Handling of radio-active sources

Claim 3

Manipulating apparatus for withdrawing and inserting a radio-active source holder from and to a hole in a shielded transport container for the source holder and for transferring the source holder to and from a location beyond the container, comprising a curved tube adapted to receive The source holder and mounted for rotation about the central axis of one of its ends so that the other end can be selectively brought into alignment with the hole in the container or with at least one guide path for the source holder externally of the container, and an operating mechanism for effecting rotation of the curved tube only in response to movement of the source holder through the operating mechanism under the influence of a remotely-driven control cable attached to the source holder.

Claim 4

Manipulating apparatus for withdrawing and inserting a radio-active source holder from and to a hole in a shielded transport container for the source holder and for transferring the source holder to and from a location beyond the container, comprising a curved tube adapted to receive The source holder and mounted for rotation about the central axis of one of its ends so that the other end can be selectively brought into alignment with the hole in the container or with at least one guide path for the source holder externally of the container, and an operating mechanism for effecting rotation of the curved tube only in response to movement of the source holder through the operating mechanism under the influence of a remotely-driven control cable attached to the source holder.

Claim 5

Apparatus according to claim 2 including a mounting case securable to the transport container and carrying the operating mechanism, the mounting case including a fixed tube constituting said external guide path and a socket for receiving a safety screw of the container when the screw is in a position at which it permits withdrawal of the source holder from the hole in the container.

Claim 6

Apparatus according to claim 3, wherein the curved tube is provided with a slot in its side and the mounting case carries a roller which is spring-influenced to engage through the slot when the said other tube end is aligned with the hole in the container.

Claim 7

Apparatus according to claim 4, wherein the mounting case carries a key-operated pivotable plate for locking the roller in its slot-engaging position.

Claim 8

Apparatus according to claim 4, wherein the curved tube carries a cam disc which is fixed for rotation therewith and is adapted to hold the roller out of engagement with the slot unless the said other tube end is aligned with the hole in the container.

Claim 9

Apparatus according to claim 2, wherein the operating mechanism comprises a housing, a sleeve mounted for rotation in the housing, the curved tube being fixed with its said one end in the sleeve, a hollow piston which is constrained to execute limited rectilinear displacement in the housing between one end of the housing and a stop on the sleeve and is concentric with and surrounds the sleeve, an abutment on the piston, the cable being able to pass through the sleeve, abutment and housing and the source holder being able to enter the piston up to the abutment when pulled through the sleeve by the cable, a spring for biassing the piston against the stop on the sleeve, a cam track provided on the sleeve and at least one cam follower pin projecting from the piston into the cam track, the cam track comprising at least two helical portions interconnected by straight line portions extending parallel to the rotary axis of the sleeve so that the cam track is closed on itself, and the arrangement being such that, when the source holder has been pulled by the cable up to the abutment and the pull is maintained to overcome the bias of the spring, the source holder will displace the piston from its limiting position against the stop on the sleeve to its limiting position against the said one end of the housing, during which time the sleeve and the curved tube fixed thereto are rotated by the cam follower pin traversing one of the helical cam track portions and, when the pull is released, the spring will return the piston to its limiting position against the stop on the sleeve, during which time the cam follower pin traverses one of the straight line cam track portions without causing the sleeve to rotate.