Patent Application
20240238657
The present invention is directed to a golf tee having a golf ball support and a stem, the support having a modified concave upper surface. The upper concave surface is configured to reduce the support interference angle.
During play, a portion of the stem is inserted into the course surface (e.g., tee box surface, soil, sand), at an angle substantially perpendicular to the course surface and at a depth sufficient to allow the golf tee to support or “tee up” a golf ball. When teed, the golf ball nests within a support recess defined by the modified concave upper surface.
When a player strikes the supported golf ball with the striking surface of a golf club head, the reduced interference angle results in less friction between the ball and support, increases the transfer of energy and momentum from the golf club head to the golf ball, and reduces undesirable golf rotation.
The sport of golf is played on a course consisting of multiple holes, each hole having a teeing area, fairway, and a putting green. At the start of play for each hole, the player uses a golf club to strike a golf ball supported or elevated from the playing surface (commonly referred to as a “tee box”) using a golf tee; thereafter, continuously striking the ball using clubs of varying types (drivers, woods, irons, putters, and the like), until the ball is ultimately holed on the putting green.
The United States Golf Association Rules of Golf requires tees be (1) a device designed to raise the ball off the ground, and not: (2) longer than 4 inches (101.6 mm), (3) designed or manufactured in such a way that it could indicate line of play, (4) unduly influence the movement of the ball, or (5) otherwise assist the player in making a stroke or in his play. (See, USGA Equipment Rules, 2019 ed., Rule 6.2).
Conventional golf tees generally consist of a crown or support adapted to receive a portion of the outer surface of a golf ball, and a stem having a tapered end distal from the crown. The tapered end is inserted vertically into the tee box surface to elevate or “tee” the ball.
As illustrated herein in the drawings, the vertical plane is defined by line AA and extends parallel to the long axis of the tee, and the horizontal plane is defined by line BB and extends parallel to the short axis of the tee.
Referring to
The upper concave surface 4 defines a spherical bowl-shaped recess into which at least a portion of the ball 5 extends when teed. The bowl-shaped recess of most commercially available tees is configured to support the ball 5 on a horizontally circular outer rim or ridge 4a (also commonly referred to as a “resting ridge”). With this concept the ball 5 rests solely on the upper surface ridge 4a of the concave upper surface 4.
The bowl-shaped recess has:
(1) a vertical height (h1) defined as the linear vertical distance between the ridge 4a and the recess bottom 4b (most distal point from ridge 4a); and
(2) a horizontal width (a1) representing the diameter of the bowl-shaped recess as defined by the horizontally circular outer ridge 4a.
Commercially available tees have recess width (a1) that is less than that of the diameter of a golf ball. The total horizontal width of a commercially available tee is typically about 0.44″. Per the 2019 USGA Equipment Rules, Rule 4.2, the diameter of a ball must not be less than 1.68″ (stated differently, a radius of not less than 0.84″).
The ball 5 has a spherical cap-shaped nesting portion 6 having a horizontal top base 6a and bottom point 6b (most distal point from the outer edge of the base 6a). The top base 6 has a horizontal base radius (ra). The recess width (a1) is equal to the diameter of the base 6a of the spherical cap (base diameter=2⋅(ra), (ra) being the horizontal linear distance between the ball bottom 6b and ridge 4a).
The vertical ball encroachment or displacement height (h2) is defined as the linear vertical distance between the horizontally circular outer ridge 4a and the ball's lowest vertical point 6b when the ball is nested in the bowl-shaped recess (teed for play).
It is commonly believed the conventional tee cup design is superior because it provides minimal resting surface area between the ball 5 and the tee 1 (namely, the surface area defined by where the ball contacts, and is supported by, the horizontally circular outer ridge 4a).
Referring to
The interference angle (α) is defined by the angle formed by the intersection of the tangent line (t1) and the recess top plane (y1) formed by the circle defined by the outer ridge 4a.
The value of the interference angle (α) is adjusted (αadj) using equation (1), wherein:
It has been found that a typical player surprisingly strikes a teed ball at an impact angle (i) of approximately −2° (i.e., by either on a downward swing or high on the ball relative the desired horizontal impact point) on the ball 5.
Therefore, a conventional tee having an interference (α) ˜22°, an impact angle (i) of −2° and a drive loft angle (l) of 10° (a typical drive has a loft angle of 9°-12.5°, the adjusted interference angle (αadj) will be 22°−(−2°−10°=14°
The typical ball encroachment height (h2) for a conventional tee 1 is approximately 0.03″. When the ball is struck the nested portion collides with the upper concave surface 4. The collision impacts the trajectory of the drive and imparts undesirable spin on the ball.
Further, when ball compression and elongation is accounted for, up to the entire vertical encroachment height (h2) of the ball may be undesirably launched into the concave upper surface 4. This results in a disadvantaged and inconsistent launch trajectory of the ball, as momentum is lost and ball spin increases, substantially impacting a player's ability to consistently hit the ball along a desired path and distance.
In summary, even when the impact of the ball is compensated by the loft angle of the club face, and assuming a player can strike the ball true to normal without any downward swing, the design of a conventional tee still results in a significant impact angle a moving ball must overcome.
Accordingly, there is a current need for an improved golf tee that avoids one or more of the disadvantages noted above.
It has been found the modified golf tee of the present invention affords benefits over tees known in the art. Such benefits include ease of use, decreased susceptibility to inducing ball spin when the ball is struck, decreased friction between the ball surface and tee crown, and simplified construction.
Specific embodiments and benefits are apparent from the detailed description provided herein. It should be understood, however, that the detailed description and specific examples, while indicating embodiments among those preferred, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
Referring to
The support 12 has a concave upper surface 16 which defines a concave-shaped recess into which at least a portion (defined below) of the ball 20 extends when teed. The recess can be generally described as having the shape of a cap of a sphere or spheroid.
