Table tennis racket base made in seven layers

Abstract

FIELD: sports equipment.SUBSTANCE: invention is related in particular to the base of a table tennis racket, which promotes physical development and coordination of human movements. The base of a table tennis racket comprises a strip of radial wood cut vertically arranged to the layers of the base, and between the strip of radial wood cut and the base there is a strip of titanium alloy with a tensile strength σv<700 MPa÷σin>1000 MPa, thickness 0.3÷1 mm in height across the thickness of the racket base, and the central layer of wood of the racket base was exposed to a temperature of 150÷ 230°C.EFFECT: improvement of the device is ensured, the rigidity of the edges of the base is increased, the playing area, speed, rotation of the ball on the playing surface of the base are increased, and the weight of the base is reduced.1 cl, 2 dwg

Description

[0001] The invention relates to sports equipment, in particular to the base of a table tennis racket, which promotes physical development and coordination of human movements.

[0002] Racket bases are known that contain, under the first, which are the outer layers of wood, layers of composite: carbon (Carbon), V-carbon (VC), carbon CF (Carbon CF), light carbon (Soft Carbon), arylate (Arylate), arylate carbon (ALC), acrylic carbon (AC Carbon), hybrid carbon (Carbon CFL), aramid carbon (ARC), hybrid carbon (Carbon CFL), fiber, fiber carbon, fiberglass (Fiberglass), zeylon (Zylon), zeylon-carbon (ZLC), zeylon-fiber (ZLF), kevlar (Kevlar), Texalium, ULC, cellulose nanofiber CNF (Cellulose Nano Fiber), Super ZL Carbon (Super ZLC), TAMCA 5000, CAF (Control Assist Fiber), carbon glass (Carbon / glass), Pa-Carbon, X-Carbon, Zephylium, TeXtreme® Carbon (TMX).

[12] . The well-known Chinese company SWORD produces a large number of blades with synthetic fibers (composites) and their various mixtures. Among them are E-JLC fiber (full name Energy JULONG CARBON), JL Fiber (JU LONG), JL 1.5 Carbon fiber (1.5K JU LONG), MAX Carbon fiber, Al Carbon Yellow fiber, AL Carbon yellow 1.5 fiber, AL Carbon 2V1 fiber. [3]. Blades containing composite layers of one or more materials are called composite and are most suitable for effective play with a 40+ ball made of the new material.

[0003] Carbon CF provides better control and reliability than Aramid (ARC) or V-Carbon (VC). Ultra-fine CNF (Cellulose Nano Fiber) provides the blade with low vibration and a feeling of ball retention while maintaining high speed. TAMCA 5000 carbon fiber increases the stability and precision of the blade. Control Assist Fiber (CAF) increases stability, precision, and control of the blade, ensuring a consistent ball bounce across the entire playing surface. With the new Uniaxial Light-Constant (ULC) technology, all fibers are laid in the same direction, allowing Butterfly engineers to create a lighter Innerforce ULC carbon blade without sacrificing speed and with significantly improved ball feel.Butterfly's technology has evolved to create blades with ZLC composite, which offer higher speed and slightly less vibration. Instead of ALC, these blades utilize the even more advanced Super ZLC composite, which provides greater resilience due to the interweaving of more fibers than ALC. By adjusting the ratio of arylight and carbon materials, the blade maintains its elasticity. New processing technologies create a stronger bond between the carbon and zeylon fibers, resulting in blades with very little energy loss at the edges and a larger, more uniform sweet spot. Blades with ZLC and Super ZLC composites are characterized by high speed and spin, precision, and a natural touch, providing a fantastic feel. Despite this, arylight carbon (ALC) blades are still among the most popular composite blades because:

[0004] 1. This is the composite that tennis players love so much – blades with Arylate carbon cost much less than blades with ZLC and Super ZLC composites.

[0005] 2. Blades with ALC have a longer contact time between the ball and the racket. This is especially appreciated by players who are just building their first carbon racket. This property gives blades with ALC greater control compared to blades of the same or stiffer quality.

