Method for operating a press with an underneath drive and press operated according thereto

Abstract

A method and a press are proposed for an energy-efficient drive of a press (1) with a bottom drive, in which a drive device (2) disposed in a bottom section (3), a plunger (1.1) executing a stroke (H) and receiving an upper tool part (1.2) with at least one acting tie rod (2.1.2) of a drive train (2.1) are provided and the upper tool part (2.1) corresponding to a bottom tool part (3.2) disposed in the bottom section (3) machines or forms a work piece (5). The drive device (2) is operated by at least one motor (2.1.1) and by way of a control and regulation device (4) connecting the motor (2.1.1) and the drive train (2.1). Each drive train (2.1) can be operated by its own motor (2.1.1). When using a drawing device with a holder (3.3.1), it is operated in the change and during at least a partial path of the respective stroke (H) by the drive train (2.1) while observing a shaft-type free space (3.2) provided in the bottom section (3) in a coupled or decoupled manner by a releasable rotatory or translational active connection.

Claims

1. A method for operating a press, wherein a work piece is machined or formed by: a drive device arranged in a bottom section, and at least one plunger configured to execute a stroke and to receive at least one upper tool part which comprises at least one acting tie rod of at least one drive train, the at least one upper tool part corresponding to at least one bottom tool part being arranged in the bottom section, and a drawing device comprising a holder, the method comprising: driving the drive device by at least one motor as a linear and/or a rotary direct drive; and when using the drawing device, operating a path of the drive device so that the drive device is couplable or decouplable from a complete stroke of the at least one plunger so that the stroke of the at least one plunger and the drawing device are always operated in a closed force flow; and operating the at least one drive train so that the at least one drive train is coupled or decoupled to the drawing device by a releasable active connection which is at least one of rotatory and translational in a change of a respective stroke.

2. The method as recited in claim 1, wherein the at least one drive train is operated by a control and regulation device which connects to the least one motor.

3. The method as recited in claim 1, wherein each of the at least one drive train is operated by a respective one of the at least one motor.

4. The method as recited in claim 1, wherein the at least one drive train is operated while keeping a shaft-type free space arranged in the bottom section.

5. The method as recited in claim 1, wherein the at least one drive train operates the drawing device.

6. The method as recited in claim 1, wherein, the at least one drive train is coupled to the drawing device during at least a partial path of a downward stroke, and the at least one drive train and is decoupled from the drawing device during at least a partial path of an upward stroke.

7. The method as recited in claim 6, wherein the at least one drawing device is operated so that it does not reproduce or follow a path of a complete stroke of the at least one plunger.

8. The method as recited in claim 1, wherein, the active connection is between at least one of drive elements of the drive train and at least one of elements of the drawing device so as to act as a carrier unit with an intermediate level or a pressure cheek or an intermediate level and the pressure cheek or only the pressure cheek and is operated by at least one first force-generating means which is closed or released in the change by a positive or frictional or force-fit engagement, and a position of the carrier unit is varied during a forming of the work piece.

9. The method as recited in claim 1, wherein, the active connection is between at least one of drive elements of the drive train and at least one of elements of the drawing device so as to act as a carrier unit with an intermediate level or a pressure cheek or an intermediate level and the pressure cheek or only the pressure cheek and is operated by at least one first force-generating means which is closed or released in the change by a positive or frictional or force-fit engagement, and a position of the carrier unit relative to the holder is not varied.

10. The method as recited in claim 1, wherein the active connection is closed or released depending on at least one of values or gradients of forming forces, speed or paths to be transmitted, or of one of positions of work steps of a forming, of drive elements, of positions of the at least one plunger, of the holder, of the carrier unit or of a speed.

11. The method as recited in claim 8, wherein, a) the plunger operated downward from or from before or from after a top dead center is moved toward the holder located in an upper initial position and the holder in an active connection with the carrier unit is moved downward immediately before an impact of a hit of the at least one plunger connected to the upper tool part acting onto the holder, so that, when the upper tool part impacts on the holder, the holder is already moved in a pre-accelerated manner up to a first position so as to reduce an impact load, b) after the upper tool part has impacted on the holder, closing the active connection between at least one of the elements of the drive train and the intermediate level or the pressure cheek or the intermediate level and the pressure cheek, and moving these elements up to a bottom end position of the holder, and the at least one plunger, with the upper tool part, are moved together up to its bottom dead center and to a second position, and c) releasing the active connection between at least one of the elements of the drive train and the drawing device with the intermediate level or the pressure cheek or the intermediate level and the pressure cheek once the at least one plunger has reached its bottom dead center.

12. The method as recited in claim 8, wherein at least one of the following sequences is applied: a) operating the at least one plunger in an upward stroke so that it is coupled with the upper tool part and the intermediate level or the pressure cheek or the intermediate level and the pressure cheek after the bottom end position, b) releasing the active connection of the holder either with the intermediate level or the pressure cheek or the intermediate level and the pressure cheek after the bottom end position of the holder, c) separately operating the at least one plunger with the upper tool part and the intermediate level or the pressure cheek or the intermediate level and the pressure cheek and the holder toward their upper initial position, and d) operating the at least one plunger with the upper tool part so that it is decoupled from the intermediate level or the pressure cheek or the intermediate level and the pressure cheek starting from a third position immediately before reaching the upper initial position of the holder.

