Patent ID: 7992483

Claim:
A firing frequency controller, comprising: a cylinder body including a first end portion and a second end portion, said first end portion containing a first orifice and said second end portion containing a third orifice, said cylinder body further including a second orifice disposed between said first orifice and said third orifice, the amount of the gas flux through the first orifice being not equal to that through the third orifice; a piston assembly which is disposed inside said cylinder body including a piston and a pole, said piston being repeatedly moved between the first end portion and the second end portion, said pole being connected to the piston and extended to exterior of the first end portion of the cylinder body, the stroke from the first orifice to the second orifice being defined as first route, the stroke from the second orifice to the third orifice being defined as second route, the stroke from the third orifice to the second orifice being defined as third route, the stroke from the second orifice to the first orifice being defined as fourth route; and a unidirectional seal being disposed at outside of said piston and adjacent to the inner wall of the cylinder body; wherein, when the piston is moved in the third route and the fourth route said unidirectional seal is contacted with the inner wall of the cylinder body and is kept airtight, when the piston is moved in the first route and the second route said unidirectional seal is not contacted with the inner wall of the cylinder body and is kept non-airtight.