CN112943788B - Carbon fiber composite ball joint and connecting method thereof - Google Patents
Carbon fiber composite ball joint and connecting method thereof Download PDFInfo
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- CN112943788B CN112943788B CN202110102850.2A CN202110102850A CN112943788B CN 112943788 B CN112943788 B CN 112943788B CN 202110102850 A CN202110102850 A CN 202110102850A CN 112943788 B CN112943788 B CN 112943788B
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- shaped screw
- ball head
- fiber composite
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- 229920000049 Carbon (fiber) Polymers 0.000 title claims abstract description 74
- 239000004917 carbon fiber Substances 0.000 title claims abstract description 74
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 title claims abstract description 68
- 239000002131 composite material Substances 0.000 title claims abstract description 57
- 238000000034 method Methods 0.000 title claims abstract description 36
- 239000003292 glue Substances 0.000 claims abstract description 11
- 239000000463 material Substances 0.000 claims abstract description 11
- 238000010276 construction Methods 0.000 claims abstract description 10
- 239000003822 epoxy resin Substances 0.000 claims abstract description 8
- 229920000647 polyepoxide Polymers 0.000 claims abstract description 8
- 239000011248 coating agent Substances 0.000 claims description 3
- 238000000576 coating method Methods 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims 1
- 238000007711 solidification Methods 0.000 abstract description 4
- 230000008023 solidification Effects 0.000 abstract description 4
- 239000002184 metal Substances 0.000 description 8
- 238000000465 moulding Methods 0.000 description 4
- 238000004026 adhesive bonding Methods 0.000 description 3
- 238000005553 drilling Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 2
- 238000004804 winding Methods 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Abstract
The invention discloses a carbon fiber composite ball joint node and a connecting method thereof. The ball joint comprises a ball head, a T-shaped screw and a concave nut, all of which are made of carbon fiber materials, the ball head is of a hollow sphere structure, a plurality of long holes are formed in the ball head, the length of each long hole is larger than the width of each long hole, and the T-shaped screw and the concave nut are installed in one long hole and used for connecting a pipe fitting. The connection method is as follows: firstly, the T-shaped screw and the concave nut are used for slightly clamping the ball head, then the direction of the axis of the T-shaped screw is adjusted to a design value, finally, the concave nut is screwed down, and epoxy resin glue is coated and cured at the thread engagement position and the contact position of the concave nut and the ball head. The invention does not need to support and assist the solidification of the integral truss by other structures, can greatly simplify the construction conditions, reduces the construction period, and has important significance for the field construction of a large truss structure.
Description
Technical Field
The invention relates to the technical field of composite materials, in particular to a structure, a forming method and a connecting method of a carbon fiber composite material ball joint node.
Background
Compared with the traditional steel, the carbon fiber composite material has the advantages of high specific stiffness and high specific strength. The carbon fiber composite material is applied to a large astronomical telescope, so that the weight and driving power consumption of the telescope are reduced, and the self-vibration frequency and the pointing speed of the telescope are improved. In a large truss structure of a large astronomical telescope, the connection technology of the carbon fiber composite material nodes and the pipe fittings is a key technology of truss forming. The nodes of the large truss of the large astronomical telescope have the following characteristics: 1) the number of the pipes connected by the single node is more than 3, the typical number of the pipes is 8 to 10, 2) the number of the pipes of the carbon fiber composite material connected by different nodes can be different, and 3) the angles between the pipe connection positions of the different nodes and the pipes are almost different.
