WO2001063168A1

WO2001063168A1 - Connection assembly comprising at its end a bent cylindrical rigid tube end piece and method for making same

Info

Publication number: WO2001063168A1
Application number: PCT/FR2001/000548
Authority: WO
Inventors: Daniel Baron
Original assignee: Manuli Auto France
Priority date: 2000-02-23
Filing date: 2001-02-23
Publication date: 2001-08-30
Also published as: FR2805330A1; ITMI20000441A1; AR027553A1; FR2805330B1; IT1317122B1; ITMI20000441A0; DE20180339U1

Abstract

The invention concerns a connection assembly (1), and a corresponding method for making same, comprising at least a cylindrical rigid tube end piece (2) to be connected to a piece provided with an orifice adapted to co-operate with the end of said end piece. The assembly comprises a clamping flange (22) perforated right through with at least a bore for passing through the end of said end piece and means (26) for fixing the flange onto the piece. The assembly further comprises at least a bracket (5) abutted on the flange, forming a roller bending the bent end of the tube end piece, with a bending radius R not greater than 1.2 times the external diameter D of said tube, said end piece being bent at its end (3) in situ by bending on the bracket.

Description

CONNECTION ASSEMBLY COMPRISING A RIGID CYLINDRICAL TUBE END BENT AT ITS END, AND METHOD FOR MANUFACTURING SUCH AN ASSEMBLY

The present invention relates to a connection assembly comprising an end of a bent cylindrical rigid tube, for connection with a part provided with an opening suitable for cooperating with the end of the end, a clamping flange pierced right through by a passage bore at the end of the end piece, means for blocking the tube end piece on the flange and means for fixing the flange on the part.

It also relates to a method of manufacturing such an assembly.

It finds a particularly important although not exclusive application in the field of connections forming an angle of 90 °, used in automobile air conditioning circuits. Elbow connection systems are already known. The latter are generally brazed, that is to say welded, which involves a significant manufacturing cost.

In addition, such brazing does not allow a multiple choice of orientations between tube and fixing flange.

Elbow systems are also known with radii of curvature of the elbow (taken from the neutral fiber) of between 1.5 and 2 times the external diameter of the tube.

These known systems generate too much space in height and / or side, which can hinder or even prevent the use of elbows in spaces of limited volume, such as those encountered in air conditioning installations of motor cars.

There is also known (US-A-5, 853, 201) a system with 5 elbow tubes with small radius of curvature. The tube is formed by extrusion, then the elbow tube is fixed in a fixing piece. Such a system is fragile, poorly suited to different orientations, and difficult to assemble.

10 The present invention aims to provide a connection assembly that better meets those previously known to the requirements of the practice, in particular in that it allows the use of a reduced size bend, in that it allows the ^{r r} several orientations in the plane between tube and flange, while using the same standardized elements for a lower overall cost.

The assembly is easier and quicker to manufacture although it requires tools

20 specific.

To this end, the present invention proposes in particular a connection assembly comprising an end of a rigid cylindrical tube for connection with a part provided with an opening suitable for cooperation

2J with the end of said end piece, a clamping flange pierced right through by at least one passage bore from the end of said end piece, means for longitudinally abutting the tube end piece on the flange, and means for fixing the flange to the part,

50 characterized in that it comprises at least one etπer in abutment on the flange, forming a bending roller of the bent end of the tube end, with a bending radius R less than or equal to of the order of 1 , 2 times the external diameter of said tube, said tube end being bent m located at its end by bending on said etπer.

By of the order of, is meant with an accuracy of ± 10%.

The bending radius R is the radius of the circle formed by the neutral fiber, that is to say corresponding to the curved axis of the bend tube.

Due to the manufacture of the assembly by bending in the roller, the tube thus bent is partly deformed and therefore slightly flattened at the external part of the elbow, due to the stretching of the metal. Advantageously, the stirrup is in one piece. In advantageous embodiments, use is made of one and / or the other of the following arrangements:

- The assembly includes two bending etπers respectively forming bending rollers of two tube end pieces, with bending radii R and R ', each of value less than or equal to around 1.2 times the respective external diameters D and D 'of said tubes;

- the bending radius is between 0.8 and 1.1 times the external diameter of the tube;

- The flange and the bracket are mounted free to rotate relative to each other.

Such an arrangement allows great adaptability during assembly; - the end of the tube is bent at 90 °; to constitute the longitudinal abutment means of the tube end piece on the flange, the end of said end piece includes a flange, by example formed by folding or stamping, or added and brazed or glued, and the flange has a recess or a flat in shape complementary to said flange and located towards said end; - The assembly includes means for indexing the caliper on the flange in at least two different positions.

