Abstract: A sole of a head is inclined upwardly toward a side of a hosel section. A proximal section of the hosel section, which is continuous to a top, is set to be low. Accordingly, the weight of the head on the side of the hosel section is reduced, while the weight is distributed to circumferential portions of the head. Thus, the moment of inertia is set to be increased, and the sweet area is substantially enlarged.

Abstract: In one aspect, a correlated set of individually numbered golf club iron heads progresses from a high numbered head to a low numbered head. Individual heads have a front striking face, a rear face, a sole, a toe, a heel and a hosel. The front striking faces of heads within the set individually have a total planar area defining a progressively decreasing loft angle in going from the high numbered head to the low numbered head. For at least two chosen pairs of heads within the set, the striking face total planar area of individual heads within each chosen pair increases in size in going from the higher numbered head to the lower numbered head in the pair. In another aspect, a correlated set of individually numbered golf club iron heads comprises at least a 3-iron head, a 4-iron head and a 5-iron head. The hosel is provided relative to the sole to provide a different and increasing lie angle in sequentially progressing from the 3-iron head to the 5-iron head.

Abstract: A set of golf clubs, each of the clubs in the set having substantially the same loft angle and each of the clubs in the set has a shaft length that is different from the other clubs in the set. The loft angle is preferably between about 40 and 50 degrees.

Abstract: The present invention is directed at varying the thickness of a striking plate of a golf club head according to the loft angle of the golf club head. The thickness of the striking plate is greater for lower loft angles, such as seven, eight and nine degrees loft angle drivers, as compared to ten, eleven and twelve degrees loft angle drivers. The striking plate may have a variable face thickness with the thickest region near the center.

Abstract: A golf club or set of golf clubs include a sole having four surfaces: a bottom crescent surface, a positive bounce surface, a heel surface and a toe surface. The bottom crescent surface has a generally straight back boundary approximate the trailing edge and a curved front boundary. Moreover, the bottom crescent surface is substantially flat with the ground when the club addressed by the player.

Abstract: The invention includes a golf club iron head, correlated sets of individually numbered golf club irons, methods of matching a golf club to a golfer, and methods of matching a set of golf clubs to a golfer. In one implementation, a golf club iron head includes a front striking face, a sole, a toe, and a heel. The front striking face has a series of grooves of a common cross sectional shape from the top to the bottom. Individual grooves have a base and opposing sidewalls which diverge from the base and extend outwardly in the direction of the front striking face. The sidewalls include opposing protrusions extending into the groove proximate the front striking face. In one implementation, the front striking face of a golf club iron head defines a symmetrical groove cross section. The groove base comprises a protrusion extending in the direction of the front striking face. The base protrusion has an apex received inwardly of the front striking face.

Abstract: A golf club head comprises a ball striking face having a loft angle of from 6 to 30 degrees, and has a depth of the gravity center of not less than 18 mm, wherein the ball striking face is provided with a high frictional region of which maximum static friction coefficient at a high load of 400 kgf is not less than 0.35 whereby back spin of a hit ball is decreased and the flying distance of the ball can be increased. The high-load friction coefficient can be obtained by means of surface treatment, for example, etching, blasting, polishing, spraying a metal compound, vapor deposition of a metal compound and the like.

Abstract: A golf club or set of golf clubs include a sole having four surfaces: a bottom crescent surface, a positive bounce surface, a heel surface and a toe surface. The bottom crescent surface has a generally straight back boundary approximate the trailing edge and a curved front boundary. Moreover, the bottom crescent surface is substantially flat with the ground when the club addressed by the player.

Abstract: The present invention is directed varying the thickness of a striking plate of a golf club head according to the loft angle of the golf club head. The thickness of the striking plate is greater for lower loft angles, such as seven, eight and nine degrees loft angle drivers, as compared to ten, eleven and twelve degrees loft angle drivers. The striking plate may have a variable face thickness with the thickest region near the center.

