Implantable actuator for hearing aid application

Abstract

An electromechanical actuator for an implantable hearing aid device including a mechanical output structure that has a first portion and a second portion, wherein the first portion is a mechanical attachment structure to attach a stapes prosthesis, and wherein the second portion is a wire-like member coupling the mechanical attachment structure to a magnetically permeable armature shaft assembly.

1 .- 33 . (canceled) 
     
     
         34 . An electromechanical actuator comprising:
 first and second magnets arranged to provide a biasing field in a field region between two substantially opposed pole faces of said first and second magnets;   a magnetically permeable armature located in said biased field region between said opposed pole faces, the location of the magnetically permeable armature defining a first and second working gap between the magnetically permeable armature and respective opposed pole faces of the first and second magnets; and   a shaft supporting said magnetically permeable armature, said shaft arranged to allow movement of said magnetically permeable armature between said opposed pole faces in a longitudinal direction defined by the movement of said shaft, wherein   the actuator is configured to generate a signal flux to modulate said biasing field in said field region thereby providing an unbalanced force to said magnetically permeable armature causing actuation of said shaft.   
     
     
         35 . The actuator of  claim 34 , wherein:
 said opposed pole faces facing in a longitudinal direction of the actuator;   the shaft is part of a magnetically permeable armature shaft assembly extending in a longitudinal direction of the actuator and supporting said magnetically permeable armature, said magnetically permeable armature shaft assembly arranged to allow movement of said magnetically permeable armature between said opposed pole faces in said longitudinal direction;   the actuator is configured to provide a biasing force to said magnetically permeable armature shaft assembly to bias said magnetically permeable armature to a predetermined location between said opposed pole faces;   the actuator is configured to generate a magnetic flux responsive to an input signal to generate the signal flux to modulate the biasing field in said field region thereby providing the unbalanced force to said magnetically permeable armature causing actuation of said magnetically permeable armature shaft assembly; and   the actuator further comprises:
 a mechanical output structure configured to stimulate the inner ear auditory system responsive to actuation of said magnetically permeable armature shaft assembly, wherein said mechanical output structure has a first portion and a second portion, and wherein the first portion is a mechanical attachment structure to attach a stapes prosthesis, and wherein said second portion is a wire-like member coupling said mechanical attachment structure to said magnetically permeable armature shaft assembly. 
   
     
     
         36 . The actuator of  claim 34 , wherein:
 the shaft is a magnetically permeable armature shaft.   
     
     
         37 . A hearing prosthesis, comprising:
 the actuator of  claim 34 , wherein the actuator is configured to provide mechanical stimulation to an ear component inside of the tympanic membrane so as to evoke a hearing percept.   
     
     
         38 . The actuator of  claim 34 , further comprising:
 an electrical coil which is fixed relative to the permanent magnets, wherein the actuator is configured such that the application of an input signal to the electrical coil generates the signal flux to modulate the biasing field.   
     
     
         39 . The actuator of  claim 34 , wherein:
 the signal flux is generated using a coil that is fixed relative to movement of the armature during actuation of the actuator.   
     
     
         40 . The actuator of  claim 34 , wherein:
 respective spans of the first and second working gaps are inversely variable during actuation of the actuator.   
     
     
         41 . The actuator of  claim 34 , wherein:
 the first and second magnets are arranged such that the between region extends from the first magnet to the second magnet in the direction of actuator stroke.   
     
     
         42 . The actuator of  claim 34 , wherein:
 the first and second magnets are arranged such that the two substantially opposed pole faces of said first and second magnets are normal to a longitudinal direction of the shaft.   
     
     
         43 . The actuator of  claim 34 , further comprising:
 an electrical coil which is offset from the first and second magnets in a longitudinal direction of the shaft during all actuation movements of the shaft.   
     
     
         44 . The actuator of  claim 34 , wherein:
 the actuator is an implantable actuator.   
     
     
         45 . The actuator of  claim 34 , further comprising:
 a prosthetic attachment component mechanically linked to the shaft, wherein the prosthetic attachment component is configured to attach to a middle ear component of a recipient.   
     
     
         46 . The actuator of  claim 34 , further comprising at least one of:
 an artificial incus mechanically linked to the shaft; or   a stapes prosthesis mechanically linked to the shaft.   
     
     
         47 . The actuator of  claim 34 , wherein:
 said opposed pole faces of the first and second magnets are oriented facing toward each other in said longitudinal direction.   
     
     
         48 . An electromechanical actuator comprising:
 first and second permanent magnets establishing a gap therebetween; and   a coil assembly, including a coil, configured to generate a signal flux, wherein   the coil of the coil assembly is located outside of the gap, and   the electromechanical actuator is configured to modulate a polarizing flux generated by the first and second permanent magnets, thereby actuating the actuator, due to generation of the signal flux by the coil assembly.   
     
     
         49 . The actuator of  claim 48 , wherein:
 modulation of the polarizing flux increases or decreases a flux in the gap depending on a direction of current passing through the coil.   
     