Common connection methods of the carbon fiber composite pipe fitting and the joint are a glue joint method, a drilling connection method, a metal embedding method and a forming thread connection method. The gluing method adopts glue to bond and solidify the carbon fiber composite pipe fitting to be connected with the node, the strength of the glue is generally far lower than that of the carbon fiber composite material, the gluing position is easy to become a weak link of the integral carbon fiber composite material structure, the gluing solidification time is long, and the integral structure forming speed is slow. The drilling connection method is to cut through holes or screw holes on the nodes of the carbon fiber composite materials to be connected in a machining mode, the carbon fiber composite material pipe fittings are connected with the nodes by fasteners from the openings, the drilling connection method can cut off part of carbon fibers, and the openings are easy to form weak links of the whole carbon fiber composite material structure. The embedded metal method is characterized in that metal parts are embedded when the carbon fiber composite material nodes and the pipe fittings are formed, connecting structures such as threads and flanges are arranged on the metal parts, the carbon fiber composite material nodes and the pipe fittings are connected through the connecting structures, and the embedded metal method can increase the weight of the whole structure and reduce the specific strength and the specific rigidity of the structure due to the fact that the metal and carbon fiber composite materials are required to be embedded in the metal parts, and the temperature adaptation range of the whole structure is limited due to the fact that the thermal expansion coefficients of the metal and the carbon fiber composite materials are different. The method of directly manufacturing the thread and connecting by means of the thread when the carbon fiber composite material node is molded is referred to as a molded thread connecting method, the processing quality of the molded thread depends on a thread structure and a molding process, the axis angle of the molded thread after being processed is not adjustable, different nodes may need different molds for molding, the processing difficulty of the molded thread is higher at present, the quality of the thread is low, and the yield of the carbon fiber composite material node structure is affected.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a structure, a forming method and a connecting method of a carbon fiber composite material ball joint node. The method provided by the invention can fully exert the performance characteristics of the carbon fiber composite material, accelerate the integral forming speed of the carbon fiber composite material truss and ensure the specific strength and the specific rigidity of the integral structure.
In order to achieve the above purpose, the present invention provides the following technical solutions:
The utility model provides a carbon fiber composite material bulb node, includes bulb, T type screw rod and concave nut, bulb, T type screw rod and concave nut all adopt carbon fiber material, the bulb is hollow sphere structure, be provided with a plurality of elongated hole on the bulb, the length of elongated hole is greater than the width, and the quantity of elongated hole is the same with the pipe fitting quantity of bulb pre-connection, and the position of elongated hole is decided by the pipe fitting position and the angle of bulb pre-connection, a T type screw rod and a concave nut are installed to an elongated hole for connect a pipe fitting.
Further, the ball head is divided into two layers, namely an inner ball head and an outer ball head, the outer ball head is of a whole ball structure and is formed by tightly winding a continuous carbon fiber material outside the inner ball head, and the long holes penetrate through the inner layer and the outer layer of the ball head.
Further, the inner sphere consists of two hemispheric structures.
Further, the inner layer ball head adopts an inner die and an outer die to extrude and shape the carbon fiber composite material: installing a corresponding strip hole plug at the position of the inner die corresponding to the strip hole, then layering the carbon fiber composite material on the inner die, extruding the outer die to the inner die after layering, and solidifying and forming according to the standard process of the carbon fiber composite material.
Further, the T-shaped screw comprises an upper section, a middle section and a lower section, namely an upper section structure, a middle section structure and a lower section structure, and the carbon fibers are continuous in the upper section, the middle section and the lower section of the T-shaped screw.
Further, the lower surface of the upper section structure is a spherical surface, and the diameter of the spherical surface is the same as the inner diameter of the ball head; the outer part of the middle section structure is cylindrical, the middle section structure penetrates through the long hole, and the sizes of the middle section structure and the long hole allow the T-shaped screw to deflect within a preset axial angle range in the long hole; the lower section structure is provided with external threads for installing the concave nut and the connecting pipe fitting.
Further, one end face of the concave nut is a concave spherical surface, and the diameter of the concave spherical surface is equal to the outer diameter of the ball head.
A connection method of a carbon fiber composite material ball joint comprises the following steps:
1) Clamping position
Inserting the upper section structure of the T-shaped screw rod into the long hole of the ball head until the upper section completely enters the inner space of the inner ball head, and rotating the T-shaped screw rod around the axis of the T-shaped screw rod to clamp the upper section structure of the T-shaped screw rod in the long hole of the ball head;
2) Light clamp
Maintaining the relative position relation between the T-shaped screw and the ball head, screwing the concave surface of the concave nut into the T-shaped screw opposite to the ball head, and rotating the concave nut to enable the T-shaped screw and the concave nut to gently clamp the ball head;
3) Fine tuning
Adjusting the axis direction of the T-shaped screw to a design value, maintaining the upper section structure of the T-shaped screw to be clamped in the long hole of the ball head in the adjusting process, and coating epoxy resin glue at the meshing position of the T-shaped screw and the concave nut and the contact position of the concave nut and the ball head after the axis direction of the T-shaped screw is adjusted;
4) Fixing
And (5) screwing the concave nut and curing the epoxy resin glue.
