Patent ID: 6032509
Filing Date: 2000-03-07
Classification: B21D

Abstract:
A press brake for bending a workpiece between a lower mold and an upper mold, comprising:a bed extending in a first direction for supporting said lower mold on an upper surface thereof;a ram extending in said first direction for supporting said upper mold in opposition to said lower mold;driving means for displacing one of said ram and said bed relative another one of said ram and said bed to in a pressing direction to press the workpiece between said upper mold and said lower mold;distance adjusting means for adjusting a distance between said upper mold and said lower mold including a wedging unit disposed at one of a first position between said ram and said upper mold and a second position between said bed and said lower mold;said wedging unit including first and second movable wedge members respectively having first and second movable engagement surfaces extending in said first direction and a stationary wedge member disposed between said first and second movable wedge members and having opposing first and second stationary engagement surfaces extending in said first direction and respectively in engagement with said first and second movable engagement surfaces to define respectively first engaged surfaces and second engaged surfaces;said first engaged surfaces being comprised of a series of pairs of complementing inclined engaged surfaces serially disposed in said first direction and having differing angles of inclination relative to said first direction such that relative movement of said first engaged surfaces in said first direction effects relative displacement of said first movable wedge member with respect to said stationary wedge member in said pressing direction in displacement amounts that vary along said first direction to define a first deflection configuration;said second engaged surfaces being comprised of a series of pairs of complementing inclined engaged surfaces serially disposed in said first direction and having differing angles of inclination relative to said first direction such that relative movement of said second engaged surfaces in said first direction effects relative displacement of said second movable wedge member with respect to said stationary wedge member in said pressing direction in displacement amounts that vary along said first direction to define a second deflection configuration; andsaid distance adjusting means further comprising first and second reciprocating units coupled to said first and second movable wedge members respectively to move said first and second movable wedge members along said first direction.