SHAPE MEASURING APPARATUS

• US 20110066400A1
• Filed: 09/09/2010
• Published: 03/17/2011
• Est. Priority Date: 09/15/2009
• Status: Active Grant

• Current Assignee: Mitutoyo Corporation
• Original Assignee: Mitutoyo Corporation
• Inventors: NODA, Takashi, UEDA, Kenji
• Granted Patent: US 8,478,564 B2
• Time in Patent Office: Days
• US Class Current: 702/168
• CPC Class Codes: G01B 5/008 using coordinate measuring machines

Abstract

A 3D measuring apparatus includes a probe that has a spherical gauge head for measuring a measured object; a motion mechanism that holds and moves the probe; and a motion controller that controls the motion mechanism. The controller includes a contact point obtainer that obtains a contact point location of a surface of the measured object and the gauge head based on a central location of the gauge head; a radius of the gauge head; and a swing amount of the gauge head. The controller also includes a motion commander that calculates a location command value causing the motion mechanism to move the probe, based on the contact point location obtained by the contact point obtainer.

Claims

1. A shape measuring apparatus comprising:

a probe having a gauge head configured to contact a measured object, the probe configured to move the gauge head within a predetermined area;

a mover configured to move the probe; and

a controller configured to control the mover, wherein;

a shape of the measured object is measured by moving the gauge head along a surface of the measured object while the gauge head is pressed against the measured object, and

the controller comprises;

a contact point obtainer configured to obtain a contact point location of the surface of the measured object and the gauge head; and

a motion commander configured to calculate, based on the contact point location, a location command value causing the mover to move the probe.

2. The shape measuring apparatus according to claim 1, wherein the gauge head has a spherical shape, and the contact point obtainer calculates and obtains the contact point location based on:

a central location of the gauge head;

a radius of the gauge head; and

a normal direction of the contact point.

3. The shape measuring apparatus according to claim 2, wherein the contact point obtainer calculates the normal direction of the contact point based on a swing amount of the gauge head.

4. The shape measuring apparatus according to claim 1, wherein the controller comprises a measured value calculator that calculates a measured value based on a movement amount of the motion mechanism and the contact point location.

5. The shape measuring apparatus according to claim 2, wherein the controller comprises a measured value calculator that calculates a measured value based on a movement amount of the motion mechanism and the contact point location.

6. The shape measuring apparatus according to claim 3, wherein the controller comprises a measured value calculator that calculates a measured value based on a movement amount of the motion mechanism and the contact point location.