U.S. patent application number 12/116973 was filed with the patent office on 2009-09-17 for vibration reducing golf club.
This patent application is currently assigned to INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE. Invention is credited to Chin-Tang Chang, Dar-Ming Chiang, Hui-Yen Chuang, Huang-Chieh Fang, Sheng-Long Liang, Shu-Ru Lin, Jaw-Min Pern.
Application Number | 20090233729 12/116973 |
Document ID | / |
Family ID | 41063660 |
Filed Date | 2009-09-17 |
United States Patent
Application |
20090233729 |
Kind Code |
A1 |
Chiang; Dar-Ming ; et
al. |
September 17, 2009 |
VIBRATION REDUCING GOLF CLUB
Abstract
A vibration reducing golf club includes a club main structure
and a plurality of piezoelectric materials. The club main structure
includes a club shaft and a ball head and can sustain the
mechanical energy resulting from the swing of the club shaft and
the collision between the ball head and a golf ball and
consequently produces vibration and bending deformation. The
piezoelectric materials are connected with conductive wires and
adhered to the club shaft. When the club shaft undergoes mechanical
deformation, the piezoelectric materials can transform the energy
of mechanical deformation into electrical energy, thereby producing
a voltage output and then feeding the voltage back to another
piezoelectric material, so as to produce a deformation against the
vibration direction of the club shaft. Thus, the vibration energy
of the club shaft can be consumed. Therefore, the vibration
reducing performance can be obtained by reducing the vibration of
the club shaft.
Inventors: |
Chiang; Dar-Ming; (Hsinchu
City, TW) ; Lin; Shu-Ru; (Taichung County, TW)
; Pern; Jaw-Min; (Hsinchu County, TW) ; Liang;
Sheng-Long; (Hsinchu County, TW) ; Chang;
Chin-Tang; (Tainan City, TW) ; Fang; Huang-Chieh;
(Kaohsiung City, TW) ; Chuang; Hui-Yen; (Kaohsiung
City, TW) |
Correspondence
Address: |
JIANQ CHYUN INTELLECTUAL PROPERTY OFFICE
7 FLOOR-1, NO. 100, ROOSEVELT ROAD, SECTION 2
TAIPEI
100
TW
|
Assignee: |
INDUSTRIAL TECHNOLOGY RESEARCH
INSTITUTE
Hsinchu
TW
ADVANCED INTERNATIONAL MULTITECH CO., LTD
Kaohsiung
TW
|
Family ID: |
41063660 |
Appl. No.: |
12/116973 |
Filed: |
May 8, 2008 |
Current U.S.
Class: |
473/289 ;
473/318 |
Current CPC
Class: |
A63B 53/00 20130101;
A63B 2220/833 20130101; A63B 60/48 20151001; A63B 24/00 20130101;
A63B 2209/00 20130101; A63B 60/08 20151001; A63B 60/10 20151001;
A63B 60/06 20151001; A63B 21/00181 20130101; A63B 2220/64 20130101;
A63B 2220/62 20130101; A63B 53/10 20130101; A63B 60/54 20151001;
A63B 60/00 20151001; A63B 60/002 20200801 |
Class at
Publication: |
473/289 ;
473/318 |
International
Class: |
A63B 53/00 20060101
A63B053/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 14, 2008 |
TW |
97109127 |
Claims
1. A vibration reducing golf club, comprising: a club main
structure, comprising a club shaft and a ball head, wherein the
club main structure is capable of sustaining a mechanical energy
resulting from a swing of the club shaft and collision between the
ball head and a golf ball, and produces bending deformation and
vibration; and a plurality of piezoelectric materials, adhered to
the club shaft, wherein when the club shaft undergoes mechanical
deformation, the piezoelectric materials transform an energy of
mechanical deformation into an electrical energy, thereby producing
a voltage output, thus consuming vibration energy of the club shaft
and obtaining a vibration reducing performance by reducing
vibration of the club shaft.
2. The vibration reducing golf club according to claim 1, wherein
the plurality of piezoelectric materials comprise connecting in
parallel.
