Efficient multi-directional active vibration absorber assembly

• US 6,009,985 A
• Filed: 02/10/1997
• Issued: 01/04/2000
• Est. Priority Date: 02/10/1997
• Status: Expired due to Fees

• Current Assignee: Lord Corporation (Parker-Hannifin Corporation)
• Original Assignee: Lord Corporation (Parker-Hannifin Corporation)
• Inventors: Ivers, Douglas E.
• Primary Examiner(s): Butler, Douglas C.
• Application Number:
  US08/799,065
• Time in Patent Office: 1,058 Days
• Field of Search: 188/378-380, 188/267, 267/136, 267/140.15, 267/140.16, 267/140.14, 248/550, 248/559, 248/636, 248/562, 248/638, 244/17.11-17.27, 244/54, 244/75 R, 381/71.1, 381/71.2, 381/71.11, 381/71.4, 381/73.1, 381/93, 381/83, 381/71.7, 181/206, 52/167.2, 52/1, 367/901, 416/500, 416/144, 180/300, 180/312, 180/902
• US Class Current: 188/380
• CPC Class Codes: F16F 2224/0283 piezoelectric; electro- or magnetostrictive
• CPC Class Codes: F16F 7/1005 characterised by active control of the mass
• CPC Class Codes: F16F 7/104 the inertia member being resiliently mounted F16F7/1022 takes precedence

Abstract

An Active Vibration Absorber assembly (20) including a casing (24), a first tuning mass (32) supported relative to the casing (24) which is actively vibratable by a force generator (40) in a first direction (along an A--A axis), a second tuning mass (32'"'"') supported relative to said casing (24) which is actively vibratable by a force generator (40'"'"') in a second direction (along axis B--B) generally orthogonal to the first direction, and a flexible member (26) flexibly supporting the casing (24). In a first embodiment, the tuning masses (32, 32'"'"') are vibratable by a magnet and coil assembly within shakers (25, 25'"'"') and the flexible member (26) is a beam. In other embodiments, multiple beams are employed to restrict the vibration of casing (24) to substantially planar motion. The AVA assembly (20) finds application in Active Structural Control (ASC) systems for actively canceling vibration or noise in vehicle cabins (example: automobiles, aircraft).

Claims

1. An active vibration absorber assembly for use with a base, said active vibration absorber comprising:

(a) a casing providing a primary tuning mass, said casing including a first housing and a second housing,

(b) a first tuning mass flexibly supported relative to said first housing,

(c) a first active force generator which is actively vibratable to vibrate said first tuning mass in a first direction,

(d) a second tuning mass flexibly supported relative to said second housing,

(e) a second active force generator which is actively vibratable to vibrate said second tuning mass in a second direction which is generally orthogonal to said first direction, and

(f) a flexible member adapted to flexibly suspend said casing from the base such that vibration of said casing is constrained substantially solely by said flexible member,

(g) wherein said first and second housings are rigidly connected.

2. An active vibration absorber assembly of claim 1 wherein said flexible member comprises at least one flexible beam.

3. An active vibration absorber assembly of claim 2 wherein said at least one flexible beam comprises a plurality of flexible beams.

4. An active vibration absorber assembly of claim 3 wherein said plurality of flexible beams comprises four or more flexible beams.

5. An active vibration absorber assembly of claim 3 wherein said plurality of flexible beams are spaced apart, such that the vibration of said casing comprises substantially planar motion.

6. An active vibration absorber assembly of claim 1 wherein said flexible member comprises an elastomer section.

7. An active vibration absorber assembly of claim 6 wherein said elastomer further comprises a planar elastomer section.

8. An active vibration absorber assembly of claim 1 wherein said assembly is included within an active structural control system, further comprising:

a) a reference sensor for providing a reference signal representative of a disturbance,

b) an error sensor for providing an error signal representative of residual, and

c) a controller for processing said reference signal and said error signal and providing drive signals to drive said first and second tuning masses within said active vibration absorber assembly.

9. An active vibration absorber assembly of claim 8 wherein said active vibration absorber assembly is adapted to be included within a vehicle.

10. An active vibration absorber assembly of claim 8 wherein said active vibration absorber assembly is adapted to be included within an aircraft.

11. An active vibration absorber assembly of claim 8 wherein said active vibration absorber assembly is adapted to be attached to a yoke assembly of an aircraft.

12. An active vibration absorber assembly of claim 1 wherein at least one of said first tuning mass and said second tuning mass is actively driven by one selected from a group consisting of:

a coil and magnet assembly, a magnetostrictive actuator, and a piezoelectric actuator.

13. An active vibration absorber assembly for use with a base, said active vibration absorber comprising:

(a) a casing providing a primary tuning mass, said casing including a first housing and a second housing,

(b) a first magnet tuning mass flexibly supported relative to said first housing by a first spring member said first magnet tuning mass being actively vibratable relative to said casing in a first direction by energizing at least one coil located adjacent to said first magnet tuning mass,

(c) a second magnet tuning mass flexibly supported relative to said second housing by a second spring member, said second magnet tuning mass being actively vibratable relative to said casing in a second direction substantially orthogonal to said first direction by energizing at least one coil located adjacent to said second magnet tuning mass, and

(d) a flexible member adapted to flexibly suspend said casing from the base such that vibration of said casing is constrained substantially solely by said flexible member,

(e) wherein said first and second housings are rigidly connected.

14. An active vibration absorber assembly for use with a base, said active vibration absorber comprising:

(a) a first inertial shaker having a first housing and a first vibratable tuning mass having a first predominant axis of vibration,

(b) a second inertial shaker having a second housing rigidly secured relative to said first housing and a second vibratable tuning mass having a second predominant axis of vibration which is oriented orthogonally relative to said first predominant axis, and

(c) a flexible member adapted to flexibly suspend said first and second housings from the base such that vibration of said casing constrained substantially solely by said flexible member.