Golf ball

• US 4,840,381 A
• Filed: 06/10/1988
• Issued: 06/20/1989
• Est. Priority Date: 03/20/1986
• Status: Expired due to Term

• Current Assignee: Bridgestone Corporation
• Original Assignee: Bridgestone Corporation
• Inventors: Alaki, Yasuhide, Ihara, Keisuke, Nomura, Jun
• Primary Examiner(s): Marlo, George J.
• Application Number:
  US07/204,899
• Time in Patent Office: 375 Days
• Field of Search: 273/232, 273/227, 273/220, 273/218, 273/235 R, 273/214, 273/215, 273/216, 273/222-226, 273/228, 273/229, 273/221
• US Class Current: 473/365
• CPC Class Codes: A63B 37/0004 Surface depressions or protrusions
• CPC Class Codes: A63B 37/0006 Arrangement or layout of dimples
• CPC Class Codes: A63B 37/0012 Dimple profile, i.e. cross-sectional view
• CPC Class Codes: A63B 37/0016 Specified individual dimple volume
• CPC Class Codes: A63B 37/0017 Specified total dimple volume
• CPC Class Codes: A63B 37/0018 Specified number of dimples
• CPC Class Codes: A63B 37/0019 Specified dimple depth
• CPC Class Codes: A63B 37/002 Specified dimple diameter
• CPC Class Codes: A63B 37/0031 Hardness
• CPC Class Codes: A63B 37/0033 Thickness
• CPC Class Codes: A63B 37/0053 Thread wound
• CPC Class Codes: A63B 37/0074 Two piece balls, i.e. cover and core
• CPC Class Codes: A63B 37/008 Diameter
• CPC Class Codes: A63B 37/0083 Weight; Mass

Abstract

A golf ball having a plurality of recessed dimples in the surface thereof, wherein at least 90% in number of the dimples have a value of Vo in the range defined by the following equation:

0.35≦Vo≦0.47

wherein Vo is the volume of each dimple confined below a plane defined by the dimple edge divided by the volume of a cylinder whose bottom is defined by said plane and whose height is defined by the maximum dimple depth from the bottom: and the total volume ration Vr of the dimples is defined by the following equation:

Vr=Vs / (4πR.sup.3 /3)×100

wherein Vs is the sum of the dimple volumes as defined above, and R is the radius of the ball in the range defined by the following equation:

V.sub.RL -N/1500≦Vr≦V.sub.RU -N/1500

wherein V_RL and V_RU are defined below, and N is the number of the dimples and ranges from 400 to 600 both inclusive;

Large sized two-piece ball: V_RL =1.14, V_RU =1.22, and

Large sized thread-wound ball: V_RL =1.18, V_RU =1.26.

Claims

1. A golf ball having a plurality of recessed dimples on the surface thereof, wherein the golf ball is a large sized two-piece ball consisting of a core and a cover;

the maximum diameter of the dimples is 2 to 4 mm;

the maximum depth of the dimples is 0.1 to 0.4 mm;

the number of dimples is 400 to 600;

at least 90% of the dimples have a value of Vo in the range defined by the following equation;

space="preserve" listing-type="equation">0.35≦

Vo≦

0.47

wherein Vo is the volume of each dimple confined below a plane defined by the dimple edge divided by the volume of a cylinder whose bottom is defined by said plane and whose height is defined by the maximum dimple depth from the bottom; and

the total volume ratio Vr of the dimples is defined by the following equation;

space="preserve" listing-type="equation">Vr=Vs/(4π

R.sup.3 /3)×

100

wherein Vs is the sum of the dimple volumes as defined above, and R is the radius of the ball in the range defined by the following equation;

space="preserve" listing-type="equation">V.sub.RL -N/1500≦

Vr≦

V.sub.RU -N/1500

wherein V_RL is not less than 1.14 inclusive, V_RU is not more than 1.22 inclusive, and N is the number of the dimples and ranges from 400 to 600 both inclusive.

2. The golf ball of claim 1, wherein said cover comprises an ionomeric resin having a Shore D hardness of at least 60.

3. A golf ball having a plurality of recessed dimples on the surface thereof, wherein the golf ball is a large sized thread-wound ball consisting of a center, rubber thread and a cover;

the maximum diameter of the dimples is 2 to 4 mm;

the maximum depth of the dimples is 0.1 to 0.4 mm;

the number of dimples is 400 to 600;

at least 90% of the dimples have a value of Vo in the range defined by the following equation;

space="preserve" listing-type="equation">0.35≦

Vo≦

0.47

wherein Vo is the volume of each dimple confined below a plane defined by the dimple edge divided by the volume of a cylinder whose bottom is defined by said plane and whose height is defined by the maximum dimple depth from the bottom; and

the total volume ratio Vr of the dimples is defined by the following equation;

space="preserve" listing-type="equation">Vr=Vs/(4π

R.sup.3 /3)×

100

wherein Vs is the sum of the dimple volumes as defined above, and R is the radius of the ball in the range defined by the following equation;

space="preserve" listing-type="equation">V.sub.RL -N/1500≦

Vr ≦

V.sub.RU -N/1500

wherein V_RL is not less than 1.18 inclusive, V_RU is not more than 1.26 inclusive, and N is the number of the dimples and ranges from 400 to 600 both inclusive.

4. The golf ball of claim 3, wherein said cover comprises an ionomeric resin having a Shore D hardness of at least 60.