Ebauches S.a.

Eta Sa Fabriques D'ebauches

Claude Laesser

Rene Viennet

Eric Saurer

Jean Depery

Hubert Portmann

Fereydoun Gharadjedaghi

Roberto Zafferri

Yves Ruedin

Rene Meister

Gerard Piller

The components of a mechanical watch are mounted inside a supporting structure comprising a stack of transparent plates made of corundum, spinel or quartz. Some of the plates are formed with cut-outs which define in the assembled structure housings for accommodating said components.

Portable device including a visible mechanism

The display device comprises a cell having two levels, between two polarizers 1 and 7, the directions of polarization of which are at an angle of 120.degree. to each other. The two-level cell comprises two liquid crystal layers 5 and 6, each of which, in the rest condition, causes rotation of the plane of polarization of the light through 60.degree.. The orientation of the molecules of the input surface of the first layer 5 is parallel to the direction of polarization P1 of the first polarizer 1. The orientation of the molecules of the input surface of the second layer 6 is parallel to the orientation of the molecules on the output face of the first layer 5. The orientation of the molecules of the output surface of the second layer 6 is parallel to the direction of polarization P2 of the second polarizer 7. This construction provides a two-level cell which is clear if the two liquid crystal layers are both in the rest condition, and which is dark in all other situations, whether one or the other or both layers 5, 6 are energized.

Liquid crystal display device

An electromagnetic stepping motor has a stator with an armature having the shape of an isosceles trapezoid the base of which is interrupted by a central gap and which is provided with three pole faces. The rotor comprises a permanent magnet. The stator comprises two coils one of which is located between a pole face opposite said gap and one of the other two pole faces. The other coil is located between the pole face opposite said gap and the other of said other two pole faces. When a current passes through the coils, the rotor is subjected to magnetic fields having directions which are oblique to each other and which are symmetrical with respect to a diameter of the rotor. The sense of the coil currents determines the sense of the fields. The arrangement is such that one can create in the zone of the rotor a resultant magnetic field which can extend in any one of four different directions dependent on the sense of the currents passing through the coils. By appropriate commutation of the sense of each of the two coil currents, one can cause the resultant magnetic field to rotate in one direction or in the other, to drive the rotor in one or the other directional sense, but always in the same direction for a given field rotation. Thus, the rotor rotates always in the desired direction, even if a rotational step is missed or if the rotor makes one rotational step too many.

Electromagnetic motor rotatable in either direction

Driving device especially for a timepiece, constituted by a stepping motor the stator of which comprises a coil having a single winding and the rotor of which is constituted of a permanent magnet and of a control electronic circuit able to deliver pulses of current to the motor. The motor includes precise positioning magnets for its rotor which are active in the absence of the pulses. The electronic control circuit is arranged in such a way that the pulses are delivered in pairs, with opposed polarities in each pair, the order of succession of the polarities in a pair determining the sense of rotation of the rotor.

Driving device especially for a timepiece

Electro-optic passive display cell constituted by a layer of a mixture of a nematic liquid crystal having a positive dielectric anisotropy, an optically active compound and dichroic molecules. The inner faces of the plates of the cell are covered with alignment layers such that, in the area situated outside the display zones or segments, the layer of the mixture has a homeotropic structure in its whole thickness. Opposite the segments the cell is arranged in such a way that the layer of the mixture has a helicoidal structure so that incident light is absorbed in these zones when the segments are not activated and that the layer of the mixture is orientated according to a homeotropic structure under the action of an electric field. Thus, when the cell is at rest, all its segments are visible. The display is effected by 'cancelling' or 'effacing' the segments which must not appear, so that only the non activated segments remaining visible in dark on a clear or transparent background.

Electro-optic passive display cell

An electromechanical calendar timepiece has a date display provided by two indicators carrying the 'units' and tens data, respectively. The motor which drives these indicators can rotate at a normal speed or at a considerably higher speed. The units data comprise two consecutive figures '1' intended to display, respectively, the unit of the thirty-first of the months having thirty-one days and the first of each month, and one or the other of which displays the units of the eleventh and twenty-first of each month. The motor rotates at said higher speed on the one hand at the end of the months having less than thirty-one days and on the other hand twice each month, i.e. each time the '1' of the units data is displayed at the beginning of the second and the third decades.

