Method and apparatus for rotating a flaw detector about a test piece and guiding it relative to undulations and bends

Claim 1

Apparatus for nondestructively inspecting elongated workpieces having relatively small diametrical extents and moving along a path of travel comprising: a. a support unit disposed about said path of travel; b. structure supporting said support unit for rotation about a first axis generally coextending with said path of travel; c. drive means for rotating said support unit about said first axis; d. an inspection head carried by said support unit for rotation therewith; and, e. a head support member coupled between said head and said support unit for enabling movement of said head relative to said support unit toward and away from said first axis; f. said head comprising: i. a supporting element; ii. structure for connecting said supporting element to said head support member for relative universal movement; iii. a guide structure coupled to said supporting element for pivotal movement relative to a second axis extending generally parallel to said first axis and comprising a support housing and divergent workpiece engaging surfaces which project from said housing and engage said workpiece to track along undulations in the workpiece by pivoting about said second axis as said surfaces move about the workpiece; iv. a sensor assembly supported at least partly within said support housing for pivotal movement with said guide structure about said second axis and including a portion projecting from said support housing toward said first axis; v. bearing elements connecting said sensor assembly to said support housing for pivotal movement relative to said guide structure about a third axis extending generally transverse to said second axis and for translational movement relative to said support housing toward and away from said first axis; and, vi. means for biasing said sensor assembly toward engagement with a workpiece engaged by said workpiece engaging surfaces, said means for biasing said sensor assembly cooperating with said bearing elements to maintain said sensor assembly in engagement with workpiece undulations disposed generally in a plane extending through said first and second axes relative to the sensor assembly.

Claim 7

A method of detecting flaws in elongated workpieces having relatively small diametrical extents traveling along a path comprising: a. stationing a rotatable support unit about the path; b. coupling an inspection head to the support unit, the inspection head including a supporting element, guide structure connected to the supporting element and a sensor assembly connected to the guide structure; c. rotating the support unit and inspection head about a first axis generally coextending with said path; d. moving said inspection head toward said path relative to said support unit; e. engaging said guide structure with a workpiece on said path at least at first and second locations spaced apart peripherally along the workpiece. f. resiliently engaging said sensor assembly with the workpiece at a third location adjacent said first and second locations; and, g. maintaining said sensor assembly in contact with undulations in the workpiece moving along the path as the support unit moves about the workpiece by: i. universally moving said head relative to the support unit in response to the guide structure encountering workpiece undulations so that the sensor assembly tends to maintain contact with the workpiece; ii. pivoting said guide structure and said sensor assembly as a unit relative to said supporting element about a second axis extending generally parallel to said first axis in response to the guide structure encountering workpiece undulations; iii. pivoting said sensor assembly relative to said guide structure about a third axis extending in a direction generally transverse to said first and second axes in response to the sensor assembly encountering workpiece undulations; iv. resiliently shifting said sensor assembly toward and away from said path realtive to said guide structure while maintaining said sensor assembly engaged with the workpiece.

Claim 8

A method of detecting flaws in elongated workpieces having relatively small diametrical extents traveling along a path comprising: a. stationing a rotatable support unit about the path; b. coupling an inspection head to the support unit, the inspection head including a supporting element, guide structure connected to the supporting element and a sensor assembly connected to the guide structure; c. rotating the support unit and inspection head about a first axis generally coextending with said path; d. moving said inspection head toward said path relative to said support unit; e. engaging said guide structure with a workpiece on said path at least at first and second locations spaced apart peripherally along the workpiece. f. resiliently engaging said sensor assembly with the workpiece at a third location adjacent said first and second locations; and, g. maintaining said sensor assembly in contact with undulations in the workpiece moving along the path as the support unit moves about the workpiece by: i. universally moving said head relative to the support unit in response to the guide structure encountering workpiece undulations so that the sensor assembly tends to maintain contact with the workpiece; ii. pivoting said guide structure and said sensor assembly as a unit relative to said supporting element about a second axis extending generally parallel to said first axis in response to the guide structure encountering workpiece undulations; iii. pivoting said sensor assembly relative to said guide structure about a third axis extending in a direction generally transverse to said first and second axes in response to the sensor assembly encountering workpiece undulations; iv. resiliently shifting said sensor assembly toward and away from said path realtive to said guide structure while maintaining said sensor assembly engaged with the workpiece.