Park golf clubs containing coffee grounds

Abstract

The present invention relates to a park golf club (1) comprising a head (100) formed from a composite material including coffee grounds powder and synthetic resin, and a shaft (120) coupled to the head (100).

Description

Technology Field

[0001] The present disclosure relates to a park golf club comprising coffee grounds. Background Technology

[0002] Park golf clubs are generally manufactured from various materials, including wood, aluminum, and carbon fiber. When wood is used, the supply is limited, and its low durability and resistance to moisture and temperature changes can lead to deformation or cracking during long-term use. Furthermore, wood processing is not suitable for mass production, and environmental issues regarding the import of tropical timber are raised. While the application of synthetic materials such as aluminum or carbon fiber improves durability, the higher manufacturing costs make them inaccessible to the average user. Most existing park golf clubs are manufactured with standardized structures, lacking user customization and limiting weight distribution and balance adjustment. Additionally, the fixed connection between the head and shaft makes replacement or modularization difficult, and there are limitations in improving user feel, such as the head's shock absorption, rebound force, and sound control. Recently, there has been an increasing demand for the application of eco-friendly materials and recycled structures, but actual implementation is rare. Against this backdrop, there is a growing need for park golf clubs that incorporate new materials, streamline manufacturing processes, enhance user customization, and strengthen durability and environmental features. The problem to be solved

[0003] The objective of one embodiment is to provide a park golf club capable of resolving the limitations of existing park golf clubs, such as lack of material diversity, reduced durability, environmental issues, difficulties in mass production, lack of user customization, limitations in weight distribution and balance control, and limitations in improving shock absorption and rebound force, by applying a head molded from a composite material comprising coffee grounds powder and synthetic resin. means of solving the problem

[0004] A park golf club according to one embodiment may include a head molded from a composite material comprising coffee grounds powder and synthetic resin, and a shaft coupled to the head.

[0005] In a park golf club according to one embodiment, the head can be manufactured through a process of drying coffee grounds to powder, mixing the powder with a synthetic resin, injecting it into a mold to form the powder, and curing the molded body to demold it.

[0006] In a park golf club according to one embodiment, the head may have a porous structure such that internal pores improve shock dispersion and rebound force.

[0007] In a park golf club according to one embodiment, the coffee grounds powder has an average particle diameter in the range of 50 to 500 micrometers, and the relative standard deviation of the particle size distribution can be homogenized to 10% or less.

[0008] In a park golf club according to one embodiment, a reinforcing plate for reinforcing shock absorption and rebound force may be attached to the front of the head, and a weight adjustment plate for adjusting the center of gravity may be attached to the lower part of the head.

[0009] In a park golf club according to one embodiment, the head includes a shaft coupling portion for coupling the shaft, and the angle of inclination of the shaft coupling portion relative to the ground can be adjusted to suit the user's body type. Effects of the invention

[0010] The park golf club of the present invention is equipped with a head molded from a composite material comprising coffee grounds powder and synthetic resin, thereby simultaneously ensuring material diversity and eco-friendliness.

[0011] The park golf club of the present invention is manufactured through a process of drying coffee grounds to powder, mixing the powder with synthetic resin, injecting the mixture into a mold to form the product, and curing the molded body to demold it, thereby enabling the production of a product of uniform quality suitable for mass production.

[0012] The park golf club of the present invention can have its impact dispersion and rebound force improved by having a porous structure in which the head includes internal pores.

[0013] The park golf club of the present invention has a uniform average particle diameter and particle size distribution of coffee grounds powder, resulting in excellent mechanical properties and durability of the head.

[0014] The park golf club of the present invention has a reinforcing plate attached to the front of the head and a weight adjustment plate attached to the bottom, thereby facilitating the adjustment of shock absorption, rebound force, and center of gravity.

[0015] The park golf club of the present invention allows the angle of the shaft joint to be adjusted to fit the user's body type, thereby improving user customization.

[0016] Such effects are not limited to those described in the present invention and also include effects that a person skilled in the art can deduce from the present invention. Brief explanation of the drawing

[0017] FIG. 1 is a perspective view of a park golf club according to one embodiment. FIG. 2 is an exploded view of a park golf club according to one embodiment. FIG. 3 illustrates a park golf club head according to one embodiment. Specific details for implementing the invention

[0018] Specific structural or functional descriptions of the embodiments are disclosed for illustrative purposes only and may be modified and implemented in various forms. Accordingly, actual implementations are not limited to the specific embodiments disclosed, and the scope of this specification includes modifications, equivalents, or substitutions included in the technical concept described by the embodiments.

[0019] Terms such as "first" or "second" may be used to describe various components, but these terms should be interpreted solely for the purpose of distinguishing one component from another. For example, the first component may be named the second component, and similarly, the second component may be named the first component.

[0020] When it is stated that a component is "connected" to another component, it should be understood that it may be directly connected to or joined to that other component, or that there may be other components in between.

[0021] The singular expression includes the plural expression unless the context clearly indicates otherwise. In this specification, terms such as “comprising” or “having” are intended to specify the existence of the described features, numbers, steps, actions, components, parts, or combinations thereof, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0022] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this specification.

[0023] Hereinafter, embodiments will be described in detail with reference to the attached drawings. In the description with reference to the attached drawings, identical components are given the same reference numeral regardless of the drawing number, and redundant descriptions thereof will be omitted.

[0024] FIG. 1 is a perspective view of a park golf club (1) according to one embodiment.

[0025] FIG. 2 is an exploded view of a park golf club (1) according to one embodiment.

[0026] FIG. 3 illustrates a park golf club head (100) according to one embodiment.

[0027] According to some embodiments, a park golf club (1) may include a head (100) formed from a composite material comprising coffee grounds powder and a synthetic resin. The head (100) of the park golf club (1) may be formed by mixing coffee grounds powder and a synthetic resin, injecting the mixture into a mold, and then curing it. The coffee grounds powder may be ground to a range of 50 to 500 micrometers in average particle diameter. The synthetic resin may be selected from epoxy resin, polyurethane resin, etc., and may be uniformly mixed with the coffee grounds powder. The mixed composite material may be filled using vacuum injection or a vibrating table to minimize air bubbles within the mold. The molded head (100) may be cured through a room temperature or heat curing process. After curing, the head (100) may be separated from the mold and its external shape may be precisely finished through CNC machining. A coating layer providing waterproof and UV protection may be formed on the surface of the head (100). The head (100) may include a porous structure inside to improve shock dispersion and rebound force. The head (100) may additionally include natural fiber reinforcement, fine glass fiber, weather-resistant additives, and antibacterial or deodorizing components. The head (100) may have a recyclable structure that can be crushed after use and fed into a re-molding process. A carbon fiber plate with a thickness of 6 to 8 mm may be attached to the front of the head (100) using epoxy adhesive and a fastener (104). A weight adjustment plate (105) having a plurality of fastening grooves may be attached to the bottom of the head (100) so that its position can be changed forward and backward. A bulkhead structure for weight distribution may be formed inside the head (100). The acoustic properties of the head (100) may be controlled to reduce impact noise when hitting the ball. The head (100) may be designed to be replaceable by being coupled to the shaft (120) with a quick-release structure. The head (100) can have improved adhesion to synthetic resin and moisture resistance through degreasing or carbonization treatment of the coffee grounds powder. The head (100) may include a weather-resistant additive to prevent deformation due to changes in moisture and temperature.The head (100) can contribute to reducing environmental impact by using eco-friendly materials. The head (100) can be molded and automated post-processing applied to make it suitable for mass production processes.

[0028] In some embodiments of the present invention, the park golf club (1) may include a shaft (120) that is coupled to a head (100). The shaft (120) may be inserted into and fastened to a shaft coupling portion (103) of the head (100). The shaft coupling portion (103) may adjust the angle of inclination relative to the ground to suit the user's body type. The shaft (120) may be manufactured in a cylindrical structure, and the end portion may be rounded. The shaft (120) may be formed from various materials such as aluminum, carbon composite material, and stainless steel. The shaft (120) and the head (100) may be coupled so that they can be detached and replaced using a bolt, a fastener (104), a quick-release structure, etc. The length of the shaft (120) may be provided in various specifications to suit the user's height and body type. The shaft (120) may be designed to maintain coupling rigidity even with repeated fastening and unfastening. The shaft (120) may include a lie angle adjustment mechanism at the connection part (103) with the head (100) to allow for angle adjustment suitable for the user's posture. The shaft (120) may have an anti-slip treatment applied to the grip portion.

[0029] In some embodiments of the present invention, the composite head (100) may be molded into a composite structure comprising coffee grounds powder and a synthetic resin. The composite head (100) may be molded by mixing the coffee grounds powder and the synthetic resin and then injecting the mixture into a mold. The coffee grounds powder may undergo drying and grinding processes to adjust the average particle diameter to a range of 50 to 500 micrometers. The synthetic resin may be selected from epoxy resin, polyurethane resin, etc., and may be uniformly mixed with the coffee grounds powder. The mixed composite may be filled using vacuum injection or a vibrating table to minimize air bubbles within the mold. The molded composite head (100) may be cured at room temperature or through a heat curing process. Once cured, the composite head (100) may be separated from the mold and its external shape may be precisely finished through CNC machining. A coating layer providing waterproofing and UV protection may be formed on the surface of the composite head (100). The composite head (100) may include a porous structure inside to improve shock dispersion and repulsion. The composite head (100) may additionally include natural fiber reinforcement, fine glass fiber, weather-resistant additives, antibacterial or deodorizing components. The composite head (100) may have a recyclable structure that allows it to be crushed after use and fed into a remolding process. The composite head (100) may be designed to be replaceable by being combined with a shaft (120) via a quick-release structure.

[0030] According to some embodiments, the composite head (100) can be designed to simultaneously consider the striking performance, durability, and environmental sustainability of the park golf club (1). The composite head (100) may have a reinforcing plate attached to the front to increase shock absorption and rebound force. The composite head (100) may include natural fiber or fine glass fiber reinforcement to improve durability. The composite head (100) may contribute to resource recycling and reduction of environmental impact by utilizing the eco-friendly properties of coffee grounds powder. The internal structure of the composite head (100) may be designed so that no deformation or cracking occurs even with repeated striking. The composite head (100) may be subjected to mold forming and automated post-processing to be suitable for mass production processes.

[0031] According to some embodiments, the composite head (100) can be manufactured through a process of drying coffee grounds to powder, mixing the powder with synthetic resin, injecting it into a mold to form the mold, and curing and demolding the molded body. After recovery, the coffee grounds can be dried for 3 to 5 days by natural drying or hot air drying. The dried coffee grounds can be ground into powder using a fine grinding device and the particle size can be uniformly selected through a sieve. The synthetic resin can be prepared together with a curing agent and mixed with the coffee ground powder. During the mixing process, stirring conditions can be adjusted to control viscosity and minimize bubbles. The mixed material can be injected into a metal outer mold and a silicone mold structure. During injection, a vacuum state or a vibrating table can be used to suppress bubble generation. The molded body can be cured within the mold at room temperature or by a heat curing method. Once curing is complete, the molded body can be carefully separated from the mold to prevent surface damage. The demolded molded body can be flattened, corner rounded, and dimensional precision corrected through CNC machining.

[0032] In some embodiments of the present invention, the coffee grounds powder may have an average particle diameter in the range of 50 to 500 micrometers and may be homogenized so that the relative standard deviation of the particle size distribution is 10% or less. The particle size of the coffee grounds powder may be adjusted to a range of 50 to 500 micrometers through fine grinding and sieving processes. The relative standard deviation of the particle size distribution may be managed to be 10% or less by optimizing the sieve specifications and grinding conditions. A uniform particle size distribution can improve flowability during mold injection and the surface quality of the molded body.

[0033] According to some embodiments, coffee grounds powder can contribute to recycling and resource circulation as an eco-friendly material. Coffee grounds powder can reduce waste generation through the recycling of by-products from the coffee industry. Coffee grounds powder can provide biodegradability and carbon reduction effects. Coffee grounds powder can reduce environmental damage compared to existing wood materials.

[0034] According to some embodiments, the synthetic resin may be selected as an epoxy resin, a polyurethane resin, etc., for bonding with coffee grounds powder. The synthetic resin may be selected considering the adhesion and curing characteristics with the coffee grounds powder. The epoxy resin can provide high mechanical strength when mixed with a curing agent. The polyurethane resin can impart shock absorption and flexibility.

[0035] In some embodiments of the present invention, the synthetic resin is uniformly mixed with coffee grounds powder to improve the mechanical strength and durability of the composite material. The dispersibility of the synthetic resin can be enhanced by controlling the viscosity when mixed with the coffee grounds powder. The mixed composite material can be cured within a mold to form an integrated structure. Uniform mixing can increase the strength, durability, and impact resistance of the molded article.

[0036] In some embodiments of the present invention, the composite head (100) may have a smooth and uniform shape on its surface during the mold forming process. The surface roughness of the mold may be processed to 0.8 to 0.05 micrometers or less to ensure smoothness of the surface of the molded body. Vacuum injection and bubble removal processes may minimize surface defects. After molding, CNC finishing may be performed to improve the precision of the external shape.

[0037] According to some embodiments, the molded composite head (100) can maintain appearance quality and dimensional accuracy. The molded body can achieve an appearance with a harmonious balance of curved and flat surfaces by accurately replicating the detailed shape of the mold. Dimensional accuracy can be managed through CNC machining and quality inspection. Appearance quality can be maintained for a long period by applying a waterproof and UV coating layer.

[0038] In some embodiments of the present invention, the composite head (100) forms the overall appearance of the park golf club (1) and can be implemented in a form that combines curved surfaces and flat surfaces as shown in the drawings. The composite head (100) can be designed with a structure in which the upper part is a curved surface and the lower part is a flat surface. The curved surface helps disperse impact when hitting the ball, and the flat surface can provide contact stability with the ground. As shown in the perspective view of Drawing 1, the appearance can be clearly distinguished into the head (100), the shaft connection part (103), the front, the bottom, and the side.

[0039] According to some embodiments, the composite head (100) may be formed with a structure in which the upper part is round and the lower part is flat, as can be seen in the perspective view. The upper curved surface may induce energy dispersion when hitting the ball. The lower flat surface may minimize friction with the ground during a swing. The overall shape may be ergonomically designed to fit the user's swing trajectory.

[0040] In some embodiments of the present invention, the composite head (100) can be designed according to the function of each part by clearly partitioning the upper, lower, front, and rear sections. The upper section may be responsible for shock dispersion with a curved structure. The lower section may contribute to stabilizing the center of gravity with a flat structure. A reinforcing plate may be attached to the front section to increase repulsion force and durability. The rear section may be connected to the shaft coupling section (103) to ensure fastening rigidity.

[0041] According to some embodiments, the composite head (100) can be processed so that the surface texture, color, and touch can enhance the user's visual and tactile satisfaction. The surface texture can be controlled according to the mold roughness and CNC machining conditions. The color can be achieved through the natural color of coffee grounds powder or a coloring agent. The touch can be finished smoothly and uniformly by applying a waterproof and UV coating layer.

[0042] According to some embodiments, the composite head (100) can perform various functions such as shock dispersion, weight distribution, and mounting of reinforcing parts through its internal structure. A porous structure is formed internally to absorb and disperse shock energy. Internal ribs or bulkhead structures can adjust the swing balance by evenly distributing weight. A mounting interface may be provided internally to allow for the attachment of additional parts, such as reinforcing plates and weight adjustment plates (105).

[0043] According to some embodiments, the head (100) may have a porous structure such that internal pores enhance impact dispersion and repulsion. The porous structure may be uniformly distributed internally in the form of microcells. The porosity may be set by adjusting additives and stirring conditions during the molding process. The porous structure may increase repulsion by providing an energy absorption path upon impact.

[0044] According to some embodiments, the composite head (100) may have an internal mounting interface formed therein so that additional parts, such as a reinforcing plate and a weight adjustment plate (105), can be attached. The mounting interface may be implemented as a screw thread, a fastener (104), an insertion groove, etc. The reinforcing plate may be aligned on the front of the head (100) and then fastened with epoxy adhesive and a bolt. The weight adjustment plate (105) may be installed so that its front and rear position can be adjusted through a plurality of fastening grooves on the lower part.

[0045] In some embodiments of the present invention, the composite head (100) may have a recyclable structure that can be crushed after use and fed into a remolding process. The composite head (100) may be crushed through a crushing device after use. The crushed material may be remixed with synthetic resin in a remolding process to produce a new head (100). The recyclable structure may be designed to be suitable for a repetitive circulation process.

[0046] According to some embodiments, the shaft (120) and the coupling part (103) may include a structure that connects the head (100) of the park golf club (1) and the shaft (120). The shaft (120) and the coupling part (103) may be connected in such a way that the shaft coupling part (103) of the head (100) and the end of the shaft (120) are inserted and fastened to each other. The shaft (120) and the coupling part (103) may include various coupling structures such as a coupling hole, a fastener (104), or a quick-release mechanism. The shaft (120) and the coupling part (103) may be designed to fix or adjust the relative position and angle of the head (100) and the shaft (120). The shaft (120) and the coupling part (103) may be made of a highly durable material so that the coupling strength is maintained even with repeated fastening and unfastening.

[0047] According to some embodiments, the shaft (120) and the coupling part (103) may be designed in various variations considering the user's body type, purpose of use, and ease of maintenance. The shaft (120) and the coupling part (103) may be designed to allow adjustment of length, angle, center of gravity, etc., according to the user's height, arm length, and swing posture. The shaft (120) and the coupling part (103) may be implemented as a replaceable or modular structure and may be compatible with various shafts (120). The shaft (120) and the coupling part (103) may include a structure that is easy to separate and assemble to facilitate maintenance and parts replacement. The shaft (120) and the coupling part (103) may use standardized parts or adapters considering economic efficiency. The shaft (120) may include a grip part (121).

[0048] According to some embodiments, the shaft coupling portion (103) may include a structure for firmly connecting the head (100) and the shaft (120). The shaft coupling portion (103) may be designed so that the coupling hole of the head (100) and the end of the shaft (120) are precisely engaged. The shaft coupling portion (103) may include a fastener (104), a bolt, a screw, a pin, or a press-fit fastener (104) to increase the coupling rigidity. The shaft coupling portion (103) may prevent the shaft (120) from detaching or shaking through the fastening direction, insertion depth, and anti-rotation structure. The shaft coupling portion (103) may be made of a wear-resistant material, such as metal or reinforced plastic, so that the durability of the coupling portion (103) can be maintained even with repeated fastening and unfastening.

[0049] According to some embodiments, the shaft coupling portion (103) may include a coupling hole for coupling the shaft (120). The coupling hole of the shaft coupling portion (103) may be formed on the upper or side of the head (100). The coupling hole may be machined into a cylindrical, elliptical, or polygonal cross-section so that the end of the shaft (120) can be inserted. The inner diameter of the coupling hole may be designed to precisely match the outer diameter of the shaft (120). The depth of the coupling hole may be adjusted according to the insertion length of the shaft (120).

[0050] According to some embodiments, the coupling hole of the shaft coupling portion (103) may be designed considering the insertion direction and fastening direction of the shaft (120). The angle of the coupling hole may be adjusted so that the shaft (120) can be inserted in a vertical or inclined direction. The fastening direction of the coupling hole may have threads, grooves, or protrusions formed to prevent rotation or detachment of the shaft (120). The fastening direction of the coupling hole may engage with the fastening member (104) of the shaft (120) to increase the fixing force.

[0051] In some embodiments of the present invention, the coupling hole of the shaft coupling portion (103) may include a fastener (104) to prevent rotation or detachment of the shaft (120). A key groove or protrusion may be formed in the coupling hole to prevent rotation of the shaft (120). A bolt, pin, or press-fit fastener (104) to prevent detachment of the shaft (120) may be inserted into the coupling hole. The fastener (104) of the coupling hole may be made of a wear-resistant material so that the coupling strength can be maintained even with repeated use.

[0052] In some embodiments of the present invention, the shaft coupling portion (103) may include a mechanism for adjusting the lie angle. The lie angle adjustment mechanism of the shaft coupling portion (103) may include a pivot or a hinge structure at the coupling portion (103) of the head (100) and the shaft (120). The lie angle adjustment mechanism may finely adjust the angle through a fastener (104), an adjustment bolt, or a ratchet mechanism. The lie angle adjustment mechanism may include a locking device so that the angle can be fixed after adjustment.

[0053] In some embodiments of the present invention, the lie angle adjustment mechanism of the shaft coupling part (103) may be designed to finely adjust the angle between the head (100) and the shaft (120) according to the user's posture or swing style. The lie angle adjustment mechanism may adjust the angle in 1-degree increments according to the user's height, arm length, and swing trajectory. The lie angle adjustment mechanism may be designed so that the holding force does not decrease even when the angle is repeatedly changed within the adjustment range. The lie angle adjustment mechanism may be equipped with a fastener (104) and a locking structure so that the coupling rigidity of the head (100) and the shaft (120) is maintained even after adjustment.

[0054] In some embodiments of the present invention, the shaft coupling portion (103) may include a bolt, screw, pin, or press-fit fastener (104) to ensure fastening rigidity. The shaft coupling portion (103) may secure the shaft (120) and the head (100) by a bolt fastening method. The shaft coupling portion (103) may be fastened with a screw after inserting the shaft (120) into a coupling hole with threads. The shaft coupling portion (103) may prevent rotation and detachment of the shaft (120) by using a pin or press-fit fastener (104). The shaft coupling portion (103) may increase fastening rigidity by optimizing the material and shape of the fastener (104).

