JP2009264885A - Electronic timepiece - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic timepiece having a position detecting means for reducing the current consumption, by shortening the operating time of the position detecting means, when the position of a gear is detected. <P>SOLUTION: This electronic timepiece includes a scoop wheel 275, rotated by an hour/minute hand motor 26; a 24-hour intermediate wheel 281 to which the rotation is transferred and that has a rotation speed slower than that of the scoop wheel 275; an hour/minute-hand optical sensor for detecting a detection hole 275A of the scoop wheel 275; and a 24-hour hand optical sensor for detecting a detection hole 281A of the 24-hour intermediate wheel 281. The hour/minute;hand optical sensor is set so as to detect the detection hole 275A, when the scoop wheel 275 further rotates by a predetermined angle, after the detection hole 281A has been detected by the 24-hour hand optical sensor. Therefore, the 24-hour-hand optical sensor is operated each several steps to detect the detection hole 281A, and then the hour/minute-hand optical sensor is operated for each step to detect the detection hole 275A, thereby the detection frequency is reduced and the current consumption can be reduced. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic timepiece and, for example, relates to an electronic timepiece having a position detection function of a hand or the like as represented by an analog radio wave correction timepiece that drives the hand or the like.

  Conventionally, in analog radio-controlled timepieces that drive hands, etc., if there is a mistake in driving the hands, etc. due to the impact of the needle jump or impact of an external magnetic field, the internal hand position counter and the actual position of the hands will be misaligned. Even if the time code is received, it may not be displayed correctly. Therefore, it is necessary to detect the position of the pointer or the like in order to check whether the position of the pointer or the like matches the value of the needle position counter. Such pointers for position detection include not only the usual hour, minute, and second hands, but also, for example, a 24-hour hand that displays 24 hours by one rotation linked to the hour hand via a gear, The date wheel or the like as a display is also targeted.

Conventionally, as a pointer position detection means in this type of radio-controlled timepiece, there is known a device that uses a light sensor including a light emitting element and a light receiving element, which is intended for each hour, minute, and second hands (for example, patents). Reference 1).
In these pointer position detection means, members such as gears that move in conjunction with the rotation of the pointer are arranged between the light emitting element and the light receiving element of the optical sensor, and these members detect light at a specific position. A detection hole is provided to pass through. When the detection light output from the light emitting element passes through the detection hole and the light receiving element receives light, it is detected that the pointer is at a specific position.

JP 2006-153659 A

  However, in the pointer position detecting means described in Patent Document 1, the optical sensor is operated every time the step motor is driven while the pointer is rotated from an arbitrary rotation position to a rotation position where the detection light passes through the detection hole. This is necessary, and this increases the number of times the photosensor is activated, which shortens the battery life. On the other hand, there has been a strong demand for minimizing the power consumed by the optical sensor when detecting the pointer position.

  An object of the present invention is to detect a position of a gear that drives a pointer or the like, a position that can reduce the current consumption by shortening the operation time of the position detecting means, and can detect the position of the gear with high accuracy. An electronic timepiece having detection means is provided.

  The electronic timepiece of the present invention includes a motor, a first gear rotated by the motor, a second gear to which the rotation of the first gear is transmitted, and the rotation speed with respect to the motor is slower than the first gear. First position detecting means for detecting that the first gear is at a predetermined first reference position; second position detecting means for detecting that the second gear is at a predetermined second reference position; An electronic timepiece comprising: a first position detecting means; and a detection control means for controlling the operation of the second position detecting means. The first position detecting means is configured such that the second gear is driven by the second position detecting means. When the first gear is further rotated by a predetermined angle after it is detected that it is at the second reference position, the detection control is set to detect that the first gear is at the first reference position. The means is the motor In a first gear position detection mode for detecting that the first gear has moved to the first reference position by driving, the second position detecting means is operated to move the second gear to the second reference position. After detecting that the second gear is in the second reference position, the first position detecting means is operated to detect that the first gear is in the first reference position. It is set as follows.

Here, the first reference position is set at a position of a predetermined rotation angle during one rotation of the first gear. A range of a certain rotation angle may be set at the predetermined angle position, and if the first gear is within the predetermined angle range, it may be detected as the first reference position. Similarly, for the second reference position, the second gear may be set within a predetermined angle range.
For example, when position detection is performed by step-driving the first gear with a step motor, the first position detection means is usually activated at every step, rather than the first position detection means being activated every few steps. However, the rotational position of the first gear can be detected with high accuracy.
However, since the operation of the first position detection unit is repeated for each step of the motor, the number of operations of the first position detection unit increases, which causes an increase in current consumption.
In contrast, in the present invention, the first gear and the second gear are arranged such that the first gear reaches the first reference position when the second gear first reaches the second reference position and further rotates by a predetermined angle. Is provided. Therefore, first, the second position detecting means is operated every several steps to detect the rotational position of the second gear, and when it is detected that the second gear has reached the second reference position, the first position detecting means is Each position detecting means can be operated so as to detect the rotational position of the first gear by operating every step. Here, since the rotation speed of the second gear relative to the motor is slower than that of the first gear, it is sufficient to detect the second gear every several steps.

For example, if the second gear is set at half the rotational speed of the first gear, the second gear is rotated every half turn in response to the first gear reaching the first reference position every rotation. Two detected portions may be provided in the second gear so as to reach the second reference position. And what is necessary is just to make it the detected part of either one of a 2nd gear detected in the position in front of the predetermined angle which a 1st gear reaches a 1st reference position.
In this way, the second gear is first detected every several steps, and then the first gear needs to be detected every step by a predetermined angle of rotation. The number of operation times of the position detecting means can be reduced as compared with the case of detecting each step. In addition, the position of the first gear can be detected with high accuracy by detection for each step as in the prior art.
Therefore, when detecting the position of the pointer or the like, the detection time can be shortened, the current consumption can be reduced, and the position can be reliably detected.

