JP2532755Y2 - Zero return mechanism of analog clock - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a return mechanism for an analog timepiece in which an hour hand, a minute hand and a second hand return to a predetermined position independently when a predetermined time is set.

[0002]

2. Description of the Related Art With the increase in the functionality of analog watches, the hour and minute hands are independently operated by a motor that can be rotated forward and backward to switch the time of cities in each country, the current time and the alarm time. Thus, a timepiece having various functions such as automatic switching and display has been produced.

In this type of timepiece, sensors for detecting the positions of the hour hand, minute hand and second hand are separately provided in a timepiece control circuit such as a microcomputer in order to store the positions of the hour hand, minute hand and second hand. A position resetting mechanism for stopping the hour hand, minute hand and second hand at predetermined positions by position detection by a sensor is provided.At time setting, after the hour hand, minute hand and second hand are moved to predetermined positions by the resetting mechanism,
By driving the motor with a signal from the control circuit and counting the signal, the control circuit stores the position of the pointer.

[0004]

However, in the conventional analog timepiece described above, three sensors for detecting the positions of the hour hand, the minute hand, and the second hand at the time of the zero return are required for the zero return mechanism, which increases the cost and increases the cost. There was a problem that the movement became thick and the structure became complicated.

Accordingly, an object of the present invention is to provide an analog timepiece in which the time can be set by a simple operation, the movement is not thickened, and the structure is simplified.

[0006]

That is, the present invention has three wheels: a second hand wheel for driving a second hand, a minute hand wheel for driving a minute hand, and an hour hand wheel for driving an hour hand, which are arranged in parallel with each other.
An analog timepiece in which the second hand, minute hand and hour hand are operated independently by a motor capable of rotating forward and backward to display time, and the second hand, minute hand and hour hand are returned to predetermined return positions by a predetermined operation. In the zero-return mechanism, at least a part of the three wheels of the second hand wheel, the minute hand wheel, and the hour hand wheel are disposed so as to overlap at one place, and one sensor that emits light and detects reflected light is provided by the three hands. A car is provided toward the outermost car of the overlapping portion, and among the three cars, a through hole is provided on the optical axis of the sensor of the car closest to the sensor and the car in the middle.
The sensor is provided with a reflector formed on the optical axis of one of the cars farthest away from the sensor and having the same size as the through-hole, and the same as the through-hole on the surface of the intermediate car except the through-hole. A reflector is provided with a radius, and a control unit for controlling the rotation of the motor based on a detection signal from the sensor is provided.

[0007]

When a predetermined zero-return start operation is performed, the rotation of the vehicle closest to the sensor is controlled by the motor control by the control unit. When the reflected light is received, the passing hole is positioned in front of the sensor. , The zero return of the car closest to the sensor is performed. Next, the rotation of the intermediate vehicle is controlled, and when the reflected light is no longer received, the passing hole is located on the optical axis of the sensor, and the intermediate vehicle is returned to zero. Further, when the vehicle farthest from the sensor is controlled to rotate and the reflected light is received, the reflection portion is located on the optical axis of the sensor, and the vehicle farthest from the sensor is returned to zero.

[0008] Therefore, since the zero return operation can be performed by one sensor, the movement is not thickened as compared with the conventional case using two sensors, and the structure is simplified.
Cost can be reduced.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the drive structure (return-to-zero mechanism) of the analog timepiece according to the present embodiment drives the minute hand, the hour hand, and the second hand independently of each other. A second hand motor 5 is provided. In the figure, reference numeral 19 denotes a stator, 21 denotes a coil, and 23 denotes a rotor.

A fifth gear 7 is mounted on a drive shaft of the hour hand motor 1, and the fifth gear 7 is sequentially connected to an hour wheel 13 via a fourth gear 9 and a third gear 11. Then, the hour hand is driven by the hour wheel 13. In addition, the minute hand motor 3
The fifth gear 7 is axially mounted on the drive shaft, and the fifth gear 7 is sequentially connected to the minute hand wheel 15 via the fourth gear 9 and the third gear 11. Then, the minute hand is driven by the minute hand wheel 15. Similarly, a fifth gear 7 is mounted on a drive shaft of the second hand motor 5, and the fifth gear 7 is sequentially connected to a second hand wheel 17 via a fourth gear 9 and a third gear 11. Then, the second hand is driven by the second hand wheel 17.

