An apparatus for the controlled return of the stems in cylinders of the types that can be applied to a press for stamping sheet metal, comprising: at least one fluid-operated cylinder), at least one hydraulic accumulator which is fluidically connected to the at least one cylinder by means of a hydraulic circuit which comprises: a duct for the discharge of the working fluid from the at least one cylinder and a duct/branch for the intake of the working fluid in the hydraulic accumulator, a duct for loading the working fluid in the at least one cylinder and at duct/branch for the output of the working fluid from the hydraulic accumulator.

A method for material forming and/or cutting by means of a tool and a drive unit. The method includes moving the drive unit to provide kinetic energy to the tool, for the tool to strike a work material, so as to form and/or cut the work material when the tool is operatively disassociated from the drive unit before the tool strikes the work material.

A hydraulic press includes a workbench having four corners provided with uprights. The uprights are arranged in two rows front and rear, and the tops of the uprights in each row are connected by an upper beam extending in a left-right direction. Tie rods are inserted in the front and rear of each upright. The tie rods each have an upper end protruding from the top of the upper beam and fixed to the upper beam by an upper nut and a lower end protruding from the bottom of the workbench and fixed to the workbench by a lower nut. A central cylinder is provided at the center of the upper beam. Side cylinders are symmetrically arranged on the left and right of the central cylinder. The lower ends of plungers of the central cylinder and the side cylinders are fixedly connected to a top of a slider.

An electro-hydrostatic drive for realizing a rapid movement during a rapid movement phase, a force-building movement during a force-building movement phase. The apparatus comprises a hydro-machine with variable volume and/or rotational speed, driven by an electric motor, for providing a volume-stream of a hydraulic fluid, a first cylinder with a piston chamber, an rod chamber, and a plunger rod, a reservoir, a pressure source, a relief valve, a check valve, a fluid connection between the piston chamber and the hydro-machine, a fluid connection between the rod chamber and the hydro-machine, a fluid connection between the piston chamber and the reservoir, a fluid connection between the rod-chamber-side port of the hydro-machine and the reservoir, a fluid connection, through the relief valve, between the reservoir and the pressure source. The relief valve is for pressure safety of the reservoir, and the check valve has a fluid connection from the pressure source to the rod-chamber-side port of the hydro-machine, during the rapid movement phase, a first part of the hydraulic fluid is piped through the fluid connection between the piston chamber and the hydro-machine and the fluid connection between the rod chamber and the hydro-machine, and a second part of the hydraulic fluid communicates through the fluid connection between the piston chamber and the reservoir, during the force-building movement phase, a first part of the hydraulic fluid is piped through the fluid connection between the piston chamber and the hydro-machine and the fluid connection between the rod chamber and the hydro-machine, and a second part of the hydraulic fluid is piped through the fluid connection between the rod-chamber-side port of the hydro-machine and the reservoir.

A semiconductor device is located between a first die-set part and a second die-set part of a press, and the first and second die-set parts are moved relative to each other for punching and shaping the semiconductor device therebetween. At least one parameter is monitored with at least one sensor attached to the first die-set part and/or the second die-set part at different positions of the first die-set part when it is moving relative to the second die-set part. Variations of the at least one parameter at different relative positions of the first and second die-set parts are compared, and a failure is determined to have occurred when the present variation of the parameter is different from its expected variation during normal operation of the press when there is no failure.

A press device includes a slide configured to hold a first die, a holding portion configured to hold a second die, a reciprocating mechanism that causes the slide to reciprocate in a stroke direction in which the first die and the second die move closer to or away from each other, and a pressurizing mechanism that holds the second die while pressurizing the second die toward the first die with a stroke shorter than that of the reciprocating mechanism in a state where the first die and the second die are moved close to each other by the reciprocating mechanism.

A press device includes a slide configured to hold a first die, a holding portion configured to hold a second die, a reciprocating mechanism that causes the slide to reciprocate in a stroke direction in which the first die and the second die move closer to or away from each other, and a pressurizing mechanism that holds the second die while pressurizing the second die toward the first die with a stroke shorter than that of the reciprocating mechanism in a state where the first die and the second die are moved close to each other by the reciprocating mechanism.

A method for pressing a workpiece with a predetermined pressing force uses a forming tool coupled with an electric motor via a spindle drive that converts the rotational movement of the electric motor drive shaft to a translational movement of the forming tool. The method includes: accelerating the electric motor in a first rotational direction to a predetermined maximal speed of rotation; operating the electric motor at the maximal speed until the drive shaft has completed a predetermined number of revolutions; reducing the speed of rotation of the electric motor to a predetermined reduced speed of rotation; operating the electric motor at the reduced speed until a pressing force increase exceeding a predetermined threshold value is detected by a measuring unit that follows the electric motor; forming the workpiece with constant detection of the pressing force by the measuring unit until the predetermined pressing force has been reached.

Retrofit systems for converting a manual press to an automated press. The retrofit systems include a first shaft, a second shaft, a first spacer, and a second spacer. The first shaft is mounted to a first vertical member and is coupled to a first cross member and to a second cross member. The second shaft is mounted to a second vertical member and is coupled to the first cross member and to the second cross member. The first spacer is supported by the first shaft and is disposed between the first vertical member and the first cross member. The second spacer is supported by the second shaft and is disposed between the second vertical member and the first cross member. The first spacer and the second spacer are selected to increase the space between the first cross member and the second cross member to accommodate an automatically actuated press.

Retrofit systems for converting a manual press to an automated press. The retrofit systems include a first shaft, a second shaft, a first spacer, and a second spacer. The first shaft is mounted to a first vertical member and is coupled to a first cross member and to a second cross member. The second shaft is mounted to a second vertical member and is coupled to the first cross member and to the second cross member. The first spacer is supported by the first shaft and is disposed between the first vertical member and the first cross member. The second spacer is supported by the second shaft and is disposed between the second vertical member and the first cross member. The first spacer and the second spacer are selected to increase the space between the first cross member and the second cross member to accommodate an automatically actuated press.