Abstract:
A golf club head is disclosed that comprises a body having a striking face, a rear cavity and a sole bar, wherein a recess is formed in the sole bar that extends generally from the rear cavity. An insert is located within the sole recess, the insert including a core and an intermediate layer that separates the core from the recess wall. The intermediate layer has a hardness and a modulus of elasticity that are less than that of the core, such that when the golf club head is used to strike a golf ball, the resulting vibrations are dissipated by compression of the intermediate layer and movement of the core with respect to the intermediate layer.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]    This is a continuation-in-part of co-pending application Ser. No. 09/728,955, filed Dec. 1, 2000. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates generally to the golf clubs and, more particularly, to golf club heads.  
           [0003]    Modern golf clubs have typically been classified as either woods, irons or putters. The term “wood” is a historical term that is still commonly used, even for golf clubs that are constructed of steel, titanium, fiberglass or other more exotic materials, to name a few. The term “iron” is also a historical term that is still commonly used, even though those clubs are not typically constructed of iron, but are rather constructed of many of the same materials used to construct “woods”.  
           [0004]    Many advancements have been achieved, particularly over the past couple of decades, to make it easier to hit longer and straighter shots with woods and irons. In general, golf clubs are now designed to be more forgiving, so that shots that are struck less than perfectly will still have fairly consistent distance and directional control. Moreover, club heads now commonly are constructed of combinations of materials, to attempt to optimize the ball flight desired by a particular type of player.  
           [0005]    One particular improvement that relates to irons is the use of perimeter weighting, whereby a disproportionate amount of the total weight of a club head is positioned behind and proximate the perimeter of the club head&#39;s striking face, thereby creating a cavity immediately behind the striking face. The cavity is formed by the club face wall and the weight that is placed around and behind the club face. This type of club is typically referred to as a “cavity back” iron. By moving the weight peripherally away from the center of gravity (CG) of the club head, the club is made to be more forgiving on off-center hits, resulting in more consistent distance and directional control. Further, perimeter weighting generally increases the moment of inertia about the club&#39;s CG, resulting in less twisting due to off-center hits, and more accurate shots.  
           [0006]    There are so-called “hollow” irons that incorporate a rear wall that is spaced from the front striking face. This also increases the moment of inertia about the club&#39;s CG and is found to benefit some higher handicap golfers. Some hollow irons more closely resemble fairway woods in cross-sectional shape, while other hollow irons may resemble cavity back irons in their cross-section.  
           [0007]    Another improvement is the use of lighter and stronger materials, which enables club designers to move the CG to an optimal location on a wood or iron. Such a movement can make the club either easier to hook or to fade, if the movement is made either closer to or farther from the hosel. Similarly, if the CG is moved higher or lower with respect to the club face, the golf ball launch conditions can be altered. For instance, lowering the CG generally makes it easier to get the ball airborne for either an iron or a wood. Conversely, raising the CG promotes a more boring ball flight that generally leaves the club face at a lower launch angle.  
           [0008]    Generally, it has been shown that it can be advantageous for players with higher handicaps to use clubs with a lower CG. This is especially true for long irons, such as for example a  3 -iron. Club designers have responded to this prospective advantage by lowering the CG of both woods and irons for clubs intended for higher handicap players. The most common way that this has been accomplished for irons is to move as much weight as possible to the area proximate the sole of the club. This results in a concentration of weight proximate the sole. Often, for these types of irons, the transition from the cavity to the weight on the sole is abrupt, compared to traditional irons having a smoother transition. When viewing a cross-section of the lower portion of the club face, a dramatic change in the thickness of the face nearer the sole often is apparent in such sole-weighted club heads.  
           [0009]    While it is recognized that the lower CG of the improved clubs can be beneficial, such a lowering can have negative side effects. First, the concentrated mass proximate the sole can increase the stiffness of the club head. This can cause a noticeable change in the club&#39;s feel. Feel is a term that is generally used by skilled practitioners to denote a subjective expression of the way a club feels to one&#39;s hands when striking a golf ball, or the way it sounds. Feel is generally perceived as audible to tactile feedback to the golfer. Different sensations due to striking the ball in different locations on the club face may make a club less desirable to a potential user.  
