Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D5/00—Bending sheet metal along straight lines, e.g. to form simple curves
  • B21D5/02—Bending sheet metal along straight lines, e.g. to form simple curves on press brakes without making use of clamping means
  • B21D5/0272—Deflection compensating means
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21D5/00—Bending sheet metal along straight lines, e.g. to form simple curves
  • B21D5/04—Bending sheet metal along straight lines, e.g. to form simple curves on brakes making use of clamping means on one side of the work
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
  • B65D27/00—Envelopes or like essentially-rectangular containers for postal or other purposes having no structural provision for thickness of contents
  • B65D27/06—Envelopes or like essentially-rectangular containers for postal or other purposes having no structural provision for thickness of contents with provisions for repeated re-use

Definitions

• the invention relates to a bending machine comprising a machine frame, an upper beam and a lower beam, both of which are held on the machine frame and are movable relative to one another, a bending beam held on the machine frame and movable relative to this and to the upper beam and lower beam with a bending beam carrier and one on the bending beam carrier via one bending beam tool supported by a control controllable crowning device.
• the crowning device is adjusted in a manual manner, the suitable setting of the crowning device for a specific bending operation being ascertained by a series of tests.
• the invention has for its object to improve a bending machine of the generic type in such a way that the setting of the crowning device is possible faster and more precisely.
• the crowning device is provided with an actuating device which can be operated during a bending operation, and that the control device can also control the actuating device during a bending operation, in that at least one sensor assigned to the control It is provided with which the control can determine an adjustment of the crowning device by the actuating device and that for a specific bending operation the control can determine at least one setting parameter for the crowning device, in which the bending beam tool is oriented essentially free of deflection when this bending operation is ended.
• the advantage of the solution according to the invention can be seen in the fact that in this there is the possibility, on the one hand, of setting the crowning device during a bending operation via the control and, on the other hand, the control has the possibility of determining at least one setting parameter for the crowning device for a specific bending operation, which one the bending beam tool is aligned essentially free of deflection when this bending operation is completed.
• the number of setting parameters can be different in the solution according to the invention.
• the at least one setting parameter is a single setting parameter, namely the maximum setting parameter that occurs during the specific bending operation.
• the at least one setting parameter is a single setting parameter, namely the maximum setting parameter that occurs during the specific bending operation.
• a more precise, in particular individual bending areas during the course of the bending operation adapted adjustment of the crowning device is possible if the crowning device can be adjusted according to a variety of setting parameters during the particular bending operation.
• control system sets the setting parameters that exactly correspond to the bending states that go through during the bending operation.
• control can be used to determine the at least one setting parameter for a specific bending operation during the execution of this bending operation.
• the determination of the at least one setting parameter by measurement is conceivable in a wide variety of ways.
• the setting parameters are determined on the part of the control system by the constant adjustment of the crowning device in such a way that the bending beam tool remains straight, and at the same time as these setting parameters are determined, the crowning device is set accordingly.
• control for determining the at least one setting parameter comprises the deflection of the bending beam carrier by means of at least one sensor in the context of a measurement.
• the determination of the deflection of the bending beam carrier has the advantage that no measurement in the area of the bending beam tool and in particular no measurement of the straight direction of the bending beam tool during the bending operation is necessary, so that this solution allows the at least one setting parameter to be recorded particularly cheaply during the bending operation.
• the at least one sensor detects the deflection of the bending beam carrier at a single point thereof.
• the detection of the deflection of the bending beam carrier would be possible, for example, via a strain gauge, which could be arranged on the expanding side of the bending beam carrier.
• the at least one sensor detects the deflection of the bending beam carrier with respect to a reference position, so that it is not necessary to determine the zero position, which is problematic with a strain gauge.
• a particularly simple solution provides that the reference position is predetermined by a reference element.
• reference element can be provided in a wide variety of ways.
• a favorable solution provides that the reference element is a reference carrier which extends parallel to the bending beam carrier.
• the at least one sensor detects a relative change in position of the bending beam carrier with respect to the reference carrier.
• the deflection of the beam beam can now be linked in various ways with the setting parameter to be determined.
