释义 |
▪ I. cam, n.1|kæm| Also camb, camm. [cf. Du. kam (MDu. cam), Ger. kamm, Da. and Sw. kam, the same word as Eng. comb, but also applied to a ‘toothed rim or part of a wheel, teeth of a wheel’, as in Du. kamrad, Ger. kammrad, Da. and Sw. kamhjul ‘toothed wheel, cog-wheel’; thence also mod.F. came ‘cog, tooth, catch of a wheel, sort of tooth applied to the axle of a machine, or cut in the axle, to serve to raise a pestle or forge-hammer’. Taken into English prob. either from Du. or Fr. The primary meaning of Teut. kambo- was ‘toothed instrument’; cf. its cognates Gr. γόµϕο- tooth, peg, Skr. jambha- tusk, OSlav. ząbŭ tooth: see comb.] a. A projecting part of a wheel or other revolving piece of machinery, adapted to impart an alternating or variable motion of any kind to another piece pressing against it, by sliding or rolling contact. Much used in machines in which a uniform revolving motion is employed to actuate any kind of non-uniform, alternating, elliptical, or rectilineal movement. The original method was by cogs or teeth fixed or cut at certain points in the circumference or disc of a wheel, but the name has been extended to any kind of eccentric, heart-shaped, or spiral disc, or other appliance that serves a similar purpose.
1777Specif. W. Vicker's Patent No. 1168 The wheel F turning a cylinder with a cam and two crankes. 1805Specif. J. Hartop's Patent No. 2888 Upon any axis A..apply a pin, cam, crank or curve or curves C. 1831G. Porter Silk Manuf. 269 Camms, or wheels of eccentric form. 1832Babbage Econ. Manuf. vi. (ed. 3) 44 If one or more projecting pieces, called cams, are fixed on the axis opposite to the end of each lever. 1858Greener Gunnery 418. 1867 Athenæum No. 2084. 440/3 An iron camb for power-looms. 1879Cassell's Techn. Educ. I. 407/2 Cams are variously-formed plates, or grooves, by means of which a circular may be converted into a reciprocating motion. b. Comb., as cam-ball valve, cam-groove, cam-gear wheel, cam-shaft, cam-wheel. cam-box, a frame surrounding a cam and designed to compel the rod which the cam drives to follow the return motion of the projecting lobe; also, a casing enclosing the cam and its rollers in order that copious lubrication may be secured by having the cams revolve in a bath of oil (Cent. Dict. Suppl. 1909); cam-cutter, a machine-tool specially adapted for cutting and finishing cams; cam-pump, a pump in which the valve motion is given by a cam; cam-shaft, a shaft bearing a cam or cams; also attrib.; cam-yoke, a frame attached to a valve-stem or other reciprocating piece to which it gives intermittent straight-line motion from a cam on the face of a rotating disc; used in steam-engine valve-gears (Funk's Standard Dict. 1893).
a1884Knight Dict. Mech. Suppl. 156 Cam Cutter. 1922Jacobs Cam Design 74 The hand-made master cam is now placed in position on the cam cutter head spindle.
1879Cassell's Techn. Educ. IV. 393/1 A cam-groove cut in the reverse side of the crank-plate.
a1884Knight Dict. Mech. Suppl. 157 Drayton Cam Pump.
a1877― Dict. Mech. I. 435/2 Cam-shaft, a shaft having cams or wipers, for raising the pestles of stamping-mills. 1908Westm. Gaz. 9 Jan. 4/1 Depressing the cam-shaft pedal. 1955Times 20 Aug. 4/3 The new B.R.M. has a 2½-litre short stroke 4-cylinder engine with overhead cam-shafts.
1874Knight Dict. Mech. 435/2 The duty of the cam-wheel is to give an intermittent reciprocating motion to the bar. ▪ II. cam, n.2 north. dial. [= Sc. kame, kaim, a. ON. kamb-r (Da. and Sw. kam) comb, crest, serrated ridge, crest or ridge of a hill, etc. The same word originally as comb, and cam n.1, but the three come through distinct channels, and there is no consciousness of their identity.] A ridge; a long narrow earthen mound; the bank on which a hedge is planted or the like.
1788Marshall E. Yorksh. Gloss. (E.D.S.), Cam, any long mound of made earth. 1855Whitby Gloss., Cam, a mound of earth, a bank boundary to a field. 1861Ramsay Remin. Ser. ii. Introd. 26 (Yorksh. dial.) Cum doun t' cam' soid. 1876Mid. Yorksh. Gloss., Cam, a rise of hedge-ground; generally cam-side. ▪ III. cam, n.3 dial. [f. cam a. or v.] Contradiction, crossing in purpose.
1875Lanc. Gloss. (E.D.S.), When he meets wi cam, there's no good to be done. ▪ IV. † cam, a. and adv. Obs. exc. dial. Also kam, (7 kamme). [Adopted from Celtic: in Welsh cam crooked, bent, bowed, awry, wrong, false; Gael. cam crooked, bent, blind of one eye; Manx cam (as in Gaelic); Ir. cam:—OIr. camm crooked, repr. an OCeltic *cambo-s, as in the proper name Cambodunum ‘crooked town’. In English probably from Welsh, and no doubt in oral use long before the 16th c. when first found in literature; the derived form cammed is in the Promptorium.] A. adj. Crooked, twisted, bent from the straight. Hence mod. dial. Perverse, obstinate, ‘cross’.
a1600Hooker Serm. iii. Wks. II. 698 His mind is perverse, kam [ed. 1676 cam], and crooked. 1642Sc. Pasquils (1868) 117 Cam is thy name, Cam are thyne eyies and wayes..Cam are thy lookes, thyne eyies thy ways bewrayes. 1853Akerman Wiltsh. Tales 138 As cam and as obstinate as a mule. 1862Hughes in Macm. Mag. V. 236/2 As cam as a peg. B. adv. Away from the straight line, awry, askew (also fig.). clean cam (kam), ‘crooked, athwart, awry, cross from the purpose’ (J.); cf. kim kam.
1579Tomson Calvin's Serm. Tim. 909/1 We speake in good earnest, and meane not..to say, walk on, behaue your selues manfully: and go cleane kam our selues like Creuises. 1607Shakes. Cor. iii. i. 304, Sicin. This is cleane kamme. Brut. Meerely awry. 1611Cotgr. s.v. Contrefoil, The wrong way, cleane contrarie, quite kamme. 1708Motteux Rabelais v. xxvii, Here they go quite kam, and act clean contrary to others. 1755Johnson, Kam, crooked. ▪ V. cam, v. dial.|kæm| [f. cam a.] trans. and intr. (See quots.)
c1746J. Collier (Tim Bobbin) Tummus & M. Wks. (1862) 53 So ot teh [so that they] camm'd little or none; boh agreed t' pey aw meeon [to pay all between them]. 1847–78Halliwell s.v., A person who treads down the shoe heel is said to cam. North. 1875Lanc. Gloss. (E.D.S.) Colloq. use. He cams his shoon at th' heel. Ibid., Cam, to cross or contradict; to oppose vexatiously; to quarrel. I'll cam him, an' get up his temper. ▪ VI. cam obs. and Sc. form of came, pa. tense of come. ▪ VII. cam obs. f. cham, khan, and var. calm n.2 |