RU2611668C1 - Method of strengthening of inflated constructions (versions) - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: invention is relevant to small-size shipbuilding and ships of special purpose. It proposes four approaches to intensifying inflated constructions. Upon the first approach shell structure is used for strengthening of inflated constructions. This structure is strained by force of excess pressure of working environment. Inflated plane truss is fastened into the mentioned structure along symmetry axis. Upon the second approach shell structure is used for strengthening of inflated constructions. This structure is strained by force of excess pressure of working environment. Solid plane truss is fastened into the mentioned structure along symmetry axis. Upon the third approach shell structure is used for strengthening of inflated constructions. This structure is strained by force of excess pressure of working environment. Solid truss is fastened into the mentioned structure along symmetry axis. Upon the fourth approach shell structure is used for strengthening of inflated constructions. This structure is strained by force of excess pressure of working environment. Space inflatable truss is fastened into the mentioned structure along symmetry axis.

EFFECT: simplicity of formation of shell structure rigidity, increase of assembly rate and decrease of ship weight is achieved.

4 cl, 14 dwg

Description

The invention relates to small-sized shipbuilding, in particular to small-sized inflatable vessels with an inflatable hull, mainly to tourist, pleasure, sports and for other purposes motor, rowing or sailing vessels, and special-purpose vessels and structures, such as rafts or inflatable transitions (ship bridges), as well as to the space industry, aircraft, automotive, mobile structures for the rapid deployment of the Ministry of Defense and the Ministry of Emergencies (hospitals, tents, hangars, other building structures).

Known inflatable motor small boats have a general construction principle.

The upper inflatable body, cylindrical or other U-shaped, closed in the stern with a transom or inflatable element or open, the inflatable body can be formed by two balloons inflated along the axis of symmetry, fixed to each other by a frame or bottom, or in another way. The bottom, which can be inflatable or rigid (RIB) of various materials, such as plastic, resins with reinforcement of various fabrics, fibers, threads or metal, or the body is made of wood. There are small vessels with a rigid hull, and an inflatable board is fixed in the upper part of the sides or around the perimeter, which serves as an additional means for the buoyancy of the vessel. Known vessels with bulwarks and catamaran vessels, which have a shell structure, stressed by excessive pressure of the working medium (air). Typically, these structures have a cylindrical elongated streamlined shape.

An inflatable bulwark is installed on the inflatable hull of the ship in order to protect the ship from splashes and waves during movement. The bulwark increases the longitudinal stiffness of the inflatable ship.

Catamarans are characterized by the fact that they have two floating formations (skegs) along the bottom, which are located symmetrically to each other and are equidistant from the axis of symmetry of the bottom to the right and left sides. Trimarans have a catamaran design, only along the axis of symmetry, longitudinally, another skeg is installed. Trimarans can carry more weight, but lose to catamarans in speed.

There are various options for boats, such as rafts or temporary inflatable crossings between vessels that require lateral and longitudinal stiffness.

A patent of the Russian Federation for utility model No. 99763 (filed July 1, 2010, published November 27, 2010) is known, where the role of skegs is played by inflatable balloons, whether or not closed, which are interconnected by a power frame, and small floats are attached to the main inflatable balloons to form a planing surface.

There is a patent of the Russian Federation for utility model No. 148315 (filed April 4, 2014, published December 10, 2014) in which the width of the skeleton sole is adjusted by means of the skeg cylinder, in which a partition is installed longitudinally, which fixes the height of the skeg cylinder, and the width of two lobes formed by the partition a single cylinder is set depending on the required width of the sole of the skeg.

However, the above constructions have a number of significant limitations.

Somehow the inflatable body has a cylindrical U-shaped or other shape, which bears large longitudinal and transverse loads. The hull consists of a cylinder, usually of a cylindrical shape, in which, if necessary, there are sealed transverse bulkheads on the right and left sides, which create independent compartments that increase the survivability of the vessel. When one section is destroyed, at least one or two sections remain intact, in some cases there are more sections.

Transverse stiffness can be achieved if at least one inflatable element is installed across.

However, inflatable vessels have a weak point in longitudinal rigidity. If the weight in the cockpit of the vessel is not evenly distributed, for example, in the bow and stern, the inflatable hull bends and the ship loses its driving performance. In ships where wooden shale (flooring) is used in the cockpit, the rigidity is partially solved, but not completely, and the court with floorboards is less mobile, require additional assembly efforts, and the weight increases significantly. In vessels with an inflatable bottom, rigidity can be achieved if a rigid longitudinal frame frame is installed around the perimeter in the cockpit. The frame itself is overweight, requires enough time for assembly, has uncomfortable dimensions.

