Section 36.—EXPANDING AND CONTRACTING DEVICES.
Common expedients for these purposes are—jointed folding rods, as a carpenter’s rule; the telescope tube; net work; diagonally crossed and jointed bars; lattice work; springs (see [Section 80]); lazy tongs ([No. 623]).
[616]. Telescopic ram hydraulic lift. (See also [No. 1217].) Consisting of two or more rams sliding within each other.
[617]. Parallel bar expanding grille, or gate.
[618]. Parallel bar expanding grille, with lazy tongs motion, each alternate bar has slotted holes as shown.
[619]. Modification of [618]. The number of horizontal bars can be multiplied indefinitely.
[620]. Venetian blind; this method is used also for movable doors or partitions, sliding horizontally.
[621]. Venetian blind, but without revolving motion to the laths or slats.
[622]. Perforated bar and hooked rod suspender.
[623]. Lazy tongs expanding connecting rod.
[624]. Four-guide expanding link device, for varying motion.
[625]. Thorburn’s tube expander, operated by a central cone and ring of conical rollers.
[626]. Gasometer.
[627]. Timms’ expanding boring tool. Operated by a central cone and three or more diagonal feathers, sliding in dovetail grooves in the central cone.
Expanding Mandrel, [No. 507].
Expanding Chucks, [Nos. 489], [491], & [506].
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[628]. Expanding basket, with chain corner suspenders.
[629]. Expanding socket, with sliding ring grip.
[630]. Expanding grating, formed of bent steel laths on edge.
[631]. Bridge or flap between cars, having buffers.
[632]. Expanding core barrel, in three parts, expanded by a wedge.
[633]. Expanding mandril or chuck. See also [Section 28].
Expansion Joint, [Nos. 1076], [1077].
Expanding Pipes, [No. 1079].