Title of Invention	"DEVICE FOR SEALED COUPLING OF TWO SMOOTH TUBES"
Abstract	The device comprises a sleeve (10) suitable for being disposed around the facing ends of the two tubes and provided with means for decreasing its diameter under the action of tightening means (22, 24). The device further comprises a sealing ring (12) disposed inside the sleeve (10) for the purpose of surrounding the ends of the tubes. Said ring is constituted by a strip looped back on itself and having its ends suitable for coming into engagement contact during the tightening. At least one of the male and female shaped portions of a male/female set has contact edges formed on the contact tabs (32A, 32B), said tabs being suitable for deflecting in the direction facilitating penetration of the male shaped portion into the female shaped portion while the male shaped portion (28) is engaging into the female shaped portion (30) under the effect of the tightening.

Title of Invention

"DEVICE FOR SEALED COUPLING OF TWO SMOOTH TUBES"

Abstract

The device comprises a sleeve (10) suitable for being disposed around the facing ends of the two tubes and provided with means for decreasing its diameter under the action of tightening means (22, 24). The device further comprises a sealing ring (12) disposed inside the sleeve (10) for the purpose of surrounding the ends of the tubes. Said ring is constituted by a strip looped back on itself and having its ends suitable for coming into engagement contact during the tightening. At least one of the male and female shaped portions of a male/female set has contact edges formed on the contact tabs (32A, 32B), said tabs being suitable for deflecting in the direction facilitating penetration of the male shaped portion into the female shaped portion while the male shaped portion (28) is engaging into the female shaped portion (30) under the effect of the tightening.

