Improved Sporting Goods

Abstract

Aerodynamically improved sporting goods are provided, including golf clubs. The golf club head includes a plurality of dimples configured to reduce drag on the head when swung by a user, and a chamber defined in the head that includes one or more weights movable within the chamber to adjust the balance of the golf club head. The movable weights allow adjustments to be made to compensate for changes in the characteristics of the golf club due to increased aerodynamic efficiency.

Description

[Technical Field]

[0001] The present invention relates to improved sporting equipment, including clubs, rackets, bats and sticks, and helmets, such as motorcycle and bicycle helmets. In particular, although not exclusively, the present invention relates to improved golf clubs. [Background technology]

[0002] When swinging a golf club, the club head moves through the air at a significant speed and, as a result, experiences significant wind resistance, particularly drag forces acting in a direction opposite to the movement of the golf club head, ultimately slowing down the speed of the swing.

[0003] For the average male golfer, the driver head can travel up to 95 mph / 152 km / h, and for a professional long-driver, the head can travel up to 150 mph / 241 km / h. At these speeds, wind resistance creates significant resistance to the golfer's body, which can lead to injury. Additionally, drag reduces the speed of the club head, which equates to a reduction in the distance the ball travels.

[0004] Many attempts have been made to improve the airflow around golf club heads, thereby reducing the drag of the head during a swing. Initially, golf club heads were given aerodynamic shapes, often teardrop-shaped in cross section. The problem with such golf club heads was that they still created significant wind resistance.

[0005] Recently, cavities (cutouts) have been used to break up the vortices that form behind the golf club head and reduce drag. The cavities (cutouts) are generally a few centimeters in size and can take on a variety of shapes. The problem with using such cavities (cutouts) is that, due to their size, they significantly alter the characteristics of the golf club head, including changing the shape and overall volume of the club head, and reduce the visual appeal of the golf club.

[0006] A further problem with the use of such voids is that the United States Golf Association (USGA) is very strict regarding the presence of voids in golf club heads, so the voids cannot be placed in a desired location from a drag standpoint while still maintaining compliance with USGA standards.

[0007] A further problem with golf clubs is that the drag of the head during a swing causes the club to bend, which is beneficial when striking the ball. Significantly reducing the drag of a golf club head changes the characteristics of the golf club, such as how the club bends, which in turn affects the way the head strikes the ball. Thus, changing the aerodynamics of a golf club head is complex and affects the entire golf club.

[0008] Yet another problem with prior art golf clubs is that they generally have a fixed construction and are not easily adaptable. As a result, fitting clinics are offered where professionals assist golfers in selecting and fitting a set of clubs to their needs. While fitting clinics are excellent at helping golfers select a set of clubs, the clubs typically remain stationary after fitting, even as the golfer's skill, swing speed, and needs change.

[0009] Many attempts have been made to alter the aerodynamics of other types of sporting equipment, such as clubs, rackets, bats, and sticks. For example, tennis, squash, and badminton rackets, baseball bats, and hockey sticks are swung through the air at high speeds and face similar problems to those described above for golf clubs.

[0010] Similarly, helmets face similar problems because they often travel through the air at high speeds. A further problem with helmets is that the desire to have a cool and comfortable helmet is in direct conflict with aerodynamics. Furthermore, helmets with high airflow (such as bicycle helmets with large holes) are not suitable for use in the rain because, in addition to being poor aerodynamics, they also cause the rider's head to get wet. While generally closed helmets, such as motorcycle helmets, may be better at keeping out rain, they often have problems with helmet ventilation and visor fogging, creating dangerous situations for the rider.

[0011] Thus, there is a clear need for improved sporting equipment such as clubs, rackets, bats, sticks, helmets, and the like.

[0012] Where a prior art publication is referred to herein, it is to be expressly understood that this reference is not an admission that the publication forms part of the general knowledge in the art in Australia or any other country. Summary of the Invention

[0013] The present invention is directed to sporting goods, such as clubs, rackets, bats, sticks, and helmets, which may at least partially overcome at least one of the above-mentioned drawbacks or may provide consumers with a useful or commercial choice.

[0014] In view of the foregoing, the present invention resides in one form broadly in a golf club including a head, the head comprising: a plurality of dimples configured to reduce drag on the head when swung by a user; and The head includes a chamber defined in the head, the chamber including one or more weights movable within the chamber to adjust the balance of the golf club head.

[0015] Advantageously, the use of dimples significantly improves the aerodynamic efficiency of the golf club head, thereby improving the golf club. The movable weight allows for adjustments to be made to compensate for changes in the characteristics of the golf club that accompany the increased aerodynamic efficiency.

[0016] Preferably, the dimples include spherical dimples. Alternatively, the dimples include hexagonal dimples.

[0017] The dimples may be between about 0.01 mm and 1.5 mm deep and between about 0.5 mm and 3 mm in diameter.

[0018] Preferably, the dimple does not include a gripping edge at the junction between the surface of the body and the dimple. The dimple may extend into the body at an angle of less than about 45 degrees.

[0019] One or more of the dimples may be at least partially disposed on the striking face of the golf club head, but may be configured so as not to affect a golf ball struck by the striking face.

[0020] The striking face may include a plurality of elongated grooves, with at least some of the dimples located between adjacent grooves.

[0021] The dimples may include first dimples and second dimples, the first dimples being substantially uniform in size and shape, the second dimples being substantially uniform in size and shape, and the first dimples being different from the second dimples in at least one of size and shape.

[0022] At least some of the dimples may be arranged in rows, the rows being parallel or perpendicular to the edge of the golf club.

[0023] At least 50% of the head surface may be covered with dimples.

[0024] The weight may be adjustable in position from the outside of the golf club head.

[0025] The chamber may be elongated in a direction substantially perpendicular to the striking face of the golf club. The chamber may be substantially uniform in cross section.

[0026] A golf club head may include one or more weights biased against the front of the club using a biasing member such as a spring.

[0027] When the golf club strikes the ball, one or more weights may be able to move partially within the chamber to produce a pinging sound.

[0028] The golf club head may include a threaded rod configured to engage a weight within the chamber, thereby allowing the weight to move along the length of the chamber through rotation of the threaded rod.

[0029] The chamber may comprise a cylindrical chamber and the one or more weights may be disk-shaped.

[0030] The chamber may be centrally located in the golf club head. The chamber may be supported by one or more arms and an inner surface of the golf club head.

[0031] The golf club head may include a channel defined in a surface of the golf club head, where at least a subset of the dimples are defined in the channel.

[0032] The channel may be defined in the crown of the golf club head.

