The Eng.-Office IMBUS received an order to develop a testing system for spring bellows. The test system used until then was not able to determine the characteristics of the mechatronic components with the required accuracy.
The bellows generates a force, which is the sum of the spring force and the force of the gas pressure in the bellows (grey).
The challenge consisted in the accuracy of the parameters to be determined:
- Force range 0 - 100 N accuracy 0,0064 N
- Bellows pressure range 0 - 4,5 bar accuracy 0,75 mbar
- Length of bellows range 0 - 100 µm accuracy 5,4 nm
This means the measurement required ranges of 1:6000, 1: 15.625 and 1: 18.520.
The mechanical design of test facility is critical, because in relation to the required accuracy any deformation of the facility must be taken into account. Also with the fixing of the bellows is to ensure, that the conditions for the use of the application match with the testing system.
With the developed test system will it possible to meet the requirements.
The test facility should measure the force depending on the length and pressure, the bellows stiffness and bellows surface. All values can be determined with an uncertainty of approximately 0.5%.