode segments toward the associated drain at the downstream side of each electrode segment,
- means for biasing said shoe against said sheet, and
- means for removing excess developer from each said drain and away from said sheet.
A toning shoe for use in an electrostatic printer comprising,
- a frame having opposed upper and lower support rims, a central surface between said support rims and a pair of lateral flat surfaces bounding said central surface,
- two blocks mounted on said lateral flat surface to form lateral rims, and
- a multi-segmented electrode mounted to said central surface, said multi-segmented electrode including a plurality of electrically conductive electrode segments recessed relative to said support rims by a depth of less than ten mils, each of said electrode segments an upper end associated in side-by-side relation with a developer supply slit in communication with a supply of fluid developer, each of said electrode segments having a lower end in side-by-side relation with a drain channel in communication with passageways formed in at least one of said blocks for removing excess developer from said drain channel, the lower end of each electrode segment being distant the upper support rim relative to the upper end of said electrode segment, each electrode segment spaced apart from an adjacent electrode segment by a drain channel and by a developer supply slit, where the drain channel and developer supply slit are immediately adjacent to each other such that no intervening electrode is present between the immediately adjacent developer supply slit and drain channel.
An apparatus for applying fluid developer to a latent image on a sheet supported on a backing member, comprising:
- a drum having a round circumferential surface capable of supporting a sheet carrying an electrostatic latent image,
- a toning shoe having a toning surface matching a region of the circumferential surface of the drum, said toning shoe having raised peripheral edges including upstream and downstream support rims in contact with said sheet, said toning surface defined by a central recessed area surrounded by said raised peripheral edges and further defined by a plurality of substantially uniform electrode segments closely spaced from said sheet, each electrode segment having an upstream side and having a downstream side distant said upstream support rim relative to said downstream side, each electrode segment spaced apart from adjacent electrode segments by a developer supply and a drain, said supplies parallelly disposed such that each supply is at an upstream side of an electrode segment, said drains parallelly disposed such that each drain is at a downstream side of an electrode segment and is immediately adjacent to the supply associated with the electrode segment downstream said drain with no intervening electrode between the immediately adjacent supply and drain,
- pressure means for injecting fluid developer to each supply, thereby creating a plurality of distinct flows of developer over said electrode segments towards said drains, said flows being uniform in direction from said upstream sides to said downstream sides of the electrode segments,
- means for biasing said shoe against said sheet,
- means for moving said toner shoe relative to said drum and across said sheet, and
- means for removing excess developer from each said drain and away from said sheet.
Dependencies are inferred from the claim text.