Joint axis for coordinate measurement machine

• US 7,624,510 B2
• Filed: 12/21/2007
• Issued: 12/01/2009
• Est. Priority Date: 12/22/2006
• Status: Active Grant

• Current Assignee: Hexagon Metrology Incorporated (Hexagon AB)
• Original Assignee: Hexagon Metrology Incorporated (Hexagon AB)
• Inventors: Ferrari, Paul
• Primary Examiner(s): SMITH, RICHARD A
• Application Number:
  US11/963,531
• Publication Number:
  US 20090013548A1
• Time in Patent Office: 711 Days
• Field of Search: 335/03, 335/04, 335/56, 335/57, 335/59, 335/60, 356/614, 702/150, 702/152
• US Class Current: 33/503
• CPC Class Codes: G01B 21/04 by measuring coordinates of points

Abstract

One aspect of the present invention comprises a coordinate measurement apparatus that includes an articulated arm having a first end, a second end, and plurality of jointed arm segments therebetween, each arm segment including at least one position transducer. A measurement probe assembly is coupled to the second end of the arm. The measurement probe assembly comprises a first joint providing a first axis of rotation between the second end of the arm and a body of the measurement probe assembly. An encoder includes an encoder housing and an encoder shaft. The encoder housing is configured to rotate about a second axis with respect to the encoder shaft, which is rigidly coupled to the body. A probe is rigidly coupled to the encoder shaft. A measurement device is coupled to the encoder housing such that the measurement device rotates about a second axis with respect to the probe.

Claims

1. A coordinate measurement device comprising:

an articulated arm having a first end, a second end, and a plurality of jointed arm segments therebetween, each arm segment including at least one position transducer; and

a measurement probe assembly coupled to the second end of the arm, the measurement probe assembly comprising;

a first joint providing a first axis of rotation between the second end of the arm and a body of the measurement probe assembly;

a read head and an encoder disk, the encoder disk configured to rotate about a second axis with respect to the read head;

a first probe rotatably fixed with respect to the body about the second axis of rotation; and

a second probe coupled to the body such that the second probe rotates about the second axis with respect to the first probe.

2. The coordinate measurement device of claim 1 wherein said arm includes 7 axes of rotation and the first and second axes comprise the 6^th and 7^th axis of rotation respectively.

3. The coordinate measurement device of claim 2, wherein the jointed arm segments are arranged in a 2-2-3 joint configuration.

4. The coordinate measurement device of claim 1, wherein the measurement second probe is a laser scanner.

5. The coordinate measurement device of claim 1, wherein the first probe is a touch probe.

6. The coordinate measurement device of claim 1, wherein the first probe is a rigid probe.

7. The coordinate measurement device of claim 1, further comprising a slip ring provided between the read head and the second probe.

8. The coordinate measurement device of claim 1, further comprising a handle coupled to the body.

9. The coordinate measurement device of claim 1, wherein the measurement probe assembly is removably coupled to the articulated arm.

10. A coordinate measurement apparatus comprising:

an articulated arm having a first end, a second end, and plurality of jointed arm segments therebetween, each arm segment including at least one position transducer; and

a measurement assembly coupled to the second end of the arm, the measurement assembly comprising;

a first joint providing a first axis of rotation between the second end of the arm and a body of the measurement assembly;

a probe rigidly coupled to the first joint; and

a measurement device configured for rotation about the probe.

11. A portable coordinate measurement machine (CMM) for measuring the position of an object in a selected volume, comprising:

a manually positionable articulated arm having opposed first and second ends, said arm including a plurality of rotary joints; and

a measurement assembly coupled to the second end of the arm, the measurement assembly comprising a first rotable joint providing a first axis of rotation, a probe rigidly coupled to the first joint, a measurement device configured for rotation about the probe and means for rotating the measurement device about the probe along a second axis of rotation.

12. The CMM of claim 11 wherein said arm includes 7 axes of rotation and the first and second axes comprise the 6^th and 7^th axis of rotation respectively.

13. The CMM of claim 12, wherein the arm is arranged in a 2-2-3 joint configuration.

14. The CMM of claim 11, wherein the measurement device is a laser scanner.

15. The CMM of claim 11, wherein the probe is a touch probe.

16. The CMM of claim 11, wherein the probe is a rigid probe.

17. The CMM of claim 11, further comprising a handle coupled to the measurement device.

18. The CMM of claim 11, further comprising a slip ring.

19. A joint for a coordinate measurement apparatus comprising:

a joint body connectable to a coordinate measurement apparatus;

a rotatable joint defining an axis of rotation of the joint;

a first probe connector rotationally fixed with respect to the joint body about the axis of rotation of the joint; and

a second probe connector rotatable with respect to the joint body about the axis of rotation of the joint.

20. The joint of claim 19, further comprising a first probe coupled to the first probe connector.

21. The joint of claim 20, wherein the first probe comprises one of a rigid probe, an electrical contact probe, a touch trigger probe, a strain sensing probe, a laser point probe, a laser line probe, and an optical probe.

22. The joint of claim 19, further comprising a second probe coupled to the second probe connector.

23. The joint of claim 22, wherein the second probe comprises one of a rigid probe, an electrical contact probe, a touch trigger probe, a strain sensing probe, a laser point probe, a laser line probe, and an optical probe.

24. The joint of claim 19, wherein the joint is configured to be removably couplable to the coordinate measurement apparatus.