           [0010]    Second, the weight concentration proximate the sole can lead to different levels of flex at different points on the club face. The area of the face proximate the thickest portion of the sole is likely to flex less than the area proximate the inner areas of the striking face. Such a change in flex can adversely affect performance.  
           [0011]    Third, the weight concentration can lead to excess vibration, which can adversely affect the feel of the golf club, including the sound made by the club.  
           [0012]    It should be appreciated from the foregoing description that there is a need for an improved golf club head that creates a more consistent flex when striking the ball, improves the club&#39;s feel, and reduces vibration. The present invention satisfies this need and provides further related advantages.  
         SUMMARY OF THE INVENTION  
         [0013]    The present invention provides a solution to counteract the negative side effects described above, by allowing club designers to design a club with an optimal center of gravity, while at the same time lowering the stiffness proximate the sole, creating more consistent flex while striking the ball, improving the feel of the club and reducing vibration.  
           [0014]    According to a preferred embodiment, a golf club head has a body with a striking face, a rear cavity, a hosel and a sole portion. The rear cavity has a cavity wall and a cavity rim, and a recess having a wall is formed proximate the rear cavity. The recess extends generally from the rear cavity toward a bottom of the sole portion. An insert is located within the recess and includes a core and an intermediate layer that at least partially separates the core from the recess wall. The intermediate layer has a hardness and a modulus of elasticity that are less than that of the core, such that when the golf club head is used to strike a golf ball, the resulting vibrations are dissipated by compression of the intermediate layer and friction between the core and the intermediate layer.  
           [0015]    In another preferred embodiment, a golf club head has a body with a striking face, a rear cavity and a sole portion. A recess is formed in the rear cavity and extends generally toward a bottom of the sole portion. There is at least one aperture formed proximate the recess and extending generally from the recess toward the bottom of the sole portion. A cell is inserted within the aperture and has a pin and an outer sleeve. The sleeve has a hardness and a modulus of elasticity that are less than that of the pin, such that when the golf club head is used to strike a golf ball, the resulting vibrations are dissipated by compression of the sleeve and friction between the pin and the sleeve.  
           [0016]    Yet another preferred embodiment includes a main body having a front perimeter, a hosel, a rear portion forming a rear cavity and a sole portion. A first recess is formed in the sole portion and extends generally from the rear cavity toward a bottom of the sole portion. The first recess has a recess wall. A striking face is attached to the front perimeter of the main body, and a hollow portion is formed between the striking face and a wall of the rear cavity. A core and an intermediate layer are located within the first recess, with the intermediate layer at least partially separating the core from the recess wall. A weight is located in the sole portion having a density greater than or equal to a density of the core. The intermediate layer has a hardness and a modulus of elasticity that are less than that of the core, such that when the golf club head is used to strike a golf ball, the resulting vibrations are dissipated by compression of the intermediate layer.  
           [0017]    For purposes of summarizing the invention and the advantages achieved over the prior art, certain advantages of the invention have been described herein above. Of course, it is to be understood that not necessarily all such advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other advantages as may be taught or suggested herein.  
           [0018]    All of these embodiments are intended to be within the scope of the invention herein disclosed. These and other embodiments of the present invention will become readily apparent to those skilled in the art from the following detailed description of the preferred embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]    [0019]FIG. 1 is a rear view of a first preferred embodiment of a golf club head in accordance with the invention.  
         [0020]    [0020]FIG. 1A is a cross-sectional view of the golf club head of FIG. 1, viewed along line A-A, depicting an insert assembly in the recess in the cavity rim and sole bar.  
         [0021]    [0021]FIG. 1B is an exploded view of the golf club head of FIG. 1.  
         [0022]    [0022]FIG. 2 is an exploded view of a second preferred embodiment of a golf club head similar to FIG. 1.  
         [0023]    [0023]FIG. 3 is a rear view of a third preferred embodiment of a golf club head in accordance with the invention.  
         [0024]    [0024]FIG. 3A is a cross-sectional view of the golf club head of FIG. 3, viewed along line A-A, depicting an insert assembly in the recess in the cavity rim and sole bar.  
