FR2853043A1 - Hose for vehicles air conditioning system, has swivel joint providing connection between rigid and flexible parts, and satisfying rotation function, sealing function, and locking or axial hold function between parts - Google Patents

Abstract

The hose has a rigid part (1) with a metallic tubular component, and a flexible part (3) with an undulating metal. A swivel joint (15) providing watertight connection between the parts satisfies a rotation function, a sealing function, and a locking or axial hold function between the parts. The joint is positioned or mounted between two rigid metallic tubular ferrules (15a, 15b).

Description

FLEXIBLE, PARTICULARLY FOR A VEHICLE AIR CONDITIONING SYSTEM A

ENGINE

  The invention relates to a hose, in particular for a motor vehicle air conditioning system.

  In the automotive industry, for example, the current trend is to equip motor vehicles with an air conditioning system. In general, an air conditioning system comprises in particular a compressor carried by the engine block which is subjected to vibrations, and an evaporator carried by the chassis of the vehicle which is stationary. These two elements of the air conditioning system are therefore connected to each other by a hose which comprises rigid parts and flexible parts, knowing, moreover, that these two elements are not grouped in the same location under the engine hood. , 15 the evaporator being situated on the side of the passenger compartment of the vehicle into which it is to supply air conditioning.

  A conventional hose comprises rigid parts in the form of metal tubes, made of aluminum for example, and flexible tubular parts of multilayer structure with at least one internal layer of rubber or polymer forming a fluid-tight and sound-resistant barrier. chemical aggressiveness, an intermediate reinforcement structure in the form of a textile or metallic braid or web, and an external protective envelope. Generally, the refrigerant used is freon under a pressure of the order of 20 to 40 bars.

  However, at present, we wish to replace freon with C02 for essentially ecological reasons. However, the CO 2 is at a temperature of the order of 1600 and at a working pressure of the order of 150 bars, which implies the use of a hose no longer comprising flexible rubber-based parts. which does not support the conditions of use of CO2. In other words, the hose comprises at least one metal part over its entire length, both in its rigid parts and its flexible parts, and the ends of a rigid part and of a flexible part of the hose are connected one to the other. the other by welding, such a connection notably lacking in torsional flexibility.

  An object of the invention is therefore to solve in particular this problem of lack of torsional flexibility at the connection zones between a flexible part and a rigid part of the hose and at the connection zones at each end of the hose.

  To this end, the invention provides a hose for the air conditioning system of a motor vehicle, which is characterized in that it comprises at least one metal part over its entire length and means 10 to give it flexibility in torsion.

  According to a first embodiment of the invention, the means imparting torsion to the hose comprise at least one rotary connector which is tightly connected between two parts of the hose or between one end of the hose and one end of a rigid element of the air conditioning system 15, the connector ensuring at least three functions: a rotation function, a sealing function and a locking or axial holding function.

  According to another exemplary embodiment of the invention, the means imparting torsion to the hose are obtained by configuring at least part of the hose in a particular shape without it being necessary to provide a swivel connector ensuring the three aforementioned functions .

  Other advantages, characteristics and details of the invention will emerge from the additional description which follows with reference to the appended drawings, given solely by way of example and in which: FIG. 1 is a view in axial section of the ends of parts rigid and flexible hose comprising at least one metal part over its entire length with means for imparting torsional flexibility in the form of a swivel joint; FIGS. 2 to 23 are half-views or views in axial section of other embodiments of rotary couplings; and - Figures 24 to 26 are partial schematic perspective views of a hose comprising at least one metal part over its entire length with means to give it flexibility in torsion other than a swivel joint.

  Referring to FIG. 1, the ends of a rigid part 1 and of a semi-rigid part 3 of an air conditioning hose comprising at least one metal part over its entire length are to be connected in leaktight manner, and conveying a refrigerant which can be CO2 for example.

  The rigid part 1 consists of a metallic tubular element 5, while the flexible part 3 comprises at least one metallic corrugator 7 for example which does not have sufficient torsional flexibility.