[0033] The channel may be tapered.

[0034] The channel may include multiple channels. The channels may be in parallel.

[0035] The dimples may create a boundary layer of air that allows turbulent, smooth-flowing air to travel over. The dimples may also reduce the size of the wake behind the body when swung, thereby reducing overall drag.

[0036] The dimples may be located on one or more of the sole, heel, face, hosel, crown, toe, top, and back of the golf club or head for the golf club.

[0037] In another form, the invention resides broadly in a helmet including one or more air flow paths from an interior of the helmet to an exterior of the helmet, and a channel configured to direct air flow to create a low pressure adjacent the air flow path, thereby drawing air out of the helmet through the air flow path.

[0038] Advantageously, the use of channels to draw air from the helmet allows for ventilation while providing aerodynamic efficiency.

[0039] The channel may include an opening at the front of the helmet and an exit at the rear of the helmet.

[0040] The channel may include a plurality of dimples at the opening.The channel may include a plurality of dimples along the length of the channel.

[0041] The channel may be at least partially enclosed. The channel may extend across the top of the helmet.

[0042] The channel may include a narrow central portion configured to create a low pressure area. The channel may be configured to create a Venturi effect, thereby drawing air from the helmet.

[0043] The channel may include a plurality of covers configured to partially cover the air flow passage. The covers may include reverse cowl-type covers. The covers may be adapted to prevent rain from entering the air flow passage. The covers may be positioned over the openings of the air flow passage.

[0044] The air channels may be arranged in rows.

[0045] The air flow path may include a tubular passage. The air flow path may include a channel that opens to the inside of the helmet.

[0046] The air flow channels may be configured to extract air from around the helmet visor, which in turn may circulate air around the inner surface of the visor, thereby reducing fogging of the visor.

[0047] The channel may include an adjustable cover configured to allow adjustment of the amount of air flow into the channel.

[0048] In yet another form, the invention resides broadly in a sporting item adapted to be swung by a user, the sporting item including a body including one or more channels and a plurality of dimples defined within the channels, the dimples and channels configured to reduce drag on the body when swung by a user.

[0049] Advantageously, the dimples and channels reduce drag without substantially changing the shape of the sports equipment, resulting in less resistance being presented to the player's body at a particular swing speed, thereby reducing the risk of injury or allowing for increased swing speed.

[0050] The channels may extend in the direction of airflow in use. The channels may include a central channel that extends in the direction of airflow in use and one or more other channels that do not extend in the direction of airflow in use.

[0051] Preferably, the sporting equipment includes a handle. Preferably, the sporting equipment includes a striking surface configured to strike a ball or other item (e.g., a puck).

[0052] Preferably, the sporting goods include a golf club. The body may include a golf club head.

[0053] The dimples can be located on a striking surface of a sporting item. The dimples can be configured to have no effect on an item (e.g., a ball or a puck) struck by the striking surface. In the case of a golf club, the dimples on the striking surface can be configured to have no effect on the golf ball (e.g., not impart any significant additional spin to the golf ball).

[0054] In the case of a golf club, the striking face may include a plurality of elongated grooves, and at least some of the dimples may be disposed between adjacent grooves. The grooves may be parallel, and at least some of the dimples may form rows that are parallel to the grooves.

[0055] The sporting goods may include a chamber including one or more weights movable within the chamber to adjust the balance of the sporting goods. The chamber may include an interior chamber. The chamber may be defined by a handle of the sporting goods.

[0056] The dimples may include first dimples and second dimples, the first dimples being substantially uniform in size and shape, the second dimples being substantially uniform in size and shape, and the first dimples being different from the second dimples in at least one of size and shape.

[0057] The first dimple can be disposed on a first surface of the sporting goods, and the second dimple can be disposed on a second surface of the sporting goods. The first surface can include a striking surface of the sporting goods, and the second surface can be a non-striking surface of the sporting goods.

[0058] The body of the sporting goods, or portions thereof, may be formed of metal. The dimples may be cast into the body. The dimples may be machined, pressed, or stamped into the body. The body may be 3D printed.

[0059] The body of the sporting goods, or portions thereof, may be formed from plastic, polycarbonate, composite material, or any other suitable material.

[0060] The body can be formed in one piece, or it can be formed from two or more components. For example, the body can be formed of metal with a thin polycarbonate sleeve covering a portion of it, with at least some of the surface features defined in the polycarbonate sleeve.

[0061] In yet another form, the invention resides broadly in a cover for attachment to and covering at least a portion of a golf club head to enhance the aerodynamic efficiency of the golf club, the cover including dimples defined on an outer surface thereof.

[0062] The cover may be adapted to cover at least one face of the golf club.

[0063] The cover can be clipped onto the golf club. The cover can be adhered to the golf club using an adhesive.

[0064] Any of the features described herein may be combined in any combination with any one or more of the other features described herein within the scope of the present invention.

[0065] The reference to prior art herein is not intended to be, and should not be construed as, an acknowledgment or any form of suggestion that the prior art forms part of the common general knowledge.

[0066] Various embodiments of the present invention are described below with reference to the following drawings. [Brief explanation of the drawings]

