GB1426217A - Transformer - Google Patents

Abstract

1426217 Transformers TRANSFORMATOREN UNION AG 21 Sept 1973 [21 Sept 1972] 44442/73 Heading HIT To avoid the transmission of magnetostrictive noise a transformer has its laminated iron core limb 8, primary winding 9, and secondary winding 10 radially spaced, the windings being supported at both ends 18, 19, 22, 23 by elastomeric spring members 20 compressed between ramming blocks 21 attached to the core yoke compression beams 12, 5, the resonant frequencies of the coil masses and spring rates being designed substantially below the magnetostrictive vibration frequency and preferably not exceeding one-third of that frequency. The coils may be supported at each end on a common spring member 20 having resilient axial extensions to maintain radial spacing as shown, or they may be individually supported by separate members (29, 30, Fig. 4, not shown), in which arrangement the coils may have different resonant frequencies within the aforementioned range. Preferably the coil offering the lesser acoustical damping is given the lower resonant frequency. The coil masses may be supplemented by added masses if necessary. The core laminations 8 are clamped together with bindings 11 comprising plastics or spunglass strips impregnated with casting resin cured after application. The core may be mounted on a frame 4 with elastic pads 2, 6. The coils are made rigid by pre-pressing and clamping, or by casting in resin 14.