free samples- micro motor carbon brush - Produce according to the graph an...

micro motor carbon brush/Carbon brush for power tools

micro motor carbon brush has the following characteristics:
1, from the appearance point of view:

This product chamfer decent, appropriate specifications, structure specifications

the wire cross-section and length, not loose, falling off, broken off side, off angle, clamp and so on.
2, from the use of terms:
(1) The product of high quality graphite, long life and do not wear commutator or slip rings, commutator appears not to scratch, rough, ablation, drawing and so on.
(2) has a good flow properties and set to change, so that spark suppression in the permitted range, and the energy loss is small.
(3) brush runs, but heat, noise, not broken, do not change color brush braid, no ablation.
(4) is running, can the surface of commutator or collector ring quickly form a uniform, moderate and stable oxide film.
Informations for ur reference
Micro-motor carbon brush

Micro-electric motor brush life expectancy shorter than the large-scale electrical machinery, but the use of household appliances is shorter, therefore, a group generally can use the brush a few years in the life of electrical brush need to be replaced during the examples of many .

Material from the brush of a general can select a low friction coefficient and contact voltage drop of larger graphite electric brush, resin binder for the high resistance of natural graphite brush can be used for the poor motor. In addition, more abrasive strong carbon-graphite brush is mainly used mica sudden ultra-small motor.

Series Motor speed easy to adjust, but with a resistor or transformer to adjust the speed of motor at low speed with lower torque. In order to improve the situation, the use of electronic control of motor speed to increase, which is cheap to run for half-wave, brush-for-life than full-wave to the even shorter, so this is a noteworthy problem.

If the increase in design-for-up to the number of films, or select a large brush cover coefficient (for the brush thickness and thickness ratio), then tends to increase brush wear. Brush cover coefficient generally take 1-3 Comparison ideal. mica insulation under the engraved depth of more than 0.5MM. because brush size smaller, so mica thickness thinner than the large motor is much more, which reduces the vibration of brush are favorable. additional experience that the prediction brush life is very difficult, especially in small brush, high-volume production of motor fluctuations in large prediction difficult is one of the reasons.

Carbon brush performance

Commutator:
Unit must be in good condition, with less than .002" out-of-roundness. Bar edge must be chamfered and there should be no burned edges.

Brush Holders:
They must be mechanically sound and permit the brush to slide freely. Brush holder fingers must move freely and if the unit consists of constant pressure springs, these springs must be in good condition. Springs that are difficult to move, have an excessive accumulation of carbon, or are worn, will cause excessive brush wear.

Brush Holder Angles:
The angles should be set to the original manufacturer's specification. Any more than a 2 degree variation in the setting can cause arcing, bar burning, and excessive wear. Brush holders that vary in the angle set to the commutator will cause the unit to be "off neutral".

Brush Holder Spring Tension:
Maintaining the proper spring pressure reduces arcing, brush wear, heating, and commutator wear. Light spring tension can cause threading and definitely will shorten the brush life. As a general rule, we recommend that the brushes be set at 4 psi pressure. To calculate the pressure, measure the width and thickness of the contact face and calculate as follows:

Pressure in Pounds/Brush = (Width x Thickness x 4 psi)

Brush Holder Quartering:
To insure that the best machine electrical neutral can be achieved, the brush holders must be quartered. Quartering is setting the brush holders at equal distance around the commutator. For a 4 pole machine, the spacing will be every 90 degrees. If the quartering is not properly set, you may experience excessive arcing, heating, brush wear, and commutator wear.

Machine Neutral:
To obtain optimum machine performance, the brush must be set at the machine electrical neutral. If the unit is off neutral, you may observe sparking under a no-load condition. Depending upon how far off neutral the machine is set, there may be arcing and bar burning.

Carbon Brushes Description

The Principal Dimensions of a Carbon Brush

Note:

We work to NEMA and ANSI tolerances on the dimensions given to us. Width and thickness dimensions should be established accurately. If in doubt, it should be noted that the internal dimensions of the brush holder should be about .003" greater than the nominal dimensions of the brush.

Flexible length is the length from the top of the longest side of the brush to the center of the terminal hole.

The dimensions of "d" on the double shank terminals may vary with the flexible size, reducing as the flexible size increases and the minimum permissible dimension should be stated.

Terminals:
Please give the size of opening.