Manually operated impact tool

A manually operated rotatable impact tool comprising:

• a driven member having means for retaining and driving a fastener about an axis, the driven member further having at least one anvil surface offset from the axis;
• a driving member rotatably connected to the driven member for driving the driven member about the axis to loosen or tighten the fastener, the driving member having at least one anvil in cooperation with the at least one anvil surface;
• biasing means for biasing the at least one anvil surface and at least one anvil together;
• at least one cam for engaging a surface of the driving member and for moving the at least one anvil apart from the corresponding at least one anvil surface upon rotation of the cam and for releasing the driving member such that the spring pulls the at least one anvil to impact the corresponding at least one anvil surface to create a torque around the axis.

A manually operated rotatable impact tool comprising:

• a driven member having means for retaining and driving a fastener about an axis, the driven member further having at least one anvil offset from the axis, the anvil being rotatably disposed in the driven member into and out from a path;
• a driving member rotatably connected to the driven member for driving the driven member about the axis to loosen or tighten the fastener;
• an impact mass movable along the path in communication with the at least one anvil;
• a flexible member connecting the driving member and impact mass for storing energy upon rotation of the driving member;
• and
• energy releasing means for releasing the stored energy and allowing it to be at least partially transferred to the impact mass such that the impact mass accelerates and strikes the at least one anvil upon the release of the stored energy while the at least one anvil is rotated into the path.