Lightweight composite material self-lubricating rotatable spherical hinge and preparation method thereof

Abstract

The invention relates to a lightweight composite material self-lubricating rotatable spherical hinge and a preparation method thereof, the rotatable spherical hinge comprises an outer sleeve and an elastic body pressed in the outer sleeve, and the elastic body is of a structure formed by attaching an elastic material to the outside of a mandrel; the outer sleeve is of a structure formed in the mode that continuous fibers are woven into an outer sleeve framework through three-dimensional weaving, and resin is injected into the outer sleeve framework. According to the outer sleeve of the spherical hinge, after the continuous fibers are woven into the outer sleeve framework, the resin is injected into the outer sleeve framework to form the overall structure of the outer sleeve, and compared with a metal outer sleeve, the mass of the outer sleeve is greatly reduced; in the forming process, a crystal structure and the self-lubricating property of the elastic body can be formed, the surface roughness of the elastic body is extremely low, a high-abrasion-resistant three-dimensional woven continuous fiber net-shaped structure exists in the outer sleeve, abrasion between the elastic body and the composite outer sleeve can be reduced, and the service life of the spherical hinge is prolonged.

Description

Technical Field

[0001] The invention relates to a ball joint and a preparation method thereof, and in particular to a lightweight composite material self-lubricating rotatable ball joint and a preparation method thereof. Background Art

[0002] As a widely used elastic connection component, ball joints are mainly used for flexible connection and vibration shock buffering, and play a role in vibration reduction and noise reduction. The current structure of ball joints is generally an elastomer formed by rubber and metal core shaft pressed into a metal jacket. Therefore, for a ball joint with a rotating function, its rotating surface is mainly the friction between the elastomer and the metal material. The friction loss of the metal material with higher hardness to the elastomer is larger, which seriously affects the service life of the ball joint. At the same time, the metal core shaft and jacket are heavy and cannot meet the current vehicle (especially new energy vehicles) requirements for lightweight products.

[0003] For example, the invention patent with announcement number CN109578429B and name “An elastic ball joint with a rotatable composite core shaft” previously applied by the applicant discloses an elastic ball joint with a rotatable composite core shaft, wherein the core shaft is composed of a basic core shaft of a metal part and a core shaft protrusion of a composite material, which reduces the weight of the ball joint to a certain extent. However, the process is relatively complicated, and the connection between the basic core shaft and the core shaft protrusion made of different materials is relatively difficult.

[0004] There is also an invention patent with authorization announcement number CN111791513B and name "Method for manufacturing a composite core shaft for lightweight ball joints, and lightweight ball joints". The core shaft is made by winding glass fiber on a metal core shaft, and then curing it with resin gel and then machining it. Although it also reduces the weight of the ball joint to a certain extent, it also has the problem of complicated process and difficulty in connecting the base core shaft and the core shaft protrusion made of different materials.

[0005] Moreover, none of the above patents mention the jacket material. If a metal structure is still used, friction between metal and rubber cannot be avoided. Summary of the invention

[0006] In response to the problems that current rotating ball joints are heavy and cause great wear to rubber during friction, the present invention proposes a lightweight composite material self-lubricating rotating ball joint and a preparation method thereof. The skeleton of the outer jacket is woven with highly wear-resistant continuous fibers, which reduces the weight of the ball joint while reducing the wear between the elastomer and the outer jacket.

[0007] The technical means adopted by the present invention to solve the above problems are: a lightweight composite material self-lubricating rotatable ball joint, including a jacket and an elastic body pressed into the jacket, wherein the elastic body is a structure formed by attaching an elastic material to the outside of a core shaft, and the jacket is a structure formed by weaving continuous fibers into a jacket skeleton by three-dimensional weaving, and injecting resin into the jacket skeleton. The jacket formed by continuous fibers and resin materials can reduce both mass and wear between the jacket and the elastic body.

[0008] Furthermore, annular end covers are provided at both ends of the ball joint outer sleeve.

