Manufacturing Method and Manufacturing Equipment for the Middle Tube of a Badminton Racket

Abstract

The present invention discloses a manufacturing method for the middle tube of a badminton racket, comprising: preparing a core material mold; winding carbon fiber cloth around the core material mold to form a carbon rod structure; winding a pressure belt outside the carbon rod structure; putting the carbon rod structure wound with the pressure belt and the core material mold together into a pressurizing and heating device for pressurizing and heating to cure and form the carbon rod structure; removing the pressure belt outside the carbon rod structure and extracting the core material mold from the carbon rod structure; and simultaneously discloses a manufacturing device applied to the manufacturing method for the middle tube of the badminton racket. The manufacturing method and manufacturing device for the middle tube of the badminton racket according to the present invention can enable the middle tube not to undergo a grinding process during the manufacturing process, ensure the continuity of carbon fiber inside the middle tube and the integrity of the resin protection layer on the surface of the middle tube, strengthen the curing effect of carbon fiber and resin, reduce the usage amount of carbon fiber, optimize the production process, save the production cost of the middle tube of the badminton racket, and improve the production efficiency.

Description

Technical Field

[0001] The present invention relates to the field of sports equipment, and particularly to a manufacturing method for the middle tube of a badminton racket and a manufacturing device for manufacturing the middle tube of a badminton racket. Background Art

[0002] Badminton is a sport that can be carried out indoors and outdoors. Usually, there are two or four players, divided into two groups, taking turns to hit the feathered ball across the net in the middle of the court with a racket with a handle. Generally, a badminton racket consists of a racket frame, a middle tube, a front sleeve, a handle and other accessories. Among them, the middle tube is one of the very important components of a badminton racket and has a crucial impact on the overall performance and user experience of the badminton racket.

[0003] The middle tubes of badminton rackets with better quality are generally made of carbon fiber materials with superior performance. The commonly used manufacturing method for carbon fiber middle tubes is as follows: First, select a slender iron core mold, wind carbon fiber cloth on the outside of the iron core mold, and wind a tape made of OPP material outside the wound carbon fiber cloth to wrap the iron core and the carbon fiber cloth tightly; then bake the OPP tape at a high temperature. When the OPP material is heated, it will shrink. The shrinkage of the OPP tape will generate pressure, which will further squeeze the wound carbon fiber cloth. At the same time, the epoxy resin between the carbon cloths will cure when heated, so that the carbon fiber cloth cures and forms a rough blank of the middle tube; finally, pull out the iron core mold from the cured rough blank of the middle tube, remove the OPP tape, and then grind the winding traces of the OPP tape on the surface of the rough blank of the middle tube until the surface of the rough blank of the middle tube is flat and smooth and the size specifications meet the requirements of the middle tube, and then the finished product of the middle tube of the badminton racket can be obtained.

[0004] However, this manufacturing method has many problems: First, the pressure generated by the shrinkage of the OPP tape when heated is very limited, and the pressure generated by the shrinkage is unstable, which is not conducive to the curing and forming of the epoxy resin and the carbon fiber cloth, and easily causes the instability of the strength of the middle tube; Second, the shrinkage and extrusion of the OPP tape will cause many indentation marks on the outer surface of the rough blank of the middle tube. In order to remove the indentation marks and obtain a middle tube finished product with a smooth surface, it is necessary to grind off the indentation marks on the surface of the rough blank of the middle tube by grinding, but the grinding process will cause damage and fracture of the carbon fiber on the surface of the middle tube. For carbon fiber with strong directivity, the damage or fracture of the fiber will seriously affect the performance of the fiber, resulting in the inability to fully exert the performance of the carbon fiber in the middle tube; Third, the grinding process will grind off the resin protection layer on the surface of the middle tube, exposing the carbon fiber. When it collides with other objects, it is easy to cause fiber damage and lead to the fracture of the middle tube; Fourth, since grinding is required during the processing of the middle tube, it is necessary to stack about 2%-5% more material structure of standard parts when wrapping the carbon fiber cloth as the material to be ground off to ensure that the middle tube after grinding has qualified dimensions. This method will increase the carbon fiber cloth used for the middle tube and increase the production cost of the middle tube. Summary of the Invention

[0005] The present invention aims to provide a method and equipment for manufacturing a badminton racket tube, which can eliminate the grinding process during the production of the badminton racket tube and improve the strength and impact resistance of the badminton racket tube. The specific technical solution is as follows:

[0006] A method for manufacturing a badminton racket middle tube comprises the following steps:

[0007] Prepare core material mold;

[0008] Rolling the carbon fiber cloth onto the core material mold to form a carbon rod structure;

[0009] Wrapping a pressure tape around the carbon rod structure;

[0010] The carbon rod structure wrapped with the pressure belt and the core material mold are placed together in a pressurized heating device for pressurization and heating to solidify the carbon rod structure;

[0011] Remove the pressure belt outside the carbon rod structure and pull out the core material mold in the carbon rod structure.

