FR2684775A1 - Device for indicating the times of the tides - Google Patents

Abstract

A device for indicating the times of the tides comprises: - a first indicator of periods of spring tides, neap tides and intermediate periods comprising a first element (23) rotating at a rate of one revolution in 59 days, this element including a graduation (28) passing in front of a pointer or behind a fixed window (29), - a second indicator of the time remaining before a high tide or a low tide depending on the period of spring tides, neap tides and intermediate periods comprising a second element (60) rotating at a rate of one revolution in 12 hours 25 minutes and 14 seconds, this element including at least one plurality of adjacent marks (66), each corresponding to one period, and passing in front of a concentric circular time graduation (56).

Description

INDICATOR DEVICE
TIDE SCHEDULE
The present invention relates to a device indicating the time of the next rising or falling tide and / or the time remaining before such an event, and this at any time of the year and regardless of where the observer is locates. Such a device finds all its usefulness for navigators wishing to calculate the optimum moment to enter a port, that is to say at high tide; or for people wishing to collect shells at low tide in the intercotidal zone.

 However, the tide cycle, with an average duration of 12 hours 25 minutes and 14 seconds, is in fact disturbed by other factors such as the moon phases, the equinoxes, the local relief and the cotidal wave. The combination of these influences can lead to errors of appreciation of more or less I hour compared to the lunar cycle taken as the only reference, and in the worst case up to a delay of 8 hours depending on the places of observation , while the average period between a high tide and a low tide is only about 6 hours.

A device indicating the tide schedule, described in application FR 91.03147 filed by the present applicant, more particularly comprises a first indicator rotating at the rate of a revolution in 59 days before a graduation calibrated according to the periods of White Water, Dead waters and intermediate periods; and a second indicator rotating at the rate of a revolution in 12 hours 25 minutes and 14 seconds in front of a circular graphic assembly representing the time remaining before a Full Sea or a
Bass Mer according to the period of Vives Eaux, Mortes
Waters and intermediate period.

This device, once correctly set, effectively gives indications of the timetable or the time remaining before the tides with greatly increased precision compared to previous devices based solely on the lunar rhythm. The object of the present invention is a new embodiment making it possible to carry out the correction varying as a function of the momentary period of Vives Eaux,
Dead Water or intermediate period in an even simpler and therefore easier way.

This goal is achieved thanks to a device indicating the tide schedule, the first indicator of the periods of White Water, Dead Water and intermediate periods includes a first rotating element at the rate of a revolution in 59 days, this element comprising a graduation passing in front of an index or behind a fixed window; and whose second indicator of the time remaining before a Full Sea or a
Bass Mer according to the period of Vives Eaux, Mortes
Waters and intermediate periods comprises a second element rotating at the rate of one revolution in 12 hours 25 minutes and 14 seconds, this element comprising at least a plurality of adjacent marks, each corresponding to a period, and passing in front of a concentric circular hourly graduation.

 In this embodiment, the momentary period of Vives Eaux, Mortes Eaux or intermediate periods is identified by a possibly colored division of the graduation passing inside a reading window, and the desired final reading is then easily done by reading the position of the corresponding marker, advantageously of the same color as the previous division, in front of a concentric circular hourly graduation.

According to a preferred embodiment of the invention, the second indicator of the time remaining before a Full Sea or a Low Sea according to the period of White Water, Dead Water and intermediate periods comprises two concentric hourly graduations denominated in the same direction . The second rotating element is in the form of a crown produced on a transparent disc concentric with the graduations, the inner periphery of the crown being circular with a radius slightly greater than that of the internal graduation relative to the time remaining before a Low Seas this circumference interior being completed by a first series of adjacent landmarks corresponding respectively to the periods of Vives Eaux à Mortes Eaux, the outer periphery of the crown being circular eccentric so that its largest radius corresponds to that of the external graduation relative to the remaining time before a High Sea, this outer circumference is also completed by a second series of adjacent landmarks corresponding respectively to the White Water periods at
Dead waters.

