Patent ID: 7810368

Claim:
A multi-mode hammering apparatus for shaping a workpiece such as sheet metal, said multi-mode hammering apparatus comprising: a die secured to a support structure, said die and support structure being adapted to receive the workpiece; a ram cyclically movable along a path of travel toward and away from said die between fully extended and fully retracted ram positions that define a stroke length of said ram; a ram drive assembly including a motor, lever drive assembly and lever, said motor cyclically driving said lever drive assembly at a selectively variable rate of speed between fully extended and fully retracted drive positions, said lever being pivotable about a pivot axis, joined to said lever drive assembly on a first side of said pivot axis and joined to said ram on a second side of said pivot axis, said lever further including a rigid drive and a flexible drive, said rigid drive having at least one load bearing rigid member rigidly joining said lever drive assembly to said ram, and said flexible drive having at least one load bearing flexible member flexibly joining said lever drive assembly to said ram, said ram drive assembly cyclically moving said ram between said fully extended and a fully retracted ram positions; and, wherein said ram drive assembly operates in a rigid reciprocating mode when said rigid drive is engaged and a flexible power hammer mode when said flexible drive is engaged, said stroke length of said ram being rigidly held by said ram drive assembly when in said rigid reciprocating mode, and said stroke length of said ram being flexibly held by said ram drive assembly and increasing with said speed of said motor when in said power hammer mode.