Pressure sensing means and method for making a pressurized container means and system utilizing the same

Claim 1

In combination, a container means having a pressurized fluid therein, and fluid operated sensing means carried by said container means for sensing pressure changes within said container means, said sensing means and said container means being so constructed and arranged that said sensing means is temperature compensated by being disposed within said container means to be substantially surrounded by a reference pressure of said fluid of said container means so that pressure changes of said fluid in said container means caused by temperature changes thereof are ineffective to cause sensing thereof by said sensing means as the fluid of said sensing means is at the same temperature as said fluid in said container means, said fluid operated sensing means and said container means having been initially charged with their respective pressurized fluids to substantially the same pressure levels, said sensing means comprising a housing means secured in said container and having a chamber therein, a double wall fluid operated device disposed in said chamber of said housing means and being carried by the same, said walls of said device defining a chamber therebetween, said device having passage means interconnecting said chamber of said device to the exterior of said housing means so as to be in fluid communication with said fluid in said container means, and a charge of pressure fluid sealed in said chamber of said housing means to provide said pressurized fluid of said sensing means, said charge of fluid in said chamber of said housing means being adapted to hold said walls of said device in intimate contact with each other throughout the entire effective surface areas thereof so that the same will not take a permanent set when the chamber therebetween is at atmospheric conditions.