Dryer-fuser apparatus and method for high speed electrophotographic printing device
AssigneeAM International, Inc.
InventorsMark F. Duchesne, Richard A. Gaspar
Life of this patent
Estimating the term…
Abstract
A dryer-fuser apparatus and method are provided to evaporate volatile, flammable carrier liquid from and to fuse solids color-imparting particles to a travelling web of paper in a high speed electrophotographic printing process. Volatiles from the dryer are vented to a catalytic converter, with heat recovered from the catalytic converter being recycled to supply heat to the dryer-fuser. An electric resistance heater may be used to supply heat during system start up and during such times when auxiliary heat is required. Regulation of the amount of venting is provided and is dependent upon the concentration of flammable volatiles present in the dryer.
Claims17
In an electrostatic printing process of the type wherein a color imparting liquid toner dispersion comprising a volatile, flammable carrier liquid and solid color imparting toner particles is applied to a traveling web of paper or the like to form the desired image, a method of drying the web in a hot air dryer by evaporating the carrier liquid from the web and mixing the volatilized carrier with the hot air, comprising:
- directing the web through the dryer;
- supplying a stream of hot air into the dryer;
- suspending the traveling web in a cushion of the hot air while passing the web through the dryer;
- withdrawing the combined volatilized carrier and hot air from the dryer with a variable speed exhaust fan;
- and
- measuring the content of the variable speed exhaust fan in response to such measured content of carrier volatiles to control the amount of venting.
Apparatus for drying a web of paper or the like that has been wetted with a liquid toner dispersion comprising a volatile, flammable carrier liquid and solids toner particles, said apparatus comprising:
- a dryer including a hot air supply manifold and means defining a dryer chamber around said manifold;
- a supply conduit connected to said supply manifold for supplying hot air to said dryer;
- conveyer means for moving the web along a path through said dryer chamber past said manifold whereby substantially all carrier liquid on the web is volatilized to mix in said dryer chamber with the hot air from said manifold;
- means for suspending the web in an air cushion while the web is moved through said dryer chamber;
- vent means connected to said dryer chamber for venting the mixture of hot air and volatilized carrier from said dryer chamber;
- a variable speed exhaust fan connected to withdraw the mixture of air and volatilized carrier through said vent means;
- means for measuring the content of volatilized carrier in said dryer chamber;
- and
- means responsive to said measuring means for regulating the speed of said exhaust fan to control the amount of mixture flowing through said vent means.
Dependencies are inferred from the claim text.