Rear stop device for a bending machine

Abstract

The invention relates to a rear stop unit (7) with a stop and/or gripping and/or measuring element (10) for positioning a sheet (3) to be machined on a bending press. The stop and/or gripping and/or measuring element (10) is arranged on an adjustable bearing arm (13) by means of a pivot joint (12). The bearing arm (13) is connected to a guide rail (20) by means of an additional pivot joint (18) via a guide element (19). The rear stop unit (7) further comprises a support arm (21) which is connected to the bearing arm (13) via a joint (22) and to an additional guide element (24) via a rigid connection, and the support arm is connected to the guide rail (20) via the additional guide element. Furthermore, the joint (22) is designed as a rotational/prismatic joint. The position of the bearing arm (13) can thereby be adjusted by moving the support arm (21) in a linear manner along a guide direction (11) specified by the guide rail (20).

Claims

1. A rear stop device comprising a stop element for positioning a metal sheet to be processed on a bending press, wherein the stop element is arranged via a pivot joint on an adjustable bearing arm, which adjustable bearing arm is connected via an additional pivot joint to a guiding element, and by said guiding element to a guide rail, wherein a support arm, is connected by a joint to the adjustable bearing arm, and wherein the support arm is rigidly connected to an additional guiding element, and is mounted by said additional guiding element displaceably on the guide rail, and the joint is designed as a rotary slider joint.

2. The rear stop device as claimed in claim 1, wherein the pivot joint is designed as a rotary drive, and wherein a first angle between the stop element and an X axis perpendicular to a working plane of the bending press can be variably adjusted in the rotary drive.

3. The rear stop device as claimed in claim 2, wherein in the pivot joint a parallel kinematic is formed engaging with the stop element so that the first angle is always the same regardless of the position of the bearing arm.

4. The rear stop device as claimed in claim 1, wherein the stop element is mounted by a quick release device on the pivot joint and/or comprise at least one stop finger.

5. The rear stop device as claimed in claim 4, wherein a measuring unit detects a rotary moment introduced by a force exerted at a distance from a rotary axis, of the pivot joint, and perpendicular to a stop surface of the stop finger.

6. The rear stop device as claimed in claim 4, wherein the top finger comprises a plurality of stop surfaces, and wherein a control device is configured to control a position and location of the plurality of stop surfaces.

7. The rear stop device as claimed in claim 4, wherein the stop finger has a step-like shoulder comprising two stop surfaces formed at right angles to one another.

8. The rear stop device as claimed in claim 1, wherein the guide rail has separate guiding surfaces for mounting the guiding element and the additional guiding element.

9. The rear stop device as claimed in claim 1, wherein the additional guiding element and the guiding element can be displaced on the guide rail in a guiding direction independently of one another via two mechanical adjusting drives.

10. The rear stop device as claimed in claim 1, wherein the guiding element or the additional guiding element can be displaced in a guiding direction via a mechanical main adjusting drive such that the guiding element or the additional guiding element becomes a main guiding element, and wherein the other of the guiding element and the additional guiding element is coupled to the main guiding element by an additional mechanical adjusting drive to be movable relative to the main guiding element.

11. The rear stop device as claimed in claim 1, wherein a guiding direction of the guile rail is arranged in a direction of an X axis or in a vertically upright direction or in a Z direction perpendicular to the X axis and the vertically upright direction.

12. The rear stop device as claimed in claim 11, wherein the guide rail can be positioned via a positioning drive in the Z direction or in the vertically upright direction.

13. The rear stop device as claimed in claim 1, wherein a length of the support arm is between 5 and 90% of a length of the bearing arm.

14. The rear stop device as claimed in claim 1, wherein a length of the bearing arm between the rotary drive and the joint can be adjusted variably via a length adjusting drive.

15. A processing machine comprising a bending press, with a fixed pressing bar and a pressing bar adjustable relative to the latter and a rear stop unit, wherein the rear stop unit comprises at least one rear stop device as claimed in claimed 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For a better understanding of the invention the latter is explained in more detail with reference to the following Figures.