Compared with the prior art, the invention has the beneficial effects that:
the carbon fibers of the carbon fiber composite material ball joint nodes are continuous and are not cut off, so that the mechanical properties of the carbon fibers can be fully exerted.
The carbon fiber composite ball joint node uses the same carbon fiber material, and has good structural strength consistency and material thermal expansion coefficient consistency.
According to the carbon fiber composite ball joint, the types and the number of the ball head dies can be greatly reduced through the size configuration of the long holes of the ball head and the cylindrical sections of the T-shaped screw.
The connecting method of the carbon fiber composite material ball joint nodes does not need to support and assist the solidification of the integral truss by other structures, can greatly simplify construction conditions, reduces construction period, and has important significance for site construction of a large truss structure of several tens of meters.
Drawings
FIG. 1 is a schematic view of a ball head, T-screw and female nut according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of a method for forming an inner ball of a ball head according to an embodiment of the invention.
The marks in the figure: 1. ball head; 2. a T-shaped screw; 3. a female nut; 4. an outer mold; 5. a strip hole plug; 6. an inner mold; 7. an inner layer ball head; 8. and an outer layer ball head.
Detailed Description
The invention is described in further detail below with reference to the accompanying drawings.
This embodiment provides a carbon fiber composite ball bond as shown in fig. 1. The carbon fiber composite ball joint comprises a ball head 1, a T-shaped screw 2 and a concave nut 3. The bulb 1, T type screw rod 2 and concave nut 3 all adopt carbon fiber material, and bulb 1 is hollow sphere structure, is provided with a plurality of elongated hole on the bulb 1, and the length of elongated hole is greater than the width, and long limit and broadside are best rounded, and the quantity of elongated hole is the same with the pipe fitting quantity that the bulb is connected in advance, and the quantity of elongated hole is specifically 5 in this embodiment, and the position of elongated hole is by the pipe fitting position and the angle decision of bulb pre-connection. An elongated bore is provided with a T-screw 2 and a female nut 3 for connecting a pipe. One end face of the concave nut 3 is concave. The carbon fiber of the carbon fiber composite material ball joint node is continuous and is not cut off, so that the mechanical property of the carbon fiber can be fully exerted; the carbon fiber composite ball joint node uses the same carbon fiber material, and has good structural strength consistency and material thermal expansion coefficient consistency; the carbon fiber composite ball nodes are configured through the sizes of the long holes of the ball and the cylindrical sections of the T-shaped screw, so that the variety and the number of ball molds can be greatly reduced.
In this embodiment, the ball head 1 is divided into two layers, namely an inner ball head 7 and an outer ball head 8, the outer ball head 8 is of a whole ball structure, and is formed by tightly winding a continuous carbon fiber material outside the inner ball head 7, the inner diameter of the outer ball head is equal to the outer diameter of the inner ball head, the outer surface of the outer ball head is finished, and a long hole penetrates through the inner layer and the outer layer of the ball head 1.
As shown in fig. 2, in this embodiment, the inner ball 1 may be divided into two hemispheres during molding, the inner diameters and the outer diameters of the two hemispheres of the inner ball are the same, the two hemispheres are reserved with long holes, the inner surface is ground after solidification, and the inner surface of the inner ball 7 is finished. And (5) finishing the outer surface of the outer ball head 8. The inner ball head 7 adopts the inner die 6 and the outer die 4 to extrude and shape the carbon fiber composite material: and installing a corresponding strip hole plug 5 at the position of the inner mold 6 corresponding to the strip hole, then layering the carbon fiber composite material on the inner mold 6, extruding the outer mold 4 to the inner mold 6 after layering, and curing and forming according to the standard process of the carbon fiber composite material.
