Ratchet wrench with lighting means

A ratchet wrench comprising a hollow ratchet unit having a coupling shaft at one end and a steel ball revolvably supported in a side hole on said coupling shaft, and a lighting unit mounted in said hollow ratchet unit and controlled to emit light, wherein said lighting unit comprises:

• a hollow guide shaft mounted in said hollow ratchet unit, said hollow guide shaft comprising a recessed portion at the periphery near one end thereof, which receives said stell ball, a head at an opposite end, a receving chamber defined within said head, said receiving chamber having a narrow bottom end longitudinally extended through said hollow guide shaft, and an inner thread inside said receiving chamber;
• a metal spring mounted around said hollow guide shaft inside said hollow ratchet unit, said metal spring imparting an upward pressure to the head of said hollow guide shaft;
• a lamp assembly mounted in said hollow guide shaft, said lamp assembly comprising a lamp bulb at one end, a metal contact plate at an opposite end, said metal contact plate comprising a projecting strip, a projecting strip integral with said metal contact plate, and lead wires connected between said lamp bulb and said metal contact plate;
• a battery set mounted in the receiving chamber of said hollow guide shaft and supported on the projecting strip of said metal contact plate of said lamp assembly;
• an electrically conductive plate mounted inside the receiving chamber of said hollow guide shaft, said electrically conductive plate having a projecting strip stopped against one end of said battery set opposite to said metal contact plate of said lamp assembly;
• and
• a knob having an outer thread threaded into the inner thread of said hollow guide shaft, said knob being rotated to turn on/off said lamp assembly.