Patent GB-984507-A (GB)
Title: A system for remotely positioning a movable member
Inventor: AUBERT MICHEL
IPC: G21C19/18
Filed: 1963-09-09
Abstract: 984, 507. Fuelling reactors. COMMISSARIAT A L'ENERGIE ATOMIQUE. Sept. 9, 1963 [Sept. 26, 1962], No. 35549/63. Heading G6C. In a fuelling arrangement as disclosed in Specifications 953, 297 and 953, 298 in which a radial. beam 22 supporting a fuel handling unit 44 is rotated by a motor around a circular space 18 above the reactor core, the unit 44 being movable by a further motor along the beam, optical means are provided which view index marks in the space 18. These marks are located at the various angular positions to which the beam 22 must be rotated and at the various positions on the beam to which the unit 44 must be moved in order to align the unit with the selected charge hole 21 extending through a cap 20 above the core. The optical means transmit the index marks and these images are converted to electric signals for transmission to a remote location. These signals are applied to a comparator also receiving signals from a preset memory. The memory signal relates to the selected charge hole and when this signal agrees with the signals transmitted by the optical means the comparator produces an output which is applied to the motors driving the beam 22 and unit 44 so that these motors are stopped and the unit is arrested in alignment with the selected hole. The optical means comprises a periscope arrangement including a mirror 90 rotatable with the beam 22, the image being applied to a television camera 92 mounted above the top of the reactor shield. The image from the camera is transmitted to a television receiver 94 where it may be viewed, the output from the receiver being connected to a comparator 106 also receiving an input from a memory unit 104. The mirror 90 is movable vertically between the two positions shown. In the upper position the mirror sees a short segment of an annular zone 96 around the wall of space 18, whilst in its lower position it sees the image formed by another mirror 98 mounted on the unit 44. Index marks are spaced at intervals around the zone 96 corresponding with the radii along which the holes 21 are located, these marks being provided by light and dark areas in binary code form, three such marks being shown to the right of reference 96 in Fig. 3. The mirror 98 scans a radial strip of the cap 20 as the unit 44 moves along the beam and each hole 21 has an index mark in the form of a binary code (Fig. 4, not shown). The mirror 98 also views index marks provided on a motor driven turntable 50 so that a grab 52 on the turntable may be aligned with a desired compartment of the fuel element magazine 46 carried by the unit 44 as disclosed in the aforementioned Specifications. Three signals may be stored in the memory 104, one signal relating to the desired radial position of the beam, another signal relating to the desired position of the unit 44 on the beam and a further signal relating to the selected compartment of the magazine 46. The signals produced by the index marks and supplied to the comparator 106 from the T.V. receiver 94 produce sequentially three outputs, F 2 , F¢ F¢<SP>1</SP> when they are coincident with the signals stored in the memory and respectively stop the three motors driving the beam 22, unit 44 and turntable 50. The alignment of the beam 22 with the rail 67 leading to the exterior of the reactor is observed by a further optical system 69 providing an image to a further T.V. camera 70, this camera supplying a T.V. receiver 72 connected to a comparator 102 also supplied by a memory 100. The comparator supplies a signal F 1  to arrest the beam 22 when it is in alignment with the rail 67. General viewing is provided by an optical system 74, a T.V. camera 76 and T.V. receiver 78 and a number of such arrangements may be spaced around the reactor to supervise the space 18.