In small-sized inflatable vessels of the catamaran and trimaran type, inflatable formations (skegs) provide partially longitudinal stiffness, and if a bulwark is attached to such vessels, the vessel acquires additional rigidity.

Inflatable rafts have many design options, but everyone has a common feature. An inflatable raft has sections formed by internal partitions fixed to the inner surfaces of the shell structure, which create a three-dimensional mat, or sections consist of inflatable cylinders of cylindrical shape fastened alternately to each other. The same method is used to make ship bridge bridges. All of these structures require lateral and longitudinal rigidity.

In the aircraft industry, the design of the inflatable wing and body, as well as the use of inflatable skegs of the chassis, all of them need longitudinal rigidity.

In the automotive industry there is a category of motor vehicles in which volumetric wheels are used, this torus shell construction requires additional rigidity.

Large and small rapidly deployed premises used by the Ministry of Defense and Emergencies in the space industry also require rigid inflatable structures, such as masts for radio antennas, solar sails, planes for solar panels, inflatable transitions, etc.

In the construction of hangars, stadiums, skating rinks, warehouses, inflatable jacks, additional rigidity is required.

The publishing house of the Irkutsk State Technical University in 2006, published a monograph, "Elastic Mechanisms and Structures." The authors of the book V.N. Shikhirin, V.F. Ionova, O.V. Shalnev, V.I. Kotlyarenko. The book may be useful to students, graduate students, researchers and engineers involved in the design, operation of elastic mechanisms, rescue and engineering equipment and the study of their properties. The book sets out many years of experience in the creation and study of soft shells, flexible pneumatic structures, soft structural materials and so-called torus technologies and the prospects for their use in industry.

Elastic mechanisms (mechanisms with elastic elements) include soft, prestressed overpressure of the working medium, shell structures.

The monograph describes closed bubble systems that are close to solving the problem of creating an upper inflatable body resilient and rigid. However, such a system does not completely solve the task.

The elasticity for inflatable ships is necessary for compact assembly, the rigidity of the hull is necessary for driving characteristics during operation.

This monograph is a scientific description of soft shells and their mechanical capabilities, and with respect to the proposed solution has common features, namely the shell structure, stressed by overpressure of the working medium.

The design proposed in this application has the sufficient technical simplicity of forming the rigidity of the shell structure, which is stressed by the overpressure of the working medium, reduces the cost of the production process of rigidity of the inflatable hull, increases the speed of assembly and reduces the weight of the vessel. The listed advantages are the technical result of the proposed solution.

The applicant has conducted a patent search on this topic. He showed that the proposed combination of essential features was not found. Therefore, this invention can be considered a new invention.

The essence of the invention and its practical performance is illustrated by the drawings and the following description.

Rigid structures are known, such as flat trusses, consisting of lower and upper belts, forming the contour of the truss and a lattice consisting of braces and struts. Such rigid structures are made of metals, concrete, wood, plastic and other hard materials.

Truss belts work on longitudinal efforts, the lattice of farms perceives lateral loading. If all the rods are on the same plane, the truss is called flat. If the flat trusses are interconnected, a spatial truss appears with two or more faces.

On the Internet at the website http://window.edu.ru/resource/250/65250/files/ystu04.pdf, a textbook for students “Metal Structures” was published, which describes structures and their properties in detail.

The structural elements discussed below are trusses that can be flat and spatial and that are shell structure elements (see Wikipedia: A truss is a rigid structure made of straight rods connected at their ends by hinges. If all the truss rods are in the same plane , the truss is called flat. The joints of the truss rods are called nodes. All external loads are applied to the truss only at the nodes. When calculating the truss by friction in the knots and the weight of the rods (compared to the external loads) neglect or distribute the weights of the rods over the nodes. Then, two forces applied to its ends will act on each of the rods of the truss, which at equilibrium can be directed only along the rod. Therefore, we can assume that the truss rods work only in tension or on compression;

(фр.

, от лат.

прочный) - стержневая система в строительной механике, остающаяся геометрически неизменяемой после замены ее жестких узлов шарнирными. В элементах фермы, при отсутствии расцентровки стержней и вне узловой нагрузки, возникают только усилия растяжения-сжатия. Фермы образуются из прямолинейных стержней, соединенных в узлах).See Wikipedia.

(fr.