  The electronic timepiece of the present invention further comprises a rotation control means for controlling the motor, wherein the rotation control means indicates the rotational speed of the motor until the second gear reaches the second reference position, and the first gear It is preferable to control at a higher speed than the rotation speed of the motor until the first reference position is reached.

  According to this configuration, until the second gear reaches the second reference position, the second position detector detects the second gear at the second reference position after the position detection is started by fast-forwarding the motor. The time required for the process can be shortened.

  In the electronic timepiece of the invention, the first gear has a first detected portion detected by the first position detecting means, and the second gear is a second detected by the second position detecting means. A first detection unit and a second detection unit, wherein the second gear reaches the second reference position before the first gear reaches the first reference position. Is preferably set.

  According to this configuration, each gear is provided with a detected portion such as a hole or a step, and the rotation position detected by each position detecting means is set as the reference position of each gear. A detection system that detects whether each gear has reached each reference position can be easily configured.

  In the electronic timepiece according to the aspect of the invention, the second detected portion and the second position detecting unit may be configured such that at least the first gear reaches the first reference position after the second gear reaches the second reference position. In the meantime, it is preferable that the second detected portion is formed so as to be detectable by the second position detecting means.

Here, after the second gear reaches the second reference position and the second detected portion is out of the detectable range of the second position detecting means while further rotating by a predetermined angle, the first gear is Only the first position detection means detects that the first reference position has been reached.
On the other hand, in the present invention, when the first gear reaches the first reference position, both the first position detecting means and the second position detecting means detect the respective detected portions, respectively. The erroneous detection that occurs when the first gear at the first reference position is detected only by the position detection means is less likely to occur, and it is possible to more accurately detect that the first gear has reached the first reference position.

  In the electronic timepiece according to the aspect of the invention, the second position detecting unit is operated every time the second gear rotates by a predetermined angle, and the second detected portion is continuously at least twice by the second position detecting unit. It is preferably formed so as to be detectable.

  In this configuration, for example, when the second position detecting unit is operated every several steps of the motor, the second detected portion is formed to be continuously detectable at least twice by the second position detecting unit. As a result, even if the second position detection means cannot detect the second detected portion for the first time due to the influence of component variation, backlash, etc., the second detected position is detected after the second detection. Since there is an opportunity to detect the part, the possibility of erroneous detection of the second detected part is reduced, and the part can be detected more reliably.

  In the electronic timepiece according to the aspect of the invention, the first detected portion is a first through hole that penetrates the first gear, and the first position detection unit emits detection light to the first through hole. And a first light receiving means for receiving the detection light passing through the first through hole, and the second detected portion is a second through hole that passes through the second gear. And the second position detecting means includes a second light emitting means for emitting a detection light to the second through hole, and a second light receiving means for receiving the detection light passing through the second through hole. It is preferable that

  According to this structure, since each position detection means is comprised with the non-contact-type optical sensor, durability becomes favorable compared with a contact-type sensor. Moreover, since each detected part is a through-hole, the timing which detects the reference position of each gear can be easily set only by appropriately setting the dimension and shape of the through-hole.

  In the electronic timepiece of the present invention, the hour hand connected to the first gear and the second gear rotating at a reduction ratio of 1: 2 with respect to the first gear are displayed, and 24 hours are indicated by one rotation. And a 24-hour hand.

In this configuration, for example, first, the second reference position of the 24-hour hand is detected by the second position detection means at a position that is a predetermined angle before the midnight position. Thereafter, when the hour hand reaches the 12 o'clock position by rotating it by a predetermined angle, the second position detecting means may detect the first reference position of the hour hand. At this time, for example, detection is performed every several steps until the second reference position of the 24-hour hand is detected, and then detection is performed for each step until the hour hand reaches the 12 o'clock position. The number of operations of the means can be reduced. Further, AM / PM cannot be distinguished only by detecting the first reference position of the hour hand, but first, the second reference position of the 24-hour hand at a position that is a predetermined angle before the midnight position. AM / PM can be accurately distinguished by detecting the first reference position of the hour hand after detecting.
Therefore, when the position of the 24-hour hand located at the midnight position is detected, the detection time can be shortened, current consumption can be reduced, and position detection can be performed with high accuracy.

  As described above, according to the electronic timepiece of the present invention, when detecting the position of the gear that drives the hands or the like, the operating time of the position detecting means can be shortened to reduce current consumption, and with high accuracy. There is an effect that the position of the gear can be detected.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view of an electronic timepiece 1 according to an embodiment of the present invention. FIG. 2 is a diagram showing the internal structure of the electronic timepiece 1 with the back cover removed, and is a plane mainly showing the positional relationship between the motors 21, 26, 31 and the train wheels 22, 27, 28. The figure is shown. FIG. 3 shows a view of the internal structure of the electronic timepiece 1 with the dial removed, and a plan view mainly showing the positional relationship between the date wheel 30 and the 24-hour hand wheel train 28 is shown. .