The flange and the bracket are then locked in rotation relative to each other, which gives more rigidity to the connection;

- The indexing means are constituted by toothed rings of complementary shapes, located opposite, respectively integral for one of the periphery of the bore of the flange and for the other of the caliper.

Thus, when the stirrup is in abutment on the flange, the rings interpenetrate and are locked in rotation relative to one another;

- To constitute the indexing means, the cylindrical bore comprises at least four notches or grooves in the axial direction, distributed angularly regularly on the periphery of the bore, and the stirrup comprises lugs of shape complementary to said notches or grooves , with which they are able to fit together to block the flange in rotation relative to the caliper;

- To constitute the indexing means, the flange comprises an end part, pierced with the bore, the peripheral lateral side of which forms a toothed crown, and the stirrup comprises a portion provided with at least one lug in screw -has a clean screw as' insert in one or more notches of said ring gear to block the flange in rotation by report to the caliper when the latter is in abutment on the flange;

- to constitute the indexing means, one of the elements among the flange and the stirrup comprises at least two notches, two lugs and / or two flats and the other element comprises at least one lug, a notch or a flat of complementary shape to those of the opposite element, suitable for cooperating with one of said notches or one of said lugs or flats of said opposite element to block the flange in rotation relative to the caliper when the latter is in abutment on the flange;

- To constitute the indexing means, the flange comprises an end portion, pierced with the bore, the peripheral lateral side of which forms a cylindrical wall provided with at least two notches or two lugs, and the bracket comprises a wall directed towards the flange provided with at least one lug or a notch of shape complementary to those of the opposite flange;

- To constitute the means of indexing, the stirrup comprises at least two notches or two suitable flats to cooperate with a lug or a flat of the flange with which it fits; - the bracket comprises an upper branch provided with a tube guide chute and an elbow bore with said bending radius, arranged to allow bending of the bent end of the tube end piece towards the bore of the flange, and perpendicular to the chute, a lower branch for abutment and / or lateral indexing with the flange; - The chute has ribs for lateral locking of the tube in said chute;

- The assembly is provided with means for sealing the junction between the part and the tube end piece. The invention also provides a method of manufacturing an assembly as described above.

It further proposes a method of manufacturing a connection assembly between a rigid tube end piece and a part, said assembly comprising a clamping flange pierced right through by at least one bore for passage of the end of the tube and means for blocking the tube end piece on the flange, characterized in that: the end of the rigid tube end piece is bent at 90 ° with a bending radius less than or equal to a of the order of 1, 2 times the external diameter of the tube, in an etπer serving as a bending roller in abutment on the flange, said etπer and said flange having been previously introduced on the tube and a flange having been produced on the end of the end piece leaving at the tube a distal cylindrical part.

To make the connection with the part, sealing means are then put in place on the distal cylindrical part, and the flange, thus blocked with the tube and the stirrup, is fixed to the part.

Advantageously, the tube is introduced into the bore of the flange slightly in force. Also advantageously, a mandrel is used inside the end of the end of the tube during bending. In another advantageous embodiment, the flange is introduced until it is force-fitted onto the collar.

A very slight crushing action of the tube in the stirrup can also be carried out, when the assembly is approached.

A clamp system that takes up the lateral constraints can also be implemented during bending. In an advantageous embodiment, the bracket is provided with indexing means relative to the fixing flange, the end of the tube is placed in the bore of the flange according to the angular position of indexing retained from the flange relative to the stirrup, and when the collar of the tube is abutted on the flange this blocks the tube and its stirrup in said angular position of indexing determined relative to the flange.

Advantageously, the stirrup is made of plastic filled and / or obtained by injection.

The invention will be better understood on reading the embodiments described below and given by way of nonlimiting examples. The description refers to the accompanying drawings in which: - Figure 1 is a side perspective view of an etπer and a flange, separated from each other, according to a first embodiment of the invention.

- Figure 2 shows the flange and the bracket of Figure 1 after assembly, the bracket being in abutment on the flange.

- Figure 3 is a side sectional view of the bracket of Figure 1. - Figures 3A, 3B and 3C are respectively on the one hand the sectional views along IIIA-IIIA, and along IIIB-IIIB, and on the other hand a top view, of the caliper of Figure 3. - The Figure 4 is a top view of the flange of Figure 1.

- Figure 4A is a cross-sectional view along IVA-IVA of the flange of Figure 4.

