Piezoelectric lighter with impact mechanism

Claim 1

A piezoelectric igniter of the type normally used in a lighter comprising a magnetically non-conductive housing; a piezoelectric transducer and an impact mechanism disposed in said housing anD including a hammer movable between a normal rest position and an impact position away from said rest position and whereat said hammer has an impact with said transducer; an electric circuit including electrical leads and electrodes connected to the piezoelectric transducer for ignition purposes; spring means being operable to exert a force against said hammer in a direction toward said transducer when the potential energy of the spring means is increased; resilient retraction means for said hammer of smaller force than said spring; an actuating member operable to increase the potential energy of said spring means; and a magnetic circuit comprising a fixed part, a movable part, one of said parts including a magnet having pole faces and both said parts being magneticallyconductive, said parts being sufficiently closely adjacent each other in the rest position of the hammer for closing the magnetic circuit substantially free from any air gap, said movable part being connected to the hammer and being movable therewith and being operable due to the magnetic force exerted between said parts to hold said hammer in said rest position against the force of said spring means throughout that portion of the increase in potential energy of said spring means which is at least inferior to said magnetic force; said hammer including a pot-shaped magneticallyconductive member disposed in said hammer and having an open side, said movable part being a magnet disposed in said member, said fixed part comprising a magnetically-conductive yoke, the open side of said magnetically-conductive member being disposed next to said yoke in the rest position of said hammer.