[0067] [Figure 1] 1 illustrates a top view of a golf club head according to an embodiment of the present invention. [Figure 2] 2 shows a front view of the head of the golf club of FIG. 1. [Figure 3] 2 illustrates a cutaway view of the bottom of the golf club head of FIG. 1 in accordance with an embodiment of the present invention. [Figure 4] 2 shows a front cutaway view of the golf club head of FIG. 1. [Figure 5] 10 illustrates a cutaway view of the bottom of a golf club head according to an alternative embodiment of the present invention. [Figure 6] 1 illustrates a top view of a golf club head according to an embodiment of the present invention. [Figure 7] 7 illustrates a front cutaway view of the golf club head of FIG. 6 in accordance with an embodiment of the present invention. [Figure 8] 1 illustrates a top view of a golf club head according to an embodiment of the present invention. [Figure 9] 1 illustrates a top view of a golf club head according to an embodiment of the present invention. [Figure 10] 1 illustrates a top view of a golf club head according to an embodiment of the present invention. [Figure 11] 11 shows a front view of the head of FIG. 10. [Figure 12] 1 illustrates a top view of a golf club head according to an embodiment of the present invention. [Figure 13] 1 illustrates a top view of a golf club head according to an embodiment of the present invention. [Figure 14] 14 shows a bottom view of the head of FIG. 13. [Figure 15] 1 illustrates a top view of a golf club head according to an embodiment of the present invention. [Figure 16]FIG. 16 shows a bottom view of the head of FIG. 15, showing the weight in a forward position. [Figure 17] FIG. 16 shows a bottom view of the head of FIG. 15, showing the weight in a rearward position. [Figure 18] 1 illustrates a perspective view of a cutaway of a golf club head according to an embodiment of the present invention. [Figure 19] 1 illustrates a perspective view of a cutaway of a golf club head according to an embodiment of the present invention. [Figure 20] A golf club head is shown that includes dimples over the entire surface to demonstrate how the dimples improve the aerodynamics of the golf club. [Figure 21] 1 illustrates an exploded side view of a golf club head including a head portion and a dimpled cover according to an embodiment of the present invention. [Figure 22] 22 shows a cross-sectional view of the dimpled cover of FIG. 21. [Figure 23] 22 shows a front view of the golf club head of FIG. 21 with the cover installed. [Figure 24] 1 illustrates a side, partially exploded view of a golf club head with a head portion and a dimpled cover separated, according to an embodiment of the present invention. [Figure 25] 1 shows a front view of a motorcycle helmet according to an embodiment of the present invention. [Figure 26] 26 shows a side view of the motorcycle helmet of FIG. 25. [Figure 27] 26 shows a rear view of the motorcycle helmet of FIG. 25. [Figure 28] 26 shows a top view of the helmet of FIG. 25. [Figure 29] 29 shows a side cross-sectional view of the helmet through AA in FIG. 28. [Figure 30] 26 shows a cross-sectional front view of the helmet of FIG. 25, illustrating two different types of airflow paths through the helmet. [Figure 31] 29 shows a cross-sectional side view of the helmet of FIG. 25, showing area B of FIG. 29. [Figure 32] 32 shows a cross-sectional side view of the helmet of FIG. 25 showing area C of FIG. 31. [Figure 33] 26 shows a cross-sectional side view of the helmet of FIG. 25 showing use, according to an embodiment of the present invention. [Figure 34] 1 shows a side view of a helmet with a shutter in a closed position according to an embodiment of the present invention. [Figure 35] FIG. 1 shows a side view of the helmet with the shutter in the open position. [Figure 36] 1 illustrates a tennis racket according to an embodiment of the present invention. [Figure 37] This shows the inner surface of area D of the tennis racket in Figure 36. [Figure 38] This shows the front view of area D of the tennis racket in Figure 36. [Figure 39] This shows the outer surface of area D of the tennis racket in Figure 36. [Figure 40] 1 illustrates a front view of a tennis racket according to an embodiment of the present invention. [Figure 41] Area E of the tennis racket in FIG. 40 is shown. [Figure 42] 41 shows an end view of the handle of the racket of FIG. 40. [Figure 43] 40. A cross-sectional view from the handle of the racket of FIG. 40 to the FF of FIG. 41 is shown. [Figure 44] 1 illustrates a front view of a tennis racket with a weight assembly according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0068] Preferred features, embodiments, and variations of the invention can be discerned from the following detailed description, which provides sufficient information for one skilled in the art to practice the invention, and is not to be construed as limiting the scope of the preceding Summary of Invention in any way.

[0069] Figure 1 shows a top view of a golf club head 100 in accordance with an embodiment of the present invention. Figure 2 shows a front view of the golf club head 100. The head 100 includes a plurality of dimples 105, as outlined in further detail below, which are configured to create a boundary layer of air, thereby reducing drag on the head 100 when swung.

[0070] Advantageously, the dimples 105 reduce drag on the head 100 without substantially changing the shape of the head 100. This allows for improved aerodynamics while complying with USGA and R&A Rules of Golf. Improved aerodynamics may require less effort to swing the club at a desired speed, which may in turn be associated with a reduced risk of injury. Alternatively, the improved aerodynamics may be used to increase swing speed. To compensate for the reduced drag, the head 100 can be adjusted as outlined below.

[0071] The golf club includes a driver, and the head 100 includes a striking face 110, a sole 115, a crown 120, a toe 125, a heel 130, and a hosel 135. The dimples 105 are spherical dimples that are substantially uniform in size and shape and extend substantially across the entire striking face 110 and to the tip portions of the sole 115, the crown 120, the toe 125, and the heel 130. These portions correspond to high-drag areas of the head 100 when swung.

[0072] The dimples 105 on the striking surface 110 are configured so as not to affect the golf ball struck by the club. In particular, the dimples 105 on the surface 110 are sized, shaped, and positioned so as not to impart any significant additional spin to the golf ball relative to a club that does not include such dimples 105. Such a configuration allows the dimples 105 on the surface 110 to have a minimal effect on the function of the striking surface 110 while improving aerodynamics. This is particularly useful for maintaining compliance with standards such as USGA standards.

[0073] Figure 3 shows a cross-sectional bottom view of a golf club head 100 of a golf club according to an embodiment of the present invention, and Figure 4 shows a cross-sectional side view of the golf club head 100. The golf club head 100 is adjustable, allowing a golfer to adjust the weight and balance of the golf club head.

[0074] The dimples 105 significantly reduce the drag of the golf club head 100, thereby significantly reducing the flex of the golf club shaft, which in turn changes the angle of attack of the golf club head 100, which in turn affects the trajectory of the golf ball.

[0075] Because the level of flex in a conventional golf club varies with swing speed, the change in flex caused by a reduction in drag is dependent on the speed of the swing and, therefore, the golfer. As such, adjustable weight 140 is provided in club head 110 to allow the golfer to compensate for such changes depending on their particular situation.

[0076] The golf club head 100 includes an elongated cylindrical chamber 145 that extends in a front-to-rear direction of the golf club head 100, behind and perpendicular to the face 110 of the club head 100, particularly in the central striking portion (commonly referred to as the "sweet spot").

[0077] Cylindrical chamber 145 includes a threaded rod 150 that extends through movable weight 140 and along the length of cylindrical chamber 145. Movable weight 140 includes internal threads that engage with the threads on threaded rod 150. Thus, as threaded rod 150 rotates, movable weight 140 moves back and forth within cylindrical chamber 140, thereby changing the balance of the golf club without changing the weight of the golf club.

[0078] The outer end of the threaded rod 150 includes a hexagonal head 155 that allows for rotation of the rod 150 using a tool. The head 155 may include a thin rubber seal to protect it, prevent water ingress, and / or conceal the head 155.

[0079] During a swing, the centrifugal force of the head causes the shaft to bend depending on the position of the weight 140. When the weight 140 is at the rear of the club, the centrifugal force pushes the rear of the club head 100 outward (downward), thereby increasing the angle of the face 110 upward. When the weight 140 is closer to the front of the head 100, this effect is minimized because the weight is closer to the bottom end of the shaft. The face angle affects the trajectory of the golf ball.