[0055] In some embodiments of the present invention, the shaft coupling portion (103) may be selected in a material and structure so that the coupling strength is maintained even with repeated fastening and unfastening. The shaft coupling portion (103) may be made of a durable material such as a wear-resistant metal, reinforced plastic, or composite material. The shaft coupling portion (103) may be surface-hardened or coated to prevent wear of the fastener (104). The shaft coupling portion (103) may be reinforced in structure so that deformation or damage to the coupling portion (103) does not occur even during repeated fastening and unfastening.

[0056] According to some embodiments, the angle of the shaft coupling portion (103) can be adjusted to suit the user's body type, such as height, arm length, and swing posture. The angle can be finely adjusted in 1-degree increments between the head (100) and the shaft (120) according to the user's height.

[0057] According to some embodiments, the angle of the shaft coupling part (103) may be set to an adjustment range based on ergonomic criteria. The angle of the shaft may be designed to be adjustable within a range of 5 to 20 degrees based on ergonomic analysis. The angle of the shaft coupling part may be set to an adjustment range to minimize the user's swing posture and fatigue.

[0058] In some embodiments of the present invention, the angle of inclination of the shaft coupling part (103) relative to the ground may be adjustable to suit the user's body type. The inclination of the shaft coupling part (103) relative to the ground may be adjusted within a range of 5 to 20 degrees depending on the user's height and swing posture. The inclination adjustment of the shaft coupling part (103) may be implemented through a pivot axis or a hinge structure. The inclination adjustment of the shaft coupling part (103) may be finely adjusted using an adjustment bolt or a ratchet mechanism.

[0059] According to some embodiments, the shaft coupling portion (103) may be selected in a material and structure so that the durability of the coupling portion (103) can be maintained even with repeated fastening and unfastening. The shaft coupling portion (103) may be surface-hardened or coated to prevent wear of the fastener (104). The shaft coupling portion (103) may be made of a wear-resistant material so that the coupling strength can be maintained even with repeated fastening and unfastening. The shaft coupling portion (103) may be reinforced in structure so that deformation or damage to the coupling portion (103) does not occur.

[0060] According to some embodiments, the shaft (120) and the coupling part (103) may be designed to be replaceable and modular. The shaft (120) and the coupling part (103) may be implemented as a modular structure to facilitate easy separation and connection between the head (100) and the shaft (120). The shaft (120) and the coupling part (103) may include an adapter structure to be compatible with shafts (120) of various lengths, materials, or weights. The shaft (120) and the coupling part (103) may be designed so that the user can directly replace or upgrade parts. The shaft (120) and the coupling part (103) may apply a standardized coupling structure to facilitate maintenance and parts replacement.

[0061] In some embodiments of the present invention, the shaft (120) and the head (100) may be a replaceable park golf club (1) joined by a quick-release structure. The shaft (120) and the head (100) can be quickly separated and joined through a button-type quick-release mechanism. The shaft (120) and the head (100) may be designed to be replaceable without a separate tool by applying a quick-release structure. The shaft (120) and the head (100) may be made of a highly durable material so that the joint rigidity is maintained even with repeated replacement. The shaft (120) and the head (100) may be compatible with various shafts (120) through the quick-release structure. The shaft (120) and the head (100) may be a replaceable park golf club (1) joined by a quick-release structure.

[0062] In some embodiments of the present invention, the shaft coupling portion (103) may include a quick-release mechanism that allows for rapid separation and coupling without the need for a separate tool. The shaft coupling portion (103) may include a button, lever, or slide-type quick-release mechanism. The shaft coupling portion (103) may be ergonomically designed so that the user can easily perform separation and coupling. The shaft coupling portion (103) may be made of a highly durable material so that coupling rigidity is maintained even with repeated separation and coupling.

[0063] In some embodiments of the present invention, the shaft coupling portion (103) may be designed to be compatible with shafts (120) of various lengths and materials. The inner diameter of the shaft coupling portion (103) may be adjusted to be compatible with shafts (120) ranging in length from 80 cm to 90 cm. The shaft coupling portion (103) may include an adapter structure to be coupled with shafts (120) of various materials, such as aluminum, carbon, and natural wood. The shaft coupling portion (103) may selectively combine various shafts (120) according to the user's body type or preference.

[0064] In some embodiments of the present invention, the shaft coupling portion (103) may selectively use various types of shafts (120) by applying a standard specification or an adapter structure. The shaft coupling portion (103) may apply an inner diameter and a fastener (104) conforming to international standard specifications. The shaft coupling portion (103) may be designed to allow non-standard shafts (120) to be coupled using an adapter. The shaft coupling portion (103) may include a modular structure to facilitate the replacement and upgrading of various shafts (120).

[0065] In some embodiments of the present invention, the shaft coupling part (103) is designed to be easy to replace and maintain, thereby increasing economic efficiency. The shaft coupling part (103) allows for easy separation and assembly of parts, enabling the user to perform maintenance directly. The shaft coupling part (103) can reduce parts replacement costs by using standardized parts. The shaft coupling part (103) can reduce the frequency of maintenance even during long-term use by using a highly durable material.

[0066] According to some embodiments, the shaft coupling part (103) may be designed so that the user can perform maintenance directly by making it easy to separate and assemble parts. The shaft coupling part (103) may include a structure that allows separation and assembly without tools. The shaft coupling part (103) may be ergonomically designed so that the user can easily replace or upgrade parts. The shaft coupling part (103) may have a modular structure to facilitate maintenance and parts replacement.

[0067] According to some embodiments, user-customized design parameters can be set to allow various elements, such as the size, weight, balance, and manufacturing process linkage of the park golf club (1), to be adjusted to the user's physical condition and preferences. User-customized design parameters can select the specifications of each component of the park golf club (1) based on individual data such as the user's height, body type, muscle strength, and swing style. User-customized design parameters can be independently adjusted for detailed items such as the size and weight of the head (100), the length, diameter, lie angle, and center of gravity position of the shaft (120). For example, user-customized design parameters can be implemented in conjunction with mold design, composite material mixing ratio, the position of the weight adjustment plate (105), and the thickness of the reinforcement plate during the manufacturing stage. User-customized design parameters can be stored in a database as custom specifications in addition to standard specifications and utilized for repetitive production.

[0068] According to some embodiments, user-customized design parameters can be designed by comprehensively considering the performance, ease of use, durability, and environmental suitability of the park golf club (1). User-customized design parameters can be set based on performance indicators such as the rebound force, shock absorption force, hitting sound, moisture resistance, and weather resistance of the park golf club (1). User-customized design parameters can be linked to durability enhancement elements such as the weight distribution structure, application of reinforcement materials, and surface coating method of the park golf club (1). User-customized design parameters can adjust the scope of application of eco-friendly materials such as coffee grounds powder, synthetic resin, natural fiber reinforcement, and weather-resistant additives. For example, user-customized design parameters may include environmental suitability items such as antibacterial components, deodorizing components, and recycling structures.

[0069] In some embodiments of the present invention, the park golf club (1) may have the size and weight of the head (100) and the length and diameter of the shaft (120) set to various ranges according to the user's height, body type, and muscle strength. The size of the head (100) of the park golf club (1) may be selected, for example, from 80 mm to 120 mm, and the weight may be selected within a range from 250 g to 400 g. The length of the shaft (120) may be adjusted from 80 cm to 90 cm and the diameter from 12 mm to 16 mm according to the user's height. The weight of the head (100) may be finely adjusted according to the application position and thickness of the internal weight adjustment plate (105). The length and diameter of the shaft (120) may be custom-made through cutting and processing processes during the manufacturing stage.

[0070] According to some embodiments, the size and weight of the park golf club (1) may be manufactured with custom specifications in addition to standard specifications. The size and weight of the park golf club (1) may be based on the International Park Golf Federation standards, but may also be produced with non-standard specifications according to the user's requirements. For custom specifications, the mold design, composite material composition, weight adjustment plate (105) specifications, etc., may be automatically changed according to user data entered at the time of order. The custom size and weight are recorded in a production history management system and can be quickly applied when the same user places a reorder.

[0071] In some embodiments of the present invention, the head (100) of the park golf club (1) may include a shaft coupling portion (103) for coupling a shaft (120). The shaft coupling portion (103) may be formed on the upper or side of the head (100). The shaft coupling portion (103) may be machined into a cylindrical or polygonal cross-section so that the end of the shaft (120) can be inserted. The inner diameter of the shaft coupling portion (103) may be designed to precisely match the outer diameter of the shaft (120). The shaft coupling portion (103) may include a fastener (104), a bolt, a pin, or a press-fit fastener (104) to increase coupling rigidity.

[0072] In some embodiments of the present invention, the park golf club (1) may be designed to adjust the center of gravity and balance according to the user's swing posture, hand position, and force distribution. The center of gravity of the park golf club (1) may be set by adjusting the position of the lower part, front part, or shaft coupling part (103) of the head (100). The center of gravity may be adjusted in various ways, such as changing the position of the weight adjustment plate (105), designing the internal rib structure, or adjusting the thickness of the reinforcement plate. For example, the center of gravity may be adjusted by attaching the weight adjustment plate (105) to the lower part of the head (100) so that it aligns with the rotation axis of the wrist during a swing. The center of gravity adjustment may be designed considering the rigidity and durability of the fastener (104) so ​​that no deformation occurs even with repeated use.

[0073] According to some embodiments, a weight adjustment plate (105) for adjusting the center of gravity may be attached to the lower part of the head (100) of a park golf club (1). The weight adjustment plate (105) may be attached to the lower part of the head (100) using a bolt, screw, or press-fit fastener (104). The weight adjustment plate (105) may be made of metal or an elastic plate with a thickness of 2 mm to 8 mm. The weight adjustment plate (105) has a plurality of fastening grooves and can finely adjust the center of gravity by changing its front and rear position. The weight adjustment plate (105) is designed to be detachable so that the user can replace it or change its position directly.

[0074] In some embodiments of the present invention, the park golf club (1) can optimize ergonomic balance by adjusting the position, fastening method, internal structure, etc. of the weight adjustment plate (105). The position of the weight adjustment plate (105) can be selectively placed at the front, rear, or center of the head (100). The fastening method of the weight adjustment plate (105) can be implemented in various ways, such as bolt fastening, sliding insertion, magnetic attachment, etc. The internal structure can optimize weight distribution by inserting ribs, partitions, reinforcing materials, etc. The ergonomic balance can be customized according to the results of analyzing the user's swing data.

[0075] In some embodiments of the present invention, user-customized design parameters can be implemented in conjunction with mold design, composite material composition, processing, and parts assembly during the manufacturing stage. Mold design can be automatically generated as 3D CAD data according to the user's customized size, shape, and center of gravity location. Composite material composition can be customized by adjusting the ratios of coffee grounds powder, synthetic resin, natural fiber reinforcement, weather-resistant additives, etc. Processing processes can be automated for detailed operations such as CNC cutting, surface polishing, and edge rounding according to customized specifications. Parts assembly can be customized by applying the position and fastening method of each part, such as the shaft coupling part (103), weight adjustment plate (105), and reinforcement plate.

[0076] According to some embodiments, the specifications and assembly sequence of each part can be adjusted according to customized parameters such as size, weight, and balance during the manufacturing stage. During the manufacturing stage, the specifications of the head (100), shaft (120), weight adjustment plate (105), and reinforcement plate can be automatically assigned according to order data. The assembly sequence of each part can be subdivided according to customized parameters into assembly of the shaft coupling part (103), attachment of the weight adjustment plate (105), attachment of the reinforcement plate, surface coating, etc. The assembly sequence and process conditions can be controlled in real time by a production management system.

[0077] According to some embodiments, the location and specifications of key components, such as the shaft coupling part (103), weight adjustment plate (105), and reinforcement plate, can be selectively applied during the manufacturing stage to meet the user's requirements. The coupling angle and insertion depth of the shaft coupling part (103) can be adjusted according to the user's swing posture and hand position. The thickness, material, and location of the weight adjustment plate (105) can be selected according to the user's muscle strength and swing balance. The thickness, material, and fastening method of the reinforcement plate can be customized according to the user's preferences, such as shock absorption, rebound force, and hitting sound. The location and specifications of the key components can be linked with production history data to enable quality control and tracking.

[0078] FIG. 2 is an exploded view of a park golf club (1) according to one embodiment.

[0079] According to some embodiments, the head (100) reinforcement structure and center of gravity adjustment can be designed to improve the durability, shock absorption, rebound force, weight distribution, user-customized balance, and durability for repeated use of the park golf club (1). The head (100) reinforcement structure and center of gravity adjustment can implement various mechanical properties by arranging a reinforcement plate, a weight adjustment plate (105), and a rib structure in the front, bottom, and inside of the head (100), respectively. The head (100) reinforcement structure and center of gravity adjustment can apply a carbon fiber plate to the front reinforcement plate (102) to improve shock absorption. The head (100) reinforcement structure and center of gravity adjustment can adjust the position of the lower weight adjustment plate (105) forward and backward for weight distribution. The head (100) reinforcement structure and center of gravity adjustment can suppress deformation during repeated use through an internal rib structure. The head (100) reinforcement structure and center of gravity adjustment can adjust the center of gravity position and balance to match the user's swing style and body type. The head (100) reinforcement structure and center of gravity adjustment can utilize a combination of fasteners (104) and adhesive to maintain durability even under repeated impacts.

[0080] In some embodiments of the present invention, a reinforcing plate may be attached to the front surface of the head (100) to reinforce shock absorption and rebound force. The reinforcing plate may be designed to be in close contact with the front surface of the head (100). The reinforcing plate may be formed from a carbon fiber plate with a thickness of 6 mm to 8 mm. The reinforcing plate may be detachably attached using epoxy adhesive and a bolt fastener (104). The reinforcing plate can prevent cracking of the head (100) by dispersing energy when an impact is applied. The reinforcing plate can increase the distance of the ball when struck by increasing the rebound force. The reinforcing plate can adjust the acoustic characteristics of the sound of the ball being struck.

[0081] According to some embodiments, a weight adjustment plate (105) for adjusting the center of gravity may be attached to the lower part of the head (100). The weight adjustment plate (105) may be attached flatly to the lower part of the head (100). The weight adjustment plate (105) has a plurality of fastening grooves, and the center of gravity can be adjusted by changing the fastening position forward and backward. The weight adjustment plate (105) may be made of metal or an elastic plate. The weight adjustment plate (105) can be repeatedly attached and detached and positioned through the fastening member (104). The weight adjustment plate (105) can finely adjust the weight distribution to match the user's swing balance. The weight adjustment plate (105) can increase durability by reinforcing the lower rigidity of the head (100).

[0082] In some embodiments of the present invention, the head (100) reinforcement structure and center of gravity adjustment may include a reinforcement plate, a weight adjustment plate (105), an internal rib structure, a fastener (104), and a combination of various fastening methods. The reinforcement plate may be placed on the front of the head (100), the weight adjustment plate (105) on the bottom, and the internal rib structure inside the head (100). The internal rib structure may be designed in the form of a bulkhead to evenly distribute weight. The fastener (104) may be applied in various ways, such as a bolt, a pin, or a press-fit fastener (104). A combination of the fastener (104) and an adhesive may increase the detachment and retention force of the reinforcement plate and the weight adjustment plate (105). Various fastening methods may maintain fastening rigidity even during repeated use. The internal rib structure may suppress deformation of the head (100) and, in conjunction with the weight adjustment plate (105), increase the precision of the center of gravity adjustment.

[0083] In some embodiments of the present invention, the head (100) reinforcement structure and center of gravity adjustment can be customized according to the user's swing style, body type, and preferences. The head (100) reinforcement structure and center of gravity adjustment can select the specifications of the reinforcement plate and the weight adjustment plate (105) based on data such as the user's height, muscle strength, and swing speed. The head (100) reinforcement structure and center of gravity adjustment can be independently adjusted for detailed items such as the position of the weight adjustment plate (105), the thickness of the reinforcement plate, and the design of the internal rib structure. For example, the head (100) reinforcement structure and center of gravity adjustment can be produced with customized specifications based on user information stored in an on-demand database. The head (100) reinforcement structure and center of gravity adjustment can reproduce the same balance and center of gravity upon reordering by a repeat user.

[0084] According to some embodiments, the head (100) reinforcement structure and center of gravity adjustment can serve to comprehensively improve the performance, ease of use, durability, and environmental suitability of the park golf club (1). The head (100) reinforcement structure and center of gravity adjustment can be designed based on performance indicators such as shock absorption, rebound force, weight distribution, and durability. The head (100) reinforcement structure and center of gravity adjustment can be linked to environmental suitability factors such as the application of reinforcement materials, surface coating, and recycling structures. For example, the head (100) reinforcement structure and center of gravity adjustment can adjust the range of application of eco-friendly materials such as coffee grounds powder, synthetic resin, natural fiber reinforcement, and weather-resistant additives. The head (100) reinforcement structure and center of gravity adjustment can be designed as a structure that allows for crushing and remolding after use.

[0085] In some embodiments of the present invention, a reinforcing plate may be attached to the front surface of the head (100) to reinforce shock absorption and repulsion. The reinforcing plate may be positioned to be in direct contact with the front surface of the head (100). The reinforcing plate may be formed into a curved or flat shape to match the front shape of the head (100). The reinforcing plate may cover the entire front surface of the head (100) or be partially attached only to the area where the impact is concentrated. When the reinforcing plate is attached to the front surface of the head (100), it may be designed to be in close contact so that no gap occurs between the head (100) and the reinforcing plate. A fastener (104) and an adhesive may be used together so that the position of the reinforcing plate does not change even under repeated impacts while attached to the front surface of the head (100).

[0086] According to some embodiments, the reinforcing plate may be designed to be in close contact with the front surface of the head (100). The reinforcing plate may be machined into a three-dimensional curved surface to match the curvature of the front surface of the head (100). A groove or guide for inserting the reinforcing plate may be formed on the front surface of the head (100) to ensure close contact of the reinforcing plate. The reinforcing plate may be fixed to the front surface of the head (100) through a compression process after applying epoxy adhesive. The close contact status of the reinforcing plate may be verified visually and mechanically during the quality inspection stage.

[0087] In some embodiments of the present invention, the reinforcing plate may be formed from a carbon fiber plate with a thickness of 6 mm to 8 mm. The reinforcing plate may be manufactured by laminating carbon fibers in the form of continuous yarns or short fibers. The thickness of the reinforcing plate may be custom-produced in various specifications, such as 6 mm, 7 mm, and 8 mm. The reinforcing plate may be manufactured by a thermosetting molding method using epoxy resin and carbon fiber prepreg. The thickness of the reinforcing plate may be determined considering the effects of dispersing impact from hitting the ball and increasing rebound force.

[0088] According to some embodiments, the reinforcing plate may employ a carbon fiber plate to ensure high strength and durability. Compared to a metal plate of the same thickness, the carbon fiber plate is lighter in weight and has excellent tensile strength and impact resistance. The carbon fiber plate is suitable for long-term use as it has minimal deformation even under repeated impacts. The carbon fiber plate has excellent moisture resistance and weather resistance, so there is minimal performance degradation even with changes in the external environment. The carbon fiber plate has high bonding strength with epoxy resin, so it can be stably attached to the front surface of the head (100).

[0089] In some embodiments of the present invention, the thickness of the reinforcing plate may be set to a range of about 6 mm to 8 mm. The thickness of the reinforcing plate is designed to withstand the maximum impact load generated during striking. A reinforcing plate with a thickness of 6 mm may be applied when lightweighting is required. A reinforcing plate with a thickness of 8 mm may be applied when increased shock absorption and rebound force are required. The thickness of the reinforcing plate may be optimized by taking into account the overall weight and balance of the head (100).

[0090] In some embodiments of the present invention, the reinforcing plate can be designed to simultaneously secure lightness and high rigidity. The reinforcing plate can provide sufficient rigidity with a minimum thickness by utilizing the high strength characteristics of carbon fiber. The reinforcing plate can increase rigidity while reducing weight by applying a honeycomb structure or a multi-layer laminated structure internally. The lightweighting of the reinforcing plate can contribute to the swing balance of the entire park golf club (1) and the reduction of user fatigue.

[0091] According to some embodiments, the reinforcing plate may be detachably attached using epoxy adhesive and a bolt fastener (104). The reinforcing plate may be fixed by applying epoxy adhesive to the front surface of the head (100) and then inserting a bolt or fastener (104) at a designated location. The fastener (104) of the reinforcing plate may be coupled with a nut or insert embedded inside the head (100). The reinforcing plate may be detached through a process of bolt removal and adhesive removal. The fastening structure of the reinforcing plate is designed to maintain fastening rigidity even with repeated disassembly and assembly.

[0092] According to some embodiments, the reinforcing plate can be bonded to the front surface of the head (100) by applying epoxy adhesive. The epoxy adhesive can increase bonding strength by filling the fine gap between the reinforcing plate and the front surface of the head (100). The epoxy adhesive can provide high shear strength and impact resistance after curing. The curing time of the epoxy adhesive can be controlled according to working temperature and humidity conditions. The epoxy adhesive can be separated using heat or a solvent when the reinforcing plate is detached.

[0093] In some embodiments of the present invention, the reinforcing plate may be fixed at a designated location on the front of the head (100) using a bolt or a fastener (104). The bolt holes of the reinforcing plate may be formed at left-right symmetrical locations on the front of the head (100). The fastener (104) of the reinforcing plate may be coupled with a metal insert inserted inside the head (100). The bolt fastening location of the reinforcing plate may be positioned around the area where the impact of the ball strike is concentrated. The fastener (104) of the reinforcing plate may be designed so that no damage to the threads occurs even with repeated fastening and unfastening.

