HSB (High Speed Backstop) clutches are used on cooling tower fan drives to prevent rotation in the opposite direction from the normal driving direction. When the fan drive is off, wind pressure from other fans or ambient breezes can apply suffi cient force to rotate fan blades in the opposite direction. The HSB clutch allows the fan to freely rotate in the desired driving direction while preventing any rotation in the opposite direction.

Type RSCI is a centrifugal lift
off sprag type freewheel with
the inner race rotating. Only
the inner race is designed
for freewheeling. Primarily
designed as a backstop, this
type can be also used as an
overrunning clutch in crawl
drives, where the overrunning
speed is high but the driving
speed is low.

Bibbigard safety element torque limiters incorporate a number of safety element modules of a specific size mounted between two flanges and preset to release at a specified torque value in order to protect the drive system from expensive damage and lost production. They can be used with various types of drive medium many of which are available from Altra Industrial Motion. Bibbigard has been successfully utilized in many different industries where, subject to space availability, the release torque capacity is virtually unlimited.

•	Accurate release torque repeatability
•	Simple fast manual re-engagement
•	Low-cost maintenance
•	Versatile mounting capability

TB Wood’s offers a full line of sheaves and drives to meet your specific application requirements.

•	Conventional V-Belt drives
•	Narrow drives (Ultra-V)
•	Light-duty drives (FHP)
•	Synchronous Plus drives
•	QT Power Chain® synchronous belt drives

Floating shaft couplings are specifically designed for long span applications from 24” to over 300”. Tru-Tube composite tubes (shown) can be specified for spans up to 220” (6 meters). Composite tubes weigh up to 80% less than steel and can eliminate the cost of bearing supports and other structures.

•	Horizontal or vertical applications
•	Custom designed to specification