Voice coil motor and method for controlling displacement by magnetic spring force

Abstract

The invention discloses a voice coil motor and a method of implementing displacement control by magnetic spring load, especially a micro voice coil motor applicable to high reproducibility displacement control, comprising a magnetic circuit part and a circuit part, where the magnetic circuit part is used to generate a magnetic field and the circuit part comprises at least a coil and at least a magnetic conductor, where the coil is exerted with a current to be able to generate a driving force and supplies the driving force to a closed magnetic circuit of the magnetic field to generate a positive coupling force; besides, the design of the magnetic conductor can provide a magnetic spring load. And it can further comprise a suspended supporting part, characterized in using the positive coupling force to be able to achieve the purpose of prepressing the suspended supporting part to eliminate dip angle and back lash as moving.

Description

technical field [0001] The invention relates to a voice coil motor, a method for making a voice coil motor device have a magnetic spring force, and a method for achieving displacement control by using the magnetic spring force, especially a miniature motor that can be applied to high-reproducibility displacement control voice coil motor. Background technique [0002] A conventional voice coil motor, as shown in FIG. 29 , includes a fixed magnetic circuit component and a movable circuit component. Among them, the magnetic circuit part is composed of an upper yoke 29011, a lower yoke 29012 and a plurality of magnets 29013, 29014 attached to the inner surface of the upper and lower yokes and maintains an air gap 2904 to form a closed magnetic field. The circuit part only consists of a coil 2903 The structure is placed in the above-mentioned air gap 2904, when the coil 2903 is supplied with a current, the current will interact with the magnetic field in the air gap 2904 to gene...

AI Technical Summary

Problems solved by technology

But in fact, if a voice coil motor using an elastic body is used, the multiple shrapnel sub-support arms 3004 should maintain a consistent elastic constant and deformation characteristics, so that the voice coil motor can truly achieve the effect of a parallel connecting rod when it is displaced, and will not be generated with the displacement. Inclination angle, it is really difficult to achieve mass production with high authenticity rate; in addition, the above-mentioned flat shrapnel or four parallel steel wires must have the function of conducting electricity in addition to providing elasticity, so as to supply the connected coil with a current. The connection method is usually It is solder welding, which is more unfavorable for maintaining a consistent elastic constant and deformation characteristics, and the solder spot is welded to the elastic body that is often deformed, and there is a possibility of falling off

[0005] In addition, when the voice coil motor with an elastic body is applied to a portable camera device, because its flat-shaped shrapnel is very thin, it must pass the drop resistance test. However, the gravity generated by the moving part of the motor does not When it is in the same direction as the preset deformation direction of the shrapnel, it will cause some of the shrapnel sub-support arms 3004 to have torsional deformation. In the lighter case, the root of the shrapnel sub-support arm 3004 will be permanently deformed due to excessive stress, and the inclination angle during displacement will deteriorate. In severe cases, it will break and make the positioning function of the voice coil motor invalid. The above shortcomings will reduce the reliability of the drop resistance when the above-mentioned device is used in a portable camera device.

[0006] In addition, these voice coil motors with elastic bodies such as flat shrapnel belong to an ultra-low damping system, and the instantaneous energy generated during displacement will be stored in multiple shrapnel sub-support arms 3004, even when the motor propulsion force is balanced by the shrapnel deformation force and reach the preset displacement, the voice coil motor only stops accelerating but cannot stop moving immediately. It must go through a certain period of vibration to consume the above-mentioned instantaneous energy before it can stabilize. Therefore, it is usually necessary to add damping glue to the support arm 3004 of the shrapnel The root absorbs the instantaneous energy to shorten the vibration time. The addition of damping glue not only increases the production man-hours and material costs, but also the qualitative change of the damping glue over time will affect the ability to provide damping

Images