Abstract: A golf club head system and a golf club head for inclusion into a golf club are provided. The golf club head system includes two or more rear or secondary body members, each configured for interchangeable attachment to a front or main body member. Each rear body member may have a different external shape, and each rear body member may have a different combination of center-of-gravity and moment-of-inertia characteristics. The system further includes a detachable attachment element for interchangeably and detachably attaching the rear body members to the front body member. The system may further include the front body member, wherein the front body member has a striking surface.

Abstract: Wood-type golf club heads include: (a) a club head body including heel, toe, crown, sole, and weighted rear portions; and (b) a variable thickness ball striking face. The club head body parts and weighted portion(s) may be arranged such that the club head has a moment of inertia about a vertical axis passing through the club head center of gravity of at least 5000 g-cm2. Such club heads may include: (a) a cup face member including a ball striking face portion and a return portion; (b) sole and crown portions engaged with the return portion; (c) a rear body member engaged with the crown and/or sole portions; (d) a weight member at the club head rear; and/or (e) a hosel member engaged with the cup face member, the crown portion, and/or the sole portion.

Abstract: A golf club head system and a golf club head for inclusion into a golf club are provided. The golf club head includes a main body member and a secondary body member. The main body member has a striking surface, a sole portion, a crown portion, and a rear face substantially opposed to the striking surface. The main body member defines an at least substantially enclosed main body cavity. The secondary body member is attached to the main body member and extends at least substantially over the entire rear face of the main body member. The golf club head system includes two or more secondary body members, each configured for interchangeable attachment to a main body member. Each secondary body member defines an internal concavity, has a different external shape, and has a different combination of center-of-gravity and moment-of-inertia characteristics.

Abstract: A ball striking device, such as a golf club, includes a head with a face having a ball striking surface configured for striking a ball, a main body member connected to the face and having an engagement surface located in the rear side, a removable body member removably connected to the main body member, and a connecting element removably connecting the removable body member to the main body member. The connecting element includes a moveable engaging member that is moveable between a locked position, where the engaging member engages the engagement surface to retain the removable body member to the main body member, and an unlocked position, where the engaging member does not engage the engagement surface and the removable body member is removable from the main body member.

Abstract: A golf club head is disclosed that includes a weight integral to a bridge member extending across a cavity back golf club head. The weight modifies a position of a center of gravity of the golf club head. The weight is independently movable in multiple directions to further vary the center of gravity of a golf club head.

Abstract: A golf club head system and a golf club head for inclusion into a golf club are provided. The golf club head includes a main body member and a secondary body member. The main body member has a striking surface, a sole portion, a crown portion, and a rear face substantially opposed to the striking surface. The main body member defines an at least substantially enclosed main body cavity. The secondary body member is attached to the main body member and extends at least substantially over the entire rear face of the main body member. The golf club head system includes two or more secondary body members, each configured for interchangeable attachment to a main body member. Each secondary body member defines an internal concavity, has a different external shape, and has a different combination of center-of-gravity and moment-of-inertia characteristics.

Abstract: A golf club head includes a body member having a ball striking face, a crown, a toe, a heel, a sole, a rear, and a hosel region. The heel includes an airfoil-like surface shaped like the leading edge of an airfoil that extends over a majority of the length of the heel. The back may include a Kammback feature having a concavity extending from the heel-side to the toe-side of the back. The heel-side edge of the concavity may be shaped like the leading edge of an airfoil. Further, the sole may include a diffuser that extends at an angle of from approximately 10 degrees to approximately 80 degrees from a moment-of-impact trajectory direction. A hosel fairing that extends from the hosel region toward the toe may also be provided on the crown. A golf club including the golf club head is also disclosed.

