Nitrogen injection assembly for use in an optical fiber coloring and curing apparatus
View Patent ↗A nitrogen injection assembly for use in coloring and curing optical fibers is disclosed. The nitrogen injection assembly includes a cover section and a distribution seal. An optical fiber coated with ink passes from a coating die to a curing chamber via a passageway defined by the cover section and the distribution seal. The distribution seal injects nitrogen into the passageway to keep the coated fiber and the curing chamber substantially free of oxygen. With the distribution seal positioned closer to the curing chamber than the cover section, the apparatus minimizes the risk of leaks in the passageway and the number of required seals.
1. A nitrogen injection assembly for use in an apparatus for coloring and curing optical fibers, the apparatus including a color coating die and a curing chamber, the nitrogen injection assembly comprising:
a cover section separated from the color coating die, the cover section having an interior surface and an exterior surface, the interior surface of the cover section at least partially enclosing a first duct capable of passing a coated optical fiber; and
a distribution seal located closer to the curing chamber than the cover section and having an interior surface, an exterior surface, and an inlet port, the interior surface of the distribution seal at least partially defining a first bore capable of passing the coated optical fiber, the first bore being aligned axially with the first duct of the cover section and including upper and lower cylindrical sections, the upper cylindrical section having a smaller diameter than the lower cylindrical section, wherein the distribution seal includes a circular channel concentric with the upper cylindrical section of the first bore, and wherein the inlet port extends between the exterior surface of the distribution seal and the circular channel and is adapted to allow nitrogen to flow into the first bore.
2. The nitrogen injection assembly of claim 1 , further comprising a lead-in piece positioned between the distribution seal and the cover section, the lead-in piece having an interior surface and an exterior surface, the interior surface of the lead-in piece at least partially enclosing a second bore capable of passing the coated optical fiber between the first duct and the first bore.
3. The nitrogen injection assembly of claim 2 , wherein the lead-in piece has a circular top surface and a circular bottom surface, the second bore having a substantially same diameter at the circular bottom surface as an upper portion of the first bore of the distribution seal.
4. The nitrogen injection assembly of claim 2 , wherein the lead-in piece is affixed to the distribution, substantially preventing entry of ambient atmosphere into the first and second bores.
5. The nitrogen injection assembly of claim 4 , wherein a bottom portion of the lead-in piece forms a flange.
6. The nitrogen injection assembly of claim 2 , wherein the lead-in piece has a circular top surface and a circular bottom surface, a diameter of the top surface being less than a diameter of the bottom surface, the second bore of the lead-in piece extending from the circular top surface to the circular bottom surface.
7. The nitrogen injection assembly of claim 2 , wherein the second bore of the lead-in piece is tapered.
8. The nitrogen injection assembly of claim 2 , wherein the cover section is a flat plate mounted on top of the lead-in piece.
9. The nitrogen injection assembly of claim 1 , wherein the distribution seal includes a plurality of conduits between the circular channel and the lower bore.
10. The nitrogen injection assembly of claim 1 , wherein the cover section is configured to enable access to the coated optical fiber.
11. The nitrogen injection assembly of claim 10 , wherein the separation between the cover section and the color coating die provides access to the coated optical fiber.
12. The nitrogen injection assembly of claim 10 , wherein the cover section comprises a first axial telescope portion and a second axial telescope portion, the second axial telescope portion being slidable at least partially within the first axial telescope portion.
13. The nitrogen injection assembly of claim 10 , wherein the cover section comprises a first radial portion and a second radial portion, the first duct of the cover section being formed by alignment of at least the first and second radial portions.
14. A nitrogen injection assembly for use in an apparatus for coloring and curing optical fibers, the apparatus including a color coating die and a curing chamber, the nitrogen injection assembly comprising:
a cover section separated from the color coating die, the cover section having an interior surface and an exterior surface, the interior surface of the cover section at least partially enclosing a first duct capable of passing a coated optical fiber;
a distribution seal located closer to the curing chamber than the cover section and having an interior surface, an exterior surface, and an inlet port, the interior surface of the distribution seal at least partially defining a first bore capable of passing the coated optical fiber, the first bore being aligned axially with the first duct of the cover section and including upper and lower cylindrical sections, the upper cylindrical section having a smaller diameter than the lower cylindrical section, wherein the distribution seal includes a circular channel concentric with the upper cylindrical section of the first bore and a plurality of conduits extending between the circular channel and the lower bore, and wherein the inlet port extends between the exterior surface of the distribution seal and the circular channel and is adapted to allow nitrogen to flow into the first bore; and
a lead-in piece positioned between the distribution seal and the cover section, the lead-in piece having an interior surface and an exterior surface, the interior surface of the lead-in piece at least partially enclosing a second bore capable of passing the coated optical fiber between the first duct and the first bore, wherein a bottom surface of the lead-in piece covers an open top portion of the circular channel.
15. An apparatus for coloring and curing an optical fiber passing in a downstream direction during manufacture, comprising:
a coloring assembly for depositing an ink on the optical fiber;
a cover section separated from the coloring assembly by an air gap and having an interior surface and an exterior surface, the interior surface of the cover section at least partially enclosing a first duct configured to pass the optical fiber;
a distribution seal positioned downstream from the cover section and having an interior surface, an exterior surface, and an inlet port, the interior surface of the distribution seal at least partially defining a first bore configured to pass the optical fiber, the inlet port extending from the exterior surface of the distribution seal to the interior surface of the distribution seal and being adapted to flow nitrogen into the first bore, wherein the first bore defined by the interior surface of the distribution seal includes upper and lower cylindrical sections, the upper cylindrical section having a smaller diameter than the lower cylindrical section, wherein the distribution seal includes a circular channel concentric with the upper cylindrical section of the first bore, and wherein the inlet port extends between the exterior surface of the distribution seal and the circular channel; and
a UV curing assembly positioned downstream from the distribution seal.
16. The optical fiber coloring and curing apparatus of claim 15 , further comprising a lead-in piece positioned between the distribution seal and the cover section, the lead-in piece having an interior surface and an exterior surface, the interior surface of the lead-in piece at least partially defining a second bore, the second bore being in substantial axial alignment with the first bore of the distribution seal.
17. The optical fiber coloring and curing apparatus of claim 15 , wherein the cover section is configured to enable access to the coated optical fiber.
18. The optical fiber coloring and curing apparatus of claim 17 , wherein the cover section comprises a first axial telescope portion and a second axial telescope portion, the second axial telescope portion being slidable at least partially within the first axial telescope portion.
19. The optical fiber coloring and curing apparatus of claim 17 , wherein the cover section comprises a first half tube section and a second half tube section, the first and second half tube sections each having a substantially semi-circular cross section, the first half tube section and the second half tube section forming the first duct when the cover section is in a closed position.
20. The optical fiber coloring and curing apparatus of claim 17 , further comprising a lead-in piece positioned between the distribution seal and the cover section, the lead-in piece having an interior surface and an exterior surface, the interior surface of the lead-in piece at least partially enclosing a second bore capable of passing the coated optical fiber between the first duct and the first bore, wherein the cover section is a flat plate mounted on top of the lead-in piece.