Carbon fiber badminton racket and manufacturing method thereof

Abstract

The invention discloses a carbon fiber badminton racket and a manufacturing method thereof, and relates to a carbon fiber badminton racket and a manufacturing method thereof. The racket rod is connected with the racket frame, the joint is used for fixedly connecting the racket frame and the racket rod, the rear end of the racket rod is fixedly connected with a racket handle, the front end of the racket handle is provided with a conical front sleeve, the surface of the racket handle is wound with an anti-skid handle skin, and racket threads penetrate through the racket frame through thread protecting nails to form a racket net. The racket rod is of a solid or hollow structure; when the racket rod is of the hollow structure, the inner diameter of the racket rod is uniform; no matter the racket rod is of a solid or hollow structure, the outer diameter of the racket rod is gradually increased in a step shape, the end close to the racket frame is a smaller end, and the end close to the racket handle is a larger end. A rear sleeve is arranged at the rear end of the racket handle. The racket rod is formed by wrapping 2-6 cylinders with different lengths and outer diameters layer by layer, so that the racket rod with 1-5 steps is formed.

Description

Technical Field

[0001] A carbon fiber badminton racket and a manufacturing method thereof according to the present invention relate to a carbon fiber badminton racket and a method for manufacturing the badminton racket. Background Art

[0002] Badminton is a widely developed national sports activity. For users, it is very important to use a good and easy-to-use badminton racket during the sport. If a bad racket is used, it will have a great impact on the user's playing style and mood, and may even cause sports injuries to the user, which is more prominent in some competitive games. Therefore, users will choose badminton rackets with different playing style characteristics according to their own characteristics: users with an offensive playing style hope to choose a badminton racket with sufficient offensive power, users with a speed playing style hope to choose a badminton racket with a fast swing speed and a fast rebound speed of the racket, and users with a balanced (all-round) playing style hope to choose a badminton racket with balanced and all-round performance such as swing speed, racket rebound and offensive power. At present, the design and manufacture of badminton rackets are being segmented according to the playing style characteristics of users to design and manufacture good and easy-to-use badminton rackets with different characteristics to meet the needs of users and badminton sports.

[0003] For existing badminton rackets, their racket shafts usually adopt hollow cylinders with equal diameters. During design and manufacture, the hollow cylinders use the same material combination in the length direction, and the wall thickness of the hollow cylinders is generally uniform. They are manufactured using a one-time forming process. Therefore, the performance such as rigidity and elasticity of the racket shaft in the length direction is also uniform. However, during actual use, due to the different usage requirements of different style players, in order to achieve excellent hitting quality, it is required that the performance such as rigidity and elasticity of the racket shaft in the length direction cannot be completely uniform, and the maximum deformation position cannot be in the middle of the racket shaft.

[0004] For existing badminton rackets, during the hitting process, the maximum deformation position of the racket shaft after hitting the ball is in the middle of the racket shaft. Under the same hitting conditions: (1)For players with an attacking style, during the attacking process, the quality of the ball hit mainly lies in the skills and ability of active exertion. At the same time, making full use of the inertial energy and rebound energy of the racket will further increase the power of the attack. Therefore, for current attacking-style rackets, the middle rod has a tendency to become softer. A softer racket rod will have a larger deformation after hitting the ball, and the racket rod can generate more elastic energy. For current rackets, since the maximum deformation point of the racket rod is in the middle of the racket rod, the distance from the hitting point on the racket face to the maximum deformation point of the racket rod is fixed. The rigidity of the racket rod is uniform in the length direction. Therefore, a softer racket rod causes a larger swing of the racket face. For attacking shots, the swing of the racket face will cause the hitting angle of the badminton (relative to the court plane) to become larger when the racket hits the ball, the flying distance of the badminton to become farther, and the landing speed of the badminton to become slower, resulting in insufficient power. Moreover, the longer recovery time of the racket with a larger swing will lead to a decrease in the continuous hitting stability of the racket and a decrease in the quality of continuous hitting.

[0005] For rackets with an attacking style, when players use them, there may also be situations of passive defense. Since the middle rod of attacking-style rackets is softer and the swing weight is larger, in the case of receiving the ball without active exertion, there will be a situation of "energy leakage". The reason for the "energy leakage" is that the rebound speed is slow due to the soft racket rod. After the energy of the ball is absorbed by the racket (racket rod), there is no borrowing of the rebound energy of the racket (racket rod), resulting in the hit ball having no speed and power. Therefore, how to balance the possible defensive ball receiving of attacking-style rackets has also become a current research topic. In fact, the situation of "energy leakage" can be solved by reducing the swing weight of the racket and increasing the hardness of the racket rod. However, reducing the swing weight of the racket will reduce the inertial energy of the racket and the downward pressure of the racket head during the attack. Increasing the hardness of the racket rod will require players to have higher strength and exertion skills. At the same time, increasing the hardness of the racket rod is also likely to cause sports fatigue and even sports injuries to players. Therefore, how to improve the defensive performance of attacking-style rackets has become an urgent problem to be solved for current attacking-style rackets.

[0006] (2)For players with a speed-oriented style, the quality of the ball hit will rely more on the swing speed of the racket and the rapid rebound energy. Therefore, for current speed-oriented rackets, the racket rod has a tendency to become harder. For a harder racket rod, the deformation of the racket rod after hitting the racket face is smaller, and the swing of the racket face is also smaller. Therefore, the recovery time of the racket after hitting the ball is faster, and the hitting speed of the ball when hitting is faster. For current rackets, since the maximum deformation point of the racket rod is in the middle of the racket rod, the distance from the hitting point on the racket face to the maximum deformation point of the racket rod is fixed. However, due to the harder rigidity of the racket rod, the deformation of the racket rod during hitting is smaller, and the elastic energy generated by the racket rod is smaller, which will result in less energy borrowed by the badminton when the racket hits the ball, thus leading to insufficient speed and power of the ball after it is hit out of the racket face. Moreover, a harder racket rod will cause sports fatigue and sports injuries to the user.

[0007] For a racket with the characteristics of a partial speed type, it is possible for the player to actively exert force during use. Since the middle rod of the racket with the characteristics of a partial speed type is relatively hard, the swing speed is relatively fast, and the swing weight is relatively low, when actively exerting force to attack, the speed of the racket is relatively fast but the inertial energy is insufficient, resulting in insufficient power and downward pressure when hitting the ball. The reason for the "insufficient power and downward pressure" is the insufficient deformation of the racket (racket rod) when hitting the ball and the insufficient inertial energy, which causes insufficient elastic energy of the racket rod and insufficient downward pressure of the racket head. Therefore, how to balance the possible active force for attacking in a racket with the characteristics of a partial speed type has become a current research topic. In fact, the situation of "insufficient power and downward pressure" can be achieved by increasing the swing weight of the racket and reducing the hardness of the racket rod. However, increasing the swing weight of the racket and reducing the hardness of the racket rod will also reduce the rebound speed of the racket. How to balance the two has become an urgent problem for the current racket with the characteristics of a partial speed type. Therefore, it is necessary to design a new badminton racket to meet the actual needs, especially the needs of competitive players. Summary of the Invention

[0008] The technical problem to be solved by the present invention is: to overcome the problems existing in the prior art and provide a carbon fiber badminton racket and its manufacturing method. By using the badminton racket designed and manufactured by the present invention, the swing amplitude and cycle length of the racket face after hitting the ball can be set. By setting the rigidity, elasticity, and torsional resistance at corresponding positions in the front and back directions of the racket rod in the length direction, the bending (elastic) position of the racket rod can be adjusted, the length of the swing arm of the racket face after hitting the ball can be reduced, the swing cycle of the racket face after hitting the ball can be shortened, the reset speed of the racket face after hitting the ball can be increased, the recovery speed, hitting force, and hitting angle of different characteristic rackets can be adjusted, the downward pressure, stability, and continuous hitting ability of the racket can be improved, and the vibration of the racket can be reduced, and finally a high-performance badminton racket suitable for different playing characteristics can be obtained.

[0009] The technical solution for the present invention to solve its technical problems is as follows: A carbon fiber badminton racket has: An annular racket frame, a racket rod connected to the racket frame, and a joint for fixedly connecting the racket frame and the racket rod. The rear end of the racket rod is fixedly connected with a racket handle. The front end of the racket handle has a conical front sleeve. The surface of the racket handle is wound with a grip for anti-slip. The racket frame is threaded with strings through string protectors to form a racket net.

[0010] The racket rod is of a solid or hollow structure; when it is of a hollow structure, the inner diameter of the racket rod is uniform; whether the racket rod is of a solid or hollow structure, the outer diameter of the racket rod gradually increases in a stepped shape, with the end close to the racket frame being the smaller end and the end close to the racket handle being the larger end.

[0011] The rear end of the racket handle has a rear sleeve.

[0012] The further improved technical solution of the present invention is as follows: Preferably, the racket rod is formed by wrapping 2 to 6 cylinders with different lengths and outer diameters layer by layer, so as to form a racket rod with 1 to 5 levels of steps.

[0013] The outer diameter dimension of the smallest end of the racket rod is between φ5.5mm and φ6.5mm, and the outer diameter dimension of the largest end is between φ6.2mm and φ7.2mm; the difference between the outer diameter of the largest end and the outer diameter of the smallest end of the racket rod is between 0.20 and 1.20mm, and the difference in outer diameter between adjacent two levels of steps is between 0.10 and 0.30mm.

[0014] Preferably, the length of the segmented part at the smallest end of the racket rod is 80 to 200mm, and the length of the segmented part at the largest end is 120 to 240mm; when the number of steps is greater than 3 levels, the length of the adjacent stepped transition section is 5 to 60mm.

[0015] The elasticity of the part with the smallest outer diameter of the racket rod is better than that of the part with the largest outer diameter; the rigidity of the part with the largest outer diameter of the racket rod is harder than that of the part with the smallest outer diameter; the resistance to torsional deformation of the part with the largest outer diameter of the racket rod is smaller than that of the part with the smallest outer diameter.

[0016] One end of the part with the smallest outer diameter of the racket rod is used as the front end of the racket rod to be connected with the racket frame, and one end of the part with the largest outer diameter is used as the rear end of the racket rod to be connected with the front sleeve and the racket handle.

[0017] Preferably, when the racket rod is in a hollow structure, the inner diameter dimension of the hollow part is not greater than φ5.0mm, the length is 280 to 320mm, and the racket rod is made of carbon fiber composite material.

[0018] Preferably, when the racket rod is in a solid structure, the racket rod is manufactured by a three-time molding process, and from the inside to the outside, it is successively a solid cylinder one, a solid cylinder two and a stepped layer. The solid cylinder one is composed of a cylinder made of carbon fiber material and a polymer material filled inside; the diameter of the polymer material filled inside the solid cylinder one is φ0.6 - φ1.2mm, and the diameter of the solid cylinder one is φ2.20mm - φ2.80mm.

[0019] Preferably, when the racket rod is in a hollow structure (inner diameter ≤ φ5.0mm), the racket rod is manufactured by a two-time molding process, including a hollow cylinder and a stepped layer.

[0020] Specifically, the polymer material filled inside is a shock-absorbing material, specifically a reinforced fiber resin.

[0021] Preferably, when the racket rod is in a solid structure, a manufacturing method of a carbon fiber badminton racket of the present invention is realized by the following steps: S1. Racket rod manufacturing; S1.1. Winding of the solid cylinder one S1.2. Rolling of the solid cylinder II S1.3. Step layer rolling S2. Manufacturing of the racket frame strip S3. Pre-forming of the racket frame S4. Blank forming S5. Drilling and grinding of the racket frame S6. Assembling the front sleeve and the racket handle S7. Painting and beautifying processing of the racket frame, racket shaft and front sleeve S8. Manufacturing the racket

[0022] When the racket shaft is of solid structure, the specific method for manufacturing a carbon fiber badminton racket of the present invention is implemented by the following steps: S1. Racket shaft manufacturing: The racket shaft sequentially includes a step layer, a solid cylinder II, and a solid cylinder I from outside to inside. The solid cylinder II and the solid cylinder I are tightly combined. The step layer is composed of a maximum outer diameter layer, a transition layer, and a minimum outer diameter layer. The maximum outer diameter layer and the transition layer are tightly joined on the solid cylinder II; S1.1. Rolling of the solid cylinder I (11) According to the size requirements of the solid cylinder I, take a carbon fiber composite prepreg containing epoxy resin that meets the size thickness of the solid cylinder, and cut it into a specified size according to the requirements. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (12) Take a high-temperature resistant polymer material wire with a diameter of φ0.6 - φ1.2 mm and a length of 450 - 550 mm. Place the cut carbon fiber composite prepreg on the workbench, place the polymer material wire on the carbon fiber composite prepreg, and at the same time, align the edge of the prepreg with the polymer material wire in a straight line and stick them tightly, and then roll it into a solid cylinder shape by one turn; (13) Put the above-mentioned rolled solid cylinder into a special molding die and fix the die.

[0023] (14) Put the die into a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes; (15) Remove the die from the heating device and place it in a cooling device for cooling. The cooling temperature is 5 - 15 °C, and the cooling time is 5 - 10 minutes. Wait until the die cools to 45 - 55 °C, open the die, and take out the formed solid cylinder I blank; (16) Grind the above-mentioned solid cylinder I blank to the specified size of φ2.20 mm - φ2.80 mm, that is, the solid cylinder I is made.

[0024] S1.2. Rolling of the solid cylinder II (21)According to the dimensional requirements of the solid cylinder II, take the carbon fiber composite prepreg containing epoxy resin that meets the thickness of the solid cylinder II, cut it into the specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (22)Place the cut carbon fiber composite prepreg on the workbench, place the solid cylinder I on top of the carbon fiber composite prepreg. At the same time, align the edge of the prepreg with the straight line of the solid cylinder I and press it tightly, then roll it around to form a solid cylinder shape; (23)Wrap a special resin cloth on the outer layer of the above-mentioned rolled solid cylinder shape. When rolling, it must be aligned and pressed tightly before proceeding; (24)Use a winding device to tightly wind an OPP film on the outer layer of the above-mentioned rolled solid cylinder; (25)Put the solid cylinder part wound with the OPP film into a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes; (26)After the baked solid cylinder part is cooled, remove the outer OPP film, which is the blank of the solid cylinder II; (27)Grind the above-mentioned blank of the solid cylinder II to the specified size of φ5.50mm - φ6.50mm. The remaining special resin cloth on the outer layer of the ground solid cylinder shape shall not exceed 10% of the original resin cloth volume, that is, the solid cylinder II is made; S1.3. Step layer rolling (31)According to the dimensional requirements of the step layer, take the carbon fiber composite prepreg containing epoxy resin that meets the thickness of the step size, cut it into the specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (32)Place the cut carbon fiber composite prepreg on the workbench, place the solid cylinder II as the core on top of the carbon fiber composite prepreg, align the corresponding step surfaces of the step layer, and at the same time align the edge of the prepreg with the straight line of the solid cylinder II and press it tightly, then roll it around to form a stepped cylinder shape; (33)Wrap a special resin cloth on the outermost diameter layer of the above-mentioned rolled stepped cylinder shape. When rolling, it must be aligned and pressed tightly before proceeding; (34)Use a winding device to tightly wind an OPP film on the outer layer of the above-mentioned rolled stepped cylinder shape; (35)Put the solid stepped cylinder part wound with the OPP film into a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes; (36)After the baked solid stepped cylinder part is cooled, remove the outer OPP film, which is the blank of the racket handle; (37)Grind the maximum outer diameter of the above solid stepped racket shaft to the specified size of φ6.2mm - φ7.2mm. At the same time, grind the stepped transition layer as required. The remaining special resin cloth on the outer layer of the ground tubular part shall not exceed 10% of the original resin cloth volume. After cutting both ends of the ground tubular or solid cylindrical part to the specified length of 280mm - 320mm according to the size requirements of the steps, the badminton racket shaft is made. S2. Manufacturing the racket frame strip S2.1. Cut the lightweight non-woven fiber cloth evenly coated with a foaming resin layer on one side into the specified size as required. Its width is determined according to the average perimeter of the racket frame cross-section, with a width of 5 - 15mm, and its length is determined according to the racket frame perimeter, with a length less than 780mm. S2.2. Cut the carbon fiber composite material prepreg containing epoxy resin into the specified size as required. Its length is determined according to the racket frame perimeter, with a length less than 780mm, and its width is controlled by weight. The weight of the carbon fiber composite material prepreg is controlled within 35 grams. By weight percentage, the weight ratio of epoxy resin in the carbon fiber composite material prepreg is 30% - 45%. S2.3. Place the cut carbon fiber composite material prepreg on the workbench, align one side of the prepreg with the marked straight line on the workbench, then place the cut lightweight non-woven fiber cloth coated with foaming resin on top of the carbon fiber composite material prepreg, with the foaming resin layer of the lightweight non-woven fiber cloth facing up, and then roll it into a tube to obtain a carbon fiber composite material prepreg tubular part with foaming resin in the inner cavity. S3. Pre-forming the racket frame S3.1. Pre-form the rolled carbon fiber composite material prepreg tubular part on the pre-forming mold to obtain a pre-formed racket frame. The pre-forming mold is used to control the racket frame perimeter. Insert joints at both ports of the pre-formed racket frame, and then connect the joints to the upper end of the racket shaft. Paste a carbon fiber composite material prepreg connection patch at the tee joint where the pre-formed racket frame is joined to the upper end of the racket shaft to position and fix the joints, racket frame, and upper end of the racket shaft, obtaining a well-positioned racket pre-form. S3.2. Remove the well-positioned racket pre-form from the pre-forming mold. According to the requirements, paste another carbon fiber composite material prepreg connection patch at the joint where the pre-formed racket frame is joined to the racket shaft and the joints to obtain a carbon fiber badminton racket pre-form. S4. Blank forming S4.1. Place the pre-formed carbon fiber badminton racket pre-form into the racket forming mold, close and fasten the mold, and then move the mold into the heating device for heating. The heating temperature is 145 - 155°C, and the time is 30 - 60 minutes. The carbon fiber badminton racket pre-form cures and forms during the heating process. During the heating of the mold, the foaming resin in the inner cavity of the racket frame of the badminton racket pre-form continuously expands, forming 5kg / cm2 ~12 kg / cm 2 Pressurize it to, and shape the racket frame along the inner cavity of the mold to form the racket frame shape; S4.2. After the racket forming mold reaches the heating time, remove the racket forming mold from the heating device, place it in the cooling device for cooling. The cooling temperature is 5 - 15 °C, and the cooling time is 5 - 10 minutes. After the mold cools to 45 - 55 °C, move the racket forming mold to the workbench, open the mold, and take out the formed carbon fiber composite badminton racket blank; S5. Drilling and grinding the racket frame S5.1. After forming the badminton racket blank, drill holes in the racket frame of the badminton racket blank; S5.2. Fill the slight unevenness on the outer surface of the racket frame with EP series putty, then place it in an oven at 75 - 80 °C and bake for 2 - 3 hours. After the EP series putty is completely cured, use sandpaper to polish the surface of the racket blank flat; S6. Assembling the front sleeve and the racket handle S6.1. Apply 0.5 ± 0.1 g of two-component adhesive to the lower end of the racket shaft of the badminton racket blank. At the same time, apply 0.5 - 1.0 g of two-component adhesive to the joint hole between the racket handle and the racket shaft and on the joint surface between the front sleeve and the racket handle, and connect the front sleeve, the racket handle and the blank racket shaft together; S6.2. Cure the two-component adhesive at room temperature for 12 - 24 hours to firmly bond the front sleeve, the racket handle and the blank racket shaft; S6.3. After firmly bonding, fix the countersunk screw at the joint of the front end of the racket handle and the rear end of the racket shaft to fixedly connect the racket handle and the racket shaft. The head of the countersunk screw is flush with the surface of the racket handle; S7. Painting and beautifying processing of the racket frame, racket shaft and front sleeve After the front sleeve, the racket handle and the blank racket shaft are joined, according to the design requirements, perform painting and beautifying processing on the racket frame, racket shaft and front sleeve, spray various colors of paint and transfer various shaped transfer patterns on the racket frame, racket shaft and front sleeve; S8. Making the racket After the painting and beautifying processing of the racket frame, racket shaft and front sleeve, insert the grommet into the holes of the racket frame, assemble the rear sleeve at the rear end of the racket handle, wrap the grip tape on the outer surface of the racket handle, and then thread the strings through the racket frame according to the stringing method and tighten the strings on the badminton racket stringing machine according to the required tension to make a badminton racket with excellent performance and beautiful appearance.

[0025] When the racket shaft is a hollow structure (inner diameter ≤ φ5.0 mm), the manufacturing method of the present invention is realized by the following steps: S1. Manufacturing the racket shaft; S1.1. Solid cylinder - rolling S1.2. Rolling of the solid cylinder II S1.3. Rolling of the stepped layer S2. Manufacturing of the racket frame strip S3. Pre-forming of the racket frame S4. Blank forming S5. Drilling and grinding of the racket frame S6. Assembling the front sleeve and the racket handle S7. Painting and beautifying processing of the racket frame, racket rod and front sleeve S8. Manufacturing the racket

[0026] When the racket rod is of a hollow structure (inner diameter ≤ φ5.0 mm), the specific manufacturing method of the present invention is realized by the following steps: S1. Manufacturing of the racket rod The racket rod sequentially includes a stepped layer and a hollow cylinder from outside to inside. The stepped layer is composed of a maximum outer diameter layer, a transition layer and a minimum outer diameter layer, and the maximum outer diameter layer and the transition layer are tightly joined to the hollow cylinder; S1.1. Rolling of the hollow cylinder (11) According to the size requirements of the hollow cylinder, take a carbon fiber composite prepreg containing epoxy resin with a thickness meeting the size of the hollow cylinder, and cut it into a specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (12) Place the cut carbon fiber composite prepreg on the workbench, place the core on the carbon fiber composite prepreg, and at the same time align and tightly attach the edge of the prepreg with the marked straight line of the core and then roll it into a tubular cylinder shape; (13) Roll a special resin cloth on the outer layer of the above-mentioned rolled tubular cylinder shape, and it must be aligned and tightly attached during rolling; (14) Use a winding device to tightly wind a layer of OPP film on the outer layer of the above-mentioned rolled tubular cylinder; (15) Place the tubular part wound with OPP film in a constant temperature oven for baking, the temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes; (16) Take out the core and remove the outer OPP film from the baked tubular part; it is the blank of the hollow cylinder.

[0027] (17) Grind the above-mentioned hollow cylinder blank to a specified size of φ5.50 mm - φ6.50 mm, and the remaining special resin cloth on the outer layer of the ground hollow cylinder shall not exceed 10% of the original resin cloth volume, that is, the hollow cylinder is made.

[0028] S1.2. Rolling of the stepped layer (21)According to the dimensional requirements of the stepped layer, take a carbon fiber composite prepreg containing epoxy resin that meets the thickness of the stepped size, cut it into the specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (22)Place the cut carbon fiber composite prepreg on the workbench, place the hollow cylinder as the core on top of the carbon fiber composite prepreg, align the stepped surfaces corresponding to the stepped transition layer, and at the same time align and tightly attach the edge of the prepreg to the hollow or solid cylinder, then roll it one circle to form a stepped cylinder shape; (23)On the outermost diameter layer of the above-mentioned rolled stepped cylinder shape, roll a special resin cloth. When rolling, it must be aligned and tightly attached before proceeding; (24)Insert a special iron core into the hollow cylinder and fix it firmly. The iron core and the hollow cylinder adopt an interference fit.

[0029] (25)Use a winding device to tightly wind a layer of OPP film on the outer layer of the above-mentioned rolled stepped cylinder; (26)Put the stepped cylinder part wound with OPP film into a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes; (27)After baking, pull out the core from the tubular part of the stepped cylinder part and remove the outer OPP film, which is the blank of the racket shaft.

[0030] (28)Grind the outermost diameter of the above-mentioned stepped cylinder part to the specified size of φ6.2mm - φ7.2mm, and at the same time grind the stepped transition layer as required. The remaining special resin cloth on the outer layer of the ground tubular part shall not exceed 10% of the original resin cloth volume. According to the dimensional requirements of the stepped layer, after cutting both ends of the ground tubular or solid cylinder part to the specified length of 280mm - 320mm, the badminton racket shaft is made.

[0031] S2. Manufacturing of the racket frame strip S2.1 Cut a lightweight non-woven fiber cloth evenly coated with a foamed resin layer into the specified size as required. Its width is determined according to the average perimeter of the racket frame cross-section, with a width of 5 - 15mm, and its length is determined according to the racket frame perimeter, with a length less than 780mm; S2.2 Cut the carbon fiber composite prepreg containing epoxy resin into the specified size as required. Its length is determined according to the racket frame perimeter, with a length less than 780mm, and its width is controlled by weight. The weight of the carbon fiber composite prepreg is controlled within 35 grams; by weight percentage, the weight ratio of the content of epoxy resin in the carbon fiber composite prepreg is 30% - 45%; S2.3. Place the cut carbon fiber composite prepreg on the workbench, align one side of the prepreg with the marked straight line on the workbench, then place the cut lightweight non-woven fiber cloth on top of the carbon fiber composite prepreg with the foaming resin layer of the lightweight non-woven fiber cloth facing up, and then roll it into a tube to obtain a carbon fiber composite prepreg tube with foaming resin in the inner cavity; S3. Racket preforming S3.1. Preform the rolled carbon fiber composite prepreg tube on a preforming mold to obtain a preformed racket frame. The preforming mold is used to control the racket frame circumference. Insert joints at both ports of the preformed racket frame, and then connect the joints to the upper end of the racket shaft; Paste a carbon fiber composite prepreg connection patch at the tee joint where the preformed racket frame is joined to the upper end of the racket shaft to position and fix the joints, racket frame, and upper end of the racket shaft to obtain a positioned racket preform; S3.2. Remove the positioned racket preform from the preforming mold. According to requirements, paste another carbon fiber composite prepreg connection patch at the joints where the preformed racket frame is joined to the racket shaft and the joints to obtain a carbon fiber badminton racket preform; S4. Blank forming S4.1. Place the preformed carbon fiber badminton racket preform into a racket forming mold, close and fasten the mold, and then move the mold into a heating device for heating. The heating temperature is 145 - 155 °C and the time is 30 - 60 minutes; The carbon fiber badminton racket preform cures and forms during the heating process. During the heating of the mold, the foaming resin in the inner cavity of the racket frame of the badminton racket preform continuously expands, forming a pressure of 5 kg / cm 2 ~12 kg / cm 2 in the inner cavity of the racket frame, and the racket frame is shaped along the inner cavity of the mold to form a racket frame shape; S4.2. When the racket forming mold reaches the heating time, remove the racket forming mold from the heating device and place it in a cooling device for cooling. The cooling temperature is 5 - 15 °C and the cooling time is 5 - 10 minutes. Wait until the mold cools to 45 - 55 °C, move the racket forming mold to the workbench, open the mold, and take out the formed carbon fiber composite badminton racket blank; S5. Drilling and grinding the racket frame S5.1. After forming the badminton racket blank, drill holes in the racket frame of the badminton racket blank; S5.2. Fill the slight unevenness on the outer surface of the racket frame with EP series putty, then place it in an oven at a temperature of 75 - 80 °C for 2 - 3 hours. After the EP series putty is completely cured, use sandpaper to polish the surface of the racket blank flat; S6. Assemble the front sleeve and the racket handle S6.1. Apply 0.5 ± 0.1 g of two-component adhesive to the lower end of the racket shaft of the badminton racket blank. At the same time, apply 0.5 - 1.0 g of two-component adhesive to the joint hole between the handle and the racket shaft and on the joint surface between the front sleeve and the handle, and connect the front sleeve, the handle and the racket blank shaft together; S6.2. Cure the two-component adhesive at room temperature for 12 - 24 hours to firmly join the front sleeve, the handle and the racket blank shaft; S6.3. After firm joining, fix the countersunk screw at the joint of the front end of the handle and the rear end of the racket shaft to fixedly connect the handle and the racket shaft, and the head of the countersunk screw is flush with the surface of the handle; S7. Painting and beautifying processing of the racket frame, racket shaft and front sleeve After the front sleeve, the handle and the racket blank shaft are joined, perform painting and beautifying processing on the racket frame, racket shaft and front sleeve according to the design requirements, and spray various colors of paint and transfer various shaped transfer patterns on the racket frame, racket shaft and front sleeve; S8. Manufacture the racket After the racket frame, racket shaft and front sleeve are painted and beautified, insert the grommets into the holes of the racket frame, assemble the rear sleeve at the rear end of the handle, wrap the handle grip on the outer surface of the handle, and then thread the strings through the racket frame according to the stringing method and tighten the strings to the required tension on the badminton racket stringing machine to manufacture a badminton racket with excellent performance and beautiful appearance.

[0032] For the badminton racket of the present invention, there are obvious differences in the rigidity and elasticity of the racket shaft in the front and rear parts. When the overall rigidity of the racket shaft of the badminton racket of the present invention is the same as the overall rigidity of the existing racket shaft: (1) When using the badminton racket of the present invention, since the rigidity of the front end of the racket shaft in the length direction is softer than that of the existing racket, and the rigidity of the rear end is harder, after the racket face hits the ball, the racket shaft generates a larger deformation at the front end position, and the downward pressure of the racket face during hitting is better than that of the existing racket, effectively solving the problem of insufficient downward pressure caused by the harder racket shaft of the existing racket.

[0033] (2) When using the badminton racket of the present invention, since the racket shaft generates a larger deformation at the front end position than the existing racket after the racket face hits the ball, the elastic energy at the bending position is better than that of the existing racket, and the distance from the hitting point to the rebound point of the racket shaft is smaller than that of the existing racket, the rebound speed of the racket face is relatively faster. Therefore, the hit ball has a faster speed and stronger force, effectively solving the problems of insufficient rebound speed and offensive power of the existing racket.

[0034] (3) When using the badminton racket designed and manufactured by the present invention, since the swing arm length of the racket face during swinging is relatively shorter than that of the existing racket, the swing period of the racket face will be smaller than that of the existing racket, and the reset speed of the racket face is faster than that of the existing racket, effectively solving the stability problem during continuous hitting of the racket and improving the quality of continuous hitting of the racket.

[0035] (4) The badminton racket designed and manufactured by using the present invention has a softer rigidity at the bent (elastic) position of the racket shaft than other parts of the racket. The racket is divided into two parts at the bent (elastic) position of the racket shaft, and the two parts of the racket are (softly) connected through the bent (elastic) position. After hitting the ball, the racket has a hitting principle similar to that of a nunchaku (whip). Due to the action of inertia force when the racket head hits the ball, the hitting force will increase and the hitting speed will accelerate. The vibration feedback to the hitter after the racket hits the ball is significantly reduced, thereby reducing sports injuries. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a schematic structural diagram of the solid racket shaft badminton racket according to Embodiment 1 of the present invention.

[0037] Figure 2 is Figure 1 enlarged view of part Ⅰ of

[0038] Figure 3 It is a schematic structural diagram of the hollow racket shaft badminton racket according to Embodiment 2 of the present invention.

[0039] Figure 4 is Figure 3 enlarged view of part Ⅰ of

[0040] Figure 5 It is a schematic structural diagram of the solid racket shaft according to Embodiment 1 of the present invention.

[0041] Figure 6 It is a schematic structural diagram of the hollow racket shaft according to Embodiment 2 of the present invention.

[0042] Figure 7 It is a comparison diagram of the racket shaft deformation between the badminton racket according to the embodiment of the present invention and the existing racket.

[0043] Figure 8 It is a comparison diagram of the racket face swing between the badminton racket according to the embodiment of the present invention and the existing racket.

[0044] Figure 9 It is a comparison diagram of the downward hitting flight and landing point between the badminton racket according to the embodiment of the present invention and the existing racket.

[0045] Figure 1 、 Figure 3 In

[0046] Figure 2 、 Figure 4 、 Figure 5 、 Figure 6In: 2-0. Hollow cylinder; 2-1. Polymer material; 2-2. Solid cylinder one; 2-3. Solid cylinder two; D0. Outer diameter of solid cylinder one; D1. Minimum outer diameter of the racket shaft; D2. Maximum outer diameter of the racket shaft; D3 and D4. Outer diameters at the stepped transition; d0. Outer diameter of the polymer material; d. Inner diameter of the hollow racket shaft; L0. Length of the part of the racket shaft with the minimum outer diameter, L1 and L2. Lengths of the stepped transition parts; L. Total length of the racket shaft.

[0047] Figure 7 In: A and A1 are the swinging angles of the racket; B and B1 are the distances from the same hitting point to the bending point of the racket shaft.

[0048] Figure 8 In: S and S1 are the swinging arm lengths of the racket face.

[0049] Figure 9 In: C and C1 are the flying distances of the badminton after hitting; H and H1 are the distances to the hitting landing points. Detailed implementation mode

[0050] The present invention will be further described in detail below with reference to the accompanying drawings and in conjunction with embodiments. However, the present invention is not limited to the given examples.