In this embodiment, the identical color markers located on the outer and inner periphery of the crown simultaneously and obviously indicate the corrected remanent time until the
Full Sea and the following Low Sea.

 Preferably, the two concentric hourly graduations are substantially in phase, and the two series of marks are then substantially symmetrical with respect to the center of the transparent disc. The outer periphery of this crown then also has two notches that are substantially symmetrical with respect to the center of the transparent disc and halfway between the series of marks to reveal an indication of mimare.

 Also usefully, the external hourly graduation can be carried out on a mobile crown allowing the hourly rise and fall ratio of the tide to be modified as a function of the desired location as indicated by markers.

 The device according to the invention is associated in a wristwatch with a second timepiece movement rotating on a solar rhythm, the upper case of which is folded over the lower case of the device by rotation around a hinge. The back of the upper case of the second movement has an engraved table indicating the correction depending on the location due to the cotidal wave.

The invention will be better understood from the study of embodiments taken by way of nonlimiting examples and described by the following figures.
FIG. 1 is a perspective view of a wristwatch, the upper case of which contains the first indicator,
FIG. 2 illustrates the detail of the graduation in terms of Vives Eaux / Mortes Eaux of the first indicator,
FIG. 3 illustrates the second indicator of the device according to the invention housed in the lower case of the wristwatch,
FIG. 1 illustrates a wristwatch 10 comprising a lower case to which the bracelet is attached and an upper case 20 which is folded over the lower case by rotation around a hinge 15. This upper case 20 is held in position by example by a hook (not shown) located on the opposite side of the hinge 15.

 The upper case 20 contains a conventional watch, that is to say a solar clock movement indicating the time, this movement being completed by a lunar phase indicator 25. As illustrated in FIG. 2, this lunar phase indicator 25 comprises a disc 23 on which two opposite moons are represented, this disc rotating at the rate of one revolution in 59 days behind a window whose lower edges have two adjacent arcs. A new moon corresponds to a representation appearing on the left part of the window, a full moon corresponds to the representation located in the center of the window and a last quarter corresponds to a representation partially hidden by the right part of the window.

According to the invention, this upper casing also has a window 29, otherwise called a window, behind which the graduated outer crown 28 of the disc 23 passes. For a better reading, this graduation calibrated as a function of the Vivid Waters and Dead
Waters is produced in sectors of different colors, for example black for the coefficient of 120 corresponding to Vives Eaux, blue for the following coefficient of 90, red for the coefficient of 75, green for the coefficient of 60 and yellow for the coefficient 45 corresponding to the Dead Waters.

Vives Eaux means a period during which the difference in water level between a low tide and a high tide is at its maximum, and Mortes Eaux means a period during which this difference in water level is at its minimum. For example, in the port of Le Havre in January, the sea level is at 7.75 m at high tide for 1.80 m at low tide during the White Water period and only at a level of 6.40 m at tide high for 3.75 m at low tide in Dead Water. As can be seen from Figure 2, the White Water periods correspond substantially to the periods of the full moon and new moon while the Dead Water periods correspond to the rising and falling quarters. In fact, the correction evolution in the Dead Water to Live Water cycle turns out to be faster than in the cycle
Vives Eaux vers Mortes Eaux. For better accuracy, the period between a Vives Eaux and a Mortes
Waters is itself divided into five sub-periods corresponding, on the graduation, to sectors of different colors.

 With reference to FIG. 3, the device comprises a second watch movement turning a transparent disc 60 completed on its periphery with a dark crown 62 provided with internal 66 and external 67 marks in front of two concentric circular graduations of 12 hours and 20 minutes each, one internal 56 for the determination of the time remaining until a low tide or "BM", the other external 57 for the determination of the time remaining before a high tide "PM".

