12 Jul How many vibration motors are there in your mobile phone?
Mobile phone has become a necessity of modern people’s life, Call, video, mobile office are inseparable from it. There is a function in the mobile phone that can’t be seen but can’t be lost. This is the vibration function. It enables people to receive information calmly in quiet occasions. Why do cell phones vibrate? It’s because there’s a vibration motor in the phone.
·Vibration motor and its working principle
The motor uses the electric coil to drive the rotor to rotate under the action of electromagnetic force in the magnetic field, so as to convert the electric energy into mechanical energy.
·Mobile phone vibration motor
There is at least one small motor in all mobile phones. When the mobile phone is set to the silent state, the incoming call information pulse is converted into the driving current, and the motor rotates under the excitation of the current.
When an eccentric block is installed at the shaft end of the motor rotor, eccentric force or exciting force will be generated when it rotates, which will drive the mobile phone to vibrate periodically and prompt the operator to answer the phone, so as to achieve the prompt function of not affecting others.
The vibration motor in the old mobile phone is actually a kind of micro DC motor, the power supply voltage is about 3-4.5v, and the control method is no different from the ordinary motor.
·Smart phone motors and types
The most primitive mobile phone has only one vibration motor. With the upgrading and Intelligent of mobile phone application functions, the enhancement of functions such as taking pictures, photographing and printing has become an important technical means for various brands of mobile phones to seize the market. Nowadays, smart phones should have at least two motors. At present, there are mainly traditional vibration motor, linear vibration motor and voice coil motor.
·Traditional vibration motor
The micro DC motor with polarizer is the traditional vibration motor for mobile phone, namely ERM motor or eccentric rotor motor. ERM is the abbreviation of eccentric rotating mass.
·Linear vibration motor
Different from the rotary motion polarization motor, the motion mode of linear vibration motor is reciprocating linear motion. In structure and principle, the traditional rotary motor is developed into a straight line along the axis, and the rotary motion is converted into a linear motion. Linear vibration motor is also called linear resonant actuator LRA, where LRA is the abbreviation of linear resonant actuator.
·Voice coil motor
Because of the same working principle as loudspeaker, it is called voice coil motor or VCM motor.
·Features and applications of various mobile phone motors
·ERM motor and LRA motor
ERM motor with eccentric rotor, can produce all-round extreme tremor experience, low cost, long application history. Compared with ERM motor, LRA motor has obvious advantages in two aspects
A.The power consumption is very low, and the vibration combination mode and speed can be more diverse and free.
B.The vibration is more elegant and refreshing.
Auto focus function is required for mobile phone photography. In the traditional way, the focusing function will greatly increase the size of the circuit board and the thickness of the mobile phone. The VCM auto focusing motor occupies a small area of the circuit board, has high reliability and supports high power, which is the best choice for the mobile phone camera module.
In addition, VCM motor also has the following features:
The lens can be stretched and retracted by means of reed, which can realize smooth and continuous lens movement.
It can cooperate with all lenses, and the mobile phone / module of the manufacturer can be selected flexibly.