WO1997007028A1

WO1997007028A1 - Extensible and compressible hollow element

Info

Publication number: WO1997007028A1
Application number: PCT/FR1995/001092
Authority: WO
Inventors: Clair Costanzo; Laurent Freani; Robert Hugel
Original assignee: Clair Costanzo; Laurent Freani; Robert Hugel
Priority date: 1995-08-17
Filing date: 1995-08-17
Publication date: 1997-02-27
Also published as: AU3225795A; EP0808277A1; EP0808277B1

Abstract

Extensible and compressible hollow element (1) having a sidewall extending about the main axis (A) thereof and comprising one or more bellows type structures including two portions (9-12) with a peripheral length that increases progressively from a small common base connecting the two parts and forming an inner peripheral hinge (7, 8), to the end cross-sections (4, 5, 9) of the two portions forming the larger bases. The length of the generators (e, f) of the two cross-sections changes along the periphery of said sidewall, and parts or the whole of the two bellows portions may be of different lengths, so that the bellows portions may be of different lengths, so that the bellows is retained in a compressed position. The invention generally pertains to extensible and compressible hollow bodies, whether in the form of containers such as cans or bottles, or tubular elements such as pipes.

Description

COMPRESSIBLE AND EXTENSIBLE HOLLOW ELEMENT

The present invention relates to a compressible and extensible hollow element.

It generally relates to compressible and extensible hollow bodies, whether they are containers such as cans or bottles, or tubular elements such as pipes.

These hollow elements are made up of several sections, the side walls of which form one or more bellows allowing their compression and extension. Examples of such blow molded articles from plastics such as polyethylene or polyvinyl chloride can be found in US patent applications Nos. US 4,492,313 and US 4,773,458.

Each elementary bellows is generally formed by two opposite flared side wall portions (in the direction of the central axis, connected by their small bases thus constituting a fold playing the role of a circular internal hinge extendable radially. The large bases are each connected to the large base of one of the flared parts of an adjacent elementary bellows thus forming external circular hinges which can be extended radially, the two flared parts constituting an elementary bellows may be of the same width or of different widths. in this case, an eccentricity occurs during compression which can cause the bellows to lock. Up to now, it has been considered that the generatrix of the flared parts should preferably have a constant length over the entire circumference, said generatrix being the line of intersection of the wall of a flared part with a plane parallel to the axis. main and perpendicular to this wall, the length of the generator corresponding to the length of this intersection between the small base and the large base of a flared part. However, this known solution is not optimal in all cases, in particular for hollow bodies not having a circular section at any point on the main axis.

The invention aims to remedy these drawbacks, by dispensing with the need for a constant dimension of the side walls of the bellows. On the contrary, the applicants have discovered that the variation in the length of the generators along the circumference of the flared parts forming the bellows could have very interesting advantages. Indeed, this feature makes it possible to considerably increase the field of application of compressible and extensible hollow elements, in particular for hollow articles not having a circular cross section at all points of their length.

The present invention describes a compressible and extensible hollow element comprising a side wall extending around the main axis of the element and comprising at least one bellows-type structure composed of two parts whose length of the periphery gradually increases from from a small common base joining the two parts and constituting an internal peripheral hinge, up to the terminal cross sections of the two parts forming the large bases, the length of the generators of these two sections being variable along the periphery of said side wall.

In certain hollow body applications according to the invention, the terminal cross sections of the two flared parts are separated from each other, that is to say that the peripheral lines defining the large bases do not meet at any point. of the hollow element.

Advantageously, the shape of the peripheral internal "hinge" (small base) joining the two parts of a bellows will be different from the shape of the terminal cross sections (large bases). Preferably, the small base will have an annular or rounded shape, while the two opposite large bases will have a substantially polygonal shape. This combination of annular and polygonal shapes allows easier and more efficient storage of the hollow bodies, each element occupying less space, however, because of the annular shape, preferably substantially circular of the small base, any interference of the polygonal parts of the bellows with neighboring parts, during compression or extension of said bellows.

The bellows will advantageously be of the eccentric type, the generator of one of the flared part being smaller than the generator of the second flared part at each point of the periphery of the bellows.

