Patent Application
20180028883
It is a goal for golfers to reduce the total number of swings needed to complete a round of golf, thus reducing their total score. To achieve that goal, it is generally desirable to for a golfer to have a ball fly a consistent distance when struck by the same golf club and, for some clubs, also to have that ball travel a long distance. For instance, when a golfer slightly mishits a golf ball, the golfer does not want the golf ball to fly a significantly different distance. At the same time, the golfer also does not want to have a significantly reduced overall distance every time the golfer strikes the ball, even when the golfer strikes the ball in the “sweet spot” of the golf club.
In one aspect, the technology relates to an iron-type golf club head, having: a club head body having a back portion and a striking face; a cradle attached to an internal surface of the back portion; and an elastomer extending from the cradle towards a rear surface of the striking face. In an embodiment, the iron-type golf club head further includes an adjustment mechanism operatively connected to the elastomer and the back portion, wherein the adjustment mechanism is configured to adjust a compression of the elastomer. In another embodiment, the adjustment mechanism includes a screw having a screw drive at least partially external to the club head body and wherein the screw is engaged with the cradle. In yet another embodiment, the back portion includes a threaded hole for receiving the screw such that turning of the screw adjusts the compression of the elastomer. In still another embodiment, the elastomer displays an elastic modulus of about 1 to about 40 gigapascals (GPa).
In another embodiment of the above aspect, the iron-type golf club head further includes a sole connecting the back portion to the striking face, wherein the sole at least partially defines a channel. In an embodiment, the cradle encompasses at least 25% of a volume of the elastomer. In another embodiment, the cradle is formed to substantially match a shape of a rear portion of the elastomer. In yet another embodiment, the iron-type golf club head further includes a securing structure attached to the rear surface of the striking face, the securing structure configured to secure the elastomer to a position on the rear surface of the striking face.
In another aspect, the technology relates to an iron-type golf club head having: a club head body having a back portion and a striking face; an elastomer in contact with a rear surface of the striking face; and an adjustment mechanism operatively connected to the elastomer, wherein the adjustment mechanism is configured to adjust a compression of the elastomer. In an embodiment, the adjustment mechanism includes a screw having a screw drive at least partially external to the club head body and an interface operatively connected to the elastomer. In another embodiment, the back portion includes a threaded hole for receiving the screw such that turning of the screw adjusts the compression of the elastomer. In yet another embodiment, the interface includes a cradle at least partially encompassing the elastomer, wherein the cradle is in contact with the adjustment mechanism. In still another embodiment, the elastomer displays an elastic modulus of about 1 to about 50 GPa.
In another embodiment of the above aspect, the elastomer displays an elastic modulus of about 4 to about 15 GPa. In an embodiment, the back portion further includes a cradle at least partially encompassing the elastomer. In another embodiment, a portion of the striking face in contact with the elastomer has a thickness different from a thickness of another portion of the striking face. In yet another embodiment, the iron-type golf club head further includes a securing structure attached to the rear surface of the striking face, the securing structure configured to secure the elastomer to a position on the rear surface of the striking face.
In another aspect, the technology relates to a kit for assembling an iron-type golf club, the kit includes: a club head body having a back portion and a striking face; an elastomer having a first portion in contact with a rear surface of the striking face and a second portion in contact with a cradle; a set of differently weighted adjustment drivers; and an adjustment receiver incorporated in the back portion, wherein the adjustment mechanism is configured to receive an adjustment driver that, when manipulated, adjusts a compression of the elastomer between the back portion and the striking face. In an embodiment, the set of differently weighted adjustment drivers includes a set of differently weighted screws, and wherein the adjustment receiver is a threaded hole extending through the back portion.
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
Non-limiting and non-exhaustive examples are described with reference to the following Figures.
The technologies described herein contemplate an iron-type golf club head that incorporates an elastomer element to promote more uniform ball speed across the striking face of the golf club. Traditional thin-faced iron-type golf clubs generally produce less uniform launch velocities across the striking face due to increased compliance at the geometric center of the striking face. For example, when a golf club strikes a golf ball, the striking face of the club deflects and then springs forward, accelerating the golf ball off the striking face. While such a design may lead to large flight distances for a golf ball when struck in the center of the face, any off-center strike of golf ball causes significant losses in flight distance of the golf ball. In comparison, an extremely thick face causes more uniform ball flight regardless of impact location, but a significant loss in launch velocities. The present technology incorporates an elastomer element between a back portion of the hollow iron and the rear surface of the striking face. By including the elastomer element, the magnitude of the launch velocity may be reduced for strikes at the center of the face while improving uniformity of launch velocities across the striking face. In some examples, the compression of the elastomer element between the back portion and the striking face may also be adjustable to allow for a golfer or golf club fitting professional to alter the deflection of the striking face when striking a golf ball.