Electromechanical calendar timepiece

An electronic timepiece indicates a change in one of the working parameters of the timepiece, such as the battery nearing its end of life, by changing a rest position of a user viewable indicating member. The timepiece includes a stepping motor driven by drive pulses produced from a timebase. The indicating member is rotated a certain amount by each step of the stepping motor and has two rest positions. The first indicates no change in the working parameter and the second indicates a change in the working parameter. The indicating member normally stops in the first rest position. A circuit responsive to a change in the working parameter causes an additional drive pulse to be applied to the motor, changing the normal stopping of the indicating member to the second rest position to indicate the changed working parameter.

Electro-mechanical watch

An electro-optic display device having a partially transparent display cell and a semi-transparent mirror located behind said cell and arranged to transmit light waves within a first wave length band and to reflect light waves within a second wave length band. An electro-optic component is located behind the semi-transparent mirror and operates in a third wave length band which overlaps at least partially the first wave length band. The electro-optical component may be a plurality of photo cells used for recharging an accumulator for the display device and/or a light source transmitted across a light plate of frosted or clear glass to illuminate the display cell. The display cell is illuminated by either the reflected light waves or the light waves emitted from the light source.

Electronic watch and display device for such watch

A rotatable member to be driven step-by-step having a set of grooves, each of the grooves having two circular portions offset from one another and joined by a connecting portion. A driving rotatable disc has a first protrusion, having a radius of trajectory equal to the radius of the circular portions, which engages the first circular portion without driving the rotatable member. The protrusion follows the first circular portion as it rotates until it reaches the connecting portion where it drives the rotatable member forward one step until the protrusion is aligned with the second circular portion. The protrusion then follows the second circular portion without moving the rotatable member. A second protrusion can be provided on the driving rotatable disc to follow a third circular portion of a different radius so the rotatable member is locked in position except when the first protrusion is in the connecting portion. Alternately, a fourth circular portion of equal radius to the first and second circular portions can be provided connecting the second circular portion with the first circular portion of the next groove.

Mechanism for driving, step-by-step, a rotatable member

An electro-optic passive display device displays information in dark characters on a light background during the day, and in light characters on a dark background during the night. The device has a polarizer, an electro-optic display cell, a quarter-wave plate, a chloesteric liquid crystal cell and an illuminator arranged in superposition on each other. These elements control the polarization of light transmitted through the device which polarization causes the changing of the displayed information from dark characters on a light background to light characters on a dark background.

Electro-optic passive display device

An electronic timepiece provides photo-electric cells disposed behind a passive electro-optic display cell for recharging a storage battery. The timepiece includes in its display a polarizer, a passive electro-optic device such as a liquid crystal, a quarter-wave plate, a cholesteric liquid crystal reflector and photo-electric cell arranged in superposition upon each other. Ambient light passing through the cholesteric reflector is used to energize the photo-electric cells which recharge the storage battery. Ambient light reflected by the cholesteric reflector is used to indicate the displayed information.

Electronic instrument

A light guiding member for an electro-optic display device. The member is generally plate-shaped with thickened edge portions, one such edge portion forming an enclosure for a light source. The thickened portions are coated with conductive tracks to provide electrical connection between a substrate and display cell of the device.

Electro-optic passive display device and method for its manufacture

An electro-optic display cell including oppositely-facing transparent plates forming the inner surface of a compartment containing an incandescent lamp for illumination of the cell. The compartment is completely enclosed and itself forms the enclosure for the lamp.

Passive electro-optic display cell and method for manufacturing it

A passive display cell is described on which a plurality of digits are located. The digits are composed of electrode segments opposite counter-electrodes. These are connected in a manner enabling reduction of the number of outputs. As described with respect to the embodiments, the digits are arranged in separate groups with a pair of counter-electrodes for each digit in one group being also connected to counter-electrodes of another digit in another group. A pattern of conductor leads are employed and located in a non-crossing manner to connect like electrode segments to provide a multiple digit display cell having a low number of outputs.

Growing community of inventors

La Chaux-de-Fonds, Switzerland

Claude Laesser