Golf Ball

The present application claims the benefit of U.S. Provisional Patent Application No. 63/651,925, filed May 24, 2024, the entire disclosure of which is incorporated by reference herein.

This disclosure generally relates to a golf ball, and is more particularly related to aerodynamic performance attributes and construction parameters of a golf ball.

It is generally known that aerodynamic characteristics of a golf ball have significant impact on the flight of the golf ball, and thus the overall performance of the golf ball. In one aspect, aerodynamic characteristics or properties of a golf ball are influenced by the dimple pattern of the golf ball. It is also generally known that the construction of the golf ball, including materials, size, compression, coefficient of restitution, and other parameters, also has a significant impact on the flight of the golf ball.

It would be desirable to provide improved aerodynamic performance attributes and golf ball construction parameters that generally provide greater control of the golf ball flight and distance.

In various aspects disclosed herein, a golf ball is provided that can have particular performance attributes or characteristics. In other aspects, certain aerodynamic performance or characteristics can be paired or matched with particular golf ball constructions, thereby resulting in a particular golf ball behavior. In certain aspects, a particular golf ball dimple pattern or dimple parameters are enumerated herein that result in a particular aerodynamic profile having at least one of the disclosed aerodynamic performance attributes or characteristics.

In one aspect, a golf ball is disclosed that comprises at least a core and a cover. The golf ball can include at least one additional layer besides a core and a cover. In one aspect, the golf ball can include a multi-layered core, a multi-layered cover, and/or a multi-layered casing/intermediate layer. Further details of the golf ball construction are provided herein.

In one aspect, the golf ball can have a weight of 1.600 ounces-1.620 ounces. In one aspect, the golf ball can have a weight of less than 1.600 ounces, or greater than 1.620 ounces. One of ordinary skill in the art would understand that the weight of the golf ball can vary.

In one aspect, the golf ball has a diameter of 1.680 inches-1.700 inches. In one aspect, the golf ball can have a diameter of greater than 1.700 inches, or less than 1.680 inches. One of ordinary skill in the art would understand that the size or diameter of the golf ball can vary.

The cover can comprise a plurality of dimples arranged in a dimple pattern that has or exhibits a series of drag coefficients (C) and lift coefficients (C) across a variety of Reynolds numbers and spin ratios.

The present disclosure provides various exemplary patterns that exhibit the presently disclosed aerodynamic performance attributes or characteristics.

Various other exemplary dimple patterns and/or dimple parameters are provided herein.

As disclosed herein, a golf ball that exhibits the presently disclosed aerodynamic performance attributes or characteristics can be associated with a golf ball having various golf ball construction parameters. The golf ball construction can be classified or characterized generally according to certain performance characteristics, such as compression, coefficient of restitution, initial velocity, etc. Each of these parameters is described in more detail herein.

In one aspect, the drag coefficient has the following range: C≤0.230 at a Reynolds number of 220,000 and a spin ratio of 0.070; the drag coefficient has the following range: C≤0.230 at a Reynolds number of 160,000 and a spin ratio of 0.095; and the drag coefficient has the following range: C≤0.230 at a Reynolds number of 120,000 and a spin ratio of 0.100.

In one aspect, the golf ball can have a dimple pattern that has an integrated drag area (DA) defined by:

where C(Re) is established at a launch condition of a golf ball speed of 182.0 mph, a launch angle of 10.0 degrees, and a spin rate of 2,700 rpm. In one aspect, the integrated drag area can be defined such that: DA≤14,000.

In one aspect, the lift coefficient has the following values or range of values: C>0.125 at a Reynolds number of 240,000 and spin ratio of 0.060, and C<0.180 at a Reynolds number of 185,000 and a spin ratio of 0.105.

In one aspect, the lift coefficient has the following values or range of values: C>0.120 at a Reynolds number of 240,000 and spin ratio of 0.060, and C<0.175 at a Reynolds number of 185,000 and a spin ratio of 0.105.

In one aspect, the lift coefficient has the following values or range of values: C>0.130 at a Reynolds number of 240,000 and spin ratio of 0.060, and C<0.190 at a Reynolds number of 185,000 and a spin ratio of 0.105.