Full Text	A DEVICE FOR COUPLING TOGETHER TWO SMOOTH TUBES IN LEAKTIGHT MANNER The present invention relates to a device for coupling together in leaktight manner two smooth tubes disposed end-to-end and having substantially the same diameter, the device comprising a sleeve suitable for being disposed around the facing ends of the two tubes, said sleeve being provided with means for enabling its diameter to be decreased under the action of tightening means, the device further comprising a sealing ring suitable for being disposed inside the sleeve for the purpose of surrounding the facing ends of the two tubes, said ring being constituted by a strip looped back on itself and having two ends suitable for coming into engagement contact, via at least one male/female set comprising a male shaped portion suitable for being engaged in a female shaped portion when, with the ring being situated inside the sleeve, said sleeve is tightened around the facing ends of the tubes. A device of that type is known, e.g. from the Applicant's Patent Document EP 1 181 477. On tightening that device, as disposed around the tubes to be coupled together, the male shaped portion penetrates gradually into the female shaped portion so that the engagement contact that serves to procure the leaktightness is established. In EP 1 181 477, the male shaped portion is formed by a tongue that penetrates into a notch forming the female shaped portion. In view of the respective widths of the male and female shaped portions, the engagement contact is established even though the free end of the tongue remains some distance from the end wall of the notch. During tightening, the tongue continues to penetrate into the notch, thereby causing the male and female shaped portions to be deformed. That deformation itself generates opposing forces that tend to oppose penetration of the tongue into the notch. Thus, during tightening, the leaktightness is guaranteed very well, but there exists a risk that the above-mentioned opposing forces might cause unacceptable deformations, e.g. bending of the ring in certain regions thereof. An object of the present invention is to improve that state of the art further by proposing a device that is substantially free of the above-mentioned drawbacks. This object is achieved by the fact that at least one of the male and female shaped portions of a male/female set has contact edges formed on contact tabs, said tabs being suitable for deflecting in the direction facilitating penetration of the male shaped portion into the female shaped portion while the male shaped portion is engaging into the female shaped portion under the effect of the tightening. Thus, in accordance with the invention, the engagement contact that procures the leaktightness is established on the contact edges of the contact tabs. Since said contact tabs are suitable for deflecting, the above-mentioned opposing forces are reduced and it is guaranteed that the deformation caused by the male shaped portion penetrating into the female shaped portion preferentially affects predetermined zones of the sealing ring, namely the contact tabs. Advantageously, deflection setbacks are provided on those sides of the contact tabs that are opposite from the contact edges. Said deflection setbacks form spaces into which the tabs move as they are deflecting under the effect of the male shaped portion penetrating into the female shaped portion. Advantageously, the contact tabs are connected to the end of the strip that carries them via nicked base portions. Said nicked base portions locally reduce the resistance to bending of the contact tabs and thus impart respective preferential deflecting directions to them. In an advantageous embodiment, the male shaped portion of the male/female set comprises a tongue while the female shaped portion of said set comprises a notch defined between two contact tabs, so that said tongue can penetrate into said notch, and at least one of the transverse dimensions constituted by the width of the tongue and by the width of the notch decreases going in the direction in which the tongue penetrates into the notch. Advantageously, the female shaped portion of the male/female set comprises a notch while the male shaped portion of said set comprises two side contact tabs suitable for penetrating into said notch, and at least one of the transverse dimensions constituted by the width of the notch and by the gap between the contact edges of the contact tabs decreases going in the direction in which said tabs penetrate into said notch. The invention can be better understood and its advantages appear more clearly on reading the following detailed description of an embodiment given by way of non-limiting example. The description refers to the accompanying drawings, in which: • Figure 1 is a perspective view of a device of the invention; • Figure 2 is a view of the device seen from above; • Figure 3 is a view from above of the sealing ring of the device, seen looking along arrow III of Figure 1; • Figure 4 is a view of the same ring, seen looking along arrow IV of Figure 3; • Figure 5 is a view analogous to the Figure 3 view, for a variant embodiment of the ring; • Figure 6 shows male and female shaped portions of a variant of a ring; and Figure 7 shows male and female shaped portions in another variant. The device of Figure 1 includes a sleeve 10 inside which a sealing ring 12 is disposed. This device serves for coupling together in leaktight manner two smooth tubes that are disposed end-to-end and that have substantially the same diameter, it being necessary to engage the two facing ends of the tubes into the ring 12 until they come into abutment with abutment projections 13 and on either side thereof. For reasons of convenience, the two tubes are not shown in Figure 1, but reference can be made to EP 1 181 477 for assembly details. The sleeve 10 can be analogous to the sleeve disclosed in EP 1 181 477. It has a belt portion 10A and tightening means, disposed at its two facing ends, between which tightening means a slot 11 is defined that is longitudinal, i.e. parallel to the axis of the sleeve. During tightening, the width of said slot is decreased, thereby reducing the diameter of the belt portion 10A correspondingly. However, in the advantageous embodiment shown in Figures 1 and 2, the sleeve is different from the sleeve of EP 1 181 477. For the purpose of tightening it, it has at least one pair of projecting lugs between which the above-mentioned slot 11 is defined. In this example, it has two pairs of projecting lugs, 14A & 14B and 16A & 16B. The lugs in each pair are disposed facing each other. Each lug has a connection portion 17 via which it is connected to the belt portion 10A, and a tightening wall 18 with which the tightening means come into engagement. Said tightening wall 18 is folded back towards the belt portion from the connection portion 17. A space is formed between the connection portion and the tightening wall. The connection portion is curved, its concave side facing the tightening wall. At its base, the connection portion has at least one protuberance 17A in which its curvature is locally increased. As can be seen more clearly in Figure 2, each lug has two protuberances 17A of this type, at respective ones of its two opposite axial ends. Reinforcement means equip the lugs for the purpose of opposing deformation (flattening) thereof under the action of the tightening means. In the example shown, for each lug, said reinforcement means comprise a reinforcement insert 20 that is disposed in the space formed between the connection portion 17 and the