System comprising magnetically actuated motion control device

Abstract

A system that includes a magnetically actuated motion control device comprising a housing defining a cavity and including a slot therethrough. A movable member is located within the cavity and is movable relative to the housing. A magnetic field generator located on either the housing or the movable member causes the housing to press against the movable member to develop a friction force.

1 . A magnetically actuated motion control device, comprising a first housing member defining a cavity, said first housing member including a movable finger, a second member positioned within said first housing member cavity with said first housing member and said second member relatively movable, said first housing member includes an opening with said movable finger extending through said first housing member opening, and a magnetic field generator, said magnetic field generator generating a magnetic field and causing said movable finger to press against said second member to produce frictional damping. 
   
   
       2 . The magnetically actuated motion control device of  claim 1 , wherein said housing encircles said second member, said housing relatively rotatable around said second member. 
   
   
       3 . The magnetically actuated motion control device of  claim 1 , wherein said housing encircles said second member, said second member relatively rotatable within said housing. 
   
   
       4 . The magnetically actuated motion control device of  claim 1 , said device having a central axis with said first housing member and said second member relatively rotatable around the central axis. 
   
   
       5 . The magnetically actuated motion control device of  claim 1 , wherein said movable finger has a free end. 
   
   
       6 . A device according to  claim 1 , said movable finger having a tab end, said tab end extending through said first housing member opening. 
   
   
       7 . A device according to  claim 6 , wherein said movable finger has a second tab end, said second tab end extending through said first housing member opening. 
   
   
       8 . The magnetically actuated motion control device according to  claim 1  wherein said movable finger encircles said second member. 
   
   
       9 . The magnetically actuated motion control device according to  claim 1  wherein said movable finger is comprised of a circular band with a plurality of flex links. 
   
   
       10 . The magnetically actuated motion control device according to  claim 1  with a gap between said movable finger and said second member when a magnetic field is not generated by said magnetic field generator. 
   
   
       11 . The magnetically actuated motion control device of  claim 1 , wherein said second member has an outer surface and the movable finger has an inner surface and wherein the device further comprises a friction increasing material between said outer surface and said inner surface. 
   
   
       12 . The magnetically actuated motion control device of  claim 1 , wherein a lubricant is provided between said second member and the housing. 
   
   
       13 . The magnetically actuated motion control device of  claim 1  wherein said movable finger comprises a circular band, said circular band substantially encircling an outer circumference of said second member. 
   
   
       14 . The magnetically actuated motion control device of  claim 1 , wherein said second member is comprised of a circular stator having an outer circumference 
   
   
       15 . The magnetically actuated motion control device of  claim 1 , further comprising:
 a sensor positioned to sense a dynamic characteristic of one of the first housing member and the second member relative to the other of the first housing member and the second member.   
   
   
       16 . The magnetically actuated motion control device of  claim 1 , further comprising: a sensor positioned to sense a positional characteristic of one of the first housing member and the second member relative to the other of the first housing member and the second member. 
   
   
       17 . A magnetically actuated motion control device, comprising:
 a first housing member including a cavity formed therein and including a movable finger, said first housing member including an opening with said movable finger extending through said opening;   a second member disposed in the cavity; and   at least one magnetic field generator mounted to cause said movable finger to be displaced toward said second member and thereby squeeze said second member.   
   
   
       18 . The magnetically actuated motion control device of  claim 17 , wherein said second member is comprised of a circular stator having an outer circumference. 
   
   
       19 . The magnetically actuated motion control device of  claim 18 , wherein said movable finger is comprised of a circular band. 
   
   
       20 . The magnetically actuated motion control device of  claim 17 , wherein said movable finger has a free end. 
   
   
       21 . A device according to  claim 17 , said movable finger having a tab end, said tab end extending through said first housing member opening. 
   
   
       22 . A device according to  claim 21 , wherein said movable finger has a second tab end, said second tab end extending through said first housing member opening. 
   
   
       23 . The magnetically actuated motion control device according to  claim 17  wherein said movable finger is comprised of a circular band with a plurality of flex links. 
   
   
       24 . The magnetically actuated motion control device according to  claim 17  with a gap between said movable finger and said second member when a magnetic field is not generated by said magnetic field generator. 
   
   
       25 . The magnetically actuated motion control device of  claim 17 , wherein said second member has an outer surface and the movable finger has an inner surface and wherein the device further comprises a friction increasing material between said outer surface and said inner surface. 
   
   
       26 . The magnetically actuated motion control device of  claim 17 , wherein a lubricant is provided between said second member and the housing. 
   
   
       27 . The magnetically actuated motion control device of  claim 17 , further comprising: a sensor positioned to sense a dynamic characteristic of one of the first housing member and the second member relative to the other of the first housing member and the second member. 
   
   
       28 . The magnetically actuated motion control device of  claim 17 , further comprising: a sensor positioned to sense a positional characteristic of one of the first housing member and the second member relative to the other of the first housing member and the second member. 
   
   
       29 . A method of controlling relative motion, the method comprising the steps of:
 providing a housing having a finger and a second member, said second member and said housing relatively movable, the housing defining a cavity in which the second member is located, said housing member including an opening with said finger extending into said opening,   generating a magnetic field and   pressing said finger against the second member in accordance with said generated magnetic field.   
   
   
       30 . A method as claimed in  claim 29 , wherein said second member is a circular stator including a bobbin and a coil and said finger is magnetically permeable, wherein generating a magnetic field includes supplying a current from a current source to said coil to attract said finger towards said circular stator. 
   
   
       31 . A method as claimed in  claim 30 , said method including rotating said circular stator relative to said housing. 
   
   
       32 . A method as claimed in  claim 31 , wherein pressing said finger against said second member includes collapsing said finger around said circular stator. 
   
   
       33 . A method as claimed in  claim 29 , wherein said finger has a free end and pressing said finger against said second member includes collapsing said finger around said second member. 
   
   
       34 . A method as claimed in  claim 29 , wherein said finger has a tab end, said tab end extending through said housing opening. 
   
   
       35 . A method as claimed in  claim 34  wherein said finger has a second tab end, said second tab end extending through said housing opening. 
   
   
       36 . A method as claimed in  claim 29 , wherein said finger has a tab end, said tab end extending through said housing opening, and pressing said finger against said second member includes collapsing said finger around said second member. 
   
   
       37 . A method as claimed in  claim 29 , wherein said finger has a tab end, said tab end extending through said housing opening, and pressing said finger against said second member includes collapsing said finger around said second member, with a gap between said finger and said second member when a magnetic field is not generated by a magnetic field generator. 
   
   
       38 . A method as claimed in  claim 29 , wherein said second member has an outer surface and the finger has an inner surface and a friction increasing material is disposed between said outer surface and said inner surface. 
   
   
       39 . A method as claimed in  claim 29 , including positioning a sensor, said sensor positioned to sense a dynamic characteristic of one of the housing member and the second member relative to the other of the housing member and the second member. 
   
   
       40 . A method as claimed in  claim 29 , including providing a sensor, said sensor positioned to sense a positional characteristic of one of the housing member and the second member relative to the other of the housing member and the second member.