The Director-General of the Institute of Space and Astronautical Science

Japan Aerospace Exploration Agency

Fujikura Parachute Company, Ltd

Japan Aerospace Exploration Agency, an Independent Administrative Institution

Independent Administrative Institution, the Japan Aerospace Exploration Agency

Naoki Izutsu

Nobuyuki Yajima

Hideyuki Honda

Kiyoho Matsushima

A pressure tight large-scaled membrane structure includes a bag body having a plurality of gores attached to each other along an attachment line, and a plurality of first ropes attached over a predetermined range of the bag body in such a manner as to be orthogonal to the attachment line of the gores, whereby a cylindrical shaped portion is formed. The cylindrical shaped portion has a substantially circular cross-sectional area that is a maximum substantially circular cross-section of the bag body and the plurality of first ropes each having approximately the same length as a circumference of the substantially circular-cross section having a maximum area with respect to the bag body.

Pressure tight large-scaled membrane structure

A membrane structure includes an airtight pressure-resistant gasbag and a shape maintaining mechanism which maintains the gasbag in a predetermined shape when the gasbag is in a fully inflated state. The gasbag includes a plurality of spindle-shaped gores of an airtight membrane material, adjacent gores joined together at edges, and a plurality of reinforcing ropes attached to joined sections of the edges, the reinforcing ropes extending along the edges, respectively. Each of the gores outwardly protrudes between two adjacent reinforcing ropes extending along the edges of the gore, respectively, without elongation of the airtight membrane material, when the gasbag is in the fully inflated state. Each protruding gore has a radius of curvature in a direction intersecting the two adjacent reinforcing ropes. The radius of curvature is smaller than a radius of the gasbag.

Membrane structure

A gas X is sealed into a test film bag, which is obtained by processing a test plastic film into a bag, and has a known mass and surface area. The mass of the test film bag in which the gas is sealed is measured by an electronic balance a plurality of numbers of times on the time series while the temperature is kept constant in a constant temperature vessel which is filled with a gas Y different from the gas X so as to make the pressure in the vessel equal to the internal pressure of the test film bag. A transmission rate associated with the gas X is then computed from the relationship between the measurement results, the mass of the test film bag alone, and the surface area by a computer.

Method of measuring gas transmission rate of plastic film and measuring apparatus and computer program product used therefor

A pressure-resistant balloon includes a gasbag and a volume changing mechanism which deforms the gasbag in a fully inflated state to change a volume of the gasbag. The gasbag includes spindle-shaped gores of an airtight film material, adjacent gores joined together at side edges, and load tapes fitted to joined sections of the side edges, and extending along the side edges, respectively. After inflated, the gasbag allows no gas to be discharged so as to maintain an internal gas pressure. Each of the gores outwardly protrudes between two adjacent load tapes without an elongation of the airtight film material of the gore, when the gasbag is in the fully inflated state. The protruding gore has a radius of curvature in a direction intersecting with the two adjacent load tapes. The radius of curvature is smaller than a radius of the gasbag.

Pressure-resistant balloon

A balloon comprising an envelope, wherein the envelope has a multilayered structure comprising a gas-impervious sheet, and a liquid absorbent sheet overlaid on the inner surface of the gas-impervious sheet.

Balloon

Based on a shape of gores of the Natural-Shaped Balloon, side edge parts of gores having a large width and a large length are connected to load tapes of a length equal to a circumferential length of a side edge part of the gores of the Natural-Shaped Balloon, in a state that wrinkles are formed uniformly and shortened on the side edge parts of the gores. As these gores are swollen out from between the load tapes from the beginning, the radius of curvature of the gores becomes small and the tension against the internal pressure of gas within a gas bag becomes small, so that higher pressure resistance is obtained. Further, a manufacturing method of the present invention is for connecting the side edge parts of the gores with the load tapes while shortening the length of the side edge parts. Thus, it is possible to efficiently manufacture this super-pressure balloon.

Growing community of inventors

Sagamihara, Japan

Naoki Izutsu