Abstract: A golf club head may include a body member having a ball striking face, a crown, a toe, a heel, a sole, a back, and a hosel region located at the intersection of the ball striking face, the heel, the crown and the sole. The crown may have a relatively round rear-side edge profile, as viewed from above. The sole may have a relatively square rear-side edge profile, as viewed from below. The rear-side edge of the sole may extend rearwardly beyond the rear-side edge of the crown along at least a portion of the back, as viewed from above. Further, the heel may have an airfoil-like surface in the forward portion of the heel. A golf club including the golf club head is also provided.

Abstract: Golf club heads include: (a) a body member constructed, at least in part, from cellular structure material; (b) a ball striking face engaged or integrally formed with the body member; and/or (c) a shaft member engaged with the body member. Weight savings realized through the use of lightweight cellular structure materials allows additional weight to be placed at other desired locations in the club head structure. By adjusting and selectively placing weight in the club head structure, the club head's moment of inertia, center of gravity, and/or stability characteristics may be favorably affected and/or the resulting ball flight may be influenced and/or customized to a specific individual golfer, to provide a more controlled, consistent, and/or straight ball flight.

Abstract: Golf club heads (e.g., drivers, fairway woods, wood-type hybrid clubs, or the like) according to at least some example aspects of this invention include: (a) a heel; (b) a toe; (c) a crown; (d) a sole; (e) a striking face; (f) a cavity, wherein the cavity is at least partially open; (g) a rear face opposite the striking face, the rear face defining an opening to the cavity; and (h) a rear body member configured to be inserted into the opening. The rear body member may be releasably engaged with the opening to the cavity, rear face, and/or other portion of the club head body.

Abstract: Wood-type golf club heads (e.g. drivers, fairway woods, wood-type hybrid clubs, or the like) include: (a) a ball striking face; (b) a club head body engaged or integrally formed with the ball striking face, wherein the club head body includes a crown portion, the crown portion including a fixed portion proximal to the ball striking face, and a removable weight portion, which is configured to be coupled with the fixed portion on a side of the crown potion away from the ball striking face. The club head body may further include an interior portion with a frame member defined therein. The crown weight may further include a weight member attached to the frame member, the weight member including at least one receptacle defined therein. The removable weight portion may further include at least one weight insert supported within the weight member in the at least one receptacle.

Abstract: Golf club heads include: (a) a body having a ball-striking face and a rear face, the body defining a cavity; (b) a bridge member extending across the cavity, wherein the bridge member is provided to affect, at least in part, a position of a center of gravity of the club head; and (c) a feel altering element provided between the bridge member and the rear face. The feel altering element may affect a wide variety of parameters that relate to the “feel” of the golf club head when it strikes a golf ball, such as the sound produced by the club head during the strike, the vibrational response of the club head during the strike, the swing characteristics of the club head (e.g., weight, center of gravity position, etc.), and the like.

Abstract: Golf club heads are releasably engaged with shafts so that the club heads and shafts can be readily interchanged and/or so that the shaft position with respect to the club head can be readily changed. Assemblies for connecting the club head and shaft may include: (a) a shaft engaging member including a rotation-inhibiting structure; (b) a club head engaging member including a shaft-receiving chamber and a retaining structure for engaging the rotation-inhibiting structure; and (c) a securing system for releasably securing the shaft engaging member with respect to the club head engaging member. The club head and shaft may be changed by releasing the securing system and exchanging the original parts with different parts. Furthermore, the shaft may be bent or otherwise extend at an angle from the shaft engaging member so as to allow adjustment of the shaft position with respect to the club head.

Abstract: Golf club heads include: (a) a body having a ball-striking face and a rear face, the body defining a cavity; (b) a bridge member extending across the cavity, wherein the bridge member is provided to affect, at least in part, a position of a center of gravity of the club head; and (c) a feel altering element provided between the bridge member and the rear face. The feel altering element may affect a wide variety of parameters that relate to the “feel” of the golf club head when it strikes a golf ball, such as the sound produced by the club head during the strike, the vibrational response of the club head during the strike, the swing characteristics of the club head (e.g., weight, center of gravity position, etc.), and the like.

