Global to push GA events into
skip to main content

Title: Automatic ball bar for a coordinate measuring machine

An automatic ball bar for a coordinate measuring machine determines the accuracy of a coordinate measuring machine having at least one servo drive. The apparatus comprises a first and second gauge ball connected by a telescoping rigid member. The rigid member includes a switch such that inward radial movement of the second gauge ball relative to the first gauge ball causes activation of the switch. The first gauge ball is secured in a first magnetic socket assembly in order to maintain the first gauge ball at a fixed location with respect to the coordinate measuring machine. A second magnetic socket assembly secures the second gauge ball to the arm or probe holder of the coordinate measuring machine. The second gauge ball is then directed by the coordinate measuring machine to move radially inward from a point just beyond the length of the ball bar until the switch is activated. Upon switch activation, the position of the coordinate measuring machine is determined and compared to known ball bar length such that the accuracy of the coordinate measuring machine can be determined.
  1. (Naperville, IL)
Issue Date:
OSTI Identifier:
Universities Research Association, Inc. (Washington, DC) FNAL
Patent Number(s):
US 5647136
Contract Number:
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Country of Publication:
United States
automatic; ball; bar; coordinate; measuring; machine; determines; accuracy; servo; drive; apparatus; comprises; gauge; connected; telescoping; rigid; switch; inward; radial; movement; relative; causes; activation; secured; magnetic; socket; assembly; maintain; fixed; location; respect; secures; arm; probe; holder; directed; move; radially; length; activated; position; determined; compared; radial movement; ball bar; radially inward; measuring machine; coordinate measuring; apparatus comprises; switch activation; apparatus comprise; move radially; servo drive; automatic ball; /33/73/