Vibration absorber with high viscous dampening

• US 9,579,730 B2
• Filed: 06/30/2014
• Issued: 02/28/2017
• Est. Priority Date: 06/30/2014
• Status: Active Grant

• Current Assignee: Kennametal Incorporated
• Original Assignee: Kennametal Incorporated
• Inventors: Frota de Souza Filho, Ruy
• Primary Examiner(s): HOWELL, DANIEL W
• Application Number:
  US14/319,643
• Publication Number:
  US 20150375304A1
• Time in Patent Office: 974 Days
• US Class Current: 1/1
• CPC Class Codes: B23B 2250/16 Damping of vibrations
• CPC Class Codes: B23B 27/002 with vibration damping means
• CPC Class Codes: B23B 27/007 for internal turning boring bars B23B29/02, boring heads B23B29/03; milling cutters B23C5/00; reamers B23D77/00
• CPC Class Codes: B23B 29/022 with vibration reducing means
• CPC Class Codes: Y10T 408/76 Tool-carrier with vibration-damping means

Abstract

A tunable or tuned boring tool having a dynamic vibration absorber is provided herein. The boring tool includes a boring bar having a distal portion configured to support a tool, a proximal portion configured for attachment to a support structure of a metalworking machine, and a cylindrical body extending between the proximal portion and the distal portion, having an elongated cavity therein. The boring tool further includes a tuned or tunable absorber inserted in the cavity of the boring bar. The absorber includes an absorber mass, an annular or partially annular support circumscribing each end of the absorber mass for holding the absorber mass within the cavity, and a layer of fluid restricting material surrounding at least a central portion of the absorber mass for dampening vibration of the absorber mass. A method of forming a boring tool with a dynamic vibration absorber is also provided herein.

Claims

1. A tuned or tunable boring tool comprising:

a boring bar having a distal portion configured to support a tool, a proximal portion configured for attachment to a support structure of a metalworking machine, and a cylindrical body extending between the proximal portion and the distal portion, having an elongated cavity therein with fluid sealed within at least a portion of the cavity; and

a tuned or tunable absorber within the cavity of the boring bar, the absorber comprising an absorber mass, an annular or partially annular support circumscribing each end of the absorber mass for holding the absorber mass within the cavity, and a layer of fluid restricting material surrounding at least a central portion of the absorber mass and immersed in the fluid, which in conjunction with the fluid, dampens vibration of the absorber mass,

wherein the layer of fluid restricting material comprises a porous material having a plurality of open cells capable of being filled with fluid.

2. The tuned or tunable boring tool of claim 1, wherein the fluid is natural or synthetic oil.

3. The tuned or tunable boring tool of claim 1, wherein the layer of fluid restricting material is a foam, a gel, a cross-linked polymer, or a porous solid material.

4. The tuned or tunable boring tool of claim 1, wherein the layer of fluid restricting material comprises a non-porous material having a plurality of channels extending through the layer.

5. The tuned or tunable boring tool of claim 4, wherein the plurality of channels are molded in the layer of fluid restricting material.

6. The tuned or tunable boring tool of claim 1, wherein the layer of fluid restricting material comprises a plurality of interconnected strips surrounding portions of the absorber mass to form a plurality of connected annular rings surrounding the outer surface of the mass.

7. The tuned or tunable boring tool of claim 1, wherein the layer of fluid restricting material comprises a strip wrapped around at least a portion of the mass in a helical pattern.

8. The tuned or tunable boring tool of claim 1, further comprising a cutting element attached to the distal end of the bar.

9. The tuned or tunable boring tool of claim 1, wherein the annular or partially annular supports comprise an elastic material.

10. The tuned or tunable boring tool of claim 1, further comprising a tuning mechanism associated with one of the annular or partially annular supports for tuning the absorber to a desired vibration frequency.

11. The tuned or tunable boring tool of claim 1, wherein the absorber mass and vibration absorbing layer are enclosed within a canister within the cavity, wherein the canister is filled with fluid.

12. A tuned boring tool comprising:

a boring bar having a distal portion configured to support a tool, a proximal portion configured for attachment to a support structure of a metalworking machine, and a cylindrical body extending between the proximal portion and the distal portion, having an elongated cavity therein with fluid sealed within at least a portion of the cavity; and

a tuned absorber within the cavity of the boring bar, the absorber comprising an absorber mass and a layer of fluid restricting material surrounding at least a central portion and the opposing ends of the absorber mass and immersed in the fluid, which in conjunction with the fluid, dampens vibration of the absorber mass,

wherein the layer of fluid restricting material comprises a porous material having a plurality of open cells capable of being filled with fluid.

13. A method of forming a tuned or tunable boring bar, the method comprising:

providing a boring bar having a distal portion configured to support a tool, a proximal portion configured for attachment to a support structure of a metalworking machine, and a cylindrical body extending between the proximal portion and the distal portion, having an elongated cavity therein;

providing a tuned or tunable vibration absorber comprising an absorber mass, an annular or partially annular support circumscribing each end of the absorber mass for holding the absorber mass within the cavity, and a layer of fluid restricting material surrounding at least a central portion of the absorber mass;

filling the cavity with fluid;

mounting the vibration absorber into the cavity of the boring bar;

mounting a cutting tool to the distal end of the boring bar; and

securing the proximal end of the boring bar to a mounting structure of a metalworking machine;

wherein, upon vibration of the boring bar, fluid provided within the cavity of the boring bar passes back and forth through the fluid restricting material as the absorber mass vibrates; and

wherein the layer of fluid restricting material comprises a porous material having a plurality of open cells capable of being filled with fluid.

14. The method of claim 13, wherein the layer of fluid restricting material is porous and comprises a sponge, a gel, a foam, or any combination thereof.

15. The method of claim 13, further comprising attaching a tuning mechanism to the boring tool, such that the tuning mechanism compresses the at least one support, thereby tuning the absorber to a desired vibration frequency.

16. A method of forming a tuned boring tool, the method comprising:

providing a boring bar having a distal portion configured to support a tool, a proximal portion configured for attachment to a support structure of a metalworking machine, and a cylindrical body extending between the proximal portion and the distal portion, having an elongated cavity therein;

providing a tuned vibration absorber comprising an absorber mass within the cavity, and a layer of fluid restricting material surrounding at least a central portion and opposing ends of the absorber mass;

filling the cavity with fluid;

mounting the vibration absorber into the cavity of the boring bar;

mounting a cutting tool to the distal end of the boring bar; and

securing the proximal end of the boring bar to a mounting structure of a metalworking machine;

wherein, upon vibration of the boring bar, fluid provided within the cavity of the boring bar passes back and forth through the fluid restricting material as the absorber mass vibrates; and

wherein the layer of fluid restricting material comprises a porous material having a plurality of open cells capable of being filled with fluid.