. American engineer and railroad journal . n and thus of quickly obtaining relativevalues, which are all that are at present desired. On the line L L lay off A C(fig. I) to any convenientscale, so that it represents the pulling force according to acertain ratio. If then the dotted lines i?/) and CZ?aredrawn parallel to A C and A B respectively, a parallelo-gram, A B C D, will be formed, from which, by the well-known principle of the parallelogram of forces, the forces * The effect of frictional resistance at the bearing surface of the loclc inmodifvine the intensities anH directions nf the for
. American engineer and railroad journal . n and thus of quickly obtaining relativevalues, which are all that are at present desired. On the line L L lay off A C(fig. I) to any convenientscale, so that it represents the pulling force according to acertain ratio. If then the dotted lines i?/) and CZ?aredrawn parallel to A C and A B respectively, a parallelo-gram, A B C D, will be formed, from which, by the well-known principle of the parallelogram of forces, the forces * The effect of frictional resistance at the bearing surface of the loclc inmodifvine the intensities anH directions nf the forces .ictineatthe lock andpivotal pin. as will be siihseqiiently seen, is consWerable. But in the presentinstance the results to be obtained are simply relative, and as the generaleffect of friction is similar in eaclj case to be talten up it may he entirelyneglected, and in no way detracts from the practical value of these effect of friction will, huwever, be luHy explained later on. Vol. LXVI. No. ENGINEERING JOURNAL. 167. acting at the lock and pivotal pin are at once found. Thusthe force at the pivotal pin acis alonj; the line A O in thedirection indicated by the arrow, and its intensity Is repre-sented by the line ,/ IJ meas-ured by the same scale adopt-ed for A C. In Wkc mannerthe direction and intensity ofthe force acting against thelock is given by the line .-/ B. By a similar method, if thebuffing force is taken as act-ing at Q along the line S S,the resulting force at the piv-otal pin and point of resist-ance in the drawhead J/mayat once be determined from theparallelogram ) / A 5, and bymodifying the positions of thelock, pivotal point and point ofresisting a buffing force in thedrawhead, relative to eachother and to the lines of actionof the pulling and buffingforces, the Intensities and di-rections of the forces producedat these three points may alsobe determined for differentconditions. Figs. 4, 5, 6 and 7 repre-sent in this respect examplesof pract
Size: 878px × 2848px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectrailroadengineering
