That could apply to an Indexing Table that has a set number of fixed positions and these positions are controlled by a cam that is turned by a cotinuous running motor. To get the Table to dwell longer at a station they use Double Dwell.??????
Dwell - is a pause in motion - for example when you reach a depth with a drill you wait for a short period of time before retracting or continue with the next plunge.
double dwell - may then be a longer dwell or two distinct dwells at different depths.
Rotary motion is like a shaft or around a pivot.
intermittent - is like at random otherwise it would be regular.
An electric or electronic fault could be intermittent.
the rotation of a shaft could also be intermittent. and dwell before it changes direction.
Maybe you should state the type of machine you are enquiring about.
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