Power indicator device of a thermoelectric generator of a watch

A power indicator device (1) of a thermoelectric generator (10) of a watch (30), the indicator device (1) comprising a first gas fluid reservoir (2), a second gas fluid reservoir (3), and at least one tubular conduit (4) connecting the two reservoirs (2, 3), the first reservoir (2) being intended to be placed on an upper surface of the thermoelectric generator (10) in a watch case (30), while the second reservoir (3) is intended to be placed on a lower surface of the thermoelectric generator (10) in contact with the back of a watch case (30),

• wherein the tubular conduit (4) is of the capillary type and comprises in an intermediate portion (9) a liquid forming a barrier to the gas fluid of the two reservoirs (2, 3) and allowing in a display portion (24) in the intermediate portion (9), to provide an indication of the power of the generator by measuring the temperature difference of the two reservoirs (2, 3), the display portion (24) being intended to be disposed in the watch case (30) to be visible from the outside of the watch case (30).