Papermaking machine headbox has sandwich construction guide vane incorporating sliding tab moving back and forth by compression spring and steel cable attached to spindle

摘要

A papermaking machine has a headbox with upper and lower cells divided by a horizontal flow guide vane. The vane has upper and lower panels separated by a sliding tab. The tab moves back and forth (11) under the combined influence of a compression spring and a rotating spindle with a steel cable. A papermaking assembly feeds (S) a fibrous suspension (6) through a headbox (1) with upper (Z2) and lower (Z1) cells incorporating vortex generators and discharging through a wide-slit jet (7) defined by upper (8.2) and lower (8.1) walls. The cells are separated by a transverse bearing bar (3) for a twin-lamella flow vane (2). The vane (2) esp. has upper (9, 2) and lower (9.1) parallel panels separated by a gap (A) with a sliding tab (10).The transverse bearing bar (3) has a spindle with a single steel cable attached at two points and linked to the tab. The tab is moved away from the spindle by a compression spring (12.1) and is withdrawn by rotation of the spindle, allowing fore and aft tab movement (Wv).