[0080] A non-adjustable weight 160 is located immediately behind the central striking portion of face 110 and is held against the rear of face 110 by a biasing member in the form of a spring 165 .

[0081] Weight 160 is slightly smaller than cylindrical chamber 145 and can move slightly back and forth within chamber 145. Weight 160 provides additional force to the back of face 110 and also generates a "ping" sound that helps the golfer identify when the ball hits face 110 in the sweet spot. In particular, the microsecond recoil creates more force on the back of face 110 and simultaneously creates a sound. The rebound effect of weight 160 provides additional force to the ball, potentially resulting in additional distance.

[0082] Weight 160 can move anywhere from 1 millimeter up to several millimeters (eg, up to 5 mm) in size within chamber 145 .

[0083] Weights 140, 160 are cylindrical in shape to match the shape of the interior of cylindrical chamber 145. Although weights 140, 160 are shown as substantially solid disks, in other embodiments, the front surface of weight 160 may be hollowed out, and weights 140, 160 may include indentations or openings.

[0084] In other embodiments, the chamber 145 and weights 140, 160 may be oval in cross section, adding weight that extends to either side of the central hitting area (sweet spot), which is particularly useful for golfers who do not always hit the sweet spot.

[0085] In some embodiments, the weight can include a central cylinder flanked by adjacent side cylinders. The central cylinder can be larger than the side cylinders and aligned with the central striking portion, while the side cylinders are located on either side of the striking portion. Using a central cylinder with adjacent side cylinders can include a weight that is lighter than an oval weight of a corresponding size.

[0086] In alternative embodiments, the golf club head may include multiple elongated chambers, each with a moveable weight and threaded rod similar to or identical to chamber 145. The chambers may be positioned in different directions. For example, one or more chambers may extend transversely to chamber 145. In particular, first and second chambers may be positioned on either side of chamber 145.

[0087] 5 shows a cutaway view of the bottom of a golf club head 500 according to an alternative embodiment of the present invention. The golf club head 100 is two-way adjustable, allowing the golfer to adjust the weight and balance of the golf club head in both the front-to-back and side-to-side directions.

[0088] In addition to cylindrical chamber 145 and movable weight 140, head 500 includes first and second lateral chambers 545 that extend from a central portion of head 500 to toe 125 and heel 130, respectively. Each of first and second lateral chambers 545 includes a threaded rod 550 and weight 540, which function much like weight 140 in chamber 145, except that weight 540 moves laterally instead.

[0089] As head 555 rotates, threaded rod 550 rotates, causing movable weights 540 to move laterally within cylindrical chamber 545, thereby changing the balance of the golf club without changing the weight of the golf club. Each of weights 540 can be adjusted independently, allowing the club to be balanced in multiple directions.

[0090] The chambers can be formed together as a single unit for placement inside a shell that defines the golf club head 500. Such a configuration can simplify the manufacturing process for the golf club head 500 by allowing such adjustments to be relatively easily incorporated into existing manufacturing systems.

[0091] While the above embodiment shows dimples on a large portion of the club face 110 and head 100, in other embodiments, channels are defined in the club head to direct air. The channels contain dimples, creating areas of low drag that aid in club direction.

[0092] FIG. 6 shows a top view of a golf club head 600 and FIG. 7 shows a front view of the golf club head 600 in accordance with an embodiment of the present invention.

[0093] The head 600 includes a plurality of channels 605 that extend behind and perpendicular to the face 610 of the club head 600 in a direction from the front to the rear of the golf club head 600. Each channel 605 includes dimples 105 that extend along the length of the channel 605, creating areas of low drag that aid in directing the club. The dimpled channels can provide more controlled movement through the air, helping to control the direction of the club head.

[0094] In particular, the channels 605 direct air from the front to the back of the club with low drag. If the club is swung at an angle, the channels help return the club head 600 to "straight," thereby helping the golfer improve their swing.

[0095] Channel 605 is approximately 0.5 mm to 5 mm deep and contains dimples along its length having a depth that is a fraction of the depth of channel 605 .

[0096] The striking face 610 includes a plurality of parallel grooves 615 machined or cast into the striking face 610. Dimples 105 may be located between adjacent grooves 605 to form rows of dimples parallel to the grooves to further aid in the aerodynamics of the club head 600.

[0097] Club head 600 may include internal weighting similar to or identical to the weighting of head 100 or head 500. The centrally located internal weighting and central channel with dimples (on the crown or sole) help control the direction of the club head (i.e., resulting in a more controlled swing). Additionally, the centrally located weighting directly behind the sweet spot, combined with reduced head drag, results in more power and greater ball distance.

[0098] In other embodiments, the channels containing the dimples may be defined in club heads having different shapes.

[0099] FIG. 8 shows a top view of a golf club head 800 according to an embodiment of the present invention.

[0100] Head 800 is similar to head 600, but channels 805 are all directed toward a point at or near the rear of club head 800. Such a configuration can be useful for directing air toward a point at the rear of the club, thereby reducing the overall drag associated with club head 800.

[0101] FIG. 9 shows a top view of a golf club head 900 in accordance with an embodiment of the present invention.

[0102] Head 900 is similar to head 800, but the single channel 905 tapers to direct air to a point at or near the rear of club head 900.

[0103] Figure 10 shows a top view of a golf club head 1000 according to an embodiment of the present invention, and Figure 11 shows a front view of the head 1000.

[0104] Head 1000 is similar to head 900, except that a single channel 1005 extends across most of the crown of club head 1000. Channel 1005 has a base that is curved in shape.

[0105] FIG. 12 shows a top view of a golf club head 1200 in accordance with an embodiment of the present invention.

[0106] Head 1200 is similar to head 900, except that channel 1205 is initially substantially uniform in width and then tapers toward the rear of club head 1200.

[0107] Figure 13 shows a top view of a golf club head 1300 according to an embodiment of the present invention. Figure 14 shows a front view of the head 1300.

[0108] Head 1300 is similar to head 600, but includes five parallel channels 1305 in the crown of the head. Head 1300 also has five parallel channels 1405 in the sole.

[0109] Figure 15 shows a top view of a golf club head 1500 according to an embodiment of the present invention. Figure 16 shows a bottom view of the head 1500.

[0110] Head 1500 includes tapered channels 1505, 1510 on the crown and sole of the club head and the internal weight mechanism of head 100. Head 1500 includes a removable cover 1515 (removed in FIG. 16 ) that provides access to the internal weight mechanism. Such a configuration may allow, for example, weight 140 to be removed and replaced with a smaller or larger weight.