13. The method as recited in claim 1, wherein, a) first, when the at least one plunger is in an initial position corresponding to a top dead center and a pressure cheek and the holder are in an upper initial position, a first force-generating piston rod is partially extended in a first force-generating cylinder of a first force-generating means and the first force-generating cylinder is in an intermediate position, b) when the at least one plunger initiates a downward movement, an engagement occurs by way of the at least one acting tie rod with a first wheel of a gear of a rotatory coupling comprising a second wheel, wherein the second wheel comprises an eccentric coupling element which acts via a positive, frictional or force-fit engagement so as to allow for a movement relative to the second wheel, via a connecting rod eccentrically linked to the first wheel, and the holder thereby remains in its top initial position, wherein a bottom chamber in the first force-generating cylinder is loaded with a controlled or regulated medium, so that the first force-generating cylinder extends according to a movement of the first wheel and the second wheel and the holder thus remains in the top initial position, c) when the holder begins to pre-accelerate toward a first position, a volume flow of the controlled or regulated medium to the bottom chamber of the first force-generating cylinder is reduced shortly before the at least one plunger impacts on the holder so as to initate a downward movement of the holder independently of whether the controlled or regulated medium is correspondingly supplied into an upper chamber or not, d) the at least one plunger in the first position then impacts on the holder so as to generate a pressure in the bottom chamber of the first force-generating cylinder and to transmit an action (force) of the first force-generating cylinder via the pressure cheek to the holder, which rests on the upper tool part moving downward, and e) the work piece to be machined is clamped and formed in an energy-saving manner by a closed force flow, starting at the first force-generating cylinder, continuing along the pressure cheek, the holder, the upper tool part, the at least one plunger, the at least one acting tie rod, the connecting rod, the first wheel, and the second wheel, wherein a forming process occurs up to a bottom dead center in the first force-generating cylinder by an active control/regulation of the pressure, independently of whether a volume of the controlled or regulated medium is supplied or not.

14. The method as recited in claim 13, wherein the stroke (H) of the at least one plunger, a stroke (h) of the holder, and a stroke (hZyl) in the first force-generating cylinder are controlled according to a relation hZyl?H?h, in accordance with an eccentricity (E) E=H/2 existing in the second wheel in connection with the eccentric coupling element acting by a positive, frictional or force-fit engagement, so that, in a combination of the first force-generating cylinder with the eccentric coupling element of the second wheel, the stroke of the first force-generating cylinder, now serving only for a force generation, becomes relatively small and a length of a connection of the first force-generating means between the pressure cheek and the eccentric coupling element can be kept smaller than a length of the connecting rod.

15. The method as recited in claim 14, wherein, in order to compensate for deviations caused by an operation or a structure and irregular movements of a carrier unit, an intermediate level, the pressure cheek, or the holder, the controlled or regulated medium is selectively introducable into the first force-generating means for the movement of the at least one plunger.

16. The method as recited in claim 15, wherein, immediately before the holder reaches an upper initial position, a supply of the controlled or regulated medium into the first force-generating cylinder is controlled or regulated so as to generate relative movements in the first wheel via the eccentric coupling element or in the first force-generating cylinder for a temporarily stationary upper initial position the holder.

17. The method as recited in claim 16, wherein, via an externally induced force, the carrier unit of the drawing device is moved into the upper initial position and the active connection is formed by the eccentric coupling element immediately before reaching the first position.

18. The method as recited in claim 17, wherein, when the holder begins to move downward, the work piece is clamped between the holder and the upper tool part and is moved in an energy-saving manner together with the at least one plunger to the bottom dead center and then back to the upper initial position.

19. The method as recited in claim 13, wherein a first force-inducing element supports the downward movement of the holder and of the carrier unit and the coupling element by a small stroke.

20. The method as recited in claim 19, wherein, a) the holder remains in a bottom end position after a release of the holder from the upper tool part has occurred in the bottom dead center of the at least one plunger, and b) the at least one plunger is then moved upwards, wherein correspondingly, supplied controlled or regulated medium can directly or indirectly flow from the bottom chamber into the upper chamber in order for the pressure cheek to remain in position, wherein, c) in step a), a matched small volume of the controlled or regulated medium is provided to release the holder, the work piece being released from the bottom tool part in a delayed speed-up, and the pressure cheek being moved together with the holder to the upper initial position.

21. The method as recited in claim 20, wherein after a starting position of an intermediate level or the pressure cheek or the intermediate level and the pressure cheek at about ? of the stroke of the at least one plunger and with the at least one acting tie rod moved downward, a tie of the at least one acting tie rod impacts a locking unit piston of a locking unit which is connected with the intermediate level or the pressure cheek or the intermediate level and the pressure cheek, a volume of a medium enclosed in a locking unit cylinder is discharged in a controlled manner, the intermediate level or the pressure cheek or the intermediate level and the pressure cheek are moved downwards and pre-accelerated by a pressure thus built up, the intermediate level or the pressure cheek or the intermediate level and the pressure cheek are held against a gravitational acceleration and against an action of the locking unit by an action of the first force-generating means, the volume enclosed in a bottom chamber of the first force-generating means cylinder is thus reduced, the locking unit piston enters the locking unit cylinder and prepares the positive, frictional and/or force-fit connection with the at least one acting tie rod and the positive, frictional and/or force-fit connection with the at least one acting tie rod is then established via the locking unit cylinder, in the sequence toward the bottom dead center of the at least one plunger, pressure is built up in a second force-generating cylinder of at least one second force-generating means, by impinging a second force-generating piston of the second force-generating means with pressure against a direction of a movement of the intermediate level or the pressure cheek or the intermediate level and the pressure cheek in a regulated manner, a first force-generating means piston of the first force-generating means is moved downward during the process, the second force-generating means piston is relieved of the pressure in the bottom dead center and the active connection of the holder with the intermediate level or with the pressure cheek or with the intermediate level and the pressure cheek is released after the bottom end position of the holder, and in the return sequence to the initial position, the at least one acting tie rod is moved freely in the locking unit so that the intermediate level or the pressure cheek or the intermediate level and the pressure cheek are held in the bottom position by the pressure from the upper chamber of the first force-generating means cylinder and then moved to the initial position.

