The wonders of modern mechanismA résumé of recent progress in mechanical, physical, and engineering science . involved is this : Ifwe take a cylinder of water standing on end, aud place aweight upon an absolutely tight plunger ou top of thewater, and if we have a hole in the bottom of the cylinderwhose diameter is one thousandth of the top aperture ofthe cylinder, upon which the weight rests, and if we thenmeasure the pressure of the water at the little hole in thebottom, we have only to multiply it by oue thousand toget the weight of the load on the cylinder. The means by which Mr. Emery prod
The wonders of modern mechanismA résumé of recent progress in mechanical, physical, and engineering science . involved is this : Ifwe take a cylinder of water standing on end, aud place aweight upon an absolutely tight plunger ou top of thewater, and if we have a hole in the bottom of the cylinderwhose diameter is one thousandth of the top aperture ofthe cylinder, upon which the weight rests, and if we thenmeasure the pressure of the water at the little hole in thebottom, we have only to multiply it by oue thousand toget the weight of the load on the cylinder. The means by which Mr. Emery produced an absolutelytight cylinder operating without appreciable friction arevery ingenious, and wall be understood by examining theaccompanying diagram of the weighing mechanism. A isthe hydraulic-support cylinder, the white space represent- THE EMERY TESTING-MACHINE. 383 ing water; c is the piston, and 6 and del are thin sheets ofmetal. The piston rests on the lower sheet, and is securedto tlie cylinder by the sheets dd, which are flexible, al-lowing a movement of perhaps three thousandths of an Fig. DETAILS OF WEIGHING MECHANISM. inch, which is all the motion needed between a full loadand no load. By this arrangement the fluid is entirelyenclosed, and no packing is required, and the friction is allin the fluid. A tube connects the water-chamber of thehydraulic support with a smaller and similar chamber, piston c of this latter chamber acts through the blockH against the first lever C of the scale, which thus receives afraction of the load upon the piston c, of the large cylinder,determined by the diiference in size between the two hy-draulic cylinders A and B, which in practice is muchgreater than that shown in the diagram. At the upper left hand of the larger figure in the diagramy 384 WOXDERS OF MODERN MECHANISM. will be observed a row of figures, aud an upright scalemarked by a long needle, F. When the hydraulic cylindersexert a pressure upon the first lever (7
Size: 1926px × 1298px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, booksubjectmachinery, booksubjectmechanicalengi