  According to one embodiment, the sealed connection between the ends of the rigid 1 and flexible 3 parts is provided by a rotary connector 15 which must fulfill at least three functions, namely: a rotation function between the two ends, a sealing function and a locking or axial holding function between the two ends. The rotary union 15 15 is positioned or mounted between two rigid metallic tubular end pieces 15a and 15b, coaxial and axially aligned with each other which are respectively connected to the ends of the rigid 1 and flexible parts 3. More precisely, the ends of the two end pieces 15a and 15b terminate in two radially external edges 102a and 102b, folded at 900 for example, and located at a distance from each other. An annular element 100 at least partially made of an elastomeric material is mounted between and around the two flanges 102a and 102b to ensure the function of rotation in shear and / or in torsion, and the sealing function. To ensure the axial retention between the two end pieces 1 5a and 15b, an annular cover 105 is reported with a L-shaped half-cross section 25 which is then folded back to give it a U-shaped half section which traps the item 100.

  Advantageously, to limit the pressure drops in the hose, the flange 102a of the end piece 15a can be produced in the form of a bulb 107 by deforming the end of the end piece 15a, so that 30 l free end 109 of the end piece 15a comes substantially into contact with the base of the rim 102b of the end piece 15b. In this embodiment, the annular element 100 which also performs the sealing function is externalized, that is to say that its temperature is closer to that of the engine environment 4 2853043 than that of the refrigerant. , which represents a significant advantage.

  According to another embodiment illustrated in FIG. 2, the rotary connector 15 also consists of an annular element 110 at least partially made of an elastomeric material and which performs both the function of rotation in shear and / or in torsion and the sealing function.

  More specifically, the end piece 15b is a male end piece whose free end is flared outward to form a rim 112 around which the annular element 110 is molded or adhered to at least one surface. The end piece 10 15a is a female end piece whose free end is widened to cover the annular element 110 and end with a radially internal flange 114 which traps the annular element 110. The axial strength of the two end pieces 15a and 15b (end effect ) is provided by the two flanges 112 and 114 which can compress the annular element 110.

  According to another embodiment illustrated in FIG. 3, the rotary connector 15 consists of an annular element 118 at least partially made of an elastomeric material which provides the three functions of rotation in shear and / or in torsion, sealing and axial hold.

  The end piece 15b is a male end piece which is engaged in the end piece 15a which forms a female end piece, and the annular element 118 is molded or adhered between the male end piece 15b and the female end piece 15a on the one hand, and around the female end piece 15a on the other hand.

  According to another embodiment illustrated in FIG. 4, the rotary connector 15 is constituted by an annular element 120 at least partially made of an elastomeric material which is crimped and / or bonded between the two male ends 15b and female 15a which are engage one in the other.

  The annular element 120 works in shear and / or in torsion to ensure the rotation function and also ensures the sealing function. The axial strength between the two end pieces 15a and 15b is obtained by a boss 122 provided for example towards the free end of the end piece 15b and by a boss 124 of complementary shape provided in the female end piece 15a.

  According to another embodiment illustrated in FIG. 5, the rotary connector 15 consists of an annular element 130 at least partially made of an elastomeric material which is trapped or pinched between the male ends 15b and female 15a which engage one in the other. The annular element 130 ensures a rotational movement by shearing and sliding.

  To this end, the annular element 130 is of elongated shape with a part 130a 5 folded outwards and which comes into contact with the female end piece 15a. The axial holding between the two end pieces 15a and 15b is ensured by a boss 132 for example provided towards the free end of the male end piece 15b and by a radially internal flange 134 provided at the free end of the female end piece 15a, these two flanges 132 and 134 being located on either side of the annular element 130.

  According to another embodiment illustrated in FIG. 6, the rotary connector 15 comprises an annular element 140 at least partially made of an elastomeric material which is fixed between two radially external flanges 142 and 144 of the two female ends 15b and male 15a. The annular element 140 provides the function of rotation by shearing and / or torsion and the sealing function, while the axial retention is provided by the two flanges 142 and 144 of the two end pieces 15a and 15b which compress the element 140. The annular element 140 can be laminated with rigid metallic or composite parts for example.