[0094] According to some embodiments, the reinforcing plate may be designed to be detachable for maintenance and replacement. The reinforcing plate may be detached through a process of bolt removal and adhesive separation. The reinforcing plate may be manufactured to standardized specifications so that it can be quickly replaced in the event of damage or wear. The detachable structure of the reinforcing plate may be designed so that the user can disassemble and assemble it without the need for separate special tools. After the reinforcing plate is detached, the surface of the front of the head (100) can be checked for damage.

[0095] In some embodiments of the present invention, the reinforcing plate can prevent cracking of the head (100) by dispersing energy when an impact is applied. The reinforcing plate can relieve stress concentration inside the head (100) by dispersing the impact energy generated during hitting over a wide area. The reinforcing plate can suppress surface cracking or damage of the head (100) even with repeated hitting impacts. The reinforcing plate can improve the durability of the head (100) through its shock absorption properties.

[0096] In some embodiments of the present invention, the reinforcing plate can increase the distance of the ball upon impact by increasing the repulsive force. The reinforcing plate can efficiently repel energy upon impact by utilizing the high elastic modulus of carbon fiber. The magnitude of the repulsive force can be adjusted according to the thickness and laminated structure of the reinforcing plate. By increasing the repulsive force, the reinforcing plate can achieve a longer distance at the same swing speed.

[0097] According to some embodiments, the reinforcing plate can adjust the acoustic characteristics of the hitting sound. The reinforcing plate can amplify or attenuate sound in a specific frequency band by controlling vibrations generated during hitting. The pitch and duration of the hitting sound may vary depending on the material and thickness of the reinforcing plate. The reinforcing plate can implement a hitting sound preferred by the user by applying an acoustic tuning pattern internally.

[0098] In some embodiments of the present invention, the reinforcing plate can prevent cracking of the head (100) by dispersing energy when an impact is applied. The reinforcing plate can relieve stress concentration inside the head (100) by dispersing the impact energy generated during hitting over a wide area. The reinforcing plate can suppress surface cracking or damage of the head (100) even with repeated hitting impacts. The reinforcing plate can improve the durability of the head (100) through its shock absorption properties.

[0099] In some embodiments of the present invention, the reinforcing plate can increase the distance of the ball upon impact by increasing the repulsive force. The reinforcing plate can efficiently repel energy upon impact by utilizing the high elastic modulus of carbon fiber. The magnitude of the repulsive force can be adjusted according to the thickness and laminated structure of the reinforcing plate. By increasing the repulsive force, the reinforcing plate can achieve a longer distance at the same swing speed.

[0100] According to some embodiments, the reinforcing plate can adjust the acoustic characteristics of the hitting sound. The reinforcing plate can amplify or attenuate sound in a specific frequency band by controlling vibrations generated during hitting. The pitch and duration of the hitting sound may vary depending on the material and thickness of the reinforcing plate. The reinforcing plate can implement a hitting sound preferred by the user by applying an acoustic tuning pattern internally.

[0101] In some embodiments of the present invention, the lower weight adjustment plate (105) may be attached to the lower part of the head (100) to serve to adjust the center of gravity. The lower weight adjustment plate (105) may be positioned to make direct contact with the lower surface of the head (100). The lower weight adjustment plate (105) may be fixed to the lower part of the head (100) using a fastener (104). The lower weight adjustment plate (105) may be designed to be detachable or repositionable according to the user's requirements. The lower weight adjustment plate (105) may be used to move the center of gravity of the head (100) forward, backward, left, or right. The lower weight adjustment plate (105) may have a direct effect on the overall balance and swing characteristics of the head (100).

[0102] In some embodiments of the present invention, a lower weight adjustment plate (105) may be included as a key component for adjusting the overall balance and swing characteristics of the head (100). The lower weight adjustment plate (105) can adjust the rotational inertia and stability of the head (100) during a swing by changing the weight distribution of the head (100). The lower weight adjustment plate (105) may be applied for various purposes, such as adjusting swing balance, improving ball direction stability, and user-customized settings. The lower weight adjustment plate (105) may be integrated with the lower structure of the head (100) or implemented as a separate attachment structure.

[0103] According to some embodiments, the lower weight adjustment plate (105) may be formed from various materials such as a metal plate, a synthetic resin plate, or an elastic plate. The lower weight adjustment plate (105) may be made of a metal material such as stainless steel, aluminum, or brass. The lower weight adjustment plate (105) may be molded from a synthetic resin material such as polyurethane or epoxy. The lower weight adjustment plate (105) may be made of an elastic material such as rubber or silicone to add a shock absorption function. The selection of the material for the lower weight adjustment plate (105) may be determined by considering weight, durability, vibration absorption characteristics, etc.

[0104] According to some embodiments, the lower weight adjustment plate (105) may be fixed to a designated location on the lower part of the head (100) via a fastener (104). The lower weight adjustment plate (105) may be attached to the lower part of the head (100) using a fastener (104), such as a bolt, screw, or pin. The fastener (104) of the lower weight adjustment plate (105) may be aligned with an insertion hole or thread formed on the lower part of the head (100). The lower weight adjustment plate (105) may secure fastening rigidity by adjusting the tightening torque of the fastener (104). The lower weight adjustment plate (105) may be designed to minimize wear on the fastener (104) even with repeated fastening and unfastening.

[0105] According to some embodiments, the lower weight adjustment plate (105) may be designed to have a structure including a plurality of fastening grooves. The lower weight adjustment plate (105) may be formed as a flat or curved structure having two or more fastening grooves. The fastening grooves of the lower weight adjustment plate (105) may be machined into various shapes such as circular, elliptical, or slotted. The plurality of fastening grooves of the lower weight adjustment plate (105) may be arranged at regular intervals or asymmetrical intervals to increase the degree of freedom for position adjustment.

[0106] According to some embodiments, the fastening groove of the lower weight adjustment plate (105) may be arranged at a position corresponding to the lower part of the head (100). The fastening groove of the lower weight adjustment plate (105) may be designed to align with the insertion position of the fastening member (104) formed in the lower part of the head (100). The arrangement of the fastening groove of the lower weight adjustment plate (105) may be arranged along the width direction, length direction, or diagonal direction of the lower part of the head (100). The position of the fastening groove of the lower weight adjustment plate (105) may be determined by considering the center of gravity movement range and user convenience.

[0107] In some embodiments of the present invention, the lower weight adjustment plate (105) may include a hole or slot for inserting a fastener (104). The hole of the lower weight adjustment plate (105) may be designed with a diameter and depth to allow the insertion of a fastener (104), such as a bolt, screw, or pin. The slot of the lower weight adjustment plate (105) may allow for the positional movement of the fastener (104), thereby enabling fine positional adjustment. The hole or slot of the lower weight adjustment plate (105) may be reinforced with a structure to ensure fastening rigidity and durability for repeated use.

[0108] In some embodiments of the present invention, the lower weight adjustment plate (105) may be fixed at various positions by having a plurality of fastening grooves arranged at regular intervals. The plurality of fastening grooves of the lower weight adjustment plate (105) may be arranged continuously at regular intervals, such as 5 mm or 10 mm. The position of the lower weight adjustment plate (105) may be changed by selectively inserting a fastening member (104) into each fastening groove. The arrangement of the fastening grooves of the lower weight adjustment plate (105) may be designed so that the user can finely adjust the center of gravity.

[0109] In some embodiments of the present invention, a plurality of fastening grooves may be arranged along the width direction or length direction of the lower part of the head (100). A plurality of fastening grooves may be arranged parallel to each other along the left-right width direction of the lower part of the head (100). A plurality of fastening grooves may be arranged in a straight line or a curved shape along the front-rear length direction of the lower part of the head (100). A plurality of fastening grooves may be arranged in a curved shape to match the curvature of the lower part of the head (100).

[0110] According to some embodiments, a plurality of fastening grooves can extend the position adjustment range of the weight adjustment plate (105). A plurality of fastening grooves allows the weight adjustment plate (105) to be fixed in various positions, such as the front, center, and rear. A plurality of fastening grooves allows the user to finely adjust the center of gravity according to the swing style. A plurality of fastening grooves can facilitate the attachment and replacement of the weight adjustment plate (105).

[0111] According to some embodiments, the lower weight adjustment plate (105) may be designed to change its position in the forward and backward directions. The lower weight adjustment plate (105) may be selectively fixed at multiple positions, such as the front, center, and rear of the lower part of the head (100). Changing the forward and backward position of the lower weight adjustment plate (105) can be achieved by changing the insertion position of the fastener (104). The forward and backward movement distance of the lower weight adjustment plate (105) may be determined by the spacing of the fastener arrangement and the length of the lower part of the head (100).

[0112] In some embodiments of the present invention, the front-to-rear position variable design allows the user to adjust the center of gravity forward or backward. The user can move the center of gravity forward by fixing the lower weight adjustment plate (105) to the front. The user can move the center of gravity backward by fixing the lower weight adjustment plate (105) to the rear. The front-to-rear position variable design can be customized according to the user's swing style, force distribution, direction of impact, etc.

[0113] In some embodiments of the present invention, a front-rear position variable design can be implemented by the arrangement of fastening grooves and the selective insertion of fasteners (104). The arrangement of fastening grooves of the lower weight adjustment plate (105) is arranged continuously in the front-rear direction. The user can fix the position of the weight adjustment plate (105) by inserting a fastener (104) into a fastening groove at a desired position. The selective insertion of the fastener (104) allows for a rapid change in the position of the weight adjustment plate (105).

[0114] In some embodiments of the present invention, the lower weight adjustment plate (105) may be designed to maintain fastening rigidity even with repeated fastening and unfastening. The fastening member (104) insertion portion of the lower weight adjustment plate (105) may be reinforced with a metal insert or a reinforcing material. The fastening member (104) of the lower weight adjustment plate (105) may be treated to prevent thread wear. The fastening member (104) of the lower weight adjustment plate (105) is designed so that the fastening force does not decrease even with repeated assembly and unfastening.

[0115] According to some embodiments, the fastener (104) may be applied in a structure that prevents loosening due to vibration and impact. The fastener (104) may include a loosening prevention structure such as a lock nut, a spring washer, or a double thread. The fastener (104) can be verified to prevent loosening through a vibration test after fastening. The fastener (104) can maintain a fastened state even under impact loads generated during striking.

[0116] According to some embodiments, metal inserts, washers, lock nuts, etc. may be used to preserve fastening rigidity. A metal insert may be inserted into the fastening member (104) insertion part of the lower weight adjustment plate (105) to increase fastening rigidity. A flat washer, a spring washer, etc. may be inserted between the fastening member (104) and the lower weight adjustment plate (105) to distribute the fastening force. A lock nut prevents the fastening member (104) from loosening, thereby maintaining fastening rigidity even during repeated use.

[0117] According to some embodiments, the lower weight adjustment plate (105) can perform the function of adjusting the center of gravity of the head (100). The lower weight adjustment plate (105) can be attached to a designated location on the lower part of the head (100) to change the overall weight distribution. Changing the position of the lower weight adjustment plate (105) can move the center of gravity of the head (100) forward or backward. The weight and position of the lower weight adjustment plate (105) are designed to quantitatively control the amount of center of gravity shift.

[0118] According to some embodiments, the center of gravity of the head (100) can be moved forward or backward depending on the position change of the lower weight adjustment plate (105). When the lower weight adjustment plate (105) is fixed at the front, the center of gravity moves to the front of the head (100). When the lower weight adjustment plate (105) is fixed at the rear, the center of gravity moves to the rear of the head (100). The position change of the lower weight adjustment plate (105) can be finely adjusted in units of 5 mm, 10 mm, etc.

[0119] In some embodiments of the present invention, the center of gravity adjustment principle can affect the rotational characteristics of the head (100) and the stability of the ball's direction during a swing. If the center of gravity is located forward, the rotational response of the head (100) during a swing may be faster. If the center of gravity is located backward, the stability of the head (100) during a ball strike may be increased. The center of gravity adjustment can be customized according to the user's swing style, force distribution, ball striking distance, etc.

[0120] According to some embodiments, the position adjustment of the lower weight adjustment plate (105) can be utilized to optimize swing balance. By adjusting the position of the lower weight adjustment plate (105), the rotational inertia and swing trajectory of the head (100) can be controlled. Adjusting the position of the lower weight adjustment plate (105) can minimize shaking of the head (100) during a swing. Adjusting the position of the lower weight adjustment plate (105) can increase energy transfer efficiency during a shot.

[0121] In some embodiments of the present invention, swing balance optimization can be achieved by adjusting the center of gravity to match the user's swing style and force distribution. The user can select the position of the lower weight adjustment plate (105) according to their swing style. A user whose force is concentrated at the front can balance by moving the center of gravity to the rear. A user whose force is concentrated at the rear can adjust the swing balance by moving the center of gravity to the front.

[0122] In some embodiments of the present invention, swing balance optimization can provide the effect of minimizing shaking of the head (100) during impact. Adjusting the position of the lower weight adjustment plate (105) can suppress left-right shaking of the head (100) during impact. Adjusting the position of the lower weight adjustment plate (105) can increase consistency in the direction of impact. Adjusting the position of the lower weight adjustment plate (105) can improve the stability of the head (100) in the latter part of the swing.

[0123] In some embodiments of the present invention, the lower weight adjustment plate (105) may be designed to allow for custom settings for each user. The arrangement of fastening grooves and position adjustment functions of the lower weight adjustment plate (105) can respond to various user needs. The lower weight adjustment plate (105) can be customized according to user characteristics such as age, gender, body type, and swing habits. The lower weight adjustment plate (105) may be implemented as a replaceable or variable structure according to the user's preference.

[0124] According to some embodiments, the user can select the position of the weight adjustment plate (105) according to their body type, swing habits, and preferred feel of hitting the ball. The user can fix the weight adjustment plate (105) in a desired position, such as the front, center, or rear. The user can find the optimal center of gravity position through repeated testing. The user can customize the feel of hitting the ball, swing balance, distance control, etc., by changing the position of the weight adjustment plate (105).

[0125] According to some embodiments, the custom setting function can accommodate users of various age groups and physical strength levels. The custom setting function of the lower weight adjustment plate (105) can be applied to suit the physical conditions of various users, such as children, women, and the elderly. The custom setting function of the lower weight adjustment plate (105) allows users with weak physical strength to adjust their center of gravity to reduce swing fatigue. The custom setting function of the lower weight adjustment plate (105) can be widely utilized by everyone from professional players to beginners.

[0126] In some embodiments of the present invention, the lower weight adjustment plate (105) may be designed to maintain durability even with repeated position adjustment and fastening. The fastening member (104) insertion portion of the lower weight adjustment plate (105) may be made of wear-resistant metal or reinforced plastic. The fastening member (104) of the lower weight adjustment plate (105) is designed so that no deformation occurs even with repeated assembly and disassembly. The fastening member (104) of the lower weight adjustment plate (105) may be verified for performance degradation upon repeated use through a durability test.

[0127] In some embodiments of the present invention, the fastener (104) and the fastening groove may be made of a material resistant to wear and deformation. The fastener (104) may be made of a wear-resistant metal such as stainless steel or hardened steel. The fastening groove may be reinforced with glass fiber reinforced plastic, metal inserts, etc. The selection of the material for the fastener (104) and the fastening groove is determined with an emphasis on maintaining durability for repeated use and fastening rigidity.

[0128] In some embodiments of the present invention, the repeatable adjustment durability can ensure the reliability of the center of gravity adjustment function even during long-term use. The repeatable adjustment durability of the lower weight adjustment plate (105) can be verified through more than 1,000 fastening and unfastening tests. The repeatable adjustment durability of the lower weight adjustment plate (105) can maintain fastening rigidity and position fixing force even after long-term use. The repeatable adjustment durability of the lower weight adjustment plate (105) can provide the user with a continuous center of gravity adjustment function.

[0129] According to some embodiments, a bulkhead structure for weight distribution may be formed inside the head (100). The internal bulkhead structure of the head (100) can distribute the load of the lower weight adjustment plate (105) to the entire head (100). The internal bulkhead structure of the head (100) can increase durability by distributing the impact generated during striking through multiple paths. The internal bulkhead structure of the head (100) may be formed integrally in an injection molding or extrusion molding process.

[0130] In some embodiments of the present invention, an internal rib or bulkhead may be connected to a lower weight adjustment plate (105) to assist in weight distribution and structural rigidity. The internal rib may be positioned around the fastening location of the lower weight adjustment plate (105) to distribute the load. The internal bulkhead may connect the lower and side of the head (100) to increase structural rigidity. The internal rib or bulkhead may effectively distribute the load of the fastening member (104) of the lower weight adjustment plate (105).

[0131] According to some embodiments, the internal ribs and bulkheads may be formed integrally during the molding process of the head (100) or assembled as separate parts. The internal ribs and bulkheads may be formed directly within the mold during injection molding. The internal ribs and bulkheads may be manufactured as separate plastic or metal parts and inserted during the assembly stage. The internal ribs and bulkheads may be implemented in various shapes and arrangements according to the structural requirements of the head (100).

[0132] In some embodiments of the present invention, the internal ribs and bulkheads may be designed to effectively distribute the load of the lower weight adjustment plate (105). The internal ribs and bulkheads can distribute the load generated at the fastening location of the lower weight adjustment plate (105) to the entire head (100). The internal ribs and bulkheads can relieve stress concentrated in specific areas by securing multiple load distribution paths. The internal ribs and bulkheads can prevent the load of the fastening member (104) of the lower weight adjustment plate (105) from being directly transmitted to the surface of the head (100).

[0133] In some embodiments of the present invention, the weight distribution optimization design can contribute to improving the vibration characteristics and durability of the entire head (100). The internal ribs and bulkheads can increase the durability of the head (100) by absorbing and dispersing vibrations generated during striking. The internal ribs and bulkheads can prevent structural deformation even under repeated impacts. The internal ribs and bulkheads can influence the feel of the ball and noise characteristics by controlling the vibration characteristics of the head (100).

[0134] In some embodiments of the present invention, the weight distribution structure can prevent the impact from being concentrated on a specific area when hitting the ball. The internal ribs and partitions can be designed so that the impact from hitting the ball is distributed to various parts, such as the bottom, sides, and front of the head (100). The internal ribs and partitions can prevent the impact load from being concentrated on the fastener (104) or the lower weight adjustment plate (105). The internal ribs and partitions can contribute to improving the overall lifespan and durability of the head (100).

[0135] In some embodiments of the present invention, the internal ribs and bulkheads may serve to secure the structural rigidity of the head (100). The internal ribs and bulkheads may suppress deformation of the head (100) and increase resistance to loads of the fastener (104). The internal ribs and bulkheads may improve the overall rigidity and durability of the head (100). The internal ribs and bulkheads may prevent structural deformation from occurring even under repeated impacts.

[0136] In some embodiments of the present invention, the thickness, height, and spacing of the ribs may be optimized to ensure structural rigidity. The thickness of the inner ribs may be determined according to the results of structural analysis, such as 2 mm or 3 mm. The height and spacing of the inner ribs may be designed to distribute load and ensure rigidity. The shape of the inner ribs and bulkheads may be optimized by considering the total weight and balance of the head (100).

[0137] In some embodiments of the present invention, structural rigidity can increase resistance to repeated impacts and loads on the fastener (104). The internal ribs and bulkheads are designed to withstand the maximum impact load generated during impact. The internal ribs and bulkheads can prevent structural damage from occurring even when the load on the fastener (104) is applied repeatedly. The internal ribs and bulkheads can maintain structural rigidity even during long-term use of the head (100).

[0138] In some embodiments of the present invention, internal ribs and bulkheads may be applied to the lower part, side part, or around the weight adjustment plate (105) fastening part of the head (100). The internal ribs and bulkheads may be arranged radially or in a grid pattern centered on the fastening position of the lower weight adjustment plate (105). The internal ribs and bulkheads may increase structural rigidity by connecting the side part and the lower part of the head (100). The internal ribs and bulkheads may be concentrated around the weight adjustment plate (105) fastening part to enhance load distribution.

[0139] In some embodiments of the present invention, during the manufacturing process, internal ribs and bulkheads may be formed during injection molding, extrusion molding, or an assembly step. Internal ribs and bulkheads may be formed directly within the mold during the injection molding process. Internal ribs and bulkheads may be inserted during a separate assembly step after extrusion molding. Internal ribs and bulkheads may be applied in various processes depending on the structural requirements of the head (100).

[0140] In some embodiments of the present invention, the application location may be designed in conjunction with the fastening location of the lower weight adjustment plate (105). The arrangement of the internal ribs and bulkheads may be designed to coincide with the fastening location of the lower weight adjustment plate (105). The application location of the internal ribs and bulkheads may be optimized to ensure load distribution and fastening rigidity of the weight adjustment plate (105). The application location of the internal ribs and bulkheads may be determined by considering the overall structure and balance of the head (100).

[0141] In some embodiments of the present invention, the feel and noise control may aim to provide a pleasant hitting experience to the user by controlling the impact sound and vibration characteristics generated when using the park golf club head (100). The feel and noise control may attenuate the impact sound generated when the head (100) hits the ball or control noise in a specific frequency band. The feel and noise control may reduce the magnitude and duration of vibration transmitted to the hand by changing the vibration transmission path of the head (100). The feel and noise control may be implemented by combining various design elements such as the material, internal structure, reinforcing plate, and porous structure of the head (100). For example, placing a porous structure inside the head (100) can reduce noise by dispersing the energy of the impact sound. Attaching a reinforcing plate to the front of the head (100) can adjust the timbre of the hitting sound along with the rebound force. The feel and noise control may be designed to maintain consistent hitting characteristics even with repeated use.

