Abstract:
A golf club head having a body that includes a striking wall, an upper wall, and an open cavity. A housing is positioned within the cavity and it is removably attached in such position to the body. The housing has an asymmetrical configuration and is located in the open cavity of the body in a predetermined selected position and is removably connected to the body in the predetermined position. At least one balancing weight is located with respect to the housing in a predetermined selected position, the weight being non-removably connected to the housing by adhesive or by being molded in place, for example. A plurality of identically shaped housings, with differently positioned weights, can be provided to enable one to select a desired one of the housings to be fitted to the body of the club head to appropriately modify the behavior of the thusly assembled club.

Description:
FIELD OF THE INVENTION 
     The present invention relates to the field of golf clubs. 
     The invention is more particularly related to a golf club head which includes, in particular, a detachable assembly of a recessed body and a housing. 
     DESCRIPTION OF BACKGROUND AND RELEVANT INFORMATION 
     Conventionally, each club of a series has a precise and defined geometry, such that a player can select a suitable club from the series, depending upon the conditions of the game. 
     However, for a given geometry, a player can be led to adjust the mechanical characteristics of his or her club, in order to improve its performance. 
     It is known that the distribution of the mass in the golf club head, within a volume defined by said head, has a considerable influence on the behavior of the club striking during a ball striking motion, commonly referred to as the swing. 
     Therefore, the prior art has proposed devices to enable a player to modify the distribution of mass in a golf club head. 
     In particular, the document U.S. Pat. No. 4,695,054 describes a golf club head which comprises especially a detachable block bored with two blind holes in which selected weights can be positioned. After the positioning of the weights, the block is fixed in a cavity of the head. The assembly obtained is a golf club head for which the position of the center of gravity contributes to attenuate, at least partially, the deficiencies due to the imperfect execution of the swing by the player. 
     A first drawback of such a structure is its complexity. It renders the necessary manipulations for the mounting and dismounting of the weights difficult. 
     In addition, these manipulations are time-consuming and tedious. 
     Another drawback originates from the structure of the block which can be mounted in the head in two different manners: a mounting error can lead a player to position the weights such that its swing deficiencies are accentuated, instead of being attenuated. 
     Another drawback is that the differences in the distribution of masses between the possible adjustments are very small, because the geometrical center of the head is located in the vicinity of the center of mass. 
     The document U.S. Pat. No. 4,630,825 describes a golf club head defining cavity closed by a removable plug. The plug is located along the length and at the lower portion of the head. The plug serves as a mass and can be made of various materials. A head according to this document allows neither a mass distribution that enlarges the size of the effective zone upon the impact of a ball on the head, nor an improvement to the lift of a ball on its trajectory. 
     SUMMARY OF THE INVENTION 
     In order to remedy these drawbacks, the golf club head according to the invention includes, on the one hand, at least one body comprising walls, in particular, including a striking wall and an upper wall, in which body an open cavity is provided, and includes, on the other hand, a housing to be nested and removably fixed in the cavity of the body and at least partially filling the cavity, the housing comprising at least one balancing weight, the weight being irremovably fixed with respect to the housing in a selected position, wherein the housing is asymmetrical and wherein the shape of the cavity is similar to that of the housing, so as to allow for only one mounting position of the housing in the cavity. 
     The complex manipulations imposed by the prior art in positioning the weights are eliminated: it suffices to replace a housing balanced in a certain manner by another housing balanced in a different manner. 
     The replacement is all the more easier because the housing is asymmetrical and the shape of the cavity is similar to that of the housing, so as to allow for only one position for mounting the housing in the cavity. 
     Without leaving the scope of the invention, one can provide to form an assembly comprising a golf club head and at least two housings, the head comprising a body in which an open cavity is provided, and each housing being asymmetrical and filling the cavity whose shape is similar to that of the housing, the assembly being such that the housings have the same shape and a different mass, only one of the housings being assembled with the head. 
