JP2017215152A - Electronic clock - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic clock capable of detecting a reference position of an indication member within a shorter time than its detection cycle even if the detection cycle in normal hand movement operation is long and the reference position passes by at faster timing than the detection cycle.SOLUTION: A radio wave modification clock includes: a time display unit including a dial, an hour hand, a minute hand and a second hand; a first detection unit 50 and a second detection unit 60 for detecting a reference position in a rotation direction of the hour hand, minute hand and second hand every hour; and a control unit 70 for controlling rotation of the hour hand, minute hand and second hand and detection of the reference position by the first detection unit 50 and second detection unit 60. The control unit 70 controls them to detect the reference position while rotating the hour hand, minute hand and second hand in a direction at the time of normal hand movement operation after rotating them in an opposite direction by a first rotation amount.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electronic timepiece.

  In an electronic timepiece that displays time by pointing an indicator with a plurality of indicating members such as hands, for example, the indicating member is at a specific position (for example, a rotational position when a specific index such as “12” is indicated). Some have a position detection unit for detection. In particular, for example, a radio-controlled timepiece that receives a signal to acquire highly accurate time information and forcibly drives the indicating member based on the time information to display the highly accurate time on the indicating member. Needs to know the current position of the pointing member in order to drive the pointing member to the correct position.

  As such an electronic timepiece, for example, in a minute / second wheel train associated with the minute hand and the second hand, a detection hole formed in a fifth wheel meshing with a rotor of a step motor, and a fourth wheel (second hand number) In some cases, the detection hole formed in the position detection wheel rotating at the same angular speed as the vehicle) overlaps in the axial direction at a rate of once per minute.

  In this case, when the electronic timepiece is normally moving, the positions of the minute hand and the second hand are correct depending on whether or not the above-described overlap can be detected by a photodetector at a predetermined timing (for example, at an interval of 1 minute). It is determined whether or not. If the overlap can be detected at a predetermined timing, it is determined that the position is correct. If the overlap cannot be detected at a preset timing, that is, if the rotational position of the rotor that drives the minute / second wheel train is shifted, whether or not the overlap can be detected thereafter at intervals of 1 second. A search is performed to identify the timing at which the overlap was detected. Then, the position can be corrected based on the amount of deviation between the identified timing and the above-described predetermined timing.

  Here, since the detection hole of the fifth wheel and the detection hole of the position detection vehicle always overlap at a cycle of once per minute, even if the above-mentioned overlap cannot be detected, the overlap is surely made within the next one minute. The position of the minute / second hand can be corrected within one minute from the preset timing.

  By the way, in the above-described example, the detection holes are formed in the position detection wheel that rotates once in one minute and the fifth wheel that rotates at a higher speed than the position detection wheel. Although the detection holes are formed in the fourth wheel and the second wheel, the position detection unit detects the overlap of the detection holes of the fourth wheel and the detection wheel of the second wheel. An electronic timepiece provided has been proposed (see, for example, Patent Document 1).

JP2013-250091A

  In the electronic timepiece described in Patent Document 1, the detection hole of the fourth wheel and the detection hole of the second wheel are overlapped in the axial direction at a cycle of once per hour. Therefore, when the electronic timepiece performs normal hand movement, the overlap between the two detection holes is once per hour, so the timing preset as the detection timing is once per hour. .

  If the position detection means fails to detect the overlap at a preset timing, then further searching for whether or not the overlap can be detected at intervals of 1 second will result in a maximum of 59 minutes 58 seconds later. There is also a possibility that the overlap cannot be detected. In other words, if the overlap of the detection holes is shifted in the delay direction of the clock, it can be detected at the very initial stage of the search for one hour. It will be detected around the end of the search.

  As described above, it takes too much time to detect that the pointing member is in a specific position as much as one hour. In addition, if the detection cannot be performed at a predetermined timing and then the detection is repeated at intervals of 1 second, the detection operation needs to be repeated 3598 times until 59 minutes and 58 seconds at the maximum, and power consumption for the detection operation is consumed. Is big.

  This problem is not limited to the detection holes formed in the fourth and second cars, but are formed in the fourth and third cars, and the third and second cars. The same applies to the case where the period of overlap of the detection holes is long (for example, 10 minutes or more), such as those that are performed by normal hand movement. Further, the detection holes are formed in each of the two or more wheel wheels, and the position detection unit is not limited to the detection of the overlap in the axial direction of the two or more detection holes. Even if the reference position of one indication member is detected, the same problem may occur when the detection cycle is long (for example, 1 hour or more) in a normal hand movement operation.

  The present invention has been made in view of the above circumstances, and the detection cycle is long in a normal hand movement operation, and even when the reference position passes at a timing earlier than the detection cycle, the detection is performed. It is an object of the present invention to provide an electronic timepiece that can detect the reference position of the pointing member within a time shorter than the period.

The present invention includes a time display unit that displays an hour by pointing an index with an indicator member that rotates in a certain direction, a position detector that detects a reference position in the direction of rotation of the indicator member at regular intervals, A control unit that controls rotation of the pointing member and detection of the reference position of the position detection unit, and the control unit is capable of detecting the reference position for each predetermined time by the position detection unit. If not, the indicator member is rotated in a direction opposite to the predetermined direction by a preset first rotation amount less than half of one rotation of the indicator member, and then the indicator member is The electronic timepiece controls the indication member and the position detection unit so that the reference position is detected by the position detection member while rotating in a fixed direction.

  According to the electronic timepiece of the invention, even when the detection cycle is long in a normal hand movement operation and the reference position passes at a timing earlier than the detection cycle, the detection cycle is longer than the detection cycle. The reference position of the pointing member can be detected in a short time.

