| 摘要 |
881,072. Commutators for dyanmo-electric machines. FIAT S.p.A. June 23, 1959 [Jan. 19, 1959], No. 21527/59. Class 35. [Also in Group XXII] A method of manufacturing a dynamo-electric machine commutator comprises the steps of providing a copper lining plate 21, Fig. 3, throughout the length of the middle portion of one face of a rectangular base strip 20, machining a plurality of registering parallel cross slots 22 and grooves 23, Fig. 4, in the respective strip 20 and plate 21 starting from the bare face of the former, opening the ends of the slots 22, Figs. 5, 6, by removing material from the marginal zones of the strip 20 thereby subdividing the strip into a plurality of cross tongues 20<SP>11</SP> the intermediate portion of each of which is bonded to the plate 21, bending to hook form, Fig. 7, the ends 25 of the tongues 20<SP>11</SP>, cylindrically curving the plate and strip so that the hookform ends 25 are within the cylinder thus formed, filling the cylinder with a thermosetting electrically insulating material 32, Fig. 11, to embed the hook-form ends 25, and machining on a lathe the cylindrical surface of the resulting unit to remove the lining plate 21 down to the grooves 23 thereby subdividing the plate into electrically separated segments 21a. The strip may be of steel and the plate may be applied by electrolytic deposition, coating, or plating, the thermosetting material may be a phenol or urea resin preferably mixed with a fibrous filler e.g. of glass or cotton. To receive armature winding leads not shown a notch 33 is milled in each segment. Specification 879,599 is referred to. |
