Cog-Buster - for Smooth Slip Torque
|A major improvement in hysteresis brakes (U.S. Patent # 5,238,095) makes slip torque smooth under virtually all operating conditions|
Hysteresis brakes from other manufacturers cog. Cogging is pulsating output torque. The brake tries to lock into preferred positions - about 12 to 25 positions per revolution, depending on the number of primary poles.
Cogging occurs continuously after the input current is decreased substantially, while the shaft was stopped or moving quite slowly. For example, while setting up for a tensioning application, if the operator even momentarily adjusts the input current higher than needed, and then lowers the current, the brake will cog, and continue to cog at the lower torque setting, until manually decogged.
To manually de-cog:
1) Increase input current (and torque) to the highest value previously used.
2) Turn the shaft while simultaneously decreasing the input current to zero.
That's not very convenient, especially if the brake is in a remote location within your machine. If the machine operator is not trained or aware about cogging, your critical application could be run with pulsating torque. The cogging could yield false test data or sub-standard or ruined end product.
To decog a brake with the Cog-Buster feature, simply turn the shaft one turn. That's it. Within one revolution, cogging is gone, regardless of the chosen torque.
With a Placid Industries hysteresis brake, your web handling, torque testing, load simulation or any application will run smoother and better.