It is a top view which shows the radio wave correction timepiece which is one Embodiment of the electronic timepiece which concerns on this invention. It is a perspective view which shows the step motor, drive wheel train, detection part, and control part which were provided in the inside of the radio wave correction timepiece. FIG. 3 is a plan view of the step motor and drive wheel train of FIG. 2, (A) is a view seen from the back cover side of the radio wave correction watch, and (B) is a view seen from the dial side of the radio wave correction watch. Show. It is a figure which shows the train wheel (gear) in which the detection hole was formed, (A) is the 4th wheel, (B) is the 3rd wheel, (C) is the 2nd wheel, (D) is the hour wheel, ) Indicates the second intermediate car. Sectional drawing which shows a mode that the LED chip and the phototransistor are arrange | positioned in the axial position where the detection hole of the hour wheel, the detection hole of the fourth wheel, the detection hole of the third wheel, and the detection hole of the second wheel overlap. It is. It is a flowchart which shows the operation | movement which searches the reference position of a time-train system by a control part. It is a flowchart which shows the operation | movement which searches the reference position of a minute second wheel train system by a control part. It is a flowchart which shows the modification of the control in which a control part searches the reference position of a minute / second wheel train system.

Hereinafter, embodiments of an electronic timepiece according to the invention will be described with reference to the drawings.
<Configuration of radio-controlled watch>
FIG. 1 is a plan view showing a radio-controlled timepiece 1 that is an embodiment of an electronic timepiece according to the present invention, and FIG. 2 is a step motor, a drive wheel train, a detection unit 50 provided in the radio-controlled timepiece 1. It is a perspective view which shows 60 (an example of a position detection part) and the control part 70 (an example of a control part). 3 is a plan view of the step motor and the drive wheel train of FIG. 2. FIG. 3A is a view seen from the back cover side of the radio-controlled timepiece 1, and FIG. The figure seen from the side of each is shown.

  As shown in FIG. 1, the radio-controlled timepiece 1 of the present embodiment includes an hour hand 4 (an example of an indicating member) and a minute hand 5 (an example of an indicating member) that rotate an index 3 displayed on a dial 2 in a certain direction (clockwise direction). The time is displayed by pointing with an example of the indicating member) and the second hand 6 (an example of the indicating member). That is, the dial 2, the hour hand 4, the minute hand 5, and the second hand 6 are examples of a time display unit.

  The radio-controlled timepiece 1 includes an antenna that receives a signal including time information (for example, a standard radio wave), step motors 31 and 41 that drive the hands (hour hand 4, minute hand 5, and second hand 6) and a driving wheel train. 10, 20 and the reference position in the direction of rotation of each pointer detected by the detection units 50, 60 are detected at regular intervals, and each pointer indicates the correct time based on the radio wave received by the antenna. And a control unit 70 composed of an IC or the like for controlling the rotation of the step motors 31 and 41.

  Here, as shown in FIGS. 2 and 3, the radio-controlled timepiece 1 includes a first step motor 31 that drives the hour hand 4 and a first drive wheel train 10. In addition to the hour hand 4, the first drive wheel train 10 also drives a date plate that is an indicating member for displaying the date, but the description of the date plate is omitted.

  The radio-controlled timepiece 1 also includes a second step motor 41 and a second drive wheel train 20 that drive the minute hand 5 and the second hand 6. In the following, the first step motor 31 and the first drive wheel train 10 are referred to as an hour wheel train system, and the second step motor 41 and the second drive wheel train 20 are referred to as a minute / second train wheel system.

  The first drive wheel train 10 includes a first intermediate wheel 11, a second intermediate wheel 12, a third intermediate wheel 13, and an hour wheel 14. The second intermediate wheel 12 may partially overlap a second drive wheel train 20 described later, but a detection hole 12a described later formed in the second intermediate wheel 12 has a second drive wheel train 20. It is a part that does not overlap. The hour wheel 14 is a portion overlapping the second drive wheel train 20. The first drive wheel train 10 transmits the driving force of the first step motor 31 in the order of the first hour intermediate wheel 11, the second hour intermediate wheel 12, the third hour intermediate wheel 13, and the hour wheel 14.

  As shown in FIG. 3, the second intermediate wheel 12 is formed with one detection hole 12a penetrating the gear in the axial direction. The second intermediate wheel 12 is arranged at a position that does not overlap the hour wheel 14 in a plan view (a surface viewed in a direction orthogonal to the axial direction of the drive wheel trains 10 and 20).

FIG. 4 is a diagram showing a train wheel (gear) in which detection holes 22a, 23a, 24a, 14a, and 12a are formed. (A) is a fourth wheel 22 and (B) is a third wheel 23, (C ) Indicates the second wheel 24, (D) indicates the hour wheel 14, and (E) indicates the second intermediate wheel 12.
The hour hand 4 is fixed to the hour wheel 14 and, as shown in FIG. 4D, eleven detection holes 14a penetrating the gear in the axial direction are formed. The eleven detection holes 14 a are formed around the rotation center of the hour wheel 14 in the circumferential direction at an angular interval of 30 degrees. The angular interval between the two detection holes 14a, 14a at both ends of the eleven detection holes 14a is 60 degrees.

  The controller 70 controls the driving of the first step motor 31 so that the hour wheel 14 is rotated once around the axis in 12 hours during normal hand movement. At this time, the second intermediate wheel 12 makes one rotation around the axis in one hour. The second intermediate wheel 12 rotates once in response to the input of 60 steps to the first step motor 31, and the hour wheel 14 rotates 720 (= 60 × 12) steps to the first step motor 31. One rotation in response to the input. The reduction gear ratio of each wheel train of the first drive wheel train 10 is an example, and other reduction gear ratios may be used.