[0111] When fully forward, as shown in Figure 16, the weight 140 is in front of the balance line of the club head 1500. When moved to the rear of the club head 1500, as shown in Figure 17, the weight 140 is fully behind (towards the rear) the balance line.

[0112] Thus, the balance of the club head 1500 can be significantly altered by moving the weight 140, thereby changing the angle of attack of the golf club when swung, which in turn changes the angle of the club face when the club strikes the golf ball, thereby affecting the shot.

[0113] Various methods of attaching the weight and cylinder to the interior of the club head can be used. In some embodiments, the weight assembly can be inserted into the head through its open side. Preferably, the internal weight mechanism is configured so as not to significantly change the expansion characteristics of the club head when striking a ball. In particular, golf club heads generally expand laterally when striking a golf ball, which in turn adds additional velocity to the golf ball when remolded.

[0114] FIG. 18 shows a cutaway perspective view of a golf club head 1800 according to an embodiment of the present invention.

[0115] The golf club head 1800 includes an elongated cylindrical chamber 1805 that extends in a front-to-rear direction of the golf club head 1800, behind and perpendicular to the face of the club head 1800, particularly to the "sweet spot."

[0116] Chamber 1805 houses a weight similar to or identical to weight 140, which can move back and forth within the chamber to adjust the balance of head 1800.

[0117] The chamber 1805 is supported by a plurality of legs 1810 that extend outwardly from the chamber 1805 , are perpendicular to the axis of the chamber 1805 , and engage the interior walls of the club head 1800 .

[0118] 19 shows a perspective view of a cutaway of a golf club head 1900, according to an embodiment of the present invention. Head 1900 is similar to head 1800, except that chamber 1805 is supported by framework 1910, which includes an inner portion encasing chamber 1805, an outer portion supporting against the inner wall of club head 1800, and arms extending therebetween.

[0119] The internal weight features described above may be used in conjunction with any of the dimple and / or channel arrangements described above.

[0120] As outlined above, the dimples 105 improve the aerodynamics of the golf club head. Figure 20 shows a golf club head 2000 that includes dimples 105 over its entire surface to illustrate how the dimples improve the aerodynamics of the golf club. Although head 2000 has dimples over its entire surface, the aerodynamic features may be applicable when the dimples are only present on a portion of the club head.

[0121] The dimples 105 create a boundary layer of turbulent air immediately adjacent to the dimples 105, as indicated by arrow 2005, over which smooth air may move, as indicated by arrow 2010. Such a configuration reduces the size of the wake area behind the golf club head 100 when swung, thereby reducing drag.

[0122] In other configurations and / or situations, the air may rotate across the dimple, causing the air to flow in a smooth, undulating pattern. In such cases, the velocity may exit the dimple at a higher velocity (up to twice as fast) than it entered the dimple.

[0123] In addition to providing a golf club head that includes dimples, embodiments of the present invention provide a cover that can be used to add dimples to a golf club head after manufacture.

[0124] Figure 21 shows a partially exploded side view of a golf club head 2100 including a head portion 2105 and a dimpled cover 2110 (shown separated). Figure 22 shows a cross-sectional view of the dimpled cover 2110, and Figure 23 shows a front view of the golf club head 2100 with the cover 2110 attached.

[0125] Head portion 2105 may include a conventional golf club head, and dimpled cover 2110 may be selectively attached to the front of the golf club head to improve its aerodynamics.

[0126] The dimpled cover 2110 is thin and conforms to the front of the head 2105 and may be attached by any suitable means, including clip-on means or by the use of adhesive.

[0127] As can be seen from FIG. 23, the dimples extend not only to the striking face but also to the crown, sole heel, and toe of the club head 2100 .

[0128] 24 shows a partially exploded side view of a golf club head 2400 including a head portion 2405 and a dimple cover 2410 (shown separated). The golf club head 2400 is similar to the club head 2100, except that the cover 2410 extends further into the head. This configuration helps provide more aerodynamics to the head 2400.

[0129] The golf club head described above may include first and second dimples 105 that differ from one another in size and / or shape. As an illustrative example, the dimples 105 on the striking face 110 may be smaller in depth or diameter than the dimples 105 not on face 110. The dimples on face 110 may be approximately 0.04 mm deep, and the dimples not on face 110 may be approximately 0.1 mm deep.

[0130] The dimples 105 may be arranged in rows on the head, the rows being parallel to the sole (or baseline) of the head. Secondary dimples may be arranged in rows perpendicular to the sole (or baseline), thus forming a matrix of dimples.

[0131] In an alternative embodiment, the dimples may be integrated into a honeycomb-like arrangement, where the dimples are tightly packed with little or no gaps on the surface of the club head, and in some cases, the dimples (or their edges) may touch each other.

[0132] The dimples 105 are spherical dimples that are configured so that the edge between the surface (of the club head) on which the dimples 105 are located and the dimples 105 themselves is approximately 45 degrees or less.

[0133] Various other types of dimple shapes can be used. In some embodiments, the dimples can be configured to be directional rather than axisymmetric to promote air flow in a direction corresponding to the swing of the golf club (i.e., from front to back as the golf club is swung).

[0134] The dimples may be sinusoidal in cross section in a plane perpendicular to the face (of the club head). In such a configuration, the edges between the face and the dimples are eliminated. As a result, the dimples do not include gripping edges, which may reduce interaction with the golf ball or alter the characteristics of the turbulent boundary layer if present on the striking surface.

[0135] In yet another embodiment, the dimples may be hexagonal dimples.

[0136] In some embodiments, hexagonal dimples can be combined with spherical dimples or dimples of another shape. For example, spherical dimples (or dimples with circular cross-sections) can be located on the striking face of a golf club head, while hexagonal dimples can be located on one or more other surfaces of the head.

[0137] The hexagonal dimples may be arranged so that adjacent dimples are adjacent to one another in a honeycomb arrangement. However, the hexagonal dimples may also be spaced apart in a manner similar to the spherical dimples 105 outlined above. Similarly, the spherical dimples may be arranged in groups of dimples, with smaller and larger dimples grouped in triangular sections. In short, any suitable shape and arrangement of dimples may be used.

[0138] At least 10% of the surface of the golf club head may be covered with dimples. In some embodiments, at least 50% of the surface of the head may be covered with dimples. Substantially the entire surface of the body may be covered with dimples.

[0139] Although a driver is explicitly shown, the dimples may be provided on any suitable type of golf club.

