JPH07107550B2 - Twilight display watch - Google Patents

Description

The present invention relates to a timepiece having a dim light display function.

[Conventional technology]

Even when the sun is setting, during the so-called astronomical twilight, when the sky is not completely dark due to sunlight reflected and scattered in the upper atmosphere of the earth, it is not suitable for observing dark objects in astronomical observation. However, during the comparatively bright normal twilight of the sky just after sunset or just before sunrise, some outdoor activities are possible without special lighting.

It can be said that it is very convenient not only for astronomical observation but also for daily life if the function for distinguishing the above-mentioned twilight state is provided as an additional function of the timepiece. There wasn't.

[Problems to be solved by the invention]

The brightest planet can be seen when the sun sets 6.5 ° below the horizon, and when it reaches 18 ° below the horizon, the sky becomes completely dark. With the above conditions as boundary conditions, the period when the sun is between the horizon and 6.5 ° below the horizon is called normal twilight, and the period between the horizon and 18 ° below the horizon is called astronomical twilight. It is impossible to identify the twilight state unless the exact positional relationship with is known. To determine whether it is in the twilight state, the latitude of the point, the local sidereal time, and the exact sun position on the celestial sphere (right longitude and declination) are required.
The speed of the sun moving on the ecliptic on the celestial sphere is not constant because the orbit of the earth is elliptical. Furthermore, the ecliptic intersects the celestial equator at about 23.5 °, and the declination of the sun also changes seasonally. For example, if the sun position is simply displayed by a constant-speed hand that rotates once a day, the exact sun position on the celestial sphere cannot be displayed, and therefore the twilight state cannot be accurately determined. An object of the present invention is to provide a timepiece having a function of accurately distinguishing the above-mentioned twilight state with a simple train wheel structure.

[Means for solving problems]

The present invention has been made to solve the above-mentioned problems, and uses a timepiece having a display plate that makes one rotation per star day through an adjusting wheel from an hour wheel holding an hour hand, and uses the timepiece to display the sun on the display plate. The position is substantially displayed by printing or the like, and the horizon and the twilight limit line are displayed by holes or printing on the dial or the windshield that is arranged on the display plate, and the position is displayed on the display plate. By the overlapping state of the sun position and the horizon and twilight limit line provided on the dial or windshield, it is possible to accurately determine the twilight state with a simple train wheel configuration,
By providing a twilight display timepiece that allows you to know the twilight time of the day by knowing the sunset time and the end time of twilight on what month and day by rotating the display plate on the external operation unit. .

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

1 is a plan view of a twilight display timepiece having a constellation display function according to the present invention, FIG. 2 is a cross-sectional view showing a main part of a train wheel mechanism of the timepiece of FIG. 1, and FIG. 1 is a partial plan view showing the outline of the train wheel of the timepiece of FIG. 1, FIG. 4 is a plan view of a constellation display plate for displaying the sun position and constellations of the timepiece of FIG. 1, and FIG. It is a bottom view seen from the case back side of the timepiece of the figure.

In the figure, 1 is a clock with twilight indication, 2 is a constellation display plate, 3
Indicates an hour hand, 4 indicates a minute hand, and 5 indicates a second hand. 6 is a dial, which has a 12-hour scale at the position corresponding to the hour hand 3.
6a, a constellation display window 6b for seeing through the constellation display plate 2 and a twilight identification window 6c are provided, and the constellation display window 6b, the twilight identification window 6c and the constellation display plate 2 provide the first constellation display section 7 Is configured. In the first constellation display portion 7, the constellation display window 6b is an arc 6d showing declination + 35 ° which is the northern limit of the constellation display in the first constellation display portion 7 and a horizon line at the north latitude 35 °.
NE, E, SE, which indicates the direction, on the character portion 6 which is surrounded by an arc-shaped curve indicating 6e and faces the curve indicating the horizon 6e.
Characters 6f of S, SW, W and NW are drawn.

