I. Definition
As the name suggests, the motor rotor is the part of the motor that rotates inside the motor and is an important component of the motor
Structure
The rotor generally consists of rotor core, shaft, commutator and other components, non-brushless motor rotor with carbon brushes, and part of the fan, play a role in heat dissipation.
Material
Rotor core; generally by the 0.5mm thickness of silicon steel sheet punching stacked composition, periphery has many grooves for placing the rotor winding, as part of the motor magnetic circuit, silicon steel sheet insulation between each other.
Rotor winding: squirrel cage and wire-wound two kinds of
1, squirrel cage type is generally aluminum bars
2、Wire-wound type is generally pure copper wire
Rotor shaft: generally made of medium carbon steel or alloy steel
Four, type
According to the rotation mode is divided into internal rotor rotation and external rotor rotation.
Internal rotor rotation: the core in the middle of the motor as a rotating body, output torque (refers to the motor) or income energy (refers to the generator).
Outer rotor rotation: the outer body of the motor is the rotating body.
V. Principle of rotation
The rotor winding is driven by the rotating magnetic field generated by the stator energized to produce electromagnetic torque and thus rotate.
Sixth, the common fault
1, excessive wear and tear or poorly assembled bearings, resulting in stator and rotor friction, so that the surface of the iron core damage, resulting in a short-circuit silicon steel sheet
Methods: Remove burrs with fine runt and other tools to eliminate the silicon steel short, clean and coated with insulating varnish, and heat drying.
2、Moisture and other causes of iron core surface corrosion
Method: Use sandpaper to polish clean, clean up and apply insulating paint.
3、Dismantle the old winding with too much force, so that the inverted groove is skewed outward.
Method: Use small mouth pliers, wooden hammer and other tools to be trimmed, so that the groove reset, and in the bad reset gap between the silicon steel sheet to join the green shell paper, glue board and other hard insulating materials.
4, because of the winding grounded to produce high heat burned iron core or tooth part
Methods: with a chisel or scraper and other tools to remove the fused deposits clean, coated with insulation Giverny drying.
5, the core and the seat of the combination of loose
Methods: the original positioning screws can be tightened, if the positioning screws fail, can be re-drilled and tapped positioning holes in the seat, tighten the positioning screws.
6、Broken rotor
Methods: After confirming the rotor conductor material, the broken conductor top replacement and the original conductor material size and other consistent conductor, need to ensure close contact with the rotor can not be loose.
7、Shaft diameter wear
Reason: the inner ring of the bearing and the shaft diameter of the interference is too small, the shaft and the inner ring relative movement occurs in operation, resulting in shaft diameter wear.
Methods: plating, welding processing, set, etc., set is generally used in the shaft diameter wear larger or localized burn damage blue annealing.
8, iron core loose
Reason: rotor core and shaft loosening, high speed noise, serious motor will not turn. The rotor shaft out, hold the rotor with one hand, hold the shaft with one hand, twist, such as can turn is that the core is loose.
Method: Replace a shaft of the same type.
9、Rotor shaft broken or cracked
Methods: broken or cracked size affects the motor operation, need to press out the old shaft to replace the same type of shaft, if it is a large rotor, when the rotor shaft transverse cracks do not exceed 15% of the journal, longitudinal cracks do not exceed 10% of the circumference, can be used to repair the shaft cracks, car leveling can continue to use.
10、Rotor shaft bending
Reason: incorrect installation, long-term overload or external collision caused by the stator and rotor rubbing, resulting in friction and mechanical noise.
Methods: rotor shaft bending amount of more than 0.2mm using a press or lathe to fix the rotor shaft through the lever principle of pressure correction, such as no more than, then use the press or knocking method of correction.
11, rotor shaft bearing overheating
Reason: the bearing assembly is too tight or too much or too little bearing lubricant.
Methods: Bearing problem reassembly bearing, lubricant problem replacement and clean lubricant and re-add the specified capacity.
