FR2776751A1 - POLYEDRIC TANK INCORPORATING STRAINERS FOR CONTAINING PRESSURIZED FLUIDS - Google Patents

Abstract

The invention concerns a polyhedral tank having a substantially parallelepiped shape internally and externally designed to contain fluid under pressure, comprising a shell and internal reinforcing elements arranged inside the shell, mutually parallel and substantially perpendicular to the shell internal surfaces. The reinforcing elements (2) consist of sheet metal plates comprising at least one aperture (5). The invention is applicable to motor cars operating with LPG.

Description

The technical sector of the present invention is that of tanks

  intended to contain pressurized fluids, such as tanks subjected to internal pressure, and more particularly liquefied petroleum gas tanks, called LPG for vehicles. Generally, the tanks intended to contain pressurized fluids consist of an envelope of metallic material in sheet form to obtain a substantially cylindrical assembly the ends of which are in the form of a portion of a sphere. This shape is well suited to evenly distribute stresses

on the periphery of the tank.

  LPG tanks used for example in cars are generally cylindrical or toric,

  conventionally metallic and preferably steel.

  The toroidal tanks are mounted at the location of the spare tire. Their capacity is limited due to

  lack of space available at this location.

  The cylindrical tanks are generally arranged at the bottom of the trunk, where they considerably reduce the volume of the latter, all the more since the compartment which is intended to accommodate them is parallelepipedic and that the volume between the corners of the compartment and the arc of the tank is empty. This results in a loss of

  useful volume, both for the trunk and for the tank.

  Cylindrical tanks can also be mounted under the rear overhang trunk. The available space is limited in height, which requires the use of a small diameter cylindrical tank, or several small diameter cylindrical tanks connected together by a pipe welded radially on the periphery of the cylinders. This solution, if it makes it possible to obtain a large volume without encroaching on the volume of the trunk, is nevertheless expensive and does not allow optimal use of the volume available under the trunk, since there is always an empty part between the two adjoining cylindrical tanks. Finally, it should be noted that the toric and cylindrical tanks are often integrated in compartments of parallelepiped shape, which prohibits optimal use of the available space. We have tried to overcome these drawbacks by proposing parallelepiped tanks. However, their shape presupposes edges which are conducive to breaking points and they have the disadvantage, compared to cylindrical or toric tanks of the same capacity and of the same mechanical strength, of being much heavier, because thicker walls have to be provided. . In addition, the reservoir does not deform homogeneously over its entire periphery and the edges constitute zones of compound stress o the

  constraint is applied multidirectionally.

  The object of the present invention is to provide a tank having an external shape capable of being housed in automobile compartments with parallelepiped shapes, while being light, and having good mechanical characteristics to resist pressure

  internal generated by the pressurized fluid.

  The present invention therefore relates to a polyhedral reservoir of external and internal shape substantially parallelepiped intended to contain pressurized fluid, characterized in that it comprises an envelope and internal reinforcements arranged inside the envelope, parallel to the to each other and substantially

  perpendicular to the inner faces of the envelope.

  Reinforcements are sheet metal plates

including at least one day.

  The day has a rectangular or triangular shape with rounded corners, or a circular shape. The reinforcements are constituted by substantially tubular metallic elements comprising days and the ends of which terminate in a corolla delimiting

  petals flared at their bases. The section of said element is circular or polyhedral.

  The invention also relates to a polyhedral reservoir of exterior and interior shape substantially parallelepiped intended to contain fluid under

  pressure, characterized in that it comprises an envelope and internal reinforcements superimposed in successive layers integral with the walls and the layer or layers located immediately above and / or below.

  Advantageously, two successive layers of internal reinforcements are arranged alternately in directions

substantially perpendicular.

  The internal reinforcements are in the form of

sheet metal folded into slots.

  The internal reinforcements are in the form of

  sheet folded in triangle, arranged alternately head to tail.

  The internal reinforcements are in the form of

  sheet bent in alternating semicircles.

  One of the walls of the envelope is in the form

of corrugated iron.

  The reinforcement support points are arranged at the

  level of the junction of two adjacent undulations.

  The undulations are in the form of arches.

  The undulations have a triangular shape.

  An advantage of the reservoir according to the invention consists in the fact that its envelope can comprise angular parts and can occupy all the available space offered by a receiving compartment comprising shapes composed by the parallelepipeds therefore having sharp angles. Another advantage of the reservoir according to the invention consists in the fact that the reinforcements which constitute it prevent the walls of the envelope from deforming under

the effect of internal pressure.

  Other characteristics, details and advantages of the invention will appear more clearly on reading the

  additional description which follows modes of

  embodiment given by way of example in relation to the drawings in which: - Figure 1 is a three-dimensional view with a cross section of a tank according to the invention, - Figure 2 is a three-dimensional view of a cross-section of another embodiment of the reservoir according to the invention, - Figure 3 is a three-dimensional view of a reinforcement of cylindrical shape, - Figure 4 is a three-dimensional view of a

  reinforcement with crimped corrugation in the form of slots.