The external graduation 57 is in fact carried out on a mobile crown making it possible to modify the hourly ratio between a rising or falling phase of the sea according to the places referenced by the indices 55 A, B,
C and D. For example, for a place referenced D, the period of descent of the water is approximately 7 hours 1,2 while the period of rise of the waters is reduced to only 4 1/2 hours, which is compare to an average of about 6 hours 13 minutes.

 The internal diameter of the crown 62 is a little larger than that of the internal graduation 66, while the external periphery of this same crown is circular but eccentric so that the maximum radius is slightly less than the radius of the external graduation 67 The internal periphery of this crown 62 is lined, in the zone of lesser thickness, with a series of marks 66 oriented inwards for the reading of the time remaining before the next Low Sea depending on whether it is in the Vivid period. Waters or Dead Waters as indicated directly by the color mark corresponding to the color then appearing in window 29 of the upper case. Similarly, a second series of multicolored marks 67 for reading the time remaining before the next Full Sea is produced on the thickest portion of the outer periphery, therefore opposite the first.

 Before using the device, like any watch movement, it should be set beforehand. The adjustment of the solar and lunar movement contained in the upper housing 20 is done in a known manner.

 It is then necessary to calibrate the movement of the tide on the annual average according to the process described in application FR 91.03147. A second calibration consists in adjusting the position of the mobile crown as a function of the hourly ratio between the rising and falling periods depending, for a given place, on its local relief, and this by turning this mobile crown carrying the external graduation 57 to bring the point PM opposite index 55: A, B, C or D designating the category to which the observation site belongs.

 Thus calibrated, the device according to the invention is available for use. As we have been able to understand on reading the description above, the observer first identifies the color visible in the window 29 of the upper case, a color representative of the Vives Eaux, Mortes Eaux or intermediate phase. Then, by discovering the second movement, it reads directly by means of the two corresponding color markers, respectively internal and external, the remaining times before the following events: high or low tide. By simple addition with the current time read on watch 22, he can easily deduce the exact moment of this next event.

 Many other variants can be made to this device in the context of this invention.

Claims (4)

1. Tide hour indicator device comprising a clock movement to rotate an indicator in front of a graduated dial, characterized in that it comprises  - a first indicator of Vivid periods Waters, Dead Waters and intermediate periods comprising a first element (23) rotating at the rate of one revolution in 59 days, this element comprising a graduation (28) passing in front of an index or behind a fixed window (29),  - a second indicator of the time remaining before a Full Sea or a Low Sea according to the period of White Water, Dead Water and intermediate periods comprising a second element (60) rotating at the rate of a revolution in 12 hours 25 minutes and 14 seconds, this element comprising at least a plurality of adjacent marks (66), each corresponding to a period, and passing in front of a concentric circular graduation (56). 2. Device according to claim 1, characterized in that the second indicator comprises two graduations (56,57) concentric hours denominated in the same direction, the second rotating element being in the form of a crown (62) produced on a transparent disc (60) concentric with the graduations, the inner periphery of the crown being circular with a radius slightly greater than that of the internal graduation (56) relating to the time remaining before a Bass Sea, this inner periphery being completed by a first series of adjacent landmarks (66) corresponding respectively to the periods of Vives Eaux to Mortes Eaux; the outer periphery of the crown (62) being eccentric circular so that its largest radius corresponds to that of the external graduation (57) relating to the time remaining before a High Sea, this outer periphery also being completed with a second series adjacent marks (62) corresponding respectively to the periods of White Water to Dead Water. 3. Device according to claim 2, characterized in that the two graduations (56,57) concentric hours are substantially in phase, and in that the two series of marks (66,67) are substantially symmetrical with respect to the center of the disc transparent (60). 4. Device according to claim 3, characterized in that the outer periphery of the crown (62) has two recesses (68) substantially symmetrical with respect to the center of the transparent disc (60) and halfway between the series of marks ( 66.67) to reveal an indication of mid-tide.