-
The present invention relates to a joint structure
for a watch and a watch adopting the structure, and more
particularly to a joint structure for fastening a joint pin to
the joint portion for a watch.
-
Figs. 12 and 13 show an example of a conventional
joint method used in a watch. A long pin 34 and a short pipe 35
are used as joint members. More specifically, when a joint
portion 30 of a watch case and a joint portion 32 of a band are
coupled with each other, first of all, a hollow pipe 35 is
inserted into an insertion hole 31 of the joint portion 30 of
the case in advance. Then, the joint portion 32 of the band is
lifted and insertion holes 33 and 33 of the joint portion 32 of
the band are in alignment with the insertion hole 31 of the
joint portion 30 of the case. Then, a pin 34 is pressed into
three holes 33, 31 and 33 and thus the case and the band of the
watch are connected to each other.
-
A small annular recess 36 is formed in the middle of
the pin 34 so that the pin 34 is prevented from falling away
from the pipe 35 during use of the watch. When the joint
portions 30 and 32 are coupled with each other, the recess 36
of the pin 34 fits into a small annular recess 37 in the
middle of the pipe 35 so that the pin 34 is fixed.
-
Fig. 14 is a view showing the structure of another
conventional joint structure of a watch shown in Japanese
Patent Application Laid-Open No. Hei 08-224114. Pin insertion
holes 41 and 41 into which an insertion pin 50, having stepped
portions 53 and 53 at both ends, is inserted are formed in
bifurcated joint portions 42 and 42 of a watch case 40. A
through hole 46 having a cocoon-shaped cross-section is
provided in a joint portion 45 of the band. A spacer 47 having
the same cross-sectional shape is inserted into the through
hole 46. Also, a ring 60 having a cocoon-shaped cross-section
with a large diameter hollow portion 61 and a small diameter
hollow portion 62 divided at a waist portion 63 of the central
portion of the cross-section is inserted into hollow portions
48 and 49 of the spacer 47.
-
The large diameter hollow portion 61 of the ring 60
has an inner diameter such that large diameter portions 52 and
52 of the insertion pin 50 may be inserted loosely into the
ring 60. The small diameter hollow portion 62 has an inner
diameter that is substantially the same as a diameter of a
small diameter portion 51 of the insertion pin 50. The waist
portion 63 is formed so that it has a narrower width than the
inner diameter of the small diameter portion 62. Then, the
joint portion 45 of the band provided with the spacer 47 and
the ring 60 is inserted in between the bifurcated joint
portions 42 and 42 of the watch case 40. After the large
diameter hollow portion 61 of the ring 60 is aligned with the
pin insertion holes 41 and 41 of the bifurcated joint portions
42, the pin 50 is pushed in. Thereafter, when the watch case 40
and the band are fallen away from each other, the small
diameter portion 51 of the pin 50 is shifted to the small
diameter hollow portion 62 of the ring 60 to thereby complete
the joint work for both joint portions 42 and 45.
-
In the joint structure shown in Figs. 12 and 13, the
structure of the pin 34 and the pipe 35 is simple and its
manufacture is easy. However, when the pin 34 is inserted into
the pipe 35, it is necessary to expand the small outer diameter
portion 37 of the pipe 35, and an extremely large force is
required therefor. For this reason, the assembling work is
difficult and takes a long time. Also, if a force that is 5 kg
or greater is applied to the thin pin 34, there are problems in
structure that the pin 34 is bent, buckled or sometimes the
surface of the watch or the band would be damaged. Also, in
order to overcome the difficulty in assembling work, it is
possible to use a jig. However, the jig is specialized to
increase the cost. In addition, there is still the outstanding
problem in that the pin 34 is likely to be bent.
-
If the fixing force of the pipe 35 is weakened in
order for the pin 34 not to be bent (that is, the inner
diameter of the small outer diameter 37 of the pipe 35 is
increased), a risk that the pin 34 would be fallen away in case
of use of the watch becomes remarkable. On the other hand, if,
in order for the pin 34 not to be fallen away in case of use of
the watch, the fixing force thereof is increased, the work is
very difficult when the pin 34 is to be fallen away in order to
release the joint. Also, the small outer diameter portion 37 of
the pipe 35 is plastically deformed. The depression of the pin
34 having a larger outer diameter than the inner diameter of
the small outer diameter portion 37 of the pipe 35 is rather
difficult. In addition, in this case, the force for depressing
the pin is likely to be varied.
