Pulley

3 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Pulley \Pul"ley\, n.; pl. {Pulleys}. [F. poulie, perhaps of
     Teutonic origin (cf. {Poll}, v. t.); but cf. OE. poleine,
     polive, pulley, LL. polanus, and F. poulain, properly, a
     colt, fr. L. pullus young animal, foal (cf. {Pullet},
     {Foal}). For the change of sense, cf. F. poutre beam,
     originally, a filly, and E. easel.] (Mach.)


     A wheel with a broad rim, or grooved rim, for transmitting
     power from, or imparting power to, the different parts of
     machinery, or for changing the direction of motion, by means
     of a belt, cord, rope, or chain.
     [1913 Webster]
  
     Note: The pulley, as one of the mechanical powers, consists,
           in its simplest form, of a grooved wheel, called a
           sheave, turning within a movable frame or block, by
           means of a cord or rope attached at one end to a fixed
           point. The force, acting on the free end of the rope,
           is thus doubled, but can move the load through only
           half the space traversed by itself. The rope may also
           pass over a sheave in another block that is fixed. The
           end of the rope may be fastened to the movable block,
           instead of a fixed point, with an additional gain of
           power, and using either one or two sheaves in the fixed
           block. Other sheaves may be added, and the power
           multiplied accordingly. Such an apparatus is called by
           workmen a {block and tackle}, or a {fall and tackle}.
           See {Block}. A single fixed pulley gives no increase of
           power, but serves simply for changing the direction of
           motion.
           [1913 Webster]
  
     {Band pulley}, or {Belt pulley}, a pulley with a broad face
        for transmitting power between revolving shafts by means
        of a belt, or for guiding a belt.
  
     {Cone pulley}. See {Cone pulley}.
  
     {Conical pulley}, one of a pair of belt pulleys, each in the
        shape of a truncated cone, for varying velocities.
  
     {Fast pulley}, a pulley firmly attached upon a shaft.
  
     {Loose pulley}, a pulley loose on a shaft, to interrupt the
        transmission of motion in machinery. See {Fast and loose
        pulleys}, under {Fast}.
  
     {Parting pulley}, a belt pulley made in semicircular halves,
        which can be bolted together, to facilitate application
        to, or removal from, a shaft.
  
     {Pulley block}. Same as {Block}, n. 6.
  
     {Pulley stile} (Arch.), the upright of the window frame into
        which a pulley is fixed and along which the sash slides.
        
  
     {Split pulley}, a parting pulley.
        [1913 Webster]

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Pulley \Pul"ley\, v. t.
     To raise or lift by means of a pulley. [R.] --Howell.
     [1913 Webster]

From WordNet (r) 2.0 [wn]:

  pulley
       n : a simple machine consisting of a wheel with a groove in
           which a rope can run to change the direction or point of
           application of a force applied to the rope [syn: {pulley-block},
            {block}]