3. The vibration reducing golf club according to claim 1, further
comprising: a control module, comprising: a conductive circuit
configuration, cross-connecting the piezoelectric materials; and a
control circuit configuration, for controlling voltage output and
transmission after one of the piezoelectric materials transforms
the mechanical energy into the electrical energy, and applying the
produced electrical energy to another piezoelectric material, so as
to transform the electrical energy into the mechanical energy; and
an energy storage module, for providing the electrical energy
required by the control module.
4. The vibration reducing golf club according to claim 3, wherein a
cross-connect manner of the conductive circuit configuration
comprises serial connection or parallel connection.
5. The vibration reducing golf club according to claim 3, wherein
the energy storage module comprises a battery or an energy storage
device.
6. The vibration reducing golf club according to claim 5, wherein
the energy storage device stores the electrical energy output by
the piezoelectric materials into a rechargeable cell.
7. The vibration reducing golf club according to claim 6, wherein
the energy storage device comprises a rectifier circuit, a
capacitor, and the rechargeable cell.
8. The vibration reducing golf club according to claim 6, wherein
the control circuit configuration comprises a vibration control
configuration, capable of releasing a voltage stored in the
rechargeable cell through a control circuit after the ball head
hits the golf ball, and leading the voltage to the piezoelectric
materials, so as to transform the electrical energy into the
mechanical energy, thereby releasing a force to resist the
deformation of the club shaft.
9. The vibration reducing golf club according to claim 8, wherein
the vibration control configuration further comprises an amplifier,
for amplifying the voltage output by one of the piezoelectric
materials, and applying the voltage to another piezoelectric
material.
10. The vibration reducing golf club according to claim 3, wherein
the control circuit configuration further comprises a power driving
circuit configuration, for releasing a force when the ball head
hits the golf ball, so as to increase a flight kinetic energy of
the golf ball.
11. The vibration reducing golf club according to claim 10, wherein
the power driving circuit configuration comprises a timer.
12. The vibration reducing golf club according to claim 11, wherein
when the piezoelectric materials are deformed to transform the
mechanical energy into the electrical energy to produce the voltage
output, the power driving circuit configuration triggers the timer
to start counting, and after a period of time, the voltage stored
in a rechargeable cell is released through a control circuit, and
is led to one of the piezoelectric materials, such that the
electrical energy is transformed into the mechanical energy, so as
to output a power to drive the club shaft, thereby enhancing an
impact force of the ball head when hitting the golf ball.
13. The vibration reducing golf club according to claim 12, wherein
the period of time when the timer is counting starts when the club
shaft begins to deform and ends when the club shaft restores and
the ball head finishes hitting the golf ball.
14. The vibration reducing golf club according to claim 3, wherein
the conductive circuit configuration further comprises a switching
switch, for switching the control circuit configuration to a
vibration control configuration or a power driving circuit
configuration.
15. The vibration reducing golf club according to claim 1, wherein
a position of the piezoelectric materials adhered to the club shaft
is one selected from a deformation region of a resonant frequency
mode of the club shaft in a vibration reducing frequency scope, so
as to obtain the vibration reducing effect.
16. The vibration reducing golf club according to claim 15, wherein
the position of the piezoelectric materials adhered to the club
shaft comprises several regions.
17. The vibration reducing golf club according to claim 1, wherein
the piezoelectric materials comprise a combination of a plurality
of units adhered to the club shaft along its axis.
18. The vibration reducing golf club according to claim 1, wherein
one of the piezoelectric materials is adhered to the club shaft
along its axis, and anther piezoelectric material is adhered to a
corresponding other side of the club shaft.
19. The vibration reducing golf club according to claim 18, wherein
polarities of the piezoelectric materials adhered to two sides of
the club shaft are arranged in same or opposite directions.
20. The vibration reducing golf club according to claim 1, wherein
the piezoelectric materials are adhered to the club shaft along its
axes at different angles.
21. The vibration reducing golf club according to claim 20, wherein
polarities of the piezoelectric materials adhered to the club shaft
along its axes at different angles are arranged in same or opposite
directions.
22. The vibration reducing golf club according to claim 1, wherein
the piezoelectric materials are adhered to the club shaft through
an outer adhesion manner.
23. The vibration reducing golf club according to claim 1, wherein
the club shaft further comprises a plurality of grooves, and the
piezoelectric materials are embedded in the grooves.
24. The vibration reducing golf club according to claim 1, wherein
the piezoelectric materials are adhered to an inner tube wall of
the club shaft through an inner adhesion manner.
25. The vibration reducing golf club according to claim 1, wherein
when the club shaft is the composite material shaft, the
piezoelectric materials are encapsulated by a lamination layer of
the composite material shaft.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the priority benefit of Taiwan
application serial no. 97109127, filed Mar. 14, 2008. The entirety
of the above-mentioned patent application is hereby incorporated by
reference herein and made a part of this specification.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention generally relates to a vibration
reducing golf club.
[0004] 2. Description of Related Art
[0005] Along with the progress of technology, material culture and
life quality are gradually improved, and sports and leisure
activities become fashionable. Golf, used to be a noble game played
by nobility, is popularized therewith. More and more people of all
age groups and different genders get involved in the golf game, and
most of them are golf lovers. Currently, the number of people
involved in the golf is increasing abruptly.
[0006] In Taiwan area, the number of manufacturers of the golf
equipments grows increasingly, and the techniques and export
amounts are progressively improved. In recent years, manufacturers
of the golf club continuously bring in new materials and new
techniques to improve the quality and accelerate the production of
the golf clubs. Among the golf clubs, the carbon fiber golf club,
made of a composite material and characterized by "light, thin,
elastic, and flexible" etc., is developed and gradually warmly
welcomed by the international market. Many manufacturers accept the
appointments from the international famous sports brand to
manufacture and supply the golf equipments, and become one of the
world's largest exporters.
[0007] In the golf game, in addition to the techniques and
stability, properties of the golf clubs are also one of the factors
determining the win or lose of a game. As the golfers pay more
attention to the feeling of golf swing, the design and fabrication
of the golf clubs increasingly become important. Therefore, the
manufacturers are trying hard to provide the golfers a better
design of the golf equipments with higher performance.
SUMMARY OF THE INVENTION
[0008] Accordingly, the present invention is directed to provide a
vibration reducing golf club, so as to achieve the effect of
controlling the vibration of the golf club.
[0009] The present invention provides a vibration reducing golf
club, which includes a club main structure and a plurality of
piezoelectric materials. The club main structure includes a club
shaft and a ball head. The club main structure can sustain the
mechanical energy resulting from the swing of the club shaft and
collision between the ball head and a golf ball and produces
bending deformation and vibration. The piezoelectric materials are
adhered to the club shaft. When the club shaft undergoes mechanical
deformation, the piezoelectric materials transform the energy of
mechanical deformation into an electrical energy, thereby producing
a voltage output. Thus, the vibration energy of the club shaft can
be consumed. Therefore, the vibration reducing performance can be
obtained by reducing the vibration of the club shaft.
[0010] The vibration reducing golf club in the present invention
further includes a control module and an energy storage module. The
control module includes a conductive circuit configuration and a
control circuit configuration. The conductive circuit configuration
cross-connects the piezoelectric materials. The control circuit
configuration is used to control the voltage output and
transmission after one of the piezoelectric materials transforms
the mechanical energy into an electrical energy, and to apply the
produced electrical energy to another piezoelectric material, so as
to transform the electrical energy into the mechanical energy. The
energy storage module is used to provide the electrical energy
required by the control module.
[0011] In the present invention, the piezoelectric materials are
adhered to the club, and produce the electromechanical coupling
effect to achieve the effect of controlling the vibration of the
golf club. Further, the energy storage device may be added to store
the piezoelectric energy transformed by the piezoelectric
materials. In addition, the present invention utilizes a converse
piezoelectric effect of the piezoelectric materials to transform
the electrical energy into the mechanical energy, so as to release
a power in forward direction of the collision, thereby enhancing
the force for hitting a golf ball. After the collision, a force in
opposite direction of the vibration of the club shaft is released
by the converse piezoelectric effect of the piezoelectric
materials, so as to resist and consume the vibration of the club
shaft, thereby achieving better vibration reducing effect.
[0012] In order to the make aforementioned and other objects,
features and advantages of the present invention comprehensible,
embodiments accompanied with figures are described in detail
below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The accompanying drawings are included to provide a further
understanding of the invention, and are incorporated in and
constitute a part of this specification. The drawings illustrate
embodiments of the invention and, together with the description,
serve to explain the principles of the invention.
[0014] FIG. 1A is a schematic structural view of a vibration
reducing golf club according to a first embodiment of the present
invention.
[0015] FIG. 1B is a partial cross-sectional view of FIG. 1A.
[0016] FIGS. 1C and 1D are schematic views showing wire connections
of the piezoelectric materials of the vibration reducing golf club
according to the first embodiment.
[0017] FIG. 2 is a curve diagram showing vibration velocity and
frequency response taken at an 80 cm position from a tip on a club
shaft of the vibration reducing golf club according to the first
embodiment.
[0018] FIG. 3 is a schematic structural view of an intelligent golf
club according to a second embodiment of the present invention.
[0019] FIG. 4 is a circuit diagram of an energy storage device of
the intelligent golf club according to the second embodiment.
[0020] FIG. 5 is a schematic view showing a feedback vibration
reducing system of the intelligent golf club according to the
second embodiment.
[0021] FIG. 6 is a schematic view showing a conductive circuit
configuration of the intelligent golf club according to the second
embodiment.
[0022] FIG. 7 is a schematic view showing manufacturing processes
of an inner adhering piezoelectric material according to the second
embodiment.
DESCRIPTION OF THE EMBODIMENTS
[0023] Reference will now be made in detail to the present
embodiments of the invention, examples of which are illustrated in
the accompanying drawings. Wherever possible, the same reference
numbers are used in the drawings and the description to refer to
the same or like parts.
[0024] FIG. 1A is a schematic structural view of a vibration
reducing golf club according to a first embodiment of the present
invention. FIG. 1B is a partial cross-sectional view of FIG.
1A.
[0025] Referring to FIGS. 1A and 1B, the vibration reducing golf
club 100 of the first embodiment includes a club main structure 102
and a plurality of piezoelectric materials 104a, 104b, 104c, and
104d. The piezoelectric materials 104a, 104b, 104c, and 104d may be
a single crystal piezoelectric material, such as quartz, lithium
niobate, and lithium tantalate; a thin film piezoelectric material,
such as zinc oxide; a polymer piezoelectric material, such as
polyvinylidene difluoride (PVDF); a ceramic piezoelectric material,
such as barium titanate and lead zirconate-titanate; and any
combinations of the above materials, and preferably the ceramic
piezoelectric material. The club main structure 102 includes a club
shaft 106 and a ball head 108. The club shaft 106 is, for example,
an iron shaft, a wood shaft, or a composite material shaft (for
example, a carbon fiber club). The club main structure 102 can
sustain the mechanical energy resulting from the swing of the club
shaft 106 and the collision between the ball head 108 and a golf
ball (not shown), and produces vibration and bending deformation.
The piezoelectric materials 104a, 104b, 104c, and 104d are
connected in parallel and adhered to the club shaft 106, and the
wire connection manner is shown in FIGS. 1C and 1D.
[0026] FIGS. 1C and 1D are schematic views showing wire connections
of the piezoelectric materials of the vibration reducing golf club
according to the first embodiment. In the figures, only the club
shaft 106 and the piezoelectric materials 104a and 104c disposed
correspondingly are shown. If the polarities of the sides of the
piezoelectric materials 104a and 104c facing the club shaft 106 are
positive and negative respectively, this arrangement direction is
referred to as forward direction (as shown in FIG. 1C). If the
polarities of the sides are both negative, this arrangement
direction is referred to as reverse direction (as shown in FIG.
1D). When swinging the golf club (equivalent to that the club shaft
106 undergoes the mechanical deformation), the piezoelectric
materials 104a and 104c function as sensors for sensing the
deformation of the club shaft 106, so as to transform the energy of
mechanical deformation into the electrical energy, thereby
producing a voltage output (i.e. the direct piezoelectric effect).
Thus, the piezoelectric materials 104a and 104c on two sides of the
club shaft are polarized. When the piezoelectric materials 104a and
104c adhered to the two sides of the club shaft 106 have the same
polarities, the polarization directions are the same. Therefore, if
the piezoelectric material 104a and another piezoelectric material
104c are cross-connected with their positive electrodes connected
and their negative electrodes connected respectively, a voltage
feedback is generated therebetween, which is equivalent to
connecting the piezoelectric materials 104a and 104c in parallel.
The piezoelectric material 104a is an actuator, the produced
voltage makes the corresponding piezoelectric material 104c to
produce the opposite deformation, thereby achieving the effect of
controlling vibration.
[0027] FIG. 2 is a curve diagram showing vibration velocity and
frequency response taken at an 80 cm position (centre of the
piezoelectric material) from a tip on a club shaft. The velocity in
the vibration velocity response diagram is in the unit of dBm/s,
and the value may be converted by the following equation:
dBv=20 log.sub.10(v)
where v is the vibration velocity at the measuring point of the
club, and dBv is the vibration velocity after being converted into
the log dimension. It is apparent from FIG. 2 that the amplitude of
the vibration of the vibration reducing golf club having the
piezoelectric materials with their wires cross-connected in
parallel is further reduced as compared with that without the wires
cross-connected in parallel.
[0028] In the first embodiment, the piezoelectric materials of the
vibration reducing golf club may also be adhered at the following
positions on the club shaft.
[0029] 1. The piezoelectric materials may be adhered at positions
in a larger deformation region of the resonant frequency mode of
the club shaft in the desired vibration reducing frequency scope,
so as obtain better vibration reducing effect. The larger
deformation region of the club shaft varies according to different
resonant frequencies. Therefore, the piezoelectric materials may be
adhered in several regions.
[0030] 2. The piezoelectric materials may also be adhered to an
outer surface of the club shaft or to an inner tube wall of the
club shaft as required.
[0031] 3. The piezoelectric materials may be a combination of
several units adhered to the club shaft along its axis as
required.
[0032] 4. The piezoelectric materials may be adhered to the club
shaft along its axes at different angles as required. The
polarities of the piezoelectric materials adhered to the club shaft
along its axes at different angles are arranged in forward
direction or reverse direction.
[0033] 5. The piezoelectric materials may be embedded in grooves of
the club shaft as required.
[0034] 6. When the club shaft is a composite material shaft, the
piezoelectric materials may be encapsulated by a lamination layer
of the composite material shaft as required.
[0035] To sum up, the position where the piezoelectric materials
are adhered may be one selected from one or any combinations of the
above positions.
[0036] FIG. 3 is a schematic structural view of a vibration
reducing golf club according to a second embodiment of the present
invention.
[0037] Referring to FIG. 3, the vibration reducing golf club 300 of
the second embodiment includes a club main structure 302, a
plurality of piezoelectric materials 304, a control module 306, and
an energy storage module 308. The materials of the piezoelectric
materials 304 may be selected similarly to the maimer discussed in
the first embodiment. The club main structure 302 includes a club
shaft 310 and a ball head 312. The club main stricture 302 can
sustain the mechanical energy resulting from the swing of the club
shaft 310 and the collision between the ball head 312 and a golf
ball (not shown), and produces bending deformation and vibration.
The selection of the club 310 can refer to that of the first
embodiment. The piezoelectric materials 304 are adhered on the club
shaft 310. When the club shaft 310 undergoes the mechanical
deformation, the piezoelectric materials 304 transform the energy
of mechanical deformation into the electrical energy, thereby
producing a voltage output (the piezoelectric materials are
referred to as the piezoelectric sensors herein). When the
piezoelectric materials 304 undergo the electrical energy load, the
piezoelectric materials 304 transforms the electrical energy
into-the mechanical deformation output (the piezoelectric materials
are referred to as the piezoelectric actuators herein). The
positions of the piezoelectric materials 304 adhered to the club
shaft 310 of the vibration reducing golf club are similar to those
discussed in the first embodiment. Further, only the connection
relation between the control module 306, the energy storage module
308 and the piezoelectric materials 304 is shown in FIG. 3, which
should not considered as indicating the practical positions of them
in the vibration reducing golf club 300. The energy storage module
308 is used to provide the electrical energy required by the
control module 306. For example, the energy storage module 306 may
be a battery or an energy storage device that stores the electrical
energy output by the piezoelectric materials 304 into a
rechargeable cell, as shown in FIG. 4.
[0038] FIG. 4 is a circuit diagram of an energy storage device of
the vibration reducing golf club according to the second
embodiment. The same reference numbers used in FIGS. 3 and 4 refer
to the same parts. Referring to FIG. 4, the energy storage device
400 includes a rectifier circuit 401, a capacitor 402, and a
rechargeable cell 403. The piezoelectric materials 304 transform
the mechanical energy into the electrical energy under the direct
piezoelectric effect, thereby producing a voltage output. The
voltage is applied across a rectifier circuit 401, for example a
bridge diode, and is rectified to a direct current, and then output
to the capacitor 402. The electrical energy may be first charged in
the capacitor 402, and finally output and stored in the
rechargeable cell 403. The capacitance of the capacitor 402 must
match the input voltage, and the rechargeable cell 403 may be
nickel-hydrogen cell, lithium cell, or any other rechargeable cell.
The energy storage device 400 may be used to store the electrical
energy transformed by the piezoelectric materials 304 during the
swing of the club into the rechargeable cell 403, and the stored
electrical energy may be used in the subsequent control and
reducing of the vibration.
[0039] FIG. 5 is a schematic view showing a feedback vibration
reducing system of the vibration reducing golf club according to
the second embodiment. In FIG. 5, the energy storage device is
omitted. Referring to FIG. 5, the control module 306 includes a
conductive circuit configuration 500 and a control circuit
configuration 501. The conductive circuit configuration 500
cross-connects the piezoelectric materials 304. The control circuit
configuration 501 is used to control the voltage output and
transmission after one of the piezoelectric materials (sensors) 304
transforms the mechanical energy into an electrical energy, and to
apply the produced electrical energy to another piezoelectric
material (actuator) 304, so as to transform the electrical energy
into the mechanical energy. In addition, the control circuit
configuration 501 may also be a vibration control configuration,
capable of releasing the voltage stored in the rechargeable cell
(403 in FIG. 4) through a control circuit (not shown) after the
ball head (312 in FIG. 3) hits the golf ball (not shown), and
leading the voltage to the piezoelectric materials (actuators) 304,
so as to transform the electrical energy into the mechanical
energy, thereby releasing a force to resist the deformation of the
club shaft 310. Also, in order to achieve a better vibration
reducing effect, the vibration control configuration may further
include an amplifier, for amplifying the voltage output by the
piezoelectric materials (sensor) 304. In addition, the control
circuit configuration 501 can also include a power driving circuit
configuration, for releasing a force when the ball head hits the
golf ball (not shown), so as to increase the flight kinetic energy
of the golf ball. For example, when the piezoelectric materials are
deformed to transform the mechanical energy into the electrical
energy to produce the voltage output, the power driving circuit
triggers the timer to start counting. After a period of time (i.e.
starting when the club shaft 310 begins to deform and ending when
the club shaft 310 restores and the ball head finishes hitting the
golf ball), the voltage stored in a rechargeable cell (403 of FIG.
4) is released through a control circuit, and is led to one of the
piezoelectric materials (actuators) 304, such that the electrical
energy is transformed into the mechanical energy, so as to output a
power to drive the club shaft 310, thereby enhancing an impact
force of the ball head 312 when hitting the golf ball.
[0040] FIG. 6 is a schematic view showing a conductive circuit
configuration of the vibration reducing golf club according to the
second embodiment. Referring to FIG. 6, if the polarities of the
sides of the piezoelectric materials 304 facing the club shaft 310
are positive and negative respectively, this arrangement direction
is referred to as forward direction. If the polarities of the sides
are both negative, this arrangement direction is referred to as
reverse direction. Therefore, the piezoelectric materials in FIG.
6(a) are connected in parallel in forward direction, the
piezoelectric materials in FIG. 6(b) are connected in series in
forward direction, the piezoelectric materials in FIG. 6(c) are
connected in parallel in opposite directions, and the piezoelectric
materials in FIG. 6(d) are connected in series in opposite
directions. Therefore, if the piezoelectric materials 304 are
connected in parallel, the produced voltage makes corresponding
piezoelectric materials to produce opposite deformation tendencies,
thereby restraining the original deformation and achieving the
vibration reducing effect. On the contrary, if two piezoelectric
materials 304 are connected in series, the potential energy of the
voltage produced by the two piezoelectric materials may be added,
thereby achieving a better energy storage effect. In addition, the
conductive circuit configuration may further include a switching
switch (not shown), for switching the control circuit configuration
(501 in FIG. 5) to the vibration control configuration or the power
driving circuit configuration.
[0041] The adhesion manner of the piezoelectric materials 304 of
the second embodiment may be an outer adhesion, inner adhesion, or
encapsulating manner. Among the manners, the outer adhesion and the
inner adhesion will not affect the original golf club manufacturing
process. In FIG. 7, the piezoelectric materials 304 are adhered,
for example, in the inner adhesion manner, which is only an example
for fabricating the piezoelectric materials of the second
embodiment and is not intended to limit the fabricating method of
the structure of the present invention.
[0042] FIG. 7 is a schematic view showing manufacturing processes
of an inner adhering piezoelectric material according to the second
embodiment. Referring to FIG. 7, the composite material of the
second embodiment may be formed by six piezoelectric strips 700
having a size of 50 mm*2 mm*0.3 mm, four conductive copper foils
702 having a size of 160 mm*1.5 mm*14 .mu.m, and two glass
fiber/epoxy resin prepreg cloths 704 having a size of 160 mm*10 mm.
The molds required by the manufacturing process are divided into an
inner mold 706 and an outer mold 708. The inner mold 706 is made of
a high molecular material, for example, PTFE, Teflon, or any other
fluoro polymer material, and has the characteristics such as fine
release and high expansion coefficients. The outer diameter of the
inner mold 706 equals to the inner tube diameter of the club shaft
minus twice the thicknesses of the piezoelectric strips 700, the
conductive copper foils 702, and the prepreg cloths 704. The outer
mold 708 is a metal mold made of an aluminium or a steel material,
and the inner diameter thereof equals to the inner tube diameter of
the club shaft.
[0043] The manufacturing processes of FIG. 7 are described as
follows.
[0044] In Step 1, one glass fiber/epoxy-resin prepreg cloth 704 is
adhered on a surface of the inner mold 706 made of the fluoro
polymer material.
[0045] In Step 2, each of the conductive copper foils 702 is
respectively adhered at the symmetrical position
(0.degree./180.degree. or 90.degree./270.degree.).
[0046] In Step 3, three piezoelectric strips 700 are placed on each
of the conductive copper foils 702.
[0047] In Step 4, the conductive copper foils 702 are respectively
placed on the piezoelectric strips 700, and an insulating material
is coated between the piezoelectric strips 700, so as to isolate
the upper and the lower conductive copper foils 702.
[0048] In Step 5, one glass fiber/epoxy resin prepreg cloth 704 is
adhered to the conductive copper foils 702.
[0049] In Step 6, they are encapsulated by one OPP thin film
encapsulates, and placed into the outer mold 708 of moulded
metal.
[0050] In Step 7, the outer mold 708 is placed into a hot press
machine, and is pressurized to 2 kg/cm.sup.2 and heated for 30
minutes in an environment of 135.degree. C.
[0051] In Step 8, the outer mold 708 is cooled down, then opened,
so as to remove the OPP thin film and take out the inner mold 706,
thus obtaining the moulded piezoelectric unit.
[0052] In Step 9, a solvent type epoxy adhesive curable at
130.degree. C. is coated on the surface of the piezoelectric unit,
and then the piezoelectric unit is laid for the solvent evaporating
to dry.
[0053] In Step 10, the piezoelectric unit is pushed into the
appropriate position in the club shaft by a fixture.
[0054] In Step 11, the club is placed into the oven and heated at
135.degree. C. for 30 minutes, thus finishing the assembly
processes of the inner adhering piezoelectric materials.
[0055] To sum up, the present invention uses the piezoelectric
materials to transform the mechanical load into the voltage output,
or transform the voltage input into the force output, and thus
having the advantages of high piezoelectric constant, quick
response, small volume, and no electromagnetic interference, etc.
Therefore, when applied to the golf club, the present invention
alleviates the vibration resulting from the collision between the
golf club and the golf ball, and particularly, the violent
vibration caused by failing to hit the sweet spot. In addition, the
present invention also employs the control module and the energy
storage module to control the piezoelectric materials, so as to
achieve a vibration reducing golf club capable of reducing the
vibration and/or enhancing the hitting force.
[0056] It will be apparent to those skilled in the art that various
modifications and variations can be made to the structure of the
present invention without departing from the scope or spirit of the
invention. In view of the foregoing, it is intended that the
present invention cover modifications and variations of this
invention provided they fall within the scope of the following
claims and their equivalents.
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