[0142] In some embodiments of the present invention, the feel of the ball and noise control can be implemented by integrally designing the internal structure, material, and acoustic characteristic control pattern of the head (100). The feel of the ball and noise control can be implemented by combining multiple components such as partitions, ribs, porous structures, reinforcing plates, and weight control plates (105) inside the head (100). The feel of the ball and noise control can improve shock absorption and vibration damping characteristics by utilizing the composite properties of coffee grounds powder and synthetic resin. The feel of the ball and noise control can finely adjust the amplitude, duration, and frequency distribution of the ball striking sound by applying an acoustic characteristic control pattern. For example, if ribs are placed inside the head (100), the vibration transmission path is dispersed, and noise can be reduced. If grooves or patterns are formed on the surface of the head (100), noise in a specific frequency band can be selectively dampened.

[0143] According to some embodiments, the head (100) may be a park golf club (1) with acoustic properties controlled to reduce impact sound when hitting. The head (100) may reduce the magnitude of impact sound by more than 10 dB by applying an internal space design and an acoustic property control pattern. The head (100) may absorb high-frequency noise generated when hitting through a combination of a porous structure and a reinforcing plate. The head (100) may mitigate the impact transmitted to the hand by utilizing the vibration damping properties of a coffee grounds composite. The head (100) may be designed with a durable structure so that acoustic properties do not change even with repeated hitting. The head (100) may implement various hitting sound effects by adjusting the position and shape of the acoustic property control pattern. The head (100) may apply replaceable reinforcing plates or internal structural modifications to allow the tone of the hitting sound to be adjusted according to the user's preference. The head (100) may be a park golf club (1) with acoustic properties controlled to reduce impact sound when hitting.

[0144] In some embodiments of the present invention, the internal space design can control the volume, bulkhead structure, porous arrangement, etc., of the inside of the head (100) to control the volume and timbre of the sound generated upon striking. The internal space design can adjust the resonance frequency by setting the volume inside the head (100) to a range of 100 to 200 cm³. The internal space design can disperse the reflection path of impact sound by applying a bulkhead structure. The internal space design can increase the sound absorption rate by uniformly arranging a porous structure inside the head (100). The internal space design can emphasize or attenuate a specific timbre by adjusting the curved shape inside the head (100). For example, if bulkheads with different curvatures are placed inside, the resonance characteristics of the striking sound may change. The internal space design can finely control the volume and timbre of the striking sound by adjusting the volume of the head (100) and the position of the bulkheads.

[0145] According to some embodiments, the internal space design can ensure consistency in the feel of the ball by optimizing the impact transmission path and vibration damping characteristics. The internal space design can design the impact transmission path in a straight or curved shape so that vibrations dissipate quickly. The internal space design can reduce vibrations transmitted to the hand by more than 30% by placing a porous structure with excellent vibration damping characteristics inside the head (100). The internal space design can selectively dampen the frequency band of vibrations generated during striking by adjusting the thickness and position of the partitions. The internal space design can be implemented as a durable structure so that vibration damping characteristics are maintained even with repeated striking. The internal space design can ensure consistency in the feel of the ball by combining the impact transmission path and vibration damping characteristics.

[0146] In some embodiments of the present invention, the internal space design can be combined with an acoustic characteristic control pattern to improve the overall noise control performance of the head (100). The internal space design can selectively attenuate noise in a specific frequency band by combining with the acoustic characteristic control pattern. The internal space design can maximize noise control performance by applying an acoustic characteristic control pattern, such as ribs, grooves, or porous structures, inside the head (100). The internal space design can implement various noise control effects by adjusting the position and shape of the acoustic characteristic control pattern. For example, by combining the internal space design with the acoustic characteristic control pattern, the volume, timbre, and duration of the hitting sound can be finely controlled. The internal space design can improve the overall noise control performance of the head (100) by combining with the acoustic characteristic control pattern.

[0147] According to some embodiments, the acoustic characteristic control pattern may include grooves, ribs, porous structures, and the arrangement of reinforcing plates formed inside or on the surface of the head (100). The acoustic characteristic control pattern may attenuate noise of a specific frequency by forming a groove with a depth of 1 to 3 mm and a width of 2 to 5 mm inside the head (100). The acoustic characteristic control pattern may disperse the vibration transmission path by arranging 2 to 4 ribs inside the head (100). The acoustic characteristic control pattern may increase the sound absorption rate by applying a porous structure to the surface or inside of the head (100). The acoustic characteristic control pattern may adjust the timbre and amplitude of the hitting sound by attaching a reinforcing plate to the front of the head (100). For example, by changing the thickness and material of the reinforcing plate, high or low frequency components of the hitting sound can be selectively emphasized. The acoustic characteristic control pattern may be implemented by combining the arrangement and shape of grooves, ribs, porous structures, and reinforcing plates according to various embodiments.

[0148] According to some embodiments, the acoustic characteristic control pattern can be designed to selectively attenuate or amplify noise in a specific frequency band generated during striking. The acoustic characteristic control pattern can adjust the pore size and density of the porous structure to attenuate noise in the 1–3 kHz band. The acoustic characteristic control pattern can amplify low-frequency striking sounds by applying a reinforcing plate with a thickness of 5–8 mm. The acoustic characteristic control pattern can control the resonance effect in a specific frequency band by adjusting the depth and spacing of the grooves. The acoustic characteristic control pattern can be custom-designed to determine the frequency band to be attenuated or amplified according to user preference. The acoustic characteristic control pattern can be implemented with a durable structure to maintain noise control characteristics even with repeated striking.

[0149] In some embodiments of the present invention, the acoustic characteristic control pattern can be combined with the material, thickness, and internal structure of the head (100) according to various embodiments to adjust the quality of the striking sound. The acoustic characteristic control pattern can be combined with the material characteristics of the coffee grounds composite to maximize the attenuation effect of impact sound. The acoustic characteristic control pattern can finely control the volume and timbre of the striking sound by adjusting the thickness of the head (100) to a range of 10 to 20 mm. The acoustic characteristic control pattern can be combined with the internal structure to adjust the duration and resonance characteristics of the striking sound. For example, combining a thick reinforcing plate with a porous structure can attenuate low-frequency noise and emphasize high-frequency striking sounds. The acoustic characteristic control pattern can be combined with the material, thickness, and internal structure according to various embodiments to adjust the quality of the striking sound.

[0150] According to some embodiments, the improvement in user perception quality can be achieved by comprehensively improving vibrations, noise, and rebound sensations transmitted to the hand during hitting. The improvement in user perception quality can reduce vibrations transmitted to the hand by more than 30% by applying a vibration damping structure to the head (100). The improvement in user perception quality can adjust the volume and tone of the hitting sound to suit the user's preference by applying a noise control pattern. The improvement in user perception quality can mitigate the impact felt in the hand during hitting by adjusting the rebound force. For example, by combining a porous structure and a reinforcing plate, vibrations and noise can be reduced simultaneously. The improvement in user perception quality can be achieved through a durable structure that maintains consistent hitting sensation and noise characteristics even during repeated use.

[0151] According to some embodiments, user tactile quality enhancement can provide a hitting sensation that meets various user needs through the optimization of internal space design and acoustic characteristic control patterns. User tactile quality enhancement can realize various hitting sensations by adjusting the volume, bulkhead structure, porous arrangement, etc., of the internal space design. User tactile quality enhancement can provide hitting sound effects that suit user preferences by changing the location and shape of the acoustic characteristic control patterns. User tactile quality enhancement can realize customized hitting sensations and noise characteristics by combining internal space design and acoustic characteristic control patterns. For example, increasing the internal space volume and adding ribs can provide a soft hitting sensation. User tactile quality enhancement can be designed to provide a hitting sensation that meets various user needs.

[0152] According to some embodiments, the user-perceived quality improvement can be designed to maintain consistent hitting feel and noise characteristics even during repeated use. The user-perceived quality improvement can be designed so that the hitting feel and noise characteristics do not change even with repeated hitting by applying durable materials and structures. The user-perceived quality improvement can maintain quality even during long-term use by applying durable components such as a reinforcing plate, a weight adjustment plate (105), and a porous structure. The user-perceived quality improvement can verify consistency in a repeated use environment through quality inspection and durability testing. The user-perceived quality improvement can be designed to maintain consistent hitting feel and noise characteristics even during repeated use.

[0153] FIG. 3 illustrates a park golf club head (100) according to one embodiment.

[0154] In some embodiments of the present invention, the head (100) may be molded from a composite material comprising coffee grounds powder and synthetic resin. The head (100) may be integrally molded by mixing the coffee grounds powder and synthetic resin. The head (100) may select a mixing ratio of coffee grounds powder and synthetic resin from 10:90 to 40:60. The head (100) may be molded by stirring and mixing the coffee grounds powder and synthetic resin, and then injecting the mixture into a metal outer mold and a silicone mold. The head (100) may take on a final shape after undergoing curing and demolding processes following molding. The head (100) may improve tensile strength and durability by adding natural fiber reinforcement in addition to the coffee grounds powder and synthetic resin. The head (100) may use vacuum injection or a vibrating table to minimize the generation of air bubbles during composite molding. After molding, the head (100) may undergo planar machining, corner rounding, and dimensional precision correction through CNC machining.

[0155] In some embodiments of the present invention, the head (100) can simultaneously secure durability, shock absorption, repulsion, environmental suitability, and recyclability by controlling various detailed physical properties such as the particle size, surface treatment, internal porous structure, and application of additives of the coffee grounds powder. The head (100) can control molding flowability and surface texture by controlling the particle size distribution of the coffee grounds powder. The head (100) can increase adhesion to synthetic resin by degreasing or carbonizing the surface of the coffee grounds powder. The head (100) can disperse impact energy and increase repulsion by forming a porous structure inside. The head (100) can enhance hygiene and durability by applying functional additives such as antibacterial, deodorizing, and weather-resistant agents. The head (100) can be designed with a structure that allows for re-molding after grinding to facilitate recycling. For environmental suitability, the head (100) can set the content of the coffee grounds powder to 20% by weight or more.

[0156] According to some embodiments, the head (100) may have an average particle diameter of coffee grounds powder in the range of 50 to 500 micrometers and may be homogenized so that the relative standard deviation of the particle size distribution is 10% or less. The head (100) may grind the coffee grounds powder with a fine grinding device to adjust the average particle diameter to 50 to 500 micrometers. The head (100) may manage the relative standard deviation of the particle size distribution to 10% or less by applying sieve specifications. The head (100) may maintain a constant viscosity of the mixture during molding through particle size homogenization. The head (100) may ensure surface smoothness and uniformity of internal pores by controlling particle size and distribution.

[0157] According to some embodiments, the head (100) may have improved adhesion to synthetic resin and moisture resistance by degreasing or carbonizing the coffee grounds powder. The head (100) may perform degreasing treatment by hot-air drying the coffee grounds powder at 100 to 120°C. The head (100) may reduce the moisture content to 5% or less by carbonizing the coffee grounds powder at 300°C or higher. By using degreasing or carbonized coffee grounds powder, the head (100) may improve interfacial adhesion to synthetic resin by 20% or more. The head (100) may additionally apply silane treatment or weather-resistant additives to improve moisture resistance.

[0158] In some embodiments of the present invention, the head (100) may have a porous structure formed inside to enable shock dispersion, increased rebound force, lightweighting, and control of acoustic properties. The head (100) may form a porous region with a fine cell structure inside by adding a foaming agent or a pore-forming agent during the molding process. The head (100) may secure a path for absorbing impact energy by setting the pore size of the porous structure to a range of 0.1 to 1.0 mm. The head (100) may simultaneously achieve lightweighting and increased rebound force by adjusting the porosity of the porous structure to a range of 10 to 40%. The head (100) may maintain fatigue durability even under repeated impacts by uniformly distributing the porous structure. The head (100) may finely control acoustic properties during striking through a combination of the porous structure, a reinforcing plate, and a weight adjustment plate (105).

[0159] In some embodiments of the present invention, the head (100) can improve hygiene and durability by applying functional additives such as antibacterial, deodorizing, and weather resistance. The head (100) may add silver nanoparticles, copper powder, natural antibacterial agents, etc. for antibacterial function. The head (100) may add activated carbon powder or zeolite for deodorizing function. The head (100) may apply silane treatment agents, UV blockers, and moisture-resistant fillers to improve weather resistance. The head (100) can enhance hygiene and durability without deteriorating physical properties by adjusting the content of functional additives to a range of 0.5 to 5 weight percent.

[0160] According to some embodiments, the head (100) may have a recyclable structure that can be crushed after use and fed into a remolding process. The head (100) may be crushed by a crushing device after use to form pieces with an average particle size of 1 to 5 mm. The head (100) may remix the crushed pieces with synthetic resin and feed them into a remolding process. The head (100) can maintain mechanical strength and durability of 80% or more even during repeated remolding. The head (100) can be designed to minimize waste generation through its recyclable structure and be suitable for a resource circulation process.

[0161] According to some embodiments, the coffee grounds powder specifications can have a direct effect on the molding characteristics, durability, functionality, and environmental suitability of the park golf club head (100). The mechanical strength and moisture resistance of the park golf club head (100) may vary depending on the coffee grounds powder specifications, particle size, particle size distribution, surface treatment method, and whether additives are applied. The coffee grounds powder specifications may affect the viscosity of the mixture and mold injection efficiency during the molding process. The coffee grounds powder specifications may determine the feasibility of implementing additional functions such as antibacterial, deodorizing, and eco-friendliness. The coffee grounds powder specifications may enhance environmental suitability based on the utilization of recycled resources and biodegradable characteristics.

[0162] According to some embodiments, coffee grounds powder can optimize the performance of composites by controlling various detailed physical properties, such as particle size, distribution, surface treatment, and the application of functional additives. Coffee grounds powder can improve molding flowability and surface quality by controlling particle size and distribution. Coffee grounds powder can increase interfacial adhesion with synthetic resins by degreasing or carbonizing the surface. Coffee grounds powder can enhance the hygiene and durability of composites by adding functional additives, such as antimicrobial agents, deodorizers, and weather-resistant additives. Coffee grounds powder can improve tensile strength and durability by mixing with fine glass fibers or natural fiber reinforcements.

[0163] In some embodiments of the present invention, the particle size and distribution of the coffee grounds powder can affect molding flowability and the surface quality of the final product. The particle size of the coffee grounds powder can directly affect the viscosity of the mixture and the filling rate within the mold. If the particle size distribution of the coffee grounds powder is uniform, bubble formation during molding is suppressed and a smooth surface can be formed. The particle size and distribution of the coffee grounds powder can contribute to maintaining consistent flowability in extrusion or injection molding processes.

[0164] In some embodiments of the present invention, the average particle diameter of the coffee grounds powder can be adjusted to a range of 50 to 500 micrometers. The average particle diameter of the coffee grounds powder can be adjusted to 50 to 500 micrometers using fine grinding equipment. Only particles in the range of 50 to 500 micrometers can be selected from the coffee grounds powder by applying sieve specifications. When the average particle diameter of the coffee grounds powder is 50 to 500 micrometers, the viscosity of the molding mixture can be maintained constant. When the average particle diameter of the coffee grounds powder is 50 to 500 micrometers, the surface of the final product can be formed uniformly.

[0165] According to some embodiments, the particle size distribution of the coffee grounds powder can be uniformized with a relative standard deviation of 10% or less. The coffee grounds powder can secure a uniform particle size distribution with a relative standard deviation of 10% or less through a sieving process. When the particle size distribution of the coffee grounds powder is maintained at a relative standard deviation of 10% or less, the flowability and filling rate of the mixture during molding can be maintained consistently. When the particle size distribution of the coffee grounds powder is uniform, the generation of bubbles can be suppressed during the mold injection and extrusion molding processes.

[0166] According to some embodiments, the viscosity of the mixture can be maintained constant during molding by controlling the particle size and distribution of the coffee grounds powder. When the particle size of the coffee grounds powder is adjusted to a range of 50 to 500 micrometers, the viscosity can be maintained constant when mixed with synthetic resin. When the particle size distribution of the coffee grounds powder is homogenized to a relative standard deviation of 10% or less, the flowability of the mixture can be improved. By controlling the particle size and distribution of the coffee grounds powder, the filling rate within the mold can be increased and the molding defect rate can be reduced.

[0167] According to some embodiments, the uniformity of the particle size of the coffee grounds powder can contribute to ensuring flowability during the mold injection and extrusion molding processes. The uniformity of the particle size of the coffee grounds powder can suppress the generation of bubbles in the mixture when using vacuum injection or a vibrating table. The uniformity of the particle size of the coffee grounds powder can facilitate continuous strand formation during extrusion molding. The uniformity of the particle size of the coffee grounds powder allows the mixture to be evenly distributed within the mold, thereby increasing the dimensional accuracy of the final product.

[0168] According to some embodiments, surface treatment of coffee grounds powder can play an important role in improving interfacial adhesion with synthetic resin and moisture resistance. Oil and moisture can be removed from the surface of the coffee grounds powder through hot air drying or a degreasing process. Micropores can be formed on the surface of the coffee grounds powder through a carbonization process at 300°C or higher, thereby improving interfacial adhesion with synthetic resin. Moisture resistance can be enhanced on the surface of the coffee grounds powder through silane treatment or the application of weather-resistant additives.

[0169] In some embodiments of the present invention, the coffee grounds powder may be degreased by hot-air drying at 100 to 120°C. The coffee grounds powder may be degreased by hot-air drying in a dryer at 100 to 120°C for 1 to 2 hours to remove oil and moisture. The coffee grounds powder may be dried naturally for 3 to 5 days to assist in the degreaser treatment. Degreaser treatment of the coffee grounds powder can increase interfacial bonding strength when mixed with synthetic resin.

[0170] According to some embodiments, the coffee grounds powder can be carbonized at 300°C or higher to reduce its moisture content to 5% or less. The coffee grounds powder can be carbonized by heating it in an electric furnace or a hot air furnace at 300 to 350°C for at least one hour. The carbonization treatment of the coffee grounds powder can form fine pores to improve interfacial adhesion with synthetic resins. The carbonization treatment of the coffee grounds powder can reduce its moisture content to 5% or less, thereby increasing the moisture resistance of the product after molding.

[0171] In some embodiments of the present invention, coffee grounds powder may undergo degreasing or carbonization treatment to improve adhesion to synthetic resin and moisture resistance. After degreasing treatment, surface oil is removed from the coffee grounds powder, which can increase interfacial bonding strength with synthetic resin by more than 20%. After carbonization treatment, fine pores are formed in the coffee grounds powder, which can facilitate penetration of synthetic resin. Moisture resistance of the coffee grounds powder may be further improved through silane treatment or the application of weather-resistant additives.

[0172] According to some embodiments, coffee grounds powder can be imparted with various additional functions such as antibacterial, deodorizing, and eco-friendliness. For antibacterial functions, silver nanoparticles, copper powder, natural antibacterial agents, etc., may be added to the coffee grounds powder. For deodorizing functions, activated carbon powder or zeolite may be added to the coffee grounds powder. Coffee grounds powder can ensure eco-friendliness through the utilization of renewable resources and biodegradable properties.

[0173] According to some embodiments, the coffee grounds powder may contain a component that provides an antibacterial function. The coffee grounds powder may inhibit bacterial growth by adding silver nanoparticles or natural antibacterial agents. The coffee grounds powder may enhance hygiene by adjusting the content of the antibacterial additive to 0.5 to 2 weight percent. The coffee grounds powder may be stirred and mixed so that the antibacterial component is uniformly distributed within the composite material.

[0174] According to some embodiments, the coffee grounds powder may contain a component that provides a deodorizing function. The coffee grounds powder may adsorb odor components by adding activated carbon powder or zeolite. The coffee grounds powder may maximize the deodorizing effect by adjusting the content of the deodorizing additive to 1 to 5 weight percent. The coffee grounds powder may be mixed so that the deodorizing component is uniformly distributed throughout the composite material.

[0175] In some embodiments of the present invention, coffee grounds powder can ensure eco-friendliness through the utilization of renewable resources and biodegradable properties. Coffee grounds powder can contribute to resource circulation by recycling by-products of the coffee industry. Coffee grounds powder can be designed to be mixed with biodegradable synthetic resin so that it can be ground and remolded after use. Coffee grounds powder can minimize the use of harmful additives for environmental suitability.

[0176] In some embodiments of the present invention, the internal porous structure can contribute to shock absorption, repulsion, weight reduction, and improved durability of the park golf club head (100). The internal porous structure can be implemented as a composite structure in which a plurality of pores are formed inside the head (100). The internal porous structure can absorb external shocks by dispersing energy within the pores when an impact is applied. The internal porous structure can increase repulsion through the elastic deformation and recovery characteristics of the pores. The internal porous structure can reduce the overall weight by optimizing the shape and distribution of the pores. The internal porous structure can improve durability by suppressing the propagation of microcracks caused by repeated impacts.

[0177] In some embodiments of the present invention, the internal porous structure can exhibit various physical properties depending on the shape, density, distribution of the pores, and the application of additives. The pore shape of the internal porous structure can be designed to be spherical, elliptical, irregular, etc. The pore density of the internal porous structure can be defined as the number of pores per unit volume. The pore distribution of the internal porous structure can be implemented as a uniform or non-uniform distribution. Various additives, such as silane treatment agents, weather-resistant fillers, and antimicrobial agents, can be applied to the internal porous structure. Depending on the type and content of the additives, the internal porous structure may possess additional physical properties such as moisture resistance, weather resistance, and antimicrobial properties.