  - Figure 5 is a longitudinal sectional view of a section of a tank comprising a wall in the form of corrugated sheet. In Figure 1, there is shown a reservoir according to the invention, the envelope 1 is a substantially parallelepiped polyhedron comprising reinforcements 2. These reinforcements 2 are arranged parallel to each other and perpendicular to the walls of the envelope 1. These reinforcements 2 consist of sheet metal plates and preferably of steel plates. They are fixed to the walls of the envelope by any welding means with or without the addition of metal. They are preferably welded by transparency, that is to say by laser welding. These reinforcements occupy the entire height and the entire width available inside the envelope in order to obtain maximum inertia in the available volume. Each of the reinforcements 2 comprises a lower part 3 and an upper part 4, the lower part 3 being wider than the upper part 4. The upper part 4 of the reinforcement comprises several days 5 of triangular shapes arranged linearly along said upper part 4 The triangles that make up the 5 days have rounded corners and are arranged so that their vertices are alternately directed upwards then downwards. The angles of the triangles are rounded to avoid incipient fractures. In the lower part 3 of the reinforcement, there were also 5 days 5 of triangular shapes with rounded angles, but of larger size, and these are also arranged so that their vertices are alternately directed upwards then towards the bottom. In order to consolidate the structure of the reservoir, it is possible to connect the reinforcements two by two by a metal plate 6 in sheet form, preferably in steel, in which a day of substantially rectangular shape 7 has been made. This plate 6 which marks the limit between the upper part 4 and the lower part 3 will always be preferably welded by transparency perpendicular to the

  reinforcements and perpendicular to the walls of the envelope 1.

  Another embodiment of the reinforcements according to the invention is shown in Figure 2. It is a reinforcement in the form of sheet metal, preferably steel, whose 5 days are of substantially rectangular shape. Unlike the reinforcements 2 perforated by triangle, the reinforcement 8 shown in Figure 2 does not occupy all the available height. In this nonlimiting exemplary embodiment, the reinforcement comprises two main days 5a and 5b located in the middle part of the reinforcement. These days have a substantially rectangular shape with rounded angles in order to avoid the beginnings of rupture. Above these main days 5a and 5b, there are two other days 5c and 5d of more modest size also of substantially rectangular shape with rounded angles and below these main days, there is also another day 5e of rectangular shape at the angles rounded. The distance separating the main days 5a and 5b is substantially equal to the distance separating the two upper secondary days 5c and 5d thus forming a solid metal strip in the middle part of the reinforcement. Furthermore, the main day 5b is equidistant from the secondary days 5d and 5e. The ends of the laminated metal plate which constitutes the reinforcement 8 terminate in lugs 9 of different widths and of different lengths according to the stresses which the walls undergo. These tabs 9 are welded to the walls of the casing 1 by any welding means with or without the addition of metal. They are preferably welded by transparency, that is to say by laser welding. These tabs 9 have their ends 10 slightly wider than their body in order to increase the inertia of the assembly after welding. The days 11 that these tabs create after welding on the walls of the tank also have a substantially rectangular shape with rounded corners. Days 11 are preferably located at each of the angles formed by two successive walls of the tank 1. In order to consolidate the structure of the tank, it is possible to connect the reinforcements two by two by a sheet of laminated metal, preferably steel, in which one day of substantially rectangular shape was practiced. This plate will always be preferably welded by transparency along a median strip M, that is to say between days 5a and 5b and days 5c, 5d and 5e, perpendicular to the reinforcements and

  perpendicular to the top wall of the tank 1.

  Another embodiment of a reinforcement according to the invention can be implemented. It is a reinforcement in the form of sheet metal, preferably steel, the days of which are substantially circular in shape. This type of reinforcement has the same structure as that of the reinforcement shown in Figure 2 and the days are arranged in substantially the same manner as in the mode of

previous achievement.

  Another embodiment of the reinforcements according to the invention is shown in Figure 3. This reinforcement 12 is in the form of a cylindrical tube which is fixed between two opposite walls of the shell of the tank by any means of welding with or without adding metal. However, on -7 prefers transparent welding, that is to say by laser welding. The positioning of these reinforcements 12 in the reservoir 1 is done according to the constraints which the reservoir undergoes due to the pressurized fluid which it contains. However, this type of reinforcement 12 is more particularly suitable for reservoirs of low height. This reinforcement 12 is a circular cross-section tube in which days 13 have been made, approximately four in number, parallel to the axis of the tube. The days practiced are of substantially rectangular shape with rounded corners always in order to avoid the incipient fractures and they face two by two along the axis of the tube. The ends 14 of the tube are in the form of corollas comprising approximately four petals 15 flared at their bases, the ends of which form a plane parallel to the wall of the reservoir in order to increase the contact surface with said wall, thereby increasing the weld inertia. Obviously, the ends 14 in the shape of a corolla can delimit a

larger number of petals 15.

