Plate 7Larger plate.
Larger plate.
124. Base platefor column, &c., with concrete foundation. The bolts are usuallyTheaded (seeNo. 1404), in open recesses, so as to be easily removed without disturbing the base plate.
125. Dovetail and key fixingfor brackets, bearings, or any separate detail of framing.
126. Foundation for box bedplates.
127. Vertical columnar,or distance rod construction, used for marine engines, vertical engines, presses, &c.
128. Plinth, column, entablature, and cross bracing,used for beam engines and machinery of a straggling kind with many detached parts.
129. Flat bar side framing,strong, light, and cheap, but not very rigid.
130. Wrought-ironLand flat bar rectangular frame,suitable where great rigidity is not needed, but where cast-iron is not safe or desirable.
Wrought-iron is becoming much more largely employed for the framing of general machinery than heretofore, and it is customary in many cases to supplement a cast iron base or frame with wrought iron or steel bars.
For producing, from plain circular, or reciprocating motion, variable speed or motion, also intermittent and every kind of irregular motion. Cams are either open or covered.Nos. 131, 132, and 133are open cams;Nos. 137and138, covered cams.
131,132, &133. Three forms of the “heart” cam,for giving a regular or intermittent vertical motion to a lever end.
134. Crown camfor vertical shaft.
135&136. Jumping cams.
137. Covered heart cam.
138. Covered crown cam.
139. Wiper and lever motion.
140. Twisted barwith sliding bush, which travels from end to end of the bar, and being prevented from turning, causes the bar to turn on its axis to the amount of its twist.
141. Crank pin and slotted lever;gives a variable speed with quick return.
Plate 8Larger plate.
Larger plate.
142. Spiral radius barfor opening valve. The valve is lifted off its seat by the radial motion of the lever against the inclined radius bar.
143. Crank pin and slotted lever motion,with slot arranged for irregular or intermittent motion.
144. Eccentric and slotted arm.The pin at the top of the arm has both a vertical and horizontal motion, causing it to trace an ellipse, the pin upon which the slot runs being fixed.
145. Wiper and lever motion,with rubbing plate; used for Cornish valves, &c.
146. Stamp mill.
147. Scroll cam.
148. Crank and lever,intermittent or continuous motion.
149. Piston, or valve rod and lever motion.
150. Similar movement,but with anti-friction roller on end of lever.
151. Rod and lever reciprocating motion,with anti-friction roller.
152. Similar movement,with a socket forged in the rod and the end of lever rounded to allow for angular motion.
153. Diagonal disc cam,or “swash plate.”
154. Motion for belt shiftingwith dead travel at half stroke. This allows the lever to move a certain distance on each side of the centre without moving the belt shifting bar.
155&156. Sectors and bent lever,used on Cornish engine valve gear.
157.Tlever valve motion,used in rock drills, some forms of steam engines, &c.
158. Four-bolt camplate,used for screwing dies, locks for fireproof safes, &c.
159. Slot, cam, and lever motion.
160. Barrel motionfor musical instruments, looms, &c., in which the barrel is provided with pins or staples to lift the respective levers.
Plate 9Larger plate.
Larger plate.
161. Drum with spiral vanesof long pitch, operated by a revolving arm on a shaft at right angles to the cam shaft, used for intermittent circular motion.
162. Volute and lever.
163. Double screw,for converting circular into reciprocating motion; has a right and left hand screw thread, and a shuttle attached to the lever end shaped to fit the thread, and capable of swivelling to turn the angle for reversing.
164. Eccentric ring and roller motion,for converting circular into reciprocating motion.
165. Triangular cam.Gives three reciprocations to the sliding bar in one revolution of the cam.
166. Fanfor giving motion to several rods or arms at one time, used for organ composition pedal movement, &c.
167. Crossed lever motionwith inclined contact surfaces, the levers being at right angles to one another.
168. Bent crankof round section; retains the fibre and strength of the metal.
169. Square forged crank.The crank arm is usually forged solid and the slot cut out by machine.
170. Built-up crank.There are other methods of building them. SeeMechanical World, December 1885. See alsoNo. 182.
171. Single crank,usually of wrought iron, but often made with cast-iron arm.
172. Disc crank.This form is generally adopted when cast iron is employed, and the counterbalance weight cast upon it, to balance the connecting rod, &c.