[0009] Furthermore, the end cap is a structure formed by weaving continuous fibers into an end cap skeleton by three-dimensional weaving, and injecting the same resin as that in the outer jacket into the end cap skeleton. The end cap and the outer jacket are made of the same material, which is conducive to the bonding between the end cap and the outer jacket.

[0010] Furthermore, there is a gap between the inner ring of the end cover and the elastic body, and the gap serves as a radial compression deformation space of the ball joint.

[0011] Furthermore, the mandrel is a structure formed by weaving continuous fibers into a mandrel skeleton by three-dimensional weaving and injecting resin into the mandrel skeleton. The mandrel formed by the continuous fibers and the resin material can further reduce the quality of the product.

[0012] A method for preparing a lightweight composite material self-lubricating rotatable ball joint. When preparing the outer jacket, the axial warp yarns are straight continuous fibers, the continuous fibers of the circumferential weft yarns are spirally wound to fix the warp yarns, and the radial continuous fibers are woven in a zigzag shape to wrap the warp yarns and weft yarns to form an outer jacket skeleton. After the zigzag weaving, there are straight continuous fibers in the radial direction, which can provide strong radial mechanical strength.

[0013] Furthermore, a thermosetting resin is injected into the outer shell skeleton, and the outer shell is formed after cooling, so that the thermosetting resin enters between the continuous fibers to form a whole.

[0014] Furthermore, a thermoplastic resin is injected into the outer shell skeleton, and the outer shell is formed after being heated and pressurized for curing, so that the thermoplastic resin enters between the continuous fibers to form a whole.

[0015] Furthermore, when preparing the mandrel, firstly, a rectangular braiding machine is used to braid the continuous fibers into a solid rod-shaped inner core, and then a circular braiding machine is used to braid a sphere on the inner core to form a mandrel skeleton. The mandrel skeleton is braided twice, and mandrels of different shapes can be braided in a targeted manner.

[0016] Furthermore, when the inner core is braided, metal sleeves are embedded at both ends of the inner core, and the outer periphery of the metal sleeves is wrapped with continuous fibers, so that the metal sleeves provide assembly torque.

[0017] Furthermore, a thermosetting resin is injected into the mandrel skeleton, and the mandrel is formed after cooling, so that the thermosetting resin enters between the continuous fibers to form a whole.

[0018] Furthermore, a thermoplastic resin is injected into the core shaft skeleton, and the core shaft is formed after being heated, pressed and cured, so that the thermoplastic resin enters between the continuous fibers to form a whole.

[0019] Furthermore, the end cap is fixed to the end of the outer jacket by means of structural adhesive bonding or hot-melt welding, so as to prevent the elastic body from escaping from the outer jacket.

[0020] The beneficial effects of the present invention are: 1. The outer sleeve of the ball joint of the present invention is woven into an outer sleeve skeleton with continuous fibers, and then resin is injected into the outer sleeve skeleton to form the overall structure of the outer sleeve. Compared with a metal outer sleeve, the mass of the outer sleeve is greatly reduced. At the same time, due to the crystallization characteristics of the polymer composite material in the outer sleeve, a crystal structure and its own self-lubricating properties are formed during the molding process, making its surface roughness extremely low. In addition, there is a highly wear-resistant three-dimensional woven continuous fiber mesh structure in the outer sleeve, which can reduce the wear between the elastomer and the composite outer sleeve and increase the life of the ball joint.

[0021] 2. When weaving the jacket of the present invention, the weft yarn is firstly spirally wound around the straight warp yarn, and then the continuous fiber is used to wrap the warp yarn and the weft yarn in a zigzag shape, so that the jacket after being formed can withstand a relatively large load in all directions.

