System of a Frame for Presses

Abstract

A system of a separable frame for presses and press frames (1), the respective press frame (1) comprising uprights (2) and a head piece as an upper cross connection (3) and a press table as a lower cross connection (4), which as structural units form a closed frame that absorbs static and dynamic forces for any required functions of a press such as the drive of a ram used for forming with tools. The uprights (2) are attachable laterally or longitudinally to the cross connections (3, 4) by non-positive or non-positive and positive joining geometries (5) and releasable connector (5.1). The proposed press frames (1) have a reduced vertical deflection (v2) compared to press frames joined by tie rod bracing (6).

Claims

1-32. (canceled)

33. A system of a frame for presses, comprising as a press frame (1) having structural units constructed as at least two uprights (2), as an upper cross connection with a head piece (3) and as a lower cross connection (4) with a press table (4) and forms a closed and releasably joined frame that receives static and dynamic forces of the presses, wherein a) the at least two uprights (2) having a length (L) are manufactured as a structural unit and joined in abutment laterally or longitudinally to the cross-connections (3, 4) by way of non-positive or non-positive and positive joining geometries (5) and releasable connectors (5.1) without tie rods, b) the at least two uprights (2) are subjected to tensile stress under an operating force (Fp) of the presses, and c) at least one of the two uprights (2) has a structure designed different from that of the other uprights such that it deforms symmetrically under the operating force introduced asymmetrically into the uprights (2), and has cross-sectional regions differentiated commensurate with acting press forces such that at least one cross section of the upright (2) is constructed in sections in an open or closed and/or asymmetrical shape.

34. The system of a frame for presses according to claim 33, wherein in accordance with the relationship v2≤1/n*v1, and wherein n=(s+k)/(s+1), and v1=a vertical deflection of a tensioned system under the action of Fp1, v2=the vertical deflection of the system under the action of Fp2, n=an advantage factor, s=a stiffness ratio, and k=a cost factor.

35. The system of the frame for presses according to claim 33, wherein the uprights (2) are structurally designed to counteract a different type of bending tendency originating from the upper cross connection (3) or the lower cross connection (4).

36. The system of the frame for presses according to claim 33, wherein the non-positive and positive joining geometries (5), joiners (5.2) and the releasable connectors (5.1) connecting the uprights (2) and the cross connections (3, 4) are designed commensurate with the acting pressing forces and include an overload protection.

37. The system of a frame for presses according to claim 33, wherein the frame receiving the cross connections (3, 4) with the uprights (2) and the joining geometries (5) connected to form the press frame (1) and subjected to shape changes and all the stresses and changes in shape of the operation of a press without tie rod bracing has at least one structural unit or transport unit for receiving functional structural units (7) of the press in the transport or operating state.

38. The system of a frame for presses according to claim 33, wherein at least one upright (2) is permanently dimensioned or designed asymmetrical in relation to the other upright (2), while a) taking into account off-center operating forces of the presses and avoiding component damage, b) counteracting disadvantageous elastic changes in shape or changes in play in a ram guide, or c) optimizing multi-ram presses.

39. The system of a frame for presses according to claim 33, wherein at least one of the uprights (2) is constructed such that an axle bolt is placed in the associated head piece (3) in the region of the upright (2) having a suitable open cross-section or similar mounting opening for reducing the length of the head piece (3) or the press.

40. A press frame (1) including the system of claim 33, wherein, for overload protection of the press frame (1), overload protector designed as predetermined break connections including at least one of shear bolts, elastic positive connections or non-positive cylindrical connections, and hydraulic or preloaded mechanical springs which yield when a maximum pressing force (Fp) is exceeded, are arranged in the uprights (2) or between the uprights (2) and the cross-connections (3, 4).

41. The press frame (1) according to claim 33, wherein the non-positive or non-positive and positive joining geometries (5) or releasable connectors (5.1) are formed as predetermined break elements, elastic connections, hydraulically preloaded spring elements, mechanically preloaded spring elements or frictional elements.