• a solution which is particularly favorable due to the simplicity provides that the control determines the setting parameters for the crowning device on the basis of the deflection of the bending beam carrier and an adjustment behavior of the crowning device.
• control system detects the setting of the crowning device by means of at least one position sensor assigned to the crowning device.
• the position sensor is preferably arranged at the end of the crowning device.
• a position sensor is arranged at both ends of the crowning device in order to determine its setting particularly precisely.
• the crowning device With regard to the setting of the crowning device, no further details have been given in connection with the previous explanation of the individual exemplary embodiments.
• the crowning device it is conceivable for the crowning device to be adjustable by means of the control during a bending operation in accordance with the setting parameter, with either the setting parameter also being able to be determined during the bending operation or the setting parameter having already been determined before the bending operation was carried out.
• This solution has the advantage that the setting of the crowning device can be implemented at least approximately in such a way that the crowning device also approximately provides a straight-directed bending beam tool during the bending operation.
• the crowning device is set at the end of the bending operation in such a way that the bending beam tool is essentially straightened, since any inaccuracies caused by a temporary deflection of the bending beam tool may thus occur until the end of the bending operation can be compensated during the bending operation.
• control by actuating the adjusting device, adjusts the crowning device in accordance with the deflection of the bending beam carrier which occurs at individual times during the execution of the bending operation.
• the crowning device can be adjusted by means of the control during the acquisition of the setting parameter in accordance with the setting parameter, so that the detected setting parameter is converted directly into the setting of the crowning device.
• the setting parameter is determined by measuring the straight direction of the crowning device.
• the crowning device can be set to the at least one setting parameter before the specific bending operation is carried out.
• a solution is particularly favorable in which the crowning device can be set in any operating state in accordance with the setting parameter.
• control system for carrying out a specific bending operation determines the setting parameter for this specific bending operation while it is being carried out.
• the at least one setting parameter must always be determined again each time the specific bending operation is carried out.
• the control it is conceivable for the control to determine the at least one setting parameter at least approximately before carrying out another of the specific bending operations.
• the at least one setting parameter can be determined in the course of carrying out a specific bending operation, but this determined setting parameter is used not only for setting the crowning device in this specific bending operation, but also in other specific bending operations, for example in the case of the production of other identical parts with repeated execution of the specific bending operation can be used.
• the at least one setting parameter determined in the previous specific bending operation can be used, at least for faster setting of the crowning device, since the setting of the crowning device to this approximate value can be initiated from the approximate familiarity of the setting parameter and thus the measurement in such a case would only have to compensate for deviations from the approximate value and would have to compensate for it by additional control of the crowning device.
• control system determines the at least one setting parameter essentially precisely before carrying out another of the determined bending operations, since in this case when it is detected of the at least one setting parameter in the course of a bending operation, the same at least one setting parameter could be used in the further bending operations.
• the crowning device can be preset by means of the control before the specific bending operation is carried out.
• An advantage would be that by presetting at least a partial value of the at least one setting parameter, the response time of the crowning device for the setting is reduced and the setting parameter can thus be set faster and more precisely.
• the crowning device can be preset by means of the control to a value above a presumed setting parameter and then to the setting value during the Bending operation can be lowered.
• This presetting of the setting parameter beyond the presumed setting parameter, that is to say values above this, has the advantage that it is possible during the bending operation to use the bending forces acting on the crowning device in addition to the force generated by the adjusting device to add the crowning device shift, namely in the direction of lower values of the setting parameters, that is from higher crowning in the direction of lower crowning, so that smaller setting forces are required and the crowning device can be set faster.
• the crowning which is then too strong at the beginning of the bending operation is not disadvantageous, provided that it is ensured that the crowning corresponding to the deflection of the beam carrier is set at the end of the bending process.
• the at least one setting parameter once defined for a bending operation, continues to be used by the control as a setting parameter in a further one of the determined bending operations, since in this case the actual determination of the setting parameter, for example, by only one or a few of the determined bending operations Measure, takes place, and this one setting parameter can then be used in all further of the specific bending operations, and the time required for the measurement to determine the setting parameter can be saved.
