Incremental rotary rolling mill and method

Patent metadata

Field	Value
Publication number	US-11077477-B2
Application number	US-201716341163-A
Country	US
Kind code	B2
Filing date	Oct 6, 2017
Priority date	Oct 11, 2016
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

A rolling mill system for Incremental rotary shaping of an elongated workpiece is provided that includes first and second workpiece holders. A support frame has a track with the first and second workpiece holders being movably associated with the track, the workpiece holders and an associated workpiece being movable in unison along the track. A radial chuck is mounted to the frame that includes a plurality of jaws that are movable radially inwardly and outwardly. Each jaw has a tool mounted thereto that is rotatable about an axis of rotation, with the axis of rotation of each tool being oriented at a skew angle relative to the longitudinal axis of a workpiece. A source of electric current and an electrically conductive flow path are provided for flowing electrical current through a workpiece. A controller is provided that is configured to control the operation of each of the first motor, second motor and third motor, and to control the flow of current flowing through the tools to the workpiece.

First claim

The invention claimed is:

1. A rolling mill system for incremental rotary shaping of an elongated workpiece having first and second ends and having a longitudinal axis extending therebetween, the system comprising:
a) a first workpiece holder configured to secure the first end of a workpiece thereto;
b) a second workpiece holder configured to secure the second end of the workpiece thereto so that the longitudinal axis of the workpiece extends between the first and second workpiece holders;
c) a support frame having an input end and an output end and supporting a track, the first and second workpiece holders being movably associated with the track;
d) a first motor mounted to the support frame and operatively connected to one of the first and second workpiece holders for moving the first and second workpiece holders and an associated workpiece in unison along the track between the input end and the output end of the support frame;
e) a chuck mounted to the frame having a plurality of jaws movable radially inward and outward relative to the longitudinal axis of the workpiece, each jaw having a tool mounted thereto rotatable about an axis of rotation, the axis of rotation of each tool being oriented at a skew angle relative to the longitudinal axis of a workpiece mounted between the first and second workpiece holders;
f) a second motor associated with the chuck and operatively connected to the jaws for simultaneously moving the jaws toward or away from the longitudinal axis of a workpiece;
g) a third motor operatively connected to each tool for simultaneously rotating each tool relative to its associated jaw;
h) a source of electric current and an electrically conductive flow path connected to each of the tools and the first workpiece holder for flowing electrical current through a workpiece mounted between the first and second workpiece holders; and
i) a controller configured to control the operation of each of the first motor, second motor and third motor, and to control the flow of current flowing through the tools to a workpiece; and
wherein the third motor is operatively connected to each of the tools by a slewing ring rotatably mounted in a housing secured to the support frame, the slewing ring having gear teeth and the motor having a shaft with a pinion gear mounted thereto in engagement with the teeth of the slewing ring for rotation of the slewing ring, a rotatable stub shaft associated for each tool mounted in the housing, each stub shaft having a pinion gear mounted thereto engaging the gear teeth of the slewing ring, and a drive shaft extending between each tool and one of the stub shafts.

2. The system of claim 1 wherein each tool comprises a workpiece-engaging surface having a convex shape.

3. The system of claim 2 wherein the workpiece-engaging surface is removably secured to its associated tool.

4. The system of claim 1 further comprising an elongated mandrel having a first end rotatably mounted to the frame adjacent the input end, the mandrel being sized in diameter to be received within a tubular workpiece and sized in length to extend through the workpiece during movement of the workpiece between the input end and the output end of the system.

5. The system of claim 1 wherein the controller is configured to individually control the current to each of the tools.

6. The system of claim 1 wherein the controller includes an operator input for identifying material characteristics and geometrical configuration of the workpiece, and the controller automatically operates the motors and controls the current flow through the workpiece based on the input.

7. A method for incremental rotary shaping of an elongated workpiece having first and second ends and having a longitudinal axis extending therebetween with the system of claim 1 comprising: a) mounting the workpiece to the first and second workpiece holders b) moving the jaws of the chuck radially inwardly to bring the workpiece engaging surfaces of the tools into contact with the workpiece; c) rotating each of the tools through a single motor; d) moving the workpiece relative to the tools in a forming pass from a first position to a second position; e) moving the jaws of the chuck radially outwardly to move the workpiece engaging surfaces of the tools away from contact with the workpiece; f) moving the workpiece relative to the tools in a return pass from the second position to the first position; and g) repeating steps b)-f), as needed, to achieve a desired shape for the workpiece.

8. The method of claim 7 further comprising flowing current through the workpiece as the workpiece moves in the forming pass from the first position to the second position.

9. The method of claim 8 further comprising flowing current through the tools to the workpiece as the workpiece moves in the forming pass from the first position to the second position.

10. The method of claim 8 further comprising flowing current through the workpiece from the first end of the workpiece to the second end of the workpiece as the workpiece moves in the forming pass from the first position to the second position.

11. The method of claim 9 further comprising before step a), mounting an elongated mandrel to the support frame so that the mandrel extends through the workpiece and the first and second workpiece holders during movement of the workpiece between the first and second positions.

12. The method of claim 9 wherein the workpiece is placed under tension as it moves from the first position to the second position.

13. The method of claim 9 wherein a required current density is applied through the workpiece dependent upon the material of the workpiece.

14. The system of claim 1 wherein the skew angle between the axis of each tool and the longitudinal axis of the workpiece is from 30° to 60°.

15. The system of claim 2 wherein the workpiece-engaging surface of each tool has a maximum diameter of X and has a radius of curvature of approximately 2X.

16. A rolling mill system for incremental rotary shaping of an elongated workpiece having first and second ends and having a longitudinal axis extending therebetween, the system comprising:
a) a first workpiece holder configured to secure the first end of a workpiece thereto;
b) a second workpiece holder configured to secure the second end of the workpiece thereto so that the longitudinal axis of the workpiece extends between the first and second workpiece holders;
c) a support frame having an input end and an output end and supporting a track, the first and second workpiece holders being movably associated with the track;
d) a first motor mounted to the support frame and operatively connected to one of the first and second workpiece holders for moving the first and second workpiece holders and an associated workpiece in unison along the track between the input end and the output end of the support frame;
e) a chuck mounted to the frame having a plurality of jaws movable radially inward and outward relative to the longitudinal axis of the workpiece, each jaw having a tool mounted thereto rotatable about an axis of rotation, the axis of rotation of each tool being oriented at a skew angle relative to the longitudinal axis of a workpiece mounted between the first and second workpiece holders;
f) a source of electric current and an electrically conductive flow path connected to each of the tools and the first workpiece holder for flowing electrical current through a workpiece mounted between the first and second workpiece holders; and
g) a controller configured to control the operation of each of the first motor and to co

Assignees

• Univ Northwestern

Inventors

• Zeng Qiang
• Ehmann Kornel
• Ng Man Kwan
• Cao Jian

Classifications

• B21B2275/04

  Roll speed · CPC title

• B21B39/02

  Feeding or supporting work; Braking or tensioning arrangements {, e.g. threading arrangements} · CPC title

• B21B2275/10

  Motor power; motor current · CPC title

• B21B2267/06

  Roll diameter · CPC title

• B21B1/20

  in a non-continuous process,(e.g. skew rolling, i.e. planetary cross rolling) · CPC title