Claims
- 1. An element for removing a film of excess liquid from the surface of a coating applicator and then diverting said film of excess liquid away from said surface, comprising:an element support member; blade member and a liquid deflector member, wherein said blade member having one end disposed in said element support member and an active end extending from said element support member for engaging said coating applicator, said blade member arranged at a predetermined angle θt with said coating applicator and having a point of contact therewith and wherein said liquid deflector member having one end disposed directly adjacent said one end of said blade member in said element support member and an opposite end with an active face, arranged proximate to said contact point of said blade member, extending downwardly and away from said blade member such that said active face is inclined at a predetermined angle θs relative to said active end of said blade member such that said predetermined angle θs is equal to or greater than said predetermined angle θt thereby resulting in the excess coating doctored by said blade member from said coating applicator being captured by said deflector member.
- 2. The element recited in claim 1 wherein said active face of said liquid deflector member is generally contoured away from said surface of said coating applicator.
- 3. The element recited in claim 1 wherein said active face of said liquid deflector member is generally contoured towards said surface of said coating applicator.
- 4. The element recited in claim 1 wherein said active face of said liquid deflector member is generally planar.
- 5. The element recited in claim 1 wherein said blade member has an underside that extends from said point of contact to said active face of said liquid deflector member, said underside defining a predetermined clearance.
- 6. The element recited in claim 5 wherein said predetermined clearance for a predetermined inclination θh, is predicted by the relationship: clearance∝(q2g)1/3·f,wherein: f is a monotonically increasing function of the Reynolds' Number (Re), given by Re≡q ρμ;q is flow rate of deflected liquid (per unit width of coating); μ is viscosity of coating liquid; ρ is density of coating liquid; and g is acceleration due to gravity.
- 7. The element recited in claim 5 wherein said predetermined clearance is in the range between about 0.64 cm (0.25 in) and 1.9 cm (0.75 in).
- 8. The element recited in claim 5 wherein a generally arcuate path is formed between said underside of said blade member and said active face of said liquid deflector member.
- 9. The element recited in claim 5 wherein a generally obtuse angular path is formed between said underside of said blade member and said active face of said liquid deflector member.
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is related to U.S. application Ser. No. 09/465,202, filed Dec. 15, 1999, by Ramasubramaniam Hanumanthu, et al., and entitled, “Apparatus For Coating A Web.”
US Referenced Citations (7)
Foreign Referenced Citations (3)
Number |
Date |
Country |
22 64 119 |
Jul 1974 |
DE |
84 01 569 |
Jul 1988 |
DE |
97 38797 |
Oct 1997 |
WO |