An artificial feather sheet and a method of manufacturing the same, and an artificial shuttlecock

Abstract

The present application belongs to the technical field of sports goods, and relates to an artificial feather piece, a preparation method thereof and an artificial shuttlecock. The artificial feather piece comprises an inner feather piece, an outer feather piece and a feather rod clamped at one end between the inner feather piece and the outer feather piece. The inner feather piece and the outer feather piece are both cut from a hot air non-woven material web made of low-melting-point fibers through web formation and hot air reinforcement. The fiber diameters of the inner feather piece and the outer feather piece are different, the average pore size of the outer feather piece is larger than that of the inner feather piece, and the fiber arrangement directions of the inner feather piece and the outer feather piece are both perpendicular to the length direction of the feather rod. The preparation method comprises the following steps: clamping the one end of the feather rod between two hot air non-woven material webs, and stamping and hot pressing to obtain the artificial feather piece. The artificial shuttlecock comprises a ball head and 16 artificial feather pieces, and the end of the feather rod away from the inner and outer feather pieces is inserted into the ball head. The artificial shuttlecock has obvious improvement in flight performance and structural reliability.

Description

Technical Field

[0001] This invention belongs to the field of sporting goods technology, and relates to an artificial feather piece, its preparation method, and an artificial shuttlecock. Background Technology

[0002] Natural badminton shuttlecocks are currently the mainstream product in badminton. Their feathers are mainly made of natural goose or duck feathers. With the symmetrical distribution of barbs along the shaft and the hook-like interlocking barbules forming a double-sided heterogeneous structure (one side is a dense, mesh-like surface, and the other side is a sparse surface with small tubular gaps), they can achieve directional control of airflow. By controlling the airflow at the tail, they can generate appropriate pressure drag. When the airflow permeability is low, a "stagnant" air area will form in the feather area, which is prone to interacting with the high-speed airflow outside to generate an unstable wake. When the airflow permeability is high, the wake will be accelerated. Although this may reduce turbulence, it will increase the negative pressure and pressure drag at the tail. The double-sided heterogeneous structure of natural feathers can balance this contradiction, thus giving them excellent flight trajectory stability, which is highly favored by athletes.

[0003] However, natural badminton shuttlecocks rely heavily on natural poultry feathers. In recent years, the decline in goose and duck farming has led to a tightening supply of raw feather materials, directly driving up the production cost of shuttlecocks and placing a heavy economic burden on consumers who regularly participate in badminton. At the same time, natural feathers are fragile and easily damaged by the huge impact of a hit. Damaged feathers severely disrupt the shuttlecock's flight balance, causing a sharp decline in flight performance. This necessitates frequent shuttlecock replacements during play, interrupting the rhythm of the game, affecting the experience, and wasting natural resources. Therefore, developing high-performance artificial shuttlecocks that can replace natural ones has become an urgent need for the industry.

[0004] Early alternatives often involved injection-molded nylon shuttlecocks. These shuttlecocks had their skirts molded in one piece and inserted into the head using an injection molding process. However, injection-molded plastic skirts are often soft and heavy, lacking rigidity. Under the immense impact of a hit and the air resistance during high-speed flight, they are prone to significant shrinkage and deformation, altering their shape and reducing air resistance. This resulted in nylon shuttlecocks having higher flight speeds and slower speed decay. More importantly, the heavier plastic skirt shifts the shuttlecock's center of gravity towards the skirt, deviating from the range required for stable flight. This leads to tumbling or wobbling during flight, resulting in significantly less flight stability compared to natural badminton shuttlecocks.

[0005] Carbon fiber shuttlecocks represent an improvement over injection-molded nylon shuttlecocks, but the issue of their high flight speed remains unresolved. Their blades are made of polyethylene foam, a lightweight and small material that limits their durability, making them prone to damage after repeated hits. Furthermore, while the carbon fiber shafts offer good rigidity and hardness, making them resistant to bending, they pose a safety hazard. When the foam material is damaged, the sharp tips of the carbon fiber shafts become exposed, potentially injuring the user from the high-speed flight of the shuttlecock.

[0006] Patent application CN119868905A discloses a lightweight, bend-resistant biomimetic feather, its preparation method, and its application. It optimizes the performance of artificial badminton shuttlecocks through biomimetic design and nonwoven material technology. This lightweight, bend-resistant biomimetic feather comprises a first feather, a second feather, and a shaft. The feather is made from a nonwoven material mixed with PET / PE, which is carded into a web, hot-air reinforced, hot-rolled, and cut to the shape of natural goose feathers. The shaft is made from a nonwoven material mixed with PET and low-melting-point 4080 fiber, which is carded, pre-needled, layered, hot-pressed (divided into different areal density areas), and cut. The three components are glued together, and 16 of these feathers can be detachably attached to the head of the shuttlecock to form an artificial badminton shuttlecock. This patent application uses lightweight nonwoven materials to control the total weight of the feathers and improves rigidity through differentiated areal density design of the shaft, optimizing weight balance and structural stability. Furthermore, the blades are reinforced by hot air and hot-rolled to enhance bending resistance, and the shaft uses composite nonwoven sheets without sharp tips, improving durability and safety. However, this patent application still has key shortcomings: the bending stiffness of the shaft made from composite nonwoven sheets is still limited, significantly different from natural feather shafts; while ensuring the overall weight of the shuttlecock doesn't exceed the limit and the center of gravity is biased towards the head, the maximum total areal density of the blades is limited, resulting in insufficient impact resistance; the first and second blades use the same fiber specifications, and adjusting the areal density combination alone is insufficient to create an effective pore size gradient, failing to mimic the structure of natural feathers to achieve good airflow control. Summary of the Invention

[0007] The purpose of this invention is to solve the problems existing in the prior art and to provide an artificial feather piece, its preparation method, and an artificial shuttlecock.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] An artificial feather includes an inner feather, an outer feather, and a quill held between the two at one end. Both the inner and outer feathers are cut from a hot-air nonwoven fiber web. The hot-air nonwoven fiber web is made of low-melting-point fibers that are combed into a web and reinforced with hot air. The fibers in the inner feather have the same diameter, denoted as d1, and the fibers in the outer feather have the same diameter, denoted as d2. d1≠d2.

[0010] The average aperture of the outer barbs is 3 to 11 times that of the average aperture of the inner barbs;

[0011] The fibers in both the inner and outer vanes are arranged perpendicular to the length of the quill.

[0012] The vanes of natural feathers are composed of curved barbs symmetrically distributed at approximately a 30° angle along both sides of the shaft. Each barb extends barbules from both ends on one side of the vane. These barbules interlock through hook-like structures, forming a dense network that constitutes the compact surface of the vane. On the opposite side, slightly curved barbules are arranged directly to form a sparse surface. Small tubular gaps exist between adjacent barbules on this surface. These inclined channels provide directional flow paths for airflow. When airflow moves from the sparse surface to the compact surface, the airflow cannot directly penetrate the vane due to the obstruction of the compact surface. Instead, it is forced to flow out orderly along the tubular channels, significantly reducing airflow permeability and turbulence generation. This bifacial heterogeneous structure effectively maintains the integrity of the vane morphology by regulating airflow direction and speed. Especially in badminton, it guides airflow along a specific path to reduce air resistance fluctuations. Simultaneously, by reducing airflow penetration, it enhances anti-interference capabilities, thereby significantly improving the trajectory stability of the shuttlecock.

[0013] The inner and outer feathers of this invention use fibers of the same specification, but the diameters of the two are different, making them structurally closer to natural feathers.

[0014] In the manufacturing process of a natural badminton shuttlecock, the tightly packed surfaces of the 16 feathers all face inwards, while the sparser surfaces face outwards. Therefore, this invention controls the average aperture of the outer feathers to be 3 to 11 times that of the inner feathers. This allows for a better simulation of the natural feathers' control over airflow through the difference in aperture between the inner and outer feathers. When the shuttlecock is in flight, the oncoming airflow more easily penetrates the sparse outer feathers and flows out through their oriented pores. This airflow control mitigates the severe impact of the oncoming airflow on the feathers, reduces flight sway, and improves flight stability, resulting in a smoother flight for the shuttlecock. If the ratio of the average aperture of the outer feathers to that of the inner feathers is less than 3, the apertures are too close, making it impossible to better simulate the structure of natural feathers and achieve good airflow control. If the ratio is greater than 11, the aperture difference is too large, and the outer feathers, due to fewer fiber bonding points, have a loose structure, resulting in poor mechanical properties, insufficient durability, and susceptibility to damage from impacts.

