Patent Number: 042812526
Section: summary

THE PRIOR ART As is shown in FIG. 1 of the accompanying drawings, systems for the handling of radioactive material 1 involve the provision of a storage unit 2 having a mass 3 of radiation-shielding material with a passage 4 through it, in which the radioactive material can be safely stored when not in use, as is shown in FIG. 1 at A, and from which the radioactive material can be moved to a use location, as for making a radiograph, as is shown in FIG. 1 at C. Typically, the radioactive material 1 is connected to drive means comprising a flexible cable 5 in a guide tube 6. The guide tube is generally provided in three essentially equal-lengths 6A, 6B and 6C, each of which can be disconnectibly coupled to the storage unit 2. Under control of a reel and crank arrangement 7 the drive cable 5 pushes the radioactive material out of the passage 4 and through the third guide tube 6C to a snout 8 located where the radiograph is to be made, as shown in FIG. 1 at B and C. The portion of drive cable 5 in the second guide tube 6B supplies the cable necessary to fill the first and third guide tubes 6A and 6C when a radiograph is being made. A disconnectible coupler 9 is fitted in the drive cable 5 so that when the radioactive material 1 is in the stored position the drive cable can be parted outside the storage unit for uncoupling the cable 5 and the guide tubes 6A and 6B from the storage unit. The part of drive cable 5 between the coupler 9 and the radioactive material 1 is known as the leader 11, and the coupling apparatus 10 between the guide tubes 6A and 6B and the storage unit 2 generally contains means to lock the leader against movement through the passage 4 when the drive means are uncoupled and removed. U.S. Pat. No. 3,147,383 and No. 3,593,594 describe prior systems in which these features are found. The present invention provides improved coupling apparatus, such as couplers 10 in such systems, to provide a simpler and less costly coupling apparatus without sacrificing reliability or safety. GENERAL NATURE OF THE INVENTION In the present invention coupling apparatus is provided for the first guide tube 6A, to the end of which a tubular shaped separable coupler component is fitted, and another coupler component fixed to the storage unit at one end of the passage 4 has a tubular aperture for receiving the separable component endwise, and means for releasably locking the separable component in the tubular aperture. The coupler components are aligned with the passage 4 so that the separable component will guide the drive cable 5 to the passage 4 when locked in the tubular aperture of the fixed component, which incorporates interlocking members for locking and releasing the leader 11, and the separable component, as desired. A latch pin in the fixed component retains the leader 11 locked by these interlocking members until the latch pin is released by insertion of the separable component in the tubular aperture. The interlocking members are then operable to release the leader 11 for movement through the passage 4 and to lock the separable component to the fixed component. The design of the separable component is such that the drive cable coupler 9 must be safely engaged in order for the separable component to be fitted into the tubular aperture on the fixed component and release the latch therein. When the interlocking members are operated to release the leader 11 they lock the separable component to the fixed component thereby preventing decoupling of the separable component until the leader is returned to its locked position and locked in that position, thereby safely storing the radioactive material 1 in the storage unit 2. In one embodiment of the invention, the interlocking members are slides held in respective slideways in the fixed component and arranged for movement transverse to the passage 4. In another embodiment, a single slide operable by a rotatable cam ring is arranged for such transverse movement.