Twiflex Link Clutch

The Link Clutch Coupling comprises seperate driving and driven members - completely disconnected when at rest.

The driven member is in the form of a drum and the driving member a hub to which lined shoes are connected via pairs of links and rubber bushes. The rubber bushes can be set to control the speed at which the shoes commence to engage, provide frictionless non-wearing pivots and also deflect to accommodate misalignment thereby enabling the clutch to 'double' as an efficient flexible coupling.

Link Clutch Specification

Link clutches are supplied with spring restraint when uncoupled engine idling is needed, and in most cases will provide sufficient torsional flexibility and damping.

When additional flexibility and damping is required we recommend the use of our FlexiClutch design.

Operation

The clutch is normally selected to operate with 'leading shoes' having a stable servo action - 'trailing shoe' selections (which often means a larger size) are used to provide more liner area to cater for high inertia drives with a long slip period on starting. Rotation of the driving motor causes the shoes to move outwards by centrifugal action and engage the drum resulting in a smooth take up of drive as speed of the driver increases.

No slip takes place at the operating speed which means a 100% effecient form of power transmission.

Special Features

Twiflex link clutches can be used as a simple, effective, speed limiting brake to launch lifeboats or restrain the fall of elevators or automatic doors.

Special features for engine and electric motor drives:

• Load free starting prolongs life of motor switch gear and reduces starting currents, aids engine starting in cold weather.
• Peak torques can be utilised to accelerate heavy inertia machinery, permitting use of smaller, less costly squirrel cage motors or less powerful engines, especially where speed increasing drives are involved.
• Misalignment can be accommodated, blind assembly is possible and installation is simplified.
• Overload protection prevents engine stalling, motor overheating, limits vibratory torques and stresses due to sudden jams.
• Engaging speed can be above engine idling speed to permit automatic throttle control.
• Complete disconnection when stationary. Dual or stand-by drives can be engaged or disengaged automatically.
• Motors and engines cannot be driven in reverse by machines such as large centrifugal pumps stopping with a full discharge head of water.
• Flange type hubs facilitate direct mounting to engine flywheels to provide compact installation with minimum axial space.