Automatic watch

An automatic watch, a complete barrel 30 is disposed on the side opposite from the dial of a main plate 22, i.e. on the front side, and has the center of rotation thereof within a first domain 310 or a fourth domain 340 of the main plate 22. An escape wheel & pinion 50, a pallet fork 60 and a balance 70 have their center of rotation within a third domain 330 or a fourth domain 340, respectively. A setting lever 120 and a yoke 130 are disposed on the front side of the main plate 22 and have their center of oscillation within the second domain 320, respectively. A yoke holder 140 holds a part of the setting lever 120 and a part of the yoke 130, respectively.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates generally to an automatic watch in which a 
spring in a complete barrel is wound by an oscillating weight and more 
particularly to an automatic watch whose movement could have been 
miniaturized and thinned by disposing a front gear train mechanism and a 
change-over mechanism on the side opposite from a dial of a main plate. 
2. Description of the Prior Art 
A conventional automatic watch has had a main plate which constitutes a 
base of a movement and a change-over mechanism such as a setting lever and 
a yoke has been disposed on the dial side of the main plate. A calendar 
mechanism has been also disposed on the dial side of the main plate as 
necessary. 
Here, the movement means a mechanical body including a mechanical 
structural and operational parts of a watch. An automatic watch is 
composed of the mechanical body and casing parts. 
Further, a gear train mechanism, an escape speed governor and an automatic 
winder have been disposed on the side opposite from the dial of the main 
plate, i.e. on the front side. 
A member for holding the setting lever has been also arranged so as to 
press, i.e. urge, only the part of the setting lever around the center of 
oscillation by its elastic force. 
Further, no member for guiding incorporation of a clutch wheel has been 
provided. 
Accordingly, the prior art automatic watch has had the following problems: 
(1) Because the calendar mechanism is disposed on the dial side of the main 
plate, the change-over mechanism overlaps with the calendar mechanism, 
increasing the size of the movement or the thickness of the movement. 
(2) There has been a possibility that either one of the setting lever or 
the yoke runs onto the other at a contact section of the setting lever and 
the yoke when a winding stem is pressed in. 
(3) It has been hard to incorporate the clutch wheel. 
Further, because the clutch wheel inclines when the winding stem is pulled 
out to decompose the automatic watch, the winding stem could not be 
readily incorporated again. 
SUMMRY OF THE INVENTION 
Accordingly, it is an object of the present invention to solve the 
aforementioned prior art problems by providing: 
(1) a small and thin automatic watch; 
(2) an automatic watch having a structure in which the setting lever and 
the yoke are hardly disconnected at the contact section thereof; and 
(3) an automatic watch which allows the clutch wheel to be incorporated 
readily. 
In order to solve the aforementioned problems, an inventive automatic watch 
comprises a main plate; a center wheel & pinion which rotates centering 
almost on a center portion of the main plate as a center of rotation; a 
complete barrel having a spring; an escape speed governor mechanism; a 
winding stem and a clutch wheel; a change-over mechanism; a dial; and an 
oscillating weight for winding the spring via an automatic winding 
mechanism. 
When there are defined, on the main plate, a main plate reference vertical 
axis which passes through the center of rotation of the center wheel & 
pinion and is almost parallel with the center axis of the winding stem and 
a main plate reference horizontal axis which passes through the center of 
rotation of the center wheel & pinion and is vertical to the main plate 
reference vertical axis, there are provided, on the main plate, a first 
domain positioned at one side of the main plate reference vertical axis 
and at the side closer to the winding stem from the main plate reference 
horizontal axis, a second domain positioned at the other side of the main 
plate reference vertical axis and at the side closer to the winding stem 
from the main plate reference horizontal axis, a third domain positioned 
on the other side of the main plate reference vertical axis where the 
second domain is located and at the side farther from the winding stem 
from the main plate reference horizontal axis, and a fourth domain 
positioned at one side of the main plate reference vertical axis where the 
first domain is located and at the side farther from the winding stem from 
the main plate reference horizontal axis. 
