| The rapid progress of technology has made people pay more and more attention to the improvement of the quality of life.The functions of smart devices such as mobile phones are becoming more and more complete.The demand for using mobile phones as entertainment devices is increasing.The requirements for tactile feedback experience are becoming more and more stringent.Vibration motor is the carrier of tactile feedback,so it puts forward higher requirements on the performance of vibration motor,rich vibration modes,faster response speed and ideal vibration intensity,etc.The traditional eccentric rotating mass motor(ERM)has a long start-up time and high power consumption due to its large starting inertial mass,and the vibration intensity is determined by the motor speed.It is difficult to produce a rich sense of vibration and is gradually eliminated.The most commonly used vibration motor on the existing mobile phone is the linear vibration motor(LRA).The resonance mechanism of the linear vibration motor makes it only work in a narrow frequency range.The vibration generated by the linear vibration motor is very single and requires a long distance to increase the inertial force.Therefore,the volume is generally not small.Due to the advantages of piezoelectric drive in speed and frequency,as well as high control accuracy and large driving force,piezoelectric haptic vibration technology has no restrictions on the frequency of use.Researchers can design vibration modes that cannot be achieved by linear motors and rotor motors.Produce more vibration effects,so the application in this area is very promising.This paper proposes a structure applied to mobile phone vibration motor,which can show excellent performance in response frequency range,vibration intensity and response speed.The research content mainly includes the following aspects:1.By consulting a large number of relevant literatures on mobile phone vibration motors,analyzing the functional requirements of existing smart electronic devices for vibration motors and the shortcomings of traditional vibration motors,combining the advantages of piezoelectric drives,a magnetically acting piezoelectric vibrator is proposed.Structure,to explore the performance of the structure as a vibrator of a vibration motor in terms of vibration performance.2.A detailed introduction to the piezoelectric vibrator of the power source of the vibration motor,including the application fields of different types of piezoelectric ceramics,the microscopic mechanism of the piezoelectric effect,etc.,according to the working principle of the vibration motor to select the parameters of the piezoelectric ceramics,and determine the piezoelectricity The support mode of the vibrator is a cantilever.Based on the piezoelectric equation and the knowledge of material mechanics,the output relational expression of the bimorph piezoelectric cantilever is derived,and the influencing factors of the output performance of the piezoelectric cantilever as a motor vibrator are obtained.3.Combining the size and functional requirements of the mobile phone vibration motor,the structure model of the permanent magnet stiffness nonlinear vibration motor is established.Based on the theoretical model of the magnetic dipole force,the potential energy relationship between the two magnets is derived,and the magnetic force in the vibration direction is obtained.Equivalent force,the expression of the nonlinear restoring force of the piezoelectric vibrator is given,and from the perspective of the potential energy of the system,the steady-state situation of the system at different magnet spacings and the relationship between the stiffness of the vibrator and the magnet spacing are obtained,which is the power of the motor vibrator Prepare for the establishment of learning equations.4.Use MATLAB to perform numerical simulation analysis on the dynamic model of the vibration motor-driven mobile phone,explore the vibration characteristics in the frequency domain and time domain with different magnet spacing,and study the nonlinear vibration characteristics from the aspects of vibration intensity,bandwidth and response speed.The vibration performance of the vibration motor is affected.5.Design an experimental platform with adjustable magnet spacing in solidworks,use precision engraving machines and wire-cutting machine tools to manufacture the designed experimental platform,design an experimental program to verify the correctness of the simulation results,and discover the application of the structure proposed in this article through experimental research Because the vibration motor can effectively strengthen the vibration intensity,the broadband output performance is superior,and the response speed is improved to a certain extent.6.Summarize the factors that are not considered in this article as a structure applied to the vibration motor of mobile phones,and propose possible improvements. |
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