The second drive wheel train 20 includes a fifth wheel 21, a fourth wheel 22, a third wheel 23 and a second wheel 24, and the driving force of the second step motor 41 is supplied to the fifth wheel 21, fourth wheel 24. The data is transmitted in the order of the second wheel 22, the third wheel 23, and the second wheel 24. The second wheel 6 has a second hand 6 fixed thereto and, as shown in FIG. 4, one detection hole 22a penetrating the gear in the axial direction is formed.
As shown in FIG. 4, the third wheel & pinion 23 is formed with two detection holes 23 a penetrating the gear in the axial direction at an angular interval of 180 degrees with the rotation center interposed therebetween. The second wheel 24 is fixed with the minute hand 5 and, as shown in FIG. 4, one detection hole 24a is formed through the gear in the axial direction.

  Further, the control unit 70 causes the fourth wheel 22 to make one rotation around the axis in one minute and the third wheel 23 to make one rotation around the axis in eight minutes during normal hand movement (time display operation) In addition, the driving of the second step motor 41 is controlled so that the center wheel & pinion 24 is rotated once around the axis in one hour. At this time, the second intermediate wheel 12 makes one rotation around the axis in one hour.

  Note that the fourth wheel 22 rotates once in response to the input of 60 steps to the second step motor 41, and the third wheel 23 inputs 480 (= 60 × 8) steps to the second step motor 41. The second wheel 24 rotates once in response to an input of 3600 (= 60 × 60) steps to the second step motor 41. The reduction ratio of the third wheel & pinion 23 is an example, and other reduction ratios may be used.

  The second drive wheel train 20 includes a detection hole 22a of the fourth wheel 22, a detection hole 23a of the third wheel 23, and a detection hole 24a of the second wheel 24 in one hour during normal hand movement. The position in the rotational direction is adjusted once so that the positions in plan view coincide and overlap in the axial direction.

  Note that the two detection holes 23a of the third wheel & pinion 23 are longer in the circumferential direction than the other detection holes 22a and 24a. This is because the second wheel 24 and the fourth wheel 22 rotate on the same axis, so that the detection hole 24a and the detection hole 22a are easy to assemble, whereas the third wheel 23 is the second wheel 24 and fourth wheel. This is because the detection hole 23a is easy to be assembled in a state of overlapping with the detection holes 22a and 24a in a plan view because it is not coaxial with the number wheel 22. Therefore, the detection hole 23a may be a circle similar to the other detection holes 22a and 24a as long as the assembling property in the state where the detection holes 22a, 23a, and 24a are overlapped in the axial direction is not questioned.

The second wheel 24, the fourth wheel 22, and the hour wheel 14 have the coincident rotation center C, and are the rotation centers of the hour hand 4, the minute hand 5, and the second hand 6 as shown in FIG. 1. That is, the first drive wheel train 10 and the second drive wheel train 20 are arranged so that a part thereof overlaps on the same axis.
The detection hole 14a of the hour wheel 14 is axially aligned with the detection hole 22a of the fourth wheel 22, the detection hole 23a of the third wheel 23, and the detection hole 24a of the second wheel 24 overlapping in the axial direction. It is formed at the overlapping position.

  However, the hour wheel 14 is driven by the first step motor 31, while the fourth wheel 22, the third wheel 23 and the second wheel 24 are driven by the second step motor 41. That is, the hour wheel train hour wheel 14 and the minute / second wheel train fourth wheel 22, third wheel 23, and second wheel 24 can be rotated independently of each other.

  Therefore, the detection hole 22a of the fourth wheel 22, the detection hole 23a of the third wheel 23, and the detection hole 24a of the second wheel 24 are overlapped in the axial direction to assemble the second drive wheel train 20, and the detection hole of the hour wheel 14 is assembled. Even if the hour wheel 14 is assembled in a state where 14a does not overlap the detection hole 22a, the detection hole 23a, and the detection hole 24a, the first step motor 31 is driven to rotate the hour wheel 14 so that the hour wheel 14 The detection hole 14a can be overlaid on the detection hole 22a, the detection hole 23a, and the detection hole 24a.

  In addition, since 11 detection holes 14a of the hour wheel 14 are formed, the hour hand 4 fixed to the hour wheel 14 is set to 10 every hour from the time when 0:00 (12:00) 00:00 is indicated. The detection holes 14a, 22a, 23a, 24a are adjusted so as to overlap in the axial direction corresponding to the time (22:00) 00:00.

  However, since this is a structure for detecting the rotational position of the hour wheel 14 when the hour wheel 14 is rotated once, since the hour hand 4 indicates 0:00 (12:00) 00:00 The detection holes 14a, 22a, 23a, and 24a are not limited to those that are adjusted so as to overlap in the axial direction until 1 hour (22:00) 00:00 is indicated every other hour.

  Accordingly, the detection holes 14a, 22a, 23a, and 24a from when the hour hand 4 indicates 1 o'clock (13 o'clock) 00 min 00 sec until every 1 hour indicates 11 o'clock (23 o'clock) 00 min 00 sec. May be adjusted to overlap in the axial direction, or every hour from when the hour hand 4 points to 23 o'clock (11 o'clock) 00:00, it will indicate 9 o'clock (21 o'clock) 00:00 Until then, the detection holes 14a, 22a, 23a, 24a may be adjusted so as to overlap in the axial direction.