22. The method as recited in claim 21, wherein the carrier unit is pre-accelerated by a value which is reduced by a value of a speed of the at least one plunger.

23. The method as recited in claim 22, wherein the value of the speed of the carrier unit is 80% of the speed of the at least one plunger.

24. The method as recited in claim 23, wherein a counterforce required for the forming process is applied on at least one floor comprising the intermediate level and/or the pressure cheek of the carrier unit by an energy-saving force flow which is implemented and closed without a power loss by the first force-generating means through its direct active connection with the intermediate level and/or the pressure cheek of the carrier unit by a positive or frictional or force-fit active connection with the at least one acting tie rod, the at least one plunger, the upper tool part, the work piece, and the holder.

25. The method as recited in claim 24, wherein, for a removal of the work piece from the bottom tool part, the holder is lifted by the first force-generating means or by second force-generating means or by a temporary positive or frictional or force-fit active connection.

26. The method as recited in claim 20, wherein the control and regulation device is used for recording, evaluating and controlling/aligning at least one of the values or parameters of at least one of the dimensions or gradients, of forming forces, counterforces or a speed to be transmitted, or of one of the positions of the work steps of forming, of the drive elements, of the positions of the at least one plunger, of the holder, or of the carrier unit, so as to change from a closed active connection to a released active connection or vice versa.

27. A press with a bottom drive, the press comprising: a drive device as a linear and/or a rotary direct drive arranged in a bottom section; a plunger configured to execute a stroke and to receive an upper tool part which comprises at least one acting tie rod of at least one drive train, the upper tool part corresponding to a bottom tool part arranged in the bottom section; at least one motor as a linear and/or a rotary direct drive which is configured to drive the drive device; and a drawing device comprising a holder, wherein, the at least one drive train is configured to be operated so that the at least one drive train is coupled or decoupled to the drawing device by a releasable active connection which is at least one of rotatory and translational in a change of a respective stroke.

28. The press as recited in claim 27, further comprising: a control and regulation device which is configured to connect the at least one drive train and the at least one motor.

29. The press as recited in claim 27, wherein each of the at least one drive train is associated with one of the at least one motor.

30. The press as recited in claim 27, further comprising: a shaft-type free space arranged in the bottom section.

31. The press as recited in claim 27, further comprising: a drawing device, wherein, the at least one drive train is connected to the drawing device.

32. The press as recited in claim 27, wherein, the at least one drive train is coupled to the drawing device during at least a partial path of a downward stroke, and the at least one drive train is decoupled from the drawing device during at least a partial path of an upward stroke.

33. The press as recited in claim 27, wherein a path of the drawing device is at least partially phase-delayed or is less than a path of a complete stroke of the plunger.

34. The press as recited in claim 27, wherein the drawing device comprises a carrier unit which is connected to the at least one drive train in a couplable or decouplable manner in a change via the rotatory or translational active connection by a positive or frictional or force-fit engagement in a causative variable or not variable position relative to the bottom section.

35. The press as recited in claim 27, further comprising: at least one first force-generating means which is connected above or below to the carrier unit, the at least one first force-generating means being configured to allow for a relative position of the carrier unit in the bottom section.

36. The press as recited in claim 35, further comprising: at least a second force-generating means which is connected to the carrier unit.

37. The press as recited in claim 36, wherein the carrier unit comprises an intermediate level or a pressure cheek or the intermediate level and the pressure cheek or only the pressure cheek.

38. The press as recited in claim 37, wherein the pressure cheek is arranged above or below the intermediate level and is configured to be drivable either separately or with at least one of the at least one drive train.

39. The press as recited in claim 38, wherein the pressure cheek is arranged in the bottom section above the intermediate level.

40. The press as recited in claim 37, wherein, i. the rotatory or translational active connection comprises at least one first force-generating means cylinder of the first force-generating means, whose first force-generating means piston rod is connected with the pressure cheek and whose first force-generating means piston crown is connected with the drive device or vice versa, and ii. the at least one first force-generating means cylinder is a double-acting cylinder which is configured to an element of the at least one drive train with an acting force or a change of force and a relative position of the pressure cheek by a pressure contact of the first force-generating means piston rod or the first force-generating means piston crown.

41. The press as recited in claim 40, wherein, the drive device comprises a force and path inducing first wheel, and the first force-generating means piston crown is eccentrically hinged to the force and path inducing first wheel for at least one of regulated or controlled sequences of motion sequences, of a pre-acceleration of the pressure cheek, of a pressure application, or of a force generation.

