Numerous industrial machines need energy at slow speeds and higher torque. Conveyors and concrete mixers are typcial examples of machinery with such specifications. At speeds of 780 rpm and much less, the following drives might be prudently utilized: chain drive, belt drive, separate speed reducer coupled towards the motor, or gear motor.
The gear reducer motor is really a speed-reducing motor that provides a direct energy drive from a single unit. The gear motor offers an very compact, effective, packaged energy drive. A gear motor generally consists of a standdard AC or DC motor along with a sealed gear train properly engineered for the load. This assembly is mounted on a single base as a 1 package, enclosed pwoer drive. The benefit of this unit is its intense compactness. A gear motor really is smaller sized than a low-speed regular motor from the exact same horsepower.
The motor-shaft pinion of the worm gear motor drives the gear or series of gears in an oil bath that is linked with the output shaft. This type of arrangement is usually the most economical and convenient way to obtain low speeds of approximately 1 rpm to 780 rpm.
One-unit gear motors are available with the following options:(1)shafts parallet to each other or at right angls, (2) polyphase, single-phase, or DC voltages, and (3) horsepower ratings ranging from approximately 1/6 hp to 200 hp.
Gear motor are accessible in numerous from the regular motor kinds like squirrel cage or wound rotor induction motors, operating at either continuous or adjustable speeds. The manage gear for the motor is chosen exactly the same as for any other motor from the exact same kind.
When choosing a gear motor, an essential consideration will be the degree of gear service and gear life primarily based around the load circumstances to which the motor will probably be subjected. Gear motors are divided into 3 classes. Every class utilizes various gear sizes to deal with particular load circumstances. Every class give concerning the exact same life for the gears. The American Gear Manufactures’s Assocation has defined 3 operationg conditons generally discovered in industrial service and has established 3 regular gear classifications to meet these circumstances.
Class I: For steady loads within the motor rating of 8 hours per day duration, or for intermittent operation under moderate shock conditions.
Class II: For 24-hour operation at steady loads within the motor rating, or 8-hour operation under moderate shock conditions.
Class III: For 24-hour operation under moderate shock conditions, or 8-hour operation under heavy shock conditions.
For conditions that are more severe than those covered by Class III gears, a fluid drive unit may be incorporated in the assembly to cushion the shock to an acceptable value.
To achieve multiple speeds, separate units are available with a transmission comparable to that of an automobile. These units must be assembled with the motor and the driven machine. Because the amount of power lost in gearing is very small, the multiple drive has essentially constant horsepower. In other words, as the output speed is decreased, the torque is increased. Generally, this means that larger shaft sizes are needed for the output side.