Motion may be conveyed to such parts of a machine as require to be
movable, or to distinct machinery which has no fixed location, by the
following means:--
=441. Is an endless rope or other round section belt,= kept tight in any
position in the plane of the driving pulley by a weighted pulley. In
this plan the machine can be moved to any position in the plane of the
driving pulley, the weighted pulley taking up the slack of the belt.
=442. Flexible shaft for light driving.= It admits of considerable
flexure, and is useful for drilling and similar incidental driving
purposes in difficult positions.
=443. Radiating arm and belt.= The movable machine can be driven at any
point in circumference of the circle described by the arm head.
=444. Similar plan,= but driven by bevil gear instead of belt.
=445. Bevil gear and feather shaft.= The movable machine having a travel
in a straight line the length of the shaft as well as a radiating
motion.
[Illustration: 428.-445.]
=446. Screw and worm wheel gear,= for the same purpose as 445.
=447. The driven wheel= ~A~ has a limited travel up and down the slot,
the idle wheel ~B~ being kept in gear by the link suspension.
=448. Idle wheel and slot.= A common device for changing direction or
speed in driving gear by connecting or disconnecting it with
intermediate gearing between a fixed driving and a driven shaft.
=449. Parallel motion radiating driving device,= with a limited vertical
travel and a radial motion.
=450. Motion by belt= is conveyed to a driven shaft having a radial
motion in a vertical plane. Used for light drilling, emery wheels, &c.
=451. Steam or hydraulic radiating arm= and cylinder device.
=452. Central cylinder= and radiating lever motion.
=453. Jointed radiating arms,= with belt gear for conveying motion from
a central spindle to one having a travel covering any point within a
circle of the extreme radius of the jointed arms.
See also Nos. 348, 349.
Endless rubber or wire coil belts are used to give motion to machines
having some amount of freedom of movement as regards the fixed
position of the driving pulley.