The inventive automatic watch comprises the complete barrel disposed on the 
side opposite from the dial of the main plate and having the center of 
rotation within the first domain or the fourth domain; the escape wheel & 
pinion disposed on the side opposite from the dial of the main plate and 
having the center of rotation within the third domain or the fourth 
domain; the pallet fork disposed on the side opposite from the dial of the 
main plate and having the center of oscillation within the third domain or 
the fourth domain; the balance disposed on the side opposite from the dial 
of the main plate and having the center of rotation within the third 
domain or the fourth domain; the setting lever disposed on the side 
opposite from the dial of the main plate and having the center of 
oscillation within the second domain; the yoke disposed on the side 
opposite from the dial of the main plate and having the center of 
oscillation within the second domain; and a yoke holder for holding a part 
of the setting lever and a part of the yoke, respectively. 
The inventive automatic watch further comprises a second wheel & pinion 
which is operative to indicate seconds; and a third wheel & pinion for 
transmitting the rotation of the center wheel & pinion to the second wheel 
& pinion; and preferably the center of rotation of the third wheel & 
pinion is located within the second domain or the third domain. 
Further, in the inventive automatic watch, the complete barrel, the pallet 
fork, the escape wheel & pinion, the balance, the yoke and the setting 
lever are disposed in this order on the side opposite from the dial of the 
main plate clockwise or counter-clockwise around the center wheel & pinion 
on the basis of the main plate reference vertical axis. 
Then, in the inventive automatic watch, the center of rotation of the 
pallet fork and the center of rotation of the escape wheel & pinion are 
disposed at the position closer to the center of rotation of the center 
wheel & pinion rather than the center of rotation of the balance; a part 
of the winding stem and a part of the balance are positioned so as to be 
almost opposite each other with respect to the main plate reference 
horizontal axis; and a part of the complete barrel and a part of the yoke 
are positioned so as to be almost opposite each other with respect to the 
main plate reference vertical axis. 
Preferably, a part of the complete barrel and a part of the third wheel & 
pinion are disposed so as to be almost opposite each other with respect to 
the main plate reference vertical axis; and the center of rotation of the 
escape wheel & pinion and the center of rotation of the third wheel & 
pinion are positioned so as to be almost opposite each other with respect 
to the main plate reference horizontal axis. 
Preferably, the yoke holder-comprises a first holding part for urging a 
part the setting lever around the center of oscillation to the main plate 
and a second holding part for urging a part of the setting lever between 
the part around the center of oscillation and a part of the setting lever 
contacting with the yoke to the main plate. 
It is also preferable to have a clutch wheel incorporation guide member 
disposed adjacent to the clutch wheel on the side opposite from the dial.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
A mode for carrying out the invention will be explained below based on the 
drawings. 
(1) Structure of Front Gear Train, Escape Speed Governor and Change-Over 
Mechanism 
In FIGS. 1 and 2, an inventive automatic watch is provided with a main 
plate 22 which constitutes a base of a movement 20. While the outside 
shape of the main plate 22 is almost circular in this mode, it may be 
another shape such as a rectangular, polygonal or elliptic shape. 
According to the mode for carrying out the invention, a front gear train 
such as a complete barrel, a center wheel & pinion, a third wheel & pinion 
and a second wheel & pinion, an automatic winding mechanism such as an 
oscillating weight and a click lever, and a change-over mechanism such as 
a setting lever and a yoke are incorporated on the side opposite from the 
dial side, i.e. the front side, of the movement 20, respectively. 
"The opposite side from the dial side of the movement" will be referred to 
as "the front side of the movement" in general because when a casing 
structure having a back lid (not shown) is used, the front side of the 
movement 20 is normally seen when the back lid is removed. 
The inventive automatic watch may be also applied to a casing structure 
having no back lid as a matter of course, so that it is not intended to 
limit the present invention to the casing structure of the automatic watch 
having a back lid. 
A center wheel & pinion 24 is incorporated rotatably nearly at the center 
of the main plate 22. The center wheel & pinion 24 is incorporated between 
the main plate 22 and a center wheel bridge 26. A cannon pinion 28 is 
incorporated on the dial side of the main plate 22 so as to be able to 
slip at the peripheral portion adjacent to an edge closer to a hand 
attaching part of the center wheel & pinion 24. The cannon pinion 28 
rotates in a body with the center wheel & pinion 24. 
