TECHNICAL FIELD

[0001] The invention relates generally to ball striking devices, such as iron-type golf clubs and heads. Certain aspects of this invention relate to iron-type golf cl ubs havin g multi-piece heads with a "hot zone" that extends proximate the bottom edge of the face.

BACKGROUND

[0002] Golf is enjoyed by a wide variety of players - players of different genders, and players of dramatically different ages and skill levels. Golf is somewhat unique in the sporting world in that such di verse collections of players can play together in golf outings or events, even in direct competition with one another (e.g., using handicapped scoring, different tee boxes, etc.), and still enjoy the golf outing or competition. These factors, together with increased golf programming on television (e.g., golf tournaments, golf news, golf history, and/or other golf programming) and the rise of well known golf superstars, at least in part, have increased golfs popularity in recent years, both in the United States and across the world.

[0003] Golfers at all skill levels seek to improve their performance, lower their golf scores, and reach that next performance "level." Manufacturers of all types of golf equipment have responded to these demands, and recent years have seen dramatic changes and improvements in golf equipment. For example, a wide range of different golf ball models now are available, with some balls designed to fly farther and straighter, provide higher or flatter trajectory, provide more spin, control, and feel (particularly around the greens), etc.

[0004] Being the sole instrument that sets a golf ball in motion during play, the golf club also has been the subject of much technological research and advancement in recent years. For example, the market has seen improvements in golf club heads, shafts, and grips in recent years. Additionally, other technological advancements have been made in an effort to better match the various elements of the golf club and characteristics of a golf ball to a particular user's swing features or characteristics (e.g., club fitting technology, ball launch angle measurement technology, etc.). [0005] Despite the various technological improvements, golf remains a difficult game to play at a high level. For a golf ball to reliably fly straight and in the desired direction, a golf club must meet the golf ball square (or substantially square) to the desired target path. Moreover, the golf club must meet the golf ball at or close to a desired location on the club head face (i.e., on or near a "desired" or "optimal" ball contact location) to reliably fly straight, in the desired direction, and for a desired distance. Off-center hits may tend to "twist" the club face when it contacts the ball, thereby sending the ball in the wrong direction, imparting undesired hook or slice spin, and/or robbing the shot of distance. Club face/ball contact that deviates from squared contact and/or is located away from the club's desired ball contact location, even by a relatively minor amount, also can launch the golf ball in the wrong direction, often with undesired hook or slice spin, and/or can rob the shot of distance. When the club face is not square at the point of engagement, the golf ball may fly in an unintended direction and/or may follow a route that curves left or right, ball flights that are often referred to as "pulls," "pushes," "draws," "fades," "hooks," or "slices," or may exhibit more boring or climbing trajectories. Accordingly, club head features that can help a user keep the club face square with the ball would tend to help the ball fly straighter and truer, in the desired direction, and often with improved and/or reliable distance.

[0006] The energy or velocity transferred to the ball by a golf club also may be related, at least in part, to the "coefficient of restitution" (or "COR") of the club face at the point of contact. The maximum COR for golf club heads is currently limited by the USGA at 0.83. Generally, a club head will have an area of highest response relative to other areas of the face, such as having the highest COR, which imparts the greatest energy and velocity to the ball, and this area is typically positioned at the desired ball contact location, usually at the center of the face. Iron- type golf clubs are often used to hit a ball sitting directly on the playing surface, and thus, frequently impact the ball at locations below the center of the face. Occasionally, a golfer may mis-hit a ball with an iron-type golf club such that the center of impact is on or near the bottom edge of the ball striking face, which can cause much lower ball flight than desired. This lower ball flight can rob the shot of distance, such as for longer irons, or can cause the ball to overshoot the desired target, such as for shorter irons or shorter shots. Accordingly, an iron-type golf club may benefit from a design that assists in imparting greater loft to a golf ball that is mis-hit too low on the face. [0007] The present device and method are provided to address the problems discussed above and other problems, and to provide advantages and aspects not provided by prior ball striking devices of this type. A full discussion of the features and advantages of the present invention is deferred to the following detailed description, which proceeds with reference to the

accompanying drawings.

BRIEF SUMMARY

[0008] The following presents a general summary of aspects of the invention in order to provide a basic understanding of the invention. This summary is not an extensive overview of the invention, it is not intended to identify key or critical elements of the invention or to delineate the scope of the invention. The following summary merely presents some concepts of the invention in a general form as a prelude to the more detailed description provided below.

[0009] Aspects of the invention relate to ball striking devices, such as golf clubs, with a head that includes a face configured for striking a ball and a body connected to the face, the body being adapted for connection of a shaft thereto. Various example structures of heads described herein include an iron-type head that has a face having a ball striking surface defined thereon and a body connected to the face. The body has a sole member extending rearward from a bottom edge of the face, and the sole member has a sole surface configured to confront the playing surface. The head has an elongated channel located in the sole member, and the channel is recessed from the sole surface, extends along at least a portion of the bottom edge of the face and is spaced from the bottom edge.

[0010] According to one aspect, the channel is generally parallel to the bottom edge of the face.

[0011] According to another aspect, the channel has a depth of recession from the sole surface. In one embodiment, the depth of the channel is tapered, such that the depth of the channel is greater at a center of the channel than at opposed ends of the channel. In another embodiment, the depth of the channel is constant over a majority of a length of the channel. [0012] According to yet another aspect, the channel has an elongated length defined between a first end and a second end, and the first end and the second end of the channel are located on the sole surface.

[0013] According to a further aspect, the channel is elongated between a first and a second end, and the channel is defined by two edges extending between the first and second ends. In one embodiment, the edges are linear and parallel to each other. In another embodiment, the edges are curvilinear. In a further embodiment, at least one of the edges is generally parallel to the bottom edge of the face.

[0014] According to a still further aspect, the channel comprises a trough and opposed side walls extending from the trough to edges of the channel. In one embodiment, at least one of the side walls is parallel to the face when viewed in cross-section. In another embodiment the trough has a rounded shape when viewed in cross-section. In a further embodiment, the channel has a width measured between the side walls that tapers inwardly or outwardly.

[0015] Additional aspects of the invention relate to an iron-type golf club head that includes a face having a ball striking surface and a body connected to the face. The body includes peripheral walls extending rearward from outer edges of the face and a rear cavity defined by the rear surface of the face and the peripheral walls. The head further includes an elongated channel located in a first of the peripheral walls adjacent to a first of the outer edges of the face that adjoins the first peripheral wall. Additionally, the channel is defined by a first end, a second end, and two edges extending between the first and second ends, and the channel includes a trough that is recessed from the first peripheral wall and two opposed side walls extending from the trough to the edges of the channel . The channel is spaced rearwardly from the first outer edge of the face, and the edges of the channel are generally parallel to the first outer edge of the face.

[0016] Further aspects of the invention relate to an iron-type golf club head that includes a face having a ball striking surface and a body connected to the face. The body includes a plurality of peripheral walls extending rearward from outer edges of the face. The peripheral walls include a sole member extending rearward from a bottom edge of the face, with the sole member having a sole surface configured to confront the playing surface. An elongated channel is located in the sole member, and the channel is defined by a first end located on the sole surface, a second end located on the sole surface, and two edges extending across the sole surface between the first and second ends. The channel includes a trough that is recessed from the sole surface and two opposed side walls extending from the trough to the edges of the channel, such that the channel is spaced rearwardly from the bottom edge of the face and the edges of the channel are generally parallel to the bottom edge.

[0017] Other aspects of the invention relate to golf clubs that include a golf club head as described above and a shaft connected to the head. Such golf clubs may be iron-type golf clubs.