A front portion 103 of the elastomer element 102 contacts the rear surface 119 of the striking face 118. The front portion 103 of the elastomer element 102 may be held in place on the rear surface 119 of the striking face 118 by a securing structure, such as flange 110. The flange 110 protrudes from the rear surface 119 of the striking face 118 into the cavity 120. The flange 110 receives the front portion 103 of the elastomer element 102 to substantially prevent the elastomer element 102 from sliding along the rear surface 119 of the striking face 118. The flange 110 may partially or completely surround the front portion 103 of the elastomer element 102. Similar to the cradle 108, the flange 110 may be shaped to match the shape of the front portion 103 of the elastomer element 102 such that the surface of the front portion 103 of the elastomer element 102 is in contact with the interior surfaces of the flange 110. The flange 110 may be welded or otherwise attached to the rear surface 119 of the striking face 118. The flange 110 may also be cast or forged during the formation of the striking face 118. For instance, where the striking face 118 is a face insert, the flange 110 may be incorporated during the casting or forging process to make the face insert. In another example, the flange 110 and the striking face 118 may be machined from a thicker face plate. Alternative securing structures other than the flange 110 may also be used. For instance, two or more posts may be included on rear surface 119 of the striking face 118 around the perimeter of the front portion 103 of the elastomer element 102. As another example, an adhesive may be used to secure the elastomer element 102 to the rear surface 119 of the striking face 118. In other embodiments, no securing structure is utilized and the elastomer element 102 is generally held in place due to the compression of the elastomer element 102 between the cradle 108 and the rear surface 119 of the striking face 118.
In the example depicted in
The elasticity of the elastomer element 102 also affects the deflection of the striking face 118. For instance, a material with a lower elastic modulus allows for further deflection of the striking face 118, providing for higher maximum ball speeds but less uniformity of ball speeds. In contrast, a material with a higher elastic modulus further prevents deflection of the striking face 118, providing for lower maximum ball speeds but more uniformity of ball speeds. Different types of materials are discussed in further detail below with reference to Tables 2-3.
The golf club head 100 also includes a sole 105 having a sole channel 104 in between a front sole portion 114 and a rear sole portion 116. The sole channel 104 extends along the sole 105 of the golf club head 100 from a point near the heel to a point near the toe thereof. While depicted as being a hollow channel, the sole channel 104 may be filled or spanned by a plastic, rubber, polymer, or other material to prevent debris from entering the cavity 120. The sole channel 104 allows for additional deflection of the lower portion of the striking face 118. By allowing for further deflection of the lower portion of the striking face 118, increased ball speeds are achieved from ball strikes at lower portions of the striking face 118, such as ball strikes off the turf. Accordingly, the elastomer element 102 and the sole channel 104 in combination with one another provide for increased flight distance of a golf ball for turf strikes along with more uniform ball speeds across the striking face 118.
The golf club head 300 also includes an adjustment mechanism. The adjustment mechanism is configured to adjust the compression of the elastomer element 302 against the rear surface 319 of the striking face 318. In the embodiment depicted in
A higher compression of the elastomer element 302 against the rear surface 319 of the striking face 318 further restricts the deflection of the striking face 318. In turn, further restriction of the deflection causes more uniform ball speeds across the striking face 318. However, the restriction on deflection also lowers the maximum ball speed from the center of the striking face 318. By making the compression of the elastomer element 302 adjustable with the adjustment mechanism, the golfer or a golf-club-fitting professional may adjust the compression to fit the particular needs of the golfer. For example, a golfer that desires further maximum distance, but does not need uniform ball speed across the striking face 318, can reduce the initial set compression of the elastomer element 302 by loosening the threaded element 330. In contrast, a golfer that desires uniform ball speed across the striking face 318 can tighten the threaded element 330 to increase the initial set compression of the elastomer element 302.
While the adjustment mechanism is depicted as including a threaded element 330 and a threaded through-hole in
The golf club head 300 also includes a sole channel 304 between a front sole portion 314 and a rear sole portion 316, similar to the sole channel 104 discussed above with reference to
The golf club head 300 may also be created or sold as a kit. In the example depicted where the adjustment mechanism is a threaded element 330, such as a screw, the kit may include a plurality of threaded elements 330. Each of the threaded elements 330 may have a different weight, such that the golfer can select the desired weight. For example, one golfer may prefer an overall lighter weight for the head of an iron, while another golfer may prefer a heavier weight. The plurality of threaded elements 330 may also each have different weight distributions. For instance, different threaded elements 330 may be configured so as to distribute, as desired, the weight of each threaded element 330 along a length thereof. The plurality of threaded elements 330 may also have differing lengths. By having differing lengths, each threaded elements 330 may have a maximum compression that it can apply to the elastomer element 302. For instance, a shorter threaded elements 330 may not be able to apply as much force onto the elastomer element 302 as a longer threaded elements 330, depending on the configuration of the adjustment receiver 306. The kit may also include a torque wrench for installing the threaded elements 330 into the adjustment receiver 306. The torque wrench may include preset settings corresponding to different compression or performance levels.
