Ergonomics - Atlas Copco

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Today, the angle nutrunner can be equipped
with various accessories, such as bar code
readers, to reduce the number of items
to be handled by the operator.
tools in intense use, high temperatures have
caused problems in the past. The advent of
modern, high-efficiency motors brought the
solution.
SHoCK reaCtion
The term shock (or torque) reaction describes
what happens to the machine and the hand
gripping the handle during the tightening se-
quence. The operator experiences the motion
of the handle as a shock only if it lasts for
less than 300 ms. If tightening takes more
than 300 ms, the operator will have time to
increase the force on the handle of the tool
and counteract the reaction torque. Thus, he
will not experience a shock reaction.
The magnitude of the shock reaction,
or jerk, depends on the stiffness of the joint
and the spindle speed. Torque as a function
of time gives the impulse that accelerates
(rotates) the machine – the shorter the
impulse, the smaller the resulting shock
reaction in the handle of the tool. With
hard joints and fast clutches, the operator
needs to apply light force only at the trigger
handle and the inertia of the machine will
absorb the shock reaction.
ViBration
The declared vibration value for angle nut-
runners is