Variable frequency vibration method capable of shortening response time and vibration actuator

Abstract

The invention relates to a variable frequency vibration method capable of shortening response time and a vibration actuator. The vibration actuator comprises a hollow shaft, a vibration output interface and an annular stator elastomer, the hollow shaft is sleeved with the annular stator elastomer, the vibration output interface is fixedly arranged at the top of the hollow shaft through screws, thehollow shaft locks the annular stator elastomer in the axial direction, and meanwhile the annular stator elastomer generates pre-pressure to abut against the vibration output interface; a friction material is laid on the contact surface of the annular stator elastomer and the vibration output interface; and partitioned polarized piezoelectric ceramics are laid on the end face, away from the vibration output interface, of the annular stator elastomer. A plastic wear-resistant sleeve is arranged between the stator elastomer and the hollow shaft, and the plastic wear-resistant sleeve is also arranged on the hollow shaft in a sleeving manner. The problem that a traditional motor is slow in response time can be solved, and the response time of the vibration actuator designed based on the vibration method is greatly prolonged.

Description

technical field [0001] The invention relates to a frequency conversion vibration method capable of shortening response time and a vibration actuator, belonging to the field of ring ultrasonic motors. Background technique [0002] Today's handheld smart devices on the market are all dominated by touch screens with large sizes and high proportions. Device manufacturers are gradually eliminating physical buttons. In contrast, the application of virtual buttons and pressure-sensitive buttons is increasing. Compared with physical buttons, virtual buttons have many advantages, such as: easy to program, and the form and position can be set at will, which improves the humanization of system operation; improves the use of equipment. Lifespan, the mechanical structure of the physical buttons will have performance degradation and waterproof and dustproof problems with use, but the virtual buttons have a fatal shortcoming: no hand feeling, because the virtual buttons are all set on the ...

AI Technical Summary

Problems solved by technology

In contrast, the application of virtual buttons and pressure-sensitive buttons is increasing. Compared with physical buttons, virtual buttons have many advantages, such as: easy to program, and the form and position can be set at will, which improves the humanization of system operation; improves the use of equipment. Lifespan, the mechanical structure of the physical buttons will have performance degradation and waterproof and dustproof problems with use, but the virtual buttons have a fatal shortcoming: no hand feeling, because the virtual buttons are all set on the touch screen, so users will have a feeling when using them. If there is no certain visual or auditory feedback, the user cannot be sure whether the button is pressed; so engineers use vibration as the feedback of the virtual button, and today's vibration tactile feedback has achieved a false effect, such as Apple ( The pressure-sensitive touch panel of the latest notebook computer of Apple Inc) and Magic Trackpad 2, an independent touch panel product, are a good example of implementation; traditional touch panels generally adopt a rocker structure, such as figure 1 As shown in 1a, the touch panel is fixed by a hinge mechanism, and the other end is connected to the tactile switch. Pressing the touch panel will trigger the tactile switch, which will produce a "step" pressing feel and the sound of button pressing; Obviously, this structure cannot be pressed down when pressing the top of the touch panel, that is, near the fixed end of 1a in the figure, which greatly reduces the user experience; 1b in the figure shows Apple's pressure-sensitive touch panel Schematic diagram of the structure. The structure is equipped with pressure sensors at the four corners of the touch panel. When the user's pressing force reaches the set threshold, the linear vibration motor fixed under the touch panel will be activated to output a certain waveform of vibration, so as to simulate the pressure. Tactile sensation (this is the vibration-like phenomenon in tactile psychology. In short, it uses a series of modulated vibrations to give the user the illusion of movement displacement on the touch panel)

The advantage of ERM is that the technology is mature, the cost is low, and the excitation frequency range is 90Hz-200Hz, but the disadvantages are also obvious. Due to the working principle of the electromagnetic motor, this vibration motor has a slow acceleration process when it starts, and it also has a slow acceleration process when it stops. A deceleration process is about 100ms-200ms, so its vibration is not crisp, the waveform distortion is high, and the user experience is poor; the second type is the linear vibration motor (LRC), which has only become popular in recent years and has been installed in On various smart devices, LRC is still driven by electromagnetic force, but its performance is much better than that of ERM. The principle is similar to that of electromagnetic linear motors. A spring mechanism is added to provide a reset force for the mover. When a square wave signal is applied to the mover coil At this time, the mover moves back and forth under the joint action of electromagnetic force and spring force, which plays the role of exciting vibration. Its advantages are: the start-stop response time is relatively short, which can reach 30ms; due to the use of springs, the energy consumption is low ; The excitation frequency range is 150-200Hz. The disadvantage is that the excitation of the vibration motor is still reliable due to the electromagnetic force, so it cannot truly achieve a no-delay response, and the ability to form complex waveforms is still limited; the third is to use piezoelectric ceramics to deform directly A vibration actuator that pushes the mass block to vibrate. This vibration actuator does not rely on electromagnetic force, so the mechanical response time is extremely low, which can reach within 5ms, which meets the requirements of real-time feedback. The excitation frequency range is 150Hz-300Hz, but due to Due to structural size and voltage limitations, the vibration intensity generated on small handheld devices is still insufficient

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