[0051] A carbon fiber badminton racket has: An annular racket frame 1, a racket shaft 2 connected to the racket frame 1, and a joint 3 for fixedly connecting the racket frame 1 and the racket shaft 2. The rear end of the racket shaft 2 is fixedly connected with a racket handle 5. The front end of the racket handle 5 has a tapered front sleeve 4. The surface of the racket handle 5 is wound with a grip leather 7 for anti-slip. The racket frame 1 is provided with a racket string 9 through a string protector 8 to form a racket net.

[0052] The racket shaft 2 is of solid or hollow structure; when it is of hollow structure, the inner diameter of the racket shaft 2 is uniform; whether the racket shaft 2 is of solid or hollow structure, the outer diameter of the racket shaft 2 gradually increases in a stepped shape, with the end close to the racket frame 1 being the smaller end and the end close to the racket handle 5 being the larger end.

[0053] The rear end of the racket handle 5 has a rear sleeve 6.

[0054] The further improved technical solution of the present invention is as follows: Preferably, the racket shaft 2 is formed by 2 to 6 cylinders with different lengths and outer diameters wrapped layer by layer, so as to form a racket shaft 2 with 1 to 5 levels of steps.

[0055] The outer diameter dimension of the smallest end of the hitting rod 2 is between φ5.5mm and φ6.5mm, and the outer diameter dimension of the largest end is between φ6.2mm and φ7.2mm; the difference between the outer diameter of the largest end and the outer diameter of the smallest end of the hitting rod 2 is between 0.20 and 1.20mm, and the difference in outer diameter between adjacent two levels of steps is between 0.10 and 0.30mm.

[0056] Preferably, the length of the segmented part of the smallest end of the hitting rod 2 is 80 - 200mm, and the length of the segmented part of the largest end is 120 - 240mm; when the number of steps is greater than 3, the length of the adjacent stepped transition section is 5 - 60mm.

[0057] The elasticity of the smallest outer diameter part of the hitting rod 2 is better than that of the largest outer diameter part; the rigidity of the largest outer diameter part of the hitting rod 2 is harder than that of the smallest outer diameter part; the torsional deformation resistance of the largest outer diameter part of the hitting rod 2 is smaller than that of the smallest outer diameter part.

[0058] One end of the smallest outer diameter part of the hitting rod 2 is used as the front end of the hitting rod 2 to connect with the racket frame 1, and one end of the largest outer diameter part is used as the rear end of the hitting rod 2 to connect with the front sleeve 4 and the racket handle 5.

[0059] Preferably, when the hitting rod 2 has a hollow structure, the inner diameter dimension of the hollow part is not greater than φ5.0mm, the length is 280 - 320mm, and the hitting rod 2 is made of carbon fiber composite material.

[0060] Preferably, when the hitting rod 2 is a solid structure, the hitting rod 2 is manufactured by a three - time molding process, and from the inside out, it is successively a solid cylinder one 2 - 2, a solid cylinder two 2 - 3 and a stepped layer. The solid cylinder one 2 - 2 is composed of a cylinder made of carbon fiber material and a polymer material 2 - 1 filled inside; the diameter of the polymer material 2 - 1 filled inside the solid cylinder one 2 - 2 is φ0.6 - φ1.2mm, and the diameter of the solid cylinder one 2 - 2 is φ2.20mm - φ2.80mm.

[0061] Preferably, when the hitting rod 2 has a hollow structure (inner diameter ≤ φ5.0mm), the hitting rod 2 is manufactured by a two - time molding process, including a hollow cylinder 2 - 0 and a stepped layer.

[0062] Specifically, the internally filled polymer material 2 - 1 is a shock - absorbing material, specifically a reinforced fiber resin. Embodiment

[0063] Such as Figure 1 、 Figure 2 And Figure 5As shown in the figure, a carbon fiber badminton racket includes a racket frame 1, a racket shaft 2, a special joint 3, a front sleeve 4, a racket handle 5, a rear sleeve 6, a grip 7, a grommet 8 and a string 9. The racket frame 1 forms a ring shape. The racket frame 1 is connected to the front end of the racket shaft 2. A special joint 3 is provided at the connection part between the racket frame 1 and the racket shaft 2. The rear end of the racket shaft 2 is installed with a front sleeve 4 and a racket handle 5. A grip 7 is wound around the racket handle 5. A rear sleeve 6 is installed at the rear part of the racket handle 5. A string 9 is threaded through the racket frame 1 via a grommet 8.

[0064] The racket shaft 2 is of solid structure. The maximum outer diameter D2 is φ6.40mm, and the minimum outer diameter D1 is φ5.80mm. The outer diameter gradually decreases in a stepped shape from the front to the rear. The stepped transition length is 30mm. The length L0 of the outer cylinder with the minimum outer diameter is 130mm. The total length L of the racket shaft is 295mm.

[0065] As Figure 5 shown in the figure, the racket shaft 2 of the badminton racket is composed of stepped cylinders with different lengths and outer diameters tightly combined. The intermediate transition diameter D3 is φ6.00mm, and the stepped transition length L1 is 15mm. D3 is φ6.20mm, and the stepped transition length L2 is 15mm. The end with the minimum outer diameter D1 of the racket shaft 2 is connected to the racket frame 1 as the front end of the racket shaft 2, and the end with the maximum outer diameter D2 is connected to the front sleeve 4 and the racket handle 5 as the rear end of the racket shaft 2.

[0066] The racket shaft 2 of the badminton racket is made of carbon fiber composite material and polymer material.

[0067] The racket shaft 2 is of solid structure. The racket shaft is manufactured by a three - time molding process, including a solid cylinder one 2 - 2, a solid cylinder two 2 - 3, and a stepped layer. The solid cylinder one 2 - 2 is composed of a cylinder made of carbon fiber material and a polymer material 2 - 1 filled inside. The diameter d0 of the central polymer material 2 - 1 in the solid cylinder one 2 - 2 is φ0.7mm, and the diameter D0 of the solid cylinder one 2 - 2 is φ2.50mm.

[0068] For the racket shaft 2 of the badminton racket, the elasticity of the part with the minimum outer diameter D1 is better than that of the part with the maximum outer diameter D2; the rigidity of the part with the maximum outer diameter D2 of the racket shaft is harder than that of the part with the minimum outer diameter D1; the resistance to torsional deformation of the part with the maximum outer diameter D2 of the racket shaft is smaller than that of the part with the minimum outer diameter D1.

[0069] A manufacturing method of a carbon fiber badminton racket is realized by the following steps: Step 1, racket rod manufacturing: The racket rod 2 from outside to inside successively includes a stepped layer, a solid cylinder two 2-3, and a solid cylinder one 2-2. The solid cylinder two 2-3 and the solid cylinder one 2-2 are tightly combined. The stepped layer consists of a maximum outer diameter layer D2, a transition layer, and a minimum outer diameter layer D1. The maximum outer diameter layer D2, the transition layers D3, D4 are tightly joined on the solid cylinder two 2-3; Step 1, rolling of the solid cylinder one 2-2 1-1 According to the requirement that the outer diameter dimension D0 of the solid cylinder one 2-2 is φ2.50 mm, take the carbon fiber composite prepreg that meets the solid cylinder one 2-2 and cut it into the following dimensions as required: (1), Take the Toray M40X carbon cloth produced in Japan with FAW = 100, resin content 30%, and an angle of 0 degrees, and cut a size of 67 mm X 505 mm into 1 piece; (2), One nylon 66 thread with a diameter of 0.7 mm and a length of 505 mm.

[0070] 1-2 Place the laminated carbon cloth on the workbench, place the nylon 66 thread on the carbon cloth, and at the same time align the edge of the carbon cloth with the nylon 66 thread in a straight line and stick them tightly with transparent tape, and roll it into a solid cylinder shape; 1-3 Put the rolled solid cylinder one 2-2 into the mold and fix the mold; 1-4 Put the mold into a constant temperature oven for baking, keep the temperature in the oven at 150 ± 2 °C, and the baking time is 30 - 60 minutes; 1-5 Take out the mold, wait for the mold to cool to room temperature, open the mold, and take out the cured solid cylinder one 2-2 blank.

[0071] 1-6 Grind the above solid cylinder one 2-2 blank to the specified size of φ2.50 mm, that is, make the solid cylinder one 2-2.

[0072] Step 2, rolling of the solid cylinder two 2-3 2-1 According to the requirement that the outer diameter dimension D1 of the solid cylinder two 2-3 is φ5.80 mm, take the carbon fiber composite prepreg that meets the solid cylinder two 2-3 and cut it into the following dimensions as required: (1), Take the Toray M50J carbon cloth produced in Japan with FAW = 100, resin content 24%, and an angle of 45 degrees, and cut a size of 83 mm X 320 mm into 2 pieces; (2), Take the Toray M40J carbon cloth produced in Japan with FAW = 100, resin content 24%, and an angle of 0 degrees, and cut a size of 49 mm X 320 mm into 1 piece; (3), Press the carbon cloths of the above cut sizes together according to the specified requirements.

[0073] 2-2 Place the laminated carbon cloth on the workbench, place the solid cylinder 2-2 on top of the carbon cloth. At the same time, align the edge of the carbon cloth with the solid cylinder 2-2 in a straight line and press it tightly, then fix it with transparent tape and roll it into the shape of a solid cylinder. 2-3 Take Toray T1100 carbon cloth made in Japan with FAW = 100, resin content 30%, and an angle of 0 degrees, cut 1 piece with a size of 36mm X 320mm, and wrap it around the outer layer of the above-mentioned rolled solid cylinder. When rolling, it must be aligned and pressed tightly before proceeding. 2-4 Take fiberglass resin cloth with FAW = 100, resin content 36%, and an angle of (0 + 90) degrees, cut 1 piece with a size of 18mm X 320mm, and wrap it around the outer layer of the above-mentioned rolled solid cylinder. When rolling, it must be aligned and pressed tightly before proceeding. 2-5 Use a winding device to tightly wind a layer of OPP film around the outer layer of the above-mentioned rolled solid cylinder. 2-6 Put the solid cylinder wrapped with OPP film into a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes. 2-7 After the baked solid cylinder is cooled, remove the outer OPP film, which is the blank of the solid cylinder 2-3. 2-8 Grind the above-mentioned blank of the solid cylinder 2-3 to the specified D1 size of φ5.80mm. The remaining special resin cloth on the outer layer of the ground solid cylinder should not exceed 10% of the original resin cloth volume, thus making the solid cylinder 2-3. Step 3: Winding of the stepped transition layer 3-1 According to the dimensional requirements of the step: L0 is 130mm, D1 is φ5.80mm; L1 is 15mm, D3 is φ6.00mm; L2 is 15mm, D3 is φ6.20mm; D2 is φ6.40mm.

[0074] (1) Take Toray M40J carbon cloth made in Japan with FAW = 50, resin content 30%, and an angle of 45 degrees, cut 2 pieces with a size of 18.6mm X 180mm; (2) Take Toray T800 carbon cloth made in Japan with FAW = 50, resin content 33%, and an angle of 45 degrees, cut 2 pieces with a size of 18.9mm X 165mm; (3) Take Toray T800 carbon cloth made in Japan with FAW = 50, resin content 33%, and an angle of 45 degrees, cut 2 pieces with a size of 19.2mm X 150mm; (4) Take fiberglass resin cloth with FAW = 100, resin content 36%, and an angle of (0 + 90) degrees, cut 1 piece with a size of 21.0mm X 150mm.

