Will the stepping motor lose its magnetism when it is disassembled?
Will the stepping motor lose its magnetism when it is disassembled? In principle, the commonly used stepping motor is divided into two types: reactive stepping motor and Hybrid Stepping Motor. Reactive stepping motor can be disassembled, and Hybrid Stepping Motor must not be disassembled, it is a tragedy when it is dismantled. The lighter is folded in half, and the heavier is completely decorated.
Mainly mixed use of strong magnetic aluminum nickel cobalt material, this material is high temperature resistant, high temperature does not demagnetize, it is filled to saturation state during production, if disassembled, the magnetic circuit is no longer closed, the magnetic core will weaken, and special magnetizing equipment is needed. Ordinary people cannot solve it. If NdFeB Material is used, it is not a big problem to disassemble it. Permanent magnet Hybrid Stepping Motor (Common 1. 8 degrees, 0. 72 degrees)The rotor cannot be taken out, otherwise it will be demagnetized. Unless you have a magnetizing machine to re-magnetize.
I have heard a saying before that when repairing the mechanical watch head, the magnet should be short-circuited with a soft iron after it is taken out, so that the magnetic field will not be lost, but the operation of the stepping motor is still a bit troublesome, after all, it is more precise.
If you must remove it, prepare the magnetic'Short Circuit'Tools are fine.
In the same way, when the pointer multimeter is removed, the magnetic circuit is disassembled to cause the magnetic density to drop, and the sensitivity of the meter head will drop, resulting in a very large error, which is also magnetic. 'Short Circuit'The method of disassembly.
When the magnetic circuit must be disassembled, it should be'Magnetic short circuit'
That is, the soft iron material is placed on the two magnetic poles of the magnet, so that the magnetic flux passes through the soft iron material without lowering, and the magnetic gap can be disassembled.
When it is installed back, the magnetic gap is also installed first, and then removed. 'Magnetic short circuit'. However, sometimes'Magnetic short circuit'
It is very difficult, for stepping motors,'Magnetic short circuit'
The inner diameter of the tool used must be equal to the inner diameter of the motor stator, allowing only a few errors. It is difficult to process the tool even on a lathe.
The current permanent magnet Hybrid Stepping Motor is small in size, large in power, small in magnetic gap, only a few wires, and needs to prepare a magnet. 'Short Circuit'
Device to plug in the magnetic gap, such as preparing a stator with the same inner diameter (With the rotor can have a gap loose fit)Iron cylinder.
Not thin-walled of the iron cylinder wall thickness at least 8 ~ 10mm.
It is not to insert the ultra-thin iron cylinder into the gap, but to lean the cylinder end against the stator so that the cylinder and the stator are roughly concentric, and then move the rotor from the stator to the iron cylinder along the axial direction.
A motor with a printed rotor was once dismantled, and a magnetizing coil was wound on the internal magnetic steel.
Even demagnetization, if the motor itself has a large torque margin, it does not affect the use.
However, the error is obviously too large when the multimeter measures accurately.
All components using permanent magnetic materials, such as speakers, pointer multimeters, permanent magnet motors. . . . . .
Unless you have to, don't open the magnetic circuit, otherwise'Magnetic weakening', Cannot be restored.
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