WO1998043010A1

WO1998043010A1 - Ring clamp for connecting two tubes

Info

Publication number: WO1998043010A1
Application number: PCT/FR1998/000613
Authority: WO
Inventors: Pascal Detable; Michel Andre
Original assignee: Etablissements Caillau
Priority date: 1997-03-26
Filing date: 1998-03-26
Publication date: 1998-10-01
Also published as: KR100393087B1; FR2761452B1; SE9903458D0; PL335977A1; DE19882234T1; CA2284861A1; PL186329B1; AR012180A1; FR2761452A1; SE519025C2; GB2338526B; SE9903458L; AU7051698A; BR9808091A; GB9922329D0; TW432177B; ES2172374A1; GB2338526A; KR20010005733A; HUP0002340A2

Abstract

The disclosed ring clamp has two half-shells (10, 20), each having a first extremity with a bearing pad (12, 22) extending outwards, as well as a second extremity equipped with one of the elements (14, 22) of the means of connection used to connect the two second extremities of the half-shells removably. The section of said half-shells is substantially U-shaped, with the branches of the 'U' extending towards the interior and having the capacity to operate in conjunction with the protruding support surfaces on the extremities of the two tubes. The clamp comprises a tightening screw (30), the post (32) of which traverses the pierced holes of the bearing pads (12, 22). The length (L) of the post is at least substantially equal to the radius (R) of the ring clamp when closed, and said post is inserted loosely into the holes of the bearing pads. The elements (14, 24) of said means of connection are designed to unite in order to bring together the second half-shell extremities, or to separate in order to maintain said extremities apart while the post of the screw remains in place in the holes of the bearing pads.

Description

CLAMP FOR CONNECTING TWO TUBES.

The present invention relates to a clamp for connecting two tubes, the opposite ends of which have bearing surfaces projecting from the cylindrical outer surface of said tubes, the collar comprising two half-shells each having a first end provided a support tab which extends outwards and has a hole, as well as a second end provided with one of the elements of assembly means intended to removably assemble said second ends of the half shells, said half-shells having, in their main part, a substantially U-shaped section, the branches of which extend inwards and are able to cooperate with said bearing surfaces of the two tubes, the collar comprising a clamping screw, able to cooperate with the support legs and whose rod passes through the holes of the latter.

Collars of this type are known from patents US-A-3,014,259 and US-A-3,964,773. In these collars, the assembly means in fact constitute a hinge which, after the connection of the two half-shells , keeps them permanently attached to each other. To put the collar in place around the bearing surfaces of the tubes, the two half-shells are spread apart using the hinge in order to arrange them around the bearing surfaces of the tubes to be connected and the two half-shells are brought together before Slide the screw into the holes in the support legs and tighten the collar. This maneuver is relatively easy but requires a manipulation consisting, once the half-shells are placed around the bearing surfaces of the tubes, to slide the screw in the support legs and to place the nut on the screw before tighten this nut. The operator having to handle the collar must therefore have three separate parts, namely the two half-shells assembled together, the screw and the nut. So finally it must assemble these three parts, which can be the cause of some loss of time, especially since relatively small parts such as the screw or nut may escape and fall on the ground. In addition, most of the time, the collars are delivered in the pre-assembled state in which the screw and nut are already in place. The operation consisting in installing the collar must be preceded by unscrewing the nut and / or releasing the screw outside the holes in the support legs.

Document GB-A-2 094 385 shows another collar of the aforementioned type, the means for assembling the two half-shells comprising a tab provided with a slot in which another tab engages. In this document, the assembly means are presented as a means of limiting the number of pieces of the collar.

GB-A-2 094 385 does not specify the method of mounting the collar around the object to be tightened, but it seems that the only possible mounting method is the same as that of the collars of US-A-3 014 259 and US-A-3,964,773.

The drawings of GB-A-2 094 385 show that the clamping screw is relatively long since the length of its rod seems to be slightly greater than the radius of the collar in the tightened state. However, no particular comment is made on this subject and the length of the screw shown on the drawings has no technical justification.

The invention applies to a collar of the aforementioned type, the screw rod of which has a length of the same order of magnitude as the radius of the collar when tight. It aims to further simplify the positioning of the collar and to avoid the manipulation of several separate parts.

This object is achieved thanks to the fact that the rod of the screw is loosely mounted in the holes of the support legs, a clearance being made in these holes, around said rod and that the elements of the assembly means are capable of be assembled to assemble the second ends of the half-shells or separated to separate said second ends, even when the screw rod is in place in the holes in the support legs.

