A partially multi-layered single-layer sleeve air spring and a manufacturing method thereof

Abstract

The application discloses a local multi-layer single-layer sleeve cylinder type air spring and a manufacturing method, wherein an outer layer rubber, an intermediate reinforcing fiber layer and an inner layer rubber are sequentially arranged from outside to inside in a conventional section; a reinforcing section is provided with a local reinforcing fiber inner layer and a local reinforcing fiber outer layer on the inner side and the outer side of the intermediate reinforcing fiber layer based on the conventional section; and the laying angles of the local reinforcing fiber inner layer and the local reinforcing fiber outer layer are opposite. The air bag mainly bears the flexure and the torsion, and the main body is the lower half part. The conventional section of the application adopts a three-layer structure, the air bag is thinner, the transient response is faster, the dynamic stiffness hysteresis curve is narrow, the high-frequency characteristics are excellent, the demand of the large torsion angle is met, the local reinforcing fiber inner layer and the local reinforcing fiber outer layer are formed by being bonded together due to the process requirement, the two layers form a rhombic grid, the rhombic deformation characteristics are utilized, the reinforcing fiber layer is constrained during the vulcanization expansion process, the reinforcing fiber layer can be uniformly expanded, and the demand of the large load and the high use internal pressure is met.

Description

Technical Field

[0001] This invention relates to the field of air spring technology for passenger vehicles, specifically a partially multi-layered single-layer sleeve-type air spring and its manufacturing method. Background Technology

[0002] With the development of new energy vehicles and increasingly fierce competition, in order to win the market and gradually improve the cost-effectiveness of vehicles, vehicle body size is constantly increasing. To adapt to the relatively narrow roads in urban areas and improve turning ability, turning radii are gradually decreasing, and even rear-wheel steering is being implemented. This places higher demands on the core component of air suspension, the sleeve-type air spring: it must be able to withstand heavy loads, high operating internal pressure (increasing by approximately 40%), excellent high-frequency characteristics (fast transient response, thin airbag), and withstand large torsional angles. Currently, conventional double-layer and single-layer curtain airbags cannot meet these requirements.

[0003] CN219119696U discloses a partially multilayered rubber airbag and a sleeve-type air spring, comprising a rubber airbag, which includes: a rubber layer comprising an inner rubber layer and an outer rubber layer; and a reinforcing fiber layer disposed between the inner and outer rubber layers, comprising an inner reinforcing fiber layer and an outer reinforcing fiber layer, with several locally reinforced fiber layers partially disposed between the inner and outer reinforcing fiber layers. This invention adds locally reinforced fiber layers to the existing two-layer reinforcing fiber layers, enabling the same airbag to meet the requirements of high operating pressure and high burst strength for the unconstrained portion of the air spring, as well as good sweep frequency characteristics for the constrained bending portion. This solution, using two layers of reinforcing fiber sandwiching a single locally reinforced fiber layer, cannot meet the requirements of high load, high operating internal pressure (increased by approximately 40%), excellent high-frequency characteristics (fast transient response, thin airbag), and the ability to withstand large torsional angles under the aforementioned operating conditions. Summary of the Invention

[0004] The technical problem to be solved by this invention is how to simplify the airbag structure while improving airbag performance.

[0005] The present invention solves the above-mentioned technical problems through the following technical means:

[0006] A partially multi-layered single-layer sleeve-type air spring includes a conventional section and a reinforcing section. The conventional section consists of an outer rubber layer, a middle reinforcing fiber layer, and an inner rubber layer, arranged sequentially from the outside in. The reinforcing section is constructed by adding a locally reinforcing fiber inner layer and a locally reinforcing fiber outer layer to the inner and outer sides of the middle reinforcing fiber layer, respectively, based on the conventional section. The laying angles of the locally reinforcing fiber inner layer and the locally reinforcing fiber outer layer are opposite. The lower half (a single-layer 0-degree middle reinforcing fiber layer) is the main component of the air spring that withstands flexure and torsion. The conventional section of this invention adopts a 3-layer structure, resulting in a thinner air spring, faster transient response, and a narrower dynamic stiffness hysteresis curve, meeting the requirements for excellent high-frequency characteristics and large torsional angles.

[0007] The inner and outer layers of locally reinforced fibers are bonded together due to process requirements. These two layers form a rhomboid mesh. Utilizing the rhomboid deformation characteristics, the reinforcing fiber layer is constrained during the vulcanization expansion process, which enables the reinforcing fiber layer to expand evenly. This satisfies the requirements for thinner airbags, faster transient response, narrower dynamic stiffness hysteresis curve, excellent high-frequency characteristics, and large torsional angles.