A complete barrel 30 is incorporated rotatably between the main plate 22 
and a barrel bridge 32. A gear of the complete barrel 30 engages with a 
second pinion of the center wheel & pinion 24. A third wheel & pinion 34 
is incorporated rotatably between the main plate 22 and the barrel bridge 
32. A second gear of the center wheel & pinion 24 engages with a third 
pinion. A second wheel & pinion 40 is incorporated rotatably between a 
center wheel bridge 26 and the barrel bridge 32. A third gear of the third 
wheel & pinion 34 engages with a fourth pinion of the second wheel & 
pinion 40. 
In FIGS. 1 through 3, an escape wheel & pinion 50 is rotatably incorporated 
between the main plate 22 and the barrel bridge 32. A fourth gear of the 
second wheel & pinion 40 engages with an escape pinion of the escape wheel 
& pinion 50. A pallet fork 60 is incorporated oscillably between the main 
plate 22 and a pallet bridge 62. The pallet fork 60 has two click stones 
63 and bayonets 64. An escape wheel of the escape wheel & pinion 50 
engages with the click stones 63. A balance 70 is incorporated rotatably 
between the main plate 22 and a balance bridge 72. The balance 70 has a 
hairspring 74 and a swing stone 76. The bayonet 64 engages with the swing 
stone 76. 
In FIGS. 2 and 5, a hour wheel 80 is incorporated rotatably in the main 
plate 22 on the side where a dial 82 is located. A minute wheel 90 is 
incorporated rotatably in the main plate 22 on the side where the dial 82 
is located. A minute wheel gear of the minute wheel 90 engages with the 
cannon pinion 28. A minute pinion of the minute wheel 90 engages with the 
hour wheel 80. 
In FIGS. 1 and 2, an oscillating weight 100 is incorporated rotatably to 
the barrel bridge 32. The oscillating weight 100 is incorporated to the 
barrel bridge 32 through an intermediary of a ball bearing (not shown). A 
first transmission wheel (not shown) is incorporated rotatably so as to 
engage with the pinion (not shown) of the oscillating weight 100. A click 
lever (not shown) is incorporated rotatably to an eccentric cam portion of 
the first transmission wheel. 
A second transmission wheel (not shown) is incorporated rotatably to the 
click lever so as to engage with the click portion (not shown). A ratchet 
gear of the second transmission wheel (not shown) engages with the click 
portion of the click lever. They are arranged such that the first 
transmission wheel (not shown) rotates based on the rotation of the 
oscillating weight 100 and the second transmission wheel rotates only in a 
predetermined direction based on the operation of the click lever. The 
spring is wound based on the rotation of the second transmission wheel 
(not shown). 
In FIGS. 1 through 7, there are defined, on the main plate 22, a main plate 
reference vertical axis 112 which passes through the center of rotation 
300 of the center wheel & pinion 24 and is almost parallel with the center 
axis of the winding stem 110 and a main plate reference horizontal axis 
114 which passes through the center of rotation 300 of the center wheel & 
pinion 24 and is vertical to the main plate reference vertical axis 112. 
There is provided, on the main plate 22, a first domain 310 positioned at 
one side of the main plate reference vertical axis 112 and at the side 
closer to the winding stem 110 from the main plate reference horizontal 
axis 114. There is provided, on the main plate 22, a second domain 320 
positioned at the other side of the main plate reference vertical axis 112 
and at the side closer to the winding stem 110 from the main plate 
reference horizontal axis 114. There is provided, on the main plate 22, a 
third domain 330 positioned on the other side of the main plate reference 
vertical axis 112 where the second domain 320 is located and at the side 
farther from the winding stem 110 from the main plate reference horizontal 
axis 114. There is provided, on the main plate 22, a fourth domain 340 
positioned at the above-mentioned one side of the main plate reference 
vertical axis 112 where the first domain 310 is located and at the side 
farther from the winding stem 110 from the main plate reference horizontal 
axis 114. 
