U.S. patent application number 15/185620 was filed with the patent office on 2017-01-05 for golf ball with built-in ic chip.
This patent application is currently assigned to Bridgestone Sports Co., Ltd.. The applicant listed for this patent is Bridgestone Sports Co., Ltd.. Invention is credited to Atsushi KOMATSU.
Application Number | 20170001080 15/185620 |
Document ID | / |
Family ID | 57683579 |
Filed Date | 2017-01-05 |
United States Patent
Application |
20170001080 |
Kind Code |
A1 |
KOMATSU; Atsushi |
January 5, 2017 |
GOLF BALL WITH BUILT-IN IC CHIP
Abstract
A golf ball of the present invention includes a small-size IC
tag including an IC chip and a first antenna directly connected to
the IC chip and having a size of 5 mm or less; and a conductive
second antenna of which a part is disposed near the IC tag. The IC
tag and the second antenna do not need to be in physical contact
with each other. The distance between the part of the second
antenna and the IC tag may be at most 1 mm. The second antenna may
be arranged over at least a half of the circumference of the golf
ball.
Inventors: |
KOMATSU; Atsushi;
(Chichibu-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Bridgestone Sports Co., Ltd. |
Tokyo |
|
JP |
|
|
Assignee: |
Bridgestone Sports Co.,
Ltd.
Tokyo
JP
|
Family ID: |
57683579 |
Appl. No.: |
15/185620 |
Filed: |
June 17, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A63B 2225/50 20130101;
A63B 37/0076 20130101; A63B 37/0075 20130101; A63B 37/0074
20130101; A63B 37/007 20130101; A63B 69/3688 20130101; A63B 43/004
20130101 |
International
Class: |
A63B 43/00 20060101
A63B043/00; A63B 37/00 20060101 A63B037/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 30, 2015 |
JP |
2015-131623 |
Claims
1. A golf ball with a built-in integrated circuit (IC) chip,
comprising: a core located in a center of the golf ball; a cover
surrounding an outside of the core; an IC tag arranged between the
core and the cover, the IC tag comprising an IC chip and a first
antenna directly connected to the IC chip; and a second antenna of
which a part is disposed near the IC tag.
2. The golf ball according to claim 1, wherein the IC tag and the
second antenna are not in physical contact with each other.
3. The golf ball according to claim 1, wherein the part of the
second antenna disposed near the IC tag is located within 1 mm from
the IC tag.
4. The golf ball according to claim 2, wherein the part of the
second antenna disposed near the IC tag is located within 1 mm from
the IC tag.
5. The golf ball according to claim 1, wherein the second antenna
is disposed over at least a half of an outer periphery of the IC
tag.
6. The golf ball according to claim 1, wherein the second antenna
is arranged over at least a half of a circumference of the golf
ball.
7. The golf ball according to claim 2, wherein the second antenna
is disposed over at least a half of an outer periphery of the IC
tag and is arranged over at least a half of a circumference of the
golf ball.
8. The golf ball according to claim 1, wherein the IC chip has a
size of at most 5 mm.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This Application claims priority from Japanese Patent
Application No. 2015-131623 filed Jun. 30, 2015, which is
incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a golf ball with a built-in
integrated circuit (IC) chip such as a radio-frequency
identification (RFID) chip.
[0003] In order to record information about golf balls, such as the
material, the location of production, and the production date in
the golf balls, attempts have been made to incorporate an IC chip
in golf balls.
[0004] For example, JP 2013-154176 A discloses that an RFID circuit
and an antenna connected thereto are formed on the surface of the
cover of a golf ball by using a conductive ink in order to prevent
damage to the built-in IC chip that may occur when the golf ball is
hit.
SUMMARY OF THE INVENTION
[0005] To transmit and receive information by wireless
communication, a metal antenna is usually connected to a silicon IC
chip. Small IC tags with an IC chip including a built-in antenna
are currently being sold; however, because the antenna of such an
IC tag is short, the communication range may be short when it is
incorporated in golf balls, and as a result, the IC tag cannot be
easily read by a reader. Accordingly, in incorporating such an IC
tag in a golf ball, it is necessary to connect a long antenna to
the IC chip. However, because a golf ball is greatly deformed at
the moment it is hit, a problem may arise in that the bonding
portion between the IC chip and the antenna is particularly easily
damaged, and thus, communication may very soon fail.
[0006] In order to solve the above-described problem, an object of
the present invention is to provide a golf ball with a built-in IC
chip capable of preventing communication failure that may occur due
to damage on the IC chip incorporated in the golf ball caused by
impact from hitting of the ball.
[0007] In order to achieve the above-described object, a golf ball
with a built-in IC chip according to the present invention
includes: a core located in the center of the golf ball; a cover
surrounding an outside of the core; an IC tag arranged between the
core and the cover, the IC tag further including an IC chip and a
first antenna directly connected to the IC chip; and a second
antenna of which a part is disposed near the IC tag.
[0008] It is not necessary for the second antenna and the IC tag to
be in physical contact with each other. Preferably, the part of the
second antenna disposed near the IC tag may be located within a
distance of at most 1 mm from the IC tag. The second antenna may be
disposed over at least a half of the outer periphery of the IC tag.
The second antenna may be arranged over at least a half of the
circumference of the golf ball. The size of the IC chip may be at
most 5 mm.
[0009] As described above, according to the present invention, a
part of the second antenna being disposed near the IC tag which
includes the built-in first antenna and is arranged between the
core and the cover of the golf ball, and thus, the second antenna
functions as an antenna for the IC chip via the first antenna in
the IC tag although the second antenna is not physically connected
with the IC chip in the IC tag for electrical connection.
Accordingly, the communication distance of the IC tag can be
dramatically extended compared with the case of using the IC tag
only. In addition, the second antenna is physically coupled with
neither the IC chip nor the first antenna, and thus, there is no
case in which a bonding portion between the second antenna and the
IC chip is damaged due to the hitting of the golf ball, resulting
in preventing communication failure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a plan view schematically showing an embodiment of
a golf ball according to the present invention.
[0011] FIG. 2 is a perspective view schematically showing an RFID
tag incorporated in the golf ball illustrated in FIG. 1.
[0012] FIG. 3 is a schematic cross sectional view of the golf ball
illustrated in FIG. 1 along a line III-III.
[0013] FIG. 4 is a schematic cross sectional view showing another
embodiment of a golf ball according to the present invention.
[0014] FIG. 5 is a perspective view showing an IC chip with an
external antenna used in a Comparative Example.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] Hereinafter, embodiments of a golf ball with a built-in IC
chip according to the present invention will be described with
reference to the accompanying drawings. The embodiments will be
described merely for easier understanding of the present invention,
and the present invention is not limited thereto. Also, the
components in the drawings are not necessarily to scale, emphasis
instead being placed upon clearly illustrating the principles of
the present invention.
[0016] As shown in FIG. 1, a golf ball 1 of the present embodiment
includes a core 10 arranged in the center of the golf ball; a cover
20 surrounding an outer periphery of the core; an RFID tag 30 for
transmitting and receiving information by wireless communication;
and a boost antenna 40 for the RFID tag as main components. A
plurality of dimples (not shown) is formed on the surface of the
cover 20.
[0017] As shown in FIG. 2, the RFID tag 30 includes an IC chip 32
for storage and computation of the information; and a built-in
antenna 36 for exchanging wireless frequency signals. The IC chip
32 and the built-in antenna 36 are directly and physically
connected with each other for electrical connection. Specifically,
the terms "RFID tag" and "IC tag" herein refers to a tag including
an IC chip and an antenna which is directly connected to the IC
chip are integrally implemented, and the antenna will be hereafter
referred to as the "built-in antenna" or the "first antenna".
[0018] In the present embodiment, the RFID tag 30 includes the IC
chip 32 and the built-in antenna 36 integrally formed on a
substrate 34 as illustrated in FIG. 2. However, the present
invention is not limited to this configuration. Specifically, the
RFID tag 30 may alternatively include an IC chip and a built-in
antenna directly connected to the IC chip, which are integrated
together by using a sealing material, for example. The shape of the
RFID tag is not limited to a flat rectangular solid as illustrated
in the drawing, and it may have a disc-like shape.
[0019] To prevent dislocation of the center of gravity point of the
golf ball from the center of the ball, the smaller the size of the
RFID tag 30, the more preferable it is. Specifically, the size of
the RFID tag 30 is preferably 5 mm or less, and more preferably 3
mm or less. If the flat rectangular solid shape is employed, the
length and the width are preferably 5 mm or less, more preferably 3
mm or less, respectively, for example. If the disc-like shape is
employed, the diameter is preferably 5 mm or less, more preferably
3 mm or less, for example. For both the configuration which employs
the flat rectangular solid shape and the configuration which
employs the disc-like shape, the thickness of the RFID tag 30 is
preferably 1 mm or less, and more preferably 0.5 mm or less.
[0020] The IC chip 32 may be a passive chip which operates by radio
waves received from an external reader (not shown). However, the IC
chip 32 may also be an active chip incorporating a battery cell. In
this configuration, the built-in battery cell can be charged by
using a contactless charger.
[0021] The IC chip 32 is not particularly limited in terms of the
frequency band to be used. Specifically, the IC chip 32 may use the
13.56 MHz band (high frequency (HF) band) or the 952 to 954 MHz
bands (ultrahigh frequency (UHF) bands), for example.
[0022] The boost antenna 40 is disposed near the RFID tag 30,
particularly in a center portion 40a thereof. The term "disposed
near" herein refers to a state in which the boost antenna 40 is
disposed near, close to, proximately to, in the vicinity of, or
around the RFID tag 30, including a state in which the boost
antenna 40 and the RFID tag 30 are not in physical contact for
electrical connection, but the boost antenna 40 and the RFID tag 30
may be in non-electrical contact. Preferably, the RFID tag and the
boost antenna 40 are arranged so that the distance therebetween is
at most 1 mm.
[0023] By arranging the boost antenna 40 in relation to the RFID
tag 30 in the above-described manner, even if a strong impact has
been applied to the golf ball 1 due to hitting with a golf club,
communication failure that may occur in the conventional technique
due to damage on the connection portion between the IC chip and the
antenna can be prevented because the IC chip 32 of the RFID tag 30
and the boost antenna 40 are not physically connected for
electrical connection.
[0024] The boost antenna 40 is preferably arranged so that the
above-described part thereof is disposed over at least a half of
the outer periphery of the RFID tag 30 as illustrated in FIG. 1. Of
course, in an alternative configuration, the boost antenna 40 may
be arranged so that a part thereof is disposed on the entire outer
periphery of the RFID tag 30.
[0025] The material of the boost antenna 40 is not particularly
limited, except that it is a conductive material, and a metal yarn
and a conductive yarn can be used. Examples of the metal yarn that
can be used include filaments such as gold filament, silver
filament, copper filament, and aluminum filament, and strands or
knits of such filaments. For the conductive yarn, yarns including a
core constituted by fibers such as nylon fiber and polyester fiber
plated with metals such as silver and copper can be used. The
percentage content of the metal constituting the conductive yarn is
not particularly limited except that the content is high enough to
secure the conductivity. Specifically, for example, the percentage
content of the metal is preferably in a range of 10 to 70% by
weight. In addition, in order to securely position the center of
gravity point of the golf ball 1 in the center of the ball, it is
preferable for the composition of the metal yarn and the conductive
yarn to be a composition with which the specific gravity of the
boost antenna 40 becomes the same as the specific gravity of the
layer in which the RFID tag 30 and the like are arranged.
[0026] The diameter of the boost antenna 40 (the metallic yarn and
the conductive yarn) is not particularly limited, and an upper
limit thereof is preferably 1.5 mm or less, more preferably 1.0 mm.
A lower limit thereof is preferably 0.1 mm or more, more preferably
0.3 mm or more.
[0027] The RFID tag 30 and the boost antenna 40 are arranged
between the core 10 and the cover 20 as illustrated in FIG. 3. In
the golf ball 1 with the two-piece structure constituted by the
core 10 and the cover 20, it is preferable to embed the RFID tag 30
into a groove 12 formed on the surface of the core 10. In this
configuration, it is preferable that the surface of the RFID tag 30
be flush with the surface of the core 10.
[0028] It is preferable to arrange the boost antenna 40 so that
both side portions 40b, 40c extending from the center portion 40a
disposed near the RFID tag 30 extend in mutually opposite
directions along the surface of the core 10. It is preferable that
both side portions 40b, 40c have the same length. For the length of
the entire boost antenna 40, the boost antenna 40 is arranged over
about 3/4 of the circumference of the golf ball 1 or the core 10 in
FIG. 3. However, the present invention is not limited to this.
Specifically, it is preferable to arrange the boost antenna 40 on a
portion that corresponds to at least a half of the circumference of
the golf ball 1 or the core 10. With the above-described
configuration, the communication range is extended, and
communication with the RFID tag 30 can be performed by using a
reader at any location on the golf ball 1, i.e., even at a location
on the golf ball on the opposite side of the RFID tag 30.
[0029] The shape or the arrangement of both side portions 40b, 40c
of the boost antenna are not limited to those described above.
Specifically, for example, both side portions 40b, 40c may extend
over the entire circumference of the golf ball, may extend either
in a straight shape or a curved shape, or alternatively,
considering the symmetry of the golf ball, the boost antenna may be
branched from the center portion into four parts to form an X-like
shape.
[0030] The present invention can be employed in a golf ball having
a multi-piece structure. For example, in a configuration in which
the golf ball includes an intermediate layer 50 arranged between
the core 10 and the cover 20 as illustrated in FIG. 4, it is
preferable to embed the RFID tag 30 in a groove 52 formed on the
surface of the intermediate layer 50. In addition, it is preferable
to arrange the boost antenna 40 antenna 40 so that the both side
portions 40b, 40c extending from the center portion 40a disposed
near the RFID tag 30 extend in mutually opposite directions along
the surface of the intermediate layer 50. The number of the
intermediate layer 50 is not limited to one as illustrated in FIG.
4, and alternatively, a plurality of intermediate layer 50 may be
arranged. In the golf ball having the multi-piece structure, if a
plurality of intermediate layers is provided, it is preferable to
arrange the RFID tag and the boost antenna on the surface of the
layer located in an inside of the layer in the outermost shell
(i.e., the cover), and thereby a sufficient communication distance
can be secured. In terms of the diameter of the golf ball, the
boost antenna 40 is arranged on an imaginary sphere having a
diameter of preferably 42 mm or less, more preferably 40 mm or less
and having the same center as the golf ball. Also, the boost
antenna 40 is arranged on a sphere having a diameter of preferably
20 mm or more, more preferably 30 mm or more.
[0031] The core 10 can be formed primarily from rubber. For the
rubber (base material rubber) used as the main component, a wide
variety of rubbers can be used. Examples of such a rubber include,
but are not limited to, polybutadiene rubber (BR),
styrene-butadiene rubber (SBR), natural rubber (NR), polyisoprene
rubber (IR), polyurethane rubber (PU), and silicone rubber.
[0032] In addition to the base material rubber that is the main
component, optional components such as co-crosslinking agent,
crosslinking agent, filler, age resistor, isomerization agent,
peptizer, sulfur, and organosulfur compound can be added to the
core 10. As the main component, a resin may be used instead of the
rubber. Specifically, a thermoplastic elastomer, an ionomer resin,
or a mixture thereof can also be used, for example.
[0033] The hardness of the core 10 is not particularly limited, and
an upper limit thereof is preferably 60 or less, more preferably 50
or less, yet more preferably 40 or less, by the Shore D hardness. A
lower limit of the hardness of the core 10 is preferably 20 or
more, more preferably 30 or more, by the Shore D hardness.
[0034] The core 10 has a substantially spherical shape. An outer
diameter of the core 10 is preferably 42 mm or less, more
preferably 41 mm or less, yet more preferably 40 mm or less.
Considering that the repulsion of the golf ball may be lowered if
the outer diameter of the core 10 is too small, a lower limit of
the outer diameter of the core 10 is preferably 5 mm or more, more
preferably 15 mm or more, yet more preferably 25 mm or more. The
core 10 is a solid core as illustrated in FIG. 3. However, the core
10 is not limited to this, and a hollow core may be used. In
addition, the core 10 includes one layer as illustrated in FIG. 3.
However, the core 10 is not limited to this and may be constituted
by a plurality of layers including a center core and one or more
surrounding layers.
[0035] The cover 20 can be formed by using a material that uses,
but is not limited to, an ionomer resin, a polyurethane
thermoplastic elastomer, thermosetting polyurethane, and a mixture
thereof as the main component. For the above-described main
component, a two-component curing type polyurethane resin can also
be used. Further, in addition to the main component described
above, other thermoplastic elastomers, a polyisocyanate compound,
fatty acid or a derivative thereof, a basic inorganic metal
compound, a filler, and the like can be added to the cover 20.
[0036] For the ionomer resin, a resin including, but not limited
to, the following (a) component and/or (b) component as the base
resin can be used. In addition, the following (c) component can be
added to the base resin. The (a) component is an olefin-unsaturated
carboxylic acid-unsaturated carboxylic ester ternary random
copolymer and/or a metal salt thereof, the (b) component is an
olefin-unsaturated carboxylic acid binary random copolymer and/or a
metal salt thereof, and the (c) component is a thermoplastic block
copolymer including a polyolefin crystalline block and a
polyethylene/butylene random copolymer.
[0037] The hardness of the material constituting the cover 20 is
not particularly limited, and a lower limit thereof is preferably
50 or more, more preferably 55 or more, by the Shore D hardness. An
upper limit thereof is preferably 75 or less, more preferably 70 or
less, yet more preferably 65 or less, by the Shore D hardness.
[0038] A lower limit of the thickness of the cover 20 is, but is
not limited to, preferably 0.2 mm or more, more preferably 0.4 mm
or more. An upper limit of the thickness of the cover 20 is, but is
not limited to, preferably 4 mm or less, more preferably 3 mm or
less, yet more preferably 2 mm or less. A plurality of dimples (not
illustrated) is formed on the surface of the cover 20. The size,
the shape, the number, and the like can be appropriately designed
according to the aerodynamic performance desired for the golf
ball.
[0039] For the material of the intermediate layer 50, an
intermediate layer having a core-like function may be formed by
using the same material as that of the core described above, and
alternatively, an intermediate layer having a cover-like function
may be formed by using the same material as that of the cover
described above. In a configuration including a plurality of
intermediate layers, a first intermediate layer having a core-like
function and a second intermediate layer having a cover-like
function, for example, may be provided.
[0040] It is preferable that the golf ball constituted by the core
10, the cover 20, and the optional intermediate layer 50 described
above have a predetermined ball hardness. The ball hardness refers
to a deformation amount of the golf ball when loads from the
initial load of 98 N to the final load of 1275 N are applied to the
golf ball (i.e., an amount of compressive deformation). The unit is
expressed in "mm". The rate of compression is 10 mm/s. For this
ball hardness (deformation amount), the smaller the numerical value
thereof, the harder the golf ball, and the higher the numerical
value thereof, the softer the golf ball. In addition, the
deformation amount affects the hitting feeling felt by the golfer
when the golfer takes a shot, the durability, and the like.
Accordingly, it is preferable that a lower limit of the deformation
amount be 1.5 mm or more and an upper limit thereof be 5.0 mm or
less.
[0041] Next, an embodiment of a method of producing the golf ball 1
incorporating the RFID tag 30 and the boost antenna 40 described
above will be described.
[0042] First, the core 10 is molded by a known method for molding a
core of a golf ball. Specifically, the core 10 can be obtained by a
method in which a material including a base material rubber is
kneaded by using a kneader, and then the kneaded material is molded
by pressurized vulcanization in round molds. The groove 12 for the
RFID tag formed on the surface of the core 10 can be formed by
using the round molds or by excavating the surface of the molded
product molded in molds by using excavation tools. The RFID tag 30
incorporating a commercial antenna, for example, is arranged in the
groove 12.
[0043] As the boost antenna 40, a metal yarn or a conductive yarn
is arranged on the surface of the core 10. In arranging them, the
boost antenna 40 is arranged so that the boost antenna 40 surrounds
the outer periphery of the RFID tag 30 over at least the half of
the outer periphery. It is desirable that the distance between the
boost antenna 40 and the RFID tag 30 be 1 mm or less. Of course,
the boost antenna 40 and the RFID tag 30 may be partially in
contact with each other.
[0044] Next, the cover 20 is formed by an injection molding method,
for example. Specifically, the core 10 in which the RFID tag 30 and
the boost antenna 40 have been arranged is placed into the mold for
the cover in the center of the mold, then the material of the cover
is introduced into the mold by injection so that the material
covers the core 10, and thereby the cover 20 can be formed. In the
above-described manner, the golf ball incorporating the RFID tag
and the boost antenna can be produced.
[0045] Note that if an active RFID tag incorporating a battery cell
is used, it is preferable that the cover be formed by introducing a
two-component curing type polyurethane resin into the mold for the
cover instead of using an injection molding method. Failure of the
battery cell incorporated in the RFID tag due to heat can be
prevented by using the two-component curing type polyurethane
resin.
[0046] A method of producing the golf ball having the multi-piece
structure including the intermediate layer 50 will be described. If
the intermediate layer is formed by the material of the core, a
known molding method for molding a multi-layer structured solid
core can be employed in molding the intermediate layer. For
example, the core 10 is obtained by the above-described method, the
obtained core is used as the center core, further, the material of
the core is kneaded by using a kneader, the kneaded material is
molded into a sheet-like shape, then the center core is covered
with the sheet and the resulting material is molded by pressurized
vulcanization in round molds, and thereby a product including the
intermediate layer 50 constituted by the material of the core and
formed around the outer periphery of the center core 10 can be
obtained. The groove 52 for the RFID tag on the surface of the
intermediate layer 50 can be formed by using the above-described
round molds or by excavating the surface of the molded product
molded in molds by using excavation tools. The RFID tag 30 is
arranged in the groove 52 and the boost antenna 40 is arranged on
the surface of the intermediate layer 50. The cover 20 is formed by
an injection molding method and the like, and thereby the golf ball
having the multi-piece structure incorporating the RFID tag and the
boost antenna can be produced.
Example
[0047] Three golf balls having the configurations shown in Table 1
were prepared for the Example of the present invention and the
Comparative Example, and tests were carried out for measuring the
durability of the golf balls and the performance of reading the
built-in RFID tag. For the RFID tags, Monza 5 (frequency band: UHF)
of Hitachi Chemical Co., Ltd. was used. All of the RFID tags were a
flat square body with the dimensions shown in Table 1. For the
boost antenna, a conductive yarn (diameter: 0.7 mm) composed of 83%
nylon and 17% silver was used. The boost antenna was disposed near
the RFID tag with the center of the RFID tag surrounding the RFID
tag on three edges of the RFID tag, within the distance from the
RFID tag of 1 mm or less. The boost antenna was arranged by 39.3 mm
on the diameter of the golf ball and along the half of the
circumference of the golf ball (core).
[0048] Note that RFID tags similar to those in the Examples were
used in the Comparative Examples including a configuration in which
no boost antenna was arranged (Comparative Example 1), a
configuration in which neither the RFID tag nor the boost antenna
was arranged (Comparative Example 2), and a configuration in which
an external antenna-bonded IC chip 60 to which an external antenna
66 (material: copper) formed with a ring-like shape and having the
outer diameter of 11 mm was bonded to a commercial IC chip 62
including no built-in antenna by using a connection material
constituted by the same material as that of the external antenna,
instead of using an RFID tag (Comparative Example 3) as illustrated
in FIG. 5. Tests similar to those for the Examples were carried out
for the Comparative Examples. The material and the composition of
the core and the cover of the golf balls were the same among
Examples 1 to 3 and Comparative Examples 1 to 3. Rubber was used as
the material of the core, and an ionomer resin was used as the
material of the cover. The hardness of the cover was D56.
TABLE-US-00001 TABLE 1 Example Comparative Example 1 2 3 1 2 3 RFID
Product Monza 5 Monza 5 Monza 5 Monza 5 -- IC chip tag name Size
1.2 .times. 1.2 .times. 0.7 1.7 .times. 1.7 .times. 0.7 2.5 .times.
2.5 .times. 0.3 1.7 .times. 1.7 .times. 0.7 -- (mm) Boost antenna
Disposed Disposed Disposed -- -- -- near/half of near/half of
near/half of circumference circumference circumference Ball outer
42.69 42.70 42.69 42.69 42.69 42.70 diameter (mm) Ball weight (g)
45.07 45.12 45.10 45.08 45.13 45.10 Ball hardness 3.21 3.25 3.22
3.23 3.19 3.20 (mm) Ball initial 77.28 77.27 77.27 77.32 77.26
77.21 velocity (m/s) Communication 20 100 300 5 -- 10 distance (mm)
COR durability 232 224 215 226 221 10
[0049] In Table 1, for all of the ball outer diameter, the ball
weight, the ball hardness, and the ball initial velocity, an
average value of the values obtained for all the three golf balls
was used. The ball initial velocity was measured by the measurement
method provided in the golf ball initial velocity rules by using an
initial velocity measurement device of the same type as the drum
rotation type initial velocity meter used by the United States Golf
Association (USGA).
[0050] For the communications distance in Table 1, AT-880 of ATID
CO., LTD. was used as an RFID reader, and the distance from the
golf ball by which the RFID tags were normally read, i.e., the
distance from the golf ball to the RFID reader, was measured.
[0051] For the COR durability in Table 1, the durability of the
golf balls was evaluated by using ADC Ball COR Durability Tester of
Automated Design Corporation (U.S.). The tester has a function for
ejecting golf balls by air pressure and colliding them
consecutively on two parallel installed metal plates. The velocity
of incidence to the metal plates was 43 m/s. An average value of
the number of times of ejections of the ball given until the ball
was broken was used as the COR durability. In these test results,
the average value refers to a value obtained by averaging the
number of times of ejections given until all three balls ejected
for each Example and each Comparative Example were broken.
[0052] The RFID reading performance was examined, and as a result,
the RFID was normally read for all the golf balls of Examples 1 to
3 and Comparative Example 1 until the balls were broken in the COR
durability test. In contrast, in Comparative Example 3 in which an
IC chip including no built-in antenna to which an external antenna
was physically bonded, the RFID was not read in the 10th ejection
of the balls, i.e., far earlier than the balls were to be broken in
the COR durability test. As a result, it was shown that by
providing the boost antenna disposed near the RFID tag
incorporating an antenna, failure of communication with the RFID
tag could be prevented even if the golf ball was hit hard. The
durability of the golf balls per se incorporating the RFID tag and
the boost antenna in their inside (Examples 1 to 3) were the same
as those of common golf balls including neither the RFID tag nor
the boost antenna (Comparative Example 2).
* * * * *