Reciprocating press

A reciprocating press for acting on a workpiece, comprising:

• an eccentric shaft rotatably disposed in a rotatable eccentric sleeve;
• a crank-slider mechanism coupled to the eccentric shaft;
• a first electric motor operably coupled to the eccentric shaft;
• and
• a second electric motor operably coupled to the rotatable eccentric sleeve;
• wherein the first and second electric motors are independently controllable to control rotations of the eccentric shaft and the rotatable eccentric sleeve to dynamically vary a reciprocating stroke length of the crank-slider mechanism;
• wherein an upper portion of the eccentric shaft is coupled to the first electric motor via an offset coupler and a harmonic gearset;
• wherein a middle portion of the eccentric shaft is arranged to rotate within an inner portion of the rotatable eccentric sleeve;
• and
• wherein a crankpin is disposed on a lower portion of the eccentric shaft.

A reciprocating press, comprising:

• an eccentric shaft, a rotatable eccentric sleeve, a crank-slider mechanism, a first electric motor, a second electric motor, a housing portion, a base portion, and a mount portion;
• the eccentric shaft being rotatably disposed within the rotatable eccentric sleeve, and the rotatable eccentric sleeve being rotatably disposed in the housing portion;
• the eccentric shaft including a crankpin;
• the eccentric shaft rotatably coupled to the first electric motor;
• the rotatable eccentric sleeve rotatably coupled to the second electric motor;
• the crank-slider mechanism including a piston and a connecting rod;
• the piston of the crank-slider mechanism being disposed in and translatable in the mount portion;
• the crankpin being disposed in the base portion;
• and
• the connecting rod of the crank-slider mechanism being coupled to the crankpin;
• wherein the piston is arranged to act upon a workpiece that is disposed adjacent to the mount portion;
• wherein the piston of the crank-slider mechanism is arranged to reciprocate in the mount portion by rotations of the eccentric shaft and the rotatable eccentric sleeve;
• and
• wherein the first and second electric motors are independently controllable to control rotations of the eccentric shaft and the rotatable eccentric sleeve to dynamically vary a stroke length of the piston;
• wherein an upper portion of the eccentric shaft is coupled to the first electric motor via an offset coupler and a harmonic gearset;
• wherein a middle portion of the eccentric shaft is arranged to rotate within an inner portion of the rotatable eccentric sleeve;
• and
• wherein the crankpin is disposed on a lower portion of the eccentric shaft.

A method for controlling a reciprocating press, the reciprocating press including an eccentric shaft rotatably disposed in a rotatable eccentric sleeve, a crank-slider mechanism coupled to the eccentric shaft, a first electric motor operably coupled to the eccentric shaft, and a second electric motor operably coupled to the rotatable eccentric sleeve, the method comprising:

• controlling an angular position of the first electric motor and controlling an angular position of the second electric motor;
• and
• dynamically controlling a stroke of a piston of the crank-slider mechanism based upon the angular positions of the first and second electric motors;
• wherein the first and second electric motors are independently controllable to control the angular positions of the eccentric shaft and the rotatable eccentric sleeve to control the stroke of the piston;
• wherein an upper portion of the eccentric shaft is coupled to the first electric motor via an offset coupler and a harmonic gearset;
• wherein a middle portion of the eccentric shaft is arranged to rotate within an inner portion of the rotatable eccentric sleeve;
• and
• wherein a crankpin is disposed on a lower portion of the eccentric shaft.