1, FIG. 2, and FIG. 3, the electronic timepiece 1 is a radio wave correction watch with a hand position detection function that receives a standard radio wave as an external signal on which time information is superimposed and corrects the display time. In addition to the 12-hour display based on the normal hour, minute, and second pointers, a 24-hour display and a plurality of date display functions are provided.
The electronic timepiece 1 includes a pointer 2 (FIG. 1) for displaying the time for 12 hours, a pointer 9 (FIG. 1) for displaying the time for 24 hours, and a pointer driving means 20 for driving these hands 2 and 9 (FIG. 2). ). Further, a date wheel 30 (FIG. 3) as a calendar display mechanism for displaying the date (calendar) and a calendar motor 31 for driving the date wheel 30 are provided. Furthermore, a power storage unit 41 (FIG. 2) that stores a battery 40 that is a driving source of the pointer driving unit 20 and the calendar motor 31, an external operation unit 5 that can be operated by a user from the outside, and the above-described pointer. Drive means 20, date wheel 30, calendar motor 31, and main plate 10 that supports and fixes the power storage unit 41. An antenna (not shown) that receives standard radio waves is also supported and fixed on the ground plane 10. The base plate 10 is formed in a substantially circular planar shape, and each component of the electronic timepiece 1 is disposed on the base plate 10.
2, the upward direction is the 6 o'clock direction of the electronic timepiece 1, the downward direction is the 12 o'clock direction, the right direction is the 3 o'clock direction, and the left direction is the 9 o'clock direction. In FIG. The hour direction, downward direction is 6 o'clock direction, right direction is 3 o'clock direction, and left direction is 9 o'clock direction.

The pointer 2 (FIG. 1) has a second hand 2A, a minute hand 2B, and an hour hand 2C, and is provided so as to be coaxially rotatable about the approximate center of the main plate 10 (FIG. 2). The second hand 2A, the minute hand 2B, and the hour hand 2C are provided on the time display side, and indicate the time of 12-hour display by pointing the characters for 12-hour display on the dial plate 3 and the like.
Further, the pointer 9 (FIG. 1) has a 24-hour hand 9A, and is rotatably provided on an axis independent of the pointer 2 at 3 o'clock side from the center of the main plate 10 (FIG. 3). The 24-hour hand 9A displays a 24-hour display time by pointing a 24-hour display character on the dial plate 3 and the like.

FIG. 4 shows a diagram in which the dial 3 is removed from the time display side of the pointer driving means 20 (FIG. 2). The hands of the second hand 2A, the minute hand 2B, and the hour hand 2C shown in FIG. 1 are provided to be rotatable around an axis P in FIG. In FIG. 4, the upward direction is the 12 o'clock direction, the downward direction is the 6 o'clock direction, the right direction is the 3 o'clock direction, and the left direction is the 9 o'clock direction.
In FIG. 1 or FIG. 4, the pointer driving means 20 includes a second hand motor 21 for driving the second hand 2A, and an hour / minute hand motor 26 for driving the hour hand 2C, the minute hand 2B, and the 24-hour hand 9A. Between the second hand 2A and the second hand motor 21, a second hand wheel train 22 for transmitting the driving force from the second hand motor 21 to the second hand 2A is provided. On the other hand, an hour / minute hand train 27 for transmitting the driving force from the hour / minute hand motor 26 to the hour hand 2C and the minute hand 2B is provided between the hour hand 2C / minute hand 2B and the hour / minute hand motor 26. A 24-hour hand wheel train 28 for transmitting the driving force from the hour / minute hand motor 26 to the 24-hour hand 9A from the hour hand 2C to the 9-hour hand 9A is provided.

As shown in FIG. 4, the second hand motor 21 is formed of a stepping motor, and is disposed at a position approximately 8 o'clock from the center of the electronic timepiece 1.
The second hand train 22 includes a second intermediate wheel 221 that meshes with a rotor pinion 211 </ b> A formed integrally with the rotor 211 of the second hand motor 21, and a second wheel 222 (fourth wheel) that meshes with the second intermediate wheel 221. ing. A second hand 2A (FIG. 1) is fixed to the second wheel 222. The rotor 211 makes a half rotation with one pulse. This rotational movement is transmitted in the order of the rotor pinion 211A, the second intermediate wheel 221, and the second wheel 222 while being decelerated at an appropriate reduction ratio, and the second hand 2A rotates at a predetermined speed of one pulse per second. The rotational motion of the rotor 211 may be transmitted to the second hand 2A while being accelerated at an appropriate speed increase ratio.

  The second intermediate wheel 221 is engaged with a second detection wheel 223 for detecting the 12 o'clock position of the second hand 2A. In the second intermediate wheel 221 and the second detection wheel 223, detection holes 221A and 223A are formed in areas overlapping each other, and the phase of the second intermediate wheel 221 and the second detection wheel 223 is the position at which the second hand 2A is at the 12 o'clock position. The positions of the detection holes 221A and 223A are set to coincide with each other. That is, the 12 o'clock position is the reference position of the second hand 2A. Here, since the second detection wheel 223 has the same diameter as the second wheel 222, the positions of the detection holes 221A and 223A coincide with each other once a minute. A reference position of the second hand 2A is detected by a transmission type second hand light sensor (not shown) provided at a position where the detection holes 221A and 223A coincide.

  The hour / minute hand motor 26 which is the motor of the present invention is formed of a stepping motor, like the second hand motor 21. Specifically, the hour / minute hand motor 26 includes a rotor 261 having a rotor magnet 261 </ b> B, a stator 262 that rotatably holds the rotor 261, and a coil 263 that contacts the stator 262. The hour / minute hand motor 26 is disposed in the direction of approximately 3 o'clock of the electronic timepiece 1, and the rotor 261 is disposed at the center side of the main plate 10 and the coil 263 is disposed at the outer peripheral side of the main plate 10. In the present embodiment, as shown in FIG. 4, the hour / minute hand motor 26 and a 24-hour wheel 282 to be described later are arranged so as to overlap in a plane.

