Magnetic retention device

Abstract

An apparatus, including an external component of a medical device configured to generate a magnetic flux that removably retains, via a resulting magnetic retention force, the external component to a recipient thereof, wherein the external component is configured to enable the adjustment of a path of the generated magnetic flux so as to vary the resulting magnetic retention force.

What is claimed is: 
     
         1 . An apparatus, comprising:
 an external component of a medical device; and   an implantable component of the medical device, wherein   the apparatus is configured to generate a magnetic flux that removably retains, via a resulting magnetic retention force, the external component to a recipient thereof, wherein the external apparatus is configured to enable the adjustment of a path of the generated magnetic flux so as to vary the resulting magnetic retention force.   
     
     
         2 . The apparatus of  claim 1 , wherein:
 the external component is configured to enable adjustment of the path of the generated magnetic flux, wherein adjustment of the path is relative to a global orientation of the external component.   
     
     
         3 . The apparatus of  claim 1 , wherein:
 the external component includes a skin interface surface;   the adjustment of the path is relative to a direction normal to the skin interface surface.   
     
     
         4 . The apparatus of  claim 1 , wherein:
 the external component includes a permanent magnet that generates at least a portion of the generated magnetic flux; and   the external component is configured to enable tilting of the permanent magnet, thereby adjusting the path of the generated magnetic flux.   
     
     
         5 . The apparatus of  claim 4 , wherein:
 the external component includes a skin interface surface; and   the apparatus is configured such that:
 the tilting of the permanent magnet entails adjusting a longitudinal axis thereof relative to the skin interface surface; 
 tilting the permanent magnet such that an angle between the longitudinal axis and an axis normal to the skin interface surface is increased decreases the resulting magnetic retention force; and 
 tilting the permanent magnet such that an angle between the longitudinal axis and an axis normal to the skin interface surface is decreased increases the resulting magnetic retention force. 
   
     
     
         6 . The apparatus of  claim 1 , wherein:
 the external component includes a permanent magnet that generates at least a portion of the generated magnetic flux; and   the external component is configured to enable rotation of the permanent magnet, thereby adjusting the path of the generated magnetic flux.   
     
     
         7 . The apparatus of  claim 6 , wherein:
 the external component is further configured to enable adjustment of the generated magnetic flux to vary the resulting retention force via at least one of additive or subtractive interaction of local magnetic flux.   
     
     
         8 . The apparatus of  claim 1 , further comprising:
 an implantable component that interacts with the magnetic flux to establish retention of the external component to the recipient, wherein   the apparatus is configured such that a torque applied to skin of the recipient is substantially constant through a substantial range of adjustments of the path of the generated magnetic flux.   
     
     
         9 . An apparatus, comprising:
 an external component of a medical device including a permanent magnet having a polarity axis, the external component being configured such that the permanent magnet at least partially removably retains, via a resulting magnetic retention force, the external component to a recipient thereof, wherein the external component is configured to enable the adjustment of an orientation of the polarity axis.   
     
     
         10 . The apparatus of  claim 9 , wherein:
 the external component is configured to enable the adjustment of the generated magnetic flux without additive and subtractive interaction of local magnetic flux.   
     
     
         11 . The apparatus of  claim 10 , wherein:
 the external component is further configured to enable the adjustment of the generated magnetic flux via at least one of additive and subtractive interaction of local magnetic flux.   
     
     
         12 . The apparatus of  claim 9 , wherein:
 the permanent magnet is a first permanent magnet having a first polarity axis; and   the apparatus further comprises:
 a second permanent magnet having a second polarity axis, wherein 
   the external component is configured such that the second permanent magnet contributes to the resulting magnetic retention force so as to at least partially removably retain, via the resulting magnetic retention force, the external component to a recipient thereof, and   the external component is configured to enable the adjustment of an orientation of the second polarity axis.   
     
     
         13 . The apparatus of  claim 12 , wherein:
 the external component is configured to enable at least one of rotation and tilting of the first and second permanent magnets to adjust the orientations of the respective first and second polarity axes.   
     
     
         14 . The apparatus of  claim 9 , wherein:
 the permanent magnet is a first permanent magnet having a first polarity axis; and   the apparatus further comprises:
 a second permanent magnet having a second polarity axis, wherein 
 the external component is configured such that the second permanent magnet contributes to the resulting magnetic retention force so as to at least partially removably retain, via the resulting magnetic retention force, the external component to a recipient thereof, and 
 the external component is configured to enable the adjustment of an orientation of the second polarity axis; 
 a third permanent magnet having a third polarity axis, wherein 
 the external component is configured such that the third permanent magnet contributes to the resulting magnetic retention force so as to at least partially removably retain, via the resulting magnetic retention force, the external component to a recipient thereof, and 
 the external component is configured to enable the adjustment of an orientation of the third polarity axis; and 
 a fourth permanent magnet having a fourth polarity axis, wherein 
 the external component is configured such that the fourth permanent magnet contributes to the resulting magnetic retention force so as to at least partially removably retain, via the resulting magnetic retention force, the external component to a recipient thereof, and 
 the external component is configured to enable the adjustment of an orientation of the fourth polarity axis. 
   
