Device for locking the rotatable bezel of watches, especially underwater watches, and for rendering the winding button watertight

A device for application to a watch having a casing, a bezel rotatably coupled to the casing, a movement located inside the casing, a rewinding and resetting button located external to the casing, and a winding shaft coupled to the movement and the rewinding and resetting button and extending through a passage in the casing, the device comprising:

• a plastic washer contacting a flat surface of the rewinding and resetting button and being coaxially disposed with the rewinding and resetting button, the plastic washer engaging knurling along an outer circumference of the bezel when the rewinding and resetting button is in a retracted position adjacent the casing so that the bezel is locked in place;
• a seal carried by the rewinding and resetting button so that the seal is compressed between the rewinding and resetting button and the casing when the rewinding and resetting button is in the retracted position thereby rendering the passage within the casing water-tight;
• and
• a pressure means coupled to the casing and movable between a first and a second position, the pressure means axially pressing the rewinding and resetting button when the pressure means is located in the first position so that the rewinding and resetting button is held in the retracted position, the pressure means permitting an outwards movement of the rewinding and resetting button to a rewinding and resetting position when the pressure means is located in the second position.