Quickness reducers are mechanical devices that help drive systems maintain optimal speed and torque for the application form. Also called gearboxes and equipment drives, they lower the acceleration of rotation of the input shaft by a specific ratio and raise the power transmitted to the output shaft by the same ratio. Ratio multipliers raise the speed decrease and torque supplied by a rate reducer by a specific ratio and are suitable for parallel setups. Installation bases, torque hands, and flange couplings are accessories used with acceleration reducers. They are generally used in applications where in fact the speed reducer will not be directly mounted on the drive mechanism.
Many gearbox designs allow for the motor to be directly mounted to the reducer. These styles incorporate either extremely specific flanges to permit the electric motor to be directly connected to the reducer or additional adapters with integral couplings. This eliminates the necessity for separate mounting of the engine, but is usually only practical with smaller sized motors.
Integrating Speed Reducers
After selection, another issue is the way the gearbox will be integrated into the machine. Always check the way the gearbox will end up 
being mounted and how it will be linked to the driver and powered load because it can vary from machine to machine.
torque
speed
horsepower
reducer efficiency
service factor
mounting position
connection variable
life required
In some applications the quantity of backlash, transmission error, torsional rigidity, and instant of inertia are also important. The amount of torque needed could very well be the most crucial criteria, as this translates to the quantity of work the rate reducer must perform.
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