  The radio-controlled timepiece 1 is arranged on both sides in the axial direction in which the detection holes 14a, 22a, 23a, 24a described above overlap each other at a specific position, and the axial direction of the four detection holes 14a, 22a, 23a, 24a. A second detection unit 60 that detects the overlap, and a first detection that detects the detection hole 12a by being disposed at both ends in the axial direction penetrating the detection hole 12a at a specific position in the rotation direction of the second intermediate wheel 12 Part 50.

  The first detection unit 50 includes an LED chip 51 that emits light, and a phototransistor 52 that detects light emitted from the LED chip 51. Since the gear of the second intermediate wheel 12 is arranged between the LED chip 51 and the phototransistor 52, many of the one hour in which the second intermediate wheel 12 makes one rotation is the LED chip. The light emitted from 51 is blocked by the gear of the second intermediate wheel and does not reach the phototransistor 52, and the phototransistor 52 does not detect the light.

  However, only when the detection hole 12a of the second intermediate wheel 12 passes between the LED chip 51 and the phototransistor 52, the light emitted from the LED chip 51 reaches the phototransistor 52, and the phototransistor 52 Detect light. The detection result of light by the phototransistor 52 is input to the control unit 70. That is, the control unit 70 detects the rotational position of the first drive wheel train 10 once an hour, and stores the detected position in the storage unit 71 as the reference position of the time wheel train system.

  5 shows the LED chip 61 at a position where the detection hole 14a of the hour wheel 14, the detection hole 22a of the fourth wheel 22, the detection hole 23a of the third wheel 23, and the detection hole 24a of the second wheel 24 are overlapped in the axial direction. 2 is a cross-sectional view showing a state in which a phototransistor 62 is arranged.

  Similarly to the first detection unit 50, the second detection unit 60 includes an LED chip 61 that emits light and a phototransistor 62 that detects light emitted from the LED chip 61. Since the hour wheel 14, the fourth wheel 22, the third wheel 23 and the second wheel 24 are disposed between the LED chip 61 and the phototransistor 62, the hour wheel 14, the fourth wheel 22 and the third wheel 24 are arranged. During most of the period in which the car 23 and the second wheel 24 are rotating, the light emitted from the LED chip 61 is any of the hour wheel 14, the fourth wheel 22, the third wheel 23, and the second wheel 24. The phototransistor 62 does not reach the phototransistor 62 because it is blocked by the gear, and the phototransistor 62 does not detect light.

  However, when the four detection holes 14a, 22a, 23a, and 24a overlap in the axial direction, the light from the LED chip 61 reaches the phototransistor 62, and the phototransistor 62 detects the light. The detection result of light by the phototransistor 62 is input to the control unit 70. That is, the control unit 70 detects the rotational position of the second drive wheel train 20 once an hour, and uses the detected position as the reference position (reference position) of the minute / second wheel train system. Remember me.

  The timing at which the phototransistor 52 detects light and the timing at which the phototransistor 62 detects light are not necessarily the same, but the time difference between the timing at which the phototransistor 52 detects light and the timing at which the phototransistor 62 detects light ( The difference in the number of steps for driving the first step motor 31) has a correspondence relationship that is always a constant reference as long as each step motor 31, 41 and each drive wheel train 10, 20 are operating normally. And never change. However, this time difference may be a different value depending on individual differences for each radio-controlled timepiece 1.

The control unit 70 includes a storage unit 71 and a determination unit 72.
The storage unit 71 stores the time from the reference position of the hour train system where the phototransistor 52 detects light after the radio-controlled timepiece 1 is actually assembled to the reference position of the minute / second train system where the phototransistor 62 detects light. The number of steps that has driven the first step motor 31 is stored as a reference number of steps. The number of steps of this reference is such that the phototransistor 62 can detect light through the detection hole 14a of the hour wheel 14 from the reference position of the detection hole 12a of the second intermediate wheel 12 where the phototransistor 52 was able to detect light. It corresponds to the phase difference to the position.

  Therefore, the control unit 70 drives the first step motor 31 by the reference number of steps corresponding to the phase difference from the reference position of the hour wheel train system where the detection hole 12a of the second intermediate wheel 12 is detected. Accordingly, the detection hole 14a of the hour wheel 14 can be arranged at the reference position of the minute / second wheel train system.

  During the subsequent use of the radio-controlled timepiece 1, the control unit 70 causes the LED chip 51 corresponding to the time wheel train system to emit light at the reference position of the time wheel train system stored in the storage unit 71, and the phototransistor 52. Makes the determination unit 72 determine whether or not light can be detected. When the phototransistor 52 can detect light, the determination unit 72 determines that the reference position of the hour wheel train system is not shifted and the rotation position of the hour hand is correct.

  On the other hand, when the phototransistor 52 cannot detect light, the rotor of the first step motor 31 is instructed by the control unit 70, for example, due to an impact or an external magnetic field applied to the radio-controlled timepiece 1. This is a case where the wheel rotates without corresponding to the number of steps, and the determination unit 72 determines that the reference position of the hour wheel train is off and the rotation position of the hour hand is incorrect.

  In addition, the control unit 70 causes the LED chip 61 corresponding to the minute / second wheel train system to emit light at the reference position of the minute / second wheel train system stored in the storage unit 71 so that the phototransistor 62 detects the light. The determination part 72 is made to determine whether it can do. When the phototransistor 62 can detect light, the determination unit 72 determines that the reference position of the minute / second wheel train is not shifted, and the rotational positions of the minute hand and the second hand are correct.

  On the other hand, when the phototransistor 62 cannot detect light, for example, an impact or an external magnetic field is applied to the radio-controlled timepiece 1 to cause the rotor of the first step motor 31 and the second step motor. This is a case where at least one of the 41 rotors rotates without corresponding to the number of steps commanded from the control unit 70, and the number of steps corresponding to the phase difference between the hour wheel train system and the minute / second train system. Is deviated from the reference step number corresponding to the phase difference stored in the storage unit 71. In this case, the determination unit 72 determines that the reference position of the minute / second wheel train is shifted and the time display is incorrect.