Constellation display plate 2 shows declination -55.6 ° to +35 from declination south of the zenith at 35 ° north latitude, which allows for horizontal refraction of 0.6 ° due to atmospheric difference.
The main bright stars 2a, the ecliptic 2b, and the Milky Way 2c up to ゜ are drawn from the center of rotation of the constellation display plate 2 toward the outer circumference at equal declination conditions. The number 2d from 0 to 23 indicating the right ascension on the outer circumference, and the sun position at noon (Japan Standard Time) on the 1st, 11th, and 21st of each month on the ecliptic 2b is 36 points. It is displayed as the sun position display part, and the month number 2f from 1 to 12 indicated by the corresponding month is drawn near the position of the first day of each month in the break 2e. Shows 12 o'clock position mark 6
By reading the right ascension corresponding to a ', the sidereal time can be known, and by reading the sun position on the ecliptic 2b corresponding to the moon day, the sun position on the celestial sphere can be known.

The twilight identification window 6c has an arc 6g indicating declination + 35 ° and declination -5.
It is drawn on the constellation display plate 2 placed under the dial 6 and surrounded by an arc 6h indicating 5.6 ° and an arc-shaped curve 6i indicating the astronomical twilight limit line at the zenith distance 108 ° at 35 ° north latitude. The sun position corresponding to the date on the ecliptic 2b is the twilight identification window.
It is configured to show that the sun is not dim when it is inside 6c, the daytime state when it is inside the constellation display window 6b, and the dim light when hidden under the dial 6. Has been done. Reference numeral 8 is a second constellation display portion drawn on the back cover 9 (shown in FIG. 5). From the declination + 35 ° which is not displayed on the first constellation display portion 7 in the central portion of the second constellation display portion 8, The main bright star 9a and the Milky Way 9b leading to the celestial north pole are drawn with equal declination conditions centered on the celestial north pole, and the numbers from 0 to 21 indicating the right ascension are inside the outer circumference. It is drawn at 45 ° intervals on the display 9c, and the twilight display clock 1 is set so that the numerical value 9c corresponding to the fixed star read on the first constellation display 7 is on top.
It is configured so that the location of the northern constellation can be known by rotating and looking at it. Furthermore, in the outermost part, the longitude of the Japanese Standard Time (East longitude 135
The scale of the month and day to indicate the mean noon
9d is engraved.

Next, the train wheel of the timepiece of this embodiment will be described.

In the figure, 10 is the fourth wheel and the second hand 5, and 11 is the center wheel and the minute hand 4.
However, 12 is a hour wheel, and the hour hand 3 is attached to each of them. Reference numeral 13 denotes a rear wheel of the day, which meshes with the center pinion 11a of the center wheel 11 and the tubular gear 12a of the hour wheel 12, and the hour wheel 12 is constituted by an hour wheel gear 12a and an hour wheel pinion 12b.

Further, 14 is an adjusting wheel, which is composed of an adjusting gear 14a and an adjusting wheel pinion 14b, is loosely engaged with an adjusting wheel pin 16 fixed to a main plate 15, and a back plate 17 holds a tataki.
A slip function unit 14c that slips under a load of a predetermined torque or more between the adjusting gear 14a that meshes with the hour wheel pinion 12b and the adjusting wheel pinion 14b that meshes with the constellation gear 18 as a display wheel in which the constellation display plate 2 is integrated. Is provided.

The constellation gear 18 has the constellation display unit 2 fixed to the side end thereof, is loosely engaged with the hour wheel 12, and is sandwiched between the back plate 17 and the constellation display plate seat 19 including the tattoo.

Further, the hour wheel 12 is sandwiched between the main plate 15 and the back plate 17 together with the needle seat 20 for removing the influence of the backlash of the train wheel, and the pinwheel is held. Reference numeral 21 denotes a correction intermediary vehicle, which is composed of a correction intermediary gear 21a that meshes with the adjusting vehicle pinion 14b and a correction intermediary pinion 21b that meshes with the correction vehicle 22, and is loosely engaged with the correction intermediary vehicle pin 23 fixed to the main plate 15 Since the plate 17 holds the tataki, the rotational movement from the crown 24, which is an external operating member, to the correction wheel 22 by the winding stem 25 does not idle in the normal position 24a and is not transmitted, but is integrated with the winding stem in the one-step pulling position 24b. However, since the engagement with the correction vehicle 22 is released at the two-step pulling position 24c, the rotational movement from the crown 24 is corrected only at the one-step pulling position 24b via the correction vehicle 22 and the correction intermediary vehicle 21. Is configured to be transmitted to.