[0178] According to some embodiments, an internal porous structure can be formed by mixing conditions of coffee grounds powder, synthetic resin, reinforcing material, and additives during a molding process. The size and distribution of pores in the internal porous structure may vary depending on the mixing ratio of coffee grounds powder and synthetic resin. Tensile strength and durability can be enhanced by adding natural fiber reinforcing material or fine glass fibers to the internal porous structure. The shape and density of pores in the internal porous structure can be controlled by adjusting molding process conditions, such as adding a foaming agent, vacuum injection, or using a vibrating table. Process parameters such as stirring speed, time, and temperature can be optimized for uniform mixing of additives in the internal porous structure.

[0179] In some embodiments of the present invention, the pore shape and density of the internal porous structure may affect the mechanical properties and impact dispersion performance of the park golf club head (100). The pore shape of the internal porous structure may be designed in various forms, such as spherical, elliptical, or polyhedral. The pore density of the internal porous structure may be quantified as the number of pores per unit volume. The pore shape of the internal porous structure may be determined by the particle size of the coffee grounds powder and the viscosity of the synthetic resin. The pore density of the internal porous structure may be controlled according to the amount of foaming agent added, molding pressure, and temperature conditions. The pore shape and density of the internal porous structure may have a direct effect on the energy dispersion path and repulsive force when an impact is applied.

[0180] In some embodiments of the present invention, the internal porous structure may be formed into a microcell structure with a size of tens to hundreds of micrometers. The microcells of the internal porous structure may be composed of an average diameter in the range of 50 to 500 micrometers. The microcells of the internal porous structure may be determined by the particle size of the coffee grounds powder and the sieving process. The microcells of the internal porous structure may be formed by controlling the size of bubbles in the foaming agent addition and vacuum injection processes.

[0181] According to some embodiments, the microcell structure can be controlled according to the particle size of the coffee grounds powder, the viscosity of the synthetic resin, and the mixing and foaming conditions. The pore size of the microcell structure may become smaller as the viscosity of the synthetic resin increases. The uniformity of the pores of the microcell structure may vary depending on the mixing and stirring speed and time. The number and size of the pores of the microcell structure can be controlled according to the type and amount of foaming agent added.

[0182] In some embodiments of the present invention, porosity may be defined as the ratio of pores to the total volume. Porosity may be calculated by dividing the total volume of pores in the internal porous structure by the total volume of the composite material. Porosity may have a direct effect on the weight reduction and shock absorption performance of the park golf club head (100).

[0183] According to some embodiments, the porosity can be controlled within a range of approximately 5% to 40%. When the porosity is 5% or less, the rigidity is increased, and when it is close to 40%, the weight reduction and shock absorption capacity may be increased. The porosity can be set to various values ​​such as 10%, 20%, and 30% depending on the purpose of use.

[0184] According to some embodiments, the porosity can be set according to the mixing ratio of the molding mixture, the amount of foaming agent added, and molding pressure and temperature conditions. The porosity can be set by adjusting the mixing ratio of coffee grounds powder and synthetic resin. The porosity can be increased by increasing the amount of foaming agent added. The porosity can be lowered by increasing the molding pressure, as this compresses the pores. The porosity can be controlled by adjusting the molding temperature to control the foaming reaction rate and pore formation.

[0185] According to some embodiments, a uniform distribution of pores may be important for ensuring the strength and durability of the park golf club head (100). A uniform distribution of pores can reduce the risk of breakage by preventing localized stress concentration. A uniform distribution of pores can suppress the occurrence of microcracks caused by repeated impacts.

[0186] According to some embodiments, a uniform distribution of pores can be achieved through process control, such as vacuum injection, the use of a vibrating table, and the optimization of mixing and stirring conditions. The vacuum injection process can suppress bubble generation and induce a uniform distribution of pores. The use of a vibrating table can remove bubbles within the mixture and make the size and location of the pores uniform. Optimizing the mixing and stirring speed and time can yield an internal porous structure with evenly distributed pores.

[0187] According to some embodiments, the internal porous structure can contribute to the dispersion of impact energy and the enhancement of rebound force. When an impact is applied, the internal porous structure can absorb external impact by dispersing energy within the pores through multiple paths. The internal porous structure can increase the rebound force upon impact due to the elastic deformation and recovery characteristics of the pores. The internal porous structure can optimize the effects of impact dispersion and rebound force enhancement by controlling the size, density, and distribution of the pores.

[0188] In some embodiments of the present invention, the pores of the internal porous structure can absorb external impact by dispersing energy through multiple paths upon impact. When an impact is applied, energy is dispersed along each pore of the internal porous structure, thereby preventing localized stress concentration. The pores of the internal porous structure are arranged in a multilayer structure so that impact energy can be gradually dissipated over several stages.

[0189] According to some embodiments, the microcell structure within the pores can reduce the risk of failure by gradually dissipating impact energy. The microcell structure can absorb energy through the elastic deformation of each cell when an impact is applied. The microcell structure can suppress the propagation of microcracks by dispersing energy at the interfaces between cells.

[0190] In some embodiments of the present invention, the internal porous structure can increase the repulsive force through the elastic deformation and recovery characteristics of the pores. The pores of the internal porous structure can convert stored energy into a repulsive force as they recover to their original shape after impact. The magnitude of the repulsive force may vary depending on the elastic modulus and recovery speed of the pores of the internal porous structure.

[0191] According to some embodiments, optimizing porosity and cell structure can minimize energy loss and increase rebound force upon impact. When porosity is set to an appropriate range, a portion of the impact energy can be stored and released as rebound force. Optimizing the arrangement and size of the cell structure can maximize the effect of increasing rebound force.

[0192] According to some embodiments, the internal porous structure can improve fatigue durability against repeated impacts. The internal porous structure can suppress structural damage even under repeated impacts by dispersing energy through the pores. The internal porous structure can increase durability during long-term use by delaying the occurrence and propagation of microcracks.

[0193] According to some embodiments, the uniform distribution of pores and the microcell structure can suppress the propagation of microcracks, thereby increasing durability during long-term use. The microcell structure with uniformly distributed pores can prevent stress concentration, thereby reducing fatigue failure. The microcell structure can improve durability by minimizing structural deformation caused by repeated impacts.

[0194] In some embodiments of the present invention, additives may be applied to suppress deformation of the internal porous structure due to changes in temperature and humidity. Weather-resistant additives may be mixed in to complement the characteristics of the coffee grounds composite material, which is sensitive to changes in temperature and humidity. The additives can suppress moisture adsorption within the pores and prevent structural deformation caused by expansion and contraction. The additives can contribute to maintaining the dimensional stability and durability of the park golf club head (100) during long-term use.

[0195] In some embodiments of the present invention, a silane treatment can be applied to the surface of coffee grounds powder and a composite material to suppress moisture adsorption and improve moisture resistance. The silane treatment can block moisture penetration by forming a silane bonding layer on the surface of the coffee grounds powder. The silane treatment can also be applied to the surface of the internal pores of the composite material to increase overall moisture resistance. The silane treatment can be applied to the coffee grounds powder in advance before molding, or applied to the surface of the composite material after molding as a coating.

[0196] According to some embodiments, a weather-resistant filler may be added to prevent expansion, shrinkage, and deformation due to changes in temperature and humidity. The weather-resistant filler may consist of inorganic fillers such as silica, alumina, and fine glass fibers. The weather-resistant filler may be uniformly mixed with coffee grounds powder and synthetic resin and dispersed within the composite material.

[0197] According to some embodiments, the weather-resistant filler is uniformly dispersed within the composite material to ensure long-term durability. When the weather-resistant filler is uniformly dispersed, structural deformation due to changes in temperature and humidity can be minimized. The weather-resistant filler can stably maintain the mechanical properties of the park golf club head (100) even under repeated environmental changes.

[0198] According to some embodiments, surface modification technology can inhibit the penetration of moisture and contaminants by changing the surface properties of coffee grounds powder and composite materials. Surface modification technology can impart hydrophilic or hydrophobic properties to the surface of coffee grounds powder by applying silane treatment, plasma treatment, nanocoating, etc. Surface modification technology can form a waterproof and UV-blocking coating layer on the surface after molding the composite material.

[0199] In some embodiments of the present invention, surface modification technology can be applied in various ways, such as silane treatment, plasma treatment, and nanocoating. Silane treatment can form a silane bonding layer on the surface of the coffee grounds powder and the composite material. Plasma treatment can increase the adhesion of the coating layer by changing the energy of the composite material surface. Nanocoating can inhibit the penetration of moisture and contaminants by forming an ultrathin protective layer on the surface of the composite material.

[0200] According to some embodiments, the park golf club head (100) may be designed with recycling and sustainability in mind. The composition ratio of coffee grounds powder and synthetic resin in the park golf club head (100) may be optimized to facilitate crushing and remolding after use. The bonding structure of the park golf club head (100) may be simplified to facilitate the separation and crushing of materials. The park golf club head (100) may include additives with enhanced heat resistance and moisture resistance to minimize degradation of physical properties even during repeated remolding processes. The park golf club head (100) may maintain tensile strength and durability during recycling by adding natural fiber reinforcement or fine glass fibers. The park golf club head (100) may be designed to enable hygienic recycling by including components that provide antibacterial or deodorizing functions. The park golf club head (100) may prevent deformation caused by changes in moisture and temperature during the recycling process through weather-resistant additives and silane treatment.

[0201] In some embodiments of the present invention, the park golf club head (100) may have a recyclable structure that can be crushed after use and fed into a remolding process. The park golf club head (100) may be implemented as a composite structure that can be processed into a powder or granular form by crushing the entire head (100). The park golf club head (100) may be fed directly into a remolding process even after crushing, as the main materials, such as coffee grounds powder, synthetic resin, and reinforcing material, are uniformly mixed. The park golf club head (100) may be designed to minimize the impact on the quality of the remolding even if the surface coating layer is separated during the recycling process or mixed during crushing. The durability and bonding strength of the material may be reinforced so that the park golf club head (100) can maintain mechanical strength and durability even after repeated crushing and remolding.

[0202] According to some embodiments, the park golf club head (100) may be reprocessed into a powder or granular form through a crushing process after use. The park golf club head (100) may be processed into granular particles of 1 to 5 mm in size or powder of 50 to 500 micrometers in size using a grinder or a crusher. The park golf club head (100) may include a sieving or magnetic separation process so that foreign substances and metal parts can be separated during crushing. After crushing, the park golf club head (100) may be stored in a granular or powder form and fed into a re-molding process.

[0203] According to some embodiments, the crushed park golf club head (100) may be fed into a remolding process together with synthetic resin and coffee grounds powder. The crushed park golf club head (100) may be mixed with new coffee grounds powder, synthetic resin, and natural fiber reinforcement to adjust the mixing ratio. After being uniformly mixed in a stirrer, the crushed park golf club head (100) may be fed into an extruder or mold injection process. During remolding, a viscosity modifier, a defoaming agent, a weather-resistant additive, etc., may be added to the crushed park golf club head (100).

[0204] In some embodiments of the present invention, the crushing and reshaping process can increase material circulation and resource efficiency of the park golf club head (100). The crushing and reshaping process can recycle the park golf club head (100) recovered after use as a raw material and use it for the production of new products. The crushing and reshaping process can reduce the amount of waste generated through the repeated use of the material. The crushing and reshaping process can reduce resource consumption and carbon emissions.

[0205] According to some embodiments, the park golf club head (100) may be designed with a material composition and bonding structure suitable for a recycling process. The mixing ratio of coffee grounds powder, synthetic resin, reinforcing material, and additives in the park golf club head (100) may be adjusted to be suitable for repeated remolding. The park golf club head (100) may be designed with a detachable fastening structure for metal parts, weight adjustment plates (105), reinforcing plates, etc. The park golf club head (100) may use an optional coating agent so that the surface coating layer can be easily removed during the recycling process or mixed during crushing.

[0206] In some embodiments of the present invention, the circulation process can enable the repeated reuse of key materials such as coffee grounds powder, synthetic resin, and reinforcing materials. The circulation process can produce a composite material of the same quality by mixing the crushed head (100) material with new coffee grounds powder and synthetic resin. The circulation process may include the repeated mixing and reuse of reinforcing materials such as natural fiber reinforcing materials and fine glass fibers. The circulation process can prevent the deterioration of physical properties by reintroducing functional additives such as antibacterial agents and weather-resistant additives.

[0207] In some embodiments of the present invention, the circular process design may link the manufacturing, use, recovery, crushing, and remolding steps of a park golf club head (100). The circular process design may include a series of process flows in which the park golf club head (100) is recovered after use, crushed and powdered, and then mixed with new raw materials to remold. The circular process design may ensure remolding quality by including quality inspection and foreign substance removal processes at each stage. The circular process design can maximize the resource recycling rate throughout the entire lifecycle of the park golf club head (100).

[0208] According to some embodiments, the park golf club head (100) can reduce environmental impact by utilizing biomass-based materials such as coffee grounds powder. The park golf club head (100) can increase the biomass ratio by setting the content of coffee grounds powder to 30 to 70 weight percent. In addition to coffee grounds powder, the park golf club head (100) may include natural fiber reinforcements such as hemp, flax, and bamboo fibers. The park golf club head (100) can reduce the proportion of fossil fuel-based materials by minimizing the use of synthetic resin.

[0209] According to some embodiments, the park golf club head (100) can reduce the amount of waste generated through a recycling process and a circular design. The park golf club head (100) can minimize the final amount of waste discharged by repeatedly crushing and reshaping it after use. The park golf club head (100) can prevent environmental pollution by separating by-products and foreign substances generated during the circular process. The park golf club head (100) can be equipped with dust collection and purification facilities for treating fine dust and wastewater generated during the recycling process.

[0210] According to some embodiments, the park golf club head (100) can reduce resource consumption and carbon emissions through the application of eco-friendly processes and materials. The park golf club head (100) can reduce the environmental burden associated with raw material extraction by utilizing renewable resources such as coffee grounds powder and natural fibers. The park golf club head (100) can apply manufacturing processes that consume less energy, such as low-temperature curing and vacuum injection. The park golf club head (100) can be designed to reduce its carbon footprint over its entire lifecycle.

[0211] In some embodiments of the present invention, the method for manufacturing a coffee grounds composite head (100) may include pretreatment of coffee grounds powder, mixing with synthetic resin, molding, curing, post-processing, attachment of parts, surface coating, quality inspection, and a recycling protocol. The method for manufacturing a coffee grounds composite head (100) may homogenize the particle size by recovering and drying the coffee grounds powder, followed by grinding and sieving. The coffee grounds powder may be uniformly mixed with synthetic resin and a binder using a stirrer. The mixed material may be injected into a mold using vacuum injection or a vibrating table. Curing may proceed within the mold under ambient temperature or thermal curing conditions. After curing is complete, the coffee grounds composite head (100) may be demolded from the silicone mold and undergo finishing processes such as planar machining and corner rounding using a CNC machine. The front reinforcing plate (102) and the lower weight adjustment plate (105) may be attached using epoxy adhesive and fasteners (104) after position alignment. An epoxy or lacquer coating layer may be formed on the surface by spraying or application. Finally, dimensional and strength verification, quality inspection, and recycling protocols may be applied.

[0212] According to some embodiments, the coffee grounds composite head (100) may use coffee grounds powder and synthetic resin as main raw materials and apply various reinforcing materials, additives, and functional coating layers. The coffee grounds composite head (100) may improve tensile strength and durability by adding natural fiber reinforcing materials (e.g., hemp, flax, bamboo fibers) or fine glass fibers. The coffee grounds composite head (100) may impart hygienic properties by adding components that provide antibacterial or deodorizing functions. The coffee grounds composite head (100) may increase stability against moisture and temperature changes by including weather-resistant additives, silane treatment agents, and surface modifiers. The coffee grounds composite head (100) may form a coating layer on its surface that has waterproof and UV-blocking functions.

[0213] According to some embodiments, the manufacturing process of the coffee grounds composite head (100) may consist of the steps of recovering coffee grounds, drying, grinding, sieving, uniform mixing with synthetic resin and binder, mold injection, curing, demolding, CNC finishing, attachment of the front reinforcing plate (102) and the lower weight control plate (105), waterproofing and UV protection coating, final quality inspection, and recycling. In the coffee grounds recovery step, coffee grounds generated from a cafe or coffee roasting plant can be collected on the same day. In the drying step, the moisture content can be managed through natural drying (3 to 5 days) or hot air drying (100 to 120°C). In the grinding and sieving step, the particle size can be adjusted to an average particle diameter of 50 to 500 micrometers and a relative standard deviation of 10% or less using fine grinding equipment and a sieve. In the mixing step with synthetic resin and binder, uniform mixing can be achieved by controlling viscosity and bubble generation in an agitator. In the mold injection stage, a metal outer mold and a silicone mold can be used to minimize air bubbles and manage the filling rate using a vacuum or vibrating table. In the curing stage, room temperature curing or thermal curing methods can be applied to control the time and temperature profiles. In the demolding stage, the silicone mold can be separated to prevent surface damage and perform an initial quality inspection. In the CNC finishing stage, flat machining, corner rounding, and dimensional precision correction can be performed. In the front reinforcement plate (102) and lower weight adjustment plate (105) attachment stage, position alignment, application of epoxy adhesive, insertion of fasteners (104), torque management, and position adjustment can be performed. In the waterproof and UV-blocking coating stage, epoxy or lacquer can be sprayed or applied to perform curing and gloss treatment. In the final quality inspection stage, dimensions, strength, surface quality, and part fastening status can be verified. In the recycling stage, processes such as collection after use, crushing, and circular re-molding can be applied.

[0214] In some embodiments of the present invention, the coffee grounds composite head (100) may be manufactured such that the particle size of the coffee grounds powder, mixing uniformity, minimization of bubbles, curing conditions, surface quality, component fastening rigidity, durability of the coating layer, and ease of recycling are managed. The particle size of the coffee grounds powder can be adjusted to an average of 50 to 500 micrometers and a relative standard deviation of 10% or less during the grinding and sieving process (Claim 2). Mixing uniformity can be ensured by controlling the stirring speed, time, and viscosity. Minimization of bubbles can be achieved by vacuum injection, addition of a defoaming agent, and the use of a vibrating table. Curing conditions can be optimized by setting profiles such as temperature, time, and humidity. Surface quality can be managed by mold surface roughness (0.8 to 0.05 μm) and CNC finishing. Component fastening rigidity can be ensured by managing the torque of the epoxy adhesive, bolts, and fasteners (104). The durability of the coating layer can be evaluated according to the type of coating agent, application thickness, and curing conditions. Recyclability can be enhanced through the selective application of material composition, bonding structure, and surface coatings.

[0215] In some embodiments of the present invention, the coffee grounds composite head (100) can achieve various functional characteristics, such as eco-friendliness, durability, shock absorption, center of gravity control, acoustic properties, and recyclability, during the manufacturing process. The coffee grounds composite head (100) can simultaneously secure eco-friendliness and durability through a combination of coffee grounds powder and synthetic resin. The coffee grounds composite head (100) can achieve shock absorption and center of gravity control functions by attaching a front reinforcing plate (102) (carbon fiber plate 6~8 mm) and a lower weight control plate (105) (multiple fastening grooves, variable front-rear position) (Claim 4, Claim 5, Claim 6, Claim 7). The coffee grounds composite head (100) can control shock dispersion and acoustic properties through an internal porous structure and rib and partition designs. The coffee grounds composite head (100) can provide various functions, such as waterproofing, UV protection, weather resistance, and gloss, through a surface coating layer (Claim 8). The coffee grounds composite head (100) can achieve sustainability through a recyclable structure that allows for crushing and remolding after use.

[0216] In some embodiments of the present invention, the pretreatment of coffee grounds raw materials may include recovery, sorting, drying, grinding, and sieving processes to use the coffee grounds as a composite material raw material for a park golf club head (100). The pretreatment of coffee grounds raw materials may proceed sequentially to maintain consistent quality of the coffee grounds. The pretreatment of coffee grounds raw materials may ensure freshness in the recovery stage, remove foreign substances in the sorting stage, and reduce moisture content in the drying stage. In the grinding and sieving stages, the particle size distribution may be homogenized to obtain powder suitable for the molding process. Each pretreatment stage may have a direct effect on the physical properties and molding quality of the final composite material.

[0217] According to some embodiments, the coffee grounds raw material pretreatment process may be intended to manage the particle size, moisture content, uniformity, and hygienic condition of the final powder. Through particle size control, the coffee grounds raw material pretreatment process can obtain a uniform powder with an average particle diameter of 50 to 500 micrometers and a relative standard deviation of 10% or less. Through drying and screening, the coffee grounds raw material pretreatment process can achieve a hygienic condition with a moisture content of 5% or less and an impurity content of 0.1% or less. To maintain hygienic conditions, the coffee grounds raw material pretreatment process can minimize the possibility of mold, odor, and microbial growth. The coffee grounds raw material pretreatment process can contribute to improving mold injection efficiency and the surface quality of the composite material during the molding process.

[0218] In some embodiments of the present invention, the coffee grounds recovery and sorting step may be a process of collecting coffee grounds in a fresh state from their source and ensuring quality by removing foreign substances and spoilage factors. In the coffee grounds recovery and sorting step, coffee grounds generated at cafes, coffee roasting plants, etc., can be quickly collected by placing them in designated containers. The recovered coffee grounds can be inspected for the presence of foreign substances immediately after collection using visual inspection or automated sensors. In the sorting step, non-organic foreign substances such as metal, plastic, and paper can be removed using magnetic separators, air blowers, sieves, etc. Spoilage factors can be sorted according to management standards such as moisture content, temperature, and time, allowing coffee grounds with a potential for mold growth to be separated separately. The recovery and sorting step may affect the hygiene and durability of the final composite material.

