FR2553154A1 - Clamping collar with spring - Google Patents

Abstract

The subject of the present invention is a clamping collar 1 consisting of a wire or thin strip made of an elastic material forming at least one ring and of a coiled compression spring 3, characterised in that each strand 6 beyond the circumference formed by the ring is bent backwards in order to form folds upon which the spring rests in the clamping position, in that the end of the strands which is surrounded by the spring 3 is itself bent over in order to form a temporary fold 5 upon which the spring 3 rests in the compressed position and in that the temporary fold 5 has a weakened zone which allows it to break and allows the spring 3 to pass into the clamping position.

Description

 The present invention relates to clamps intended to fix a more or less flexible tubular element on a more or less rigid tubular element and to ensure a perfect seal between these elements.

 There are hose clamps formed by a wire, generally metallic, forming one or more rings, the opposite ends forming curved turns so as to be able to hang on one another.

These necklaces have several disadvantages
- They must have a dimension very precisely adapted to that of the tubular element on which they are mounted, this element must itself have very high dimensional accuracy
- they do not make it possible to compensate for any settlement of 1 flexible tubular element: aging, expansion and thermal contractions, because they do not have any compensation means;
- They have a tightening discontinuity to the right of the point of attachment of the ends, with risk of pinching of the flexible tubular element and risk of leakage;
- they are rarely removable and reassemblable.

 There are also Clamps formed by a wire forming one or more rings, or by a cut strip, the ends of which cross without allowing the moon to be hooked on another.

the ring (s) themselves having an elasticity intended to compensate for the settlement of the tubular element.

These necklaces have several drawbacks
- They must have a dimension precisely adapted to that of 1 tubular element on which they are mounted and this element must itself have great dimensional accuracy
- in order to compensate for any settlement of the tubular element, they must allow. during assembly. an abnormally high tightening, which makes this operation more difficult and imposes locally very strong stresses liable to damage both of the tubular elements
- they present significant irregularities in tightening and stresses from one point to another of the circumference, the tightening being the strongest in the two diametrically opposite symmetrical zones and the weakest in the zone of crossing of the ends while the stresses in the wire are highest in the zone opposite the crossing of the ends.

 There are also clamps formed by one or more wires or by a strip made of metallic or plastic material, the opposite ends, crossing or not, being held by a rigid closing device; this device, adjusted during assembly of these collars, allows in some cases a later adjustment.

These collars have one advantage and several disadvantages
The advantage
- They allow dimensional adjustment during assembly, and possibly later, making it possible to adapt to the initial dimension of the tubular element on which they are mounted.

The inconvenients
- they generally have one or more tightening discontinuities at right angles to or near the closing device
- after assembly, the metal collars thus produced constitute around the tubular element a rigid hoop, the latter - cannot compensate for any settlement of the flexible tubular element, the sealing qualities are thus generally provisional
- in anticipation of the subsequent settlement of the flexible tubular element, these collars must be mounted with an abnormally high closing force; generally this results in damage to both of the tubular elements
- After assembly, the collars whose ring is made of plastic material are subject to creep elongations of the material; this development, combined with the compaction of the flexible tubular element, generally results in a rapid loss of the sealing qualities;
- such collars, made of plastic material. generally have poor resistance to certain products to which they may be exposed; they are generally sensitive to temperature variations; they are most often flammable or lose their tightening qualities on contact with a flame.

The present invention aims to provide clamps to overcome the drawbacks of the prior art, in particular by increasing the possibilities of elastic deformation outside. the ring in order to allow greater compensation for the settlement or expansion of the flexible tubular element, in order also to allow a wider adaptation of a given collar to tubular elements of different dimensions and thus reduce the number of models of necklaces covering a given range of diameter
The present invention further aims to allow
- to prestress before assembly the ConfiT elastic guration external to the ring and to obtain during assembly an instantaneous triggering of this elastic preload, which preserves subsequent possibilities of compensation for compaction or expansion of the flexible tubular element
- To clearly visualize the fact that the collar has been correctly mounted and provides predetermined tightening characteristics regardless of the more or less attentive care provided during assembly.

 To this end, the subject of the present invention is a hose clamp consisting of a wire or a strip of elastic material forming at least one ring and of a compression compression spring, characterized in that each strand beyond the circumference formed by the ring is folded back to form folds on the squels the spring rests in the clamping position, in that the end of the strands which is surrounded by the spring is itself folded to form a provisional fold on which the spring rests in the compressed position and in that the provisional fold has a weakening zone allowing its ru-pture and the passage of the spring in position # clamping.

The invention will be explained below in more detail with reference to the accompanying drawings in which
Figure 1 is a perspective view of a collar according to the invention in the clamping position.

FIG. 2 is a front sectional view of the collar of FIG. 1 in the armed position,
FIG. 3 is a detailed view of FIG. 2.

FIG. 4 is a perspective view of another collar according to the invention in the clamping position,
FIG. 5 is a sectional view of the collar of FIG. 4, and
FIG. 6 is a perspective view of the ring of the collar of FIGS. 4 and 5, in the very open position for clarity of the drawing,
The collar 1 shown in FIGS. 1 to 3 is made up of a wire of elastic material forming a ring 2 and of a compression coil spring 3.