-
With the joint structure shown in Fig. 14 in Japanese
Patent Application Laid-Open No. Hei 08-224114, when the watch
case 40 and the joint portion 45 of the band are
attached/detached from each other, a large force is not
required therefor, and in addition, if the band and the watch
case 40 are shifted relative to each other, the
attachment/detachment may readily be completed. However, this
joint structure requires a large number of mechanical parts to
increase the cost. Also, when the joint structure is
disassembled, there is a high risk that the mechanical parts
would be lost. Also, since the space for allowing the shift of
the band has to be provided on the side of the watch case 40,
there is a restriction in design.
-
A manufacturing method for the through hole 46 having
the cocoon-shaped cross-section needs rather complicated steps,
resulting in the increase of the cost. Incidentally, there is
another method for the formation of the through hole 46, in
which after the joint portion 45 of the band 5 is divided into
upper and lower parts (see the dotted line in Fig. 14) and half
holes for the through hole 46 are formed, both halves are
bonded together. However, the number of the
mechanical parts is increased and the number of the
manufacturing steps is increased, resulting in the degradation
in productivity and the increase of the entire cost for the
watch.
-
The present invention has been made in order to
overcome the above-noted problems, and has an object to provide
a joint structure for a watch and a watch using the joint
structure in which the number of mechanical parts is decreased,
the manufacture and assembly are simple and costs therefor are
low, furthermore, the attachment/detachment is easy, and there
is no fear that a joint pin would be fallen away in case of use
of the watch.
-
In order to attain these objects, according to the
present invention, there is provided a joint structure for a
watch in which a case joint portion for joint provided on a
case for the watch and a band joint portion for joint provided
on a band are laterally disposed adjacent to each other,
engagement holes in communication with each other in a lateral
direction are provided in both the joint portions,
respectively, and a joint pin for coupling the case for the
watch and the band with each other is inserted into each of the
engagement holes, the joint structure being characterized in
that a coiled spring is inserted into at least either one of
both the engagement holes, and the joint pin is inserted into
an inner diameter of the coiled spring so that the joint pin is
retained by the inner diameter portion of this coiled spring
and applied to both the engagement holes.
-
With such a structure, since the number of the
mechanical parts is small, the joint work may readily be
attained. In addition, the coiled spring may be machined with
ease so that the number of the manufacture steps is decreased
and the cost therefor may be reduced. Also, since the joint pin
is retained by utilizing the inner diameter portion of the
coiled spring, the resiliency of the coiled spring may be
utilized effectively, it is easy to couple the components with
each other, and in addition, it is possible to realize a
function to make it possible to remove the joint pin without
any strong force but the joint is not easily released. When
the overall inner diameter portion of the coiled spring is
utilized, each coil wraps the outer surface of the outer
diameter of the pin so that the total frictional force is
increased and there is no fear that the pin would be
accidentally fallen away. Furthermore, since the fixing force
for the pin is the frictional force or the retaining force
caused by the resiliency of the coiled spring, upon the
attachment/detachment work, it is possible to easily perform
the work without using a special tool or a large force. There
is no fear that the watch would be damaged or the pin would be
bent.
-
According to the present invention, there is provided
another joint structure for a watch, including a joint
structure for a band to be connected to a watch body in which
at least two joint members are connected, comprising an
engaging joint portion for joint provided on one of the joint
members and an engaged joint portion for joint provided in a
lateral direction adjacent to the engaging joint portion for
the one joint member to be disposed in a connection direction
adjacent to the other of the joint members, wherein engagement
holes in communication with each other in a lateral direction
are provided in both joint portions, a coiled spring is
inserted into at least either one of both the engagement holes,
and a joint pin is inserted into an inner diameter of this
coiled spring so that the joint pin is retained by the inner
diameter portion of this coiled spring and applied to both the
engagement holes.
-
With such a structure, when the joint members are
coupled with each other, since the number of the mechanical
parts is decreased, the weight of the overall band may be
reduced. Since the attachment/detachment work of the joint
portions may be simple, the work efficiency is enhanced and at
the same time the band may be finished with an aesthetic
design. Furthermore, since the coiled spring is used, the
number of the manufacture steps is decreased to reduce the
cost. Since the joint pin is retained by utilizing the inner
diameter portion of the coiled spring, the resiliency of the
coiled spring may be utilized effectively, it is easy to couple
the components with each other, and in addition, it is possible
to realize a function to make it possible to remove the joint
pin without any strong force but the joint is not easily
released.