In one aspect, the lift coefficient has the following values or range of values: C>0.115 at a Reynolds number of 240,000 and spin ratio of 0.060, and C<0.165 at a Reynolds number of 185,000 and a spin ratio of 0.105.

In one particular aspect, the drag and lift coefficients can have a particular relationship. This particular relationship can be associated with or dictate the flight window of the golf ball. In one aspect, this particular relationship can be defined at a Reynolds number of 225,000, and a spin ratio of 0.070. In one aspect, the drag coefficient and the lift coefficient can have the following relationship: 1.350≤C/C≤1.950. Various other details regarding the relationship between the drag and lift coefficients are provided herein.

In one aspect, the golf ball can have a compression of less than 60. In one aspect, the golf ball can have a compression of 60-80. In one aspect, the golf ball can have a compression of 80-100. In one aspect, the golf ball can have a compression of greater than 100. One of ordinary skill in the art would understand that the compression can vary.

In one aspect, the golf ball has a coefficient of restitution of less than 0.795. In one aspect, the COR of the golf ball can be less than 0.790. In one aspect, the COR of the golf ball can be less than 0.775. In one aspect, the COR of the golf ball can be less than 0.750. One of ordinary skill in the art would understand that the coefficient of restitution can vary.

In one aspect, the golf ball can have a compression of less than 60, and a COR of less than 0.785. In one aspect, the golf ball can have a compression of at least 60 and less than 80, and a COR of less than 0.775. In one aspect, the golf ball can have a compression of at least 80 and less than 100, and a COR of less than 0.755. In one aspect, the golf ball can have a compression of at least 100, and a COR of less than 0.725.

In one aspect, the golf ball can have an initial velocity of no greater than 252 feet/second. In one aspect, the golf ball can have an initial velocity of no greater than 250 feet/second. In one aspect, the golf ball can have an initial velocity of no greater than 248 feet/second. In one aspect, the golf ball can have an initial velocity of no greater than 245 feet/second. In one aspect, the golf ball can have an initial velocity of no greater than 240 feet/second. In one aspect, the golf ball can have an initial velocity of no greater than 235 feet/second. In one aspect, the golf ball can have an initial velocity of 225-245 feet/second. In one aspect, the golf ball can have an initial velocity of 230-245 feet/second. In one aspect, the golf ball can have an initial velocity of 220-240 feet/second. One of ordinary skill in the art would understand that the initial velocity can vary.

In one aspect, the golf ball core can have a weight of at least 1.115 ounces. In one aspect, the golf ball core can have a weight of at least 1.220 ounces. In one aspect, the golf ball core can have a weight of at least 1.225 ounces. In one aspect, the golf ball core can have a weight of at least 1.320 ounces.

In one aspect, the golf ball core can have a diameter of at least 1.500 inches. In one aspect, the golf ball core can have a diameter of at least 1.525 inches. In one aspect, the golf ball core can have a diameter of at least 1.545 inches. In one aspect, the golf ball core can have a diameter of at least 1.570 inches.

In one aspect, the golf ball core can have a coefficient of restitution of less than 0.725. In one aspect, the golf ball core can have a coefficient of restitution of less than 0.745. In one aspect, the golf ball core can have a coefficient of restitution of less than 0.755. In one aspect, the golf ball core can have a coefficient of restitution of less than 0.765. In one aspect, the golf ball core can have a coefficient of restitution of less than 0.775. In one aspect, the golf ball core can have a coefficient of restitution of less than 0.785. In one aspect, the golf ball core can have a coefficient of restitution of 0.725-0.765. In one aspect, the golf ball core can have a coefficient of restitution of 0.735-0.780.

