What kind of material Carbon Brush wear resistance?
Carbon Brush is also called brush According to the brush production method, divided into two categories: one is colored brushes, that is, metal graphite brush, the other is a black brush. Colored brushes, containing non-ferrous metals, mainly copper powder, silver powder, followed by lead powder, tin powder, lead oxide powder, the balance for the flake graphite powder. How much of the metal powder content depends on the technical requirements of the brush. Most of the brush material is made of graphite, in order to increase the conductivity, there are made of copper-containing graphite, graphite has a good electrical conductivity, soft texture and wear.
A device that transfers energy or signals between a fixed part of a motor or generator or other rotating machine. It is usually made of pure carbon and coagulant. The exterior is usually a square, stuck on a metal bracket, inside There is a spring to press it on the shaft, the motor rotation, the power through the inverter delivery to the coil, because its main component is carbon, called Carbon Brush, it is easy to wear. Should be regularly replaced and clean up the carbon.
In the technical characteristics of the Carbon Brush table there is no commutator or slip ring wear rate value with a break number. A series of causes of commutator wear can be cited: sparking occurs under the brush, the brush is too hard, there is abrasive material in the Carbon Brush, the hardness of the commutator material is low, the harmful chemical action in the surrounding atmosphere, Point and so on.
The last three reasons for these reasons are independent of the Carbon Brush. The method of sparks and their elimination will be discussed later. Very hard Carbon Brush is usually used in the peripheral speed is low, easy to dirty and black commutator; in this case, the Carbon Brush does not cause the commutator has a great wear rate, but there are clear Grinding effect of dirt on the surface of the commutator. Some companies use a special abrasive Carbon Brush that can make the commutator clean at very high peripheral speeds (this work can not be done with a hard carbon crystal brush because it is suitable for very low peripheral speeds. This type of Carbon Brush, the grinding material is a very small particles into the Carbon Brush material, so that the commutator of the wear and tear evenly, and the root is small.
Carbon Brush is a DC motor or winding motor to the rotor conductive device, can only be passed through it to the rotor up, the role of the motor is to change the current direction of the DC motor and AC motor, DC motor is to change the rotor Convert the coil to change the rotor pole. Thereby changing the movement of the motor. Because the Carbon Brush is relatively soft, and wear-resistant, smooth, not easy to play spark. Conductive performance Ye Hao, not easy to oxidation, deterioration, deformation. So it is generally used for conductive contact surface.
Carbon Brush running in three ways are natural running, manual running, the tool running. Carbon Brush friction surface and the friction surface of the rotating parts to be completely, the current transmission will be uniform. If you do not run the work, the motor will run when there are sparks.
New Carbon Brush before use need to do the work of four points:
1, the new Carbon Brush must be used before the grinding (grinding) to ensure that the Carbon Brush and slip ring surface contact up to 80%, Carbon Brush into the brush to ensure that the upper and lower free to move, if the card astringent phenomenon should be The Carbon Brush four sides with sandpaper polished to keep the Carbon Brush and brush the gap between the wall should be between 0.1-0.3 mm, so as not to brush the card in the brush or because of the gap is too large to produce swing. Brush the lower edge of the distance from the slip ring surface should be maintained at about 3mm ~ 4mm mm.
2, at the same time, each brush frame only for 1 to 2 Carbon Brush, and the old and new Carbon Brush models must be consistent.
3, regularly with a DC clamp meter to measure the current sharing of the Carbon Brush evenly.
4, with a spring scale to check the pressure of the Carbon Brush should be uniform and stable, the unit pressure is usually between 1.1kg ~ 2.5kg, the Carbon Brush between the uneven pressure difference of less than 5%。