Accuracy verification devices for coordinate measuring machines

A method for verifying the accuracy of a measuring machine including a fixed element, a probe, measuring devices for measuring the position of the probe relative to the fixed element, and a processor, comprising the steps of:

• (a) positioning a block having a surface with a predetermined nonplanar contour along a direction of elongation, having predetermined characteristics with respect to the fixed element;
• (b) guiding the probe along said direction of elongation while continuously contacting said surface, coordinates measured by said measuring devices representing the movement of the probe;
• (c) processing the measuring coordinates in the processor to yield measuring characteristics of the contour;
• and
• (d) comparing the measured characteristics of said contour with the predetermined characteristics to determine an indication of the accuracy of the measuring machine.

An accuracy verification device for verifying the accuracy of a measuring machine including a fixed element, a movable element and measuring devices for measuring the position of the movable element relative to the fixed element, said device comprising;

• a block adapted to be mounted in a fixed position relative to the fixed element of the matching, said block having a linear scale mounted along a direction of elongation said block having an upper surface with an upwardly facing V-shaped channel disposed therein for guiding a probe attached to the movable member along said direction of elongation;
• a support member adapted to be attached to the movable element of the measuring machine and adapted for movement along said direction of elongation of said block with the movable element;
• and
• an encoder disposed on said support member at a position proximate said linear scale for reading the distance traveled along said linear scale when said support member moves with respect to said block,
• a movable block adapted to be disposed in said V-shaped channel, said movable block adapted to provide a contract force during a measurement procedure,
• wherein a difference between a reading of said encoder and a value derived from readings of the measuring devices being indicative of the accuracy of the machine.

An accuracy verification device for verifying the accuracy of a measuring machine including a fixed element, a movable element and measuring devices for measuring the position of the movable element relative to the fixed element, said device comprising:

• a block for mounting a fixed position relative to the fixed element of the measuring machine, said block having a guideway formed in a surface of the block, said guideway having at least two side surfaces;
• and
• a plurality of switches, disposed on said block along said guideway at known distances and adapted to signal the measuring machine when the movable element moves along said guideway,
• wherein the known distance between said plurality of switches is compared to a distance, derived from readings of the measuring devices, that the movable element has moved between said plurality of switches to determine the accuracy of the measurement machine.