[0075] (5) Press the carbon cloth cut to the above - specified size together according to the specified requirements. At the same time, evenly coat a layer of resin on the stepped surface. The resin model is commercially available ADK50.

[0076] 3 - 2 Evenly coat a layer of resin on the outer surface of the stepped joint part of the solid cylinder. The resin model is commercially available ADK50.

[0077] 3 - 3 Place the above - pressed carbon cloth on the workbench. Place the solid cylinder coated with resin as the core on top of the carbon fiber composite prepreg. At the same time, align the edge of the carbon cloth with the solid cylinder and press it tightly, then roll it into a solid cylinder with the resin cloth on the outer surface of the cylinder. 3 - 4 Align the stepped surfaces corresponding to the stepped transition layer and closely fit the stepped transition surfaces.

[0078] 3 - 5 Use a winding device to tightly wind a layer of OPP film on the outer layer of the above - rolled solid cylinder. 3 - 6 Place the solid cylinder wound with OPP film into a constant - temperature oven for baking. The temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes. 3 - 7 Remove the outer OPP film from the baked solid stepped cylinder, which is the blank of the racket shaft 2.

[0079] 3 - 8 Grind the maximum outer diameter D2 of the above - mentioned solid stepped cylinder to the specified size of φ6.4 mm. At the same time, grind the stepped transition layer as required. The residual of the special resin cloth on the outer layer of the ground tubular part shall not exceed 10% of the original resin cloth volume. After cutting the two ends of the ground solid cylinder to the specified length of 295 mm according to the requirement that the size L0 of the step is 130 mm, the badminton racket shaft 2 is made.

[0080] Second step: Manufacturing of the racket frame 1 strip Step 1: Cut the lightweight non - woven shock - absorbing fiber cloth evenly coated with a foamed resin layer (density 200 g / ㎡) into the specified size according to the requirements. Its width is determined according to the average perimeter of the racket frame cross - section, with a width of 8 - 9 mm, and its length is determined according to the perimeter of the racket frame, with a length of 700 mm. Step 2: Cut the 30 - degree woven carbon fiber composite prepreg with the specification of FAW130 into the specified size according to the requirements. The specified size is 74 mm × 692 mm. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 35%. Cut the 10 - degree woven carbon fiber composite prepreg with the specification of FAW150 into the specified size according to the requirements. The specified size is 59 mm × 692 mm. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 35%. The carbon fiber composite material prepreg fabric with a 0-degree weave and a specification of FAW75 is cut into a specified size as required, and the specified size is 10mm×690mm. The content of epoxy resin in the carbon fiber composite material prepreg fabric is 35%; The carbon fiber composite material prepreg fabric with a 0-degree weave and a specification of FAW125 is cut into a specified size as required, and the specified size is 10mm×690mm. The content of epoxy resin in the carbon fiber composite material prepreg fabric is 35%; Step 3, place the above-mentioned cut carbon fiber composite material prepregs on the workbench in turn and combine them as required, align one side of the prepreg with the marked straight line on the workbench, and then place the cut lightweight non-woven shock-absorbing fiber cloth on the carbon fiber composite material prepreg with the foamed resin layer facing upward, and then roll it into a tube to obtain a carbon fiber composite material prepreg tubular part with an inner cavity containing foamed resin.

[0081] Step 3: Pre-shape the frame 1 Step 1, preforming a rolled carbon fiber composite prepreg tubular member with a foamed resin in the inner cavity on a preforming mold to obtain a preformed racket frame 1, the preforming mold is used to control the circumference of the racket frame 1, inserting a special joint 3 into two ports of the preformed racket frame 1, and then connecting the special joint 3 with the maximum inner diameter end of the racket shaft 2; pasting a carbon fiber composite prepreg connection patch 1-1 at the three-way joint where the preformed racket frame 1 and the upper end of the racket shaft 2 are joined, and the special joint 3, the racket frame 1, and the upper end of the racket shaft 2 are joined and positioned to obtain a well-positioned racket preform; Step 2: remove the positioned racket preform from the preform mold, and stick another carbon fiber composite material prepreg cloth connecting patch 1-1 on the joint between the preform racket frame 1, the racket shaft 2 and the special joint 3 as required to obtain a carbon fiber badminton racket preform.

[0082] Step 4: Blank Forming Step 1, put the preformed carbon fiber badminton racket preform into the racket forming mold, close and buckle the mold, and then move the mold into a heating device for heating at a temperature of 145-155°C for 30-60 minutes; the carbon fiber badminton racket preform is cured and formed during the heating process. During the heating process of the mold, the foaming resin in the inner cavity of the racket frame 1 of the badminton racket preform continuously expands, forming a 5kg / cm 2 ~12kg / cm 2 The racket frame 1 is shaped along the inner cavity of the mold to form a racket frame shape; Step 2: After the racket forming mold reaches the heating time, remove the racket forming mold from the heating device and place it in the cooling device for cooling. The cooling temperature is 5 - 15°C, and the cooling time is 5 - 10 minutes. After the mold is cooled to 45 - 55°C, move the racket forming mold to the workbench, open the mold, and take out the formed carbon fiber composite badminton racket blank. Through such a forming process in different racket molds, high-performance badminton racket blanks with various frame shapes can be obtained.

[0083] Step 5: Drilling and grinding of the racket frame 1 Step 1: After forming the badminton racket blank, drill holes in the racket frame 1 of the badminton racket blank. The drilling can be carried out using a mold or on a programmable automatic drilling machine. Step 2: Fill the slight unevenness on the outer surface of the racket frame 1 with EP series putty, then place it in an oven at a temperature of 75 - 80°C for 2 hours. After the EP series putty is completely cured, use sandpaper to smooth the surface of the racket blank. Step 6: Assembling the front sleeve 4 and the handle 5 Step 1: Apply about 0.5 g of two-component adhesive to the lower end of the racket shaft 2 of the badminton racket blank. At the same time, apply 0.5 - 1.0 g of two-component adhesive to the joint hole between the handle 5 and the racket shaft 2 and on the joint surface between the front sleeve 4 and the handle 5. Connect the front sleeve 4, the handle 5, and the blank racket shaft 2 together on the equipment. The two-component adhesive in this embodiment is produced by ADK, with the model numbers ADK206A and ADK206B, and the ratio (by weight) is ADK206A:ADK206B = 1:0.8.

[0084] Step 2: Cure the two-component adhesive at room temperature for 12 - 24 hours to firmly bond the front sleeve 4, the handle 5, and the blank racket shaft 2. Step 3: After firmly bonding, fix the countersunk screw 10 at the joint between the front end of the handle 5 and the rear end of the racket shaft 2 to fixedly connect the handle 5 and the racket shaft 2. The head of the countersunk screw 10 is flush with the surface of the handle 5.

[0085] Step 7: Painting and beautifying processing of the racket frame 1, racket shaft 2, and front sleeve 4 After the front sleeve 4, the handle 5, and the blank racket shaft 2 are joined, according to the design requirements, perform painting and beautifying processing on the racket frame 1, racket shaft 2, and front sleeve 4, and spray various colors of paint and transfer various shaped transfer patterns on the racket frame 1, racket shaft 2, and front sleeve 4.

[0086] Step 8: Manufacturing the racket After the racket head 1, racket shaft 2, and front sleeve 4 are painted and beautified, a grommet is inserted into the hole of the racket head 1. The back sleeve 6 is assembled at the rear end of the racket handle 5, and a grip 7 is wrapped around the outer surface of the racket handle 5. Then, the racket string 9 is threaded through the racket head 1 according to the stringing method, and the racket string 9 is tightened to the required tension on a badminton racket stringing machine, thus making a badminton racket with excellent performance and beautiful appearance.

[0087] As Figure 3 , Figure 4 and Figure 6 shown, a carbon fiber badminton racket includes a racket head 1, a racket shaft 2, a special joint 3, a front sleeve 4, a racket handle 5, a back sleeve 6, a grip 7, a grommet 8, and a racket string 9. The racket head 1 forms a ring, and the racket head 1 is connected to the front end of the racket shaft 2. A special joint 3 is provided at the connection part between the racket head 1 and the racket shaft 2. The rear end of the racket shaft 2 is installed with a front sleeve 4 and a racket handle 5. A grip 7 is wrapped around the racket handle 5, and a back sleeve 6 is installed at the rear part of the racket handle 5. The racket string 9 is threaded through the racket head 1 via the grommet 8.

[0088] The racket shaft 2 is of a hollow structure. The inner diameter of the hollow structure is φ3.00 mm, the maximum outer diameter D2 is φ6.80 mm, the minimum outer diameter D1 is φ6.40 mm. The outer diameter gradually decreases in a stepped shape from the front to the rear. The stepped transition length is 15 mm. The length L0 of the outer cylinder with the minimum outer diameter is 110 mm, and the total length L of the racket shaft is 295 mm.

[0089] As Figure 6 shown, the racket shaft 2 of the badminton racket is tightly combined by stepped cylinders with different lengths and outer diameters. The intermediate transition diameter D3 is φ6.60 mm, and the stepped transition length L1 is 15 mm. The end with the minimum outer diameter D1 of the racket shaft 2 is used as the front end of the racket shaft 2 to connect with the racket head 1, and the end with the maximum outer diameter D2 is used as the rear end of the racket shaft 2 to connect with the front sleeve 4 and the racket handle 5.

[0090] The racket shaft 2 of the badminton racket is made of carbon fiber composite material.

[0091] The racket shaft 2 of the badminton racket is manufactured by a secondary molding process.

[0092] For the racket shaft 2 of the badminton racket, the elasticity of the part with the minimum outer diameter D1 is better than that of the part with the maximum outer diameter D2; the rigidity of the part with the maximum outer diameter D2 of the racket shaft is harder than that of the part with the minimum outer diameter D1; the resistance to torsional deformation of the part with the maximum outer diameter D2 of the racket shaft is smaller than that of the part with the minimum outer diameter D1.

[0093] A manufacturing method of a carbon fiber badminton racket is realized by the following steps: Step 1. Manufacturing of the racket shaft: The racket shaft sequentially includes a stepped layer and a hollow cylinder from outside to inside. The stepped layer is composed of a maximum outer diameter layer D2, a transition layer D3, and a minimum outer diameter layer D1. The maximum outer diameter layer D2 and the transition layer D3 are tightly joined onto the hollow cylinder D1. Step 1. Rolling of the hollow cylinder 1-1 According to the requirement that the outer diameter dimension D1 of the hollow cylinder is φ6.40mm, take carbon fiber composite prepreg containing epoxy resin and of different models that meets the requirements of the hollow cylinder FAW, and cut it into the following dimensions as required: (1). Take Toray M40J carbon cloth made in Japan with FAW = 116, resin content of 33%, and an angle of 45 degrees, and cut 2 pieces with a size of 76mm X 320mm; (2). Take Toray T1100 carbon cloth made in Japan with FAW = 100, resin content of 30%, and an angle of 0 degrees, and cut 1 piece with a size of 35mm X 320mm; (3). Press the carbon cloth cut to the above sizes together according to the specified requirements.