[0015] The fiber arrangement direction affects the arrangement direction of the pores inside the feather vane. For example, if the fibers are arranged parallel to the length of the quill, then the pores inside the feather vane (mainly the pores between fibers) will also be more oriented parallel to the length of the quill. This invention controls the fiber arrangement direction in both the inner and outer feather vanes to be perpendicular to the length of the quill. It can be considered that the direction of the internal channel pores is also mostly perpendicular to the length of the quill. This structure facilitates airflow entering from the more permeable outer feather vane side, while preventing it from completely passing through the less permeable inner feather vane side, and simultaneously exiting from the oriented pores of the outer feather vane.

[0016] Airflow primarily refers to the permeability of gas penetrating hot air nonwoven materials. The core factor affecting permeability is pore size, followed by porosity. Porosity is the percentage of pore volume within a material's total volume, while pore size is the characteristic diameter of the pore channels. According to fluid mechanics principles, airflow resistance is inversely proportional to the fourth power of the channel radius. Even with high porosity, small pore size will still result in low permeability. Taking a specific areal density as an example, the main pore size range formed by fine fibers (15 μm in diameter) is 40–130 μm, while that formed by coarse fibers (30 μm in diameter) is 100–500 μm. The porosity range of the feathers in this invention is 82%–95%.

[0017] As a preferred technical solution:

[0018] As described above, the artificial feather has d1 and d2 values ​​ranging from 12 to 36 μm, and the sum of the areal densities of the inner and outer vanes (i.e., the areal density of the feather vane) is 90 to 150 g / m². 2 The total mass of the inner and outer barbs is 0.0435~0.0720g.

[0019] Adjusting d1, d2, the areal density of the inner and outer barbs can control the average aperture of the outer barbs and the average aperture of the inner barbs, making the average aperture of the outer barbs 3 to 15 times that of the inner barbs.

[0020] Parameters affecting pore size include: fiber diameter (most critical, finer fibers result in smaller pores), fiber cross-sectional shape (circular fibers create regular pores, irregular cross-sections create more irregular pores), fiber length and crimp (long fibers create uniform pores, highly crimped fibers increase pore size), web forming process (random webs have uniform pore size, parallel webs have elongated shapes), consolidation process (hot air consolidation creates large-pore, high-porosity structures), areal density (higher areal density results in smaller pores), and thickness (greater thickness results in larger pores). Parameters affecting porosity include: fiber fineness, fiber length and crimp, fiber cross-sectional shape and thermal shrinkage, fiber mixing ratio, hot air temperature, and hot air treatment time.

[0021] The reason why this invention controls the areal density of the pinnae to be 82.8~155.25 g / m³ is that... 2 The considerations are center of gravity and durability. While excessively high areal density in the feather design can improve durability, it significantly increases the weight of the artificial feathers. Assuming a single artificial feather adds 0.01 grams, a shuttlecock containing 16 artificial feathers will increase in weight by 0.16 grams. This not only directly increases the total weight of the shuttlecock but, more importantly, shifts the center of gravity towards the skirt. To correct this downward shift, a heavier head must be used for weight distribution, potentially bringing the total weight of the artificial shuttlecock close to or exceeding the international standard limit of 5.5 grams. Even within this limit, the increased weight will significantly alter the flight trajectory of the artificial shuttlecock, resulting in a marked difference from the flight characteristics of a natural shuttlecock.

[0022] Conversely, if the areal density of the feathers is designed to be too low, it will result in sparse fiber distribution and a reduced number of bonding points, directly weakening the mechanical strength and impact resistance of the feather area. At the same time, insufficient fiber support will make the feathers soft and easily deformed, making them more prone to irreversible deformation during high-speed flight or impacts, further affecting flight stability. Therefore, the control of the areal density of the feathers requires a precise balance between impact resistance, weight balance, and flight performance.

[0023] As described above, in an artificial feather, the edge regions of the inner and outer feathers are joined by thermo-pressing.

[0024] The hot-press bonding method used in this invention has two main advantages: First, it utilizes the inherent heat-melting properties of low-melting-point fibers to generate adhesion, eliminating the need for chemical adhesives and reducing production costs; second, it eliminates the need for adhesives, allowing the saved weight to be used to increase the areal density of the feathers, thereby further improving their impact resistance (the higher the areal density, the more fibers and fiber bonding points there are, resulting in better impact resistance) and stiffness (increasing stiffness can effectively prevent feathers from bending and turning).

[0025] Meanwhile, during the production of artificial feathers, the size of the hot-pressed bonding area around the feather also affects the durability. The width of the annular hot-pressed bonding area in this invention ranges from 1.5 to 2 mm.

[0026] If the edges of the inner and outer vanes are joined by adhesive, the glue will increase the weight of the vanes (approximately 0.020~0.035g), causing the center of gravity to shift upwards and affecting flight stability. To ensure excellent flight stability, the areal density of the vanes needs to be controlled at 82.8g / m³. 2 This will damage its durability.

[0027] As described above, the artificial feather has a low-melting-point fiber that is a PP / PE bicomponent core-sheath composite fiber, a PE sheath material, and a sheath thickness of 2~10μm.

[0028] This invention selects PP / PE bicomponent core-sheath composite fiber as the raw material primarily due to its low density. Under the condition of maintaining consistent key parameters such as areal density and fiber diameter, feathers prepared using PP / PE bicomponent core-sheath composite fiber exhibit a higher fiber filling density per unit area and a corresponding increase in the number of inter-fiber bonding points. This structural characteristic directly improves the material's mechanical properties, resulting in higher stiffness and superior impact resistance. In contrast, if other low-melting-point fibers are used under the same areal density conditions, the higher density inevitably leads to a decrease in the number of fibers per unit area, resulting in a decline in the material's mechanical properties and insufficient stiffness.

[0029] The process parameters for combing and forming the web of the artificial feather as described above include: feeding speed 0.52~0.74 r / min, cylinder speed 280~320 r / min, doffer speed 6.83~7.45 r / min, randomization speed 5.64~6.56 r / min, and spooling speed 8.65~12.14 r / min;

[0030] The process parameters for hot air reinforcement include: hot air temperature is 1.14 to 1.25 times the melting point of the low-melting-point fiber leather, and hot air treatment time is 90 to 120 seconds.

[0031] As described above, an artificial feather has a spear-shaped shaft consisting of a shaft and a head, with the head used for insertion into a ball. The shaft is 0.55-1.08 mm thick. The shaft has a width that increases from the end furthest from the head to the end closest to the head, with a minimum width of 0.4-0.6 mm and a maximum width of 1.3-1.5 mm. The shaft is 63-64 mm long, the head is 9-14 mm long, and the head has a maximum width of 2-3.5 mm.

[0032] The shaft's shape is designed to better insert and secure the shuttlecock inside the head, while also increasing the weight of each feather embedded within the head, thus shifting the center of gravity towards the head to some extent. This shaft, with its excellent bending resistance, allows the shuttlecock to resist deformation during impact and quickly recover from deformation. Combined with the thickened design at the bottom, it further stabilizes the shuttlecock's flight and solves the problem of wobbling.

[0033] As described above, the artificial feather shaft consists of two nonwoven fabric layers and a carbon fiber reinforced resin matrix composite plate sandwiched between them;

[0034] The areal density of nonwoven fabric is 50~100 g / m². 2 ;

[0035] In carbon fiber reinforced resin matrix composite plates, the carbon fibers are arranged parallel to the length direction of the fletching shaft to improve its bending resistance. The thickness of the carbon fiber reinforced resin matrix composite plates is 0.35~0.85mm, and the areal density is 550~650g / m³. 2 .

[0036] There are two reasons for covering the surface of the feather shaft with non-woven fabric in this invention. First, carbon fiber is black, and covering it with non-woven fabric can make the feather shaft appear white, which is closer to the color of the natural feather shaft. Second, the surface of carbon fiber is smooth, and covering it with non-woven fabric can increase its surface roughness to adapt to the subsequent stringing process in feather making. Otherwise, if the surface of the feather shaft is too smooth, the string will easily fall off and cannot be fixed in the required position, and thus the stringing process cannot be completed.

[0037] The artificial feather fabric described above is obtained by carding low-melting-point 4080 fibers into a web and then pre-reinforcing it with needle punching. The carding process parameters include: feeding speed 0.52~0.74 r / min, cylinder speed 280~320 r / min, doffer speed 6.83~7.45 r / min, randomization speed 5.64~6.56 r / min, and winding speed 8.65~12.14 r / min. The needle punching pre-reinforcing process parameters include: needle density 2250 needles / m, needle punching frequency 160~240 r / min, web output speed 0.8~1.5 m / min, needle punching depth 1~5 mm, and step size 2~6 mm / needle.

