Access door

Abstract

An access door has an outer annular wall frame and an inner annular panel frame. The panel frame has a back flange parallel to but offset rearward from a wall face plane and having a planar front face formed with a forwardly projecting formation. It also has a rim flange projecting generally perpendicular to the plane forward from the outer edge of the back flange and having an annular inner face forming a corner with the front face of the back flange. A rigid panel set in the annular frame has an outer edge juxtaposed with the inner face of the rim flange, a back face spaced from the front face of the back flange, and a front face generally coplanar with a front edge of the rim flange. Adhesive in the space secures the panel to the panel frame.

1 . An access door comprising: 
 an annular wall frame adapted to be set in a wall or ceiling generally parallel to a front plane thereof;    an annular panel frame complementary to and fitting in the wall frame, generally of L-section, and having 
 a back flange generally parallel to but offset rearward from the plane, having an outer edge, and having a substantially planar front face formed with a forwardly projecting formation, and  
 a rim flange projecting generally perpendicular to the plane forward from the outer edge and having an annular inner face forming a corner with the front face of the back flange;  
   a rigid panel set in the annular frame and having an outer edge juxtaposed with the inner face of the rim flange, 
 a back face bearing on the formation, spacedly juxtaposed with the front face of the back flange, and forming an annular space extending along the projecting formation, and  
 a front face generally coplanar with a front edge of the rim flange; and  
 an annular mass of adhesive in the annular space between the front face of the back flange and the back face of the panel.  
   
   
   
       2 . The access door defined in  claim 1  wherein the rim flange is formed offset forward of the corner with an inwardly projecting ridge, the mass being trapped rearward of the ridge.  
   
   
       3 . The access door defined in  claim 2  wherein the mass is wholly trapped between the formation and the ridge.  
   
   
       4 . The access door defined in  claim 3  wherein the formation and ridge extend annularly around the respective flanges of the panel frame.  
   
   
       5 . The access door defined in  claim 1  wherein the formation is an annular ridge.  
   
   
       6 . The access door defined in  claim 1  wherein the formation is a multiplicity of teeth projecting forward from the back flange and poking into the back face of the panel.  
   
   
       7 . The access door defined in  claim 6  wherein the teeth are punched out of the back flange.  
   
   
       8 . The access door defined in  claim 6  wherein the back flange is formed with throughgoing holes through which the adhesive can be injected between the panel and the panel frame.  
   
   
       9 . The access door defined in  claim 8  wherein the rim flange is formed with throughgoing holes through which the adhesive can be injected between the panel and the panel frame.  
   
   
       10 . The access door defined in  claim 1  wherein the adhesive is a mixture including aluminum silicates and sodium silicate.