Patent ID: 7797841

Claim:
A reciprocating drive apparatus comprising; a housing; a drive shaft rotatably mounted in said housing; an elongated plunger mounted in said housing for reciprocating motion; said plunger having a rear end portion configured to engage a wobble plate interface structure and a cylindrically shaped front end portion with a first center axis for attaching a tool; a first bushing positioned in said housing for retaining said front end portion in a manner whereby said plunger is not restrained from rotating about a first axis of rotation; a second bushing positioned in said housing for receiving said rear end portion of said elongated plunger, said rear end portion having a circular outer surface and a second center axis and being configured to contact said second bushing during reciprocation of said plunger in said bushing; a wobble plate assembly operatively connected to said drive shaft and having an elongated arm with a wobble plate interface structure for engaging said rear end portion of said plunger and reciprocating said plunger in said first and second bushings; wherein said first and second center axes are offset relative to one another.