Systems and methods of providing improved performance of scanning mirrors coupled to limited rotation motors

• US 8,284,470 B2
• Filed: 04/21/2010
• Issued: 10/09/2012
• Est. Priority Date: 04/23/2009
• Status: Active Grant

• Current Assignee: Novanta Corporation (Novanta Inc.)
• Original Assignee: Cambridge Technology Development Incorporated (Novanta Inc.)
• Inventors: Brown, David C., Pinard, Adam I.
• Primary Examiner(s): Doak, Jennifer L.
• Application Number:
  US12/764,392
• Publication Number:
  US 20100271679A1
• Time in Patent Office: 902 Days
• Field of Search: 3591961-2263, 359227-236, 359831-884, 248/648, 248/123.11, 248/162.1, 248/280.11, 248/334.1, 248/364, 49/99, 491/19, 491/50
• US Class Current: 359/198.1
• CPC Class Codes: F16F 15/023 using fluid means
• CPC Class Codes: F16F 2222/04 Friction
• CPC Class Codes: F16F 2222/08 Inertia
• CPC Class Codes: F16F 7/00 Vibration-dampers; Shock-absorbers using fluid F16F5/00, F16F9/00; specific for rotary systems F16F15/10 ; belt tensioners F16H7/12
• CPC Class Codes: F16F 7/01 using friction between loose particles, e.g. sand
• CPC Class Codes: G02B 26/105 with one or more pivoting mirrors or galvano-mirrors G02B26/101 takes precedence
• CPC Class Codes: G02B 7/1821 for rotating or oscillating mirrors

Abstract

A mirror is disclosed for use in a limited rotation motor system, wherein the mirror includes a body, an aperture within the body, and a high density material within the aperture. The body, formed of one or more materials, has an exposed mirror surface and is mountable with the limited rotation motor system for rotation with respect to an axis of mirror rotation. The aperture is positioned at least proximate to a portion of the axis of mirror rotation. The high density material is provided within the aperture such that it is capable of movement within the aperture, and the high density material has a density that is greater than a density of the material of the body of the mirror.

Claims

1. A mirror for use in a limited rotation motor system, said mirror comprising:

a body formed of at least one material and having an exposed mirror surface, said body being mountable with the limited rotation motor system for rotation with respect to an axis of mirror rotation;

an aperture within the body of the mirror, said aperture being at least proximate to a portion of said axis of mirror rotation; and

a high density material within said aperture and capable of movement within said aperture with respect to the body of the mirror, said high density material having a density that is greater than a density of the at least one material of the body of the mirror.

2. The mirror as claimed in claim 1, wherein said high density material is provided as particles of a solid material.

3. The mirror as claimed in claim 2, wherein said particles are provided within an elastomeric material within said aperture.

4. The mirror as claimed in claim 2, wherein said particles each have a size between about 1 micron and about 5 microns.

5. The mirror as claimed in claim 2, wherein said high density material is formed of any of tungsten, depleted uranium, molybdenum, lead and bismuth.

6. The mirror as claimed in claim 1, wherein said high density material is provided as a fluid.

7. The mirror as claimed in claim 1, wherein said fluid is mercury.

8. The mirror as claimed in claim 1, wherein said aperture is substantially coincident with at least a portion of the axis of mirror rotation.

9. A scanning system including a limited rotation motor coupled to a mirror, said limited rotation motor comprising a rotor shaft and said mirror comprising:

a body having an exposed mirror surface and being coupled to the rotor shaft of the limited rotation motor system for rotation with respect to an axis of mirror rotation;

a high density material within an aperture in the body of the mirror, said high density material being capable of movement within said aperture with respect to the body of the mirror, and said high density material having a density that is greater than a density of the body of the mirror.

10. The scanning system as claimed in claim 9, wherein said high density material is provided as particles of a solid material.

11. The scanning system as claimed in claim 10, wherein said particles are provided within an elastomeric material within said aperture.

12. The scanning system as claimed in claim 10, wherein said particles each have a size between about 1 micron and about 5 microns.

13. The scanning system as claimed in claim 10, wherein said high density material is formed of any of tungsten, depleted uranium, molybdenum, lead and bismuth.

14. The scanning system as claimed in claim 9, wherein said high density material is provided as a fluid.

15. The scanning system as claimed in claim 9, wherein said fluid is mercury.

16. The scanning system as claimed in claim 9, wherein said aperture is substantially coincident with at least a portion of the axis of mirror rotation.

17. A method of damping vibrations in a scanning system that includes a limited rotation motor including a rotor shaft, and a mirror coupled to the rotor shaft of the limited rotation motor, said method comprising the steps of:

rotating the mirror about an axis of mirror rotation through application of a torque applied to the mirror by the limited rotation motor via the rotor shaft; and

accelerating a high density material within the mirror due to vibrations in the movement of the minor, whereby the acceleration of the high density material within the mirror absorbs energy from the vibrations thereby damping vibrations in the scanning system.

18. The method as claimed in claim 17, wherein said high density material is provided as particles of a solid material.

19. The method as claimed in claim 18, wherein said particles each have a size between about 1 micron and about 5 microns.

20. The method as claimed in claim 17, wherein said high density material is formed of any of tungsten, depleted uranium, molybdenum, lead and bismuth.