| 摘要 |
1,131,507. Electromagnets. W. BUCHHOLZ, [trading as STEINERT ELEKTROMAGNETBAU]. 8 Dec., 1965 [15 Dec., 1964], No. 52110/65. Heading H1P. In Fig. 3 an E-type electromagnet has end poles 31, 32 and centre pole 33 conjoined by a yoke 36 of ferromagnetic material wherein the centre pole and the end poles are enlarged and formed with recesses in which auxiliary exciting coils 34, 35 are wound, the main exciting coil 37 surrounding centre pole 33; the magnetomotive force at the pole faces being determined by the configuration and excitation of the auxiliary windings. Slits extend from the polefaces into the recesses housing the auxiliary coils. In Fig. 6, a cylindrical electromagnet has end pole portions 51, 52 and a centre pole portion 53 equidistantly spread therebetween; with a core 54 of ferromagnetic material conjoining the poles. Main excitation coils 55, 56 are wound on the core between the poles, and the end and centre poles are enlarged and formed with recesses in which auxiliary excitation coils 57, 58, 59, 61, 62, 63 are wound coaxially around the core. Plural slots extend from the cylindrical pole faces into the recesses, and excitation is arranged to establish similar polarities over the respective surfaces of the end and centre poles, the end polarity opposing the centre polarity. The gaps may be filled with diamagnetic material. The excitation current may be supplied over slip rings in series with control variable resistors. In a modification (Figs. 8-10, not shown) the end poles may embody no auxiliary windings but the centre pole may contain any desired number thereof in corresponding recesses, with any desired number of main excitation windings. In Fig. 11 an annular electromagnet comprises a yoke 71 of ferromagnetic material comprising a central pole 74 surrounded by an outer pole 72; the central pole having recesses accommodating coaxially wound auxiliary windings 78, 79 and a main winding 76 coaxially surrounding the central pole. The outer pole also has a recess accommodating auxiliary windings 77 coaxially surrounding the central pole. Gaps 81 to 83 are provided between the pole faces and the recesses. A lifting magnet (Figs. 13 to 16, not shown) may comprise outer poles having recesses accommodating auxiliary exciting windings. |