The concave upper surface 16 terminates at an upper surface ridge 16a at the outer periphery of the recess, the concave upper surface 16 further having a recess bottom or low point 16b (the most distal point from ridge 16a). A horizontal washer or annulus-shaped upper surface 17 extends substantially horizontally from the upper surface ridge 16a to outer surface 12a of the support 12 (see
The recess has a vertical height (h3) defined as the linear vertical distance between the horizontally circular ridge 16a and the recess bottom 16b, and a horizontal width (a2) representing the linear width or diameter of the horizontally circular outer ridge 16a.
Referring to
The cap 22 has a horizontal top base 22a and bottom point 22b (most distal point from the base 22a).
The ball's cap-shaped nesting portion 22 has a vertical cap height (h4). The vertical cap height (h4) is defined as the linear vertical distance between the cap base 22a and ball bottom point 22b. When the ball 20 is teed, the ball cap 22 is completely nested in the recess defined by the tee concave upper surface 16. Stated differently, h3=h4.
The cap bottom 22b is the point of tangency for a ball tangent line (tb) which overlaps with a recess top plane (x) defined by the horizontal circle formed by the outer ridge 16a. The ball cap 22 is further defined as having horizontal base radius (rc) which is the linear horizontal distance between the ball bottom 22b and the outer edge of the base 22a.
As can be seen from
Referring to
The interference angle (β) is defined by the angle formed by the intersection of the tangent line (t2) and the recess top plane (y2) formed by the circle defined by the outer ridge 16a.
The adjusted value of the interference angle (βadj) is determined using equation (2), wherein:
As will be illustrated in the examples below and discussed in more detail, the unique relationship between the ball radius (rb) and recess radius (rr) of the recess formed by the concave recess surface 16 changes the interference angle (β). As the recess vertical height (h3) decreases, while maintaining the horizontal width (a2) of the horizontally circular outer ridge 16a, the interference angle (β) decreases. Reduction of the interference angle (β) reduces undesirable interference to the ball trajectory and spin as compared to conventional tees having greater interference angles (β).
Further, it has also been found when the recess radius (rr) of the recess formed by the concave recess surface 16 remains constant but the horizontal width (a2) of the horizontally circular outer ridge 16a is decreased, the interference angle (β) also decreases.
As illustrated in
However, the ball 5 will always be vertically statically supported at least in part by the upper concave surface ridge 4a because conventional thinking is a failure to so would result in the ball 5 being horizontally unstable within the cup of the crown. Stated differently, the construction of a conventional tee 1 is described as having a recess width (a1) equal to the diameter of the base of the spherical cap-shaped ball portion (based diameter=2⋅(ra)).
In contrast, the unique construction of the tee 10 described herein is described as statically supporting a ball 20 without the ball being entirely vertically supported by any portion of the upper surface ridge 16a. It should be noted the ball 20 may be supported horiztonally by the upper surface ridge 16a, preventing it from A comparison of the dimensions for the support recesses and spherical cap-shaped nested portions of the balls are summarized in Table 1 below.
The following examples are provided to further illustrate the present invention and are not meant to be limiting.
As illustrated in the examples below in Table 2, the examples assume a club loft angle of 10° and a player strike angle of −2°, as the recess vertical height (h2) decreases, so does the interference angle (β), until the adjusted interference angle (αadj, βadj) is at or less than 0°.
A tee having a horizontal width (a1) of 0.42″, a recess radius (rr) of 0.65″, and a ball radius (rb) of 0.84″ is examined for the relationship between the ball and recess radii (rb,rr) and nesting position of the ball within the concave recess.
Using the Intersection Cords Theorem one can calculate the vertical ball encroachment or displacement height (h2), defined as the linear vertical distance between the horizontally circular outer ridge 4a and the ball's lowest vertical point 6b when the ball is nested in the bowl-shaped recess (teed for play).
The vertical height of the bowl (h1) can be determined equation (3) below:
wherein:
The vertical ball encroachment or displacement height (h2) is calculated using equation (3), wherein CE=(h2) and ED=2⋅(rb)−(h2). Where (rb)=0.84″, (h2)=0.0267″.
The calculations above demonstrate (h2)<(h1) and therefore the ball bottom 6b does not contact the recess bottom 4b. The vertical gap between the bottom of the ball 6b and recess bottom 4b is calculated as (h1)−(h2)=0.0082″. If 0<(h2)<(h1) the ball bottom 6b will not contact the concave surface 4, but if (h2)=(h1) the ball bottom 6b and recess bottom 4b make contact and the ball will not contact the recess ridge 4a.
A comparison of tees having a horizontal width (a2) of 0.42″ and recess radii (rr) of 0.65″ and 1.0″, are calculated and compared.
The slope of the recess tangent line (t2) is calculated using the general equation for a circle (x2+y2=r2) and slope of a line (y=mx+b), wherein b=0, and r=½⋅(a2)=0.21″.
Table 3 below shows the calculated slope (m) of the tangent line for each recess radius (rr). The interference angle (β) is the inverse tangent (tan−1) of the slope of the recess tangent line (t2).
As Table 3 illustrates, as recess radius (rr) increases, the slope of the recess tangent line (t2) decreases as well as the interference angle (β).
A comparison of impact angles for tees having horizontal recess widths (a2) of 0.42″ and 0.32″, each with a recess radius (rr) of 1.0″ and 0.65″, are compared in Table 4 below.
As Table 4 illustrates, as recess radius (rr) increases as well as the recess width (a2), each independently reduces the interference angle (β).
| Number | Date | Country | |
|---|---|---|---|
| 63438748 | Jan 2023 | US |
