Global Patent Index - EP 1030823 A1

EP 1030823 A1 2000-08-30 - DRAW CONSTANT DOWNFEED PROCESS

Title (en)

DRAW CONSTANT DOWNFEED PROCESS

Title (de)

KONSTANTES UNTERZIEHVERFAHREN

Title (fr)

PROCEDE DE DISTRIBUTION SUPERIEURE CONSTANTE PAR ETIRAGE

Publication

EP 1030823 A1 (EN)

Application

EP 98946905 A

Priority

  • US 9818785 W
  • US 5966297 P

Abstract (en)

[origin: WO9915470A1] Optical fiber (14) is drawn from a preform (10) that is fed to a furnace at a constant downfeed rate. The optical fiber (14) is drawn by a tractor (20) at a rate of at least 10 meters per second and the tractor (20) is allowed to vary the draw speed of the fiber (14) based on the fiber diameter as measured by a diameter monitor (15) during the draw processing in order to maintain a relatively constant fiber diameter. Maintaining the preform downfeed rate constant even at high draw rates in excess of 20 meters per second does not adversely effect the draw process and is believed to reduce or eliminate oscillations in the draw control loop that can cause variations in the core shape during fiber formation, resulting in reduced PMD and improved MFD uniformity.

IPC 1-7 (main, further and additional classification)

C03B 37/02; C03B 37/025; C03B 37/07

IPC 8 full level (invention and additional information)

G02B 6/00 (2006.01); C03B 37/025 (2006.01); C03B 37/027 (2006.01)

CPC (invention and additional information)

C03B 37/0253 (2013.01); C03B 2205/06 (2013.01); C03B 2205/40 (2013.01); C03B 2205/42 (2013.01); C03B 2205/44 (2013.01); C03B 2205/72 (2013.01)

Designated contracting state (EPC)

DE ES FI FR GB IT NL

EPO simple patent family

WO 9915470 A1 19990401; AU 738625 B2 20010920; AU 9381798 A 19990412; BR 9812674 A 20000822; CA 2301033 A1 19990401; CN 1119301 C 20030827; CN 1271334 A 20001025; EP 1030823 A1 20000830; EP 1030823 A4 20001227; ID 24850 A 20000824; JP 2001517598 A 20011009

INPADOC legal status


2004-06-23 [18D] DEEMED TO BE WITHDRAWN

- Effective date: 20031223

2002-10-16 [17Q] FIRST EXAMINATION REPORT

- Effective date: 20020903

2000-12-27 [A4] SUPPLEMENTARY SEARCH REPORT

- Effective date: 20001109

2000-12-27 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A4

- Designated State(s): DE ES FI FR GB IT NL

2000-12-27 [RIC1] CLASSIFICATION (CORRECTION)

- Free text: 7C 03B 37/027 A, 7C 03B 37/07 B

2000-08-30 [17P] REQUEST FOR EXAMINATION FILED

- Effective date: 20000420

2000-08-30 [AK] DESIGNATED CONTRACTING STATES:

- Kind Code of Ref Document: A1

- Designated State(s): DE ES FI FR GB IT NL