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Title:
DOUBLE SEAMING ARRANGEMENT AND DOUBLE SEAMING PROCESS FOR RECIPIENTS
Document Type and Number:
WIPO Patent Application WO/2009/018636
Kind Code:
A1
Abstract:
The arrangement is applied to recipients comprising a tubular body (10) having an end edge (10a) which incorporates an outer flange (11) forming a first and a second hook (12, 13). An end wall (20) incorporates a closure flange (21) forming an outer hook (22) and a median hook (23) which have their inner surfaces seated onto the first and the second hook (12, 13), and an inner hook (24) being internal to the first hook (12), and seated, on one side, against the tubular body (10) and/or the side region of the first hook (12) and, on the other side, against a median side region of the first hook (12), a base portion (24a) of the inner hook (24) being spaced from a base portion (12a) of the first hook (12), the inner hook (24) and the second hook (13) presenting free end edges (24b, 13b) radially spaced from each other.

Inventors:
ALVARES ANTONIO CARLOS TEIXEIRA (BR)
CUNHA SILVERIO CANDIDO DA (BR)
Application Number:
PCT/BR2008/000229
Publication Date:
February 12, 2009
Filing Date:
August 01, 2008
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
BRASILATA EMBALAGENS METALICAS (BR)
ALVARES ANTONIO CARLOS TEIXEIR (BR)
CUNHA SILVERIO CANDIDO DA (BR)
International Classes:
B65D8/20; B21D51/26; B21D51/32
Foreign References:
EP0365063A11990-04-25
EP0281024A21988-09-07
US4089283A1978-05-16
GB2119342A1983-11-16
GB1325706A1973-08-08
Attorney, Agent or Firm:
ARNAUD, Antonio M.P. et al. (93 - 9th floor, -901 São Paulo - SP, BR)
Download PDF:
Claims:

CLAIMS

1. A double seaming arrangement for recipients which comprise a tubular body (10) having an end edge (10a) to which is double seamed a peripheral edge (20a) of an end wall (20) of the recipient, the end edge (10a) of the tubular body (10) incorporating an outer flange

(11) , which is bent toward the tubular body (10) , in order to form rounded U-shaped first and second hooks

(12, 13), which are turned to opposite axial directions, the peripheral edge (20a) of the end wall (20) incorporating a closure flange (21) which is bent to form an outer hook (22) , a median hook (23) and an inner hook (24) , which are all rounded U-shaped, said arrangement being characterized in that the outer hook (22) and the median hook (23) have their inner surfaces seated onto the whole extension of the first hook (12) and of the second hook (13) , respectively, said inner hook (24) being disposed in the interior of the first hook (12), so as to be externally seated, on one side, against at least one of the parts of tubular body (10) and side region of the first hook (12) and, on the other side, against an opposite median side region of the first hook (12) , a base portion (24a) of the inner hook (24) being spaced from a confronting base portion (12a) of the first hook (12) , the inner hook (24) and the second hook (13) presenting free end edges (24b, 13b) radially spaced from each other.

2. The arrangement, as set forth in claim 1, characterized in that the inner hook (24) is externally seated, on one side, against an end side region of the first hook (12) and against the tubular body (10) , at the junction region of the latter with the first hook (12) .

3. Arrangement, as set forth in claim 1, characterized in that the free end edge (24b) of the inner hook (24) is radially spaced from the first and from the second hook (12, 13) .

4. The arrangement, as set forth in claim 1, characterized in that it further comprises a sealing material (30) pressed in the interior of the inner hook

(24) and of the second hook (13) and between the inner surface for the seating of the median hook (23) against the second hook (13) .

5. The arrangement, as set forth in claim 4, characterized in that the sealing material (30) is also pressed between at least part of the radial extension of the inner surface onto which the outer hook (22) is seated against the first hook (12) , from the junction region between the first and the second hooks (12, 13) .

6. The arrangement, as set forth in claim 1, characterized in that the first hook (12) , the outer hook (22) and the inner hook (24) are positioned, at least in part, on the same side of a plane (P) transversal to the longitudinal axis of the tubular body (10) , the second hook (13) and the median hook (23) being positioned, at least in part, on the other side of said plane (P) . 7. The arrangement, as set forth in claim 6, characterized in that the free end edges (13b, 24b) of the second hook (13) and of the inner hook (24) are disposed over said plane (P) .

8. The arrangement, as set forth in claim 1, characterized in that the end wall (20) of the tubular body (10) defines a bottom wall of the recipient.

