Sleeve for vehicle air spring and vehicle air spring including same

Abstract

To provide a sleeve for a vehicle air spring which achieves improvement of durability and manufacturing efficiency of the sleeve, and to provide a vehicle air spring including the same.SOLUTION: A sleeve for a vehicle air spring according to one embodiment of the invention includes at least an upper sleeve and a lower sleeve. An upper end circumferential portion of the upper sleeve is coupled to a top mount part, a lower end circumferential portion of the upper sleeve is adhered to an upper end circumferential portion of the lower sleeve. A lower end circumferential portion of the lower sleeve is coupled to a piston portion, and one of the upper sleeve and the lower sleeve may be formed so as to include an area which forms a lobe.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a sleeve for a vehicle air spring and a vehicle air spring including the same, and more particularly to a sleeve for a vehicle air spring and a vehicle air spring including the same, which have improved durability and improved manufacturing efficiency of the sleeve for the vehicle air spring. [Background technology]

[0002] An automobile suspension is a device that exists between the body and the wheels, connecting these two rigid bodies using one or more links. It is supported in the vertical direction by springs and shock absorbers, and in other directions, it performs the function of mechanically harmonizing the relative movement between the body and the wheels by appropriately balancing high rigidity and flexibility.

[0003] Such a suspension must effectively block irregular road inputs that occur while the vehicle is running, providing passengers with a comfortable ride; it must provide driving convenience by appropriately controlling the vehicle body vibrations caused by the driver's driving behavior and curvature of the road; and it must maintain an appropriate level of vertical load on the tire's contact patch when driving on irregular road surfaces, ensuring vehicle maneuverability and stability during cornering, braking, and driving.

[0004] To meet these requirements, various types of suspensions have been developed and applied to vehicles. Recently, air suspensions have been widely adopted in luxury passenger cars, which improve ride comfort by changing the volume of the sleeve that forms the air spring to change the air spring constant, and automatically maintain vehicle height by changing the amount of air.

[0005] Since such sleeves are repeatedly deformed, they require excellent durability, but conventional sleeves have had difficulty meeting this requirement. For example, to improve durability, conventional rubber sleeves have required a complex fiber-reinforced process to reinforce their rigidity, but this has led to a problem of significantly lowering the efficiency of sleeve manufacturing. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] European Patent No. 2,090,801 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made to solve the above-mentioned problems, and aims to provide a sleeve for a vehicle air spring, which has improved durability and improved sleeve manufacturing efficiency, and an air spring for a vehicle including the same.

[0008] The present invention also provides a sleeve for a vehicle air spring, and a vehicle air spring including the same, which can improve product performance by improving design freedom.

[0009] The present invention also provides a sleeve for a vehicle air spring, which allows easy stress management of the material through management of the expansion rate of the sleeve, and an air spring for a vehicle including the same.

[0010] In addition, the present invention provides a sleeve for a vehicle air spring, in which the sleeve is divided into a plurality of pieces and each piece is manufactured by injection molding, thereby improving the flowability of the injection molding during the injection molding of each sleeve and improving the quality of the sleeve, and an air spring for a vehicle including the same. [Means for solving the problem]

[0011] A sleeve 500 for a vehicle air spring according to one embodiment of the present invention includes at least an upper sleeve 520 and a lower sleeve 540, wherein an upper circumferential portion 522 of the upper sleeve 520 is connected to a top mount portion, a lower circumferential portion 524 of the upper sleeve 520 is connected to an upper circumferential portion 542 of the lower sleeve 540, and a lower circumferential portion 544 of the lower sleeve 540 is connected to a piston portion, and one of the upper sleeve 520 and the lower sleeve 540 may be configured to include a region forming a lobe.

[0012] The upper sleeve 520 and the lower sleeve 540 may be made of a thermoplastic material by injection molding.

[0013] For example, the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 may be attached to the upper circumferential portion 542 of the lower sleeve 540 by welding them together.

[0014] According to one embodiment of the present invention, the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 are arranged to overlap each other, and one of the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 may have a step portion 546 formed along the circumferential direction for positioning the remaining sleeve.

