One of the functions of the coupling is to absorb and compensate for the deviation between the shafts through its own deformation. The greater the deflection, the stronger the ability to absorb the deviation; the smaller the deflection, the weaker the ability to absorb the deviation. Generally speaking, this deviation between the shafts is divided into the following three aspects: The connection between the coupling and the peripheral equipment is achieved by inserting the shaft of the equipment into the shaft hole of the coupling. The shaft hole forms of the coupling generally include keyway type, clamping type, clamping + keyway, top screw type, expansion type, etc. The keyway type is the most widely used and is suitable for ordinary motors, ordinary reducers and ordinary transmission shafts. The clamping type is more widely used in servo motors, stepper motors and various synchronous transmission shafts. The shaft and hole fit tightly without any transmission gap. If an additional keyway structure is added, the torque transmission capacity can be enhanced. The top screw type is suitable for occasions with small shaft diameters and small torque transmission, such as micro motors, encoders, etc.

Couplings transmit torque in drive systems. But their role is more than that. The following are the three basic functions of couplings.

Transmitting torque

Power and speed generate torque. Only when torque is transmitted can the machine operate.

Compensating for misalignment

“If the coupling is not mounted in perfect alignment, it must be able to compensate for misalignment between the drive and driven elements,” says Reinhardt Hackenschmidt, Academic Director of Engineering and CAD at the University of Bayreuth. “This can involve parallel, axial, and angular misalignment.”

Providing smooth operation

“With a coupling, I can adjust the system in a highly dynamic way, provide smooth operation, and dampen vibrations,” explains Norbert Telaar, Head of Strategic Product Management at RINGFEDER POWER TRANSMISSION. “The coupling should be able to handle all of this.”