Abstract: A golf club having a club head having with a coefficient of restitution greater than 0.845 and a durability to withstand 2000 impacts with a golf ball at 110 mile per hour is disclosed herein. The club head may be composed of three pieces, a face, a sole and a crown. Each of the pieces may be composed of a titanium material. The club head may be composed of a titanium material, have a volume in the range of 175 cubic centimeters to 400 cubic centimeters, a weight in the range of 165 grams to 300 grams, and a striking plate surface area in the range of 4.00 square inches to 7.50 square inches.

Abstract: The present invention is directed at varying the thickness of a striking plate of a golf club head according to the loft angle of the golf club head. The thickness of the striking plate is greater for lower loft angles, such as seven, eight and nine degrees loft angle drivers, as compared to ten, eleven and twelve degrees loft angle drivers. The striking plate may have a variable face thickness with the thickest region near the center.

Abstract: In an iron club set, the lie angle of each iron club in an iron club set is selected to be 61 degrees or larger. The lie angles of the iron clubs are set at a fixed value for every type of the iron clubs including a short iron to a long iron or progressively increase in angle value from the short iron to the long iron. Further, a ratio (L/H) of the minimum height (L) of the face at the heel to the maximum height (H) of the face of the club head, progressively increase in value in going to the long irons.

Abstract: A golf club has grooves across its face that are angled from an upper face section positioned relatively toward a toe of the club to a lower face section positioned relatively toward the heel with respect to the sole of the golf club instead of being parallel with a sole of the club. The angled grooves cause a sideways spin to be imparted to a struck golf ball. In one application, the angled grooves impart a spin that corrects for what would otherwise be a slice. The grooves can be at different angles, depending upon the golf club and the application. In an embodiment, the low irons and woods will have the grooves at a relatively higher angle than the mid irons, which will have the grooves at a higher angle than the approach irons and wedges. Clubs having such angled grooves can be structured according to USGA or other rules, but need not be.

Abstract: A golf club equivalent in driving distance to a standard 2-iron, 3-iron, 4-iron, 5-iron or 6-iron, where each club varies from the equivalent standard iron club in that the shaft is shorter, the loft angle is decreased, the lie angle is increased, and the club head weight is increased, where the swing weight remains approximately the same and where the club head is a metal club head of the type used for drivers and fairway woods.

Abstract: A self-aligning, low or no self-torque club that is both statically- and dynamically-balanced is provided which is less prone to deleterious effects during its approach to and while striking the ball Static balance is achieved by ensuing the shaft axis intersects the line between the geometric center of the club face and the center of gravity of the club head. The club is self-aligning because the center of gravity naturally follows the shaft and since the shaft and center of gravity are in-line with the face center, the possibility of striking the ball with the club face square increases. By providing a symmetrical and, preferably elliptical face, forces due to air resistance act equally on both sides of the face with respect to the shaft further aligning the club face with the swing path. To further alignment, the club head may also be provided with a series of convergent channels in the direction of air flow over the club.

Abstract: A golf club, particularly adapted for use with an oversized iron-type head including an iron-type head and a shaft particularly adapted to overcome the droop effect and increase stability upon off-center impact. The iron-type head defines a sole portion, an impact face, a back portion and a hosel extension defining an opening. The shaft has a butt portion and a tip portion. The tip portion has a substantially straight profile and defines an outer diameter d greater than or equal to 0.38 inches and less than or equal to 0.40 inches (i.e., 0.38 inches≦d≦0.40 inches). The shaft has a weight W less than or equal to 85 grams (W≦85 grams). At least a part of the tip portion is positioned within the opening of the head. Desirably, the tip portion has a length of greater than or equal to 2 inches.

Abstract: The golf club has a length over 0.99 m, a loft angle of at least 35°, a head mass of about 0.260 kg or less, and a lie angle of less than 60°. The golf club allows long and high slots.