[0219] According to some embodiments, coffee grounds generated at cafes, coffee roasting plants, etc., can be collected. Coffee grounds can be collected regularly through a collection schedule designated for each source. When collecting coffee grounds, a dedicated airtight container can be used to prevent external contamination and moisture evaporation. Coffee grounds can be collected within 6 hours of generation to maintain freshness.

[0220] According to some embodiments, fresh coffee grounds spoil quickly, so they may be collected on the same day as a matter of principle. Fresh coffee grounds have a moisture content of 60% or more, which can lead to rapid spoilage. Collecting them on the same day may be essential to minimize the occurrence of mold and odors. The coffee grounds collected on the same day can be immediately transferred to a drying process to prevent quality degradation.

[0221] In some embodiments of the present invention, the recovered coffee grounds may undergo a sorting process to prevent contamination with foreign substances. The recovered coffee grounds may have foreign substances separated automatically or manually on a sorting line. The sorting process may involve spreading the coffee grounds thinly and sequentially applying a metal detector, a magnetic separator, an air blower, a sieve, etc.

[0222] In some embodiments of the present invention, inorganic foreign substances such as metal, plastic, and paper can be removed during the sorting process. Metal foreign substances can be separated using a magnetic separator. Plastic and paper foreign substances can be removed using a color recognition sensor or by manual labor. After the removal of foreign substances, the purity of the coffee grounds can be maintained at 99.9% or higher.

[0223] According to some embodiments, since coffee grounds have a high moisture content and spoil quickly, they can be introduced into a drying process immediately after collection to prevent the occurrence of mold and odors. Coffee grounds can be introduced into the drying process within 2 hours of collection to suppress the possibility of microbial growth. The drying process can be selected as natural drying or hot air drying. The occurrence of mold and odors can be minimized by controlling the drying temperature, time, and ventilation conditions. Hygiene can be enhanced by spraying an antibacterial agent or deodorizer before the drying stage.

[0224] According to some embodiments, the drying step may be a process to lower the moisture content of the coffee grounds to improve long-term storage and grinding efficiency. The drying step can reduce the moisture content of the coffee grounds from 60% or more to 5% or less. The drying step may be applied by selecting between natural drying and hot air drying. The drying step can improve grinding efficiency and prevent mold growth during long-term storage. The drying step may affect the mechanical strength and surface quality of the final composite material.

[0225] According to some embodiments, coffee grounds can be spread out and dried naturally for about 3 to 5 days. Coffee grounds can be spread thinly to a thickness of 2 to 3 cm and dried in a well-ventilated place. Natural drying allows for adjusting the drying time according to sunlight, wind, and temperature conditions. Natural drying reduces energy consumption and may be suitable for mass processing.

[0226] According to some embodiments, uniform drying can be achieved by turning the coffee grounds over frequently during natural drying. The coffee grounds can be turned over at intervals of 6 to 12 hours to minimize drying variations between the upper and lower layers. The turning operation can be performed using an automatic rotating device or manually. Uniform drying can contribute to ensuring consistency in particle size distribution during grinding.

[0227] In some embodiments of the present invention, coffee grounds can be dried at approximately 100 to 120°C for 1 to 2 hours using a dryer or a hot air dryer. Hot air drying is suitable for large-volume processing, and the temperature and time can be adjusted according to the initial moisture content of the coffee grounds. Hot air drying can be performed by spreading the coffee grounds thinly on a rotating drum or tray inside the dryer and circulating hot air. Hot air drying can rapidly lower the moisture content and inhibit the growth of microorganisms.

[0228] According to some embodiments, a rotating or stirring device may be used to ensure that heat is applied evenly to the coffee grounds during hot air drying. A rotary drum dryer can achieve uniform heat distribution by continuously rotating the coffee grounds. A stirring device can increase drying efficiency by dispersing the coffee grounds to prevent clumping. After hot air drying, the coffee grounds can undergo a cooling process to prevent moisture reabsorption.

[0229] According to some embodiments, the moisture content of the dried coffee grounds can be managed to be ultimately 5% or less. The moisture content can be measured by sampling after drying using an infrared moisture meter or a drying loss method. If the moisture content exceeds 5%, an additional drying process can be repeated. Coffee grounds with a moisture content of 5% or less are suitable for long-term storage and grinding processes.

[0230] According to some embodiments, moisture content measurement may be performed using an infrared moisture meter or a drying loss method. An infrared moisture meter can measure the amount of moisture evaporated by heating a coffee grounds sample at a certain temperature. The drying loss method can calculate the moisture content by calculating the weight loss after drying a certain amount of coffee grounds at 105°C for 2 hours. The results of the moisture content measurement may be stored in a quality control record.

[0231] According to some embodiments, the grinding and sieving steps may be a process of making dried coffee grounds into fine powder and homogenizing the particle size distribution. The grinding step may use fine grinding equipment to make the coffee grounds into powder with an average particle diameter of 50 to 500 micrometers. The sieving step may homogenize the particle size distribution by separating large particles and foreign substances using a sieve. The grinding and sieving steps may affect the mold injection efficiency and the surface texture of the composite material in the molding process.

[0232] In some embodiments of the present invention, dried coffee grounds can be ground into a fine powder using a fine grinding device. Various types of fine grinding devices may be applied, such as hammer mills, ball mills, and jet mills. During the grinding process, the particle size can be controlled according to the grinding speed, time, and type of equipment. The ground coffee grounds can be adjusted to an average particle diameter in the range of 50 to 500 micrometers.

[0233] According to some embodiments, stirring or vibration functions may be used to prevent clumping during the grinding process. The stirring device can continuously mix the coffee grounds to prevent them from clumping inside the equipment during grinding. The vibration function can improve the uniformity of particle distribution when the ground powder passes through a sieve. The combination of grinding, stirring, and vibration functions can improve the quality of the powder.

[0234] According to some embodiments, large particles or foreign substances can be filtered out from the ground coffee powder using a sieve. The sieve may be made of stainless steel to be hygienic and highly durable. The sieve can spread the powder to a uniform thickness and sift it using a vibration or rotational method. The sieving process can separate the powder by particle size to ensure a uniform particle size distribution.

[0235] According to some embodiments, the sieve specifications can be selected to match the average particle diameter range of 50 to 500 micrometers. The sieve specifications can be used in combination with various sizes, such as 50, 100, 200, 300, and 500 micrometers. The sieve specifications can be optimized according to the molding characteristics and surface quality of the final composite. Large particles remaining after sieving can be reintroduced into a re-grinding process.

[0236] According to some embodiments, sieved coffee grounds powder can be homogenized to a relative standard deviation of 10% or less. The particle size distribution can be measured using a laser particle size analyzer or a sieve analyzer. Powder with a relative standard deviation of 10% or less can ensure consistency in the mold filling rate and surface texture during the molding process. The homogenized powder can have a positive effect on the mechanical strength and durability of the composite material.

[0237] According to some embodiments, homogenized powder can affect mold injection efficiency and surface texture during the molding process. The homogenized powder can minimize bubble generation during mold injection and enable a fine texture on the surface of the composite material. The homogenized powder can improve viscosity and dispersibility when mixed with synthetic resin. The homogenized powder can contribute to the appearance quality and durability of the final park golf club head (100).

[0238] In some embodiments of the present invention, the composite material blending and extrusion process may be a process for manufacturing a composite material suitable for molding by uniformly mixing coffee grounds powder, a synthetic resin, and a binder. The composite material blending and extrusion process can ensure the homogeneity of the composite material by adjusting the particle size and moisture content of the coffee grounds powder in advance, and then mixing it with the synthetic resin and binder in a predetermined ratio. The composite material blending and extrusion process can achieve fluidity and surface quality suitable for molding by monitoring viscosity and the occurrence of bubbles in real time during the mixing process. The composite material blending and extrusion process can mold the mixed composite material into a desired shape by feeding it into an extruder or a mold. The composite material blending and extrusion process may apply a continuous process flow for mass production.

[0239] According to some embodiments, the composite blending and extrusion process can determine the physical properties and quality of the final molded product by managing the particle size, moisture content, mixing uniformity, viscosity, and bubble generation of the coffee grounds powder. The composite blending and extrusion process can adjust the average particle diameter of the coffee grounds powder to 50 to 500 micrometers and manage the moisture content to 5% or less. The composite blending and extrusion process can optimize the stirring speed, time, temperature, and mixer structure to ensure mixing uniformity. The composite blending and extrusion process can measure the viscosity of the mixture in real time using a viscometer and adjust the viscosity by adding additives if necessary. The composite blending and extrusion process can minimize bubble generation through vacuum stirring, addition of a defoaming agent, low-speed stirring, etc.

[0240] In some embodiments of the present invention, the composite blending and extrusion process may optionally include a fillet extrusion step to increase continuous productivity and mass production efficiency. The composite blending and extrusion process can form the mixed composite into a continuous strand shape through the fillet extrusion step. By cutting the continuous strand into a certain length and storing it in a fillet shape, the composite blending and extrusion process can improve the automation and productivity of subsequent forming processes. The composite blending and extrusion process can implement a process flow suitable for mass production by continuously performing the steps of extruder feeding, strand formation, cutting, and storage.

[0241] According to some embodiments, the synthetic resin and binder preparation step may serve as a basic process to secure the mechanical strength and durability of the composite material by combining it with coffee grounds powder. In the synthetic resin and binder preparation step, various synthetic resins such as epoxy resin, polyurethane resin, and polyvinyl alcohol may be selected to consider the compatibility of mixing with coffee grounds powder and curing characteristics. In the synthetic resin and binder preparation step, optimal mechanical strength and durability can be achieved by adjusting the ratios of curing agents, accelerators, and additives according to the type of resin. In the synthetic resin and binder preparation step, the viscosity, fluidity, and curing time of the resin may be measured in advance before mixing to minimize quality variations when mixed with coffee grounds powder.

[0242] According to some embodiments, synthetic resins such as epoxy resin, polyurethane resin, and polyvinyl alcohol may be used. The synthetic resin may be selected based on compatibility with coffee grounds powder, curing characteristics, moisture resistance, and durability. In the case of epoxy resin, it can provide excellent adhesion and chemical resistance, while polyurethane resin can impart elasticity and shock absorption properties. Polyvinyl alcohol may be selected considering reduced moisture absorption and eco-friendliness.

[0243] According to some embodiments, the synthetic resin may be selected based on its compatibility with coffee grounds powder, curing characteristics, moisture resistance, and durability. The compatibility of the synthetic resin may vary depending on the surface treatment state and particle size of the coffee grounds powder. The synthetic resin may be classified and applied as a room-temperature curing type, a heat-curing type, etc., depending on its curing characteristics. To improve moisture resistance, the synthetic resin may be used in combination with silane treatment or weather-resistant additives.

[0244] According to some embodiments, during the preparation stage of the synthetic resin and binder, the addition ratio of the curing agent can be adjusted according to the type of resin and the mixing ratio. For epoxy resins, the curing agent ratio can be adjusted to a range of 100:10 to 100:20 (resin:curing agent), and for polyurethane resins, it can be mixed according to the manufacturer's recommended ratio. The curing agent ratio can be measured using a precision scale before mixing. After mixing, the curing reaction rate may vary depending on the stirring time and temperature.

[0245] According to some embodiments, the curing agent ratio can affect the curing speed, final strength, moisture resistance, and molding stability of the composite. If the curing agent ratio is excessively high, the curing reaction proceeds rapidly, which may lead to bubble formation and surface defects. If the curing agent ratio is insufficient, poor curing, reduced mechanical strength, and reduced moisture resistance may occur. The curing agent ratio can act as an important variable in ensuring the dimensional stability and durability of the final molded product.

[0246] In some embodiments of the present invention, a defoaming agent may be added during the synthetic resin and binder preparation step to minimize bubbles that may occur during the mixing process. Various types of defoaming agents, such as silicone-based, polysiloxane-based, and alcohol-based agents, may be used and selected according to the type of resin and the mixing ratio. The defoaming agent may be added to the mixture in a range of 0.1 to 1.0 weight percent to suppress bubble generation. The defoaming agent may help fine bubbles rise and be discharged to the surface during the stirring process after mixing.

[0247] In some embodiments of the present invention, a defoaming agent can improve the surface quality and mechanical properties of a molded article by suppressing the generation of bubbles within the composite material. Due to the addition of a defoaming agent, the surface of the molded article can be manufactured to be smooth and free of defects. The defoaming agent can contribute to improving the physical properties of the composite material, such as mechanical strength, durability, and moisture resistance. The defoaming agent can help maintain shock absorption and durability by lowering the internal porosity of the molded article.

[0248] According to some embodiments, the uniform mixing step with coffee grounds may be a process for ensuring the homogeneity of the composite material by mixing coffee grounds powder, synthetic resin, and binder in a constant ratio. The uniform mixing step with coffee grounds may involve adjusting the particle size distribution and moisture content of the coffee grounds powder in advance, and then weighing and mixing it with the synthetic resin and binder using a precision scale. The uniform mixing step with coffee grounds may involve stirring at a constant speed and time using a mixer or agitator to ensure that the coffee grounds powder is evenly dispersed within the resin. The uniform mixing step with coffee grounds may involve observing the viscosity, fluidity, and bubble formation of the mixture in real time, and adjusting the quality by adding additives or changing stirring conditions as necessary.

[0249] According to some embodiments, ground and sieved coffee grounds can be mixed with a binder. The ground and sieved coffee ground powder can be mixed with the binder in a state where the particle size and moisture content are uniformly adjusted. The temperature and viscosity of the coffee ground powder and the binder are measured before mixing, thereby minimizing quality variations during mixing.

[0250] According to some embodiments, the mixture must be stirred to ensure uniform mixing and prevent foaming. During the mixing process, low-speed stirring can be applied to suppress bubble formation. The mixer may have various structures, such as paddle, spiral, or planetary types, and can be selected based on the viscosity and particle distribution of the mixture.

[0251] According to some embodiments, stirring conditions can be optimized based on mixing speed, time, temperature, and the type of stirrer. For example, the mixing speed can be adjusted in the range of 30 to 100 rpm, and the stirring time can be set to 10 to 30 minutes. The mixing temperature can be maintained in the range of 20 to 40°C to increase the fluidity of the resin and the dispersibility of the coffee grounds powder. The type of stirrer can be selected as a paddle type or a planetary type depending on the viscosity and particle size of the mixture.

[0252] According to some embodiments, the viscosity of the mixture of coffee grounds and synthetic resin can be controlled to maintain a viscosity suitable for molding and extrusion. Viscosity control can directly affect the fluidity, mold injectability, and suitability for extrusion molding of the mixture. Viscosity control can be adjusted according to various variables, such as the content of coffee grounds powder, the type of synthetic resin, the ratio of additives, and the mixing temperature.

[0253] In some embodiments of the present invention, viscosity can be controlled according to the content of coffee grounds powder, the type of resin, temperature, and additives. For example, as the viscosity increases as the content of coffee grounds powder increases, fluidity can be compensated for by increasing the viscosity of the resin or adding additives. Viscosity can be measured in real time using a viscometer (e.g., a rotational viscometer). Viscosity can be managed in the range of 1,000 to 10,000 cP during the molding and extrusion processes.

[0254] According to some embodiments, process conditions may be applied during the uniform mixing step to minimize bubbles that may occur during the mixing process. To minimize bubbles, methods such as vacuum stirring before and after mixing, low-speed stirring, and the addition of a defoaming agent may be applied. Minimizing bubbles can play an important role in ensuring the surface quality, mechanical strength, and durability of the molded product.

[0255] In some embodiments of the present invention, methods such as vacuum stirring, addition of a defoaming agent, and low-speed stirring may be used to minimize bubbles. Vacuum stirring can reduce internal porosity by expelling bubbles from the mixture to the outside. Addition of a defoaming agent can reduce surface defects by promoting the aggregation and ascent of microbubbles. Low-speed stirring can suppress the influx of unnecessary air during the mixing process.

[0256] In some embodiments of the present invention, the method for manufacturing a park golf club head may further include a first vacuum degassing step and a second vacuum degassing step to effectively remove bubbles generated during the mixing process.

[0257] According to one embodiment, the mixed material is first fed into a primary vacuum degassing machine, where internal bubbles can expand, rise, and move to the surface. The primary vacuum degassing machine may include a chamber, a vacuum pump, a stirrer, and a viewing window, and the stirring speed can be automatically adjusted when a target vacuum level is reached through a pressure sensor and control logic. Additionally, overflow can be prevented by ensuring sufficient container height or installing a level sensor, taking into account the expansion amount of the mixture. The mixture, after the primary degassing is completed, is stored in a temporary storage and transfer device and can be automatically transferred to a secondary vacuum degassing machine while maintaining uniformity through a stirrer.

[0258] According to one embodiment, the secondary vacuum degassing unit is designed with a lower vessel height (e.g., 100 to 150 mm or less) than the primary degassing unit to shorten the rising distance of bubbles and increase discharge efficiency. Additionally, by equipping a pressure reducing valve and a rotary stirrer, residual fine bubbles can be further removed, and pressure, temperature, and stirring speed conditions can be precisely controlled. For example, if conditions of 50 kPa, 25°C, and 20 minutes are applied in the primary degassing, residual bubbles can be removed by adjusting the conditions to 20 kPa, 35°C, and 15 minutes in the secondary degassing. Through this, the residual bubble rate in the mixture can be reduced to 1% or less, and surface defects in the final molded product can be suppressed.

[0259] According to some embodiments, the secondary vacuum degassing system may include a vacuum chamber, a pressure reducing valve, and a rotary stirrer. The vacuum chamber is made of a durable material such as stainless steel and is equipped with a viewing window to observe the bubble removal process in real time. The pressure reducing valve is linked with an electronic control module to control the pressure in increments of 1 kPa within the range of 0 to 100 kPa. The rotary stirrer can adjust the stirring speed and blade shape according to the viscosity of the mixture and can automatically control the intensity by including a torque sensor.

[0260] In some embodiments of the present invention, quality inspection may include the viscosity of the mixture, the residual bubble rate, and the presence of foreign substances. The mixture is transferred to a secondary degassing machine only when the quality inspection results, obtained through a viscometer, optical sensor, metal detector, etc., satisfy a standard value, and if the results do not meet the standard, the mixture may undergo a re-stirring or re-degassing process.

[0261] In some embodiments of the present invention, a mixture that has undergone a two-stage vacuum degassing process suppresses irregularities, pinholes, and whitening caused by bubbles, thereby improving the appearance quality of the molded product. In addition, by preventing residual bubbles from acting as stress concentration points, tensile strength, impact strength, and fatigue life can be improved. For example, a composite head to which secondary vacuum degassing is applied may have cracks or failures delayed even in repeated load tests, and its durability may be significantly improved.

[0262] In some embodiments of the present invention, the fillet extrusion step may be an optional process for forming a mixed composite material into a continuous strand using an extruder. The fillet extrusion step may continuously form a strand of a certain diameter by feeding the mixed composite material into an extruder hopper and undergoing heating and extrusion processes. The fillet extrusion step may maintain a uniform diameter and density of the strand by adjusting process conditions such as extrusion temperature, extrusion speed, and die diameter. By cutting the continuous strand into a certain length and storing it in the form of a fillet, the fillet extrusion step can increase the automation and productivity of subsequent forming processes.

[0263] In some embodiments of the present invention, coffee grounds mixed with synthetic resin can be fed into an extruder. In the extruder feeding step, the viscosity, temperature, feed rate, etc., of the mixture can be measured in advance to increase the efficiency of transfer and heating within the extruder. When feeding into the extruder, the mixture can be automatically supplied in fixed amounts through a hopper.

[0264] According to some embodiments, the viscosity, temperature, and feed rate of the mixture can be controlled when fed into the extruder. The viscosity of the mixture can affect the transfer resistance within the extruder and the quality of strand formation. The temperature of the mixture can be maintained in the range of 40 to 80°C in the extruder heating section. The feed rate can be adjusted in the range of 0.5 to 2.0 kg / h depending on the extruder capacity and strand diameter.

[0265] According to some embodiments, the mixture can be formed into a long, continuous strand like taffy in an extruder. In the continuous strand forming step, the mixture can be drawn out through an extruder die to a constant diameter. The surface temperature of the continuous strand can be rapidly lowered using a cooling conveyor or an air blower.

[0266] In some embodiments of the present invention, the extrusion conditions of the continuous strand can be adjusted to maintain a constant diameter and uniform density. The diameter of the extruder die can be set to a range of 5 to 20 mm, and the density of the strand can be adjusted according to the viscosity of the mixture and the extrusion speed. The pressure and temperature inside the extruder can be monitored in real time to ensure that the continuous strand is free from surface defects.

[0267] In some embodiments of the present invention, a continuous strand can be cut to a required length and stored in the form of fillets. The cutting step may involve using an automatic cutter to cut the strand to a length of 10 to 50 cm. After inspecting the surface quality and dimensional accuracy of the cut fillets, they can be stored in a dedicated container.

[0268] According to some embodiments, the surface quality, dimensional accuracy, and storage conditions of the fillet can be managed during the cutting and storage stages. The surface quality of the fillet can be verified by visual inspection and a surface roughness measuring instrument. Dimensional accuracy can be managed using vernier calipers or automatic measuring equipment. Storage conditions can be maintained within the range of a temperature of 15 to 25°C and a relative humidity of 40 to 60% to minimize quality variation.

[0269] According to some embodiments, mold design and injection may be a core process for molding a coffee grounds powder and synthetic resin composite into a final shape. Mold design and injection can be a key step in determining the fluidity, curing characteristics, and surface quality of the composite. Mold design and injection can ensure dimensional stability and repeatability of the composite based on the precision of the metal outer die and silicone mold. Mold design and injection may include a series of process flows from injection of the composite mixture, bubble removal, curing, and demolding.

