Portable seam locking device

Claim 1

A portable seam locking device for forming a fold over seam joint between two metal flanges comprising, a. a portable housing having a recessed anvil surface formed on and extending longitudinally of an outer surface thereof, said anvil surface having first and second faces disposed perpendicular to one another in an L-shaped configuration, b. A hammer pivotably mounted in said housing for oscillating movement, between a first and second position, about a pivot axis which is disposed rearwardly from said second face at a level above said first face in a plane parallel to the plane of said anvil surface, c. said hammer having a head portion at one end thereof projecting outwardly from said housing to overlie said anvil surface, said head portion having a ridge portion which, when said hammer is in said first position, projects outwardly from the head portion in a direction towards said first face and is spaced outwardly from said second face of said anvil surface, d. said hammer being pivotable in response to movement to said second position to move said ridge in an arc which curves towards both said first and second faces whereby said ridge is disposed more closely adjacent both said first and second faces when in said second positions to draw a seam joint inwardly of said housing during folding thereof by engagement with said ridge, e. drive means within said housing engaging said hammer and causing said hammer to oscillate about said pivot point to move said head portion to and fro between said first and second positions, said drive means including input drive shaft means connectible to a source of rotary power.