42. The press as recited in claim 41, further comprising: a second wheel; and a rotary coupling, wherein, the first force-generating piston crown is connected via the second wheel and the force and path inducing first wheel, and the second wheel and the force and path inducing first wheel form a gear of the rotatory coupling, with the drive device for at least one sequence of the regulated or controlled motion sequences, of the pre-acceleration of the pressure cheek, of the pressure application, or of the force generation.

43. The press as recited in claim 42, wherein the at least one acting tie rod comprises a connecting rod which is eccentrically hinged to the force and path inducing first wheel.

44. The press as recited in claim 43, wherein the second wheel comprises an eccentric coupling element which is configured to allow for a movement relative to the second wheel and which acts via a positive, frictional or force-fit engagement.

45. The press as recited in claim 44, wherein the stroke (H) of the at least one plunger, a stroke (h) of the holder, and a stroke (hZyl) in the at least one first force-generating means cylinder are implementable according to a relation hZyl?H?h, in accordance with an eccentricity (E) E=H/2 existing in the second wheel in connection with the eccentric coupling element, wherein, in the combination of the at least one first force-generating means cylinder with the eccentric coupling element of the second wheel, the stroke of the at least one first force-generating means cylinder now serving only for the force generation is small, and a length of a connection of the first force-generating means between the pressure cheek and the eccentric coupling element is implementable so as to be smaller than a length of the connecting rod.

46. The press as recited in claim 45, further comprising: a translational coupling, wherein, the drive device comprises at least one auxiliary tie rod, and the rotatory or translational active connection of the intermediate level or the pressure cheek or the intermediate level and the pressure cheek occurs via the translational coupling with at least one of the tie rods or the at least the auxiliary tie rod.

47. The press as recited in claim 46, further comprising: a) an area which is limited by a tie, a shoulder and by a reduced diameter of the at least one acting tie rod or of the auxiliary tie rod; b) at least one locking unit which is connected with the intermediate level or the pressure cheek or with the intermediate level and the pressure cheek with a locking unit piston and a locking unit cylinder comprising a first chamber and a second chamber as a housing and a locking element; and c) an upper chamber and a bottom chamber of the at least one first force-generating means cylinder of the first force-generating means.

48. The press as recited in claim 47, wherein the first force-generating means is implemented as at least one coupling connecting rod which is configured to connect the carrier unit with the drive device.

49. The press as recited in claim 48, wherein the coupling connecting rod comprises a telescopic extension mechanism which is couplable by a positive, friction or force-fit engagement.

50. The press as recited in claim 49, wherein the carrier unit comprises a parallel and linear guide with the intermediate level or the pressure cheek or the intermediate level and the pressure cheek or only the pressure cheek a shaft-type free free space of the bottom section.

51. The press as recited in claim 50, wherein the rotatory coupling of the at least one drive train of the drive device is arranged in the shaft-type free space or outside thereof.

52. The press as recited in claim 51, wherein the control and regulation device is further configured to transmit a changing or force/path-related control/regulation of the path or force during an operating process.

53. The press as recited in claim 52, wherein a closed force flow for an energy-saving operating process runs through the first force-generating means, by way of the intermediate level or the pressure cheek or the intermediate level and the pressure cheek, the rotatory or translational active connection with each of the at least one drive train, the at least one plunger, the upper tool part, the work piece, and the holder.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings

(2) FIG. 1 shows a graphical representation of the principle of the process of the method according to the invention with the function of an interaction of the plunger with the drawing device that is novel with regard to the prior art,

(3) FIG. 2 shows the schematic representation of a constructional variant of the press according to the invention in a front view,

(4) FIG. 2.1 shows the schematic view of the modified force flow according to the invention as compared to the prior art,

(5) FIG. 3 shows a constructional variant of the press according to the invention with a first embodiment of a translational coupling,

(6) FIG. 4 shows a constructional variant of the press according to the invention with a second embodiment of a translational coupling,

(7) FIG. 5 shows a constructional variant of the press according to the invention with a third embodiment of a translational coupling,

(8) FIG. 6.1 shows a representation of a constructional variant of the press according to the invention with the embodiment of a rotatory coupling in the top dead center OT of the plunger,

(9) FIG. 6.2 shows the constructional variant according to FIG. 6.1 in a motion phase of the plunger toward the bottom dead center UT of the plunger,

(10) FIG. 7 shows a construction variant of the press according to the invention with a first hybrid variant of a rotatory and translational coupling using a coupling connecting rod and

(11) FIG. 7.1 shows a construction variant of the press according to the invention with a second hybrid variant of a rotatory and translational coupling using a coupling connecting rod.