[0038] Carbon fiber reinforced resin matrix composite panels are obtained by laminating two layers of unidirectional carbon fiber prepreg and then hot-pressing and curing them; wherein the thickness of the unidirectional carbon fiber prepreg is 0.2~0.5mm and the areal density is 200~300g / m³. 2 ;

[0039] The preparation process of the feather shaft is as follows: a carbon fiber reinforced resin matrix composite plate is sandwiched between two pieces of non-woven fabric and hot-pressed together, and then cut to obtain the feather shaft; the process parameters of hot-pressing include: hot-pressing temperature is 1.45~1.82 times the melting point of the low melting point 4080 fiber lining, hot-pressing time is 200~300s, and hot-pressing pressure is 0.5~2MPa.

[0040] The present invention also provides a method for preparing an artificial feather as described in any of the preceding claims, wherein one end of the feather shaft is clamped between two hot-air nonwoven fiber webs, and the two hot-air nonwoven fiber webs are punched and hot-pressed to obtain the artificial feather.

[0041] As a preferred technical solution:

[0042] As described above, stamping and hot pressing use a set of dies, which includes an upper die and a lower die;

[0043] The upper surface of the lower die is a horizontal plane, on which at least one pair of strip grooves and annular grooves are provided. The annular groove surrounds one end of the same pair of strip grooves. The strip grooves are used to load feather shafts. The shape and size of the inner edge of the annular groove are the same as those of the inner and outer feathers.

[0044] The lower surface of the upper mold is provided with a hot press cylinder corresponding to each annular groove. The lower end face of the hot press cylinder is a horizontal plane. The orthographic projection of the outer edge of the hot press cylinder completely coincides with the orthographic projection of the inner edge of the corresponding annular groove. The outer edge of the hot press cylinder extends downward to form a cutting blade. The cutting blade is provided with a notch to prevent cutting the feather rod. The height of the cutting blade on the hot press cylinder is equal to the depth of its corresponding annular groove. The thickness of the cutting blade on the hot press cylinder is not higher than the width of its corresponding annular groove.

[0045] The upper mold has a heating function.

[0046] As described above, the upper surface of the lower mold is rectangular, with a pair of opposite sides denoted as side a and side b, and the direction parallel to side a and side b is denoted as direction X.

[0047] There are 2n pairs of strip grooves and annular grooves, where n is a positive integer;

[0048] n pairs of strip grooves and annular grooves are arranged at intervals along the X direction, with the end of the strip groove not surrounded by the annular groove flush with side a. In addition, n pairs of strip grooves and annular grooves are arranged at intervals along the X direction, with the end of the strip groove not surrounded by the annular groove flush with side b.

[0049] As described above, the lower mold has two rocker arms parallel to the direction X on both sides. Each rocker arm has n connecting rods fixed vertically. The rocker arm and the n connecting rods form a comb-shaped structure. Each connecting rod has a clamping port at its free end for clamping the feather shaft.

[0050] One rocker arm is located near side a, and its n connecting rods are used to place n feather shafts into n strip-shaped grooves. Another rocker arm is located near side b, and its n connecting rods are used to place n feather shafts into another n strip-shaped grooves.

[0051] The hot pressing mold of this invention has significant advantages over existing technologies (such as patent application CN117621515A): Existing technologies install multiple sets of forming molds on two conveyor belts, and complete the meshing and stamping through an internal adjustment mechanism, which is complex, prone to failure, and cumbersome to maintain. In contrast, the mold structure of this invention is simple, with only grooves for the preparation of artificial feathers and a hot pressing cylinder set in the upper and lower molds. It does not require complex internal mechanisms, and multiple products can be prepared by corresponding hot pressing of the upper and lower molds, making it easy to inspect and maintain. At the same time, existing technologies conceal the feather shafts inside the mold, resulting in a complex structure. This invention adopts an external method, using a comb-shaped rocker and connecting rod to hold the feather shafts for placement and removal, simplifying the mold design, reducing the failure rate, and improving maintenance efficiency and convenience.

[0052] The present invention also provides an artificial badminton shuttlecock, comprising a shuttlecock head and 16 artificial feathers as described in any of the preceding claims, wherein the ends of the artificial feathers away from the inner and outer vanes are inserted into the shuttlecock head.

[0053] To achieve proper center of gravity adjustment, a composite cork head weighing 2.35~2.50g is selected for the shuttlecock head. Its weight matches the weight of the 16 artificial feathers, especially the weight of the feather section, to ensure the stability of the shuttlecock's center of gravity.

[0054] Beneficial effects:

[0055] (1) By designing inner and outer feathers with different diameter fibers and optimizing fiber arrangement direction, this invention can accurately simulate the double-sided heterogeneous structure of natural feathers, effectively regulate the airflow state, reduce swaying and air resistance fluctuations during flight, and reasonably control the weight and center of gravity distribution of the feathers to avoid center of gravity shift or feather deformation, making the flight trajectory of artificial feathers and corresponding artificial shuttlecocks closer to that of natural shuttlecocks, and significantly improving flight stability.

[0056] (2) The present invention selects fiber materials with specific properties as raw materials for feathers and achieves the connection of inner and outer feathers through hot pressing bonding technology. It does not rely on chemical glue, which reduces the performance impact caused by extra weight and allows the saved weight to be used to optimize the feather structure, improve the stiffness and mechanical strength of the feathers. At the same time, the feather shaft adopts a composite structure design, which enhances the bending resistance, making the product less prone to bending and damage when subjected to impact or high-speed flight, and greatly improving the impact resistance and structural reliability.

[0057] (3) The present invention uses hot pressing bonding process to replace traditional glue bonding, directly utilizes the properties of the raw materials to achieve connection, saves the cost of glue purchase and use, simplifies the production process, and at the same time, with special molds and feeding structure, improves production efficiency and product specification consistency, making large-scale production more convenient, and the production process is more environmentally friendly, without the need to deal with glue-related environmental issues.

[0058] (4) This invention comprehensively optimizes the structure, materials and processes of artificial feathers, so that the core performance of the product is highly compatible with that of natural badminton shuttlecocks. The assembly of artificial badminton shuttlecocks can be completed without adjusting the existing shuttlecock manufacturing process. Moreover, the product performance meets industry standards and can be adapted to various badminton sports scenarios, effectively meeting the market demand for high-quality artificial badminton shuttlecocks. Attached Figure Description

[0059] Figure 1 This is a schematic diagram of the upper mold structure;

[0060] Figure 2 This is a schematic diagram of the hot press cylinder.

[0061] Figure 3 This is a schematic diagram of the lower mold structure;

[0062] Figure 4 Schematic diagrams of strip grooves and annular grooves;

[0063] Figure 5 This is a schematic diagram of the feather shaft;

[0064] Figure 6 This is a schematic diagram of the structure of an artificial feather.

[0065] Figure 7 A schematic diagram of the structure of an artificial badminton shuttlecock;

[0066] Figure 8 This is a schematic diagram showing the arrangement of fibers in the inner and outer vanes; where line AB represents the length direction of the quill.

[0067] Figures 1-8 In the middle, 1-shaft, 10-spear shaft, 11-spear head, 2-upper mold, 20-hot press cylinder, 21-cutting blade, 22-notch, 3-lower mold, 30-rocker, 31-strip groove, 32-annular groove, 34-connecting rod, 4-feather, 41-inner feather, 42-outer feather, 5-ball head, 6-fiber in the inner or outer feather. Detailed Implementation

[0068] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0069] The test methods for the relevant performance indicators in the following embodiments or comparative examples are as follows:

[0070] Melting point: The differential scanning calorimetry (DSC) method in section 5.3 of GB / T 14190-2017 was used for testing. Specifically, after vacuum drying the sample at 80℃ for 12 hours, 6 mg of the sample was weighed and placed in a TA Q-20 differential scanning calorimeter. Under a nitrogen atmosphere, the sample was first heated to 280℃ at a heating rate of 20℃ / min and held for 3 minutes to eliminate thermal history. Then, the sample was cooled to 40℃ at a heating rate of 10℃ / min and held for 3 minutes. Finally, the sample was heated to 280℃ at a heating rate of 10℃ / min. The thermal curves of the cooling and the second heating were recorded. The peak value formed by the cooling on the thermal curve is the crystallization temperature, and the peak value formed by the second heating is the melting point.

[0071] Transverse tensile strength and longitudinal tensile strength: tested according to GB / T3356-2014 "Test Method for Tensile Properties of Fiber Reinforced Plastics", with a loading speed of 2 mm / min.

[0072] Bending strength: Tested according to GB / T 1449-2005 "Test method for bending properties of fiber reinforced plastics", with a loading speed of 5 mm / min.

