Patent ID: 8413554

Claim:
A unidirectional ratchet wrench comprising: a wrench body comprising a handle; and a head being formed on and protruding from the handle and having two edges; a stationary jaw formed on and protruding from one edge of the head and having an undulating surface and having a limiting protrusion formed on and protruding from a position adjacent to a distal end of the undulating surface of the stationary jaw; a supporting protrusion formed on the undulating surface of the stationary jaw; an engaging protrusion formed on the undulating surface of the stationary jaw between the limiting protrusion and the supporting protrusion; a first recess with a curved bottom defined between the limiting protrusion and the engaging protrusion; and a second recess with a curved bottom defined between the engaging protrusion and the supporting protrusion; and a ratchet jaw formed on and protruding from other edge of the head to form a space between the ratchet jaw and the stationary jaw for holding a tool head and having a distal end away from the handle; an inner surface; two side surfaces; and an arced slot formed in the inner surface of the ratchet jaw and having an inner surface that has a curvature; and a ratcheting assembly mounted in the arced slot and comprising an engaging tab movably mounted in the arced slot, being arced and comprising an inner surface; an outer surface abutting the inner surface of the arced slot; a tip end away from the distal end of the ratchet jaw and extending out of the arced slot and into the space between the ratchet jaw and the stationary jaw; a blunt end being adjacent to the distal end of the ratchet jaw, extending out of the arced slot and into the space between the ratchet jaw and the stationary jaw and having a width wider than that of the tip end; and a guide hole formed through the engaging tab, being curved and having a curvature having a center same as that of the curvature of the inner surface of the arced slot; a drive end; and a non-drive end disposed near the blunt end and disposed opposite to the drive end; and a pin mounted movably through the guide hole and securely in the side surfaces of the ratchet jaw, wherein the engaging protrusion having a contacting point adapted for abutting with a flat on the tool head; the supporting protrusion having a contacting point adapted for abutting with another flat on the tool head; and the contacting points on the engaging protrusion and the supporting protrusion have an included angle of 60 degree.