Patent ID: 8312869

Claim:
An underwater shotgun of the crossbow type, that includes: a butt ( 1 ) with a mechanism for locking the rear end of an arrow ( 3 ) and a device for releasing the said arrow ( 3 ), a longitudinal arrow support element ( 2 ), elastic propulsion means with at least two lateral elastic cords ( 8 ), one end of which is designed to be hooked into at least one notch ( 17 ) in the rear part of the arrow ( 3 ), and a device for stretching the lateral elastic cords ( 8 ) including: a cocking base ( 18 ) fixed onto the longitudinal arrow support element ( 2 ) and with fixing elements ( 18 - 1 , 18 - 2 ) intended to receive the first ends of the lateral elastic cords ( 8 ); and a mobile head part ( 11 ) with thrust arms ( 15 ) positioned laterally on the mobile head part ( 11 ), the mobile head part ( 11 ) being designed to slide along the length of the arrow support element ( 2 ) under the action of a system for moving the mobile head part ( 11 ) between: a rear position (A 1 ) which, after passing around the thrust arms ( 15 ), allows the second ends of the elastic cords ( 8 ) fixed at the cocking base ( 18 ) to be placed without tension in the notch of the arrow ( 3 ), and a forward position (A 2 ) in which, when they are hooked into the notch ( 17 ) of the arrow ( 3 ), the elastic cords ( 8 ) are stretched to the maximum by a stretching movement effected, during the movement of the mobile head part ( 11 ), at an intermediate part of the elastic cords ( 8 ) passing around the thrust arms ( 15 ).