| 摘要 |
932,240. Controlling reactors. GENERAL DYNAMICS CORPORATION. July 20, 1960 [July 28, 1959], No. 25362/60. Class 39 (4). A control rod drive includes a reversible electric motor with a biasing arrangement to prevent the rod from drifting out of position under the influence of a steady force such as gravity. Fig. 5 shows a control circuit for a two-phase motor 38. Opening switches 43, 49 moves the control rod up and down respectively. An adjustable biasing resistance 45 causes a small phase difference between the coils of the motor, producing a slight torque tending to raise the control rod. The right-hand part of Fig. 5 shows an arrangement of microswitches for limiting the travel of the rod. Fig. 1 shows part of the mechanism, including an electromagnetic coupling at 21, 22 and orifices of differing sizes at 15, 16, 17. One face of the coupling is curved to prevent sticking due to residual magnetism, and the orifices provide increasing braking, by throttling the outflow of liquid moderator, as the control rod falls. A potentiometer is provided as a position indicator. U.S.A. Specification 2,779,728 is referred to. |