[0073] Transverse strength, longitudinal strength, transverse elongation, and longitudinal elongation: tested according to GB / T 24218.3-2010 "Textiles - Test methods for nonwoven fabrics - Part 3: Determination of breaking strength and elongation at break (strip method)".

[0074] Transverse / longitudinal bending stiffness: Tested according to GB / T 18318.1-2009 "Textiles - Determination of bending properties of fabrics - Part 1: Inclined plane method".

[0075] Air permeability: Tested according to GB / T 5453-1997 "Textiles - Determination of Air Permeability of Fabrics", with a pressure difference of 200 Pa and a test area of ​​20 cm². 2 .

[0076] Rotation speed: The rotation speed of the badminton shuttlecock was tested using a YMQ-FD type badminton wind tunnel machine.

[0077] Flight stability, durability, and hitting feel: Referring to the GB / T 11881-2006 "Badminton" evaluation standard, eight professionals with more than five years of badminton experience (including two amateur tournament referees and six senior coaches) were invited to conduct a two-hour continuous live-fire test on various badminton shuttlecocks, covering scenarios such as high clears, smashes, flat drives, net shots, and high-level rallies. After the test, scores were given out out of 10 for three core performance aspects: flight stability (focusing on flight trajectory deviation and consistency of landing point), durability (focusing on the degree of feather damage and shuttlecock head deformation), and hitting feel (focusing on the elasticity of the racket and ease of control). The scoring rule was to remove the highest and lowest scores and take the average of the remaining six professional scores as the final evaluation result.

[0078] In the following embodiments, the stamping and hot pressing in step (5) use a set of dies, such as Figure 1 and Figure 3 As shown, the mold includes an upper mold 2 and a lower mold 3;

[0079] like Figure 3 and Figure 4 As shown, the upper surface of the lower mold 3 is a horizontal surface, on which at least one pair of strip grooves 31 and annular grooves 32 are provided. The annular groove 32 surrounds one end of its pair of strip grooves 31. The strip grooves 31 are used to load feather shafts. The shape and size of the inner edge of the annular groove 32 are the same as those of the inner and outer feathers. The upper surface of the lower mold 3 is rectangular, with one pair of opposite sides denoted as side a and side b. The direction parallel to side a and side b is denoted as direction X. There are 2n pairs of strip grooves 31 and annular grooves 32, where n is a positive integer. The n pairs of strip grooves 31 and annular grooves 32 are arranged along the direction X with spacing, and the end of the strip groove 31 not surrounded by the annular groove 32 is flush with side a. The other n pairs of strip grooves 31 and annular grooves 32 are arranged along the direction X with spacing. The grooves 31 and annular grooves 32 are arranged at intervals along the X direction, and the end of the strip groove 31 not surrounded by the annular groove 32 is flush with the edge b; the lower mold 3 has two rocker arms 30 parallel to the X direction on both sides, and each rocker arm 30 has n connecting rods 34 vertically fixed on it. The rocker arm 30 and the n connecting rods 34 on it form a comb-shaped structure. The free end of each connecting rod 34 has a clamping port for clamping feather shafts; one rocker arm 30 is close to the edge a, and the n connecting rods 34 on it are used to place the n feather shafts in the n strip grooves 31. The other rocker arm 30 is close to the edge b, and the n connecting rods 34 on it are used to place the n feather shafts in the other n strip grooves 31.

[0080] like Figure 1 and Figure 2As shown, the lower surface of the upper mold 2 is provided with a hot press cylinder 20 corresponding to each annular groove 32. The lower end face of the hot press cylinder 20 is a horizontal plane. The orthographic projection of the outer edge of the hot press cylinder 20 completely coincides with the orthographic projection of the inner edge of the corresponding annular groove 32. The outer edge of the hot press cylinder 20 extends downward to form a cutting blade 21. The cutting blade 21 is provided with a notch 22 for preventing the cutting of the feather rod. The height of the cutting blade 21 on the hot press cylinder 20 is equal to the depth of its corresponding annular groove 32. The thickness of the cutting blade 21 on the hot press cylinder 20 is not higher than the width of its corresponding annular groove 32. The upper mold 2 has a heating function.

[0081] The specific stamping process is as follows: the inner feathers are cut into sheets using hot air nonwoven material to match the upper surface of the lower die 3, and laid flat on the upper surface of the lower die 3; the connecting rod 34 is clamped by the rocker arm 30, and the feather shaft is placed into the strip groove 31, so that the feather shaft head extends out of the outer side of the annular groove 32; the outer feathers are cut into the same size as the inner feathers using hot air nonwoven material, and laid flat on the inner feathers using hot air nonwoven material and above the feather shaft; the mold is started so that the upper die 2 moves downward, and the hot press cylinder 20 drives the cutting blade 21 to fit with the annular groove 32, and the shape of the feathers is formed by cutting with the blade. After cutting, the upper die 2 is reset, and the rocker arm 30 is rocked so that the connecting rod 34 rotates to release the feather shaft;

[0082] The specific hot pressing process is as follows: After the upper mold 2 is heated to 160°C, it moves downwards synchronously with the stamping action. The lower end face of the hot pressing cylinder 20 fits into the annular groove 32 of the lower mold 3. The temperature is maintained at 160°C for 5 seconds to melt the PE skin of the two layers of hot air nonwoven material, thereby achieving hot pressing bonding of the edge areas of the hot air nonwoven material for the inner feather and the hot air nonwoven material for the outer feather. After the hot pressing is completed, the upper mold 2 is reset, and the formed artificial feather can be taken out after the material cools down.

[0083] Example 1

[0084] A method for preparing an artificial badminton shuttlecock, the specific steps of which are as follows:

[0085] (1) Preparation of materials;

[0086] Inner feather raw material: PP / PE bicomponent core-sheath composite fiber (PE sheath melting point is 139.7℃, sheath thickness is 2μm, core PP melting point is 175.7℃), fiber diameter d1=12μm, fiber length is 40mm;

[0087] Outer bark material: PP / PE bicomponent core-sheath composite fiber (PE sheath melting point is 139.7℃, sheath thickness is 6μm, core PP melting point is 175.7℃), fiber diameter d2=36μm, fiber length is 40mm;

[0088] Unidirectional carbon fiber prepreg: 0.25 mm thick, 300 g / m² areal density. 2 The epoxy resin content is 35 wt%.

[0089] Low melting point 4080 fiber: The LMPET (low melting point polyethylene terephthalate) of the leather material has a melting point of 110℃;

[0090] Ball head: Composite cork ball head, weighing 2.4g;

[0091] (2) Preparation of carbon fiber reinforced resin matrix composite plates and non-woven fabrics;

[0092] The preparation process of carbon fiber reinforced resin matrix composite board is as follows: take two layers of unidirectional carbon fiber prepreg, stack them, place them in a hot press, and obtain carbon fiber reinforced resin matrix composite board after hot pressing and curing; wherein, the process parameters of hot pressing and curing are: temperature 180℃, pressure 0.5MPa, time 15min.

[0093] The preparation process of nonwoven fabric is as follows: low melting point 4080 fibers are sequentially carded into a web and needle-punched for pre-reinforcement to obtain nonwoven fabric; the process parameters for carding into a web are: feeding speed 0.68 r / min, cylinder speed 300 r / min, doffer speed 7.11 r / min, random speed 6.02 r / min, and roll-up speed 11.47 r / min; the process parameters for needle-punching for pre-reinforcement are: needle density 2250 needles / m, needle punching frequency 200 r / min, web output speed 1 m / min, needle punching depth 5 mm, and step size 6 mm / needle;

[0094] The carbon fiber reinforced resin matrix composite board has a thickness of 0.4 mm, a surface density of 600 g / m², a longitudinal tensile strength of 853 MPa, a transverse tensile strength of 439 MPa, and a flexural strength of 97 MPa; the non-woven fabric has a surface density of 100 g / m².

[0095] (3) Preparation of feather shafts;

[0096] The carbon fiber reinforced resin matrix composite board is sandwiched between two pieces of non-woven fabric, placed in a hot press for hot pressing and then cut to obtain the feather shaft. The hot pressing process parameters are as follows: the hot pressing temperature is 1.82 times the melting point of the low melting point 4080 fiber lining, the hot pressing time is 200s, and the hot pressing pressure is 0.5MPa.