9. The arrangement, as set forth in claim 1, characterized in that the end wall (20) of the tubular body (10) defines an annular upper wall of the recipient. 10. The arrangement, as set forth in claim 1, characterized in that the tubular body (10) and the end wall (20) are each formed in a metallic sheet, incorporating, in a single piece, the outer flange (11) and the closure flange (21) , respectively. 11. A double seaming process for recipients which comprise a tubular body (10) having an end edge (10a) to be double seamed to a peripheral edge (20a) of an end

wall (20) of the recipient, said process being characterized in that it comprises the steps of:

- forming an outer flange (11) in the end edge (10a) of the tubular body (10) ; - forming a closure flange (21) in the peripheral edge (20a) of the end wall (20) ;

- seating the end wall (20) onto the end edge (10a) of the tubular body (10) , so as to dispose the closure flange (21) over outer flange (11) ; - carrying out a first double seaming operation, bending the outer edge of the closure flange (21) in order to form an inner hook (24) carrying, in its interior, a respective portion of the sealing material (30) ; carrying out a second double seaming operation, progressively deforming the closure flange (21) and the outer flange (11) , so as to form: with the outer flange

(11) , rounded U-shaped first and second hooks (12, 13), which are turned to opposite axial directions; and, with the closure flange (21) , an outer hook (22) , a median hook (23) and the inner hook (24), which are all rounded U-shaped, the outer hook (22) and the median hook (23) having their inner surfaces seated onto the whole extension of the first (12) and of the second hook (13), respectively, said inner hook (24) being disposed in the interior of the first hook (12), so as to be externally seated, on one side, against at least one of the parts of tubular body (10) and side region of the first hook (12) and, on the other side, against an opposite median side region of the first hook (12), a base portion (24a) of the inner hook (24) being spaced from a confronting base portion (12a) of the first hook (12) , the inner hook (24) and the second hook (13) presenting free end edges (24b, 13b) radially spaced from each other.

12. The process, as set forth in claim 11, characterized in that the second double seaming operation is made in a way that the inner hook (24) remains seated, on one side, against an end side region of the first hook (12) and

against the tubular body (10) , at the junction region of the latter with the first hook (12) .

13. The process, as set forth in claim 11, characterized in that the second double seaming operation maintains the free end edge (24b) of the inner hook (24) radially spaced from the first and the second hooks (12, 13) .

14. The process, as set forth in claim 11, characterized in that the second double seaming operation is made so as to position the first hook (12) , the outer hook (22) and the inner hook (24) , at least partially on the same side of a plane (P) transversal to the longitudinal axis of the tubular body (10), and the second hook (13) and the median hook (23) at least partially on the other side of said plane. 15. The process, as set forth in claim 14, characterized in that the free end edges (13b, 24b) of the second hook (13) and the inner hook (24) are disposed over said plane

(P) •

16. The process, as set forth in claim 11, characterized in that it further comprises the step of applying and aggregating a sealing material (30) against a radial extension of the inner surface of the closure flange (21), from the outer edge thereof.

17. The process, as set forth in claim 16, characterized in that the sealing material (30) is pressed between at least part of the radial extension of the inner surface onto which the outer hook (22) is seated against the first hook (12) , from the junction region between the first and the second hooks (12, 13) .

Description:

DOUBLE SEAMING ARRANGEMENT AND DOUBLE SEAMING PROCESS FOR RECIPIENTS

Field of the Invention

The present invention refers to a double seaming arrangement to be applied to recipients generally formed in metallic sheet or in sheets of composite material and which comprise a tubular body, usually but not necessarily cylindrical, having at least one end edge in which is double seamed a peripheral edge of an end wall, .which can be defined by a totally closed bottom or upper wall, or by an annular upper wall, defining a seat for the seating of a lid. The invention further refers to a process for carrying out said double seam in a lower number of operations and leading to an arrangement which guarantees a high level of tightness, even upon deformation of the double seam by destructive impacts. Prior Art

There are well known from the prior art the double seams that are used to reliably and tightly attach the peripheral edge of one or both end walls to the respective end edges of a tubular body, generally obtained in metallic sheet.