  According to another embodiment illustrated in Figure 7, the components of the rotary connector 15 are mounted with a compression preload. More specifically, the end piece 15b which forms a male end piece ends in a radially outer rim 150, substantially folded back at 90, and the end piece 15a forms a female end piece whose free end is widened by delimiting an intermediate shoulder 152 situated opposite the flange 150 of the male end piece 15b. An annular sealing element 155 at least partially made of an elastomeric material, for example laminated, is adhered by molding for example between the flange 150 and the shoulder 152. This annular element 155 ensures the function of rotation in shear and / or 30 torsion and sealing function, but to prevent it from working in tension under the pressure of the fluid conveyed by the hose, it is mounted in compression preload. To this end, another annular element 157 of a laminated elastomeric material for example is mounted on the other side of the flange 150 of the male end piece 150 by bearing on a flange 159 provided at the free end of the female end piece 15a. This other annular element 157 is put in compression preload which is transmitted to the annular element 155, and also works in shear and / or in torsion during the rotation of the rotary connector 15. The axial strength of the two end pieces 15a and 15b is provided by the shoulder with 152 and the flange 159.

  According to another embodiment illustrated in FIG. 8, which is a variant of that of FIG. 7, the annular element 157 is constituted by an O-ring 160 made of an elastomeric material for example.

  According to another embodiment illustrated in FIGS. 9 and 10, the rotary connector 15 is constituted by an annular element 170 at least partially made of an elastomeric material mounted in compression preload between the two radially external edges 172 and 174 provided at the opposite ends one of the other of the two end pieces 15a and 15b. The annular element 170 may be a laminated element which is placed in compression preload by means 175 capable of working in torsion and of taking up tensile forces for axial retention.

  In the case of Figure 9, the means 175 are constituted by a cable 176 mounted inside the end pieces 15a and 15b. This cable 176 is fixed 20 to two perforated cups 177 whose peripheral edges come to bear on two shoulders 178 formed in the end pieces 15a and 15b.

  In the case of FIG. 10, the means 175 consist of several cables 176 mounted outside of the two end pieces 15a and 15b, the ends of the cables 176 being fixed to two stops 182 respectively integral with the two end pieces 15a and 15b.

  According to another embodiment illustrated in FIG. 11, the rotary connector 15 comprises a sliding ring 180 mounted between the end pieces 15a and 15b to allow the rotary movement of the rotary connector 15. The ring 180 can be made of ceramic, metal or a polymeric material for example. More specifically, the end piece 15b which forms a male end piece has an extra thickness 182 delimiting a flared annular shoulder 184 on which the annular ring 180 is adhered. The female end piece 15a has an enlarged end portion 185 which delimits a shoulder 7 2853043 annular 186 against which the free end face of the male end piece 15b abuts with interposition for example of an elastic buffer zone 188. The enlarged end part 185 has at its free end a radially internal flange 189 which comes in contact with the sliding ring 180. 5 Two annular seals 192 and 194 for example are interposed between the end pieces 15a and 15b to ensure the sealing function. The axial holding between the end pieces 15a and 15b is ensured by the shoulder 186 and the flange 189.

  According to the embodiment illustrated in FIG. 12, which is a variant of that of FIG. 11, the excess thickness 182 of the male endpiece 15b is replaced by a bulb 190 whose tip is covered with an annular bearing 192, in PTFE for example, which forms a sliding ring ensuring the rotation function.

  According to the embodiment illustrated in FIG. 13, which is a variant of that of FIG. 12, the bulb 190 and the annular bearing surface 192 which form the rotary connector 15 are replaced by a sliding ring mounted between two bulbs 197 of the male connector 15b.