tightening wall 18. Said tightening insert is in the shape of a trough whose web is disposed against the connection portion, while its free ends co-operate with the tightening wall. For each pair of lugs, the tightening means comprise a bolt 22, whose shank 22A is engaged through facing holes in the two lugs of the pair in question, so as to pass through said lugs, and whose head 22B rests against the tightening wall of one of the lugs, and a nut 24, disposed against the tightening wall of the other lug, for the purpose of co-operating by screw engagement on the shank of the bolt. In this example, two identical tightening systems are provided, each of which comprises a pair of lugs, a bolt and a nut. For the purpose of decoupling the tightening forces, a transverse slot 26 shown in Figure 2 is provided between said two systems in the belt portion of the sleeve. The inserts 20 disposed in the lugs 14B and 16B have holes provided through their webs so as to enable the shanks of the bolts to pass through them. Naturally, the above-described particular shape of the sleeve and the tightening means can be replaced by any other means of known type. In particular, the sleeve can be of the type described in Patent Application EP 1 181 477, or else it can be a sleeve of the above-mentioned type, but provided with a single pair of lugs and with a single nut-and-bolt assembly. Similarly, the above-mentioned reinforcement means can be replaced with other reinforcement means having an equivalent effect, e.g. by an appropriate fold-back formed from the tightening wall 18 of a lug. A description follows of the shape of the sealing ring of the present invention. This ring is constituted by a strip that is looped back on itself and whose two ends are shaped such that they are suitable for coming into mutual engagement contact. Thus, in Figures 1 and 3, a first end of the ring is provided with a male shaped portion formed by a tongue 28, while the second end is provided with a female shaped portion comprising a notch 30 into which the tongue 28 penetrates in order to establish the engagement contact necessary for procuring the leaktightness. More precisely, in the example of Figures 1 and 3, the notch 30 of the female shaped portion is defined between two contact tabs 32A and 32B that are suitable for deflecting in the direction facilitating penetration of the male shaped portion into the female shaped portion, during the tightening of the collar that causes such penetration. More precisely, the contact engagement is established between two "inside" side edges 30A and 30B of the contact tabs 32A and 32B and two "outside" side edges 28A and 28B of the tongue 28. Figure 3 shows that the width 128 of the tongue, as measured parallel to the axis A of the sealing ring and of the sleeve, and the width 130 of the notch 30, as measured in the same way, decrease going in the direction S in which the tongue penetrates into the notch. Thus, as in EP 1 181 477, the contact edges of the male and female shaped portions can come into engagement before the collar is tightened, while the ring is in the situation shown in Figure 3. During tightening, the tongue 28 is constrained to advance further into the notch 30, thereby establishing contact between the contact edges over contact lengths that are sufficient for guaranteeing good leaktightness. While the tongue is advancing further into the notch in this way, deformation is generated. In accordance with the invention, said deformation results in the tabs 32A and 32B deflecting in the direction facilitating penetration of the tongue into the notch, i.e. in the direction increasing the width of the notch as indicated by the arrows P. Figure 3 shows that deflection setbacks 34A and 34B are provided on those sides of the contact tabs 32A and 32B that are opposite from the contact edges 30A and 30B. The above-mentioned deflecting thus takes place in said setbacks. Apart from the setbacks and the notch 30, the free end 12A of that end of the ring 12 at which the notch 30 is formed is situated on the same line 1, parallel to the axis A about which the strip 12 is looped. Similarly, apart from the tongue 28, the free edge 12B of that end of the ring at which said tongue is formed is also situated on the same line I1, parallel to the axis A. In order to facilitate procuring leaktightness, provision is made for the lines 1 and 1' to be as close as possible together when the device is clamped onto two coupled-together smooth tubes. Mention is made above of the presence of the projections 13 projecting from the inside periphery of the ring 12 for the purpose of forming wedging surfaces for the free ends of the coupled-together tubes. As can be seen in Figure 4, said ring is further provided with projections 15 that project from its outside periphery. These projections are disposed in indentations 9 in the belt portion 10A of the sleeve 10, so as to wedge the ring 12 angularly relative to the sleeve. It is important for the male and female shaped portions that establish the leaktight contact to be close to the tightening means, while also being situated under a continuous portion of the belt portion 10. If the space between the two facing ends of the ring 12 were to find itself at the intersection with above-mentioned slot 11 or with above-mentioned slot 26, the leaktightness would be lost. Furthermore, it is desirable for the male and female shaped portions to be close to the tightening means so as to be affected directly by the tightening in a manner such as to facilitate penetration of the tongue into the notch. As can also be seen in Figure 3, the contact tabs are connected to the end of the strip that carries them via nicked base portions. More precisely, the deflection setbacks 34A and 34B that are provided on the sides of the contact tabs that are opposite from the notch 30 have slanting nicks 36A and 36B situated in the vicinities of the respective tabs 32A and 32B. Said nicks are disposed in the regions of the end-walls of the setbacks that are adjacent to the tabs 32A and 32B and they are angularly positioned in a manner such as to converge going in the direction S in which the tongue penetrates into the notch 30. Thus, the tabs deflecting as indicated by the arrows P in Figure 3 is facilitated. In the example shown in Figures 1 and 3, the ring 12 has a single male/female set comprising the above-mentioned tongue 28 and the above-mentioned notch 30. In Figure 5, it can be seen that, in a variant, a plurality of adjacent sets can be provided at the ends of the ring 112. Three analogous male/female sets can be seen, comprising, respectively, a tongue 128A and a notch 130A, a tongue 128B and a notch 13OB, and a tongue 128C and a notch 13OC. Each of these sets is analogous to the set that is described above with reference to Figure 3, and thus includes two contact tabs, e.g. 132A and 132B, two deflection setbacks, e.g. 134A and 134B, disposed on those sides of the tabs that are opposite from the notch, and two nicks 136A and 136B analogous to the above-described nicks 36A and 36B. The free edge 112A of the ring 112 that is equipped with the female shaped portions is situated on a line 1 parallel to the axis about which the sleeve is looped back on itself, i.e. the free ends of the tabs are situated on said line, as are the free ends of all of the portions formed between the notches and the deflection setbacks. Intermediate tabs 113, locally bringing the free end 112A onto the line 1 are provided between the deflection setbacks of two adjacent sets. Similarly, the free edge 112B of the ring on which the tongues 128A, 