[0140] The golf club heads described above can be formed of metal. Surface features (i.e., dimples or beads) can be cast into the head. Alternatively, the surface features can be machined, pressed, or engraved into the head.

[0141] In one embodiment, a golf club head may be formed from multiple pressed pieces of metal. In the case of a driver, each piece may be pressed with dimples to shape and micro-welded to form the club head. Weights or other components may be added to the inside of the club head during this process. Finally, small breather holes may be provided to allow hot air to escape during manufacturing. The breather holes may be sealed after manufacturing.

[0142] In another embodiment, the golf club head may be 3D printed of a metal, a metal alloy, a combination of metal and another material (e.g., polycarbonate), carbon fiber, nylon, or any other suitable material. In such cases, the golf club head may be custom printed for a single user or mass-produced using such 3D printing.

[0143] Alternatively, the head may be formed entirely or partially from other materials, for example, the head may be formed from resin, polycarbonate, composite material, or any other suitable material.

[0144] The head can be formed as a single piece. Alternatively, the head can be formed from two or more components. For example, the head can be formed of metal with a thin polycarbonate sleeve covering a portion of it, with at least some of the surface features (e.g., dimples or beads) disposed in the polycarbonate sleeve.

[0145] The exact number, size, shape, and placement of the dimples can vary depending on the size and shape of the golf club head and / or one or more desired characteristics of the golf club. Similarly, the number, size, shape, and placement of the dimples or beads can be balanced according to the cosmetic appearance of the golf club head. Regardless of the number, size, shape, or placement, the dimples can be smooth to the touch.

[0146] The golf club may be USGA compliant. In such cases, the dimples may be positioned so that they do not engage the ball in any significant way. Unlike grooves, punch marks, etc., which are designed to impart spin to the ball, the dimples may be positioned so as not to grip the ball and therefore not alter its motion. As outlined above, this may be achieved by having dimples that form edges with angles less than 45 degrees, or by not having any significant edges at all. Similarly, dimples may be positioned on a portion of the face of the golf club that does not generally contact the golf ball in use. As an illustrative example, the sweet spot (or the area surrounding the sweet spot) may be devoid of dimples.

[0147] Although a golf club is shown, the teachings of the present invention may be applied to many sports equipment adapted to be swung by a user. Such sports equipment may include a handle and a striking surface configured to strike a ball or other equipment, and may include improved aerodynamics and / or balance.

[0148] As illustrative examples, sporting equipment may include a club (e.g., a golf club), a racket (e.g., a tennis, squash, or badminton racket), a bat (e.g., a baseball bat), or a stick (e.g., a hockey stick). Embodiments of the present invention also include a helmet having dimples on its exterior surface to improve the aerodynamics of the helmet, thereby reducing drag and simultaneously increasing ventilation of the helmet.

[0149] Figure 25 shows a front view of motorcycle helmet 2500 in accordance with an embodiment of the present invention. Figure 26 shows a side view of motorcycle helmet 2500, and Figure 27 shows a rear view of motorcycle helmet 2500. Motorcycle helmet 2500 is shaped similarly to a conventional motorcycle helmet, but includes a ventilation mechanism for ventilating the helmet.

[0150] In particular, helmet 2500 includes a channel 2505 that extends from an opening 2510 at the front of helmet 2500 to an outlet 2515 at the rear of helmet 2500. Channel 2505 includes a plurality of dimples 2520 on the exterior surface of opening 2510 and extending through channel 2505. Dimples 2520 increase airflow through channel 2505, thereby increasing ventilation through helmet 2500.

[0151] Figure 28 shows a top view of helmet 2500, and Figure 29 shows a side cross-sectional view of the helmet through line AA in Figure 28. As best seen in Figures 28 and 29, air flow passage 2525 is provided between the interior of helmet 2500 and channel 2505. Because outlet 2515 is larger than the central portion of channel 2505, a Venturi effect is created in channel 2505, thereby creating a low pressure in the channel at air flow passage 2525. This low pressure causes air to flow through air flow passage 2525, thereby ventilating the helmet.

[0152] 29, a raised cover 2530 is provided over each air channel 2525 in an inverted cowl-like arrangement to prevent water leakage into the helmet when it is raining. In particular, as air flows through the channels 2505, any water containing the air flows through the channels 2505. Each air channel 2525 is protected by a cover 2530 that protrudes from the opening of the air channel 2525, and any water in the channel travels from the channel 2505 along the top of each cover 2530.

[0153] The covers 2530 are arranged in rows corresponding to the traction of the air flow passages 2525. Groove-like valleys 2535 are defined between adjacent rows, which also serve to transport any water flowing from the channels 2505 back into the channels 2505.

[0154] FIG. 30 shows a cross-sectional front view of the helmet 2500, illustrating two different types of air flow paths 2525 through the helmet 2500.

[0155] Air flow channels 2525 include air grooves 2525a defined in the inner surface (foam) of helmet 2500. Grooves 2525a extend vertically along the height of helmet 2500, thus allowing air to flow from any point inside helmet 2500. The grooves allow air entering the bottom of helmet 2500 to flow along the entire interior of helmet 2500 adjacent the rider's head, thereby cooling helmet 2500 and therefore the rider's head.

[0156] Air flow passages 2525 also include horse-shaped channels 2525b defined in the interior surface of helmet 2500. Channels 2525b extend from an opening at the bottom of helmet 2500 to the outlet of channel 2505. Channels 2525b generally extend from different portions of helmet 2500 to channel 2505, thereby ventilating helmet 2500. Air flow passages 2525 may include dimples therein to improve airflow through passages 2525.

[0157] Although grooves 2525a and channels 2525b are shown on each side of the helmet, in a typical scenario, only grooves 2525a or channels 2525b will be used on the sides of the helmet, and the presence of both on a single helmet is simply to show different options in a simple manner.

[0158] Figure 31 shows a cross-sectional side view of helmet 2500 showing area B of Figure 29. Figure 32 shows a cross-sectional side view of helmet 2500 showing area C of Figure 31.

[0159] The covers 2530 have bases 2530b attached to the lower ends of the channels 2505 and overhanging upper cover portions 2530a located directly above the air flow passages 2525. The covers 2530 are arranged end to end in respective rows such that the upper cover portion 2530 of one cover 2530 overlaps / overhangs the base 2530b of an adjacent cover 2530.

[0160] The edge of the base 2530a includes a lip 2530c that prevents any water that drips from one cover from entering the air flow passage 2525.

[0161] As outlined above, dimples 2520 are provided on the exterior surface of opening 2510 and through channel 2505. In particular, dimples are provided in cover 2530 to increase air flow through channel 2505.