  According to another embodiment illustrated in FIG. 14, the rotary connector 15 is constituted by a deep-drawn ball joint 200. More specifically, the end-piece 15b which forms a male end-piece has at its free end a flared shape towards the outside 202 in the form of an arc of a circle, and the end piece 15a which forms a female end piece has a complementary flared shape 204 in an arc of a circle. Between the flared shapes 202 and 204, there is mounted an annular element 206 of arcuate shape and made of an elastomeric material which ensures the functions of rotation and sealing, while the axial resistance between the two end pieces 15a and 15b is ensured by two flared shapes 202 and 204 According to another embodiment illustrated in FIG. 15, which is a variant of that of FIG. 14, the stamped ball joint 200 consists of a torus 210, made of ceramic for example, which is mounted by 30 crimping, overmolding or gluing at the top of a rounded boss 212 projecting from the end piece 15b which forms a male end piece, and which is housed in a cavity of a corrugation 214 present at the end of the end piece 15a which forms a female tip. Two annular seals 216 and 218 are 8 2853043 arranged on either side of the torus 210 between the ends 15b and 15a. The axial holding between the end pieces 15b and 15a is ensured by the corrugation 214 into which the boss 212 enters.

  According to another embodiment illustrated in FIG. 16, the rotary connector 15 consists of balls 220 which are mounted in an annular housing 222 formed between the end pieces 15b and 15a. More specifically, the male endpiece 15b has at its periphery a semicircular recess capable of coming opposite a semi-circular recess of the female endpiece 15a. The balls 220 are introduced into the housing 222 by an opening 224 pierced 10 in the female end piece 15a and closed by a plug 226. The free end face of the male end piece 15b is mounted opposite a shoulder 228 of the female endpiece 15a with the interposition of an elastic buffer zone 230 which is compressed so as to bring the opening 224 and the housing 222 opposite one another to allow the introduction of the balls 220 into the housing 15 222. Two annular seals 232 for example are mounted on either side of the balls 220 between the end pieces 15a and 15b. The rotation of the rotary connector 15 and the axial holding between the end pieces 15a and 15b are ensured by the balls 220 retained in their housing 222.

  According to another embodiment illustrated in FIG. 17, the rotary connector 15 is constituted by a needle bearing 235 mounted between the end pieces 15a and 15b. More specifically, the bearing 235 is engaged by one end of the male end piece 15b until it comes into abutment with a projection such as a bulb 236, and the end of the female end piece 15b is widened so as to delimit a shoulder 237 which keeps the bearing 235 in position and its free end forms a radially internal rim 238 which engages the bulb 236 to ensure the axial retention. The seal is for example ensured by two annular seals 239 mounted between the two end pieces 15a and 15b.

  According to another embodiment illustrated in FIG. 18, the rotary connector 15 comprises at least one annular ring 240 which works in compression and not in shear under the pressure of the fluid conveyed by the hose. More specifically, the ends of the two end pieces 15a and 15b end in two radially external flanges 242 and 244, folded substantially at 90, which face each other and between which are mounted, for example 9 2853043 two seals 246 and 248. A annular cover 250 is attached around the two flanges 242 and 244 to ensure the axial strength between the two end pieces 15a and 15b. The annular cover 250 has a U-shaped half-section with two branches 250a and 250b which partially cover the two flanges 242 and 244 with the interposition of two annular rods 240 to allow the rotation which are mounted between the flange 244 of the end piece 15a and branch 250a, and end piece 15b and branch 250b of cover 250. The rod 240 can be made of metal for example.

  According to the embodiment illustrated in FIG. 19, the rotary connector 15 comprises a ball stop 260 which is mounted between the end pieces 15a and 15b. The end piece 15a forms a male end piece which has a projecting bulb 262 in the direction of its free end, then an increase in diameter which delimits a shoulder 263 and forms a cylindrical seat 264, and finally a radially external rim 266 at its free end . The end piece 15a forms a female end piece with an enlarged end which ends in a radially internal flange 268. The ball stop 260 is mounted around the male end piece 15b between the bulb 262 and the shoulder 264, while the flange 268 of the female end piece 15a is positioned between the bulb 262 and the ball stop 260. An anti-friction ring 270 provides sealing and is mounted between the cylindrical surface 20 264 of the male end piece 15b and the end piece female 15a. The ball stop 260 ensures the rotational movement and the axial holding of the two end pieces 15a and 15b is ensured by the bulb 262 and the shoulder 263 between which the ball stop 260 is mounted.