  When the determination unit 72 determines that the time wheel train reference position is shifted, the control unit 70 performs control to search for the time wheel train reference position. That is, the control unit 70 searches for the reference position while driving the first step motor 31 of the hour wheel train system step by step. That is, the control unit 70 drives the first step motor 31 of the hour wheel train system step by step and causes the LED chip 51 to emit light for each step, so that the position where the phototransistor 52 detects the light is set to the hour wheel. It is detected as the reference position of the row system. Details of the control of the drive of the first step motor 31 and the control of the first detector 50 by the controller 70 will be described later.

  The reference position shift is always an even number of steps depending on the relationship with the motor steering. In such a case, the LED chip 51 is caused to emit light for each step while being driven step by step to search for the reference position. Instead of performing this, it is only necessary to search the reference position by causing the LED chip 51 to emit light every two steps while being driven step by step.

  When it is determined that the reference position of the minute / second wheel train is shifted, the control unit 70 performs control to search for the reference position of the minute / second wheel train. That is, the control unit 70 first drives the hour wheel train from the reference position of the hour wheel train in the direction of the normal hand movement by the reference number of steps corresponding to the phase difference stored in the storage unit 71. At this time, the hour wheel train hour wheel 14 is in a state where the detection hole 14a is stopped at the reference position of the minute / second wheel train.

  Next, with the detection hole 14a of the hour wheel 14 stopped at the reference position of the minute / second wheel train, the controller 70 drives the second step motor 41 of the minute / second wheel train one step at a time. Search for a location. That is, the control unit 70 drives the second step motor 41 of the minute / second wheel train one step at a time and causes the LED chip 61 to emit light for each step to determine the position where the phototransistor 62 detects the light. It is specified as the reference position of the second wheel train system. Details of the control of the driving of the second step motor 41 and the control of the second detector 60 by the controller 70 will be described later.

  For the same reason as in the hour wheel train system, the minute / second train system does not search the reference position by driving the LED chip 61 for each step while driving step by step. The reference position may be searched by causing the LED chip 61 to emit light every two steps while being driven step by step.

<Operation of the radio-controlled clock>
In the radio-controlled timepiece 1 configured as described above, when the second drive wheel train 20 is assembled, the second detection unit 60 detects the detection holes 22a, 23a, and 24a. The detection holes 22a, 23a, and 24a of the wheel 22, the third wheel 23, and the second wheel 24 are positioned so as to be overlapped in the axial direction.
When assembling, only these three wheel trains (the fourth wheel 22, the third wheel 23, and the second wheel 24) may be aligned at the positions detected by the second detector 60.

  Next, when assembling the hour wheel 14 of the first drive wheel train 10 coaxially with the second wheel 24 and the fourth wheel 22, the detection hole 14 a of the hour wheel 14 is detected by the three detections of the second drive wheel train 20. There is no need to overlap the holes 22a, 23a, 24a. Further, the rotational position relationship (phase relationship) between the detection hole 14a of the hour wheel 14 and the detection hole 12a of the second intermediate wheel 12 need not be a specific positional relationship.

  That is, the train wheel (gear) to be detected by the first detector 50 is the second intermediate wheel 12, and the train wheel (gear) detected by the second detector 60 is the hour wheel 14, The second wheel 24, the third wheel 23, and the fourth wheel 22, and the target gear detected by the first detection unit 50 and the target gear detected by the second detection unit 60 are not common.

Therefore, the radio-controlled timepiece 1 is configured to align the rotational positions of four or more gears (number wheels) in a specific state when assembling with the first drive wheel train 10 and the second drive wheel train 20. In comparison, the difficulty of assembly can be reduced.
Further, since the number of wheel trains that are used for detecting the rotational position and that overlap in the axial direction is reduced, the thickness of the radio-controlled timepiece 1 can be reduced.

In the assembled radio-controlled timepiece 1, the reference step corresponding to the reference position of the hour wheel train system, the reference position of the minute / second wheel train system, and the phase difference is stored in the storage unit 71.
FIG. 6 is a flowchart showing an operation of searching for the reference position of the hour wheel train system by the control unit 70. At the time of the normal hand movement in which the time is displayed, the control unit 70 determines a predetermined timing (1) when the detection hole 12a of the second intermediate wheel 12 passes the reference position of the time wheel train system stored in the storage unit 71. Whether or not the phototransistor 52 has detected light, that is, whether or not the reference position of the hour wheel train system has been detected (S11 in FIG. 6).

When it can be detected (YES in S11), it is determined whether it can be similarly detected at the next predetermined timing after one hour.
When it cannot be detected (NO in S11), the control unit 70 is less than half of one rotation of the second intermediate wheel 12 in the direction opposite to the rotation direction during normal hand movement of the hour wheel train. The first step motor 31 is controlled to rotate by a first rotation amount set in advance, for example, 10 steps of the first step motor 31. (S12)

The 10 steps of the first step motor 31 correspond to the amount of rotation by which the second intermediate wheel 12 rotates by an angle of 60 [degrees].
The first rotation amount for rotating the hour wheel train in the direction opposite to the rotation direction at the time of normal hand movement is not limited to the above-described 10 steps, and is 2 steps or more and 30 steps (second time). If it is less than half of one rotation of the intermediate wheel 12, it may be 4 steps, 6 steps or 8 steps. In addition, since the deviation | shift of a rotor is usually several steps at most, it is preferable that the 1st rotation amount is set in 2 steps or more and 10 steps or less.