, from lat.

durable) - the core system in structural mechanics, which remains geometrically unchanged after replacing its rigid nodes with articulated ones. In the elements of the farm, in the absence of alignment of the rods and outside the nodal load, only tensile-compression forces arise. Farms are formed from rectilinear rods connected in nodes).

The farm consists of elements: a belt, a rack, a brace, a sprengel (a brace).

Spatial trusses form a rigid spatial beam, able to absorb the load acting in any direction. Each face of such a bar is a flat truss).

The present invention proposed the construction of various inflatable farms, prestressed by excessive pressure of the working medium, placed in shell structures.

The essence of the proposed method can be characterized as follows.

The method of reinforcing inflatable structures, including a shell structure, stressed by the overpressure of the working medium, characterized in that an inflatable flat truss formed from two zones, inflatable cylindrical cylinders and braces, an inflatable cylinder, which is fixed on the belt, is fixed in it along the axis of symmetry.

The method of reinforcing inflatable structures, including a shell structure, stressed by the overpressure of the working medium, characterized in that an inflatable structure of a continuous flat truss is fixed in it along the axis of symmetry.

The method of reinforcing inflatable structures, including a shell structure, strained with excess pressure of the working medium, characterized in that an inflatable structure of a continuous truss consisting of a two-layer elastic material is fixed along the axis of symmetry, polyamide yarns are woven between the layers, while both layers of elastic fabric around the perimeter their free edges are hermetically fixed to each other.

A method of reinforcing inflatable structures, including a shell structure, stressed by excessive pressure of the working medium, characterized in that a spatial inflatable truss is fixed along it on the axis of symmetry.

The inflatable cylindrical hull of a small vessel carries transverse loads, i.e. for compression and tension. The longer the inflatable hull, the smaller loads it can bear, with increasing loads it bends, thereby deforming the hull consisting of an inflatable hull and the bottom of the vessel. Theoretically, if an overpressure of 1-6 atmospheres was created, the inflatable hull could meet the technical characteristics of a rigid small-sized vessel made of metal, plastic, wood or other hard materials. But since inflatable small boats are made of elastic materials and have joint seams, then if not the elastic fabric itself, then the joint seams do not withstand the necessary pressure and loads. Currently, no technology is known that creates seamless inflatable ships.

A flat inflatable truss having inflatable braces is equal in characteristics to a continuous inflatable volumetric flat truss from the same elastic material, the only difference is that a continuous surface is simpler and cheaper to manufacture.

Elastic fabrics consist of an elastic material, which can be made of reinforcing fabric, which is coated on both sides with an airtight protective layer of polyvinyl chloride (PVC) polymer. The reinforcing layer holds the shape and the load, while the polymer protects the fabric from abrasion, laceration, ultraviolet radiation, aggressive chemical environment and is airtight. Depending on the thickness of the polymer layers and the thickness of the weaving threads of the reinforcing fabric, the material may be lighter or heavier in density g / cm 2. Depending on the size of the small vessel, fabrics of different densities are used to create it.

It is proposed (Fig. 1) in a shell structure 1, which is stressed by the overpressure of the working medium in which transverse and longitudinal stiffness is required, to install an inflatable truss 5 from elastic fabric on the axis of symmetry, which will take the proper shape and stiffness with excess air pressure. The farm is made of two belts 3 - inflatable cylindrical cylinders, and braces 4 - an inflatable cylinder, which is fixed between the two belts in such a way that on the inflatable belts the points of joining of the braces are marked, and the inflatable cylinder is marked out into equal segments that will serve as braces and for marking fixed to the belt; if necessary, inflatable racks can be installed 2. After applying excess pressure to the belts and the inflatable cylinder, the latter breaks down at points fixed on the belts. Thus, we get an inflatable farm 5, stressed by excess air pressure. Together with an inflatable balloon and an inflatable truss fixed from the inside, the hull will gain rigidity sufficient to withstand lateral loads. Braces can be made not only from a continuous long inflatable cylinder, but also from separate independent cylinders of the required length. In this case, each cylinder must have an air valve fixed to the shell structure, or have a more complex air duct structure.

It is proposed (Fig. 2) in the shell structure 1, tensioned by the excess pressure of the working medium along the axis of symmetry to install from an elastic fabric an inflatable structure of a continuous flat truss 6, which will take the appropriate shape and stiffness with excess air pressure.

