1-27
Figure 1-19A.—Torque differential transmitter.
Figure 1-19B.—Torque differential receiver.
Torque Differential Receiver
The torque differential transmitter (TDX) and the torque differential receiver (TDR) are
ELECTRICALLY IDENTICAL. The only difference in their construction is that the receiver (TDR) has a
damper, which serves the same purposes as the damper in the TR — it prevents the rotor from oscillating.
The real difference in the receiver lies in its application. It provides the mechanical output for a
differential synchro system usually as the sum or difference of two electrical inputs from synchro
transmitters. As in the case with the TDX, the TDR addition or subtraction function depends upon how
the units in the system are connected.
Basically, the torque differential receiver operates like the electromagnets we discussed earlier in this
chapter. In view B, the rotor and stator of the torque differential receiver receive energizing currents from
two torque transmitters. These currents produce two resultant magnetic fields, one in the rotor and the
other in the stator. Each magnetic field assumes an angle corresponding to that of the magnetic field in the
transmitter supplying the signal. It is the interaction of these two resultant magnetic fields that causes the
rotor in the TDR to turn.