We understand that these provisions allow to completely pre-assemble the various components of the collar by passing the rod of the screw through the holes in the support legs and only partially screwing the nut, which remains disposed in the vicinity of the one end of the screw rod. Conventionally, the necklace is delivered in this pre-assembled state. To put the collar in place, it is enough to separate the second ends of the half-shells by disengaging the assembly means and, by playing on the length of the rod of the screw and on the play which exists in the holes in the support legs around this rod, to arrange the two half-shells one after the other around the support surfaces of the tubes, then to assemble the second ends of the front half-shells tighten the collar normally, using the screw and nut. These manipulations are extremely simple and there is no risk of losing any of the pieces of the collar during its installation.

We choose the length of the screw rod of the same order of magnitude as the radius of the clamp in the tightened state (this is the internal radius, measured from the internal faces of the half-shells) because such a length, combined with the presence of play between the screw rod and the holes in which it is inserted, is sufficient to allow the installation of the collar without removing the screw.

For example, for a necklace with a radius between 25 and 40 mm and whose height of the branches of the U is substantially equal to 5 mm, a screw whose rod measures 45 mm (its length is therefore slightly greater than the radius of the necklace) , combined with a clearance of the order of 0.5 to 1.5 mm between the screw rod and the holes in which it is inserted. For necklaces with higher spokes, of the order of 45 to 50 mm, the height of the branches of the U remaining substantially equal to 5 mm, a length of rod of the order of 45 mm (substantially equal to the radius) is also suitable, combined at substantially the same clearance. In fact, the length of rod required depends on the ratio between the radius of the collar and the height of the branches of the V. For conventional necklaces, for which the height of the branches is greater, a length of one will be required. little greater than the radius.

In general, a length of rod between one and two times the radius of the collar in the tight state, combined with a play of a few tenths of a millimeter at 1 or 2mm from the rod in the bores allows the establishment of the collar without remove the screw. It should be noted that, to avoid that the tightening of the nut requires a large number of turns, it is preferable to ensure that the length of the rod is at most of the order of one and a half times the radius of the collar in the tight state. Advantageously, the assembly means comprise a first ear, located at the second end of a first half-shell, projecting radially outward radially from the outer periphery of said first half-shell and having a free end curved inward to form a hook, as well as a second ear, located at the second end of the second half-shell, projecting substantially radially outwards from the external periphery of said second half-shell and able to cooperate with said hook.

In this way, the assembly means are produced in a simple and economical manner. In addition, insofar as they are located radially projecting from the current periphery of the collar, they can be engaged or disengaged without it being necessary to tilt the two half-shells very strongly, one with respect to the other.

The invention will be clearly understood and its advantages will appear better on reading the detailed description which follows, of an embodiment shown by way of nonlimiting example. The description refers to the accompanying drawings in which:

FIG. 1 is an elevation view of a collar according to the invention,

FIG. 2 is a partial view along arrow II of FIG. 1, - FIG. 3 is a section along the line III-III of FIG. 1,

FIG. 4 is a partial view along arrow IV of FIG. 1,

FIGS. 5 to 8 illustrate four successive phases of the positioning of the collar on the ends of two tubes to be assembled,

FIG. 9 is a view similar to FIG. 1, showing a variant of the collar,

FIG. 10 is a partial section along the line X-X in FIG. 9, and

- Figure 11 is a section along line XI-XI of Figure 10.

The collar of FIG. 1 comprises two half-shells 10 and 20 which each have a first end provided with a support lug, respectively 12 and 22, as well as a second end provided with an assembly element, respectively 14 and 24. Considered jointly, the elements 14 and 24 constitute assembly means which make it possible to removably assemble the second ends of the half-shells 10 and 20. The support legs 12 and 22 extend towards the outside of the necklace, that is to say they move away from the center of the collar from the current periphery of the latter. The two legs 12 and 22 are parallel and extend generally in a radial plane of the collar. The rod 32 of a screw 30 passes through two aligned bores 12 'and 14', respectively formed in the support tabs 12 and 22.

The two half-shells are made from a metal strip wound on substantially 1/2 turn and suitably hardened.

