US Patent 10350345 Cylindrical collapsible container

A container for medical use forming a closed compartment for carrying a pressurized liquid includes a side wall member; a rigid bottom portion; a rigid top portion having a through hole; a lid arranged to cover and seal a filling hole; a pressure valve; and a flexible tube arranged inside the closed compartment. The first end of the flexible tube being provided with an opening towards the closed compartment and the second end of the flexible tube is connected to the top portion and in fluid communication with the through hole in the rigid top portion. The side wall member is flexible such that said container is reversibly foldable and unfoldable to be arrangeable in a compact state and an expanded state.