[0162] FIG. 33 shows a side cross-sectional view of helmet 2500 showing use, according to an embodiment of the present invention.

[0163] As air moves over the smooth surfaces of the sides of the helmet and the air at the top moves away from the surface, a lower air pressure is created behind the helmet, as shown by arrow 3305.

[0164] The front vents of the channels 2505 combined with the dimples 2520 create turbulence as indicated by arrows 3310, thereby reducing resistance to air flowing inside the helmet.

[0165] The channel 2505 tapers to a larger sized opening at the rear of the helmet, creating a venturi effect and lower pressure at circle 3315 .

[0166] The Venturi effect draws air, as indicated by arrows 3320, from the inside of the helmet, through air flow passages 2525 (which act as ducts), into channel 2505, and then out through the rear of the helmet.

[0167] Although not shown, the helmet 2500 will generally include a visor, and air channels 2525 in the front of the helmet are configured to ventilate the visor, thereby preventing fogging of the visor.

[0168] While the above description shows several independent air channels 2525, one skilled in the art will readily understand that multiple air channels may be combined. For example, the air channels may be combined in a branched manner and / or form a network of air channels. As an illustrative example, a single (or a small number of) openings may be coupled to branching air channels in multiple portions of the helmet.

[0169] In some embodiments, the channel 2505 may include a shutter to allow the wearer to adjust the level of flow through the channel 2505 and therefore the level of ventilation of the helmet 2500.

[0170] Figure 34 shows a side view of a helmet 3400 with a shutter 3405 in a closed position, and Figure 35 shows a side view of a helmet 3400 with a shutter 3405 in an open position, according to an embodiment of the present invention.

[0171] The shutter 3405 slides up and down to open and close the opening 2510, thereby opening and closing the channel, allowing the helmet wearer to adjust the level of airflow through the channel 2505 and thereby adjust the level of ventilation in the helmet.

[0172] Although not shown, the helmets 2500, 3400 may include dimples on their exterior surfaces, in which case the dimples are arranged in rows from the front to the rear of the helmet, thereby directing airflow from the front to the rear of the helmet.

[0173] The helmets 2500, 3400 may further include molded channels that direct airflow across the helmet. The molded channels may taper toward the rear of the helmet, and multiple dimples may extend along the length of the channels. The inventors believe that the use of dimples in the channels improves aerodynamics more than a single channel or dimple alone.

[0174] As outlined above, the helmet 2500, 3400 may include a visor. The visor may have dimples on its surface to optimize airflow without obstructing visibility. The visor may be partially or fully dimpled. In a partially dimpled configuration, the dimples may leave a distinct visual strip (i.e., removed from the dimples). In a fully dimpled configuration, the dimples may be sized so as not to significantly affect visibility through the visor.

[0175] The dimples may be uniform in shape and / or size, or may include multiple shapes and / or sizes. Any suitable shape or combination of shapes that falls within the regulations for that helmet.

[0176] Although the above embodiment shows a motorcycle helmet, those skilled in the art will readily appreciate that the present invention can be used with any type of helmet, including sports helmets (e.g., bicycle helmets), and helmets designed for use on land and in water.

[0177] Advantageously, the helmet may reduce drag, which in turn may improve performance and / or reduce stress on the user's head.

[0178] As outlined above, other types of sporting equipment can incorporate the above teachings.

[0179] Figure 36 shows a tennis racket 3600 in accordance with an embodiment of the present invention. Figure 37 shows an interior view of area D in Figure 36, Figure 38 shows a front view of area D, and Figure 39 shows an exterior view of area D.

[0180] The tennis racket 3600 includes a body in the form of a frame 3600a, a handle 3600b, and a number of strings (not shown for clarity) disposed in an opening defined by the frame 3600a.

[0181] The frame 3600a includes a plurality of dimples 3605 arranged in channels 3610, which create a boundary layer of air directly adjacent to the frame 3600a, thereby reducing the drag of the frame 3600a (and therefore the racket 3600) when swung by a user.

[0182] The dimples 3605 may be similar or identical to the dimples described above in the context of golf clubs and helmets.

[0183] The dimples 3605 extend around the frame 3600a in the channel 3610 and are therefore located on both the inside, side, and outside of the racquet 3600. This maintains symmetry and allows the racquet 3600 to function in both directions.

[0184] Much like the golf club above, the Racket 3600 reduces wind resistance, which can reduce the risk of injury and increase swing speed.

[0185] In an alternative embodiment, the racket may include weights similar to those described above to adjust the balance of the tennis racket.

[0186] Figure 40 shows a front view of a tennis racket 4000 according to an embodiment of the present invention. Figure 41 shows region E of Figure 40, Figure 42 shows an end view of the handle 4000b of the racket 4000, and Figure 43 shows a cross-sectional view of the handle 4000b through FF of Figure 41.

[0187] Tennis racket 3600 includes a body in the form of a frame 4000a similar to body 3600a and including dimples. Strings (not shown for clarity) are provided in openings defined by frame 4000a.

[0188] Frame 4000a includes a plurality of dimples arranged in channels that, as outlined above with respect to racket 3600, create a boundary layer of air directly adjacent to frame 4000a, thereby reducing the drag of frame 4000a (and therefore racket 4000) when swung by a user.

[0189] Handle 4000b includes a weight 4005 that is movable along the length of handle 4000b to alter the balance of the handle and racket 4000. In particular, handle includes a cylindrical chamber 4010 along which weight 4005 can move. Weight 4005 fits snugly within chamber 4010 so that it does not move or rattle during use.

[0190] A knob 4015 is provided on the weight 4005, which allows the position of the weight 4005 to be adjusted within the chamber 4010. The knob 4015 extends through an elongated channel 4020, which allows access to the knob 4015 from outside the handle 4000b, while also providing a visual indicator of the position of the weight 4005 relative to the handle 4000b.

[0191] Moving the weight 4005 up towards the strings provides a more powerful serve. Moving the weight 4005 towards the bottom of the handle provides a more balanced racket 4000.

[0192] The handle 4000b further includes a removable end cap 4025 that can provide access to the chamber 4010, for example, to allow the weight 4005 to be replaced or removed.

[0193] Although the chamber is shown as cylindrical, those skilled in the art will readily appreciate that it can take any suitable shape, but is preferably uniform in cross section along its length.

[0194] The handle may be constructed in two parts, with the cylindrical chamber defined in one part, which is particularly useful when the frame is defined continuously around the opening from one side of the handle and back to the other side of the handle, as in the case of a bent-tube tennis racket.

