Watch including an arrangement indicating the magnetic north

• US 5,550,794 A
• Filed: 07/20/1995
• Issued: 08/27/1996
• Est. Priority Date: 07/26/1994
• Status: Expired due to Term

• Current Assignee: Asulab SA (The Swatch Group AG)
• Original Assignee: Asulab SA (The Swatch Group AG)
• Inventors: Born, Jean-Jacques, Bornand, Etienne
• Primary Examiner(s): Miska, Vit W.
• Application Number:
  US08/504,580
• Time in Patent Office: 404 Days
• Field of Search: 368/10, 368/11, 368/14, 368/15, 368/20, 33/271, 33/355
• US Class Current: 368/11
• CPC Class Codes: G04B 47/065 with a compass compasses G01C17/00

Abstract

A watch including an arrangement (14) indicating the terrestrial magnetic north. Such terrestrial magnetic north indicating arrangement is fitted into the watch case (32) in a lateral peripheral region of the horological movement (2). Specifically, the terrestrial magnetic north indicating arrangement comprises a permanent magnet (16) mounted on a shaft (18) and a direction indicator (24) fixed to such shaft. In accordance with three specific embodiments, the watch according to the invention enables, firstly, indication of the north direction, secondly, any direction whatsoever permitting the user to follow a predetermined direction and, thirdly, the direction of Mecca from at least one place on the terrestrial globe where such user is located.

Claims

1. A watch comprising an horological movement, a case within which said horological movement is fitted, and means for indicating the terrestrial magnetic north also fitted within said case;

said terrestrial north indicating means comprising a bipolar permanent magnet mounted on a shaft defining a rotation axis, and a direction indicator rigidly fixed to said permanent magnet and made of a non-magnetic material;

said direction indicator having a longitudinal dimension which is perpendicular to said rotation axis and which defines the direction indicated by said direction indicator;

said permanent magnet exhibiting a radial magnetization defining a magnetic axis which is substantially perpendicular to said rotation axis and which is located within a peripheral region of said case, said longitudinal dimension of said direction indicator being eccentric relative to said rotation axis, said direction indicator having a rotational movement which is limited so that a larger longitudinal part of said direction indicator measured from said rotation axis and partially defining said longitudinal dimension is located in a circular sector oriented substantially in a direction of the center of said watch relative to said rotation axis.

2. A watch as set forth in claim 1, wherein said direction indicator is located between a dial and a crystal of said watch, and said permanent magnet is located between said dial and a back cover of the watch.

3. A watch as set forth in claim 1, wherein said permanent magnet is located in a lateral peripheral region exterior to said horological movement.

4. A watch as set forth in claim 1, wherein said permanent magnet is located in a lateral peripheral region within said horological movement, said shaft carrying said permanent magnet having two pivots respectively mounted in two bearings fitted into said horological movement.

5. A watch as set forth in claim 1, comprising a power cell, said permanent magnet being located in a region of said case which, relative to a central axis of said horological movement, is opposite the region in which said power cell is localized.

6. A watch comprising an horological movement with magnetic masses, a case within which such horological movement is fitted, and means for indicating the terrestrial magnetic north also fitted within said case;

said terrestrial north indicating means comprising a bipolar permanent magnet mounted on a shaft defining a first rotation axis and a direction indicator rigidly fixed to said permanent magnet;

said permanent magnet exhibiting a radial magnetization defining a magnetic axis substantially perpendicular to said first rotation axis, said permanent magnet being located within a lateral region peripheral to said horological movement, said direction indicator defining a longitudinal axis and being associated with a positioning reference marker along which said longitudinal axis is adapted to align itself, said permanent magnet magnetic axis and said direction indicator longitudinal axis exhibiting an angular separation having a value which is a function of said magnetic masses and of the position of said positioning reference marker relative to said first rotation axis, said value being determined in a manner such that said direction indicator indicates precisely the direction of the terrestrial magnetic north when its longitudinal axis is aligned on said positioning reference marker.

7. A watch as set forth in claim 6, comprising first graduations associated with said direction indicator, such graduations enabling the identification of at least the four cardinal compass points.

8. A watch as set forth in claim 7, wherein the direction defined in the general plane of the watch by said first rotation axis and said positioning reference marker corresponds to the north-south direction of said first graduations.

9. A watch as set forth in claim 6, serving to indicate the direction of Mecca, comprising means for indicating the direction of Mecca capable of undergoing a rotation around a second rotation axis perpendicular to the general plane of the watch, such second rotation axis defining a point representative of the geographical position of Mecca projected onto said general plane of the watch, said watch having at least one angular reference marker representative of a place or a region of Earth onto which a direction reference marker belonging to said means for indicating the direction of Mecca is capable of aligning itself, the direction of Mecca being provided by such direction reference marker whenever the latter is aligned on said angular reference marker corresponding to the place where the user of said watch is located and said longitudinal axis of said direction indicator is aligned on said positioning reference marker.

10. A watch as set forth in claim 9, having a set of angular reference markers corresponding to a set of cities and onto each of which said direction reference marker is adapted to be aligned, such angular reference markers being laid out around said second rotation axis.

11. A watch as set forth in claim 7, said first graduations being laid out on an element of said case, such case being rotatably mounted on a support fixedly coupled to a bracelet of such watch, said case being capable of rotation relative to said support so as to position any division whatsoever of said graduations in the 12 o'"'"'clock position of said watch.

12. A watch as et forth in claim 6, comprising second graduations defining a scale of magnetic declination, such second graduations being associated with said direction indicator in a manner such that said longitudinal axis of such direction indicator may align itself on any division whatsoever of such second graduations.