. The steam-engine and other heat-motors . exerted vertically atB and Bx, let the linkage attain the dotted position. Either analyt- REVOLUTION CONTROL. 331 ically or graphically it will be found that if the balls B, Bi movethrough a small vertical height (dh), the heavy weight L will movea greater height, k(dh). The work put in must equal the work done. .. 2P(dh)=2wdh+Lk(dh).kh P = w + 2 If the upper and lower arms are of the same length, k = work will evidently be zero. The r*. t*T7—*. *F. Fig. 170. Let the mechanism shown be that of a loadsd high-speedgovernor. Let centrifugal
. The steam-engine and other heat-motors . exerted vertically atB and Bx, let the linkage attain the dotted position. Either analyt- REVOLUTION CONTROL. 331 ically or graphically it will be found that if the balls B, Bi movethrough a small vertical height (dh), the heavy weight L will movea greater height, k(dh). The work put in must equal the work done. .. 2P(dh)=2wdh+Lk(dh).kh P = w + 2 If the upper and lower arms are of the same length, k = work will evidently be zero. The r*. t*T7—*. *F. Fig. 170. Let the mechanism shown be that of a loadsd high-speedgovernor. Let centrifugal force F, acting along EB and EBifkeep the balls in the dotted position shown. Then, for the reasonsabove given, we have, taking moments around A, Pr = Fh, or / kL\ wV21\ 2 / gr This equation contains apparently six variables, five of whichmust be given to determine the remaining one. Suppose L = 0, 332 THE STEAM-ENGINE AND OTHER HEAT-MOTORS. This gives the equation of the simple pendulum governor, wy2 v2 r2 wr = h or — = -r. gr g h In this equation the weight of the balls B and Bx has entirely-disappeared. Hence, theoretically, if there were no such effectsas friction and inertia, and if certain very necessary parts had noweight, we could use balls of any weight whatever. Practically,as there is considerable friction in valve-stem packing, as heavyparts must be given motion quickly and as connecting links havenecessary weight, the balls are generally made of considerableweight, depending on
Size: 1264px × 1977px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublisheretcetc, booksubject