It is noted that although the first domain 310 and the fourth domain 340 
are located on the right side of the main plate reference vertical axis 
112 in FIG. 7, those domains may be defined so as to be located on the 
left side of the main plate reference vertical axis 112. Naturally, the 
second domain 320 and the third domain 330 should be defined so as to be 
located on the right side of the main plate reference vertical axis 112 in 
such a case. 
In FIGS. 1 through 7, the center of rotation of the complete barrel 30 is 
located within the first domain 310. Such arrangement allows the spring 
having a large torque and is capable of operating for a long duration to 
be disposed effectively on the front side of the movement. 
The center of rotation of the complete barrel 30 may be disposed also 
within the fourth domain 340. 
The center of rotation of the escape wheel & pinion 50 is located within 
the third domain 330. The center of oscillation of the pallet fork 60 is 
located within the third domain 330. The center of rotation of the balance 
70 is located within the third domain 330. Such arrangement allows the 
large complete barrel to be used. Such arrangement also allows the large 
balance having an excellent time accuracy and a large moment of inertia to 
be disposed effectively on the front side of the movement. 
The center of rotation of the balance 70 may be disposed also within the 
fourth domain 340. 
The center of oscillation of the pallet fork 60 and the center of rotation 
of the balance 70 may be disposed also within the fourth domain 340. 
The center of rotation of the escape wheel & pinion 50, the center of 
oscillation of the pallet fork 60 and the center of rotation of the 
balance 70 may be disposed also within the fourth domain 340. Such 
arrangement allows the large third wheel & pinion to be disposed 
effectively on the front side of the movement. 
The center of oscillation 124 of the setting lever 120 is located within 
the second domain 320. The center of oscillation of the yoke 130 is 
located within the second domain 320. The setting lever 120 and the yoke 
130 are incorporated on the front side of the main plate 22. The yoke 
holder 140 presses parts of the setting lever 120 and the yoke 130, 
respectively, against the main plate 22. 
The yoke holder 140 is made of an elastically deformable material and is 
preferable to be made of stainless steel for example. The yoke 130 is made 
of an elastically deformable material and is preferable to be made of 
stainless steel for example. 
A spring portion 132 of the yoke 130 is located within the second domain 
320 and the third domain 330. Such arrangement allows the long spring to 
be disposed effectively on the front side of the movement. The spring part 
132 of the yoke 130 may be disposed only within the second domain 320. The 
shape of the yoke spring part 132 may be either straight, in bow or in 
U-shape. 
An angle part 142 of the yoke holder 140 engages with a positioning pin 122 
of the setting lever 120, thus positioning the setting lever 120 and 
setting a change-over weight of the winding stem 110. The angle part 142 
of the yoke holder 140 is arranged so that the winding stem 110 may be 
pulled out to a first stage and a second stage in the inventive automatic 
watch. A guide valley section 138 of the yoke 130 is pressed against the 
side face of the edge of the setting lever 120 by force of the spring part 
132 of the yoke 130. 
The center of rotation of the second wheel & pinion 40 which operates to 
indicate seconds is the same with the center of rotation 300 of the center 
wheel & pinion 24. That is, the embodiment of the present invention is a 
three-center-hand watch. The center of rotation of the second wheel & 
pinion 40 may be disposed at the different position from the center of 
rotation 300 of the center wheel & pinion 24. 
The third wheel & pinion 34 transmits the rotation of the center wheel & 
pinion 24 to the second wheel & pinion 40. The center of rotation of the 
third wheel & pinion 34 is located within the second domain 320. Such 
arrangement allows the large third wheel & pinion 34 to be disposed 
effectively on the front side of the movement. 
The center of rotation of the third wheel & pinion 34 may be disposed 
within the third domain 330. 
Here, a number of gear trains is not limited to those described above and 
one or more transmission wheels may be added. 
It is noted that although it is preferable to dispose each part described 
above in the arrangement as shown in FIG. 1, it is possible to dispose 
them so as to be arranged mirror-symmetrically from the arrangement shown 
in FIG. 1 with respect to the main plate reference vertical axis 112. 