[0018] Other features and advantages of the invention will be apparent from the following description taken in conjunction with the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] To allow for a more full understanding of the present invention, it will now be described by way of example, with reference to the accompanying drawings in which:

FIG. 1 is a front view of an illustrative embodiment of an iron-type ball striking device according to aspects of the present invention;

FIG. 2 is a front view of an illustrative embodiment of a head of the ball striking device of FIG. 1;

FIG. 3 is a bottom view of the head of FIG. 2;

FIG. 4 is a rear view of the head of FIG. 2;

FIG. 5 is a cross-section view of the head of FIG. 2, taken along lines 5-5 of FIG. 2; FIG. 5 A is a magnified view of a portion of the head as shown in FIG. 5;

FIG. 6 is a cross-section view of the head of FIG. 2, taken along lines 6-6 of FIG. 2; FIG. 6A is a magnified view of a portion of the head as shown in FIG. 6;

FIG. 7 is a cross-section view of the head as shown in FIG. 5, during impact with a ball; FI G. 8 is a cross-section view of the head as shown in FIG. 7, immediately after the impact with the ball;

FIG. 9 is a cross-section view of an example of an existing iron-type ball striking device, immediately after impact with a ball;

FIG. 10 is a front view of a second illustrative embodiment of a head of a ball striking device; FIG. 11 is a bottom view of the head of FIG. 10;

FIG. 12 is a rear view of the head of FIG . 10;

FIG. 13 is a cross-section view of the head of FIG. 10, taken along lines 13-13 of FIG. 10;

FIG. 13A is a magnified view of a portion of the head as shown in FIG. 13;

FIG. 14 is a cross-section view of the head of FIG. 10, taken along lines 14-14 of FIG. 10;

FIG. 14A is a magnified view of a portion of the head as shown in FIG. 14;

FIG. 15 is a front view of a third illustrative embodiment of a head of a ball striking device;

FIG. 16 is a bottom view of the head of FIG . 15;

FIG. 17 is a cross-section view of the head of FIG. 15, taken along lines 17-17 of FIG. 15;

FIG. 17A is a magnified view of a portion of the head as shown in FIG. 17;

FIG. 18 is a cross-section view of the head of FIG. 15, taken along lines 18-18 of FIG. 15;

FIG. 18 A is a magnified view of a portion of the head as shown in FIG. 18;

FIG. 19 is a magnified cross-section view of a portion of a fourth illustrative embodiment of a head of a ball striking device;

FIG. 20 is a magnified cross-section view of a portion of a fifth illustrative embodiment of a head of a bal l striking device;

FIG. 21 is a magnified cross-section view of a portion of a sixth illustrative embodiment of a head of a ball striking device;

FIG. 22 is a magnified cross-section view of a portion of a seventh illustrative embodiment of a head of a ball striking device;

FIG. 23 is a front view of a fourth illustrative embodiment of a head of a ball striking device;

FIG. 24 is a bottom view of the head of FIG. 23;

FIG. 25 is a rear view of the head of FIG. 23;

FI G. 26 is a cross-section view of the head of FIG. 23, taken along lines 26-26 of FIG.

23; FIG. 27 is a cross-section view of the head of FIG. 23, taken along lines 27-27 of FIG.

23;

FIG. 27A is a magnified view of a portion of the head as shown in FIG. 27;

FIG. 28 is a bottom view of a fifth illustrative embodiment of a head of a ball striking device;

FIG. 29 is a bottom view of a sixth illustrative embodiment of a head of a ball striking device;

FIG. 30 is a cross-section view of the head of FIG. 29, taken along lines 30-30 of FIG.

29; and

FIG. 30 A is a magnified view of a portion of the head as shown in FIG. 30. DETAILED DESCRIPTION

[0020] In the following description of various example structures according to the invention, reference is made to the accompanying drawings, which form a part hereof, and in which are shown by way of i llustration various example devices, systems, and environments in which aspects of the invention may be practiced. It is to be understood that other specific arrangements of parts, example devices, systems, and environments may be utilized and structural and functional modifications may be made without departing from the scope of the present invention. Also, while the terms "top," "bottom," "front," "back," "side," "rear," and the like may be used in this specification to describe various example features and elements of the invention, these terms are used herein as a matter of convenience, e.g., based on the example orientations shown in the figures or the orientation during typical use. Additionally, the term "plurality," as used herein, indicates any number greater than one, either disjunctively or conjunctively, as necessary, up to an infinite number. Nothing in this specification should be construed as requiring a specific three dimensional orientation of structures in order to fall within the scope of this invention. Also, the reader is advised that the attached drawings are not necessarily drawn to scale.

[0021] The following terms are used in this specification, and unless otherwise noted or clear from the context, these terms have the meanings provided below.

[0022] "Ball striking device" means any device constructed and designed to strike a ball or other similar objects (such as a hockey puck). In addition to generically encompassing "ball striking heads," which are described in more detail below, examples of "ball striking devices" include, but are not limited to: golf clubs, putters, croquet mallets, polo mallets, baseball or Softball bats, cricket bats, tennis rackets, badminton rackets, field hockey sticks, ice hockey sticks, and the like.

[0023] "Ball striking head" means the portion of a "ball striking device" that includes and is located immediately adjacent (optionally surrounding) the portion of the ball striking device designed to contact the ball (or other object) in use. In some examples, such as many golf clubs and putters, the ball striking head may be a separate and independent entity from any shaft or handle member, and it may be attached to the shaft or handle in some manner.

[0024] The terms "shaft" and "handle" are used synonymously and interchangeably in this specification, and they include the portion of a ball striking device (if any) that the user holds during a swing of a ball striking device.

[0025] " I ntegral joining technique" means a technique for joining two pieces so that the two pieces effectively become a single, integral piece, including, but not limited to, irreversible joining techniques, such as adhesively joining, cementing, and welding (including brazing, soldering, or the like), where separation of the joined pieces cannot be accomplished without structural damage thereto.

[0026] "Generally parallel" means that a first line, segment, plane, edge, surface, etc. is approximately (in this instance, within 5%) equidistant from with another line, plane, edge, surface, etc., over at least 50% of the length of the first line, segment, plane, edge, surface, etc.

[0027] "Transverse" means extending across or in a cross direction to a line, plane, edge, surface, etc., defined at an actual or virtual intersection point, but does not necessarily imply a perpendicular intersection.

[0028] "Substantially flush" means that a surface of one article is level and aligned with the surface of an adjacent article, such that the two surfaces form a substantially flat single surface, within a tolerance of +/- 0.005 inches. [0029] In general, aspects of this invention relate to ball striking devices, such as golf club heads, golf clubs, putter heads, putters, and the like. Such ball striking devices, according to at least some examples of the invention, may include a ball striking head and a ball striking surface. In the case of a golf club, the ball striking surface is a substantially flat surface on one face of the ball striking head. Some more specific aspects of this invention relate to iron-type golf clubs and golf club heads, including long irons, short irons, wedges, etc. Alternately, some aspects of this invention may be practiced with hybrid clubs, chippers, and the like, or wood-type golf clubs and the like.