[0006] 3. ALC blades produce less vibration than ZLC or Super ZLC blades. There are two types of tennis players: some like blade vibration, others don't. However, the majority of players find it uncomfortable to play.

[0007] 4. Blades with ALC, thanks to their control and precision, are popular not only among amateurs. Many professional players also use blades with this type of composite. These blades are ideal for counterattacking and mid-range play.

[0008] An example of such blades are blades with the first plies of koto wood, the second plies of ALC composite, the third plies of limba wood, the center ply of kiri wood: Butterfly Viscaria ALC, Butterfly Timo Boll ALC, Butterfly Zhang Jike ALC, Butterfly Timo Boll Spirit ALC, Butterfly Liu Shiwen ALC, Butterfly Timo Boll W 5 ALC, Huieson 7 norm Arylate carbon fiber.

[0009] However, when playing with power equipment with high speed and ball spin, increased vibration of the blades and their edges occurs, which reduces the sweet spot and is a disadvantage.

[0010] There are known blades containing titanium layers (Andro KINETIC CF Titanium ALL+; Stiga Titan 5 / 4; metal nets (SWORD GOLDEN EAGLE GE), with aluminum alloy-filled microchannels (Stiga Tube Aluminum), DR NEUBAUER TITAN blade, PALIO 8603, Dr. Neubauer Colossus [4], in which the titanium layers are located parallel between the wood layers, which can increase the speed of the ball and the weight of the blade, but cannot reduce the increased vibration of the blades and their edges associated with the size of the playing spot, which is a disadvantage.

[0011] The most common grades of titanium are VT1-0, VT1-00, VT1-00sv, which are called technical (Ti), and do not contain alloying elements, but only a small amount of impurities. The Ti content in the VT1-0 grade is approximately 99.24-99.7%, in VT1-00 - 99.58-99.9%, VT1-00sv - 99.39-99.9%. VT1-0, VT1-00, are supplied in the form of sheets, plates, rods and pipes.

[0012] Advantages of technical titanium:

[0013] 1. Low density (4500 kg / m3 3 ) helps to reduce the weight of products.

[0014] 2. High mechanical strength. At elevated temperatures (250-500°C), titanium alloys are superior in strength to aluminum and magnesium alloys.

[0015] 3. High corrosion resistance due to the ability of Ti to form thin (5-15 µm) TiO2 oxide films on the surface, associated with the mass of the metal.

[0016] 4. The specific strength (the ratio of strength to density) of titanium alloys reaches 30-35 or more, which is twice the specific strength of alloy steels.

[0017] Disadvantages of technical titanium:

[0018] 1. High production cost of Ti is significantly more expensive than iron, aluminum, copper, magnesium.

[0019] 2. Active interaction at high temperatures, especially in the liquid state, with all gases that make up the atmosphere, as a result of which Ti and its alloys can only be melted in a vacuum or in an inert gas environment.

[0020] 3. Difficulties in involving titanium waste in production.

[0021] 4. Poor antifriction properties due to the adhesion of Ti to many materials; titanium paired with titanium cannot work under friction at all.

[0022] 5. High susceptibility of Ti and many of its alloys to hydrogen embrittlement and salt corrosion;

[0023] 6. Poor machinability, similar to that of austenitic stainless steels.

[0024] 7. High chemical activity, tendency to grain growth at high temperature and phase transformations during the welding cycle cause difficulties in welding titanium.

[0025] From the analysis of the existing “CLASSIFICATION OF INDUSTRIAL TITANIUM ALLOYS” [5, 6], it can be concluded that the most suitable method for reducing vibration of the bases and edges of racket bases may be the use of strips of titanium alloys of low strength and increased ductility. This group includes alloys with a tensile strength of σ в <700 MPa, namely: α-alloys of the VT1-00 and VT1-0 grades (technical titanium) and OT4-0 and OT4-1 alloys (Ti-Al-Mn system), AT3 (Ti-Al system with small additions of Cr, Fe, Si, and B), classified as pseudo-alloys with a small amount of the β-phase. The strength characteristics of these alloys are higher than those of pure titanium due to impurities in the VT1-00 and VT1-0 alloys and minor alloying with α- and β-stabilizers in the OT4-0, OT4-1, and AT3 alloys.