For other applications, the two flared parts may each consist of two portions, the first being arranged in the extension of one another and having generators of substantially constant length, the generators second portions being curved and of different lengths so as to allow an eccentricity and a locking of the corresponding bellows, the curvature of the second portion being greater than that of the first. A compressible and extensible hollow body is thus obtained provided with a locking zone and the bending resistance of which is increased in a plane perpendicular to the main axis, due to the small angle formed by the first portion in this plane. This configuration is particularly advantageous for containers of large dimensions such as jerry cans.

In an alternative embodiment of a hollow body according to the invention, the length of the generatrices of the two flared parts varies, along the periphery, from zero, at one point of the side wall, to a maximum value at the opposite point. Thanks to this configuration, a variable compressibility of the hollow element is obtained from one side to the opposite side, the result of which is a curvature of the hollow element in line with the bellows concerned. This embodiment will advantageously be used for pouring tubes of cans or jerry cans.

The external walls will preferably comprise at least two contiguous bellows-type structures, the "internal peripheral hinges" (small bases) of which are spaced apart from each other, and the directions of extension of which are opposite, which allows bending of the hollow body, as well as a substantially rectilinear extension and compression in the direction of the central axis. The bellows will advantageously be of the eccentric type, the generator of one of the flared part being smaller than the generator of the second flared part at each point of the periphery of the bellows. In all cases, at least part of the "peripheral hinge" constituting the small common base of the two flared parts will preferably be formed by a recess opening towards the outside and constituting a peripheral channel, for example in the form of a U or V.

In the case described above, where the length of the generators of the two flared parts varies from zero to a maximum value, it is very advantageous to also vary the dimensions of the peripheral channel from zero to a maximum value in parallel with the increase in the length of the generators, which in addition facilitates the blow molding of the hollow body.

In the appended drawings, given by way of nonlimiting examples of preferred embodiments of the subject of the invention: FIG. 1 is an isometric view of a first alternative embodiment of the hollow element in the stretched position, FIG. 2 is an isometric view of the hollow element of FIG. 1 when it is compressed, FIG. 3 represents, seen from the side in elevation, a second variant of hollow element in the extended state, FIG. 4 is a horizontal cross section of the hollow element of FIG. 3, FIG. 5 is a partial view of the hollow element of FIG. 4 when it is compressed, FIG. 6 is a partial schematic view in elevation, of a third variant of hollow element showing, in the extended state, the pouring pipe of a jerry can, FIG. 7 is a schematic partial view of the hollow element of FIG. 6, in the state of compression and FIG. 8 represents, seen from the side in elevation, the jerry can equipped with the pouring hose of FIG. 6.

In FIGS. 1 and 2, a container 1 blow molded from plastic material such as polyethylene or polyvinyl chloride comprises an upper part 2, a base 3 and a side wall 17 extending around a central axis A. The upper part 2 and the base 3 have the shape of parallelepipeds defined respectively by an upper face 2 "square and sides 2 ', and a bottom 3" square and sides 3'. The upper face 2 "is open to facilitate access to the interior of the container 1 and can be closed by a suitable plug not shown here. The bottom 3" is closed.

The side walls 17 are composed of two bellows 17 'and 17 ", each of them comprising a flared upward part 9, 11, and a flared downward part 10 12, connected together by an inner circular hinge zone 7 , 8 in the shape of a U. This type of hinge zone is known in itself and has been the subject of an American patent application No. US 4,773,458.

The upwardly flared part 9 of the upper bellows 17 ′ is connected, at its end opposite to the circular hinge zone 7, at the lowest edge of the sides 2 ′ by an edge 6 forming a square and consisting of a peripheral fold of Wall. Likewise, the downwardly flared part 10 of the upper bellows 17 ′, and the upwardly flared part 11 of the lower bellows 17 "are connected together by their ends opposite respectively to the circular hinge zones 7, 8 by a peripheral edge 4 in the shape of a square. And finally, the flared part down 12 of the lower bellows 17 "is connected, at its end opposite to the hinge zone circular 8, at the upper edge of the sides 3 ′ by a square peripheral edge 5.

The angles of the edges 4, 5 and 6, of the base 3 and of the upper part 2 can be rounded. As we can see, each flared part 9,

10, 11, 12 has a square base and a circular top. Corner edges 13, 14, 15, 16 form the connections between the adjacent faces of said flared parts and are less and less accentuated as one approaches the circular hinge zones 7 and 8.

