Section 21.—CIRCULAR AND RECIPROCATING MOTION.
(See also [p. 56].)
[2022]. The “Dake” square piston engine; has a reciprocating double piston and a transverse sliding block, by which rotary motion is communicated to the crank pin.
[2023]. Chapman’s patent crank motion. In this gear the cylinders are fixed at right angles and their strokes are four times the radius of the crank, which is coupled by a link with equal arms (of the same radius as the crank) to the two crossheads direct.
[2024]. Crank motion. The crank pin runs in a sleeve having a sliding motion along the lever.
[2025]. Crank motion (in plan), with side connecting rod and off guide. The crank shaft crosses the piston rod as near as may be.
[2026]. Crank motion, with semi-yoke crosshead.
[2027]. Crank motion, with yoke connecting rod.
[2028]. Crank motion, for a pump, the handle describes an elliptic path.
[2029]. Bouchet’s crank motion to avoid dead centres.
[2030]. Eccentric hand crank motion. The connecting rod has a ring-shaped end, and the strap is revolved on the centre pin by a handle fixed to it.
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[2031]. Crank motion to work a sliding tool or movement on a bar or guide.
[2032]. Offset crosshead and guide crank motion for a pump or air compressor.
[2033]. Crank motion to drive a swing arm, or vice versâ.
[2034]. Side crank motion.
[2035]. Atkinson’s crank motion to drive the flywheel two revolutions to one double stroke of the piston.