Next, the operation will be described.

As is known, the reduction ratio from the fourth wheel 10 to the minute pinion 11a is 1/6.
0 is set, and minute wheel 12 is passed from minute Kana 11a via Hino Ura 13
By setting the reduction ratio to 1/12, the hour wheel 12 makes one revolution in 12 hours.

1 average star day, that is, the average automatic cycle for the vernal equinox of the earth is 23 hours 56 minutes 4.091 seconds at the time of the average sun, and in order to match the apparent movement speed of the star with the rotation speed of the constellation display plate 2, the constellation gear 18 is 1 day At (24 hours / 23 hours 56 minutes 4.091
It is necessary to configure the number of teeth of the train wheel from the hour wheel 12 to the constellation gear 18 so as to be a value very close to the second) rotation, that is, 1.00027379 rotation. In the range of 12 to 73 teeth, which shows the best approximation of the number of teeth with approximate accuracy, the wheel pulley 12b on the drive side and the adjustment wheel can 14b have 3N and 61 teeth, and the adjustment gear on the driven side. The number of teeth of 14a and the constellation gear 18 is 5N and 73 (N is 4 or more 14
The following integer), and at this time the constellation gear 18 is 1.00027 per day
The annual cumulative error of the 397-rotating constellation display plate 2 is only 0.2 ° ahead of the apparent mean motion of the star. Wheel Cart 12 here
The reason why the combined cylindrical wheel is constituted by the cylindrical gear 12a and the cylindrical wheel pinion 12b is that the number of teeth of the cylindrical wheel pinion 12b can be selected without being restricted by the meshing condition with the Hino back wheel 13.

Further, by inserting the adjusting wheel 14 between the hour wheel 12 and the star wheel 18, the direction of rotation of the constellation display plate 2 fixed to the hour wheel 18 becomes the same right rotation as the hour hand 3 attached to the hour wheel 12. ,
Constellation display plate 2 where declination increases from the center of rotation toward the outer circumference
It matches the rotation condition of.

The operation at the time of initial adjustment will be described below.

First, pull out the crown 24 from the normal position 24a to the two-step pulling position 24c, adjust the hour hand 3 and the minute hand 4 to noon, and further perform the time difference correction. For example, in Tokyo, about 19 minutes from the 135 ° east longitude Since the time of Nanchu is early, it's morning
Set the hour hand 3 and minute hand 4 at 11:41.

Next, read the right ascension value of the right ascension numeral part 9c corresponding to the day and month scale 9d of the second constellation display part 8. For example, in the case of August 30, it is about 10 at the star time of 135 ° east longitude and noon. It should be 32 minutes.

Next, move crown 24 to the one-step pull position, and set crown 24 to the right,
In reverse rotation, the RA value of the constellation display plate 2 corresponding to the 12 o'clock position mark 6a 'indicating the south-central direction of the dial 6 shown in FIG. 1 is set to the above value, for example, 10 o'clock on August 30th. Match 32 minutes.

Finally, pull out the crown 24 again to the two-step pulling position 24c, adjust the hour hand 3 and the minute hand 4 by rotating the crown 24 forward and backward, and then push the crown 24 to start the second hand 5 and start the hour hand 3, Set the minute hand 4 and second hand 5 to the current time (average sun time). For example, as shown in Fig. 1, am on August 30th
In the case of Tokyo (longitude correction time difference + 19 minutes) at 10:09:39, the local sidereal time after adjustment should be approximately 9:00.

