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: 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: 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: Wood-type golf clubs and/or golf club heads include a club head body having a breadth to length ratio of at least 0.9, optionally a club head volume of at least 450 cubic centimeters, and a diagonal dimension of at least 75% of a theoretical maximum diagonal dimension (as measured along a diagonal of a bounding box enclosing the club head body and defined by the length dimension and the breadth dimension). In some examples, the diagonal dimension may be at least 80%, 85%, or even 90% of the theoretical maximum diagonal dimension. Additionally or alternatively, if desired, at least one horizontal cross section of the club head body will enclose or encompass an area of at least 0.8×BL, at least 0.85×BL, at least 0.9×BL, or even at least 0.95×BL.

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: 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 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: A cavity back golf club head having an interchangeable bridge member is disclosed. The interchangeable bridge member extends across a rear cavity connecting a heel and a toe of the golf club head to control the trajectory of a golf ball.

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: Ball striking devices may include: (a) a sole member; (b) at least one intermediate body member; (c) a crown member; and (d) a face member. The materials making up the sole member, the intermediate body member(s), and the crown member may be selected so that the densities of the materials generally increase as one moves in a direction from the sole member toward the crown member. Such devices may be formed as golf club heads and/or golf clubs (such as “wood-type” golf clubs and golf club heads).

Abstract: Wood-type golf club heads include: (a) a ball striking face member; and (b) a club head body attached to or integrally formed with the face member. One body component of the club head (e.g., a weight or cover member) may be formed from a transparent, partially transparent, or translucent material. In some club head structures, an external weight member may extend around a part of a club head body member and beyond or outside of at least a portion of the body member's exterior perimeter (e.g., rearwardly, laterally toward a toe side, and/or laterally toward a heel side of the club head body, beyond the exterior perimeter portion, when viewed from overhead). Golf club structures that include golf club heads, e.g., of the types described above, and methods of constructing and/or using such clubs and club heads, also are described.

Abstract: Ball striking devices may include: (a) a sole member; (b) at least one intermediate body member; (c) a crown member; and (d) a face member. The materials making up the sole member, the intermediate body member(s), and the crown member may be selected so that the densities of the materials generally increase as one moves in a direction from the sole member toward the crown member. Such devices may be formed as golf club heads and/or golf clubs (such as “wood-type” golf clubs and golf club heads).

Abstract: Ball striking devices, such as golf club heads (including putter heads), include devices within and/or otherwise engaged with the ball striking head that allow users to selectively change the sound and/or other aspects of the “feel” associated with using the ball striking device to strike a ball. In this manner, a user, a club fitter, or the like can freely customize and adjust the sound and/or other aspects of the ball striking device's feel to correspond to a particular user's preferences.

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 cylindrical structure having a cylindrical interior chamber for receiving a golf club shaft, a rotation-inhibiting structure, and a securing structure; and (b) a securing system for releasably engaging the securing structure. 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 connection assembly so as to allow adjustment of the shaft position with respect to the club head.

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: Ball striking devices may include: (a) a sole member; (b) at least one intermediate body member; (c) a crown member; and (d) a face member. The materials making up the sole member, the intermediate body member(s), and the crown member may be selected so that the densities of the materials generally increase as one moves in a direction from the sole member toward the crown member. Such devices may be formed as golf club heads and/or golf clubs (such as “wood-type” golf clubs and golf club heads).

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.