Hinge structure having leaf portions with adjustable clamping force arm

A hinge structure adapted to couple a shaft of a pintle, comprising:

• a barrel portion having a first edge and a second edge opposite to the first edge, and the barrel portion being formed by extending from the first edge in a circular direction to the second edge, and accordingly, having a substantially C-shaped cross section;
• a first leaf portion having a first root end and a first free end;
• the first leaf portion being connected at the first root end to the first edge of the barrel portion with the first free end extended away from the first edge of the barrel portion in a direction defined by a horizontal datum plane;
• a second leaf portion having a second root end and a second free end;
• the second leaf portion being connected at the second root end to the second edge of the barrel portion with the second free end extended away from the second edge of the barrel portion in a direction defined by the horizontal datum plane;
• and
• at least one leaf locating element mounted to a position near the first free end of the first leaf portion and the second free end of the second leaf portion, so that the first and the second free end are closely adjacent to and tightly bound to each other by the at least one leaf locating element;
• and the leaf locating element also functioning as a fulcrum, so that a clamping force arm section is defined between the fulcrum and the first root of the first leaf portion, and between the fulcrum and the second root of the second leaf portion;
• and
• wherein the shaft of the pintle is rotatably received in the barrel portion and subjected to a compression from the clamping force arm sections of the first and the second leaf portion, such that a predetermined rolling friction is existed between the shaft and the barrel portion.