FR2627093A1 - GOLF BALL HAVING AN IMPROVED ALVEOL CONFIGURATION - Google Patents

Abstract

A golf ball having an improved cell configuration is disclosed. The golf ball has cells 10 each consisting of a first cavity 11 and a second cavity 13, the cavities being immediately adjacent to each other on a large circle of the ball; this dimple arrangement minimizes aerodynamic drag (air resistance) when the ball is played.

Description

The present invention relates to a golf ball having a configuration

of cells, or parts

  hollow, improved and more specifically

  a golf ball having a cell configuration that helps reduce aerodynamic drag when the ball is in flight. Figures 1 to 3 of the attached drawings

  illustrate the art prior to the present invention.

  An aerodynamic drag (air resistance) is exerted in a direction opposite to the direction of flight. The drag force encountered by the bale is influenced by the flow of air near the surface of the bale (the boundary layer) (Figures 1 and 1A). A strong drag is produced when the flow in the boundary layer is laminar at the point where the boundary layer separates

  the surface of the ball (the point of separation).

  To minimize drag, it is necessary to ensure that the flow in the boundary layer is turbulent at the point of separation (Figure 2) and that the ultimate separation point itself is located as far as possible towards the back of the ball (relative to the direction of flight). It has also been found that the thickness of the

  boundary layer is important because an increase in

  Thickness of the boundary layer produces a

  increased aerodynamic drag.

  The object of the present invention is to create a golf ball in which the surface pattern minimizes the thickness of the boundary layer and also produces separation and subsequent attachment.

  boundary layer on the bullet surface (Figure 3).

  It has been well established that such separation can occur on a planned discontinuity in the outer surface of the bullet, for example on the

  edge of a cell or a similar cavity.

  Accordingly, the present invention relates to a golf ball having a plurality of cells in its spherical outer surface, each cell comprising a first cavity and a second cavity, said first and second cavities being immediately adjacent to each other on

a big circle of the ball.

  Although it is not envisaged that the

  present invention be limited to a particular theory of

  In this case, it is considered that the edge of the first cavity triggers a separation of the boundary layer and that the flow of air on the second cavity produces

  an attachment of the boundary layer.

  In a first preferred embodiment of the present invention, the first and second

  cavity cavities have substantially the same dimensions

and the same configuration.

  Alternatively, the first cell cavity may have small dimensions and a small

  configuration with respect to the second cavity.

  In a second preferred embodiment of the present invention, the first cell cavity may comprise a ring, concentric with the second cavity, such that the cell has, in the assembly, an identical configuration regardless of the

direction of movement of the ball.

  Preferably, the cells may be distributed in a uniform and uniform pattern on the

  spherical outer surface of the ball.

  Other features and advantages of the invention will be highlighted later in the

  description, given by way of non-limiting example,

  with reference to the accompanying drawings, in which more particularly: Figure 4 is a plan view of a cell corresponding to a first preferred embodiment of the present invention - Figure 5 is a sectional view taken along line VV of Figure 4; FIG. 6 is a plan view of a cell corresponding to a second preferred embodiment of the present invention; FIG. 7 is a sectional view made according to the

line VII-VII of FIG.

  FIGS. 4 and 5 represent a cell having an outside diameter falling within the range of between 2 mm and 5 mm and a reentrant depth

  in the range of 0.1 mm to 0.3 mm. The alvéo-

  the 10 comprises two adjacent cavities 11 and 13, separated by a dividing portion 12. The dividing portion 12 has a height falling within the range

between 0.05 mm and 0.3 mm.

  Figures 6 and 7 show a cell

  10 comprising a first annular cavity 21 concentrating

  to a second cavity 22 circular in the assembly. The width of the annular cavity 21 may be between 0.1 mm and 2 mm and its depth may be between 0.05 mm and 0.15 mm. The circular cavity 22 may have a depth of between 0.05 mm and 0.3 mm and a diameter of between 2 mm and 5 mm. The radial distance between the cavities

21 and 22 can reach 1 mm.

Claims (5)

  A golf ball having a plurality of cells in its spherical outer surface, characterized in that each cell (10; 20) comprises a first cavity (11; 21) and a second cavity (13; second cavities being immediately adjacent one   with each other on a big circle of the ball.   Golf ball according to claim 1, characterized in that the first cavity (11) and the second cavity (13) have substantially the same   dimensions and the same configuration.   Golf ball according to claim 1, characterized in that the first cavity (21) has small dimensions and a small configuration by relative to the second cavity (22).   4. Golf ball according to any one of   Claims 1 to 3, characterized in that the   first cavity (21) comprises a concentric ring at the second cavity (22).   5. Golf ball according to any one of   Claims 1 to 4, characterized in that   cells (10; 20) are distributed over the spherical outer surface of the bale in a regular pattern and uniform.