42. The press frame (1) according to claim 33, wherein at least one design counteracts the deflection of the cross connections (3, 4) by way of one of broad-crowned feather keys, or dovetail connections, also with a one-sided bevel, or single- or multi-part wedges and feather keys.

43. The press frame (1) according to claim 33, wherein the connectors (5.1) automatically adjust its preloading force to compensate for run-in and settlement phenomena in the connection by joining geometry (5), by way of at least one of spring-actuated conical clamping system, or hydraulic clamping system, or spring-loaded single or multi-part wedge system, or weight-tensioned system.

44. The press frame (1) according to claim 33, wherein having structurally differently designed uprights (2) at an inlet side and an outlet side of the press or press stage to counteract different stage forces, even having phase-offsets, and to reduce the tendency of overall deformation of the press frame (1) under the operating force.

45. The press frame (1) according to claim 33, wherein having a design without a tool-internal guide due to reduced ram guide play, including in an effective range of a maximum operating force.

46. The press frame (1) according to claim 33, further comprising traverses connecting adjacent uprights (2) to increase the overall stiffness of the press frame (1).

47. (canceled)

48. The press (1) according to claim 33, further comprising a cross and longitudinal traverse implemented as a functional structural unit (7) comprising one of a drive unit for automation, or a fluid unit including installation, or a sensory part/workpiece monitoring, or a light barrier, or a lighting system.

49. The press frame (1) according to claim 33, wherein the upper and lower cross connections (3,4) of the uprights (2) are braced by at least one clamping element activatable for variable adjustment of the stiffness of the press frame (1).

50. The press frame (1) according to claim 33, wherein the releasably joined frame comprises the uprights (2) having a mutually different height (L) and/or the upper and lower cross connections (3,4) having a mutually different width (b).

51. The press frame (1) according to claim 33, wherein a transport dimension (b) of a temporary transport unit comprising structural units of the upper or lower cross connections (3, 4) is smaller compared to a final structural unit dimension (B) of the press.

52. The press frame (1) according to claim 33, wherein a receptacle formed in at least one of the uprights (2) for at least one of the functional structural units (7) of the presses drive unit of an automation system together with accessories, traverse for lighting and optical surveillance, oil tank, air tank, tool lubrication/drawing agent, hydraulic lines, cooling line and power cable for servo drive, control/regulation/switch box, control panels, other operating elements, service box for manual auxiliary devices, cleaning devices, flashlights, tools, compressed air, accessories for other sensors, vibration damping elements as a temporary transport unit or for a press operation.

53. A computer program for the system of the press frame (1) according to claim 33 for structural design of a) the uprights (2) to be produced with a length (L) and attached to the cross connections (3, 4) laterally or longitudinally by way of the non-positive or non-positive and positive joining geometries (5) and the releasable connector (5.1) without tie rod bracing (6), or b) the upright (2) to be subjected to tension under an operating force (Fp) of the presses, or c) the press frame (1) to be designed with a reduced vertical deflection (v2), wherein the integration of a program step for determining the reduced vertical deflection v 2 according to the relationship v2≤1/n*v1, wherein n=(s+k)/(s+1) and v1=a vertical deflection of a tensioned system under the action of Fp1, v2=the vertical deflection of the system under the action of Fp2, n=an advantage factor, s=a stiffness ratio, and k=a cost factor.

54. A control and regulating device for the system of the press frame (1) according to claim 33, which comprises as the press frame (1) structural units with uprights (2), an upper cross connection with a head piece (3) and a lower cross connection (4) with a press table (4), and a closed and releasably joined frame absorbing static and dynamic forces of the presses, wherein a) at least one measuring device, such as a strain gauge, corresponding in the system for receiving data relating to static and dynamic forces of the press of the loads in the structural units comprising the press frame (1), the uprights (2), the upper cross connection (3) and the lower cross connection (4), b) evaluation of this data in a computer; and c) outputting data pertaining to static and dynamic forces of the press for control/regulating measures for elastic behavior of the structural units of the press frame (1); wherein a load-dependent controlled/regulated variable adjustment of the stiffness of the press frame (1) for an active bracing of stiffness-relevant cross sections of the uprights (2) by way of activatable clamping elements.