173. Counterbalanced single or double crank.
174&175. Two forms of crank pin eccentrics;sometimes used to drive the slide valve instead of the ordinary sheave and strap, asNo. 183.
176. Crank pin set in a boss formed on the driving wheel.
177. Double rod crank.
178,179, &181. Hand cranks.These should always be fitted with a loose ferrule of wood for the hand if possible, as much power is lost by the slipping of the hand to change its grip as the crank revolves.
180. Solid three-throw crank shaft,turned out of a solid forging.
Plate 10Larger plate.
Larger plate.
182. Built crank.Several modifications of this are in use for large marine shafts.
183. Solid sheave eccentric.
184&185. Split sheave eccentrics.
Largeeccentrics cause great loss from friction, unless provided with friction rollers in the sheave; but are sometimes used to avoid an additional crank in shaft.
186. Eccentric motionfor multiplying travel of eccentric by leverage.
187. Crank motion to turn an angleinstead of bevil gear and shaft, the cranks being of the form ofNos. 174or175.
188. Shifting or variable throw eccentric.The sheave is slotted to fit the shaft, and its throw is governed by a disc having a spiral slot and locking bolt.
189. Another form of shifting eccentric.The sliding block is arranged to lock in any part of the slot in the sheave.
190. Another form of shifting eccentric,in which the sheave is loose on an eccentric boss cast with the worm wheel, and is revolved by the worm, the bearings of which are fixed to the sheave.
See alsoNos. 606,712,720,728,729.
See alsoSections 40and79.
For Hooks, Swivels, &c., seeSection 43.
191. Ordinary long or short link chain.It is sometimes made to exact pitch to fit a snug or sprocket wheel. SeeNos. 1250&1251.
192. Stud link chain.
193. Flat chainfor use on flat rim double-flanged pulley.
194. Square link pitched chainfor sprocket wheel.
195. Stamped link pitched chainand special sprocket wheel.
196. Ordinary pitched link chain.Links drilled to templet.
197&198. Pitched chainsto drive wheels with ordinary and special teeth.
199. Another form of square link chain.
200. Stamped link chain, for light purposes.
201&202. Long link flat suspension chains.
203. Gib and cotter attachmentfor long link flat suspension chains.
Plate 11Larger plate.
Larger plate.
204&205. Drive chains.See Ewart’s patent, No. 2752-76, and others. These chains are replacing belts for many purposes, as they give a positive drive, do not stretch so much, and last longer, besides which they are easily detached at any point, and a damaged link can be readily replaced.
206&207. Thrust chains,with friction rollers at each junction, used in hydraulic multiplying cylinder gear in some cases.
208. Ewart and Dodge’s patent chain,with renewable seatings between the links.
The design and details of these must always be suited to circumstances. We only propose here to indicate the various types of under-framing and wheels in use, and to give sketch sections of bodies or cars for different purposes.
209. Two-wheel suspension carfor single rail or wire rope, used commonly on some kinds of cranes. SeeSection 18.
210,211,212, &213. Three-wheel cars.See also the various types of tricycles in use.
214,215,216, &217. Various forms of four-wheel under-frames,with and without swivelling bogies.
A car with four wheels arranged asNo. 217, but with the leading and trailing wheels slightly raised off the ground, is used as a goods car or hand truck, and is very readily swivelled about, running, of course, actually on three wheels only.
218. Five-wheel under-frame,with and without swivelling bogies.
219&223. Plans of six-wheel cars,with swivelling gear for curves; the centre pair having end play, swivel the leading and trailing axles by means of the jointed stays.
220. Plan of four-wheel car,with swivelling gear for curves.
221,222, &224. Six-wheel cars,the latter with leading and trailing swivelling bogies.