[0030] According to various aspects of this invention, the ball striking device may be formed of one or more of a variety of materials, such as metals (including metal alloys), ceramics, polymers, composites (including fiber-reinforced composites), and wood, and may be formed in one of a variety of configurations, without departing from the scope of the invention. In one illustrative embodiment, some or all components of the head, including the face and at least a portion of the body of the head, are made of metal. It is understood that the head may contain components made of several different materials, including carbon-fiber and other components. Additionally, the components may be formed by various forming methods. For example, metal components (such as titanium, aluminum, titanium alloys, aluminum alloys, steels (including stainless steels), and the like) may be formed by forging, molding, casting, stamping, machining, and/or other known techniques. In another example, composite components, such as carbon fiber-polymer composites, can be manufactured by a variety of composite processing techniques, such as prepreg processing, powder-based techniques, mold infiltration, and/or other known techniques.

[0031] The various figures in this appl ication il lustrate examples of ball striking devices according to this invention. When the same reference number appears in more than one drawing, that reference number is used consistently in this specification and the drawings refer to the same or similar parts throughout.

[0032] At least some examples of ball striking devices according to this invention relate to golf club head structures, including heads for wood-type golf clubs, such as drivers, as well as long iron clubs (e.g., driving irons, zero irons through five irons), short iron clubs (e.g., six irons through pitching wedges, as well as sand wedges, lob wedges, gap wedges, and/or other wedges), hybrid clubs, and putters. Such devices may include a one-piece construction or a multiple-piece construction. Example structures of ball striking devices according to this invention will be described in detail below in conjunction with FIG. 1, which illustrates an example of a ball stri king device 100 in the form of an iron-type golf club, in accordance with at least some examples of this invention.

[0033] FIG. 1 illustrates a ball striking device 100 in the form of a golf iron, in accordance with at least some examples of this invention, and illustrative embodiments of heads 102, et seq., of ball striking devices 100 of this type are shown in FIGS. 2-18A and 23-30A. The golf club head 102 of FIG. 1 may be representative of any iron-type golf club head in accordance with examples of the present invention. As shown in FIG. 1, the ball striking device 100 includes a ball striking head 102 and a shaft 104 connected to the ball striking head 102 and extending therefrom. The ball striking head 102 of the ball striking device 100 of FIG. 1 has a face 112 connected to a body 108, with a hosel 109 extending therefrom. Any desired hosel and/or head/shaft interconnection structure may be used without departing from this invention, including conventional hosel or other head/shaft interconnection structures as are known and used in the art, or an adjustable, releasable, and/or interchangeable hosel or other head/shaft interconnection structure such as those shown and described in U.S. Patent 6,890,269 dated May 10, 2005, in the name of Bruce D. Burrows, U.S. Published Patent Application No.

2009/0011848, filed on July 6, 2007, in the name of John Thomas Stites, et al., U.S. Published Patent Application No. 2009/0011849, filed on July 6, 2007, in the name of John Thomas Stites, et al., U.S. Published Patent Application No. 2009/0011850, filed on July 6, 2007, in the name of John Thomas Stites, et al., and U.S. Published Patent Application No. 2009/0062029, filed on August 28, 2007, in the name of John Thomas Stites, et al ., all of which are incorporated herein by reference in their entireties.

[0034] As shown in FIGS. 2-8, the golf club head 102 includes a body member 108 having a face 112 and a hosel 109 extending from the body 108 for attachment of the shaft 104. For reference, the head 102 generally has a top 116, a bottom or sole 118, a heel 120 proximate the hosel 109, a toe 122 distal from the hosel 109, a front 124, and a back or rear 126. The shape and design of the head 102 may be partially dictated by the intended use of the device 100. The heel portion 120 is attached to and/or extends from the hosel 109 (e.g., as a unitary or integral one piece construction, as separate connected elements, etc.). In the embodiment shown in FIGS. 2-8, the body 108 and the hosel 109 are formed as a single, integral piece, such as by casting, forging, etc. The face 112 may also be formed of the same single, integral piece with the body 108 and the hosel 109. In another embodiment, the face 112, the body 108, and/or the hosel 109 may be formed of two or more separate pieces that are connected together by an integral joining technique or another joining technique. In other applications, such as for a different type of golf club, the head may be designed to have different dimensions and configurations.

[0035] The face 112 is located at the front 124 of the head 102, and has a ball striking surface 110 located thereon. The head 102 has a rear surface 111 located opposite the ball striking surface 110, which may be considered an inner surface of the face 112. The face 112 is defined by a plurality of peripheral edges, including a top edge 113, a bottom edge 115, a heel edge 117, and a toe edge 119. Additionally, the face 112 may be recognized as a portion of the head 102 that is intentionally smoothed and/or flattened to be configured for striking the ball, and the edges 113, 115, 117, 119 may be recognized as the borders or boundaries of this intentionally smoothed and/or flattened area.

[0036] The ball striking surface 110 is typically an outer surface of the face 112 configured to face a ball (not shown) in use, and is adapted to strike the ball when the device 100 is set in motion, such as by swinging. As shown, the ball striking surface 110 is relatively flat, occupying most of the face 112. The ball striking surface 110 may include grooves 121 (e.g., generally horizontal grooves 121 extending across the face 112 in the illustrated example) for the removal of water and grass from the face 112 during a ball strike. Of course, any number of grooves, desired groove patterns, and/or groove constructions may be provided (or even no groove pattern, if desired), including conventional groove patterns and/or constructions, without departing from this invention.

[0037] For reference purposes, the portion of the face 112 nearest the top face edge 113 and the heel 120 of the head 102 is referred to as the "high-heel area"; the portion of the face 112 nearest the top face edge 113 and toe 122 of the head 102 is referred to as the "high-toe area"; the portion of the face 112 nearest the bottom face edge 115 and heel 120 of the head 102 is referred to as the "low-heel area"; and the portion of the face 112 nearest the bottom face edge 115 and toe 122 of the head 102 is referred to as the "low-toe area". Conceptually, these areas may be recognized and referred to as quadrants of substantially equal size (and/or quadrants extending from a geometric center of the face 112), though not necessarily with symmetrical dimensions. The face 112 may include some curvature in the top to bottom and/or heel to toe directions (e.g., bulge and roll characteristics), as is known and is conventional in the art. In other embodiments, the ball striking surface 110 may occupy a different proportion of the face 112, or the body 108 may have multiple ball striking surfaces 110 thereon. As seen in the illustrative embodiments in FIGS. 5-7, the ball striking surface 110 is inclined (i.e., at a loft angle), to give the ball an appreciable degree of lift and spin when struck. In other illustrative embodiments, the ball striking surface 110 may have a different incline or loft angle, to affect the trajectory of the ball. Additionally, the face 112 may have a variable thickness and/or may have one or more internal or external inserts in some embodiments. It is understood that the face 112, the body 108, and/or the hosel 109 can be formed as a single piece or as separate pieces that are joined together.

[0038] The body 108 of the golf club head 102 may be constructed from a wide variety of different materials, including materials conventionally known and used in the art, such as steel, titanium, aluminum, tungsten, graphite, polymers, or composites, or combinations thereof. Also, if desired, the club head 102 may be made from any number of pieces (e.g., having a separate face plate, etc.) and/or by any construction technique, including, for example, casting, forging, welding, and/or other methods known and used in the art.

