ROBOT DRIVE WITH MAGNETIC SPINDLE BEARINGS

• US 20090243413A1
• Filed: 06/27/2008
• Published: 10/01/2009
• Est. Priority Date: 06/27/2007
• Status: Active Grant

• Current Assignee: Brooks Automation Ltd. (United Kingdom) (Azenta, Inc.)
• Original Assignee: Brooks Automation Incorporated (Azenta, Inc.)
• Inventors: Hofmeister, Christopher, Hosek, Martin, Gilchrist, Ulysses, Krishnasamy, Jay, Moura, Jairo Terra
• Granted Patent: US 8,283,813 B2
• Time in Patent Office: Days
• US Class Current: 310/90.500
• CPC Class Codes: H02K 29/03 with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems
• CPC Class Codes: H02K 7/09 with magnetic bearings
• CPC Class Codes: Y10S 901/15 Jointed arm
• CPC Class Codes: Y10S 901/23 Electric motor
• CPC Class Codes: Y10T 74/20305 Robotic arm
• CPC Class Codes: Y10T 74/20317 including electric motor
• CPC Class Codes: Y10T 74/20329 Joint between elements

Abstract

A drive section for a substrate transport arm including a frame, at least one stator mounted within the frame, the stator including a first motor section and at least one stator bearing section and a coaxial spindle magnetically supported substantially without contact by the at least one stator bearing section, where each drive shaft of the coaxial spindle includes a rotor, the rotor including a second motor section and at least one rotor bearing section configured to interface with the at least one stator bearing section, wherein the first motor section is configured to interface with the second motor section to effect rotation of the spindle about a predetermined axis and the at least one stator bearing section is configured to effect at least leveling of a substrate transport arm end effector connected to the coaxial spindle through an interaction with the at least one rotor bearing section.

Claims

1. A drive section for a substrate transport arm comprising:

a frame;

at least one stator mounted within the frame, the stator including a first motor section and at least one stator bearing section; and

a coaxial spindle magnetically supported substantially without contact by the at least one stator bearing section, where each drive shaft of the coaxial spindle includes a rotor, the rotor including a second motor section and at least one rotor bearing section configured to interface with the at least one stator bearing section;

wherein the first motor section is configured to interface with the second motor section to effect rotation of the spindle about a predetermined axis and the at least one stator bearing section is configured to effect at least leveling of a substrate transport arm end effector connected to the coaxial spindle through an interaction with the at least one rotor bearing section.

2. The drive section of claim 1, wherein the at least one stator bearing section is configured to interface with the at least one rotor bearing section to change at least an angular orientation of the predetermined axis of rotation with respect to a centerline of the at least one stator.

3. The drive section of claim 1, wherein the frame is located within a housing, the drive section being coupled to the frame and configured to linearly translate the frame within the housing.

4. The drive section of claim 1, wherein the at least one stator and rotor are isolated from one another where the at least one stator operates in a first environment and the rotor operates in a second environment.

5. The drive section of claim 1, further comprising a drive section feedback system comprising at least one sensor configured to measure a planar position of the predetermined axis of rotation and an angular orientation of the predetermined axis of rotation.

6. The drive section of claim 1, wherein the coaxial spindle comprises at least two drive shafts each having a rotor and the at least one stator comprises at least two stators where each of the at least two stators is configured to interface with a respective one of the rotors and cause a change in angular orientation of the predetermined axis of rotation.

7. The drive section of claim 1, wherein the at least one stator bearing section is configured to interface with the rotor bearing section and axially offset a centerline of the coaxial spindle from a centerline of the at least one stator.

8. The drive section of claim 7, wherein axially offsetting the centerline of the coaxial spindle effects planar positional adjustment of the end effector.

9. The drive section of claim 1, wherein the at least one stator comprises two stators and the coaxial spindle comprises two drive shafts each having a respective rotor, where the two stators and the respective rotors provide six degrees of freedom for the drive section.

10. The drive section of claim 1, wherein the at least one stator comprises two stators and the coaxial spindle comprises two drive shafts each having a respective rotor, where the two stators and the respective rotors provide seven degrees of freedom for the drive unit.