Section 36.—EXPANDING AND CONTRACTING DEVICES.
(See also [p. 84].)
[2142]. Expanding gate. Formed of vertical, round, or simple bars, fitted with sliding ferrules having centre pins passing through diagonal bars, these centres being evenly spaced.
[2143]. Expanding mandrel; has three parallel feathers, expanded by a central bolt having two equal cones.
[2144]. Expanding socket, formed of spring wire.
[2145]. Expanding legs for telescope or camera tripod.
[2146]. Expanding tripod, formed to close up into a cylindrical group.
[2147]. Expanding table of three or more slides.
[2148]. Expanding tripod. The legs are hinged to a triangular prism, and form a cylindrical group when closed.
[2149]. Expanding reamer. The body is split up in three parts as far as the end of the bolt.
[2150]. Addy’s expanding collar consists of two rings with the adjacent faces spiral, so that by revolving them they separate to the extent of the pitch. The collar therefore expands longitudinally, not diametrically.
[2151]. Expanding split reamer or mandrel with taper screw.
[2152]. Expanding riddle or screen, to vary the spaces between the bars.
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[2153]. Expanding collars or sleeves, screwed one upon another.
[2154]. Expanding collet, split in three or more parts.
[2155]. Expanding pipe grip or collar with bevel gear and right and left-hand screws to operate the three segments together.
[2156]. Expanding pipe stopper with rubber ring. See [Section 29].
Bellows and rubber bags are used as expanding devices for gases, &c.
Rubber balloons are expanded by air blown in under pressure.
[2157]. Expanding pulley or wheel.
Expanding plug. See [No. 2358].
[2158]. Expanding lever.
The mercury bulb tube is an expanding device actuated by temperature.
(See also [Cushioning]; Chucks, [Section 28].)
Section 37.—FASTENING WHEELS, &c., TO SHAFTS.
(See also [p. 86].)
[2159]. Crank arm or lever arm, secured to shaft by a clip boss and bolt.
[2160]. Ditto, secured by a screwed shank passed through the shaft and drawn up by a nut.
[2161]. Piston and rod fastening.
[2162]. Ditto, ditto.
[2163]. Thomas’ patent wedge bush for securing plain bored pulleys, &c., to shafts.
[2164]. Taper screwed bush fastening for a wheel, with frictional grip. The bush is split on one side only.
[2165]. Taper split bush fixing, with frictional grip. The bush is split into three parts.
[2166]. Set-screw fixing for a lever or arm.
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[2167]. Split boss or collar, with two forms of sunk screws for fixing and tightening.
Split wheels and pulleys are now commonly used as the best means of fastening to shafts. See [No. 1711].
[2168]. Cone sleeve (split) and nut fastening for a wheel or pulley.
[2169]. Serrated wedges.