| 释义 |
tachometer|tæˈkɒmɪtə(r)|
[f. Gr. τάχος speed + -meter: cf. barometer.]
1. a. An instrument by which the velocity of machines is measured; spec. one that indicates the speed of an engine in r.p.m. b. An instrument for measuring the velocity of a moving body of water, a current-measurer.
1810Donkin in Trans. Soc. Arts XXVIII. 185 An instrument of my invention for indicating the velocity of machines, and which may not improperly be called a Tachometer. 1825J. Nicholson Operat. Mechanic 42 The method of putting the tachometer in motion whenever we wish to examine the velocity of the machine. 1864Webster, Tachometer,..(b.) an instrument for measuring the velocity of running water in rivers, canals, &c. 1875L. D'A. Jackson Hydraulic Man. i. 84 The tachometer of Brünings is the best instrument of this type. 1918Bull. U.S. Naval Consulting Board No. 3. 10 Many new instruments have been devised for aircraft. These include..tachometers, which indicate the engine speed. 1953C. A. Lindbergh Spirit of St. Louis ii. vi. 187 The tachometer needle shows 1825 r.p.m. 1975Drive New Year 88/1 This is an important job performed by the rev⁓counter, or tachometer.
2. Special Comb.: tachometer generator = tacho-generator.
1946Shell Aviation News No. 103. 24/1 The gearbox is of Rolls-Royce design... It is mounted on the bulkhead and provides drives, on the forward side, for the air pump and the generator, and on the rear side for the tachometer generator. 1958W. D. Cockrell Industr. Electronics Handbk. ii. 254 Tachometer generators are used in systems to generate feedback signals in servoloops or used directly with an indicating instrument.
So taˈchometry, the scientific use of a tachometer; the measurement of velocity; also tachoˈmetric a.
1891Cent. Dict., Tachometry. 1931S. R. Roget Dict. Electr. Terms (ed. 2) 341/1 Tachometric electrometer. 1967O. I. Egerd Control Syst. Theory vii. 238 Tachometric feedback. |