128B, and 128C are situated is situated on a line 1' parallel to the same axis, relative to which only the tongues project. Naturally, although the example of Figure 5 shows three male/female sets, a different number of sets could be provided. However, it is advantageous, in order to balance the forces exerted on the ring during tightening, for said ring to be symmetrical about its midplane PS perpendicular to its loop axis A. Thus, in Figure 2, the tongue 28 and the notch 30 are centered relative to such a plane PS and the central male/female set 128B/130B of Figure 5 is also centered on such a plane PS. In Figure 5, it should be noted that, between two adjacent tongues, e.g. 128A and 128B, a notch 127 is provided into which two contact tabs penetrate, e.g. tabs 132A and 133B belonging to the two adjacent male/female sets. Precisely, with reference to Figure 6, it can be understood that, in a variant of the invention, it is possible to choose to make provision for the female shaped portion to comprise a notch 230 and for the male shaped portion to comprise two side contact tabs, respectively 232A and 232B, suitable for penetrating into said notch. In which case, the contact engagement is established between the "outside" contact edges 23OA and 230B of the tabs 232A and 232B and "inside" contact edges 228A and 228B of the notch 230. In which case, the male shaped portion of the male/female set in question thus includes the two above-mentioned tabs 232A and 232B. Figure 6 shows that the width 1230 of the notch, as measured parallel to the axis of a bearing A of the ring, and the gap 1230 between the contact edges 230A and 230B decrease going in the direction S in which the tabs penetrate into the notch. The male shaped portion in Figure 6 further comprises a central tab 231 which is disposed between the contact tabs 232A and 232B while being spaced apart therefrom by deflection setbacks, respectively 234A and 234B. It is possible to omit the central tab 231A and merely to make provision such that, on deflecting, the tabs 232A and 232A deflect into the space formed between them. However, as explained above, it is advantageous for the free edges of the two ends of the ring to come as close together as possible, so that it is desirable, by means of the tab 231, to bring the free end of the male shaped portion locally to the level of the free ends of the tabs 232A and 232B. In Figure 6, the deflection setbacks are provided with slanting nicks, respectively 236A and 236B which are situated in the vicinities of the contact tabs 232A and 232B. Said nicks converge going in the direction in which the male shaped portion penetrates into the female shaped portion, for facilitating deflection of the tabs as indicated by the arrows P', in the above-mentioned deflection setbacks. The variant of Figure 7 uses contact tabs both for its male shaped portion and for its female shaped portion. In this variant, the male shaped portion is identical to the male shaped portion of Figure 6 and its various component elements are designated by the same references as in that figure. The female shaped portion is identical to the female shaped portion of Figure 3, and its various consecutive elements are identified by the same references as in that Figure. Thus, when the male shaped portion penetrates further into the female shaped portion, the tabs 232A and 232B of the male shaped portion tend to deflect into the setbacks 234A and 234B formed between them, on either side of the central tab 231, while the tabs 32A and 32b that define the notch 30 of the female shaped portion between them tend to deflect into the deflection setbacks 34A and 34B provided on either side of said tabs. The slanting nicks 36A, 36B, 236A and 236B facilitate this deflection. CLAIMS 1. A device for coupling together in leaktight manner two smooth tubes disposed end-to-end and having substantially the same diameter, the device comprising a sleeve (10) suitable for being disposed around the facing ends of the two tubes, said sleeve being provided with means (11) for enabling its diameter to be decreased under the action of tightening means (22, 24), the device further comprising a sealing ring (12, 112) suitable for being disposed inside the sleeve (10) for the purpose of surrounding the facing ends of the two tubes, said ring being constituted by a strip looped back on itself and having two ends (12A, 12B; 112A, 112B) suitable for coming into engagement contact, via at least one male/female set comprising a male shaped portion (28; 128A, 128B, 128C; 232A, 232B) suitable for being engaged in a female shaped portion (30; 130A, 130B, 130C; 230) when, with the ring being situated inside the sleeve (10), said sleeve is tightened around the facing ends of the tubes; said device being characterized in that at least one of the male and female shaped portions of a male/female set has contact edges (30A, 30B; 230A, 230B) formed on contact tabs (32A, 32B; 132A, 132B; 232A, 232B), said tabs being suitable for deflecting in the direction facilitating penetration of the male shaped portion into the female shaped portion while the male shaped portion is engaging into the female shaped portion under the effect of the tightening. 2. A device according to claim 1, characterized in that deflection setbacks (34A, 34B; 134A, 134B) are provided on those sides of the contact tabs (32A, 32B; 132A, 132B) that are opposite from the contact edges (30A, 3OB) . 3. A device according to claim 1 or claim 2, characterized in that the contact tabs (32A, 32B; 132A, 132B) are connected to the end of the strip that carries them via nicked base portions (36A, 36B; 136A, 136B). 4. A device according to any one of claims 1 to 3, characterized in that the male shaped portion of the male/female set comprises a tongue (28; 128A) while the female shaped portion of said set comprises a notch (30; 130A) defined between two contact tabs (32A, 32B; 132A, 132B), so that said tongue can penetrate into said notch, and in that at least one of the transverse dimensions constituted by the width (128) of the tongue and by the width (130) of the notch decreases going in the direction in which the tongue penetrates into the notch. 5. A device according to claim 4, characterized in that deflection setbacks (34A, 34B; 134A, 134B) are provided on the sides of the contact tabs (32A, 32B; 132A, 132B) that are opposite from the notch (30; 130A). 6. A device according to claim 5, characterized in that the deflection setbacks (34A, 34B; 134A, 134B) are provided with slanting nicks (36A, 36B; 136A, 136B) situated in the vicinity of the contact tabs (32A, 32B; 132A, 132B). 7. A device according to any one of claims 1 to 6, characterized in that the female shaped portion of the male/female set comprises a notch (230; 30) while the male portion of said set comprises two side contact tabs (232A, 232B) suitable for penetrating into said notch (230; 30), and in that at least one of the transverse dimensions constituted by the width (1230) of the notch and by the gap (e230) between the contact edges (230A; 23OB) of the contact tabs decreases going in the direction in which said tabs penetrate into said notch. 8. A device according to claim 7, characterized in that said male shaped portion further comprises at least one central tab (231) disposed between the contact tabs (232A, 232B) while being spaced apart therefrom by deflection setbacks (234A, 234B). 9. A device according to claim 7, characterized in that the deflection setbacks (234A, 234B) are provided with slanting nicks (236A, 236B) situated in the vicinities of the contact tabs (232A, 232B).

