Coordinate measuring machine having articulated arm

A coordinate measuring machine comprising:

• a support structure;
• a first articulated arm having a first end pivotally connected to said support structure and a second end that is movable in a horizontal plane;
• a second articulated arm having a first end pivotally connected to said support structure and a second end that is movable in said horizontal plane;
• a Z-ram assembly including a Z-ram housing mounted to the second ends of said first and second articulated arms and a probe that is vertically movable with respect to said Z-ram housing, whereby said probe is movable within a measurement volume defined by said first and second articulated arms and said Z-ram assembly;
• and
• a measuring assembly for determining coordinates of said probe in said measurement volume, said measuring assembly including means for sensing a position of the Z-ram housing in said horizontal plane and means for sensing a position of said probe relative to said Z-ram housing,
• means, rigidly connected to said support structure and said Z-ram assembly and rotationally coupled to said first and second articulated arms, for preventing rotation of said Z-ram relative to said support structure, thereby maintaining said Z-ram assembly in fixed angular relationship with respect to said support structure as said Z-ram assembly moves to an arbitrary position in said horizontal plane.

A coordinate measuring machine comprising:

• a table for supporting a workpiece for coordinate measurement;
• a support structure that is fixed in position relative to said table;
• an articulated arm having a first end pivotally connected to said support structure and a second end that is movable in a horizontal plane;
• a Z-ram assembly including a Z-ram housing mounted to the second end of said articulated arm and a probe that is vertically movable with respect to said Z-ram housing, whereby said probe is movable within a measurement volume defined by said articulated arm and said Z-ram assembly;
• and
• a measuring assembly for determining coordinates of said probe in said measurement volume, said measuring assembly including means for sensing a position of the Z-ram housing in said horizontal plane and means for sensing a position of said probe relative to said Z-ram housing,
• means, rigidly connected to said support structure and said Z-ram assembly, for preventing rotation of said Z-ram relative to said support structure, thereby maintaining said Z-ram assembly in fixed angular relationship with respect to said support structure as said Z-ram assembly moves to an arbitrary position in said horizontal plane.

A coordinate measuring machine comprising:

• a support structure;
• an articulated arm having a first end pivotally connected to said support structure and a second end that is movable in a horizontal plane, including a first arm assembly pivotally connected to said support structure for movement in said horizontal plane, and a second arm assembly pivotally connected to an end of said first arm assembly for movement in said horizontal plane;
• a Z-ram assembly including a Z-ram housing mounted to the second end of said articulated arm and a probe that is vertically movable with respect to said Z-ram housing, whereby said probe is movable within a measurement volume defined by said articulated arm and said Z-ram assembly;
• and
• a measuring assembly for determining coordinates of said probe in said measurement volume, said measuring assembly including means for sensing a position of the Z-ram housing in said horizontal plane and means for sensing a position of said probe relative to said Z-ram housing;
• wherein first, second, third, fourth, fifth and sixth vertical pivot axes are associated with said first and second arm assemblies, and further wherein said first arm assembly includes a first arm member connected between a first and third pivot axes, a second arm member connected between a second and fourth pivot axes, and a first link member connected between said third and fourth pivot axes, and said second arm assembly includes a third arm member connected between said third and fifth pivot axes, a fourth arm member connected between said fourth and sixth pivot axes, and a second link member connected between said fifth and sixth pivot axes, said Z-ram assembly being connected to said second link member .