. Electrical world. n Figs. 15 to 17 these strains are still higher as b is to be replacedby the larger value, b and 2 in the denominator by or i. These examples may be sufficient to give an idea of the excessivestrains which exist in high-speed field bodies. 4. Finally a few words about noiseless running. It is generallyknown that all extra high-speed machines have a certain tendencyto produce a penetrating, shrill or droning noise, which renders everyconversation impossible, and which may be heard over a great dis-tance. The cause is the very rapid air movement, especially thewhirls and
. Electrical world. n Figs. 15 to 17 these strains are still higher as b is to be replacedby the larger value, b and 2 in the denominator by or i. These examples may be sufficient to give an idea of the excessivestrains which exist in high-speed field bodies. 4. Finally a few words about noiseless running. It is generallyknown that all extra high-speed machines have a certain tendencyto produce a penetrating, shrill or droning noise, which renders everyconversation impossible, and which may be heard over a great dis-tance. The cause is the very rapid air movement, especially thewhirls and sudden variations of the section of the streaming air byprojecting and overhanging windings or other parts of the insufficiently fixed in the slots or laminated teeth not well 598 ELECTRICAL WORLD and ENGINEER. Vol. XLIII, No. 13. pressed together may magnify the noise considerably. The bestremedy consists in designing an absolutely smooth drum or rotating The Letter of Peregrinus on the Magnet, FIG. 18.—GENER.\L ELECTRIC METHOD OF COMBINING POLES .\XD POLESHOES. part which can easily be done for the types of Figs. 9 and 10. Definitepole types have to be very often to be entirely closed by cylindrical
Size: 1847px × 1353px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectelectri, bookyear1883