Abstract: Wood-type golf club heads (e.g., drivers, fairway woods, wood-type hybrid clubs, or the like) include: (a) a ball striking face; (b) a club head body engaged or integrally formed with the ball striking face, wherein the club head body includes a crown portion, the crown portion including a fixed portion proximal to the ball striking face, and a removable weight portion, which is configured to be coupled with the fixed portion on a side of the crown portion away from the ball striking face. The club head body may further include an interior portion with a frame member defined therein. The crown weight may further include a weight member attached to the frame member, the weight member including at least one receptacle defined therein. The removable weight portion may further include at least one weight insert supported within the weight member in the at least one receptacle.

Abstract: Golf club heads are releasably engaged with shafts so that the club heads and shafts can be readily interchanged and/or so that the shaft position with respect to the club head can be readily changed. Assemblies for connecting the club head and shaft may include: (a) a shaft engaging member including a rotation-inhibiting structure; (b) a club head engaging member including a shaft-receiving chamber and a retaining structure for engaging the rotation-inhibiting structure; and (c) a securing system for releasably securing the shaft engaging member with respect to the club head engaging member. The club head and shaft may be changed by releasing the securing system and exchanging the original parts with different parts. Furthermore, the shaft may be bent or otherwise extend at an angle from the shaft engaging member so as to allow adjustment of the shaft position with respect to the club head.

Abstract: Golf club heads are releasably engaged with shafts so that the club heads and shafts can be readily interchanged and/or so that the shaft position with respect to the club head can be readily changed. Assemblies for connecting the club head and shaft may include: (a) a shaft engaging member including a rotation-inhibiting structure; (b) a club head engaging member including a shaft-receiving chamber and a retaining structure for engaging the rotation-inhibiting structure; and (c) a securing system for releasably securing the shaft engaging member with respect to the club head engaging member. The club head and shaft may be changed by releasing the securing system and exchanging the original parts with different parts. Furthermore, the shaft may be bent or otherwise extend at an angle from the shaft engaging member so as to allow adjustment of the shaft position with respect to the club head.

Abstract: Golf club heads are releasably engaged with shafts so that the club heads and shafts can be readily interchanged and/or so that the shaft position with respect to the club head can be readily changed. Assemblies for connecting the club head and shaft may include: (a) a shaft engaging member including a rotation-inhibiting structure; (b) a club head engaging member including a shaft-receiving chamber and a retaining structure for engaging the rotation-inhibiting structure; and (c) a securing system for releasably securing the shaft engaging member with respect to the club head engaging member. The club head and shaft may be changed by releasing the securing system and exchanging the original parts with different parts. Furthermore, the shaft may be bent or otherwise extend at an angle from the shaft engaging member so as to allow adjustment of the shaft position with respect to the club head.

Abstract: Ball striking devices, such as golf club heads (including putter heads), have a high moment of inertia about their center, to help prevent twisting and mis-hits, particularly when the ball striking device hits the ball at a somewhat off-center position. The ball striking head of the ball striking device may be structured and/or weighted (optionally with separately attachable weight elements) to have a moment of inertia about a center of the ball striking surface of at least 10,000 g/cm2, and in some examples, the moment of inertia may be at least 11,000 g/cm2, or even at least 12,000 g/cm2. In some examples, the moment of inertia may be at least 20,000 g/cm2, or even at least 25,000 g/cm2 or at least 28,000 g/cm2.

Abstract: Ball striking devices, such as golf club heads (including putter heads), have a high moment of inertia about their center, to help prevent twisting and mis-hits, particularly when the ball striking device hits the ball at a somewhat off-center position. The ball striking head of the ball striking device may be structured and/or weighted (optionally with separately attachable weight elements) to have a moment of inertia about a center of the ball striking surface of at least 10,000 g/cm2, and in some examples, the moment of inertia may be at least 11,000 g/cm2, or even at least 12,000 g/cm2. In some examples, the moment of inertia may be at least 20,000 g/cm2, or even at least 25,000 g/cm2 or at least 28,000 g/cm2.