     
         50 . The actuator of  claim 48 , wherein:
 modulation of the polarizing flux increases or decreases a flux in the gap depending on a direction of current passing through the coil.   
     
     
         51 . The actuator of  claim 48 , further comprising:
 an armature movably located between the first permanent magnet and the second permanent magnet in the gap, wherein a first working gap is located between a first side of the armature and the first permanent magnet, and a second working gap is located between a second side of the armature and the second permanent magnet, wherein   the actuator is configured such that a constant polarizing flux is present in the first working gap which results in a net force pulling the armature towards the first permanent magnet.   
     
     
         52 . The actuator of  claim 52 , further comprising:
 the actuator is configured so as to variably increase and decrease an attractive force in the second working gap, thereby actuating the actuator.   
     
     
         53 . The actuator of  claim 48 , further comprising:
 an armature movably located between the first permanent magnet and the second permanent magnet in the gap, wherein a first working gap is located between a first side of the armature and the first permanent magnet, and a second working gap is located between a second side of the armature and the second permanent magnet, wherein   the actuator is configured so as to variably increase and decrease an attractive force in the second working gap, thereby actuating the actuator.   
     
     
         54 . The actuator of  claim 53 , wherein:
 an attractive force is present between the armature and the first permanent magnet in the first working gap, and   the variable increase and decrease in the attractive force in the second working gap, overcomes the attractive force in the first working gap, thereby actuating the actuator.   
     
     
         55 . The actuator of  claim 48 , further comprising:
 an armature movably located between the first permanent magnet and the second permanent magnet in the gap, wherein a first working gap is located between a first side of the armature and the first permanent magnet, and a second working gap is located between a second side of the armature and the second permanent magnet, wherein   the actuator is configured to modulate a first polarizing flux in the first working gap while maintaining a constant polarizing flux in the second working gap, thereby actuating the actuator.   
     
     
         56 . An electromechanical actuator comprising:
 first and second permanent magnets establishing a gap therebetween; and   an armature movably located between the first permanent magnet and the second permanent magnet in the gap, wherein a first working gap is located between a first side of the armature and the first permanent magnet, and a second working gap is located between a second side of the armature and the second permanent magnet, wherein   the actuator is configured so as to variably increase and decrease an attractive force in the second working gap, such that the size of the second working gap varies, thereby actuating the actuator, the attractive force begin at least partially based on the magnetic effects of the first and second magnets on the armature.   
     
     
         57 . The actuator of  claim 56 , wherein:
 the electromechanical actuator is configured to modulate a polarizing flux generated by the first and second permanent magnets, thereby actuating the actuator.   
     
     
         58 . The actuator of  claim 56 , wherein:
 the electromechanical actuator is configured to maintain a constant polarizing flux in the first working gap.   
     
     
         59 . The actuator of  claim 56 , further comprising:
 a signal coil, wherein,   the electromechanical actuator is configured to generate a signal flux by changing a direction of current passing through the signal coil; and   the electromechanical actuator is configured to increase and decrease an attractive force in the second air gap as a result of the generated signal flux, thereby actuating the actuator.   
     
     
         60 . The actuator of  claim 56 , further comprising:
 a signal coil, wherein,   the electromechanical actuator is configured to generate a signal flux by changing a direction of current passing through the signal coil; and   the electromechanical actuator is configured to conduct the signal flux from a location outside of the gap to a location inside the gap so as to modulate a polarizing flux generated by the first and second magnets, thereby actuating the actuator.   
     
     
         61 . A hearing prosthesis, comprising:
 the actuator of  claim 56 , wherein the actuator is part of an implantable component of a middle ear implant.   
     
     
         62 . The actuator of  claim 56 , further comprising:
 a prosthetic attachment component mechanically linked to the armature, wherein the prosthetic attachment component is configured to attach to a middle ear component of a recipient.   
     
     
         63 . The actuator of  claim 48 , further comprising:
 a mechanical output structure configured to stimulate the inner ear auditory system responsive to actuation of said actuator, wherein said mechanical output structure has a first portion and a second portion, wherein the first portion is a mechanical attachment structure to attach a stapes prosthesis, and wherein said mechanical attachment structure is of substantially cylindrical shape with an elliptical cross section having a numeric eccentricity ranging from approximately 0 to approximately 0.5.   
     
     
         64 . The actuator of  claim 48 , further comprising:
 a mechanical output structure configured to stimulate the inner ear auditory system responsive to actuation of said actuator, wherein said mechanical output structure has a first portion and a second portion, and wherein the first portion is a mechanical attachment structure to attach a stapes prosthesis, and wherein said second portion is a wire-like member coupling said mechanical attachment structure a shaft that is actuated upon actuation of the actuator, and wherein said wire-like member is a straight rod, and further wherein an angle between said mechanical attachment structure and said straight rod is chosen in the range of approximately 80° to approximately 150°.