For example, it is possible to arrange such that the center of rotation of 
the complete barrel 30 is located within the second domain 320, the center 
of rotation of the escape wheel & pinion 50 is located within the fourth 
domain 340, the center of oscillation of the pallet fork 60 is located 
within the fourth domain 340 and the center of rotation of the balance 70 
is located within the fourth domain 340. Then, it is also possible to 
arrange such that the center of oscillation 124 of the setting lever 120 
is located within the first domain 310 and the center of oscillation 136 
of the yoke 130 is located within the first domain 310. Such arrangement 
also allows the small and thin automatic watch to be realized similarly to 
the arrangement shown in FIG. 1. 
Further, in the inventive automatic watch, the complete barrel 30, the 
pallet fork 60, the escape wheel & pinion 50, the balance 70, the setting 
lever 120 and the yoke 130 are disposed in this order on the front side of 
the main plate 22 clockwise around the center wheel & pinion 24 on the 
basis of the main plate reference vertical axis 112 as shown in FIG. 1. 
Then, the center of rotation of the pallet fork 60 and the center of 
rotation of the escape wheel & pinion 50 are disposed at the position 
closer to the center of rotation 300 of the center wheel & pinion 24 
rather than the center of rotation of the balance 70. 
In the inventive automatic watch, the complete barrel 30, the pallet fork 
60, the escape wheel & pinion 50, the balance 70, the setting lever 120 
and the yoke 130 may be also disposed in this order on the front side of 
the main plate 22 counter-clockwise around the center wheel & pinion 24 on 
the basis of the main plate reference vertical axis 112 so that they are 
arranged mirror-symmetrically to the arrangement shown in FIG. 1. Then, 
the center of rotation of the pallet fork 60 and the center of rotation of 
the escape wheel & pinion 50 are disposed at the position closer to the 
center of rotation 300 of the center wheel & pinion 24 rather than the 
center of rotation of the balance 70 also in this arrangement. 
A part of the winding stem 110 and a part of the balance 70 are positioned 
so as to be almost opposite each other with respect to the main plate 
reference horizontal axis 114. A part of the complete barrel 30 and a part 
of the yoke 130 are positioned so as to be almost opposite each other with 
respect to the main plate reference vertical axis 112. A part of the 
complete barrel 30 and a part of the third wheel 34 are positioned so as 
to be almost opposite each other with respect to the main plate reference 
vertical axis 112. The center of rotation of the escape wheel & pinion 50 
and the center of rotation of the third wheel & pinion 34 are positioned 
so as to be almost opposite each other with respect to the main plate 
reference horizontal axis 114. 
Next, an operation of the inventive automatic watch will be explained with 
reference to FIGS. 1 through 3. 
The complete barrel 30 is rotated by force of the spring (not shown). The 
center wheel & pinion 24 is rotated as the complete barrel 30 rotates. The 
third wheel & pinion 34 is rotated as the center wheel & pinion 24 
rotates. The second wheel & pinion 40 is rotated as the third wheel & 
pinion 34 rotates. The cannon pinion 28 is also rotated as the center 
wheel & pinion 24 rotates. The minute wheel 90 is rotated as the cannon 
pinion 28 rotates. The hour wheel 80 is rotated as the minute wheel 90 
rotates. The rotational speed of each of the gear train is controlled by 
the operation of the balance 70, the pallet fork 60 and the escape wheel & 
pinion 50. As a result, the second wheel & pinion 40 rotates once in one 
minute. The cannon pinion 28 and the center wheel & pinion 24 rotate once 
in one hour. The hour wheel 80 rotates once in 12 hours. 
"Second" is indicated by a second hand (not shown) attached to the second 
wheel & pinion 40. "Minute" is indicated by a minute hand (not shown) 
attached to the cannon pinion 28. "Hour" is indicated by a hour hand (not 
shown) attached to the hour wheel 80. That is, the second wheel & pinion 
40, the cannon pinion 28, the center wheel & pinion 24 and the hour wheel 
80 compose indicating wheels for indicating time information. The time is 
read by a scale or the like on the dial 82. 
Next, winding of the spring by the automatic winder will be explained. 