-
According to another aspect of the invention, in
addition to the watch joint structure of the above-described
aspects, either one of the two joint portions is bifurcated
projections, any other of the two joint portions is a
projection to be inserted into the bifurcated projections, the
engagement hole is formed as a through hole in each of the
bifurcated projection and the projection, the coiled spring is
inserted into the engagement holes of the projections, and the
joint pin is disposed so as to be applied to the three through
holes.
-
With such a structure, it is unnecessary to provide a
gap in advance between the joint portions. Thus, there are no
restrictions over the design and at the same time, the unity of
design is enhanced, which is preferable for aesthetic design.
Also, the coiled spring is inserted in the middle of the
projections, it is possible to positively prevent the coiled
spring from being fallen away. Also, since the three through
holes have a diameter that is somewhat greater than that of the
pin and the joint portions may be thinned, it is possible to
enhance the aesthetic design.
-
According to another aspect of the invention, in
addition to the watch joint structure of the above-described
aspects, an inner diameter of a part of the coiled spring is
formed into a small diameter spring portion that is smaller in
diameter than the other portion, an outer diameter of a part of
the joint pin is formed into a small outer diameter portion
that is smaller in diameter than the other portion, and the
small diameter spring portion is fitted around the small outer
diameter portion to thereby retain the joint pin.
-
With such a structure, when the joint pin is passed
through the small diameter spring portion of the coiled spring,
since the small diameter spring portion is elastically deformed
and expanded, it is possible to insert the pin into the inner
diameter of the coiled spring by pushing the pin with a light
force. The portion that has been deformed by the resiliency of
the small diameter spring portion is restored back to the
original shape, when it is fitted with the small outer diameter
portion of the joint pin, it is possible to obtain a click
feeling to facilitate the confirmation of the assembly and the
small diameter spring portion has a retaining function to make
it possible to positively retain the pin.
-
The small diameter spring portion of the coiled
spring is fitted with the small outer diameter portion of the
joint pin to thereby retain the joint pin. Such a structure
further enhances the force for fixture of the pin. Also, when
the pin is pulled out, the pull-out is easy due to the
resiliency of the spring and there is almost no fear that the
force for removal would be varied. Also, since it is
unnecessary to use a special tool, the cost will not be
increased and there is no fear that the joint portions would be
damaged.
-
According to another aspect of the invention, in
addition to the watch joint structure of the above-described
aspects, an inner diameter of the coiled spring is somewhat
smaller than an outer diameter of the joint pin, and the joint
pin is retained between the coiled spring and the joint pin by
contact friction. In the case where the small diameter spring
portion is not provided in the middle of the coiled spring,
when the joint pin is inserted, it is preferable that the inner
diameter of the coiled spring is somewhat smaller than the
outer diameter of the pin. With such a structure, when the pin
that is larger in diameter than the inner diameter of the
coiled spring is inserted, the coiled spring is deformed and
expanded and the frictional force to be applied to the surface
of the pin is increased by the resiliency that forces the
spring back to the original shape after the elastic
deformation. Accordingly, the frictional force between the
coiled spring and the outer surface of the pin, i.e., the
fixing force for the joint pin is increased to avoid the
disadvantage that the pin would be fallen away accidentally.
-
According to still another aspect of the invention,
there is provided a watch comprising a watch body having a
watch case where a case joint portion for joint is provided and
a band having a band joint portion disposed adjacent to the
case joint portion, wherein engagement holes for communication
of the two joint portions in a side surface direction are
provided in the two joint portions, respectively, a joint pin
are passed through the engagement holes to thereby couple the
watch case and the band, wherein a coiled spring is inserted
into at least either one of both the engagement holes, and the
joint pin is inserted into an inner diameter of the coiled
spring so that the joint pin is retained by the inner diameter
portion of the coiled spring and applied to both the engagement
holes.