[0015] In another embodiment, the lower circumferential portion 524 of the upper sleeve 520 may include a first flange extending outward, and the upper circumferential portion 542 of the lower sleeve 540 may include a second flange extending outward, and the lower circumferential portion 524 of the upper sleeve 520 may be attached to the upper circumferential portion 542 of the lower sleeve 540 by welding the first flange and the second flange.

[0016] Furthermore, the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 are arranged to overlap each other, the sleeve arranged on the inside in the overlapping region includes a laser energy absorbing material, and the sleeve arranged on the outside includes a laser energy transmissive material, and the welding can be laser welding.

[0017] According to one embodiment of the present invention, the sleeve for the vehicle air spring further includes an intermediate sleeve 660 interposed between the upper sleeve 620 and the lower sleeve 640, and the lower circumferential portion 624 of the upper sleeve 620 may be connected to the upper circumferential portion 662 of the intermediate sleeve 660, and the lower circumferential portion 664 of the intermediate sleeve 660 may be connected to the upper circumferential portion 642 of the lower sleeve 640.

[0018] As an example, the lower circumferential portion 624 of the upper sleeve 620 and the upper circumferential portion 662 of the intermediate sleeve 660 may be welded together, thereby attaching the lower circumferential portion 624 of the upper sleeve 620 to the upper circumferential portion 662 of the intermediate sleeve 660, and the lower circumferential portion 664 of the intermediate sleeve 660 may be welded together to the upper circumferential portion 642 of the lower sleeve 640, thereby attaching the lower circumferential portion 664 of the intermediate sleeve 660 to the upper circumferential portion 642 of the lower sleeve 640.

[0019] In addition, the lower circumferential portion 624 of the upper sleeve 620 and the upper circumferential portion 662 of the intermediate sleeve 660 are arranged to overlap each other, and one of the upper circumferential portion 662 of the intermediate sleeve 660 and the lower circumferential portion 624 of the upper sleeve 620 may have a step portion 666 for positioning formed along the circumferential direction, and the lower circumferential portion 664 of the intermediate sleeve 660 and the upper circumferential portion 642 of the lower sleeve 640 are arranged to overlap each other, and one of the lower circumferential portion 664 of the intermediate sleeve 660 and the upper circumferential portion 642 of the lower sleeve 640 may have a step portion 668 for positioning formed along the circumferential direction.

[0020] Furthermore, the lower circumferential portion 624 of the upper sleeve 620 and the upper circumferential portion 662 of the intermediate sleeve 660 are arranged to overlap each other, the lower circumferential portion 664 of the intermediate sleeve 660 and the upper circumferential portion 642 of the lower sleeve 640 are arranged to overlap each other, the sleeve arranged inside in the overlapping region includes a laser energy absorbing material, and the sleeve arranged outside includes a laser energy transmissive material, and the welding can be laser welding.

[0021] As another example, the lower circumferential portion 624 of the upper sleeve 620 may include a third flange extending outward, the upper circumferential portion 662 of the intermediate sleeve 660 may include a fourth flange extending outward, and the third flange and the fourth flange may be welded together to attach the lower circumferential portion 624 of the upper sleeve 620 to the upper circumferential portion 662 of the intermediate sleeve 660, the lower circumferential portion 664 of the intermediate sleeve 660 may include a fifth flange extending outward, and the upper circumferential portion 642 of the lower sleeve 640 may include a sixth flange extending outward, and the fifth flange and the sixth flange may be welded together to attach the lower circumferential portion 664 of the intermediate sleeve 660 to the upper circumferential portion 642 of the lower sleeve 640. [Effects of the Invention]

[0022] According to one embodiment of the present invention, the sleeve is divided into multiple pieces and each piece is injection molded independently, which improves durability and improves sleeve manufacturing efficiency. In addition, improved design flexibility improves product performance, and material stress can be easily managed by controlling the sleeve's expansion rate.

