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Common Causes Of Power Tools Carbon Brush Failure Causes

Sep 20, 2017

Common causes of Power Tools Carbon Brush failure causes
What is the motor Power Tools Carbon Brush? Those who have not come into contact with this industry really will not know. The Power Tools Carbon Brush is a conductive member which is in sliding contact with the moving member to form an electrical connection. The Power Tools Carbon Brush is used as a sliding contact body for introducing and exporting current on a commutator or slip ring. Do not look at it very small, but it is also a very critical part, if it fails is very troublesome. Let's take a look at the causes of the failure of the carbon brush in the power tool.
1, electromagnetic factors
Reactive or excitation current adjustment, the Power Tools Carbon Brush spark has changed significantly. When the exciter is switched, the Power Tools Carbon Brush is in poor contact with the commutator and the contact resistance is too large. Commutator or slip ring oxide film thickness is not uniform, causing the Power Tools Carbon Brush current distribution is not balanced. Or sudden changes in load, as well as sudden short circuit lead to commutation between the voltage distribution anomalies; unit overload and imbalance. Power Tools Carbon Brush selection is unreasonable, electric tools, such as carbon brush spacing; power tools, such as carbon brush quality problems.
2, mechanical factors
Commutator center is not correct, the rotor is not balanced, the unit vibration, for the film between the insulation protruding or rewinding protruding, Power Tools Carbon Brush contact surface grinding is not smooth, or commutator surface rough and poor contact To the surface of the device is not clean, the exchange of different air gap from the pole, the Power Tools Carbon Brush on the spring pressure is not uniform or size is not appropriate, the Power Tools Carbon Brush in the brush grip too loose and beating, or too tight power tools The carbon brush stuck in the brush. Unit operating speed is reduced or vibration is improved and sparks will be reduced.
3, chemical factors
The unit is running in a corrosive gas, or the unit operating space lacks oxygen, the commutator and the Power Tools Carbon Brush contact with the surface of a layer of natural formation of copper oxide film is destroyed, the already formed, similar to the linear resistance The commutation is no longer present, and the commutator sparks are exacerbated during the re-formation of the oxide film on the contact surface. The commutator (or slip ring) is corroded by acid gas or grease.
Power Tools Carbon Brush appears in the following circumstances should be replaced: 1, serious wear and tear (less than the original length of 1/3); 2, serious damage; 3, electric tools, carbon brush and slip ring contact surface less than 70%.
Replacement method of Power Tools Carbon Brush:
1, hand holding the Power Tools Carbon Brush handle counterclockwise rotation 90 degrees, out out, remove the brush grip, electric tools, carbon brush and spring;
2, hold the spring, the Power Tools Carbon Brush out, with a screwdriver loose brush braid fixed bolts, the old electric tools to remove the carbon brush;
3, will be used to dry the sandpaper sandpaper finished electric brush carbon brush in the brush, with a screwdriver fastening brush braid fixed bolts;
4, gently pull the brush braids, check the Power Tools Carbon Brush is free in the brush grip activities, and check whether the spring pressure can be Power Tools Carbon Brush back;
5, hand holding the Power Tools Carbon Brush handle, the brush will be aligned on the convergence ring on the card slot slowly brush grip complex, and then hand clockwise direction handle 90 degrees;
6, check the Power Tools Carbon Brush and slip ring contact is good.
The Power Tools Carbon Brush can shorten the manufacturing cycle and greatly reduce the production cost. Due to the need for any special equipment, especially for the field processing large carbon steel elbow. The blank is flat or can be curved surface, so the material is simple, easy to guarantee, easy assembly and welding.
Power Tools Carbon Brush for welding when the note:
1, in order to prevent the Power Tools Carbon Brush because of heating and produce eye erosion, welding current should not be too much, less than about 20% of carbon steel electrode, arc should not be too long, cold between the layers, narrow bead is appropriate.
2, the power tool after the hard brushing brush harder, easy to crack. If the same type of Power Tools Carbon Brush welding, must be more than 300 ℃ preheating and 700 ℃ after the slow cooling treatment. If the weldment can not be heat treated after welding. You should use the Power Tools Carbon Brush electrode.
Power tools Carbon brushes have a certain degree of corrosion resistance (oxidizing acid, organic acid, cavitation), heat and abrasion resistance. Usually applicable to the oil, natural gas, chemical, hydropower, construction and boiler industries such as pipeline system.