Chapter XLVIII: Section 55: Parallel Motions

Purpose: to maintain rectilinear motion of a rod or equivalent detail coupled to a lever without employing guide bars.

=1009. Watt’s parallel motion= for a beam engine.

=1010. Rack and segment motion.=

=1011. Epicycloidal parallel motion.= The pinion is one-half the diameter of the wheel at the pitch lines, and the gudgeon is fixed upon the pitch line of the pinion.

=1012. Peaucellier’s parallel motion.= ~A~ is a fixed centre; ~B~ (for _parallel_ motion) must be one-half way to ~C~; power is applied to ~C~; ~D~ parallel centre gudgeon.

=1013. Beam,= with rocking fulcrum. ~A~ ~A~ are equal, as also ~B~ ~B~.

=1014. Single radius bar and link;= the radius bar to be same length as the half beam and the link hinged on its centre.

=1015. All the radius bars to be of same length= as the half beam.

=1016. Two equal radius bars= connected by a link, the main gudgeon in its centre.

=1017. Beam of the 2nd order= with rocking fulcrum, ~A~ and ~A~ being equal.

=1018. Sector and rack motion.=

See also No. 714.