Patent ID: 7040414
Filing Date: 2006-05-09
Classification: B25B,F01C

Abstract:
1. A pneumatic tool comprising: a housing formed with a component chamber and an intake passageway, said component chamber having a rear end; a driving mechanism mounted in said component chamber and including a rear cap having a peripheral wall coupled to said housing at said rear end of said component chamber, said peripheral wall defining a cap chamber that is in spatial communication with said component chamber, said rear cap being formed with a connecting passageway that intercommunicates said cap chamber and said intake passageway; a direction controller mounted in said cap chamber and rotatable about said rotary axis, said direction controller including a base wall transverse to said rotary axis, and first and second abutment posts that project from said base wall and that are disposed to abut against said rear side of said rear bearing member, said direction controller having a second forward hole formed through said base wall and said first abutment post, and a second reverse hole formed through said base wall and said second abutment post; a speed controller mounted in said cap chamber and rotatable about said rotary axis, said speed controller including a ring wall formed with a forward speed regulator and a reverse speed regulator, and an operating part that extends from said ring wall in a direction away from said component chamber and that is accessible externally of said rear cap and said housing; and an operating member coupled to said direction controller and accessible externally of said rear cap and said housing; said operating member being operable to drive rotation of said direction controller about said rotary axis for aligning said first and second forward holes such that air for driving forward rotation of said output shaft is able to flow into said cylinder chamber via a first flow path that includes said intake passageway, said connecting passageway, said forward speed regulator, and said first and second forward holes; said operating member being further operable to drive rotation of said direction controller about said rotary axis for aligning said first and second reverse holes such that air for driving reverse rotation of said output shaft is able to flow into said cylinder chamber via a second flow path that includes said intake passageway, said connecting passageway, said reverse speed regulator, and said first and second reverse holes; said operating part of said speed controller being operable to vary extent of overlap between one of said forward and reverse speed regulators and a corresponding one of said second forward and reverse holes for regulating amount of air flow through one of said first and second flow paths, thereby varying torque and speed of said output shaft accordingly.