[0039] The ball striking device 100 may include a shaft 104 connected to or otherwise engaged with the ball striking head 102, as shown schematically in FIG. 1. The shaft 104 is adapted to be gripped by a user to swing the ball striking device 100 to strike the ball. The shaft 104 can be formed as a separate piece connected to the head 102, such as by connecting to the hosel 109, as shown in FIG. 1. In other illustrative embodiments, at l east a portion of the shaft 104 may be an integral piece with the head 102, and-'or the head 102 may not contain a hosel 109 or may contain an internal hosel structure. Still further embodiments are contemplated without departing from the scope of the invention. The shaft 104 may be constructed from one or more of a variety of materials, including metals, ceramics, polymers, composites, or wood. In some illustrative embodiments, the shaft 104, or at least portions thereof, may be constructed of a metal, such as stainless steel or titanium, or a composite, such as a carbon''graphite fiber-polymer composite. However, it is contemplated that the shaft 104 may be constructed of different materials without departing from the scope of the invention, including conventional materials that are known and used in the art. A grip element 105 may be positioned on the shaft 104 to provide a golfer with a slip resistant surface with which to grasp golf club shaft 104, as shown in FIG. 1. The grip element 105 may be attached to the shaft 104 in any desired manner, including in conventional manners known and used in the art (e.g., via adhesives or cements, threads or other mechanical connectors, swedging/swaging, etc.).

[0040] In one exemplary embodiment, shown in FIGS. 2-8, the body 108 of the head 102 includes a rear cavity 130 located behind the face 112, which is defined at least partially by the rear surface 111. As shown in FIGS. 2-8, the body 108 further includes a sole body member 131 extending rearward from the bottom edge 115 of the face 112 and defining a portion of the rear cavity 130. In another embodiment, the rear cavity 130 may also be partially defined by a rear wall extending upward from the rear of the sole member 131, such as in the embodiment of FIGS. 10-14A. The rear cavity 130 may also be partially defined by peripheral or perimeter walls 133 extending rearward from the peripheral edges of the face 112, including the top edge 113, the heel edge 117, and the toe edge 119 of the face 112. It is understood that the sole member 131, or a portion thereof, may be considered to be a peripheral wall 133 as defined herein. The peripheral walls 133 follow the curvilinear contour of the body 108, and form an opening to the rear cavity 130 defined by the peripheral walls 133, including the sole member 131. In this embodiment, the sole member 131 forms at least part of the sole 118 of the head 102, and the mass of the sole member 131 lowers the center of gravity of the head 102, which in turn, can produce greater loft on balls hit on the face 112. Additionally, the sole member 131 has an inner surface 134 that in part defines the rear cavity 130 and an outer surface 135 that forms at least a portion of a sole surface on the sole 118 of the head 102. In additional embodiments, such as the embodiments illustrated in FIGS.10- 18 A, the head 102 may have a differently configured sole member and/or a rear wall, or may not contain some of these components. For example, in the embodiment shown in FIGS. 10- 14 A, the head 202 has a rear wall 232 extending upward from the sole member 231, and in the embodiment shown in FIGS. 15-18A, the head 303 is a traditional blade-type iron configuration, and contains no rear cavity.

[0041] In general, the ball striking heads 102 according to the present invention contain features on the body 108 that influence the impact of a ball on the face 112. Such features include one or more compression channels 140 positioned on the body 108 of the head 102 that allow at least a portion of the body 108 to flex, produce a reactive force, and/or change the behavior or motion of the face 112, during impact of a ball on the face 112. In one embodiment, at least a portion of the compression channel(s) 140 may extend parallel or generally parallel to one of the adjacent edges of the face 112. In the golf club 100 shown in FIGS. 1-8, the head 102 includes a single channel 140 located on the sole 118 of the head 102. As described below, this channel 140 permits compression and flexing of the body 108 and the face 112 during impact on the face 112, and can also produce a reactive force that can be transferred to the ball. This illustrative embodiment 100 is described in greater detail below.

[0042] The golf club 100 shown in FIGS. 1-8 includes a compression channel 140 positioned on the sole 118 of the head 102. However, in other embodiments, the head 102 may have a channel 140 positioned differently on the head 102, such as on the top 116, the heel 120, and/or the toe 122. It is also understood that the head 102 may have more than one channel 140, or may have an annular channel extending around the entire head 102. As illustrated in FIG. 3, the channel 140 is elongated, extending between a first end 142 located proximate the heel 120 of the head 102 and a second end 144 located proximate the toe 122 of the head 102. The channel 140 has a boundary that is defined by a first side or edge 146 and a second side or edge 148 that extend between the ends 142, 144. In this embodiment, the channel 140 extends adjacent to and parallel or generally parallel to the bottom edge 115 of the face 112, and both the first and second ends 142, 144 are located on the sole 118. It is understood that if the bottom edge 115 of the face 112 has a greater degree of curvature when viewed from the bottom, the channel 140 may have a greater degree of curvature in order to remain generally parallel to the bottom edge 115. In another embodiment, one or both of the ends 142, 144 of the channel 140 may be located on the heel 120 and/or the toe 122 of the head 102, extending parallel or generally parallel to the heel and toe edges 117, 119 of the face 112. As seen in FIG. 3, the channel 140 is substantially symmetrically positioned on the head 102 in this embodiment. In other embodiments, the channel 140 may be oriented and/or positioned differently. For example, the channel 140 may be oriented to be parallel to a different edge of the face 112, or may not be parallel to any of the edges of the face 112. Additionally, in this embodiment, the channel 140 is straight or substantially straight along the direction of elongation, having substantially linear sides 146, 148. It is understood that the substantially linear sides 146, 148 of the channel 140 are straight when viewed from the bottom of the head 102, and may have some curvature due to the curvature of the sole surface 118 of the head 102.

[0043] The channel 140 is recessed inwardly with respect to the immediately adjacent surfaces of the head 102 that are in contact with the sides 146, 148 of the channel 140, as shown in FIGS. 5-8. The channel 140 in this embodiment has a trough 150 that is rounded and smoothly curvilinear in cross-section and sloping, depending side walls 152 extending from the trough 150 to the respective sides 146, 148 of the channel 140, as shown in FIGS. 5-6A. It is understood that the channel 140 may have a different cross-sectional shape or profile, such as the channels 140A-C illustrated in FIGS. 19-21, and the channel 140 may have a sharper and/or more polygonal shape in some embodiments. It is understood that, as used herein for reference purposes, the "length" of the channel 140 is measured in the direction of greatest elongation (i.e. between the ends 142, 144), the "width" of the channel 140 is measured transverse to the length along an outer surface of the head 102 (i.e. from front 124 to rear 126 in the head 102 in FIGS. 1- 8), and the "depth" of the channel 140 is measured from the trough 150 to the adjacent surfaces of the head 102 (i.e. from top 116 to sole 118 in the head 102 in FIGS. 1-8).

[0044] In the embodiment shown in FIGS. 2-8, the channel 140 is spaced from the bottom edge 115 of the face 112, with a flattened spacing portion 154 defined between the channel 140 and the bottom edge 115. The spacing portion 154 is located immediately adjacent the channel 140 and junctures with one of the side walls 152 of the channel 140 along the second side 148 of the channel 140, as shown in FIG. 5 A. In this embodiment, the spacing portion 154 is oriented at an acute (i.e. <90°) angle to the ball striking surface 110 and extends rearward from the bottom edge 115 of the face 112 to the channel 140. Force from an impact near the bottom edge 115 of the face 112 can be transferred to the channel 140 through the spacing portion 154, as described below. In other embodiments, the spacing portion 154 may be oriented at a right angle or an obtuse angle to the ball striking surface 110, or the flattened spacing portion 154 may be smaller than shown in FIGS. 5 and 5 A or absent entirely. For example, in one embodiment, the channel 140, or a portion thereof, may be positioned immediately adjacent the bottom edge 115 of the face 112, and in another embodiment, the channel 140, or a portion thereof, may be spaced much farther from the bottom edge 115 of the face 112, such as in the head 302 shown in FIGS. 15- 18 A.

