Patent ID: 6182932
Filing Date: 2001-02-06
Classification: F22B

Abstract:
An apparatus for supporting and positioning tools for inspecting a nuclear power plant steam generator, comprising:a housing;at least one lock assembly carried by the housing for coupling the housing to a support structure; anda carriage assembly supported by the housing for supporting and positioning inspection tools;the lock assembly includinga tubular member defining an open center and at least two openings in the surface of the tubular member;a shaft received in the open center, the shaft defining at least two recessed surfaces, each recessed surface supporting at least one ball sized to be received in the openings defined by the tubular member, wherein a portion of each ball contacts a portion of the shaft and an adjacent external surface when received in the openings; anda cylinder supporting a movable piston coupled to the shaft for moving the shaft relative to the tubular member so as to cause the balls to be moved off each recessed surface and to be received in the opening defined by the tubular member, the cylinder being coupled to an energy source,whereby the lock couples the housing to the external surface when the balls are forced off the recessed surfaces and into the openings defined by the tubular member, wherein each ball is wedged between the shaft and the external surface.