55. The press frame (1) according to claim 49, further comprising clamping elements operatively as overload protection or counterbalancing ram weight.

56. System of a frame for presses according to claim 33, wherein the uprights (2) are structurally designed so as to deform mutually symmetrically under an operating force introduced asymmetrically in the uprights (2) when using of dual uprights in multi-ram presses, namely when loaded differently by different pressing forces of the respective rams.

57. Press frame (1) according to claim 33, comprising an extension of the uprights (2) downwards instead of concrete foundation supports.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0090] FIG. 1a shows a force/deformation diagram (tension diagram) illustrating the elastic changes in shape and dynamic loads of connected tie rods and uprights,

[0091] FIG. 1b shows a force/deformation diagram illustrating the elastic change in the shape and thus the dynamic load in the upright without tie rods,

[0092] FIG. 2 shows the structural principle of the press frame according to the invention corresponding to FIG. 1b) without tie rods, illustrating a smaller transport dimension b compared to a conventional design shown in FIG. 3,

[0093] FIG. 3 shows a press frame according to the prior art,

[0094] FIG. 4 shows details relating to joining geometries/surfaces and releasable connecting means as well as insertion of functional structural units,

[0095] FIG. 5 shows a deformation scheme (hourglass effect), and

[0096] FIG. 6 shows an embodiment of the press frame according to the invention with longitudinally attached uprights.

WAYS OF CARRYING OUT THE INVENTION

[0097] For clarification the inventive systems compared with the prior art analyzed above, FIG. 1a shows firstly a diagram of the elastic behavior of a conventionally tie-rod-braced press frame 1 according to FIG. 3, from which an unillustrated overall stiffness can be derived, which causes a vertical deflection v1. The diagram corresponds to a classic screw tension diagram and shows the operative connection of a pre-tensioned screw, referred to here as tie rod analogous to a tie rod 6 (FIG. 3) in the press frame 1. This is intended to illustrate to a person skilled in the art (using the example of the press force distribution on four uprights) the distribution of the dynamic load onto conventional tie rods 6 and uprights 2.

[0098] The designations in the diagram are as follows: [0099] F=force in N [0100] Fp1=pressing force [0101] v=deflection in mm (according to DIN 55189 as elastic vertical deflection velz=elastic displacement in z-direction) [0102] v1=vertical deflection of the tensioned system under the action of Fp1 [0103] vt=deflection tie rod due to preload [0104] vu=deflection upright due to preload [0105] s=stiffness ratio of column to tie rod

[0106] This is based on the stiffness ratio s of the upright 2 (upright) and the tie rods 6 (tie rod) of, for example, 1.5:1, which is customary in press technology. Thus, the tie rods 6 experience the dynamic load proportion and the uprights 2 experience the dynamic load proportion corresponding to this stiffness ratio s. With a conventional preload of, for example, 1.3×pressing force Fp1, the spring deflection v1 can be deduced.

[0107] The diagram illustrates the unfavorable conventional distribution of the dynamic load on conventional tie rods and uprights because the tie rod, which was previously made of higher quality material, absorbs a lower dynamic load than the upright. The 1.5:1 stiffness ratio s of upright 2 to tie rod 6 causes a dynamic load distribution of 1.5:1 and thus prevents an optimized load distribution for the uprights. To increase stiffness, the tie rods 6 are therefore constructed of a more expensive/higher-load-bearing material than the uprights 2.

[0108] The preload achieved with the tie rods 6 has the disadvantage that, with an unchanged pressing force Fp1 and with an unchanged specified deflection v1, only a so-called residual clamping force is increased. If a higher pressing force Fp1 is required, a correspondingly higher deflection v1 must be accepted, which, for example, adversely affects the forming process.

[0109] Depending on the design, cavities/through holes are provided in uprights and cross-connections, such as the head piece and press table, and adequately dimensioned contact surfaces for the anchor nuts are provided on the head piece and the press table. A reinforcement/enlargement of the diameter of the tie rods would likewise result in an enlargement of the upright and/or of the external dimensions of the system, which due to the material consumption disadvantageously increases the financial outlay to be invested.

