A sliding frictional force generation mechanism includes a metal hole member having a hole, a metal shaft member fitted in the hole of the hole member in an axially slidable manner, and a lubrication mechanism configured to supply lubricating oil serving as a cooling medium between the holed ember and the shaft member. The shaft member is fitted in the hole in an interference fit state.

A die cushion device of a press machine includes a hydraulic cylinder that supports a cushion pad and generates die cushion force when a slide of the press machine descends, an orifice and a hydraulic pump/motor that are connected to each other in in parallel between a lower chamber of the hydraulic cylinder and a tank, a servo motor connected to a rotating shaft of the hydraulic pump/motor, and a control unit that controls torque of the servo motor to control the die cushion force, wherein a rotation direction of the servo motor switches from a first rotation direction in which the hydraulic pump/motor serves as a hydraulic motor to a second rotation direction in which the hydraulic pump/motor serves as a hydraulic pump, during generation of the die cushion force.

A die cushion device of a press machine includes a hydraulic cylinder that supports a cushion pad and generates die cushion force when a slide of the press machine descends, an orifice and a hydraulic pump/motor that are connected to each other in in parallel between a lower chamber of the hydraulic cylinder and a tank, a servo motor connected to a rotating shaft of the hydraulic pump/motor, and a control unit that controls torque of the servo motor to control the die cushion force, wherein a rotation direction of the servo motor switches from a first rotation direction in which the hydraulic pump/motor serves as a hydraulic motor to a second rotation direction in which the hydraulic pump/motor serves as a hydraulic pump, during generation of the die cushion force.

A single action draw press and a draw die set for the single action draw are disclosed. The single action draw press and die include a bolster and a stationary punch. A cushion is assembled to the bolster to support a binder ring that is adapted to be engaged by a die attached to a press ram. The die is reciprocated by the press ram relative to the bolster while a mechanical lock engages the die and the binder ring. The die contacts the binder ring and a mechanical lock secures the die and binder ring together while the die draws a panel over the stationary punch.

A single action draw press and a draw die set for the single action draw are disclosed. The single action draw press and die include a bolster and a stationary punch. A cushion is assembled to the bolster to support a binder ring that is adapted to be engaged by a die attached to a press ram. The die is reciprocated by the press ram relative to the bolster while a mechanical lock engages the die and the binder ring. The die contacts the binder ring and a mechanical lock secures the die and binder ring together while the die draws a panel over the stationary punch.

A controllable force cushion device that can be programmed to provide a variable and/or pulsating force that can be used in any application where force control is desirable. The frequency of the pulsation can be adjusted to suit different applications and/or circumstances (e.g., forming of sheet metals in die applications, etc.). The cushion can comprise one or more manifolds containing hydraulic cylinders that can be compressed during operation pushing fluid through a proportional relief valve that can be controlled by a motion control device, thereby creating a desired force. Material (e.g., sheet metal, etc.) flow can be controlled by using a gap control method. In use, the variable pulsating, gap control, auto-learning press cushion device of the present invention can optionally be mounted to the underside of a press bolster and can be used in conjunction with a stamping press.

A controllable force cushion device that can be programmed to provide a variable and/or pulsating force that can be used in any application where force control is desirable. The frequency of the pulsation can be adjusted to suit different applications and/or circumstances (e.g., forming of sheet metals in die applications, etc.). The cushion can comprise one or more manifolds containing hydraulic cylinders that can be compressed during operation pushing fluid through a proportional relief valve that can be controlled by a motion control device, thereby creating a desired force. Material (e.g., sheet metal, etc.) flow can be controlled by using a gap control method. In use, the variable pulsating, gap control, auto-learning press cushion device of the present invention can optionally be mounted to the underside of a press bolster and can be used in conjunction with a stamping press.

An industrial gas spring with a pressure chamber in a casing with an end wall, a piston rod received at least in part in the casing for reciprocation between extended and retracted positions and a pressure relief assembly carried by the end wall. The pressure relief assembly may have a membrane communicating with the pressure chamber and a plunger configured to breach the membrane when engaged and moved by the piston rod when it overtravels its design intended retracted position.

A method for producing a pot-shaped component from a flat blank. The method comprises the following steps: a) shaping the flat blank in at least one deep-drawing step to form a pot-shaped raw component having a substantially flat bottom area and a circumferential frame, and b) shaping the pot-shaped raw component in a tool having a conically tapered die that applies shear to the circumferential surface of the frame in the axial direction against the conically tapered die. In step b), the bottom area is clamped between an ejector and a hold-down mechanism and the conically tapered die surrounds the bottom area of the raw component radially on the outside and extends in a diameter-reducing manner in a tool stroke.

A method for producing a pot-shaped component from a flat blank. The method comprises the following steps: a) shaping the flat blank in at least one deep-drawing step to form a pot-shaped raw component having a substantially flat bottom area and a circumferential frame, and b) shaping the pot-shaped raw component in a tool having a conically tapered die that applies shear to the circumferential surface of the frame in the axial direction against the conically tapered die. In step b), the bottom area is clamped between an ejector and a hold-down mechanism and the conically tapered die surrounds the bottom area of the raw component radially on the outside and extends in a diameter-reducing manner in a tool stroke.