         [0025]    [0025]FIG. 3B is an exploded view of the golf club head of FIG. 3.  
         [0026]    [0026]FIG. 4 is a rear view of a fourth preferred embodiment of a golf club head in accordance with the invention.  
         [0027]    [0027]FIG. 4A is a cross-sectional view of the golf club head of FIG. 4, viewed along line A-A, depicting an insert assembly in the recess in the cavity rim and sole bar.  
         [0028]    [0028]FIG. 4B is an exploded view of the golf club head of FIG. 4.  
         [0029]    [0029]FIG. 5 is a rear view of a fifth preferred embodiment of a golf club head in accordance with the invention.  
         [0030]    [0030]FIG. 5A is a cross-sectional view of the golf club head of FIG. 5, viewed along line A-A, depicting an insert assembly in the recess in the cavity rim and sole bar.  
         [0031]    [0031]FIG. 5B is an exploded view of the golf club head of FIG. 5.  
         [0032]    [0032]FIG. 6 is a cross-sectional view of a sixth preferred embodiment of a golf club head similar to FIG. 5.  
         [0033]    [0033]FIG. 7 is a cross-sectional view of a seventh preferred embodiment of a golf club head similar to FIG. 5.  
         [0034]    [0034]FIG. 8 is an exploded view of a eighth preferred embodiment of a golf club head similar to FIG. 5.  
         [0035]    [0035]FIG. 8A is a cross-sectional view of the assembled golf club head of FIG. 8, depicting an insert assembly in the recess in the cavity rim and sole bar.  
         [0036]    [0036]FIG. 9 is a cross-sectional view of a ninth preferred embodiment of a golf club head similar to FIG. 1.  
         [0037]    [0037]FIG. 10 is a cross-sectional view of a tenth preferred embodiment of a golf club head similar to FIG. 1 or FIG. 4.  
         [0038]    [0038]FIG. 11 is a cross-sectional view of another preferred embodiment of a golf club head similar to FIG. 6.  
         [0039]    [0039]FIG. 12 is a cross-sectional view of another preferred embodiment of a golf club head.  
         [0040]    [0040]FIG. 13 is a view of elements of the insert for the golf club head of FIG. 13.  
         [0041]    FIGS.  14 A-B are cross-sectional views of other preferred embodiments of a golf club head of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0042]    Referring now to a first embodiment of the present invention shown in FIGS. 1 and 1A, there is shown a golf club head  10  that is similar to many cavity back club heads that are known in the art. The club head  10  includes a body  11  having a heel  12 , a toe  13 , a sole  14 , a front striking face  15 , a top line  16 , and a hosel  17 . The body  11  also has a rear cavity  20  that has a cavity wall  21  that is substantially parallel to the striking face  15 .  
         [0043]    The cavity  20  includes a cavity rim  22  that extends substantially rearwardly from the cavity wall  21  proximate the heel  12 , toe  13 , sole  14  and top line  16 , as shown in FIGS. 1 and 1A. The club head  10  has a perimeter weighting  25  that comprises a mass of material that extends rearwardly from the entirety or a portion of the perimeter of the club head proximate the cavity rim  22 . The perimeter weighting  25  includes a sole bar  26  or mass concentration located proximate the sole  14  so as to provide the desired weight distribution characteristics.  
         [0044]    The perimeter weighting  25  may take various shapes as it wraps from a perimeter of the striking face  15  to the cavity rim  22 . As shown in FIG. 1A, a cavity transition  23  is located between the cavity rim  22  and the sole  14 . The transition  23  may be radiused or may comprise a series of planar surfaces. The body  11  has a raised cavity center weight  27  that protrudes rearwardly from the cavity wall  21  and that is defined by cavity step downs  28 ,  29 , toward the heel  12  and toe  13 , respectively. Alternatively, the cavity wall  21  could be substantially flat (see FIG. 5) or have other shapes to create different performance characteristics and different weight distribution.  
