BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates to a toy top and, more particularly, to a toy top with
an operation characteristic on a playing board changed at a point between the first
half and the latter half of spinning of the toy top.
2. Description of the Related Art
[0002] Conventionally, a toy top capable of changing an operation mode by rearranging component
members was proposed by the assignee of the present application (refer to, for example,
Japanese Utility Model Registration No.
3149383) and has been in practical use. This toy top is configured by layering an upper layer
member with a function of attacking an opponent toy top, a middle layer member that
determines the height of the toy top, and a lower layer member that determines a movement
mode of the toy top on a playing board. A number of lower layer members are prepared
with shaft bodies having different shapes formed to protrude downward. By the replacement
of one of the lower layer members with another one with a shaft body having a shape
different from that of the former one, the operation mode on the playing board can
be changed.
[0003] Also, a toy top whose operation mode is changed depending on a rotation speed was
proposed (refer to, for example, Japanese Utility Model Registration No.
3092120). This toy top is provided therein with a shaft portion having a retractable shaft
body inside and a pair of sliding members disposed symmetrically about the shaft body.
When these sliding members make a sliding movement outward due to a centrifugal force
to move the shaft body downward, a lower end of the shaft body protrudes downward
from the shaft portion. Thus, the operation mode is changed in accordance with the
size of the outer diameter of each of the shaft portion and the shaft body.
[0004] In the above former conventional toy top, although the operation mode on the playing
board can be changed by replacing the lower layer member, the lower layer member thus
has to be changed every time the operation mode is changed, and the operation mode
cannot be changed in the course of spinning of the toy top. In the above latter conventional
toy top, although the operation mode is automatically changed in the course of spinning
of the toy top, the number of components is increased to make the structure complex,
causing the problems that production cost increases and the production process is
more difficult.
SUMMARY OF THE INVENTION
[0005] The present invention has been made in view of the abovementioned problems. Accordingly,
it is an object of the present invention to provide a novel toy top capable of changing
the operation mode in the course of spinning thereof without replacing a component
member constituting the toy top and having a simple structure and a low cost.
[0006] In order to solve the abovementioned problems, according to the present invention,
there is provided a toy top that is spun on a playing board with a playing surface
curved in a concave mirror shape. The toy top comprises a shaft portion adapted to
contact the playing surface, the shaft portion having a circumferential surface provided
with a friction portion that exhibits a coefficient of friction larger than the shaft
portion at the time of contacting the playing surface, and the shaft portion having
a tip protruding lower than the friction portion.
[0007] It is preferable that the shaft portion be formed of a resin or metal, and the friction
portion be formed of a rubber.
[0008] It is preferable that the friction portion be formed to have a cylindrical shape
and fitted around the shaft portion.
[0009] Preferably, the friction portion has a fitting hole formed to have an inner diameter
smaller than an outer diameter of the shaft portion, and the friction portion is fixed
to the shaft portion by fitting the shaft portion into the fitting hole of the friction
portion.
[0010] It is preferable that the toy top further include an upper layer member with a function
of attacking an opponent toy top, a middle layer member determining the height of
the toy top, a lower layer member fittedly attached to the middle layer member, and
a coupling member coupling together the upper layer member and the middle layer member,
wherein the lower layer member is formed to have an inverted truncated-cone shape
and has the shaft portion protruding downward.
[0011] According to the present invention, when the friction portion contacts the playing
surface at the time of high-speed rotation of the toy top, the friction portion firmly
grips the playing surface to make the toy top move around on the playing surface at
high speed. In low-speed rotation, the toy top moves to the center of the playing
surface in a concave mirror shape to continue rotation with the shaft portion of a
small coefficient of friction contacting the playing surface without moving. Therefore,
a change in rotation speed changes the operation mode of the toy top without any operation
by the user. Even though the toy top has a simple structure, the rotation speed automatically
changes the operation mode of the toy top from a dynamic attack mode to a static endurance
mode, thereby making it possible to attain a new interesting feature in a match between
toy tops.
[0012] In one embodiment of the present invention, the friction portion is formed of a rubber
with a large coefficient of friction, and the shaft portion is formed of a resin or
metal with a small coefficient of friction. Accordingly, since the friction forces
that act at the time of contacting the playing surface significantly differ from each
other, a change of the mode between an attack mode and an endurance mode can be more
clearly shown.