Thereafter, the controller 70 causes the LED chip 51 to emit light for each step while rotating the hour wheel train one step at a time by the first step motor 31 in the rotation direction during normal hand movement. Waiting for detection of light (S13, S14). When the phototransistor 52 detects light, the control by the control unit 70 to rotate the hour wheel train one step at a time in the rotation direction during normal hand movement ends.
Then, the control unit 70 resets the rotation position when the phototransistor 52 detects light and detects the reference position of the hour wheel train system as the reference position of the hour wheel train system, and stores it in the storage unit 71.

  The control unit 70 rotates the first step motor 31 in the direction opposite to the rotation direction at the time of normal hand movement in order to detect the reference position of the hour wheel train system. Rotation when rotating one step at a time in the direction of rotation is an angular velocity (for example, 10 [step / s] (= 1 [step / min] (= 1/60 [Hz])) faster than normal operation (1 [step / min] (= 1/60 [Hz])). 10 [Hz])).

  FIG. 7 is a flowchart showing an operation of searching for the reference position of the minute / second wheel train by the control unit 70. At the time of normal hand movement for displaying the time, the control unit 70 detects the detection hole 14a of the hour wheel 14, the detection hole 24a of the second wheel 24, the detection hole 23a of the third wheel 23, and the detection hole 22a of the fourth wheel 22. However, whether or not the phototransistor 62 has detected light at a predetermined timing (one cycle per hour) passing through the reference position of the minute / second wheel train stored in the storage unit 71, that is, the minute / second wheel It is determined whether or not a row system reference position has been detected (S21 in FIG. 7).

When it can be detected (YES in S21), it is determined whether or not it can be similarly detected at the next predetermined timing after one hour.
When it cannot be detected (NO in S21), the control unit 70 first sets the time train system from the reference position to the normal number of steps corresponding to the reference step number corresponding to the phase difference stored in the storage unit 71. The first step motor 31 is controlled so as to be rotated in the direction of rotation and stopped (S22). At this time, the hour wheel train hour wheel 14 is in a state where the detection hole 14a is stopped at the reference position of the minute / second wheel train.

  With the detection hole 14a of the hour wheel 14 stopped at the reference position of the minute / second wheel train, the control unit 70 moves the second / second wheel train in the direction opposite to the rotation direction during normal hand movement. The second step motor 41 is controlled to rotate by a preset second rotation amount that is less than half of one rotation of 24, for example, 60 steps of the second step motor 41 (S23).

The 10 steps of the second step motor 41 correspond to the rotation amount by which the fourth wheel & pinion 22 rotates by an angle of 60 [degrees].
The second rotation amount for rotating the minute / second wheel train in the direction opposite to the rotation direction at the time of normal hand movement is not limited to the above-described 10 steps. If it is less than half of one rotation of the vehicle 22, it may be 4 steps, 6 steps, or 8 steps. Since the rotor deviation is usually several steps at most, it is preferable that the second rotation amount is set to 2 steps or more and 10 steps or less.

Thereafter, the control unit 70 causes the LED chip 61 to emit light for each step while rotating the minute / second wheel train in the rotation direction of the normal hand movement step by step by the second step motor 41, and the phototransistor 62. Waits for detection of light (S24, S25). When the phototransistor 62 detects light, the control by the control unit 70 to rotate the minute / second wheel train one step at a time in the rotation direction during normal hand movement ends.
Then, the control unit 70 resets the rotation position when the phototransistor 62 detects light and detects the reference position of the minute / second train system as the reference position of the minute / second train system, and stores it in the storage unit 71. Let

  Note that the control unit 70 rotates the second step motor 41 in the direction opposite to the rotation direction at the time of normal hand movement in order to detect the reference position of the minute / second wheel train system. The rotation when rotating one step at a time in the rotational direction of the hour is an angular velocity (for example, 10 [step / s] (1 [step / min] (= 1/60 [Hz])) faster than that during normal hand movement. = 10 [Hz])).

  Thus, according to the radio-controlled timepiece 1 of the present embodiment, in the operation of detecting the reference position of the hour wheel train system and the reference position of the minute / second train system, the hour wheel train system and the minute / second train wheel system are After slightly rotating in the direction opposite to that during normal hand movement, detection is performed by rotating in the direction of rotation during normal hand movement from a position slightly rotated in the opposite direction. Therefore, the detection cycle is as long as 1 hour in normal hand movement operation, and the reference position is shifted in the direction of the timing (time advance direction) earlier than the reference position that should have been originally detected during normal hand movement. Compared to searching for whether the hour wheel train system or minute / second train system can be detected by simply rotating it in the normal direction, the reference position can be set in a short time. Can be detected.

  Even if the reference position is deviated in the timing direction (time delay direction) that was delayed from the reference position that should have been detected during normal hand movement, the hour wheel train or minute / second wheel The amount of rotation that rotates the train in the direction opposite to the normal hand movement direction is very small compared to the original detection cycle, so the hour wheel train system or minute / second train train system is simply moved in the normal hand movement direction. Compared with the case where it is searched whether it can detect by rotating, it extends only slightly.

  Further, the radio-controlled timepiece 1 of the present embodiment is in a state where it is slightly rotated in the direction opposite to that during normal hand movement in the operation of detecting the reference position of the hour wheel train system and the reference position of the minute / second train system. When rotating in the direction of rotation during normal hand movement, rotation is performed faster (faster angular velocity) than in normal hand movement operation, so that the reference position can be detected at an earlier timing.

