Diaphragm

Abstract

Disclosed is a diaphragm having a flexible film portion and an outer peripheral flange portion integrally provided on the peripheral edge of the film portion, said outer peripheral flange portion being provided between and held by a first housing and a second housing, wherein the film portion is prevented from rising upward when the diaphragm is attached to the housings. The outer peripheral flange portion has a first pressed surface which is one surface of the diaphragm in the thickness direction and which is in close contact with the first housing, and a three-dimensional shape composed of a projected portion or a recessed portion, on the first pressed surface. When the outer peripheral flange portion is attached to the first housing and the second housing while being compressed and deformed therebetween, the three-dimensional shape defines voids in the thickness direction between the outer peripheral flange portion and the first housing.

1 - 5 . (canceled) 
     
     
         6 . A diaphragm comprising a flexible film portion and an outer peripheral flange portion integrally provided on a peripheral edge of the film portion,
 wherein at least a portion of one surface in the thickness direction of the film portion and at least a portion of one end surface in the thickness direction of the outer peripheral flange portion are arranged on the same plane to be a flat surface,   wherein another end surface in the thickness direction of the outer peripheral flange portion protrudes more in the thickness direction than another surface in the thickness direction of the film portion,   wherein, when the diaphragm is attached between a pair of a first housing and a second housing, the outer peripheral flange portion becomes to be a state compressed between the first housing and the second housing, and the film portion becomes to be a state in which one surface of the film portion in the thickness direction is in contact with the first housing over the approximately whole surface of the one surface of the film portion,   wherein the one end surface in the thickness direction of the outer peripheral flange portion includes a first pressed surface contacting the first housing, and a three dimensional shape comprising a projected portion or a recessed portion is provided on the first pressed surface,   wherein, when the outer peripheral flange portion is compressed in the thickness direction between a pair of the first housing and the second housing, the three-dimensional shape defines voids in the thickness direction between the outer peripheral flange portion and the first housing,   wherein the voids in the thickness direction absorbs compression and deformation of the outer peripheral flange portion, so that the influence of the compression and deformation hardly reaches to the film portion, and rising upward of the film portion from the first housing is prevented.   
     
     
         7 . The diaphragm according to  claim 6 ,
 wherein the three-dimensional shape is an annular projection provided on a center portion in the diameter direction of the first pressed surface,   wherein, when the outer peripheral flange portion is attached to the first housing and the second housing while being compressed and deformed therebetween, the three-dimensional shape defines voids in the diameter direction on the more outer side than the annular projection on the first pressed surface.   
     
     
         8 . The diaphragm according to  claim 6 ,
 wherein, when the outer peripheral flange portion is attached between the first housing and the second housing, the outer peripheral flange portion is set to have an outer diameter size enabling to define voids in the diameter direction between the outer peripheral surface of the outer peripheral flange portion and at least one of the first housing and the second housing, in the diameter direction of the diaphragm.   
     
     
         9 . The diaphragm according to  claim 6 ,
 wherein the outer peripheral flange portion includes a second pressed surface and a three-dimensional shape,   wherein the second pressed surface is another surface in the thickness direction of the diaphragm and is pressed by the second housing,   wherein the three-dimensional shape includes a projected portion or a recessed portion on the second pressed surface.   
     
     
         10 . A diaphragm supporting structure sandwiching a diaphragm by a first housing and a second housing,
 wherein the diaphragm supporting structure includes the diaphragm according to  claim 6  as the diaphragm.   
     
     
         11 . The diaphragm according to  claim 7 ,
 wherein, when the outer peripheral flange portion is attached between the first housing and the second housing, the outer peripheral flange portion is set to have an outer diameter size enabling to define voids in the diameter direction between the outer peripheral surface of the outer peripheral flange portion and at least one of the first housing and the second housing, in the diameter direction of the diaphragm.   
     
     
         12 . The diaphragm according to  claim 8 ,
 wherein the outer peripheral flange portion includes a second pressed surface and a three-dimensional shape,   wherein the second pressed surface is another surface in the thickness direction of the diaphragm and is pressed by the second housing,   wherein the three-dimensional shape includes a projected portion or a recessed portion on the second pressed surface.   
     
     
         13 . A diaphragm supporting structure sandwiching a diaphragm by a first housing and a second housing,
 wherein the diaphragm supporting structure includes the diaphragm according to  claim 9  as the diaphragm.