Why brushes sparkle in a vacuum cleaner
A small spark between brushes and a collector is normal. It is quite another thing if the first straight "erupt" sparks. Increased arcing of the brushes in the electric motor of the vacuum cleaner indicates a malfunction that can significantly reduce the life of the device. The phenomenon may be accompanied by loss of engine power, uneven operation, overheating and other malfunctions. About why the vacuum cleaner brushes spark, and what can be done, we will tell in this publication.
The simplest and most obvious cause of sparks is the wear of brushes. Despite the fact that collector motors are equipped with special sparking capacitors, which, in addition to the function of increasing the service life of these elements, also reduce radio interference, the brushes are erased over time and must be replaced.
Brushes - the element of the electric motor, providing contact between the fixed and movable electrodes.
To replace the brushes, you first need to get to the electric motor. For this it is necessary disassemble the vacuum cleaner. In most cases, using a screwdriver is quite simple, but do not forget to unplug the device. Having examined the vacuum cleaner and providing convenient access to the engine, we find the brush holders. Depending on the design, to remove the brushes from the brush holder, you usually need to pull the latches, for this you may need a screwdriver.
In recent years, many manufacturers supply their vacuum cleaners with a set of spare brushes. But if you had to buy the device without additional parts, then they can be purchased in stores where they sell power tools.
When buying new brushes you need to pay attention to their size and material.
Brushes are graphite and copper-graphite. It will be better if you remove the old elements from the electric motor of your vacuum cleaner in advance and go to the store with them, so as not to make a wrong choice.
In most cases, the brushes will spark when there is poor contact with the collector. This happens if you install new ones. For a more snug fit of the brushes to the collector, you can use the "skin" zero, or just let the vacuum cleaner run at medium speed for about 20 minutes. Sure to check bearing condition, since their wear can cause beats and uneven rotation of the rotor. Similarly, the protrusions of the insulation between the collector plates, scratches on the surface, various irregularities manifest themselves. For polishing using abrasive paper.
Brushes should not hang out in the brush holder, but have a free wheeling, which is provided by a spring, the state of which also plays an important role.
If you decide to replace the brushes, be sure to pay attention to how tightly the spring presses them against the manifold. Sometimes, in order for the brushes to press more strongly, it is enough to slightly stretch the spring.
With the wrong angle of inclination of the brushes relative to the stator, sparking is also possible.The correct position is when both brushes are strictly on the same line passing through the axis of rotation of the collector. Over time, due to constant vibration, the attachment of the brush holder can loosen or even get mechanical damage. Carefully inspect the surface of the nodes. Parts that are cracked, chipped, or corroded should be replaced.
Each manufacturer contributes design features to its product line, and therefore different types of vacuum cleaners have a different type of mounting brushes. However, in general, all models have the same device, and the brush holder is usually bolted with two screws and allows adjustment.
The collector surface at the point of contact with the brushes must be clean. Coal or metal dust resulting from rubbing brushes against rings or a collector can have a detrimental effect on contact. Pollution of the latter causes sparking, from which carbon is formed. Self repair vacuum cleaner in this case involves the usual cleaning. If the surface has traces of pollution, it is necessary to get rid of them with the help of a small skin, and then degrease by rubbing with alcohol or gasoline.You should also pay attention to the space between the contacts on the rotor. If they are clogged with dirt or graphite dust, they should also be cleaned and degreased.
The most unpleasant thing that can happen with the motor of a vacuum cleaner is an interturn short circuit in a winding. As a rule, arcing in this case occurs in a circle, engine speed drops, claps are possible, collector plates have significant blackening. In this situation, you face whole motor replacementbecause the cost of the armature can be 70-80% of the cost of the entire electric motor, and to rewind in living conditions is not an easy task.
The main malfunctions that can lead to sparking in a vacuum cleaner are the following:
- various mechanical damage, scratches;
- carbon on the surface of the cage;
- defects in soldering and poor contact of elements;
- ring skew;
- cracks in the traverse;
- wear and deformation of the contacting elements;
- wear or breakage of the spring.
Worn brush holders are subject to repair or replace. Electric motor elements such as brushes should be provided with regular maintenance, which consists in observing the contact surface,maintaining its purity and the required nominal area of contact with the collector or rings.
In addition, care must be taken to ensure that the pressure on the rotor is uniform, because otherwise the wear of the brushes is uneven. Over time, the brushes wear out and must be replaced in time to prevent sparking, which can lead to the formation of soot and other more serious damage to the electric motor.