[0012] Furthermore, after the pressure belt is wrapped around the carbon rod structure, the first end of the carbon rod structure is sealed so that the pressure belt near the first end of the carbon rod structure is sealed and connected to the core material mold.

[0013] Furthermore, when winding the pressure belt, the pressure belt is sequentially wound from the second end of the carbon rod structure to the first end of the carbon rod structure, and the pressure belt is continued to be wound onto the core material mold near the first end of the carbon rod structure to seal the pressure belt to the core material mold.

[0014] Furthermore, the pressure belt extends from the first end of the carbon rod structure toward the core material mold and is wrapped around 8 mm to 12 mm.

[0015] Furthermore, before the core material mold is placed in the pressurized heating device, a sleeve is connected to the core material mold, the sleeve is fixedly connected to the core material mold, and the core material mold is sent into the pressurized heating device through the sleeve.

[0016] Furthermore, after one end of the sleeve is fixedly connected to the core material mold, the other end of the sleeve is sealed to the inner wall of the pressurized heating device to form a closed space between the inner wall of the pressurized heating device and the outer wall of the sleeve.

[0017] Furthermore, the sleeve is sleeved on the outside of the core material mold and docked with the second end of the carbon rod structure, so that the joint between the sleeve and the second end of the carbon rod structure is sealed.

[0018] Furthermore, a sealing tape is wrapped around the joint between the sleeve and the second end of the carbon rod structure to seal the joint, and the sleeve and the core material mold are connected as a whole.

[0019] Furthermore, the inner diameter of the sleeve is larger than the outer diameter of the core material mold. When the sleeve is sleeved on the outside of the core material mold, an exhaust gap is formed between the inner wall of the sleeve and the outer wall of the core material mold.

[0020] Furthermore, the outer diameter of the rolled carbon rod structure is the same as the outer diameter of the middle tube standard part to be manufactured.

[0021] A badminton racket middle tube manufacturing device is used in the badminton racket manufacturing method described above, comprising a core material mold and a hot pressing device. The core material mold is rolled with material for making the middle tube. The hot pressing device has a receiving chamber formed inside. The core material mold is placed in the receiving chamber of the hot pressing device. The material for making the middle tube is solidified and formed in a heated and pressurized environment.

[0022] Furthermore, the hot pressing device includes a tank body and a tank cover, a tank mouth is provided at one end of the tank body, and the tank cover is provided on the tank mouth of the tank body. An air intake valve is provided on the tank body, and the air intake valve can open or close the air intake channel of the hot pressing device to control the pressure value in the containing chamber. A heating component is provided in the tank body, and the heating component can heat the containing chamber.

[0023] Furthermore, it also includes a sleeve, the interior of the sleeve is hollow, the first end of the sleeve is an opening, the opening is arranged on the outside of the core material mold, and is connected to the material for making the middle tube rolled on the core material mold, and is connected to the core material mold. The core material mold extends into the accommodating chamber in the hot pressing device through the sleeve.

[0024] Furthermore, the inner diameter of the sleeve is larger than the outer diameter of the core material mold, and an exhaust gap is formed between the inner wall of the sleeve and the outer wall of the core material mold.

[0025] Furthermore, the second end of the sleeve is provided with a connecting portion, which can be clamped on the tank mouth of the hot pressing device.

[0026] Furthermore, a through hole is provided on the connecting portion of the sleeve, which is connected to the hollow structure inside the sleeve. An exhaust port is provided on the tank cover of the hot pressing device, and the exhaust port is corresponding to the through hole on the connecting portion of the sleeve.

[0027] The badminton racket middle tube manufacturing method and manufacturing equipment of the present invention have the following advantages:

[0028] 1. It can eliminate the need for grinding during the production process of the badminton racket's center tube, ensuring the continuity of the carbon fibers inside the center tube and the integrity of the resin protective layer on the center tube surface, ensuring that the excellent performance of the carbon fibers is fully utilized and improving the conductivity of the center tube;

[0029] 2. It can increase the molding pressure of the badminton racket tube, strengthen the curing effect of carbon fiber and resin, and thus improve the strength and impact resistance of the badminton racket tube;

[0030] 3. Since grinding is not required, the amount of carbon fiber used can be reduced, the production process can be optimized, the production cost of the middle tube of the badminton racket can be saved, and the production efficiency can be improved. Description of the Drawings

[0031] Figure 1 It is a cross-sectional view of the manufacturing equipment for the middle tube of the badminton racket in the present invention.