Full Text

A DEVICE FOR COUPLING TOGETHER TWO SMOOTH TUBES IN LEAKTIGHT MANNER
The present invention relates to a device for coupling together in leaktight manner two smooth tubes disposed end-to-end and having substantially the same diameter, the device comprising a sleeve suitable for being disposed around the facing ends of the two tubes, said sleeve being provided with means for enabling its diameter to be decreased under the action of tightening means, the device further comprising a sealing ring suitable for being disposed inside the sleeve for the purpose of surrounding the facing ends of the two tubes, said ring being constituted by a strip looped back on itself and having two ends suitable for coming into engagement contact, via at least one male/female set comprising a male shaped portion suitable for being engaged in a female shaped portion when, with the ring being situated inside the sleeve, said sleeve is tightened around the facing ends of the tubes.
A device of that type is known, e.g. from the Applicant's Patent Document EP 1 181 477. On tightening that device, as disposed around the tubes to be coupled together, the male shaped portion penetrates gradually into the female shaped portion so that the engagement contact that serves to procure the leaktightness is established.
In EP 1 181 477, the male shaped portion is formed by a tongue that penetrates into a notch forming the female shaped portion. In view of the respective widths of the male and female shaped portions, the engagement contact is established even though the free end of the tongue remains some distance from the end wall of the notch. During tightening, the tongue continues to penetrate into the notch, thereby causing the male and female shaped portions to be deformed. That deformation itself generates opposing forces that tend to oppose penetration of the tongue into the notch.

Thus, during tightening, the leaktightness is guaranteed very well, but there exists a risk that the above-mentioned opposing forces might cause unacceptable deformations, e.g. bending of the ring in certain regions thereof.
An object of the present invention is to improve that state of the art further by proposing a device that is substantially free of the above-mentioned drawbacks.
This object is achieved by the fact that at least one of the male and female shaped portions of a male/female set has contact edges formed on contact tabs, said tabs being suitable for deflecting in the direction facilitating penetration of the male shaped portion into the female shaped portion while the male shaped portion is engaging into the female shaped portion under the effect of the tightening.
Thus, in accordance with the invention, the engagement contact that procures the leaktightness is established on the contact edges of the contact tabs. Since said contact tabs are suitable for deflecting, the above-mentioned opposing forces are reduced and it is guaranteed that the deformation caused by the male shaped portion penetrating into the female shaped portion preferentially affects predetermined zones of the sealing ring, namely the contact tabs.
Advantageously, deflection setbacks are provided on those sides of the contact tabs that are opposite from the contact edges.
Said deflection setbacks form spaces into which the tabs move as they are deflecting under the effect of the male shaped portion penetrating into the female shaped portion.
Advantageously, the contact tabs are connected to the end of the strip that carries them via nicked base portions.

Said nicked base portions locally reduce the resistance to bending of the contact tabs and thus impart respective preferential deflecting directions to them.
In an advantageous embodiment, the male shaped portion of the male/female set comprises a tongue while the female shaped portion of said set comprises a notch defined between two contact tabs, so that said tongue can penetrate into said notch, and at least one of the transverse dimensions constituted by the width of the tongue and by the width of the notch decreases going in the direction in which the tongue penetrates into the notch.
Advantageously, the female shaped portion of the male/female set comprises a notch while the male shaped portion of said set comprises two side contact tabs suitable for penetrating into said notch, and at least one of the transverse dimensions constituted by the width of the notch and by the gap between the contact edges of the contact tabs decreases going in the direction in which said tabs penetrate into said notch.
The invention can be better understood and its advantages appear more clearly on reading the following detailed description of an embodiment given by way of non-limiting example. The description refers to the accompanying drawings, in which:
• Figure 1 is a perspective view of a device of the
invention;
• Figure 2 is a view of the device seen from above;
• Figure 3 is a view from above of the sealing ring
of the device, seen looking along arrow III of Figure 1;
• Figure 4 is a view of the same ring, seen looking
along arrow IV of Figure 3;
• Figure 5 is a view analogous to the Figure 3 view,
for a variant embodiment of the ring;
• Figure 6 shows male and female shaped portions of
a variant of a ring; and

Figure 7 shows male and female shaped portions in another variant.
The device of Figure 1 includes a sleeve 10 inside which a sealing ring 12 is disposed. This device serves for coupling together in leaktight manner two smooth tubes that are disposed end-to-end and that have substantially the same diameter, it being necessary to engage the two facing ends of the tubes into the ring 12 until they come into abutment with abutment projections 13 and on either side thereof. For reasons of convenience, the two tubes are not shown in Figure 1, but reference can be made to EP 1 181 477 for assembly details.
The sleeve 10 can be analogous to the sleeve disclosed in EP 1 181 477. It has a belt portion 10A and tightening means, disposed at its two facing ends, between which tightening means a slot 11 is defined that is longitudinal, i.e. parallel to the axis of the sleeve. During tightening, the width of said slot is decreased, thereby reducing the diameter of the belt portion 10A correspondingly.
However, in the advantageous embodiment shown in Figures 1 and 2, the sleeve is different from the sleeve of EP 1 181 477. For the purpose of tightening it, it has at least one pair of projecting lugs between which the above-mentioned slot 11 is defined. In this example, it has two pairs of projecting lugs, 14A & 14B and 16A & 16B. The lugs in each pair are disposed facing each other. Each lug has a connection portion 17 via which it is connected to the belt portion 10A, and a tightening wall 18 with which the tightening means come into engagement. Said tightening wall 18 is folded back towards the belt portion from the connection portion 17. A space is formed between the connection portion and the tightening wall. The connection portion is curved, its concave side facing the tightening wall. At its base, the connection portion has at least one protuberance 17A

