Abstract:
An integrally formed golf club comprising: a golf club head and a golf shaft, wherein the golf club head including a club head component formed by casting, the casted club head component has a club head surface formed by forging, the golf shaft is formed by drawing the casted club head component, and is integrally formed with the casted club head component. It thus the integrally formed golf club has characteristics of excellent distributed strength and no partial concentration of applied force, it thus the accuracy of direction and the ability of control is improved.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a golf club, and more particularly, to an integrally formed golf club. 
       BACKGROUND OF THE INVENTION 
       [0002]    Golf is a kind of attractive exercise because of its beautifully evergreen golf course, which makes people feel just like wandering in nature. This gentle exercise, golf, makes people feel relaxed, and it is the best exercise for friends social. Golf clubs are classified and labeled with specified numbers for a golfer to choose from them depending on different situations including gradient and wind direction. Golf clubs are classified as driver golf clubs, iron golf clubs, and putter golf clubs. The driver club, which is used for tee-off, usually has a big head and is weighted, so it is usually difficult for a golfer to control not only in distance but in direction. Moreover, the iron clubs, each having specific loft angle, are used for grounding on a green, which need more control in direction than in distance. The putter clubs are specifically designed in its weight steadiness in order for a golfer to putter the golf ball in the hole on a green. 
         [0003]    In general, each golf club comprises a golf shaft and a golf club head, wherein the golf club head is generally made of stainless steel, metal alloy, or composite material by processes of casting or injection molding. The material of golf shaft includes carbon fiber and metal alloy. All of the above golf clubs are manufactured by fitting the golf shaft to the club head and gluing on the connected portion. The strength, hardness and toughness for golf club heads made of wood, carbon fiber, metal alloy through process of hot-pressing or injection molding are comparatively weak as compared with the golf club heads having the same thickness but made of metal alloy or stainless steel. 
       SUMMARY OF THE INVENTION 
       [0004]    In order to increase the joining strength of the club head as being fitted with the golf shaft, the connecting portion of the club head is made as stretching and tapering upwardly as a cone. The fitting hole located within the center of the connecting portion is made deeper as being located below the surface of the club head. In consideration of the strength and the hardness of the connecting portion being weak, the connecting portion between the golf club head and the golf shaft are wrapped by a synthetic thread in order to increase the joining strength. 
         [0005]    However, the joining strength between the golf club head and the golf shaft is determined in accordance with joining strength of the connecting portion between. The different materials of the golf club head, the golf shaft and the synthetic thread are chosen to determine the hardness of elements really used. The connecting portion between the golf club head and the golf shaft are connected with different applied forces, so some partial areas of the connecting portion are loaded with a force of over-stress concentration. Thus, when the golf club head is contact with a golf ball, the connection portion is easily deformed, or even is fractured. As known from the above, the impact force applies to the golf club head while a golf ball is hit, and is transferred as a torsion force to the golf shaft. That torsion force will generate a torsion angle between the golf shaft and the golf club head to affect the ball accuracy of flight direction. Moreover, if the torsion force is too huge, the tight connection between the golf club head and golf shaft becomes loosened, and the damage of golf club will happen. 
         [0006]    Therefore, the purpose of the present invention is provided an integrally formed golf club that eliminates the drawbacks of the aforesaid prior art golf club. 
         [0007]    Therefore, the present invention provides an integrally formed golf club comprising a golf club head and a golf shaft, wherein the golf club head including a club head component formed by casting, the casted club head component having a club head surface formed by forging, the golf shaft is formed by drawing the casted club head component and is integrally formed with the casted club head component. 
         [0008]    According to an embodiment of the present invention, a drawn portion is integrally formed between the golf club head and the golf shaft to form a junctionless structure. 
         [0009]    According to an embodiment of the present invention, the outer surface of the drawn portion is smooth without roughness. 
         [0010]    According to an embodiment of the present invention, the club head component of the golf club head has a club head hollow portion, and the golf shaft has a shaft hollow portion. 