[0045] Further, in the embodiment shown in FIGS. 2-8, the channel 140 extends inwardly into the sole member 131 of the head 102, in a direction that is parallel or generally parallel to the angle of the face 112, as illustrated in FIG. 5 A. In this embodiment, both of the side walls 152 of the channel 140 are parallel or generally parallel to the plane of the face 112, when viewed in cross-section, as also shown in FIG. 5 A. In other embodiments, one or both of the side walls 152 may not be parallel or generally parallel to the face 112, such as in the embodiments described below and shown in FIGS. 19-20. Additionally, in this embodiment, the depth of recession of the channel 140 is tapered, such that the depth of the channel 140 is greater at or around the center of the channel 140 than at the ends 142, 144 of the channel 140.

Accordingly, the lengths of the side wal ls 152 of the channel 140 are also tapered, such that the side walls 152 are longer at or around the center of the channel 140 than at the ends of the channel 140. The tapered depth of the channel 140 is illustrated in FIGS. 5-6A. As seen in FIGS. 5 and 5 A, in which the cross-section is taken at or around the center of the channel 140, the depth of the channel 140 is greater than the depth of the channel 140 in FIGS. 6 and 6 A, in which to cross-section is taken farther toward the toe 122 of the head 102. Further, in this embodiment, the depth of the channel 140 tapers smoothly from the center to the ends 142, 144 of the channel 140. In other words, the depth of the channel decreases from the center of the channel 140 toward the ends 142, 144, without any shoulders, breaks, or other sharp changes in contour of the trough 150. In another embodiment, the depth of the channel 140 may not be tapered, such as in the heads 202, 302 in FIGS. 10-18A, which are described below.

[0046] The compression channel 140 on the golf club 100 shown in FIGS. 1-8 can influence the impact of a ball 106 on the face 112 of the head 102. In one embodiment, the channel 140 can influence the impact by flexing and/or compressing in response to the impact on the face 112, and/or by exerting a reaction force on the face 112 during impact. FIGS. 7-8 illustrate an example of the head 102 of the golf club 100 of FIGS. 1-8 during and after an impact with a ball 106. For comparison, FIG. 9 illustrates a typical example of an existing ball striking head 10, having a face 12 and a body 8, during impact with a similar ball 106'. As seen in FIG. 7, when the ball 106 impacts the face 112 proximate the bottom edge 115 of the face 112, the bottom portion of the face 112 flexes inwardly. The rounded configuration of the trough 150 can assist in creating greater flexibility at the channel 140, as well as achieving more consistent and controlled flexing. Additionally, some of the impact force is transferred through the spacing portion 154 to the channel 140, causing the body 108 to flex at the channel 140, as also seen in FIG. 7. This flexing allows the bottom edge 115 of the face 112 to move rearwardly during a low impact, so that the impact between the relatively sharp and rigid bottom edge 115 and the ball 106 is minimized, resulting in higher ball velocity after impact. As shown in FIG. 9, when the ball 106' impacts a traditional head 12 proximate the bottom edge 15 of the face 12, the resul tant velocity of the ball 106' is lower, due in part to the contact between the bottom edge 15 and the ball 106'. A low ball velocity can have myriad negative effects, including robbing the shot of distance and/or accuracy. FIGS. 8-9 illustrate the difference in the velocity of the ball 106, 106' on impact that can be achieved in one embodiment of the invention. The flexing caused by the channel 140 also creates a more gradual impact with the ball 106 as compared to a traditional head 10 (FIG. 9), which results in a smaller degree of deformation of the ball 106 as compared to the traditional head 10. This smaller degree of deformation can result in greater impact efficiency and greater energy and velocity transfer to the ball 106 during impact. The more gradual impact created by the flexing also creates a longer impact time, which can also result in greater energy and velocity transfer to the ball 106 during impact. Further, as the compressed channel 140 expands to return to its initial shape (i.e. FIG. 8), a responsive or reactive force is exerted on the face 112, creating an increased "trampoline" effect, which can result in greater energy and velocity transfer to the ball 106 during impact. Still further, because the channel 140 extends toward the heel 120 and toe 122, the head 102 can achieve increased energy and velocity transfer to the ball 106 for impacts that are away from the center or traditional "sweet spot" of the face 112. It is understood that a channel 140 may be additionally or alternately incorporated into the top 116 and/or sides 120, 122 of the body 108 in order to produce similar effects for energy and/or velocity transfer.

[0047] It is understood that the head 102 may have one or more channels 140 in a different configuration in other embodiments. In one embodiment, the head 102 may have one or more channels on the top 116, the heel 120, and/or the toe 122, either instead of or in combination with a channel 140 on the sole 118. In a further embodiment, the head 102 may have one or more channels on an interior surface of the body 108, rather than on the exterior, such as within the rear cavity 130. In yet another embodiment, the head 102 may have two or more channels 140 spaced different distances from the face 112, and these channels 140 may "overlap" each other, creating a bellows-like effect in compression, as illustrated in FIGS. 29-30A. Still other embodiments are contemplated, including the embodiments described below and illustrated in FIGS. 10-21.

[0048] FIGS. 10-14A illustrate a second embodiment of a ball-striking device 200 having a ball striking head 202 in the form of an iron-type golf club. Many features of the club 200 and the head 202 shown in FIGS. 10-14A are similar to features described above with respect to the club 100 and the head 102 in FIGS. 1-8. Such similar features are referenced in FIGS. 10-14A with similar reference numerals, using the "2xx" series of reference numerals. Accordingly, some features of the club 200 and the head 202 in FIGS. 10-14A that are similar to the features of the club 100 and head 102 in FIGS. 1-8 may not be re-described or may be described in lesser detail below, and some features of the club 200 and the head 202 may be described only with respect to the differences from the club 100 and the head 102 in FIGS. 1-8. As such, certain drawing figures may be unnecessary and duplicative of other drawing figures herein.

[0049] The head 202 of FIGS. 10-14 A has a face 212, a body 208 connected to the face 212, and a hosel 209, similarly to the head 102 of FIGS. 1-8. The head 202 also has a sole member 231 extending rearward from the bottom of the face 212, as well as a rear cavity 230 defined by the sole member 231, peripheral walls 233, and the inner surface 211 of the face 212. In this embodiment, the body 208 also contains a rear wall 232 extending upward from the sole member

231 and across the entire rear 226 of the head 202. The peripheral walls 233 and the top edge of the rear wall 232 define a semi-circular external opening to the rear cavity 230. The rear wall

232 also partially defines the rear cavity 230 in this embodiment.

[0050] The head 202 of FIGS. 10-14A also has a channel 240 extending across the sole 218 of the head 202, similarly to the channel 140 in the embodiment of FIGS. 1-8. As similarly described above, the channel 240 is elongated, extending between a first end 242 located proximate the heel 220 of the head 202 and a second end 244 located proximate the toe 222 of the head 202. The channel 240 has a boundary that is defined by a first side 246 and a second side 248 that extend between the ends 242, 244, and extends adjacent to and parallel or generally parallel to the bottom edge 215 of the face 212, with both the first and second ends 242, 244 being located on the sole 218. Additionally, the channel 240 is straight or substantially straight along the direction of elongation, having substantially straight sides 246, 248, similarly to the channel 140 described above. The channel 240 in this embodiment has a trough 250 that is smoothly curvilinear in cross-section and sloping, depending side walls 252 extending from the trough 250 to the respective sides 246, 248 of the channel 240, as shown in FIGS. 13-14A, similarly to the channel 140 described above. Further, in the embodiment shown in FIGS. 10- 14A, the channel 240 is spaced from the bottom edge 215 of the face 212, with a flattened spacing portion 254 defined between the channel 240 and the bottom edge 215. The channel 240 extends inwardly into the sole member 231 of the head 202, in a direction that is parallel or generally parallel to the angle of the face 212, as illustrated in FIG. 13A. In the embodiment of FIGS. 10- 14 A, the depth of the channel 240 is not tapered and remains substantially constant over all or at lest a majority of the length of the channel 240, unlike the channel 140 in FIGS. 3- 8. In general, except for the differences described above, including the rear wall 232 and the configuration of the channel 240, the head 202 is otherwise similar to the head 102 in FIGS 1-8, and contains many similar features.

