초록 ▼

The wristwatch includes in its case a resistive piezo-electric pressure and temperature sensor ( 26 ) exposed to a pressure chamber ( 42 ) communicating with the outside environment, for measuring ambient pressure. In order to provide individual calibration as a function of temperature followed by a

The wristwatch includes in its case a resistive piezo-electric pressure and temperature sensor ( 26 ) exposed to a pressure chamber ( 42 ) communicating with the outside environment, for measuring ambient pressure. In order to provide individual calibration as a function of temperature followed by a permanent correction of the sensor pressure signals, the latter is fixed to the lower surface of a printed circuit board ( 30 ) bearing the electronic circuits ( 35 ) processing the sensor signals. The calibration parameters are stored in a non-volatile memory ( 36 ) of said circuits. A rigid and sealed separating wall ( 43 ) forms an internal bottom separating the pressure chamber ( 42 ) from the watch sealed part.

대표청구항 ▼

1. An electronic watch providing a barometer or altitude reading based on ambient pressure and including:a case including a middle part and a back cover, the interior of said case being divided by separating means into a sealed part and a pressure chamber which communicates with the outside of said

1. An electronic watch providing a barometer or altitude reading based on ambient pressure and including:a case including a middle part and a back cover, the interior of said case being divided by separating means into a sealed part and a pressure chamber which communicates with the outside of said case so as to receive the ambient pressure, said separating means including a separating wall extending substantially parallel to said back cover,an electric power source,a pressure sensor having one side exposed to the pressure prevailing in said pressure chamber,display means for supplying a time indication and said barometer or altitude reading, anda printed circuit board disposed in said sealed part of said case and provided with time-keeping circuits and electronic circuits arranged to receive and process an output signal from said pressure sensor and to control said barometer or altitude reading display means,wherein said pressure sensor is mounted on a back surface of said printed circuit board, to which it is directly connected by electric connections, said separating wall having an opening in which said sensor is placed. 2. A watch according to claim 1, wherein temperature measuring means are installed on said printed circuit board and wherein said electronic circuits include a non-volatile memory in which are stored individual calibrating parameters of said pressure sensor as a function of temperature. 3. A watch according to claim 2, wherein said sensor is a pressure and temperature sensor of the piezo-resistive type including resistors connected in a Wheatstone bridge whose resistance varies only as a function of temperature, whereas pressure variations create an unbalance in said bridge. 4. A watch according to claim 1, wherein said display means include analogue display means. 5. A watch according to claim 4, wherein said printed circuit board is rigid and constitutes a plate supporting, on the opposite side to said pressure sensor, at least one electric motor for said analogue display means. 6. A watch according to claim 1, wherein said separating wall is connected to the middle part of said case in a sealed manner along its periphery. 7. A watch according to claim 6, wherein said opening is located proximate to said periphery of said separating wall. 8. A watch according to claim 7, wherein, outside a support surface encompassing said opening and abutting against said printed circuit board, a gap allowing said separating wall to bend is arranged between said separating wall and said printed circuit board. 9. A watch according to claim 6, further including sealing means disposed between said separating wall and said printed circuit board, and arranged in or around said opening. 10. A watch according to claim 9, wherein a ring surrounding said pressure sensor laterally is bonded to said printed circuit board and extends into said opening of said separating wall, said sealing means including a sealing gasket inserted between said ring and said separating wall. 11. A watch according to claim 10, wherein said sealing gasket is associated with a sealed membrane which separates said pressure sensor from said pressure chamber. 12. A watch according to claim 6, wherein said pressure chamber extends between said separating wall and said back cover. 13. A watch according to claim 12, including an electro-acoustic transducer arranged to transmit sounds into said pressure chamber. 14. An electronic watch providing a barometer or altitude reading based on ambient pressure and including:a case including a middle part, a crystal on a front side of the watch, and a back cover on a back side of the watch, the interior of said case being divided by separating means into a sealed part and a pressure chamber which communicates with the outside of said case so as to receive the ambient pressure,an electric power source,a pressure sensor having one side exposed to the pressure prevailing in said pressure chamber,display means for supplyin g a time indication and said barometer or altitude reading, anda printed circuit board disposed in said sealed part of said case and provided with time-keeping circuits and electronic circuits arranged to receive and process an output signal from said pressure sensor and to control said barometer or altitude reading display means,wherein said pressure sensor is mounted on a back surface of said printed circuit board, to which it is directly connected by electric connections, said separating means including a separating wall having an opening in which said sensor is placed.