Vibration damping support

• US 3,923,414 A
• Filed: 07/16/1973
• Issued: 12/02/1975
• Est. Priority Date: 07/16/1973
• Status: Expired due to Term

• Current Assignee: Gte Valeron Corp. (Verizon Communications Inc.)
• Original Assignee: David Alan Hopkins
• Inventors: Hopkins, David Alan
• Primary Examiner(s): Yost, Frank T.
• Assistant Examiner(s): Bilinsky, Z. R.
• Application Number:
  US05/379,438
• Time in Patent Office: 869 Days
• Field of Search: 408/143 188/1B 279/83 82/DIG.9
• US Class Current: 408/143
• CPC Class Codes: B23B 29/022 with vibration reducing means
• CPC Class Codes: B23B 29/03 Boring heads
• CPC Class Codes: B23B 31/1076 with conical ends
• CPC Class Codes: Y10S 82/904 Vibrating method or tool
• CPC Class Codes: Y10T 279/17821 Set screw
• CPC Class Codes: Y10T 408/76 Tool-carrier with vibration-damping means

Abstract

A vibration damping support suitable for a boring bar comprising a shank member, multiple parallel bores extending axially of said boring bar in one end of the shank member and high inertia mass members positioned in each axial bore with a slight circumferential clearance, the mass members being free to move transversely to the shank axis within the circumferential clearance provided. The shank may include a separable extension member or tool nose piece and a connecting member with interengaging retention means for drawing the shank and extension into rigid engagement.

Claims

1. A machining vibration damping support, comprising;

a shank member, a plurality of longitudinal bores in said shank member having cross sectional areas comprising a minor fraction of the cross sectional area of said shank member, the material of said shank member surrounding said bores providing an integral structurally rigid network, at least one mass member in each longitudinal bore having a circumference only slightly less than said bore and sized for axial as well as circumferential clearance therewithin, said mass members being freely movable within said clearance, and said longitudinal bores being substantially filled by said mass members with said axial clearance allowing substantially frictionless movement relative to any adjacent mass members and said shank member.

2. The support of claim 1 wherein the axes of said bores are parallel to the axis of said shank member.

3. The support of claim 2 wherein said bores are cylindrical.

4. The support of claim 3 wherein said mass members are cylindrical.

5. The support of claim 4 wherein all the mass members of at least one bore have equal diameters.

6. The support of claim 4 adapted for light or medium machining with circumferential clearance in the order of 0.002 to 0.003 inch diameter difference.

7. The support of claim 4 adapted for heavy machining with circumferential clearance in the order of 0.004 to 0.006 inch diameter difference.

8. The support of claim 1 wherein the density of said mass members is substantially greater than the density of said shank member.

9. The support of claim 8 including sintered tunsten carbide mass members.

10. The support of claim 1 wherein said clearance is occupied with a low viscosity to negligible fluid.

11. The support of claim 1 wherein at least the surfaces of said bores and said mass members are of wear resistant, substantially nondeformable material.

12. The support of claim 1 wherein said shank member has a cutting tool installed at one end wherein said bores and mass members are concentrated at the cutting end of said shank member.

13. The support of claim 12 wherein the remainder of said shank member is of solid construction.

14. The support of claim 1, including a separable extension member mounted on said shank member, interengaging pilot means at the interface of said shank and extension members, connecting bores in each of said extension and shank members, a connecting member extending through said connecting bores serving as an abutment for confining said mass members, and retention means engaging each of said extension and shank members, said retention means being adapted to draw said extension and shank members into rigid engagement.

15. The support of claim 14 wherein said retention means includes adjustable cam means.

16. The support of claim 15 wherein said adjustable cam means includes a conical depression and interengaging cone point screw.

17. A vibration damping extension member wherein the improvement comprises;

a plurality of longitudinal bores in said extension member, at least one mass member in each longitudinal bore having a circuMference only slightly less than said bore and sized for axial as well as circumferential clearance therewithin, said mass members freely moveable within said clearance, and said longitudinal bores being substantially filled by said mass members with said axial clearance allowing substantially frictionless movement relative to adjacent mass members and said extension member.