[0008] Furthermore, the fibers of the locally reinforced inner layer and the locally reinforced outer layer are interwoven to form a rhomboid structure.

[0009] Furthermore, the fiber orientation of the intermediate reinforcing fiber layer is different from that of the local reinforcing fiber inner layer and the local reinforcing fiber outer layer.

[0010] Furthermore, the specifications of the intermediate reinforcing fiber layer may differ from those of the locally reinforcing fiber inner layer and the locally reinforcing fiber outer layer, depending on the burst strength and load capacity requirements of the air spring assembly.

[0011] This invention also provides a method for manufacturing a partially multi-layered single-layer sleeve-type air spring, applied to the aforementioned airbag; comprising the following steps:

[0012] Step 1, Inner rubber layer: Cut rectangular pieces of inner rubber to the correct size and apply them evenly to the molding head;

[0013] Step 2: Forming a locally reinforced fiber inner layer: The parallelogram-shaped rubber curtain is evenly attached to the inner rubber layer to form a locally reinforced fiber inner layer.

[0014] Step 3, intermediate reinforcing fiber layer forming: The rectangular rubber curtain is evenly applied to the inner rubber layer and the local reinforcing fiber inner layer to form the intermediate reinforcing fiber layer;

[0015] Step 4: Forming the outer layer of locally reinforced fibers: The parallelogram-shaped adhesive fabric, at the opposite angle to the inner layer of locally reinforced fibers, is evenly attached to the middle reinforcing fiber layer.

[0016] Step 5: Outer rubber molding: Finally, a rectangular outer rubber layer is evenly covered on the surface to form a semi-finished product.

[0017] Further, methods for shaping semi-finished products:

[0018] Step 6, semi-finished product shaping: The equipment provides a conical expansion support force inside the cylindrical semi-finished product, which expands the semi-finished product into a conical shape in an orderly and uniform manner. After the semi-finished product is shaped, the middle reinforcing fiber layer expands uniformly under the action of the rhomboid deformation characteristics formed by the bonding state between the local reinforcing fiber inner layer and the local reinforcing fiber.

[0019] Step 7: Finally, place the formed semi-finished product into the vulcanization mold of the leather bag, and vulcanize and set it by heating and pressurizing.

[0020] Furthermore, in step 2, the end of the locally reinforced fiber inner layer is flush with the end of the inner rubber layer.

[0021] Furthermore, in step 4, the end of the outer layer of the local reinforcing fiber is flush with the end of the middle reinforcing fiber layer.

[0022] The advantages of this invention are:

[0023] The main body of the airbag that can withstand bending and torsion is the lower half (a single-layer 0-degree intermediate reinforcing fiber layer). The conventional section of this invention adopts a 3-layer structure, making the airbag thinner, with a faster transient response and a narrower dynamic stiffness hysteresis curve, meeting the requirements for excellent high-frequency characteristics and large torsion angles.

[0024] Due to process requirements, a locally reinforced inner layer and a locally reinforced outer layer are bonded together. These two layers form a rhomboid mesh. Utilizing the deformation characteristics of the rhomboid shape, the reinforcing fiber layer is constrained during vulcanization expansion, allowing the reinforcing fiber layer to expand uniformly. This results in a thinner airbag, faster transient response, and a narrower dynamic stiffness hysteresis curve, meeting the requirements for excellent high-frequency characteristics and large torsional angles. Attached Figure Description

[0025] Figure 1 This is a schematic cross-sectional view of the air spring in an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the cross-sectional structure of the conventional section and the reinforced section of the air spring in an embodiment of the present invention;

[0027] Figures 3 to 7 This is a schematic diagram illustrating the manufacturing process of a semi-finished air spring in an embodiment of the present invention;

[0028] Figure 8 This is a schematic diagram of the semi-finished air spring in an embodiment of the present invention;