(2) In a schematically much simplified representation:

(3) FIG. 1 is a front view of a sheet metal processing machine for bending sheet metal including the rear stop device;

(4) FIG. 2 is a perspective view of a rear stop device;

(5) FIG. 3 is a perspective view of a rear stop device in an inverse position;

(6) FIG. 4 is an example of stopping options for positioning a flat metal sheet; detail of a stop finger;

(7) FIG. 5 is a detail of stop finger;

(8) FIG. 6 is an example of stopping options for positioning the prebent metal sheet; detail of stop finger;

(9) FIG. 7 is an example of additional stopping options for positioning a prebent metal sheet; detail of a stop finger.

DETAILED DESCRIPTION OF THE REFERRED EMBODIMENTS

(10) First of all, it should be noted that in the variously described exemplary embodiments the same parts have been given the same reference numerals and the same component names, whereby the disclosures contained throughout the entire description can be applied to the same parts with the same reference numerals and same component names. Also details relating to position used in the description, such as e.g. top, bottom, side etc. relate to the currently described and represented figure and in case of a change in position should be adjusted to the new position. Furthermore, also individual features or combinations of features from the various exemplary embodiments shown and described can represent in themselves independent or inventive solutions.

(11) All of the details relating to value ranges in the present description are defined such that the latter include any and all part ranges, e.g. a range of 1 to 10 means that all part ranges, starting from the lower limit of 1 to the upper limit 10 are included, i.e. the whole part range beginning with a lower limit of 1 or above and ending at an upper limit of 10 or less, e.g. 1 to 1.7, or 3.2 to 8.1 or 5.5 to 10.

(12) FIG. 1 shows a processing machine 1 comprising a bending press 2, in particular for bending a metal sheet 3, with a fixed pressing bar 4 and a pressing bar 5 adjustable relative to the latter. The processing machine 1 also comprises a rear stop device 6, which consists of at least one rear stop device 7. The rear stop device 7 is mounted in the shown example embodiment on the machine frame 8. However, it is not absolutely necessary for the rear stop device 7 to be mounted directly on the machine frame 8. An embodiment is also possible in which the rear stop device 7 is attached at the machine site as a separate unit directly to a shop floor and is not fitted onto the machine frame 8. In this case after the assembly the rear stop device 7 would have to be gauged precisely to the machine frame 8. To meet the requirements for precision of the metal sheet 3 to be bent it is practical however, if the rear stop device 7 is mounted directly on the machine frame 8.

(13) A control device 9 is also attached directly onto the machine frame 8 which is responsible for controlling the bending press 2 and the rear stop device 6. For controlling the rear stop device 6 it is possible that the latter has its own control unit which is connected to the control device 9 of the processing machine 1 by a bus system. A preferred variant however is one in which the actuators of the rear stop device 6 can be controlled in their movement directly by the control device 9 of the processing machine 1.

(14) As shown in FIGS. 2 and 3, the rear stop device 7 comprises a stop and/or gripping and/or measuring element 10. Said stop and/or gripping and/or measuring element 10 is responsible for the correct positioning of the metal sheet 3 and during the positioning process are in direct contact with the metal sheet 3. As a stop and/or gripping and/or measuring element 10 different elements can be used which are described in more detail below.

(15) An essential advantage of the invention is an embodiment in which the stop and/or gripping and/or measuring element 10 is connected by means of a pivot joint 12 to the bearing arm 13. It is ensured by means of this pivot joint 12 that an angle 14, between an X axis 16 perpendicular to the working plane 15 of the bending press 2 and the stop and/or gripping and/or measuring element 10 can be freely selected and adjusted. The free adjustment of the angle 14 is performed by a rotary drive 17, which is controlled by the control device 9 of the machine. The rotary drive 17 is preferably designed as a torque motor, wherein also other types of rotary drive 17 are possible, for example a belt drive with integrated position detection.

(16) To achieve an inexpensive alternative it can also be possible for the stop and/or gripping and/or measuring element 10 to be connected by means of a pulling mechanism drive 23, or by means of a rod assembly parallel to the bearing arm 13, which are also connected to the guiding element 19, and thus ensure that the angle in the stop and/or gripping and/or measuring element 10 always remain unchanged, regardless of the position of the bearing arm 13.

(17) The guiding element 19 and the guide rail 20 are connected to one another in a form-fitting manner to enable the sliding of the guiding element 19 in a guiding direction 11 of the guide rail 20.

(18) A support arm 21 is connected to the bearing arm 13 at one end by an additional joint 22, which is designed as a rotary slider joint. At the other end the support arm 21 is connected by a rigid connection to an additional guiding element 24.

