Patent ID: 6413368
Filing Date: 2002-07-02
Classification: D21F,Y10S

Abstract:
Apparatus for making a fibrous web or tissue comprising:(i) a moving foraminous support; (ii) slurry supply means for supplying an aqueous slurry of fibers maintained at a consistency of from about 0.5 to about 7 weight percent fibers based on the dry weight of the fibers; (iii) foam supply means for supplying a foamed liquid comprising water, air and a surface active agent containing from about 50 to about 80 percent air by volume; (iv) furnish makeup means for combining said aqueous slurry of fibers with said foamed liquid to form a foamed fiber furnish containing from about 50 to about 80 percent air by volume in an amount sufficient to form a foamed fiber furnish containing from about 0.1 to about 3 weight percent fibers based on the dry weight of the fibers, said furnish makeup means including a supply line from said slurry supply means and a supply line from said foam supply means operatively connected to a positive displacement pump, and consistency determining means for measuring the consistency of said aqueous slurry of fibers and flow rate determining means for measuring the flow rate of said aqueous slurry of fibers being operatively connected to said supply line from said slurry supply means; (v) means for depositing said foamed fiber furnish on said foraminous support in an amount sufficient to form a fibrous web; (vi) mass sensitive means for measuring the basis weight of said web; and (vii) furnish consistency control means being operatively connected to and responsive to said flow rate determining means; said mass sensitive means and to said consistency determining means for producing a signal for actuating a valve operatively connected to said supply line from said foam supply means for controlling the flow rate of said aqueous slurry of fiber into said furnish makeup means.