When one swings his/her arm while bearing the automatic watch, the click 
lever operates like the eccentric cam on the basis of the rotation of the 
oscillating weight 100 and winds the spring by the rotation of an 
automatic winding transmission wheel (not shown) or the like having a 
ratchet gear. 
(2) Structure of Yoke Holder 
In FIG. 4, the yoke holder 140 is provided with a first holding part 144 
for urging a part of the setting lever 120 around the center of 
oscillation 124 to the main plate. The yoke holder 140 is also provided 
with a second holding part 146 for urging a part of the setting lever 120 
around the center of oscillation 124 and a part of the setting lever 120 
between it and the contact section 126 with the yoke 130 to the main 
plate. 
Force of the yoke holder 140 for holding the setting lever 120 is 
determined so as to have enough strength so that the engagement of the 
setting lever 120 with the yoke 130 will not come off when the winding 
stem 110 is pressed further from the zero stage. This force may be found 
by calculation or by experiment. Preferably, such holding force of the 
yoke holder 140 is about 150 gram. 
Such holding structure by means of the yoke holder 140 keeps the 
possibility that the engagement of the setting lever 120 with the yoke 130 
comes off to the minimum. 
Next, an operation of the change-over mechanism of the invention will be 
explained with reference to FIGS. 4 and 5. 
When one bears the automatic watch around arm, the winding stem 110 is 
normally on the zero stage. When one tries to correct the calendar, he/she 
pulls out the winding stem 110 to put on the first stage. At this time, 
the setting lever 120 is rotated. Then, the yoke 130 rotates by the spring 
force of the yoke and engages a gear B 162b of the clutch wheel 162 with a 
calendar corrector 170. When the winding stem 110 is rotated in this 
state, the clutch wheel 162 rotates, correcting a date indicator 172 or a 
day indicator 174 by the rotation of the calendar corrector 170. 
Next, when one tries to correct time, he/she pulls out the winding stem 110 
further to the second stage. At this time, the setting lever 120 rotates 
further. The yoke 130 rotates in the direction opposite from the 
above-mentioned rotation due to the spring force of the yoke and engages a 
gear A 162a of the clutch wheel 162 with the minute wheel 90. When the 
winding stem 110 is rotated in this state, the clutch wheel 162 rotates 
and the cannon pinion 28 and the hour wheel 80 rotate as the minute wheel 
90 rotates, thus correcting the indication of time. 
(3) Structure of Clutch Wheel Guide Member 
In FIG. 4, a clutch wheel incorporation guide member 160 is fixed of the 
barrel bridge 32 on the side where the winding stem 110 is located. The 
clutch wheel incorporation guide member 160 may be made of a metal such as 
brass or of plastic. 
The clutch wheel incorporation guide member 160 may be also formed in a 
body with the barrel bridge 32. It is preferable to form the clutch wheel 
incorporation guide section by way of cut work or plastic work when the 
barrel bridge 32 is made of a metal. It is preferable to form the clutch 
wheel incorporation guide section in a body with the barrel bridge 32 by 
injection molding or the like when the barrel bridge 32 is made of 
plastic. 
The surface of the clutch wheel incorporation guide member 160 on the side 
where the dial 82 is located is disposed adjoining with the clutch wheel 
162 so as to have a small gap 168 therebetween. The surface of the clutch 
wheel incorporation guide member 160 on the side where the dial 82 is 
located is formed into a dimension and shape which will not hamper the 
operation of the yoke 130. By arranging as such, the clutch wheel 162 
rides on the surface of the clutch wheel incorporation guide member 160 
when the winding stem 110 is pulled out while facing up the dial 82 for 
example to decompose the automatic watch. Accordingly, there is less 
possibility that the inclination of the clutch wheel 162 will make it 
difficult to assemble the automatic watch. 
Because the automatic watch is arranged as described above according to the 
present invention, the following effects are brought about: 
(1) The small and thin automatic watch may be realized; 
(2) The small automatic watch may be realized because the gear train 
mechanism, the escape speed governor and the change-over mechanism are 
disposed without wasting any space; 
(3) The clutch wheel may be readily assembled; and 
(4) The setting lever and the yoke are hardly disconnected at their contact 
section.