[0097] The feather shaft has a mass of 0.0736g, a thickness of 0.62mm, and a surface density of 800g / m³. 2 In carbon fiber reinforced resin matrix composite plates, the carbon fibers are arranged parallel to the length direction of the fletching shaft; for example... Figure 5As shown, the fletching shaft 1 is spear-shaped and consists of a shaft 10 and a head 11. The shaft 10 increases in width from the end furthest from the head 11 to the end closest to the head 11, with a minimum width of 0.5 mm and a maximum width of 1.4 mm. The shaft 10 is 63 mm long, the head 11 is 11 mm long, and the head 11 has a maximum width of 3 mm.

[0098] (4) Preparation of hot air nonwoven materials for inner barbs and hot air nonwoven materials for outer barbs;

[0099] The preparation process of the hot-air nonwoven material for inner feathers is as follows: the inner feather raw material is sequentially carded into a web and then reinforced with hot air to obtain the hot-air nonwoven material for inner feathers; the process parameters for carding into a web are: cotton feeding speed 0.68 r / min, cylinder speed 300 r / min, doffer speed 7.11 r / min, random speed 6.02 r / min, and roll-up speed 11.47 r / min; the process parameters for hot air reinforcement are: hot air temperature 1.14 times the melting point of the inner feather raw material sheath, and hot air treatment time 100 s;

[0100] The preparation process of hot-air nonwoven material for outer feathers is as follows: the outer feather raw material is sequentially carded into a web and then reinforced with hot air to obtain the hot-air nonwoven material for outer feathers; the process parameters for carding into a web are: cotton feeding speed 0.68 r / min, cylinder speed 300 r / min, doffer speed 7.11 r / min, random speed 6.02 r / min, and roll-up speed 11.47 r / min; the process parameters for hot air reinforcement are: hot air temperature 1.14 times the melting point of the outer feather raw material skin, and hot air treatment time 100 s;

[0101] (5) Preparation of artificial feather pieces;

[0102] After clamping one end of the feather shaft between the inner feather vane hot-air nonwoven material fiber web and the outer feather vane hot-air nonwoven material, the two hot-air nonwoven material fiber webs are punched and hot-pressed to obtain artificial feathers.

[0103] like Figure 6 and Figure 8 As shown, the artificial feather consists of a vane 4 and a shaft 1. The vane 4 is composed of an inner vane 41 and an outer vane 42. The fiber 6 in both the inner and outer vanes 41 and 42 is arranged perpendicular to the length direction of the shaft 1. The inner vane 41 has an areal density of 75 g / m², a longitudinal strength of 107.2 N, a longitudinal elongation of 27.12%, a transverse strength of 20.1 N, a transverse elongation of 78.57%, a longitudinal bending stiffness of 24.3 mN·cm, a transverse bending stiffness of 10.3 mN·cm, and an air permeability of 2115.62 mm·s. -1The average pore size is 36 μm; the areal density of outer barbs 42 is 75 g / m², the longitudinal strength is 51.3 N, the longitudinal elongation is 35.34%, the transverse strength is 12.7 N, the transverse elongation is 86.8%, the longitudinal bending stiffness is 30.1 mN·cm, the transverse bending stiffness is 15.3 mN·cm, and the air permeability is 4123.34 mm·s. -1 The average aperture is 6.25 times the average aperture of inner vane 41; the mass of vane 4 is 0.072g;

[0104] (6) Assembly of artificial shuttlecocks;

[0105] Select 16 artificial feathers, insert the tip of each artificial feather evenly into the head of the shuttlecock, then position and adjust the inserted artificial feathers so that the 16 feathers are evenly distributed around the circumference of the head of the shuttlecock. Finally, use a binding thread to fix the connection between the feathers and the head of the shuttlecock to complete the assembly of the artificial badminton shuttlecock.

[0106] like Figure 7 As shown, the final artificial shuttlecock is mainly composed of a shaft 1, a feather vane 4, and a head 5; the center of gravity of the artificial shuttlecock is 5.16 mm from the surface of the head, and the mass of the artificial feather vane inserted into the head is 0.022 g; the rotation speed of the artificial shuttlecock is 435 r / min, the flight stability is 7.2 points, the durability is 9.2 points, and the feel of hitting the shuttlecock is 7 points.

[0107] Comparative Example 1

[0108] The method for preparing an artificial badminton shuttlecock differs from Example 1 in that the inner feather material is made of PP / PE bicomponent core-shell composite fiber (the melting point of the PE outer layer is 139.7℃, the thickness of the outer layer is 2μm, and the melting point of the PP core layer is 175.7℃), with a fiber diameter d1=36μm and a fiber length of 40mm.

[0109] The final artificial shuttlecock had a spin speed of 280 r / min, a flight stability score of 4.2, and a durability score of 5.5.

[0110] Compared with Comparative Example 1 and Example 1, the spin speed, flight stability and durability of the artificial badminton shuttlecock are significantly worse. This is because both the inner and outer feathers are made of relatively large diameter fibers with a diameter of 36μm. This results in a higher air permeability of the inner and outer feathers. However, the higher air permeability means that the airflow cannot provide enough resistance to ensure a high spin speed of the shuttlecock. At the same time, it will increase the pressure drag during flight, resulting in a slower flight speed. Furthermore, the use of coarse fibers in both the inner and outer feathers reduces the bonding points between the fibers, which in turn leads to a decrease in mechanical properties and ultimately affects the durability.

[0111] Comparative Example 2

[0112] The method for preparing an artificial badminton shuttlecock differs from Example 1 in that: in step (5), the laying orientation of the hot air nonwoven material fiber web for the inner feather and the hot air nonwoven material fiber web for the outer feather is adjusted, so that the fiber arrangement direction in the inner and outer feathers of the artificial feather is parallel to the length direction of the feather shaft.

[0113] The final artificial shuttlecock achieved a flight stability score of 4.5.

[0114] Compared to Example 1, the flight stability of the artificial shuttlecock was significantly worse. This is partly because the fiber arrangement in both the inner and outer vanes is parallel to the length of the shaft. The longitudinal (i.e., fiber arrangement direction) stiffness of the hot-air nonwoven material is higher than its transverse stiffness. During flight and impact, the direction in which the vanes are prone to bending and turning is perpendicular to the shaft. This arrangement results in insufficient resistance to bending and turning in this direction, leading to disordered feathering during impact and affecting flight stability. On the other hand, when the fiber arrangement in both the inner and outer vanes is parallel to the length of the shaft, the pores inside the vanes (mainly the pores between fibers) are also more oriented parallel to the length of the shaft. When airflow occurs, it does not flow out along the sides of the shaft like natural feathers, but rather along the shaft direction. This change in airflow direction affects flight stability.

[0115] Example 2

[0116] A method for preparing an artificial badminton shuttlecock, the specific steps of which are as follows:

[0117] (1) Preparation of materials;

[0118] Inner feather raw material: PP / PE bicomponent core-sheath composite fiber (PE sheath melting point is 139.7℃, sheath thickness is 10μm, core PP melting point is 175.7℃), fiber diameter d1=30μm, fiber length is 40mm;

[0119] Outer bark material: PP / PE bicomponent core-sheath composite fiber (PE sheath melting point is 139.7℃, sheath thickness is 2μm, core PP melting point is 175.7℃), fiber diameter d2=15μm, fiber length is 40mm;

[0120] Unidirectional carbon fiber prepreg: 0.5 mm thick, 300 g / m² areal density. 2 The epoxy resin content is 38 wt%.

[0121] Low melting point 4080 fiber: The melting point of the LMPET leather is 110℃;

[0122] Composite cork ball head: Weight 2.5g;

[0123] (2) Preparation of carbon fiber reinforced resin matrix composite plates and non-woven fabrics;

[0124] The preparation process of carbon fiber reinforced resin matrix composite board is as follows: take two layers of unidirectional carbon fiber prepreg, stack them, place them in a hot press, and obtain carbon fiber reinforced resin matrix composite board after hot pressing and curing; wherein, the process parameters of hot pressing and curing are: temperature 180℃, pressure 0.5MPa, time 15min.

[0125] The preparation process of nonwoven fabric is as follows: low melting point 4080 fibers are sequentially carded into a web and needle-punched for pre-reinforcement to obtain nonwoven fabric; the process parameters for carding into a web are: feeding speed 0.55 r / min, cylinder speed 280 r / min, doffer speed 6.9 r / min, random speed 6.5 r / min, and roll-up speed 12.03 r / min; the process parameters for needle-punching for pre-reinforcement are: needle density 2250 needles / m, needle punching frequency 180 r / min, web output speed 1.5 m / min, needle punching depth 2 mm, and step amount 2 mm / needle;

[0126] The carbon fiber reinforced resin matrix composite board has a thickness of 0.85 mm, a surface density of 650 g / m², a longitudinal tensile strength of 1245 MPa, a transverse tensile strength of 649 MPa, and a flexural strength of 192 MPa; the non-woven fabric has a surface density of 100 g / m².