[0094] 1-2 Place the pressed carbon cloth on the workbench, place a φ3mm special core on the carbon cloth. At the same time, align and tightly stick the edge of the carbon cloth with the core and fix it with transparent tape, and roll it into a hollow cylinder shape; 1-3 Take Toray T700 carbon cloth made in Japan with FAW = 125, resin content of 30%, and an angle of 0 degrees, and cut 1 piece with a size of 38mm X 320mm, and wrap it outside the above-mentioned rolled hollow cylinder. When rolling, it must be aligned and tightly stuck before proceeding; 1-4 Take a fiberglass resin cloth with FAW = 100, resin content of 36%, and an angle of (0 + 90) degrees, and cut 1 piece with a size of 21mm X 320mm, and wrap it outside the above-mentioned rolled hollow cylinder. When rolling, it must be aligned and tightly stuck before proceeding; 1-5 Use winding equipment to tightly wind a layer of OPP film on the outer surface of the above-mentioned cylinder rolled into a tube shape; 1-6 Put the tube-shaped cylinder wound with OPP film into a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2°C, and the baking time is 30 - 60 minutes; 1-7 Take out the core from the baked tube-shaped cylinder and remove the outer OPP film; 1-8 Grind the above-mentioned tube-shaped cylinder to the specified size of φ6.40mm. The residual resin cloth on the outer layer of the ground tube-shaped cylinder shall not exceed 10% of the original resin cloth volume, that is, the hollow cylinder is made; Step 2. Rolling of the stepped transition layer 2-1 According to the dimensional requirements of the ladder: L0 is 110 mm, D1 is φ6.40 mm; L1 is 15 mm, D3 is φ6.60 mm; D2 is φ6.80 mm.

[0095] (1) Take Toray T800 carbon cloth produced in Japan with FAW = 50, resin content of 33%, and an angle of 45 degrees, and cut 2 pieces with dimensions of 20.6 mm X 190 mm. (2) Take Toray T800 carbon cloth produced in Japan with FAW = 50, resin content of 33%, and an angle of 45 degrees, and cut 2 pieces with dimensions of 21.2 mm X 175 mm. (3) Take fiberglass resin cloth with FAW = 100, resin content of 36%, and an angle of (0 + 90) degrees, and cut 1 piece with dimensions of 22 mm X 175 mm.

[0096] (4) Press the carbon cloth cut to the above dimensions together according to the specified requirements. At the same time, evenly coat a layer of resin on the ladder surface. The resin model is commercially available ADK50.

[0097] 2-2 Evenly coat a layer of resin on the outer surface of the joint part of the hollow cylinder ladder. The resin model is commercially available ADK50. 2-3 Place the pressed carbon cloth on the workbench. Place the hollow cylinder coated with resin as the core on the carbon fiber composite prepreg. At the same time, align the edges of the carbon cloth with the hollow cylinder and press them tightly, then roll them into a cylinder. The resin cloth is on the outer surface of the cylinder. Align the corresponding ladder surfaces of the ladder transition layer and press the ladder transition surfaces tightly together.

[0098] 2-4 Insert a special iron core into the hollow cylinder and fix it firmly. The iron core and the hollow cylinder adopt an interference fit.

[0099] 2-5 Use winding equipment to tightly wind a layer of OPP film on the outer layer of the cylinder rolled above. 2-6 Place the cylinder wound with OPP film in a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes. 2-7 Remove the middle iron core and the outer OPP film from the baked cylinder, and it is the blank of the racket handle.

[0100] 2-8 Grind the maximum outer diameter D2 of the above cylinder to the specified size of φ6.8 mm. At the same time, grind the ladder transition layer as required. The remaining special resin cloth on the outer layer of the ground tubular part shall not exceed 10% of the original resin cloth volume. According to the requirement of the ladder size L0 of 110 mm, cut the two ends of the ground cylinder to the specified length of 295 mm, and then the badminton racket handle 2 is made.

[0101] Step 2: Manufacturing of the long strip of the racket frame 1 Step 1: Cut the lightweight non-woven shock-absorbing fiber cloth evenly coated with a foaming resin layer (density 200 g / ㎡) into specified dimensions as required. Its width is determined according to the average perimeter of the racket frame cross-section, with a width of 8 - 9 mm, and its length is determined according to the perimeter of the racket frame, with a length of 700 mm; Step 2: Cut the carbon fiber composite pre-impregnated cloth woven at 30 degrees and with a specification of FAW130 into specified dimensions as required. The specified dimensions are 78 mm × 692 mm. By weight percentage, the content of epoxy resin in the carbon fiber composite pre-impregnated cloth is 35%; Cut the carbon fiber composite pre-impregnated cloth woven at 10 degrees and with a specification of FAW150 into specified dimensions as required. The specified dimensions are 56 mm × 692 mm. By weight percentage, the content of epoxy resin in the carbon fiber composite pre-impregnated cloth is 35%; Cut the carbon fiber composite pre-impregnated cloth woven at 0 degrees and with a specification of FAW75 into specified dimensions as required. The specified dimensions are 10 mm × 690 mm. The content of epoxy resin in the carbon fiber composite pre-impregnated cloth is 35%; Cut the carbon fiber composite pre-impregnated cloth woven at 0 degrees and with a specification of FAW125 into specified dimensions as required. The specified dimensions are 10 mm × 690 mm. The content of epoxy resin in the carbon fiber composite pre-impregnated cloth is 35%; Step 3: Place the above-mentioned cut carbon fiber composite pre-impregnated cloth on the workbench in sequence and combine them as required. One side of the pre-impregnated cloth is aligned with the marked straight line on the workbench, then place the cut lightweight non-woven shock-absorbing fiber cloth on top of the carbon fiber composite pre-impregnated cloth with the foaming resin layer facing up, and then roll it into a tube to obtain a carbon fiber composite pre-impregnated cloth tubular part with a foaming resin inside the cavity.

[0102] Step 3: Pre-forming of the racket frame 1 Step 1: Pre-form the rolled carbon fiber composite pre-impregnated cloth tubular part with a foaming resin inside the cavity on a pre-forming mold to obtain a pre-formed racket frame 1. The pre-forming mold is used to control the perimeter of the racket frame 1. Insert special connectors 3 at both ports of the pre-formed racket frame 1, and then connect the special connectors 3 to the minimum inner diameter end of the racket shaft 2; Paste a carbon fiber composite pre-impregnated cloth connection patch 1-1 at the tee joint where the pre-formed racket frame 1 and the upper end of the racket shaft 2 are joined to position the special connectors 3, the racket frame 1, and the upper end of the racket shaft 2, and obtain a positioned badminton racket pre-form; Step 2: Remove the positioned badminton racket pre-form from the pre-forming mold. According to requirements, paste another carbon fiber composite pre-impregnated cloth connection patch 1-1 at the joint of the pre-formed racket frame 1, the racket shaft 2, and the special connectors 3 to obtain a pre-formed carbon fiber badminton racket.

[0103] Step 4: Blank Molding Step 1: Place the pre-shaped carbon fiber badminton racket preform into the racket molding die, close and fasten the die, then move the die into the heating device for heating. The heating temperature is 145 - 155 °C and the time is 30 - 60 minutes. The carbon fiber badminton racket preform cures and forms during heating. During the heating of the die, the foaming resin in the inner cavity of the racket frame 1 of the badminton racket preform continuously expands, forming a pressure of 5 kg / cm 2 ~12 kg / cm 2 in the inner cavity of the racket frame 1, and the racket frame 1 is shaped along the inner cavity of the die to form the racket frame shape. Step 2: When the racket molding die reaches the heating time, remove the racket molding die from the heating device and place it in the cooling device for cooling. The cooling temperature is 5 - 15 °C and the cooling time is 5 - 10 minutes. Wait until the die cools to 45 - 55 °C, then move the racket molding die to the workbench, open the die, and take out the formed carbon fiber composite badminton racket blank. Through such a molding process in different racket dies, high-performance badminton racket blanks with various frame shapes can be obtained.

[0104] Step 5: Drilling and Grinding of Racket Frame 1 Step 1: After forming the badminton racket blank, drill holes in the racket frame 1 of the badminton racket blank. Drilling can be carried out using a die or on a programmable automatic drilling machine. Step 2: Fill the slight unevenness on the outer surface of the racket frame 1 with EP series putty, then place it in an oven at a temperature of 75 - 80 °C for 2 hours. After the EP series putty is completely cured, use sandpaper to grind the surface of the racket blank flat. Step 6: Assembling Front Sleeve 4 and Handle 5 Step 1: Apply about 0.5 g of two-component adhesive to the lower end of the racket shaft 2 of the badminton racket blank. At the same time, apply 0.5 - 1.0 g of two-component adhesive to the joint hole between the handle 5 and the racket shaft 2 and the joint surface between the front sleeve 4 and the handle 5, and connect the front sleeve 4, handle 5 and the blank racket shaft 2 together on the equipment. The manufacturer of the two-component adhesive in this embodiment is ADK, the model numbers are ADK206A and ADK206B, and the ratio (by weight) is ADK206A:ADK206B = 1:0.8.

[0105] Step 2: Cure the two-component adhesive at room temperature for 12 - 24 hours to firmly join the front sleeve 4, handle 5 and the blank racket shaft 2. Step 3: After firm joining, fix the countersunk screw 10 at the joint between the front end of the handle 5 and the rear end of the racket shaft 2 to fixedly connect the handle 5 and the racket shaft 2. The head of the countersunk screw 10 is flush with the surface of the handle 5.

[0106] Step 7: Painting and beautifying the racket head 1, the racket shaft 2, and the front sleeve 4 After the front sleeve 4 and the racket handle 5 are joined to the blank racket shaft 2, the racket head 1, the racket shaft 2, and the front sleeve 4 are subjected to painting and beautifying processing according to the design requirements. Various colors of paint are sprayed on the racket head 1, the racket shaft 2, and the front sleeve 4, and transfer patterns of various shapes are transferred.

[0107] Step 8: Manufacturing the badminton racket After the painting and beautifying processing of the racket head 1, the racket shaft 2, and the front sleeve 4, grommets are inserted into the holes of the racket head 1. A rear sleeve 6 is assembled at the rear end of the racket handle 5, and a grip 7 is wrapped around the outer surface of the racket handle 5. Then, the badminton strings 9 are threaded through the racket head 1 according to the stringing method, and the badminton strings 9 are tightened to the required tension on a badminton racket stringing machine to manufacture a badminton racket with excellent performance and beautiful appearance.

[0108] The badminton racket designed and manufactured in the embodiment (see Figures 1, 3, Figure 2 Figure 3, Figure 5 Figure 6, Figure 7 , Figure 8 and Figure 9 ) has the following characteristics compared with the existing rackets: (1) For the badminton racket designed and manufactured in this embodiment, the position of the bending point of the racket shaft 2 is moved forward to the front half of the racket shaft 2. At the same time, since the rigidity of the front half of the racket shaft 2 is softer than that of the existing racket shaft, the deformation of the front part of the racket shaft 2 is larger, and the downward pressure of the racket face during hitting is better than that of the existing racket, and the power of the racket attack will be enhanced.

[0109] (2) For the badminton racket designed and manufactured in this embodiment, since the rigidity of the front end of the racket shaft 2 is softer and the rigidity of the rear end is harder in the length direction, the position of the bending point of the racket shaft 2 is moved forward to the front half of the racket shaft 2. After the racket face hits the ball, the racket shaft 2 generates a large deformation and elastic energy in the front half. At the same time, the distance from the hitting point of the racket face to the maximum deformation point of the racket shaft 2 is reduced compared with the existing racket. Therefore, the rebound speed of the racket face after hitting the ball will be significantly improved compared with the existing racket.