         [0011]    According to an embodiment of the present invention, the club head hollow portion of the golf club head and the shaft hollow portion of the golf shaft are integrated formed with each other. 
         [0012]    According to an embodiment of the present invention, the club head component of the golf club head has a club head hollow portion, and the golf shaft has a shaft solid portion. 
         [0013]    According to an embodiment of the present invention, the golf club head has a club head surface whose roughness is different from that of the golf shaft surface. 
         [0014]    According to an embodiment of the present invention, the golf shaft is integrated formed with the golf club head by means of plangage butted drawing, single butted drawing, double butted drawing, buldge butted drawing, or contracted butted drawing. 
         [0015]    According to an embodiment of the present invention, the golf club head and the golf shaft are made of a dual phase steel metal. 
         [0016]    By means of technical means applied by the present invention, the golf club head and the golf shaft are integrally formed by processes of casting, forging, and then drawing, so the integrally formed golf club has characteristic of excellent distributed strength. Therefore, the joining strength between the golf club head and the golf shaft is greater than the conventional glued jointing structure. The integrally formed golf club of the present invention overcomes the drawbacks of partial concentration of applied force and prevents from being loosened in the joint portion that usually happen in the conventional golf club. Therefore, the torsion force applied in the golf club is uniformed contributed, and the life duration of the golf club is extended. 
         [0017]    The integrally formed golf club of the present invention has not any joint portion. It thus uniformed distributes the torsion force in the whole golf club including the golf club head and the golf shaft, but not partially concentrates in the connecting portion, i.e., the joint portion, as happened in the prior art. Moreover, since the torsion angle generated in the golf club of the present invention is much less than the conventional glue connected golf club, the accuracy of direction and the ability of control is improved in the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings as follow. 
           [0019]      FIG. 1  is a stereogram illustrating an integrally formed golf club of the first embodiment according to the present invention; 
           [0020]      FIG. 2  is a partial schematic diagram illustrating an integrally formed golf club of the first embodiment according to the present invention; 
           [0021]      FIG. 3  is a partial cross section diagram illustrating an integrally formed golf club of the first embodiment according to the present invention; and 
           [0022]      FIG. 4  is a partial cross section diagram illustrating an integrally formed golf club of the second embodiment according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0023]    Please refer to  FIGS. 1-4 .  FIG. 1  is a stereogram illustrating an integrally formed golf club according to the first embodiment of the present invention.  FIG. 2  is a partial schematic diagram illustrating an integrally formed golf club of the first embodiment according to the present invention.  FIG. 3  is a partial cross section diagram illustrating an integrally formed golf club of the first embodiment according to the present invention.  FIG. 4  is a partial cross section diagram illustrating an integrally formed golf club of the second embodiment according to the present invention. 
         [0024]    As shown in  FIGS. 1-3 , an integrally formed golf club  100  of the present invention includes a golf club head  1  and a golf shaft  2 . The golf club head  1  includes a club head component  11  formed by casting, and the casted club head component  11  has a club head surface  111  formed by forging. In this embodiment, the club head surface  111  is formed by treating the casted club head component  11  in a forging process. The golf shaft  2  is formed by drawing the casted club head component  11 , it thus the golf shaft  2  is provided with a shaft component  21  integrally formed with the golf club head  1 . And a grip  211  is provided on the end of the shaft component  21 . 
         [0025]    A drawn portion  3  is provided between the golf club head  1  and the golf shaft  2 , and the outer surface of the drawn portion  3  is a smooth surface without roughness. In this embodiment, the smooth surface is a junctionless smooth surface. In other words, a drawn portion is integrally formed between the golf club head and the golf shaft to form a junctionless structure. The outer surface of the golf shaft  2  is rougher than the outer surface, such as a club head surface  111 , of the golf club head  1 . In other embodiment, the outer surface of the golf club head and the golf shaft is smooth without roughness. In this case, a separate shaft is covered on the golf shaft. The club head surface  111  is used as a contact surface for hitting a golf ball. In this embodiment, the club head component  11  of the golf club head  1  has a club head hollow part  12 , and the shaft component  21  of the golf shaft  2  has a shaft hollow part  22 . The club head hollow part  12  of the golf club head  1  and the shaft hollow part  22  of the golf shaft  2  are hollow integrated with each other. 