[0032] Figure 2 It is a schematic structural view of the connection of the lid, the sleeve and the core mold of the autoclave in the present invention.

[0033] Figure 3 It is a cross-sectional view of the sleeve in the present invention.

[0034] Figure 4 It is a cross-sectional view of the lid of the autoclave in the present invention.

[0035] Figure 5 It is a schematic structural view of the core mold and the carbon fiber cloth and the pressure belt wound outside the core mold in the present invention. Detailed Embodiments

[0036] In order to better understand the purpose, structure and function of the present invention, the manufacturing method and manufacturing equipment of the middle tube of the badminton racket in the present invention will be further described in detail below with reference to the drawings.

[0037] As Figures 1 to 5 shown, the manufacturing method of the middle tube of the badminton racket in the present invention includes the following steps:

[0038] 1. Select the core mold 10 according to the specifications and dimensions of the middle tube of the badminton racket to be manufactured.

[0039] 2. Prepare the carbon fiber cloth. According to the specifications, dimensions and performance design requirements of the middle tube to be manufactured, select the appropriate type and angle of carbon fiber cloth and cut it into suitable dimensions.

[0040] 3. Apply a release agent and a carbon fiber cloth adhesive on the surface of the core mold 10. Based on the core mold 10, roll the prepared carbon fiber cloth on the outer surface of the core mold 10 so that the carbon fiber cloth is stacked layer by layer to form a carbon rod structure 11 that completely matches the size and shape of the middle tube standard part.

[0041] 4. Wind the pressure belt 12 on the outer surface of the wound carbon rod structure 11. As Figure 5 shown, the pressure belt 12 starts winding from one end of the carbon rod structure 11 close to the upper part of the core mold 10 and sequentially winds to the end of the carbon rod structure 11 close to the lower part of the core mold 10.

[0042] 5. Seal the end of the carbon rod structure 11 and the pressure belt 12 near the lower part of the core mold 10, so that during the curing process of the carbon rod structure 11, the external environment outside the pressure belt 12 cannot communicate with the carbon rod structure 11 through the lower end parts of the carbon rod structure 11 and the pressure belt 12. Specifically, as Figure 5 shown, when the pressure belt 12 is wound around the lower end part of the carbon rod structure 11, the pressure belt 12 can be continuously wound downward along the core mold 10, so that the pressure belt 12 is hermetically connected to the core mold 10, and the lower end of the carbon rod structure 11 is sealed through the structure of the pressure belt 12 itself; preferably, the pressure belt 12 extends and winds 8 mm - 12 mm from the lower end of the carbon rod structure 11 to the core mold 10 to achieve the optimal sealing effect and not waste too much material of the pressure belt 12.

[0043] Preferably, the pressure belt 12 is made of a material that can shrink when heated, such as OPP material. The pressure belt 12 is in the shape of a slender strip and has a self-adhesive, which is convenient for winding and conducive to achieving a good sealing effect.

[0044] Of course, other methods can also be used to achieve the sealing effect at the lower ends of the carbon rod structure 11 and the pressure belt 12. For example, after the pressure belt 12 is wound around the lower end part of the carbon rod structure 11, a sealing silicone sleeve or a sealing film and other sealing structures are sleeved at the lower end parts of the carbon rod structure 11 and the pressure belt 12, so that the lower ends of the carbon rod structure 11 and the pressure belt 12 are hermetically connected to the core mold 10 to prevent the lower end of the carbon rod structure 11 from communicating with the external environment through the lower end of the pressure belt 12.

[0045] 6. Apply pressure and heat to the carbon rod structure 11 wound with the pressure belt 12 and the core mold 10, so that the carbon fiber cloth and resin constituting the carbon rod structure 11 are cured and formed.

[0046] Specifically, the carbon rod structure 11 wound with the pressure belt 12 and the core mold 10 are placed together into a autoclave, and the autoclave is pressurized and heated. The pressure belt 12 will shrink when heated, and then generate pressure on the carbon rod structure 11 covered inside the pressure belt 12. The carbon fiber cloth and resin constituting the carbon rod structure 11 will be cured under the action of heat and pressure.