[0110] This development trend is, on the other hand, contravened by the system according to the invention of a frame for presses according to FIG. 2, FIG. 5 or FIG. 6, which includes as a press frame 1 structural units with uprights 2, an upper cross-connection with a head piece 3 and a lower cross-connection 4 with a press table and forms a closed and releasably joined frame that absorbs static and dynamic forces of the presses, and which is designed in such a way that [0111] a) the uprights 2 with a length L are manufactured as a structural unit and are joined laterally or longitudinally to the cross-connections 3, 4 by way of non-positive or non-positive and positive joining geometries 5 and releasable connecting means 5.1 without tie rods, [0112] b) the uprights 2 are designed to be subjected to tension with an operating force Fp, and [0113] c) the press frame 1 has a reduced vertical deflection v2 compared to a press frame (1) joined by way of tie rod bracing 6.

[0114] This system is based on more complex detailed considerations, according to which a relation of a factor n=(s+k)/(s+1) was created, which is based on a [0115] a cost factor k=price per kilo of tie rod/price per kilo of upright (in practice k>2), and [0116] the stiffness ratio s=column stiffness/tie rod stiffness (in practice s=1.5).

[0117] From this combined consideration which merges economic and technical issues of these characteristic parameters “k” and “s” and with the same financial investment as for the conventional design, the diagram according to FIG. 1b illustrates [0118] the reduced vertical spring deflection v21/n*v1, where n=(s+k)/(s+1) applies, and [0119] in this case, the increased operating force of Fp2=n*Fp1,
according to the invention, wherein, for example, k=2 and s=1.5 allow 1.4 times the stiffness (or 1/1.4 times the deflection) or 1.4 times the operating force.

[0120] In the diagram denote (in comparison to FIG. 1 a): [0121] F=force in N [0122] Fp2=pressing force in the press frame according to the invention [0123] v=deflection in mm (according to DIN 55189 as elastic vertical deflection velz=elastic displacement in z-direction) [0124] v2=vertical deflection under the action of Fp2 [0125] s=stiffness ratio.

[0126] FIG. 1b illustrates in this way the dynamic load distribution on the uprights according to the inventive system without the use of tie-rods with an unexpected deflection v2, which forms the basis for realizing the new and advantageous constructive configurations in the press frame, enabling the absorption of the entire dynamic load caused by the press force Fp2 by the uprights 2.

[0127] FIG. 2 illustrates schematically the construction similar to FIG. 1b) of the inventive press frame 1 with the advantageous overall height L of the upright 2, an upper cross-connection such as head piece 3, a lower cross-connection such as press table 4, joining geometries 5, releasable connecting means 5.1 and joining means 5.2, as well as with an advantages exemplary smaller transport dimension b relevant to the invention relative to final structural unit dimension B.

[0128] Conversely, FIG. 3 shows schematically a conventional design with the height L of the upright 2, with the tie rods 6 that disadvantageously protrude from this height and brace the upright 2 as well as the upper cross-connection such as the head piece 3 and the lower cross-connection such as the press table 4, and with a disadvantageous transport dimension b that equals the final structural unit dimension B.