[0051] FIGS. 15-18A illustrate a third embodiment of a ball-striking device 300 having a ball striking head 302 in the form of an iron-type golf club. Many features of the club 300 and the head 302 shown in FIGS. 15-18A are similar to features described above with respect to the clubs 100, 200 and the heads 102, 202 in FIGS. 1-8 and 10- 14 A. Such similar features are referenced in FIGS. 15-18A with similar reference numerals, using the "3xx" series of reference numerals. Accordingly, some features of the club 300 and the head 302 in FIGS. 15-18A that are similar to the features of the clubs 100, 200 and heads 102, 202 in FIGS. 1-8 and 10-14A may not be re-described or may be described in lesser detail below, and some features of the club 300 and the head 302 may be described only with respect to the differences from the clubs 100, 200 and the heads 102, 202 in FIGS. 1-8 and 10- 14 A. As such, certain drawing figures may be unnecessary and duplicative of other drawing figures herein. [0052] The head 302 of FIGS. 15-18A has a face 312, a body 308 connected to the face 312, and a hosel 309, similarly to the head 102 of FIGS. 108. The head 302 in this embodiment is a blade-type iron head, and contains no rear cavity 132, 232 or rear wall 232, as in the heads 102, 202 described above. The body 308 does contain peripheral walls 233 extending rearward from the face 312, including a sole member 331 with a sole surface 318 thereon, and the inner surface

311 of the face 312 can be recognized as the surface at the rear 326 of the head 302.

[0053] The head 302 of FIGS. 15-18A also has a channel 340 extending across the sole 318 of the head 302, similarly to the channels 140, 240 in the embodiments of FIGS. 1-8 and 10-14A. As similarly described above, the channel 340 is elongated, extending between a first end 342 located proximate the heel 320 of the head 302 and a second end 344 located proximate the toe 322 of the head 302. The channel 340 has a boundary that is defined by a first side 346 and a second side 348 that extend between the ends 342, 344, and extends adjacent to the bottom edge 315 of the face 312, with both the first and second ends 342, 344 being located on the sole 318. In this embodiment, the channel 340 and the sides 346, 348 thereof are curvilinear in shape, and are not parallel or generally parallel to the bottom edge 115 of the face 112, differing from the channels 140, 240 described above. As shown in FIG. 16, the channel 340 curves rearwardly, such that the ends 342, 344 of the channel 340 are farther from the bottom edge 315 of the face

312 than the center of the channel 340. Additionally, the spacing portion 354 is larger near the ends 342, 344 of the channel 340 than at the center. This feature is also illustrated in FIGS. 17- 18 A, as the spacing portion 354 is shown to be larger in FIGS. 17 and 17 A, in which the cross- section is taken at or around the center of the channel 340, than in FIGS. 18 and 18 A, in which the cross-section is taken closer to the toe 322 of the head 302. The channel 340 in this embodiment has a trough 350 that is smoothly curvilinear in cross-section and sloping, depending side walls 352 extending from the trough 350 to the respective sides 346, 348 of the channel 340, as shown in FIGS. 17-18A, similarly to the channels 140, 240 described above. Further, in the embodiment shown in FIGS. 15-18A, the channel 340 is spaced from the bottom edge 315 of the face 312, with the flattened spacing portion 354 defined between the channel 340 and the bottom edge 315. The channel 340 extends inwardly into the sole member 331 of the head 302, in a direction that is parallel or generally parallel to the angle of the face 312, as illustrated in FIG. 17A. In the embodiment of FIGS. 15- 18 A, the depth of the channel 340 is not tapered and remains substanti ally constan t over all or at least a majority of the length of the channel 340, similar to the channel 240 in FIGS. 11-14A and unlike the channel 140 in FIGS. 3- 8. In general, except for the differences described above, including the blade-type configuration, the lack of the rear cavity, and the configuration of the channel 340, the head 302 is otherwise similar to the head 102 in FIGS 1-8, and contains many similar features.

[0054] FIGS. 23-27A illustrate a fourth embodiment of a ball-striking device 400 having a bal l striking head 402 in the form of an iron-type golf club. Many features of the club 400 and the head 402 shown in FIGS. 23-27A are similar to features described above with respect to the club 100 and the head 102 in FIGS. 1-8. Such similar features are referenced in FIGS. 23 -27 A with similar reference numerals, using the "4xx" series of reference numerals. Accordingly, some features of the club 400 and the head 402 in FIGS. 23 -27 A that are similar to the features of the club 100 and head 102 in FIGS. 1-8 may not be re-described or may be described in lesser detail below, and some features of the club 400 and the head 402 may be described only with respect to the differences from the club 100 and the head 102 in FIGS. 1 -8. As such, certain drawing figures may be unnecessary and duplicative of other drawing figures herein.

[0055] The head 402 ofFIGS. 23-27A has a face 412, a body 408 connected to the face 412, and a hosel 409, similarly to the head 102 of FIGS. 1-8. The head 402 also has a sole member 431 extending rearward from the bottom of the face 412, as well as a rear cavity 430 defined by the sole member 431, peripheral walls 433, and the inner surface 411 of the face 412. In generally, the shape and configuration of the face 412 and the body 408 of this embodiment are substantially the same as those of the head 102 ofFIGS. 1-8.

[0056] The head 402 ofFIGS. 23 -27 A also has two channels 440 extending across the sole 418 of the head 402. The channels 440 have a general shape and cross-sectional configuration that are similar to each other and to the channel 240 in the embodiment of FIGS. 10- 14 A. As similarly described above, each of the channels 440 is elongated, extending between a first end 442 located proximate the heel 420 of the head 402 and a second end 444 located proximate the toe 422 of the head 402. Each channel 440 has a boundary that is defined by a first side 446 and a second side 448 that extend between the ends 442, 444, and extends adjacent to and parallel or generally parallel to the bottom edge 415 of the face 412, with both the first and second ends 442, 444 being located on the sole 418. Additionally, each channel 440 is straight or substantially straight along the direction of elongation, having substantially straight sides 446, 448, similarly to the channel 140 described above. The channels 440 in this embodiment each have a trough 450 that is smoothly curvilinear in cross-section and sloping, depending side walls 452 extending from the trough 450 to the respective sides 446, 448 of the channel 440, as shown in FIGS. 27 and 27A, similarly to the channels 140, 240 described above. Further, in the embodiment shown in FIGS. 23-27 A, the channels 440 are each spaced from the bottom edge 415 of the face 412, with the flattened spacing portion 454 defined between each channel 440 and the bottom edge 415. The channels 440 each extend inwardly into the sole member 431 of the head 402, in a direction that is parallel or generally parallel to the angle of the face 412, as illustrated in FIG. 27A. In the embodiment of FIGS. 23-27 A, the depth of each channel 440 is not tapered and remains substan tially constant over all or at least a majority of the length of the channel 440, similar to the channel 240 in FIGS. 11-14A. In other embodiments, the channels 440 may be configured differently from each other, such as by having different shapes, cross- sectional profiles, depths, widths, lengths, etc.