[0047] Furthermore, since the autoclave also has a relatively high pressure, a uniform pressure is applied to the outside of the pressure belt 12. On the one hand, the pressure within the autoclave increases the pressure applied to the carbon fiber cloth and resin during the curing process, thereby enhancing the curing effect of the carbon fiber and resin and improving the strength and impact resistance of the badminton racket's center tube. On the other hand, the pressure within the autoclave prevents the outer surface of the carbon rod structure 11 from leaving any entanglement marks caused by the contraction of the pressure belt 12, thereby eliminating the need for subsequent grinding of the center tube. This is because the pressure within the autoclave applies a uniform pressure to the outer surface of the pressure belt 12, making the pressure applied by the pressure belt 12 on the outer surface of the carbon rod structure 11 more stable and uniform, thereby avoiding the problem of entanglement marks caused by local high and local low pressures when the pressure belt 12 contracts. At the same time, since the carbon rod structure 11 within the pressure belt 12 is also subjected to the pressure from the autoclave as a whole, the reaction force of the carbon fiber cloth and resin on the inner surface of the pressure belt 12 is reduced, thus reducing or avoiding the problem of entanglement marks.

[0048] Furthermore, when the carbon rod structure 11 wrapped with the pressure belt 12 is placed into the autoclave together with the core material mold 10, the preferred method is as follows: first, a sleeve 20 with a hollow structure inside is connected to the core material mold 10, and the lower end of the sleeve 20 is sleeved on the outside of the upper end of the core material mold 10 and docked with the upper end of the carbon rod structure 11; then, the sleeve 20 and the carbon rod structure 11 are sealed at the joint by wrapping tape or arranging other sealing devices, so that the core material mold 10 wrapped with the pressure belt 12 and the carbon fiber cloth and the sleeve 20 form a whole; Figure 1 and Figure 2 As shown, a connecting portion 21 is provided at the upper end of the sleeve 20. The connecting portion 21 is a platform extending in the radial direction of the sleeve 20. The sleeve 20 connected with the core material mold 10 and the carbon rod structure 11 is placed into the autoclave from the tank opening of the autoclave. The connecting portion 21 can be just stuck at the tank opening of the autoclave to prevent the sleeve 20 from falling to the bottom of the autoclave. After the sleeve 20 is placed, the autoclave cover 30 can be covered to carry out the heating and pressurizing process.

[0049] Preferably, the connection portion 21 of the sleeve 20 is sealed with the mouth or lid of the autoclave to keep the space between the inner wall of the autoclave and the outer wall of the sleeve sealed, thereby ensuring that the pressure in the autoclave remains balanced and stable. Figure 1As shown, the inner wall of the autoclave lid 30 is provided with a sealing thread, and correspondingly, the outer wall of the autoclave mouth is also provided with a sealing thread. When the lid 30 is added, the lid 30 can be sealed and connected to the mouth of the tank through the sealing thread. Therefore, a preferred embodiment of keeping the space between the inner wall of the tank body and the outer wall of the sleeve is to provide a sealing thread on the side wall of the connecting portion 21. When the core material mold 10 is placed in the autoclave, the connecting portion 21 of the sleeve 20 is first connected to the inner wall of the lid 30 of the autoclave through the sealing thread. Then, by holding the lid 30, the core material mold 10 is placed in the mouth of the autoclave, and then the lid 30 is screwed onto the mouth of the autoclave to form a closed space between the inner wall of the autoclave and the outer wall of the sleeve. When the sealing thread is used to achieve a sealed connection between the sleeve connecting portion and the lid, the connecting portion at the upper end of the sleeve may not be fitted or engaged with the mouth of the autoclave.

[0050] The preferred embodiment of placing the core material mold 10 into the autoclave has the following advantages and beneficial effects:

[0051] (1) Figure 1 and Figure 2 As shown, the outer diameter of the sleeve 20 is the same as the outer diameter of the carbon rod structure 11 wrapped with the pressure belt 12, and the inner diameter of the sleeve 20 is slightly larger than the outer diameter of the core material mold 10. Therefore, when the sleeve 20 is sleeved on the outside of the core material mold 10, docked with the carbon rod structure 11 and sealed, an annular exhaust gap is formed between the inner wall of the sleeve 20 and the outer wall of the core material mold 10. The gas generated by the carbon fiber cloth and the resin during the hot pressing curing process can be discharged through the exhaust gap. And because the lower end of the carbon rod structure 11 and the pressure belt 12 are sealed with the core material mold 10 through the sealing structure, the gas generated during the hot pressing curing process can only be discharged along the exhaust gap at the upper end of the carbon rod structure 11. This makes the exhaust process more stable and controllable, and the pressure on the carbon rod structure 11 is also more stable and controllable, which is conducive to avoiding the formation of winding marks on the surface of the cured carbon rod structure 11.