• Figure 1 is a front view of a bending machine according to the invention with indicated crowning device
• FIG. 2 shows a section along line 2-2 in FIG. 1;
• FIG. 3 shows an enlarged illustration of a bending cheek of the bending machine according to the invention with partially broken open areas for recognizing the crowning device and a reference carrier;
• FIG. 4 shows an illustration similar to FIG. 3 with the crowning device being essentially recognizable
• Figure 5 is an enlarged view of a region A in Figure 4.
• FIG. 6 in FIG. 6a shows a deflection of a bending beam carrier in a bending machine according to the invention in the course of a bending operation up to a maximum bending angle;
• An embodiment of a bending machine according to the invention shown in FIG. 1, comprises a machine frame 10 with side stands 12 and 14, between which, as shown in FIGS. 1 and 2, an upper beam 16 and a lower beam 18 extend.
• the lower beam 18 is fixed on the stands 12 and 14 and the upper beam 16 is movable relative to the lower beam 18.
• the upper cheek carries an upper cheek tool 20 and the lower cheek a lower cheek tool 22, between which a workpiece 24 made of flat material, for example a sheet metal, can be clamped in such a way that a tab 26 protruding beyond the upper cheek tool 20 and the lower cheek tool 22 consists of a through the lower cheek tool 22 and the upper beam tool 20 fixed clamping plane 28 is bendable.
• a workpiece 24 made of flat material, for example a sheet metal
• the bending machine is provided with a bending beam 30 which extends between the bending beam holders 32 arranged at the ends thereof and can be pivoted about a pivot axis 34 with these bending beam holders 32, the pivot axis 34 preferably being above the clamping plane 28 and parallel to it.
• the bending beam 30 acts on the flap 26 of the workpiece 24 with a bending beam tool 36, the bending beam tool 36 being supported on a bending beam carrier 42 of the bending beam 30 via a crowning device 40, and the bending beam carrier 42 is provided for this purpose, which acts on the bending beam tool 36 To absorb forces and thereby keep the bending beam tool 36 dimensionally stable.
• the bending beam tool 36 would be kept dimensionally stable such that its bending edge 44 extends exactly parallel to the pivot axis 34, regardless of the reaction forces acting on the bending beam tool 36 when the workpiece 24 is bent.
• the bending beam 30 extends between the lateral uprights 12, 14 over great lengths, depending on the type of workpiece 24 to be bent - in particular material, workpiece thickness and workpiece length -, the position of the workpiece 24 to be bent and the angle to be bent, a more or less strong deflection of the bending beam carrier 42 and thus a corresponding bending of the bending beam tool 36, unless this is counteracted by the crowning device 40.
• the crowning device 40 by means of which the bending beam tool 36 is supported on the bending beam carrier 42, is designed in such a way that, as is apparent from FIGS.
• the crowning device 40 with successively arranged wedge pairs 46 ! to 46 n , which each comprise a lower wedge body 48a, which is firmly seated on the bending beam support 42, and an upper wedge body 48b which is seated thereon and which, with its wedge surfaces 50a and 50b facing each other, slide against one another. Furthermore, it varies with different wedge pairs 46 ! up to 46 N the wedge angle of the wedge surfaces 50a, b in such a way that the wedge angle for the outer wedge pairs 46 ⁇ and 46 n is the smallest and steadily increases towards a center line 52, so that 46 x the one or more central wedge pairs Inclination of the wedge surfaces 50a, b is greatest.
• the upper wedge bodies 48b ⁇ bis 48 ⁇ in a longitudinal direction 54 of the crowning device 40 which at the same time also corresponds to a longitudinal direction of the bending beam 30, with respect to the lower wedge bodies 48a ⁇ to 48a n and a bending beam tool holder arranged between the bending beam tool 36 and the upper wedge bodies 48b ⁇ to 48b n 56 displaceable, in each case successive upper wedge bodies 48b abutting one another in the longitudinal direction 54, so that all upper wedge bodies 48b can be displaced in the longitudinal direction 54 simultaneously and by the same path.
• pairs of wedges 40 a stronger deflection of the bending beam tool 36 in the direction of the bending beam carrier 42 b 46 ⁇ to 46 ⁇ causes a shift of the upper wedge body 48b near the center line 52 of the curving away than in the region of the outer wedge pairs 46 ⁇ and 46 n , as shown in Fig. 4.
