Deep rolling tool and method

Patent metadata

Field	Value
Publication number	US-10786883-B2
Application number	US-201615385648-A
Country	US
Kind code	B2
Filing date	Dec 20, 2016
Priority date	Dec 20, 2016
Publication date	Sep 29, 2020
Grant date	Sep 29, 2020

Abstract

An embodiment of a tool assembly includes a spring-loaded shaft assembly disposed along a first axis, a hub, and a roller disk. The hub is connected to a distal end of the spring-loaded shaft assembly. The hub has an upper hub portion adjacent to the distal end of the spring-loaded shaft assembly aligned with the first axis, and a lower hub portion extending along a second axis. The second axis forms an angle relative to the first axis. The roller disk is joined to the lower portion of the hub, and has a working surface about its perimeter. The roller disk is rotatable about the second axis parallel to the second portion of the hub. The working surface includes a profile along its width such that an effective radius of the roller disk varies along a width thereof.

First claim

The invention claimed is:

1. A non-axisymmetric tool assembly comprising:
a spring-loaded shaft assembly disposed along a first axis;
a hub connected to a distal end of the spring-loaded shaft assembly, the hub having an upper hub portion adjacent to the distal end of the spring-loaded shaft assembly aligned with the first axis, and a lower hub portion extending along a second axis, the second axis forming an angle relative to the first axis;
a roller disk joined to the lower portion of the hub, the roller disk having a non-axisymmetric working surface about its perimeter and being rotatable about the second axis parallel to the second portion of the hub, the working surface including a profile along its width such that an effective radius of the roller disk varies nonuniformly along a width thereof, the profile corresponding to a shape of a junction between an airfoil portion and a dovetail root portion of a fan blade workpiece; and
means for generating and varying an applied force along the first axis such that the applied force is transferred through the spring-loaded shaft assembly and the hub to the non-axisymmetric working surface of the roller disk according to a programmed load profile that is configured to impart a compressive stress along the junction without deforming the workpiece;
wherein the applied force is varied and monitored in real time according to the programmed load profile and feedback from a load cell.

2. The assembly of claim 1 , wherein the shaft assembly comprises a flexible shaft.

3. The assembly of claim 1 , wherein the shaft assembly comprises:
a solid shaft to restrain movement only along the first axis; and
a resilient element disposed at a distal end of the shaft assembly proximate to the hub.

4. The assembly of claim 3 wherein the solid shaft comprises a linear bearing arranged along the first axis.

5. The assembly of claim 3 , wherein the resilient element comprises a plurality of stacked Belleville washers.

6. The assembly of claim 3 , wherein the resilient element comprises a diaphragm spring.

7. The assembly of claim 1 , and further comprising a tool holder mounted to a proximal end of the shaft assembly.

8. The assembly of claim 1 , wherein the upper hub portion and the lower hub portion define a right angle.

9. The assembly of claim 8 , wherein the roller disk is rotatable about the second axis perpendicular to the first axis.

10. The assembly of claim 1 , wherein the working surface of the roller disk is crowned nonuniformly from a center to opposing first and second edges.

11. A method comprising:
supporting a workpiece in a fixture, the workpiece having a first nonplanar surface: and
performing a first rolling operation on the first nonplanar surface, the first rolling operation comprising:
applying a downward force to a proximal end of a spring-loaded non-axisymmetric deep rolling tool shaft assembly aligned with a first axis, the downward force applied along the first axis such that the downward force is transferred through the shaft assembly to a hub disposed at a distal end of the shaft assembly, the hub having an upper hub portion adjacent to the distal end of the spring-loaded shaft assembly aligned with the first axis, and a lower hub portion extending along a second axis, the second axis forming an angle relative to the first axis;
transmitting the transferred downward force from an upper portion of the hub aligned with the first axis to a lower portion of the hub parallel to a second axis, the second axis forming an angle relative to the first axis, about which a roller disk is supported by one or more bearings, such that a resulting compressive force is applied to the first nonplanar surface of the workpiece via a working surface of the roller disk, the roller disk having a non-axisymmetric working surface about its perimeter and being rotatable about the second axis parallel to the second portion of the hub, the working surface including a profile along its width such that an effective radius of the roller disk varies nonuniformly along a width thereof, the profile corresponding to a shape of a junction between an airfoil portion and a dovetail root portion of a fan blade workpiece; and
generating and varying an applied force along the first axis such that the applied force is transferred through the spring-loaded shaft assembly and the hub to the non-axisymmetric working surface of the roller disk according to a programmed load profile that is configured to impart a compressive stress along the junction without deforming the workpiece;
wherein the applied force is varied and monitored in real time according to the programmed load profile and feedback from a load cell.

12. The method of claim 11 , wherein the resulting compressive force applied to the first nonplanar surface varies nonuniformly along the width of the working surface.

13. The method of claim 12 , wherein the working surface of the roller disk is crowned nonuniformly from a center to opposing first and second edges.

14. The method of claim 11 , wherein the deep rolling tool shaft assembly comprises:
a solid shaft extending along the first axis to restrain movement only along the first axis; and
a resilient element disposed at a distal end of the solid shaft adjacent to the hub.

15. The method of claim 14 , wherein the resilient element comprises a plurality of stacked Belleville washers.

16. The method of claim 14 , wherein the solid shaft is supported by a linear bearing.

17. The method of claim 11 , and further comprising connecting the proximal end of the shaft to an automated machine.

18. The method of claim 11 and further comprising using the tool to perform a second rolling operation on a second nonplanar surface of the workpiece.

19. The method of claim 17 , wherein the second nonplanar surface is directly opposite the first nonplanar surface.

20. The method of claim 11 , wherein the roller disk is rotatable about the second axis perpendicular to the first axis.

Assignees

• United Technologies Corp

Inventors

• Hawkes Justin R
• Rampone Joseph C
• Kuczek Andrzej Ernest
• El-Wardany Tahany Ibrahim
• Salva Randy P
• Clavette Patrick Louis
• Garosshen Thomas J

Classifications

• B24B27/0038

  with the grinding tool mounted at the end of a set of bars · CPC title

• B21D39/023

  using rollers · CPC title

• Y10S901/41

  Tool · CPC title

• B23P9/02

  Treating or finishing by applying pressure, e.g. knurling (B23P9/04 takes precedence) · CPC title

• B25J15/0019

  End effectors other than grippers · CPC title