maxon gear - maxon motor - #1

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30 maxon gear Technology – short and to the point May 2010 edition / subject to change maxon gear Technology – short and to the point Gears If mechanical power is required at a high torque and correspondingly reduced speed, a maxon precision gear is recommended. According to the gear ratio the output speed is reduced while the output torque is enhanced. For a more precise determination of the latter, efficiency must be taken into consideration. Spur gearhead The gear consists of one or more stages. One stage represents the pairing of two cogwheels. The first cogwheel (pinion) is mounted directly on the motor shaft. The bearing of the output shaft 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 efficiency Planetary gearhead Planetary gears are particularly suitable for the transfer of high torques. Large gearheads are normally fitted with ball bearings at gearhead output. 1 Output shaft 2 Mounting flange 3 Bearing of the output shaft 4 Axial security 5 Intermediate plate 6 Cogwheel 7 Motor pinion 8 Planetary gearwheel 9 Sun gearwheel = Planet carrier + Internal gear Program – Planetary gearhead – Spur gearhead – Koaxdrive – Micro Harmonic Drive® – Spindle drives – For transferring high torques up to 180 Nm – Reduction ratios of 4 : 1 to 6285 : 1 – External diameter 6 - 81 mm – High performance in a small space – High reduction ratio in a small space – Concentric gear input and output Koaxdrive The quiet “Koaxdrive” combines worm and planetary gearing. In the first stage, a separately mounted worm drives the three offset planetary wheels which then mesh in the specially toothed internal geared wheel. All further stages are designed as a normal planetary gear: – quiet – high reduction ratio in the first stage – other properties as planetary gears Planetary gearhead Spur gearhead Conversion The conversion of speed and torque of the gear output (nB, MB) to the motor shaft (nmot, Mmot) follows the following equations: where: i: reduction: Gearhead efficiency Selection of gears As with motors, speed and torque limits also apply to gearheads. Operating torque must be below gearhead MN,G nominal torque (max. continuous torque). With short-term loads, the intermittent torque of the gear should also be taken into consideration. Note that the nominal torque (continuous torque) of the gear is dependent on the number of stages. Where possible, the input speed of the gear imax should not be exceeded. This limits the maximum possible reduction imax at a given operating speed. The following applies to the selection of the reduction i If the gear is selected, the data conversed to the motor axis (nmot, Mmot) are used to select the motor. The maxon modular system defines the proper motor-gear combinations.