maxon

maxon gearTechnology – short and to the pointmaxon gearGearsIf mechanical power is required at a high torqueand correspondingly reduced speed, a maxonprecision gear is recommended. Accordingto the gear ratio the output speed is reducedwhile the output torque is enhanced. For a moreprecise determination of the latter, efficiencymust be taken into consideration.ConversionThe conversion of speed and torque of the gearoutput (n L , M L ) to the motor shaft (n mot , M mot ) followsthe following equations:Program– Planetary gearhead– Spur gearhead– Koaxdrive– Spindle drives1 Output shaft2 Mounting flange3 Bearing of the output shaft4 Axial security5 Intermediate plate6 Cogwheel7 Motor pinion8 Planetary gearwheel9 Sun gearwheel= Planet carrier+ Internal gearn mot = i · n LM LM mot= i · i · ɳwhere:i: reductionh: Gearhead efficiencyService lifeThe gears usually achieve 1000 to 3000operating hours in continuous operation at themaximum permissible load and recommendedinput speed. Service life is significantly extendedif these limits are not pushed.If the speed drops below this threshold, thegearhead may be loaded with higher torqueswithout compromising the life span. On the otherhand, higher speeds and thus higher reductionratios can be chosen if the torque limits are notfully exploited.Factors affecting life span include:– Exceeding maximum torque can lead toexcessive wear.– Local temperature peaks in the area of toothcontact can destroy the lubricant.– Massively exceeding the gear input speedreduces the service life.– Radial and axial loads on the bearing.Selection of gearsFor the selection of the gearhead, the maximumtransmittable power – the product of speed andtorque – is decisive. It should be noted that thetransmittable power depends on the number ofgear stages.The load torque should be below the nominaltorque (max. continuous torque) of the gearheadM N,G .M N,G ≥ M LFor short-term loading, the short-term torque ofthe gearhead must also be considered.Where possible, the input speed of the gear i maxshould not be exceeded. This limits the maximumpossible reduction i max at a given operatingspeed. The following applies to the selection ofthe reduction ii ≤ i max=n max,GnLSpur gearheadThe gear consists of one or more stages. Onestage represents the pairing of two cogwheels.The first cogwheel (pinion) is mounted directlyon the motor shaft. The bearing of the outputshaft is usually made of sintered material.– Favorably priced– For low torques– Output torque up to 2 Nm– Reduction ratios of 6:1 to 5752:1– External - Ø12 - 45 mm– Low noise level– High efficiencyTemperature/lubricationmaxon gears are lubricated for life. The lubricantsused are especially effective in the recommendedtemperature range. At higher or loweroperating temperatures we offer recommendationsfor special lubricants.If the gear is selected, the data conversed tothe motor axis (n mot , M mot ) are used to select themotor. The maxon modular system defines theproper motor-gear combinations.30Technology – short and to the pointMay 2012 edition / subject to change