[0023] Furthermore, according to one embodiment of the present invention, the sleeve is divided into a plurality of pieces, each of which is manufactured by injection molding, thereby improving the flowability of the injection molding during the injection molding of each sleeve, thereby improving the quality of the sleeve. [Brief explanation of the drawings]

[0024] [Figure 1]1 is a perspective view of a sleeve according to an embodiment of the present invention. [Figure 2] FIG. 2 is an exploded perspective view of the sleeve shown in FIG. 1. [Figure 3] FIG. 2 is a cross-sectional view of the sleeve shown in FIG. [Figure 4] FIG. 10 is a perspective view of a sleeve according to yet another embodiment of the present invention. [Figure 5] FIG. 5 is an exploded perspective view of the sleeve shown in FIG. 4. [Figure 6] FIG. 5 is a cross-sectional view of the sleeve shown in FIG. 4. DETAILED DESCRIPTION OF THE INVENTION

[0025] The present invention may be modified in various ways and may have various embodiments. A specific embodiment will be described in detail with reference to the drawings. However, this is not intended to limit the present invention to the specific embodiment, and all modifications, equivalents, and alternatives within the spirit and technical scope of the present invention are to be understood. In describing the various drawings, like reference numerals are used to refer to like elements. Terms such as first, second, A, and B may be used to describe various elements, but these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element may be referred to as a second element, and similarly, the second element may be referred to as the first element, without departing from the scope of the present invention. The term "and / or" includes a combination of multiple related listed items or any of multiple related listed items. When a component is referred to as being "coupled" or "connected" to another component, it should be understood that the component may be directly coupled or connected to the other component, but that there may be other intermediate components. On the other hand, when a component is described as being "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between. The terms used in this application are merely used to describe particular embodiments and are not intended to limit the present invention. The singular includes the plural unless the context clearly dictates otherwise. In this application, the terms "comprise" or "have" are intended to specify the presence of a specified feature, number, step, operation, component, part, or combination thereof, but should be understood not to preclude the presence or addition of one or more other features, number, step, operation, component, part, or combination thereof. Furthermore, the terms "first" and "second" are used herein for distinction purposes only and should not be understood to indicate or infer any order or priority.Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this invention belongs. Terms defined in commonly used dictionaries should be interpreted to have a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted in an ideal or overly formal sense unless expressly defined in this application. In addition, the term "about" should be understood herein to include the range of manufacturing tolerances in the art to which this invention belongs.

[0026]

[0023] In the entire specification and claims, when a part includes a certain element, this does not mean that it excludes other elements but that it may further include other elements unless otherwise specified.

[0024] Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0027] The air spring may be disposed between the top mount portion and the piston portion and may include a housing and a sleeve.

[0028] According to one embodiment of the present invention, the sleeve may be hermetically fixed at one end to the top mount portion and at the other end to the piston portion. The sleeve may be enclosed by a housing.

[0029] For example, the sleeve is an air bag whose volume changes as the piston moves up and down. That is, the sleeve, which has a certain internal pressure, changes its volume as the piston moves up and down, and the internal pressure changes accordingly, acting as a spring.

[0030] According to one embodiment of the present invention, one end of the sleeve may be airtightly fixed to the top mount portion and the other end may be airtightly fixed to the inner surface of the piston portion. The sleeve may be surrounded by a housing. When the piston portion moves upward in the axial direction relative to the sleeve, the bent portion of the sleeve, i.e., the portion where the rolling lobe is formed, may be rolled up together with the piston portion to form a ball. As a result, the air inside the sleeve is compressed, causing the air spring to operate as a spring.

[0031] Fig. 1 is a perspective view of a sleeve according to an embodiment of the present invention. The sleeve shown in Fig. 1 is attached to a top mount portion and a piston portion and has not yet been formed with lobes. Fig. 2 is an exploded perspective view of the sleeve shown in Fig. 1. Fig. 3 is a cross-sectional view of the sleeve shown in Fig. 1.

[0032] 1 to 3, a sleeve 500 for a vehicle air spring according to an embodiment of the present invention may be, for example, generally cylindrical and may include at least an upper sleeve 520 and a lower sleeve 540. An upper circumferential portion 522 of the upper sleeve 520 may be coupled to a top mount portion, and a lower circumferential portion 524 of the upper sleeve 520 may be coupled to an upper circumferential portion 542 of the lower sleeve 540. A lower circumferential portion 544 of the lower sleeve 540 is coupled to a piston portion.