-
With such a structure, since the number of the
mechanical parts is small, the joint work may readily be
attained. In addition, the coiled spring may be machined with
ease so that the number of the manufacture steps is decreased
and the cost therefor may be reduced. Also, since the joint pin
is retained by utilizing the inner diameter portion of the
coiled spring, the resiliency of the coiled spring may be
utilized effectively, it is easy to couple the components with
each other, and in addition, it is possible to realize a
function to make it possible to remove the joint pin without
any strong force but the joint is not easily released.
Incidentally, when the overall inner diameter portion of the
coiled spring is utilized, each coil wraps the outer surface of
the outer diameter of the pin so that the total frictional
force is increased and there is no fear that the pin would be
accidentally fallen away. Furthermore, since the fixing force
for the pin is the frictional force or the retaining force
caused by the resiliency of the coiled spring, upon the
attachment/detachment work, it is possible to easily perform
the work without using a special tool or a large force. There
is no fear that the watch would be damaged or the pin would be
bent. For this reason, it is possible to provide the watch
which may readily be assembled and in addition repaired,
thereby making it possible to reduce the cost for the watch.
-
According to another aspect of the invention, in
addition to the watch of the above-described aspects, either
one of the two joint portions is bifurcated projections, any
other of the two joint portions is a projection to be inserted
into the bifurcated projections, the engagement hole is formed
as a through hole in each of the bifurcated projection and the
projection, the coiled spring is inserted into the engagement
holes of the projections, and the joint pin is disposed so as
to be applied to the three through holes.
-
With such a structure, it is unnecessary to provide
gap in advance between the joint portions. Thus, a watch which
has no restrictions over the design, having excellent aesthetic
design, can be obtained and at the same time, the unity of
design is enhanced, which is preferable for aesthetic design.
Also, the coiled spring is inserted in the middle of the
projections, it is possible to positively prevent the coiled
spring from being fallen away. Also, since the three through
holes have a diameter that is somewhat greater than that of the
pin and the joint portions may be thinned and light, it is
possible to enhance the aesthetic design.
-
According to another aspect of the invention, in
addition to the watch of the above-described aspects, an inner
diameter of a part of the coiled spring is formed into a small
diameter spring portion that is smaller in diameter than the
other portion, an outer diameter of a part of the joint pin is
formed into a small outer diameter portion that is smaller in
diameter than the other portion, and the small diameter spring
portion is fitted around the small outer diameter portion to
thereby retain the joint pin.
-
The invention may be carried into practice in various
ways and some embodiments will now be described by way of
example with reference to the accompanying drawings in
which:
- FIG. 1 is an exploded perspective view showing a
joint structure for a watch and the watch according to a first
embodiment of the present invention;
- FIG. 2 is a partially enlarged cross-sectional
view showing the state in which a pin of the joint structure
for the watch shown in Fig. 1 is inserted;
- FIG. 3 is a longitudinal sectional view showing
the structure of a coiled spring to be used in the watch joint
structure shown in Fig. 1;
- FIG. 4 is a transverse sectional view showing a
small spring portion of the coiled spring taken along the line
A-A of Fig. 3 and its periphery;
- FIG. 5 is a view showing another example of a
small diameter spring portion for the coiled spring to be used
in the watch joint structure shown in Fig. 1 and showing an
example having an oblong small diameter spring portion;
- FIG. 6 is an exploded perspective view showing a
joint structure for a watch according to a second embodiment of
the present invention;
- FIG. 7 is a partially enlarged cross-sectional
view showing the state in which a pin of the joint structure
for the watch shown in Fig. 6 is inserted;
- FIG. 8 is a view showing the structure of a
coiled spring to be used in the watch joint structure shown in
Fig. 6;
- FIG. 9 is a partially enlarged exploded
perspective view showing an example in which a watch joint
structure is used for the joint member of a watch band;
- FIG. 10 is a view showing an another
modification of the present invention and another example of
the joint structure between the watch case and the band;
- FIGs. 11A and 11B are views showing the
structure of a joint pin to be used in the joint structure for
the watch or the watch according to the present invention, Fig.
11A being a view showing another example of the joint pin
having a small outer diameter portion and Fig. 11B being a view
showing a joint pin having no small outer diameter portion;
- FIG. 12 is an exploded perspective view showing
an example of a conventional joint structure for a watch;
- FIG. 13 is a partially enlarged cross-sectional
view showing the state in which a joint pin is inserted in the
conventional watch joint structure shown in Fig. 12; and
- FIG. 14 is an exploded perspective view showing
another example of a conventional watch joint structure.
