Forms: 1 cranc-, 5–7 cranke, 7– crank. [OE. cranc in cranc-stæf, ME. crank(e, a word rarely exemplified before the 17th c. App. an ablaut-derivative of the vb. crinc-an, cranc, crunc-en, found (but very rare) in OE. as a by-form of cring-an, crang, crung-en to fall in battle, of which the primitive meaning appears to have been ‘to draw oneself together in a bent form, to contract oneself stiffly, curl up.’ These verbs are not known elsewhere in Teutonic; but numerous derivatives occur in the other languages, connected with the two notions of ‘to bend together, crook, curl up,’ and ‘to shrink, give way, become weak or ill.’ Eng. crank belongs to the literal sense-group, with the primary notion of something bent together or crooked; Ger. and Du. krank adj. ‘sick,’ formerly ‘weak, slight, small,’ shows the figurative development.]
1. A portion of an axis bent at right angles, used to communicate motion, or to change reciprocal into rotary motion, or the converse.
a. In early times chiefly used as a handle or treadle to turn a revolving axis by hand or foot.
c. 1000. Gerefa, in Anglia, IX. 263. Wulcamb, cip, amb, crancstæf.
c. 1440. Promp. Parv., 100. Cranke, instrument, cirillus (K. H. P. girgillus [= a reel for winding thread]). Ibid. Cranke of a welle, haustrum, haustra.
1617. Minsheu, Ductor, The Cranke or winch of a Well, L. Haustrum.
1660. R. D’Acres, Elem. Water-drawing, 11. Winches or Cranks of Wood or Iron are also fitted to mens hands, thereby to make a round motion.
1680. Moxon, Mech. Exerc., x. 88. [The fly wheel of the lathe] hath an iron axis with a Crook or Cranck at one end. Ibid. (1703), 233. Crank, the end of an Iron Axis turned Square down, and again turned Square to the first turning down, so that on the last turning down a Leather Thong is slipt, to Tread the Treddle-wheel about.
1734. Phil. Trans., XXXVIII. 403. A crank [of a pump] does not rise quite one third of its circle.
1877. N. W. Linc. Gloss., Crank, (1) the handle of a turnip-slicer, a ‘blower,’ a grindstone, or any similar machine.
b. Later, as a device for converting circular into reciprocal motion, and now chiefly (as in the steam engine) reciprocal into circular motion.
1727–51. Chambers, Cycl., Crank, a contrivance in machines in manner of an elbow … projecting out from an axis or spindle, and serving by its rotation to raise and fall the pistons of engines for raising water.
1731. H. Beighton, in Phil. Trans., XXXVII. 6. A quadruple Crank of cast iron.
1766. Specif. Barber’s Patent No. 865. 6. Three cylinders … work a treble or other crank.
1771. Watt, Lett., in Muirhead, W.’s Mech. Invent. (1854), II. 17. A crank of a sufficient sweep will be by much the sweetest motion.
1780. Specif. Pickard’s Patent No. 1263 A. B. represents a lever commonly called a crank … the pin of which crank is inserted into the end of a spear or carrier.
1862. Smiles, Engineers, III. 85. The connecting-rods gave the motion to two pinions by cranks at right angles to each other.
attrib. 1808. Watt, in Muirhead, W.’s Mech. Invent., III. 37. The true inventor of the crank rotative motion was the man … that first contrived the common foot lathe.
2. An elbow-shaped device in bell-hanging, whereby the rectilineal motion communicated to a bell-wire is changed in its direction, usually at right angles, as from horizontal to vertical or the reverse.
1759. Mountaine, in Phil. Trans., LI. 288. I found the bell-wire … to be intirely melted … but the effect ceased at the crank, which transmitted it to the chamber adjoining.
3. An elbow-shaped support or bracket.
1769. Falconer, Dict. Marine (1784), Crank, is also an iron brace which supports the lanthorns on the poop-quarters, &c.
1833. J. Holland, Manuf. Metal, II. 201. A semi-cylinder of wirework, balanced in its proper situation by means of two arms, or cranks.
c. 1850. Rudim. Navig. (Weale), 112. Cranks. Pieces of iron shaped as an elbow, &c., and attached to the beams of the quarter-deck for the capstan-bars to be stowed thereon.
4. A machine for the punishment of criminals sentenced to hard labor, consisting of a revolving disc to which a regulated pressure can be applied, and which the prisoner is required to turn a certain number of times each day.
1847. 2nd Rep. Surveyor of Prisons, 12. Means should exist of rendering the discipline … more stringent … by placing crank machinery in the cells.
1877. N. W. Linc. Gloss., Crank, (2) a machine used in some prisons for finding employment for refractory prisoners. There was one in the now disused prison at Kirton-in-Lindsey.
5. Sc. = CRAMP sb.2 4 b.
1825–79. Jamieson, Crank, an iron guard for the feet in curling, to prevent sliding on the ice. Roxb.
6. Comb., as crank-and-comb, a contrivance for stripping the carded cotton from a carding-engine; crank-axle, (a) the driving-axle of an engine or machine; (b) a carriage axle with the ends bent twice at a right angle, so as to lower the carriage-body and yet allow the use of large wheels (see CRANKED); crank-hatches (see quot.); crank-hook, the rod that connects the treadle and the crank in a foot-lathe; crank-pin, the pin by which the connecting-rod is attached to the crank; crank-shaft, the shaft driven by a crank; crank-wheel, a wheel that acts as a crank; esp. one having near its circumference a pin to which the end of a connecting-rod is attached as to a crank-pin; a disc-crank.
1836. Ure, Cotton Manuf., II. 35. This is the *crank-and-comb contrivance…. This elegant instrument takes off the cotton in a fine transparent fleece.
1725. Desaguliers, Exp. Philos. (1744), II. 516. [The wheels] are fitted to *crank axles, by which improvement the [Fire] engine runs upon larger Wheels, without raising the Cistern.
1887. Bury & Hillier, Cycling (Badm. Libr.), 377. Geared by chains to fixed pulleys on the crank-axle.
1867. Smyth, Sailor’s Word-bk., *Crank-hatches are raised coamings on a steamer’s deck, to form coverings for the cranks of the engines below.
1839. R. S. Robinson, Naut. Steam Eng., 86. The *crank pin is of wrought-iron.
1850. Weale, Dict. Terms, Crank-pin, the cylindrical piece joining the ends of the crank-arms, and attached to the connecting-rod, or, in vibrating engines, to the piston-rod: if the crank has only one arm, the pin projects from the end of it.
1854. Ronalds & Richardson, Chem. Technol. (ed. 2), I. 147. The rotation of the *crank-shaft will put in motion the bevel-wheels.
1794. Rigging & Seamanship, 54. *Crank-wheel, for spinning of lines, box-cord, &c. is fixed on an iron spindle.
