Back to results
US 4,322,158 AGranted
Thermal film development apparatus
AssigneeMicron Corporation
InventorsRonald J. Frias, Roger A. Gross, David Jagielski
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeMicron Corporation
InventorsRonald J. Frias, Roger A. Gross, David Jagielski
Estimating the term…
A compact thermal developer is mounted in a microfiche reader printer. The developer is a two-stage unit having a pair of roller-heater units located to pass on exposed copy sheet in one direction through succeeding stages in an over-and-under movement to develop the copy and produce a flat hard copy. Each roller-heater unit includes a roller having an outer thin friction coating rotatably supported within an arcuate recess portion of a heater bar. The heater bar and roller are arranged with roller biased toward the heater to grasp the copy sheet. The roller includes a thin aluminum tube supported by heat insulating end members mounted on a shaft with a floating connection to support the tube with a permission relative axial movement to compensate for different coefficients of thermal expansion. A thin silicone rubber coating on the tube establishes positive sheet movement while providing sufficient thermal transmission to present a thermally light background member. The roller-heater units shafts are mounted in plastic end caps supports. The microfiche reader includes a double-faced mirror unit pivotally mounted to transmit the microfiche image onto a front viewing screen or alternately to an exposure frame structure. A small mirror is pivoted from the image path in the alternate position. A copy paper roll is coupled to powered transfer and cutter assembly for moving the paper into and from the exposure frame to the developer.
A thermal developer for supplying heat to a copy sheet having a thermally developable surface material for copying of the original material and said copy sheet subject to being set in a curved shaped by the development heat for said surface material, comprising a first and second roller unit, each of said units including a roller unit mounted with the axis of the roller units in a common plane and having an entrance means and exit means to and from said roller units substantially in said common plane, a first heat source having a heat radiating surface substantially matching the curvature of said first roller unit and located to one side of said plane in nesting relationship to the first roller unit, and a second heat source having a heat radiating surface substantially matching the curvature of said second roller units and located in nesting relationship to said second roller unit, said second heat source being located to the opposite side of said plane from said first heat source, said heat sources being operable to heat said copy sheet to the developing temperature, and said second roller unit being closely mounted to said first roller unit to receive the copy sheet from said first roller unit whereby each copy sheet moves continuously in one direction through said developer.
A thermal developer suitable for supplying heat to a copy sheet having a thermally developable surface material for copying of original material, comprising a hollow drive roller unit including an inner heat distributing roller for rapidly distributing heat and establishing a uniform temperature throughout the length of the roller unit, said roller being formed of heat conductive metal establishing rapid heat transfer throughout the roller and having open ends, a thin outer friction material intimately attached to the outer surface of said roller, said friction material adapted to frictionally grasp said sheet and transport said sheet and simultaneously provide rapid heat transfer to said heat distributing element, a rotating support unit rotatably supporting of the roller unit for rotation about a relatively fixed axis, a heat source having a heat radiating surface substantially matching the curvature of said roller unit, means mounting said source in opposed relation to said roller unit and including means biasing the source into engagement with the roller and permitting limited movement of the source relative to the roller, said friction material being selected and constructed to establish rapid heat transfer whereby said roller functions as a heat distributing means and thereby creates a uniform hot background to said copy sheet, and said rotating support unit supporting the roller at the opposite ends and including a thermal insulating plastic end cap secured to each end of said roller and defining continuous end thermal barriers at the opposite ends of said roller to minimize heat loss from said roller through the rotating support unit.
A thermal developer suitable for supplying heat to a copy sheet having a thermally developable surface material for copying of original material, comprising a hollow drive roller unit including an inner heat distributing roller for rapidly distributing heat and establishing a uniform temperature throughout the length of the roller unit, a thin outer friction material intimately attached to the outer surface of said roller, said friction material adapted to frictionally grasp said sheet and transport said sheet and simultaneously provide rapid heat transfer to said heat distributing element, a shaft rotatably supporting the roller unit for rotation about a relatively fixed axis, a heat source having a heat radiating surface substantially matching the curvature of said roller unit, means mounting said source in opposed relation to said roller unit and including means biasing the source into engagement with the roller and permitting limited movement of the source relative to the roller, said friction material being selected and constructed to establish rapid heat transfer whereby said roller functions as a heat distributing means and thereby creates a uniform hot background to said copy sheet, said roller unit being supported at the opposite ends by thermal insulating end members to define end thermal barriers at the opposite ends of said roller unit and minimizes heat loss therefrom, said end members include central shaft hubs spaced from said distributing roller, a supporting shaft coupling means for rotatably locking said hubs to said shaft means and for permitting limited relative axial movement of the end members and said shaft means.
A reader-printer apparatus having means for projecting an image from a film carrier for selective viewing a film image and copying said image on a hard copy sheet, comprising a housing, an optical projection system for projecting the image onto the housing and including a double faced mirror movable mounted between a first position locating a first side of the mirror into image path for projecting the image onto a viewing screen and a second position for projecting the image onto copy exposure support, a source of image copy sheet material and including means to successively move portions thereof into the exposure support, a thermal developer having first and second developing stages mounted to transport the copy sheet in one continuing direction therethrough, each stage having a driver roller means nested within a heating source, the roller means of the first and second stages being mounted with the axis of the roller means in a common plane and with the heat sources of the first and second stages located to the opposite sides of said plane, and means to rotate said roller means to transport the copy sheet.
Dependencies are inferred from the claim text.