[0052] (2) Figure 1 and Figure 2As shown, the connecting part 21 at the upper end of the sleeve 20 is clamped at the opening of the autoclave, and a through hole 22 is also provided on the connecting part 21 of the sleeve 20. The through hole 22 is communicated with the hollow structure inside the sleeve 20. The gas generated during the curing process of the carbon rod structure 11 can enter the hollow structure inside the sleeve 20 along the exhaust gap and then be discharged through the through hole 22 at the upper end of the sleeve 20. An exhaust port 31 is provided on the lid 30 of the autoclave, and the exhaust port 31 is correspondingly arranged with the through hole 22 at the upper end of the sleeve 20. After the gas is discharged from the through hole 22, it is then discharged to the outside of the autoclave through the exhaust port 31. Through this exhaust method, it is possible to avoid the gas generated during the curing process from being directly discharged into the heating and pressurizing space of the autoclave, further improving the stability and uniformity of the pressure on the carbon rod structure 11, and avoiding the surface of the cured carbon rod structure 11 from being uneven.

[0053] (3) The connecting part 21 at the upper end of the sleeve 20 also has the advantage of facilitating the gripping of the relatively thin and long core mold 10, making it convenient to put in and take out. Moreover, by selecting the length of the sleeve 20, it is possible to facilitate the control of the placement position of the core mold 10 in the autoclave, so that the core mold 10 extends into the middle part of the autoclave and is fully pressed and heated. In addition, after the core mold 10 is placed in the autoclave, the action of covering the lid 30 of the autoclave can be completed smoothly, simplifying the operation process.

[0054] 7. After the hot pressing and curing molding is completed, release the pressure and temperature in the autoclave to cool the inside of the autoclave. After cooling, take out the sleeve 20, the core mold 10 together with the carbon rod structure 11 and the pressure belt 12 from the autoclave, remove the sleeve 20 and the pressure belt 12, and draw out the core mold 10, then a middle tube blank with a smooth surface can be obtained.

[0055] 8. According to the standard length of the middle tube to be manufactured, cut both ends of the middle tube blank so that the length of the middle tube blank meets the standard, and then the required middle tube finished product can be obtained.

[0056] In the manufacturing method of the badminton racket middle tube described above, the core mold 10 is preferably an iron core mold, and the core mold 10 made of other hard materials can also be used.

[0057] Next, taking the manufacture of a middle tube with specific dimensions as an example, the manufacturing method of the badminton racket middle tube in the present invention will be further described in detail.

[0058] Prepare a badminton racket middle tube with dimensions of an outer diameter of 7.0 mm, an inner diameter of 4.0 mm, and a length of 300 mm:

[0059] Step 1, take out an iron core mold with an outer diameter of 4.0 mm and a length of 500 mm.

[0060] Step 2: Cut the carbon fiber cloth, including two pieces of carbon fiber cloth with a size of 7.2*330mm and an angle of 45°, and one piece of carbon fiber cloth with a size of 6.6*330mm and an angle of 0°.

[0061] Step three: Apply mold release agent and carbon fiber cloth adhesive on the outer surface of the core mold, cross-stick two pieces of 45° carbon fiber cloth and roll them on the core mold, and then roll a piece of 0° carbon fiber cloth to form a carbon rod structure with an outer diameter of 7.0 mm.

[0062] Step 4: Roll an OPP tape with self-adhesive glue on the outside of the carbon rod structure, and roll it along the iron core mold from top to bottom. After winding 5-10 turns, it can be rolled to the lower end of the carbon rod structure, and then continue to wind it downward so that the OPP tape is wrapped around the iron core mold at the bottom of the carbon rod structure, so that the part wrapped with the OPP tape continues to extend downward along the lower end of the carbon rod structure for about 10 mm to achieve the effect of sealing the lower end of the carbon rod structure.

[0063] Step 5: Select a sleeve with an outer diameter of 8.0 mm, an inner diameter of 4.5 mm, and a length of 200 mm, and place the sleeve on the outside of the upper end of the core mold so that the lower end of the sleeve is connected to the upper end of the carbon rod structure, and wrap sealing tape around the outside of the joint where the sleeve and the carbon rod structure are connected to each other so that the sleeve and the carbon rod structure are sealed and connected as a whole.

[0064] Step 6: Screw the upper connection of the sleeve onto the autoclave lid until it is sealed against the inner wall of the lid. Then, holding the lid, place the lower end of the sleeve, along with the core mold, into the autoclave along the opening. Screw the lid until the lid is sealed to the opening via the sealing threads. Preferably, the upper end of the sleeve should extend approximately 20 mm beyond the opening to facilitate the removal of gases generated by the curing of the carbon fiber cloth and resin.

[0065] Step 7: Heat the autoclave to 150°C and pressurize to 3 kgf / cm 2 , lasting for 1.5 hours, to allow the carbon rod structure to solidify and form.

