Information Details
Torque motor
Torque motor is a low speed, high torque motor. Directly drag load operation, the speed directly affected by the control voltage signal, as in the automatic control system actuators.
Torque motor drag load and high-speed servo motor through drag reduction device has many advantages compared to the load: such as fast response, high precision, small fluctuations in torque and speed, long-term stable operation at low speed situations, and mechanical properties regulation characteristics of good linearity, outstanding performance, especially at low speeds, the speed can be as low 0.00017r / min (4 genius revolution), which speed range up to tens of thousands, hundreds of thousands. Especially suitable for high-precision servo system.
Torque motor can be divided into DC torque motor and AC torque motor two categories, it works with the corresponding servo motor is basically the same, but differ in structure and dimensions. In order to obtain a large torque motor torque and lower speed in the same volume and the armature voltage, typically has a substantially flat structure. Its ratio of length to diameter of the armature is generally about 0.2, and the number of motor poles more.
The following figure shows the schematic structure of permanent magnet DC torque motor. The figure, the stator 1 by the permanent magnets embedded in a stator pole, by the external copper ring 2 is fixed. By permeable laminated rotor core laminations together, placed the rotor slot armature winding, wedges made of a copper plate 3, serves as the commutator segments. Brushes installed in the brush holder, the position can be adjusted as needed. 4 sets of rotor directly on the shaft, the shaft and chassis control system according to the requirements formulated.
1— stator；2—Brass ring；3—Wedge and commutator；4—Rotor
After the voltage applied torque motor electromagnetic torque and rotational speed is zero is called stall torque, zero speed running state, said stall state. Torque motor can often use low speed and stall state.
When the stall torque motor for a long time, stable temperature does not exceed the maximum allowable value of output torque stall called continuous stall torque corresponding armature current is continuous stall current. Operating speed is greater than zero, the output torque is less than the stall torque. Torque motor mechanical characteristics in a straight line. In a very short period of time armature current exceeds the continuous stall current without heating the motor burned out, so that the motor output larger stall torque. But the current is too large will make the permanent magnet demagnetization, demagnetization restricted by the maximum stall torque referred to the peak torque, corresponding armature current is called the peak current. These parameters are permanent magnet DC torque motor is given by the technical data.
AC torque motor, the control signal is AC, and works the same as the two-phase AC servo motor. Just more of its poles, was flat shape.