The hour wheel 13, the minute wheel 15 and the second wheel 17
As shown in FIG. 2, the reflection type optical sensor 25 is disposed concentrically and parallel to each other from bottom to top, and above the top second hand wheel. Have been. The sensor 25 emits light and detects reflected light from a reflective plate described later.

3 (a), 3 (b) to 5 (a),
As shown in (b), the second hand wheel 17 is provided with a passage hole 27 through which the light emitted from the sensor passes in a state where the second hand wheel 17 is coaxially arranged and overlapped with each other. Is provided with a passage hole 29 which is slightly wider in the circumferential direction than the passage hole 27, and further, at a similar position of the hour wheel 13, a reflection portion 31 having the same size as the passage hole 29 is provided. Is provided.

Further, the minute hand wheel 15 is provided with a reflecting portion 33 having the same radius as that of the passing hole 29.
3 is formed to have the same width as the radial width of the passage hole 29.

Therefore, the second hand wheel 1 is provided below the sensor 25.
When the reflecting hole 33 of the minute hand wheel 15 is located below the passing hole 27 of the seventh wheel 7, the reflected light is detected by the sensor 25. A second hand wheel 17 is located below the sensor 25.
The passing hole 27 of the minute hand wheel 15 is located below the passing hole 27, and the passing hole 29 of the minute hand wheel 15 is located below the passing hole 27.
When the reflecting portion 31 of the hour wheel 13 is located below the passage hole 29 of the fifth sensor 5, the sensor 25 detects reflected light.

Each of the passage holes 27 and 29 and the reflecting portion 31 are located at the return position of the hour hand, minute hand and second hand (for example, at 12:00)
Are provided so as to overlap with each other.

Further, the sensor 25 comprises a photodiode and a phototransistor, and is connected to a microcomputer (control unit). The microcomputer rotates the hour hand motor 1, minute hand motor 3, and second hand motor 5 by the microcomputer. The control is performed.

Next, the return-to-zero control of the analog timepiece having the above configuration will be described with reference to the flowchart shown in FIG.

First, when a predetermined reset switch is operated, it is determined whether or not reflected light due to light emitted from the sensor 25 has been received (step S1). When the reflected light is received, the passing hole 27 of the second hand wheel 17 is provided in front of the sensor 25.
Then, the second hand wheel 17 is reversely rotated, for example, 90 ° by driving the motor 5 (S2). When the reflected light is not received, for example, since the state is as shown in FIGS.
Step (for example, 6 °) rotation (S3), it is determined whether reflected light has been received (S4). If no reflected light has been received, it is determined whether second hand wheel 17 has rotated one or more rotations. (S5).

If the second hand wheel 17 has not rotated one or more revolutions, the process returns to step S3, and steps S3 to S5 are repeated until the second hand wheel 17 has rotated one or more revolutions. If the reflected light is not received even if the second hand wheel 17 rotates one or more turns, the sensor 2
Assuming that there is a passage hole 29 of the minute hand wheel 15 before 5, the second hand wheel 17 is stopped (S 6), and the position of the passage hole 29 of the minute hand wheel 15 is shifted by rotating the minute hand wheel 15 by, for example, 90 ° (S 7).
It returns to step S3 and starts over.

When the reflected light is received in step S4, as shown in FIGS.
Assuming that there is a passage hole 27 of the second hand wheel 17 before 5, the second hand wheel 17 is stopped (S 8), and as shown in FIGS. 9A and 9B, the passage hole 27 of the second hand wheel 17 is detected. At the same time, it is detected that the reflecting portion 33 of the minute hand wheel 15 is located below the passage hole 27 of the second hand wheel 17. Next, the minute hand wheel 15 is rotated by one step in the forward rotation direction (S9), and it is determined whether reflected light is still received (S10). If reflected light is received, no reflected light is received. Steps S9 to S11 are repeated until the minute hand rotates once. In this case, if the reflected light is still received even if the minute hand wheel 15 makes one rotation, the minute hand wheel 15 is stopped (S12), the hour hand wheel 13 is rotated by 90 ° (S13), the process returns to step S9, and the process is repeated.