in which its curvature is locally increased. As can be seen more clearly in Figure 2, each lug has two protuberances 17A of this type, at respective ones of its two opposite axial ends.
Reinforcement means equip the lugs for the purpose of opposing deformation (flattening) thereof under the action of the tightening means. In the example shown, for each lug, said reinforcement means comprise a reinforcement insert 20 that is disposed in the space formed between the connection portion 17 and the tightening wall 18. Said tightening insert is in the shape of a trough whose web is disposed against the connection portion, while its free ends co-operate with the tightening wall.
For each pair of lugs, the tightening means comprise a bolt 22, whose shank 22A is engaged through facing holes in the two lugs of the pair in question, so as to pass through said lugs, and whose head 22B rests against the tightening wall of one of the lugs, and a nut 24, disposed against the tightening wall of the other lug, for the purpose of co-operating by screw engagement on the shank of the bolt. In this example, two identical tightening systems are provided, each of which comprises a pair of lugs, a bolt and a nut. For the purpose of decoupling the tightening forces, a transverse slot 26 shown in Figure 2 is provided between said two systems in the belt portion of the sleeve. The inserts 20 disposed in the lugs 14B and 16B have holes provided through their webs so as to enable the shanks of the bolts to pass through them.
Naturally, the above-described particular shape of the sleeve and the tightening means can be replaced by any other means of known type. In particular, the sleeve can be of the type described in Patent Application EP 1 181 477, or else it can be a sleeve of the above-mentioned type, but provided with a single pair of lugs and with a single nut-and-bolt assembly. Similarly, the

above-mentioned reinforcement means can be replaced with other reinforcement means having an equivalent effect, e.g. by an appropriate fold-back formed from the tightening wall 18 of a lug.
A description follows of the shape of the sealing ring of the present invention. This ring is constituted by a strip that is looped back on itself and whose two ends are shaped such that they are suitable for coming into mutual engagement contact. Thus, in
Figures 1 and 3, a first end of the ring is provided with a male shaped portion formed by a tongue 28, while the second end is provided with a female shaped portion comprising a notch 30 into which the tongue 28 penetrates in order to establish the engagement contact necessary for procuring the leaktightness.
More precisely, in the example of Figures 1 and 3, the notch 30 of the female shaped portion is defined between two contact tabs 32A and 32B that are suitable for deflecting in the direction facilitating penetration of the male shaped portion into the female shaped portion, during the tightening of the collar that causes such penetration. More precisely, the contact engagement is established between two "inside" side edges 30A and 30B of the contact tabs 32A and 32B and two "outside" side edges 28A and 28B of the tongue 28. Figure 3 shows that the width 128 of the tongue, as measured parallel to the axis A of the sealing ring and of the sleeve, and the width 130 of the notch 30, as measured in the same way, decrease going in the direction S in which the tongue penetrates into the notch.
Thus, as in EP 1 181 477, the contact edges of the male and female shaped portions can come into engagement before the collar is tightened, while the ring is in the situation shown in Figure 3. During tightening, the tongue 28 is constrained to advance further into the notch 30, thereby establishing contact between the contact edges over contact lengths that are sufficient

for guaranteeing good leaktightness. While the tongue is advancing further into the notch in this way, deformation is generated. In accordance with the invention, said deformation results in the tabs 32A and 32B deflecting in the direction facilitating penetration of the tongue into the notch, i.e. in the direction increasing the width of the notch as indicated by the arrows P.
Figure 3 shows that deflection setbacks 34A and 34B are provided on those sides of the contact tabs 32A and 32B that are opposite from the contact edges 30A and 30B. The above-mentioned deflecting thus takes place in said setbacks.
Apart from the setbacks and the notch 30, the free end 12A of that end of the ring 12 at which the notch 30 is formed is situated on the same line 1, parallel to the axis A about which the strip 12 is looped. Similarly, apart from the tongue 28, the free edge 12B of that end of the ring at which said tongue is formed is also situated on the same line I1, parallel to the axis A. In order to facilitate procuring leaktightness, provision is made for the lines 1 and 1' to be as close as possible together when the device is clamped onto two coupled-together smooth tubes.
Mention is made above of the presence of the projections 13 projecting from the inside periphery of the ring 12 for the purpose of forming wedging surfaces for the free ends of the coupled-together tubes. As can be seen in Figure 4, said ring is further provided with projections 15 that project from its outside periphery. These projections are disposed in indentations 9 in the belt portion 10A of the sleeve 10, so as to wedge the ring 12 angularly relative to the sleeve. It is important for the male and female shaped portions that establish the leaktight contact to be close to the tightening means, while also being situated under a continuous portion of the belt portion 10. If the space between the two facing ends of the ring 12 were to find

