Integrating device to detect and recover the deformation of shoulders in a press-bending machine

Abstract

Integrating device to detect and recover the deformation of shoulders in a press-bending machine, including an optical ruler joined to the beater and reading trolley, pulled back elastically, and stressed by the false shoulder. The device provided for the false shoulder is made up of a rod perpendicular to the beater, which on one side is hinged to the shoulder of the machine, while on the opposite end, oscillating and facing the beater. It is stressed by the arm joined to the reading trolley of the optical ruler, and further in which the rod provides a slider in connection with an underlying plane plate that is part of the false shoulder.

Description

RELATED U.S. APPLICATIONS

[0001] not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not applicable.

REFERENCE TO MICROFICHE APPENDIX

[0003] Not applicable.

FIELD OF THE INVENTION

[0004] This invention refers to an integrating device to detect, recover and compensate the deformation of shoulders, in a press-bending machine.

[0005] The innovation finds particular even if not exclusive application in the field of machine tools.

BACKGROUND OF THE INVENTION

[0006] Press-bending machines, as known, are widely used in the engineering industry, and particularly in the working of metal sheets, to obtain, for example, differently shaped longitudinal sections, sometimes with the possibility of being each re-taken and subjected again to a cycle of press-bending.

[0007] Operatively, a press-bending cycle consists in the vertical descent of a tool, until it presses on the underlying metal sheet rested on the matrix, in carrying out the bending, and then, at the end, in proceeding with the ascent, up to a primary position. For carrying out the mentioned steps, the machine consists of two parts, respectively a first one, dynamic, generally engaging the upper part, and a substantially static part, constituting the underside of the machine placed perpendicular to the dynamic part. As far as the first dynamic part is concerned, in the execution of a press-bending cycle, a tool is provided for, made up of a differently shaped punch, also of the interchangeable type, which, supported by a beater or upper cross-piece, makes just one movement, along a vertical axis, of to and fro. The said movement is ensured by at least two oil-dynamic end-cylinders, which determine the descent, the possible stop and ascent of the beater that supports the tool longitudinally. Every cylinder group, in a traditional forming press, is joined and made integral with the frame or static body of the machine, and, in this case, to a corresponding side or side-shoulder of the frame of the press.

[0008] These characteristics give origin, during the pressing phase, to a multitude of rather strong forces, which develop in various known directions to engage the different parts of the machine, deforming them temporarily. Furthermore, some of these forces above all, end up modifying the shape of each shoulder even in a non-uniform way. It follows that during the execution phase of a press-bending cycle, a widespread deformation takes place, which affects in a negative way the qualitative result of the working required.

[0009] Tests carried out on the test stand, have evidenced that this characteristic temporary deformation of each shoulder, has its own logical progression the more the punch presses down on the sheet, and it is always proportional to the thickness of the sheet and to the type of material.

[0010] It therefore follows that it is necessary to have a control system that allows to detect the deflection of the shoulders, in order to intervene in the first stages of the working process. Then it is a question of correctly prearranging the forming press, in order that it can carry out a manufacturing cycle that will allow to achieve the predetermined bending angle with precision.

[0011] Actually, two techniques are known for solving the problem, which however do not seem completely satisfactory.

[0012] In one case, see for example TABLE 1, the movement of the beater G or punch carrying cap of the synchronized bending presses is given by two hydraulic cylinders, placed to the sides of the first and integral with the shoulders R, which assume the name of the two axes YI and Y2. These axes, Y1 and Y2, are checked sideways by optical rulers H where a small reading trolley I slides. The reading trolley I is hinged, through a L rod, to the upper end of a flexion recovery shoulder or false shoulder D, superimposed to the shoulder R, which is made integral, only on the underside, with the cross-piece F, with the platform M and with the matrix N (FIG. 1.1).

[0013] Considering the fact that the false shoulder D is integral with the cross-piece F, with the platform M and with the matrix N, the punch O should, both when under pressure and when load-less, maintain a locating spot in correspondence with the bottom dead center 0 (see FIG. 1.2). Intuitively, this should take place because the false shoulder D is not engaged to the shoulder R.

[0014] A second system, not shown, but just as common, is the solution originally suggested by the Beyler Company. It refers to an electronic card consisting of a data base, cooperating with the logical unit of the machine, where a great number of data relative to the known deformations is stored, therefore including the deformation of shoulders, in relation to an entire series of parameters, namely: extension of the carpentry, extension of optical lines, changes on the viscosity of the oil, electric de-compensations, de-compensations in the control of the valves. This data have been previously acquired on the basis of a series of tests and subsequently transferred to the database. The processing and the comparing of these by a logical unit with others values, allows to define, in a manufacturing cycle of the sheet, ascribable theoretic values foreseeable in the localized deformation of the shoulders that therefore will be conveniently recovered.