- Figure 4B is an enlarged side view of the notches and practical recesses on the bore of the flange of Figure 4A.

- Figure 5 is a perspective view of a second embodiment of a bracket and a flange according to the invention, separated from one another. - Figure 6 shows the flange and the bracket of Figure 5 after assembly.

- Figure 7 is a perspective view, from below, of a third embodiment of an assembly according to the invention, with means of mdexing by external crown.

- Figure 8 is a perspective view from above of the assembly of Figure 7.

- Figure 9 is a perspective view from below of a fourth embodiment of an assembly according to the invention, showing another means of mdexing.

- Figure 10 is a perspective view from below, of a fifth embodiment of an assembly according to the invention, again showing a variant of the means of mdexing.

FIGS. 11 to 15 give the main steps for manufacturing an assembly with an elbow tube end, according to an embodiment of the invention. Figures 1 and 2 show a set 1 of connection between a tube end 2, for example aluminum bend at its end 3 with a bending radius R ≤ D, where D is the external diameter of the tube and a part (not shown ) provided with an opening suitable for cooperating with the end part 4 of the end 3.

More precisely, and also with reference to FIGS. 3 to 3C, the assembly 1 comprises a bracket 5 in the form of an angle, in one piece, at a right angle, for example made of aluminum or of thermoplastic, for example injected under pressure, provided a horizontal branch 6, one end 7 of which ends in a downward bevel, and the other vertical branch 8 forms a solid block, substantially parallelepipedic.

The branch 6 is traversed right through, in the longitudinal direction of the branch, by a parallelepipedal trough 9 in the open, provided in the upper part of its rectangular walls 10, respectively and vis-à-vis, of the flat longitudinal parts 11 protruding inwards, for wedging and guiding the tube 2.

The lower wall 12 located on the free side relative to the vertical branch, of the horizontal branch 6 of the angle iron, is pierced right through, with a bore 13 of the same diameter as the tube with which it cooperates frictionally, and whose internal shape is bent at 14, with an internal bending radius R≤D, corresponding to the external bending radius R of the tube mentioned above.

We have shown in FIG. 3B, the stirrup in cross section along IIIB-IIIB, perpendicular to the curved axis 15 of the tube, which gives a semicircular section 16 17 the ends of which are extended by parallel tangents 18. The lower wall 12 has a flat surface 19 provided with lugs 20 regularly distributed angularly, for example eight lugs, around the periphery 21 of the bore 13.

Each lug is substantially parallelepipedic or has a horizontal section in the shape of a dovetail and comprises a recess 20 ′ forming a step down from the lug.

FIG. 3C shows, diagrammatically, the stirrup in top view, the branch 8 being for example provided with a face 8 ′ slightly concave with a longitudinal lug 8 ″ for setting and / or guiding the flange during assembly.

With reference to Figures 1, 2, 4, 4A and 4B; the assembly 1 further comprises a flange 22, for example in sintered aluminum or in sintered steel (composed of metallic powder compressed with a binder), for example of oval horizontal section or of oblong shape, provided with a side of a part 23 pierced by the bore 24 for introducing the external part 4 of the end 3 of the tube 2, and on the other side on the one hand 25 cylindrical pierced with a cylindrical or oval bore 26, for passage of a bolt (not shown) for fixing on the part, and having a lower face 27, flat, arranged to be in abutment with the upper flat face of the part opposite (not shown).

The bore 24 comprises on its periphery 28 recesses 31 of shape complementary to that of the lugs 20, arranged angularly regularly, and opposite.

The recesses include a wide upper part 32 and a narrower lower part 33 open towards the center of the bore.

It is thus possible by rotating the stirrup 5 in rotation relative to the flange 22, before assembly, to precisely and angularly position the stirrup relative to the flange as shown in FIG. 2, the offsets of the recesses allowing positioning perfectly adjusted.

As for the tube end piece 2, it is frictionally introduced into the bore 13 of the stirrup 5 and then into the bore 24 of the flange.

The collar 29 for blocking the tube on the flange is then formed, for example by stamping, then the tube is bent in the stirrup with the radius of curvature of the bore, that is to say very short, the collar coming for example to be inserted in a recess 30 (cf. FIG. 4A).

The tube is then inserted between the enlarged parts 11, in the chute 9.

The assembly etπer / tube / bπde is then put in place on the part, the stirrup fitting with the flange in the position and with the desired angle δ.