In one particular aspect, a golf ball is provided that includes at least a core and a cover. The cover comprises a plurality of dimples arranged in a dimple pattern having a drag coefficient (C) and a lift coefficient (C), such that: C≤0.230 at a Reynolds number of 220,000 and a spin ratio of 0.070, C≤0.230 at a Reynolds number of 160,000 and a spin ratio of 0.095, and C≤0.230 at a Reynolds number of 120,000 and a spin ratio of 0.100. The dimple pattern also has an integrated drag area (DA) defined by:

where C(Re) is established at a launch condition of a golf ball speed of 182.0 mph, a launch angle of 10.0 degrees, and a spin rate of 2,700 rpm, such that DA≤14,000. The golf ball has a weight of 1.600 ounces-1.620 ounces and a diameter of 1.680 inches-1.700 inches. The core has a weight (W) of at least 1.245 ounces and a diameter (D) of at least 1.525 inches. Furthermore, (i) the golf ball has a compression that is less than 60, and the golf ball coefficient of restitution is less than 0.785; or (ii) the golf ball has a compression of at least 60 and less than 80, and the golf ball coefficient of restitution (COR) is less than 0.775; or (iii) the golf ball has a compression of at least 80 and less than 100, and the golf ball coefficient of restitution (COR) is less than 0.755; or (iv) the golf ball has a compression that is at least 100, and the golf ball coefficient of restitution (COR) is less than 0.725. In one particular aspect, C≤0.225 at a Reynolds number of 220,000 and a spin ratio of 0.070; C≤0.225 at a Reynolds number of 160,000 and a spin ratio of 0.095; and C≤0.225 at a Reynolds number of 120,000 and a spin ratio of 0.100. The golf ball can exhibit a speed factor(S) defined by the following equation: S=902.67+814.63 (COR)-5.44 IV, where (COR) is the golf ball coefficient of restitution, and (IV) is the golf ball initial velocity (feet/second), and wherein the Speed Factor(S) is less than 177. In one aspect, the Speed Factor is less than 176. In another aspect, the Speed Factor is less than 175. In one aspect, the core weight (W) is at least 1.260 ounces and the core diameter (D) is at least 1.530 inches. In another aspect, the core weight (W) is at least 1.275 ounces and the core diameter (D core) is at least 1.545 inches. In another aspect, the core weight (W) is at least 1.300 ounces and the core diameter (D) is at least 1.545 inches. The golf ball can exhibit a Flight Factor (F) defined by the following equation:

in one aspect, where (IV) is the golf ball initial velocity (feet/second) and (COR) is the core coefficient of restitution. In one aspect, the Flight Factor (F) can be at least 120. The integrated drag area (DA) can be defined such that DA≤13,750; or DA≤13,500; or DA≤13,250. A coefficient of restitution of the core can be no greater than 0.740, in one aspect. In another aspect, a coefficient of restitution of the core is no greater than 0.700. In yet another aspect, a coefficient of restitution of the core is no greater than 0.670. The drag coefficient (C) and the lift coefficient (C) at a Reynolds number of 225,000, and spin ratio of 0.070 can have the following relationships: (i) 1.350≤C/C<1.550; or (ii) 1.550≤C/C<1.750; or (iii) 1.750≤C/C≤1.950.

Additional features and aspects of the present disclosure are described in further detail herein.

The dimples on a golf ball are used to adjust or modify the aerodynamic characteristics of a golf ball and, therefore, the dimple patterns, shape, volume, and various other dimple properties or characteristics can be designed in order to modify the overall flight of a golf ball. Determining specific dimple arrangements and dimple shapes that result in desired aerodynamic properties can involve the direct measurement of aerodynamic characteristics. These aerodynamic characteristics define the forces acting upon the golf ball throughout flight. The term “dimple” can include any texturizing on the surface of a golf ball, e.g., depressions and projections.

Aerodynamic forces acting on a golf ball are typically resolved into orthogonal components of lift and drag. Lift is defined as the aerodynamic force component acting perpendicular to the flight path. It results from a difference in pressure that is created by a distortion in the air flow that results from the back spin of the golf ball. A boundary layer forms at the stagnation point of the ball, B, then grows and separates at points Sand S, as shown in. Due to the ball backspin, the top of the ball moves in the direction of the airflow, which delays the separation of the boundary layer. In contrast, the bottom of the ball moves against the direction of airflow, thus advancing the separation of the boundary layer at the bottom of the ball. Therefore, the position of separation of the boundary layer at the top of the ball, S, is further back than the position of separation of the boundary layer at the bottom of the ball, S. This asymmetrical separation creates a downward deflection in the flow pattern, requiring the air over the top of the ball to move faster and, thus, have lower pressure than the air underneath the ball.