  According to the embodiment of FIG. 20, the rotary union 25 15 is constituted by a eutectic 280 which has a fluid state at the operating temperature of the hose which is of the order of 1100 to 1500C, and a more rigid state when the hose does not work. More specifically, the end piece 15b which forms a male end piece has an annular peripheral groove 282 forming a housing for receiving the eutectic 280, and the end piece 15a which forms a female end piece has an annular projection such as a bulb 284 on its internal face and which penetrates inside the groove 282 to ensure the axial holding between the two end pieces. Two annular seals 1 o 286 are mounted on either side of the groove 282 between the end pieces 15a and 15b to retain the eutectic in the groove.

  According to the embodiment illustrated in FIG. 21, the end of the flexible part of the hose formed by a metallic corrugator 7 is directly used as a male end piece 5b which is used as a support for carrying ball bearings 290 for example which perform the rotation function and two seals 292 and 294 for example. More precisely, the space between two corrugations is widened if necessary to accommodate the balls 290 there, and the two seals 292 and 294 are placed in two corrugations located towards the free end of the corrugator 7. The connector turning 15 also includes a female end piece 15a located at the end of the rigid part of the flexible and which covers the seals and the balls. The free end of the female end piece 5a is then folded inwards to form a flange 295 which is housed in the hollow of the corrugation which carries the balls 290 to block them axially.

  In the embodiment illustrated in FIG. 22, the rotary connector 15 is constituted by the rotation of a rotary cover 300 with a U-shaped half-straight section with two flanges 302 and 304. The flange 302 is mounted in a groove delimited by two peripheral bulbs 306 of the female end piece 15a, while the rim 304 comes to be mounted in a groove delimited by two peripheral bulbs 308 of the male end piece 15b. The rotation function is provided by the cylindrical surfaces 302a and 304a at the ends of the flanges 302 and 304. The sealing function is provided for example by two O-rings 310 mounted between the female endpiece 15a and 25 the male endpiece 15b, and the axial holding of the rotary connector 15 is ensured by the bulbs 306 and 308 which hold the rotary cover 300 in position.

  Until now, in all the embodiments described, the two rigid 1 and flexible 3 parts of the hose to be connected to each other have been axially aligned with each other.

  According to the embodiment illustrated in FIG. 23, the rotary connector 15 comprises two female ends 15a and male 15b mounted at 900.

  More specifically, the female endpiece 15a has a circular opening 315, and the male endpiece 15b has an end portion 317 of smaller diameter beyond a peripheral shoulder 319. The end portion 317 of the male end piece 15b is engaged in the opening 315 of the female end piece 15a until its shoulder 319 comes into contact with the female end piece 15a, and the end portion of the male end piece 15b which projects at the beyond the opening 315 is retained axially by a circlip 321. The rotation function of the rotary connector is provided by the relative rotation between the female end piece 15a and the male end piece 15b, and the sealing function is provided by two O-rings 323 for example which are mounted between the two cylindrical contact surfaces between the female end piece 15a and the male end piece 15b.

  Until now, the means for giving the hose torsional flexibility to the hose have consisted of a swivel connector forming leaktight connection means between a rigid part and a semi-rigid part of the hose. In the embodiments which will be described below, the torsional flexibility is obtained by configuring at least part of the flexible according to a particular shape.

  According to the embodiment illustrated in FIG. 24, the hose comprises at least one semi-rigid element in the form of a metallic corrugator 7 for example which has two series of inverted corrugations 7a and 7b in a helix, substantially at 450 , which allow a rotational movement, a series of twists undulating, while the other series untwists.