  Furthermore, in an equivalent embodiment, the section of the tube can be polyhedral; then, each of the faces of the polyhedral section tube may have a day of rectangular shape with rounded angles along the axis of the tube and the upper and lower ends of each of the faces may have a petal with a flared base, the ends of which form a plane parallel to the inner wall

of the tank.

  Another embodiment of the reinforcement according to the invention is shown in Figure 4. It is a metal sheet reinforcement, preferably steel, whose general structure is cross-corrugated. This reinforcement 16 comprises at least two parts, an upper and another lower, of substantially identical shape. In this embodiment, each laminated metal plate has been shaped to obtain a corrugation in the form of slots. These slots have a low height, around 30 mm, which will allow the entire structure to have good inertia. The upper part 16a of this reinforcement is arranged in a direction substantially perpendicular to the direction of the lower part 16b and it will preferably be welded by transparency to the said lower part. Due to the shape of the slots, the contact surface between the upper part and the lower part of the cross-corrugation reinforcement is large, which provides great inertia to the weld. Furthermore, the angles formed by the successive sides of the slots will preferably be rounded. The cross-corrugated reinforcement is secured to the reservoir 1 by any welding means with or without the addition of metal, but it will preferably be welded by transparency, either at its lower part, or at its upper part or at both . It should be noted that the corrugation can be obtained by a sheet folded in the form of triangles arranged alternately head to tail or else in sheet folded in the form of alternating semicircles. Another embodiment of a tank according to the invention is shown in Figure 5 which shows a longitudinal sectional view of a section of a tank. The reservoir shown is polyhedral with a substantially parallelepiped shape. It comprises at least one wall in the form of corrugated sheet and internal reinforcements 2 arranged parallel to one another and

  perpendicular to the walls of the shell of the tank.

  These reinforcements 2 are in the form of substantially flat plates. The ripple of the wall is formed by the succession of arches 17 whose radius of curvature of each of them varies according to the stresses undergone by the wall of the reservoir due to the pressurized fluid which it contains. The undulation of the wall may not be uniform, that is to say that the radii of curvature of two successive arches 17 may be different. Each of the arches 17 which form the wall of the tank is located between the support points of the reinforcements 2, that is to say that the intersection of two successive arches 17 form an edge which corresponds precisely to the end of a reinforcement 2. The edges formed by two successive arches 17 will be welded by any welding means with or without the addition of metal, preferably by transparency, along the upper part of each reinforcement 2. The reinforcements 2 may be of any shape and preferably openwork shape by triangle or rectangle as described in the paragraphs

previous.

  However, these types of tanks can find applications on all the hollow bodies, of form "not of revolution", subjected to an internal pressure like for example

  in the field of hydraulic accumulators.

Claims (10)

  1 - Polyhedral reservoir of substantially parallelepipedic external and internal shape intended to contain pressurized fluid, characterized in that it comprises an envelope (1) and internal reinforcements (2) arranged inside the envelope, in parallel with the relative to each other and substantially perpendicular to the faces internal envelope.   2 - Tank according to claim 1, characterized in that the reinforcements (2) are sheet metal plates comprising at least one day (5).   3 - Tank according to claim 2, characterized in that the day has a rectangular or triangular shape whose angles are rounded, or a shape circular.   4 - Tank according to claim 1, characterized in that the reinforcements (12) are constituted by substantially tubular metallic elements comprising days (13) and whose ends (14) end in corolla   delimiting petals (15) flared at their bases.   - Tank according to claim 4, characterized in that the section of said elements (12) is circular or polyhedral. 6 - Polyhedral reservoir of substantially parallelepipedal exterior and interior shape intended to contain pressurized fluid, characterized in that it comprises an envelope (1) and internal reinforcements (16) superimposed in successive layers (16a, 16b) integral with the walls and the layer (s) immediately above and / or at the below.   7 - Tank according to claim 6, characterized in that two successive layers (16a, 16b) of internal reinforcements are arranged alternately in directions substantially perpendicular.   8 - Tank according to claim 7, characterized in that the internal reinforcements (16) is in the form of sheet metal folded into slots.   9 - Tank according to claim 6, characterized in that the internal reinforcements (16) are in the form of sheet folded in a triangle, arranged alternately head to tail. - Tank according to claim 6, characterized in that the internal reinforcements (16) are in the form   of sheet metal folded in alternating semicircles.   11 - Tank according to any one of   Claims 1 to 10, characterized in that at least one of   walls of the envelope is in the form of a corrugated sheet. 12 Tank according to claim 11, characterized in that the support points of the reinforcements (2) are arranged   at the junction of two adjacent undulations.   13 - Tank according to claims 11 and 12,   characterized in that said undulations (17) are in form of arches.   14 - Tank according to claims 11 and 12,   characterized in that said undulations (17) have a triangular shape.