     This assembly enables the player to select the housing that is best suited to adjust his or her trajectories by controlling the quality of the impact of a ball on the club head. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other characteristics and advantages of the invention will become apparent from the description that follows, with reference to the annexed drawings, and in which: 
     FIG. 1 is a perspective view of a conventional head; 
     FIG. 2 is a perspective view of a head similar to that of FIG. 1, but from another angle; 
     FIG. 3 is a perspective view of a recessed head; 
     FIG. 4 is a perspective view of a recessed head, which is different from FIG. 3; 
     FIG. 5 is a perspective view of the assembly of a housing with a head similar to that of FIG. 3 or of FIG. 4; 
     FIG. 6 shows that a housing comprising a ridge can be mounted on a head provided with an arch to partially or totally fill the cavity; 
     FIG. 7 is a perspective view of the assembly of a housing comprising a ridge with a head provided with an arch; 
     FIG. 8 is a cross-section along the line VIII—VIII of FIG. 7; 
     FIG. 9 is a cross-section along the line IX—IX of FIG. 7; 
     FIG. 10 is a cross-section along the line X—X of FIG. 7; 
     FIG. 11 is an external view of a housing according to a preferred embodiment; 
     FIG. 12 is a cross-section along the line XII—XII of FIG. 11, showing cavities of the housing prior to their filling; 
     FIG. 13 is similar to FIG. 12, but shows cavities of the housing after their filling; 
     FIG. 14 is a partial enlargement of FIG. 8; 
     FIG. 15 schematically shows a possible architecture to define cavities in a housing; 
     FIG. 16 shows another arrangement of the cavities; 
     FIG. 17 is a cross-section of the housing defining a single cavity partially filled with a mass; 
     FIG. 18 is equivalent to FIG. 17; 
     FIG. 19 gives an example of an assembly constituted by one head and a plurality of housings having an identical shape and a different positioning of the weights. 
     FIG. 20 is a perspective view of a recessed head according to an alternative embodiment; and 
     FIG. 21 is a view of a head similar to that of FIG. 20, on which a housing is connected. 
    
    
     DETAILED DESCRIPTION 
     FIG. 1 shows a head  1  affixed to one end of shaft  2 , especially provided with a striking wall  3  and a top or upper wall  4 . 
     The head  1  is also shown in FIG. 2, from a different angle, and show a wall  5  beneath the head, referred to as a lower wall or sole, as well as a lateral wall  6 , a rear wall  7  and another lateral wall  8 . 
     All of the walls  3 ,  4 ,  5 ,  6 ,  7  and  8  form the body of the head  1 . 
     FIG. 3 shows an example of cavity  9  obtained by successively cutting out the lower  5 , lateral  6 , rear  7  and lateral  8  walls. A recess defines the cavity  9  which, in this non-limiting example, has the particularity of extending deeply within the body of head  1 . The cavity  9  whose peripheral edge  10  preferably has a constant thickness, can even be provided such that each of the walls  3 ,  4 ,  5 ,  6 ,  7  and  8 , is fairly thin. 
     In a preferred embodiment, the average thickness of the walls  4 ,  5 ,  6 ,  7  and  8  will be on the order of 2 mm, and the thickness of the striking wall  3  will be comprised between 2 and 6 mm; these values being non-limiting for a head made of metal or composite material, for example. 
     As shown in FIG. 4, the cavity  9  obtained after the recess is made can be substantially less deep than that of FIG. 3, and it can, for example, be at least partially demarcated by at least one wall, such as walls  11  and  12 . 
     An example of embodiment of the head  1  according to FIG. 4 consists of filling a portion of the cavity  9 , obtained as indicated and shown in FIG. 3, with a material such as a polyurethane foam. In this case, the walls  11  and  12  are made of foam. 
     Another example of embodiment of the head  1  whose cavity  9  is demarcated at least partially by walls, consists of attaching these walls on the peripheral edge  10  by any means such as adhesion, welding or the like. 
     Regardless of the volume of the cavity  9 , and regardless of the material used and their arrangement, the golf club head  1  comprises at least two detachable elements, a body in which a cavity  9  is provided which communicates with the outside of the body through at least one opening  14  demarcated by the peripheral edge  10 , and a housing  13  filling the cavity  9  at least partially, the body comprising especially walls, including a striking wall  3  and an upper wall  4 , and the housing  13  comprising at least one balancing weight, which is particular in that the weight is irremovably fixed with respect to the housing  13  in a selected position. 
     FIG. 5 shows the housing  13 , positioned in the cavity  9  of the head  1  such as shown in FIG. 3 or in FIG.  4 . The housing  13  takes support either on at least one peripheral portion  10  of the peripheral edge of the cavity  9 , or on at least one portion of the surface of walls  11  and  12 . 
     The shape of the housing  13  provides the assembly of the recessed body of the head  1  and of the housing  13  with an aspect similar to that of a conventional golf club head shown in FIGS. 1 and 2. 
     The housing  13  is maintained on the remainder of the head  1  by any means, known to the one skilled in the art, that enables a disassembling of the assembly of the housing  13  and of the head  1 . 
     According to a preferred embodiment, there exists only one position for the detachable assembly of the housing  13  on the head  1 . In this regard, the housing  13  is asymmetrical and the shape of the cavity  9  is complementary to that of the housing  13 , so as to allow for only one position for mounting the housing  13  in the cavity  9 . 
     Preferably, the cavity  9  is formed in the rear lower portion of the head, by means of cutouts of the lower wall  5  or sole, as well as of the lateral walls  6  and  8  and of the rear wall  7 . This localization has been shown in FIGS. 3,  4  and  5 , but it is also visible in FIGS. 6,  7 ,  8 ,  9 ,  10 ,  14  and  19 . 
