The allowable moment of a single-axis actuator represents the load capability of the built-in linear guide, and there are the 2 types indicated below, the allowable static moment and the allowable dynamic moment.
The allowable static moment is an index for damage and is the maximum moment that can be applied to a single-axis actuator at rest.
This index is calculated based on the condition where an indentation is made on the track of the built-in linear guide (basic rated static load) and the durability of used parts. If a moment greater than this value acts on the actuator, movement defects and damages can occur. Since our allowable static moment also takes into account the durability of the parts, it cannot be compared to a moment that is calculated only based on the basic rated static load (static rated moment). The durability of the parts is inspected by testing and analyzing them, so the product can be used safely if the allowable value is not exceeded.
However, please avoid excessive vibrations and impacts to the product.
The allowable dynamic moment is an index for service life and is the value through which our standard rated life of a single-axis actuator is calculated. Our company has set the standard rated life of a ROBO Cylinder as 5,000 km and the standard rated life of a single-axis robot as 10,000 km (excludes some models).
This index is calculated based on the condition where the track of the built-in linear guide flakes due to wear (basic rated dynamic load). If a moment greater than this value acts on the actuator, service life can become less than the standard value.
Since our allowable dynamic moment also takes into account the decrease in life due to operating conditions (standard load coefficient), it cannot be compared to a moment that is calculated only based on the basic rated dynamic load (dynamic rated moment). Under normal usage environment, the life can be calculated with a simple formula. There are 3 directions, Ma (pitching), Mb (yawing), Mc (rolling), on which moments act on a single-axis actuator, and allowable moments are calculated for each direction.