225. Eight-wheel double-bogie under-frame.This is the plan usually employed in long cars; each bogie is free to swivel independently, and is centrally loaded.
Plate 12Larger plate.
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226. Ten-wheel double-bogie under frame,the centre pair to have end play or broad flat tyres.
227. Twelve wheels and three bogies.The centre bogie must have end play, either as inNos. 222or226, or with transverse rollers between the bogie and frame.
Note that inNos. 221,223, &224the centre pairs, if running on rails, must have either end play in the bearings or flat broad tyres.
228. Open passenger car,either with transverse or longitudinal seats.
229. Covered passenger car,with either longitudinal or transverse seats.
230. Passenger car,with outside and central longitudinal seats.
231. Passenger car,with upper and lower longitudinal seats.
232. Passenger car,asNo. 231, but with seats reversed.
233. Passenger car,for one-rail railway.
234. Passenger car,similar toNo. 230, but with seats reversed.
235. American plan of passenger car,with transverse seats and central gangway.
236. Goods cars,low sided.
237. Covered or box wagon.
238. Hopper wagonfor discharging below.
239. Side discharge hopper wagon.
240. Side tip(or end tip)three-centre wagon.
241. Tip cart.
242. Tip wagon.
Plate 13Larger plate.
Larger plate.
243. Furniture wagon.
244. Grafton’s patent side tip wagon.
245. Long truck for boilers, &c.
246. Incline car for passengers.
247. Segmental swivelling bearings,used instead of a swivelling bogie and centrepin.
248. Hudson’s patent tip wagons,with three centres.
249. Hopper wagon,with central discharge.
250. Stamp mill,generally arranged in a battery of 4 or 6, for gold and other ores.
251. Stone-breaker,with chilled iron jaw faces and toggle or knapping motion. See Blake’s, H. R. Marsden’s, and other modifications in common use.
252. Double edge-runners.Sometimes driven below. In some designs the rollers revolve, and in others the pan revolves and the roller shaft is stationary.
253. Lucop’s patent centrifugal pulveriser.
254. Carr’s patent disintegrator.In this machine, each ring of bars is driven at a high speed in opposite directions inside a casing, the material being broken by the rapidity and intensity of the blows it receives.
255. Horizontal centrifugal roller mill.The material is crushed between the rollers and the shrouding of the pan by the centrifugal force of the rollers, which are suspended from a crosshead.
256. Cone roller mill,with vertical spindle.
257. Cone roller mill,with horizontal spindle and conical pan.
Plate 14Larger plate.
Larger plate.
258. Enclosed cone roller mill,with horizontal spindle and spirally grooved roller and casing.
259. Toothed sector mill.
260. Conical edge runner and pan.
261. Ordinary flour mill.The material is fed in the centre, passes between the stones, and falls out into the outer casing.
262. Rattle barrel,for cleaning and burnishing articles by mutual attrition; sand or emery is sometimes used to assist the process.
263. Ball and pan mill,for crushing ores, &c. The balls are carried round by a cross arm fixed to the central spindle.
264. Inclined ball and pan mill.
265. Oscillating mill.
266. Drum and roller revolving mill.
267. Cradle and roller mill.
268. Cone disc mill;the cones being inclined axially to one another, the material is crushed at the lower side of the cones.
269. Another form of stone breakerwith toggle motion.
270. Horizontal cone plate mill.
271. Revolving stamp and pan mill for ores.
272. Vertical cone mill.
273. Revolving pan and ball mill.
274. Planishing discsfor accurately rounding iron bars. See the patent rolled shafting in use, manufactured by the Kirkstall Forge Co. and others.
275. Vertical cone grinding and crushing mill.The vertical shaft has an eccentric motion at the footstep, giving a swaying rotatory motion to the grinding cone.
276. Crushing rollerswith spring bearing.
277. Centrifugal drill.The cross barAis alternately pressed down and allowed to rise, the strings winding on the spindle alternately in opposite directions by the momentum of the fly-wheel.