How to adjust the position of the brushes of the DC motor

At present, most of the DC motors sold on the market rely on the battery to power the direct current.

To distinguish between DC motor and AC motor, look directly at the structure, the structure of AC motor should be simple, especially the brush. Series motors are AC, but there are also brushes. The brushless DC motor is a permanent magnet with a controller and works directly with AC power.

The brushes of the DC motor are generally placed on the physical center line.

The carbon brush is generally made of pure carbon plus coagulant, and the appearance is generally a square, stuck on the metal support, and there is a spring inside to press it tightly on the rotating shaft, such as after the completion of oil drilling, it needs to be detected, and the instrument must be put down from the wellbore, which is to send the signal from the rotating part to the surface instrument through the carbon brush. The carbon brush looks a bit like an eraser strip for wiping a pencil, with a wire leading out on top. The volume is large and small.

As a sliding contact, carbon brushes are widely used in many electrical equipment.

Our factory is specialized in the production of brushed DC motors, and it happened that before coming to this unit, I had done brushless DC motors for half a year. I'm from the design department, and I've only been here for a short time, so I'll tell you about it.

At present, a large part of DC motors are powered by batteries, that is, direct current.

To distinguish between DC motor and AC motor, just look at the structure, the structure of AC motor is much simpler, especially the brush. In fact, the series motor is AC, but there are also brushes, which can only be seen in terms of specific products, and cannot be explained clearly in one or two sentences.

The brushless DC motor is a permanent magnet (I used to do this) with a controller and works directly with AC.

The reversible rotating DC motor motor is generally on the geometric neutral line, and the brushes of the DC generator or the DC motor rotating in one direction should also be placed on the geometric neutral line in principle, but sometimes in order to adjust some characteristics of the motor, the brush position is allowed to offset some positions around the geometric neutral line, but the distance of the offset is not large.

In short, the last correct position of the brush should be the spark level on the commutator, the speed regulation of the motor and the voltage regulation of the speed tolerance of the generator are all within the specified range.

Precautions for DC motor brushes.

It should be noted that when choosing a brush, you should pay attention to the size of the brush and the hardness of the brush. The thickness of the brushes should not be too wide or too narrow. The width (thickness) of the brushes used by large and medium-sized DC motors is generally 2 3 pieces of commutator thickness.

The width of the brushes used in small DC motors should generally be the thickness of 1 commutator piece.

The brushes selected should be moderately soft and hard. The brush is too hard, will make the commutator wear and tear seriously, and will soon make the brush surface form a smooth hard surface, so that the contact resistance between the brush and the commutator increases, and affects the normal conductivity and work of the motor. If the brushes are too hard, it will also make a loud noise when the motor rotates.

The brush selection is too soft, the brush wears out too fast, and the motor works for a period of time, which will make the brush and the commutator surface contact poor.

The position of the brushes of the DC motor is generally placed on the physical center line (that is, the position where the magnetic flux density is equal to zero), so that the induced potential in the winding short-circuited by it can be zero, so that the spark can be smaller when the coil is commutated;

Problem 1: DC brush motor speed regulation The easiest way is to add your AC220--DC250 to the contact AC voltage regulator

Problem 2: How to achieve speed regulation with a 12V DC motor Use NE555 to control the duty cycle.

Question 3: How to control the speed of DC brush motor It is best to have a detailed and clear circuit diagram and description Small permanent magnet motors, usually can use PWM to regulate the speed, using MOS tubes or IGBTs to form H-bridge circuits, search for H-bridge circuits There are many answers, by changing its on-time.

Question 4: How to use resistance to regulate the speed of 36 volt brushed DC motor It is unreasonable to directly regulate the speed with series resistance, and you can use the adjustment of the base bias resistance of the high-power triode to make the motor connected in series on its collector get different currents to change the speed.

Question orange slip five: what is the reason why the 48v DC brush motor does not have speed regulation Hello:

1. The brush motor of the electric vehicle is out of control (driving at full speed, not slow), which should be the manifestation of the power triode breakdown in the controller: uncontrolled.

2. If the power triode of the controller breaks down, the battery voltage will be added to the motor at full voltage, so there is a phenomenon of loss of control. You should check and replace the power tube of the controller.

Question 6: What are the speed regulation methods of DC speed regulating motor There are three basic speed regulation methods for DC motors. They are: string resistance speed regulation, step-down speed regulation, and weak magnetic field speed regulation.

Question 7: How to use resistance to regulate the speed of the DC motor, I want to be in detail, whether it can be in detail is to use the DC motor in series with the resistance, and change the resistance value of the resistance will also change the current in the circuit, so as to achieve the purpose of speed regulation, the DC motor uses the resistance to regulate the speed is the simplest speed regulation circuit.

The current reduction is to reduce the output of the electric power pin plex to regulate the speed and reduce the voltage.

Now there is no need for resistor speed regulation, and the thyristor is used for stepless speed regulation or frequency conversion speed regulation.

For low-power DC motors, a variable resistor is connected in series in the power supply circuit to realize the speed regulation function. Of course, the power of the variable resistor should be large enough.

Problem 8: DC'Brushed motors'with'Brushless motor'Can the speed and switch be more accurate and sensitive through PWM? Is there a difference in the control effect?

I can't find anything with a brush.

Question 9: What are the methods of speed regulation for micro DC motors? The speed regulation method of DC motor is to adjust the armature voltage, and the second is to adjust the excitation current, and the common micro DC motor, its magnetic field is fixed, non-adjustable permanent magnet, so it has to adjust the armature voltage, to say that there are several ways to adjust the armature voltage, the commonly used one is the thyristor voltage regulation method, and then the pulse width modulation method (PWM).

Question 10: My motor is a brushed DC motor, the power supply is a 48V battery, if you want to regulate the speed of what kind of governor should be used, the governor should be 48V1500-2000 watt brush motor governor.

The position of the brushes of the DC motor is generally placed on the physical center line (that is, the position where the magnetic flux density is equal to zero), so that the induced potential in the winding short-circuited by it can be zero, so that the spark can be smaller when the coil is commutated;