Over the last several years the reliable mechanical solution that a fixed cam indexer provides has been forgotten by some engineers or younger ones don’t even know it exist.
In most rotary index table applications a fixed degree of motion from station to station never needs to be changed; however some will believe they need flexibility. With a fixed cam indexer the implementation time is reduced and the reliability over time cannot be matched with a programmable solution.
Fixed cam indexers are operated by using AC motors, which can be operated with a simple VFD or contactor/motor starters. You do not need servo motors or drives. Positioning is achieved by the mechanical dwell of the internal cam. With a fixed cam indexer there is never a need to “REHOME” or worry about position drifting overtime do to encoder count roll over.
Programmable indexers do have a purpose and it is important to understand when a programmable indexer should be used. Such as:
- When you have a single dial but want to have batch runs of 2 or more parts. A programmable indexers gives you the ability to program multiple movement profiles to provide the ability to run multiple parts in separate batches without having to go through a mechanical dwell.
- When there is a need to rotate a different degree intermittently to have a part inspected or rejected – For example: A customer has a 4 station index table application and the 3rd station is an inspection station, some customers like the ability to be able to index 45 degrees if a part should have to be rejected. This would not happen on every cycle but they need the ability to reject a part prior to being unloaded if it is a bad part.
- When the customer wants an additional axis to their robot. Our RTF and TMF all have the ability to be an additional axis to most major robot brands. An aux axis motor enables the indexer to become an extension to the robot and be able to communicate with it.
You also need to consider when to not overlook the reliability and reduced commissioning time that a fixed indexer can provide for both the system integrator and the end customer.
View our video with Ben Talan to learn more!
