Adjustable stroke mechanism

A mechanical press, comprising:

• a rotatable crankshaft;
• at least one eccentric crankshaft member rotatably driven by said rotatable crankshaft;
• at least one eccentric bushing each disposed about a respective said eccentric member to define a respective interface therebetween, each said eccentric bushing and said associated eccentric member being releasably connectable with one another, each said eccentric bushing being normally operatively arranged in a press-fit connection with said associated eccentric member;
• at least one press connection member each disposed in operative driving connection with a respective said eccentric bushing;
• a bushing fit control means, being operative in a bushing expansion mode during a press stroke adjustment operation to reversibly remove each said eccentric bushing from the normal press-fit connection with said associated eccentric member by expanding said eccentric bushing at least in part towards its associated press connection member, and being further operative in a bushing contraction mode to restore each said eccentric bushing subjected to expansion to the normal press-fit connection with said associated eccentric member;
• an angle control means, operative during at least one of the respective bushing expansion mode and the respective bushing contraction mode associated with at least one of said eccentric bushings, for controlling at least one of the slide position crank angle of said crankshaft and the respective bushing angle for at least one of said eccentric bushings, the control function performed by said angle control means being directed towards minimization of relative bushing angle slip between respective pairs of said eccentric bushings and said eccentric members;
• and
• means for driving said crankshaft in rotation by applying a driving rotation to said crankshaft at a plurality of axial locations along said crankshaft, during the press stroke adjustment operation.

A mechanical press having a slide, said press comprising:

• a rotatable crankshaft;
• at least one eccentric crankshaft member rotatably driven by said rotatable crankshaft;
• at least one eccentric bushing each disposed about a respective said eccentric member to define a respective interface therebetween, each said eccentric bushing and said associated eccentric member being releasably connectable with one another, each said eccentric bushing being normally operatively arranged in a press-fit connection with said associated eccentric member;
• at least one press connection member each disposed in operative driving connection with a respective said eccentric bushing and said slide;
• a bushing fit adjustment means for reversibly removing each said eccentric bushing from the press-fit connection with said associated eccentric member during a press stroke adjustment operation;
• means for driving said crankshaft in rotation by applying a driving rotation to said crankshaft at a plurality of axial locations along said crankshaft, during the press stroke adjustment operation;
• a controller to activate said driving means;
• and
• a device for measuring slide parallelism and transferring measurement data to said controller.