WAYS OF IMPLEMENTING THE INVENTION

(12) FIG. 1 illustrates the graphical representation of coordinates of a path (m) and a crank angle (grd) of a curve of a plunger course and the principle of the method process according to the invention with pre-acceleration (in contrast to the mentioned method process without pre-acceleration according to the prior art) in the context of the new function of strokes H of a plunger course with a stroke h of a holder 3.3.1 (e.g., FIG. 2) of a drawing device 3.3 (e.g., FIG. 2). A plunger 1.1 (e.g., FIG. 2) operated in a downward stroke H from or from before or from after a top dead center OT onto a holder 3.3.1 (e.g., FIG. 2) movable in an upper initial position O, a first position A, toward which the holder 3.3.1 (e.g., FIG. 2), which is moveable downward in a stroke h, is pre-accelerated, namely immediately before the impact of a hit of the plunger 1.1 (e.g., FIG. 2) connected to an upper tool part 1.2 (e.g., FIG. 2) acting on it, a common active connection between one of the elements of drive trains 2.1 (e.g., FIG. 2) and an intermediate level 3.4 (e.g., FIG. 2) or a pressure cheek 3.5 (e.g., FIG. 3), operated in a closed manner toward a bottom dead center UT of the plunger 1.1 (FIG. 2) and toward a bottom end position U of the holder 3.3.1 (FIG. 2) as well as toward a second position B referred to as a hold-down position, namely after the upper tool part 1.2 (FIG. 2) has impacted on the holder 3.3.1 (FIG. 2); a releasable active connection between at least one of the elements of the drive trains 2.1 (FIG. 2) and of the drawing device 3.3 (e.g., FIG. 2) with the intermediate level 3.4 (FIG. 2) or the pressure cheek 3.5 (FIG. 3) or the intermediate level 3.4 (FIG. 2) and the pressure cheek 3.5 (FIG. 3), optionally referred to as release stroke, after the plunger 1.1 (FIG. 2) has reached its bottom dead center UT, can be gathered from the curve progressions in FIG. 1.

(13) It can further be gathered from FIG. 1 with reference e.g., to FIG. 2 and FIG. 3, that the upwards operated plunger 1.1 can be operated so that it is coupled with the upper tool part 1.2 and the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 after the bottom end position U, the active connection of the holder 3.3 either with the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 is released after the bottom end position U of the holder 3.3 and a so called delayed speed-up at least of the pressure cheek 3.5 for example can occur, the plunger 1.1 with the upper tool part 1.2 and the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5, and the holder 3.3 can be separately operated toward an upper initial position O, the plunger 1.1 with the upper tool part 1.2 can be operated so that it is decoupled from the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 starting from a third position C immediately before reaching the upper initial position O of the holder 3.3.

(14) According to this visual representation, the method can be understood in principle as follows:

(15) In a press 1 implementable according to FIG. 2, FIG. 2.1, FIG. 3, FIG. 4, FIG. 5, FIG. 6.1, FIG. 6.2, FIG. 7 and/or FIG. 7.1, which has a drive device 2 disposed in a bottom section 3 and connected by way of drive trains 2.1 and at least one, plunger 1.1 executing the stroke H and receiving the upper tool part 1.2 with at least one tie rod 2.1.2 acting e.g., on its respectively outer end,

(16) which forms a work piece 5 with the at least one upper tool part 1.2 corresponding to at least one bottom tool part 3.2 disposed in the bottom section, by means of a drawing device 3.3 with a holder 3.3.1 for the work piece 5 to be machined, the motion sequence of the drawing device 3.3 and each drive train 2.1 of the drawing device 3.3 is operated in a coupled and decoupled manner in the change of the respective stroke H by means of a releasable active connection while keeping a free space 3.3.2 in the bottom section 3.

(17) Thereby, during at least a partial travel of the downward stroke H, the drive train 2.1 is operated so that it is coupled to the drawing device 3.3 and during a partial travel of the upward stroke H, the drive train 2.1 is operated so that it is decoupled from the drawing device 3.3 and the drawing device 3.3 is thereby operated so that it does not reproduce or follow the path of the complete plunger stroke. This means that the path of the drawing device 3.3 with the holder 3.3.1 according to the stroke h is smaller than the path of the plunger 1.1 with the stroke H.

(18) In the course of the stroke H, the active connection between at least one of drive elements of the drive train 2.1 and at least one of elements of a drawing device acting as a carrier unit with the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 or only the pressure cheek 3.5 of the drawing device 3.3 and operated by at least one first force-generating means 3.6, is alternately opened or closed by a force-fit or positive engagement and the position of the carrier unit during machining of the work piece 5 is varied.

(19) Depending on at least one of the values or gradients of forming forces and paths to be transmitted, of one of the positions of the work steps of forming, of the elements of the drive trains 2.1, of the positions of the plunger 1.1, of the holder 3.3.1, of the carrier unit or of a speed, the active connection is closed or released, said functions being implemented by the control and regulation device 4.

(20) The basic process of the method is completed in such a sequence of steps that a) the plunger 1.1 operated downward from or from before or from after a top dead center OT is moved toward a holder 3.3.1 located in an upper initial position O and the holder 3.3.1 in an active connection with the carrier unit is moved downward directly before the impact of a hit of the plunger 1.1 connected to the upper tool part 1.2 acting onto the holder 3.3.1, so that when the upper tool part 1.2 impacts on the holder 3.3.1, the holder is already moved in a pre-accelerated manner up to a first position A (FIG. 1) and the impact load is thus reduced and b) after the upper tool part 1.2 has impacted on the holder 3.3.1, the active connection between at least one of the elements of the drive trains 2.1 and the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 is closed and these elements are moved up to a bottom end position U (FIG. 1) of the holder 3.3.1 and the plunger 1.1 with the upper tool part 1.2 are moved together up to its bottom dead center UT (FIG. 1) and to a second position B (FIG. 1), wherein c) alternately, the active connection between at least one of the elements of the drive trains 2.1 and the drawing device 3.3 with the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 is released together, once the plunger 1.1 has reached its bottom dead center UT (FIG. 1).

