Reversible screwdriver

A reversible screwdriver comprising:

• a) a handle including a front end;
• b) a driving block secured to the front end of the handle, the driving block inncluding a recessed round hole, and a side slot intersecting with the recessed round hole,
• c) a hollow substantially cylindrical front cap including a front end wall, a side wall, a center hole formed in the front end wall, a first recess and a second recess provided at opposite sides of an internal portion of the sidewall, and the front cap enclosing and rotatably fastened to the driving block;
• d) a transmission shaft including a ratchet wheel disposed within the recess round hole of the driving block and a square tip extending outwardly through the center hole of the front cap;
• e) a first stop block and a second stop block disposed within the side slot of the driving block, for selective engagement with the ratchet wheel and the first and second recesses of the front cap upon rotation of the cap in the clockwise and counter-clockwise directions;
• and
• f) wherein the front cap may be rotated to a first position disposing both the first and second stop blocks into engagement with the ratchet wheel to permit the transmission shaft to be turned by the handle in either a clockwise or a counter-clockwise direction, a second position wherein the first stop block is disposed within the first recess and the second stop block is disposed in engagement with the ratchet wheel to permit the handle to turn the transmission shaft in only the clockwise direction, a third position wherein the second stop block is disposed within the second recess and the first stop block disposed in engagement with the ratchet wheel to permit the handle to turn the transmission shaft only the counter-clockwise position.