[0127] (3) Preparation of feather shafts;

[0128] The carbon fiber reinforced resin matrix composite board is sandwiched between two pieces of non-woven fabric, placed in a hot press for hot pressing and then cut to obtain the feather shaft. The hot pressing process parameters are as follows: the hot pressing temperature is 1.82 times the melting point of the low melting point 4080 fiber lining, the hot pressing time is 200s, and the hot pressing pressure is 0.5MPa.

[0129] The feather shaft has a mass of 0.0782g, a thickness of 1.08mm, and a surface density of 850g / m³. 2 In the carbon fiber reinforced resin matrix composite board, the carbon fiber arrangement direction is parallel to the length direction of the fletching shaft; the fletching shaft is spear-shaped and consists of a shaft and a head; the width of the shaft increases from the end furthest from the head to the end closest to the head, with a minimum width of 0.6 mm and a maximum width of 1.5 mm; the length of the shaft is 63 mm; the length of the head is 14 mm; and the maximum width of the head is 3.5 mm.

[0130] (4) Preparation of hot air nonwoven materials for inner barbs and hot air nonwoven materials for outer barbs;

[0131] The preparation process of the hot-air nonwoven material for inner feathers is as follows: the inner feather raw material is sequentially carded into a web and then reinforced with hot air to obtain the hot-air nonwoven material for inner feathers; the process parameters for carding into a web are: feeding speed 0.52 r / min, cylinder speed 320 r / min, doffer speed 6.92 r / min, random speed 6.53 r / min, and winding speed 12.01 r / min; the process parameters for hot air reinforcement are: hot air temperature 1.25 times the melting point of the inner feather raw material sheath, and hot air treatment time 110 s;

[0132] The preparation process of hot-air nonwoven material for outer feathers is as follows: the outer feather raw material is sequentially carded into a web and then reinforced with hot air to obtain the hot-air nonwoven material for outer feathers; the process parameters for carding into a web are: cotton feeding speed 0.52 r / min, cylinder speed 320 r / min, doffer speed 6.92 r / min, randomization speed 6.53 r / min, and roll-up speed 12.01 r / min; the process parameters for hot air reinforcement are: hot air temperature 1.25 times the melting point of the outer feather raw material skin, and hot air treatment time 110 s;

[0133] (5) Preparation of artificial feather pieces;

[0134] After clamping one end of the feather shaft between the inner feather vane hot-air nonwoven material fiber web and the outer feather vane hot-air nonwoven material, the two hot-air nonwoven material fiber webs are punched and hot-pressed to obtain artificial feathers.

[0135] The artificial feather consists of inner vanes, outer vanes, and quills. The fibers in both the inner and outer vanes are arranged perpendicular to the length of the quill. The inner vanes have an areal density of 130 g / m², a longitudinal strength of 82.7 N, a longitudinal elongation of 33.41%, a transverse strength of 29.8 N, a transverse elongation of 82.17%, a longitudinal bending stiffness of 43.6 mN·cm, a transverse bending stiffness of 21.6 mN·cm, and an air permeability of 2447.21 mm·s. -1 The average pore size is 64 μm; the areal density of the outer barbs is 20 g / m², the longitudinal strength is 24.6 N, the longitudinal elongation is 36.47%, the transverse strength is 8.9 N, the transverse elongation is 81.78%, the longitudinal bending stiffness is 10.2 mN·cm, the transverse bending stiffness is 6.2 mN·cm, and the air permeability is 6102.21 mm·s. -1 The average aperture is 3.16 times the average aperture of the inner barbs; the total mass of the inner and outer barbs in the artificial feather is 0.072g.

[0136] (6) Assembly of artificial shuttlecocks;

[0137] Sixteen artificial feathers are selected, and the tip of each artificial feather is evenly inserted into the composite cork head. The inserted artificial feathers are then positioned and adjusted so that the 16 feathers are evenly distributed around the circumference of the head. Finally, the connection between the feathers and the head is fixed by binding with thread to complete the assembly of the artificial badminton shuttlecock.

[0138] The final artificial shuttlecock has a center of gravity 5.32 mm from the head surface, and the mass of the artificial feathers inserted into the composite cork head is 0.028 g. The artificial shuttlecock has a rotation speed of 420 r / min, a flight stability score of 7, a durability score of 8.8, and a hitting feel score of 6.

[0139] Comparative Example 3

[0140] The difference between the preparation method of an artificial badminton shuttlecock and Example 2 is that: in the preparation process of the inner feathers using hot air nonwoven material in step (4), the process parameters for combing into a web are: cotton feeding speed 0.52r / min, cylinder speed 320r / min, doffer speed 9r / min, random speed 8.50r / min, and rolling speed 15.6r / min; the adjustment of the process parameters makes the areal density of the inner feathers in the artificial feathers obtained in step (5) 100g / m², and the average pore size of the outer feathers is 2.5 times that of the average pore size of the inner feathers.

[0141] The final artificial shuttlecock achieved a flight stability score of 5.5.

[0142] Compared with Comparative Example 3 and Example 2, the flight stability of the artificial shuttlecock is significantly worse. This is because the ratio of the average aperture of the outer feather vanes to the average aperture of the inner feather vanes is less than 3. The apertures of the inner and outer feather vanes are too close, and the structure cannot better simulate the structure of natural feathers to achieve good control of airflow.

[0143] Example 3

[0144] A method for preparing an artificial badminton shuttlecock, the specific steps of which are as follows:

[0145] (1) Preparation of materials;

[0146] Inner feather raw material: PP / PE bicomponent core-sheath composite fiber (PE sheath melting point is 139.7℃, sheath thickness is 5μm, core PP melting point is 175.7℃), fiber diameter d1=15μm, fiber length is 40mm;

[0147] Outer bark material: PP / PE bicomponent core-sheath composite fiber (PE sheath melting point is 139.7℃, sheath thickness is 10μm, core PP melting point is 175.7℃), fiber diameter d2=30μm, fiber length is 40mm;

[0148] Unidirectional carbon fiber prepreg: 0.22 mm thick, 200 g / m² areal density. 2 The epoxy resin content is 38 wt%.

[0149] Low melting point 4080 fiber: The melting point of the LMPET leather is 110℃;

[0150] Composite cork ball head: Weight 2.45g;

[0151] (2) Preparation of carbon fiber reinforced resin matrix composite plates and non-woven fabrics;

[0152] The preparation process of carbon fiber reinforced resin matrix composite board is as follows: take two layers of unidirectional carbon fiber prepreg, stack them, place them in a hot press, and obtain carbon fiber reinforced resin matrix composite board after hot pressing and curing; wherein, the process parameters of hot pressing and curing are: temperature 160℃, pressure 1MPa, time 20min.

[0153] The preparation process of nonwoven fabric is as follows: low melting point 4080 fibers are sequentially carded into a web and needle-punched for pre-reinforcement to obtain nonwoven fabric; the process parameters for carding into a web are: feeding speed 0.55 r / min, cylinder speed 280 r / min, doffer speed 7.23 r / min, random speed 5.8 r / min, and roll-up speed 9.21 r / min; the process parameters for needle-punching for pre-reinforcement are: needle density 2250 needles / m, needle punching frequency 240 r / min, web output speed 0.8 m / min, needle punching depth 3 mm, and step size 4 mm / needle;

[0154] The carbon fiber reinforced resin matrix composite board has a thickness of 0.35 mm, a surface density of 550 g / m², a longitudinal tensile strength of 802 MPa, a transverse tensile strength of 403 MPa, and a flexural strength of 82 MPa; the non-woven fabric has a surface density of 50 g / m².

[0155] (3) Preparation of feather shafts;

[0156] The carbon fiber reinforced resin matrix composite board is sandwiched between two pieces of non-woven fabric, placed in a hot press for hot pressing and then cut to obtain the feather shaft. The hot pressing process parameters are as follows: the hot pressing temperature is 1.45 times the melting point of the low melting point 4080 fiber lining, the hot pressing time is 300s, and the hot pressing pressure is 1.8MPa.

[0157] The feather shaft has a mass of 0.0598g, a thickness of 0.55mm, and a surface density of 650g / m³. 2In the carbon fiber reinforced resin matrix composite plate, the carbon fiber arrangement direction is parallel to the length direction of the fletching shaft; the fletching shaft is spear-shaped and consists of a shaft and a head; the width of the shaft increases from the end furthest from the head to the end closest to the head, with a minimum width of 0.4 mm and a maximum width of 1.3 mm; the length of the shaft is 63 mm; the length of the head is 9 mm; and the maximum width of the head is 2.5 mm.

