Gear Ratio

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gear ratio

[′gir ‚rā·shō]

(mechanical engineering)

The ratio of the angular speed of the driving member of a gear train or similar mechanism to that of the driven member; specifically, the number of revolutions made by the engine per revolution of the rear wheels of an automobile.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Gear Ratio

(1) In a gear drive, the ratio of the number of teeth of a pinion to the number of teeth of a gear, u = z₂/z₁.

(2) In a worm gear, the ratio of the number of teeth of a worm wheel to the number of threads of a worm.

(3) In a chain drive, the ratio of the number of teeth of the larger sprocket to the number of teeth of the smaller one.

(4) In a belt drive or nonregulated friction drive, the ratio of the diameter of the larger pulley or roller to the diameter of the smaller.

The gear ratio is also used in the design of multiple reduction gears. In contrast to the transmission ratio, the gear ration is always greater than or equal to 1.

References in periodicals archive ?

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The variation of the first transmission functions [chi]'(s) shows a low influence for various normalized eccentricities [e.sub.S] / [l.sub.1] given in Table 2, constant normalized crank value [l.sub.4] / [l.sub.1] = 0.5 and the gear ratio [rho] = 1 (Fig.

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While baitcasters have gotten more attention, Abu Garcia released the Revo Rocket spinning reel in 2015, with a 7:1 gear ratio. This uptick in gear ratio realizes major increases in line winding speed, expressed in IPT (Inches Per Turn).

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The IWM operates from 0 to 13,726 RPM in the first/second motor speed range based on the first gear ratio of 49-to-1 (for low speed and high torque).

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Likewise, if you have a 5 tooth front sprocket and a 15 tooth rear sprocket, the front sprocket will have to rotate three times in order to rotate the rear sprocket once, and the gear ratio of this arrangement would be 3:1.

Motorbiking: How gears work

Namely, the numbers of PM pole-pairs in the input and output rotors are online changed by properly magnetizing relevant PM pieces, hence changing the gear ratio of the magnetic gear.

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