         [0026]    In this embodiment, the processes of drawing are described as follows: a blank of the golf shaft  2 , which is used for drawing, is connected with the casted forged golf club head  1 ; a golf shaft  2  with a shaft hollow part  22  is formed by drawing the blank of the golf shaft  2  to make the blank of the golf shaft  2  pass through a drawing mold and a mandrel located in the center of the drawing mold. 
         [0027]    In this embodiment, a weight member  13  is provided within the club head hollow part  12  during the manufacturing process, and the weight member  13  is positioned and closely fixed within the club head component  11 . 
         [0028]    As shown in  FIG. 4 , in the second embodiment, it discloses an integrally formed golf club  100   a  with different specifications and requirement. The manufacturing process of the integrally formed golf club  100   a  is similar with the manufacturing process of the integrally formed golf club  100 . The integrally formed golf club  100   a  of the second embodiment is different from the integrally formed golf club  100  of the first embodiment in follows. The shaft component  21   a  of the golf shaft  2   a  is provided with a shaft solid portion  22   a.  Specifically, during the process of drawing the golf shaft  2   a,  the blank of the golf shaft  2   a  passes through a drawing mold to form the shaft hollow part  22   a  of the golf shaft  2   a.  However, the manufacturing process of the integrally formed golf club  100   a  is similar with the manufacturing process of the integrally formed golf club  100 . 
         [0029]    In the manufacturing process of integrally forming the integrally formed golf club  100 ,  100   a,  the club head component and the shaft component are formed by following processes: casting, forging, and then drawing in sequence. The golf head and the shaft are casted to be original objects, and then the club head surface of the golf head is forged. Then the golf head and the shaft are processed by drawing to be integrally formed. Depending on the shape and the size of the integrally formed golf club, the drawing process can be classified into plangage butted (PG) drawing process, single butted (SB) drawing process, double butted (DB) drawing process, buldge butted (BB) drawing process, and contracted butted (CB) drawing process. 
         [0030]    The drawing processes are different according to various sizes, shapes, and appearances of the integrally formed golf club  100 ,  100   a.  For example, it only requires one step to finish drawing for the integrally formed golf club if there is only size for the outer diameter and thickness of the golf shaft, and then the plangage butted drawing process is suitable for this. In the case that the integrally formed golf club is one size in the outer diameter but has two sizes in its thickness (in general, the thickness is not uniform), the single butted drawing process is applied then. During the process of drawing, there are two processes required, including a process of “thickness formation” and a process of “outer diameter molding”. In other words, during the process of drawing, the thickness of the golf shaft is firstly processed, and then outer diameter of the golf shaft is processed, during which the double butted drawing process is suitably applied. During the process of drawing, since the mandrels are different from the front end to the back portion, the diameter of the golf shaft is thus enlarged when the processing material is reversed, so the buldge butted drawing process is suitable applied. And in the case that the integrally formed golf club is made with the outer diameter of the golf shaft being partially reduced and the thickness being with one size, the contracted butted drawing process is suitable applied. 
         [0031]    Furthermore, in the present invention, the club head component and the shaft component of the integrally formed golf club  100 ,  100   a  can be made of Duplex Stainless Steel (DSS) such as stainless steel grades 2205, that contains 22% of Chromium (Cr) and 5% of Nickel (Ni). The Duplex Stainless Steel has the advantages of high strength, excellent corrosion resistance, so it is suitable for manufacturing the integrally formed golf club  100 ,  100   a.  The integrally formed golf club  100 ,  100   a  can be made of other metal, such as stainless steel, chrome molybdenum steel, chrome-plated carbon steel, and so on, and these are only a preferred embodiment but not limited. 
         [0032]    The above description should be considered as only the discussion of the preferred embodiments of the present invention. However, a person skilled in the art may make various modifications to the present invention. Those modifications still fall within the spirit and scope defined by the appended claims.