[0013] In one embodiment of the present invention, the friction portion is formed to have
a cylindrical shape and fitted around the shaft portion, so that the friction portion
can be easily fixed, thereby decreasing the number of components so as to simplify
the manufacturing process and reduce cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Fig. 1 is a perspective view illustrating an embodiment of a toy top according to
the present invention with a playing board having a playing surface on which the toy
top is spun;
[0015] Fig. 2 is an exploded perspective view of the toy top shown in Fig 1;
[0016] Fig. 3 is a bottom view showing an upper layer member constituting the toy top;
[0017] Figs. 4A and 4B are a plan view and a bottom view showing a middle layer member constituting
the toy top, respectively;
[0018] Fig. 5 is a plan view showing a lower layer member constituting the toy top;
[0019] Figs. 6A to 6C are an exploded bottom-side perspective view, a bottom-side perspective
view and a front view partly in section, illustrating the structure of the lower layer
member, respectively;
[0020] Figs. 7A to 7D are front views illustrating the process of assembling the toy top;
[0021] Figs. 8A and 8 are diagrams depicting the relation between a shaft portion of the
toy top and a playing surface of a playing board; and
[0022] Fig. 9A and 9B are diagrams depicting operation modes of the toy top on the playing
board.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0023] Fig. 1 depicts an embodiment of a toy top according to the present invention. This
toy top A is caused to be spun by a starter (not shown) on a playing board B with
a playing surface b curved in a concave mirror shape, to thereby play a match against
another toy top. The toy top A includes an upper layer member 1 provided with a function
of attacking the opponent toy top, a middle layer member 2 determining the height
of the toy top, a lower layer member 3 determining the operation mode of the toy top
on the playing board B, and a coupling member 4 in a screw shape coupling together
the upper layer member 1 and middle layer member 2 (see Fig. 2).
[0024] The upper layer member 1 is formed in a disk shape provided at the center thereof
with an opening 5 in which the coupling member 4 is inserted. On an outer perimeter
surface of the upper layer member 1, attacking portions 6 expanding outward are formed
to have a function of contacting the opponent toy top. On a bottom surface of the
upper layer member 1, a pair of fitting protrusions 7 protrude downward so as to be
symmetrical across the opening 5 (see Fig. 3). With these fitting protrusions 7 fitting
in recessed fitting portions 11 of the middle layer member 2 described below, assembling
of the upper layer member 1 and the middle layer member 2 is facilitated, and a freeplay
in a circumferential direction is eliminated.
[0025] The middle layer member 2 is formed in a cylindrical shape and has an inner wall
surface formed with a thread 8 to configure a screw hole 9 into which a screw 4a of
the coupling member 4 described later is screwed. Further, an upper outer perimeter
surface of the middle layer member 2 swells outward to form a swelling portion 10,
which has the pair ot recessed fitting portions 11 symmetrically formed (see Figs.
2 and 4A).
[0026] On a lower end outside surface of a cylindrical portion 12 extending downward from
the swelling portion 10 of the middle layer member 2, a pair of engaging protrusions
14 are formed that engage in openings 20 formed on the lower layer member 3 described
later (see Figs. 2 and 4B).
[0027] The lower layer member 3 is formed in an inverted truncated-cone shape made of a
small coefficient-of-friction material, such as a resin, such as hard plastic, or
metal that exhibits a small coefficient of friction in contact with the playing surface
b of the playing board B or that causes a small friction force between it and the
playing surface b, and includes a shaft portion 15 that is formed so as to protrude
downward. This shaft portion 15 is provided on a circumferential surface thereof with
a friction portion 16.
The friction portion 16 is made of a rubber material that exhibits a large coefficient
of friction in contact with the playing surface b, and is formed in a cylindrical
shape provided with a fitting hole 17 at the center thereof (see Fig. 6A). The inner
diameter of the fitting hole 17 is formed slightly smaller than the outer diameter
of the shaft portion 15 so that with this fitting hole 17 fitting around the shaft
portion 15 (shrink fitting), the friction portion 16 can be fixedly attached to the
shaft portion 15 (see Fig. 6B). The thickness of the friction portion 16 is formed
to be shorter than the length of the shaft portion 15, so that when the friction portion
16 is fixed to the shaft portion, a tip 15a of the shaft portion 15 can be set so
as to protrude lower than the friction portion 16 (see Fig. 6C).
[0028] As shown in Fig. 5, the lower layer member 3 has a pair of arc-shaped openings 20
that are symmetrically formed about the outside of the shaft portion 15 and above
the shaft portion 15. A part of the inner wall of each of these openings 20 swells
radially inward to form an engagement receiving portion 21. After the lower layer
member 3 is fitted on the middle layer member 2 from below and is rotated in a circumferential
direction, the engaging protrusions 14 of the middle layer member 2 engage with a
bottom side of each of the engagement receiving portions 21, thereby fixing the lower
layer member 3 to the middle layer member 2.
[0029] When the toy top constructed as above is assembled, the fitting protrusions 7 of
the upper layer member 1 are first fitted in the recessed fitting portions 11 of the
middle layer member 2 (see Fig. 7A).
[0030] Next, as shown in Fig. 7B, the screw 4a of the coupling member 4 is inserted through
the opening 5 from above and screwed into the screw hole 9 of the middle layer member
2, thereby fixing the upper layer member 1 to the middle layer member 2. In this state,
the upper layer member 1 is brought into pressure contact with the middle layer member
2 by the coupling member 4, so that the upper layer member 1 and the middle layer
member 2 are fixed to each other without causing backlash (see Fig. 7C).
[0031] Then, as shown in Fig. 7C, the engaging protrusions 14 formed on the cylindrical
portion 12 of the middle layer member 2 are opposed to and inserted into the openings
20 of the lower layer member 3, and then the lower layer member 3 is turned in a circumferential
direction relative to the middle layer member 2 to engage the engaging protrusions
14 with a bottom side of each of the engagement receiving portions 21, thereby constructing
the toy top A formed of the upper layer member 1, the middle layer member 2, and the
lower layer member 3 (see Fig. 7D).