[0015] As regards the first of the mentioned solutions, the use of the traditional optical ruler does not seem to be at all sufficient to allow a precise recovery of the deflection of the false shoulder and consequently obtain the predetermined angle. In fact (see FIG. 1.3) even reaching the planned value of the trolley on the optical ruler H, under pressure the point 0 is not held as happens instead in the load-less condition (see FIG. 1.2). This difference is due in part to the crushing of some parts of the machine, as for example in the underside the cross-piece F, the platform M and the matrix N, which, altering the value in reference to height B, cause a variation in the value of the dimension A. In the same way, in the upper part of the machine the same crush is created between punch 0 and beater G causing a variation of dimension Δ. Furthermore, with the deformation of shoulder R, a displacement C of the upper part of the false shoulder D takes place and therefore of the hinging point of the lower extremity of lever L of the trolley I, which in this hypothesis advances. During the working process, the displacement of the false shoulder D opposite to that of shoulder R concurs in emphasizing the phenomenon, as indicated by letters P and Q. Finally, one detects that value C is proportional to arm E that is placed between the anchorage point of the lever L to the trolley I.

[0016] The consequence, therefore, is that the reaching of spot 0 by the machine Δ in a load-less condition, is different from when the system is under pressure, Δ1, for the total diversity of points A, B and C.

[0017] As regards the solution suggested by Beyler, one observes, as in the previous proposal, the basic impossibility of achieving a correct recovery of the deflection of the shoulders, that would allow to carry-out with precision the predetermined bending angle. This is substantially due to the fact that the values of points A, B and C, are presumed and do not correspond to the ones actually measured, or real, obtainable from the single measuring of phenomena during the execution of the press-bending cycle of a sheet.

[0018] Therefore there is the need for companies to find alternative and more effective systems than the ones described above.

[0019] A purpose of the present proposal is also to avoid the abovementioned drawbacks.

BRIEF SUMMARY OF THE INVENTION

[0020] This and other purposes are achieved with this innovation according to the characteristics as in the included claims, solving the mentioned problems, with an integrating device to detect and recover the deformation of shoulders, in a press-bending machine, including an optical rulerjoined to the beater and a reading trolley, pulled back elastically, stressed by the false shoulder; said device provided for above the false shoulder, being made up of a rod placed perpendicular to the beater, which is hinged to the shoulder of the machine on one side, while the opposite end, oscillating and directed towards said beater, is stressed by the arm joined to the reading trolley of the optical ruler, and furthermore in which said rod provides a sliding device in correspondence with an underlying plane plate that is part of the false shoulder.

[0021] The considerable creative contribution, found in the proposal now described, determines an immediate technical progress, allowing to obtain various advantages.

[0022] First of all, the system gives the user the possibility of finding the desired angle in a fast way, with intuitable and extremely simple operations. More particularly, first it carries out tests on a small piece to then take it on to a definite piece, even along the total length of the machine or differently placed along the fold-line (right, left and center). All this independently of the bending force, that, as known, varies according to what piece has to be bent.

[0023] Secondly, this system has the advantage of correcting automatically the different flexions noticeable from one shoulder to the other, caused by variations in the thickness of the material with which the shoulders are obtained, by the diversity of the materials, as well as by continuous variations in the temperature of the environment where the said machine is made operative.

[0024] Amongst the peculiarities of this invention, we also point out the fact that, under the executive point of view, having two metal-sheets of the same length but with a different bending section, the result between the two pieces is maintained constant.

[0025] An additional advantageous point refers to the lack of particular complications in the device; this implies almost an absence of maintenance with rather low costs, relatively to the construction and to installation. The particularity of the device, additionally, also allows installations on already existing machines, favoring an increase in quality and, as a whole, in the works in progress.

[0026] These advantages have the all but negligible value of obtaining a product with a good technological content, functional and extremely reliable, even if submitted to particular working conditions.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0027] Other advantages will appear from the following specific description of some preferred embodiments, with the aid of the included schematic drawings, whose details of execution are not to be considered limitative, but only illustrative.

[0028] FIG. 1, represents a side view of a portion of the press-bending machine, to which a device for the control of the deflection of the shoulder is joined, taken in correspondence with the working area.

[0029] FIG. 2, is always a side view of a portion of a press-bending machine as in the previous figure, comprehensive of the device for the control of the deflection of the shoulder, represented in a load-less working condition.

[0030] FIG. 3, is again a side view of a portion of a press-bending machine as in FIG. 1, but represented in an effective working condition.

[0031] FIG. 4, illustrates sideways a portion of a press-bending machine, with a different version of the device for the control of the deflection of the shoulder.

[0032] FIG. 5, is a side view of a portion of a press-bending machine as in the previous figure, represented in a load-less working condition.

