. Mechanical appliances, mechanical movements and novelties of construction; a complete work and a continuation, as a second volume, of the author's book entitled "Mechanical movements, powers and devices" ... including an explanatory chapter on the leading conceptions of perpetual motion existing during the past three centuries. 248 MOTION AND CONTROLLING DEVICES, 644. CHANGE SPEED PULLEYS. Lazy-tongs type. The de-vice comprises two pulleys, A and B, the rims of which are made in sec-tions so that their diameters■ML—. can be varied. By turning the crank C the diameter ofA is altered, wh
. Mechanical appliances, mechanical movements and novelties of construction; a complete work and a continuation, as a second volume, of the author's book entitled "Mechanical movements, powers and devices" ... including an explanatory chapter on the leading conceptions of perpetual motion existing during the past three centuries. 248 MOTION AND CONTROLLING DEVICES, 644. CHANGE SPEED PULLEYS. Lazy-tongs type. The de-vice comprises two pulleys, A and B, the rims of which are made in sec-tions so that their diameters■ML—. can be varied. By turning the crank C the diameter ofA is altered, while that of Bchanges under pressure ofthe helical springs surround-ing its axle, thus keepingthe tension of the belt prac-tically constant. The rim sections or shoesof these pulleys are supportedupon a felly, or frameworkformed of two lazy tongs joined at their summits and pivoted together atthe middle of their branches so as to form a series of equal diamondswhich must all elongate or flatten simultaneously. 645. MULTIPLE-SHAFT DRIVING DEVICE. The four crankpins are pivoted on an oscillating and sliding sleeve on a central post, as shown in the planand vertical shaft may bethe driver. All theshafts must be at rightangles with each other,and in the same planefor perfect action. 646. Vertical sec-tion showing centralsliding post. 647. RECIPROCAT
Size: 1806px × 1383px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorhiscoxgardnerdexter18, bookcentury1900, bookdecade1910