Further, in this embodiment, the pulling position 24 of the crown 24
Using the correction function of the constellation display plate 2 in b, if the standard latitude (35 ° north latitude) is read and the time difference between the current star time and the star time in the setting sun is read during the daytime, the remaining sunshine hours and If you read the stellar time difference from the state to the sunset,
In addition, after sunset, if you read the time difference between the star time when the sun position passes the horizon 6e and the star time that passes the twilight limit line 6i, the twilight duration is the hour hand 3, minute hand 4, in both cases above.
The second hand 5 is configured so that it can be read without stopping.

Further, in the present embodiment, the latitude used is 35 ° north latitude, and the constellation display plate is provided with a celestial sphere so that declination increases from the center of rotation toward the outer periphery, but an idler is installed between the wheel train from the hour wheel to the constellation gear. In addition to the specification that the direction of rotation of the constellation display plate is counterclockwise and the center of rotation of the constellation display plate is the north pole of the sky, and also in the case of different latitudes including the southern hemisphere, It is obvious that the same effect can be obtained by setting the rotation direction condition, the horizon line shape of the dial, and the mesolight line shape so as to meet the specifications.

Further, in the embodiment, the sun position is printed and displayed on the constellation display plate so that it can be read corresponding to the month and day. However, another method for substantially indicating the position, for example, one rotation per day concentric with the hour wheel, etc. If a line segment connecting the tip of the indicator needle and the correct sun position is printed on the constellation display board at appropriate intervals after providing the speed indicator needle,
Even if you do not know the date of the day, you can know the sun position, and if the sun position corresponding to the date is marked on the ecliptic on the constellation display board, you can also read the date, so as an annual calendar It is also possible to use a configuration that can be used, and it can be said that it is a range that can be modified based on a 24-hour clock that has an hour hand once a day. Further, in this embodiment, since the dial has the two large display windows of the constellation display window and the twilight identification window, the exposed area of the constellation display board is large and a twilight display watch having a beautiful constellation display function can be obtained. .

〔The invention's effect〕

As is clear from the above description, according to the present invention, since a timepiece with a twilight display capable of accurately knowing the time of twilight can be obtained with a simple train wheel configuration, on any day, for a few minutes even after sunset. Since it is still bright, you can make plans such as outdoor activities without lighting. Also, by rotating the display panel from the outside, you can read the twilight duration, sunshine duration, and remaining sunshine duration by knowing the sunset time and twilight end time on any day, and astronomical observation. Of course, it is possible to realize a convenient clock that can be widely used in daily life, such as outdoor sports such as mountain climbing, and guidelines for the time of agricultural work.

[Brief description of drawings]

1 to 5 show an embodiment of the present invention, FIG. 1 is a plan view of a timepiece with twilight display, and FIG. 2 is a sectional view showing a main part of a train wheel mechanism of the timepiece with twilight display. FIG. 3 is a partial plan view showing the outline of the train wheel of the twilight display timepiece, FIG. 4 is a plan view of the constellation display plate, and FIG. 5 is a bottom view of the twilight display timepiece. 2 ... constellation display board, 2b ... ecliptic, 2e ... break indicating the sun position on the ecliptic, 2f ... month number indicating the position of the sun at the beginning of the ecliptic, 3 ... hour hand, 6 ... dial , 6c …… twilight identification window, 6e …… horizon, 6i …… twilight limit line, 12 …… cylinder wheel, 14
…… Adjustment car, 18 …… constellation gear.

Claims (1)

[Claims] 1. An hour wheel holding an hour hand, a display plate that makes one rotation per star day, a display wheel integrated with the display plate, and an external operation unit that rotates the display wheel. In the timepiece, an adjusting wheel for transmitting the rotation of the hour wheel so that the display wheel makes one rotation on one star day is provided, and the display plate indicates the star position and the sun position corresponding to the moon and day. By forming the sun position display portion to be substantially displayed, forming the horizon and the twilight limit line displayed by holes or printing on the dial or windshield, and rotating the display plate by the external operation unit, A twilight display watch characterized by being configured so that the twilight time can be known by displaying the sunset time and twilight end time of a desired day.