Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator . and the pitchLN; and the helix MJP, having the same diameter as LHN, isdrawn by dividing circle KR and pitch MP. Since the two circlesare drawn about the same center, the divisions on circle KR can be found by drawing radial lines from thepoints of division on circle IE. The ver-tical lines drawn from the divisions of thepitch AB can be used for the divisions ofL N; and those drawn from divisions of CDcan be
Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator . and the pitchLN; and the helix MJP, having the same diameter as LHN, isdrawn by dividing circle KR and pitch MP. Since the two circlesare drawn about the same center, the divisions on circle KR can be found by drawing radial lines from thepoints of division on circle IE. The ver-tical lines drawn from the divisions of thepitch AB can be used for the divisions ofL N; and those drawn from divisions of CDcan be used for MP. After the four parallel helices are drawn,it is necessary to study the drawing care-fully, to decide what lines will be visible(full lines) and what invisible (dotted lines).Dotted lines should be used from H to JfN to P, etc., and full lines from F to G, Bto D, etc. The line S T is the end of thespring, and consequently any part of a helixwhich goes outside of that line should notbe left on the finished drawing. It is better, however, to draw inthe whole of the square ACML, and to draw the helices startingfrom A to L, in order to draw those parts of the same helices. Fig. 58. Conventional Draw-ing for Spring of Round Wire MACHINE DRAWING 75 which lie to the right of ST. The parts to the left of S fareshown in the figure by light, dotted lines to indicate that theyare construction lines, and not a part of the projection of thespring itself. Conventional Representations of Springs. To draw springs bythe method just explained involves considerable work and wouldconsume a great deal of time if many were to be drawn; therefore,in working drawings, the draftsman commonly uses a conventionalmethod. This conventional drawing is similar to the true projec-
Size: 1209px × 2068px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublis, booksubjectmachinery