Drag is defined as the aerodynamic force component acting parallel to the golf ball's flight direction. As the ball travels through the air, the air surrounding the ball has different velocities and, accordingly, different pressures. The air exerts maximum pressure at the stagnation point, B, on the front of the ball, as shown in. The air then flows over the sides toward the back of the golf ball and separates from the surface of the golf ball at points Sand S, leaving a large turbulent flow area with low pressure, i.e., the wake. The difference between the high pressure in front of the golf ball and the low pressure in the wake behind the golf ball reduces the speed and acts as the primary source of drag for a golf ball.

The aerodynamic forces acting on a golf ball in flight are disclosed in Equation 1 and illustrated in:

where F=total force acting on the ball; F=lift force; F=drag force; and F=gravity force.

The lift force (F) is the component of the aerodynamic force acting in a direction dictated by the cross product of the spin vector and the velocity vector. The drag force (F) is the component of the aerodynamic force acting in a direction that is directly opposite the velocity vector. The lift and drag forces of Equation 1 are calculated in Equations 2 and 3, respectively:

where ρ=density of air (slugs/ft); A=projected area of the ball (ft)((π/4)D); D=golf ball diameter (ft); V=ball velocity (ft/s); C=dimensionless lift coefficient; and C=dimensionless drag coefficient.

Lift and drag coefficients are used to quantify the force imparted to a golf ball in flight and are dependent on air density, air viscosity, ball speed, and spin rate; the influence of all these parameters may be captured by two dimensionless parameters: spin ratio (SR) and Reynolds number (Re). Spin ratio is the rotational surface speed of the ball divided by ball velocity. Reynolds number quantifies the ratio of inertial to viscous forces acting on the golf ball moving through air. SR and Re are calculated in Equations 4 and 5 below:

where ω=ball rotation rate (radians/s)(2π(RPS)); RPS=golf ball rotation rate (revolution/s); V=ball velocity (ft/s); D=ball diameter (ft); ρ=air density (slugs/ft); and μ=absolute viscosity of air (lb/ft-s).

There are a number of suitable methods for determining the lift and drag coefficients for a given range of spin rate and Reynolds number, which include the use of indoor test ranges with ballistic screen technology. U.S. Pat. No. 5,682,230, the entire disclosure of which is incorporated by reference herein, teaches the use of a series of ballistic screens to acquire lift and drag coefficients. U.S. Pat. Nos. 6,186,002, 6,285,445, and 6,729,976, also incorporated in their entirety by reference herein, disclose methods for determining lift and drag coefficients for a given range of velocities and spin rates using an indoor test range, wherein the values for Cand Care related to spin rates and Reynolds numbers for each shot. One skilled in the art of golf ball aerodynamics testing could readily determine the lift and drag coefficients through the use of an indoor test range.

One of ordinary skill in the art will recognize that the desired aerodynamic performance, characterized by the coefficients of lift and drag, may be achieved by combining various elements of dimple pattern characterization including but not limited to total dimple count, total surface coverage, total dimple volume, number of different dimple diameters, average dimple diameter, range of dimple diameters, dimple plan shape, dimple profile, and underlying pattern geometry to generate exemplary dimple pattern categories.

Determination of the drag coefficient (C) is necessary to calculate the drag force acting on a golf ball at a given instant in flight, and for a golf ball of a given diameter traveling at a given speed through air with a given density, a higher drag coefficient indicates a greater drag force acting on that golf ball. One can therefore refer to a dimple configuration that induces an overall greater drag force magnitude by identifying higher values of Cat given Reynolds numbers and spin ratios. It follows, then, that a pattern with overall higher values of Cmay have a shorter flight distance.

There are a number of suitable methods for determining the lift and drag coefficients for a given range of spin rates and Reynolds numbers, including the use of indoor test ranges. U.S. Pat. Nos. 6,186,002 and 6,285,445, the entireties of which are each incorporated by reference herein, disclose methods for determining lift and drag coefficients for a given range of velocities and spin rates using an indoor test range, wherein the values for Cand Care related to spin rates and Reynolds numbers for each shot. One skilled in the art of golf ball aerodynamics testing could readily determine the lift and drag coefficients through the use of an indoor test range.