         [0045]    The body  11  is preferably formed of a cast stainless steel, although other known materials known to those skilled in the art may be used. The striking face  15  may be integrally cast with the body  11 , or it may be separately formed and attached to a main body portion  11 ′ comprising the heel  12 , toe  13 , top line  16 , sole  14 , and hosel  17  (see FIGS. 5A, 6 and  7 ). Alternatively, the striking face  15  may be integrally cast or forged with the hosel  17  (not shown) and attached to the remainder of the club head body  11 . A preferred attachment method for the striking face  15  is welding, although other methods known to those skilled in the art may be used.  
         [0046]    As shown in FIGS. 1A and 1B, the body  11  has a recess  60  formed in the sole bar  26  proximate the cavity rim  22 . A preferred method of forming the recess is by casting the recess  60  with the body  11 , although the recess  60  may also be machined into the cast body  11 . The recess  60  extends longitudinally between the heel  12  and the toe  13 . The recess  60  preferably extends downwardly and slightly forward toward the striking face  15  for ease of manufacturing. The recess  60  is defined by a recess wall  61  and a bottom  68 . The bottom  68  of the recess  60  is preferably distanced from the outer surface of the striking face  15  by at least the minimum thickness of the cavity wall  21 .  
         [0047]    An insert assembly  30  is located in the recess  60 , as shown in FIGS. 1A and 1B. The assembly  30  includes a cartridge  32  having apertures  34  that closely receive a plurality of pins  42 . A badge  50  is used to cover the cartridge  32  and pins  42 . Five similarly sized pins  42  are included in the assembly  30  and span a lower central region of the cavity rim  22  proximate the center weight  27 .  
         [0048]    More or less pins  42 , having similar or different shapes, volumes and densities, may be substituted according to the vibration damping, stiffness, feel and weight distribution characteristics that are desired. For ease of manufacture, the pins are preferably cylindrical; however, alternative shapes such as cubes or the like may be used. The apertures are sized and shaped according to the dimensions of the pins. A single pin having a rectangular cross-section generally conforming to the shape of the recess may also be used in the cartridge of the assembly.  
         [0049]    The cartridge  32  is formed of an elastomer, including, for example, thermoplastic materials such as urethane. Other materials may be utilized, so long as the material has a hardness and a modulus of elasticity that are lower than that of the pins  42 . The shape and size of the cartridge may be adjusted according to the desired performance characteristics mentioned previously. The cartridge may be constructed of a translucent material allowing the pins  42  to be visible (see FIG. 4).  
         [0050]    The preferred pin  42  may be constructed of tungsten, nickel, aluminum or stainless steel, for example. Other materials may be used, so long as the material is sufficiently dense and has a relatively high modulus of elasticity. The pin  42  is preferably constructed of material having a density at least as high as the material of the body  11  and may be higher than the material forming the striking face  15 . Preferably, a shallow recess  52  is provided proximate the upper end of the recess wall  61 . A shoulder  54  is formed and receives the badge  50 . The depth of the recess  52  is preferably such that the exterior, visible surface of the badge  50  is flush with the cavity rim  22  when the badge is seated on the shoulder  54 . It is understood, however, that the recess  52  may be omitted and the badge  50  may be placed directly atop the assembly  30  and either raised from or flush with the cavity rim  22 . An adhesive may be used to secure the badge  50  over the recess  52  and/or the assembly  30 . In addition, an intermediate layer of metal or plastic material (not shown) may be used between the badge  50  and the insert  30 .  
         [0051]    The badge  50  may be decorative as well as functional. For example, the badge may be constructed of a translucent material allowing the assembly  30  to be viewed through the badge  50 . Or, slits or cutouts may be provided on the badge  50  to allow viewing of the assembly  30 . Alternatively, the badge  50  may include embossing, engraving or the like, as known to those skilled in the art. As such, metals such as nickel as well as plastic materials may be used for the badge  50 .  
         [0052]    A second preferred embodiment is shown in FIG. 2 and has grooves  35  formed along a bottom of the cartridge  32 ′. Corresponding ribs  36  are formed on the bottom  68  and are received in the corresponding grooves  35 . The ribs may be used to reinforce the lower region of the striking face  15 , add some additional mass in the sole bar  16 , and/or aid in securing the cartridge  32 ′ by providing additional surface area for an adhesive, if used.  