Then, after the sealing means have been put in place, for example a double O-ring 34 in the form of an 8 elastomer extension, threaded onto the end piece 4, the assembly with the tube is fixed to the part in a known manner, for example by bolting. In the following, the same reference numbers are used to designate the same or similar elements.

FIGS. 5 and 6 show a second embodiment of flange 40 and bracket 41 with trough 8 and hanger bore 13 as described above, each comprising a ring gear, respectively 42 and 43 for joining and indexing the flange with the caliper opposite allowing a very large number of angles of orientation.

Figures 7, 8, 9 and 10 show other embodiments of the invention with external indexing of the bore. FIGS. 7 and 8 show a third embodiment of a flange 44 and a stirrup 45 according to the invention, said flange comprising an external toothed ring 50 on the external cylindrical wall of the portion 23 pierced with the bore, the stirrup comprising a lug 47 comprising for example three or four vertical teeth, suitable for wedging in the teeth of the crown opposite.

Figures 9 and 10 show other examples of external teeth for indexing.

Figure 9 shows a flange 48 with outer ring 49 with twelve rounded teeth 50 extending over the entire thickness of the flange 50, suitable for fitting with a single lug 51 belonging to the concave internal face 52 of the vertical branch 53 of the stirrup 54. Here again the sealing means are constituted by one or two O-rings 55.

Figure 10 shows a flange 56, with three rectangular notches 57 on the height of the flange, suitable for cooperating with the lug 58 of the stirrup 59.

We will now describe the operation of the process more particularly described with reference to FIGS. 11 to 15.

The tube 60 is placed in the bracket 61 and in the flange 62 with which it is blocked longitudinally for example by stamping

(collar 63), the end of the end piece projecting from the external face of the flange.

The bracket 61 is oriented relative to the flange in the desired angular position as a function of the mounting requirements.

Then the stirrup 61 provided with the tube 60 and the flange 62 opposite, is placed on a tool 65 for positioning the stirrup and the flange, of complementary shape and coming into abutment on the latter

(see figures 11 and 12)

A bending jaw 66 is then brought opposite the end 64 of the tube and a bending strip 67 is placed on the other side of the stirrup 61.

The jaw and the strip are then brought into contact (arrow 68) (see Figure 13) of the tube, then the strip-) pivots (arrow 69), (see Figure 14) around the part 65, for example by being guided by a rounded portion 70 of the stirrup, ending on either side with radial stops 71 and 72. The external part 73 of the tube 60 is then stretched or nut-hardened and the internal part 74 compressed or packed, the end piece being then hanger in the stirrup which serves as a bending roller. The end connection assembly 75 can then be removed from the tool (see FIG. 15). Note that the bending jaw and the tool guarantee the orientation of the flange and the caliper, the flange coming to be embedded in a specific housing guaranteeing the perfect orientation of the latter. The stirrup groove is used as a bending tool.

The bending strip is used to maintain the tube well during bending and to avoid ovalization of the tube. Finally a lateral thrust cylinder is provided to prevent the stirrup from opening during bending.

It will also be noted that the assembly according to the embodiment of the invention more particularly described here, which comprises two separate elements, namely a bracket in which the tube is clipped, and a flange, which allow short hangers, resist surprisingly at bending pressures despite reduced thicknesses.

In addition, the assembly unexpectedly resists vibrational stresses, even though the resistant part is not a single piece or monolithic.

Finally the stirrup and the bending tool as described make it possible to contain the ovalization of the tube and the section of the material in the stretched area of the elbow, which undergoes a reduction of only 0.1 to 0.2 mm.

An O-ring, or at 8 (not shown), is then added and the flange is fixed to the part (not shown) by tightening.

As is obvious and as also follows from the above, the present invention is not limited to the embodiments more particularly described. On the contrary, it embraces all the variants and in particular those where the assembly is only made of aluminum alloy, that or the indexing means are different, that or the flange comprises a recess in which fits partly, or entirely, the portion of the caliper pierced with the 'bore, that or the flange comprises two bores for the passage of two tubes for connection with a workpiece, with a second bending bracket or not, the tubes being or not of the same diameter. Advantageously, the stirrup is made of rigid plastic, bending being possible without breaking the stirrup thanks to lateral jaws (not shown) which keep the stirrup in lateral compression preventing it from crushing due to the bending.