[0066] Step eight, open the air pressure valve of the autoclave to cool the autoclave, take out the sleeve and core mold, remove the sleeve and OPP belt, and pull out the core to obtain a rough middle tube with a smooth surface; then cut 15mm at each end of the rough middle tube to obtain a finished middle tube with standard size specifications, completing the production.

[0067] The present invention also discloses a manufacturing device for the badminton racket middle tube manufacturing method, which will be described in further detail below with reference to the accompanying drawings.

[0068] like Figure 1As shown, the manufacturing equipment for the badminton racket middle tube of the present invention includes an autoclave, which includes a tank body 40 and a tank cover 30. The tank body 40 is an elongated cylinder with a hollow storage chamber formed therein. The upper end of the tank body 40 is provided with a tank opening. The tank cover 30 is located on the tank opening of the tank body 40 to seal the storage chamber within the tank body 40. The lower end of the tank body 40 is provided with an air inlet valve 41 for opening or closing the air inlet passage of the autoclave to control the pressurization level within the autoclave. A heating assembly 42 is provided around the inner wall of the tank body 40. The heating assembly 42 preferably extends from the upper portion of the tank body 40 to the lower portion of the tank body 40 to uniformly heat the storage chamber within the tank body 40.

[0069] Furthermore, the manufacturing equipment of the badminton racket middle tube of the present invention further includes a sleeve 20 and a core material mold 10. Figure 5 As shown, the core mold 10 is a slender rod-shaped structure used to roll the carbon fiber cloth and pressure belt 12 required for preparing the middle tube of the badminton racket to shape the carbon fiber cloth; a T-shaped fixing portion 13 is formed at one end of the core mold 10 to facilitate holding or fixing the core mold 10, making it convenient to move the mold or facilitate rolling operations. Figures 1 to 3 As shown, the sleeve 20 is a slender tubular structure with a hollow interior. The lower end of the sleeve 20 is an opening. The sleeve 20 can be installed on the outside of the core material mold 10 through the opening, so that the end where the T-shaped fixing part 13 of the core material mold 10 is located extends into the interior of the sleeve 20.

[0070] like Figure 2 As shown, the carbon fiber cloth and the pressure belt 12 are rolled on the outside of the core mold 10, and a carbon rod structure 11 is formed on the outer surface of the core mold 10. When the sleeve 20 is sleeved on the outside of the core mold 10, the end where the opening of the sleeve 20 is located is connected to the end of the carbon rod structure 11 on the outer surface of the core mold 10, and the joint between the sleeve 20 and the carbon rod structure 11 is sealed by a sealing structure such as a sealing tape or a sealing ring, and the sleeve 20 and the core mold 10 form a whole.

[0071] The outer diameter of the sleeve 20 is the same as the outer diameter of the carbon rod structure 11 wrapped with the pressure belt 12, and the inner diameter of the sleeve 20 is slightly larger than the outer diameter of the core mold 10. Therefore, when the sleeve 20 is sleeved on the outside of the core mold 10, docked with the carbon rod structure 11 and sealed, an annular exhaust gap is formed between the inner wall of the sleeve 20 and the outer wall of the core mold 10. The gas generated by the carbon fiber cloth and resin during the hot pressing and curing process can be discharged through the exhaust gap.

[0072] Further, if Figure 1 and Figure 2As shown, a connecting portion 21 is further provided at the upper end of the sleeve 20 away from the core mold 10. The connecting portion 21 is a platform extending in the radial direction of the sleeve 20. When the sleeve 20 connected with the core mold 10 and the carbon rod structure 11 is placed into the autoclave from the mouth of the autoclave, the connecting portion 21 can be exactly clamped at the mouth of the autoclave to prevent the sleeve 20 from falling to the bottom of the autoclave. The connecting portion 21 is preferably a platform structure with a shape matching that of the mouth of the autoclave, so as to be completely clamped on the mouth of the autoclave and seal the mouth of the autoclave. A through hole 22 is also provided on the connecting portion 21 of the sleeve 20. The through hole 22 is communicated with the hollow structure inside the sleeve 20. The gas generated during the curing process of the carbon rod structure 11 can enter the hollow structure inside the sleeve 20 along the exhaust gap and then be discharged through the through hole 22 at the upper end of the sleeve 20. As Figure 1 and Figure 4 shown, an exhaust port 31 is provided on the lid 30 of the autoclave. The exhaust port 31 is correspondingly arranged with the through hole 22 at the upper end of the sleeve 20. After the gas is discharged from the through hole 22, it is then discharged to the outside of the autoclave through the exhaust port 31, so as to prevent the gas generated during the curing process from being directly discharged into the heating and pressurizing space of the autoclave, further improving the stability and uniformity of the pressure on the carbon rod structure 11 and making the surface of the cured carbon rod structure 11 flat and smooth.

