Cover for an outdoor tank

Abstract

The invention relates to a cover for an outdoor tank, the cover being made of a plate that can be treaded on and shifted between an open and a closed position, wherein the cover is guided displaceably on rails for opening and closing purposes in an at least approximately parallel fashion to the opening surface of the tank. A seal acting between the cover and the edge surface of the tank is brought into contact with the corresponding surface during the closing motion by such a relative movement that has a clear directional component, said directional component being normal on and directed toward said surface. The temperature of the surface from which the seal is removed when the cover is opened is automatically monitored and automatically raised by a heating element when the temperature falls below the freezing point.

1 . A cover for an outdoor tank, which cover consists of a board, can be walked on and can be moved between an open and a closed position, wherein, in order to open or close the cover, the latter can be moved guided on rails at least approximately parallel to the opening surface of the tank, wherein a seal is attached to one of the two parts, cover or edge surface, of the tank, irrespective of whether the cover is open or closed, and comes into contact with a sealing surface at the second part when the cover is closed and is released therefrom when the cover is opened, characterized in that, during the closing process, the seal is brought into contact at said second part by such a relative movement with respect to the surface, which movement has a clear directional component which is normal to this surface and is directed toward the latter, and in that the temperature of that surface from which the seal is released when the cover is opened is monitored automatically by a temperature sensor and is raised automatically by a heating device arranged in the vicinity if the temperature falls below freezing point. 
   
   
       2 . The cover as claimed in  claim 1 , characterized in that the rails on which the movement of the cover is guided during opening and closing are heated by a heating device arranged in their vicinity. 
   
   
       3 . The cover as claimed in  claim 1 , characterized in that the surface region between the rails which is located next to the tank is heated by a heating device arranged thereabove or therebelow. 
   
   
       4 . The cover as claimed in  claim 1 , characterized in that the cover is provided with rotatable rollers by means of which it rests on stationary rails such that it can travel, wherein those longitudinal regions of the rails on which the rollers lie when the cover is closed are lower than the adjacent longitudinal regions of the rails, directed toward the tank bottom, in the direction of the opening movement. 
   
   
       5 . The cover as claimed in  claim 1 , characterized in that the seal is attached to a profiled bar which is mounted such that it can rotate about an axis parallel to its longitudinal direction. 
   
   
       6 . The cover s claimed in  claim 1 , characterized in that the seal is attached to a profiled bar mounted such that it can move linearly parallel to its profile plane. 
   
   
       7 . The cover as claimed in  claim 1 , characterized in that it extends over an outer tank in which a smaller inner tank is arranged, wherein only the inner tank is filled with water, wherein the surfaces of the outer tank are designed to be thermally insulating and wherein at least one horizontal external dimension of the inner tank is much smaller than the horizontal internal dimension of the outer tank in the same direction. 
   
   
       8 . The cover as claimed in  claim 7 , characterized in that it is provided on its underside, in that surface region which is over the inner tank when the cover is closed, with an additional thermally insulating layer compared with other surface regions of the cover, which additional layer rests on the edge of the inner tank directly or by way of a seal when the cover is closed. 
   
   
       9 . The cover as claimed in  claim 7 , characterized in that it is provided, in the region of that surface which is over the inner tank when the cover is closed, with an opening closed by a tread-resistant insulating glass panel. 
   
   
       10 . The cover as claimed in  claim 7 , characterized in that the inner tank is a whirlpool.