 One of the strands constituting the end of the ring 2 forms a first fold 4 in return with respect to the ring and a second fold 5 in the opposite direction to the first and separated from the latter by a part 6 slightly bent towards 1 ring 2.

 As shown in FIG. 2, when the collar is in the armed position, that is to say that the compression spring is in the highly compressed position. all of the turns of the spring are crossed by the strand 6 and the extreme turns 7 and 8 of the spring 3 come to bear respectively inside the folds 4 and 5.

 The strand 9 constituting the other end of the ring 2, also forms, slightly beyond the second fold 5 of the other strand, a return fold 10.

The end 11 of this strand 9 is inserted inside the end turn 8 of the spring 3. A play exists between the end turn 8 and the fold 10. This play is intended to facilitate the mounting of the collar on the elements. tubular elements.

 As shown in Figure 3 the fold 5 has on the outside a notch 12 constituting a local weakening.

 This local weakening of the fold 5 allows during assembly to break the wire at the notch 12, for example by unfolding using pliers. This break allows the extreme turn 8 to pass from the blocking position against the fold 5 to a blocking position against the fold 10.

 Only part of the elastic work of the compressed spring is then released, so that the spring then exerts the clamping force on the collar and makes it possible to compensate for the subsequent compaction of the flexible tubular element.

 Such a collar can be applied to many watertight assemblies by the particular ease that it provides of comprising two elements whose dimensioning is independent.

 In addition, the presence before mounting, then the absence, of the broken end when triggered, allows an easy visual check of the correct mounting without it being necessary to perform any adjustment.

 Finally, the compression spring can easily be made of various materials. especially metallic. elastomers or composites.

 The collar 13 represented in FIGS. 4 to 6 consists of a wire made of elastic material folded into a U forming two rings 14 and 15 and of a compression coil spring 16.

 The connection zone of the 2 rings 14 and 15 is folded outwards slightly back with respect to the rings 14 and 15 so as to form a retaining spoiler 17.

 As shown in FIG. 5, the retaining spoiler 17 is inserted between two turns of the compression spring 16.

 At the other end of the rings 14 and 15, slightly beyond the circumference formed by these rings. the wire is folded back towards the outside to form strands, respectively 18,19, slightly bent towards the rings and connected to these rings by folds 20 and 21 respectively, the strand 19 being shorter than the strand 18 .

 The strand 18 ends with a part 22 which is folded back by forming a fold 23.

 As in the case of the collar shown in FIGS. 1 to 3, the fold 23 has on the outside a notch 24 constituting a local weakening, allowing the end portion 22 of the strand 18 to break.

 In the armed position of the collar, the spring is supported by its extreme turns 25 and 26. on the one hand inside the folds 20 and 21 and on the other hand inside the fold 23.

 When mounting the clamp. the end part 22 of the strand 18 is broken, for example by unfolding it using pliers. The compression spring 16 is then triggered while remaining partially compressed between the folds 20 and 21 and the spoiler 17, allowing the tubular assembly to be tightened and compensation for its subsequent compaction.

 The extreme turn 26 which is released during the rupture of the end part 22 further comprises an end 27 folded towards the center allowing the spring 16 to rotate. While the other end turn 25 closes on itself forming a complete ring which can rotate in folds 20 and 21.

This allows, if the tightening proves to be insufficient, to reinforce it by increasing the number of turns compressed between the spoiler 17 and the folds 20 and 21 by rotation of the spring.

 The particular conformation of the collar shown in FIGS. 4 to 6 thus makes it possible to combine the advantage of an instantaneous and very simple assembly, the advantage of a double-compressing ring better the flexible tubular element and finally 1 "advantage of be able to easily perform post-adjustment of the tightening if necessary.

Claims (4)

 1- Hose clamp (1; 13) made up  of a wire or a strip of elastic material forming  at least one ring and one spring (3; 16) of com  roll pressure, characterized in that each bri  (6. 9; 17, 18, 19) beyond the formed circumference  by 1 ring is folded back to form folds  (4, 10; 17, 20, 21) on which the spring rests in the clamping position, in that the end of the end -of  strands which is surrounded by the spring (3; 16) is  itself folded to form a fold (5; 23) provi  evening on which the spring (3; 16) rests in.  compressed and in that the provisional fold (5  23) has a weakening zone allowing its  rupture and passage of the spring (3; 16) in position  Clamping.  2- clamp according to claim  1, characterized in that the weakening zone of the  temporary fold (5; 23) includes a notch (12  24) disposed at the end of said fold (5; 23).  3- Clamp according to any one  of claims 1 and 2 characterized in that the wire  is folded in half to form two rings, (14, 15).  to form said provisional fold (23).  21) on which the spring (16) rests and in that the end of one of these strands is itself folded back  strands (18, 19) connected to these rings by folds (20,  circumference formed by the rings, to form  rings (14, 15) the wire is folded beyond the  in the clamping position, in that at the other ends  return to form a retaining spoiler (17) on which an intermediate turn of the spring (16) rests  the connection zone of the two rings being folded in  4- clamp according to claim 3, characterized in that the compression spring comprises an end turn (25) closing on itself while the other end turn (26) includes a folded end (27) for rotating the spring.