[0033] In FIG. 1, of the upper sleeve 520 and the lower sleeve 540, the lower sleeve 540 is configured to include a region that forms a rolling lobe, but the upper sleeve 520 may be configured to include a region that forms a rolling lobe.

[0034] In the present invention, the sleeve 500 can be manufactured separately into a sleeve including a region forming a rolling lobe and a sleeve not including such a region, thereby improving the design freedom of the sleeve 500 and the manufacturing efficiency of the sleeve while still satisfying the high rigidity required of the sleeve 500.

[0035] For example, the upper sleeve 520 and the lower sleeve 540 may be made of the same material, but the sleeve that does not include the area that forms the rolling lobe may be made of a material that is stiffer than the rest of the sleeve, because a stiffer material may not be suitable for forming the rolling lobe.

[0036] Additionally, the upper sleeve 520 and the lower sleeve 540 may be manufactured by injection molding using a thermoplastic elastomer (TPE) material.

[0037] Thermoplastic elastomer materials can be molded by injection molding, extrusion blow molding, etc., like general plastic materials, and are reusable, but they retain the properties of elastomers.

[0038] According to one embodiment of the present invention, the upper sleeve 520 and the lower sleeve 540 are independently manufactured by injection molding using a thermoplastic elastomer material, which improves the design flexibility of the upper sleeve 520 and the lower sleeve 540. For example, the sleeve including the region where the rolling lobe is formed can be designed to have excellent rigidity and spring characteristics by varying the thickness in the longitudinal direction.

[0039] Furthermore, the flowability of the sleeve 500 during injection molding can be improved. The sleeve 500 according to one embodiment of the present invention can be designed to have different inner diameters in the longitudinal direction, but this can cause poor flowability during injection molding when a single sleeve is injection molded, making quality control of the sleeve difficult. In the present invention, the sleeve 500 is manufactured separately into the upper sleeve 520 and the lower sleeve 540, which can improve the flowability during injection molding.

[0040] According to one embodiment of the present invention, the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 may be attached to the upper circumferential portion 542 of the lower sleeve 540 by welding them together.

[0041] For example, the lower circumferential portion 524 of the upper sleeve 520 can be attached to the upper circumferential portion 542 of the lower sleeve 540 by positioning the upper sleeve 520 and the lower sleeve 540 (butt joint) so that the ends of the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 face each other and welding the opposing portions.

[0042] More preferably, according to one embodiment of the present invention, the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 may be disposed to overlap each other, as shown in Figure 3. The overlapping region may be welded to attach the lower circumferential portion 524 of the upper sleeve 520 to the upper circumferential portion 542 of the lower sleeve 540.

[0043] For this welding, a step portion for positioning the remaining sleeve may be formed along the circumferential direction on one of the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540. As an example, FIG. 3 shows a step portion 546 formed along the circumferential direction on the lower circumferential portion 524 of the upper sleeve 520.

[0044] According to one embodiment of the present invention, the upper sleeve 520 and the lower sleeve 540 may be joined at the overlapping region by laser welding. That is, the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 may be joined by laser welding along the circumferential direction. For this purpose, as an example, the inner sleeve may include a laser energy absorbing material, and the outer sleeve may include a laser transmissive material. As an example of a laser energy absorbing material, the inner sleeve may include carbon black.

[0045] Additionally, according to one embodiment of the present invention, each of the lower circumferential portion 524 of the upper sleeve 520 and the upper circumferential portion 542 of the lower sleeve 540 may be configured to include an outwardly extending flange.

[0046] The flanges may be positioned in opposing contact with one another and welded together to attach the lower circumferential end portion 524 of the upper sleeve 520 to the upper circumferential end portion 542 of the lower sleeve 540 .

[0047] Fig. 4 is a perspective view of a sleeve according to yet another embodiment of the present invention, Fig. 5 is an exploded perspective view of the sleeve shown in Fig. 4, and Fig. 6 is a cross-sectional view of the sleeve shown in Fig. 4.