In this embodiment, the T-shaped screw 2 includes an upper section, a middle section, and a lower section, that is, an upper section structure, a middle section structure, and a lower section structure, where the carbon fibers are continuous. The T-shaped screw is preferably manufactured by integrally molding a die and is of a solid structure. Specifically, the lower surface of the upper section structure is a spherical surface, the spherical surface is finished, the diameter of the spherical surface is the same as the inner diameter of the inner-layer ball head, the cross section of the upper section structure is in a strip shape, the long side and the wide side are preferably rounded, the length of the strip shape is smaller than the length of the long hole of the ball head and larger than the width of the long hole of the ball head, the width of the strip shape is smaller than the width of the long hole of the ball head, and the strip shape can enter the long hole of the ball head; the outer part of the middle section structure is cylindrical, the diameter of the cylinder is smaller than the width of the long hole of the ball head, the diameter of the cylinder is required to meet the requirements of structural strength and rigidity, in addition, the relation between the diameter of the cylinder and the width of the long hole of the ball head influences the adjusting range of the cylinder in the long hole of the ball head, so that the quantity of the ball heads with specific long hole positions is influenced, the variety and quantity of ball head dies are influenced, the size of the middle section structure and the size of the long hole allow the T-shaped screw 2 to deflect within the preset axial angle range in the long hole, for example, the size of the cylinder and the size of the long hole allow the axial deflection angle range of the T-shaped screw in the long hole of the ball head to be +/-1.1 DEG in the embodiment; the lower section structure is provided with external threads, and the external threads are used for installing the concave nut and connecting the pipe fitting.
In this embodiment, the concave surface of the concave nut 3 is preferably a concave spherical surface, and the concave spherical surface is finished, and the diameter of the concave spherical surface is equal to the outer diameter of the outer ball. The external diameter of the female nut 3 is at least larger than the width of the elongated hole of the ball head, preferably the external diameter of the nut is larger than the length of the elongated hole of the ball head, and the threads of the nut are engaged with the threads of the T-shaped screw. The nut is preferably formed integrally with the die.
The cross-sectional shapes of the long hole of the ball head and the upper section of the T-shaped screw rod can be elliptic, waist-shaped, rectangular and the like, and in the embodiment, the cross-sectional shapes are rectangular with four corners rounded off.
The embodiment further provides a method for connecting the carbon fiber composite ball nodes shown in fig. 2. The connection method comprises the following 4 steps:
1) And (5) clamping. The upper section of the T-shaped screw rod is inserted into the long hole of the ball head until the upper section completely enters the inner space of the inner ball head, and the T-shaped screw rod is rotated by 90 degrees around the axis of the T-shaped screw rod, so that the upper section structure of the T-shaped screw rod is clamped in the long hole of the ball head.
2) And (5) light clamping. And (3) maintaining the relative position relation between the T-shaped screw and the ball head, screwing the concave nut into the T-shaped screw, wherein the concave nut is in the direction that the concave spherical surface faces the ball head, and rotating the concave nut to enable the T-shaped screw and the concave nut to lightly clamp the ball head.
3) Fine tuning. And adjusting the axis direction of the T-shaped screw to a design value, maintaining the upper section structure of the T-shaped screw to be clamped in the long hole of the ball head in the adjusting process, and coating epoxy resin glue at the meshing position of the T-shaped screw and the concave nut and the contact position of the concave nut and the ball head after the axis direction of the T-shaped screw is adjusted.
4) Fixing. And (5) screwing the concave nut to solidify the epoxy resin glue.
In summary, the carbon fiber composite ball joint comprises a ball, a T-shaped screw and a concave nut, wherein the ball is provided with a plurality of long holes, and one long hole is provided with the T-shaped screw and the concave nut for connecting a pipe fitting. The connecting method of the ball joint point comprises the following steps: firstly, the T-shaped screw and the concave nut are used for slightly clamping the ball head, then the direction of the axis of the T-shaped screw is adjusted to a design value, finally, the concave nut is screwed down, and epoxy resin glue is coated and cured at the thread engagement position and the contact position of the concave nut and the ball head. The carbon fiber composite material ball joint nodes are all made of carbon fiber composite materials, and are high in structural strength and light in weight. The connecting method of the carbon fiber ball joint nodes can greatly simplify construction conditions, reduce construction period and has important significance particularly for site construction of a large truss structure of several tens of meters.
The above description is only of the preferred embodiments of the present invention, and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. The utility model provides a carbon fiber composite material bulb node which characterized in that, includes bulb, T type screw rod and concave nut, bulb, T type screw rod and concave nut all adopt carbon fiber material, the bulb is hollow sphere structure, be provided with a plurality of elongated hole on the bulb, the length of elongated hole is greater than the width, the quantity of elongated hole is the same with the pipe fitting quantity that the bulb is connected in advance, the position of elongated hole is by the pipe fitting position and the angle that the bulb is connected in advance, a T type screw rod and a concave nut are installed to an elongated hole for connect a pipe fitting; the T-shaped screw comprises an upper section structure, a middle section structure and a lower section structure, wherein the cross section of the upper section structure is of a strip shape, the length of the strip shape is smaller than that of the long hole of the ball head and larger than the width of the long hole of the ball head, and the width of the strip shape is smaller than that of the long hole of the ball head.
