| 摘要 |
The present invention relates to a double-coating cup for coating an optical fibre with two protective layers simultaneously. The cup includes a body provided with an axially extending, frusto-conical boring whose largest diameter is located on the fibre-inlet side, a die holder firmly pressed into the body and having a frusto-conical outer surface which corresponds to the boring, and two die nozzles inserted in the die holder and functioning to apply the two layers of coating material. According to the invention, the body (1) has two first diametrically opposed first coating-material inlet channels (4) spaced at a first axial distance from the inlet side, and two second diametrically opposed second coating-material inlet channels (5) spaced at a second axial distance from the inlet side. The die holder (8) has a frusto-conical boring (10) whose largest diameter lies on the fibre inlet-side, a first cylindrical boring (11) which is a continuation of the conical boring, a first shoulder (12), a second cylindrical boring (13), a second shoulder (14), and a third cylindrical boring (15), wherein the outer surface (9) of the die holder has first ring-shaped slots (17) and first radial borings (18) which connect with the ring-shaped slots (17) and which open into the junction between the frusto-conical boring (10) and the first cylindrical boring (11), and second ring-shaped slots (19) which connect with second radial borings (20) which open into the second cylindrical boring (13). A guide die (21) is inserted into the conical boring (10) of the die holder and includes an outwardly extending part (25) in the end-wall (26) of the die. A first cylindrical die nozzle (27) having a frusto-conical recess (28) is inserted in the first cylindrical boring (11) in a manner such as to form a first coating-material gap or slot (30) between the die nozzle (27) and the guide die (21). A cylindrical intermediate guide die (34) is inserted against the first shoulder (12) and has a frusto-conical outwardly projecting part (37) in the end-wall (38) of the die. A second cylindrical die nozzle (39) having a frusto-conical recess (40) is positioned in the second cylindrical boring (13) and in abutment with the second shoulder (14) in a manner such as to form a second coating-material gap or slot (43) between the die nozzle (39) and the intermediate guide die (34). The die nozzle has distribution channels (44) which connect with the second radial borings (20) and which distribute coating material around the fibre coated with the first coating material and therewith centre the fibre in respective dies. <IMAGE> |