         [0053]    Another preferred embodiment shown in FIGS. 3, 3A and  3 B has an insert assembly  30 ′ that includes cells  40  that are inserted into separate apertures  64  formed in the sole bar  26 . Each cell includes a pin  42  that fits into an aperture  43  at a proximal end  45  of a sleeve  41 . References to the embodiments described herein use like numerals to refer to like elements and their descriptions. In this embodiment the plurality of sleeves  41  are similar in material and function as the single cartridge  32  of the prior embodiment. Instead of a single recess  60 , the plurality of apertures  64  are formed along a similar region as shown by referring to FIGS. 1 and 3. Again, a badge  50  is preferably used to cover the cells  40  of the assembly  30 ′.  
         [0054]    As shown in FIG. 3B, each pin  42  has a proximal end  44  and a distal end  46 . Each sleeve  41  has its aperture  43  sized to easily accept a pin  42 . The sleeve  41  has an open proximal end  45  and a closed distal end  47 . The length of the sleeve  41  is about the same as the length of the pin  42  so that the distal end  46  of the pin  42  may contact the interior of the distal end  47  of the sleeve  41 . A lip  49  at the proximal end  45  of the sleeve  41  may be used to capture the proximal end  44  of the pin  42  and aid in its retention prior to the insertion of the cell  40  into the aperture  64 .  
         [0055]    Referring now to FIG. 3A, it may be seen that the cell  40  preferably does not contact a bottom  66  of the aperture  64 . Also, the proximal ends  44 ,  45  of the pin  42  and sleeve  41 , respectively, are spaced slightly below the badge  50 . The badge  50  is supported in the shallow recess  52  by shoulder  54 . This construction is helpful during the manufacture of the club head.  
         [0056]    An alternative embodiment for a club head in accordance with the present invention is shown in FIGS. 4, 4A and  4 B. A cartridge  132  includes an upper portion  130  that extends onto a lower portion of the center weight  27  and is uncovered. The pins  42  of the assembly  30  are embedded in holes  131  through a lower portion  133  of the cartridge  132  and are made visible through the use of a translucent material for the cartridge  132 . The material of the cartridge  132  may also comprise a high density polymer.  
         [0057]    The features of this embodiment are further made obvious by the concave shaping of the upper portion  130 , such that the assembly  30  does not lie flush with the cavity rim  22 . A variation of this embodiment is for the upper portion  130  of the cartridge  132  to resemble the badge  50  of FIG. 1 by being substantially planar—or alternatively convex—instead of being concave; the upper portion  130  is integral with the lower portion  133  of the cartridge  132 . The pins  42  are embedded within the cartridge using methods, such as press-fitting, known to those skilled in the art. The cartridge is preferably secured with adhesive tape in the bottom of the recess  60 .  
         [0058]    Another club head  10  constructed in accordance with the present invention is shown in FIGS. 5, 5A and  5 B and has a planar cavity wall  21  surrounded by a perimeter weighting  25 . It has a front recess  70  that is formed by the main body  11 ′ and enclosed by the striking face  15 ′. A rear  19  of the striking face  15 ′ is supported by a periphery  18  formed by a front edge of the heel  12 , toe  13 , sole  14  and top line  16  of the body  11 ′.  
         [0059]    Alternatively, the striking face  15 ′ may be supported by a ledge (not shown) surrounding the recess  70  that is formed along the periphery  18  of the body  11 ′. The striking face  15 ′ is preferably welded to the body  11 ′. This construction allows higher deflection of the face at impact since the material of the striking face  15 ′ may have a lower modulus of elasticity than the material of the main body  11 ′, and/or the striking face  15 ′ may be formed thinner than the striking face  15  of conventional cavity back irons.  
         [0060]    The insert assembly  30 ′ is constructed in the sole bar  26  with the damping cells  40  covered by a badge  50 . Modifications to this construction may be made in any manner previously described, such as the substitution of the cells  40  with a cartridge  32  and pins  42  of the alternate insert assembly  30 . Similarly, the badge  50  may be constructed to overlie a portion of the cavity wall  21 , or a recess  60  similar to FIG. 4 may be formed up to a lower part of cavity weight  27  with the badge covering the top of the cartridge.  
