| 释义 |
▪ I. servo, n.|ˈsɜːvəʊ|
[The first element of servo-motor (and servo-mechanism) used substantively.]
1. a. A servo-mechanism or servo-motor.
1910Engineering 14 Jan. 56/2 A patent ‘Servo’ regulator valve is fitted in the dome [of the boiler]. 1924Motor 7 Oct. 448/3 The servo actually trebles the braking effect usually obtainable for a given pedal pressure. 1948I. A. Greenwood in I. A. Greenwood et al. Electronic Instruments viii. 220 A convenient classification of servos may be made in accordance with their uses, the principal examples of which are ‘position servos’ and ‘velocity servos’. 1959Times 1 Sept. 12/2 The..company have now introduced a vacuum-hydraulic brake servo which can be fitted easily to cars and light motor vehicles and is claimed to make a vast improvement in braking. 1966Electronics 17 Oct. 108 To test a servo that controls a radar antenna, the antenna must be moved. 1971Sci. Amer. July 120/3 The first truly automatic servo..was the fantail, a small windwheel mounted at right angles to the main sails and geared to turn the entire top of the windmill. 1976B. Jackson Flameout (1977) iv. 28, I put electronic sensors on the wing tips and tail to respond to phugoid oscillations and dampen yaw. The control servos respond to the input from the sensors.
b. transf. = servo-mechanism b.
1953P. A. Merton in G. E. W. Wolstenholme Spinal Cord (Ciba Foundation Symp.) 249 The stretch reflex servo, which is so obviously concerned with maintaining length and not tension, must necessarily have receptors which record length. 1969Proc. Roy. Soc. B. CLXXIII. 156 Voluntary movement could be initiated by the α route without sacrificing the advantages of a servo.
2. attrib. and Comb., as servo actuation, servo-actuator, servo assistance, servo loop; servo-actuated, servo-assisted, servo-driven, servo-operated adjs.; servo-ˈamplifier, the part of a servo-mechanism that responds to the small error signal and delivers a corresponding large signal to drive the servo-motor; servo brake, (a) a vehicle brake whose application is assisted by the momentum of the vehicle; (b) a brake that is operated by a servo-mechanism; hence servo-braking vbl. n.; servo flap Aeronaut. = servo tab below; servohyˈdraulic a., both servo-controlled and hydraulic; servo-ˈmultiplier, a device for separately multiplying each of several voltages by a single voltage, the former being applied to a set of potentiometers on the same shaft as a potentiometer controlled by a servomotor receiving the latter voltage; servo system = servo-mechanism a; also transf.; servo tab Aeronaut., a tab, operated directly by the pilot, which gives rise to aerodynamic forces that assist in moving the main flap.
1961Hovering Craft & Hydrofoil Oct. 18/2 The ultimate *servo-actuated mechanical device may take ten years.
1959K. Henney Radio Engin. Handbk. (ed. 5) xxv. 9 Deviations of the airplane about the yaw axis result in rotation of the heading stator with respect to the rotor and a signal to the rudder servoamplifier, causing *servo-actuation of the rudder surface and the servo loop action described above.
1970Times 4 Sept. (Aviation Suppl.) p. iv/4 Savings will also accrue from the replacement of the common mechanically coupled control systems in the aircraft by electronic systems with electro-hydraulic *servo-actuators operating various aircraft control surfaces.
1946Radar: Summary Rep. & Harp Project (U.S. Nat. Defense Res. Comm., Div. 14) 143/2 *Servo-amplifier, the amplifier of power impulses in a servo system. 1947Electronic Engin. July 215/1 In a characteristic arrangement, a valve circuit, known as the ‘servo amplifier’, controls the rotation of an electric motor. 1959K. Henney Radio Engin. Handbk. (ed. 5) xxv. 8 The signal from the servoamplifier is applied to the elevator servo⁓motor which actuates and drives the elevator surface. 1966McGraw-Hill Encycl. Sci. & Technol. XII. 199/2 The servoamplifier is often electronic but may be a magnetic amplifier, a relay type of amplifier, or any combination of these types.
1929Times 2 Nov. 4/7 A pedal applies the rearmost Euro [brakes] with vacuum *servo assistance. 1972Guardian 28 Jan. 3/4 (Advt.), To stop, there's a dual circuit four-disc system with servo assistance.
1951Automobile Engineer May 199/1 (heading) *Servo-assisted hydraulic brakes. 1976Field 18 Nov. 1021 (Advt.), All four alloy wheels enjoy servo-assisted disc brakes.