The hour / minute hand train 27 includes a fifth wheel 271 meshed with a rotor pinion 261 A formed integrally with the rotor 261, a third wheel 272 meshed with the fifth wheel 271, and a second wheel 272 meshed with the third wheel 272. A date wheel 273, a date wheel 274 meshing with the pinion 2731 of the second wheel 273, and an hour wheel 275 meshing with the pinion 2741 of the date wheel 274 are provided. The second wheel 273 and the hour wheel 275 are arranged coaxially with the second wheel 222, and the minute hand 2 </ b> B is fixed to the second wheel 273.
The hour hand 2C is fixed to the hour wheel 275 which is the first gear of the present invention.
Here, when a motor pulse is supplied to the coil 263 at a cycle of 5 seconds, a magnetic path is formed in the stator 262 by electromagnetic induction, and the rotor 261 is rotated halfway by one pulse. This rotational motion is transmitted while being decelerated at an appropriate reduction ratio in the order of the rotor kana 261A, the fifth wheel 271, the third wheel 272, and the second wheel 273, and the speed at which the second wheel 273 and the minute hand 2B make one round in one hour. To rotate. The rotational movement of the center wheel & pinion 273 is transmitted while being decelerated at an appropriate reduction ratio in the order of the minute wheel 274 and the hour wheel 275 in order, and rotates at a speed at which the hour wheel 275 and the hour hand 2C make one round in 12 hours. It comes to move.

The 24-hour hand train 28 includes a 24-hour intermediate wheel 281 that meshes with the pinion 2751 of the hour wheel 275 formed integrally with the hour wheel 275 and a 24-hour wheel 282 that meshes with the 24-hour intermediate wheel 281. Prepare.
The 24-hour intermediate wheel 281 that is the second gear of the present invention is disposed in the approximately 1 o'clock direction of the electronic timepiece 1. Further, the 24-hour wheel 282 is arranged in the approximately 3 o'clock direction of the electronic timepiece 1, and the 24-hour hand 9A is fixed to the 24-hour wheel 282. Since the 24-hour intermediate wheel 281 is interposed between the hour wheel 275 and the 24-hour wheel 282, the hour hand 2C and the 24-hour hand 9A have the same rotation direction. The rotational movement of the hour wheel 275 is transmitted while being decelerated at an appropriate reduction ratio in the order of the 24-hour intermediate wheel 281 and the 24-hour wheel 282, and the 24-hour wheel 282 and the 24-hour hand 9A rotate at a speed that makes a round in 24 hours. . Thus, the 24-hour intermediate wheel 281 has a lower rotational speed than the hour wheel 275 with respect to the hour / minute hand motor 26.
The reduction ratio of the 24-hour intermediate wheel 281 with respect to the hour wheel 275 is set to 1: 2. The 24-hour wheel 282 has the same diameter as the 24-hour intermediate wheel 281. The 24-hour wheel 282 and the 24-hour intermediate wheel 281 are driven at the same rotational speed.

  5 and 6 are side sectional views of the pointer driving means 20, and FIG. 5 is an hour / minute hand optical sensor 6 (first optical sensor) which is the pointer driving means 20 and the first position detecting means of the present invention. FIG. 6 shows the positional relationship between the pointer driving means 20 and the 24-hour hand light sensor 7 (second optical sensor) which is the second position detecting means of the present invention.

As shown in FIGS. 4 and 5, the second wheel 222, the fifth wheel 271, the third wheel 272, the second wheel 273, and the hour wheel 275 have detection holes 222A, 271A, 272A, and 273A in areas overlapping each other. , 275A are formed.
Here, the detection hole 275A provided in the hour wheel 275 constitutes a first through hole which is the first detected portion of the present invention.
When the second hand 2A, the minute hand 2B, and the hour hand 2C are arranged at the 12 o'clock position, the positions of these detection holes 222A, 271A, 272A, 273A, and 275A are set to coincide with each other. That is, the reference position of the second hand 2A, the minute hand 2B, and the hour hand 2C is the 12 o'clock position, which is the first reference position of the present invention.
In FIG. 5, a transmission type hour / minute hand light sensor 6 is provided at a position where the detection holes 222A, 271A, 272A, 273A, 275A coincide. The hour / minute hand light sensor 6 includes a first light emitting element 61 (first light emitting means) and a first light receiving element 62 (first light receiving means). The first light emitting element 61 and the first light receiving element. 62 are provided on both sides in the thickness direction of the second wheel 222, the fifth wheel 271, the third wheel 272, the second wheel 273, and the hour wheel 275, and are disposed to face each other with these interposed therebetween. When the second wheel 222, fifth wheel 271, third wheel 272, second wheel 273, and hour wheel 275 rotate and the detection holes 222A, 271A, 272A, 273A, 275A coincide with each other, Since the detection light from one light emitting element 61 passes through the detection holes 222A, 271A, 272A, 273A, 275A and is received by the first light receiving element 62, the second hand 2A, the minute hand 2B and the hour hand 2C are all at the 12 o'clock position. That is, it is detected that the state is the first reference position.
In the present embodiment, the first light emitting element 61 is mounted on the circuit block 61A disposed between the ground plane 10 and the solar panel 4, and the first light receiving element 62 is disposed on the back cover side from the ground plane 10. Although mounted on the circuit block 62 </ b> A, five wheels 222, 271, 272, 273, 275 are arranged between the first light emitting element 61 and the first light receiving element 62.

As shown in FIGS. 4 and 6, the 24-hour intermediate wheel 281 is formed with a detection hole 281A. This detection hole 281A constitutes a second through hole which is the second detected portion of the present invention.
The detection hole 281A has the 24-hour intermediate wheel 281 at the second wheel 222, the fifth wheel 271 and the third wheel 272 regardless of the position of the 24-hour hand 9A from 23:20 to 24:00 (midnight). The second wheel 273, the minute wheel 274, the hour wheel 275, and the 24-hour wheel 282 are provided in areas that do not overlap. Further, the detection hole 281A has an inner diameter dimension that allows the detection light of the 24-hour hand light sensor 7 to pass through the detection hole 281A regardless of the position of the 24-hour hand 9A from 23:20 to 24:00. ing. In the present embodiment, the detection hole 281A is a circular hole, but may be an elliptical hole or a long hole. Thus, the state in which the 24-hour intermediate wheel 281 is in the position from 23:20 to 24:00 is set as the state in which the 24-hour intermediate wheel 281 of the present invention is in the second reference position.