Abstract: In one aspect, a correlated set of individually numbered golf club iron heads progresses from a high numbered head to a low numbered head. Individual heads have a front striking face, a rear face, a sole, a toe, a heel and a hosel. The front striking faces of heads within the set individually have a total planar area defining a progressively decreasing loft angle in going from the high numbered head to the low numbered head. For at least two chosen pairs of heads within the set, the striking face total planar area of individual heads within each chosen pair increases in size in going from the higher numbered head to the lower numbered head in the pair. In another aspect, a correlated set of individually numbered golf club iron heads comprises at least a 3-iron head, a 4-iron head and a 5-iron head. The hosel is provided relative to the sole to provide a different and increasing lie angle in sequentially progressing from the 3-iron head to the 5-iron head.

Abstract: A golf club set in which the weight balance of club shafts is optimized for each individual club. The weight balance at the grip-end of the shaft of each of the individual golf clubs increases as the corresponding loft angles of each of the individual golf clubs increase.

Abstract: A golf club set in which the attenuation rate of torque oscillation of club shafts is optimized for every individual club. The attenuation rate of torque oscillation of club shafts is controlled so as to be larger as the corresponding loft angles of the clubs increase.

Abstract: A golf club set in which the attenuation rate of torque oscillation of club shafts is optimized for every individual club. The attenuation rate of torque oscillation of club shafts is controlled so as to be larger as the corresponding loft angles of the clubs increase.

Abstract: A golf club set in which the weight balance of club shafts is optimized for each individual club. The weight balance at the grip-end of the shaft of each of the individual golf clubs increases as the corresponding loft angles of each of the individual golf clubs increase.

Abstract: In one aspect, a correlated set of individually numbered golf club iron heads progresses from a high numbered head to a low numbered head. Individual heads have a front striking face, a rear face, a sole, a toe, a heel and a hosel. The front striking faces of heads within the set individually have a total planar area defining a progressively decreasing loft angle in going from the high numbered head to the low numbered head. For at least two chosen pairs of heads within the set, the striking face total planar area of individual heads within each chosen pair increases in size in going from the higher numbered head to the lower numbered head in the pair. In another aspect, a correlated set of individually numbered golf club iron heads comprises at least a 3-iron head, a 4-iron head and a 5-iron head. The hosel is provided relative to the sole to provide a different and increasing lie angle in sequentially progressing from the 3-iron head to the 5-iron head.

Abstract: A golf club has grooves across its face that are angled from an upper face section positioned relatively toward a toe of the club to a lower face section positioned relatively toward the heel with respect to the sole of the golf club instead of being parallel with a sole of the club. The angled grooves cause a sideways spin to be imparted to a struck golf ball. In one application, the angled grooves impart a spin that corrects for what would otherwise be a slice. The grooves can be at different angles, depending upon the golf club and the application. In an embodiment, the low irons and woods will have the grooves at a relatively higher angle than the mid irons, which will have the grooves at a higher angle than the approach irons and wedges. Clubs having such angled grooves can be structured according to USGA or other rules, but need not be.

Abstract: An iron golf club set comprises a plurality of iron golf clubs having respective club numbers different from each other. Sole widths of the iron golf clubs become gradually larger from No. 7 iron club toward a lower lofted iron club having the smaller loft angle than that of the No. 7 iron club and a higher lofted iron club having the larger loft angle than that of the No. 7 iron club. The sole widths of No. 5 iron club and iron golf clubs having the smaller loft angle than that of the No. 5 iron club are larger than the sole width of a sand wedge.

Abstract: A golf club iron has a metallic club head including a solid metallic club head body with a bottom surface including a sole that contacts a flat surface when the bottom surface of the club head is placed onto a flat surface, a top surface, a hosel extending from the club head body, and a front face on the club head body. The heel and toe of the club are angled upwardly from a trailing edge central sole region, so that a central sole region has a length of from about 1/4 inch to about 3/4 inch to reduce the potential contact area of the club head with the ground. There is a recess in the rear face of the club head body, with a rim around the recess having a thickness of from about 5/16 inch to about 1 inch measured in the central portion of the rear face of the club head body, to lower the center of gravity of the club head.