[0057] The channels 440 in FIGS. 23-27A extend toward each other along a common axis of elongation and are spaced approximately equal distances from the bottom edge 415 of the face 412, such that the channels 440 have a virtual intersection point if the channels 440 extended infinitely. It is understood that the channels 440 having a common axis of elongation does not necessarily imply that the channels 440 are parallel to each other. However, in this embodiment, the channels 440 stop short of the center of the sole 418, such that a gap 462 is defined between the ends 444, 442 of the channels 440. The gap 462 is positioned to be substantially centered along a centerline of the sol e 418 that extends from the front 424 to the rear 426 of the head 402, which is often the lowest portion of the sole 418. The head 402 in FIGS. 23-27A provides increased loft, as well as increased energy and/or velocity transfer, on a ball 106 struck by the head 402, as similarly described above, and in particular on balls 106 struck toward the heel 420 or toe 422 of the sweet spot of the face 402. Additionally, the smooth portion of the sole 118 located in the gap 462 reduces any drag or other interference between the head 402 and the playing surface that may result from hitting a ball 106 sitting directly on the playing surface. In general, except for the differences described above, including the configurations of the channels 440, the head 402 is otherwise similar to the head 102 in FIGS 1-8, and contains many similar features. [0058] The heads 202, 302, 402 in the embodiments illustrated in FIGS. 10-18A and 23-27A can influence the impact of a ball 106 on the face 212, et seq. of the head 202, et seq. in a similar manner to that described above with respect to the head 102 in FIGS. 1-8. The head 202, et seq. influences the impact of the ball 106 by the channel 240, et seq. flexing and/or compressing in response to the impact on the face 212, et seq., and/or by exerting a reaction force on the face 212, et seq. during impact. As described above, this compression and/or flexing of the channel 240, et seq. can produce greater energy and/or velocity transfer to the ball 106 during impact, including during mis-hit impacts near the bottom edge 215, et seq. of the face 212, et seq.. These benefits may also be realized for impacts that are away from the center or traditional "sweet spot" of the face 212, et seq., as also described above.

[0059] FIGS. 19-22 illustrate additional embodiments of channels 140A-D that can be incorporated into heads 102, et seq. as described above and shown in FIGS. 1-18A and 23-27 A, as well as the heads 502, 602 described below and shown in FIGS. 23-30A. FIG. 19 illustrates an embodiment of a channel 140 A in which the channel 140 A extends inwardly into the sole member 131 A in a direction transverse to the face 112A. In this embodiment, both side walls 152A of the channel 140 A are angled transversely to the face 112A and are parallel or generally parallel to each other. Additionally, the trough 150 A of the channel 140 A is substantially flat, giving the channel 140 A a polygonal square or rectangular shape in cross-section. This configuration differs from the configuration in FIGS. 1-8, in which the channel 140 and the side walls 152 are parallel or generally parallel to the face 112, and the trough 150 is smoothly curvilinear.

[0060] FIG. 20 illustrates an embodiment of a channel 140B in which the channel 140B has a polygonal triangular shape in cross-section and an outwardly tapered configuration. In this embodiment, the channel 140B has two side walls 152B that are arranged at oblique angles to each other, forming an angular trough 150B. One of the side walls 152B is arranged at a transverse angle to the face 112B, and the side wall 152B most proximate the face 112B is generally parallel to the face 112B. In this configuration, the channel 140B is tapered so that the width of the channel 140B is greater proximate the sides 146B, 148B than at the trough 150B. This configuration differs from the configuration in FIGS. 1-8, in which the channel 140 and the side walls 152 are parallel or generally parallel to the face 112 and to each other, the trough 150 is smoothly curvilinear, and th e width of the channel 140 is substanti ally con stan t.

[0061] FIG . 21 illustrates an embodiment of a channel 140C in which the channel 140C has an irregular shape in cross-section and an inwardly tapered configuration, in this embodiment, the channel 140C has two side walls 152C that are arranged at oblique angles to each other. The side wall 150C most distant from the face 112C is relatively flat and parallel or generally parallel to the face, and the side wall 152C most proximate the face 112C is has a curvilinear cross section. In this configuration, the channel 140C is tapered so that the width of the channel 140C is greater proximate the trough 150C than at the sides 146C, 148C. This configuration differs from the configuration in FIGS. 1-8, in which the channel 140 and the side walls 152 are parallel or generally parallel to the face 112 and to each other, both side walls 152 are flat, and the width of the channel 140 is substantially constant.

[0062] FIG. 22 illustrates an embodiment of a channel 140D that is configured with the same size, shape, and contours to the channel 140 in FIGS. 3-8. In this embodiment, the channel 140D contains an insert 160D filling at least a portion of the channel 140D. The insert 160D can be made of a flexible material, such as a polyurethane rubber or other polymer material, or another material with sufficient flexibility and/or resiliency. The insert 160D can add additional resiliency and response force when the channel 140D flexes upon impact of a ball on the face 112D. This insert 160D can also assist in reducing or eliminating drag or other forces between the sole 118D of the head 102 and the playing surface in use. Accordingly, forces on the sole 118D which may slow the speed of the head 102, alter the orientation or position of the head 102, and/or otherwise affect the swinging motion of the head 102 can be reduced appreciably. In one embodiment, the insert 160D may fi ll the channel 140D over most or all of the length of the channel 140D. In another embodiment, the insert 160D may fill only a portion of the channel 140D, such as the area around the center of the sole 118D and/or across the lowest point on the sole 118D, as shown in FIG. 28 and described below. In a further embodiment, the insert 160D may contain a rigid outer member (not shown), which can assist in reducing the drag and other forces, by providing a smooth, rigid surface that can glide along the playing surface more easily. Additionally, the fact that the outer surface of the insert 160D is substantially flush with the adjacent surfaces of the body 108D creates a smoother surface that is less prone to creation of drag forces during contact with the playing surface. Different embodiments of inserts 160D that can be incorporated for use in channels 140, et seq. as described herein are shown and described in U.S. Patent Application Serial No. 13/015,264, filed January 27, 2011, which is incorporated by reference herein in its entirety and made part hereof. An insert 160D as described above can be mounted in the channel 140D in many different configurations and methods, including any configurations and methods shown and/or described in the aforementioned U.S. Patent

Application No. 13/015,264. For example, the insert 160D can be poured into the channel 140D in a flowable form, allowing the material of the insert 160D to solidify or harden within the channel 140D. As another example, the insert 160D and the channel 140D may have some cooperative mounting structure, such as a peg-and-aperture arrangement. In a further

embodiment, an adhesive or other such agent may be used.

[0063] FIG. 28 illustrates a fifth embodiment of a ball-striking head 502 in the form of an iron-type golf club head. The head 502 shown in FIG. 28 is identical to the head 102 shown in FIGS. 1-8, and similar features of the head 502 are referenced in FIG. 28 with similar reference numerals, using the "5xx" series of reference numerals. Accordingly, some features of the head 502 in FIG. 28 that are similar to the features of the head 102 in FIGS. 1-8 may not be re- described or may be described in lesser detail below, and some features of the head 502 may be described only with respect to the differences from the head 102 in FIGS. 1-8. As such, certain drawing figures may be unnecessary and duplicative of other drawing figures herein.