[0029] Figure 9 This is a fatigue test data table for the air spring in the embodiments of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] This embodiment describes a partially multi-layered single-layer sleeve-type air spring, such as... Figure 1 , Figure 2 As shown, the airbag includes a standard section and a reinforced section. The standard section's intermediate reinforcing fiber layer H2 consists of an inner rubber layer 2 and an outer rubber layer 6, with a complete intermediate reinforcing fiber layer 4 distributed parallel to the axial direction (0° refers to the angle between the fiber direction of the intermediate reinforcing fiber layer and the rotation center axis of the airbag). This 0° intermediate reinforcing fiber layer 4 runs through the entire airbag height H. The airbag's intermediate reinforcing fiber layer H2 consists of only one 0° intermediate reinforcing fiber layer, plus the inner rubber layer 2 and the outer rubber layer 6, making the airbag section (H2) composed of only three layers of material, very thin. When the shock absorber 18 reciprocates axially in the direction of its axis, the airbag 1 needs to exhibit good sweep frequency characteristics and comfort. That is, it needs to improve the transient response of the air spring, have a narrow dynamic stiffness hysteresis curve, and especially demonstrate good high-frequency vibration filtering. Simultaneously, it needs to meet the requirement that the vehicle, in order to achieve a small turning radius, must have a large turning angle, resulting in a large torsional angle for the air spring shock absorber 18. Under this condition, the airbag bears large torsional deformation. With a single 0° intermediate reinforcing fiber layer and 4 airbags, it can meet the long service life requirements under such working conditions.

[0032] —The three-layer intermediate reinforcing fiber layer H1 of the airbag consists of an inner rubber layer 2, an outer rubber layer 6, an intermediate reinforcing fiber layer 4 with a 0° angle in between, and locally reinforcing fiber inner layers 3 and locally reinforcing fiber outer layers 5 added to the inner and outer sides of the intermediate reinforcing fiber layer 4 with a 0° angle, respectively. This five-layer structure results in a very thick airbag wall, capable of meeting the increased clamping and pull-out forces required for high loads and high internal pressure (an increase of approximately 40%). The large clamping force causes significant compressibility changes in the airbag wall, leading to microscopic vibrations and wear during air spring operation. The thick-walled airbag with its five layers ensures a secure assembly even under these complex conditions.

[0033] The airbag in this embodiment can solve the problem of operating environments with large torsional angles: as vehicles continue to increase in size, in order to adapt to the relatively narrow roads in urban areas, improve the vehicle's turning ability, gradually reduce the turning radius, and even provide rear-wheel steering. Previous double-layer rubber airbags with intermediate reinforcing fiber layers could not adapt to this condition—their fatigue life was not up to standard—and their service life was short. The airbag of this application has its lower half (a single-layer 0-degree intermediate reinforcing fiber layer) as the main body for bearing flexure and torsion.

[0034] The airbag mentioned in the background technology, which uses two layers of intermediate reinforcing fiber in its flexural and torsional section, only achieved about 22% of the required lifespan in laboratory rapid fatigue life tests (experiments to calibrate whether the airbag meets its service life requirements). However, the airbag in this embodiment uses a single layer of 0-degree intermediate reinforcing fiber in its flexural and torsional section. Upon reaching 100% lifespan testing, dissection analysis showed the airbag to be intact, indicating a significant improvement. Specific experimental data can be found in [link to relevant documentation]. Figure 9 .

[0035] The specific method for manufacturing the aforementioned airbag is as follows:

[0036] The key to manufacturing this airbag lies in the semi-finished product molding (formation of the blank before vulcanization) and the semi-finished product shaping before vulcanization:

[0037] Semi-finished product process method:

[0038] Step 1, Inner rubber layer 2: as shown Figure 3 As shown, the rectangular inner layer rubber 2, cut to the correct size, is evenly attached (wrapped and rolled up by an automatic forming device) to the forming head (22) (mold);

[0039] Step 2, forming the locally reinforced inner fiber layer 3: as shown Figure 4 As shown, the parallelogram-shaped rubber curtain (including the locally reinforced inner layer 3) is evenly attached (rolled up and wrapped by an automatic forming device) to the inner rubber layer 2, with the right end of the locally reinforced inner layer 3 flush with the right end of the inner rubber layer 2.

[0040] Step 3, 0° intermediate reinforcing fiber layer 4 molding: as follows Figure 5 As shown, a rectangular rubberized fabric (including a 0° intermediate reinforcing fiber layer 4) is evenly applied (wound and wrapped by an automatic forming device) to the inner rubber layer 2 and the locally reinforcing fiber inner layer 3.

[0041] Step 4, Forming the locally reinforced outer fiber layer 5: (e.g.) Figure 6As shown, the parallelogram-shaped rubberized fabric (including the outer layer 5 of locally reinforcing fibers) is at the opposite angle to the inner layer 3 of locally reinforcing fibers (that is, the two layers of locally reinforcing fibers at the same angle are mirror images of the axis of the forming head), and is evenly attached (wound and wrapped by the automatic forming equipment) to the 0° intermediate reinforcing fiber layer 4. The right end of the outer layer 5 of locally reinforcing fibers is flush with the right end of the 0° intermediate reinforcing fiber layer 4.