     Indeed, it is very advantageous to distribute the mass of a golf head in certain zones, and especially on the sides or toward the rear of the head. 
     Masses positioned on the sides, in the vicinity of the lateral walls  6  and  8  make it possible to enlarge the size of the effective zone upon impact of a ball on the head  1 , which is generally referred to as the sweet spot. 
     Masses positioned at the rear, in the vicinity of the wall  7 , cause an increase in the inclination of the striking surface  3  during the swing. This phenomenon related to the centrifugal force, and referred to as the dynamic loft, improves the lift of a ball on its trajectory. 
     The housing  13  according to the invention will thus make it possible to remove or return masses in the head  1 , in a precise and selected area. 
     According to the preferred mode of construction shown in FIG. 6, a head  1  and a housing  13  have complementary forms and are design to nest with one another by means of a manipulation imposed by the structure of the assembly. The housing  13  comprises a ridge  15  projecting on one of its surfaces, on the one hand, and the opening  14  is partially closed by an arch  16  which connects a front portion  17  of the sole  5  to the rear wall  7 , on the other hand, such that the ridge  15  is in contact with the arch  16  after the mounting of the housing  13  in the cavity  9 . 
     The arrows of FIG. 6 show that a housing  13  can be selectively mounted in a cavity  9  partially demarcated by the walls  11  and  12 , or can be mounted by taking support on at least one peripheral edge  10  of a cavity  9  cut deeply into the head  1 . 
     In each case, the ridge  15  of the housing  13  comes in abutment against a flank  18  of the arch  16 . This arch  16  divides the peripheral edge  10  of the cavity  9  into two portions, to define two inlets  19  and  20  in this cavity  9 . 
     The assembly thus constituted has the advantage of being rigid, and of allowing an easy and rapid positioning or removal of the housing  13  with respect to the head  1 . 
     As will be seen hereinafter, a hole  21  in the arch  16  allows for passage of a screw  22 , a rivet or any other detachable means. 
     FIG. 7 shows an assembly of a head  1  with a housing  13  according to a preferred and non-limiting embodiment. The screw  22  is fixed in the housing  13  through the hole  21  of the arch  16 . This arrangement prevents any relative displacement of the head  1  and of the housing  13 . 
     The cross-section along VIII—VIII shown in FIG. 8, along a substantially median plane of the head  1  and passing approximately in the middle of the arch  16 , shows by way a non-limiting example, the arrangement of a weight  23  in the housing  13  at the rear of the head  1 . The weight  23  is fixed in a cavity of the housing  13  via a means which will be described subsequently. Preferably, the housing  13  is in contact with the arch  16  along a contact surface  24 . The screw  22  maintains the housing  13  in a fixed position. In this example, the cavity  9  is filled only partially by the housing  13 . 
     As shown in FIGS. 9 and 10, the housing  13 , according to the same non-limiting example of FIG. 8, is in support especially on the peripheral edge(s)  10 . A very precise positioning is advantageously obtained by contact of the ridge  15  of the housing  13  on the arch  16  of the head  1 . 
     A complementary function of the intersection of the ridge  15  with the arch  16  is to allow for only one direction for mounting or dismounting the housing  13  with respect to the head  1 . 
     A complementary function of the arch  16  is to absorb the possible shocks during the swing and to protect the housing  13 . 
     This housing  13  can be made out of any material, such as metal, plastic, wood or other materials. However, it is preferably made of a low density material, such as aluminum, plastic or a low density resin. 
     One or more weights are arranged in this housing  13  in selected areas. An example of arrangement is proposed in FIG. 11, where the housing  13  is seen from the side of the ridge  15  with three weights  23 ,  25 ,  26 , inserted in three cavities shown in dotted lines, and a hole  27  for receiving the screw  22 . 
     Various m o des are possible for affixing a weight on or in a housing  13 . 
     For example, a weight can be fixed to the housing  13  by means of a layer having adhesive properties. This is the known adhesion technique. 
     Possibly, a melted metal can be cast directly in a cavity of the housing  13 . 
     For example, the lead used as a mass assumes the forms of a housing  13  made of epoxy resin, and possibly enables an undercut molding. 
     Regardless of the process, each weight can be confined in a closed cavity of the housing  13 . It suffices that the weight be embedded in the constituent material of the housing  13 . 
     FIGS. 12 and 13 are cross-sections of the housing  13  according to a non-limiting example. Two lateral cavities  28  and  29  of the housing  13  have been filled by two lateral masses or weights  25  and  26 . These weights adhere to the walls of the cavities  28  and  29  as has been explained previously. 