[0270] According to some embodiments, mold design and injection may include metal outer mold fabrication, silicon mold formation, composite material injection, and bubble removal steps. Mold design and injection can determine the external shape during the metal outer mold fabrication step and precisely replicate the internal shape during the silicon mold formation step. Mold design and injection can inject a mixture into the mold during the composite material injection step and minimize internal bubbles by utilizing vacuum or vibration during the bubble removal step. Mold design and injection can improve the quality of the final molded product by controlling process conditions such as temperature, time, and pressure at each step.

[0271] In some embodiments of the present invention, the production of a metal outer mold may be a process that determines the external shape of a silicon mold and influences molding quality and repeatability. The production of the metal outer mold can precisely realize the outer shape and dimensions of a park golf club head (100). The production of the metal outer mold can be designed to have sufficient rigidity and durability to prevent deformation during the curing and demolding of the silicon mold. The production of the metal outer mold minimizes wear and deformation due to repeated use, thereby enabling the production of a large number of molded products of the same quality.

[0272] According to some embodiments, the metal outer die manufacturing step may use aluminum or carbon steel as a material considering precision and machinability. If aluminum is used in the metal outer die manufacturing step, the heat dissipation effect can be enhanced due to its excellent lightness and thermal conductivity. If carbon steel is used in the metal outer die manufacturing step, it may be suitable for long-term repeated use due to its high wear resistance and strength. The metal outer die manufacturing step can manage dimensional errors to 0.05 mm or less by utilizing high-precision machining equipment such as CNC machining or electrical discharge machining.

[0273] In some embodiments of the present invention, the metal outer die manufacturing step may utilize high-precision machining equipment to ensure dimensional accuracy and repeatability during composite molding. The metal outer die manufacturing step may design the die machining path based on 3D CAD data. The metal outer die manufacturing step may verify quality through dimensional measurement and surface inspection after machining. The metal outer die manufacturing step may monitor the wear status of the cutting tool and the machining speed in real time to ensure machining precision.

[0274] In some embodiments of the present invention, the metal outer die manufacturing step may perform polishing to improve the quality and molding performance of the die. The metal outer die manufacturing step may remove fine scratches and machining marks from the die surface through polishing. The metal outer die manufacturing step may predict the surface quality of the molded product by measuring the surface roughness after polishing.

[0275] In some embodiments of the present invention, the metal outer mold manufacturing step may have a polishing roughness of 0.8 to 0.05 micrometers or less. If the surface roughness of the metal outer mold manufacturing step is set to 0.8 micrometers or less, the surface of the molded product can be made smooth. If the metal outer mold manufacturing step applies ultra-precision polishing at the 0.05 micrometer level, a molded product with excellent gloss can be obtained. Depending on the surface roughness of the metal outer mold manufacturing step, the replication precision of the silicone mold and the surface texture of the final composite head (100) may vary.

[0276] According to some embodiments, the metal outer die manufacturing step can be designed considering durability and lifespan due to repeated use. The metal outer die manufacturing step can extend the life of the die by applying a wear-resistant coating or surface hardening treatment. The metal outer die manufacturing step can introduce a structure that disperses heat and stress generated during the repeated hardening and demolding processes.

[0277] According to some embodiments, the metal outer mold manufacturing step may include a heat dissipation structure to effectively dissipate heat generated during molding. The metal outer mold manufacturing step may apply various heat dissipation structures, such as heat dissipation fins, heat dissipation holes, and the insertion of thermally conductive materials. Through the heat dissipation structure, the metal outer mold manufacturing step can maintain a constant internal mold temperature during the curing process. If the heat dissipation performance of the metal outer mold manufacturing step is improved, the curing speed and quality of the molded product can be maintained stably.

[0278] According to some embodiments, silicone mold forming may be a process of injecting silicone into a metal outer mold to produce an inner mold suitable for molding composites. Silicone mold forming can precisely replicate the internal shape of the metal outer mold, enabling the realization of detailed shapes during composite molding. The curing time for silicone mold forming can be controlled at room temperature or low temperature depending on the curing characteristics of the silicone. Silicone mold forming can ensure dimensional stability and ease of demolding of the mold after curing.

[0279] In some embodiments of the present invention, the silicone mold forming step may mix silicone molding agents (silicone agent A + agent B) for detailed shape replication. The silicone mold forming step may mix silicone agent A and agent B in a predetermined ratio to ensure that the curing reaction occurs uniformly. Since curing defects or mold deformation may occur if the mixing ratio is not accurate, an electronic scale or an automatic mixer may be used in the silicone mold forming step.

[0280] In some embodiments of the present invention, the silicone mold forming step can optimize curing characteristics by mixing silicone A and B according to the manufacturer's recommended ratio. The silicone mold forming step can control the hardness and flexibility of the mold by adhering to the mixing ratio suggested by the manufacturer (e.g., 10:1, 20:1, etc.). The silicone mold forming step can minimize bubble formation by injecting the mixture into a metal outer mold immediately after mixing. The durability and reusability of the mold may vary depending on the mixing ratio and curing conditions of the silicone mold forming step.

[0281] According to some embodiments, the silicone mold forming step may involve injecting the mixed silicone into a metal outer mold and then curing it at room temperature or a low temperature. The silicone mold forming step may increase the dimensional stability of the mold by maintaining the curing temperature at 20 to 30°C. If low-temperature curing is required, the curing speed of the silicone mold forming step may be controlled by utilizing a cooling device.

[0282] According to some embodiments, the silicone mold forming step can ensure dimensional stability and surface quality of the mold by controlling the curing time and temperature. The silicone mold forming step can minimize internal stress and shrinkage deformation of the mold by setting the curing time to a range of 6 to 24 hours. The silicone mold forming step can inspect the surface quality of the mold after curing to check for the presence of micro-defects or bubbles. The number of times the mold can be reused and its durability may vary depending on the curing conditions of the silicone mold forming step.

[0283] According to some embodiments, the silicon mold forming step can precisely replicate the fine shape of a metal outer mold. The silicon mold forming step can transfer the surface roughness and fine pattern of the metal outer mold directly to the silicon mold. To increase replication precision, the silicon mold forming step can inject silicon under vacuum.

[0284] According to some embodiments, the silicone mold forming step can accurately realize the detailed shape and surface texture of the head (100) during composite molding. The silicone mold forming step can realize various shapes, such as fine grooves, curved surfaces, and textures, inside the mold. The silicone mold forming step can prevent deformation or shrinkage of the mold during composite injection, thereby minimizing dimensional errors of the final molded product. The silicone mold forming step can enhance the design diversity and functionality of the park golf club head (100) through the replication of detailed shapes.

[0285] According to some embodiments, injection and bubble removal may be a process of injecting a composite mixture into a mold and minimizing internal bubbles to improve molding quality. In injection and bubble removal, the injection speed and pressure can be adjusted to ensure that the mixture is filled without gaps within the mold, taking into account the viscosity and fluidity of the composite mixture. Various methods, such as vacuum injection, vibrating tables, and the addition of defoaming agents, can be applied to suppress bubble formation. Since the presence of remaining bubbles may lead to a decrease in the strength of the molded product or surface defects, real-time monitoring and quality inspection may be performed in parallel.

[0286] In some embodiments of the present invention, the injection and bubble removal step may inject the finished mixture into a metal outer mold and a silicon mold structure. The injection and bubble removal step may create a vacuum inside the mold before injecting the mixture to block the inflow of air. The injection and bubble removal step may use a vacuum pump to lower the internal pressure of the mold to a level of 10 to 100 hPa.

[0287] According to some embodiments, the injection and bubble removal step may utilize a vacuum state to prevent the formation of bubbles. The injection and bubble removal step allows the composite material to uniformly fill all spaces within the mold using a vacuum injection method. When the injection and bubble removal step is performed under vacuum, microbubbles are naturally removed, which can improve the strength and surface quality of the molded product. The injection and bubble removal step can prevent shrinkage or deformation of the composite material by gradually restoring the internal pressure of the mold after vacuum injection.

[0288] In some embodiments of the present invention, the injection and bubble removal step can effectively remove bubbles within the mixture by utilizing a vibrating table. In the injection and bubble removal step, when the mold is placed on the vibrating table and injection is performed, bubbles within the mixture can rise to the top due to vibration. The injection and bubble removal step can be applied to composites of various viscosities by adjusting the vibration frequency and amplitude. In the injection and bubble removal step, a surface scraper or tweezers may be used to remove bubbles remaining on the mold surface after using the vibrating table.

[0289] According to some embodiments, the injection and bubble removal step can be managed to ensure that the composite material is filled without gaps by monitoring the filling rate within the mold in real time. The injection and bubble removal step can visually check the filling status using a transparent mold or an endoscope camera. If the filling rate is less than 95%, the injection and bubble removal step can perform additional injection to minimize empty space within the mold.

[0290] In some embodiments of the present invention, the injection and bubble removal step can prevent overfilling or underfilling to stably secure the dimensions and physical properties of the final molded product. The injection and bubble removal step can measure the injection amount using an electronic scale and adjust it to match the mold volume. The injection and bubble removal step can design an injection port and an exhaust port to prevent mold deformation or composite material leakage in the event of overfilling. The injection and bubble removal step can control the injection speed and pressure to prevent internal defects in the molded product in the event of underfilling.

[0291] According to some embodiments, curing, demolding, and post-processing may be key processes for securing the final physical properties and determining the appearance finish of a head (100) molded from coffee grounds powder and a synthetic resin composite. Curing, demolding, and post-processing may ultimately determine the mechanical strength, dimensional stability, and surface quality of the composite head (100). Curing, demolding, and post-processing may sequentially include a series of steps such as curing within a mold, demolding of a molded product, and CNC machining. Curing, demolding, and post-processing can minimize product quality variations by precisely controlling the temperature, time, and processing conditions at each step.

[0292] According to some embodiments, curing, demolding, and post-processing may include steps of curing the composite material within the mold, demolding the molded product, and ensuring dimensional and surface precision through CNC machining. In the curing step, the composite mixture can achieve final strength by undergoing a chemical or physical curing reaction within the mold. In the demolding step, the cured molded product can be separated from the mold without damage. In the CNC machining step, the appearance and assembly precision can be enhanced through various post-processing steps, such as planar machining, edge rounding, and dimensional precision correction.

[0293] In some embodiments of the present invention, the curing process may be a step that enables the composite mixture to achieve final strength and dimensional stability within the mold. The curing process may involve the chemical bonding of the synthetic resin curing agent and the coffee grounds powder to form structural integrity of the composite. The mechanical properties and internal pore structure of the composite may vary depending on the temperature, humidity, and curing time within the mold during the curing process. The curing process may be applied by selecting between room temperature curing or thermal curing methods.

[0294] According to some embodiments, room temperature curing may be a method in which the composite material in the mold is left to cure at natural temperature for a certain period of time. In room temperature curing, the composite material may gradually cure for 12 to 48 hours at room temperature (e.g., 20 to 25°C). Room temperature curing does not require an external heat source, so energy consumption can be reduced.

[0295] According to some embodiments, room temperature curing may be applied when heat-sensitive additives or components with low heat resistance are included. For example, in the case of composites containing natural fiber reinforcements or antimicrobial additives, deterioration of the components can be prevented through the room temperature curing method. Room temperature curing may also be applied to composites containing weather-resistant additives or silane treatment agents.

[0296] In some embodiments of the present invention, thermal curing may be a method of applying external heat to a composite material in a mold to increase the curing speed and ensure uniformity of physical properties. Thermal curing may be performed by curing the composite material in an oven or a hot air blower at a temperature of 40 to 80°C for 2 to 6 hours. Thermal curing can promote the curing reaction to minimize internal pore formation or shrinkage deformation.

[0297] According to some embodiments, heat curing can be performed using various heat source equipment such as ovens, hot air blowers, and infrared heaters. For example, in a large-scale production process, a conveyor oven can be used to continuously cure the composite head (100). In a small-scale production, individual curing for each mold is possible using an infrared heater.

[0298] In some embodiments of the present invention, the time and temperature profiles of the curing process can be optimized according to the type of composite material, the mold material, and the thickness of the molded product. For example, the curing time may be extended for a head (100) with a thickness of 30 mm or more, and the temperature may be adjusted considering the thermal conductivity characteristics when the mold material is silicone. The time and temperature profiles may be set in stages to prevent the formation of bubbles or shrinkage deformation within the composite material.

[0299] In some embodiments of the present invention, curing time and temperature may affect the mechanical strength, dimensional stability, and internal pore formation of the composite material. For example, if the curing temperature is too high, the internal pores may expand excessively, which may reduce strength. If the curing time is insufficient, the curing of the synthetic resin may be incomplete, leading to dimensional errors.

[0300] In some embodiments of the present invention, the park golf club head may further include a heat curing step to improve strength, hardness, and weather resistance after natural curing. The heat curing step promotes cross-linking of the resin inside the molded body, thereby increasing surface hardness and mechanical strength, and improving dimensional stability against moisture and temperature changes.

[0301] The molded body, after natural curing is complete, can be transferred to a heat curing device. During this process, the molded body is stored at a temperature of 20 to 30°C and a relative humidity of 40 to 60% to prevent quality degradation caused by surface drying, contamination with foreign substances, oxidation, etc. During the transfer process, a sealed container or an automatic transfer system can be applied, and if necessary, nitrogen gas can be injected to suppress the adsorption of oxygen and moisture. In addition, temperature and humidity sensors can be installed to enable real-time monitoring.

[0302] In some embodiments, heat curing may be performed using a hot air method, an infrared method, or a combination thereof. The heat curing oven may include a chamber, a heating element, a multi-point temperature sensor, a circulation fan, and a controller, and may be controlled so that the deviation within the chamber from the target temperature is maintained within ±2 to 5°C. Heat curing conditions can generally be applied at a temperature of 100 to 140°C and a time of 2 to 6 hours, and may vary depending on the thickness, volume, and resin composition. For example, a head with a thickness of 20 mm may undergo heat curing at 120°C for 4 hours, a head with a thickness of 10 mm may undergo heat curing at 120°C for 2 hours, and a head with a thickness of 25 to 30 mm may undergo heat curing at 125 to 130°C for 5 to 6 hours. During heat curing, the circulation fan may disperse hot air upward, downward, and sideways to maintain a uniform internal temperature, and the temperature difference between areas may be corrected through the multi-point temperature sensor. In addition, for thick products, a ramp-up method that gradually increases the temperature can be applied to prevent internal stress or the recurrence of bubbles.

[0303] After heat curing is complete, surface hardness, mechanical strength, and weather resistance can be evaluated. Surface hardness can be measured using a Shore D hardness tester, and, for example, a level of 80 to 85 Shore D can be achieved. Mechanical strength can be verified through tensile tests, bending tests, impact tests, etc., and tensile strength can be achieved at a level of 40 to 50 MPa. Weather resistance can be evaluated through temperature and humidity cycle tests or UV tests, and, for example, no deformation or cracking can occur even in weather resistance tests of 500 hours or more.

[0304] In addition, the heat curing process can be optimized to improve productivity and energy efficiency. Since thin products can be sufficiently cured in a short time, unnecessary long curing times should be avoided, while for thick products, a time limit or a slightly higher temperature can be applied to ensure complete curing to the inside. For example, it may be appropriate to apply heat curing for 2 to 3 hours at 120°C for products with a thickness of 8 to 12 mm, for 3.5 to 4.5 hours at 120°C for products with a thickness of 15 to 22 mm, and for 5 to 6 hours at 125 to 130°C for products with a thickness of 25 to 30 mm.

[0305] Finally, after heat curing is complete, components are attached under specified torque conditions to ensure the fastening rigidity of the front reinforcement plate and the lower weight adjustment plate, and waterproof and UV-blocking coatings are applied to enhance durability against external environments. If necessary, the surface can be finely polished to improve the adhesion of the coating; through these processes, a park golf club head with improved durability, shock absorption, center of gravity stability, and weather resistance can ultimately be realized.

[0306] In some embodiments of the present invention, demolding may be a step of separating a cured composite head (100) from a mold to enable subsequent processing. In the demolding step, the separation direction and separation speed may be controlled according to the structure of the mold and the shape of the molded product. In demolding, a dedicated tool and a release agent may be used to prevent surface damage or deformation of the molded product.

[0307] According to some embodiments, silicone mold separation may be a process of carefully separating the cured composite head (100) from the silicone mold. The silicone mold has excellent elastic recovery, so even complex shapes of the molded product can be separated without damage. When separating the silicone mold, the outer edge of the mold can be slowly spread open to gradually separate the inner molded product.

[0308] In some embodiments of the present invention, the silicone mold separation can be designed to enable demolding without damaging the molded product by utilizing the elastic restoring force of the mold. For example, even if there are curved surfaces or undercuts inside the mold, the molded product can be safely separated by utilizing the elasticity of the silicone mold. The separation angle and force of the silicone mold separation can be adjusted considering the durability of the mold during repeated use.

[0309] In some embodiments of the present invention, the damage prevention procedure may include a work sequence and the application of tools to prevent surface scratching, edge breakage, and structural deformation of the composite head (100) during demolding. The damage prevention procedure may minimize adhesion between the molded product and the mold by applying a mold release agent in advance. The damage prevention procedure may separate the molded product with uniform force using a dedicated demolding tool.

[0310] In some embodiments of the present invention, damage prevention procedures may apply various methods, such as using a mold release agent, introducing a dedicated demolding device, or low-speed separation. For example, when demolding a curved section, the outer edge of the silicone mold can be pressed by hand while separating slowly. The low-speed separation method can prevent fine cracks or scratches from occurring on the surface of the molded product.

[0311] In some embodiments of the present invention, the initial quality inspection may be a step of checking the appearance, dimensions, surface defects, and presence of bubbles of the molded product immediately after demolding. The initial quality inspection may be performed through various methods, such as visual inspection, dimensional measurement, and surface tactile verification. The initial quality inspection can identify defects such as bubbles, cracks, deformation, and contamination at an early stage.

[0312] According to some embodiments, initial quality inspection can contribute to the early screening of defective products and the improvement of efficiency in subsequent processing steps. For example, molded parts with dimensional errors outside the acceptable range may be classified as subjects for separate correction or re-molding. If surface defects are detected, additional polishing or surface treatment processes may be applied.

[0313] According to some embodiments, CNC finishing may be a post-processing step to improve the external shape precision and surface quality of the demolded composite head (100). CNC finishing can precisely machine various parts of the composite head (100), such as flat surfaces, curved surfaces, and joints (103), using a 3-axis or 5-axis CNC machine. CNC finishing can finely adjust surface roughness and dimensional errors depending on the machining path and tool selection.

[0314] In some embodiments of the present invention, planar machining may be a process of precisely machining major planes, such as the bottom surface and top surface of the head (100), using CNC equipment. Planar machining can correct minute deformations or dimensional errors that may occur during the molding process. Planar machining can ensure flatness of parts requiring assembly, such as the shaft coupling part (103) and the weight adjustment plate (105) attachment part of the head (100).

[0315] In some embodiments of the present invention, planar processing can correct for minute deformations or dimensional errors that may occur during the molding process. For example, the flatness of the bottom surface can be adjusted to 0.1 mm or less to increase the adhesion of the weight adjustment plate (105). The verticality of the shaft coupling part (103) can be secured through planar processing of the top surface.

[0316] In some embodiments of the present invention, corner rounding may be a process of processing the corner portion of the head (100) into a curved or rounded shape to prevent breakage and improve grip. Corner rounding can be performed by using a CNC rounding cutter to process the corner to a certain radius (R value). Corner rounding can increase safety by removing sharpness from the part that comes into contact with the user's hand.

[0317] According to some embodiments, corner rounding can contribute to improving user safety and product durability. For example, the rounding radius of the lower corner can be set to 2 to 5 mm to reduce the risk of damage upon impact. Rounding of the upper corner can improve grip and reduce user fatigue.

[0318] According to some embodiments, dimensional precision correction may be a process of minimizing errors in key parts, such as the overall dimensions of the head (100), the position of the joint part (103), and the hole of the fastener (104), through CNC machining. Dimensional precision correction can be performed by using a 3D measuring instrument to check dimensional errors in real time after machining. Dimensional precision correction can ensure assembly precision by matching the position and size of the joint part (103) to within ±0.05 mm.

[0319] In some embodiments of the present invention, dimensional precision correction can ensure compatibility with the shaft coupling part (103), weight adjustment plate (105) attachment part, etc., during final assembly. For example, the inner diameter of the shaft coupling part (103) can be machined to 12.0 ± 0.05 mm to maintain a constant coupling force with the shaft (120). The position of the fastening member (104) of the weight adjustment plate (105) attachment part can be aligned within ±0.1 mm to minimize errors during repeated assembly.

[0320] According to some embodiments, component attachment and surface coating may be post-processing steps to improve the durability, functionality, and appearance quality of the composite head (100). Component attachment and surface coating can increase the mechanical strength and weather resistance of the composite head (100). Component attachment and surface coating can maintain the uniform appearance quality of the head (100) and prevent damage or deformation that may occur during use. Component attachment and surface coating can expand the functional characteristics of the composite head (100) in various ways through the application of a front reinforcing plate (102), a lower weight adjustment plate (105), and a waterproof and UV-blocking coating layer.

[0321] In some embodiments of the present invention, component attachment and surface coating may include steps of attaching a front reinforcing plate (102), installing a lower weight adjustment plate (105), and forming a waterproof and UV-blocking coating layer. Separate work processes and quality control procedures may be applied to each step of component attachment and surface coating. For example, the attachment of the front reinforcing plate (102) may proceed in the order of applying adhesive, position alignment, compression and curing, insertion of a fastener (104), and quality check. The installation of the lower weight adjustment plate (105) may include steps of inserting a fastener (104), torque management, and position adjustment. The formation of a waterproof and UV-blocking coating layer may be performed in the order of selecting a coating agent, spraying or application, curing, and polishing.