[0026] These alloys are characterized by high plasticity in both hot and cold states, which allows for the production of all types of semi-finished products: foil, tape, sheets, plates, forgings, stampings, profiles, pipes, etc. Strips of high-strength titanium alloys can also be used, which include alloys with a tensile strength of σ в >1000 MPa, namely (a+P)-alloys of the VT6, VT14, VT3-1, and VT22 grades. High strength in these alloys is achieved by hardening heat treatment (quenching and aging). The exception is the high-alloy VT22 alloy, which, even in the annealed condition, has σ в >1000 MPa. These alloys, along with high strength, retain good (VT6) and satisfactory (VT14, VT3-1, VT22) technological plasticity in a hot state, which allows them to be used to produce various semi-finished products: sheets (except VT3-1), rods, plates, forgings, stampings, profiles, etc. VT6 and VT14 alloys in annealed condition (σ в>850 MPa) can be cold stamped with small deformations. These alloys exhibit high corrosion resistance in the annealed and heat-hardened states. в humid atmospheres, seawater, and many other aggressive environments, just like technical titanium. Strips of medium-strength titanium alloys can also be used—this group includes alloys with a tensile strength of σ в=750÷1000 MPa, namely: α-alloys of the VT5 and VT5-1 grades; pseudo-α-alloys of the OT4, VT20 grades; (α+β) alloys of the PT3V grades, as well as VT6, VT6S, VT14 in the annealed condition. Alloys VT5, VT5-1, OT4, VT20, PT3V, VT6S, containing a small amount of the β-phase (2-7% of the β-phase in the equilibrium state), are not subjected to strengthening heat treatment and are used in the annealed condition. Alloy VT6S is sometimes used in a heat-hardened condition. Alloys VT6 and VT14 are used both in annealed and heat-hardened condition. In the latter case, their strength becomes higher than 1000 MPa. In this case, the strengthening heat treatment and annealing must be carried out in a template in which the processed strip of titanium alloy takes the shape of the end of the base of the racket.

[0027] Also known are the blades of the Andro and Butterfly companies (Andro Temper TECH OFF-, Andro Temper TECH OFF, Butterfly Maze T-Tec Off, BUTTERFLY MAZE Magic), made by exposing the layers of wood to a temperature of 150÷230° to increase the playing area and durability, reducing the weight of the blade by 10-20%.

[0028] A racket base is known, comprising a playing part, a handle, a central layer of wood, third layers of wood and first layers of wood connected to them by an adhesive composition, which are outer, under which a second layer of composite is located: carbon (Carbon), V-carbon (VC), carbon CF (Carbon CF), light carbon (Soft Carbon), arylate (Arylate), arylate carbon (ALC), acrylic carbon (AC Carbon), hybrid carbon (Carbon CFL), aramid carbon (ARC), hybrid carbon (Carbon CFL), fiber, fiber carbon, fiberglass (Fiberglass), zeylon (Zylon), zeylon-carbon (ZLC), zeylon-fiber (ZLF), kevlar (Kevlar), Texalium, ULC, cellulose nanofiber CNF (Cellulose Nano Fiber), Super ZL Carbon (Super ZLC), TAMCA 5000, CAF (Control Assist Fiber), carbon glass (Carbon / glass), Pa-Carbon, X-Carbon, Zephylium, TeXtreme® Carbon (TMX), E-JLC fibers (full name Energy JULONG CARBON), JL Fiber (JU LONG), JL 1.5 Carbon fiber (1.5K JU LONG), JL 1.5 Carbon fiber, MAX Carbon fiber, Carbon fiber, Al Carbon Yellow fiber, AL Carbon yellow 1.5 fiber, AL Carbon 2V1 fiber, wherein the first layers are made of koto wood, the second layers are made of composite, the third layers are made of limba wood, the central layer is made of kiri wood: koto - composite - limba - kiri - limba - composite - koto, characterized in that the central layer of wood was exposed to a temperature of 150÷230°C, and one of the said second layers of the composite is also a JL Carbon fiber composite (JU LONG. [7].