     FIG. 14 is a partial enlargement of FIG. 8 which shows a rear weight  23  and the immobilization of the housing  13  by means of a screw  22  with a countersunk head  30 . This countersunk head  30  makes it possible to obtain a good tightening because its conical shape becomes easily stuck on the walls  31  of the hole  21  of the arch  16 . 
     Now, independently of techniques for fixing the weight(s) with respect to the housing  13 , various structures help in selecting zones or cavities for receiving these weights. The goal is to obtain a housing  13  that is specifically balanced and whose center of gravity is selectively positioned with respect to the geometrical center. Since the housing is then mounted in a precise and unique manner in the head  1 , the latter will in turn have a center of mass selectively positioned with respect to its geometrical center. The choice of a housing  13  for assembly in the head  1  is interesting because it enables a player to modify characteristics for balancing masses in the head of his or her club, without influencing the other characteristics. 
     The player advantageously modifies his or her ball trajectories by only changing the housing  13 ; this adjustment system allows for better sensations. 
     This solution has a major psychological advantage because the golf player maintains an equipment to which he is accustomed. 
     This solution also has an economical benefit, because the price of a housing is substantially lower than that of a head or of a club. 
     A few examples of housing structures are shown in succession in FIGS. 15,  16 ,  16 ,  17 , and  18 . 
     FIG. 15 proposes a plurality of cavities  32  defined in the housing  13  to form at least one receiving cell for a weight. 
     The advantage is that it suffices to select those of the cavities  32  that one desires to weigh down. Another advantage is the ease with which series of housings with selected characteristics are produced. 
     FIG. 16 proposes a simplified architecture that has the advantage of being very economical: three blind holes serve as receiving cavities  32  for masses. Each cavity of the housing is made at a selected location for positioning a weight which, preferably, fills this cavity integrally . 
     Another configuration proposes a single cavity  33  in a housing  13 , as shown in FIGS. 17 and 18. 
     A mass  34  is fixed in a selected zone of the cavity  33 . This is, for example, melted lead, reinforced resin, or any material. 
     Advantages of this configuration are essentially its extreme simplicity and the ease of implementation thereof: the single cavity is partially filled by a weight  34 . 
     One can provide to fill the volume of the cavity  33  that is not filled by the weight  34 , by a low density plastic material such as a polyurethane foam. 
     By low density is meant a density less than 1 kg/dm 3 . 
     It is possible to imagine an infinite number of alternative embodiments. A common point to all these alternative embodiments is the possibility of placing a seal at least partially in contact with both the housing and the head. This seal is preferably a silicone-based paste, for example, and extends along the peripheral edge  10  of each opening  14  or inlet  19 ,  20  of the head  1 . 
     This seal ensures sealing functions if the portion of the cavity  9  that is not occupied by the housing is neither filled with a material such as foam, nor separated from the housing by walls. 
     The advantage is that foreign bodies, such as water or dust, cannot fill this space in the cavity  9 . 
     Furthermore, the seal advantageously plays the role of absorbing the vibrations that propagate in the head  1  during the impact of a ball on the striking surface  3 . 
     Finally, a major interest in the invention resides in the possibility of constituting an assembly comprising a single head  1  and at least two housings  13 , all of the housings having an identical shape and a different localization for their center of mass, only one of the housings being assembled with the head. 
     An example of an assembly of a head  1  and of six different housings  13  is provided in FIG.  19 . 
     Advantageously, a player can change a housing  13 , thereby changing the behavior of his or her club, to compensate for the imperfections in the swing. 
     His or her performance will therefore be improved. 
     The mass of a head  1  associated with a housing  13  will, for example, be on the order of 200 g, the body of the head  1  substantially weighing 140 g and the housing  13  weighing 60 g. However, the mass of the weight(s) inserted in the housing will preferably be close to 50. 
     These weight values offer a host of adjustment possibilities. 
     Of course, the invention is not limited to the embodiments thus described, and comprises all of the technical equivalents that fall within the scope of the following claims. 
     In particular, one can imagine a golf head similar to that shown in FIGS. 20-21. 
     The head  1  is recessed so as to essentially maintain the most functional portions including, in particular, the striking wall  3 , the upper wall  4 , the end of the shaft  2 , and a tongue  35  which plays the role of the sole  5 . 
     A curved edge  36  of the upper wall  4  is adapted to receive a housing  37  whose shape is similar to that of a crescent and substantially complementary to the curved edge  36 . The housing  37  does not completely fill an open cavity  38  demarcated by the striking surface  3 , the upper wall  4  and the tongue  35 . In accordance with the spirit of the invention, the housing  37  is removably maintained on the curved edge  36  and makes it possible to distribute the masses on the sides and to the rear of the head  1 . The housing  37  can comprise masses, as previously described. The housing  37  can also be a piece made of a single material whose cross section varies along the curved edge  36 .