[0048] 4 to 6, the sleeve 600 according to an embodiment of the present invention may further include an intermediate sleeve 660 interposed between the upper sleeve 620 and the lower sleeve 640. A lower circumferential portion 624 of the upper sleeve 620 may be coupled to an upper circumferential portion 662 of the intermediate sleeve 660, and a lower circumferential portion 664 of the intermediate sleeve 660 may be coupled to an upper circumferential portion 642 of the lower sleeve 640. A lower circumferential portion 644 of the lower sleeve 640 may be coupled to the piston portion. An upper circumferential portion 622 of the upper sleeve 620 may be coupled to the top mount portion.

[0049] As an example, the lower circumferential portion 624 of the upper sleeve 620 and the upper circumferential portion 662 of the intermediate sleeve 660 may be welded together to attach the lower circumferential portion 624 of the upper sleeve 620 to the upper circumferential portion 662 of the intermediate sleeve 660, and the lower circumferential portion 664 of the intermediate sleeve 660 may be welded together to attach the lower circumferential portion 664 of the intermediate sleeve 660 to the upper circumferential portion 642 of the lower sleeve 640.

[0050] For example, the lower circumferential portion 624 of the upper sleeve 620 can be attached to the upper circumferential portion 662 of the intermediate sleeve 660 by positioning the upper sleeve 620 and the intermediate sleeve 660 so that the ends of the lower circumferential portion 624 of the upper sleeve 620 and the upper circumferential portion 662 of the intermediate sleeve 660 face each other and welding the opposing portions.

[0051] As a result, the design freedom of the sleeve 600 of the present invention can be further improved. For example, the upper sleeve 620 and the lower sleeve 640 can be independently made of different materials, but in a structure in which the upper sleeve 620 and the lower sleeve 640 are joined together, the freedom in material selection can be reduced due to the joining. On the other hand, when the intermediate sleeve 660 is interposed between the upper sleeve 620 and the lower sleeve 640, even if materials that are difficult to join are selected for the upper sleeve 620 and the lower sleeve 640, the difficulty of joining can be resolved through the intermediate sleeve 660.

[0052] More preferably, according to one embodiment of the present invention, as shown in Figure 6, the lower circumferential portion 624 of the upper sleeve 620 and the upper circumferential portion 662 of the middle sleeve 660 may be arranged to overlap each other, and the lower circumferential portion 664 of the middle sleeve 660 and the upper circumferential portion 642 of the lower sleeve 640 may be arranged to overlap each other. In this case, a step portion 666 for positioning may be formed along the circumferential direction on one of the upper circumferential portion 662 of the middle sleeve 660 and the lower circumferential portion 624 of the upper sleeve 620, and a step portion 668 for positioning may be formed along the circumferential direction on one of the lower circumferential portion 664 of the middle sleeve 660 and the upper circumferential portion 642 of the lower sleeve 640. Figure 6 shows, as an example, the step portions 666, 668 formed on the upper circumferential portion 662 of the middle sleeve 660 and the lower circumferential portion 664 of the middle sleeve 660.

[0053] The lower circumferential portion 624 of the upper sleeve 620 and the upper circumferential portion 662 of the middle sleeve 660 are arranged to overlap each other, and the overlapping region is welded, thereby attaching the lower circumferential portion 624 of the upper sleeve 620 to the upper circumferential portion 662 of the middle sleeve 660. Similarly, the lower circumferential portion 664 of the middle sleeve 660 and the upper circumferential portion 642 of the lower sleeve 640 are arranged to overlap each other, and the overlapping region is welded, thereby attaching the lower circumferential portion 664 of the middle sleeve 660 to the upper circumferential portion 642 of the lower sleeve 640. In FIG. 6, as an example, the middle sleeve 660 is arranged on the inside of the overlapping region, and the upper sleeve 620 to the lower sleeve 640 are arranged on the outside. In such an arrangement, when the middle sleeve 660 and the upper sleeve 620 or the lower sleeve 640 are laser welded together, the middle sleeve 660 can be made of a laser energy absorbing material (e.g., carbon black), and the upper sleeve 620 and the lower sleeve 640 can be made of a laser-transparent material.

