Audio Enhancements In Devices Using Motors

Abstract

A motor may include a coil assembly, a ring, one or more magnets, and a shaft. The coil assembly may include one or more coils arranged in a circular structure. The ring may surround an outer surface of the coil assembly. One or more magnets may be adhered to an inner surface of the ring. The one or more magnets may correspond with a respective coil of the one or more coils. The shaft may extend through a center portion of the circular structure. The shaft may provide a rotational axis for the motor. The shaft may be configured to generate a natural resonance that does not overlap with an operating frequency of the motor.

1 . A motor comprising:
 a coil assembly that includes a plurality of coils arranged in a circular structure;   a ring surrounding an outer surface of the coil assembly;   a plurality of magnets adhered to an inner surface of the ring;   a lower cage comprising an inner ring and an outer ring connected via a plurality of radial arms; and   a shaft that extends through a center portion of the circular structure and provides a rotational axis for the motor, wherein the shaft has a natural resonance that does not overlap with a mechanical vibrational frequency of the motor.   
     
     
         2 . The motor of  claim 1 , wherein the shaft comprises a metal composition including steel, stainless steel, titanium, beryllium copper, or beryllium. 
     
     
         3 . The motor of  claim 1 , wherein the shaft is a hollow construction. 
     
     
         4 . The motor of  claim 1 , wherein the shaft has a first diameter and a second diameter. 
     
     
         5 . The motor of  claim 4 , wherein the first diameter is about 1 mm to about 4 mm, and the second diameter is about 3 mm to about 7 mm. 
     
     
         6 . The motor of  claim 1 , further comprising:
 a plurality of bearings having a center portion through which the shaft extends,   wherein the center portion of each of the plurality of bearings is in contact with the shaft, and   wherein the lower cage is in contact with an outer portion of each of the plurality of bearings.   
     
     
         7 . The motor of  claim 6 , wherein a bottom portion of the lower cage comprises a plurality of radial arms, wherein each of the plurality of radial arms includes a bolt through hole. 
     
     
         8 . The motor of  claim 7 , further comprising:
 a plurality of dampeners adhered to each of the plurality of radial arms such that each of the plurality of dampeners form a ring around each of the bolt through holes.   
     
     
         9 . A motor comprising:
 a coil assembly that includes a plurality of coils arranged in a circular structure;   a ring surrounding an outer surface of the coil assembly;   a plurality of magnets adhered to an inner surface of the ring;   a lower cage comprising an inner ring and an outer ring connected via a plurality of radial arms; and   a shaft that has a wall thickness configured to reduce noise caused by a torsion mode of the shaft.   
     
     
         10 . The motor of  claim 9 , wherein the shaft has a natural resonance that does not overlap with a mechanical vibrational frequency of the motor to reduce noise caused by the torsion mode of the shaft. 
     
     
         11 . The motor of  claim 9 , wherein the shaft comprises a metal composition including steel, stainless steel, titanium, beryllium copper, or beryllium. 
     
     
         12 . The motor of  claim 9 , wherein a first portion of the shaft a hollow construction and a second portion of the shaft has a solid construction. 
     
     
         13 . The motor of  claim 12 , wherein the wall thickness is about 2 mm to about 4 mm. 
     
     
         14 . The motor of  claim 13 , wherein the shaft has a diameter of about 10 mm to about 15 mm. 
     
     
         15 . The motor of  claim 9 , further comprising:
 a plurality of bearings having a center portion through which the shaft extends,   wherein the center portion of each of the plurality of bearings is in contact with the shaft, and   wherein the lower cage is in contact with an outer portion of each of the plurality of bearings.   
     
     
         16 . The motor of  claim 15 , wherein a bottom portion of the lower cage comprises a plurality of radial arms, wherein each of the plurality of radial arms includes a bolt through hole. 
     
     
         17 . The motor of  claim 16 , further comprising:
 a plurality of dampeners adhered to each of the plurality of radial arms such that each of the plurality of dampeners form a ring around each of the bolt through holes.   
     
     
         18 . A microphone assembly comprising:
 a housing;   a flexible printed circuit board (PCB);   a bracket; and   a dampener coupled to the housing and the flexible PCB, wherein the dampener is coupled to the flexible PCB via a stiffener and tape;   
     
     
         19 . The microphone assembly of  claim 18  wherein a stiffness of the dampener is based on a modal analysis of a motor and a resonance of a motor shaft. 
     
     
         20 . The microphone assembly of  claim 18 , wherein the stiffness of the dampener is low on a condition that the resonance of the motor shaft is a low frequency, and wherein the stiffness of the dampener is high on a condition that the resonance of the motor shaft is a high frequency.