Turning bar for moving web
AssigneeCrown Zellerbach Corporation
InventorImants Reba
Life of this patent
Estimating the term…
Abstract
Apparatus for providing an air cushion to support web material during turning thereof and including means defining two plenums providing a flow path for pressurized gas prior to the gas exiting from a slit adjacent a generally curved fluid flow attachment surface. The dual plenum arrangement results in an even air distribution at the location of the slit thus contributing to web stability and control as the web floats on a cushion of air comprised of the pressurized air and ambient air along the generally curved fluid flow attachment surface due to the Coanda effect.
Claims12
Apparatus for supporting web material as said web material is transported and redirected from a predetermined first direction of movement to a predetermined second direction of movement, said apparatus comprising:
- elongated first plenum defining means having an inlet for the admission of pressurized gas into said first plenum and an outlet positioned along the length of said elongated first plenum defining means for allowing egress of said pressurized gas from said first plenum;
- an elongated housing surrounding and spaced from said elongated first plenum defining means to define a second plenum therewith in fluid-flow communication with said first plenum through said outlet, said elongated housing at least partially defining a slit providing fluid-flow communication between said second plenum and the ambient atmosphere;
- and
- means defining a generally curved fluid flow attachment surface positioned immediately adjacent said slit whereby pressurized gas exiting from said slit will attach itself to said generally curved fluid flow attachment surface due to the Coanda effect and provide along with ambient air entrained by said exiting gas a gaseous support cushion for said web during transport and redirection thereof.
Dependencies are inferred from the claim text.