| 摘要 |
<p>822,167. Automatic temperature control systems. KELVIN & HUGHES Ltd. Jan. 27, 1956 [Oct. 29, 1954], No. 31301/54. Class 38 (4). In an apparatus for controlling the supply of fuel to a furnace and comprising a motor 9 having a speed regulator 12 which is adjustable by a reversible A.C. servomotor 13 under the control of a mercury switch 23 attached to a pivoted member 27, the member is actuated by a bar 28, 29 which is urged in one direction by a bimetallic element 33 in response to an electrical signal from a master controller and in the other direction by an electromagnet 30 energized by a current due to the armature B.E.M.F. proportional to the speed of the motor 9. The electromagnet may alternatively be energized by a tachometer generator, attached to the motor shaft. In modifications, Figs. 2, 3 (not shown), the bimetallic strip is replaced by a motor-driven cam and the member 27 is replaced by a solenoid controlled pivoted bar respectively.</p> |
