Patent ID: 8499852

Claim:
A switch used in a pneumatic tool comprising an air intake passage and a gas control member set in said air intake passage, the switch comprising: a valve seat defining an air hole, said valve seat being set in said air intake passage and movable relative to said air intake passage into contact with or away from said gas control member; and a valve rod comprising a positioning portion, said valve rod being inserted through said air hole of said valve seat and biasable relative to said valve seat to stop said positioning portion against said air hole or to move said positioning portion away from said air hole; wherein when said positioning portion of said valve rod is stopped against said valve seat and said valve seat is stopped against said gas control member, said air intake passage is blocked; when said valve rod is biased relative to said valve seat, said positioning portion is moved away from said air hole of said valve seat for allowing a compressed gas to pass through said air hole, and when said valve rod is biased further to carry said valve seat away from said gas control member, said compressed gas is allowed to pass between said valve seat and said gas control member, wherein said valve seat comprises an annular seat base, said air hole is at a center of said annular seat base to form an inside wall of said annular seat base which extends around said air hole, said annular seat base comprises at least one groove located on the inside wall.