  In the radio-controlled timepiece 1 of the present embodiment, when the reference position of the hour wheel train cannot be detected during normal hand movement, the control unit 70 refers to the rotation direction of the hour wheel train during normal hand movement. Although it is controlled to rotate in the opposite direction (S11 in FIG. 6), the hour wheel train can detect the reference position every 60 steps, and it is detected in a shorter cycle than the minute / second train wheel system. Therefore, the hour wheel train system may be detected by rotating only the minute / second wheel train system in the opposite direction without rotating in the opposite direction.

<Modification>
In the radio-controlled timepiece 1 according to the above-described embodiment, the control unit 70 performs a rotation direction during normal hand movement (hereinafter referred to as forward rotation) for both searching for the reference position of the hour wheel train system and searching for the reference position of the minute / second wheel train system. It is controlled so that the number of steps rotated in the opposite direction to the direction is fixed at a constant value and rotated once in the forward direction from the rotation position rotated in the opposite direction. .

  However, the electronic timepiece of the present invention is not limited to this form, and the number of steps to rotate in the forward rotation direction after setting the number of steps to rotate in the opposite direction to a small value is set to a constant value (for example, If the search is not possible, set the number of steps to rotate in the opposite direction and the number of steps to rotate in the forward direction. The control unit 70 may perform control so that the search range is gradually expanded while increasing and the rotation in the opposite rotation direction and the rotation in the forward rotation direction are repeated a plurality of times.

  In this case, a predetermined upper limit is set for the number of repetitions of rotation in the opposite rotation direction and rotation in the forward rotation direction, and the number of repetitions (the same as the number of rotations in the opposite rotation direction) is predetermined. When the number of times is reached, the search based on the rotation in the forward rotation direction may be continued until the rotation is rotated once.

  FIG. 8 is a flowchart showing a modification of control in which the control unit 70 searches for the reference position of the minute / second wheel train system. In the modification shown in FIG. 8, the control unit 70 increases the number of steps N1 to rotate in the opposite rotation direction and the number of steps N2 (N2 = 2 × N1) to rotate in the normal rotation direction in stages (α steps). The first step motor 31, the second step motor 41, and the second step motor 41 so that the search range is gradually expanded and the rotation in the opposite rotation direction and the rotation in the forward rotation direction are repeated two or more times. The second detection unit 60 is controlled.

  Specifically, the control unit 70 includes a detection hole 14 a of the hour wheel 14, a detection hole 24 a of the second wheel 24, a detection hole 23 a of the third wheel 23, and a detection hole 22 a of the fourth wheel 22 in the storage unit 71. Whether or not the phototransistor 62 detects light at a predetermined timing (one time per hour) passing through the stored reference position of the minute / second wheel train system, that is, the reference position of the minute / second wheel train system is determined. It is determined whether or not it has been detected (S31 in FIG. 8).

  When it can be detected (YES in S31), it is determined whether it can be similarly detected at the next predetermined timing after one hour. When it cannot be detected (NO in S31), the control unit 70 first sets the time train system from the reference position to the normal number of steps corresponding to the reference step number corresponding to the phase difference stored in the storage unit 71. The first step motor 31 is controlled so as to be rotated in the direction of rotation and stopped (S32). At this time, the hour wheel train hour wheel 14 is in a state where the detection hole 14a is stopped at the reference position of the minute / second wheel train.

  While the detection hole 14a of the hour wheel 14 is stopped at the reference position of the minute / second wheel train, the control unit 70 rotates the minute / second wheel train in a direction opposite to the rotation direction during normal hand movement. The control unit 70 counts the number M (initial value 1) of rotations in the opposite direction, and determines whether M = 1 (first time) (S33).

  If it is the first time, the process proceeds to step 35 (S35). If it is not the first time but the second time or later, the number of steps N1 to be rotated in the opposite direction (initial value is, for example, 10) is increased by α steps (α is, for example, 10) (S34), and step 35 (S35 ) When it is the first time, the number of steps N1 remains at the initial value of 10.

  The initial value of the number of steps N1 is not limited to 10 steps, and may be 4 steps as long as it is 2 steps or more and less than 1800 steps (corresponding to half of one rotation of the center wheel & pinion 24). 6 steps or 8 steps may be used. Further, the increasing number of steps α is not limited to 10 steps, and may be 4 steps, 6 steps, or 8 steps as long as it is 2 steps or more and less than 30 steps.

  Then, the control unit 70 controls the second step motor 41 so that the minute / second wheel train is rotated by the N1 step of the second step motor 41 in the direction opposite to the rotation direction during normal hand movement. (S35).

  Thereafter, the controller 70 rotates the minute / second wheel train in the normal rotation direction by one step (or two steps) of the second step motor 41, while the number of rotation steps in the forward rotation direction is N2. The LED chip 61 is caused to emit light every one step (or two steps) until it reaches (for example, twice N1; the second rotation amount), and waits for the phototransistor 62 to detect light (S36). , S37, S38). The number of steps N2 of rotation in the forward rotation direction is not limited to twice the number of steps N1, and may be a value larger than the number of steps N1. Further, the step number N2 may not increase in conjunction with the step number N1 increasing by α steps, or may be a constant value.

  When the phototransistor 62 detects light, the control by the controller 70 for rotating the minute / second wheel train one step at a time in the rotation direction of the normal hand movement is completed (YES in S37). ).

  On the other hand, the reference position could not be detected in the first search range (for example, −10 step to +10 step) from the rotation position rotated N1 steps in the opposite direction to the rotation position rotated N2 steps in the forward rotation direction. When (NO in S37 and YES in S38), the control unit 70 determines whether or not the number M of rotations in the opposite direction has reached a predetermined number (for example, three times) set in advance (S39). .