If no reflected light is received in step S10, it is assumed that the passing hole 29 of the minute hand wheel 15 is located below the passing hole 27 of the second hand wheel 17 as shown in FIGS. 10 (a) and 10 (b). The minute hand 15 is stopped (S14), and both the second hand and the minute hand return to the zero position, and the hour hand 13 is shown in FIGS. 11 (a) and 11 (b).
State. Next, the hour wheel 13 is rotated by one step (S15), and it is determined whether or not reflected light is received (S1).
6) If no reflected light is received, steps S15 and S16 are repeated until reflected light is received. If reflected light is received, as shown in FIGS. 12 (a) and 12 (b). In addition, the reflecting portion 31 of the hour wheel 13 is connected to both the passing holes 27 and 29.
, The hour wheel 13 is stopped (S1).
7) The second hand, minute hand, and hour hand return to zero, and the return-to-zero process ends.

As described above, in this embodiment, the second hand, minute hand and hour hand return to zero just by pressing the reset button, so that the time can be easily set. Further, since the zero-zero operation can be performed by one sensor, the movement does not become thicker than in the case where three sensors are used as in the related art, the structure is simplified, and the cost can be reduced. . still,
In the present embodiment, the through holes are provided in the second hand and the minute hand, and the reflecting portions are provided in the minute hand and the hour hand. However, the present invention is not limited to this, and the passing holes are provided in accordance with the arrangement positions of the second hand, the minute hand and the hour hand. Alternatively, a reflection unit may be provided.

[0023]

[Effect of the Invention] As described above, according to the present invention, 1
Since the two hands, the minute hand, and the hour hand can be returned to zero by the two sensors, the movement does not become thick, the structure is simplified, and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing a driving mechanism of a second hand, a minute hand, and an hour hand according to an embodiment of the present invention.

FIG. 2 is a front view showing a second hand, a minute hand and an hour hand.

FIG. 3 is a plan view and a longitudinal sectional view of a second hand wheel.

FIG. 4 is a plan view and a longitudinal sectional view of a minute hand wheel.

FIG. 5 is a plan view and a vertical sectional view of an hour wheel.

FIG. 6 is a flowchart showing a zero return control process.

FIG. 7 is a longitudinal sectional view and a plan view of a second hand wheel showing a zero-return operation.

FIG. 8 is a vertical sectional view and a plan view of a second hand wheel showing a zero-return operation.

FIG. 9 is a longitudinal sectional view and a plan view of a minute hand wheel showing a zero-return operation.

FIG. 10 is a longitudinal sectional view and a plan view of a minute hand wheel showing a zero-return operation.

FIG. 11 is a longitudinal sectional view and a plan view of an hour wheel showing a zero-return operation.

FIG. 12 is a longitudinal sectional view and a plan view of an hour wheel showing a zero-return operation.

[Explanation of symbols]

 1, 3, 5 motor 13 hour hand wheel 15 minute hand wheel 17 second hand wheel 25 Sensor 27, 29 Passage holes 31, 33 Reflector

Claims (2)

(57) [Scope of request for utility model registration] 1. A second hand wheel comprising a second hand wheel for driving a second hand, a minute hand wheel for driving a minute hand, and an hour hand wheel for driving an hour hand, which are disposed in parallel with each other, and wherein the second hand wheel is driven by a motor capable of rotating forward and reverse. And a minute hand and an hour wheel are operated independently to display the time, and a predetermined operation is performed to return the second hand, the minute hand and the hour hand to predetermined return positions. A part of the three cars, the minute hand wheel and the hour hand wheel, is arranged so as to overlap at one place, and one sensor that emits light and detects reflected light is provided on the outermost car of the portion where the three cars overlap. And a passing hole is provided on the optical axis of the sensor of the car closest to the sensor and the intermediate car among the three cars, and is provided on the optical axis of one car farthest from the sensor. Along with providing a reflecting portion formed in the same size as the passage hole An analog, comprising: a reflector provided on the surface of the intermediate vehicle excluding the passage hole with the same radius as the passage hole; and a control unit for controlling the rotation of the motor based on a detection signal from the sensor. Clock zeroing mechanism. 2. The analog timepiece according to claim 1, wherein the second hand wheel, the minute hand wheel, and the hour hand wheel are arranged sequentially and concentrically facing each other, and the sensor is provided in front of the second hand wheel. Zero zero mechanism.