[0129] This system of a frame for presses is completed in the press frame 1 with the following features, either alone or in combination: [0130] a design of the uprights 2 counteracting different types of bending tendencies of the upper 3 and lower cross-connection 4; [0131] an asymmetrical design of the uprights 2 in such a way that they deform symmetrically with respect to each other under an asymmetrically introduced operating force, especially when using double uprights in multi-ram presses (compact suction presses, step presses), wherein the respective rams are loaded differently by different press forces; [0132] a targeted dimensioning of the cross-sections of the uprights 2 by adapting cross-sectional regions commensurate with the acting pressing forces; [0133] an embodiment creating stiffness relevant cross-sections in the uprights 2 by active bracing to obtain an additional cross section for increasing the stiffness equal to the inner or outer cross-section; [0134] a design of the uprights 2 and cross-connections 3, 4 by way of connecting non-positive and positive joining geometries 5, joining means 5.2 and releasable connection means 5.1 including an overload protection commensurate with the acting pressing forces; [0135] the frame receiving the cross-connections 3, 4 with the uprights 2 and the joining geometries 5 and connected to the press frame 1, which absorbs changes in shape and the entirety of the stresses and changes in shape of the operation of a press without tie rod bracing, which has at least one structural unit or transport unit for accommodating functional structural units 7 of the press in the transport or operating state; [0136] a permanent dimensioning or design of least one of the uprights 2, in particular asymmetrically to one of the other uprights 2, for [0137] a) taking into account off-center operating forces of the press and preventing component damage, [0138] b) counteracting disadvantageous elastic changes in shape or changes in the play of a ram guide, or [0139] c) optimizing multi-ram presses; [0140] a sectional implementation of at least one is typical cross section of the upright 2 in an open or closed and/or asymmetric form; [0141] an implementation of at least one of the uprights 2 so that parts of a drive, such as an axle bolt, in the corresponding head piece 3 can be arranged in the region of the upright 2 with a corresponding open cross-section or with a similar assembly opening to reduce the length of the head piece 2 or of the press; [0142] formation of least one overload protection means by the joint geometry 5 or the joining means 5.2, or the connecting means (5.1).

[0143] The particular design features or properties are realized or characterized in the press frame 1 by the following features, either individually or in combination: [0144] To protect the press frame 1 from overload and as predetermined break connections, overload protection means constructed, for example, as shear bolts, hydraulic elements or as pre-tensioned mechanical springs, elastic form-fitting connections or form-fitting cylindrical connections, which yield when a maximum pressing force Fp is exceeded, can be arranged in the uprights 2 or between the uprights 2 and the cross-connections 3, 4. [0145] The positive or non-positive joining geometries 5 or releasable connecting means 5.1 are designed as [0146] a) elements having predetermined breaks, [0147] b) elastic connections, [0148] c) hydraulically biased spring elements, [0149] d) mechanically biased spring elements, [0150] e) friction-type elements. [0151] The press frame 1 has an advantageous force flow that acts positively on the deformation and local stress conditions of the press and depends the position and shape of the joining geometries 5 and connecting means 5.1. [0152] The press frame 1 has a design that counteracts the deflection of the cross-connections 3, 4 by way of [0153] broad-crowned feather keys, or [0154] dovetail connections, also with a one-sided bevel, or [0155] single- or multi-part wedges and feather keys. [0156] The press frame 1 has connecting means 5.1 which automatically adjust its preloading force to compensate for run-in and settlement phenomena in the connection, such as joining geometry 5, by way of at least one [0157] spring-actuated conical clamping system, or [0158] hydraulic clamping system, or [0159] spring-loaded single or multi-part wedge system, or [0160] weight-tensioned system. [0161] The press frame 1 is formed with structurally differently designed uprights 2 at the inlet side and the outlet side of the press or the press stage so as to suitably counteract the different stage forces, even having phase-offsets, and to reduce the tendency of (asymmetric) overall deformation of the press frame 1 under an operating force. [0162] The press frame 1 lacks a tool-internal guide due to reduced ram guide play, especially in the effective range of the max. operating force. [0163] To prevent fretting corrosion, the press frame 1 has in the joining geometries 5 sliding elements used locally or over a large area for the targeted generation of relative movements between the uprights 2 and cross-connections 3. 4.

[0164] Furthermore, according to the invention, this press frame 1 can be designed with the following special features: [0165] Adjacent upright 2 are in each case provided with traverses (longitudinal, transverse and diagonal) to increase the overall stiffness of the press frame 1. [0166] At least one functional structural unit 7 can be implemented as a transverse and longitudinal traverse by way of [0167] a drive unit for automation, or [0168] a fluid unit including installation, or [0169] a sensory part/workpiece monitoring, or [0170] a light barrier, or [0171] a lighting system. [0172] In the releasable connecting means 5.1, the axially mounted axle bolts and components are securely mounted to prevent detachment. [0173] If desired, at least one hydraulic, electromotive, pneumatic, thermal or sensory activatable clamping element is operatively connected to functions or facilities, such as for overload protection or to ram counterbalancing.

