A press machine includes a press frame, a crankshaft having a first eccentric portion, at least one crankshaft motor connected to the crankshaft, a ram, an upper tool section supported by the ram and a lower tool section fixedly attached to the press frame, a linkage type ram drive mechanism connected to the crankshaft and including at least one pivot support pin, and a ram adjustment mechanism including a pivot support member supporting the at least one pivot support pin. Wherein the at least one secondary ram drive link is pivotally connected at a first end to the at least one pivot support pin and at a second end to a first end of the at least one main ram drive link. The at least one main ram drive link is pivotally connected at a second end to the ram. The at least one ram drive connecting link is rotatably supported by the at least one first eccentric portion of the crankshaft at a first end and pivotally connected at a second end to the at least one main ram drive link at a point between the first and second ends of the at least one main ram drive link.

The drawing press (10) according to the invention has for driving its ram (15) a directionally reversing gear mechanism (22, 54), for example a coupling gear mechanism, and at least one servomotor (23). The servomotor (23) passes through the reversal point (Ut) of the ram movement, which is predetermined by the kinematics of the coupling gear mechanism, for example the extended position of an eccentric drive. During the closing of the die (18), that is to say during a press stroke, the servomotor (23) is activated in such a way that it first passes through this reversal point (Ut), then stops, reverses and then passes through it once again, in order to open the die (18) again. Consequently, the braking to a standstill and re-acceleration of the servomotor for the upper ram (15) takes place while the actual drawing operation is still or already being performed, i.e. during the forming of the metal blank, which significantly reduces the cycle time.

A method for operating a punching press with a press plunger driven by a crank drive, which operates in a machining zone of the punching press against a stationary clamping plate, and with a servo feed apparatus for intermittently feeding a band of material to be processed to the machining zone. In punching mode, the press plunger is moved back and forth by the crank drive between a first movement dead point (0), in which the press plunger is at maximum distance from the clamping plate, and a second movement dead point (180), in which the press plunger is at minimum distance from the clamping plate. In the process, the material band is pushed by the servo feed apparatus around the first movement dead point (0) in a first rotation angle window (3) of the crank drive by a certain length into the machining zone and processed in a second rotation angle window during the feed pauses. The feed movement of the servo feed drive takes place according to an electronically defined feed movement profile (5), which is followed in the first rotation angle window (3) in an electronically synchronized manner to the rotation of the crank drive (4). When a press stop (6) is triggered in the first rotation angle window (3), the synchronization of the feed movement profile (5) with the rotation of the crank drive (4) is canceled and the feed movement profile (5) is moved to the end independently of the rotation of the crank drive (4). This mode of operation reduces the maximum torque requirement of the feed axes for servo feeds operated angularly synchronously with the crank drive of the press plunger, so that smaller and therefore more cost-effective servo drives can be used or more load can be moved with a given servo drive.

A method for operating a punching press with a press plunger driven by a crank drive, which operates in a machining zone of the punching press against a stationary clamping plate, and with a servo feed apparatus for intermittently feeding a band of material to be processed to the machining zone. In punching mode, the press plunger is moved back and forth by the crank drive between a first movement dead point (0), in which the press plunger is at maximum distance from the clamping plate, and a second movement dead point (180), in which the press plunger is at minimum distance from the clamping plate. In the process, the material band is pushed by the servo feed apparatus around the first movement dead point (0) in a first rotation angle window (3) of the crank drive by a certain length into the machining zone and processed in a second rotation angle window during the feed pauses. The feed movement of the servo feed drive takes place according to an electronically defined feed movement profile (5), which is followed in the first rotation angle window (3) in an electronically synchronized manner to the rotation of the crank drive (4). When a press stop (6) is triggered in the first rotation angle window (3), the synchronization of the feed movement profile (5) with the rotation of the crank drive (4) is canceled and the feed movement profile (5) is moved to the end independently of the rotation of the crank drive (4). This mode of operation reduces the maximum torque requirement of the feed axes for servo feeds operated angularly synchronously with the crank drive of the press plunger, so that smaller and therefore more cost-effective servo drives can be used or more load can be moved with a given servo drive.