itself at the intersection with above-mentioned slot 11 or with above-mentioned slot 26, the leaktightness would be lost. Furthermore, it is desirable for the male and female shaped portions to be close to the tightening means so as to be affected directly by the tightening in a manner such as to facilitate penetration of the tongue into the notch.
As can also be seen in Figure 3, the contact tabs are connected to the end of the strip that carries them via nicked base portions. More precisely, the deflection setbacks 34A and 34B that are provided on the sides of the contact tabs that are opposite from the notch 30 have slanting nicks 36A and 36B situated in the vicinities of the respective tabs 32A and 32B. Said nicks are disposed in the regions of the end-walls of the setbacks that are adjacent to the tabs 32A and 32B and they are angularly positioned in a manner such as to converge going in the direction S in which the tongue penetrates into the notch 30. Thus, the tabs deflecting as indicated by the arrows P in Figure 3 is facilitated.
In the example shown in Figures 1 and 3, the ring 12 has a single male/female set comprising the above-mentioned tongue 28 and the above-mentioned notch 30. In Figure 5, it can be seen that, in a variant, a plurality of adjacent sets can be provided at the ends of the ring 112. Three analogous male/female sets can be seen, comprising, respectively, a tongue 128A and a notch 130A, a tongue 128B and a notch 13OB, and a tongue 128C and a notch 13OC. Each of these sets is analogous to the set that is described above with reference to Figure 3, and thus includes two contact tabs, e.g. 132A and 132B, two deflection setbacks, e.g. 134A and 134B, disposed on those sides of the tabs that are opposite from the notch, and two nicks 136A and 136B analogous to the above-described nicks 36A and 36B.
The free edge 112A of the ring 112 that is equipped with the female shaped portions is situated on a line 1

parallel to the axis about which the sleeve is looped back on itself, i.e. the free ends of the tabs are situated on said line, as are the free ends of all of the portions formed between the notches and the deflection setbacks.
Intermediate tabs 113, locally bringing the free end 112A onto the line 1 are provided between the deflection setbacks of two adjacent sets.
Similarly, the free edge 112B of the ring on which the tongues 128A, 128B, and 128C are situated is situated on a line 1' parallel to the same axis, relative to which only the tongues project.
Naturally, although the example of Figure 5 shows three male/female sets, a different number of sets could be provided.
However, it is advantageous, in order to balance the forces exerted on the ring during tightening, for said ring to be symmetrical about its midplane PS perpendicular to its loop axis A. Thus, in Figure 2, the tongue 28 and the notch 30 are centered relative to such a plane PS and the central male/female set 128B/130B of Figure 5 is also centered on such a plane PS.
In Figure 5, it should be noted that, between two adjacent tongues, e.g. 128A and 128B, a notch 127 is provided into which two contact tabs penetrate, e.g. tabs 132A and 133B belonging to the two adjacent male/female sets.
Precisely, with reference to Figure 6, it can be understood that, in a variant of the invention, it is possible to choose to make provision for the female shaped portion to comprise a notch 230 and for the male shaped portion to comprise two side contact tabs, respectively 232A and 232B, suitable for penetrating into said notch. In which case, the contact engagement is established between the "outside" contact edges 23OA and 230B of the tabs 232A and 232B and "inside" contact edges 228A and 228B of the notch 230. In which case, the male

shaped portion of the male/female set in question thus includes the two above-mentioned tabs 232A and 232B. Figure 6 shows that the width 1230 of the notch, as measured parallel to the axis of a bearing A of the ring, and the gap 1230 between the contact edges 230A and 230B decrease going in the direction S in which the tabs penetrate into the notch.
The male shaped portion in Figure 6 further comprises a central tab 231 which is disposed between the contact tabs 232A and 232B while being spaced apart therefrom by deflection setbacks, respectively 234A and 234B. It is possible to omit the central tab 231A and merely to make provision such that, on deflecting, the tabs 232A and 232A deflect into the space formed between them. However, as explained above, it is advantageous for the free edges of the two ends of the ring to come as close together as possible, so that it is desirable, by means of the tab 231, to bring the free end of the male shaped portion locally to the level of the free ends of the tabs 232A and 232B.
In Figure 6, the deflection setbacks are provided with slanting nicks, respectively 236A and 236B which are situated in the vicinities of the contact tabs 232A and 232B. Said nicks converge going in the direction in which the male shaped portion penetrates into the female shaped portion, for facilitating deflection of the tabs as indicated by the arrows P', in the above-mentioned deflection setbacks.
The variant of Figure 7 uses contact tabs both for its male shaped portion and for its female shaped portion.
In this variant, the male shaped portion is identical to the male shaped portion of Figure 6 and its various component elements are designated by the same references as in that figure. The female shaped portion is identical to the female shaped portion of Figure 3, and its various consecutive elements are identified by the same references as in that Figure. Thus, when the male shaped portion penetrates further into the female shaped portion, the tabs 232A and 232B of the male shaped portion tend to deflect into the setbacks 234A and 234B formed between them, on either side of the central tab 231, while the tabs 32A and 32b that define the notch 30 of the female shaped portion between them tend to deflect into the deflection setbacks 34A and 34B provided on either side of said tabs. The slanting nicks 36A, 36B, 236A and 236B facilitate this deflection.

