Abstract: A screwdriver includes a body, a ratchet wheel, two pawl members, two elastic members, a cover, and a catch plate. Thus, the cover can be removed from the body, so that the user can inspect and adjust connection between the pawl members and the ratchet wheel, thereby facilitating the user repairing the screwdriver. In addition, the catch plate stops movement of the ratchet wheel and the pawl members, thereby preventing the ratchet wheel, the pawl members and the elastic members from detaching from the body after the cover is removed from the body.

Abstract: The invention relates to a one-way driving control mechanism of a wrench, which comprises a wrench body, a spinner element, a diameter-variable grommet and a pawl. The head portion of the wrench body has a housing for placing a spinner element, a diameter-variable grommet and a pawl. The middle portion of the spinner element takes the shape of an elliptic cylinder. A diameter-variable grommet consisting of two movable separate segments is set around the circumference of the cylinder. The outside diameter of such a diameter-variable grommet is slightly smaller than the inside diameter of the housing. With twisting the wrench, the spinner element rotates relatively to the wrench body, and then the elliptic cylinder pushes the diameter-variable grommet outward, which make one segment of the grommet jam against the wall of the housing to get one-way fastening. As a result, such a wrench is capable of achieving the virtues of simplifying mechanism and increasing torque.

Abstract: A ratchet wrench is provided that includes a link control structure in which the control rod slides smoothly in the D-head to control the ball that locks the joint with a socket or releases the joint. A new bolting joint structure between the D-head and the reversing disc is provided that consists of a straight segment at the front portion, as a guiding section, and a conic segment at the back portion, as a securing section of the threaded trunk, so that the bolt can be located at any desired position for adjustment, without the possibility of loosening. The reversing disc has a curved circular groove formed in the top surface thereof that conforms to human engineering principles.