• Such an adjustability of the crowning device 40 makes it possible to compensate differently strong deflections of the bending beam carrier 42 in the direction away from the pivot axis 34 in a corresponding manner by the crowning device 40, so that can approximately adjust the bending edge 44 so that it extends approximately parallel to the pivot axis 34 and thus also to the bending line.
• an actuating device designated as a whole by 60, which comprises the respective end wedge pairs 46 ⁇ and 46 n associated hydraulic cylinders 62 and 64, which act on the respective upper wedge bodies 48b ⁇ and 48b n via pressure bodies 66 and 68, respectively one of the hydraulic cylinders 62 or 64 is effective.
• the hydraulic cylinder 62 is effective; if the upper wedge bodies 48b are to be displaced in the direction of the hydraulic cylinder 62, the hydraulic cylinder 64 is effective.
• the actuating device 60 is also provided with a hydraulic control 70, via which the hydraulic cylinders 62 and 64 can be acted upon in a controlled manner with hydraulic medium.
• the hydraulic control 70 corresponds to a control 72 for the bending machine.
• the controller 72 is able to detect the deflection of the bending beam carrier 42.
• the bending beam carrier 42 is preferably designed as a hollow body, so that a reference carrier 80 can be arranged in the bending beam carrier 42, which likewise extends in the longitudinal direction 54 of the bending beam carrier 42 essentially over its length and in the region of its two ends 82 and 84 on the bending beam carrier 42 is held near the end regions 86, 88 connected to the bending beam holders 32.
• the reference carrier 80 runs within the bending beam carrier 42 in such a way that it is not subjected to any loads and therefore cannot bend with the bending beam carrier 42 when it is loaded during a bending operation.
• the reference carrier 80 thus represents a geometric reference against which the deflection of the bending beam carrier 42 can be determined.
• a first sensor 90 connected to the bending beam carrier 42 is provided, which is connected to the bending beam carrier 42, for example, via a holding bracket 92.
• the first sensor 90 detects a distance between this and a lower edge 94 of the reference carrier 80, this distance increasing Deflection of the bending beam carrier 42 becomes increasingly larger, so that the distance from the lower edge 94 detected by the first sensor 90 corresponds to the maximum bending of the bending beam carrier 42.
• the first sensor 90 connected to the control 72 thus provides a measure of the maximum deflection of the bending beam support 42 when bending forces act on the bending beam tool 36.
• the control 72 is able to determine setting parameters E for the crowning device 40 and to control the hydraulic control 70 accordingly, so that the suitable hydraulic cylinder 62 or 64 is acted upon by hydraulic medium.
• the outermost upper wedge bodies 48b ⁇ and 48b n are assigned second sensors 100, each of which has a relative position of the outermost upper wedge bodies 48b ⁇ and 48b n determine to a fixed point 102, which is arranged in a fixed position relative to the bending beam support 42, preferably an end region 86 or 88 thereof.
• the control 72 By means of the second sensors 100 there is thus the possibility for the control 72 to recognize whether the adjusting device 60 has adjusted the crowning device 40 in accordance with the predetermined setting parameter E.
• the assignment of the setting parameter E required in each case for the setting of the crowning device 40 to the corresponding deflection D of the bending beam carrier 42 can be determined in the course of a calibration process in which the straight direction of the bending beam tool 36 is reached with different loads and in the control 72 in In the form of a table.
• the controller is able to determine corresponding setting parameters E for the crowning device 40 in the event of different deflections D of the bending beam carrier 42, in which the crowning device 40 acts on the bending beam tool 36 in such a way that the latter is essentially rectilinear and parallel with the bending edge 44 to the pivot axis 34 and thus parallel to the bending line.
• the crowning device 40 can be set in different operating modes, as shown in FIG. 6.
• FIG. 6a shows the deflection D of the bending beam carrier 42 as a function of a bending angle W, that is to say a pivot angle about the pivot axis 34.