[0174] Only with the inventive system can the press frame 1 advantageously be constructed as a releasably joined frame, due to the uprights 2 having mutually different heights L and/or by upper and lower cross-connections 3, 4 having mutually different widths b.

[0175] This makes it possible, provided that the uprights 2 with the length L laterally or longitudinally can be joined with the cross-connections 3, 4 by way of non-positive or non-positive and positive joining geometries 5 and releasable connecting means 5.1 in abutment without tie rod bracing, to employ for special cases and/or different press genres, types, and arrangements, for example in multi-ram presses, press lines, multi-stage presses, transfer presses, [0176] within a single frame, mutually different lengths of uprights 2 and upper and lower cross-connections 3, 4, and in the regions of the joining geometries mutually different lateral or longitudinal joining types, [0177] with parallel and sequentially arranged frames, from frame-to-frame different lengths of uprights 2 and upper and lower cross-connections 3, 4 and different lateral or longitudinal joining types, or [0178] with sequentially arranged frames, from frame-to-frame different lengths of uprights 2 and upper and lower cross-connections 3, 4 and different lateral or longitudinal joining types,
while retaining values of a stress state, force flow, and stiffness required according to the invention with reduced vertical deflection v2. In this way, any on-site conditions of a press operator can be met by adapting each press frame through various configurations of lateral or longitudinal joining types, different lengths or widths of the uprights or the upper and lower cross-connections.

[0179] The press frame 1 can advantageously be also designed [0180] with a smaller transport dimension b, compared to a final structural unit dimension B of the press, for a temporary transport unit that includes the modules upper or lower cross-connections 3, 4, or [0181] with a downward extension of the uprights 2 instead of foundation supports made of concrete, or [0182] with a receptacle formed in at least one upright 2 for at least one of the functional structural units of the presses, such as [0183] Drive unit of a so-called automation system together with accessories, [0184] Traverse for lighting and optical surveillance, [0185] Oil tank, air tank, tool lubrication/drawing agent, [0186] Hydraulic lines, cooling line and power cable for servo drive, [0187] Control/regulation/switch box, [0188] Control panels, other operating elements, [0189] Service box for manual auxiliary devices, cleaning devices, flashlights, tools, compressed air, [0190] Accessories for other sensors, [0191] Vibration damping elements
as a temporary transport unit or for a press operation.

[0192] The usable cavities created by virtue of the elimination of the tie rods, allow vibration-damping materials, such as granulate and sand, to be embedded in the uprights 2.

[0193] In addition, the elimination of the tie rods together with anchor bolts allows more constructive freedom in design/location of the mounting surfaces of the press table, so that a vibration-isolating installation (spring elements) can be optimally placed and dimensioned, due to the elimination of previously necessary costly and time-consuming tightening of the anchor nuts for final structural unit at the site of the operator using a clamping device, which must be transported back and forth.

[0194] At a comparable and required deflection v, this means that the upright 2 assumes a stiffness that corresponds at least to the overall stiffness of the tensioned system according to FIG. 1 a.

[0195] Thus, the load-bearing walls of the uprights 2 can be reinforced inwardly by using thicker metal sheets up to and including a design representing a solid stand.

[0196] The typical cross section of the uprights 2 may be designed to have a partially open or closed, symmetrical or asymmetrical shape so as to specifically affect the deformation of the upright 2 or accommodate the function modules 7 in a space-optimized manner.

[0197] The play of the ram guide on the press is specifically influenced by designing the stiffness of certain sections in the uprights 2 such that advantageously a small play can be set during or shortly before the forming process.

[0198] When a non-uniform/asymmetrical distribution of the pressing force is required due to the use of special multi-stage tools or with multi-ram presses, the uprights 2 may thereafter be differently dimensioned corresponding to the load distribution.

[0199] Empty cavities in the uprights 2 can be used for other purposes, in order to implement in accordance with FIG. 4 function modules 7, such as for example, additional units, control elements, memory in a space-saving manner or vibration-damping materials.

