Double lock rotatable snowboard boot binding

A snowboard boot binding attachment device for securing a snowboard boot binding to a snowboard and for permitting angular adjustment of the snowboard boot binding relative to the snowboard, comprising:

• a pair of rigid plates including a circular base plate adapted to be secured to the snowboard and a rotatable plate for receiving the snowboard boot binding to be secured thereto, the rotatable plate being positioned above the base plate and being rotatably connected to the base plate;
• and
• a locking assembly for locking the rotatable plate in selected positions of angular adjustment relative to the base plate and for selectively maintaining the rotatable plate in either a locked mode, in which the rotatable plate is prevented from rotating relative to the base plate or a released mode, in which the rotatable plate is free to rotate relative to the base plate, the locking assembly including a lock ring formed by a plurality of locking holes extending through a circumferential portion of the base plate, an opening extending through the rotatable plate and alignable with the locking holes in the selected positions of angular adjustment, a locking base attached to the rotatable plate, the locking base having a vertical opening extending therethrough which is aligned with the opening in the rotatable plate, the vertical opening being formed by an interior surface which is threaded along an upper portion and has downwardly and inwardly tapering walls along a lower portion, a locking shaft, and an externally threaded sleeve having binding tabs depending therefrom, the externally threaded sleeve being slidably fitted over the locking shaft and being nonrotatable relative to the locking shaft, the externally threaded sleeve being threadedly received within the vertical opening of the locking base with the locking shaft extending through the externally threaded shaft and the rotatable plate, the externally threaded sleeve adapted to be rotated relative to the locking base upon rotation of the locking shaft for permitting the locking shaft to assume either a locked position, in which the binding tabs of the externally threaded sleeve are forced against the locking shaft by the tapering walls of the locking base when the externally threaded sleeve is threaded further downwardly into the vertical opening for securely locking the locking shaft in a selected vertical position relative to the locking base, or a released position in which the binding tabs are separated from the locking shaft for permitting movement of the locking shaft relative to the locking base, the rotatable plate being in the locked mode when the locking shaft is in a lowered position with a lower portion of the locking shaft received within a selected one of the locking holes in the base plate and the locking shaft is in the locked position for preventing rotation of the rotatable plate relative to the base plate, and the rotatable plate being in the released mode when the the locking shaft is in a raised position with the lower portion of the locking shaft disengaged from the locking holes and the locking shaft is in the locked position for permitting rotation of the rotatable plate relative to the base plate, the mode of the rotatable plate being changeable when the locking shaft is in the released position.