A press machine includes a press frame having first and second portions, a crankshaft, a crankshaft, a ram, a ram drive mechanism supported by the first portion of the press frame at a primary force application location, a ram guide linearly guiding the ram, and supported by the second portion of the press frame at a ram guide location; and a working tool including an upper tool section and a lower tool section configured for the processing of a workpiece. The upper tool section is fixedly attached to the ram and the lower tool section is fixedly attached to the press frame at a lower tool location. The primary force application location has a first working position during the processing of the workpiece, and a second resting position when the workpiece is not being processed. The ram guide location has a first working position during the processing of the workpiece, and a second resting position when the workpiece is not being processed. The difference between the working position and the resting position of the ram guide location is less than the difference between the working position and the resting position of the primary force application location.

A press machine includes a press frame having first and second portions, a crankshaft, a crankshaft, a ram, a ram drive mechanism supported by the first portion of the press frame at a primary force application location, a ram guide linearly guiding the ram, and supported by the second portion of the press frame at a ram guide location; and a working tool including an upper tool section and a lower tool section configured for the processing of a workpiece. The upper tool section is fixedly attached to the ram and the lower tool section is fixedly attached to the press frame at a lower tool location. The primary force application location has a first working position during the processing of the workpiece, and a second resting position when the workpiece is not being processed. The ram guide location has a first working position during the processing of the workpiece, and a second resting position when the workpiece is not being processed. The difference between the working position and the resting position of the ram guide location is less than the difference between the working position and the resting position of the primary force application location.

The die cushion force setting apparatus according to an aspect of the present invention allows die cushion forces (component forces) acting on plural driving shafts to be set easily, makes it easy to apply strong or weak die cushion forces to a complex-shaped drawn part in a plane of a cushion pad, and provides a smooth die cushion force distribution. An operator manually enters a total die cushion force, axial component force of a left front hydraulic cylinder, and center-of-force position by operating an input device. Based on the information entered via the input device, the numerical computing device B1 calculates axial component forces of three hydraulic cylinders through numerical computations. The one axial component force thus entered and three axial component forces thus computed numerically are set as the axial component forces of four hydraulic cylinders.

The die cushion force setting apparatus according to an aspect of the present invention allows die cushion forces (component forces) acting on plural driving shafts to be set easily, makes it easy to apply strong or weak die cushion forces to a complex-shaped drawn part in a plane of a cushion pad, and provides a smooth die cushion force distribution. An operator manually enters a total die cushion force, axial component force of a left front hydraulic cylinder, and center-of-force position by operating an input device. Based on the information entered via the input device, the numerical computing device B1 calculates axial component forces of three hydraulic cylinders through numerical computations. The one axial component force thus entered and three axial component forces thus computed numerically are set as the axial component forces of four hydraulic cylinders.

A processing machine for performing a bending operation on a workpiece includes a die, a punch movable in a first direction for pressing the workpiece against the die, a slide member movable in a second direction perpendicular to the first direction, a first cam device that moves the punch toward the die for deforming the workpiece when being actuated by movement of the slide member, a second cam device that moves the punch for pressing a surface of the workpiece when being actuated by movement of the slide member. The pressure angle of the second cam device is smaller than a pressure angle of the first cam device. The processing machine further includes a drive member configured to move the slide member such that the second cam device is actuated after the first cam device is actuated.

A drive device (10) for a forming machine (11) includes a hypocycloid gear assembly (20) having an eccentric gear (23), a stationary annulus gear (24) and a planetary gear system (28). The planetary gear system (28) includes an orbiting gear (29) orbiting and rolling in an annulus gear (24). The orbiting gear (29) is connected to at least one first planetary gear (35). On the first planetary gear (35), a first planetary gear equalization mass (m.sub.2) is disposed diametrically opposite an output bearing. At least one first eccentric gear equalization mass (m.sub.3) is arranged on the eccentric gear (23). The first eccentric gear equalization mass (m.sub.3) is arranged diametrically opposite, relative to a planetary gear axis (PA) about which the planetary gear system (28) rotates. The resultant forces and torques acting on the annulus gear (24) can at least be reduced by the equalization masses.