Some of these double seams are known as triple seams, such as that illustrated in figure 1, and according to which the end edge 10a of the tubular body 10 incorporates an outer flange 11, which is bent to form rounded U-shaped first and second hooks 12, 13, which are turned to opposite axial directions. In these triple seams, the peripheral edge 20a of the end wall 20 incorporates a closure flange 21, which is bent to form an outer hook 22, a median hook 23 and an inner hook 24, which are all rounded U-shaped, with the inner hook 24 being disposed in the interior of the first hook 12 and turned to the same axial direction of the latter.

In this known prior art double seam described in patent EP 0 065 842 Bl, the double seaming is carried

out for deforming the outer flange 11 and the closure flange 21 through an operation which includes the radial compression of the interposed hooks, in order to make the inner surface of the outer hook 22 and of the median hook 23 and the outer surface of the inner hook 24 be seated, throughout the whole extension thereof, in the radial direction, against the outer surface of the first and the second hook 12, 13 and against the inner surface of the first hook 12. The free end edges 13b and 24b of the second hook 13 and of the inner hook 24, which are turned to opposite axial directions, are disposed on opposite sides of a plane P transversal to the longitudinal axis of the tubular body 10 and which intersects the second hook 13 and the inner hook 24 in two extensions radially spaced from each other, each extension being defined in a respective hook.

Between the first hook 12 and the inner hook 24 there is usually pressed a sealing material 30, generally made in rubber or resin and applied to the closure flange 21, in liquid or semi-liquid state, before the double seaming operation.

The known triple seam commented above allows obtaining a reliable hermetic incorporation of an end wall 20 to the tubular body 10 of the recipient, through only one double seaming operation.

However, although reliable and hermetic, this triple seam and also others of similar construction, such as that proposed in US patent 4,540,323, present the inconvenience of having the hooks of the outer flange

11 and of the closure flange 21 seated to each other throughout the whole extension thereof, which seat is obtained in a final step of radial compression of the hooks and which is required for obtaining the desired level of tightness.

The fact that the hooks are totally seated to each other causes the hooks to be deformed, in case of

accidental drops, compromising their final double seamed condition required to guarantee the tightness, since the double seaming region is the most likely to suffer displacements by impacts caused during operations of storage and transport of the recipients. This deficiency is particularly serious for recipients of dangerous products, in which is required the maintenance of the double seaming tightness in case of accidental drops, respecting the international rules on this issue. In these known triple seams, the deformation of the double seamed hooks, even being relatively small, tends to negatively affect the required degree of tightness, mainly for storage of certain products. Another drawback of these known triple seams is the need for radially greater outer and closure flanges for obtaining the overlapping, in the axial direction, of the free end edges 13b, 24b of the second hook 13 and the inner hook 24, as can be seen in figure 1 of the enclosed drawings.

As a result, these double seams consume an amount of metallic sheet that comprises the radial extensions of the outer flange and the closure flange, said radial extensions corresponding to the axial overlapping of the free end of said flanges in the interior of the double seaming.

Another inconvenient aspect of the known double seams is the fact that the sealing material, which is pressed in the inner region of the hooks, is led to expand through the mutual seating region between the first hook 12 and the inner hook 24, towards the exterior of the recipient, as illustrated in figure 1 of the enclosed drawings, tending to cover a relatively short sealing extension between the tubular body and the end wall.

Summary of the Invention

As a function of the inconveniences mentioned above

and related to the triple seams of the type considered herein, it is an object of the present invention to provide a double seaming arrangement for the end walls of recipients provided with a tubular body, which allows obtaining a reliable double seam, which is capable to deform to absorb impacts provoked by accidental shocks, maintaining the tightness of the recipient . It is a further object of the present invention to provide a double seaming arrangement, such as mentioned above, which uses less material for the formation of the different hooks.

It is one more object of the present invention to provide a double seaming arrangement, such as mentioned above, which further comprises a sealing material pressed in the interior of the second hook and of the inner hook and also between the second hook and the median hook, and expanding towards the seating region between the first hook and the outer hook, i.e., throughout a relatively long sealing extension.

It is also an object of the present invention to provide a process for carrying out the double seaming arrangement mentioned above. The two first objects mentioned above are attained by a double seaming arrangement to be applied to a recipient of the type considered herein, having the end edge of the tubular body incorporating an outer flange which is bent toward the tubular body, so as to form rounded U-shaped first and second hooks, which are turned to opposite axial directions, and also the peripheral edge of the end wall incorporating a closure flange which is bent so as to form an outer hook, a median hook and an inner hook, which are all rounded U-shaped. According to the invention, the outer hook and the median hook present their inner surface seated onto the whole extension of the first and of the second

hook, respectively, the inner hook being disposed in the interior of the first hook, so as to be externally- seated, on one side, against at least one of the parts of tubular body and side region of the first hook and, on the other side, against an opposite median side region of the first hook, a base portion of the inner hook being spaced from a confronting base portion of the first hook, the inner hook and the second hook presenting free end edges radially spaced from each other.

