An elastic coupling is a mechanical device designed to connect two rotating shafts, transmitting torque while accommodating misalignments (axial, radial, or angular) and absorbing shocks, vibrations, or sudden load fluctuations. Its key feature lies in the elastic element (e.g., rubber, polyurethane, or metal springs) that provides flexibility, distinguishing it from rigid couplings which lack such cushioning.
Torque Transmission: Efficiently transfers rotational force between shafts, ensuring power flow in machinery like motors, pumps, conveyors, or industrial gearboxes.
Misalignment Compensation: Compensates for minor shaft misalignments (common in installation or due to operational wear), reducing stress on bearings and other components.
Vibration Damping: The elastic element absorbs vibrations and dampens shocks, protecting sensitive machinery from damage and reducing noise.
Overload Protection: In some designs, the elastic material acts as a "fuse"—it deforms or fails under extreme overload, preventing damage to primary equipment.
Hubs: Two metal hubs (often made of steel or cast iron) that attach to the driven and driving shafts via keys, splines, or clamping mechanisms.
Elastic Element: The flexible core, typically made of:
Rubber/Polyurethane: Offers excellent vibration damping and cost-effectiveness; ideal for low to medium torque applications (e.g., household appliances, light machinery).
Metal Springs (e.g., disc springs, coil springs): Suitable for high-temperature, high-torque scenarios (e.g., automotive engines, heavy industrial machinery) due to their durability and heat resistance.
Spacer/Flange: Connects the hubs to the elastic element, ensuring even force distribution.
Based on the elastic element and design, common variants include:
Jaw Couplings: Use a rubber or polyurethane spider (elastic insert) between two jaw-shaped hubs; simple, compact, and widely used in light-duty applications.
Tire Couplings: Feature a rubber "tire" (elastic sleeve) bonded to metal flanges; excel at damping vibrations and handling large misalignments.
Disc Couplings: Utilize thin metal discs (elastic by flexure) for high torque and precision, suitable for high-speed machinery (e.g., turbines).
Grid Couplings: Employ a metal grid (spring) as the elastic element, balancing flexibility with high torque capacity (common in heavy industry).
Elastic couplings are ubiquitous across industries:
Automotive: Used in drive shafts, connecting engines to transmissions to dampen vibrations.
Industrial Machinery: Pumps, compressors, and conveyors rely on them to handle misalignments and protect motor bearings.
Marine Engineering: Connect ship engines to propeller shafts, withstanding axial movements from hull flexing.
Renewable Energy: Wind turbines use elastic couplings to link generators to gearboxes, absorbing dynamic loads from wind fluctuations.