[0110] (3) For the badminton racket designed and manufactured in this embodiment, the rear end of the racket shaft 2 has better torsional resistance and harder rigidity in the length direction. Therefore, the stability of the racket during hitting will be improved to a certain extent compared with the existing racket.

[0111] (4) For the badminton racket designed and manufactured in this embodiment, since the rigidity of the bending point position of the racket shaft 2 is softer than other parts of the racket, the racket is divided into two parts at the bending point position of the racket shaft 2. The two parts of the racket are elastically and softly connected through the bending point position. After the racket hits the ball, there is a whipping effect. Due to the action of inertia force and resilience, the hitting force of the racket head during hitting will increase, and the speed of the hit ball will increase.

[0112] (5)The badminton racket designed and manufactured in this embodiment has a relatively shorter swing arm length when the racket face swings compared to the existing rackets. As a result, the swing period of the racket face will be smaller than that of the existing rackets, and the reset speed of the racket face will be faster than that of the existing rackets. This effectively solves the stability problem during continuous hitting of the racket, improves the quality of continuous hitting of the racket, and significantly reduces the vibration feedback to the hitter after the racket strikes, thereby reducing sports injuries.

[0113] In addition to the above embodiments, the present invention may have other implementation manners. Any technical solutions formed by equivalent replacement or equivalent transformation fall within the protection scope required by the present invention.

Claims

1. A carbon fiber badminton racket, characterized in that, It has: A ring-shaped racket frame, a racket shaft connected to the racket frame, and a joint for fixedly connecting the racket frame and the racket shaft. The rear end of the racket shaft is fixedly connected with a racket handle. The front end of the racket handle has a conical front sleeve. The surface of the racket handle is wound with grip tape for anti-slip. The racket frame is strung with strings through string protectors to form a racket net; The racket shaft is of solid or hollow structure; in the case of a hollow structure, the inner diameter of the racket shaft is uniform; whether the racket shaft is of solid or hollow structure, the outer diameter of the racket shaft gradually increases in a stepped manner, with the end close to the racket frame being the smaller end and the end close to the racket handle being the larger end; The rear end of the racket handle has a rear sleeve.

2. A carbon fiber badminton racket according to claim 1, wherein: The racket shaft is formed by 2 to 6 cylinders with different lengths and outer diameters wrapped layer by layer, so as to form a racket shaft with 1 to 5 levels of steps.

3. A carbon fiber badminton racket according to claim 1, wherein: The outer diameter size of the smallest end of the racket shaft is between φ5.5mm and φ6.5mm, and the outer diameter size of the largest end is between φ6.2mm and φ7.2mm; the difference between the outer diameter of the largest end and the outer diameter of the smallest end of the racket shaft is between 0.20 and 1.20mm, and the difference in outer diameter between adjacent two levels of steps is between 0.10 and 0.30mm; The length of the segmented smallest end of the racket shaft is 80 to 200mm, and the length of the segmented largest end is 120 to 240mm; when the number of steps is greater than 3 levels, the length of the adjacent stepped transition section is 5 to 60mm.

4. A carbon fiber badminton racket according to claim 1, wherein: When the racket shaft is of a hollow structure, the inner diameter of the hollow part is not greater than φ5.0mm, and the length is 280 to 320mm. The racket shaft is made of carbon fiber composite material.

5. A carbon fiber badminton racket according to claim 1, wherein: When the racket shaft is of a solid structure, the racket shaft is manufactured by a three-time molding process, which consists of a solid cylinder one, a solid cylinder two and a stepped layer from the inside out. The solid cylinder one is composed of a cylinder made of carbon fiber material and a high molecular material filled inside; the diameter of the high molecular material filled inside the solid cylinder one is φ0.6 - φ1.2mm, and the diameter of the solid cylinder one is φ2.20mm - φ2.80mm.

6. A carbon fiber badminton racket according to claim 1, wherein: When the racket shaft is of a hollow structure, the racket shaft is manufactured by a two-time molding process, including a hollow cylinder and a stepped layer; The high molecular material filled inside is reinforced fiber resin.

7. A manufacturing method of a carbon fiber badminton racket using the one according to claim 1, wherein; When the racket shaft is of a solid structure, the following steps are taken to achieve: S1. Racket shaft manufacturing; S1.

1. Winding of solid cylinder one S1.

2. Winding of solid cylinder two S1.

3. Winding of stepped layer S2. Manufacturing of racket frame strip S3. Pre-forming of racket frame S4. Blank forming S5. Drilling and grinding of racket frame S6. Combining front sleeve and racket handle S7. Painting and beautifying processing of racket frame, racket shaft and front sleeve; S8. Making a racket.

8. The manufacturing method of a carbon fiber badminton racket according to claim 7, characterized in that ； S1. Racket shaft manufacturing: The shooting rod successively includes a stepped layer, a solid cylinder II, and a solid cylinder I from outside to inside. The solid cylinder II is tightly combined with the solid cylinder I. The stepped layer consists of a maximum outer diameter layer, a transition layer, and a minimum outer diameter layer. The maximum outer diameter layer and the transition layer are tightly joined on the solid cylinder II; S1.1, winding of the solid cylinder I (11)According to the size requirements of the solid cylinder I, take a carbon fiber composite prepreg containing epoxy resin that meets the thickness of the solid cylinder size, and cut it into a specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (12)Take a high-temperature resistant polymer material wire with a diameter of φ0.6 - φ1.2mm and a length of 450 - 550mm. Place the cut carbon fiber composite prepreg on the workbench, place the polymer material wire on the carbon fiber composite prepreg, and at the same time, align and tightly stick the edge of the prepreg with the polymer material wire, and then roll it into a solid cylinder shape by one turn; (13)Put the above-mentioned wound solid cylinder into a special molding die and fix the die; (14)Put the die into a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2°C, and the baking time is 30 - 60 minutes; (15)Remove the die from the heating device and place it in a cooling device for cooling. The cooling temperature is 5 - 15°C, and the cooling time is 5 - 10 minutes. Wait until the die cools to 45 - 55°C, open the die, and take out the formed solid cylinder I blank; (16)Grind the above-mentioned solid cylinder I blank to the specified size of φ2.20mm - φ2.80mm, that is, make the solid cylinder I; S1.2, winding of the solid cylinder II (21)According to the size requirements of the solid cylinder II, take a carbon fiber composite prepreg containing epoxy resin that meets the thickness of the solid cylinder II size, and cut it into a specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (22)Place the cut carbon fiber composite prepreg on the workbench, place the solid cylinder I on the carbon fiber composite prepreg, and at the same time, align and tightly stick the edge of the prepreg with the solid cylinder I, and then roll it into a solid cylinder shape by one turn; (23)Roll a special resin cloth on the outer layer of the above-mentioned wound solid cylinder shape. When rolling, it must be aligned and tightly stuck before proceeding; (24)Use a winding device to tightly wind an OPP film on the outer layer of the above-mentioned wound solid cylinder; (25)Put the solid cylinder part wound with the OPP film into a constant temperature oven for baking. The temperature in the oven is maintained at 150 ± 2°C, and the baking time is 30 - 60 minutes; (26)After baking, remove the outer OPP film after the solid cylinder part is cooled, which is the solid cylinder II blank; (27)Grind the above-mentioned solid cylinder II blank to the specified size of φ5.50mm - φ6.50mm. The residual of the special resin cloth on the outer layer of the ground solid cylinder-shaped part shall not exceed 10% of the volume of the original resin cloth, that is, make the solid cylinder II; S1.3, Step-layer winding (31)According to the dimensional requirements of the step layer, take a carbon fiber composite prepreg containing epoxy resin that meets the thickness of the step size, and cut it into the specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (32)Place the cut carbon fiber composite prepreg on the workbench, place the solid cylinder II on top of the carbon fiber composite prepreg as the core, align the corresponding step surfaces of the step layer, and at the same time align and tightly attach the edge of the prepreg to the straight line of the solid cylinder II, and then roll it one circle to form a stepped cylinder shape; (33)On the outermost diameter layer of the above-mentioned wound stepped cylinder shape, roll a special resin cloth, and it must be aligned and tightly attached during rolling; (34)Use a winding device to tightly wind an OPP film on the outer layer of the above-mentioned wound stepped cylinder shape; (35)Put the solid stepped cylinder part wound with OPP film into a constant temperature oven for baking, the temperature in the oven is maintained at 150 ± 2 °C, and the baking time is 30 - 60 minutes; (36)After the baked solid stepped cylinder part is cooled, remove the outer OPP film, which is the blank of the racket handle; (37)Grind the outermost diameter of the above-mentioned solid stepped racket handle to the specified size of φ6.2mm - φ7.2mm, and at the same time grind the stepped transition layer as required. The residual of the special resin cloth on the outer layer of the ground tubular part shall not exceed 10% of the original resin cloth volume. According to the dimensional requirements of the step, cut both ends of the ground tubular or solid cylinder part to the specified length of 280mm - 320mm, and then the badminton racket handle is made; S2. Manufacturing of racket frame strips S2.

1. Cut a lightweight non-woven fiber cloth evenly coated with a foaming resin layer into the specified size as required. Its width is determined according to the average perimeter of the racket frame cross-section, the width is 5 - 15mm, and the length is determined according to the perimeter of the racket frame, and the length is less than 780mm; S2.

2. Cut the carbon fiber composite prepreg containing epoxy resin into the specified size as required. Its length is determined according to the perimeter of the racket frame, and the length is less than 780mm. The width is controlled by weight, and the weight of the carbon fiber composite prepreg is controlled within 35 grams; by weight percentage, the weight ratio of the content of epoxy resin in the carbon fiber composite prepreg is 30% - 45%; S2.

3. Place the cut carbon fiber composite prepreg on the workbench, align one side of the prepreg with the marked straight line on the workbench, then place the cut lightweight non-woven fiber cloth coated with foaming resin on top of the carbon fiber composite prepreg, with the foaming resin layer of the lightweight non-woven fiber cloth facing up, and then roll it into a tube to obtain a carbon fiber composite prepreg tube part with foaming resin in the inner cavity; S3. Racket frame preforming S3.

1. Preform the rolled carbon fiber composite material prepreg tubular member on a preform mold to obtain a preformed racket frame. The preform mold is used to control the circumference of the racket frame. Connectors are inserted into two ports of the preformed racket frame, and then the connectors are connected to the upper end of the racket shaft. A carbon fiber composite material prepreg connecting patch is attached to the three-way joint where the preformed racket frame and the upper end of the racket shaft are connected and positioned. The connector, the racket frame, and the upper end of the racket shaft are joined and positioned to obtain a positioned racket preform. S3.2, removing the positioned racket preform from the preform mold, and attaching another carbon fiber composite material prepreg patch to the joint between the preform racket frame, the racket shaft and the joint as required to obtain a carbon fiber badminton racket preform; S4, Blank Forming S4.

