Adjustable tourniquet

An adjustable tourniquet, comprising a first component, a second component, a third component and a band for encircling human body, wherein one end of the first component has an axle for fixing the band and the other end has a buckling trough with at least an engaging element, and two ends of the axle respectively have a ratchet, the second component which is covered on the first component at least includes a driving element rejecting to the ratchet, and the third component has a buckling element at one end thereof for coupling with the engaging element, and the other end is an opening with a pressing shaft for fixing the band, and wherein the engaging element, the rejecting element and the driving element all have an elastic element for providing a recovering strength, characterized in that:

• the axle is a solid axle formed by a semicircular axle being clamped by an axial cover, and two ends of the axle are respectively connected with a connecting axle for penetrating the second component, so that the second component is capable of having a movement relative to the first component by taking the axle as the axial center;
• the ratchet includes an inner ratchet surface for rejecting to the rejecting element, and an outer ratchet surface for rejecting to the driving element, and the teeth of the inner and outer ratchet surfaces are respectively bent toward the same direct and the arranging directions of the inner and outer ratchet surfaces are perpendicular to each other;
• and
• through the rejecting element of the first component and the driving element of the second component simultaneously reject to the inner and the outer ratchet surfaces, when the second component have a movement by taking the axle as the axial center, the driving element drives the ratchet, so as to turn the axle in one direction, thereby rolling up and tightening the band.