Abstract: The present invention relates to a set of iron clubs. It is an object of the present invention to provide a set of iron clubs in which the directivity of a ball hit with an iron club belonging to a group of long iron clubs used for hitting the ball strongly so as to get distance can be stabilized and the time to close the face of the head can be made to coincide with each other so that it is easy for a player to hit a ball with the iron club. A set of iron clubs composed of a plurality of iron clubs, the club numbers of which are different from each other, are characterized in that: distances of the centers of gravity of the head bodies of groups of long iron clubs and short iron clubs are respectively set in a predetermined size range; and the distances of the centers of gravity of the group of long iron clubs are set smaller than the distances of the centers of gravity of the group of short iron clubs.

Abstract: A golf wood club having a loft angle of 16 degrees or less, a face height of 40 mm or more, a head volume V of 270 to 450 ml, a head weight G of 160 to 190 g, and a shaft length S of 120 cm or more, the shaft length S being in the range expressed by the following inequality:298-1.023G.ltoreq.S<315.8-1.023GA driver club for golfers having small power of swing as an embodiment of the above golf wood club is prepared in accordance with a specific philosophy of design and does not show decrease in the reproducibility of good shot, such as a decrease caused by push out, although the driver club has a length of 120 cm (about 47 inches) or more, preferably 125 cm (49 inches) or more, more preferably 129 cm (51 inches) or more. A fairway wood club as another embodiment of the above golf wood club is prepared in accordance with the same specific philosophy of design and has a length of 120 cm (about 47 inches) or more, preferably 125 cm or more.

Abstract: (1) A golf wood club having a loft angle of 16 degrees or less, a head volume V of 270 to 450 ml, a head weight G of 160 to 195 g, and a shaft length S of 120 cm or more, the shaft length S being in the range expressed by the following inequality:315.8-1.023G.ltoreq.S.ltoreq.327.8-1.023G;and (2) a golf wood club having a loft angle in the range of 15 to 20 degrees, a face height of 30 to 40 mm, a head volume V of 180 to 300 ml, a head weight G of 170 to 200 g, and a shaft length S of 120 cm or more, the shaft length S being in the range expressed by the following inequality:315.8-1.023G.ltoreq.S.ltoreq.327.8-1.023G.The golf wood clubs do not show decrease in the reproducibility of good shot although the club has a length of 120 cm or more, preferably 125 cm or more.

Abstract: A golf club head with an internal power shaft that extends along the target line. In a high volume club head embodiment above 250 cm..sup.3, constructed of a low modulus alloy compared to stainless steel, the power shaft has a preload, or static compression, to increase the modulus of elasticity of the head and ball striking face. This preload technique is expanded in another embodiment into a semi-customized line of golf club woods, where the club head modulus of elasticity increases with the golfer's club head speed by progressively increasing preload in the club head line. The power shaft is press-fitted into the rear of the ball striking face to reduce bonding and welding difficulties in joining the power shaft to the ball striking face. The modulus of the face wall and the power shaft is enhanced by casting or welding the sole plate of the club head along an axial extent directly to the outer surface of the power shaft thereby increasing its columnar strength.

Abstract: A head for a golf club iron is disclosed that provides a top planar surface which is substantially uniform width from toe to heel and shall support an indicia perpendicular to the longitudinal axis and parallel to the intended path of the ball. The indicia and the planar striking surface of the club face define an angle between them equal to the preselected loft angle for the planar striking surface plus 90.degree., and such a relationship holds true for each club in a set. When the club is in the correct address position, such a relationship shall provide the golfer with dual axial alignment to insure the planar striking surface is perpendicular to the intended target line of the ball and the loft angle of the planar striking surface, with respect to the ball, matches the preselected loft angle. The golfer will use the indicia as a sighting aid when addressing the ball, so the club head may be adjusted to ensure correct direction and loft.

Abstract: A set of iron golf clubs permitting to hit a ball correctly with a positive ball catching and less pulling even when used by any average golfer, in which as the club number ascends, the center distance L between the axis 20 of club shaft and the center C of club head impact face 2 is gradually longer and the weight distributed on the heel 4 is gradually smaller while the weight distributed on the toe 3 is gradually larger.