This construction allows the double seam to present inner hollow spaces and different sealing regions upon the mutual seating between the confronting hooks, permitting that, in case one or more hooks are deformed by shocks caused, for example, by accidental drops, the deformation be absorbed by the inner regions of the hooks, without the double seam losing its degree of tightness. Still according to the present invention, the double seam is made by only two operations in a double seaming equipment, said double seaming being carried out so that the first hook, the outer hook and the inner hook are positioned, at least in part, on the same side of a plane P transversal to the longitudinal axis of the tubular body, the second hook and the median hook positioned, at least in part, on the other side of said plane P. Preferably, these two hook assemblies are integrally positioned on opposite sides of said plane P and, still more preferably, the free end edges of the inner hook and of the second hook are positioned on said plane P. Brief Description of the Drawings

The invention will be described below, with reference to the enclosed drawings, given by way of example of an embodiment of the invention and in which:

Figure 1 represents a radial cross sectional view of the periphery of a recipient, illustrating the double

seam of an end wall in the tubular body of the recipient, said double seam being formed according to the prior art ;

Figure 2 represents a radial cross sectional view of the periphery of the tubular body of a recipient, with an end wall prepared to be double seamed to the tubular body, according to the present invention, said view also schematically illustrating the relative positioning of the double seaming tools; Figure 3 represents a view similar to that of figure

2, but illustrating the closure flange being bent in an initial phase of the double seaming operation; Figure 4 represents a view similar to that of figure

3, but illustrating the outer flange and the closure flange totally bent and defining the respective hooks of the double seam in the finished condition; and Figure 5 represents an enlarged detail of the part of figure 4 that defines the cross section of the double seaming arrangement in its finished condition. Description of the Invention

As already previously mentioned, the invention refers to the provision of double seaming operations for recipients of the type which comprises a tubular body 10, generally but not necessarily cylindrical, formed in metallic sheet or in other adequate simple or compound material, having an end edge 10a in which is double seamed a peripheral edge 20a of an end wall 20, which can be a closed wall, such as a bottom wall of the recipient, or an annular upper wall, defining a seat for seating and retaining a lid which is not illustrated, since this construction is well known from the prior art .

According to the present invention, the tubular body 10 is submitted to an initial operation of deformation, by well known prior art proceedings and means, in order to form, in a single piece with its end edge 10a, an end flange 11 with a radial extension

predetermined as a function of the double seam to be formed.

As illustrated in figure 2 of the enclosed drawings, the end wall 20, generally formed in metallic sheet, is conformed to present an outwardly bent closure flange 21 presenting a radial extension, previously defined as a function of the double seam to be formed and which is invariably greater than the radial extension of the outer flange 11 of the tubular body 10. The thus previously conformed end wall 20 is seated on the end edge 10a of the tubular body 10, so as place the closure flange 21 over the outer flange 11. Over the surface of the closure flange 21 facing the outer flange 11 is applied, by well known prior art proceedings, a layer of a sealing material 30, usually made of adequate rubber or resin and which is applied in a liquid or semi-liquid condition. The assembly formed by the tubular body 10 and the end wall 20 is then positioned in a double seaming equipment, not illustrated and represented only by the tools Fl and Rl, and the first double seaming operation is allowed to start, by radially displacing the double seaming tool Rl, generally in the form of a double seaming roller, so that the outer edge of the closure flange 21 is progressively bent to form an inner hook 24, carrying, in its interior, a respective portion of the sealing material 30, as illustrated in figure 3. After finishing the first double seaming operation, the double seaming tool Rl is substituted by a second deformation tool R2 , as illustrated in figure 4, which is also progressively displaced in the inward radial direction, in order to progressively deform the closure flange 21 and the outer flange 11, so as to form, with the outer flange 11, rounded U-shaped first and second hooks 12, 13, which are turned to opposite axial directions and, with the closure flange 21, an

outer hook 22, a median hook 23 and said inner hook 24, which are all rounded U-shaped. This particular embodiment of the present invention is illustrated in figures 4 and 5 and obtained as a function of the profile imparted to the second deformation tool R2 , usually also defined by one or more double seaming rollers, which are displaced around the end edge of the tubular body 10 in a constructive arrangement well known from the prior art . According to the present invention, the deformation of the outer flange 11 and of the closure flange 21, by the second deformation tool R2 , is made so that the outer hook 22 and the median hook 23 present their inner surface seated onto the whole extension of the first and of the second hook 12, 13, respectively, said inner hook 24 being disposed in the interior of the first hook 12, so as to remain externally seated, on one side, against at least one of the parts of tubular body 10 and side region of the first hook 12 and, on the other side, against an opposite median side region of the first hook 12.