A transmission type 24-hour hand light sensor 7 similar to that provided in the hour / minute hand light sensor 6 is provided at the position of the detection hole 281A. The 24-hour hand light sensor 7 includes a second light emitting element 71 (second light emitting means) and a second light receiving element 72 (second light receiving means), and these second light emitting element 71 and second light receiving element. 72 are provided on both sides of the 24-hour intermediate wheel 281 in the thickness direction, and are arranged to face each other with these interposed therebetween.
Here, when the 24-hour intermediate wheel 281 rotates and the detection hole 281A moves to the position of the 24-hour hand light sensor 7, the detection light from the second light emitting element 71 of the 24-hour hand light sensor 7 passes through the detection hole 281A. Then, the light is received by the second light receiving element 72. Accordingly, the hour / minute hand light sensor 6 described above has been detected after the 24-hour hand light sensor 7 detects that the 24-hour hand 9A (24-hour intermediate wheel 281) has reached the second reference position at a position after 23:20. When the hour wheel 275 further rotates and the hour hand 2C reaches the 24 o'clock position, it is set to detect that the hour wheel 275 is at the first reference position.
In the present embodiment, the second light emitting element 71 is mounted on the circuit block 71 </ b> A disposed between the ground plane 10 and the solar panel 4, and the second light receiving element 72 is disposed on the back cover side from the ground plane 10. It is mounted on the circuit block 72A.

The base plate 10 is also provided with a first light transmitting hole 10A (FIG. 5) so as not to obstruct the light transmission of the hour / minute hand light sensor 6, and the second light so as not to obstruct the light transmission of the 24-hour hand light sensor 7. Of course, the transparent hole 10B (FIG. 6) is provided.
The second hand light sensor for detecting that the second hand 2A is at the reference position by using the second intermediate wheel 221 described above, the hour / minute hand light sensor 6 for detecting that the minute hand 2B and the hour hand 2C are at the first reference position, and the 24-hour hand. The 24-hour hand light sensor 7 that detects that 9A is at the second reference position is not limited to one that uses a transmissive optical sensor, and may be one that uses a reflective optical sensor, for example. For example, the present invention is not limited to detecting that the rotational position of the 24-hour intermediate wheel 281 is at the second reference position, but a magnetic pattern is formed on the circumference of the 24-hour intermediate wheel 281 and this magnetic pattern is read to read 24. The position of the hour intermediate wheel 281 may be detected.

Since the first reference position of the hour hand 2C rotates in a 12-hour cycle, the detection position 275A is provided in the hour wheel 275 that rotates in a 12-hour cycle, so that the reference position of the hour hand 2C is set to 12 in a display area of 360 degrees. It can be specified in one place at the hour position. Therefore, it is understood from the detection by the hour / minute hand light sensor 6 that the hour hand 2C is either midnight or midnight.
On the other hand, the second reference position of the 24-hour hand 9A is set to a position between 23:20 and 24:00:00, and rotates at a cycle of approximately 24 hours. Therefore, if the detection hole 275A of the hour wheel 275 and the detection hole 281A of the 24-hour intermediate wheel 281 are detected simultaneously by the hour / minute hand light sensor 6 and the 24-hour hand light sensor 7, the 24-hour hand 9A is at the position of midnight. Thus, AM / PM of the hour hand 2C can be distinguished.

FIG. 7 is a block diagram showing the configuration of the pointer position detecting means.
As shown in FIG. 7, the pointer position detecting means includes an hour / minute hand light sensor 6 for detecting the positions of the minute hand 2B and the hour hand 2C, and a 24-hour hand light sensor 7 for detecting the position of the 24-hour hand 9A.
The detection control means 81 controls the operation of the hour / minute hand light sensor 6 and the 24 hour hand light sensor 7, and the rotation control means 82 controls step driving of the hour / minute hand motor 26. These detection control means 81 and rotation control means 82 are provided in circuit blocks 62A and 72A (FIGS. 5 and 6) on the back cover side.
The detection control means 81 controls the hour / minute hand light sensor 6 to operate once for every one-step drive of the hour / minute hand motor 26, and the 24-hour hand light sensor 7 has one for every several steps of the hour / minute hand motor 26. It is controlled to operate once, specifically, every rotation angle of 20 minutes of the 24-hour hand 9A.

  The rotation control means 82 controls the hour / minute hand motor 26 to be driven at a normal speed step by step in conjunction with the position detection by the hour / minute hand light sensor 6 and the 24 hour hand light sensor 7, and the hour / minute hand motor 26 for several steps. It is configured to be able to execute at least two types of drive control, that is, continuous drive and fast-drive control. Specifically, when the position of the 24-hour hand 9A is detected, until the 24-hour hand light sensor 7 detects the detection hole 281A, the hour-minute hand motor 26 is driven to fast-forward for several steps, and the 24-hour hand light sensor 7 After the detection hole 281A is detected and until the hour / minute hand light sensor 6 detects the detection hole 275A, the hour / minute hand motor drive control means drives the hour / minute hand motor 26 step by step at a normal speed. . Note that the drive frequency of the fast-forward drive is made larger than the drive frequency of the normal speed. For example, in the case of the normal speed, the drive frequency of the hour / minute hand motor 26 is set to 25 Hz, and in the case of the fast-forward drive, The drive frequency of the hour / minute hand motor 26 is set to 42 Hz.