(19) The arrangement of the bearing arm 13 and the support arm 21 relative to one another and the joint connection 22 in the form of a rotary slider joint ensures that by moving the support arm 21 relative to the bearing arm 13, the position of the bearing arm 13 can be changed.

(20) A quick-change device 25, which is not shown in detail but is suggested, is connected between the stop and/or gripping and/or measuring element 10 and the fixing point at the pivot joint 12. The use of a quick-change device 25 seems practical, if different tools or stop elements are used. The aim here is to enable the fastest and simplest changing of the individual tools. The quick-change device 25 can be controlled either by the control device 9 and thus enable an automatic tool change, or can be designed only for a manual tool change. The stop finger 26 which is described in more detail can either be designed as a separate stop element 10, or in combination with a gripping, or measuring element 10. It is also possible that the gripping element 10 does not have a separate stop finger 26 for example, but for the stop finger to form a part of the gripping or measuring element 10, and therefore have a double functionality.

(21) FIG. 3 shows the inverse position of the bearing arm 13, in which the latter is not inclined towards the working plane 15, but is inclined away from the latter. By means of this movability of the bearing arm 13 also in restricted spaces in the processing machine 1 the greatest possible flexibility is ensured with regard to the stopping options of metal sheets 3 of varying lengths. Here it is essential that the bearing arm 13 has a linear guide 27 in which the rotary push joint 22 can be displaced along a longitudinal direction A 28 on the bearing arm.

(22) The connection between the guide rail 20 and the guiding elements 19 and 24 can be designed so that the form-fitting connection between the guiding elements 19 and 24, and the guide rail 20 is performed by guiding surfaces 29, which are gripped behind by the two guiding elements 19 and 24 in the same manner. However, it is also possible that the guiding element 19 of the bearing arm 13 is connected in a form-fitting manner by the guiding surfaces 29 to the guide rail 20, and the guiding element 24 of the support arm 21 is connected by additional guiding surfaces 30 in a form-fitting manner to the guide rail. In this way it is advantageous, if the guide rail 20 has guiding surfaces 29 for the guiding element 19 and on the opposite side of the guide rail 20 has additional guiding surfaces 30 for the other guiding element 24. By means of a separate guiding of the guiding elements 19, 24 in the guide rail 20 it is possible that the guiding elements 19, 24 can be displaced independently of one another by two mechanical adjusting drives 32 and 33 in guiding direction 11. It can also be seen to be advantageous if the guiding elements 19 and 24 can be moved past one another in guiding direction 11 on the guide rail 20. The adjusting drives 32 and 33 can be designed for example as spindles, into which the guiding elements 19 and 24 engage which then had to have a ball joint drive. It is also possible that the adjusting drives 32 and 33 are formed for example by gear wheels which engage in the guide rail and thus enable an adjustment of the guiding elements 19, 24. It is also possible that the guiding elements 19, 24 are adjusted by a pulling means which is secured to the guiding elements 19, 24, or but also however that the guiding elements 19, 24 are positioned by a direct drive in the form of a linear magnetic drive. The drives for the different, shown embodiments can be arranged either directly on the guiding elements 19, 24, or can also be integrated into the machine frame 8. However, it is also possible that the guiding elements 19, 24 cannot be positioned individually and independently of one another in their position, but one of the guiding elements 19, 24 can be displaced by a mechanical main adjusting drive 34 in guiding direction 11, whereby it becomes a main guiding element, and that the respective other guiding element 19, 24 is coupled by an additional, mechanical adjusting drive 35, movably relative to the main guiding element 19, 24. In this way the main guiding element can be adjusted by one of the aforementioned adjusting drives and the additional guiding element 19, 24 can only be adjusted relative to the main guiding element 19, 24, which has the advantage that during adjusting processes of the stop finger 26, which only pass along an X direction 16, there is no need to adjust the other respective guiding element 19, 24. The adjustment of the other guiding element 19, 24 is performed by the mechanical coupling to the main guiding element 19, 24, whereby the guiding elements are thereby displaced jointly with one another.