For tightening the collar, the second ends of the half-shells 10 and 20 are assembled by means of assembly elements 14 and 24 and the nut 34 for tightening the screw is actuated so as to bring one of the other the two support legs 12 and 22. The head 36 of the screw cooperates with one of the support legs (12) while its nut 34 cooperates, directly or indirectly, with the other support leg (22). Note that in the example shown, a washer 38 is fixed to the support tab 22, the end 38a of this washer which is opposite to the support tab 12 serving as a stop for the nut during tightening. For fixing, this washer is simply engaged in the bore 14 'of the tab 22 and is riveted to the latter by deformation of its end 38b opposite the end 38a above. The connecting element 14 forms a first ear which is situated at the second end of one of the half-shells (10). This first ear projects radially outwards from the collar from the external periphery of this half-shell and has a free end 14a which is curved inwards to form a hook. The connecting element 24 forms a second ear which is situated at the second end of the other half-shell (20), which projects substantially radially outwards from the external periphery of this second shell and which is able to cooperate with the hook 14a by engaging in the hollow of the latter. The two ears 14 and 24 are located in radial projection relative to the current periphery of the collar. The height h of the ear 24, measured from the free edge of the hook (engagement height), is low, conventionally of the order of 2 to 5 mm, so that the hook 14 can be engaged on the ear without it being necessary to move the half-shell 10 too far towards the outside of the collar relative to the half-shell 20. In addition, it will be noted that the width I of the bottom of the hook is greater than the thickness e of ear 24 (substantially equal to one and a half times this thickness) to allow easy engagement of the ear 24 in the hook 14a by a relative inclination of the two half-shells. For fixing the collar, the assembly means function as a hinge around which the half-shells pivot when the nut is tightened on the screw.

As can be seen in the section of FIG. 3, the main parts of the half-shells have a substantially U-shaped section having a bottom 40 and two branches 41 and 42. In FIG. 3, the lines are also shown in fine lines. ends of two tubes 44 and 46 provided with bulges 44a and 46a on which are placed the half-shells of the collar. More specifically, the bulges comprise bearing surfaces, respectively 44b and 46b with which the branches 41 and 42 of the U which cooperate form the section of the half-shells so as to clamp the tubes tightly against one another .

The bearing surfaces 44b and 46b are in fact advantageously frustoconical, as are the branches 41 and 42, so that the tightening of the collar effectively tends to bring the two tubes closer to one another. By indicating that the section of the half-shells has the overall shape of a U, we wish to underline the fact that the collar presents, on the major part of its circumference, two flanges or flanks 16 and 18 formed by the branches of the U , generally symmetrical with respect to its median plane P and able to cooperate with the bearing surfaces of the bulges formed on the ends of the tubes. The flat part 40 forming the base of the U, and delimiting the external periphery of the collar, can be more or less long depending on the dimensions of these bulges. It can even be practically non-existent, in which case the section of the necklace would rather have the shape of a V.

The partial view of Figure 2 shows that the ears 14 and 24 are formed by deformations of the ends of the half-shells, for example obtained by stamping. These are raised radially; the cheeks 16 and 18 are also raised and contribute to the formation of the ears.

In the extreme, one could choose to use a screw constituted by a simple threaded rod tightened by means of two nuts cooperating respectively with each of the support legs 12 and 22. Preferably, as shown in Figure 1, rather uses a screw whose head 36 is integral with the rod, only the nut 34 to be manipulated for tightening. In this case, the support tab 12 which cooperates with the head 36 of the screw is advantageously equipped with means to prevent the rotation of the latter.

More precisely, as can be seen in FIG. 4, the head of the screw has at least one flat 36a (for example, quite simply a polygonal head is chosen). The support tab 12 with which the head of the screw cooperates, has a flange 12a which extends in the direction away from the other support flap 22. This flange defines a housing 13 for the head 36 of the screw (it extends for example over a length slightly greater than the thickness of this head). On at least part of its contour, the rim 12a has a substantially flat portion 13a, able to cooperate with the aforementioned flat 36a. Simply, if we choose a polygonal head, we endow the rim, in its part farthest from the current external periphery of the collar, with a similar polygonal shape whose sides are slightly longer than those of the screw, so as to preserve a slight clearance f between the head of the screw and the flange. Thus, the head 36 is not completely blocked, which, as will be seen below, allows a slight relative movement of the screw and the tab 12, but the head of the screw cannot rotate inside. of the housing 13. To keep the head inside this housing, the latter advantageously has a wall element 15 which partially closes it on the side opposite to the support tab 22. This wall element 15, constituted for example by an extension of the rim 12a folded substantially at a right angle, is produced so as not to prevent the relative movement of the screw and the support tab 12.

