Types of Reduction Gear
Types of Reduction Gear :- Reduction gear is an arrangement through which speed can be lowered (minimized) as per the requirement of slower output speed (with same or more required torque). Reduction gear mainly consist of set of gears which is in connection with wheel & their parts. The incoming high speed motion is transmitted through the set of rotating gears. (While in this case motion or torque has been changed). Number of gear to be used in the reduction gear is based on the output speed requirement as per the application. Reduction gear assembly also known as reduction gearbox.
Reduction gear is also used when reduction of high speed steam turbine motion into low RPM range (To be decided by propeller).
Mounting Option of Reduction Gears
- Base mounted
- Shaft mounted
1. Base mounted :- Base mounted reducer gear which have feet for bolting (platform for stability) are the most common types.
2. Shaft mounted :- Shaft mounted reducer gear which having hollow output shaft that slip over the driven shaft.
3. Gearmotor :- A gearmotor combines an enclosed gearset along with a motor. A motorized reducer resembles a gearmotor except that is driven separate by NEMA C FACE motor.
Types of Reduction Gear ( Types of Gear )
There are mainly two types of reduction gear followed by:
- Single reduction gear
- Double reduction gear
1. Single Reduction Gear: ( Types of Gear )
Single reduction gear having arrangement that consist of one pair of gears. Reduction gearbox consist of different ports for propeller & engine shaft respectively to take entry inside of gear assembly. Assembly is also equipped with small gear known as pinion which is driven by incoming shaft of the engine while pinion is used to drive the large gear that is place on the propeller shaft. The speed is to be adjusted by maintaining the ratio of speed reduction to the diameter of pinion & gear proportional. A single gear assembly having a gear the double size of pinion.
2. Double Reduction Gear: ( Types of Gear )
Double reduction gear is used in application that involving high speed specific needs. In this double reduction gear arrangement pinion is directly connected to input shaft (combines with flexible coupling connection). Intermediate gear is connected to first reduction gear. This first reduction gear is connected to pinion which is operating at low speed with help of another shaft. This pinion is connected to reduction gear that is mounted on the propeller/ shaft. This arrangement fascilates that gives speed reduction up to 20:1 .
Selection of Reduction Gears
Reduction gear comes in two class or configuration with different types while these classes are right angle class or parallel shaft type.
Right Angle Class
They are included with worm types equipped with bevel (straight or helical).and for parallel class of gear reducer having configuration of parallel shaft that include spur (internal & external), helical planetary or harmonic gears. It is also found possible in such a way that reduction gear composed of multi stages which occupies or involve one or more types of gear reducer.
Selection of gear reducer between these two classes based on to the space restriction of the application. Worm gear with speed reduction ratio of 20:1 or greater than this are self locking that can be desirable in application basic requirement is that load is on even after turned off the motor while worms gear are less efficient than the other types of gears which requires the large motor to achieve the same output torque.