(21) The method thereby integrates at least one of the following sequences: the upwards operated plunger 1.1 is operated so that it is coupled with the upper tool part 1.2 and the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 after the bottom end position U, the active connection of the holder 3.3.1 either with the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 is released after the bottom end position U of the holder 3.3.1, the plunger 1.1 with the upper tool part 1.2 and the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5 and the holder 3.3 are operated separately toward their upper initial position O, the plunger 1.1 with the upper tool part 1.2 is operated so that it is decoupled from the intermediate level 3.4 or the pressure cheek 3.5 or the intermediate level 3.4 and the pressure cheek 3.5, starting from a third position C (FIG. 1) immediately before reaching the upper initial position O of the holder 3.3.

(22) The method is preferably implemented with a rotatory active connection of the press 1 shown in FIG. 6.1 and FIG. 6.2. The process steps here occur in such a manner that 1. first, when the plunger 1.1 is in an initial position corresponding to the top dead center OT (FIG. 1) and the pressure cheek 3.5 and holder 3.3.1 are in an upper initial position O (FIG. 1), a piston rod 3.6.1.3 is partially extended in a cylinder 3.6.1 of the first force-generating means 3.6 and the cylinder 3.6.1 is in an intermediate position, 2. when the plunger 1.1 initiates a downward movement, an engagement occurs by way of the tie rod 2.1.2 with a first wheel 2.3.1 of a gear comprising a second wheel 2.3.2, wherein said second wheel 2.3.2 comprises an eccentric coupling element 2.3.2.1 acting by a positive or force-fit engagement and allowing for a movement relative to the second wheel 2.3.2, by means of a connecting rod 2.1.3 eccentrically linked to the first wheel 2.3.1, and the holder 3.3.1 thereby remains in its top initial position O (FIG. 1), wherein a bottom chamber 3.6.1.2 in the cylinder 3.6.1 is loaded with a controlled or regulated medium, so that the cylinder 3.6.1 extends according to the movement of the pair of wheels 2.3.1, 2.3.2 and the holder 3.3.1 thus remains in the top initial position O (FIG. 1), 3. when the holder 3.3.1 begins to pre-accelerate toward the first position A (FIG. 1), the volume flow of the medium to the bottom chamber 3.6.1.2 of the cylinder 3.6 is reduced shortly before the plunger 1.1 impacts on the holder 3.3.1, and a downward movement of the holder 3.3.1 is thus initiated, independently of whether medium is correspondingly supplied into an upper chamber 3.6.1.1 or not, 4. the plunger 1.1 in the first position A (FIG. 1) then impacts on the holder 3.3.3 and a pressure is generated in the bottom chamber 3.6.1.2 of the cylinder 3.6.1 and an action by means of the force of the cylinder 3.6.1 is transmitted by way of the pressure cheek 3.5 to the holder 3.3.1, which rests on the upper tool part 1.2 moving downward, and 5. the work piece 5 to be machined is clamped and formed in an energy-saving manner by means of a closed force flow K visible in FIG. 2. 1 to the right of the center line, starting at cylinder 3.6.1, continuing along the pressure cheek 3.5, the holder 3.3.1, the upper tool part 1.2, the plunger 1.1, the tie rods 2.1.2, the connecting rods 2.1.3 as well as the first wheel 2.3.1 and the second wheel 2.3.2as shown in FIGS. 6.1 and 6.2, wherein the forming process occurs up to the bottom dead center UT (FIG. 1) in the cylinder 3.6.1 by active control/regulation of the pressure, independently of whether volume of the medium is supplied or not.

(23) The closed force flow K essential to the invention as shown in FIG. 2.1 to the right of the center line illustrates more specifically the beneficial effects created by the invention as compared to the costly force flow in terms of energy and components shown to the left of the center line according to the prior art as analyzed in the introduction.

(24) Thus, the drawing device 3.3 is operated so that it is couplable or decouplable with the complete stroke H of the plunger 1.1, wherein the stroke H of the plunger 1.1 and the drawing device 3 are always operated in a closed force flow.

(25) Due to the modified method sequences and constructive changes in the press with a bottom drive, the stroke H (FIG. 1) of the plunger 1.1, the stroke h (FIG. 1) of the holder 3.3.1 and a stroke H.sub.Zyl (FIG. 6.1 and FIG. 6.2) in the cylinder 3.6.1 are now controlled according to the relation h.sub.Xyl?H-h, in accordance with an eccentricity E, E=h/2 (FIG. 6.1 and FIG. 6.2), existing in the second wheel 2.3.2 in conjunction with the eccentric coupling element 2.3.2.1 acting by positive, frictional and/or force-fit engagement. In the combination of the cylinder 3.6.1 with the eccentric coupling element 2.3.2.1 of the second wheel 2.3.2, the stroke h.sub.Zyl of the cylinder 3.6.1, which serves only for building up a force, is relatively small. A length l.sub.1 (FIG. 6.1 and FIG. 6.2) of a connection of the first force-generating means 3.6 between the pressure cheek 3.5 and the eccentric coupling element 2.3.2.1 can thus be advantageously kept significantly smaller than a length 12 (FIG. 6.1 and FIG. 6.2) of the connecting rod 2.1.3.

(26) In order to compensate for deviations caused by the operation or the structure and irregular movements of the carrier unit, the intermediate level 3.4, the pressure cheek 3.5 or the holder 3.3.1 for the movement of the plunger 1.1, medium can be selectively introduced into the first force-generating means 3.6.