Abstract: A golf club head for an iron has a dual sole comprising first and second discontinuous surfaces which intersect along a diagonal line between the leading edge of the head at the toe and an intermediate point on a trailing edge of the head. The soles progressively taper from the long irons to the short irons so that the intersection of the diagonal line with the trailing edge is progressively closer to the toe. The head construction reduces weight in the toe and ground contact in the toe area, and moves the center of resistance toward the heel of the club. This reduces head droop and the tendency of the toe to dig into the ground, and, minimizes opening of the face at impact.

Abstract: A golf club metal wood head made of lighter weight material than stainless steel, such as aluminum alloy, has a front wall with an outer striking face, an upper wall, a lower wall, a rear wall, a heel and a toe, and an internal cavity milled out through a wall of the head to selected dimensions to provide a selected front wall thickness, and a varying wall thickness around the remainder of the head to provide a selected perimeter weighting to the head. The front wall is made significantly thicker than in conventional heads.

Abstract: A set of golf clubs including a number of golf clubs which are numbered serially and having progressively increasing loft angles from long irons to short irons. In a cross section of a number of face line grooves arranged on a striking face, the striking face and a groove slope face form a corner portion having a cross-sectional angle which decreases gradually from the long irons to the short irons.

Abstract: Methods of making a set of golf clubs and shafts that are matched according to vibration frequency are disclosed. The methods may include a random selection of shafts from a stock of raw shafts, wherein the vibration frequency of each shaft is determined and then each shaft is assigned a club head number. By determining conversion values based on desired and actual club head weights for each shaft and by determining a value between a desired and measured frequency of each shaft, a total frequency conversion value may be obtained. The total frequency conversion value may then be used to determine an amount to trim each shaft and thereby linearly match each shaft in the set based on vibration frequency and an increase in club head number.

Abstract: A head for a golf club iron is disclosed that provides a top planar surface for triaxial alignment of a planar striking surface substantially perpendicular to the intended path of the ball, so that the loft angle of the planar striking surface with respect to the ball matches a preselected loft angle, and so that the lie of the club from toe to heel is balanced. The top planar surface and the planar striking surface of the club face define an angle between them equal to the preselected loft angle for the planar striking surface plus 90.degree.. The back surface of the club intersects the top planar surface to define a sighting edge that is rearwardly extended from the trailing top edge of the club face for alignment of the club face perpendicular to the intended path of the ball. The top planar surface is of substantially uniform width from toe to heel and the loft and lie of the club are adjusted by holding the top planar surface horizontal.

Abstract: A new golf club face design is disclosed in which different regions of grooves are provided in the vertical direction of the club face to impose different roll/bite characteristics on a golf ball depending on where the golf ball contacts the club face. In one embodiment, the golf club face has three characteristic regions of different types of grooves in the vertical direction of the club face. Different irons within the golf club set can also have different characteristic grooves in the three defined regions of the club face.

Abstract: A golf club providing improved control of distance and direction of a golf ball impacted by the club includes a resilient insert having a controlled rebound factor fitted into a recess provided in the face of the club head. In the preferred embodiment, the insert comprises one or more thin laminations, each having an intrinsic rebound factor and thickness selected to yield in combination an overall composite ball-impacting rebound factor that may be varied over a relatively wide range of rebound factors, preferably which are an approximately linear function of desired travel range of the impacted ball. Also in the preferred embodiment, the inserts are made of a material in which the hardness may be varied somewhat independently from rebound factor, thus allowing construction of a club having a desired ball-impacting feel as well as selected rebound factor.

Abstract: An improved set of golf clubs wherein the face of the head of each golf club is offset relative to the central axis of the shaft of the golf club so as to provide a more consistent swing for golfers. The golf club set comprises progressively numbered wood clubs and progressively numbered iron clubs inclusive of a pitching wedge and sand wedge. The wood clubs and iron clubs each have correspondingly, progressively shorter and less flexible club shafts as well as correspondingly, progressively larger loft angles between the club faces and the shaft axes beginning with the lowest numbered club and progressing through the highest numbered club. The improvement comprises a set of wood and iron clubs each having at least one to seven and one to ten groups of face progression values, respectively. Each group of face progression values varies in accordance with each other group.