1. Place the pre-shaped carbon fiber badminton racket preform into the racket forming mold, close and fasten the mold, and then move the mold into the heating device for heating. The heating temperature is 145 - 155 °C and the time is 30 - 60 minutes. The carbon fiber badminton racket preform cures and forms during the heating process. During the heating of the mold, the foaming resin in the inner cavity of the racket frame of the badminton racket preform continuously expands, forming a pressure of 5 kg / cm 2 ~12 kg / cm 2 in the inner cavity of the racket frame, and the racket frame is shaped along the inner cavity of the mold to form the racket frame shape; S4.

2. When the racket forming mold reaches the heating time, remove the racket forming mold from the heating device and place it in a cooling device for cooling. The cooling temperature is 5 to 15° C. and the cooling time is 5 to 10 minutes. When the mold is cooled to 45 to 55° C., move the racket forming mold to the workbench, open the mold, and take out the formed carbon fiber composite material badminton racket blank; S5. Drilling and polishing the frame S5.

1. After the badminton racket blank is formed, drilling holes into the racket frame of the badminton racket blank; S5.

2. Use EP series putty to fill the slight unevenness on the outer surface of the racket frame, and then put it in an oven at a temperature of 75-80 degrees Celsius for 2-3 hours. After the EP series putty is completely cured, use gauze paper to polish the surface of the racket blank to make it smooth; S6, front cover and handle combination S6.

1. Apply 0.5±0.1g of two-component adhesive to the lower end of the badminton racket shaft, and apply 0.5-1.0g of two-component adhesive to the joint hole between the handle and the racket shaft, and the joint surface between the front cover and the handle, respectively, to connect the front cover, the handle and the rough racket shaft together; S6.

2. Allow the two-component adhesive to cure at room temperature for 12 to 24 hours to firmly bond the front cover, the handle and the blank racket shaft; S6.

3. After the connection is firm, fix the countersunk screw at the junction of the front end of the handle and the rear end of the shaft to fix the handle and the shaft together, with the head of the countersunk screw flush with the surface of the handle; S7, frame, shaft, front cover painting and beautification processing After the front cover, the handle and the blank racket shaft are joined, the racket frame, the racket shaft and the front cover are painted and beautified according to the design requirements, and various colors of paint and transfer patterns of various shapes are sprayed on the racket frame, the racket shaft and the front cover; S8. Made into racket After the racket frame, racket shaft and front cover are painted and beautified, the wire protection nails are inserted into the holes of the racket frame, the rear cover is assembled on the rear end of the handle, the handle leather is wrapped around the outer surface of the handle, and then the racket strings are threaded through the racket frame according to the threading method and tightened on the badminton racket stringing machine to the required tension, thus making a badminton racket with excellent performance and beautiful appearance.

9. Using the manufacturing method of a carbon fiber badminton racket according to claim 1, It is characterized by: When the racket rod is a hollow structure, the following steps are taken to achieve: S1. Rack manufacturing; S1.1, Hollow Cylinder Rolling S1.2, Step layer rolling S2, manufacturing of racket frame strips; S3, frame pre-shaping; S4, blank forming; S5, drilling and polishing of racket frame; S6, combined front cover and handle; S7. Painting beautification processing of the racket frame, racket shaft and front sleeve; S8. Manufacturing the racket.

10. A manufacturing method of a carbon fiber badminton racket according to claim 9, It is characterized in that; When the racket shaft is of a hollow structure, the specific manufacturing method of the present invention is realized by the following steps: S1. Racket shaft manufacturing: The racket shaft includes a stepped layer and a hollow cylinder from outside to inside in sequence. The stepped layer is composed of a maximum outer diameter layer, a transition layer and a minimum outer diameter layer. The maximum outer diameter layer and the transition layer are tightly joined to the hollow cylinder; S1.

1. Rolling of the hollow cylinder (11) According to the size requirements of the hollow cylinder, take a carbon fiber composite prepreg containing epoxy resin with a thickness meeting the size requirements of the hollow cylinder, and cut it into the specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (12) Place the cut carbon fiber composite prepreg on the workbench, place the core on the carbon fiber composite prepreg, and at the same time align the edge of the prepreg with the marked straight line of the core and stick it tightly, then roll it into a tubular cylinder shape; (13) Roll a special resin cloth on the outer layer of the above-mentioned rolled tubular cylinder shape. When rolling, it must be aligned and stuck tightly before proceeding; (14) Use a winding device to tightly wind a layer of OPP film on the outer layer of the above-mentioned rolled tubular cylinder; (15) Put the tubular part wound with OPP film into a constant temperature oven for baking. The temperature in the oven is kept at 150 ± 2 °C, and the baking time is 30 - 60 minutes; (16) Take out the core from the baked tubular part and remove the outer OPP film; it is the blank of the hollow cylinder; (17) Grind the above-mentioned hollow cylinder blank to the specified size of φ5.50mm - φ6.50mm. The residual of the special resin cloth on the outer layer of the ground hollow cylinder shall not exceed 10% of the original resin cloth volume, that is, the hollow cylinder is made; S1.

2. Rolling of the stepped layer (21) According to the size requirements of the stepped layer, take a carbon fiber composite prepreg containing epoxy resin with a thickness meeting the stepped size requirements, and cut it into the specified size as required. By weight percentage, the content of epoxy resin in the carbon fiber composite prepreg is 24% - 36%; (22) Place the cut carbon fiber composite prepreg on the workbench, place the hollow cylinder as the core on the carbon fiber composite prepreg, align the stepped surface corresponding to the stepped transition layer, and at the same time align the edge of the prepreg with the hollow or solid cylinder and stick it tightly, then roll it one circle into a stepped cylinder shape; (23) Roll a special resin cloth on the maximum outer diameter layer of the above-mentioned rolled stepped cylinder shape. When rolling, it must be aligned and stuck tightly before proceeding; (24) Insert an iron core into the hollow cylinder and fix it firmly. The iron core and the hollow cylinder adopt an interference fit; (25) Use a winding device to tightly wind a layer of OPP film on the outer layer of the above-mentioned rolled stepped cylinder; (26) Put the stepped cylinder part wound with OPP film into a constant temperature oven for baking. The temperature in the oven is kept at 150 ± 2 °C, and the baking time is 30 - 60 minutes; (27) Take out the core from the baked stepped cylinder part tubular part and remove the outer OPP film, which is the racket shaft blank; (28)Grind the maximum outer diameter of the above stepped cylinder to the specified size of φ6.2mm - φ7.2mm. At the same time, grind the stepped transition layer as required. The residual of the special resin cloth on the outer layer of the ground tubular part shall not exceed 10% of the original resin cloth volume. After cutting both ends of the ground tubular or solid cylinder part to the specified length of 280mm - 320mm according to the stepped size requirements, the badminton racket shaft is made; S2. Manufacturing of racket frame strips S2.

1. Cut the light non-woven fiber cloth evenly coated with a foaming resin layer on one side into the specified size as required. Its width is determined according to the average perimeter of the racket frame section, with a width of 5 - 15mm, and its length is determined according to the racket frame perimeter, with a length less than 780mm; S2.

2. Cut the carbon fiber composite material prepreg containing epoxy resin into the specified size as required. Its length is determined according to the racket frame perimeter, with a length less than 780mm, and its width is controlled by weight. The weight of the carbon fiber composite material prepreg is controlled within 35 grams; by weight percentage, the weight ratio of epoxy resin in the carbon fiber composite material prepreg is 30% - 45%; S2.

3. Place the cut carbon fiber composite material prepreg on the workbench, align one side of the prepreg with the marked straight line on the workbench, then place the cut light non-woven fiber cloth on top of the carbon fiber composite material prepreg with the foaming resin layer facing up, and then roll it into a tube to obtain a carbon fiber composite material prepreg tubular part with foaming resin in the inner cavity; S3. Pre-forming of racket frame S3.

1. Pre-form the rolled carbon fiber composite material prepreg tubular part on the pre-forming mold to obtain a pre-formed racket frame. The pre-forming mold is used to control the racket frame perimeter. Insert joints at both ports of the pre-formed racket frame, and then connect the joints to the upper end of the racket shaft; paste a carbon fiber composite material prepreg connection patch at the three-way joint where the pre-formed racket frame is joined to the upper end of the racket shaft to position the joint, racket frame, and upper end of the racket shaft, and obtain a well-positioned racket pre-form; S3.

2. Remove the well-positioned racket pre-form from the pre-forming mold. According to requirements, paste another carbon fiber composite material prepreg connection patch at the joint of the pre-formed racket frame, racket shaft, and joint to obtain a carbon fiber badminton racket pre-form; S4. Blank forming S4.

1. Place the pre-shaped carbon fiber badminton racket preform into the racket forming mold, close and fasten the mold, and then move the mold into the heating device for heating at a temperature of 145 - 155 °C for 30 - 60 minutes; the carbon fiber badminton racket preform cures and forms during the heating process. During the heating of the mold, the foaming resin in the inner cavity of the racket frame of the badminton racket preform continuously expands, forming a pressure of 5 kg / cm 2 ~12 kg / cm 2 in the inner cavity of the racket frame, and the racket frame is shaped along the inner cavity of the mold to form the racket frame shape; S4.

2. When the racket forming mold reaches the heating time, remove the racket forming mold from the heating device and place it in the cooling device for cooling. The cooling temperature is 5 - 15°C, and the cooling time is 5 - 10 minutes. Wait until the mold cools to 45 - 55°C, then move the racket forming mold to the workbench, open the mold, and take out the formed carbon fiber composite badminton racket blank; S5. Drilling and grinding of racket frame S5.

1. After forming the badminton racket blank, drill holes in the racket frame of the badminton racket blank; S5.

2. Fill the slight unevenness on the outer surface of the racket frame with EP series putty, then put it in an oven at a temperature of 75 - 80°C for 2 - 3 hours. After the EP series putty is completely cured, use sandpaper to polish the surface of the racket blank flat; S6. Assemble the front sleeve and racket handle S6.

1. Apply 0.5 ± 0.1 g of two-component adhesive to the lower end of the racket shaft of the badminton racket blank. At the same time, apply 0.5 - 1.0 g of two-component adhesive to the joint hole between the handle and the racket shaft and on the joint surface between the front sleeve and the handle, and connect the front sleeve, the handle and the racket blank shaft together; S6.

2. Cure the two-component adhesive at room temperature for 12 - 24 hours to firmly join the front sleeve, the handle and the racket blank shaft; S6.

3. After firm joining, fix the countersunk screw at the joint of the front end of the handle and the rear end of the racket shaft to fixedly connect the handle and the racket shaft, with the head of the countersunk screw flush with the surface of the handle; S7. Painting and beautifying processing of the racket frame, racket shaft and front sleeve After the front sleeve, the handle and the racket blank shaft are joined, carry out painting and beautifying processing on the racket frame, racket shaft and front sleeve according to the design requirements, and spray various colors of paint and transfer various shaped transfer patterns on the racket frame, racket shaft and front sleeve; S8. Manufacture the racket After the painting and beautifying processing of the racket frame, racket shaft and front sleeve, insert the grommets into the holes of the racket frame, assemble the rear sleeve at the rear end of the handle, wrap the handle grip on the outer surface of the handle, and then thread the strings through the racket frame according to the stringing method and tighten the strings to the required tension on the badminton racket stringing machine to manufacture a badminton racket with excellent performance and beautiful appearance.

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