DEVICE FOR INTERNALLY COATING CONTAINERS
A device for coating containers, in particular bottles, including a vacuum chamber, a plasma generator, and a gas lance having an outlet opening protruding into the container for introducing a material to be deposited on an inner wall of the container. The inside diameter of the gas lance in a region of the outlet opening is enlarged relative to the inside diameter in a main section of the gas lance.
1 . A device ( 1 ) for coating containers ( 18 ), comprising: a vacuum chamber ( 12 ), a plasma generator ( 14 ), and a gas lance with an outlet opening ( 26 ), which, when in operation in the intended manner, protrudes into the container ( 18 ) and serves to introduce a material which is to be deposited on the inner wall of the container ( 18 ), and serves as an antenna for the electromagnetic field orientation in the vacuum chamber, wherein the inside diameter (D) of the gas lance ( 20 ) in the region of the outlet opening ( 26 ) is enlarged relative to the inside diameter (d) in a main section ( 22 ) of the gas lance ( 20 ), wherein the gas lance ( 20 ) is widened in the region of the outlet opening ( 26 ) in a trumpet or conical shape.
2 . The device ( 1 ) according to claim 1 , wherein the inside diameter of the gas lance ( 20 ) in the region of the outlet opening ( 26 ) is greater than the inside diameter in a main section ( 22 ) of the gas lance ( 20 ).
3 . The device ( 1 ) according to claim 1 , wherein the gas lance ( 20 ) consists in the region of the outlet opening ( 26 ) of another material than in the main section ( 22 ).
4 . The device ( 1 ) according to claim 1 , wherein the gas lance ( 20 ) consists at least in part of special steel.
5 . The device ( 1 ) according to claim 1 , wherein the gas lance ( 20 ) consists at least in part of Al 2 O 3 .
6 . The device ( 1 ) according to claim 1 , wherein the gas lance ( 20 ) exhibits at the outlet opening ( 26 ) a diameter (D) which is at least two times larger than the inside diameter (d) of a main section ( 22 ) of the gas lance ( 20 ).
7 . The device ( 1 ) according to claim 1 , wherein the widened part of the gas lance ( 20 ) is arranged in a mounting part ( 32 ), which is held on the main section ( 22 ) of the gas lance ( 20 ) in a replaceable manner.
8 . The device ( 1 ) according to claim 7 , wherein the mounting part ( 32 ) comprises a sleeve ( 34 ), which engages around the main section ( 22 ) and secures the mounting part ( 32 ) on the main section ( 22 ).
9 . The device ( 1 ) according to claim 7 , wherein the inside diameter (dl) of the mounting part ( 32 ), at its end facing the main section ( 22 ) of the gas lance ( 20 ), corresponds to the inside diameter (d) of the main section ( 22 ) of the gas lance ( 20 ).
10 . The device ( 1 ) according to claim 9 , wherein the orientation of the inner wall of the mounting part ( 32 ) is flush with the inner wall of the main section ( 22 ) of the gas lance ( 20 ) at their mutually facing ends.
11 . The device ( 1 ) according to claim 1 , which is configured as a mass coating device with a coating capacity of at least 1,000 containers, and in particular at least 10,000 containers ( 18 ), per hour.
12 . The device ( 1 ) according to a claim 1 , wherein the plasma generator ( 14 ) is a microwave generator.
13 . The device ( 1 ) according to claim 1 , wherein an end edge ( 28 ) of the gas lance ( 20 ) is rounded at the outlet opening ( 26 ).
14 . The device ( 1 ) according to claim 1 , wherein an end edge ( 28 ) of the gas lance ( 20 ) is seamed outwards at the outlet opening ( 26 ).
15 . The device ( 1 ) according to claim 1 , wherein the gas lance ( 20 ) is configured as multi-part, wherein an end section ( 24 ) comprises the outlet opening ( 26 ) and a main section ( 22 ) forms the axially larger part of the gas lance ( 20 ), wherein the end section ( 24 ) is preferably held on the main section ( 22 ) in a replaceable manner.
16 . The device according to claim 1 wherein the plastic containers are made from at least one of Polypropylene, Polyethylene, and Polyethylene terephthalate.