. The strength of materials; a text-book for engineers and architects. nedy; most other machines are basedupon the same principle. A graduated lever a is counter-weighted to balance about a knife-edge B coaxial with thespecimen x, which usually has the form shown in Fig. 167 (6)with the exception that the ends are not jockey-weight \v runs along the lever and the specimen isclamped in a chuck which is connected to the lever at thepomt c. The other end of the specimen is secured by achuck carried by a worm-wheel d which is operated througha Avorm from a handle e to apply the ne
. The strength of materials; a text-book for engineers and architects. nedy; most other machines are basedupon the same principle. A graduated lever a is counter-weighted to balance about a knife-edge B coaxial with thespecimen x, which usually has the form shown in Fig. 167 (6)with the exception that the ends are not jockey-weight \v runs along the lever and the specimen isclamped in a chuck which is connected to the lever at thepomt c. The other end of the specimen is secured by achuck carried by a worm-wheel d which is operated througha Avorm from a handle e to apply the necessary torque. Thejockey-weight is placed so as to exert a given torque, andthe handle e is turned until the lever floats between thestops s. 382 THE STRENGTH OF MATERIALS Professor Thurstons Torsion Machine. — In thismachine, Figs. 177, 178, the specimen is a short one withsquare ends, one of which is carried by a jaw rotated by wormgear, the other being carried by a jaw connected to a weightedpendulum, the angular movement of which determines thetorque X~ ^ Fig. 17G.—Torsion Testing Machine. An autographic diagram is obtained by securing a pencilto the pendulum in such a manner that the pencil movesparallel to the axis of the specimen as the pendulum swingsoutwards. A cylinder carrying a paper strip is secured tothe jaw carried by the worm-wheel. The paper thus rotatesby an amount equal to the angle of torsion, and the pencilmoves at right angles by an amount which is a measure of thetorque applied. THE TESTING OF MATERIALS 383 A templet of the form shown in Fig. 178 is employed toobtain a standard size of specimen. Averys Reverse Torsion IMachine.—Fig. 179 shows twoviews of a torsion machine, patented by Messrs. Avery, bymeans of which a torque can be applied in either direction.
Size: 2073px × 1206px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyorkdvannostran
