U.S. patent application number 14/408162 was filed with the patent office on 2015-11-05 for kendama.
The applicant listed for this patent is IWATA CO., LTD.. Invention is credited to Kazuma Iwata.
Application Number | 20150314181 14/408162 |
Document ID | / |
Family ID | 51227174 |
Filed Date | 2015-11-05 |
United States Patent
Application |
20150314181 |
Kind Code |
A1 |
Iwata; Kazuma |
November 5, 2015 |
Kendama
Abstract
This disclosure provides a kendama not only replacing only a
kensaki if the kensaki is worn, but also adjusting a balance of
weight and others of a sword and developing a novel technique
largely different from existing techniques. A kendama includes a
sword having a sword shaft and a cross-piece; a ball having a hole
of inserting a kensaki protruding to an upper side than the
cross-piece in the sword shaft; and a string connecting the sword
and the ball. A tip portion of the kensaki is configured as an
attachable and detachable member which is attachable and detachable
with respect detachable members replaced each other.
Inventors: |
Iwata; Kazuma;
(Hatsukaichi-shi, Hiroshima, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
IWATA CO., LTD. |
Hatsukaichi-shi, Hiroshima |
|
JP |
|
|
Family ID: |
51227174 |
Appl. No.: |
14/408162 |
Filed: |
September 10, 2013 |
PCT Filed: |
September 10, 2013 |
PCT NO: |
PCT/JP2013/074311 |
371 Date: |
December 15, 2014 |
Current U.S.
Class: |
473/506 |
Current CPC
Class: |
A63B 67/205 20130101;
A63B 2071/0694 20130101; A63B 59/30 20151001; A63B 67/22 20130101;
A63B 2220/806 20130101; A63B 67/10 20130101 |
International
Class: |
A63B 67/20 20060101
A63B067/20 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 28, 2013 |
JP |
2013-013533 |
Claims
1. A kendama comprising: a sword having a sword shaft and a
cross-piece; a ball having a hole of inserting a kensaki protruding
to an upper side than the cross-piece in the sword shaft; and a
string connecting the sword and the ball, wherein a tip portion of
the kensaki is configured as an attachable and detachable member
which is attachable and detachable with respect to a base end of
the kensaki, the attachable and detachable member is a plurality of
attachable and detachable members replaced each other.
2. The kendama according to claim 1, wherein at least two
attachable and detachable members out of the plurality of
attachable and detachable members differ in at least any one item
or more items out of a weight, shape, and color.
3. The kendama according to claim 1, wherein at least one
attachable and detachable member is of configuring a shape of the
tip portion of the kensaki as a hemisphere or circular cone.
4. The kendama according to claim 1, wherein at least one
attachable and detachable member is of configuring a shape of the
tip portion of the kensaki as a circular truncated cone.
5. The kendama according to claim 1, wherein at least one
attachable and detachable member is of providing a slit groove
catching the string with the tip portion of the kensaki.
6. The kendama according to claim 1, wherein at least one
attachable and detachable member is of providing a string hole
connecting the string to the tip portion of the kensaki.
7. The kendama according to claim 1, wherein at least one
attachable and detachable member is of connecting a kensaki of
another kendama to the tip portion of the kensaki.
8. The kendama according to claim 1, wherein at least one
attachable and detachable member is of attaching a small camera to
the tip portion of the kensaki.
9. The kendama according to claim 1, wherein a fitting and
inserting hole is provided on a tip end plane of the base end of
the kensaki, the attachable and detachable member has a shaft
portion to be inserted and fitted to the fitting and inserting
hole.
10. The kendama according to claim 9, wherein a retaining portion
is provided on the shaft portion, the retaining portion is
configured by annularly providing an elastic protrusion along an
outer peripheral face of the shaft portion.
11. The kendama according to claim 1, wherein a shaft portion is
provided on a tip end plane of the base end of the kensaki, the
attachable and detachable member is provided with as fitting and
inserting hole to insert and it the shaft portion.
12. The kendama according to claim 11, wherein a thread groove is
provided on an inner peripheral face of the fitting and inserting
hole of the attachable and detachable member, the thread groove
threadably mounts an outer peripheral face of the shaft portion on
the base end of the kensaki.
13. The kendama according to claim 9, a weight member is contained
in the fitting and inserting hole to adjust a weight of the
kensaki.
14. The kendama according to claim 11, a weight member is contained
in the fitting and inserting hole to adjust a weight of the
kensaki.
Description
TECHNICAL FIELD
[0001] The present invention relates to a kendama.
BACKGROUND ART
[0002] Kendama is a toy enjoyed through the ages. The number of
people recently increases who play kendama as a game. Kendama has
various shapes. However, one including a sword 100 (ken), a ball
200 (tama), and a string 300, for example see patent document 1, is
common in contemporary Japan. FIG. 17 is a front view illustrating
a common kendama existing before. The ken 100 has a shape of a
cross in front view configured by a sword shaft 110 (kenjiku)
having a shape of a stick and a cross-piece 120 (sarado) having a
shape of a tsutsumi (Japanese hand drum). A portion 111 protruding
to an upper side than the cross-piece 120 in the sword shaft 110 is
referred to as a "kensaki" (tip of sword). The tama 200 is provided
with a hole 210 for inserting the kensaki 111. A large cup 121 is
provided on as plane of one end of the cross-piece 120. A small cup
122 is provided on a plane of another end of the cross-piece 120. A
middle cup 116 is provided on a lower end plane of the sword shaft
110. The large cup 121, the small cup 122, and the middle cup 116
are configured to be able to receive the ball 200. Japanese Kendama
Association, which holds lots of kendama contests, certifies the
kendama having as shape illustrated in FIG. 17 as an official
one.
[0003] However, a prior kendama is problematic in that a tip
portion of the kensaki 111 is easy to be worn by an impact given by
the ball and others. Players who play kendama as a game have to
uneconomically buy new kendama as a whole if the kensaki 111 is
worn even though other portions are intact. A balance of weight of
the sword 110 and others affect a difficulty of techniques,
especially a difficulty of swinging type techniques such as a
"Hikoki (air plane)" in which the ball 200 is supported and the
sword 110 is swung. However, the balance of weight cannot be
adjusted in a prior kendama. Difficulty of a specific technique
cannot be make both or low. It is impossible to gradually shift to
as balance of weight of lower difficulty to a balance of weight of
high difficulty in order to master a specific technique. Since many
techniques are already existing, developing new techniques is in an
extent of minor changing existing techniques. It is difficult to
develop a novel techniques with as prior kendama.
[0004] Kendama having a configuration that a portion corresponds to
the kensaki is attached or detached is proposed before. A set of
industrial tools having a shape of kendama in which kinds of bit
are attached to a chuck (8) provided on a tip of bit attaching
portion (7) is illustrated in FIG. 1 of Patent Document 2. However,
the bit attached to the chuck (8) is a cross slot screwdriver,
straight slot screw driver or others, which are attached when it is
used as an industrial tool, and which are not used as the kensaki
when it is used as a kendama. A toy having a ball is illustrated in
FIG. 1 of Patent Document 3, in which a ball receiver () is screwed
on an upper end of a shaft (). However, a portion corresponding to
the kensaki is a pointed shaft (). Patent Document 3 is silent
about making the pointed shaft () attachable and detachable.
[0005] Kendama is illustrated in FIG. 3 of Patent Document 4, in
which a horn (7) is fitted into a middle portion of an upper face
of a cross-piece. However, if a configuration of fitting the horn
(7) into the cross-piece is adapted, the horn is possibly dropped
when a ball (1) hits the horn (7). In addition, Patent Document 4
is silent about exchanging horn (7) with another member. A to
having a ball is illustrated in Figs of Patent Document 5, in which
a kensaki (6) is screwed into a middle portion of a ball receiver
(1) having a shape of a tsutsumi (Japanese hand drum). Patent
Document 5 is also silent about exchanging the kensaki (6) with
another member. Balance of weight of the sword cannot be adjusted
with kendamas disclosed in Patent Documents 2 to 5.
PRIOR ARTS
Patent Document
[0006] Patent Document 1: Japanese Patent Application Publication
No. 2002-346011
[0007] Patent Document 2: Japanese Utility Patent Application
Publication No. H01-132383
[0008] Patent Document 3: Japanese Utility Patent Examined
Application Publication No. S03-007398
[0009] Patent Document Japanese Patent Application Publication No.
2002-360754
[0010] Patent Document 5: Japanese Utility Patent Examined
Application Publication No. S12-016699
DISCLOSURE OF THE INVENTION
Problem to be Solved by the Invention
[0011] Present invention is to solve the problem described above.
The present invention provides a kendama realizing; [0012] (1)
replacing only a kensaki if the kensaki is worn, [0013] (2)
adjusting a balance of weight and others of a sword, [0014] (3)
developing a novel technique largely different from existing
techniques.
Means to Solve the Problems
[0015] The problems are solved by a kendama. The kendama includes a
sword having a sword shaft and as cross-piece; a ball having a hole
of inserting a kensaki protruding to an upper side than the
cross-piece in the sword shaft; as string connecting the sword and
the ball. A tip portion of the kensaki is configured as an
attachable and detachable member which is attachable and detachable
with respect to a base end of the kensaki. The attachable and
detachable member is a plurality of attachable and detachable
members replaced each other.
[0016] Although all of the plurality of attachable and detachable
members are the same (members for replacing a first attachable and
detachable member is worn), it is preferable that at least two
attachable and detachable members out of the plurality of
attachable and detachable members differ in at least any one item
or more items out of a weight, shape, and color. According to this,
difficulty of a technique using the kendama is changed and a novel
technique is performed by adjusting a balance of weight, and/or
changing the shape and/or color of the sword.
[0017] For example, as for the shape, it is preferable that the
plurality of attachable and detachable member is configured as
follows. [0018] (1) At least one attachable and detachable member
is of configuring a shape of the tip portion of the kensaki as a
hemisphere or circular cone. The attachable and detachable member
having this configuration is sometimes referred to as "standard
attachable and detachable member". [0019] (2) At least one
attachable and detachable member is of configuring as shape of the
tip portion of the kensaki as a circular truncated cone (top
portion of the standard attachable and detachable member is
truncated). The attachable and detachable member having this
configuration is sometimes referred to as "truncated attachable and
detachable member". [0020] (3) At least one attachable and
detachable member is of providing as slit groove catching the
string with the tip portion of the kensaki. The attachable and
detachable member having this configuration is sometimes referred
to as "attachable and detachable member having slit groove". [0021]
(4) At least one attachable and detachable member is of providing a
string hole connecting the string to the tip portion of the
kensaki. The attachable and detachable member having this
configuration is sometimes referred to as "attachable and
detachable member having string hole". [0022] (5) At least one
attachable and detachable member is of connecting a kensaki of
another kendama to the tip portion of the kensaki. The attachable
and detachable member having this configuration is sometimes
referred to as "connecting type attachable and detachable member".
[0023] (6) At least one attachable and detachable member is of
attaching a small camera to the tip portion of the kensaki. The
attachable and detachable member having this configuration is
sometimes referred to as "attachable and detachable member embedded
with camera". The standard attachable and detachable member, the
truncated attachable and detachable member, the attachable and
detachable member having slit groove, the connecting type
attachable and detachable member, and the attachable and detachable
member embedded with camera are explained in detail later.
[0024] As long as the attachable and detachable member is a
attachably and detachably attached to the base end of the kensaki,
specific configurations are not particularly limited in the present
invention. However, it is preferable that a fitting and inserting
hole is provided on a tip end plane of the base end of the kensaki,
and the attachable and detachable member has a shaft portion to be
inserted and fitted to the fitting and inserting hole. In this
case, it is preferable that a retaining portion is provided on the
shaft portion, and the retaining portion is configured by annularly
providing an elastic protrusion along an outer peripheral face of
the shaft portion. Alternatively, it is preferable that a shaft
portion is provided on the tip end plane of the base end of the
kensaki, and the attachable and detachable member has a fitting and
inserting hole to insert and fit the shaft portion. In this case,
it is preferable that a thread groove is provided on an inner
peripheral face of the fitting and inserting hole of the attachable
and detachable member, the thread groove threadably mounts an outer
peripheral face of the shaft portion on the base end of the
kensaki. By adapting these configurations, the attachable and
detachable member can be securely attached to the base end of the
kensaki and be easily attached or detached. Since the structure is
simple, a manufacturing cost of the kendama can be reduced. A
weight of the attachable and detachable member can be changed by
modifying a length of the shaft portion (see reference numeral 112b
of FIG. 2 and FIG. 5) without modifying material of the attachable
and detachable member and as shape of a portion (head portion)
appeared outside when the attachable and detachable member is
attached to the kensaki.
[0025] In case the fitting and inserting hole is provided on tip
end plane of the base end of the kensaki or the fitting and
inserting hole is provided on the attachable and detachable member,
it is preferable that a weight member (see reference numeral 400 of
FIG. 6) is contained in the fitting and inserting hole to adjust a
weight of the kensaki. The weight of the kensaki is changed to
adjust a balance of weight of the kensaki by selecting an existence
or non-existence, or a kind and the number of the weight member. In
this case, if the weight member is directly inserted, a trouble
possibly occurs such as a rattling sound generated by the weight
member vibrating in the fitting and inserting hole, or an
instability of the balance of weight of the sword, it is preferable
that a cushioning material (see reference numeral 500 of FIG. 6) is
contained at a bottom portion of the fitting and inserting
hole.
Effects of the Invention
[0026] According to the present invention, a kendama realizing
following is provided; [0027] (1) replacing only a kensaki if the
kensaki is worn, [0028] (2) adjusting a balance of weight and
others of a sword, [0029] (3) developing a novel technique largely
different from existing techniques.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a front view illustrating a kendama of a present
invention in which a standard attachable and detachable member is
attached to a kensaki.
[0031] FIG. 2 is a magnified view illustrating a flow of attaching
a standard attachable and detachable member to a tip portion of a
kensaki, according to the present invention.
[0032] FIG. 3 is a magnified view illustrating a flow of attaching
a standard attachable and detachable member having a different
color to a tip portion of a kensaki, according to the present
invention.
[0033] FIG. 4 is a magnified view illustrating a flow of attaching
a standard attachable and detachable member having a shaft portion
provided with a thread ridge to a tip portion of a kensaki,
according to the present invention.
[0034] FIG. 5 is a magnified view illustrating a flow of attaching
a standard attachable and detachable member having a shaft portion
of a different size to a tip portion of a kensaki, according to the
present invention.
[0035] FIG. 6 is a magnified view illustrating a flow of making a
fitting and inserting hole provided on a base end of a kensaki
contain a weight member, according to the present invention.
[0036] FIG. 7 is a drawing explaining a difficulty change brought
by a change of balance of weight when performing as technique
called "Getsumen Chakuriku (landing on the moon)".
[0037] FIG. 8 is a drawing explaining a difficulty change brought
by a change of balance of weight when performing a technique called
"Hikoki (air plane)".
[0038] FIG. 9 is a drawing explaining a difficulty change brought
by a change of balance of weight when performing a technique called
"Toudai (beacon)".
[0039] FIG. 10 is a magnified view illustrating a flow of attaching
a truncated attachable and detachable member to a tip portion of a
kensaki, according to the present invention.
[0040] FIG. 11 is a magnified view illustrating a flow of attaching
an attachable and detachable member having slit groove to a tip
portion of a kensaki, according to the present invention.
[0041] FIG. 12 is a drawing illustrating a state in which a
technique is performed using a kendama attached with the attachable
and detachable member having slit groove.
[0042] FIG. 13 is as magnified view illustrating a flow of
attaching an attachable and detachable member having string hole to
a tip portion of a kensaki, according to the present invention.
[0043] FIG. 14 is a magnified view illustrating a flow of attaching
a connecting type attachable and detachable member to a tip portion
of a kensaki, according to the present invention.
[0044] FIG. 15 is as drawing illustrating a state in which the
connecting type attachable and detachable member is attached to the
kensaki to connect each kensaki of two kendamas.
[0045] FIG. 16 is a magnified view illustrating a flow of attaching
an attachable and detachable member embedded with camera to a tip
portion of a kensaki, according to the present invention.
[0046] FIG. 17 is a front view illustrating a common kendama
existing before.
[0047] FIG. 18 is a magnified view illustrating a flow of attaching
a standard attachable and detachable member having a fitting and
inserting hole provided with a thread groove to a tip portion of a
kensaki, according to the present invention.
EMBODIMENTS FOR CARRYING OUT THE INVENTION
[0048] Embodiments of kendama of a present invention is more
specifically explained below with reference to Figures.
[0049] [Outline of an Embodiment of Kendama]
[0050] FIG. 1 is a front view illustrating a kendama of a present
invention in which a standard attachable and detachable member 112
is attached to a kensaki 111. The kendama of the present embodiment
is configure by a sword 100, a ball 200, and a string 300. The
sword 100 is configured by a sword shaft 110, and a cross piece
120. The ball 200 is provided with a hole 210 of inserting a
kensaki 111 protruding to an upper side than the cross-piece 120 in
the sword shaft 110. A tip portion of the kensaki 111 is configured
as an attachable and detachable member 112 which is attachable and
detachable with respect to a base end of the kensaki 111.
[0051] The kendama of the present embodiment is provided with six
kinds as the attachable and detachable members 112, which are a
standard attachable and detachable member 112 (FIG. 2), a truncated
attachable and detachable member 112 (FIG. 10), an attachable and
detachable member 112 having slit groove (FIG. 11), an attachable
and detachable member 112 having string hole (FIG. 13), a
connecting type attachable and detachable member 112 (FIG. 14), and
an attachable and detachable member 112 embedded with camera (FIG.
16). These six attachable and detachable members 112 are
interchanged each other. These six attachable and detachable
members 112 are specifically explained later. These six attachable
and detachable members 112 are an example. Some of these attachable
and detachable members 112 may be omitted, or an attachable and
detachable member 112 other than the six kinds of attachable and
detachable members 112 may be added to.
[0052] Although a string hole 123 connecting the string 300 to the
sword 100 side is provided on an slight upper side than a center
with respect to width and upper and lower direction of the cross
piece 120 in as common kendama as illustrated in FIG. 17, it is
provided on a position where a base of the kensaki 111 and the
cross-piece 120 connect. By providing the string hole 123 on upper
side than a common kendama, friction given to the string 300 from
the sword is reduced to prevent the string 300 from breaking. It
facilitates one to perform techniques called "Hikoki" and "Toudai"
explained later because balance of the sword 100 is improved.
Difficulty of techniques can also be changed by shifting leftwardly
or rightwardly position of the string hole from the center with
respect to width and upper and lower direction of the cross piece
120.
[0053] [Standard Attachable and Detachable Member]
[0054] The six kinds of attachable and detachable members 112 are
explained below in sequence. First, the standard attachable and
detachable member 112 is explained. The standard attachable and
detachable member 112 is provided with a head portion 112a having a
hemispheric shape, and as shaft portion 112b extending from the
head portion 112a to a lower side as illustrated in FIG. 2. FIG. 2
is a magnified view illustrating a flow of attaching the standard
attachable and detachable member 112 to the tip portion of the
kensaki 111. In FIG. 2, the kensaki 111 is illustrated as a cross
section cut on a plane on which a center axis lies (FIGS. 3 to 6,
10, 11, 13, 14, and 16 are illustrated in a same manner). In a
common kendama certified by Japanese Kendama Association as a
official one, shape of a tip portion of as kensaki 111 is
hemispheric (or a circular cone). By attaching the standard
attachable and detachable member 112 to the kensaki 111, the tip of
the kensaki 111 becomes a hemispheric shape to be used as a common
kendama such as one illustrated in FIG. 17. It is preferable that
plurality of the standard attachable and detachable member is
provided since it is used very often and tend to be worn.
[0055] The head portion 112a is exposed outer side after the
attachable and detachable member 112 is attached to the kensaki
111. Although Color of the head portion 112a is normally the same
as the kensaki 111, it is preferable that various ones having
different colors are provided even though attachable and detachable
members 112 belong to the same type, as illustrated in FIG. 3. FIG.
3 is a magnified view illustrating a flow of attaching a standard
attachable and detachable member 112 having a different color to a
tip portion of a kensaki 111. By changing a color of the head
portion 112a, difficulty of techniques can be changed. For example,
if an outstanding color such as red is adapted, the head portion
112a becomes more outstanding than other portions to facilitate one
to successfully perform a technique in which the kensaki 111 is
inserted into the hole 210 of the ball 200.
[0056] Material of the head portion 112a is not particularly
limited if it has a sufficient strength as the tip portion of the
kensaki 111. Plastics, rubbers, metals, woods are exemplified as
material of the head portion 112a. It is not particularly
problematic if material easy to be worn such as woods is used since
the kendama of the present embodiment is maintained by
interchanging the attachable and detachable member 112. In the
present embodiment, all of the head portions 112a of the attachable
and detachable members 112 are made of polyethylene, which is
inexpensive and easy to shape. However, if the weight of a tip
portion of the kensaki 111 is made adjustable, various ones having
different densities are used as for the same type of the attachable
and detachable members 112 too, as in an aforementioned shaft
portion 112b.
[0057] The shaft portion 112b is explained. The shall portion 112b
is a portion to be fitted and inserted to a fitting and inserting
hole 111a provided on the kensaki 111 to attach the attachable and
detachable member 112 to the kensaki 111. The shaft portion 112b is
not particularly limited if it has a structure to be fitted and
inserted and fixed to the fitting and inserting hole 111a. For
example, the fitting and inserting hole 111a may be a threaded hole
and a thread ridge 112d may be provided on an outer peripheral face
of the shaft portion 112b to screw the attachable and detachable
members 112 to as tip portion of a kensaki 111 as illustrated in
FIG. 4. FIG. 4 is a magnified view illustrating a flow of attaching
a standard attachable and detachable member 112 having a shaft
portion provided with a thread ridge 112d to at tip portion of it
kensaki 111. According to a threadably mounting structure of FIG.
4, if a standard attachable and detachable member 122c having a
pattern or a standard attachable and detachable member 122c having
a head portion 112a whose shape is different depending on a
direction is used, the head portion 112a does not come to desired
direction when screwing a shall potion 112b to a fitting and
inserting hole 111a, unless thread groove of the fitting and
inserting hole 111a and the thread ridge 112d of the shaft portion
112b are processed at high accuracy. This is not much problematic
if a standard attachable and detachable member having no pattern is
used. Considering this, a shaft portion 112b is made as follows in
the kendama of the present embodiment.
[0058] The shaft portion 112b is provided with a retaining portion
112c instead of the thread ridge as illustrated in FIG. 2. The
inserting and fitting hole 111a is not the threaded hole. The
retaining portion 112c is configured by annularly providing an
elastic protrusion along an outer peripheral face of the shaft
portion 112b, and closely contacts to an inner peripheral face of
the fitting and inserting hole 111a when the shaft portion 112b is
fitted and inserted into the fitting and inserting hole 111a to
prevent the shaft portion 112b from being dropped out of the
fitting and inserting hole 111a. The retaining portion 112c is
normally made of elastic materials such as rubbers. If the shaft
portion 112b and the retaining portion 112c are made of the same
material, the retaining portion 112c and the shaft portion 112b may
be integrally formed at the same time. If they are formed of
different materials, the retaining portion 112c and the shaft
portion 112b are formed as separate body. In this case, the
retaining portion 112c is provided by externally fitting to the
shaft portion 112c or integrally shaping a different material with
respect to the shaft portion 112c. In this case, the retaining
portion 112c is prevented from being dropped out of the shaft
portion 112b by circularly providing a groove on the outer
peripheral face of the shaft portion 112b and positioning the
retaining portion 112c at this portion.
[0059] A cross sectional shape perpendicular to a longitudinal
direction of the fitting and inserting hole 111a and the shaft
portion 112b is a true circle in the kendama of the present
embodiment. However, if it is necessary to prevent an attachable
and detachable member 112 from rotating with respect to the kensaki
111 after the attachable and detachable member 112 is attached to
the kensaki 111, the cross sectional shape of the shaft portion,
112b and the fitting and inserting hole 111a may be as non-circular
shape such as a polygonal shape, an oval shape, or others.
According to this configuration, a shaft portion 112b of an
attachable and detachable member attached to as tip portion of a
kensaki 111 is prevented from rotating by engaging a shaft portion
112b to an fitting and inserting hole 111a. This configuration is
not adaptable in the threadably mounting structure of FIG. 4, and
becomes adaptable with a shaft portion 112b having as fitting and
inserting structure as illustrated in FIG. 2. This configuration is
preferably adapted if an attachable and detachable member 112
should not be rotated such as when using the attachable and
detachable member 112 having slit (FIG. 11) or the connecting type
attachable and detachable member 112 which are explained later.
[0060] Materials of the shaft portion 112b is not particularly
limited if it has a sufficient strength. Plastics, rubbers, metals,
woods are exemplified as materials of the shaft portion 112b. The
shaft portion 112b may be made of a material an as the head potion
112b, or may be made of a different material. In the kendama of the
present embodiment, as for the standard detachable and detachable
members 112, three kinds are provided, one of which is a light
weight type whose shaft portion 112b is made of polyethylene
another is a middle weight type whose shaft portion 112b is made of
a plastic of acrylonitrile butadiene styrene (ABS), the other is
heavy weight type whose shaft portion 112b is made of a plastic of
polyoxymethlene (Duracon, registered trademark). The shaft portion
112b is made heavier by shaping the shaft portion 112b with a metal
or embedding a heavy material such as metals to an inside of the
shaft portion 112b. Weight of the tip portion of the kensaki 111
can be adjusted by providing various ones having shaft portions 112
differed in a weight even with the same type attachable and
detachable members 112.
[0061] Weight of the tip portion of the kensaki 111 is also
adjusted by providing various ones having a different size such as
a length of the shaft portion 112b even with the same type
attachable and detachable member 112, as illustrated in FIG. 5.
FIG. 5 is as magnified view illustrating a flow of attaching a
standard attachable and detachable member 112 having a shaft
portion 112b of a different size to a tip portion of a kensaki 111.
Weight of a tip portion of a kensaki 111 is also adjusted by
containing a weight member 400 in a fitting and inserting hole 111a
as illustrated in FIG. 6. FIG. 6 is a magnified view illustrating a
flow of making a fitting and inserting hole 111a provided on a base
end of a kensaki 111 contain a weight member 400. In this case, if
the weight member 400 is directly inserted, a trouble possibly
occurs such as a rattling sound generated by the weight member 400
vibrating in the fitting and inserting hole 111, or an instability
of the balance of weight of the sword 110, it is preferable that a
cushioning material 500 (see reference numeral 500 of FIG. 6) is
contained at a bottom portion of the fitting and inserting hole
111a.
[0062] The case is explained so far, in which the shaft portion
112b of the attachable and detachable member 112 is fitted and
inserted into the fitting and inserting hole 111a of the tip
portion of the kensaki 111. Relationship between the shaft portion
112b and the fitting and inserting hole 111a is interchanged. A
shall portion 111b is provided on a tip end plane of the base end
of a kensaki 111, as illustrated in FIG. 18. An attainable and
detachable member 112 is provided with a fitting and inserting hole
112i. By fitting and inserting the shaft portion 111b to the
fitting and inserting hole 112i, the attachable and detachable
member 112 is attached to the kensaki 111. FIG. 18 is as magnified
view illustrating a flow of attaching the standard attachable and
detachable member 112 having a fitting and inserting hole 112i
provided with a thread groove 112j to a tip portion of as kensaki
111. In this case, if a thread groove 112j is provided on an inner
peripheral face of the fitting and inserting hole 112i which
threadably mounts an outer peripheral face of the shaft portion
111b, the attachable and detachable member 112 can be screwed on
the kensaki 111. In this case, a threaded shaft is used as the
shaft portion 111b.
[0063] As explained above, balance of weight of the sword 100 is
adjusted even with the same type attachable and detachable member
112 (for example with the same standard attachable and detachable
member 112) by selecting a head portion 112a, materials or size of
the shaft potion 112b, a kind or existence or non-existence of the
weight member 400 to change a weight of the kensaki 111. Difficulty
of a specific technique is changed by selecting an attachable and
detachable member 112 or as weight member to be used without
changing a kendama to be used. Difficulty change of technique
brought by change of balance of weight of a sword is explained
below raising examples.
[0064] For example, there is a technique called "Getsumen Chakuriku
(landing on the moon)", which is included in a hundred chosen
techniques by Japan Kendama Association. Getsumen Chakuriku is a
technique in which the ball 200 is held, a sword 100 is swung to
upside, the sword 10 is put on the ball 200 so that a large cup 121
(or a small cup 122) of a cross-piece 120 contacts to the ball 200
as illustrated in FIG. 7. FIG. 7 is a drawing explaining a
difficulty change brought by a change of balance of weight when
performing Getsumen Chakuriku. If the kensaki 111 is heavy when
performing Getsumen Chakuriku, weight of the sword 100 on the ball
200 is balanced at relatively horizontal laid position since a
weight center of the sword 100 shifts to the kensaki 111 side, as
illustrated in left side of FIG. 7. This facilitates one to
successfully perform the technique. In contrast to this, if the
kensaki is light, weight of the sword 100 on the ball 200 is
balanced at relatively vertical standing position since a weight
center of the sword 100 shifts to a kenjiri (base end of a sword)
114 side, as illustrated in right side of FIG. 7. This prevents one
from successfully performing the technique.
[0065] There is a technique called "Hikoki (air plane)" in the
hundred chosen techniques by Japan Kendama Association. Hikoki is a
technique in which as ball 200 is held with a hole 210 facing an
upper side, a sword 100 is swung up half (or swung plural times) to
be inverted by making the ball 200 as a center, its kensaki 111 is
inserted into the hole 210, as illustrated with arrow A in FIG. 8.
FIG. 8 is a drawing explaining a difficulty change brought by a
change of balance of weight when performing a technique called
"Hikoki". If the kensaki 111 is heavy when performing Hikoki, an
angular velocity of the sword 100 becomes high when swinging up the
sword 100 (rotating rate becomes high) since a weight center of the
sword 100 becomes close to a rotation center (the ball 200) of the
sword 100. This prevents one from successfully performing the
technique. In contrast to this, if the kensaki is light, an angular
velocity of the sword 100 becomes low when swinging up the sword
100 (rotating rate becomes low) since a weight center of the sword
100 becomes away from a rotation center (the ball 200) of the sword
100. This facilitates one to successfully perform the
technique.
[0066] There is a technique called "Toudai (beacon)" the hundred
chosen techniques by Japan Kendama Association. Toudai is a
technique in which a ball 200 is held, a sword 100 is lifted up,
the sword 10 is put on the ball 200 so that a middle cup 116
contacts to the ball 200 as illustrated with arrow B in FIG. 9.
FIG. 9 is a drawing explaining as difficulty change brought by a
change of balance of weight when performing a technique called
"Toudai". If a kensaki 111 is heavy when performing Toudai, a
posture of the pulled up sword 100 becomes unstable since a weight
center of the sword 100 comes to high position. This prevents one
from successfully performing the technique. In contrast to this, if
the kensaki 111 is light, a posture of the pulled up sword 100
becomes stable since a weight center of the sword 100 comes to
lower position. This facilitates one to successfully perform the
technique.
[0067] Of course, according to kendama of the present embodiment,
difficulty of techniques other than Getsumen Chakuriku, Hikoki, and
Toudai can be changed. As explained, according to the kendama of
the present embodiment, difficulty of techniques can be changed to
enjoy them. The number of steps modifying weight (total weight of
an attachable and detachable member 112 and a weight member 400) of
the tip portion of the kensaki 111 is not particularly limited. It
is normally two steps or more, and preferably three steps or more,
and not more than ten to twenty steps. Adjusting range of a weight
of a tip portion (an attachable and detachable member 112) of a
kensaki 111 is not particularly limited, either. It is normally 1
to 100 g, and is preferably 3 to 50 g, and is more preferably 5 to
20 g. Weight adjusting width (adjusting weight by how much gram) is
not particularly limited, either. It is normally by 0.5 g or more,
and is preferably 1 g or more, and not more than by 50 to 100 g or
so.
[0068] [Truncated Attachable and Detachable Member]
[0069] The truncated attachable and detachable member 112 is
explained hereafter. FIG. 10 is a magnified view illustrating a
flow of attaching the truncated attachable and detachable member
112 to the tip portion of the kensaki 111. The truncated attachable
and detachable member 112 configures its head portion 112a as a
circular truncated cone as illustrated in FIG. 10. In other words,
the head portion 112a of the truncated attachable and detachable
member 112 has a shape truncating top portion of the head portion
112b (see FIG. 2) of a standard attachable and detachable member
112. The tip portion of the kensaki 111 becomes a shape of a
circular truncated cone by attaching the truncated attachable and
detachable member 112. Novel techniques, which cannot be performed
with a common kendama can be performed, such as a technique in
which the ball 200 is put on the tip portion of the kensaki 111, a
technique making the inverted sword stand on the ball 200 (a
technique in which a tip portion of a kensaki 111 is put on a ball
200), or a technique making the inverted sword stand on a hand or a
finger (a technique in which the up portion of the kensaki 111 is
put on a hand or a finger). A top portion of the truncated
attachable and detachable member 112 spherically concaves at a
radius of curvature same as the ball 200 to facilitate to receive
the ball 200 with the portion, according to the kendama of the
present embodiment. Since configurations, which are not
specifically referred here such as a structure of a shaft portion
112b of the truncated attachable and detachable member 112 and
materials consisting each portions, is same as those of the
standard attachable and detachable member 112 explained above, an
explanation is omitted.
[0070] [Attachable and Detachable Member Having Slit Groove]
[0071] The attachable and detachable member 112 having slit groove
is explained hereafter. FIG. 11 is a magnified view illustrating a
flow of attaching the attachable and detachable member having slit
groove to the tip portion of the kensaki. FIG. 12 is a drawing
illustrating a state in which a technique is performed using a
kendama attached with the attachable and detachable member having
slit groove. As illustrated in FIG. 11, in the attachable and
detachable member 112 having slit groove, its head portion 112a is
provided with a slit groove 112e. The slit groove 112a is provided
along an upper face of the head potion 112a from a front side to a
rear side of the head portion 112a. As illustrated in FIG. 12, the
slit groove 112e makes it possible to catch the string 300 and to
performing novel technique applying this. Since configurations,
which are not specifically referred with respect to the attachable
and detachable member 112 having slit groove such as a structure of
a shall portion 112b of the attachable and detachable member 112
having slit groove and materials consisting each portions, are same
as those of the standard attachable and detachable member 112
explained above, an explanation is omitted. The attachable and
detachable member 112 having slit groove may be combined with the
truncated attachable and detachable member 112 to make a hybrid
type.
[0072] [Attachable and Detachable Member Having String Hole]
[0073] The attachable and detachable member 112 having string hole
is explained hereafter. FIG. 13 is a magnified view illustrating a
flow of attaching the attachable and detachable member 112 having
string hole to the tip portion of the kensaki 111. As illustrated
in FIG. 13, the attachable and detachable member 112 is provided
with a string hole 112f perforating a head portion 112a from one
side to other side. As illustrated in as drawing on right side, the
string 300 is connected to make a loop. By fixing an end portion of
the string 300 on the sword 100 side to the string hole 112f
provided on the kensaki 111, kendama is enjoyed in a feeling
different from a common kendama (FIG. 17) in which an end portion
of a string 300 on a sword side is fixed to the cross-piece 120.
According to this, novel techniques can be performed with the
kendama. Since other configurations, which are not specifically
referred with respect to the attachable and detachable member 112
having string hole such as a structure of a shaft portion 112b of
the attachable and detachable member 112 having string hole and
materials consisting each portions, are same as those of the
standard attachable and detachable member 112 explained above, an
explanation is omitted. The attachable and detachable member 112
having string hole may be combined with the truncated attachable
and detachable member 112 or the attachable and detachable member
122 having slit groove to make a hybrid type.
[0074] [Connecting Type Attachable and Detachable Member]
[0075] The connecting type attachable and detachable member 112 is
explained hereafter. FIG. 14 is a magnified view illustrating a
flow of attaching the connecting type attachable and detachable
member 112 to the tip portion of the kensaki 111. FIG. 15 is a
drawing illustrating a state in which the connecting type
attachable and detachable member 112 is attached to the kensaki 111
to connect each kensaki 111 of two kendamas. In as portion where
the kensaki 111 and its vicinity are illustrated as magnified
manner in FIG. 15, the kensaki 111 is illustrated as a cross
section cut on a plane on which a center axis lies. The connecting
type attachable and detachable member 112 has a configuration of a
shaft portion 112b being extended until a portion corresponding to
the head portion 112a of the standard attachable and detachable
member 112, an upper half of the shaft portion 112b projecting out
of a fitting and inserting hole 111a when the shaft portion 112b
being fitted and inserted into the fitting and inserting hole 111a,
as illustrated in FIG. 14. The tip portion of the kensaki 111 of
one kendama can be connected to a tip portion of a kensaki 111 of
another kendama. According to this, novel techniques, which cannot
be performed with a common kendama, can be performed. Since other
configurations, which are not specifically referred with respect to
the connecting type attachable and detachable member 112 such as a
structure of a shaft portion 112b of the connecting type attachable
and detachable member 112 and materials consisting each portions,
are same as those of the standard attachable and detachable member
112 explained above, an explanation is omitted.
[0076] [Attachable and Detachable Member Embedded with Camera]
[0077] Finally, the attachable and detachable member 112 embedded
with camera is explained. FIG. 16 is a magnified view illustrating
a flow of attaching the attachable and detachable member 112
embedded with camera to a tip portion of as kensaki 111. As
illustrated in FIG. 16, in the attachable and detachable member 112
embedded with a camera, its head portion 112a is embedded with a
small camera 112g to take a movie at an eye point of as top portion
of the head portion 112a. This makes it possible to take a movie of
a technique of kendama at a novel eye point not existing before. A
cable 112h, which supply a power to the small camera 112g or
outputting data of a movie taken with the small camera 112g, is
extending from a lower end portion of the small camera 112g. The
cable 112h goes through a shaft portion 112b of the attachable and
detachable member 112 to be contained in a fitting and inserting
hole 111a. A power source supplying the small camera 112g (not
illustrated in Figs.) with a power and a memory (not illustrated in
Figs.) storing data of movies taken with the small camera 112g can
be contained in a cavity portion of a sword shaft 110 or as a
cross-piece 120. Since other configurations, which are not
specifically referred with respect to the attachable and detachable
member 112 embedded with camera such as a structure of a shaft
portion 112b of the attachable and detachable member 112 embedded
with camera and materials consisting each portions, are same as
those of the standard attachable and detachable member 112
explained above, an explanation is omitted. The attachable and
detachable member 112 embedded with camera may be combined with the
truncated attachable and detachable member 112, the attachable and
detachable member 112 having a slit groove, or the attachable and
detachable member 112 having string hole to make a hybrid type.
REFERENCE NUMERALS
[0078] 100 sword [0079] 110 sword shaft [0080] 111 kensaki [0081]
111a fitting and inserting hole [0082] 111b shaft portion [0083]
112 attachable and detachable member [0084] 112a head portion
[0085] 112b shaft portion [0086] 112c retaining portion [0087] 112d
thread ridge [0088] 112e slit groove [0089] 112f string hole [0090]
112g small camera [0091] 112h cable [0092] 112i fitting and
inserting hole [0093] 112j thread groove [0094] 114 kenjiri [0095]
115 slip-stop [0096] 116 middle cup [0097] 116a middle cup rim
[0098] 120 cross-piece [0099] 121 large cup [0100] 121a large cup
rim [0101] 122 small cup [0102] 122a small cup rim [0103] 123
string hole [0104] 200 ball [0105] 210 hole [0106] 300 string
[0107] 400 weight member [0108] 500 cushioning material
* * * * *