[0073] In addition, the connecting portion 21 at the upper end of the sleeve 20 also has the advantage of facilitating the gripping of the relatively thin and long core mold 10, making it convenient to put in and take out. Moreover, by selecting the length of the sleeve 20, it is convenient to control the placement position of the core mold 10 in the autoclave, so as to extend the core mold 10 to the position where the heating component 42 is located in the autoclave, enabling the carbon rod structure 11 to be heated evenly and sufficiently.

[0074] Furthermore, as Figure 1 and Figure 4 shown, sealing threads are provided on the outer wall of the mouth of the autoclave. Correspondingly, sealing threads are provided on the inner wall of the lid 30. By screwing the lid 30, the lid 30 can be hermetically connected with the sealing threads at the mouth of the autoclave. Of course, sealing structures such as sealing rubber strips and sealing buckles can also be used to achieve the sealing connection between the lid 30 and the mouth of the autoclave.

[0075] Preferably, the connecting portion 21 of the sleeve 20 is hermetically connected with the mouth of the autoclave or the lid, so as to keep the space between the inner wall of the autoclave body and the outer wall of the sleeve in a sealed state, thereby ensuring that the pressure inside the autoclave maintains a balanced and stable state. Specifically, as Figure 1As shown, a sealing thread can be provided on the side wall of the connecting portion 21. When the core material mold 10 is placed in the autoclave, the connecting portion 21 of the sleeve 20 is first connected to the inner wall of the autoclave cover 30 through the sealing thread. After that, the core material mold 10 is placed into the mouth of the autoclave by holding the cover 30, and then the cover 30 is screwed onto the mouth of the autoclave. Of course, other methods can also be used to keep the space between the inner wall of the autoclave body and the outer wall of the sleeve sealed. For example, a sealing ring, a sealing strip or a sealing buckle can be provided on the lower surface of the sleeve connecting portion 21 and / or the upper surface of the autoclave mouth, so that the connecting portion 21 is sealed with the mouth of the autoclave when it is fitted or clamped at the mouth of the autoclave.

[0076] When manufacturing a badminton racket middle tube using the badminton racket middle tube manufacturing equipment of the present invention, first, the cut carbon fiber cloth is rolled onto the outside of the core material mold 10 by a sticky material such as resin to form a carbon rod structure 11;

[0077] Then, a pressure belt 12 is wound around the outer surface of the rolled carbon rod structure 11, starting from the upper end of the carbon rod structure 11 and winding to the lower end of the carbon rod structure 11, and the pressure belt 12 is continued to be wound downward along the core material mold 10, so that the pressure belt 12 and the core material mold 10 are sealed and connected to each other, thereby preventing the carbon rod structure 11 from communicating with the external environment outside the pressure belt 12 through the lower end of the carbon rod structure 11 during the curing process;

[0078] Then, the sleeve 20 is placed on the core material mold 10 so that the sleeve 20 is in contact with the upper end of the carbon rod structure 11 that has not been sealed, and the joint between the two is sealed;

[0079] Then, the sleeve 20 is placed into the autoclave through the opening of the autoclave, so that the connecting portion 21 of the sleeve 20 is locked in the opening of the autoclave, and the cover 30 is screwed on the opening of the autoclave to seal the opening of the autoclave.

[0080] Open the air inlet valve 41 to allow gas to enter the autoclave to pressurize the autoclave, and simultaneously turn on the heating assembly 42 to heat the autoclave, so that the carbon rod structure 11 in the autoclave is solidified and formed under heat and pressure;

[0081] After hot pressing and curing, the pressure in the autoclave is removed, and the heating assembly 42 is turned off to cool the autoclave and release the pressure. Then, the sleeve 20 and the core mold 10 are removed, the sleeve 20 and the pressure belt 12 are removed, and the core mold 10 is pulled out to obtain a badminton racket middle tube with a smooth outer surface.

[0082] The badminton racket middle tube manufacturing method and manufacturing equipment of the present invention have the following advantages:

[0083] 1. It enables the middle tube of the badminton racket not to require a grinding process during production, ensuring the continuity of the carbon fiber inside the middle tube and the integrity of the resin protective layer on the surface of the middle tube, guaranteeing the full play of the excellent performance of the carbon fiber and enhancing the conduction ability of the middle tube.

[0084] 2. It can increase the forming pressure of the middle tube of the badminton racket, strengthen the curing effect of the carbon fiber and the resin, and thus enhance the strength and impact resistance of the middle tube of the badminton racket.

[0085] 3. Since there is no need for grinding, it can reduce the usage amount of carbon fiber, optimize the production process, save the production cost of the middle tube of the badminton racket, and improve the production efficiency.