CLAIMS
1. A device for coupling together in leaktight manner two
smooth tubes disposed end-to-end and having substantially
the same diameter, the device comprising a sleeve (10)
suitable for being disposed around the facing ends of the
two tubes, said sleeve being provided with means (11) for
enabling its diameter to be decreased under the action of
tightening means (22, 24), the device further comprising
a sealing ring (12, 112) suitable for being disposed
inside the sleeve (10) for the purpose of surrounding the
facing ends of the two tubes, said ring being constituted
by a strip looped back on itself and having two ends
(12A, 12B; 112A, 112B) suitable for coming into engagement contact, via at least one male/female set comprising a male shaped portion (28; 128A, 128B, 128C; 232A, 232B) suitable for being engaged in a female shaped portion (30; 130A, 130B, 130C; 230) when, with the ring being situated inside the sleeve (10), said sleeve is tightened around the facing ends of the tubes;
said device being characterized in that at least one of the male and female shaped portions of a male/female set has contact edges (30A, 30B; 230A, 230B) formed on contact tabs (32A, 32B; 132A, 132B; 232A, 232B), said tabs being suitable for deflecting in the direction facilitating penetration of the male shaped portion into the female shaped portion while the male shaped portion is engaging into the female shaped portion under the effect of the tightening.
2. A device according to claim 1, characterized in that
deflection setbacks (34A, 34B; 134A, 134B) are provided
on those sides of the contact tabs (32A, 32B; 132A, 132B)
that are opposite from the contact edges (30A, 3OB) .
3. A device according to claim 1 or claim 2,
characterized in that the contact tabs (32A, 32B; 132A,

132B) are connected to the end of the strip that carries them via nicked base portions (36A, 36B; 136A, 136B).
4. A device according to any one of claims 1 to 3,
characterized in that the male shaped portion of the
male/female set comprises a tongue (28; 128A) while the
female shaped portion of said set comprises a notch (30;
130A) defined between two contact tabs (32A, 32B; 132A,
132B), so that said tongue can penetrate into said notch,
and in that at least one of the transverse dimensions
constituted by the width (128) of the tongue and by the
width (130) of the notch decreases going in the direction
in which the tongue penetrates into the notch.
5. A device according to claim 4, characterized in that
deflection setbacks (34A, 34B; 134A, 134B) are provided
on the sides of the contact tabs (32A, 32B; 132A, 132B)
that are opposite from the notch (30; 130A).
6. A device according to claim 5, characterized in that
the deflection setbacks (34A, 34B; 134A, 134B) are
provided with slanting nicks (36A, 36B; 136A, 136B)
situated in the vicinity of the contact tabs (32A, 32B;
132A, 132B).
7. A device according to any one of claims 1 to 6,
characterized in that the female shaped portion of the
male/female set comprises a notch (230; 30) while the
male portion of said set comprises two side contact tabs
(232A, 232B) suitable for penetrating into said notch (230; 30), and in that at least one of the transverse dimensions constituted by the width (1230) of the notch and by the gap (e230) between the contact edges (230A; 23OB) of the contact tabs decreases going in the direction in which said tabs penetrate into said notch.

8. A device according to claim 7, characterized in that
said male shaped portion further comprises at least one
central tab (231) disposed between the contact tabs
(232A, 232B) while being spaced apart therefrom by
deflection setbacks (234A, 234B).
9. A device according to claim 7, characterized in that
the deflection setbacks (234A, 234B) are provided with
slanting nicks (236A, 236B) situated in the vicinities of
the contact tabs (232A, 232B).

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=UIV18GHGYGhD7eU5cijOyA==&loc=+mN2fYxnTC4l0fUd8W4CAA==

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Patent Number

272573

Indian Patent Application Number

8278/DELNP/2007

PG Journal Number

16/2016

Publication Date

15-Apr-2016

Grant Date

11-Apr-2016

Date of Filing

26-Oct-2007

Name of Patentee

ETABLISSEMENTS CAILLAU

Applicant Address

28 RUE ERNEST RENAN, 92130 ISSY LES MOULINEAUX, FRANCE.

Inventors:

#	Inventor's Name	Inventor's Address
1	NICOLAS RIGOLLET	87b Faubourg d’Orleans 41200 Romorantin Lanthenay, France
2	FABRICE PREVOT	BEZAINES - RUE DES NOUIES, 41130 SELLES SUS CHER, FRANCE.
3	TONY ROINTRU	654 ROUTE DE NEUNG, 41210 MARCILLY EN GAULT, FRANCE.

PCT International Classification Number

F16L 21/06

PCT International Application Number

PCT/FR2006/050342

PCT International Filing date

2006-04-12

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	0503690	2005-04-13	France