  The date wheel 30 shown in FIG. 3 is provided on the time display side from the main plate 10. A disk-shaped dial 3 (FIG. 1) is provided above the date wheel 30 (on the front side of the page in FIG. 3), and the date is displayed on a part of the outer periphery of the dial 3. A window portion 3A (FIG. 1) is provided, and a part of the date wheel 30 is visible as a date from the window portion 3A. The dial plate 3 is made of a light-transmitting material such as glass or plastic, and a solar panel 4 is disposed between the dial plate 3 and the base plate 10 as power generation means for generating power by incident light. ing.

The date wheel 30 is formed in a ring shape, and an internal gear 32 is formed on the inner peripheral surface of the date wheel 30. On the surface of the date dial 30 on the dial plate 3 side, characters “1” to “31” representing the date are displayed by printing or the like.
Similar to the second hand motor 21 and the hour / minute hand motor 26, the calendar motor 31 is formed of a stepping motor and is disposed in the approximately 1 o'clock direction of the electronic timepiece 1.
Between the date wheel 30 and the calendar motor 31, a calendar wheel train 33 for transmitting the driving force from the calendar motor 31 to the date wheel 30 is provided. The calendar wheel train 33 includes a date indicator driving wheel 333, and the date indicator driving wheel 333 is meshed with the internal gear 32 of the date indicator 30. The rotation of the calendar motor 31 is transmitted to the date indicator driving wheel 333 via the calendar wheel train 33, the date indicator 30 is rotated by the rotation of the date indicator driving wheel 333, and the displayed date is changed. The date indicator 30, the calendar motor 31, and the calendar wheel train 33 constitute a calendar display means.

  A battery 40 is stored in the power storage unit 41. The battery 40 is a secondary battery, and the electromotive force generated in the solar panel 4 is charged in the battery 40. The power storage unit 41 is disposed in the approximately 1 o'clock direction of the electronic timepiece 1 and is disposed on the outer peripheral side of the main plate 10.

When the time is corrected in such an electronic timepiece 1, the hand positions of the hands 2 and 9 are detected as follows. Here, a procedure for detecting that the 24-hour hand 9A has reached the 24-hour position will be described.
FIG. 8 is a flowchart showing the position detection process of the 24-hour hand 9A.
First, the rotation control means 82 drives the hour / minute hand motor 26 to be fast-forwarded for several steps (step 1, hereinafter, step is abbreviated as “S”). Then, the rotation control means 82 stops the hour / minute hand motor 26, and when the hour / minute hand motor 26 stops, the detection control means 81 operates the 24-hour hand light sensor 7 (S2). Specifically, the rotation control unit 82 drives the hour / minute hand motor 26 to fast-forward for 20 minutes at a driving frequency of 42 Hz, and then stops the hour / minute hand motor 26. Then, the detection control means 81 detects the 24-hour hand light sensor 7 only once. Next, it is determined whether or not the 24-hour hand light sensor 7 has detected the detection hole 281A of the 24-hour intermediate wheel 281 (S3). Until the detection hole 281A is detected, the fast-forward drive (S1) for 20 minutes and the 24-hour hand light are detected. The detection (S2) of the sensor 7 is repeatedly executed.
Here, after the detection hole 281A of the 24-hour intermediate wheel 281 reaches the position of 23:20, it is detected that the 24-hour intermediate wheel 281 is in the second reference position at the next detection. Even if the first detection fails, the detection hole 281A is formed so that it can be detected twice consecutively by the 24-hour hand light sensor 7, so that the second detection is made while the detection hole 281A moves to the 24 o'clock position. If the detection is successful in either of the two detections, it can be detected that the 24-hour intermediate wheel 281 is at the second reference position. As described above, the detection hole 281A is provided so as to be detectable within the range of the rotation angle of 40 minutes of the 24-hour intermediate wheel 281. Therefore, while the detection hole 281A passes the position of the 24-hour hand light sensor 7, The opportunity for the detection light of the hour hand light sensor 7 to pass through the detection hole 281A can be secured at least twice. As a result, the detection hole 281A can be reliably detected before the 24-hour intermediate wheel 281 reaches the 24-hour position.

When the 24-hour hand light sensor 7 detects the detection hole 281A, the detection control means 81 stops the 24-hour hand light sensor 7, and the rotation control means 82 drives the hour / minute hand motor 26 by one step at a driving frequency of 25 Hz (S4). ). Then, the rotation control means 82 stops the hour / minute hand motor 26, and when the hour / minute hand motor 26 stops, the detection control means 81 operates the hour / minute hand light sensor 6 only once (S5). Next, it is determined whether the hour / minute hand light sensor 6 has detected the detection hole 275A of the hour wheel 275 (S6), and one step of driving (S4) and the hour / minute hand light sensor 6 are detected until the detection hole 275A is detected. The detection (S5) is repeatedly executed.
Thereby, the position detection of the hour wheel 275 is performed with higher accuracy than the position detection of the 24-hour intermediate wheel 281. When the hour / minute hand light sensor 6 detects the hour wheel 275, the optical sensor control means stops the hour / minute hand light sensor 6, and the position detection of the 24-hour hand 9A at the 24 o'clock position is completed (S7).

  The time correction operation method is not particularly limited. For example, when the external operation means 5 such as a winding stem is operated, the time correction mode is set, and the position detection mode ( Switching to the first gear position detection mode) may be performed to detect the position of the 24-hour hand 9A.