[0054] Additionally, according to one embodiment of the present invention, the lower circumferential end portion 624 of the upper sleeve 620 and the upper circumferential end portion 662 of the middle sleeve 660 may each be configured to include an outwardly extending flange. The flanges may be positioned to face each other in contact with each other, and the lower circumferential end portion 624 of the upper sleeve 620 may be attached to the upper circumferential end portion 662 of the middle sleeve 660 by welding the flanges.

[0055] Similarly, the lower circumferential end portion 664 of the intermediate sleeve 660 and the upper circumferential end portion 642 of the lower sleeve 640 may each be configured to include an outwardly extending flange. The flanges may be positioned in opposing contact with each other and welded to attach the lower circumferential end portion 664 of the intermediate sleeve 660 to the upper circumferential end portion 642 of the lower sleeve 640. [Explanation of symbols]

[0056] 500, 600: Sleeve 520: Upper sleeve 540: Lower sleeve 660: Intermediate sleeve

Claims

1. A sleeve (500) for a vehicle air spring, The sleeve includes at least an upper sleeve (520) and a lower sleeve (540); An upper circumferential portion (522) of the upper sleeve (520) is connected to a top mount portion, and a lower circumferential portion (524) of the upper sleeve (520) is connected to an upper circumferential portion (542) of the lower sleeve (540), The lower end circumferential portion (544) of the lower sleeve (540) is connected to the piston portion, one of the upper sleeve (520) and the lower sleeve (540) is configured to include a region forming a lobe; the lower end circumferential portion (524) of the upper sleeve (520) and the upper end circumferential portion (542) of the lower sleeve (540) are arranged to overlap each other; A sleeve for a vehicle air spring, wherein the outer surface of the lower end circumferential portion (524) of the upper sleeve (520) or the outer surface of the upper end circumferential portion (542) of the lower sleeve (540) is lower radially inward compared to the outer surface of the remaining portion of the upper sleeve (520) or the outer surface of the remaining portion of the lower sleeve (540), so that a step-shaped portion (546) for positioning the remaining sleeve is formed along the circumferential direction.

2. 2. The sleeve for a vehicle air spring according to claim 1, wherein said upper sleeve (520) and said lower sleeve (540) are made by injection molding from a thermoplastic material.

3. 2. A sleeve for a vehicle air spring as set forth in claim 1, wherein the lower end circumferential portion (524) of the upper sleeve (520) and the upper end circumferential portion (542) of the lower sleeve (540) are attached to the upper end circumferential portion (542) of the lower sleeve (540) by welding them together.

4. the lower end circumferential portion (524) of the upper sleeve (520) and the upper end circumferential portion (542) of the lower sleeve (540) each include an outwardly extending flange; 4. The sleeve for a vehicle air spring of claim 3, wherein the flanges are welded to attach the lower circumferential end portion (524) of the upper sleeve (520) to the upper circumferential end portion (542) of the lower sleeve (540).

5. a sleeve disposed inside the overlapping region comprising a laser energy absorbing material; the outer sleeve includes a laser energy transparent material; 4. The sleeve for a vehicle air spring according to claim 3, wherein said welding is a laser welding.