[0032] When the toy top thus assembled is launched by the starter (not shown) so as to rotate
or spin at high speed onto an inclined surface portion of the playing surface b of
the playing board B (see Fig. 8A), the toy top A rotating at high speed spins upright
about the shaft portion 15 due to a gyroscopic effect. Therefore, the corner of the
tip of the friction portion 16, together with the shaft portion 15, contact the playing
surface b, and the friction portion 16 with a large coefficient of friction functions
like a rubber tire. The toy top A firmly grips the playing surface b with the friction
portion 16 so as not to slip, thereby moving (revolving) at high speed along an arc
on the playing surface b. The higher the rotational speed of the toy top A, the larger
the arc along which the toy top A moves becomes. As shown in Fig. 9A, the toy top
A makes a large movement on the playing surface b without stopping at one point, and
the operation mode is an attack mode in which the toy top A moves of its own accord
toward the opponent toy top and contacts it.
[0033] As the rotation speed of the toy top A is lessened, the radius of revolution is decreased,
and the toy top A moves to the center of the playing surface b as shown in Fig. 9B.
However, as depicted in Fig. 8B, since the friction portion 16 does not contact the
playing surface b and the tip 15a of the shaft portion 15 with a small coefficient
of friction abuts on the playing surface b at the center of the playing surface b
or in the vicinity thereof, the toy top A enters an endurance mode in which the toy
top A continues to rotate and stays at one point on the playing surface b without
traveling, while waiting for the opponent toy top to come into contact with it.
[0034] As described above, when the toy top A is launched so as to spin at high speed onto
the inclined surface portion of the playing surface b of the playing board B, the
friction portion 16 is in contact with the playing surface b. Therefore, the friction
portion 16 firmly grips the playing surface b without idle running, thereby executing
an attack mode in which the toy top A attacks the opponent toy top while revolving
at high speed. When the rotation of the toy top A is lessened, the radius of revolution
is decreased, and the toy top A soon enters a state in which it rotates at the center
of the playing surface b. At this time, since the tip 15a of the shaft portion 15
with a small coefficient of friction abuts on the playing surface b, the operation
mode changes to an endurance mode in which rotation continues.
[0035] According to the toy top A of the present invention, a toy top interesting and useful
to a player and a manufacturer can be provided even though it has a simple structure
in which the shaft portion 15 is provided with the friction portion 16, the toy top
being capable of executing an attack mode while spinning at high speed in which the
opponent toy top is actively attacked in the first half of operation, and executing
an endurance mode while spinning at reduced speed in which an attack from the opponent
toy top is waited for in the latter half of operation, thereby changing the operation
mode without having to reassemble the components or provide a complex mechanism for
detecting the rotation speed and altering the operation mode.
[0036] When the toy top A is launched onto the playing surface b of the playing board B,
the operation mode depends on the place where the toy top is launched onto the playing
surface b. More particularly, by launching the toy top onto an inclined surface portion
of the playing surface, the operation mode can be started with an attack mode, and
then be changed to an endurance mode, as described above. Furthermore, by launching
the toy top onto the center of the playing surface b, the operation mode can be an
endurance mode from the start. Therefore, whether the operation mode is initially
started with an attack mode, and is then changed to an endurance mode or the operation
mode is started with an endurance mode from the beginning can be determined by where
the toy top is launched onto the playing surface b, thereby allowing selection of
a strategically-advantageous operation mode.
1. A toy top (A) to be spun on a playing board (B) with a playing surface (b) curved
in a concave mirror shape,
characterized in that:
the toy top (A) comprises a shaft portion (15) adapted to contact the playing surface
(b), the shaft portion (15) having a circumferential surface provided with a friction
portion (16) that exhibits a coefficient of friction larger than the shaft portion
(15) at the time of contacting the playing surface (b), and the shaft portion (15)
having a tip (15a) protruding lower than the friction portion (16).
2. The toy top (A) according to claim 1, wherein the shaft portion (15) is formed of
a resin or metal, and the friction portion (16) is formed of a rubber.
3. The toy top (A) according to claim 1 or 2, wherein the friction portion (16) is formed
to have a cylindrical shape and fitted around the shaft portion (15).
4. The toy top (A) according to claim 3, wherein the friction portion (16) has a fitting
hole (17) formed to have an inner diameter smaller than an outer diameter of the shaft
portion (15), and the friction portion (16) is fixed to the shaft portion (15) by
fitting the shaft portion (15) into the fitting hole (17) of the friction portion
(16).
5. The toy top (A) according to one of claims 1 to 4, further comprising an upper layer
member (1) with a function of attacking an opponent toy top, a middle layer member
(2) determining the height of the toy top (A), a lower layer member (3) fittedly attached
to the middle layer member(2), and a coupling member (4) coupling together the upper
layer member (1) and the middle layer member(2), wherein the lower layer member (3)
is formed to have an inverted truncated-cone shape and has the shaft portion (15)
protruding downward.