(27) Immediately before the holder 3.3.1 reaches the upper initial position O (FIG. 1), the supply of the medium into the cylinder 3.6.1 is controlled or regulated for generating relative movements in the first wheel 2.3.1 by means of the eccentric coupling element 2.3.2.1 or in the cylinder 3.6.1 for a temporarily stationary upper initial position O the holder 3.3.1.

(28) When the holder 3.3.1 begins moving downward, the work piece 5 is clamped between the holder 3.3.1 and the upper tool part 1.2 and moved together with the plunger 1.1 in an energy-saving manner toward the bottom dead center UT and then moved back to the upper initial position O. The downward movement is thereby supported by the force-generating first means 3.6 with a relatively small stroke.

(29) The method corresponding to the rotatory active connection ends by 1. the holder 3.3.1 remaining in the bottom end position U after a release of the holder 3.3.1 from the upper tool part 1.2 has occurred in the bottom dead center UT of the plunger 1.1, 2. the plunger 1.1 being then moved upwards, wherein correspondingly supplied medium can directly or indirectly flow from the bottom chamber 3.6.1.2 into the upper chamber 3.6.1.1 in order for the pressure cheek 3.5 to remain in position, wherein 3. for step (a) an adjusted volume of the medium being provided for an optimized motion sequence and after releasing the holder 3.3.1 the volume of the medium in a mode of a delayed speed-up, the pressure cheek 3.5 is lifted to the upper initial position O.

(30) The specific steps and alternative implementation of a translational active connection with the phases I, II, III in a first implementation variant are explained as follows based on FIG. 3: a) After an initial position of the intermediate level 3.4 at approximately ? of the stroke H (FIG. 1) of the plunger 1.1 (FIG. 2) shown in phase I and with the tie rod 2.1.2 moving downward, in phase II, a tie 2.1.2.1 of the tie rod 2.1.2 impacts on a piston 3.4.2 of a locking unit 3.4.1 connected to the intermediate level 3.4, a volume of a medium enclosed in a cylinder 3.4.3 is discharged in a controlled manner, the intermediate level 3.4 is moved downward and pre-accelerated by means of a pressure thus built up, the intermediate level 3.4 is held by the action of the first force-generating element 3.6 against the gravitational acceleration and against the action of the locking unit 3.4.1, the volume enclosed in a bottom chamber 3.6.1.2 of the cylinder 3.6.1 of the force-generating means 3.6 is thereby reduced, the piston 3.4.2 of the locking unit 3.4.1 penetrates into the cylinder 3.4.3 of the locking unit 3.4.1, whereby the connection with the tie rod 2.1.2 is prepared and the connection with the tie rod (2.1.2) is then created by means of the cylinder 3.4.3, b) in the operating sequence toward the bottom dead center UT (FIG. 1) of the plunger 1.1, a pressure is built up in a cylinder 3.7.1 of a second force-generating means 3.7 by pressurizing a piston 3.7.2 of the second force-generating means 3.7 against the direction of movement of the intermediate level 3.4 in a regulated manner, during the operating sequence, the piston 3.6.2 of the first force-generating means 3.6 is moved downwards, the piston 3.7.2 of the second force-generating means 3.7 is relieved from the pressure in the bottom dead center UT and the active connection of the holder 3.3.1 (FIG. 2) with the intermediate level 3.4 is released after the bottom end position U of the holder 3.3.1 (FIG. 2) and c) in the return sequence to the initial position, in accordance with Phase III, the tie rod 2.1.2 is freely moved in the locking unit 3.4.1, so that the intermediate level 3.4 is held in the bottom position U (FIG. 1) by the pressure from the upper chamber 3.6.1.1 of the cylinder 3.6.1 of the first force-generating means 3.6 and then moved to the initial position A.

(31) An alternative solution is also explainable based on FIG. 3 according to which the carrier unit of the drawing device 3.3 (e.g., FIG. 2) such as the intermediate level 3.4 can be moved to the upper initial position by means of an external force induced by a spring or a pneumatic cylinder, analog to the action of the first force-generating means 3.6 and the active connection can be implemented immediately before reaching the first position by means of a coupling element analogue to the locking unit 3.4.1.

(32) A second construction variant of the press according to the invention with a translatorily coupled active connection is shown in FIG. 4. In contrast to the first construction variant, an auxiliary tie rod 2.2 attached to respectively one coupling connecting rod 2.1.3.1 of the rotatory coupling 2.3 with the connecting rod 2.1.3 and the tie rod 2.1.2 here assumes the features which function similarly to the intermediate level 3.4 and the locking unit 3.4.1. Hereby, only the first force-generating means 3.6 is required as a consequence of the implementation and action of the rotatory coupling 2.3.

(33) A third construction variant of the press 1 according to the invention with a translational coupling is shown in FIG. 5 which is similar to the first construction variant but where only the first force-generating means 3.6 is necessary, wherein the function of the second force-generating means 3.7 apparent in FIG. 3 is carried out by the pressurization of the piston 3.4.2 in the locking unit acting in the same way as in FIG. 3.

(34) In general, the method is advantageously implemented in such a manner that the carrier unit is pre-accelerated by a value reduced by the value of the speed of the plunger 1.1, said value amounting preferably to 80% of the speed of the plunger 1.1.

