21 May 2024

Plotting torque against shaft position

Simultaneous readings of torque and rotary position, allows full optimisation of drive operations

Sensor Technology has announced it has launched a new encoder option, the SGR523, for use with its range of precision torque sensors.

The company says the new option represents a significant improvement of the existing SGR511/521 60 line encoder and SGR 512/522 360 line encoder options already available. By combining and comparing the readouts from these two instruments, it becomes possible to plot instantaneous torque values against the angle of a shaft.

Typically, the need is to measure peaks and troughs in torque against the instantaneous angle of the shaft, or to build a complete model of a driven system’s performance against a baseline of time or shaft rotation. Such information could then be used to optimise the operation of pumps and fans, tools such as screws and drills, systems such as cap tighteners and motion mechanisms, and even the driving characteristics of electric vehicles.

The SGR523 encoder is of incremental format, rather than absolute. if absolute shaft position is required, an optional index home pulse can be connected to the angle zero input of the transducer. This will reset the angle encoder back to zero once per rotation.

In use the encoder’s in-phase and quadrature-phase signals are read by the torque sensor and combined with its own output signals to produce a pulse-RPM signal which will have a resolution of twice the encoder pulses. Optionally the in-phase and quadrature-phase encoder signals can also be read and recorded, to enable tracking of rotational direction information.

The maximum operational speed of the combined TorqSense/encoder unit depends on the encoder resolution: a 2048 pulses per revolution encoder can operate at a maximum speed of 9000 RPM, while a 10,000 pulses per revolution encoder can operate at a maximum speed of 1500 RPM.

Company info: Sensor Technology