Electrostatic operation device

Abstract

An electrostatic operation device in which a variation in the amount of electric charges accumulated in an electret film caused by physical impact can be suppressed. The electrostatic operation device (electrostatic induction power generating device ( 1 )) comprises movable electrodes ( 8 ), an electret film ( 5 ) so formed as to face the movable electrodes ( 8 ) at a space therebetween, and a stopper ( 401 b ) for suppressing the approach of the movable electrodes ( 8 ) to the electret film ( 5 ) within a predetermined space.

1 . An electrostatic operation device comprising:
 a first electrode ( 8 ,  8   a ,  24 ,  24   a ,  62 ,  93 );   an electret film ( 5 ,  5   a ,  13 ,  43 ,  43   a  to  43   i ,  91 ) so formed as to be opposed to said first electrode at an interval therebetween; and   a member ( 9 ,  9   a ,  14 ,  14   a  to  14   c ,  42 ,  94 ,  94   a ,  94   b ,  96   a  to  96   c ,  401   b ,  412   a  to  412   f ,  413   c ,  612   d ) inhibiting said first electrode and said electret film from moving close to each other within a prescribed interval.   
   
   
       2 . The electrostatic operation device according to  claim 1 , further comprising a second electrode ( 4 ,  4   a ,  12 ,  41 ,  41   a  to  41   f ,  90 ) so provided as to be opposed to said first electrode at an interval therebetween. 
   
   
       3 . The electrostatic operation device according to  claim 2 , wherein
 an end of a surface of said member on a side of one of said first electrode and said second electrode is chamfered.   
   
   
       4 . The electrostatic operation device according to  claim 2 , further comprising a first substrate ( 21 ,  21   b ) formed with said first electrode and a second substrate ( 11 ) formed with said second electrode, wherein
 said member is formed on a surface of one of said first substrate and said second substrate.   
   
   
       5 . The electrostatic operation device according to  claim 2 , further comprising a first substrate ( 92 ) formed with said first electrode, wherein
 said member is provided on a position between said first substrate and said second electrode at intervals from said first substrate and said second electrode.   
   
   
       6 . The electrostatic operation device according to  claim 2 , further comprising a protective film ( 97 ) formed to cover a surface not formed with said electret film in the surfaces of said first and second electrodes. 
   
   
       7 . The electrostatic operation device according to  claim 1 , wherein
 said member has a function as a stopper inhibiting said first electrode and said electret film from coming into contact with each other or a spacer keeping an interval between said first electrode and said electret film constant.   
   
   
       8 . The electrostatic operation device according to  claim 1 , further comprising a guard electrode ( 15 ,  15   a ) for inhibiting a component other than a component in a direction perpendicular to a main surface of said electret film in an electric field resulting from electric charges stored in said electret film from generation, provided to be adjacent to said electret film. 
   
   
       9 . The electrostatic operation device according to  claim 8 , further comprising a second electrode so provided as to be opposed to said first electrode at an interval therebetween, wherein
 said member is so formed as to be stacked on a surface of said guard electrode on a side of one of said first electrode and said second electrode.   
   
   
       10 . The electrostatic operation device according to  claim 1 , wherein
 said member inhibiting said first electrode and said electret film from moving close to each other within the prescribed interval functions as a guard electrode for inhibiting a component other than a component in a direction perpendicular to a main surface of said electret film in an electric field resulting from electric charges stored in said electret film from generation, provided to be adjacent to said electret film.   
   
   
       11 . The electrostatic operation device according to  claim 1 , further comprising a first substrate ( 21   a ) formed with said first electrode, wherein
 said first electrode is embedded in said first substrate.   
   
   
       12 . The electrostatic operation device according to  claim 1 , wherein
 said member is formed between said electret film and said first electrode.   
   
   
       13 . The electrostatic operation device according to  claim 1 , further comprising a first substrate formed with said first electrode, wherein
 said first substrate is supported by said member to be able to vibrate.   
   
   
       14 . The electrostatic operation device according to  claim 1 , further comprising a second substrate ( 90 ) formed with said electret film, wherein
 said second substrate is supported by said member to be able to vibrate.   
   
   
       15 . The electrostatic operation device according to  claim 1 , further comprising a groove shaped recess portion ( 401   a ,  411   a  to  411   f ,  421 ) and a projecting portion ( 401   b ,  412   a  to  412   f ) provided on a surface of one of said first electrode and said second electrode, wherein
 said electret film is so formed as to be embedded in at least a bottom surface of said recess portion.   
   
   
       16 . The electrostatic operation device according to  claim 15 , wherein
 said groove shaped recess portion is so formed that a width is increased from a bottom surface of said recess portion toward an open upper end thereof.   
   
   
       17 . The electrostatic operation device according to  claim 15 , wherein
 a conductive layer is formed on a surface of said projecting portion.   
   
   
       18 . The electrostatic operation device according to  claim 15 , wherein
 an insulating film ( 45   a ,  45   b ) having a smaller breakdown voltage than said electret film is formed on a surface of said projecting portion.   
   
   
       19 . The electrostatic operation device according to  claim 15 , wherein
 said electret film is formed on the bottom surface of said recess portion to have a thickness smaller than a depth of said recess portion.   
   
   
       20 . The electrostatic operation device according to  claim 15 , wherein
 an end of a surface of said projecting portion on a side of one of said first electrode and said second electrode is formed in a rounded shape or a chamfered shape.   
   
   
       21 . The electrostatic operation device according to  claim 15 , wherein
 a charge outflow inhibition film ( 46 ,  48 ) is formed on a surface of said electret film.   
   
   
       22 . The electrostatic operation device according to  claim 15 , wherein
 said electret film formed to be embedded in said groove shaped recess portion is oblongly formed in plan view.   
   
   
       23 . The electrostatic operation device according to  claim 1 , wherein
 said member is formed on a surface of said electret film.   
   
   
       24 . The electrostatic operation device according to  claim 23 , wherein
 at least a part of said member is formed by a member softer than said electret film.   
   
   
       25 . The electrostatic operation device according to  claim 23 , further comprising a conductive layer ( 10 ) formed on a surface of said member. 
   
   
       26 . The electrostatic operation device according to  claim 23 , wherein
 said member is so formed that a width is reduced toward a side on which said electret film is not formed.   
   
   
       27 . An electrostatic operation device comprising:
 a first electrode ( 62 );   a second electrode ( 62   a ) provided to be adjacent to said first electrode at an interval therebetween;   an electret film ( 5   b ) formed to be opposed to said first electrode and said second electrode; and   a member ( 9   b ) having a function as a stopper inhibiting said first and second electrodes and said electret film from coming into contact with each other or a spacer keeping an interval between said first and second electrodes and said electret film constant, between said first and second electrodes and said electret film.   
   
   
       28 . An electrostatic operation device comprising:
 a first electrode ( 62 );   a second electrode ( 62   a ) provided to be adjacent to said first electrode at an interval therebetween;   a substrate ( 4   b ) to be opposed to said first electrode and said second electrode and provided with a projecting portion ( 401   c ) and a recess portion ( 401   d ); and   an electret film ( 5   b ) formed to be embedded in a bottom surface of said recess portion provided on said substrate, wherein   said projecting portion provided on said substrate has a function as a stopper inhibiting said first and second electrodes and said electret film from coming into contact with each other or a spacer keeping an interval between said first and second electrodes and said electret film constant.