1924A. W. Judge et al. Mod. Motor Cars II. vii. 118 The Hispano-Suiza *servo-brake controls are shown in perspective arrangement. 1926Encycl. Brit. II. 980/2 This led to the development of so-called servo brakes, in which the momentum of the car was utilised to reinforce the effort of the driver in applying the brake. 1951Automobile Engineer Feb. 60/1 (heading) Duo servo brakes.
1924Motor 28 Oct. 707/1 We are now able..to give the first complete description of the *servo-braking system adopted.
1947Proc. IRE XXXV. 450/2 It is possible to divide one voltage by another using a *servodriven potentiometer. 1966M. Woodhouse Tree Frog xxi. 153 One small directional dish [antenna] which..I guessed was servo-driven.
1929Rep. & Mem. Aeronaut. Res. Comm. No. 1262. 2 The control column is attached directly to the *servo flap by means of wires. 1935Aircraft Engin. VII. 303/1 During the past year or so there has been a growing tendency towards the use of small servo flaps on elevators and rudders either for trimming or for balancing.
1972Physics Bull. Aug. 492/2 Fulmer Research Institute has recently installed a Mand *servohydraulic testing facility to meet the increasing demand for testing larger specimens under widely varying rates of loading. 1980Jrnl. R. Soc. Arts May 319/2 Facilities include a {pstlg}350,000 Schenk servo hydraulic rig for testing structural fabrications to destruction.
1946Radar: Summary Rep. & Harp Project (U.S. Nat. Defense Res. Comm., Div. 14) 143/2 *Servo loop, that collection of elements in a servomechanism which measures the error in the quantity to be controlled and applies a correction tending to reduce that error to zero. 1953P. A. Merton in G. E. W. Wolstenholme Spinal Cord (Ciba Foundation Symp.) 247 The stretch reflex is a feedback or servo loop, the feedback being negative. 1978R. Jansson News Caper 10 Even with all the damping in the servo loops the controls leaped out of my hands... We flopped around the sky.
1952G. A. & T. M. Korn Electronic Analog Computers vi. 245 In the case of *servomultipliers, probably the best solution..is to make sure that the follow-up and multiplying potentiometers are all loaded by equal resistances. 1965A. W. Langill Automatic Control Systems Engin. II. xviii. 503 Although the servomultiplier is normally employed to form the product of two analog voltages, the system is also used extensively in the generation of arbitrary functions.
1928Rep. & Mem. Aeronaut. Res. Comm. No. 1171. 9 (heading) Theory for aerofoil R.A.F. 28 with *servo operated flap. 1947Proc. IRE XXXV. 444/1 Servo-operated torque amplifier.
1946Radar: Summary Rep. & Harp Project (U.S. Nat. Defense Res. Comm., Div. 14) 143/2 *Servo system, a mechanical, frequently electromechanical, system for transmitting accurate mechanical position from one point to another by electrical or other means. The position is corrected by feeding back an error signal. 1947Electronic Engin. July 215/2 All quantities may be converted to a consistent electrical basis by employing a servo system. 1964Language XL. 219 The fact that some sort of neurological servosystem does monitor encoding cannot be doubted. 1971Engineering Apr. 45/2 A servo-system can be used to restore the balance after change of displacement.
1939F. K. Teichmann Airplane Design Man. xiii. 207 If the tab can be controlled from the cockpit, it may be used to operate the larger surface and is then called a control-tab or a *servo-tab. 1975L. J. Clancy Aerodynamics xvi. 551 Another related device is the so-called servo-tab, which is designed to provide all the hinge movement required to deflect the control.
Hence as v. trans., to control or operate by a servo-mechanism; ˈservoed ppl. a.
1971New Scientist 12 Aug. 359/2 Ferguson solved this problem with their ingenious double-sided vacuum servo, which servos the brakes on and servos them (and the driver's foot) off. 1978Nature 20 Apr. 704/2 The mapping operation was achieved by driving the telescope in declination at the maximum servoed rate of 130′ min—1 back and forth across the galactic plane.
▪ II. servo, n.2 Austral. colloq.
Brit. |ˈsəːvəʊ|, U.S. |ˈsərvoʊ|, Austral. |ˈsɜvoʊ|
[‹ serv- (in service station n. at service n.1 Compounds 38) + -o suffix.]
A service station.
1985Brisbane Tel. 20 Aug. 5 The servo would have gone up [in flames], taking with it the adjoining house. 1994J. Birmingham He died with Felafel in his Hand (1997) vi. 135 We went into a Shell servo to get some change. 2004Sydney Morning Herald (Nexis) 13 Mar. 26 Gleeson was the servo attendant and McHugh the telegram boy. |