[0064] The head 502 of FIG. 28 has an insert 560 positioned within the channel 540, similarly to the insert 160D described above and shown in FIG. 22. The insert 560 in this embodiment extends only a portion of the length of the channel 540 proximate the centerline of the sole 118, and the ends of the insert 560 are spaced from the ends 542, 544 of the channel 540. Accordingly, in this embodiment, the channel 540 extends the same length as the channel 540 in FIGS. 2-8, and also retains the benefit of creating a substantially smooth surface 518 proximate the center of the sole 518, which is also typically the lowest portion of the sole 518. As similarly described above with respect to the head 402 in FIGS. 23-27A, the substantially smooth sole surface 518 can reduce any drag or other interference between the head 402 and the playing surface that may result from hitting a ball 106 sitting directly on the playing surface.

Additionally, the insert 560 may add resiliency to the channel 560 and may increase the response force generated by the channel 540 when re-expanding after flexing during impact, which can result in greater energy and/or velocity transfer. The insert 560 may be configured and mounted in any configuration described above with respect to the insert 160D in FIG. 22, including those described and shown in the aforementioned U.S. Patent Application No. 13/015,264. It is understood that if the channel 540 has a tapered depth, as in the channel 140 described above and shown in FIGS. 3-6, or a tapered width, as in the channels 140B-C described above and shown in FIGS. 20-21, the insert 560 may have a correspondingly tapered thickness or width, respectively.

[0065] FIGS. 29-30A illustrate a fifth embodiment of a ball-striking head 602 in the form of an iron-type golf club head. The head 602 shown in FIGS. 29-30A is identical in shape and configuration to the head 102 shown in FIGS. 1-8, except for the inclusion of the multiple channels 602A-B as described below. Thus, similar features of the head 602 are referenced in FIGS. 29-30A with similar reference numerals as in FIGS. 1-8, using the "6xx" series of reference numerals. Accordingly, some features of the head 602 in FIGS. 29-30A that are similar to the features of the head 102 in FIGS. 1-8 may not be re-described or may be described in lesser detail below, and some features of the head 602 may be described only with respect to the differences from the head 102 in FIGS. 1-8. As such, certain drawing figures may be unnecessary and duplicative of other drawing figures herein.

[0066] The head 602 of FIGS. 29-30A includes a plurality of channels 640A-B positioned on the sole 518 of the head 502. As seen in FIG. 29, the head 602 includes a first channel 640A positioned proximate the bottom edge 615 of the face 612 and a second channel 640B positioned rearward of the first channel 640A and spaced from the first channel 640A. In this embodiment, the channels 640A-B are parallel and adjacent to each other, and are arranged in series. In other embodiments, the head 602 may contain multiple channels in another arrangement or

configuration. The channels 640A-B in this embodiment each have a general shape and cross- sectional configuration that are similar to each other and similar to the channel 140 in the embodiment of FIGS. 1-8. As similarly described above, each of the channels 640A-B is elongated, extending between a first end 642 located proximate the heel 620 of the head 602 and a second end 644 located proximate the toe 622 of the head 602. Each channel 640A-B has a boundary that is defined by a first side 646 and a second side 648 that extend between the ends 642, 644, and extends paral lel or general ly paral lel to the bottom edge 615 of the face 612, with both the first and second ends 642, 644 being located on the sole 618. Additionally, each channel 640 is straight or substantially straight along the direction of elongation, having substantially straight sides 646, 648, similarly to the channel 140 described above.

[0067] The channels 640 in this embodiment each have a trough 650 that is smoothly curvilinear in cross-section and sloping, depending side walls 652 extending from the trough 650 to the respective sides 646, 648 of the channel 640, as shown in FIGS. 30 and 3 O A, similarly to the channels 140, 240 described above. Further, in the embodiment shown in FIGS. 29-30A, the channels 640 A-B are each spaced from the bottom edge 615 of the face 612, with a first flattened spacing portion 654 A defined between the first channel 640 A and the bottom edge 615 and a second flattened spacing portion 654B defined between the first and second channels 640A-B. The channels 640A-B each extend inwardly into the sole member 631 of the head 602, in a direction that is parallel or generally parallel to the angle of the face 612, as illustrated in FIG. 30A. In the embodiment of FIGS. 29-30A, the depth of each channel 640A-B is tapered in the same way as the channel 140 in FIGS. 3-8. In other embodiments, the head 602 may have two or more channels arranged in series, with at least one of the channels being configured differently than at least one other of the channels, such as by having a different shape, cross-sectional profile, depth, width, length, etc.

[0068] The channels 640A-B in this embodiment can provide increased loft and increased energy and/or velocity transfer on a ball 106 struck by the head 602, as similarly described above. Additionally, the parallel and adjacent channels 640A-B arranged in series can also produce a bel lows-like effect, wh ich may enhance the performance of these functions. Further, the channels 640A-B result in a greater proportion of the mass of the head 602 being removed as compared to a head having only a single such channel, which can shift the weight distribution of the head 602 toward the rear 626 of the head 602 and increase the moment of inertia of the head 602.

[0069] Several different embodiments have been described above, including the iron-type golf clubs 100, 200, 300 and heads 102, 202, 302, 402, 502, 602. It is understood that any of the features of these various embodiments may be combined and/or interchanged. For example, as described above, various different combinations of club heads 102, et seq. with differently configured channels 140, et seq. may be used, including the configurations described herein, variations or combinations of such configurations, or other configurations. In further

embodiments, at least some of the features described herein can be used in connection with other configurations of iron-type clubs, or with other non-iron-type clubs.

[0070] Heads 102, et seq. incorporating the features disclosed herein may be used as a ball striking device or a part thereof. For example, a golf club 100 as shown in FIG. 1 may be manufactured by attaching a shaft or handle 104 to a head that is provided, such as the head 102 as described above. "Providing" the head, as used herein, refers broadly to making an article available or accessible for future actions to be performed on the article, and does not connote that the party providing the article has manufactured, produced, or supplied the article or that the party providing the article has ownership or control of the article. Manufacturing the head 102, et seq. may also include forming one or more channels 140, et seq. in the head. The channel(s) 140, et seq. can be formed in one of many different manners, including being formed along with the head 102, et seq. or body 108, et seq., such as in a casting/molding or forging process, or being formed in a post-manufacture process, such as cutting, milling, machining, etc. In other embodiments, different types of ball striking devices can be manufactured according to the principles described herein. Additionally, the head 102, et seq., golf club 100, et seq., or other ball striking device may be fitted or customized for a person by custom fitting, which may include choosing a head 102, et seq. having a channel 140, et seq. with one or more particular characteristics that are suited for a particular golfer, or forming such a channel 140, et seq. in the head 102, et seq. Various other different configurations are possible, and various other club heads may be designed for various performance characteristics.

[0071] The ball stri king devices and heads therefor as described herein provide many benefits and advantages over existing products. For example, as described above, the flexing of the sole 118 at the channel 140 can create greater energy and/or velocity transfer to the ball 106 on impacts, including impacts where the ball hits away from the center or traditional sweet spot of the face, such as too close to the bottom edge 115 of the face 112 and/or too close to the heel 120 or toe 122 of the face 112. As another example, the addition of the channel 140 removes mass from the body 108 proximate the face 112, which shifts the center of gravity of the head 102 rearward and increases the moment of inertia of the head 102. As a further example, any material lost from the forward areas of the club head 102 created by the presence of the channel can be strategically located elsewhere on the club head 102 as desired, while maintaining a proper total weight of the club head 102. For instance, additional weight can be added to various portions of the club head including the heel 120, the toe 122, the rear 126, etc. Further benefits and advantages are readily recognizable to those skilled in the art.

[0072] While the invention has been described with respect to specific examples including presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described systems and methods. Thus, the spirit and scope of the invention should be construed broadly as set forth in the appended claims.