In container 1, at each point of the circumference, the length of the walls of the downward flared parts 10 and 12, measured along their intersection with a plane passing through the central axis A, is greater than that of the walls upwardly flared portions 9 and 11, measured in the same manner.

It follows that the angle α between the above intersection lines of the walls 9 and 11 with a plane perpendicular to the central axis A is greater than the angle β between the intersection lines of the walls 10 and 11 and the same plane perpendicular to the central axis A.

The angles α and β have an increasing value from an angle edge 13, 14, 15, 16 and an intermediate point between two of these angle edges. Similarly, the length of the generators gradually decreases from a value (g, h) measured at the corner edge to a value (e, f) corresponding to a point equidistant from two corner edges.

The bellows 17 ', 17 "are of the eccentric type, which means that, during compression (Figure 2), the external edges pass below the internal edges. The bellows are preferably self-locking so as not to return to their uncompressed state in the absence of an external force. Compared to a container similar to container 1 also comprising a polygonal contour, but whose internal hinge zones are square instead of being circular, the internal and external parts of the bellows present less risk of interference during extension or compression.

The container 101 shown in Figures 3, 4 and 5 is formed by a base 104, a side wall 102 consisting of bellows extending around the central axis B, and an upper part 103 having an opening closable by a plug 105 and a handle 106. The side wall comprises three complete bellows 102 ', 102 "and 102"', as well as an upper half-bellows 107 'consisting of a part flared downwards. Each bellows 102 ', 102 "and 102"' is formed by a portion of wall flared up 108 and a portion of wall flared 107 connected to the previous one by an internal peripheral hinge zone 110 in the form of U. The bellows 102 ', 102 "and 102"' are connected to each other, as well as with the half-bellows 107 'and the base 104 by foldable zones forming peripheral edges 109.

The container 101 is made of blow molded polyethylene or polyvinyl chloride. As can be seen in Figures 3 and 4 the flared parts 107 and 108 have a width varying along the periphery of the side wall. In the zones 111 and 112 situated at the front and at the rear of the flared parts 107 and 108 respectively, the width c of the flared part 107 is greater than the width d of the flared part 108 making it possible to block the bellows in these zones, said width being equal to the local length of the generatrix of the wall of the flared part considered. In zones 113 and 114 located on the sides of parts 107 and 108 respectively, the width a of the part 107 is equal to the width b of the part 108.

Between zones 112 and 114, as well as 111 and 113, along the periphery, the width c gradually decreases towards the width a, while the width d increases towards the width b. Since in zones 113 and 114 the width a and b of the flared parts 107 and 108 are equal, there will be no eccentricity of the bellows at the location of these zones during the compression of the container, the zones 113 and 114 being simply applied one against the other and superimposed. On the other hand, the zones 111 and 112 will be off-center and blocked during the compression of the container 101. As a result, the latter can be kept in the compressed state as seen in FIG. 5, while the side wall will have a large resistance to deformation forces caused by the contents of the container.

In FIGS. 6, 7 and 8 we can see a container 201 of the jerry can type, with a handle 206 and a pouring pipe 203 comprising a neck 204 provided with a threaded opening 205 intended to receive a stopper (not shown), and a tubular part consisting of a wall 202 extending around a central axis C and formed of a series of bellows 202 ′ to 202 ^v between the upper part 212 of the container and the shoulder 211 of the neck 204. The pouring pipe may be made for example of polyethylene or polyvinyl chloride blow molded. Each bellows 202 ′ to 202 ^v comprises a wall part flared upwards 207 and a wall part flared downwards 208 connected together by hinge areas 209 in a U shape. The bellows are connected to one another as well as '' in parts 211 and 212 by external edges 210 formed by peripheral folds of the side wall.

This embodiment has a remarkable feature. Indeed, the flared parts 207 and 208 are tapered between two opposite sides of the wall 202 of the pouring pipe. As can be seen in Figures 6 to 8, the heights of the flared parts 207, 208 have values i, j on one side, values k, 1 at a point between the two sides and are practically zero on the side opposite. The direction of this transverse taper is reversed from a bellows to the adjacent bellows and so on. As a result, two contiguous bellows are located between two parallel external edges 210.