(35) A counterforce required for the forming process is applied onto a floor of the carrier unit, such as an intermediate level 3.4 and/or a pressure cheek 3.5, by means of the energy-saving force flow K apparent in FIG. 2.1, said force flow K being created and closed without power loss by the first force-generating means 3.6 through its direct interaction with the components of the carrier unit, the tie rods 2.1.2, the plunger 1.1, the upper tool part 1.2, the work piece 5 and the holder 3.3.

(36) In order to remove the work piece 5 from the bottom tool part 3.2, the holder 3.3.1 is lifted by the first force-generating means 3.6 or second force-generating means 3.7 or by temporary closure of the positive, frictional and/or force-fit active connection.

(37) With the control and regulation device 4 integrated in FIG. 2 for recording, evaluating and controlling/aligning, values or parameters for at least one of the dimensions or gradients of forming forces, counterforces or of a speed to be transmitted or of one of the positions of the work steps of forming, of the elements of the drive device 2.1, of the positions of the plunger 1.1, of the holder 3.3, or of the carrier unit,

(38) are evaluated for the change from the closed to the released active connection or vice versa.

(39) A so-called hybrid version of the press 1 according to invention with a rotatory and translational coupling using a coupling connecting rod 2.1.3.1 is shown in FIG. 7, in which a telescopic extension mechanism is provided in the coupling connecting rod 2.1.3.1 hinged to the connecting rod 2.1.3. The eccentric rotatory drive transmitted by the drive device 2 (as shown also in FIG. 2, FIG. 2.1, FIG. 4, FIG. 5, FIG. 6.1, FIG. 6.2) via the connecting rods 2.1.3 to the tie rods 2.1.2 is transformed into an expedient translational active connection with the components of the drawing device 3.1 by the action of the telescopic extension mechanism of a double acting cylinder in the connecting rod 2.1.3.1. As defined by the inventive concept, the active connection can also be operated in a coupled and/or decoupled manner in the change of the respective stroke H. In this hybrid version, the coupling connecting rod 2.1.3.1 is schematically shown to the left of the center line in terms of a frictional-translational active connection and to the right of the center line in terms of a hydraulic-force-fit translational active connection.

(40) Another hybrid variant of a rotatory and translational coupling using a coupling connecting rod 2.1.3.1 is symbolically shown in FIG. 7.1. In the same way as in FIG. 6.1 and FIG. 6.2, the eccentric coupling element 2.3.2.1 is in turn integrated here into the (quasi-second) wheel 2.3.2 so as to be movable relative to it, in order to be able to operate the active connection in the change of the respective stroke H in a coupled and/or uncoupled manner.

(41) The press 1 is implemented with a parallel and linear guide 3.5.1 schematically shown in FIG. 6.1, FIG. 6.2, FIG. 7 and FIG. 7.1 for the carrier unit with intermediate level 3.4 or pressure cheek 3.5 or intermediate level 3.4 and pressure cheek or only with pressure cheek in the free space 3.3.2 of the bottom section 3.

(42) In general, the rotatory coupling 2.3 of the drive trains 2.1 of the drive device 2 shown in FIG. 4 is accommodated in the free space 3.3.2 or outside of it, wherein, in this case a motor 2.1.1 not shown with a connecting control and regulation device 4 not shown can be used.

INDUSTRIAL APPLICABILITY

(43) In accordance with the object, a new method for operating a press with a bottom drive as well as a new press are created, wherein a functional, technologically usable areaon the one hand, in technological steps of drawing with a drawing device and energy-efficient drive kinematics and on the other hand in technological steps of the removal of cutting wasteis created in the bottom structure. Since the press becomes compactly implementable and economically operable as a large press and as a transfer press in transfer lines with energy-optimized performance data, the method and the press with its presented variants according to the invention can implement economic and energetic benefits more specifically for operators of generic presses as compared to previous presses.

LIST OF REFERENCE SIGNS

(44) 1=press 1.1=plunger 1.2=upper tool part 2=drive device 2.1=drive train 2.1.1=motor 2.1.2=tie rod 2.1.2.1=tie 2.1.2.2=shoulder 2.1.3=connecting rod 2.1.3.1=coupling connecting rod 2.2=auxiliary connecting rod 2.3=rotatory coupling 2.3.1=first wheel 2.3.2=second wheel 2.3.2.1=eccentric coupling element 3=bottom section 3.1=table 3.2=bottom tool part 3.3=drawing device 3.3.1=holder 3.3.2=free space 3.4=intermediate level 3.4.1=locking unit 3.4.2=piston 3.4.3=cylinder (housing) 3.4.3.1=first chamber 3.4.3.2=second chamber 3.4.4=locking element 3.5=pressure cheek 3.5.1=parallel and linear guide 3.6=first force-generating means 3.6.1=cylinder 3.6.1.1=upper chamber 3.6.1.2=bottom chamber 3.6.1.3=piston rod 3.6.1.4=piston crown 3.6.2=piston 3.7=second force-generating means 3.7.1=cylinder 3.7.2=piston 4=control and regulation device 5=work piece A=first position B=second position C=third position E=eccentricity H=stroke of the plunger 1.1 h=stroke of the holder 3.3.1 H.sub.Zyl=stroke of the cylinder 3.6.1 K=force flow OT=top dead center of the plunger 1.1 UT=bottom dead center of the plunger 1.1 O=upper initial position of the holder 3.3.1 U=bottom end position of the holder 3.3.1