A dynamometer for testing 180 motors per hour for vehicle electrohydraulic power assisted steering, uses a non-contact torque transducer from Sensor Technology of Banbury for ensuring complete accuracy of the readings.
The dynamometer forms part of a highly automated test cell that includes conveyors to deliver and remove a steady stream of motors to be tested. A robot manipulator transfers the incoming motors onto the dynamometer and after testing loads them onto the accept or reject exit conveyor.
This level of automation is crucial for maintaining the cycle time, repeatability and validity of the tests.
Normally with a dynamometer the load is applied by a hysteresis brake and there are negligible losses between these two elements. But in order to allow for the throughflow and handling of the motors the cell had to be arranged with the brake and dynamometer further apart than usual.
Connecting them was achieved using a longer than normal shaft and coupling. This introduced parasitic losses into the system, which had to be accounted for if the test results were to be accurate. An elegant solution was achieved by installing a TorqSense transducer to regularly test the torque inherent in system. The test instruments are then calibrated to account for the measured offset .
One of the key reasons for selecting TorqSense transducers for the test rig was that they do not need to be physically connected to the test piece via a complicated set of slip rings which would be time consuming to assemble and dismantle between each motor under and made the required 20 second turnaround unachievable.
The dynamometer forms part of a highly automated test cell that includes conveyors to deliver and remove a steady stream of motors to be tested. A robot manipulator transfers the incoming motors onto the dynamometer and after testing loads them onto the accept or reject exit conveyor.
This level of automation is crucial for maintaining the cycle time, repeatability and validity of the tests.
Normally with a dynamometer the load is applied by a hysteresis brake and there are negligible losses between these two elements. But in order to allow for the throughflow and handling of the motors the cell had to be arranged with the brake and dynamometer further apart than usual.
Connecting them was achieved using a longer than normal shaft and coupling. This introduced parasitic losses into the system, which had to be accounted for if the test results were to be accurate. An elegant solution was achieved by installing a TorqSense transducer to regularly test the torque inherent in system. The test instruments are then calibrated to account for the measured offset .
One of the key reasons for selecting TorqSense transducers for the test rig was that they do not need to be physically connected to the test piece via a complicated set of slip rings which would be time consuming to assemble and dismantle between each motor under and made the required 20 second turnaround unachievable.
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