Joint for coordinate measurement device
AssigneeHexagon Metrology, Inc.
InventorsPaul Ferrari, Dongmei Hong
Life of this patent
Estimating the term…
Abstract
An articulating joint for a coordinate measurement machine can include an improved optical encoder. The optical encoder can have an encoder hub and a read head that are rotatable with respect to each other based on movement of the articulating joint about an axis of rotation of the joint. The encoder hub has a read surface. The read surface can be an outer surface of a generally cylindrical segment. The read head can be positioned such that a read direction defined by the read surface is generally perpendicular to the axis of rotation of the articulating joint.
Claims17
A coordinate measuring machine comprising:
- a first transfer member;
- a second transfer member;
- and
- an articulating joint assembly rotatably coupling the first transfer member to the second transfer member and defining an axis of rotation, said articulating joint comprising:
- a housing;
- and
- a shaft rotatable relative to said housing;
- and
- an encoder assembly comprising:
- a read head coupled to one of said housing and said shaft;
- and
- an encoder hub attached the other of said housing and said shaft, the encoder hub having a read surface;
- wherein said encoder read head and the read surface of the encoder hub define a read direction of the encoder assembly, and wherein the read direction is transverse to the axis of rotation of the articulating joint.
A coordinate measuring machine comprising:
- a manually positionable articulated arm having opposed first and second ends, said arm including a plurality of arm segments connected together by joints, each joint rotating about a rotational axis,
- a measurement probe attached to a first end of said articulated arm;
- and
- a plurality of encoders, wherein at least one of said encoders comprises an encoder hub that rotates about the rotational axis of the joint and an encoder read head, the encoder hub including gratings that extend in a direction that is substantially parallel to the rotational axis of the articulating joint.
Dependencies are inferred from the claim text.