  The preset number of times contrasted with the number of times M is not limited to three, and there is no need to provide a limit as long as it is two or more. However, since the number M is the number of repetitions, even if the number of repetitions is too large, the time required for the repetition is wasted. Therefore, it is preferable to set the upper limit to about 3 times.

  When the predetermined number of times has not been reached (NO in S39), M is incremented by 1 in step 42 (S42), and the process returns to step 33 (S33). When the predetermined number of times has been reached (YES in S39), the process proceeds to step 40 (S40). Here, since M = 1 and the first search has just ended, the process returns to step 33 to perform the second search.

  In the second and subsequent searches, the number of steps N1 for performing the second and subsequent rotations in the opposite direction is increased by the number of steps α from the rotation position before the first rotation in the opposite direction (S34). Rotation in the opposite direction is performed, and in conjunction with this, the upper limit step number N2 of the search for each step in the forward rotation direction is also increased. That is, the second search range is, for example, −20 steps to +20 steps. Similarly, the third search range is, for example, −30 steps to +30 steps.

  When the reference position is detected as a result of the search in this way (YES in S37), the process returns to step 31 (S31), and detection is performed at the timing after the next one hour. On the other hand, if the reference position cannot be detected even when the number M of repetitions reaches the third predetermined value (NO in S37, YES in S38 and YES in S39), the minute / second hand wheel train is set to the correct position. The reference position detection operation (S40, S41) while rotating one step at a time in the rotation direction is continued to detect the reference position.

  As described above, in the radio-controlled timepiece 1 of the modified example, the control unit 70 is based on the rotation range of the first rotation amount in the opposite direction and the rotation range of the second rotation amount in the forward rotation direction therefrom. If the search cannot be performed after searching for the position, the search range is gradually expanded while increasing the number of steps to rotate in the opposite rotation direction and the number of steps to rotate in the normal rotation direction, and the opposite rotation direction. The rotation is controlled so as to repeat the rotation in the forward direction and the rotation in the forward rotation direction a plurality of times.

In this way, the search range in the opposite direction and the forward rotation direction is expanded and repeated, so that the search range is expanded only in the forward rotation direction after being rotated once in the opposite direction. The possibility that the reference position can be detected quickly can be increased.
Further, by providing an upper limit of repetition, it is possible to limit the time required to return to the original rotational position for repetition.

  In addition, although the radio wave correction timepiece 1 according to the embodiment and the modification described above performs time accuracy determination every hour, the electronic timepiece according to the present invention is not limited to this mode, and at shorter time intervals. The determination may be performed, or the determination may be performed at a longer time interval.

  In this case, the number of detection holes 12 a, 14 a, 22 a, 23 a, 24 a formed in the first driving wheel train 10 and the second driving wheel train 20 can be increased or decreased, Other wheel trains (gears) linked to the first drive train wheel 10, other wheel trains (gears) of the second drive train wheel 20, and second drive train trains For example, a detection hole may be formed in another wheel train (gear) linked to the gear 20.

  Although the embodiment and the modification described above are the radio-controlled timepiece 1, the electronic timepiece according to the present invention is not limited to the radio-controlled timepiece. In other words, the electronic timepiece according to the present invention is applied to all electronic timepieces that detect the position of a pointing member such as a hand, and is also applied to, for example, an electronic timepiece that corrects the indication of the hand based on a signal by GPS.

1 Radio-controlled watch 2 Dial 4 Hour hand 5 Minute hand 6 Second hand 12 Second hour intermediate wheel 12a, 14a, 22a, 23a, 24a Detection hole 14 Hour wheel 22 Fourth wheel 23 Third wheel 24 Second wheel 31 First step Motor 41 Second step motor 50 First detection unit 60 Second detection unit 70 Control unit

Claims (4)

A time display unit that displays the time by pointing the index with an indicating member that rotates in a certain direction;
A position detector for detecting a reference position in the direction of rotation of the pointing member at regular intervals;
A control unit that controls rotation of the pointing member and detection of the reference position of the position detection unit,
When the position detection unit cannot detect the reference position at every certain time, the control unit moves the pointing member in a direction opposite to the certain direction and a half of one rotation of the pointing member. The reference member and the reference member so that the position detection member detects the reference position while rotating the indicator member in the fixed direction after being rotated by a preset first rotation amount less than An electronic timepiece for controlling the position detection unit.   The control unit is configured to rotate the first rotation amount in the opposite direction of the pointing member when the position detection unit cannot detect the reference position for each predetermined time, and thereafter When the reference position cannot be detected by the position detection unit between the rotation of the second rotation amount set in advance in the certain direction, the first rotation amount and the second rotation amount are detected. The rotation amount of the indicator member is rotated by the first rotation amount in the opposite direction, and then the second rotation amount is rotated in the predetermined direction. The electronic timepiece according to claim 1, wherein the control for detecting the reference position by the position detection unit is repeated.   The control unit increases the first rotation amount and the second rotation amount, respectively, and then rotates the first rotation amount in the opposite direction of the pointing member and the fixed direction. When the number of repetitions of repeating the control for detecting the reference position by the position detecting means by rotating the second rotation amount reaches a predetermined number of times, the rotation in the constant direction is performed. The electronic timepiece according to claim 2, wherein control for detecting the reference position by the position detection unit is performed while continuing the operation.   The control unit is configured to determine the reference direction of the reference member for detecting the reference position by the position detection unit when the position detection unit fails to detect the reference position for each predetermined time. 4. The electronic timepiece according to claim 1, wherein the electronic timepiece is controlled so that an angular velocity of rotation of the indicator is faster than an angular velocity of rotation of the indication member for the time display in the fixed direction. 5. .