-
-
The present invention will now be described with
reference to the accompanying drawings.
-
Fig. 1 is an exploded perspective view showing a
joint structure for a watch and the watch according to a first
embodiment of the present invention. As shown in Fig. 1, a
projection 2 is formed as a case joint portion in a watch case
1. A single engagement hole 3 is formed to pass through the
projection 2 in a lateral direction. A band joint portion 4a
which is connected to the watch case 1 is provided in a band 4
of the watch. Bifurcated projections 5 and 5 are provided at a
tip end of the band joint portion 4a. The bifurcated
projections 5 and 5 have engagement holes 6 and 6 that pass
through in a lateral direction. The three engagement holes 6, 3
and 6 are arranged in a linear manner when the projection 2 and
the bifurcated projections 5 and 5 are engaged with each other,
and a joint pin 7 may be inserted to connect the case 1 and the
band 4 to each other.
-
As shown in Fig. 2, an inner diameter D3 of the
engagement hole 3 of the projection 2 of the watch case 1 is
formed to be larger than an inner diameter D6 of the engagement
holes 6 and 6 of the band joint portion 4a and a cylindrical
coiled spring 8 is inserted in the engagement hole 3 in
advance. An outer diameter D8 of the cylindrical coiled spring
8 (see Fig. 3) is provided to be smaller than the inner
diameter D3 so that the coiled spring 8 may be smoothly
inserted into the engagement hole 3. For instance, in the case
where the inner diameter D3 of the engagement hole 3 is 1.40
mm, the outer diameter D8 of the coiled spring 8 is 1.37 mm.
-
Also, in this embodiment, as shown in Figs. 1 and 2,
a small recess 9 that is smaller in diameter than the other
portion is formed in the middle of the joint pin 7 made of
stainless steel. On the other hand, a reduced diameter spring
portion 10 is also formed in the middle of the coiled spring 8.
-
As shown in Fig. 2, beveled portions 7a and 7a are
formed as tapers at both ends of the joint pin 7. Beveled
portions 7b and 7b are provided as tapers having the same shape
on both sides of the recess 9. The beveled portions 7a, 7a
function to facilitate the insertion of the pin 7 through the
coiled spring 8 through the small diameter spring portion 10 by
facilitating the expansion of the small diameter spring portion
10 as the pin 7 is inserted through. The beveled portions 7b
and 7b of the recess 9 work to disengage the small diameter
spring portion 10 of the coiled spring 8 with a force that is
large to some extent (i.e., the pull-out force or push force).
-
When the band 4 is assembled to the watch case 1, the
coil spring 8 is inserted into the engagement hole 3 and then
the three projections 5, 2 and 5 are located adjacent to each
other in a longitudinal direction. The engagement holes 6 and 6
of the bifurcated projections 5 and 5 of the band joint portion
4a are in alignment with the engagement hole 3 into which the
coiled spring 8 has been inserted. Then, the joint pin 7 is
inserted from one of the engagement holes 6, and inserted into
the inner diameter of the coiled spring 8. Furthermore, the
joint pin 7 is inserted into the other engagement hole 6. This
condition is shown in Fig. 2 and the case 1 and the band 4 are
coupled together.
-
When the joint pin 7 is inserted into one of the
engagement holes 6, its tip end is brought into abutment with
the small diameter spring portion 10. When the pin 7 is further
inserted against the abutment force, the small diameter spring
portion 10 is further advanced while being expanded by the
beveled portion 7a. Then, when the joint pin 7 is inserted into
the engagement holes 6, 3 and 6, the annular recess 9 of the
joint pin 7 and the small diameter spring portion 10 of the
coiled spring 8 are engaged with each other to thereby have a
click feeling to finish the joint work.
-
It is preferable that, in order to insert the joint
pin 7 into the engagement holes 6 and the coiled spring 8, the
outer diameter D7 of the joint pin 7 has a constant room or
idle space relative to the inner diameter D6 of the engagement
holes 6 and the inner diameter D8 of the coiled spring 8. In
one embodiment, the outer diameter D7 of the joint pin 7 is
1.00 mm, the inner diameter D8 of the coiled spring 8 is 1.05
mm, the inner diameter D6 of the engagement holes 6 is 1.10 mm,
and the inner diameter D3 of the hole 3 is 1.40 mm. The length
L8 of the coiled spring 8 is set substantially at he same
length as that of the projection 2 that serves as the case
joint portion.