As can be seen in figures 4 and 5, the double seaming arrangement of the invention is formed in order that the base portion 24a of the inner hook 24 remains spaced from a confronting base portion 12a of the first hook 12, the inner hook 24 and the second hook 13 remaining with their free end edges 24b, 13b radially spaced from each other. The construction defined above allows a hollow space region to be created between the base portion 24a of the inner hook 24 and the confronting base portion 12a of the first hook 12, which region allows deformations of the double seam when submitted to impacts, absorbing the shock energy in order to maintain the tightness of the double seam, even with this deformation that uses the hollow spaces for accommodating the deformed elements .

Within the constructive solution mentioned above, it should be further noted that the second double seaming operation is made so that the inner hook 24 remains seated, on one side, against an end side region of the first hook 12 and against the tubular body 10, at the junction region of the latter with the first hook 12. It should be understood herein that this is the preferred embodiment of the invention, as the inner hook 24 can be conformed to remain seated only against an end side region of the first hook 12 or only against the tubular body 10 in a region of said parts next to that junction region with the other part. Preferably, the second double seaming operation is also designed to maintain the free end edge 24b of the inner hook 24 radially spaced from the first and from the second hook 12, 13. Considering the radial spacing between the free end edges 24b, 13b of the inner hook 24 and of the second hook 13 and also the spacing of the free end edge 24b of the inner hook 24 in relation to the second hook 13, there is provided, in the interior of the double seaming, an effective hollow space additional to that previously commented, and defined between the first hook 12 and the inner hook 24, in order to allow more intense deformations of said hooks when they are submitted to an impact caused, for example, by accidental drop, without such deformations jeopardizing the mutual seating regions of the first and of the second hook 12, 13 against, respectively, the outer hook 22 and the median hook 23, in the interior of which seating regions being pressed a respective portion of the sealing material 30, which is pressed in the interior of the inner hook 24 and second hook 13. It should be noted herein that the sealing material 30, by expanding from the center of the central region of the double seam to the mutual seating region between the second hook 13 and the median hook 23, tends to expand towards the inner hook

22 and the first hook 12, extending along a sealing region facing the interior of the recipient and which is longer than that defined between the inner hook 24 and the first hook 12 and which extends towards the exterior of the recipient .

Further according to the preferred embodiment illustrated in figures 4 and 5, the second double seaming operation is carried out so as to position the first hook 12, the outer hook 22 and the inner hook 24, at least partially on the same side of a plane P, which is transversal to the longitudinal axis of the tubular body 10, and the second hook 13 and the median hook 23, at least partially of the other side of said plane P. However, in the illustrated embodiment, the free end edges 13b, 24b of the second hook 13 and of the inner hook 24 are disposed over said plane P, making the first hook 12, the outer hook 22 and the inner hook 24 be totally positioned on one side of the plane P, while the second hook 13 and the median hook 23 are integrally positioned on the opposite side of said plane P. i

The double seaming arrangement proposed by the present invention permits eliminating the usual overlapping, in the axial direction, between the end regions of the outer flange 11 and the closure flange 21, in the interior of the double seam. In the illustrated constructive example, the free end edges 24b, 13b of the inner hook 24 and of the second hook 13, respectively, are situated in the same plane P transversal to the longitudinal axis of the tubular body 10, eliminating any axial overlapping between said edges. Furthermore, it should be understood that said free end edges can also be spaced in relation to said plane P, reducing even more the quantity material necessary for constitution of the outer flange 11 and of the closure flange 21 to form a reliable and tight double seam and which can resist accidental impacts,

without losing its degree of tightness, as required for storing dangerous products .

While only one preferred way of carrying out the invention has been illustrated herein, it should be understood that changes in the form and arrangements could be made, without departing from the inventive concept defined in the claims accompanying the present specification.