Abstract: A watch comprising civil time display means (12, 16), solar time display means (13, 18) and means of correction (24, 34, 36) of the displays. In this watch, the means of correction are arranged in such a way as to allow the relative desynchronization of the civil time and solar time display means. It furthermore comprises means for displaying this desynchronization (20, 22).

Abstract: The invention concerns a watch equipped with means for determining a location longitude and a device for determining the sun's altitude above the horizon. Said watch comprises a mobile element (16) doing one full rotation in 12 hours and bearing a hour hand (24), and a dial (32). It comprises for this purpose a rotating ring (44) for reading longitude, bearing an index mark (47) and, therefrom, a scale (45) in degrees, extending from 0° to 90° on either side of the index mark and covering the ring (44) over its whole periphery. Moreover, the dial (32) is provided with a circular scale (33) for selecting a time zone, with a median point (35) corresponding to the dial top point and a graduation from 0 to +6 hours or ?6 hours depending on the rotational direction.

Abstract: Apparatus for controlling shock/boundary-layer interactions created by a supersonic shock on a surface of a structure, includes a cavity formed in the structure and having an opening on the surface. A plate is attached to the surface and covers the opening. A plurality of flaps are formed on the plate and is operable to cooperatively close the opening in response to subsonic airflow condition over the flaps, and open the opening to permit airflow through the cavity in response to supersonic airflow conditions over the flaps.

Abstract: Apparatus for controlling shock/boundary-layer interactions created by a supersonic shock on a surface of a structure, includes a cavity formed in the structure and having an opening on the surface. A plate is attached to the surface and covers the opening. A plurality of flaps are formed on the plate and is operable to cooperatively close the opening in response to subsonic airflow condition over the flaps, and open the opening to permit airflow through the cavity in response to supersonic airflow conditions over the flaps.

Abstract: A passive transpiration system for controlling interaction between turbulent boundary layer air and an impinging shock during supersonic airflow by application of a panel including passively activated mesoflaps that direct air circulation through a cavity in response to supersonic airflow. The mesoscopic flaps are preferably arranged in a matrix on one side of a cavity. The flaps deflect to allow air to circulate through the cavity during supersonic airflow, thus controlling the interaction between boundary layer air and air from the impinging shockwave. The flaps open to varying degrees depending on the speed of the airflow. The preferred structure includes channel sidewalls arranged parallel to one another and open on one end, creating multiple cavities. The sidewalls are connected by struts. Rows of flap support beams are connected to the sidewalls. The flaps are connected on one end to the beams, enabling them to deflect over their remainder in response to aerodynamic pressures.

Abstract: The links, which are hinged together constituting the bracelet, comprise a core (2) formed from machinable metal and provided with hinges (14), sandwiched between two protection parts (4, 6). The protection parts are maintained in place by at least one stud (10) fixed to one of the protection parts (6) and extending through piercings (12, 13) formed respectively in the core (2) and in the other protection part (4), the stud (10) being retained in said piercings by a swaged rivet head at its distal end (10a). Two lateral portions (8) of one of the protection parts (6) extend opposite the lateral faces of the link.

Abstract: The "Isolated Combustion and Dilution Expansion (ICADE) Engine", is a piston/cylinder arrangement used primarily for the compression of air and the expansion of diluted hot combustion products. Fuel injection and rapid combustion take place inside a separate combustion chamber, using a near stoichiometric mixture. The combustion pressurization provides the pressure needed to accelerate the combustion products tangentially into the donut shaped cavity formed by the piston/cylinder clearance. There they establish a vortex which enhances rapid mixing, rapid cooling to quench NO.sub.x forming reactions and to temporarily store the kinetic energy of the combustion products to limit the combustion pressure peak acting on the piston surface. The tangential entry also permits detonation combustion without normal shock reflections on the piston surface, thus preventing "knock".

Abstract: The method of manufacture of this watch case consists in employing a material including at least 95% copper in its composition, the remainder being made up of elements adapted to increase the mechanical strength of the copper while avoiding the toxic elements beryllium and cadmium. Thanks to this material the watch case may be stamped out in a single operation, hardened, then covered with a protective layer deposited galvanically or by a PVD process.

Abstract: The watch case of this invention includes a caseband (2) made from sintered material and a back cover (10) secured to the caseband by means of at least two pins (12). Each pin passes through a first hole (14) provided in a first projection (16) formed in the caseband and two second holes (13, 15) provided respectively in two second projections (17, 18) formed in the back cover, said second projections being arranged respectively on either side of said first projection. Each pin being axially retained in its holes by the elastic effect provided by the seal when the caseband lies on the back cover.

Abstract: The watch case of this invention includes a caseband (1) hollowed out in the form of a vault (10). Such caseband includes first (5) and second (6) cylindrical support surfaces cooperating respectively with a crystal (2) and a back cover (3). Three blocks (7), unitary with the caseband, are arranged within the hollowed-out vaultlike space. Each block bears a projection (11) extending towards the movement (17) borne by the case, said projection having an upper snap (12) on which rests a flange (15) supporting the crystal and a lower snap (13) on which rests a casing ring (16) on which the back cover bears.

Abstract: Sapphire watch cover glass or crystal.The glass or crystal (18) comprises on a part of its upper face, a superficial layer (28) having an amorphous structure. This layer (28) makes it possible to increase the hardness of the glass or crystal in its exposed parts while reducing the risk of breakage of said glass or crystal.

Abstract: An exterior element for a wrist watch such as a case or bracelet at least partially formed from a composite material. Such material comprises an organic binder such as an acetal homopolymer and macroscopic particles of mineral substances which arrive flush with at least a portion of the visible surface of the element and cover the major part of said portion.

Abstract: The watch case of this inveniton includes means for fixing the crystal to the case having surfaces exposed at the exterior of the watch thus susceptible to being scratched. Such visible surfaces are protected by an armour formed essentially of a substrate made from a metallic carbide and a material covering the substrate such material having a hardness greater than 5000 HV.sub.0.25.

Abstract: The watch case has its body fashioned of hard metal of hardness preferably greater than 1400 Vickers. The body is overlaid by a two layer coating. The chemical composition of the two layers is identical and comprises the combination of a metal and an element whose atomic number is less than 9. The first layer is deposited by CVD and the second by PVD. If the metal is titanium and the element nitrogen there is obtained on the body of the scratch proof case a perfectly adhering hard coating of gold color.

Abstract: A timepiece containing, primarily, a first transparent element (1) visible from the outside of the piece, characterized in that this element has an adherent lining (2, 4) applied to at least part of its surface and assuring the attachment to that element of a decorative outer coating of hard material (3) and/or of a layer of high-temperature soldering material (5).

Abstract: In the manufacture of a watch case part comprising a glass and a middle having an opening for the glass, the following operations are carried out: first, a metallic coating is deposited on a peripheral portion of the glass, then one or more elements are formed on the coating by moulding a molten material having an affinity for the metal forming the coating, whereupon the glass is secured to the middle through the intermediary of the fastening element. The fastening element may consist of a heel extending around the periphery of the glass or of fastening studs extending at right angles to the plane of the glass. In some cases the fastening element may also act as sealing element.

Abstract: A watch case is described comprising a glass soldered to a metal part. The area of the glass having to be soldered to the metal part is provided with a coating which includes at least an outer layer made of the same material as the metal part.