- Compact and light weight design.
- No elastomeric elements to degrade or overheat.
- Efficient heat dissipation.
- Superior damping and stiffness linearity.
- Independent tuning of damping and stiffness.
The Riverhawk Viscous Rotational Damper (VRD) is a mechanism that transmits continuous torque and protects connected machines by damping alternating torque vibrations. It is designed to fit in the space between separated machinery shafts.
The Riverhawk VRD can be applied two ways. It can be fitted directly between the ends of machinery shafts where it accommodates small misalignments as a quill or it can be mounted between the flexible elements of a flexible coupling forming the spacer portion of the coupling. This approach provides the equipment designer with the advantage of being able to mate the VRD to flex elements of choice while allowing design for damped torsional natural frequencies.
Design and Operation
A quill shaft designed to transmit steady torque is connected to flanges at both ends. These flanges, in turn, are designed to connect with either coupling flex elements or directly to the mating machines. The damping assembly, consisting of two halves, is positioned over the center section of the quill shaft. Torque tubes mount to each end of the quill shaft and extend to the center where they connect to the damping assembly. The damping assembly consists of a housing and a plate. The housing fastens to one torque tube and the plate connects to the other. Between the housing and plate is a viscous fluid.
The quill shaft twists when torque is applied to the VRD. This twisting action causes the housing and plate to rotate relative to one another shearing the viscous fluid and causing a small amount of energy to be absorbed. When an alternating torque is applied, energy is absorbed for each cycle. The greater the alternating torque, the greater the absorption of energy. This action dampens out torsional vibration and protects connected equipment. Dampened energy is converted to heat where it absorbs into the housing and is quickly dissipated into the surrounding air.