• the deflection D when bending up to an angle of, for example, 90 °, the deflection D initially increases approximately linearly with the bending angle W in a first bending angle range Bl and then, for example, at a bending angle W of approximately 4 °, changes into a second bending range B2, in which with increasing bending angle W there is only a slight, approximately linear increase in the deflection D of the bending beam support 42 with increasing bending angle W.
• the transition from the bending area B1 to the bending area B2 is related to the fact that when the flow limit of the material of the workpiece 24 is exceeded, the forces acting on the bending beam tool 36 only increase slightly with increasing bending angle W.
• the controller 72 can now specify different setting parameters in accordance with the course of the deflection D over the bending angle W.
• the setting parameter E can be set by the control 72 exactly following the course of the deflection D, provided the actuating device 60 works at a sufficiently high speed in order to pass the bending angle quickly W to achieve a correspondingly quick readjustment of the crowning device 40.
• the setting parameter E is set with a certain delay, or a certain following error, as is shown by curve 1 in FIG. 6b, so that the Setting parameters E only reach the values corresponding to the deflection D in the bending range B2 from a bending angle W of approximately 5 °, but then the setting parameters E follow the deflection D until the maximum bending angle W is reached.
• Such a tracking error has no serious disadvantageous effects for the precision of the bending process, provided that the deflection D of the Bending beam carrier 42 corresponding setting parameters E can be reached by the end of the bending operation, because nevertheless the bending beam tool 36 is corrected in terms of its deflection when the bending operation is ended, and thus the bent flap 26 is bent at the end of the bending operation in such a way as if the setting parameter E coexisted exactly the deflection D of the bending beam support 42 would have been set.
• the setting parameter E in the first operating mode corresponding to curve 0 or in the second operating mode of curve 1 in FIG. 6b is usually given when the particular bending operation was carried out by the bending machine for the first time, since in such a case the control 72 usually does not have any There are indicative values for the resulting deflection D of the bending beam support 42.
• bending operations are not only carried out once, but rather the same specific bending operation is carried out several times in succession on a new workpiece 24.
• control 72 already has maximum values for the setting parameter E in this bending operation due to the previous bending operations.
• a third operating mode - as shown by curve 2 in FIG. 6b - the controller 72 can start before the bending operation Already pre-set the crowning device 40 with a setting parameter E which is below the maximum value.
• This setting parameter E is maintained as a constant value until, due to the deflection D of the bending beam support 42, this setting parameter E is reached and subsequently adapted when the deflection D is further increased, a drag error also occurring in this regard, but this quickly occurs in the bending range B2 reduced, so that towards the end of the bending operation, the setting parameter E corresponds to the bending of the bending beam carrier 42 which is set.
• actuating device 60 is required that the crowning device 40 is preset by an adjustment parameter E such that the crowning is greater than the necessary crowning. Beginning with the bending operation, the crowning of the crowning device 40 is then withdrawn, up to a value corresponding to the deflection D of the bending beam support 42 and possibly still slightly adjusted in the bending area B2.
• the determination of the deflection D of the bending beam carrier 42 can also be completely dispensed with in subsequent bending operations and the final value of the setting parameter E determined in a first bending operation is fixed in the subsequent bending operations can be set, as can be seen in a fifth operating mode, represented by curve 4 in FIG. 6b.

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• 2002
  • 2002-09-26 DE DE10245777A patent/DE10245777A1/de not_active Withdrawn
• 2003
  • 2003-06-26 WO PCT/EP2003/006731 patent/WO2004033125A1/fr active IP Right Grant
  • 2003-06-26 JP JP2004542257A patent/JP2006500224A/ja active Pending
  • 2003-06-26 EP EP03740348A patent/EP1542816B8/fr not_active Expired - Lifetime
  • 2003-06-26 PT PT03740348T patent/PT1542816E/pt unknown
  • 2003-06-26 DE DE50309893T patent/DE50309893D1/de not_active Expired - Lifetime
  • 2003-06-26 AT AT03740348T patent/ATE395991T1/de active
  • 2003-06-26 DK DK03740348T patent/DK1542816T3/da active
  • 2003-06-26 ES ES03740348T patent/ES2305478T3/es not_active Expired - Lifetime
• 2005
  • 2005-03-24 US US11/088,442 patent/US7234332B2/en not_active Expired - Lifetime

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