[0033] FIG. 6, is again a side view of a portion of a press-bending machine as in FIG. 4, but represented in an effective working condition.

[0034] FIG. 7 is an enlarged side view of the detail as in FIG. 1, of a portion of the press-bending machine, to which a device for the control of the deflection of the shoulder is joined, taken in correspondence with the working area.

[0035] FIG. 8 is an enlarged side view of the portion of press-bending machine of FIG. 4, which represents the different version of the device for the control of the deflection of the shoulder.

[0036] FIG. 9 is an additional enlargement of a detail of the portion of press-bending machine of FIG. 4.

[0037] Finally, FIG. 10, is an overall and frontal view of a press-bending machine.

DETAILED DESCRIPTION OF THE INVENTION

[0038] Also with reference to the figures, one can detect that a press-bending machine (A), provided with a device for the control of the deflection of the shoulder, includes an upper beater (1), vertically mobile with respect to the frame, to the lower end of which an interchangeable type tool is associated longitudinally, realizing the punch (2). Always the machine (A), provides at the two ends a cylinder group for each side (3, 4), which being synchronous, determine the downward and upward vertical movement of the beater (1) towards the underlying cross-piece (5), which supports a platform (6) which supports the matrix (7), also of the interchangeable type.

[0039] With the purpose of detecting and later on allowing the recovery of the deflections that both the shoulders (8) undergo, during the execution of a press-bending cycle, for example of a metal sheet (Z) interposed between the matrix (7) and the punch (2), false shoulders or flexion recovery shoulders (9a, 9b) are provided for each of said shoulders (8), set on the side facing towards the exterior.

[0040] Every false shoulder (9a, 9b), composed of a robust metallic body plate on both the sides, presents a characteristic “C” shape where the empty part faces towards the tool (2) and the underlying matrix (7). As regards the fixing of the false shoulder (9a, 9b), it is provided for only in correspondence with the lower end (91a, 91b), in such a way as to make it integral with the lower cross-piece (5), as it is directly joined to the latter, and integral with the bed (6) and the matrix (7).

[0041] There is also an optical ruler (10) joined to the beater (1), cooperating with a reading trolley (100). This reading trolley (100), instead of being directly fixed to the false shoulder (9a, 9b), as seen in previous solutions, is now equipped with a small cantilevered arm (101), with a bearing (102) at the end which insists in correspondence with the extremity (111, 141) of a rod (11, 14) for the neutralization of horizontal end plays hinged in (112, 143) to the shoulder (8). The necessary and constant contact of the bearing (102) along the rod (11, 14), that in this case is of the type made of harmonic steel, is ensured by the action of an underlying elastic means (12), which on one side is engaged to the shoulder (8) and on the other to the reading trolley (100).

[0042] In a first proposition of the invention, with the purpose of controlling the oscillation of the rod that neutralizes the end play (11), along the latter a movable body (13) is provided for. This movable body (13), which is nothing less than a trolley, in the underside is provided with a point of support (131), for example a bearing, which slides along the flat edge of the upper end (921) of the false shoulder (9a). In this way, the rod (11) takes on the function of a second-degree lever, so that when the position of the movable body (13) varies, the width of the movement of the rod varies proportionally to the deformation of the shoulder due to the pressure exerted by the cylinders for the bending.

[0043] Operatively, to make sure that the point 0 does not change when the pressure varies, one will have to act on the movable body (13). This action determines the variation of the value (K) until point 0 is not maintained constant even when variations of the pressure take place.

[0044] The described condition, in such a case, is reached thanks to the movement in opposite directions (P, Q) of the shoulder (8) and of the false shoulder (9a), which contextually determines the movement of the movable body (13) along the plane (921). Thanks to the sliding of the movable body (13) with respect to the plane (921) of the extremity (92a) of the false shoulder (9a), it is possible to maintain the value of the optical ruler (10) and to get the beater (1) down until it reaches the position 0 (value reached in a load-less condition) proportionally to the pressure exerted on the beater (1).

[0045] A different version of the mentioned device is represented in the following FIGS. 4, 5 and 6. Also in this hypothesis, with the purpose of detecting and recovering the flexions that both the shoulders (8) undergo, during the execution of a press-bending cycle, for example of a metal sheet (Z) interposed between the matrix (7) and the punch (2), false shoulders or flexion recovery shoulders (9b) are provided, for each of the shoulders (8), set on the side facing towards the exterior.

[0046] Each of the two false shoulders (9b), is composed by a robust metallic body, flat on both sides, with a characteristic “C” shape where the hollow part faces towards the tool (2) and the underlying matrix (7). Also in such case, the fixing of the false soulder (9b) is provided for only in correspondence with the lower end (91b), in such a way to make it integral with the cross-piece (5), as it is directly-joined to it, and integral with the bed (6) and the matrix (7).

