. Railway and locomotive engineering : a practical journal of railway motive power and rolling stock . June. 1922 RAILWAY AND LOCOMOTIVE ENGINEERING 149 W Ian tlie engine is fitted with a valvehaving inside admissions, as is shown inFig. 20, the point (/ of the lap-and-leadlever is usually alwve //, that is the points// and (/ have changed places. The different positions of the point Gat the time of the closure of the valve forthe dilTerent points of cut-otT are obtainedill the same manner as for the valve withan outside lap except that the arcs ofcircles struck from d and d as centers andwith
. Railway and locomotive engineering : a practical journal of railway motive power and rolling stock . June. 1922 RAILWAY AND LOCOMOTIVE ENGINEERING 149 W Ian tlie engine is fitted with a valvehaving inside admissions, as is shown inFig. 20, the point (/ of the lap-and-leadlever is usually alwve //, that is the points// and (/ have changed places. The different positions of the point Gat the time of the closure of the valve forthe dilTerent points of cut-otT are obtainedill the same manner as for the valve withan outside lap except that the arcs ofcircles struck from d and d as centers andwith H as a radius are not drawn belowbut above their centers as shown inFig. 24. It is also to be noted that for a valvewith an inside admission, that half of thecircle e + v„ to the left of H^ is for theback port, while that to the right is forthe front port, which is just the reverse ofwhat obtains when outside admission isused. In order that the point of cut-ofif may beat the commencement of the stroke the. valve must close the port when the pistonis at the points 0/X and O/IO respectively,that is when it is at the ends of the is impracticable because of the linearlead, and because of which the point G,falls at the same place for both ends ofthe stroke of the piston and for all pointsof cut-ofT. If the given throw of the eccentric ris laid down on the drawing from O,(Fig. 1) it is possible, in view of the ex-amples already given, to proceed in thesame manner with the determination ofthe radius c of the point D of the link aswell as of the position of the pivotal pointE. and the point of attachment D for theeccentric rod. After these points havebeen determined and laid down .the posi-tions of the link, corresponding to thevarious points of cut-of? or the positionsof the piston, can be located. This is doneas follows: Draw a straight line connecting D andO and at O (Fig. 29) draw a line at rightangles to the same, cutting the circle, de-scribed from O as a center an
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