The tip of the screw 430 is in contact with a cradle 408A that holds a rear portion of the elastomer element 402. As the screw 430 is turned, the lateral movement of the screw 430 causes the cradle 408A to move towards or away from the striking face 418. Accordingly, in some examples, the screw 430 extends substantially orthogonal to the rear surface 419 of the striking face 418. Because the cradle 408A holds the rear portion of the elastomer element 402, movement of the cradle 408A causes a change in the compression of the elastomer element 402 against the rear surface 419 of the striking face 418. As such, the compression of the elastomer element 402 may be adjusted by turning the screw 430 via screw drive 432, similar to manipulation of the threaded element 330 in golf club head 300 depicted in
The size of the cradle 408C may be selected based on the desired ball speed properties. For instance, the cradle 408C may encompass approximately 25% or more of the volume of the elastomer element 402, as shown in
The connection between the cradle 408C and the adjustment driver 430 can also be seen more clearly in
While the golf club heads 400A and 400C are depicted with a continuous sole 414 rather than a sole channel like the golf club head 300 of
Simulated results of different types of golf club heads further demonstrate ball speed uniformity across the face of the golf club heads including an elastomer element. Table 1 indicates ball speed retention across the face of a golf club head for several different example golf club heads. Example 1 is a baseline hollow iron having a 2.1 mm face thickness with a sole channel. Example 2 is a hollow iron with a 2.1 mm face with a rigid rod extending from the back portion to the striking face, also including a sole channel. Example 3 is a hollow iron with a striking face having a thick center (6.1 mm) and a thin perimeter (2.1 mm), also having a sole channel. Example 4 is a golf club head having an elastomer element similar to golf club head 100 depicted in
From the results in Table 1, the golf club head with the elastomer (Example 4) displays a relatively high ball speed from the center of the face, while also providing a reduced loss of ball speed from strikes near the toe or the heel of the golf club.
In addition, as mentioned above, the type of material utilized for any of the elastomer elements discussed herein has an effect on the displacement of the striking face. For instance, an elastomer element with a greater elastic modulus will resist compression and thus deflection of the striking face, leading to lower ball speeds. For example, for a golf club head similar to golf club head 400A, Table 2 indicates ball speeds achieved from using materials with different elasticity properties. All ball speeds were the result of strikes at the center of the face.
From the results in Table 2, a selection of material for the elastomer element can be used to fine tune the performance of the golf club. Any of the materials listed in Table 2 are acceptable for use in forming an elastomer element to be used in the present technology.
The different types of materials also have effect on the ball speed retention across the striking face. For example, for a golf club head similar to golf club head 400A, Table 3 indicates ball speeds achieved across the striking face from heel to toe for the different materials used as the elastomer element. The materials referenced in Table 3 are the same materials from Table 2. All speeds in Table 3 are in mph.
From the results in Table 3, materials having a higher elastic modulus provide for better ball speed retention across the striking face, but lose maximum ball speed for impacts at the center of the face. For some applications, a range of elastic moduli for the elastomer element from about 4 to about 15 GPa may be used. In other applications, a range of elastic moduli for the elastomer element from about 1 to about 40 or about 50 GPa may be used.
As mentioned above with reference to
San Diego Plastics, Inc. of National City, Calif. offers several plastics having elastic moduli ranging from 2.6 GPa to 13 GPa that would all be acceptable for use. The plastics also have yield strengths that are also acceptable for use in the golf club heads discussed herein. Table 4 lists several materials offered by San Diego Plastics and their respective elastic modulus and yield strength values.
The inclusion of an elastomer element also provide benefits in durability for the club face by reducing stress values displayed by the striking face upon impact with a golf ball.
Although specific embodiments and aspects were described herein and specific examples were provided, the scope of the invention is not limited to those specific embodiments and examples. One skilled in the art will recognize other embodiments or improvements that are within the scope and spirit of the present invention. Therefore, the specific structure, acts, or media are disclosed only as illustrative embodiments. The scope of the invention is defined by the following claims and any equivalents therein.
