| Brunel Torque Limiting Clutches | |
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| Where to Install / Torque Limiter Selection | |
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In most drive systems there are several
alternate locations where the Brunel clutch can be installed (fig.
1). The preferred position is at the driven shaft. This location
places the overload protection clutch at a point in the drive system
where actual load torque can be accurately monitored. Alternate
locations in the drive system as shown in Figure 1 are usually subject
to greater variation in torque loads due to the reduction ratios
within the drive system. The preferred mounting location will provide
better control of the overload release torque thus preventing unnecessary
release at torques below safe operating levels due to system inertia
and starting torque peaks. |
Figure 1 |
Reduction Gearing
When Brunel Torque Limiting Clutches are installed on large ratio reduction
gear boxes care must be taken since it may not be practical to set a torque
limiter mounted on the input shaft low enough to provide the proper torque
protection on the output shaft. The large reduction ratio will also decrease
the accuracy of the output release torque setting if the clutch is located
on the input shaft.
High Inertia Drive Systems
When selecting Torque Limiting Clutches for use in high inertia drive
system, the location of the clutch must be between the high inertia load
(flywheel, large pulley or gear, etc.) and the driven mechanism. Locating
the Brunel overload release clutch in this position will protect the driven
mechanism from the large inertia forces.
| Optional Features |
Single Position Re-engagement
For use where timing of machine is required. Available for Type JA. (Standard
on JC and JB models.)
Light Duty Springs
For systems requiring very low torque levels and greater range of adjustment
sensitivity.
Single Direction Overload Release
For applications where heavy braking is applied. Type JA only.
Dual Level Torque Setting
For heavy overrunning applications which require normal release torque
setting in one direction and a lower torque release setting in the opposite
direction. Type JA only.
Torque Limiter Selection
Types JA, JB, & JC
For release torques up to 48,000 lb in
Decide on manual or automatic reset. Choose a position as near as possible
to the expected overload (see diagram).
Calculate the torque setting required at that position. This can be determined
from the motor power, r.p.m. and gearing ratio to the driven load or from
the maximum permissible torque for drive components such as compressive
stress on keys. It is the weakest component that requires protection.
Make allowance for motor starting torques (generally twice normal running
torque).
Having calculated an approximate setting for the release torque, final
adjustments can be made on site.
Check from tables that shaft, sprocket or pulley, etc. can be accommodated.
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Selection Example |
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Model Type JAF7-0500 |