Question:
Dear MISUMI Engineering Team,
What is the difference in the single and double type? Why is the “Maximum Stroke” so much different between the two types?
Thank you,
Eric
Answer:
Hello Eric,
I assume you are referring to Stroke bushings. Typically our linear bushings are designed with a return mechanism, where balls recirculate back into the system which allows limitless stroke.
The advantage of using double bushings is having more ball bearings (double amount) in contact with shaft. This allows for great improvement of static and dynamic load, drastically increases your moment load ratings and system’s stability.
The construction of a Stroke Bushing is very different.
There is no ball return mechanism. The balls are embedded into a sleeve and they roll on the shaft’s outside diameter and the housing’s inside diameter while the sleeve is suspended between the two, providing solid lubrication to the ball bearing .
So if the shaft is stationary, while moving the housing, the sleeve with bearing balls will also move, but at different (slower) rate in relation to the shaft, but the sleeve’s travel will be limited by surface length of the housing’s Inside Diameter.
Please, see the single and double Stroke Bushings:
Again, by having double amount of ball bearings you will still benefit from better load ratings, but it will limit your stroke. I hope I answered your questions, but feel free to comment below or contact us at engineering@misumiusa.com with any additional questions!
Thank you,
Chris Blaszcyk
Product Development Manager
Standard Mechanical Components Team