[0022] 3. The core shaft of the ball joint of the present invention is also prepared by three-dimensional weaving and then injecting resin, which further greatly reduces the mass of the ball joint. At the same time, the ball joint product has higher mechanical properties and significant lightweight effect, and can also achieve the same performance conditions as metal products. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the overall structure of the ball joint in Example 1; Figure 2 It is a schematic diagram of the three-dimensional braided outer jacket of Example 1 after being cut open along the axial direction; Figure 3 This is a schematic diagram of the three-dimensional braided outer jacket of Example 1 along the axial direction; Figure 4 This is a schematic cross-sectional view of a core shaft skeleton of Example 1; Figure 5 This is an overall schematic diagram of the mandrel skeleton of Example 1; Figure 6 This is a cross-sectional schematic diagram of a jacket 1 of the second embodiment; In the figure: 1. outer sleeve, 11. retaining ring, 2. elastic material, 3. core shaft, 31. inner core, 4. end cover, 5. metal sleeve. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with the accompanying drawings. The accompanying drawings are only for illustrative purposes and are only schematic diagrams, not actual pictures, and cannot be understood as limiting the present patent; in order to better illustrate the embodiments of the present invention, some parts of the accompanying drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; it is understandable to those skilled in the art that some well-known structures and their descriptions in the accompanying drawings may be omitted. Embodiment 1

[0025] A lightweight composite material self-lubricating rotatable ball joint and a preparation method thereof, such as Figure 1 As shown, the ball joint includes an outermost outer shell 1, an elastic body pressed into the outer shell 1, and an annular end cap 4 bonded to both ends of the outer shell 1. The elastic body can be formed by vulcanizing natural rubber or special rubber on the surface of the core shaft 3, or by bonding the surface of the core shaft 3 with polyurethane material, that is, the elastic material 2 can be natural rubber, special rubber or polyurethane material. The end cap 4 is made of the same material as the outer shell 1, and is bonded to the inner ring of the rear end cap 4 of the outer shell 1 to reserve a certain space between the elastic body and the end cap 4, so as to prevent the elastic body from axially escaping, and at the same time leave a certain radial compression deformation space for the elastic body.

[0026] The preparation method of the ball joint is as follows: first, the outer sleeve 1, the elastomer and the end cover 4 are separately manufactured, then the elastomer is pressed into the outer sleeve 1, and finally the end cover 4 is fixed to both ends of the outer sleeve 1 by structural adhesive or hot-melt welding.

[0027] The preparation process of the jacket 1 is as follows: the first step is as follows: Figure 2 and Figure 3 As shown, straight continuous fibers are laid axially as warp yarns b, and the length of warp yarns b is the length of jacket 1; continuous fibers are spirally wound circumferentially as weft yarns c, and weft yarns c fix warp yarns b and constrain their density; then continuous fibers c are used to weave in a zigzag shape in the radial direction, wrapping both warp yarns b and weft yarns c to form a jacket skeleton. In the jacket skeleton, there are straight continuous fibers in the axial, radial and circumferential directions, which can provide strong mechanical strength. In the second step, thermosetting resins, such as epoxy systems, phenolic systems, etc., are injected into the jacket skeleton through liquid molding processes such as RTM and HP-RTM, and jacket 1 is formed after pressure-maintaining and cooling; thermoplastic resin systems, such as PA6, etc., can also be introduced into the jacket skeleton through in-situ polymerization, and jacket 1 is formed after heating and pressurizing.

[0028] The preparation process of the mandrel 3 is as follows: Figure 4 and Figure 5As shown, in the first step, a rectangular braiding machine is used to weave a solid rectangular rod-shaped inner core 31 according to actual needs, and during the braiding process, a metal sleeve 5 is wrapped in the continuous fiber at each end of the inner core 31 through its outer periphery to provide assembly torque in the subsequent process. Then a circular braiding machine is used to weave a sphere on the outside of the inner core to obtain a core shaft skeleton. In the second step, a thermosetting resin, such as an epoxy system, a phenolic system, etc., is injected into the core shaft skeleton through liquid molding processes such as RTM and HP-RTM, and the core shaft 3 is formed after pressure cooling; a thermoplastic resin system, such as PA6, can also be introduced into the core shaft skeleton through in-situ polymerization, and the core shaft 3 is formed after heating and pressurizing.