The rim 12a of the lug 12, as well as a similar rim 22a of the lug 22, also constitute means for stiffening these lugs preventing their folding when the collar is tightened.

In Figure 1, there is designated by the reference j1 the clearance which is preserved between the rod of the screw and the bore 12 'of the lug 12 and, by the reference j2, the clearance which is formed between the rod of the screw and the internal periphery of the washer 38. It should be noted that if the washer 38 was absent, such a clearance j2 would be provided between the bore 14 'of the support tab 22 and the rod of the screw.

The latter is loosely mounted in the holes, which means that the clearances j1 and j2 are sufficient to allow movement of the two half-shells relative to the screw in the direction of the arrows F1 and F2 indicated in FIG. 6, when the assembly elements 14 and 24 are disengaged. To further facilitate this movement, the internal periphery of the washer 38 is frustoconical and widens towards its end 38a. The angular movement of the two half-shells relative to the rod of the screw according to F1 and F2 necessary for attachment depends on the height of the branches 41 and 42 of the U (FIG. 3) and, more precisely, on the height of overlap between branches 41 and 42, and the bulges

44a and 46a. This angular movement is conditioned by the games j1 and j2.

In Figure 1, we see that the length L of the screw rod is at least substantially equal to the radius R of the collar in the tight state. This arrangement makes it possible that, when the nut is at the end of the screw rod, in its position indicated in broken lines, the first ends of the half-shells 10 and 20 can be separated one on the other by sliding along the rod over a sufficient length (substantially equal to the length L minus the thickness of the nut 34).

To set up the collar, which is initially pre-assembled (that is to say that the screw is previously deposited in the holes of the support legs), the second ends of the half-shells 10 are firstly moved aside and 20 by disengaging the assembly means 14 and 24. Then the first ends of the half-shells are moved aside by translating them one relative to the other along the rod 32 of the screw. It should be noted that the nut is then substantially at the end of the screw, in the position shown in broken lines in Figure 1, to have a maximum translation amplitude. Then, the two half-shells are pivoted relative to each other around the screw rod and a first half-shell is placed on the bearing surfaces of the tubes. This achieves the situation shown in Figure 5. On this occasion, it is preferably the half-shell 20, that which includes the ear 24, which is placed on the bulges of the tubes, the other half-shell 10 being pivoted substantially at a right angle (perpendicular to the plane of the figure).

Then, keeping the half-shells apart, the second half-shell is folded down (in this case, the half-shell 10) to bring it back into the plane of the first (20). On this occasion, the second end of the half-shell 10 passes without difficulty the obstacle constituted by the tubes and their bulges, thanks to the fact that the length of the rod is sufficient. One can also take advantage of a slight angular movement of the half-shell 10 relative to the half-shell 20 in the opposite direction to the arrow F2.

From this position, the second ends of the half-shells are assembled by engaging the assembly elements 14 and 24. On this occasion, one also takes advantage of the deflection capacity of the two half-shells, one with respect to the 'other related to the length of the rod and its loose mounting in the holes of the support legs. In addition, the assembly elements advantageously having the shape of the ears 14 and 24 previously mentioned, they can be engaged, without it being necessary to "open" the first ends of the half-shells too much. FIG. 7 shows the attachment phase in which, using the travel in the direction of the arrows F1 and F2, the hook 14 passes under the ear 24.

Finally, after attachment, it suffices to bring the first ends of the half-shells together by a relative translation of the latter along the screw, so as also to have the half-shell 10 on the bearing surfaces of the tubes. During this relative translational movement, the assembly means are used as a hinge. We are then in the position shown in Figure 8, from which it is enough to screw the nut to tighten the collar using the screw. In FIGS. 9 and 10, elements similar to FIGS. 1 to 8 are given the same references increased by 100.

The two half-shells 1 10 and 120 have a U-shaped section, the branches of which have edges 1 10a, 120a slightly raised to extend axially, as shown in FIG. 1 1 for the half-shell 1 10. The support legs 112 and 122 are reinforced by flanges or cheeks 112a, 122a which extend in the continuity of the branches of the U formed by the sections of the half-shells, without reversing these branches unlike the flanges 12a and 22a of Figure 1. Therefore, in Figure 9, the head 136 of the screw 130 is not disposed in a housing. To prevent the screw from turning in the bore 112 'of the support leg 112, the region of the rod 132 of the screw immediately adjacent to the head 136 has a non-circular collar 133 (for example a square collar or a bead having a flat) and the hole 112 'has a shape with which this collar can come into engagement. As can be seen in FIG. 10, the hole 112 'is slightly larger than the collar 133 so that the play j1 is preserved between the rod of the screw and the edges of the hole 114'.

