| 摘要 |
479,621. Electromagnets. BRITISH THOMSON-HOUSTON CO., Ltd. Oct. 17, 1936, No. 28276. Convention date, Oct. 17, 1935. [Class 35] [Also in Group XXXVII] An electromagnet core 10 of soft-iron laminations comprises a readily - saturable part 13 of small crosssection, and a part 14 of large cross-section having an air-gap 14<1>. A coil 15 embracing a limb of the core is mounted on an insulated rod 17 slidable in the core and carrying a contact 18. With low currents in the coil the flux is confined to the path 13 and does not traverse the gap, and the coil is consequently moved so that contact 18 closes the circuit of a minimum-current indicator G. With large coil-currents, path 13 becomes saturated and an increase of flux in the gap occurs, so that the coil is moved towards the gap and contact 18 energizes a maximum-current indicator R. Light springs 15<11> centre the coil. |
