The major function of a drill motor is to covert the electrical energy into the mechanical energy. The drill motors are quite effective to carry out even tedious jobs like drilling and driving. However, the problem in the market place is that, there are too many options for the drills. To start with, it is to be said that there are two major categories, one is Brushed motor and the other is Brushless. Both of the motors are equally effective and efficient. However, there are some structural, operation and control differences between the two types of motors.
Brushless Motors Vs Brushed Motor:
Before we discuss about different motors, first we need to understand the basic difference between the two types of motors. There is an elementary difference and that is the variants used to make the motors. The Brushed motors are made up of carbon, while the brushless motors are made up of magnets. The magnets are used for generating power for brushless. However, for brushed motor, it is the carbon material generates power.
When generally compared, Brushless Motors are considered edge ahead thanks to the functionality of the motors. The brushless motors are next generation motors and does not really generate any friction while generating the power. The lack of friction simply means that the heating is very less and that of course enhances the durability of the motor as well. When it comes to the maintenance, Brushless Motors again nose ahead of the Brushed motor. There aren’t any worn brushes in the brushless motor, thus when dusting comes, there isn’t any need of replacement of the brushes.
The commutation of the brushless motor windings isn’t mechanical, interestingly, it is driven by electric power, administrated by the controller. The controller has the ability to transform the DC current and turns it into three phase variable frequency. This frequency basically supplies the motor coils the energy to create the rotating field. How is it different than Brushed Motor? Well, the motor coil does not really rotate.
As far as the design is considered, the brushless motors generally have same compact design. The brushless motor comes with a Fixed Stator. This stator works to hold the motor coils. The permanent magnets are coupled with these rotors and that generate the magnetic field. It depends on the manufacturer to decide the build of the rotors. It can be star sized or it can be a triangle as well. The internal rotor of the brushless motor can generate up to 100,000 rpm even.
The number of poles used in the motor drill is completely dependent on the desire of the tool. It is true that if you want more torque in your motor, then you can always use for Motor Poles. However, that in turn reduces the maximum speed and that is something uncalled for. Also, the material used has an impact on the flux density. Keeping all such things in view, an optimal combination is achieved for maximum torque and speed.
There are different algorithms that are used for the Brushless Motors. The most common are Trapezoidal Commutation, Sinusoidal Commutation and Vector Control. The algorithms have different impact of software and hardware changes we implement in the motor. For example, a Trapezoidal brushless motor has very simple circuit and a good control. This is an ideal motor for the small tools. The other algorithms are complex in nature but of course provide better efficiency and control.
Having said all the good things about the Brushless Motors, does not really take away anything from the Brushed motors. The Brushed motors are around the corner since long and have served the purpose very well. It is efficient and powerful as well. However, the mechanism of the motor drill is different than Brushless. It may be said that Brushless is modern, but Brushed isn’t outdated either. The brushed motors are used in many types of tools such as Jackhammers, planers, hedge trimmers and grinders as well. The major component of this motor is however Carbon.
The carbon brushes can differ according to the tools. However, the brushes are installed on the motionless part of the motor. This is done to ensure a smooth and optimal transmission of power to the rotor of the motor. Now, this rotor of brushed motor rotates unlike the Brushless motors.
The carbon brushes are generally put along with the slip rings. The slip rings are made up of graphite, however, the shape might vary according to the tool used. There isn’t a structure for the brushed motor. The slip ring can be combined with a spring to support the carbon brushes; on the other hand, it can be a simple wire connecter. The carbon brushes also come with the different sizes. Interestingly, grooves are used in the brushes. The major reason behind it is the improved guidance system.
Now, the big question is how the power generates and how the speed is determined. The torque or the speed of the drill is determined by the magnetic field produced in the brushed motors. The carbon brushes that are connected ensure that the power is given a clear passage and that enhances the performances. Unlike the brushless motors, there are breaker brushes in this kind of motor as well. These are used to stop of the operation of the drill before the wearing out of the graphite.
These brushed motors are used in many tools as mentioned before and are capable of producing adequate power. The sizes of the carbon brushes are generally small, but the magnetic field created in the motor is quite high for operational efficiency. you will easily find the best cordless drills operates on brushless Motor.
Advantages of Brushless Motor:
There are several advantages that Brushless Motor enjoys and thus stays ahead in the race with Brushed Motor.
The power of the tool is increased with Brushless motors along with the life expectancy. The life of the brushless motors depends on the bearings and thus it enhances the durability.
The size of the Motor is smaller than the Brushed Motors and thus it fits in quite easily in tools. This also ensures that the portability of the tool is improved.
The light weight of the motor ensures that the portable tool is also light in weight.
This motor uses the electronic commutations with different algorithms. This again makes this motor quite fascinating as it can preciously position the target. The efficiency also increases optimal balanced rotors.
Of course, there is no friction between the rotor and the stator and that resolves the very problem of the overheating and loss of energy. The battery life also gets increases by 25% thanks to less friction. No spark is also seen during the operation as there is no friction.
Disadvantages of Brushed Motor:
The Brushed Motors are very inexpensive. If closely followed, then it can be understood that the motors are capable of generating high torque and very powerful. The brushed motor is reliable but that does not make it a perfect motor to look for. There are few drawbacks that these motors have and that are quite daunting for the impression of the brushed motor.
These motors are manufactured with carbon brushes. These can result in wear and tear and the maintenance cost can often increase.
As there is friction in this type of motor, overheating is a common problem.
The battery efficiency is quite poor for these motors. The overall battery drain due to the overheating is a major concern for this motor type.
Brushless Motors are costlier than Brushed Motors:
Brushless Motors are obviously costlier than the brushed motors. There are different reasons behind it. The brushless motors are electronic controlled motors where it offers more power, flexibility, control and efficiency than the brushed motors. The maintenance cost of the brushless motor is also less than brushed motor with higher durability. All of these qualities of the Brushless Motors make sure it costs extra than the brushed counterparts.
The Brushless Motors also work on DC current. Hence, when you connect it to the AC current, it gets split into 3 variable frequency thanks to the electronic card installed in it. The electronic module constantly regulates the current in order to ensure the optimum operating efficiency of the rotors and maximum output.
In conclusion, it can be easily said, that the Brushless motors are better than the Brushed motors. These are better controlled and way more efficient than the brushed motors. Even though, the brushless motors are costlier than the brushed ones, but the less maintenance cost easily compensates that fact.
Even though there are some tools that still use the Brushed Motors, but Brushless Motors are mostly found in today’s competitive market.