[0086] The above further describes the present invention with the aid of specific embodiments. However, it should be understood that this specific description should not be construed as a limitation on the essence and scope of the present invention. Various modifications made by those of ordinary skill in the art to the above embodiments after reading this specification all fall within the scope protected by the present invention.

Claims

1. A manufacturing method of a middle tube of a badminton racket, characterized in that, The steps include: Prepare a core mold. Wind the carbon fiber cloth around the core mold to form a carbon rod structure. Wind a pressure belt around the carbon rod structure. After winding the pressure belt around the carbon rod structure, seal the first end of the carbon rod structure, so that the pressure belt near the first end of the carbon rod structure is hermetically connected to the core mold. Connect a sleeve on the core mold, the sleeve is fixedly connected to the core mold, the sleeve is sleeved outside the core mold, and is butt-jointed with the second end of the carbon rod structure. Seal the joint between the sleeve and the second end of the carbon rod structure. The inner diameter of the sleeve is larger than the outer diameter of the core mold. When the sleeve is sleeved outside the core mold, an exhaust gap is formed between the inner wall of the sleeve and the outer wall of the core mold. Put the carbon rod structure wound with the pressure belt and the core mold together into a pressure heating device through the sleeve for pressure heating, so that the carbon rod structure is cured and formed. Remove the pressure belt outside the carbon rod structure and extract the core mold from the carbon rod structure.

2. The manufacturing method of the middle tube of the badminton racket according to claim 1, characterized in that, When winding the pressure belt, the pressure belt starts from the second end of the carbon rod structure and is sequentially wound to the first end of the carbon rod structure, and continues to wind the pressure belt onto the core mold near the first end of the carbon rod structure, so that the pressure belt is hermetically connected to the core mold.

3. The manufacturing method of the middle tube of the badminton racket according to claim 2, characterized in that, The pressure belt extends and winds 8 mm - 12 mm from the first end of the carbon rod structure to the core mold.

4. The manufacturing method of the middle tube of the badminton racket according to claim 1, characterized in that, After one end of the sleeve is fixedly connected to the core mold, the other end of the sleeve is hermetically connected to the inner wall of the pressure heating device, so that a closed space is formed between the inner wall of the pressure heating device and the outer wall of the sleeve.

5. The manufacturing method of the middle tube of the badminton racket according to claim 1, characterized in that, Wind a sealing tape at the joint between the sleeve and the second end of the carbon rod structure to seal the joint part, and connect the sleeve and the core mold into a whole.

6. The manufacturing method of the middle tube of the badminton racket according to claim 1, characterized in that, The outer diameter of the carbon rod structure formed by winding is the same as the outer diameter dimension of the middle tube standard part to be manufactured.

7. A manufacturing device for the middle tube of a badminton racket, characterized in that, Applied to the manufacturing method of the badminton racket according to any one of claims 1 to 6, including a core mold, a hot pressing device and a sleeve. The core mold is a slender rod-shaped structure. The material for manufacturing the middle tube is wound on the core mold. A containing chamber is formed inside the hot pressing device. The inside of the sleeve is hollow. The first end of the sleeve is an opening, and the opening is sleeved outside the core mold, is butt-jointed with the material for manufacturing the middle tube wound on the core mold, and is connected to the core mold. The inner diameter of the sleeve is larger than the outer diameter of the core mold. An exhaust gap is formed between the inner wall of the sleeve and the outer wall of the core mold. The core mold is placed in the containing chamber of the hot pressing device through the sleeve, and the material for manufacturing the middle tube is cured and formed under the environment of heating and pressurization.

8. The manufacturing equipment for the middle tube of a badminton racket according to claim 7, characterized in that, The hot pressing device includes a tank body and a tank cover. One end of the tank body is provided with a tank opening, and the tank cover covers the tank opening of the tank body. An air inlet valve is provided on the tank body, and the air inlet valve can open or close the air inlet channel of the hot pressing device to control the pressure value in the containing chamber. A heating component is provided inside the tank body, and the heating component can heat the containing chamber.

9. The manufacturing equipment for the middle tube of a badminton racket according to claim 7 or 8, characterized in that, The second end of the sleeve is provided with a connecting part, and the connecting part can be clamped on the tank opening of the hot pressing device.

10. The manufacturing equipment for the middle tube of a badminton racket according to claim 9, characterized in that, A through hole is provided on the connecting part of the sleeve, and the through hole is communicated with the hollow structure inside the sleeve. An exhaust port is provided on the tank cover of the hot pressing device, and the exhaust port is correspondingly arranged with the through hole on the connecting part of the sleeve.

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