  According to the embodiment illustrated in FIG. 25, a rigid part 7 of the hose has, towards each of its ends, two spiral metal tubes 7a and 7b which are inverted to work in torsion in opposite directions during a rotational movement.

  According to the embodiment of Figure 26, a rigid part 7 of the hose has at least one of its ends a series of capillary metal tubes 7a, each tube being deformable in torsion, and the set of tubes being arranged as follows the shape of a cylinder for example like a lantern or a spring. The set of capillary tubes 7a 30 is connected at each end to a sealed connection box 325.

  In the embodiments of Figures 24 to 26, it is not necessary to provide sealing means and axial locking means.

Claims (17)

  1. Flexible, in particular for the air conditioning system of a motor vehicle, characterized in that it comprises at least one metallic part (1, 3) over its entire length and means (15; 7a; 7b) for give it torsional flexibility.   2. The hose of claim 1, wherein the means for imparting torsion to the hose comprises at least one swivel joint (15) sealingly connected between two parts (1, 3) of the hose or between one end of the hose and a end of a rigid element of the air conditioning system.   3. A hose according to claim 2, in which the rotary connector (15) performs at least three functions between the two ends to which it is connected: a rotation function, a sealing function and a locking or axial holding function. .   4. A hose according to claim 3, in which the function of rotation of the rotary connector (15) is ensured by an annular element (100; 110; 118; 120; 130; 140; 155; 170) at least partially made of an elastomeric material. working in shear and / or in torsion.   5. Hose according to claim 4, wherein the annular element (1 00; 1 1 0; 1 1 8; 120; 130; 140; 155; 170) also performs the sealing function.   6. Flexible according to one of claims 4 or 5, wherein the annular element (140; 155; 170) is a laminated element with rigid metallic or composite parts for example.   7. Flexible according to one of claims 4 to 6, wherein the annular element (140; 155; 170) is mounted with a prestress in compression to avoid working in traction under the action of the fluid carried by the flexible.   8. Flexible according to claim 3, wherein the rotation of the rotary connector (15) is provided by an annular element (180) formed by a sliding ring made of ceramic, metal or a polymeric material for example.   9. Flexible according to claim 3, wherein the rotation function of the rotary connector (15) is provided by balls (220), or by a needle or ball bearing (235, 260).   10. The hose as claimed in claim 3, in which the function of rotation of the rotary connector (15) is provided by the annular surfaces (302a, 304a) of a rotary cover (300).   11. A hose according to claim 3, in which the function of rotation of the rotary connector (15) is ensured by an eutectic (280).   12. Flexible according to one of claims 3 to 8, wherein the annular element ensuring the rotation function of the rotary connector (15) is mounted by overmolding, crimping or pinching between two male ends (15b) and female (15a) respectively secured to the flexible (3) and rigid (1) parts of the flexible.   13. Hose according to one of claims 3 to 8, in which the axial locking function of the rotary connector (15) is ensured by two flanges of the male (15b) and female (15a) end pieces, which compress the annular element ensuring the rotation function of the swivel joint.   14. Hose according to one of claims 3 to 8, wherein the axial locking function of the rotary connector is provided by a rigid element (176) mounted between the male ends (15b) and female (I5a).   15. Hose according to claim 1, wherein the means for imparting torsional flexibility to at least one flexible element of the flexible, such as a metallic corrugator (7), consist of two series of inverted helical undulations (7a , 7b), substantially at 450, which allow a rotational movement, a series of undulations twisting while the other untwists.   16. The hose as claimed in claim 1, in which the means 30 for imparting torsional flexibility to at least one rigid element (7) of the hose consist of at least two metal tubes (7a, 7b) spiraled in opposite directions. one of the other mounted at both ends of the rigid element.   17. Hose according to claim 1, in which the means for imparting torsional flexibility to at least one rigid element (7) of the flexible element consist of at least one series of metallic capillary tubes (7a) deformable in torsion and arranged like a lantern or a spring at at least one end of the rigid element.