A press system includes a press portion and a controller configured to control the press portion. The controller includes a load pattern generator, an evaluation input unit, and an optimum load pattern setting unit configured to set an optimum load pattern based on a plurality of evaluations of the quality input by the evaluation input unit. The optimum load pattern setting unit includes a response surface generator configured to create from evaluation value data based on the plurality of load patterns and the plurality of evaluations of the quality, by using as an objective function, the evaluation value data with the load pattern being defined as a design variable, a response surface of the objective function, and an optimization calculator configured to find an optimum solution of the objective function of the response surface by optimization.

A press system includes a press portion and a controller configured to control the press portion. The controller includes a load pattern generator, an evaluation input unit, and an optimum load pattern setting unit configured to set an optimum load pattern based on a plurality of evaluations of the quality input by the evaluation input unit. The optimum load pattern setting unit includes a response surface generator configured to create from evaluation value data based on the plurality of load patterns and the plurality of evaluations of the quality, by using as an objective function, the evaluation value data with the load pattern being defined as a design variable, a response surface of the objective function, and an optimization calculator configured to find an optimum solution of the objective function of the response surface by optimization.

A method of forming a finished stamped product includes positioning a blank on a blank holder between an upper die and a lower die, inserting a movable wedge block between the blank holder and the upper die to establish a first binder gap, and while the movable wedge block is inserted, performing a first strike of the blank by lowering the upper die a first distance to contact and partially form the blank, the movable wedge block limiting downward movement of the upper die relative to the lower die. After the first strike, withdrawing the movable wedge block to establish a second binder gap between the blank holder and the upper die, and while the movable wedge block is withdrawn, performing a second strike of the blank by lowering the upper die a second distance to finally form the blank into the finished product.

A die is configured for use with a punch capable of piercing and cutting a workpiece. The die includes a base wall having a perimeter, an outer surface and an inner surface, a depending wall extending from the perimeter, a passageway extending through the base wall, and a central axis extending through the passageway. The outer surface of the base wall is perpendicular to the central axis. The inner surface of the base wall has a first portion which is angled relative to the central axis at a first angle which is greater than 90 degrees, and a second portion which is angled relative to the central axis at a second angle which is greater than 90 degrees. The first and second angles are different. The first portion extends from the depending wall to the second portion. The second portion extends from the first portion to the passageway. The second portion engages the punch when the punch is fully inserted into the die.

To reduce warping of vertical wall portions without causing buckling during pressing. Press-forming into a hat cross-sectional shape having one linear vertical wall portion and the other curved vertical wall portion and not having a flange portion is performed. A punch and a pad sandwiching a top sheet portion therebetween, bending blades, and stoppers are provided. The punch is supported by a first cushion component. The bending blades each have an upper die component and a lower die component disposed facing each other in the press direction with an interval (D) equal to a set compression amount in the range of 2% or more and 6% or less of the heights of the vertical wall portions and a second cushion component interposed between the upper die component and the lower die component, maintaining the interval (D), and contractible in the press direction. The cushion pressure of the second cushion component is lower than the cushion pressure of the first cushion component and has such cushion pressure that the second cushion component does not contract during the bend-forming of the vertical wall portions. The clearance between the side surface of the punch and the bending blades is 90% or more of the sheet thickness of a material to be processed and less than the sheet thickness.

A servo motor controller comprises: a position command generation unit; a position detection unit; a position control unit that generates a velocity command for position control based on a position command and a position FB; a force command generation unit that generates a force command for instructing force to be applied to a subject by a driving target; a force detection unit; a force control unit that generates a velocity command for force control based on the force command and a force FB; a selection unit that selects one of the position control and the force control; and a storage unit that stores a force threshold. The selection unit selects one of the velocity commands for the position control and the force control of a smaller value. If the force FB is smaller than the force threshold, the selection unit selects the velocity command for the position control.

A servo motor controller comprises: a position command generation unit; a position detection unit; a position control unit that generates a velocity command for position control based on a position command and a position FB; a force command generation unit that generates a force command for instructing force to be applied to a subject by a driving target; a force detection unit; a force control unit that generates a velocity command for force control based on the force command and a force FB; a selection unit that selects one of the position control and the force control; and a storage unit that stores a force threshold. The selection unit selects one of the velocity commands for the position control and the force control of a smaller value. If the force FB is smaller than the force threshold, the selection unit selects the velocity command for the position control.

A hydraulic drawing cushion (17) for a drawing press (10) includes at least one hydraulic cylinder (21) comprising a piston rod (27) that causes a total force (G) to act on the metal sheet holding ring (20). The hydraulic cylinder (21) comprises a hydraulic work circuit (37) to generate a hydraulic work force (A) in a work direction (Z) to act on a ring part (28) to which a force can be applied on both sides. Independently, a spring force (F) acts on the piston (26). The spring force (F) is neither controlled nor adjusted, but is preset. Preferably, the spring force (F) is exclusively a function of the position or location of the piston (26) relative to the cylinder housing (25). The total force (G) acting on the piston (26) results from the addition of the vectors of the work force (A) and the spring force (F).

A hydraulic drawing cushion (17) for a drawing press (10) includes at least one hydraulic cylinder (21) comprising a piston rod (27) that causes a total force (G) to act on the metal sheet holding ring (20). The hydraulic cylinder (21) comprises a hydraulic work circuit (37) to generate a hydraulic work force (A) in a work direction (Z) to act on a ring part (28) to which a force can be applied on both sides. Independently, a spring force (F) acts on the piston (26). The spring force (F) is neither controlled nor adjusted, but is preset. Preferably, the spring force (F) is exclusively a function of the position or location of the piston (26) relative to the cylinder housing (25). The total force (G) acting on the piston (26) results from the addition of the vectors of the work force (A) and the spring force (F).

A double-blank detecting apparatus for a press machine that is provided with a die cushion apparatus and is configured to form blanks one by one automatically and repeatedly. The double-blank detecting apparatus includes: a position signal acquiring unit configured to acquire a slide position signal indicating a position of a slide of the press machine; a load signal acquiring unit configured to acquire a die cushion load signal indicating a die cushion load generated on a cushion pad of the die cushion apparatus; and a double-blank detector configured to detect a state in which a plurality of blanks are stacked as a double blank based on the slide position signal acquired by the position signal acquiring unit and the die cushion load signal acquired by the load signal acquiring unit.