Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
  • G01B5/00—Measuring arrangements characterised by the use of mechanical techniques
  • G01B5/004—Measuring arrangements characterised by the use of mechanical techniques for measuring coordinates of points
  • G01B5/008—Measuring arrangements characterised by the use of mechanical techniques for measuring coordinates of points using coordinate measuring machines
  • G01B5/012—Contact-making feeler heads therefor
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
  • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
  • G01B7/004—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring coordinates of points
  • G01B7/008—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring coordinates of points using coordinate measuring machines
  • G01B7/012—Contact-making feeler heads therefor

Definitions

• a position deterniining apparatus may be used for measuring a workpiece, and typically comprises an arm moveable in three directions x,y,z relative to a table on which the workpiece is supported. Movement of the arm in each of the directions x,y,z is measured b transducers on the machine, and a probe assembly provided on the arm produces a signal indicating the relationship between the workpiece surface to be measured, and the arm. The position of the surface of the workpiece may thus be determined.
• the table moves in x and y and the arm moves in z.
• a first aspect of the present invention describes a motor.
• the motor may be a frameless motor.
• a first motor for actuating rotation of the first member relative to the body about the first axis of rotation, the first motor comprising a frameless motor;
• the first motor is arranged such that when it actuates rotation of the first member relative to the body, substantially no radial forces act on the first bearings such that the location of the first axis remains substantially fixed.
• the position of the first axis of rotation can be more accurately known. Due to the lack of radial pull on the bearing problems of run-out and swash which are commonly encountered are reduced, or even avoided. This can allow the metrology apparatus to accurately determine the position of an object without the need for extremely stiff bearings or extensive error mapping.
• the first motor is arranged such that when it actuates rotation of the first member relative to the body, substantially no axial forces act on the first bearings. The lack of axial forces may enable a less stiff bearing to be used.
• a frameless motor may be a motor without its own set of bearings.
• a frameless motor may rotate using the bearings of the axis to which it is fitted.
• the ironless-core motor may provide movement of a device supported by the metrology apparatus relative to the coordinate positioning apparatus. Said movement may be, in particular, rotational movement about one or more axes. Where the metrology apparatus is a coordinate positioning apparatus, the ironless-core motor may provide movement of a device supported by the metrology apparatus relative to a fixed surface.
• a fourth aspect of the present invention provides a metrology apparatus comprising:
• first member rotatable relative to the body about a first axis of rotation, said first axis being defined by first bearings;
• the first motor comprises a frameless ironless core motor.
• the metrology apparatus may comprise an attachment means for attaching a body to the moveable arm of a machine.
• the body may be a support.
• first member rotatable relative to the body about a first axis of rotation, said first axis being defined by first bearings;

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)
• Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
• A Measuring Device Byusing Mechanical Method (AREA)

Priority Applications (5)

Applications Claiming Priority (6)

Publications (1)

Family

ID=44546336

Family Applications (1)

Country Status (6)

Families Citing this family (23)

Citations (7)

Family Cites Families (10)

• 2011
  • 2011-04-28 JP JP2013506733A patent/JP2013540981A/ja active Pending
  • 2011-04-28 CN CN201180020880.3A patent/CN102859316B/zh active Active
  • 2011-04-28 BR BR112012027939A patent/BR112012027939A2/pt not_active IP Right Cessation
  • 2011-04-28 EP EP11724276.8A patent/EP2564152B1/en active Active
  • 2011-04-28 WO PCT/GB2011/000652 patent/WO2011135298A1/en not_active Ceased
  • 2011-04-28 US US13/638,429 patent/US9377284B2/en active Active

Patent Citations (7)

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