In FIGS. 6, 7 and 8, the height of the flared part 208 has a maximum value greater than the width of the flared part 207, which allows eccentricity of the bellows during the compression of the pipe 203. The compression of the pouring pipe 203 can be carried out step by step, the inclination of the opening of the pouring pipe being modified with each step, which gives the user many possible positions of the opening of the pouring pipe. In FIG. 6, it can be noted that the dimension of the hinge areas 209 in the shape of a U, the size of which gradually decreases to be zero at the crossing of two adjacent external edges 210, to the point where the heights of two flared parts 207 and 208 are also zero. Consequently, the depth / width ratio of the U-shaped hinge zone varies along the periphery, which has, among other things, the advantage of facilitating molding.

The positioning of the various constituent elements gives the object of the invention a maximum useful effects which had not, to date, been obtained by similar devices.

Claims

1 °. Compressible and extensible hollow element (1 - 101 - 202), usable for the production of various compressible, extensible and possibly bendable hollow bodies, whether they are containers (1 - 201) such as cans or bottles, or tubular elements (202) such as pipes, having a side wall extending around the main axis (A - B - C) of the element and comprising at least one bellows-type structure composed of two flared parts (9 to 12 - 107 and 108 - 207 and 208) whose length of the periphery gradually increases from a small common base joining the two flared parts and constituting an internal peripheral hinge (7, 8 - 110 - 209), up to end cross sections forming the large bases of these two flared parts, and consisting of peripheral edges (4 to 6 - 109 - 210) made up of foldable zones of the side wall, characterized in that the length of the generatrices of the two flared parts constituting a bellows is variable along the periphery of said side wall, this generatrix being the line of intersection of the wall of a flared part with a plane parallel to the main axis (A - B - C) and perpendicular to this wall, the length of the generator corresponding to the length of this intersection between the small base and the large base of a flared part (9 to 12 - 107, 108 - 207, 208).

2 °. Hollow element according to claim 1, characterized in that the generator of one of the flared part (10, 12 - 107 - 207) is smaller than the generator of the second flared part (9, 11 - 108 - 208) of a bellows at each point of the periphery thereof.

3 °. Hollow element according to any one of the preceding claims, characterized in that the flared parts (207, 208) are tapered transversely between two opposite sides of the side wall (202), the length (i, j, k, 1 ) generators of said flared portions varying, along the periphery, from a zero value, at a point of the side wall, to a maximum value at the opposite point.

4 °. Hollow element according to claim 3, characterized in that it comprises at least two bellows and that the direction of the transverse tapering of the flared parts (207, 208) is reversed from one bellows to the adjacent bellows, so as to that two contiguous bellows are situated between two parallel external peripheral edges (210).

5 °. Hollow element according to any one of the preceding claims, characterized in that at least part of the internal peripheral hinge (7, 8 - 110 - 209) constituting the small common base of the two flared parts (9 to 12 - 107 and 108 - 207 and 208) is formed of a recess opening towards the outside and constituting a peripheral channel, for example in the form of U or V.

6 °. Hollow element according to claim 5, characterized in that the section of the peripheral channel is U-shaped.

7 °. Hollow element according to claims 3, 4 and 6, characterized in that the size of the peripheral channel gradually decreases to be zero at the crossing of two adjacent external edges (210), to the point where the heights of two flared parts (207, 208) are also zero.

8 °. Hollow element according to either of Claims 1 and 2, characterized in that the internal peripheral hinge (7, 8) joining the two flared parts of a bellows has an annular or rounded shape, while the peripheral edges ( 4, 5, 6) formed by terminal cross sections have a substantially polygonal shape.

9 °. Hollow element according to either of Claims 1 and 2, characterized in that the sections of the peripheral edges (4 to 6 - 109) formed by end cross sections of the two flared parts (9 to 12 - 107 and 108) are separated from each other, that is to say that they do not meet at any point of said hollow element.

10 °. Hollow element according to any one of claims 1 and 2, characterized in that the two flared parts constituting a bellows each consist of two portions, the first being arranged in the extension of one another and having generators of substantially constant length, the generators of the second portions being curved and of different lengths so as to allow an eccentricity and a locking of the corresponding bellows, the curvature of the second portion being greater, greater than that of the first.