A solid truss is made of elastic material and has two surfaces cut out in the shape of a rectangle or trapezoid or other shape, which repeats the contour of a section of the shell structure along the axis of symmetry. Two surfaces around the perimeter are hermetically fixed to each other and have internal partitions between them, which are fixed along their two free edges or around the perimeter (Fig. 4) along the axis of symmetry 8 or (Fig. 5) across 9 or (Fig. 6) are fixed under angle of 10 axis of symmetry as braces along the entire length of a continuous truss and form triangular or rectangular, or longitudinal, or transverse stressed volume sections. The thickness of a continuous flat truss can depend on the width of the partition, and the length and height can depend on the cut of the elastic material forming a three-dimensional figure of the inflatable truss.

Known elastic fabric (Fig. 7), consisting of two surfaces 11, it can be made of reinforcing fabric. Two surfaces on the outside are covered with an airtight protective layer of polymer, for example, polyvinyl chloride - PVC. The reinforcing fabric holds its shape and loads, while the polymer protects the fabric from abrasion, laceration, ultraviolet radiation, aggressive chemical environment and is airtight. Two layers of elastic fabric on the inside are woven with durable polyester yarn 12. The threads are located at a small distance of 1 cm ² , their number can reach 20-40 pcs. If two layers of elastic fabric around the perimeter of their free edges are hermetically fixed to each other and tension is created by excessive pressure of the working medium, the design will take the form of a volume mat. The thickness of the mat will depend on the length of the threads that weave the two surfaces of the elastic fabric. Due to the strength of the polyamide yarns and their frequent location on the inner surfaces of the elastic fabric, the structure can withstand large internal pressure. If you create a bulk mat (Fig. 3) from a fabric in the form of a continuous flat truss 7 and give an excess pressure of 0.5 to 1 atmosphere, the design will have excellent stiffness characteristics in a working, stressed state and have good elasticity in a non-working state.

It is also proposed (Fig. 3) to enclose the inflatable structure of the continuous truss 7. in the shell structure 1, stressed by the excess pressure of the working medium, along the axis of symmetry. The truss (Fig. 7) consists of a two-layer elastic material 11, between which polyamide yarns 12 are woven. in shape, where necessary, coinciding with the outline of the line of the longitudinal tear in the diametrical plane of the body. Two layers of elastic fabric around the perimeter of their free edges are hermetically fixed to each other, and when voltage is created by excessive pressure of the working medium, the inflatable structure will take the form of a continuous flat truss.

The inflatable design of a flat truss made of two-layer material interconnected by polyamide yarns is the most rigid of flat inflatable trusses. But two-layer fabrics are quite expensive, and the manufacture of mats has a very complicated production for creating tight seams that can withstand high pressure for a long time.

The above methods are methods for creating flat farms. Spatial trusses (Fig. 14) form a rigid spatial beam 13, capable of absorbing loads acting in any direction. Each face of such a bar is a flat inflatable farm. A spatial truss can be created from two flat continuous or with braces of inflatable trusses in a cross section (Fig. 9) without the plane of the truss at the base, or any shape of the spatial truss (Fig. 8, 9, 10, 11, 12, 13) having any case of several faces. The spatial truss is fixed from the inside, along an axial cylindrical or otherwise shaped body (shell structure).

In the case of using truss structures in the manufacture of ship hulls, bulwarks, skegs, catamarans and trimarans, there is no need to produce inflatable hulls with hermetic sections, since the truss inside the hull plays the role of an additional guarantor of vessel buoyancy in case of violation of the tightness of the inflatable shell structure.

Claims (4)

1. A method of reinforcing inflatable structures, including a shell structure, stressed by overpressure of the working medium, characterized in that an inflatable flat truss formed from two zones, inflatable cylindrical cylinders and braces, an inflatable cylinder, which is fixed on the belt, is fixed in it along the axis of symmetry. 2. A method of reinforcing inflatable structures, including a shell structure, stressed by excess pressure of the working medium, characterized in that an inflatable structure of a continuous flat truss is fixed along it in the axis of symmetry. 3. A method of reinforcing inflatable structures, including a shell structure, stressed by excess pressure of the working medium, characterized in that an inflatable structure of a continuous truss consisting of a two-layer elastic material is fixed along the axis of symmetry, polyamide yarns are woven between the layers, both layers of elastic fabric along the perimeter of their free edges are hermetically fixed to each other. 4. A method of reinforcing inflatable structures, including a shell structure, stressed by excess pressure of the working medium, characterized in that a spatial inflatable truss is fixed along the axis of symmetry therein.

Images