-
In this embodiment, as mentioned above, the inner
diameter D6 of the engagement holes 6 and 6 of the band joint
portion 4a is 1.10 mm and the outer diameter D8 of the coiled
spring 8 is 1.37 mm. For this reason, an inner edge of each
engagement hole 6, 6 prevents the coiled spring 8 from moving
in a lateral direction while just abutting both ends of the
coiled spring 8. As a result, the coiled spring 8 is never
fallen away from the engagement hole 3 so far as the joint pin
7 is not pulled out.
-
In this embodiment, an inner diameter S of the small
diameter spring portion 10 of the coiled spring 8 is set at
0.95 mm. Also, a diameter d7 at a tip end of the tapered
portions of both ends of the joint pin 7 is somewhat smaller
than the inner diameter S. However, if the diameter D7 Ds
smaller than a distance S1 between the centers of the line
diameter, the insertion work is rather facilitated.
-
When the joint pin 7 is inserted into the coiled
spring 8 so that the small diameter spring portion 10 is passed
therethrough, the small diameter portion 10 is expanded by
resiliency of the coiled spring 8. In this case, when it is
fitted in the small outer diameter portion 9 of the joint pin 7
by the resilient force for restoration of the small diameter
spring portion 10 and the worker feels a click, the joint pin 7
is retained.
-
In the case 1 and band 4 thus coupled with each other
in such an engagement method, the number of the mechanical
parts is decreased, the cost therefor is reduced and the work
is enhanced. Also, it is possible to readily perform the
insertion attachment/detachment work of the coiled spring 8
with a stable force of 1 kg or less. The working efficiency is
enhanced. Also, since the machining of the respective
engagement holes 6, 3 and 6 may readily be performed and the
joint portions 5, 2 and 5 may be thinned, it is possible to
obtain the joint portion having excellent aesthetic design. In
the watch using such a joint structure, the small outer
diameter portion 9 of the joint pin 7 is inserted into the
small diameter spring portion 10 of the coiled spring 8 so that
there is no fear that the joint pin 7 would be fallen away in
case of use. Thus, it is possible to provide the watch that is
in safety and may be produced in low cost. Also, it is easy to
insert the joint pin 7 due to the provision of the beveled
potion 7a. It is easy to pull the joint pin 7 out due to the
provision of the beveled portions 7b and 7b.
-
In the embodiment, the coiled spring 8 is made of
resilient stainless steel material. As shown in Fig. 4, the
small diameter spring portion 10 is formed in a circular shape.
The inner diameter S of the small diameter spring portion 10 is
smaller than the inner diameter d8 of most ofDthe portion of
the coiled spring 8 by 0.1 mm, and the diameter is gradually
increased toward both ends so that the diameter becomes the
inner diameter D8 at a position apart from the small diameter
spring portion 10 by about one twelfth of the entire length L8.
-
As shown in Figs. 5A and 5B, the small diameter
spring portion 10 may be formed into an oblong small diameter
spring portion 10a. A short inner diameter S of the oblong
small diameter spring portion 10a is shorter than the inner
diameter D8 of the other portion of the coiled spring 8 and a
long inner diameter S2 is longer than the inner diameter Do. In
case of such a structure, when the joint pin 7 is inserted and
the small diameter spring portion 10a is passed, the insertion
is performed with the short inner diameter S being expanded,
and the short diameter portion thereof is fitted in the small
outer diameter portion 9 of the joint pin 7 to thereby retain
the joint pin 7.
-
A second embodiment of the present invention will now
be described with reference to Figs. 6 and 8. Incidentally, the
same reference numerals are used to indicate the like portions
or parts as those of the first embodiment.
-
In the second embodiment, a cylindrical joint pin 12
that has no central diameter reduced portion and a cylindrical
coiled spring 11 that has no small diameter portion are used.
When the joint work for the watch case 1 and the band 4 is
performed, in the same manner as in the first embodiment, the
coiled spring 11 is inserted into the engagement hole 3 in
advance, and the joint pin 12 is inserted while the engagement
holes 6 and 6 of the bifurcated projections 5 and 5 of the
joint portion 4a of the band 4 are in alignment with the
engagement hole 3 provided in the projection 2 of the watch
case 1.