(23) The guide rail 20 as a whole can be arranged so that the guiding direction 11 of the guide rail is arranged either in X direction 16 or in a vertical R direction 31. Said arrangements can ensure that the limited space between the bending press 2 can be used optimally. Furthermore, it is possible that the guide rail 20 can be positioned by means of a positioning drive 36 in a Z-direction 37 which is perpendicular to the X direction 16 and the R direction 31. The positioning drive 36 can be designed hereby in Z direction 37, as in the above examples of the positioning drives 32, 33 in different variants.

(24) The geometries of the support arm 21 and the bearing arm 13 can be configured in any way, however, to make optimal use of the space, it seems practical for the length x 38 of the support arm 21 to be between 5 and 90%, preferably between 40% and 60% of the length y 39 of the bearing arm 13. The bearing arm 13 and support arm 21 together form a supporting structure for the stop and/or gripping and/or measuring element 10, which is similar to the Greek letter lambda , whereby the bearing arm 13 corresponds to the longer straight section, which is supported by the shorter straight section in the form of the support arm 21. Further adjusting options are provided if the length y 39 of the bearing arm 13 can be adjusted variably between the rotary drive 17 and pivot joint 22 by means of a length adjusting drive 40. The length adjusting drive hereby changes the length y 39 of the bearing arm 13 in longitudinal direction A 29.

(25) FIG. 4, FIG. 6 and FIG. 7 show further examples of stopping options for the stop and/or gripping and/or measuring element 10. FIG. 4 shows a conventional stopping option in which the metal sheet 3 bears horizontally on a bending tool 41 mounted on the fixed pressing bar 4, and is stopped in horizontal direction against a stop finger 26. In this case it is an advantage, if the stop finger 26 has a step-like shoulder 42, whereby two mutually right-angled stop surfaces 43, 44 are formed, by means of which the metal sheet 3 can be positioned in X direction 16 and at the same time in R direction 31 the metal sheet 3 is supported against a possible bending due to gravity.

(26) FIG. 5 shows a detail of the stop finger, in which the two stop surfaces 43 and 44 are separated by a space 45, so that a possible bead or ridge in the metal sheet 3 caused by cutting does not cause a positioning error. It is an advantage if the stop finger 26 not only comprises said two stop surfaces 43 and 44, but if also additional surfaces are formed as stop surfaces 46, 47, the position of which can be determined or actively defined by the control device 9. By means of the additional stop surfaces 46, 47 additional stop options are provided, as shown in FIG. 6 and FIG. 7. For a stop as shown in FIG. 4, FIG. 6 or FIG. 7, it can be an advantage if a measuring unit 48 determines a rotary moment, which is introduced by a force at a distance A 49 from a rotary axis 50 of the pivot joint 12. The rotary moment can also be detected by a monitoring device of the motor current in the torque motor.

(27) The example embodiments show a possible embodiment variant of the processing machine 1 or the rear stop device 6, wherein it should be noted at this point that the invention is not limited to the embodiment variants thereof shown in particular.

(28) Finally, as a point of formality, it should be noted that for a better understanding of the structure of the processing machine 1 and the rear stop device 6 the latter and its components have not been represented true to scale in part and/or have been enlarged and/or reduced in size.

(29) The underlying objective of the independent solutions according to the invention can be taken from the description.

(30) Mainly the individual embodiments shown in FIGS. 1 to 7 can form the subject matter of independent solutions according to the invention. The objectives and solutions according to the invention relating thereto can be taken from the detailed descriptions of these figures.

(31) TABLE-US-00001 List of reference numerals 1 processing machine 2 bending press 3 metal sheet 4 fixed pressing bar 5 adjustable pressing bar 6 rear stop device 7 rear stop unit 8 machine frame 9 control device 10 stop and/or gripping and/or measuring element 11 guiding direction 12 pivot joint 13 bearing arm 14 angle 15 working plane 16 X axis 17 rotary drive 18 pivot joint 19 guiding element 20 guide rail 21 support arm 22 pivot joint 23 pulling mechanism drive 24 guiding element 25 quick-change device 26 stop finger 27 linear guide 28 longitudinal direction A 29 guiding surfaces 30 guiding surfaces 31 R axis 32 adjusting drive 33 adjusting drive 34 main adjusting drive 35 adjusting drive 36 positioning drive 37 Z axis 38 length x 39 length y 40 length adjusting drive 41 bending tool 42 step-like shoulder 43 stop surface 44 stop surface 45 free space 46 stop surface 47 stop surface 48 measuring unit 49 distance A 50 rotary axis 51 force