[Effects of this embodiment]
According to this embodiment, the following effects can be achieved.
(1) When the 24-hour hand 9A is displayed for 24 hours by the method of decelerating the rotation of the hour wheel 275 and transmitting it to the 24-hour wheel 282, a cylinder that rotates for 12 hours by one rotation as in the prior art. Even if the detection hole 275A is provided in the vehicle 275 and it can be detected that the hour hand 2C has reached the 12 o'clock position, it cannot be determined whether the 24-hour hand 9A is at the 12 o'clock position or the 24 o'clock position. There was a problem that could not be determined. On the other hand, a detection hole 281A is provided in the 24-hour intermediate wheel 281 that rotates for 24 hours by one rotation, and the reference position of the 24-hour hand 9A is set at one position of the 24-hour position in the 360-degree display area. By specifying, AM / PM can be determined.

(2) Current consumption when performing the position detection of the 24-hour hand 9A can be reduced as compared with the conventional position detection. In order to explain this effect, as a comparative example, a case where the detection hole 281A of the 24-hour intermediate wheel 281 is provided so as to overlap the detection hole 275A of the hour wheel 275 similarly to the conventional position detection of the hour / minute hand will be described. In the method of detecting the position of the 24-hour hand 9A according to this comparative example, the detection of the hour / minute hand light sensor 6 must be executed every step while the 24-hour intermediate wheel 281 is rotated at most once, and the position of the hour hand 2C is detected. In this case, twice the detection time is required. Further, since the 24-hour intermediate wheel 281 is arranged so as to overlap with the fifth wheel 271, the train wheel becomes thick.
On the other hand, in this embodiment, a 24-hour hand light sensor 7 different from the hour / minute hand light sensor 6 is provided in the 24-hour intermediate wheel 281, and is first rotated 20 minutes by fast-forward drive, so that the 24-hour intermediate wheel 281 detection holes 281A are detected every 20 minutes of rotation. Then, after the 24-hour hand light sensor 7 detects the detection hole 281A, the hour / minute hand light sensor 6 detects the detection hole 275A of the hour wheel 275 every one step drive.
By such a method, in the case of fast-forward driving, it is 1.68 times faster than normal one-step driving, and as described above, the detection time required for rotating the 24-hour hand 9A one time at maximum is twice as long as the conventional method. However, it can be increased by about 1.2 times. For example, in the conventional method, it takes 6.9 minutes to take 11.52 minutes, which is twice 5.76. Here, when the detection hole 281A of the 24-hour intermediate wheel 281 is detected and then the detection hole 275A of the hour wheel 275 is detected until the rotation hole for three hours is driven, the detection hole 281A is detected. Since it takes a maximum of 2.3 minutes to detect the detection hole 275A after that, if this amount is added as a detection time, it will be 9.2 minutes. It can be shortened by 3 minutes. Furthermore, since the 24-hour intermediate wheel 281 is detected for every 20 minutes of rotation angle and the detection hole 281A is detected, the hour wheel 275 only needs to be detected for every rotation by a predetermined angle. Therefore, the number of times of operation of the hour / minute hand light sensor 6 and the 24-hour hand light sensor 7 can be reduced as compared with the case where the 24-hour intermediate wheel 281 is detected step by step. Further, the position of the hour wheel 275 can be detected with high accuracy by detection for each step as in the conventional case.
Therefore, when detecting the position of the 24-hour hand 9A, the detection time can be shortened, the current consumption can be reduced, and the position can be reliably detected.

(3) Since the detection range of the 24-hour hand light sensor 7 is set for the detection hole 281A of the 24-hour intermediate wheel 281 for a maximum of 40 minutes, it is reliably detected in consideration of component variations and backlash. The hole 281A can be detected.

(4) By providing a detection hole 281A in the 24-hour intermediate wheel 281 and setting the rotational position detected by the 24-hour hand light sensor 7 to the second reference position of the 24-hour intermediate wheel 281, A detection system that detects whether or not the 24-hour intermediate wheel 281 has reached the second reference position can be easily configured.

(5) When the hour wheel 275 reaches the first reference position, both the hour / minute hand light sensor 6 and the 24-hour hand light sensor 7 can detect the detection holes 275A and 281A, respectively. An erroneous detection that occurs when the hour wheel 275 at the first reference position is detected is less likely to occur, and it is possible to more accurately detect that the hour wheel 275 has reached the first reference position.

(6) When the hour / minute hand motor 26 is stopped every 20 minutes and the 24-hour hand light sensor 7 is operated, the detection hole 281A of the 24-hour intermediate wheel 281 can be detected continuously twice by the 24-hour hand light sensor 7. Is formed. As a result, even when the 24-hour hand light sensor 7 cannot detect the detection hole 281A for the first time due to component variations or backlash, the detection hole 281A is detected by the second and subsequent detections. Since there is an opportunity, the possibility of erroneous detection of the detection hole 281A is reduced, and detection can be performed more reliably.

(7) Since the hour / minute hand light sensor 6 and the 24-hour hand light sensor 7 are constituted by non-contact type light sensors, the durability is better than that of the contact type sensor. In addition, since the detection holes 275A and 281A are through-holes, the timing for detecting the respective reference positions of the hour wheel 275 and the 24-hour intermediate wheel 281 can be easily set only by appropriately setting the size and shape of the detection holes 275A and 281A. Can be set to

[Modification of the present invention]
It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
In the above-described embodiment, the detection hole 281A that is the second detected portion is formed in the 24-hour intermediate wheel 281. However, the second detected portion is a 24-hour rotating at a 24-hour cycle like the 24-hour intermediate wheel 281. The vehicle 282 may be provided. Therefore, since the second detected portion can be provided in both the 24-hour intermediate wheel 281 and the 24-hour wheel 282, restrictions on the arrangement of the 24-hour hand light sensor 7 can be reduced.