6. A sleeve (500) for a vehicle air spring, The sleeve includes at least an upper sleeve (520) and a lower sleeve (540); An upper circumferential portion (522) of the upper sleeve (520) is connected to a top mount portion, and a lower circumferential portion (524) of the upper sleeve (520) is connected to an upper circumferential portion (542) of the lower sleeve (540), The lower end circumferential portion (544) of the lower sleeve (540) is connected to the piston portion, one of the upper sleeve (520) and the lower sleeve (540) is configured to include a region forming a lobe; The device further includes an intermediate sleeve (660) interposed between the upper sleeve (620) and the lower sleeve (640), The lower end circumferential portion (624) of the upper sleeve (620) and the upper end circumferential portion (662) of the intermediate sleeve (660) are arranged to overlap each other, The outer surface of the lower end circumferential portion (624) of the upper sleeve (620) or the outer surface of the upper end circumferential portion (662) of the intermediate sleeve (660) is lower radially inward than the outer surface of the remaining portion of the upper sleeve (620) or the outer surface of the remaining portion of the intermediate sleeve (660), thereby forming a step portion (666) in a circumferential direction for positioning the remaining sleeve, The lower end circumferential portion (664) of the intermediate sleeve (660) and the upper end circumferential portion (642) of the lower sleeve (640) are arranged to overlap each other, A sleeve for a vehicle air spring, wherein the outer surface of the lower end circumferential portion (664) of the intermediate sleeve (660) or the outer surface of the upper end circumferential portion (642) of the lower sleeve (640) is lower radially inward compared to the outer surface of the remaining portion of the intermediate sleeve (660) or the outer surface of the remaining portion of the lower sleeve (640), so that a step-shaped portion (668) for positioning the remaining sleeve is formed along the circumferential direction.

7. 7. A sleeve for a vehicle air spring as set forth in claim 6, wherein the lower end circumferential portion (624) of the upper sleeve (620) is connected to the upper end circumferential portion (662) of the intermediate sleeve (660), and the lower end circumferential portion (664) of the intermediate sleeve (660) is connected to the upper end circumferential portion (642) of the lower sleeve (640).

8. The lower circumferential portion (624) of the upper sleeve (620) and the upper circumferential portion (662) of the intermediate sleeve (660) are welded together, thereby attaching the lower circumferential portion (624) of the upper sleeve (620) to the upper circumferential portion (662) of the intermediate sleeve (660); 7. A sleeve for a vehicle air spring as set forth in claim 6, wherein the lower end circumferential portion (664) of the intermediate sleeve (660) and the upper end circumferential portion (642) of the lower sleeve (640) are attached to each other by welding the lower end circumferential portion (664) of the intermediate sleeve (660) to the upper end circumferential portion (642) of the lower sleeve (640).

9. a sleeve disposed inside the overlapping region comprising a laser energy absorbing material; the outer sleeve includes a laser energy transparent material; 9. The sleeve for a vehicle air spring as set forth in claim 8, wherein said welding is a laser welding.

10. the lower end circumferential portion (624) of the upper sleeve (620) and the upper end circumferential portion (662) of the intermediate sleeve (660) each include an outwardly extending flange; the lower end circumferential portion (624) of the upper sleeve (620) and the upper end circumferential portion (662) of the intermediate sleeve (660) are attached to the upper end circumferential portion (662) of the intermediate sleeve (660) by welding flanges of the lower end circumferential portion (624) of the upper sleeve (620) and the upper end circumferential portion (662) of the intermediate sleeve (660); the lower end circumferential portion (664) of the intermediate sleeve (660) and the upper end circumferential portion (642) of the lower sleeve (640) each include an outwardly extending flange; 7. A sleeve for a vehicle air spring as set forth in claim 6, wherein flanges of the lower end circumferential portion (664) of the intermediate sleeve (660) and the upper end circumferential portion (642) of the lower sleeve (640) are welded together, thereby attaching the lower end circumferential portion (664) of the intermediate sleeve (660) to the upper end circumferential portion (642) of the lower sleeve (640).

11. 2. A sleeve for a vehicle air spring as claimed in claim 1, wherein the sleeve not including the area forming the lobes is made of a stronger material than the remainder of the sleeve.

12. 2. The sleeve for a vehicle air spring according to claim 1, wherein the sleeve including the region forming the lobe includes a section of varying thickness along its length.

13. 10. The sleeve for a vehicle air spring according to claim 5 or claim 9, wherein the sleeve disposed inside the overlapping region contains carbon black.

14. A sleeve (500, 600) for a vehicle air spring according to any one of claims 1 to 12; a top mount portion to which the upper end circumferential portion (522, 622) of the upper sleeve (520, 620) is attached; An air spring for a vehicle, comprising a piston portion to which the lower end circumferential portion (544, 644) of the lower sleeve (540, 640) is attached.

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