-
In the embodiment, the inner diameter D3 of the
respective engagement holes 3, 6 and 6 is 1.40 mm, an inner
diameter D6 is 1.10 mm, an outer diameter D11 of the coiled
spring 11 is 1.30 mm, and an inner diameter D11 is in the range
of 0.98 to 0.99 mm. Thus, the coiled spring 11 is disposed
within the engagement hole 3 and clamped between both inner
edge portions of the engagement holes 6 and 6. The outer
diameter D12 of the joint pin 12 is greater than the inner
diameter D11 of the coiled spring 11 by 0.01 to 0.02 mm and is
1.00 mm.
-
With such a setup, when the joint pin 12 is to be
inserted into the inner diameter portion of the coiled spring
11, the coiled spring 11 is deformed and expanded due to the
resiliency. After the expansion and deformation, a fastening
force is applied to the surface of the joint pin 12 due to the
resiliency for restoration. Accordingly, a frictional force is
generated between the coiled spring 11 and the joint pin 12 so
that the joint pin 12 is fixed in place. Thus, there is no
fault that the joint pin 12 would be fallen away.
-
During the attachment/detachment work of the joint
portions 2 and 4a, the pull-out and insertion work of the joint
pin 12 may be performed with a force of 1 kg or less in a
stable manner and any special tool or a large force is not
necessary. The insertion and pull-out may readily be performed.
In addition, it is possible to perform the work without any
fear that the surface of the watch case 1 or the band 4 would
be damaged.
-
The foregoing two embodiments are preferred
embodiments of the present invention but the invention is not
necessarily limited to those. It is possible to make various
modifications and changes within the scope without departing
from the point of the invention. For example, as shown in Fig.
9, it is possible to apply the invention to a joint structure
of the watch band between a plurality of joint members 20 and
20 If the plurality of joint members 20 and 20 are arranged
adjacent to each other in a connection direction, it is
possible to provide a band.
-
In the joint member 20, one side in a longitudinal
direction is formed into bifurcated projections 22 and 22 that
serve as an engaged joint portion and the other side is formed
into a projection 21 that serves as an engaging joint portion.
The joint member 20 has the bifurcated projections 22 and 22
and the projection 21 at both ends in the same manner as in the
joint member 20. In the same manner as in the foregoing two
embodiments, a coiled spring 25 is inserted into engagement
holes 23 and 23 of the projections 21 and 21 The projection 21
is inserted in between the bifurcated projections 22 and 22 a
joint pin 26 is inserted into engagement holes 24 23 and 24 of
the two joint members 20 and 20 in a lateral direction.
-
The coiled spring 25 and the joint pin 26 used in the
band 4 have the same shape as that of the coiled spring 11 and
the joint pin 12 of the second embodiment but the combination
of the coiled spring 8 and the joint pin 7 of the first
embodiment may be applied thereto.
-
If such a joint structure is applied to the joint
portion of the band 4 of the watch, the attachment and pin
removal work are simple so that the work ability is enhanced
and at the same time the number of the mechanical parts is
decreased to realize the low cost. Also, since the
attachment/detachment is easy, it is possible to avoid the fear
that the band 4 is damaged during the assembling work. The
adjustment of the length of the watch band may readily be
attained in comparison with the conventional case.
-
As shown in Fig. 10, the joint pin 12 that has no
small diameter portion in the middle may be used in combination
with the coiled spring 8 that has the small diameter spring
portion 10 in the middle. The inner diameter of the small
diameter spring portion 10 of the coiled spring 8 is smaller
than the outer diameter of the joint pin 12 by about 0.01 to
0.03 mm. As a result, when the joint pin 12 is inserted into
the small diameter spring portion 10, the small diameter spring
portion 10 is expanded. The small diameter spring portion 10
fastens the joint pin 12 and exhibits a frictional force to the
joint pin 12 due to the resilient force for restoration of the
small diameter spring portion 10. For this reason, the joint
pin 12 is retained on the coiled spring 8. There is no fear
that the joint pin 12 would be fallen away.
-
As shown in Fig. 11, in order that the joint pins 7,
12, 26 may readily be inserted into the coiled springs 8, 11,
25 having the inner diameter smaller than the outer diameter
thereof, it is preferable that the beveled portions 7a, 7a and
14, 14 are formed at both ends of the joint pins 7, 12, 26.