  In the embodiment, the detection hole 281A as the second detected portion is provided so as to be detectable by the 24-hour hand light sensor 7 as the second position detecting means at any position from 23:20 to 24:00, for example. However, the second detected portion of the present invention is provided so that at least the second gear reaches the second reference position before the first gear reaches the first reference position. Just do it. Therefore, unlike the present embodiment, the detection hole 281A does not have to have a rotation angle detection range of 40 minutes, and may be formed only at the position of 23:20, for example.

  In the above embodiment, the detection hole 281A as the second detected portion is provided so as to be detected with respect to a rotation angle of, for example, 23:20 to 40 minutes. The part may be provided so that 90 minutes before and after 24 o'clock is in the detection range in consideration of component variations and the effect of backlash.

The second gear of the present invention is not limited to a 24-hour intermediate wheel, and the same effect can be obtained even with a gear for calendar display, month display, year display, leap year display, day display, etc. Is obtained.
In the embodiment, the second hand is driven by an independent second hand motor. However, all of the second, hour, minute, and 24-hour hands may be driven to rotate by a single common motor. Alternatively, the second hand and the minute hand may be rotationally driven by one motor, and the hour hand and the 24-hour hand may be rotationally driven by another motor.

  In the above-described embodiment, the case where the second gear is a 24-hour wheel has been described. For example, even when only the conventional hour and minute hands are displayed without the 24-hour hand, the second gear is provided to engage with the hour wheel. The detection time when detecting the position of the hour hand can be shortened.

In addition, the best configuration, method and the like for carrying out the present invention have been disclosed above, but the present invention is not limited to this. That is, the invention has been illustrated and described with particular reference to certain specific embodiments, but without departing from the spirit and scope of the invention, Various modifications can be made by those skilled in the art in terms of material, quantity, and other detailed configurations.
Therefore, the description limited to the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such is included in this invention.

The top view which shows the electronic timepiece which concerns on one Embodiment of this invention. The top view which looked at the internal structure of the said electronic timepiece from the back cover side. The top view which looked at the internal structure of the said electronic timepiece from the time display side. The top view which looked at a part of internal structure of the electronic timepiece from the time display side. FIG. 3 is a side sectional view of the pointer driving means of the electronic timepiece. FIG. 3 is a side sectional view of the pointer driving means of the electronic timepiece. The block diagram which shows the structure of the position detection means of the hand of the said electronic timepiece. The flowchart which shows the position detection process of the hand of the said electronic timepiece.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electronic timepiece, 2C ... Hour hand, 6 ... Hour / minute hand light sensor (first position detecting means), 7 ... 24 hour hand light sensor (second position detecting means), 9A ... 24 hour hand, 26 ... Hour / minute hand motor, 61 ... First light emitting element (first light emitting means), 62... First light receiving element (first light receiving means), 71... Second light emitting element (second light emitting means), 72. Light receiving means), 275..., Hour wheel (first gear), 275A... Detection hole (first detected portion), 281... 24 hour intermediate wheel (second gear), 281A.

Claims (7)

A motor,
A first gear rotated by the motor;
A second gear to which rotation of the first gear is transmitted and a rotational speed with respect to the motor is slower than the first gear;
First position detecting means for detecting that the first gear is at a predetermined first reference position;
Second position detecting means for detecting that the second gear is at a predetermined second reference position;
Detection control means for controlling the operation of the first position detection means and the second position detection means;
An electronic timepiece comprising:
The first position detecting means includes
When the second gear is further rotated by a predetermined angle after the second position detecting means detects that the second gear is at the second reference position, the first gear is at the first reference position. Is set to detect that
The detection control means includes
In a first gear position detection mode in which the motor is driven to detect that the first gear has moved to the first reference position,
Activating the second position detecting means to detect that the second gear is in the second reference position;
After detecting that the second gear is in the second reference position, the first position detecting means is operated to detect that the first gear is in the first reference position. An electronic timepiece characterized by that. The electronic timepiece according to claim 1,
A rotation control means for controlling the motor;
The rotation control means includes
The rotational speed of the motor until the second gear reaches the second reference position is controlled at a higher speed than the rotational speed of the motor until the first gear reaches the first reference position. An electronic watch. The electronic timepiece according to claim 1 or 2,
The first gear has a first detected portion that is detected by the first position detecting means,
The second gear has a second detected portion that is detected by the second position detecting means,
The first detected part and the second detected part are:
The electronic timepiece is set so that the second gear reaches the second reference position before the first gear reaches the first reference position. The electronic timepiece according to claim 3,
The second detected portion and the second position detecting means are
The second detected portion is formed so as to be detectable by the second position detecting means until at least the first gear reaches the first reference position after the second gear reaches the second reference position. An electronic timepiece characterized by being made. The electronic timepiece according to claim 3 or 4,
The second position detecting means is activated every time the second gear rotates by a predetermined angle,
The electronic timepiece is characterized in that the second detected portion is formed to be detectable at least twice continuously by the second position detecting means. The electronic timepiece according to any one of claims 3 to 5,
The first detected part is a first through hole that penetrates the first gear,
The first position detecting means is a first optical sensor having first light emitting means for emitting detection light to the first through hole and first light receiving means for receiving the detection light passing through the first through hole. ,
The second detected part is a second through hole penetrating the second gear,
The second position detecting means is a second optical sensor having second light emitting means for emitting detection light to the second through hole and second light receiving means for receiving the detection light passing through the second through hole. An electronic timepiece characterized by that. The electronic timepiece according to any one of claims 1 to 6,
An hour hand coupled to the first gear;
A 24-hour hand connected to the second gear rotating at a reduction ratio of 1: 2 with respect to the first gear and displaying 24 hours per rotation;
An electronic timepiece characterized by comprising:

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