[0200] Functional structural units 7 of the press automation can be integrated between two uprights 2 as a supporting/stiffening part of the press frame 1. At the same time, a three-part unit as a preassembled structural unit would make assembly work easier for the operator.

[0201] The time and money required to assemble and transport a press plant could be reduced; costly hydraulic auxiliary devices for the previously required clamping by way of tie rods 6 and anchor nuts are eliminated.

[0202] The reduced spatial requirements for production halls and operator buildings lead to significant cost reductions.

[0203] According to the invention, to refine the design, a program step for the determination of the reduced vertical deflection v2 according to the relationship v21/n*v1 can be integrated in a computer program for constructing [0204] a) the uprights 2 to be produced with a length L and attached to the cross-connections 3, 4 laterally or longitudinally by way of non-positive or non-positive and positive joining geometries 5 and releasable connecting means 5.1 without tie rod bracing 6, or [0205] b) the upright 2 to be subjected to tension under an operating force Fp of the presses, or [0206] c) the press frame 1 to be designed with a reduced vertical deflection v2,
wherein n=(s+k)/(s+1) and [0207] v1=a vertical deflection of a tensioned system under the action of Fp1, [0208] v2=the vertical deflection of the system according to the invention under the action of Fp2, [0209] n=an advantage factor, [0210] s=a stiffness ratio, and [0211] k=a cost factor.

[0212] A control and regulating device for the system according to the invention of a frame for presses includes [0213] a) at least one corresponding measuring means, preferably strain gauges, in the system for receiving data pertaining to static and dynamic forces of the press concerning the loads in units that include the upright 2, upper cross-connection and lower cross-connection 3, 4, [0214] b) Evaluation of these data in a computer, and [0215] c) Outputting data pertaining to static and dynamic forces of the press for control/regulating measures for the elastic behavior of structural units of the press frame 1,
so as to enable a load-dependent controlled/regulated variable adaptation of the stiffness of the press frame 1 for the active bracing of stiffness-relevant cross-sections of the uprights 2 by means of the above-mentioned activatable bracing elements.

INDUSTRIAL APPLICABILITY

[0216] The scope of the invention includes the targeted use of less expensive materials that can be processed very easily in terms of welding technology and are available worldwide.

[0217] The maximum weight and dimensions of the individual components produced according to the invention up to an entire press system in a press plant can be reduced.

[0218] The system according to the invention with the targeted change in the stiffness of the press frames by eliminating the vertical preloading makes the application of the presses more flexible or expands of their field of application.

[0219] The change in the stiffness of the uprights by activating, deactivating or changing additional tensionable cross-sections of the uprights allows the press frame to be optimally adapted to [0220] the tool to be used, e.g. increased upright stiffness for cutting tools, [0221] a reduced, minimum required stiffness for forming tools in order to achieve longer service lives of guides and other wear parts.

[0222] The selective use of material in determinable cross-sectional areas of the uprights to increase their stiffness increases the use-value for the press operator, both when the processing of high strength parts and also with respect to the critical cutting stroke when using cutting tools.

[0223] Elimination or reduction of the guide rods in the tool results in a structural simplification of the employed tools, which enables a more favorable workpiece transport and reduces tool costs.

LIST OF REFERENCE SYMBOLS

[0224] 1 press frame [0225] 2 uprights with height (=length) L [0226] 3 upper cross-connection, head piece [0227] 4 lower cross-connection, press table [0228] 4.1 joining geometry [0229] 4.2 detachable fasteners [0230] 4.3 joining agents [0231] 6 tie rods [0232] 7 functional structural unit [0233] b width, transport dimensions [0234] B final structural unit dimension, external dimension [0235] L height of the upright (=length of the unit) [0236] F force in N [0237] Fp1 pressing force [0238] Fp2 pressing force [0239] v deflection in mm [0240] v1 vertical deflection of the tensioned system under the action of Fp1 [0241] v2 vertical deflection of the system according to the invention under the action of

[0242] Fp2 [0243] vt deflection tie rod due to preload [0244] vu deflection upright due to preload [0245] s stiffness ratio of upright to tie rod [0246] n advantage factor [0247] k cost factor