Mechanical-advantage synonyms

The circular system is developed continuously over the entire subumbral surface, and the velum represents a special local development of this system, at a region where it is able to act at the greatest mechanical advantage in producing the contractions of the umbrella by which the animal progresses.

2, it will be balanced by a thrust W lb applied to the other piston of area B ft.', where p = P/A=W/B, (I) the pressure p of the liquid being supposed uniform; and, by making the ratio B/A sufficiently large, the mechanical advantage can be increased to any desired amount, and in the simplest manner possible, without the intervention of levers and machinery.

The value d/D usually lies between the limits io/i i and 15/16, and, if a greater difference of E from R is required, a further mechanical advantage can be obtained by employing a separate hand-wheel and chain, or by forming the upper sheave with an annular spurwheel gearing with a pinion driven by a hand-wheel and chain, as in the Tangye form of Weston pulley-block.

The worm-wheel shaft then sometimes carries a spur-pinion gear ing with a spur-wheel on the lifting shaft, whereby a much greater mechanical advantage is obtained with a small loss by friction of the spur gearing.