However, it is possible to form the pin in the perpendicular
state without providing any beveled portions 7a, 7a and 14, 14
or to form much longer beveled portions.
-
In the pin 7 having the small outer diameter portion
9, as shown in Fig. 11A, a slow beveled portion 7c and a steep
beveled portion 7d that are different in slant angle may be
provided instead of the beveled portions 7b and 7b having the
same shape and connected to the outer diameter of the small
outer diameter portion 9. With such a structure, when the joint
pin 7 is inserted into the coiled spring 8 having the small
diameter spring portion 10, the insertion may be attained
smoothly. On the other hand, when the joint pin 7 is pull out,
by utilizing the slow beveled portion 7c, it is possible to
readily pull the joint pin 7 out without using any special tool
or large force.
-
In the above-described respective embodiments, the
small diameter spring portion 10 of the coiled spring 8 and the
joint pin 7 having the small outer diameter portion 9 are
provided at one position. However, it is possible to provide at
a plurality (two or three) of portions. It is possible to make
the coiled springs 8, 11, 25 of elastic material having a
resistance against water such as rubber or resin in addition to
the stainless steel. Also, the joint pins 7, 12, 26 may be made
of any other material having a sufficient mechanical strength
such as ceramics, engineering plastics or the like in addition
to the stainless steel.
-
With respect to the place where the coiled springs 8,
11, 25 are laid, the coiled springs are not inserted into the
engagement hole of the projection but coiled springs may be
inserted into the engagement holes of the bifurcated
projections one by one or may be inserted into all the
engagement holes. The length and the diameter of the joint pins
7, 12, 26 and the coiled springs 8, 11, 25 may be changed to be
longer or shorter, thinner or thicker depending upon a kind of
a mechanical part and work ability. Furthermore, not only the
connection is made so that the projection 2 is inserted between
the bifurcated projections 5 and 5, but also the bifurcated
projections are provided on the side of the case 1 and a single
projection may be provided on the side of the band 4.
Furthermore, the connection may be made by any combination
between a single projection and a single projection, between
bifurcated projections and bifurcated projections, between the
bifurcated projections and trifurcated projections or the like.
-
All of the engagement holes 3, 6, 23, 23 24 and 24
are through holes. However, in order to allow the insertion of
the joint pin only from one direction, the other end may be
clogged. Furthermore, in the embodiments, the connection
between the case body and the band of the wrist watch and the
connection between the respective joint members of the band
have been described. However, the present invention may be
applied to a decorative product such as a necklace or the like,
a practical product such as a chain or the like in addition to
the wrist watch.
-
As described above in detail, in the watch joint
structure according to the present invention, since the joint
pin is retained by the coiled spring, the number of the joint
members is decreased, the assembling work may be simplified,
the attachment/detachment work is simple, and there is no
disadvantage that the joint pin would be fallen away in case of
use of the watch. Furthermore, there is no fear that the joint
pin would be bent in case of use. Also, the machining of the
respective mechanical parts of the joint portions may be
simplified and the miniaturization thereof is easy.
Accordingly, there are no various limits to the joint portions.
The design of the joint portion is free. The design may be
enhanced.
-
In the watch according to the present invention,
since the above-described joint structure is used, in addition
to the above-described effect, the number of the manufacture
steps and the number of the machining steps for the mechanical
parts of the watch are decreased, it is possible to increase
the manufacture efficiency and to obtain the watch in low cost.
Also, since there are no various restrictions in design for the
joint portions, it is possible to provide an aesthetic watch
that is free from design restrictions. Since the work with a
large force is dispensed with, the risk is largely reduced in
which the watch body or case and the band portion or the like
are damaged. Furthermore, the number of the mechanical parts
for the joint portions is decreased and the miniaturization
thereof is possible. Accordingly, it is possible to reduce the
weight of the watch itself and at the same time, to enhance the
touch feeling.
-
Furthermore, in the band portion of the watch using
this joint structure, since the attachment and detachment of
the joint portion may readily be attained, it is possible to
simplify the adjustment of the length of the band and to
quickly perform the work such as repair or the like. Also, it
is possible to provide a variety of types for the band shape
and at the same time to provide a downsized and lightweight
band.