Claims

1. Connection assembly (1) comprising at least one end of rigid cylindrical tube (2) for connection with a part provided with a clean opening to cooperate with the end of said end, a flange

(22, 40, 44, 48, 56) for clamping drilled right through by at least one bore (24) for passing the end of said end piece, means for longitudinal abutment of the tube end piece on the flange, and means (26) for fixing the flange to the part, characterized in that it comprises at least one stirrup (5, 41, 45, 54, 59) in abutment on the flange, forming a roller for bending the bent end of the tube end, with a bending radius R less than or equal to a of the order of 1.2 times the external diameter D of said tube, said tube end being bent m located at its end by bending on said stirrup.

2. Assembly according to claim 1, characterized in that it comprises two bending stirrups respectively forming bending rollers of two tube ends, with bending radii R and R ', each of value less than or equal to order of 1.2 times the respective external diameters D and D 'of said tubes.

3. Assembly according to any one of the preceding claims, characterized in that the bending radius is between 0.8 and 1.1 times the external diameter of the corresponding tube.

4. Assembly according to any one of the preceding claims, characterized in that the end (3) of the tube is bent at 90 °.

5. Assembly according to any one of the preceding claims, characterized in that the flange and the stirrup are mounted free in rotation relative to one another.

6. An assembly according to any one of claims 1 to 4, characterized in that it comprises means (20, 20 ', 31, 32, 33; 42, 43; 46, 47; 49, 51; 57, 58 ) indexing the caliper on the flange in at least two different positions.

7. The assembly of claim 6, characterized in that the indexing means are constituted by toothed rings (42, 43) of complementary shapes, located opposite, respectively integral for one of the periphery of the bore of the flange and for the other of the caliper.

8. Assembly according to claim 6, characterized in that, to constitute the means (20, 20 ', 31, 32, 33) for indexing, the cylindrical bore comprises at least four notches or grooves in the axial direction, distributed angularly regularly on the periphery of the bore, and in that the stirrup has lugs of shape complementary to said notches or grooves, with which they are suitable for fitting together, to block the flange in rotation relative to the stirrup .

9. The assembly as claimed in claim 6, characterized in that, to constitute the indexing means, the flange comprises an end part, pierced with the bore, the peripheral lateral side of which forms a toothed crown (46), and the caliper comprises a portion provided with at least one lug (47) vis-a-vis clean as' insert into one or more notches of said ring gear to block the flange in rotation relative to the caliper when the latter is in abutment on the flange.

10. The assembly of claim 6, characterized in that to constitute the indexing means, one of the elements among the flange and the caliper comprises at least two notches, two lugs and / or two flats and the other element comprises at least one lug, a notch or a flat in shape complementary to those of the opposite element, suitable for cooperating with one of said notches or one of said lugs or flats of said opposite element, for lock the flange in rotation relative to the caliper when the latter is in abutment on the flange.

11. The assembly of claim 6, characterized in that, to form the indexing means, the flange comprises an end portion pierced with the bore, the peripheral lateral side forms a cylindrical wall (49) provided with at least two notches (50, 57) or two lugs, and the bracket comprises a wall directed towards the flange provided with at least one lug (51, 58) or a notch of shape complementary to those of the flange in vis- vis-à-vis, suitable for cooperating with one of said notches or pins to block the flange in rotation relative to the caliper when the latter is in abutment on the flange.

12. Assembly according to any one of the preceding claims, characterized in that the stirrup comprises an upper branch (6) provided with a trough (9) for guiding the tube and an elbow bore with said bending radius, agency for allow the bent end of the tube end to be bent towards the bore of the flange, and perpendicular to the chute, a lower branch (8) for abutment and / or lateral indexing with the flange.

13. The assembly of claim 12, characterized in that the chute has ribs (11) for lateral locking of the tube in said chute.

14. An assembly according to any one of the preceding claims, characterized in that it is provided with sealing means (55) of the junction between the part and the tube fitting.

15. Method of manufacturing a connection assembly between a rigid tube end piece and a part, said assembly comprising a clamping flange pierced right through by at least one passage bore at the end of the tube, and means for locking the tube end on the flange, characterized in that: the end of the rigid tube end is bent at 90 ° with a bending radius less than or equal to a of the order of 1.2 times the external diameter of the tube, in a stirrup serving as a bending roller in abutment on the flange, said stirrup and said flange having been previously introduced on the tube and a flange on the end of the end piece leaving the tube a distal cylindrical part .

16. The method of claim 15, characterized in that the bracket being provided with means of indexing relative to the flange, the end of the tube is placed in the bore of the flange depending on the angular position of flange retained indexing relative to the stirrup, and when the collar of the tube is abutted on the flange, this blocks the tube and its stirrup in said angular indexing position determined relative to the flange.