         [0061]    A variation of the embodiment of FIG. 5A is shown in FIG. 6 and also has a front recess  70  that is closed by the striking face  15 ′. A lower end of the recess  70  includes a slot  72  that has a weight  80  placed within it. An adhesive is preferably used to secure the weight  80  within the slot  72 . The slot  72  is formed in the sole bar  26  below the insert assembly  30 / 30 ′, and it may extend partially or entirely along the length of the insert assembly  30 / 30 ′. The slot  72  extends rearwardly from the front recess  70  in a directly generally parallel to the sole  14 .  
         [0062]    Yet another variation of the club head of FIG. 5A is shown in FIG. 7 and also has a front recess  70  that is closed by the striking face  15 ′. The cavity wall  21  may include a center weight  27  or may be substantially flat. A recess  98  is formed in a central lower portion of the cavity  20  that includes a part of the cavity wall  21 , the cavity rim  22  and the transition  23 .  
         [0063]    Within the recess  98  is an insert assembly  90  that includes a cartridge  94  and weight  96  along with a much smaller badge  99  than previously described. An upper section  91  of the insert assembly  90  replaces the portion of the cavity wall  21 , a middle section  92  replaces a portion of the cavity rim  22 , and a lower section  93  replaces a portion of the cavity transition  23 . The badge  99  is purely decorative and preferably metallic. It has a logo engraved or embossed on its outer surface.  
         [0064]    The weight  96  is preferably embedded within the cartridge  94  using methods known to those skilled in the art. The materials of the cartridge  94  and weight  96  are chosen from the options previously described. There may be one or a plurality of weights  96  embedded within the cartridge. The mass of the sole bar  26  that is removed by the formation of the recess  98  is substantially replaced or increased by the mass of the weight  96 . Although the weight  96  is shown in a lower portion  97  of the cartridge  94  generally parallel to the sole  14 , it may also extend into an upper portion  95  of the cartridge  94 . An adhesive is preferably used to secure the assembly  90  within the recess  98 .  
         [0065]    The embodiments of FIGS. 5, 6, and  7  having the recess  70  behind the striking face  15 / 15 ′ provide a more rearward center of gravity that may be beneficial to some golfers. Like the embodiments of FIGS.  1 - 4 , they also provide improved flex, feel and vibration damping properties over conventional club heads. The embodiment of FIG. 6, in particular, is more easily manufactured as a hollow iron. Although, the second weight  80  may be inserted and then the striking face  15 ′ may be attached such that the entire rear  19  of the striking face  15 ′ contacts the cavity wall  21  and there is no hollow formed in the club head.  
         [0066]    [0066]FIGS. 8 and 8A depict yet another preferred embodiment similar to the hollow constructions of FIGS. 5, 6 and  7 . As in FIG. 6, an additional weight  82  is included. The insert assembly  31 ″ thus includes pins  42 , a cartridge  32  and the weight  82 . Preferably the material of the weight  82  is a tungsten powder polymer, although any material may be used so long as it has a density greater than that of the body. The inclusion of the weight  82  in the sole bar  26  allows additional options with regard to the weight distribution of the club head  10  and the resultant flex and damping properties.  
         [0067]    The weight  82  is placed within the recess  60 , proximate the cartridge  32  and pins  42 . The weight  82  may be located as shown at the bottom of the recess; however, it may alternatively be placed above the pins, as desired. In addition, cells  40  may be used, wherein a plurality of apertures  64  are provided in the sole bar to receive the cells  40 . The weight  82  may include a corresponding number of smaller weight elements co-located within the apertures  64  with the cells  40 , or a single, adjoining recess for the weight  82  may be included above the apertures and cells.  
