System and method for straightening and elongating a glass core rod

Patent metadata

Field	Value
Publication number	US-10538455-B2
Application number	US-201715790469-A
Country	US
Kind code	B2
Filing date	Oct 23, 2017
Priority date	Oct 23, 2017
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

A lathe-based system may include chucks to retain a glass core rod, an arm, a slip joint, an actuator system, and a control system. The slip joint may couple the arm and a first chuck in fixed relation against relative axial motion with respect to an axis of rotation. The slip joint may also couple the arm and the first chuck in two-dimensionally movable relation with respect to a plane normal to the axis of rotation. The actuator system may be configured to two-dimensionally adjust a position of the first chuck in the plane. The control system may measure straightness of the glass core rod and control the actuator system in response to optical measurements of the straightness. In this manner, the system may straighten the glass core rod. The system may simultaneously elongate the glass core rod as it straightens the glass core rod.

First claim

What is claimed is:

1. A system, comprising:
a first chuck having a first chuck axis of rotation and configured to retain a first end of a glass core rod in an orientation wherein a longitudinal axis of the glass core rod is substantially aligned with the first chuck axis of rotation;
an arm having an arm axis substantially aligned with the first chuck axis of rotation;
a slip joint coupling the arm and the first chuck in fixed relation against relative axial motion with respect to the first chuck axis of rotation and connecting the arm and the first chuck in two-dimensionally movable relation with respect to a plane normal to the first chuck axis of rotation;
an actuator system coupled to the arm and configured to two-dimensionally adjust a position of the first chuck in the plane; and
a control system having an optical sensing system configured to measure straightness of the glass core rod, the control system configured to control the actuator system in response to optical measurements of the straightness of the glass core rod.

2. The system of claim 1 , wherein the slip joint comprises a body fixedly connected to the first chuck, a retaining cavity in the body having a cavity diameter in the plane, and a pin in the cavity having a pin diameter in the plane less than the cavity diameter, the arm extending from the pin through an opening in the body having an opening diameter less than the cavity diameter and less than the pin diameter.

3. The system of claim 2 , wherein:
the retaining cavity has a cylindrical shape; and
the pin has a cylindrical shape.

4. The system of claim 3 , wherein the actuator system comprises:
a frame connected to the arm; and
at least three actuator motors spaced at equidistant intervals about a periphery of the body, each actuator motor having a pushrod controllably extendable to displace the body a controllable distance with respect to the lathe axis of rotation.

5. The system of claim 4 , wherein the pushrod comprises a threaded rod extendable in response to rotation of a corresponding actuator motor.

6. The system of claim 5 , wherein the frame has a cylindrical cup shape, and the at least three actuator motors are mounted to the frame.

7. The system of claim 1 , further comprising a torch configured to traverse a path parallel to the first chuck axis of rotation.

8. The system of claim 7 , wherein the torch and the optical sensing system are mounted on a carriage.

9. The system of claim 1 , wherein the optical sensing system comprises a laser and a photosensor, the laser configured to direct a beam toward the glass core rod, the photosensor configured to receive a beam partially obstructed by the glass core rod.

10. The system of claim 1 , further comprising an elongation lathe having a first lathe chuck rotatably mounted with respect to a lathe axis of rotation, a second lathe chuck rotatably mounted with respect to the lathe axis of rotation, a rotational drive system, and an elongation drive system, the first lathe chuck configured to retain an end of the arm, the second lathe chuck configured to retain a second end of the glass core rod, the rotational drive system configured to rotate the first and second lathe chucks, the elongation drive system configured to translate the first lathe chuck along the lathe axis of rotation.

11. A system, comprising:
a lathe having a first chuck and a second chuck each rotatably mounted with respect to a lathe axis of rotation, the first chuck configured to retain a first end of a glass core rod, the second chuck configured to retain a second end of the glass core rod, a rotational drive system configured to rotate the second chuck;
an arm having an arm axis substantially aligned with the lathe axis of rotation;
a slip joint coupling the arm and the first chuck in fixed relation against relative axial motion with respect to the lathe axis of rotation and connecting the arm and the first chuck in two-dimensionally movable relation with respect to a plane normal to the lathe axis of rotation;
an elongation drive system coupled to the arm and configured to translate the first chuck along the lathe axis of rotation via the slip joint;
an actuator system coupled to the arm and configured to two-dimensionally adjust a position of the first chuck in the plane via the slip joint; and
a control system having an optical sensing system configured to measure straightness of the glass core rod, the control system configured to control the actuator system in response to optical measurements of the straightness of the glass core rod.

12. The system of claim 11 , wherein the slip joint comprises a body fixedly connected to the first chuck, a retaining cavity in the body having a cavity diameter in the plane, and a pin in the cavity having a pin diameter in the plane less than the cavity diameter, the arm extending from the pin through an opening in the body having an opening diameter less than the cavity diameter and less than the pin diameter.

13. The system of claim 12 , wherein:
the retaining cavity has a cylindrical shape; and
the pin has a cylindrical shape.

14. The system of claim 13 , wherein the actuator system comprises:
a frame connected to the arm; and
at least three actuator motors spaced at equidistant intervals about a periphery of the body, each actuator motor having a pushrod controllably extendable to displace the body a controllable distance with respect to the lathe axis of rotation.

15. The system of claim 14 , wherein the pushrod comprises a threaded rod extendable in response to rotation of a corresponding actuator motor.

16. The system of claim 15 , wherein the frame has a cylindrical cup shape, and the at least three actuator motors are mounted to the frame.

17. The system of claim 11 , further comprising a torch configured to traverse a path parallel to the lathe axis of rotation.

18. The system of claim 11 , wherein the torch and the optical sensing system are mounted on a carriage.

19. The system of claim 11 , wherein the optical sensing system comprises a laser and an optical sensor, the laser configured to direct a beam toward the glass core rod, the optical sensor configured to receive a beam partially obstructed by the glass core rod.

20. A method, comprising:
mounting a glass core rod in a lathe by retaining a first end of the glass core rod in a first chuck rotatably mounted with respect to a lathe axis of rotation and a second end of the glass core rod in a second chuck rotatably mounted with respect to the lathe axis of rotation;
rotating the glass core rod in the lathe;
measuring straightness of the glass core rod using an optical sensing system;
heating a portion of the glass core rod;
two-dimensionally adjusting a position of the first chuck in a plane normal to the lathe axis of rotation using an actuator system and a control system responsive to measurements received from the optical sensing system; and
elongating the glass core rod using an elongation drive system substantially simultaneously with two-dimensionally adjusting the position of the first chuck, wherein a slip joint transfers axial motion produced by the elongation drive system to the first chuck while the first chuck is rotating.

21. The method of claim 20 , wherein the actuator system adjusts the position of the first chuck using at least three actuator motors spaced at equidistant intervals about a periphery of the first chuck, each actuator motor having a pushrod controllably extendable to displace the first

Assignees

• Ofs Fitel Llc
• Ofs Fltel Llc

Inventors

• Edmundson Mark L

Classifications

• G01B11/306

  for measuring evenness · CPC title

• C03B37/01861 Primary

  Means for changing or stabilising the diameter or form of tubes or rods · CPC title

• C03B23/047

  by drawing ({C03B23/091} , C03B37/025 takes precedence) · CPC title

• C03B23/045

  Tools or apparatus specially adapted for re-forming tubes or rods in general, e.g. glass lathes, chucks (C03B23/043 takes precedence) · CPC title

• G01N21/958

  Inspecting transparent materials {or objects, e.g. windscreens (for conveyed flat sheet or rod G01N21/896)} · CPC title