2. The carbon fiber composite ball stud according to claim 1 wherein the ball stud is divided into two layers, an inner ball stud and an outer ball stud, the outer ball stud being of a full ball construction formed by tightly wrapping a continuous carbon fiber material around the inner ball stud, the elongated hole penetrating both the inner and outer layers of the ball stud.
3. The carbon fiber composite ball joint according to claim 2 wherein the inner ball consists of two hemispheric structures.
4. The carbon fiber composite ball joint according to claim 3, wherein the inner ball is formed by extruding the carbon fiber composite material through an inner die and an outer die: installing a corresponding strip hole plug at the position of the inner die corresponding to the strip hole, then layering the carbon fiber composite material on the inner die, extruding the outer die to the inner die after layering, and solidifying and forming according to the standard process of the carbon fiber composite material.
5. The carbon fiber composite ball joint according to claim 1 wherein carbon fibers are continuous in the upper, middle and lower three sections of the T-screw.
6. The carbon fiber composite ball joint according to claim 5 wherein the lower surface of the upper structure is a sphere having the same diameter as the inner diameter of the ball; the outer part of the middle section structure is cylindrical, the middle section structure penetrates through the long hole, and the sizes of the middle section structure and the long hole allow the T-shaped screw to deflect within a preset axial angle range in the long hole; the lower section structure is provided with external threads for installing the concave nut and the connecting pipe fitting.
7. The carbon fiber composite ball joint according to claim 1, wherein an end face of the female nut is a concave spherical surface having a diameter equal to an outer diameter of the ball.
8. A method of joining carbon fiber composite ball nodes of any one of claims 1 to 7, comprising the steps of:
1) Clamping position
Inserting the upper section structure of the T-shaped screw rod into the long hole of the ball head until the upper section completely enters the inner space of the inner ball head, and rotating the T-shaped screw rod around the axis of the T-shaped screw rod to clamp the upper section structure of the T-shaped screw rod in the long hole of the ball head;
2) Light clamp
Maintaining the relative position relation between the T-shaped screw and the ball head, screwing the concave surface of the concave nut into the T-shaped screw opposite to the ball head, and rotating the concave nut to enable the T-shaped screw and the concave nut to gently clamp the ball head;
3) Fine tuning
Adjusting the axis direction of the T-shaped screw to a design value, maintaining the upper section structure of the T-shaped screw to be clamped in the long hole of the ball head in the adjusting process, and coating epoxy resin glue at the meshing position of the T-shaped screw and the concave nut and the contact position of the concave nut and the ball head after the axis direction of the T-shaped screw is adjusted;
4) Fixing
And (5) screwing the concave nut and curing the epoxy resin glue.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110102850.2A CN112943788B (en) | 2021-01-26 | Carbon fiber composite ball joint and connecting method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110102850.2A CN112943788B (en) | 2021-01-26 | Carbon fiber composite ball joint and connecting method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112943788A CN112943788A (en) | 2021-06-11 |
| CN112943788B true CN112943788B (en) | 2024-07-05 |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105352398A (en) * | 2015-12-14 | 2016-02-24 | 重庆赫杰精密机械有限公司 | Carbon fiber pipe connection device used for automobile testing fixture support |
| CN105947168A (en) * | 2016-06-04 | 2016-09-21 | 郑州中德美游乐设备有限公司 | Multi-rotor manned craft adopting helium balloon to overcome part of gravity |
| CN110510098A (en) * | 2019-08-29 | 2019-11-29 | 赵燕莺 | A kind of carbon fiber truss structure |
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105352398A (en) * | 2015-12-14 | 2016-02-24 | 重庆赫杰精密机械有限公司 | Carbon fiber pipe connection device used for automobile testing fixture support |
| CN105947168A (en) * | 2016-06-04 | 2016-09-21 | 郑州中德美游乐设备有限公司 | Multi-rotor manned craft adopting helium balloon to overcome part of gravity |
| CN110510098A (en) * | 2019-08-29 | 2019-11-29 | 赵燕莺 | A kind of carbon fiber truss structure |
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