In the structure of a complex and precise motor, Brush Holder, in spite of its small structure, plays an indispensable role in ensuring its motor stability, high efficiency and long-period "hidden protector".
First, precise positing to lay a solid and stable foundation
Brush Holder, as a stable and precise "house", acts as a top priority for safeguarding for a motor, fixing its brush at an optimum position for the purpose of ensuring that the brush can tightly and closely contact with its rotating commutator (or slip ring). It is vitally important for such precise positing, because it can efficiently prevent the brush from swaying and deviating in the process of high-speed rotating and sliding of the brush. Once out of control of the constraint of Brush Holder, the contact of the brush will be instable, being prone to happen to runout and sparking to bring about directional failure for the motor and affect overall equipment normal operating.
Second, current conduction to ensure its normal energy
Brush Holder, as an "energy bridge" between its external stationary electric circuit, is a part of rotating component (rotor) of its inner motor constituted with the brush. Through Brush Holder and the brush, the current of external power can be stably transmitted to rotating rotor winding to produce driving torque for the purpose of continuous operating for the motor. Meanwhile, it takes the responsibility for extracting the current generated by the rotor in its generating mode. The above-mentioned process requires Brush Holder with its excellent current conduction and structural strength to ensure its high efficiency and unobstructed transmission for the energy.
Third, pressure control to realize stable reversing
In order to maintain stable contact between the brush and the commutator, the design of inner Brush Holder equips with hold-down gear for the spring. That device can force a constant and appropriate contact pressure to the brush. And, that force should ensure excellent contact and reduce contact resistance to avoid speeding up frictional loss and heating caused by excessive pressure. Thanks to the above-mentioned precise pressure control, stable "mechanical rectification" can be realized between the brush and the commutator. Furthermore, it can constantly change the current direction in the rotor coil to ensure directional constancy of electromagnetic torque, keeping the same directional rotating for the motor.
Four, prolong service life to enhance safety performance
Brush Holder acts as a vital role in prolonging overall service life and enhancing the safety for the motor, efficiently avoiding sparking and arc caused by bad contact and reducing surface erosion of the commutator and electromagnetic interference with its surrounding electronic equipment. In addition, some Brush Holders also take the responsibilities for transmitting electrostatic charge generated by its motor rotor to the ground, preventing the motor insulation from electrostatic charge accumulation. Brush Holder can indirectly protect more expensive rotor and commutator within reasonable range of the motor wear, reducing the motor maintenance costs.
In conclusion, Brush Holder, in spite of its small structure, acts as a core component integrated positing with conducting, controlling and protection functions. In spite its silent operating, it ensure each and every precise current directional change and high efficiently energy transformation. We can say that, without high-quality Brush Holder, its motor will not be a high performance and a longer period of its service life. Therefore, we can regard Brush Holder as a real "hidden protector" for a stable motor.
