Romax Technology has recently built its first ever test rig to investigate and validate modelling results of a five speed manual gear box. The test rig has been designed and built by a team of Romax Engineers and it is now being used to complete a series of tests on an automotive manual gearbox.
The test rig features a number of components including a double universal joint arrangement used to provide a dynamic torque excitation. The areas that the engineers are particular interested in analysing are linked to a computer and the test results are fed back for the engineers to then interpret. Currently, Romax engineers are investigating gear rattle of a five speed production gearbox and they are also looking at the effects of oil temperature, oil level and shaft speed on the gearbox.
“It is very important to be able to validate our modelling capabilities and by building this test rig we are able to do this,” explained Ashley Crowther, Chief Engineer at Romax Technology. “This is the first time we have built a test rig of our own, although we have been involved in supporting many clients and Universities over the years to build test rigs. This is something that potentially we will be able to look at working with our clients on in the future and expanding the services we currently offer.”
The test rig has been designed so measurements of drag may be made with control of oil temperature and level. The test data is being used to verify calculations for drag. With the drag data and data describing the input excitation the rig allows for validation of simulations of the gear rattle phenomena. Understanding the magnitude of drag on the individual gears and bearings is critically important for predicting the onset of gear rattle in a transmission as well as determining the severity.