Claims

1. Clamp for the connection of two tubes (44, 46) whose opposite ends have bearing surfaces (44b, 46b) projecting from the cylindrical outer surface of said tubes, the collar comprising two half shells (10, 20; 110, 120) each having a first end provided with a support tab (12, 22; 112, 122) which extends outwards and has a hole (12 ', 14' ; 112 ', 114'), as well as a second end provided with one of the elements (14, 24; 114, 124) of assembly means intended to removably assemble said second ends of the half-shells, said half-shells having, in their current part, a substantially U-shaped section, the branches of which extend inward and are able to cooperate with said bearing surfaces of the two tubes, the collar comprising a clamping screw (30; 130), able to cooperate with the support legs and whose rod (32; 132) passes through the holes of the latter, the rod (32; 132) of the screw (30; 130) having a length (L) of the same order of magnitude as the radius (R) of the collar in the tightened state, characterized in that said rod is loosely mounted in the bores (12 ' , 14 '; 112', 114 ') of the support legs, a clearance (j1, j2) being provided in said holes around the rod (32; 132) of the screw (30; 130) and in that the elements (14, 24; 114, 124) of said assembly means are capable of being joined to assemble the second ends of the half-shells (10, 20; 110, 120) or separated to separate said second ends, even though the rod (32; 132) of the screw (30; 130) is in place in the holes in the support legs.

2. Collar according to claim 1, characterized in that the assembly means comprise a first ear (14; 114), located at the second end of a first half-shell (10; 110), projecting substantially radially towards the outside from the outer periphery of said first half-shell (10; 110) and having a free end (14a) curved inward to form a hook, as well as a second ear (24; 124), located at the second end of the second half-shell (20; 120), making it substantially radially projecting outwards from the outer periphery of said second half-shell and able to cooperate with said hook (14a).

3. Collar according to claim 1 or 2, characterized in that, the screw having a head (36; 136) being integral with its rod (32; 132), it comprises means (13a, 36a; 133, 112 ') to prevent rotation of the screw (30; 130) relative to the bore (12 ', 112') of the support tab (12; 112) with which the head (36; 136) of the screw cooperates.

4. Collar according to claim 3, characterized in that, the head (36) of the screw having at least one flat (36a), the first support tab (12) has a flange (12a), extending in the direction going away from the second support leg, delimiting a housing (13) for the head (36) of the screw (30) and having, at least over part of its outline, a portion (13a) substantially flat capable of cooperating with said flat.

5. Collar according to claim 4, characterized in that the housing (13) has a wall element (15) which at least partially closes said housing on the side opposite to the second support tab (20) and maintains the head. the screw inside this housing.

6. Collar according to claim 3, characterized in that the rod (132) of the screw (130) comprises a non-circular collar (133) adjacent to the head

(136) of said screw and in that the bore (112 ') of the support tab (112) with which the head of the screw cooperates has a shape allowing the collar (133) to engage against the edge of said drilling (112 ').

7. Collar according to any one of claims 1 to 6, characterized in that the bore of at least one (22) of the support legs is equipped with a washer (38), fixed to said leg d 'support and whose end (38a) opposite the other support tab (12) forms a stop for a nut (34) for tightening the screw (30).

8. Method for fitting a collar according to any one of claims 1 to 7, characterized in that, the screw (30) being previously disposed in the holes in the support tabs (12, 22), the second ends of the half-shells (10, 20) are moved aside by disengaging the assembly means (14, 24), the first ends of the half-shells are moved aside by a relative translation of said first ends along the rod (32 ) of the screw, the two half-shells are pivoted relative to each other around the rod of the screw, a first half-shell (20) is placed on the bearing surfaces of the tubes, keeping the half-shells apart, the second half-shell (10) is folded down to bring it back into the plane of the first, the second ends (14, 24) of the half-shells, the first ends of the half-shells are brought together by a relative translation along the rod (32) of the screw so as to arrange the second half-shell on the surfaces of support the tubes and tighten the collar using the screw (30).