     
     
         15 . The apparatus of  claim 14 , wherein:
 the apparatus is configured such that a resulting magnetic flux of the external component establishing the resulting magnetic retention force is substantially symmetrical about a plane parallel to a longitudinal axis of the external component throughout a range of orientations of the polar axes of the first, second third and fourth permanent magnets.   
     
     
         16 . The apparatus of  claim 14 , further comprising:
 the apparatus is configured such that a resulting magnetic flux of the external component establishing the resulting magnetic retention force is substantially symmetrical about the longitudinal axis of the external component throughout a range of orientations of the polar axes of the first, second, third and fourth permanent magnets.   
     
     
         17 . The apparatus of  claim 12 , wherein:
 the apparatus includes a mechanical adjustment apparatus that simultaneously adjusts the respective orientations of the first and second permanent magnets so that the first and second poles have equal and opposite adjustments relative to a longitudinal axis of the external component.   
     
     
         18 . The apparatus of  claim 9 , wherein:
 the permanent magnet is a first permanent magnet having a first polarity axis; and   the apparatus further comprises:
 a second permanent magnet having a second polarity axis, wherein 
 the external component is configured such that the second permanent magnet contributes to the resulting magnetic retention force so as to at least partially removably retain, via the resulting magnetic retention force, the external component to a recipient thereof, and 
 the external component is configured to enable the adjustment of an orientation of the second polarity axis; and 
 a third permanent magnet having a third polarity axis, wherein 
 the external component is configured such that the third permanent magnet contributes to the resulting magnetic retention force so as to at least partially removably retain, via the resulting magnetic retention force, the external component to a recipient thereof. 
   
     
     
         19 . A method, comprising:
 obtaining an external component of a medical device configured to be magnetically retained against outer skin of a recipient via a magnetic coupling between the external component and an implanted component in the recipient; and   adjusting a path of a magnetic flux generated by at least one of the external component or the implanted component such that the resulting retention force of the magnetic retention for the recipient is varied from that which was the case prior to the adjustment.   
     
     
         20 . The method of  claim 19  further comprising:
 placing the external component against a recipient's skin at least one of during or after adjusting the path such that the external component is retained against the skin of the recipient via the magnetic coupling between the external component and the implanted component, wherein 
 the implanted component includes a magnet arrangement having a single polarity axis, and 
 the magnetic coupling results in substantially no torque on the external component while positioned against the skin of the recipient in the absence of external forces on the external component. 
 
     
     
         21 . The method of  claim 19 , further comprising:
 placing the external component against a recipient's skin at least one of after or during adjusting the path such that the external component is retained against the skin of the recipient via the magnetic coupling between the external component and the implanted component, wherein   the implanted component includes a magnet arrangement having a single polarity axis, and   the resulting magnetic flux of the magnetic flux generated by the external component and the magnet of the implanted component is symmetrical about a plane parallel to and lying on the single polarity axis.   
     
     
         22 . The method of  claim 19 , further comprising:
 placing the external component against a recipient's skin after adjusting the path such that the external component is retained against the skin of the recipient via the magnetic coupling between the external component and the implanted component, wherein   the implanted component includes a magnet arrangement having a single polarity axis, and   the resulting magnetic flux of the magnetic flux generated by the external component and the magnet of the implanted component is symmetrical about a the single polarity axis.   
     
     
         23 . The method of  claim 19 , further comprising:
 placing the external component against a recipient's skin at least one of during or after adjusting the path such that the external component is retained against the skin of the recipient via the magnetic coupling between the external component and the implanted component, wherein   the implanted component includes a magnet arrangement having a multiple polarity axes, and   the resulting magnetic flux of the magnetic flux generated by the external component and the magnet of the implanted component is symmetrical about a plane parallel to and lying in between respective axes of the multiple polarity axes.   
     
     
         24 . The method of  claim 18 , wherein:
 the action of adjusting the path of the magnetic flux entails adjusting a trajectory of the magnetic flux between the external component and the implantable component.   
     
     
         25 . The method of  claim 18 , wherein:
 the action of adjusting the path of the magnetic flux results in lengthening the path between the external component and the implantable component relative to that which was the case prior to the adjustment for the same air gap between respective magnetic components of the external component and respective magnetic components of the implantable component, and   the resulting retention force is reduced as a result of the lengthening of the path relative to that which was the case prior to the adjustment of the path.