[0042] Step 5, outer rubber layer 6 molding: as shown Figure 7 As shown, finally, a rectangular outer layer of rubber 6 is evenly covered on the surface, and the semi-finished product is formed.

[0043] Semi-finished product shaping method:

[0044] Step 6, semi-finished product shaping: such as Figure 8 As shown, through the equipment (tooling), a conical expansion support force is provided inside the cylindrical semi-finished product (see: before the semi-finished product is shaped), which expands the semi-finished product into a conical shape in an orderly and uniform manner (at this time, the semi-finished product is similar to the vulcanization mold cavity). After the semi-finished product is shaped, the 0° intermediate reinforcing fiber layer 4 in the middle expands uniformly under the action of the rhomboid variability in the bonded state formed by the local reinforcing fiber inner layer 3 and the local reinforcing fiber outer layer 5—the 0° intermediate reinforcing fiber layer 4 is evenly distributed in proportion.

[0045] Step 7: Finally, place the formed semi-finished product into the vulcanization mold of the leather bag, and vulcanize and set it by heating and pressurizing.

[0046] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A partially multi-layered single-layer sleeve-type air spring, comprising a conventional section and a reinforcing section; characterized in that, The conventional section consists of an outer rubber layer (6), a middle reinforcing fiber layer (4), and an inner rubber layer (2) arranged sequentially from the outside to the inside. The reinforced section is formed by adding a local reinforcing fiber inner layer (3) and a local reinforcing fiber outer layer (5) to the inner and outer sides of the middle reinforcing fiber layer (4) respectively, based on the conventional section. The local reinforcing fiber inner layer (3) and the local reinforcing fiber outer layer (5) are laid at opposite angles. The fibers of the local reinforcing fiber inner layer (3) and the local reinforcing fiber outer layer (5) are interwoven into a rhomboid structure. The fiber orientation of the intermediate reinforcing fiber layer (4) forms an angle of 0° with the rotation center axis of the airbag, and the 0° intermediate reinforcing fiber layer (4) extends through the entire height H of the airbag.

2. The partially multi-layered single-layer sleeve-type air spring according to claim 1, characterized in that, The fiber orientation of the intermediate reinforcing fiber layer (4) is different from that of the local reinforcing fiber inner layer (3) and the local reinforcing fiber outer layer (5).

3. A method for manufacturing a partially multi-layered single-layer sleeve-type air spring, used to manufacture the air spring according to any one of claims 1 to 2; characterized in that, Includes the following steps: Step 1, Inner rubber (2): Cut a rectangular inner rubber (2) to the correct size and attach it evenly to the molding head (22); Step 2, forming a locally reinforced fiber inner layer (3): a parallelogram-shaped rubber curtain is evenly attached to the inner rubber layer (2) to form a locally reinforced fiber inner layer (3). Step 3, intermediate reinforcing fiber layer (4) forming: The rectangular rubber curtain is evenly attached to the inner rubber layer (2) and the local reinforcing fiber inner layer (3) to form the intermediate reinforcing fiber layer (4). Step 4: Forming the outer layer of locally reinforced fiber (5): The parallelogram-shaped adhesive fabric is at the opposite angle to the inner layer of locally reinforced fiber (3) and is evenly attached to the middle reinforced fiber layer (4). Step 5, Outer rubber (6) molding: Finally, a rectangular outer rubber (6) is evenly covered on the surface to form a semi-finished product.

4. The method for manufacturing a partially multi-layered single-layer sleeve-type air spring according to claim 3, characterized in that, Semi-finished product shaping method: Step 6, semi-finished product shaping: The equipment provides a conical expansion support force inside the cylindrical semi-finished product, which expands the semi-finished product into a conical shape in an orderly and uniform manner. After the semi-finished product is shaped, the middle reinforcing fiber layer (4) expands uniformly under the action of the rhomboid variability in the bonded state formed by the local reinforcing fiber inner layer (3) and the local reinforcing fiber outer layer (5). Step 7: Finally, place the formed semi-finished product into the vulcanization mold of the leather bag, and vulcanize and set it by heating and pressurizing.

5. The method for manufacturing a partially multi-layered single-layer sleeve-type air spring according to claim 3, characterized in that, In step 2, the end of the locally reinforced fiber inner layer (3) is flush with the end of the inner rubber layer (2).

6. The method for manufacturing a partially multi-layered single-layer sleeve-type air spring according to claim 3, characterized in that, In step 4, the end of the local reinforcing fiber outer layer (5) is flush with the end of the intermediate reinforcing fiber layer (4).

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