[0029] The technical result of the invention is to improve the base, increase its technical characteristics, namely, increase the playing area, speed and rotation of the ball, durability of the base, and reduce the weight of the base.

[0030] The technical result is achieved due to new elements and their new connections in the base of the racket, namely: the base of the racket, containing the playing part 1, the handle 2, the central layer of wood 3, the second layers of composite 5 and the first layers of wood connected to them by an adhesive composition, which are the outer 4, wherein under the first layers of wood 4 there is one of the named layers of composite 6: carbon (Carbon), V-carbon (VC), carbon CF (Carbon CF), light carbon (Soft Carbon), arylate (Arylate), arylate carbon (ALC), acrylic carbon (AC Carbon), hybrid carbon (Carbon CFL), aramid carbon (ARC), hybrid carbon (Carbon CFL), fiber, fibercarbon, fiberglass (Fiberglass), zeylon (Zylon), zeylon-carbon (ZLC), Zylon fiber (ZLF), Kevlar, Texalium, ULC, Cellulose Nano Fiber (CNF), Super ZL Carbon (Super ZLC), TAMCA 5000, CAF (Control Assist Fiber), Carbon / glass, Pa-Carbon, X-Carbon, Zephylium, TeXtreme® Carbon (TMX),E-JLC fiber (full name Energy JULONG CARBON), JL Fiber (JU LONG), JL 1.5 Carbon fiber (1.5K JU LONG), JL 1.5 Carbon fiber, MAX Carbon fiber, Carbon fiber, Al Carbon Yellow fiber, AL Carbon yellow 1.5 fiber, AL Carbon 2V1 fiber, wherein the base contains a strip 7 made of a radial cut of wood with a thickness of 0.8÷3.0 mm, located vertically to the layers of the base, the width along the thickness of the base, the density exceeding the density of the upper layer of the base, which is glued to the end of the base to all layers of the base on both sides from the end of the playing part of the base opposite the handle, and the end of the strip of radial cut of wood 7 is located within the range from the middle of the playing spot to its end, wherein the first layers 4 are made of koto wood, the second layers 5 are made of composite, the third layers 6 are made of limba wood, the central layer 3 is made of wood kiri (kiri:), which was exposed to temperatures of 150÷230°C,and between the strip of radial wood cut 7 and the base 1, a strip of titanium alloy 8 with a tensile strength of σ is located vertically to the layers of the base, в <700 MPa÷σ в >1000 MPa, 0.3÷2 mm thick, height along the thickness of the base to increase the playing area, speed and rotation of the ball, reduce the weight of the base, and one of the second layers of the base is also an ALC composite.

[0031] Sources of information

[0032] 1. Composite materials: Carbon, Arylate - TTSPORT.RU table tennis.

[0033] 2. Butterfly ALC, ZLC, Super ZLC and other carbon technologies from Butterfly, https: / / pingpong73.ru / ttblog / butterfv-alc-zlc-super-zlc

[0034] 3. SWORD artificial fiber production technology, (Internet).

[0035] 4. Titanium bases, (Internet).

[0036] 5. Classification of industrial titanium alloys (Internet).

[0037] 6. Heat treatment of titanium, (Internet).

[0038] 7. Patent RU 2851655 C1: IPC A63B 59 / 00. Table tennis racket base made with seven layers. Tebenko Yu.M. No. 2024137174; declared 09.12.2024, published 26.11.2025, Bulletin 33. - 7 p.

[0039] List of figures on the drawing

[0040] Fig. 1 shows a side view of the base of the racket with the playing part 1 and the handle 2.

[0041] Fig. 2 shows a section A of the base with a central layer of wood 3, with the first, outer, layers of wood 4, with the second layers of wood 5, with layers of composite 6, with a strip of radial cut wood 7, with a strip of titanium alloy 8.

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