[0322] According to some embodiments, the attachment of the front reinforcing plate (102) may be a process of attaching a reinforcing plate to the front of the head (100) to reinforce shock absorption and rebound force. The attachment of the front reinforcing plate (102) can disperse the impact energy generated during striking by precisely placing the reinforcing plate at a designated location on the front of the head (100). The characteristics of shock absorption and rebound force may vary depending on the material, thickness, and attachment method of the reinforcing plate. For example, the reinforcing plate may be designed as a flat plate structure covering the entire front of the head (100) to minimize deformation of the hitting surface and increase rebound force.

[0323] According to some embodiments, the front reinforcing plate (102) may be attached by applying a carbon fiber plate with a thickness of 6 to 8 mm and attaching it detachably using an adhesive and a fastener (104). The front reinforcing plate (102) may be attached by applying epoxy adhesive and then pressing the reinforcing plate against the front surface of the head (100) to secure it in the first place. The front reinforcing plate (102) may be attached by secondarily forming a mechanical connection by inserting a fastener (104), such as a bolt, screw, or pin. The front reinforcing plate (102) may be designed so that the position and number of fasteners (104) are adjusted to facilitate easy attachment and replacement of the reinforcing plate.

[0324] According to some embodiments, the position alignment of the front reinforcing plate (102) may be a step of accurately aligning the reinforcing plate to a designated attachment position on the front of the head (100). The position alignment of the front reinforcing plate (102) may be aligned so that the plane of the reinforcing plate is parallel to the reference plane on the front of the head (100). The position alignment of the front reinforcing plate (102) may minimize errors by utilizing auxiliary tools such as position marking lines, guide pins, and alignment jigs.

[0325] In some embodiments of the present invention, in the position alignment step, the plane of the reinforcing plate and the reference plane of the front of the head (100) can be aligned. In the position alignment step, the position can be adjusted so that the center point of the reinforcing plate and the center point of the front of the head (100) coincide. In the position alignment step, the edge of the reinforcing plate and the boundary line of the front of the head (100) can be precisely positioned so that they maintain a constant distance.

[0326] In some embodiments of the present invention, the compression and curing step may be a process of pressing the reinforcing plate against the head (100) and applying pressure to ensure that the adhesive is completely cured. The compression and curing step may maintain a constant thickness of the adhesive by applying uniform pressure to the front reinforcing plate (102). The compression and curing step may maintain the state in which the reinforcing plate and the head (100) are in close contact for a certain period of time using dedicated press equipment or a clamp.

[0327] In some embodiments of the present invention, compression and curing can secure bonding strength by controlling the curing time and temperature of the epoxy adhesive. Compression and curing can obtain optimal bonding strength by maintaining the curing temperature of the epoxy adhesive at 20 to 30°C and setting the curing time to 6 to 24 hours. Compression and curing can minimize the occurrence of defects at the adhesive interface by preventing external vibrations or shocks during the curing process.

[0328] According to some embodiments, the quality verification step may be a procedure for inspecting the attachment status, positional accuracy, bonding strength, and the presence of surface defects of the reinforcing plate. The quality verification step may measure the positional error of the reinforcing plate to verify whether it is within the allowable tolerance. The quality verification step may evaluate whether the bonding strength is greater than or equal to a reference value by measuring it with a tensile testing machine or a torque gauge. The quality verification step may check for surface defects using visual inspection or a magnifying glass.

[0329] According to some embodiments, quality verification may include non-destructive testing, visual inspection, and checking the fastening status of the fastener (104). Quality verification may diagnose internal defects by utilizing non-destructive testing equipment such as ultrasonic testing and infrared thermal imaging. Quality verification can ensure durability during repeated use by checking the fastening torque and loosening status of the fastener (104).

[0330] According to some embodiments, the installation of the lower weight adjustment plate (105) may be a process of attaching a weight adjustment plate (105) to the lower part of the head (100) to adjust the center of gravity. The installation of the lower weight adjustment plate (105) involves inserting the weight adjustment plate (105) into a designated fastening groove on the lower part of the head (100) to adjust the overall center of gravity to suit the user's swing style. The balance and feel of the head (100) may vary depending on the material, thickness, and position of the weight adjustment plate (105). For example, the weight adjustment plate (105) may be made of metal or a composite material and attached parallel to the lower part of the head (100).

[0331] In some embodiments of the present invention, the lower weight adjustment plate (105) has a plurality of fastening grooves and can be installed to allow adjustment of the center of gravity by changing the position of the front and rear. The lower weight adjustment plate (105) can be moved forward or backward according to the position of the fastening grooves to finely adjust the center of gravity. The lower weight adjustment plate (105) can be repeatedly installed and removed at various positions according to the user's requirements. The lower weight adjustment plate (105) can be designed to maintain fastening rigidity even during repeated adjustments by adjusting the tightening strength of the fastening member (104).

[0332] According to some embodiments, the fastener (104) insertion step may be a procedure for inserting a fastener (104), such as a bolt, screw, or pin, to secure the weight adjustment plate (105) to the lower part of the head (100). The fastener (104) insertion step may be performed by aligning the fastener (104) hole of the weight adjustment plate (105) with the fastening groove of the lower part of the head (100) so that they exactly match, and then inserting the fastener (104). The fastening strength and durability of the fastener (104) insertion step may vary depending on the specifications, material, and insertion depth of the fastener (104).

[0333] According to some embodiments, the insertion of the fastener (104) can be performed by aligning the position of the fastening groove with the direction of the weight adjustment plate (105). The insertion of the fastener (104) can be performed by adjusting the front-rear direction of the weight adjustment plate (105) to the user's requirements, and then inserting the fastener (104) into the selected fastening groove to secure it. The insertion of the fastener (104) can be performed by managing the insertion sequence and torque of the fastener (104) so ​​that the weight adjustment plate (105) is secured without shaking.

[0334] In some embodiments of the present invention, the torque management step may be a process of tightening the fastener (104) to a predetermined torque to maintain a constant fastening strength. The torque management step may use a torque wrench to tighten the fastener (104) to a specified torque value (e.g., 1.5 to 3.0 Nm). The torque management step prevents excessive tightening or loosening of the fastener (104), thereby ensuring durability during repeated adjustment of the weight adjustment plate (105).

[0335] According to some embodiments, torque management can ensure durability during repeated adjustments and prevent loosening of the fastener (104). In torque management, an anti-loosening washer or locking nut is applied to the fastener (104) to prevent loosening caused by vibration or shock during use. Torque management can be managed so that the fastening force of the fastener (104) remains constant even after repeated position adjustments.

[0336] According to some embodiments, the position adjustment step may be a procedure for setting the center of gravity by adjusting the front and rear positions of the weight adjustment plate (105) to suit the user's requirements. The position adjustment step may selectively fix the weight adjustment plate (105) to a front or rear fastening groove to move the center of gravity of the head (100) forward or backward. The position adjustment step may customize the center of gravity position according to the user's swing style, body type, and preferences.

[0337] According to some embodiments, position adjustment can be achieved by fixing the weight adjustment plate (105) to a selected position among a plurality of fastening grooves. Position adjustment can be performed by releasing the fastener (104), moving the weight adjustment plate (105) to a desired fastening groove position, and fixing it again. A wear-resistant material may be applied to the position adjustment to minimize wear on the fastener (104) and the fastening groove even with repeated adjustments.

[0338] According to some embodiments, the formation of a waterproof and UV coating layer may be a process of forming a coating layer on the surface of the head (100) that provides waterproof and UV blocking functions. The formation of a waterproof and UV coating layer can prevent discoloration, deterioration, and surface damage caused by moisture penetration and UV exposure to the surface of the head (100). The level of durability and gloss of the waterproof and UV coating layer may vary depending on the type of coating agent, the thickness of application, and the curing method. For example, the waterproof and UV coating layer can be formed by applying various coating agents such as epoxy, lacquer, and polyurethane to achieve protective performance suitable for the usage environment of the head (100).

[0339] According to some embodiments, epoxy or lacquer may be applied to the surface of the head (100) to provide water resistance, weather resistance, and UV protection. The epoxy coating may form a transparent or translucent coating layer, thereby increasing water resistance while maintaining the surface texture and color of the head (100). The lacquer coating may utilize the characteristics of natural materials to ensure both eco-friendliness and durability.

[0340] In some embodiments of the present invention, the choice between epoxy or lacquer may be determined based on the required durability, gloss, and eco-friendliness. For example, an epoxy coating may be applied if a high-gloss finish is required, and lacquer may be selected if eco-friendly certification is required. The application thickness and curing conditions of the epoxy or lacquer may have a direct effect on the final surface quality.

[0341] According to some embodiments, the spraying and coating methods may utilize various techniques such as spray spraying, brush application, and roller application to form a uniform coating layer. The spraying method allows for precise control of the thickness and uniformity of the coating layer using automated equipment during mass production. The brush application method can be applied to small-batch production or to a head (100) with a complex shape to apply the coating agent even to fine parts.

[0342] According to some embodiments, the spraying and coating methods can be optimized according to the shape, surface condition, and production scale of the head (100). For example, a spraying method can be applied to a head (100) with many curved surfaces to minimize variations in the thickness of the coating layer. A roller coating method can be applied to a head (100) with many flat surfaces to increase productivity.

[0343] In some embodiments of the present invention, the curing and polishing step may be a procedure in which the applied coating layer is completely cured to ensure surface durability and gloss. The curing and polishing step may cure the coating layer in various ways, such as natural drying, heat curing, or UV curing. The curing and polishing step may prevent surface defects of the coating layer by precisely controlling the curing time, temperature, and humidity conditions.

[0344] According to some embodiments, curing and polishing can be performed in various ways, such as natural drying, heat curing, and UV curing. For example, the epoxy coating can be naturally dried for 12 to 24 hours at an indoor temperature of 20 to 30°C or heat cured for 2 to 4 hours in an oven at 40 to 60°C. The UV curing method can cure the coating layer within minutes using ultraviolet irradiation equipment.

[0345] According to some embodiments, the additional application of functional reinforcement may be a post-processing step to improve various performance characteristics, such as mechanical strength, durability, environmental stability, and acoustic properties, of the composite head (100). The additional application of functional reinforcement may be carried out as a separate process after the molding of the composite head (100) is completed. The additional application of functional reinforcement may be implemented by applying or inserting reinforcement, additives, or treatment agents onto the surface or interior of the composite head (100). For example, the additional application of functional reinforcement may include steps such as inserting natural fiber reinforcement, inserting glass fiber reinforcement, incorporating weather-resistant additives, applying silane treatment agents, and inserting acoustic property control structures. The additional application of functional reinforcement may change the values ​​of tensile strength, moisture resistance, weather resistance, and acoustic properties of the composite head (100) depending on the type, input location, input amount, and treatment conditions of each reinforcement and additive. The additional application of functional reinforcement may be applied selectively depending on the usage environment, required performance, and manufacturing process of the composite head (100).

[0346] In some embodiments of the present invention, the additional application of functional and reinforcing materials may include steps for applying natural fiber reinforcing materials, glass fibers, weathering additives, silane treatment agents, and acoustic property control structures. The additional application of functional and reinforcing materials may include separate procedures for input, mixing, coating, insertion, curing, and quality inspection for each step. For example, natural fiber reinforcing materials may be input in a certain ratio during the step of mixing coffee grounds powder and synthetic resin. Glass fiber reinforcing materials may be inserted into the interior of the composite head (100) in a layered or mat form. Weathering additives may be uniformly mixed with the synthetic resin to increase resistance to moisture adsorption and temperature changes. Silane treatment agents may be sprayed or coated onto the surface of the composite head (100) to improve surface modification and moisture resistance. Acoustic property control structures may be implemented in various ways, such as internal space design, porous structure, and reinforcing material placement.

[0347] In some embodiments of the present invention, the head (100) may further include natural fiber reinforcement in addition to coffee grounds powder and synthetic resin. The natural fiber reinforcement may be composed of plant fibers such as hemp fiber, flax fiber, and bamboo fiber. The natural fiber reinforcement may be introduced in a certain ratio during the mixing stage of the coffee grounds powder and synthetic resin and may be uniformly dispersed inside the composite head (100). The natural fiber reinforcement may affect the tensile strength, shock absorption capacity, and durability of the composite head (100) depending on the fiber length, diameter, and orientation direction. For example, hemp fiber may be cut into lengths of 5 to 20 mm and mixed with the coffee grounds powder and synthetic resin. The natural fiber reinforcement can improve mechanical strength while minimizing the increase in weight of the composite head (100). The natural fiber reinforcement can simultaneously ensure eco-friendliness and renewableity.

[0348] In some embodiments of the present invention, the head (100) may further include glass fiber reinforcement in addition to coffee grounds powder and synthetic resin. The glass fiber reinforcement may be provided in the form of fine fibers or a mat. The glass fiber reinforcement may be inserted in a layered or dispersed form into the mixture of coffee grounds powder and synthetic resin. The glass fiber reinforcement can significantly improve the tensile strength, bending strength, and impact resistance of the composite head (100). For example, a glass fiber mat may be inserted into the interior of the composite head (100) with a thickness of 1 to 2 mm to increase the rigidity of the entire structure. The glass fiber reinforcement may also contribute to improving moisture resistance and weather resistance.

[0349] According to some embodiments, natural fiber reinforcement or glass fiber reinforcement can reinforce the tensile strength and durability of the composite head (100). The content of natural fiber reinforcement or glass fiber reinforcement can be adjusted to a range of 5 to 20% of the total weight of the composite head (100). Natural fiber reinforcement or glass fiber reinforcement can improve the fatigue durability of the composite head (100) against repeated impacts. For example, a composite head (100) containing natural fiber reinforcement can maintain structural stability without failure in 1,000 repeated impact tests. A composite head (100) containing glass fiber reinforcement can exhibit a fracture load 10% higher than 10% in a three-point bending test.

[0350] According to some embodiments, the head (100) may include a weathering additive to prevent deformation due to moisture and temperature changes. The weathering additive may consist of silicone-based, polyurethane-based, acrylic-based additives, etc. The weathering additive may be mixed with the synthetic resin and uniformly dispersed within the composite head (100). The weathering additive can suppress moisture adsorption and minimize expansion and contraction due to temperature changes. For example, the weathering additive may be added in a range of 2 to 10% of the total weight of the synthetic resin. The application of the weathering additive can prevent warping, cracking, and deformation during long-term use of the composite head (100).

[0351] According to some embodiments, the head (100) may be provided with moisture adsorption and surface modification effects by applying a silane treatment agent together with a weather-resistant additive. The silane treatment agent may consist of a silane coupling agent, a silane-based surface modifier, etc. The silane treatment agent may be applied to the surface of the composite head (100) by spraying, coating, or immersion. The silane treatment agent can improve the interfacial bonding strength between the coffee grounds powder and the synthetic resin, and increase moisture resistance by reducing the hydrophilicity of the surface. For example, the silane treatment agent may be applied to the surface of the composite head (100) with a thickness of 10 to 30 m. The application of the silane treatment agent can simultaneously improve the surface hardness and wear resistance of the composite head (100).

[0352] According to some embodiments, the application of weathering additives and silane treatment agents can improve the moisture resistance, weather resistance, and long-term durability of the composite head (100). The application of weathering additives and silane treatment agents can maintain the weight gain rate of the composite head (100) at 1% or less in a 24-hour moisture absorption test. The application of weathering additives and silane treatment agents can maintain the original shape without structural deformation in a 1000-hour temperature and humidity cycle test. The application of weathering additives and silane treatment agents can ensure long-term durability in a repeated use environment.

[0353] According to some embodiments, the head (100) may include a structure with acoustic properties controlled to reduce impact sound upon striking. The acoustic property control structure can be implemented in various ways, such as the internal space design of the composite head (100), a porous structure, or the placement of reinforcing materials. The acoustic property control structure can control the propagation path and damping characteristics of the shock wave generated upon striking. For example, the impact sound can be dispersed by forming a porous region with a micro-cell structure inside. The acoustic property control structure can control the magnitude and timbre of the striking sound according to the surface thickness of the head (100), the internal partition, and the position of the reinforcing materials.

[0354] In some embodiments of the present invention, the acoustic characteristic control structure can adjust the volume and tone of the striking sound through internal space design, porous structure, and arrangement of reinforcing materials. The internal space design can change the resonance frequency of the impact sound by forming an air layer or a partition inside the head (100). The porous structure can absorb the impact sound by uniformly distributing fine pores with a size of 0.1 to 1 mm. The arrangement of reinforcing materials can tune the tone of the striking sound by adjusting the positions of the reinforcing plate, weight adjustment plate (105), and fiber reinforcing material. For example, adding a partition inside the head (100) can reduce low-frequency impact sound, and expanding the porous structure can reduce high-frequency noise. The acoustic characteristic control structure can customize the volume and tone of the striking sound according to the user's preference.

[0355] According to some embodiments, the park golf club head (100) may have a recyclable structure that can be crushed after use and fed into a remolding process. The park golf club head (100) is composed of coffee grounds powder, synthetic resin, reinforcing material, etc., so that it can be recycled as a raw material in the remolding process even after crushing. The recycling efficiency of the park golf club head (100) can be increased by crushing only the main body after detaching separable parts such as metal fasteners (104), reinforcing plates, and weight adjustment plates (105). For example, the park golf club head (100) can be crushed after use and fed back as a mixed raw material of coffee grounds powder and synthetic resin.

[0356] According to some embodiments, the post-use collection and crushing steps can be applied as essential procedures for eco-friendly resource circulation and waste reduction. The post-use collection and crushing steps can increase the recycling rate of the composite head (100) and reduce environmental pollution caused by landfilling or incineration. The post-use collection and crushing steps can be repeatedly applied within the resource circulation system to ensure environmental sustainability throughout the entire life cycle of the park golf club head (100). For example, the post-use collection and crushing steps can recover more than 1,000 composite heads (100) annually and convert more than 90% into recycled raw materials.

[0357] In some embodiments of the present invention, the cyclic remolding process may include a procedure for repeatedly applying a series of manufacturing steps, such as mixing coffee grounds powder and synthetic resin, molding, curing, and post-processing, using crushed composite head (100) as a raw material. The cyclic remolding process may crush and sieve the particles of the crushed composite head (100) to homogenize them to an average particle size of 50 to 500 micrometers. The cyclic remolding process may control viscosity and mixing uniformity by mixing synthetic resin, a curing agent, additives, etc., with the crushed particles in a certain ratio. The cyclic remolding process may inject the mixed raw material into a metal outer mold and a silicone mold, and remove air bubbles using vacuum injection or a vibrating table. The cyclic remolding process may complete the final product by curing the molded composite head (100) at room temperature or by a heat curing method, followed by demolding and CNC finishing. For example, the circular remolding process can be remolded by mixing 1 kg of crushed composite head (100) with 0.3 kg of epoxy resin, 0.03 kg of curing agent, and 0.02 kg of additive.

[0358] In some embodiments of the present invention, the circulating remolding process can ensure the quality of the recycled raw material by managing the particle size, moisture content, and mixing uniformity of the crushed composite head (100). The circulating remolding process can maintain consistency in molding quality by homogenizing the particle size distribution of the crushed particles to a relative standard deviation of 10% or less. The circulating remolding process can improve adhesion to the synthetic resin and curing quality by drying the moisture content of the crushed particles to 1% or less. The circulating remolding process can achieve uniform mixing of the raw material by controlling the stirring speed, time, temperature, etc., during the mixing step. For example, the circulating remolding process can mix the crushed particles by drying them at 120°C for 2 hours and then stirring at 200 rpm for 30 minutes.

[0359] According to some embodiments, the circular remolding process can be designed so that mechanical strength, durability, and surface quality are maintained even after repeated recycling. To prevent degradation of the quality of the recycled raw material, the circular remolding process may add additives, reinforcing materials, surface treatment agents, etc. The circular remolding process can verify whether key physical properties, such as tensile strength, shock absorption capacity, and surface roughness, meet design criteria even after repeated recycling. For example, the circular remolding process can maintain a tensile strength of 28 MPa or more and a surface roughness of 0.1 micrometer or less even after three repeated recyclings.

[0360] Although the embodiments have been described above with reference to the limited drawings, those skilled in the art can apply various technical modifications and variations based thereon. For example, suitable results may be achieved even if the described techniques are performed in a different order than described, and / or if the components of the described system, structure, device, circuit, etc. are combined or assembled in a form different from described, or replaced or substituted by other components or equivalents.

[0361] Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the claims set forth below.

Claims

Claim 1 A park golf club comprising: a head molded from a composite material including coffee grounds powder and synthetic resin; and a shaft coupled to the head, wherein the coffee grounds powder has an average particle diameter in the range of 50 to 500 micrometers and is uniformized with a relative standard deviation of particle size distribution of 10% or less, a reinforcing plate formed of a carbon fiber plate with a thickness of 6 to 8 mm is attached to the front surface of the head using epoxy adhesive and fasteners to reinforce shock absorption and rebound force, and a weight adjustment plate is attached to the lower surface of the head having a plurality of fastening grooves to adjust the center of gravity so that the front and rear positions can be changed. Claim 2 A park golf club according to claim 1, wherein the head has a porous structure so that internal pores improve shock dispersion and rebound force. Claim 3 delete Claim 4 delete Claim 5 A park golf club according to claim 1, wherein the head includes a shaft coupling portion for coupling the shaft, and the angle of inclination of the shaft coupling portion relative to the ground is adjustable to suit the user's body type.

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