Probe carrier drive assembly

A probe carrier drive assembly for moving a probe carrier in a tube, comprising:

• (a) a drive shaft having external threads and having a longitudinal drive slot extending through the external threads along the longitudinal axis of said drive shaft;
• (b) a first sleeve surrounding a longitudinal portion of said drive shaft;
• (c) a rotary drive shaft insert integrally attached to the inside surface of said first sleeve, said drive shaft insert outwardly projecting from the inside surface of said first sleeve for rotatably matingly engaging the drive slot of said drive shaft and for rotating said drive shaft about the longitudinal axis thereof;
• (d) a second sleeve surrounding a different longitudinal portion of said drive shaft, said second sleeve having internal threads for matingly engaging the external threads of said drive shaft and for axially translating said drive shaft along the longitudinal axis of said tube;
• (e) first rotating means operatively coupled to said first sleeve for rotating said first sleeve;
• (f) second rotating means operatively coupled to said second sleeve for rotating said second sleeve;
• and
• (g) controller means operatively coupled to said first rotating means and to said second rotating means for selectively operating said first rotating means and said second rotating means so that said drive shaft selectively axially moves in the tube and rotatably moves in the tube, whereby said drive shaft selectively rotates in place, follows a linear path or follows a helical path having a variable pitch.

A probe carrier drive assembly for moving a probe carrier in a steam generator tube, comprising:

• (a) a probe having a nondestructive examination scanning device attached thereto for nondestructively examining the tube, said probe capable of being inserted into the tube;
• (b) a hollow drive shaft connected to said probe for supporting said probe, said drive shaft having external threads thereon and having a drive slot formed through the external threads;
• (c) a first sleeve surrounding a longitudinal portion of said drive shaft;
• (d) a rotary drive shaft insert integrally attached to the inside surface of said first sleeve, said drive shaft insert outwardly projecting from the inside surface of said first sleeve for rotatably matingly engaging the drive slot of said drive shaft for rotating said drive shaft about the longitudinal axis of said drive shaft;
• (e) a second sleeve surrounding a different longitudinal portion of said drive shaft, said second sleeve having internal threads for matingly engaging the external threads of said drive shaft and for rotatably axially translating said drive shaft along the longitudinal axis of said tube, said second sleeve colinearly disposed with respect to said first sleeve;
• (f) a variable speed first reversible motor coupled to said first sleeve for rotating said first sleeve;
• (g) a variable speed second reversible motor coupled to said second sleeve for rotating said second sleeve;
• (h) a housing surrounding the drive assembly and connected thereto for enclosing said probe carrier drive assembly therein, said housing having an open front end and an open rear end for providing access to the inside of said housing and having at least two end cover plates for covering the open front end and the open rear end of said housing when the drive assembly is operating;
• (i) controller means operatively coupled to said first reversible motor and to said second reversible motor for selectively operating said first reversible motor and said second reversible motor so that said drive shaft selectively axially and rotatably moves in the steam generator tube, whereby the drive shaft selectively rotates in place, follows a linear scanning path through the steam generator tube or follows a helical scanning path having a variable pitch;
• and
• (j) support means connected to said housing, said support means capable of supporting said probe carrier drive assembly coaxially with respect to the tube.