Twentieth century hand-book for steam engineers and electricians with questions and answers; a practical non-technical treatise .. (1913)
Swingle, Calvin Franklin, 1846- [from old catalog] · Chicago, F. J. Drake & company · leaf 1071
mo is very weak, the resistance of the ^^short cir-cuit^^ formed by the dynamo brush is also very weak andtherefore the current may be quite strong. This current isthe main cause of sparking in dynamos. The num.ber ofbars constituting a commutator depends upon the windingof the armature, and the… … Fig. 435a single coil armature of many turns there are many reasons against making the number of barson a commutator very great. Increasing the number ofbars in a commutator increases the cost of manufacture,and in sm.aller dynamos, if the number of bars be increasedbeyond a certain extent, each…