Abstract: In a golf club set, a face plate made of a material that is lower in specific gravity and elastic modulus than that of a head body of each golf club, is mounted on a face portion of the head body. The thicknesses of the face plates of the golf clubs increase in the order of the golf clubs of large club numbers to those of small club numbers. Further, a through hole may be formed through the head body of each golf club to extend from a face portion thereof to a back portion thereof. In this case, the face plate is mounted on the face portion of the head body, while closing the through hole.

Abstract: A mechanical locking device for use in attaching the shaft of a golf club to the clubhead. An angle is cast inside the hosel at the base of the hosel bore. The tip of the shaft is cut at an angle matching the angle at the bottom of the hosel bore, such that when the shaft is inserted into the bore, there is no room for lateral movement or twisting of the shaft. This device eliminates the risk that the shaft will separate from the clubhead if the epoxy cement bond should break.

Abstract: An iron golf club set comprising a plurality of clubs with varying lofts and insets, in which the inset of each club is equal to or less than the inset for the next club in the set with less club loft and there are at least three different insets within the set. In a preferred embodiment, the plurality of clubs have offsets, in which the offset of each club is equal to or less than the offset for the next club in the set with less club loft and there are at least three different offsets within the set.

Abstract: A golf club or set of golf clubs include a sole having three surfaces: a positive bounce surface, a trailing sole surface and a crescent surface therebetween. The crescent surface has a generally straight front boundary and a curved rear boundary. Moreover, the crescent surface has a bounce angle such that there is a contact point substantially in the center of the rear boundary of the crescent surface.

Abstract: A golf club iron comprising a shaft, a head having a sole, a toe end, and a heel end. The head comprises a striking face and a cavity in the back portion. A vibration dampening ramp bar extends from the lower edge of the cavity and terminates at its lower end short of the upper edge of the cavity with the ramp bar being offset from the center of gravity of the club head. In a set of irons, the distance between the center of the lower end of the ramp and the toe of the iron increases as the loft of the club head increases.

Abstract: An improved golf club head and set of clubs using progressively sized heads. The club head, of the sort generally referred to as "irons" has the usual striking and opposed back faces, an upper edge, a sole, a heel adjacent to the hosel and a toe opposite the heel. A slot of selected depth is provided across the back, extending diagonally from the upper heel area to the lower toe portion, so as to provide a thin central region and two thicker regions at the intersection of toe and upper edge and at the intersection of heel and sole. The resulting head has a diagonal balance along a line extending along the major axis of the normal elliptical pattern of ball impacts against the striking face, which results in a larger and more desirably oriented "sweet spot".

Abstract: Each iron in a golf club set is made to have a more consistant distance spectrum across its club face. This is done by deadening its sweet spot area so that the distance achieved with an on center hit is less, thereby making a center hit and an off center hit more nearly the same. The consistency of the average golfer is thereby improved, leading to lower scores and more enjoyable sport. The "dead center" irons may have their face angles, or loft, reduced to increase overall distance in order to compensate for the reduced distance reaction of the center hit, in order that the irons of a specific type or number will retain their traditional distance reaction.

Abstract: A set of iron golf club heads for correction of each tendency to hook balls for short irons, and to slice balls for long irons respectively. As the number of the iron golf club head increases, the back of each head body is shifted crosswise away from the neck relative to the face. Thus, as the number of the iron golf club head increases, the center of gravity of each head body is generally shifted crosswise away from the neck as well. Particularly, a position of a middle point M of the face of the 5th iron golf club head is approximately consistent with that of the center of gravity with respect to the lateral direction. Owing to the above position-settings of the center of gravity, balls are given slicing rotation for short irons, while balls are given hooking rotation for long irons, thereby decreasing either a habitual hooking or slicing tendency.