[0158] (4) Preparation of hot air nonwoven materials for inner barbs and hot air nonwoven materials for outer barbs;

[0159] The preparation process of the hot-air nonwoven material for inner feathers is as follows: the inner feather raw material is sequentially carded into a web and then reinforced with hot air to obtain the hot-air nonwoven material for inner feathers; the process parameters for carding into a web are: feeding speed 0.72 r / min, cylinder speed 280 r / min, doffer speed 7.41 r / min, random speed 5.82 r / min, and roll-up speed 9.11 r / min; the process parameters for hot air reinforcement are: hot air temperature 1.15 times the melting point of the inner feather raw material sheath, and hot air treatment time 120 s;

[0160] The preparation process of hot-air nonwoven material for outer feathers is as follows: the outer feather raw material is sequentially carded into a web and then reinforced with hot air to obtain the hot-air nonwoven material for outer feathers; the process parameters for carding into a web are: feeding speed 0.72 r / min, cylinder speed 280 r / min, doffer speed 7.41 r / min, randomization speed 5.82 r / min, and roll-up speed 9.11 r / min; the process parameters for hot air reinforcement are: hot air temperature 1.15 times the melting point of the outer feather raw material skin, and hot air treatment time 120 s;

[0161] (5) Preparation of artificial feather pieces;

[0162] After clamping one end of the feather shaft between the inner feather vane hot-air nonwoven material fiber web and the outer feather vane hot-air nonwoven material, the two hot-air nonwoven material fiber webs are punched and hot-pressed to obtain artificial feathers.

[0163] The artificial feather consists of inner vanes, outer vanes, and quills. The fibers in both the inner and outer vanes are arranged perpendicular to the length of the quill. The inner vanes have an areal density of 45 g / m², a longitudinal strength of 62.5 N, a longitudinal elongation of 28.32%, a transverse strength of 9.7 N, a transverse elongation of 80.45%, a longitudinal bending stiffness of 16.5 mN·cm, a transverse bending stiffness of 6.1 mN·cm, and an air permeability of 2378.45 mm·s. -1The average pore size is 47 μm; the areal density of the outer barbs is 45 g / m², the longitudinal strength is 35.8 N, the longitudinal elongation is 32.16%, the transverse strength is 7.9 N, the transverse elongation is 92.21%, the longitudinal bending stiffness is 16.8 mN·cm, the transverse bending stiffness is 9.2 mN·cm, and the air permeability is 4093.67 mm·s. -1 The average aperture is 4.45 times the average aperture of the inner barbs; the total mass of the inner and outer barbs in the artificial feather is 0.0435g.

[0164] (6) Assembly of artificial shuttlecocks;

[0165] Sixteen artificial feathers are selected, and the tip of each artificial feather is evenly inserted into the composite cork head. The inserted artificial feathers are then positioned and adjusted so that the 16 feathers are evenly distributed around the circumference of the head. Finally, the connection between the feathers and the head is fixed by binding with thread to complete the assembly of the artificial badminton shuttlecock.

[0166] The final artificial shuttlecock has a center of gravity 5.24 mm from the head surface, and the mass of the artificial feathers inserted into the composite cork head is 0.015 g. The artificial shuttlecock has a rotation speed of 390 r / min, a flight stability score of 6, a durability score of 6.5, and a hitting feel score of 6.5.

[0167] Example 4

[0168] A method for preparing an artificial badminton shuttlecock, the specific steps of which are as follows:

[0169] (1) Preparation of materials;

[0170] Inner feather raw material: PP / PE bicomponent core-sheath composite fiber (PE sheath melting point is 139.7℃, sheath thickness is 5μm, core PP melting point is 175.7℃), fiber diameter d1=15μm, fiber length is 40mm;

[0171] Outer bark material: PP / PE bicomponent core-sheath composite fiber (PE sheath melting point is 139.7℃, sheath thickness is 10μm, core PP melting point is 175.7℃), fiber diameter d2=30μm, fiber length is 40mm;

[0172] Unidirectional carbon fiber prepreg: 0.25 mm thick, 250 g / m² areal density. 2 The epoxy resin content is 38 wt%.

[0173] Low melting point 4080 fiber: The melting point of the LMPET leather is 110℃;

[0174] Composite cork ball head: Weight 2.45g;

[0175] (2) Preparation of carbon fiber reinforced resin matrix composite plates and non-woven fabrics;

[0176] The preparation process of carbon fiber reinforced resin matrix composite board is as follows: take two layers of unidirectional carbon fiber prepreg, stack them, place them in a hot press, and obtain carbon fiber reinforced resin matrix composite board after hot pressing and curing; wherein, the process parameters of hot pressing and curing are: temperature 160℃, pressure 1MPa, time 20min.

[0177] The preparation process of nonwoven fabric is as follows: low melting point 4080 fibers are sequentially carded into a web and needle-punched for pre-reinforcement to obtain nonwoven fabric; the process parameters for carding into a web are: feeding speed 0.72 r / min, cylinder speed 320 r / min, doffer speed 7.23 r / min, random speed 5.8 r / min, and roll-up speed 9.21 r / min; the process parameters for needle-punching for pre-reinforcement are: needle density 2250 needles / m, needle punching frequency 220 r / min, web output speed 0.9 m / min, needle punching depth 3 mm, and step size 4 mm / needle;

[0178] The carbon fiber reinforced resin matrix composite board has a thickness of 0.38 mm, a surface density of 580 g / m², a longitudinal tensile strength of 819 MPa, a transverse tensile strength of 415 MPa, and a flexural strength of 91 MPa; the non-woven fabric has a surface density of 75 g / m².

[0179] (3) Preparation of feather shafts;

[0180] The carbon fiber reinforced resin matrix composite board is sandwiched between two pieces of non-woven fabric, placed in a hot press for hot pressing and then cut to obtain the feather shaft. The hot pressing process parameters are as follows: the hot pressing temperature is 1.64 times the melting point of the low melting point 4080 fiber lining, the hot pressing time is 250s, and the hot pressing pressure is 1.3MPa.

[0181] The feather shaft has a mass of 0.0672g, a thickness of 0.58mm, and a surface density of 730g / m³. 2 In the carbon fiber reinforced resin matrix composite board, the carbon fiber arrangement direction is parallel to the length direction of the fletching shaft; the fletching shaft is spear-shaped and consists of a shaft and a head; the width of the shaft increases from the end furthest from the head to the end closest to the head, with a minimum width of 0.5 mm and a maximum width of 1.5 mm; the length of the shaft is 63 mm; the length of the head is 9 mm; and the maximum width of the head is 2 mm.

[0182] (4) Preparation of hot air nonwoven materials for inner barbs and hot air nonwoven materials for outer barbs;

[0183] The preparation process of the hot-air nonwoven material for inner feathers is as follows: the inner feather raw material is sequentially carded into a web and then reinforced with hot air to obtain the hot-air nonwoven material for inner feathers; the process parameters for carding into a web are: cotton feeding speed 0.62 r / min, cylinder speed 300 r / min, doffer speed 7.04 r / min, random speed 6.21 r / min, and roll-up speed 8.87 r / min; the process parameters for hot air reinforcement are: hot air temperature 1.21 times the melting point of the inner feather raw material sheath, and hot air treatment time 90 s;

[0184] The preparation process of hot-air nonwoven material for outer feathers is as follows: the outer feather raw material is sequentially carded into a web and then reinforced with hot air to obtain the hot-air nonwoven material for outer feathers; the process parameters for carding into a web are: cotton feeding speed 0.62 r / min, cylinder speed 300 r / min, doffer speed 7.04 r / min, random speed 6.21 r / min, and roll-up speed 8.87 r / min; the process parameters for hot air reinforcement are: hot air temperature 1.21 times the melting point of the outer feather raw material skin, and hot air treatment time 90 s;

[0185] (5) Preparation of artificial feather pieces;

[0186] After clamping one end of the feather shaft between the inner feather vane hot-air nonwoven material fiber web and the outer feather vane hot-air nonwoven material, the two hot-air nonwoven material fiber webs are punched and hot-pressed to obtain artificial feathers.

[0187] The artificial feather consists of inner vanes, outer vanes, and quills. The fibers in both the inner and outer vanes are arranged perpendicular to the length of the quill. The inner vanes have an areal density of 90 g / m², a longitudinal strength of 123.8 N, a longitudinal elongation of 26.21%, a transverse strength of 31.5 N, a transverse elongation of 68.9%, a longitudinal bending stiffness of 32.8 mN·cm, a transverse bending stiffness of 16.3 mN·cm, and an air permeability of 1997.89 mm·s. -1 The average pore size is 31 μm; the areal density of the outer barbs is 30 g / m², the longitudinal strength is 28.7 N, the longitudinal elongation is 38.21%, the transverse strength is 6.5 N, the transverse elongation is 95.6%, the longitudinal bending stiffness is 15.8 mN·cm, the transverse bending stiffness is 7.2 mN·cm, and the air permeability is 4873.45 mm·s. -1 The average aperture is 10.33 times the average aperture of the inner barbs; the total mass of the inner and outer barbs in the artificial feather is 0.058g.