[0195] In an alternative embodiment, the lower end of the handle rotates, thereby allowing the weight to be moved up and down within the handle, for example using a threaded shaft and cylindrical chamber much like a golf club but of a size and shape suitable for the handle.

[0196] The handle can be extended in length compared to a typical handle, thereby allowing the weight to travel a greater distance relative to the user's hand, which in turn allows the weight to be placed higher and therefore apply more force to the tennis ball.

[0197] 44 shows a front view of a tennis racket 4400 with a weight assembly, according to an embodiment of the present invention. Certain portions of the weight assembly, which are normally hidden by the handle, are shown to clearly illustrate the weight assembly.

[0198] Tennis racket 4400 is similar to racket 4000 and includes a frame 4400a that includes dimples, and strings (not shown for clarity) are provided in openings defined by frame 4400a.

[0199] The racket 4400 includes a handle 4400b and a weight 4405 that is movable along the length of the racket 4400 along the axis of the handle 4400b to change the balance of the handle and the racket 4400. In particular, a cylindrical chamber 4410 extends outward from the end of the handle 4400b toward an opening along which the weight 4405 can be moved. The weight 4405 fits snugly within the chamber 4410 so that it does not move or rattle during use.

[0200] The shaft 4415 extends along the length of the handle 4400b and engages the weight, allowing the position of the weight 4405 to be adjusted within the chamber 4410. The shaft may be threaded, or at least partially threaded, whereby adjustment of the weight 4405 is performed by rotating the shaft (similar to adjusting the weight in a golf club head described above). Alternatively, the shaft 4415 may move longitudinally within the handle, thereby moving the weight 4405 longitudinally in the chamber 4410.

[0201] Moving the weight 4405 up towards the strings provides a more powerful serve. Moving the weight 4405 towards the bottom of the handle provides a more balanced racket 4400.

[0202] As noted above, altering the aerodynamics of sporting equipment relieves stress and strain from the user's body, including the pelvis and hips, back, elbows, shoulders, neck, wrists, and soft tissue areas of the body.

[0203] The surface features reduce drag on the sports equipment without substantially changing the shape of the sports equipment. This can improve aerodynamics while complying with USGA and R&A rules for golf clubs. Improved aerodynamics can reduce the effort required to swing the sports equipment at a desired speed, which can be associated with a reduced risk of injury. Alternatively, improved aerodynamics can be used to increase swing speed.

[0204] The above embodiments are exemplary only, and one skilled in the art will readily appreciate that any suitable pattern or configuration of dimples or impressions may be used on any portion of a golf club, sports equipment, or helmet, such as using multiple patterns or configurations on various portions of a golf club, sports equipment, or helmet.

[0205] The dimples or impressions may have any suitable depth, including a depth proportional to the diameter of the dimple or impression. Furthermore, the depth of the dimple or impression, or the depth relative to the diameter, may be selected so as to provide maximum (or near maximum) efficiency in use.

[0206] Such maximum efficiency may include reference to a direction that takes into account the speed at which air moves over a portion of the golf club, sports equipment, or helmet, and the aerodynamics and efficiency of the golf club, sports equipment, or helmet. As an illustrative example, if the golf club, sports equipment, or helmet is designed to move in a particular direction, the dimples or impressions may be configured to enhance the aerodynamics and efficiency of the golf club, sports equipment, or helmet as it moves in such direction.

[0207] In this specification and claims (if any), the word "comprise" and its derivatives, including "comprises" and "comprise", include each of the listed integers but do not exclude the inclusion of one or more additional integers.

[0208] References throughout this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification do not necessarily all refer to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

[0209] In accordance with the statute, the invention has been described in language more or less specific by structural or methodological features. It will be understood that the invention is not limited to the particular features shown or described, since the means described herein include preferred forms of embodying the invention. The invention is therefore claimed in any of its forms or modifications within the proper scope of the appended claims (if any) as appropriately interpreted by those skilled in the art.

Claims

1. A golf club including a head, a plurality of dimples configured to reduce drag on the head when swung by a user; and an internal chamber defined in the head, the internal chamber including one or more internal weights movable within the internal chamber to adjust the balance of the head; The chamber is disposed in the center of the head.

2. The golf club of claim 1 , wherein the dimples include spherical dimples or hexagonal dimples.

3. 10. The golf club of claim 1, wherein the dimples have a depth of between about 0.01 mm and 1.5 mm and a diameter of between about 0.5 mm and 3 mm.

4. The golf club of claim 1 , wherein one or more of the dimples are located on the striking face of the head.

5. The golf club of claim 4 , wherein the striking face includes a plurality of elongated grooves, and at least some of the dimples are located between adjacent grooves.

6. 2. The golf club of claim 1, wherein the dimples include first dimples and second dimples, the first dimples being substantially uniform in size and shape, the second dimples being substantially uniform in size and shape, and the first dimples being different from the second dimples in at least one of size and shape.

7. The golf club of claim 1 , wherein at least some of the dimples are arranged in rows, the rows being parallel or perpendicular to an edge of the golf club.

8. 3. The golf club of claim 2, wherein at least 50% of the surface of the head is covered with dimples.

9. The golf club of claim 1 , wherein the weight is adjustable in position from outside the head of the golf club.

10. The golf club of claim 1 , wherein the chamber is elongated in a direction substantially perpendicular to the striking face of the golf club, and the internal chamber is substantially uniform in cross section.

11. The golf club of claim 1 including one or more weights biased against the front face of the head with a biasing member such as a spring.

12. 12. The golf club of claim 11, wherein the one or more weights move partially within the internal chamber when the golf club strikes a ball to produce a pinging sound when the club strikes a ball.

13. 10. The golf club of claim 1, including a threaded rod configured to engage a weight within the internal chamber, such that the weight can move along the length of the internal chamber through rotation of the threaded rod.

14. The golf club of claim 1 , wherein the interior chamber comprises a cylindrical chamber and the one or more weights are disk-shaped.

15. The golf club of claim 1 , wherein the interior chamber is supported by one or more arms and an interior surface of the head.

16. The golf club of claim 1 including a channel defined in a surface of the head, wherein at least a subset of the dimples are defined in the channel.

17. The golf club of claim 16 , wherein the channel is defined on a crown of the head.

18. The golf club of claim 16 , wherein the channel is tapered.

19. The golf club of claim 16 , wherein the channel comprises a plurality of channels.

20. A golf club including a head, a plurality of dimples configured to reduce drag on the head when swung by a user; and an internal chamber defined in the head, the internal chamber including one or more internal weights movable within the internal chamber to adjust the balance of the head; The interior chamber is supported by one or more arms and an interior surface of the head.

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