         [0068]    Another embodiment shown in cross-section in FIG. 9 preferably comprises 5 pins  42  that are closely received in apertures of a cartridge  232 . The cartridge  232  is preferably formed of a loaded polymer, such as tungsten powder in a nylon or urethane resin. A lower surface  234  of the cartridge  232  is shaped to conform to the bottom surface of the recess  60  formed in the rear of the club head. It is understood that the geometry of the recess  60  is at least partly dictated by the loft angle of the club head and its effect on the shape of the sole bar  26 .  
         [0069]    A cover  230  is preferably formed of a clear polymer and may be of a lesser density that the lower cartridge portion. The cover  230  has mating apertures to closely receive the pins  42  and thereby secure them. An adhesive is preferably used between the contacting surfaces of the cover  230  and cartridge  232 . An upper surface  222  of the cover  230  is contoured for a smooth transition along the cavity rim  22 .  
         [0070]    The embodiment of FIG. 10 depicts an opening  200  provided at an upper end  206  of a cartridge  202 . A plurality of pins  42  or a weight  204  may be placed within the cartridge  202 . The weight  204  may comprise a single or multiple elements, such as tungsten bars. The cartridge  202  is preferably formed of a thin, high density polymer or standard urethane that accepts the pins or weight without undue effort during club head manufacture. The opening  200  may comprise a single slit at the upper end, or the opening  200  may comprise a plurality of apertures. For a plurality of apertures, a lower end  208  of the cartridge  202  may have at least one opening for insertion of the pins  42  or weight  204 .  
         [0071]    A variation of the embodiment of FIG. 6 is shown in FIG. 11. An insert assembly  30  ( 30 ′) is provided at a lower portion of the cavity rim  22 . Instead of a slot  72  extending rearwardly from a lower end of the recess  70 , a slot  172  is formed in the perimeter weight  25  of the sole bar  26  through the cavity transition  23 . A weight  80  is closely received in the slot  172  and may be further secured with adhesive.  
         [0072]    The embodiment of FIG. 12, with its insert assembly  30 ″ shown separately in FIG. 13, has an optional opening  200  for viewing of the assembly  30 ″. The insert assembly  30 ″ preferably comprises pins  42  embedded within a cartridge  210  and protected by a cover  150 . Because the cover  150  must endure the same impact forces as the sole bar  26  and keep out debris from the recess  160 , the material of the cover preferably comprises a metal having a density approximately equal to or greater than the material of the club head body  11 ′.  
         [0073]    Two similar embodiments are shown in FIGS. 14A and 14B, comprising a dual weight configuration within a low density cartridge  240 ,  250 . A weight assembly  330  configured as in FIG. 14A provides a higher mass contribution to the club head than the assembly  330  of FIG. 14B. Also, the assembly  330  of FIG. 14A is behind a greater area of the recess  70  and striking face  15 ′ than the assembly  330  of FIG. 14B.  
         [0074]    The cartridge  240 ,  250  is preferably formed of a polymer with a density of approximately 1 g/cc. The cartridge  240  includes an open lower end  334  having a lip  336  to aid in maintaining weights  84 ,  86  in place during manufacture. The cartridge  250  includes an open end  338  without a lip  336 . In the weight assembly  330  the smaller weight  84  is located between the cartridge  240 ,  250  and the larger weight  86 . Weight  84  preferably comprises a material such as aluminum having a density of about 2.7 g/cc, while weight  86  preferably comprises a material having a significantly larger density, such as 18 g/cc or so. Manipulation of the club head center of gravity may be made by changing the places of the two weights  84 ,  86  within the cartridge  240 ,  250 . Also, the cartridge  240  may be used for the assembly  330  in the cavity transition  23  instead of the cartridge  250 ; similarly, the cartridge  250  may be used for the assembly  330  in the cavity rim  22  instead of the cartridge  240 .  
         [0075]    The embodiments of FIGS.  9 - 14 B are shown and described with reference to a body  11 ′ having a front recess  70  for receiving a separate striking face  15 ′; however, the present invention does not preclude these embodiments having a body  11  integrally including the striking face  15 . Although the invention has been disclosed in detail with reference only to the preferred embodiments, those skilled in the art will appreciate that golf club heads can be made without departing from the scope of the invention. Accordingly, the invention is defined only by the claims set forth below.