. Modern mechanism, exhibiting the latest progress in machines, motors, and the transmission of power, being a supplementary volume to Appletons' cyclopaedia of applied mechanics . tential at brushes = 103 volts; speed in revolutions perminute = 620; temperature of air = 60° F.; highest temperature of armature = 140° F.;highest temperature of magnet-coils = 125° F. The Mather and Hopkinson Dynamo, an excellently designed machine, is illustrated inFigs. 61 and 62. The armature, designed by Dr. J. Hopkinson, F. R. S., and Dr. EdwardHopkinson. is a modified Gramme, with low resistance and careful
. Modern mechanism, exhibiting the latest progress in machines, motors, and the transmission of power, being a supplementary volume to Appletons' cyclopaedia of applied mechanics . tential at brushes = 103 volts; speed in revolutions perminute = 620; temperature of air = 60° F.; highest temperature of armature = 140° F.;highest temperature of magnet-coils = 125° F. The Mather and Hopkinson Dynamo, an excellently designed machine, is illustrated inFigs. 61 and 62. The armature, designed by Dr. J. Hopkinson, F. R. S., and Dr. EdwardHopkinson. is a modified Gramme, with low resistance and careful ventilation. The collectoris unusually substantial, and consists of 40 bars of toughened brass insulated with mica. Itis usual in these machines so to shape the pole-pieces that there is a smaller clearance oppo-site the highest and lowest points of the armature; this concentrates the magnetic field, andhelps to prevent its distortion by the armature-current. In a 24-unit machine (designed for300 lamps) of this pattern the armature-cores are 12 in. long and 12 in. in diameter, with 120turns of wire. The resistances are: Armature, 023 ohm; .shunt, 19-36 ohms: series-cod,. Jy di naiiiu. 222 DYXAMO-ELECTRIC MACHINES. •013 ohm. With a speed of revolutions per minute the current was 220 amperes, themachine being nearly self-regulating for 111 volts. This machine is known as the Man-chester dynamo. Its efficiency is 909 per cent.
Size: 1486px × 1681px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade189, booksubjectmechanicalengineering
