Seiko Cal.4006A
1960年代に販売されていた機械式アラーム時計
SEIKO ビジネス・ベル
Business Bell
自動巻 (Automatic)
直径 dm = 31.20 mm
高さ h = 7.15 mm
振動数 19,800 vph
石数 17/27Jewels
拘束角 Lift angle 58.5°
秒針停止機能 ？
曜日
日付
日付早修正機能付き（プッシュ)
アラーム
1/4 27J
2/4 27J
3/4 27J
1/3 17J
3/3 17J
1/2 17J
♦️Technical Document
1. Specifications
Casing diameter 31.20 mm
Height 7.15 mm
Vibrations per hour 19,800
Automatic winding with sweep second
Calendar (day and date)
Instant date setting device
Bell alarm device
＊＊
2. Structure of casing part
2-1. Glass
Glass with tension ring (Fig. 1 & 2)
2-2. Case back (Screw type)
A gasket mounted on the outside of the screwed part maintains a waterproof condition. (Fig. 1 & 2)
2-3. Securing the movement
The movement is secured by the casing spring which is located between the case back and the movement. (Fig. 2)
2-4. Crown
Ordinary waterproof type
2-5. Bell button
A bell button for setting the bell and date is attached at the 2 o'clock position.
This bell button is of the same waterproof construction as the crown of the recessed crown type. (Fig. 3)
2-6. Dial
Dial is especially shaped, provided with an edge to determine the positions of the dial and the alarm setting wheel.
(Fig. 1)
2-7. Alarm setting wheel
An alarm setting wheel is provided on the dial periphery. This feature is found only in the 4006A which excels both in
design and function. The alarm setting wheel is secured to the movement through an alarm setting wheel holder, and it interlocks with the alarm setting train and crown. (Fig. 2)
3. Automatic winding mechanism
3-1. Exploded view of automatic winding mechanism (Fig. 4)
3-2. Transmission of force in automatic winding mechanism (Fig. 5)
• An eccentric pin in a ball bearing performs circular motions by right and left rotations of the oscillating weight.
The pawl lever performs reciprocative motions due to circular movement of the eccentric pin, and the pawl lever rotates the transmission wheel constantly in one direction.
This motion is transmitted to the ratchet wheel from the transmission wheel; thus, the mainspring is wound.
Since a pawl lever is adopted, whose actions transmit right and left rotations of the oscillating weight in one direction
—magnifying the rotating force-and prevent reversal motion of the main-spring, this automatic winding mechanism is extremely simplified.
In addition to the simplified construc-tion, all automatic winding parts are set on the framework for automatic device; as a result, disassembling and reassembling are extremely easy.
4 Calendar and bell alarm mechanism
4-1. Exploded view of calendar and bell alarm mechanism (Fig. 6)
4-2. Mechanism of calendar device
(Fig. 7)
Hour wheel
Date dial
Day star with dial disk
Intermediate date
driving whee
↓
Date finger
Day driving wheel
Intermediate date wheel
(Day & date driving pin) Day & date driving wheel
4-3. Date setting (Fig. 8)
By depressing the bell button, the date corrector is actuated and the date dial
driven.
Due to one-side free mechanism of the date finger, date correction through the button can be achieved even in a condition when the date finger is forwarding the date dial.
4-4. Day setting
Day setting can be performed by alternating the hands between 9:30 P.M.
to 1:00 A.M. on the dial.
4-5. Setting mechanism
The setting mechanism consists of the crown (three-position changeover) and bell button (two-position changeover and push).
Turning the hands (Fig. 9)
When the crown is pulled out to the third position, the yoke is pushed by the setting lever, meshing the clutch wheel and setting wheel.
At the same time, the setting wheel lever complete is pushed by the pin on the setting lever through the setting wheel rocker so that the intermediate setting wheel and the intermediate minute wheel are engaged.
Therefore, by turning the crown hereon, force is transmitted in the sequence of clutch wheel→setting wheel→intermediate setting wheel-intermediate minute wheel→minute wheel→hour wheel • cannon pinion... thus turning the hands.
Winding the alarm mainspring
(Fig. 10, 11 & 12)
When the crown is under the first position, the clutch and the winding pinion are engaged with each other.
By turning the
crown, force is transmitted in the sequence of clutch wheel-winding pinion→crown wheel-intermediate winding wheel→alarm ratchet wheel...winding the alarm main-spring. (Fig. 10 & 11) If the bell button is pulled out, however, the yoke is pushed by the alarm setting lever; accordingly, under this condition the clutch wheel and winding pinion are disengaged, and the alarm mainspring is not wound. (Fig. 12) The intermediate wheel rocker for alarm serves as a click. When the spring is about to return (by force applied in the opposite direction indicated by the arrow mark), the alarm ratchet wheel and the alarm intermediate wheel are engaged with each other. This torque is transmitted
in the sequence of the alarm intermediate wheel→alarm wheel→alarm hammer. Since the alarm hammer is stopped by the alarm bolt yoke, the spring remains wound.
When winding the alarm mainspring, the intermediate wheel rocker spring for alarm will bend; consequently, the intermediate wheel and the alarm wheel are disengaged.
Bell time setting (Fig. 13)
When the crown is pulled out to the second position, the yoke is pushed by the setting lever so that the clutch wheel and the setting wheel are meshed with each other.
Under this condition, the setting wheel lever complete is held in a position shown in Fig. 13 by means of the setting lever spring, and the intermediate setting wheel is engaged with the intermediate unlocking wheel. Therefore, by turning the crown, torque is transmitted in the sequence of the clutch wheel→setting wheel → intermediate setting wheel-intermediate unlocking wheel..turning the unlocking
wheel. Subsequently, torque is further transmitted in the sequence of the unlocking wheel→alarm setting connection wheel→in-termediate alarm setting wheel... turning the alarm setting wheel. Under this condition, bell timing can be accurately set.
The alarm setting wheel, interlocking with the unlocking wheel, serves to indicate the bell ringing position on the dial. The spring attached to the setting wheel rocker functions to press the alarm setting wheel as shown in Fig. 14 when the crown is depressed on completion of setting the bell time, preventing the alarm setting wheel from moving through receiving mechanical shocks.
Bell setting (Fig. 15)
When the bell button is pulled to the second position, the alarm setting lever is actuated, separating the alarm bolt yoke from the hammer; thus the bell is prepared for ringing. When the preset bell time
arrives, the hammer is actuated and the bell rings. At this time, the alarm setting lever pushes the disengaging the
winding pinion and the clutch wheel from
each other. Therefore, the winding train wheel is reversed as far as the winding pinion. Until the bell ringing time arrives, the hammer is stopped by the disconnecting lever.
Ringing the bell (Fig. 16)
When the time indicated by the set mark is reached, the projection of the hour wheel is aligned with the unlocking wheel hole.
Under this condition, the hour wheel and disconnecting lever are both raised by the disconnecting lever spring, resulting in separation of the disconnecting lever from the hammer. Then the hammer beats the sounding spring continuously, sounding the bell until the force of the alarm mainspring is expended.
Stopping the bell (Fig. 17)
When the bell button is pushed to the first position, the hammer is held by the alarm bolt yoke, stopping the bell from ringing.
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