[0047] An optical ruler (10) is always present, joined to the beater (1), cooperating with a reading trolley (100). The said reading trolley (100), is equipped with a small arm (101), with at the end a bearing (102) which insists in correspondence of the extremity (141) of a steel rod (14) for neutralizing horizontal end games. The necessary and constant contact of the bearing (102) along the top-side of the rod (14) is ensured by the action of an elastic means (12) which, on one side, is engaged to the shoulder (8), on the other to the reading trolley (100).

[0048] Furthermore, one detects that above the extremity (92b) of the false shoulder (9b), the said end game neutralizing rod (14) is hinged in correspondence with point (143) to the shoulder (8). This rod is provided, along the bottom side in correspondence with the extremity (141), with a bearing (142), which engages along an adjustable plane (15), provided with reference graduations with relation to the measuring of degrees allowing to establish a more or less stronger inclination. In more detail, said adjustable plane (15) is hinged in correspondence with the higher extremity (92b) of the false shoulder (9b), which has a short extension section directed vertically, for the support of said adjustable plane (15).

[0049] Operatively, during pressing, the false shoulder (9b) moves in direction (P) and the shoulder (8) in the opposite direction (Q), so that, as the rod (14) is anchored to the shoulder (8), the bearing (142) runs along the adjustable plane (15) creating therefore a movement along a vertical direction (K) proportional to the power at work.

[0050] The plane (15), is inclined until the maintenance of point 0 of the punch (2) is achieved, in a practical way, at any working pressure. This is thanks to the movement in opposite directions of (P) and (Q) which makes the bearing (142) run along the inclined plane (15). Thanks to the sliding of the bearing (142) with respect to the plane (15) it is possible to maintain the value of the optical ruler and get the beater (1) down until it reaches the position 0 [value reached when load-less] proportionally to the pressure exerted on the beater (1).

[0051] After accurately setting-up the angle, the system recovers the anomalies of deformations and flexions of the shoulders (8) due to movements (P, Q) and of compressions therefore maintaining point 0 (value reaching point) constant whatever the pressure, both in a load-less condition and under maximum load.

Claims

1. Device to detect the deformation of shoulders in a press-bending machine, including an optical ruler (10) joined to the beater (1) and a reading trolley (100) stressed by the false shoulder, characterized in that it is made up of a rod (11, 14) placed perpendicular to the beater (1), which is hinged (112, 143) on one side to the shoulder (8) of the machine, while the opposite end (111, 141), oscillating and directed towards the said beater (1), is stressed by the arm (101, 102) joined to the reading trolley (100) of the optical ruler (10), and furthermore in which said rod (11, 14) provides a sliding means (142, 13, 131) in correspondence with an underlying plane plate (15, 921) that is part of the false shoulder (9a, 9b).

2. Device to detect the deformation of shoulders according to claim 1, characterized in that it is placed on top of the false shoulder (9a, 9b).

3. Device to detect the deformation of shoulders according to claims 1 and 2, characterized in that the reading trolley (100) of the optical ruler (10), is equipped with at least one overhanging arm (101) with a bearing (102) at the end, and includes an elastic recovering means (12) which on one side is engaged to the shoulder (8) and on the other to the reading trolley (100).

4. Device to detect the deformation of shoulders according to previous claims, characterized in that along the end play neutralizing rod (11) a movable body, like a trolley (13), is provided for, which in the underside has a point of support (131) that slides along the flat edge (921) of the higher extremity (92a) of the false shoulder (9a).

5. Device to detect the deformation of shoulders according to previous claims, characterized in that due to the sliding of the movable body (13) with respect to the plane (921) of the extremity (92a) of the false shoulder (9a), it is possible to maintain the value of the optical ruler (10) and get the beater (1) down until it reaches position 0, value reached when load-less, proportionally to the pressure exerted on the beater (1).

6. Device to detect the deformation of shoulders according to claims from 1 to 3, characterized in that above the extremity (92b) of the false shoulder (9b), the end game neutralizing rod (14) is hinged in (143) to the shoulder (8), at the end (141) of which, along the bottom side, a bearing (142) is provided for, which insists along an adjustable plane (15), hinged to the false shoulder (9b).

7. Device to detect the deformation of shoulders according to claims from 1 to 3 and 6, characterized in that said adjustable plane (15) is hinged in correspondence with the higher extremity (92b) of the false shoulder (9b), which is equipped with a short extension section directed vertically, for the support of said adjustable plane (15).

8. Device to detect the deformation of shoulders according to claims from 1 to 3, and 6 and 7, characterized in that the plane (15), is inclined until it achieves, in a practical way, the maintenance of point 0 of the punch (2) at any level of working pressure.

9. Device to detect the deformation of shoulders according to previous claims, characterized in that the rod (11, 14), is of the type made of harmonic steel.