[0188] (6) Assembly of artificial shuttlecocks;

[0189] Sixteen artificial feathers are selected, and the tip of each artificial feather is evenly inserted into the composite cork head. The inserted artificial feathers are then positioned and adjusted so that the 16 feathers are evenly distributed around the circumference of the head. Finally, the connection between the feathers and the head is fixed by binding with thread to complete the assembly of the artificial badminton shuttlecock.

[0190] The final artificial shuttlecock has a center of gravity 5.41 mm from the head surface, and the mass of the artificial feathers inserted into the composite cork head is 0.019 g. The artificial shuttlecock has a rotation speed of 410 r / min, a flight stability score of 7, a durability score of 8.1, and a hitting feel score of 6.

[0191] Comparative Example 4

[0192] The difference between the preparation method of an artificial badminton shuttlecock and Example 4 is that: in the preparation process of hot air nonwoven material for the outer feathers in step (4), the process parameters for combing into a web are: cotton feeding speed 0.52r / min, cylinder speed 320r / min, doffer speed 10.38r / min, random speed 9.80r / min, and rolling speed 16.02r / min; the adjustment of the process parameters makes the surface density of the outer feathers in the artificial feathers obtained in step (5) 20g / m², and the average pore size of the outer feathers is 12 times that of the average pore size of the inner feathers.

[0193] The final artificial shuttlecock was rated as having a durability score of 6.

[0194] Compared with Comparative Example 4 and Example 4, the durability of the artificial badminton shuttlecock is significantly worse. This is because the ratio of the average aperture of the outer feather vanes to the average aperture of the inner feather vanes is greater than 11, the difference in aperture between the inner and outer feather vanes is too large, and the outer feather vanes have a loose structure due to fewer fiber bonding points, resulting in poor mechanical properties, insufficient durability, and easy breakage from impact.

Claims

1. An artificial feather, comprising an inner feather, an outer feather, and a quill held between the two at one end, wherein both the inner and outer feathers are cut from a hot-air nonwoven fiber web, the hot-air nonwoven fiber web being formed by carding low-melting-point fibers and reinforcing them with hot air, characterized in that... The fibers in the inner pinnae have the same diameter, denoted as d1, and the fibers in the outer pinnae have the same diameter, denoted as d2. The values ​​of d1 and d2 are both in the range of 12~36μm, and d1≠d2. The sum of the areal density of the inner and outer barbs is 90~150 g / m². 2 The total mass of the inner and outer barbs is 0.0435~0.0720g, and the average aperture of the outer barbs is 3~11 times that of the average aperture of the inner barbs; The edges of the inner and outer barbs are joined by thermo-press bonding, and the fiber arrangement in both the inner and outer barbs is perpendicular to the length of the quill.

2. The artificial feather according to claim 1, characterized in that, The low-melting-point fiber is a PP / PE bicomponent core-sheath composite fiber, with PE as the sheath material and a sheath thickness of 2~10μm; The process parameters for carding and web formation include: feeding speed 0.52~0.74 r / min, cylinder speed 280~320 r / min, doffer speed 6.83~7.45 r / min, randomization speed 5.64~6.56 r / min, and lap formation speed 8.65~12.14 r / min; The process parameters for hot air reinforcement include: hot air temperature is 1.14 to 1.25 times the melting point of the low-melting-point fiber leather, and hot air treatment time is 90 to 120 seconds.

3. The artificial feather piece according to claim 1, characterized in that, The shaft is spear-shaped, consisting of a shaft and a head. The head is used to insert into the ball. The shaft is 0.55 to 1.08 mm thick. The shaft is wider at the end furthest from the head and closer to the head, with a minimum width of 0.4 to 0.6 mm and a maximum width of 1.3 to 1.5 mm. The shaft is 63 to 64 mm long, the head is 9 to 14 mm long, and the head has a maximum width of 2 to 3.5 mm.

4. The artificial feather piece according to claim 1, characterized in that, The feather shaft consists of two non-woven fabric layers and a carbon fiber reinforced resin matrix composite plate sandwiched between them; The areal density of nonwoven fabric is 50~100 g / m². 2 ; In the carbon fiber reinforced resin matrix composite plate, the carbon fibers are arranged parallel to the length direction of the fletching shaft; the thickness of the carbon fiber reinforced resin matrix composite plate is 0.35~0.85mm, and the areal density is 550~650g / m³. 2 ; Nonwoven fabric is obtained by carding low-melting-point 4080 fibers into a web and then pre-reinforcing them with needle punching. The carding process parameters include: feeding speed 0.52~0.74 r / min, cylinder speed 280~320 r / min, doffer speed 6.83~7.45 r / min, randomization speed 5.64~6.56 r / min, and roll-up speed 8.65~12.14 r / min. The needle punching pre-reinforcing process parameters include: needle density 2250 needles / m, needle punching frequency 160~240 r / min, web output speed 0.8~1.5 m / min, needle punching depth 1~5 mm, and step size 2~6 mm / needle. Carbon fiber reinforced resin matrix composite panels are obtained by laminating two layers of unidirectional carbon fiber prepreg and then hot-pressing and curing them; wherein the thickness of the unidirectional carbon fiber prepreg is 0.2~0.5mm and the areal density is 200~300g / m³. 2 ; The preparation process of the feather shaft is as follows: a carbon fiber reinforced resin matrix composite plate is sandwiched between two pieces of non-woven fabric and hot-pressed together, and then cut to obtain the feather shaft; the process parameters of hot-pressing include: hot-pressing temperature is 1.45~1.82 times the melting point of the low melting point 4080 fiber lining, hot-pressing time is 200~300s, and hot-pressing pressure is 0.5~2MPa.

5. A method for preparing an artificial feather as described in any one of claims 1 to 4, characterized in that, After clamping one end of the feather shaft between two hot-air nonwoven fiber webs, the two hot-air nonwoven fiber webs are punched and hot-pressed to obtain the artificial feather.

6. The method according to claim 5, characterized in that, Stamping and hot pressing use a set of dies, which includes an upper die and a lower die; The upper surface of the lower die is a horizontal plane, on which at least one pair of strip grooves and annular grooves are provided. The annular groove surrounds one end of the same pair of strip grooves. The strip grooves are used to load feather shafts. The shape and size of the inner edge of the annular groove are the same as those of the inner and outer feathers. The lower surface of the upper mold is provided with a hot press cylinder corresponding to each annular groove. The lower end face of the hot press cylinder is a horizontal plane. The orthographic projection of the outer edge of the hot press cylinder completely coincides with the orthographic projection of the inner edge of the corresponding annular groove. The outer edge of the hot press cylinder extends downward to form a cutting blade. The cutting blade is provided with a notch to prevent cutting the feather rod. The height of the cutting blade on the hot press cylinder is equal to the depth of its corresponding annular groove. The thickness of the cutting blade on the hot press cylinder is not higher than the width of its corresponding annular groove. The upper mold has a heating function.

7. The method according to claim 6, characterized in that, The upper surface of the lower mold is rectangular, with a pair of opposite sides denoted as side a and side b, and the direction parallel to side a and side b is denoted as direction X; There are 2n pairs of strip grooves and annular grooves, where n is a positive integer; n pairs of strip grooves and annular grooves are arranged at intervals along the X direction, with the end of the strip groove not surrounded by the annular groove flush with side a; and n pairs of strip grooves and annular grooves are arranged at intervals along the X direction, with the end of the strip groove not surrounded by the annular groove flush with side b. The lower mold has two rocker arms parallel to the X direction on both sides. Each rocker arm has n connecting rods fixed vertically. The rocker arm and the n connecting rods form a comb-shaped structure. The free end of each connecting rod has a clamping port for clamping the feather shaft. One rocker arm is located near side a, and its n connecting rods are used to place n feather shafts into n strip-shaped grooves. Another rocker arm is located near side b, and its n connecting rods are used to place n feather shafts into another n strip-shaped grooves.

8. An artificial badminton shuttlecock, characterized in that, It includes a ball head and 16 artificial feathers as described in any one of claims 1 to 4, wherein the end of the artificial feather shaft away from the inner and outer vanes is inserted into the ball head.

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