[0029] The preparation process of the end cap 4 is as follows: first, three-dimensionally weave continuous fibers into a ring-shaped sheet structure of a certain thickness to form an end cap skeleton. Second, inject resin into the end cap skeleton using the same material and process as the outer jacket to form the end cap 4. Embodiment 2

[0030] This embodiment is basically the same as the above embodiment, except that: the outer sleeve 1 in the first embodiment is a ring, while in this embodiment, Figure 6 As shown, the jacket 1 is a structure with an annular retaining ring 11 protruding inward at one end, that is, when performing three-dimensional weaving, the structure of an end cover skeleton in the first embodiment is synchronously woven into the jacket skeleton, and then the resin material is synchronously injected to form a jacket 1 structure with a retaining ring 11 at one end. In this way, after the elastomer is pressed into the jacket 1, only the end cover 4 at one end needs to be bonded.

[0031] The above embodiments are only used to illustrate the present invention, rather than to limit the present invention. Technicians in the relevant technical field may make various changes or modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions should also fall within the protection scope of the present invention, and the protection scope of the present invention should be defined by the claims.

Claims

1. A lightweight composite material self-lubricating rotatable ball joint, comprising a jacket (1) and an elastic body pressed into the jacket (1), wherein the elastic body is a structure formed by attaching an elastic material (2) to the outside of a core shaft (3), characterized in that: The jacket (1) is a structure formed by weaving continuous fibers into a jacket skeleton using three-dimensional weaving, and injecting resin into the jacket skeleton.

2. The lightweight composite material self-lubricating rotatable ball joint according to claim 1, characterized in that: Annular end covers (4) are provided at both ends of the ball joint sleeve (1).

3. The lightweight composite material self-lubricating rotatable ball joint according to claim 2, characterized in that: The end cap (4) is a structure formed by weaving continuous fibers into an end cap skeleton using three-dimensional weaving, and injecting the same resin as that in the outer sleeve (1) into the end cap skeleton.

4. The lightweight composite material self-lubricating rotatable ball joint according to claim 2, characterized in that: There is a gap between the inner ring of the end cover (4) and the elastic body.

5. The lightweight composite material self-lubricating rotatable ball joint according to claim 1, characterized in that: The core shaft (3) is a structure formed by weaving continuous fibers into a core shaft skeleton using three-dimensional weaving, and injecting resin into the core shaft skeleton.

6. A method for preparing the lightweight composite material self-lubricating rotatable ball joint according to claim 1, characterized in that: When preparing the jacket (1), the axial warp yarns are straight continuous fibers, the circumferential weft yarns are spirally wound to fix the warp yarns, and the radial continuous fibers are woven in a zigzag pattern to wrap the warp yarns and weft yarns to form a jacket skeleton.

7. The method for preparing a lightweight composite material self-lubricating rotatable ball joint according to claim 6, characterized in that: Injecting a thermosetting resin into the outer shell frame and forming an outer shell (1) after cooling; Alternatively, a thermoplastic resin is injected into the outer shell frame and then heated and pressurized to form the outer shell (1).

8. The method for preparing a lightweight composite material self-lubricating rotatable ball joint according to claim 6, characterized in that: When preparing the mandrel (3), firstly, a rectangular braiding machine is used to braid the continuous fibers into a solid rod-shaped inner core (31), and then a circular braiding machine is used to braid a sphere on the inner core (31) to form a mandrel skeleton; When the inner core (31) is braided, the metal sleeves (5) are embedded at both ends of the inner core (31), and the outer periphery of the metal sleeves (5) is wrapped with continuous fibers.

9. The method for preparing a lightweight composite material self-lubricating rotatable ball joint according to claim 8, characterized in that: Injecting thermosetting resin into the core shaft skeleton and forming the core shaft (3) after cooling; Alternatively, a thermoplastic resin is injected into the core shaft skeleton, and then heated, pressurized and cured to form the core shaft (3).

10. The method for preparing a lightweight composite material self-lubricating rotatable ball joint according to claim 6, characterized in that: The end cover (4) is fixed to the end of the outer sleeve (1) by means of structural adhesive bonding or hot-melt welding.

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